Концентрация белка ликвора оставалась стабильной после хранения: исследование собак и кошек

Что учитывать: Выборка небольшая, особенно у кошек, и включает животных с разными заболеваниями; результат не даёт гарантии для любого будущего образца. Срок замораживания различался между образцами, а часть повторных измерений отсутствовала. Это ограничивает сопоставимость этапов. Максимальные наблюдавшиеся сроки не являются установленным сроком годности каждого образца. Вывод касается общего белка, измеренного использованным методом. Он не подтверждает сохранность всех показателей анализа ликвора; отдельные белковые биомаркеры требуют самостоятельного изучения. В абзаце результатов с величинами колебаний есть несогласованность средних значений, диапазонов и единиц. По этому описанию нельзя надёжно установить точную величину колебаний концентрации.

Не обязательно. В этой небольшой выборке охлаждение и последующее замораживание не изменили интерпретацию измерений общего белка ликвора — спинномозговой жидкости. Результат относится к исследованным образцам собак и кошек и использованному лабораторному методу.

На чём основано · 1

В исследованных образцах авторы не обнаружили статистически значимого изменения концентрации белка ликвора со временем хранения: p = 0,334 у собак и p = 0,785 у кошек. Различия между свежими и хранившимися образцами не изменили интерпретацию ни одного результата в этой выборке.

Граница вывода: Отсутствие статистически значимого изменения в небольшой выборке не доказывает полного совпадения измерений или гарантированной стабильности любого образца. В абзаце Results есть несогласованные диапазоны и единицы для величин колебаний; они сохранены дословно в evidence 987 и не используются как надёжная количественная оценка погрешности.

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 2.2 Protein Measurement, абзацы 1–2: аналитический метод, последовательность измерений и условия хранения.

Источник: Luana S. Ribeiro, Aude Castel, Bruno B. J. Torres. Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time. Veterinary Clinical Pathology, 2026. DOI: 10.1111/vcp.70131

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, абзац после подписи TABLE 2, начинается «CSF protein concentration at each time»: результаты анализа, вариации и клиническая интерпретация. Числовые расхождения сохранены дословно.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 2

Вывод исследования относится к концентрации белка ликвора, измеренной использованным лабораторным методом. Стабильность отдельных белковых биомаркеров требует самостоятельного изучения.

Граница вывода: По этой работе нельзя делать вывод, что после хранения весь анализ ликвора остаётся неизменным или что любой специализированный белковый тест даст тот же результат.

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 4 Discussion, абзац начинается «It is recommended that CSF analysis»: максимальные сроки отдельно для собак и кошек, применимость к белку и необходимость изучения отдельных биомаркеров.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

It is recommended that CSF analysis be conducted within 30 to 60 min of collection. However, some veterinary centers must send samples to specialized diagnostic laboratories, resulting in potential delays of 4 to 8 h and even longer during non‐business hours [3]. Additionally, a recent study in dogs has demonstrated that CSF proteins should not be evaluated using urinary dipsticks, highlighting the limitations of in‐house testing methods [10]. In veterinary practice, CSF samples are refrigerated until they can be analyzed for protein [3]. Typically, this delay can extend to 48 h (e.g., over weekends), which is the time frame often encountered in routine clinical settings. During this period, in our study, CSF samples showed stability in both dogs and cats. Consequently, CSF samples may encounter delays in frozen storage [4]. Notably, CSF protein measurements did not exhibit significant variation in frozen samples at −20°C after a 48°h delay compared to fresh or refrigerated, remaining stable for up to 150 days in dogs and 133 days in cats, which demonstrates the viability of batching these samples for research or laboratory control. It is important to emphasize that studies on the stability of specific protein biomarkers should be conducted, like those performed in human medicine [5].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Что это значит при отправке образца в лабораторию

Пример применения: клиника сообщает, что образец ликвора сначала хранили 48 часов при 4 °C, затем заморозили при −20 °C. Такая последовательность изучалась в работе; сам факт такого хранения не означает, что результат измерения общего белка непригоден. При этом сохранность клеточного состава и отдельных белковых биомаркеров из этого результата не следует.

На чём основано · 1

Белок ликвора измеряли пирогаллоловым красным методом сразу после получения образца, после 48 часов при 4 °C и после последующего замораживания при −20 °C; сроки хранения до последнего анализа составляли от 6 до 150 дней. Не все образцы прошли все этапы измерения.

Граница вывода: Пропущенные измерения означают, что сравнения на разных этапах основаны на неодинаковом числе образцов. Этот протокол нельзя приравнивать к хранению при комнатной температуре или к многократному размораживанию.

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 2

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 3

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

It is recommended that CSF analysis be conducted within 30 to 60 min of collection. However, some veterinary centers must send samples to specialized diagnostic laboratories, resulting in potential delays of 4 to 8 h and even longer during non‐business hours [3]. Additionally, a recent study in dogs has demonstrated that CSF proteins should not be evaluated using urinary dipsticks, highlighting the limitations of in‐house testing methods [10]. In veterinary practice, CSF samples are refrigerated until they can be analyzed for protein [3]. Typically, this delay can extend to 48 h (e.g., over weekends), which is the time frame often encountered in routine clinical settings. During this period, in our study, CSF samples showed stability in both dogs and cats. Consequently, CSF samples may encounter delays in frozen storage [4]. Notably, CSF protein measurements did not exhibit significant variation in frozen samples at −20°C after a 48°h delay compared to fresh or refrigerated, remaining stable for up to 150 days in dogs and 133 days in cats, which demonstrates the viability of batching these samples for research or laboratory control. It is important to emphasize that studies on the stability of specific protein biomarkers should be conducted, like those performed in human medicine [5].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Как проводили исследование

Образцы собирали в университетской ветеринарной клинике Монреаля. В исследование включили 23 животных: 14 собак и 9 кошек. У всех собак и 4 кошек были неврологические признаки; остальные кошки были подвергнуты эвтаназии из-за терминальных состояний, не связанных с неврологическими заболеваниями. Сбор описан как проспективный; в итоговую выборку вошли также образцы 3 собак из предыдущей работы этой исследовательской группы.

На чём основано

В исследование стабильности белка ликвора включили 23 животных: 14 собак и 9 кошек. Неврологические признаки были у всех собак и у 4 кошек; остальные кошки были подвергнуты эвтаназии из-за терминальных состояний, не связанных с неврологическими заболеваниями. Образцы 3 собак были получены в предыдущем исследовании этой группы.

Граница вывода: Небольшая клиническая выборка, особенно кошек, не представляет популяцию здоровых домашних животных. Происхождение части образцов из предыдущей работы необходимо учитывать при описании дизайна и пропущенных измерений.

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; раздел 2.1 Cerebrospinal Fluid Samples and Collection, первый абзац, первое предложение. Уточнение локатора 984: ссылка на раздел и предложение текстового представления source.text; хеш хранилища не используется как идентификатор этого представления.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF samples were prospectively collected from dogs and cats presented to the University Veterinary Hospital of the Faculty of Veterinary Medicine of Montreal University for diagnostic purposes.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Общий белок определяли пирогаллоловым красным методом на анализаторе UniCel D × C 600. Сравнивали повторные измерения одних и тех же образцов.

На чём основано

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Последовательность измерений в исследовании
Этап	Условия
Первое измерение	Сразу после получения образца
После охлаждения	48 часов при 4 °C
После последующего замораживания	−20 °C; сроки от 6 до 150 дней

На чём основано

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Не все образцы прошли все этапы: у 3 собак не было измерения после охлаждения, поскольку их образцы были получены в предыдущей работе группы. У 3 кошек не было измерения после замораживания из-за недостаточного объёма образца.

На чём основано · 1

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF samples were prospectively collected from dogs and cats presented to the University Veterinary Hospital of the Faculty of Veterinary Medicine of Montreal University for diagnostic purposes.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 2

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Что получили

Авторы не обнаружили статистически значимого изменения концентрации белка со временем хранения: p = 0,334 у собак и p = 0,785 у кошек. Колебания между свежими и хранившимися образцами не изменили интерпретацию ни одного изученного результата. После предварительного охлаждения авторы описали стабильность белка при −20 °C в пределах наблюдавшихся сроков: до 150 дней у собак и до 133 дней у кошек.

На чём основано · 1

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 2

После предварительного охлаждения образцов в течение 48 часов при 4 °C авторы описали стабильность измеряемого белка при −20 °C в пределах наблюдавшихся сроков: до 150 дней у собак и до 133 дней у кошек.

Граница вывода: Максимальный наблюдавшийся срок не является установленным сроком годности для каждого образца. Все образцы не хранили одинаково долго; результат у собак до 150 дней нельзя автоматически переносить на кошек.

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

It is recommended that CSF analysis be conducted within 30 to 60 min of collection. However, some veterinary centers must send samples to specialized diagnostic laboratories, resulting in potential delays of 4 to 8 h and even longer during non‐business hours [3]. Additionally, a recent study in dogs has demonstrated that CSF proteins should not be evaluated using urinary dipsticks, highlighting the limitations of in‐house testing methods [10]. In veterinary practice, CSF samples are refrigerated until they can be analyzed for protein [3]. Typically, this delay can extend to 48 h (e.g., over weekends), which is the time frame often encountered in routine clinical settings. During this period, in our study, CSF samples showed stability in both dogs and cats. Consequently, CSF samples may encounter delays in frozen storage [4]. Notably, CSF protein measurements did not exhibit significant variation in frozen samples at −20°C after a 48°h delay compared to fresh or refrigerated, remaining stable for up to 150 days in dogs and 133 days in cats, which demonstrates the viability of batching these samples for research or laboratory control. It is important to emphasize that studies on the stability of specific protein biomarkers should be conducted, like those performed in human medicine [5].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Где заканчивается применимость результата

Выборка небольшая, особенно у кошек, и включает животных с разными заболеваниями; результат не даёт гарантии для любого будущего образца.
Срок замораживания различался между образцами, а часть повторных измерений отсутствовала. Это ограничивает сопоставимость этапов. Максимальные наблюдавшиеся сроки не являются установленным сроком годности каждого образца.
Вывод касается общего белка, измеренного использованным методом. Он не подтверждает сохранность всех показателей анализа ликвора; отдельные белковые биомаркеры требуют самостоятельного изучения.
В абзаце результатов с величинами колебаний есть несогласованность средних значений, диапазонов и единиц. По этому описанию нельзя надёжно установить точную величину колебаний концентрации.

На чём основано · 1

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF samples were prospectively collected from dogs and cats presented to the University Veterinary Hospital of the Faculty of Veterinary Medicine of Montreal University for diagnostic purposes.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 2

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 3

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 4

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

It is recommended that CSF analysis be conducted within 30 to 60 min of collection. However, some veterinary centers must send samples to specialized diagnostic laboratories, resulting in potential delays of 4 to 8 h and even longer during non‐business hours [3]. Additionally, a recent study in dogs has demonstrated that CSF proteins should not be evaluated using urinary dipsticks, highlighting the limitations of in‐house testing methods [10]. In veterinary practice, CSF samples are refrigerated until they can be analyzed for protein [3]. Typically, this delay can extend to 48 h (e.g., over weekends), which is the time frame often encountered in routine clinical settings. During this period, in our study, CSF samples showed stability in both dogs and cats. Consequently, CSF samples may encounter delays in frozen storage [4]. Notably, CSF protein measurements did not exhibit significant variation in frozen samples at −20°C after a 48°h delay compared to fresh or refrigerated, remaining stable for up to 150 days in dogs and 133 days in cats, which demonstrates the viability of batching these samples for research or laboratory control. It is important to emphasize that studies on the stability of specific protein biomarkers should be conducted, like those performed in human medicine [5].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 5

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

It is recommended that CSF analysis be conducted within 30 to 60 min of collection. However, some veterinary centers must send samples to specialized diagnostic laboratories, resulting in potential delays of 4 to 8 h and even longer during non‐business hours [3]. Additionally, a recent study in dogs has demonstrated that CSF proteins should not be evaluated using urinary dipsticks, highlighting the limitations of in‐house testing methods [10]. In veterinary practice, CSF samples are refrigerated until they can be analyzed for protein [3]. Typically, this delay can extend to 48 h (e.g., over weekends), which is the time frame often encountered in routine clinical settings. During this period, in our study, CSF samples showed stability in both dogs and cats. Consequently, CSF samples may encounter delays in frozen storage [4]. Notably, CSF protein measurements did not exhibit significant variation in frozen samples at −20°C after a 48°h delay compared to fresh or refrigerated, remaining stable for up to 150 days in dogs and 133 days in cats, which demonstrates the viability of batching these samples for research or laboratory control. It is important to emphasize that studies on the stability of specific protein biomarkers should be conducted, like those performed in human medicine [5].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Что обсудить с клиникой

Уточните, какой показатель обсуждается: общий белок ликвора или другой результат анализа.
Если беспокойство связано с хранением, спросите клинику о температуре и последовательности обработки образца: вывод исследования относится к описанным условиям.
Обсудите с ветеринарным врачом интерпретацию результата общего белка отдельно от остальных показателей ликвора.

На чём основано · 1

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 2

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 3

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

It is recommended that CSF analysis be conducted within 30 to 60 min of collection. However, some veterinary centers must send samples to specialized diagnostic laboratories, resulting in potential delays of 4 to 8 h and even longer during non‐business hours [3]. Additionally, a recent study in dogs has demonstrated that CSF proteins should not be evaluated using urinary dipsticks, highlighting the limitations of in‐house testing methods [10]. In veterinary practice, CSF samples are refrigerated until they can be analyzed for protein [3]. Typically, this delay can extend to 48 h (e.g., over weekends), which is the time frame often encountered in routine clinical settings. During this period, in our study, CSF samples showed stability in both dogs and cats. Consequently, CSF samples may encounter delays in frozen storage [4]. Notably, CSF protein measurements did not exhibit significant variation in frozen samples at −20°C after a 48°h delay compared to fresh or refrigerated, remaining stable for up to 150 days in dogs and 133 days in cats, which demonstrates the viability of batching these samples for research or laboratory control. It is important to emphasize that studies on the stability of specific protein biomarkers should be conducted, like those performed in human medicine [5].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Финансирование и конфликты интересов

Авторы сообщили о поддержке Coordenação de Aperfeiçoamento de Pessoal de Nível Superior и PremieRpet Institute и заявили об отсутствии конфликтов интересов.

На чём основано

Авторы сообщили о поддержке исследования со стороны Coordenação de Aperfeiçoamento de Pessoal de Nível Superior и PremieRpet Institute и заявили об отсутствии конфликтов интересов.

Граница вывода: Это содержание авторских деклараций, а не независимое подтверждение отсутствия возможного влияния финансирования.

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; разделы Funding и Conflicts of Interest: заявленные финансирование и конфликты интересов.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Funding This work was supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior and PremieRpet Institute. Conflicts of Interest The authors declare no conflicts of interest.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 1

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF samples were prospectively collected from dogs and cats presented to the University Veterinary Hospital of the Faculty of Veterinary Medicine of Montreal University for diagnostic purposes.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 2

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 3

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 4

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

It is recommended that CSF analysis be conducted within 30 to 60 min of collection. However, some veterinary centers must send samples to specialized diagnostic laboratories, resulting in potential delays of 4 to 8 h and even longer during non‐business hours [3]. Additionally, a recent study in dogs has demonstrated that CSF proteins should not be evaluated using urinary dipsticks, highlighting the limitations of in‐house testing methods [10]. In veterinary practice, CSF samples are refrigerated until they can be analyzed for protein [3]. Typically, this delay can extend to 48 h (e.g., over weekends), which is the time frame often encountered in routine clinical settings. During this period, in our study, CSF samples showed stability in both dogs and cats. Consequently, CSF samples may encounter delays in frozen storage [4]. Notably, CSF protein measurements did not exhibit significant variation in frozen samples at −20°C after a 48°h delay compared to fresh or refrigerated, remaining stable for up to 150 days in dogs and 133 days in cats, which demonstrates the viability of batching these samples for research or laboratory control. It is important to emphasize that studies on the stability of specific protein biomarkers should be conducted, like those performed in human medicine [5].

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Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein levels were measured using the pyrogallol red method on an automatic Chemistry Analyzer UniCel D × C 600 (Beckman Coulter, Brea, California, USA). The detection range was from 0.06 to 3 g/L. Samples exceeding this range were diluted with saline. Samples with high cellularity were centrifuged at 3710 × g for 10 min, and the supernatant was used for measurement. The analyses were conducted immediately after collection. Subsequently, samples were refrigerated at 4°C for 48 h. A second measurement was performed after this period, and the samples were then frozen at −20°C until all analyses were completed on the same day, within a timeframe of 6 to 150 days. CSF protein level was considered increased when the values were higher than 0.30 g/dL for cerebellomedullary punctions and higher than 0.45 g/dL for CSF collected at the lumbar space [6].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; 3 Results, первый абзац перед TABLE 1: состав выборки и пропущенные измерения.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Twenty‐three animals met the inclusion criteria and were enrolled in the study, including 14 dogs and nine cats. All the dogs and four cats had neurological signs, while the remaining cats were euthanized due to various terminal conditions unrelated to neurological issues. Three CSF samples from dogs were not measured for protein 48 h after refrigeration because they were obtained from a previous study conducted by our research team. In addition, three CSF samples from cats were not evaluated after being frozen due to insufficient sample volume (Tables 1 and 2).

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

CSF protein concentration at each time and mean duration of freezing are presented in Table 3. Protein measurements remained stable over time for both dogs (p = 0.334) and cats (p = 0.785), regardless of the timing of analysis (Figure 1). The average variation in results between fresh and refrigerated samples was 2 mg/dL (range: 0 to 1 mg/dL) for dogs and 2 mg/dL (range: 0 to 8 mg/dL) for cats. In frozen samples, the average variation was 6 mg/dL (range: 0 to 21 g/dL) for dogs and 3 mg/dL (range: 1 to 9 mg/dL) for cats. Variations observed in protein concentrations sometimes increased and sometimes decreased over time, with fluctuations observed in both refrigerated and frozen conditions. However, the variation found between the CSF protein measurements in fresh and stored samples did not change the interpretation of any results.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

It is recommended that CSF analysis be conducted within 30 to 60 min of collection. However, some veterinary centers must send samples to specialized diagnostic laboratories, resulting in potential delays of 4 to 8 h and even longer during non‐business hours [3]. Additionally, a recent study in dogs has demonstrated that CSF proteins should not be evaluated using urinary dipsticks, highlighting the limitations of in‐house testing methods [10]. In veterinary practice, CSF samples are refrigerated until they can be analyzed for protein [3]. Typically, this delay can extend to 48 h (e.g., over weekends), which is the time frame often encountered in routine clinical settings. During this period, in our study, CSF samples showed stability in both dogs and cats. Consequently, CSF samples may encounter delays in frozen storage [4]. Notably, CSF protein measurements did not exhibit significant variation in frozen samples at −20°C after a 48°h delay compared to fresh or refrigerated, remaining stable for up to 150 days in dogs and 133 days in cats, which demonstrates the viability of batching these samples for research or laboratory control. It is important to emphasize that studies on the stability of specific protein biomarkers should be conducted, like those performed in human medicine [5].

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

На чём основано · 6

Stability of Cerebrospinal Fluid Proteins in Dogs and Cats: Effects of Refrigeration and Freezing Over Time.

Точное место: DOI 10.1111/vcp.70131; разделы Funding и Conflicts of Interest: заявленные финансирование и конфликты интересов.

Условия использования: Creative Commons Attribution (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/ Лицензия источника

Funding This work was supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior and PremieRpet Institute. Conflicts of Interest The authors declare no conflicts of interest.

Связь с утверждением: подтверждает · полный текст · DOI 10.1111/vcp.70131 · опубликован 1 июня 2026

Об этом материале

Кому и где применимо: Для владельцев собак и кошек, которым нужно понять результат исследования хранения образцов ликвора. Применимость ограничена общим белком, пирогаллоловым красным методом и описанной последовательностью охлаждения и замораживания в лаборатории.

Проверка и история

Опубликовано: 28 октября 2026
Проверено: 28 октября 2026
Финансирование: По заявлению авторов: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior и PremieRpet Institute.
Конфликт интересов: Авторы заявили об отсутствии конфликтов интересов.

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28 октября 2026 · Опубликована версия

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