Effects of storage duration on compressive mechanical properties of rabbit patellar ligament / 医用生物力学

Objective To study the effect of storage duration on compressive mechanical properties of rabbit patellar, so as to provide references for in vitro ligament storage.Methods The compressive mechanical properties of rabbit patellar ligament storaged at -20 ℃ at different storage durations (in 36 d) were tested with the universal tensile test machine. The microscopic morphology of collagen fibers was observed under the scanning electron microscopy (SEM). The enthalpy and denaturation temperature of collagen fibers were measured with differential scanning calorimetry (DSC).Results With the increase of storage duration, the compressive stress of the patellar ligament at 40% strain increased from 19 kPa to 112 kPa and then decreased to 57 kPa. SEM observation showed that the cross-linking of collagen fibers was initially strengthened and then weakened. DSC results showed that the enthalpy increased from 59.47 J/g to 67.10 J/g and then decreased to 54.43 J/g. The denaturation temperature increased from 67.62 ℃ to 77.28 ℃ and then decreased to 64.10 ℃.Conclusions When rabbit patellar ligament is stored at -20 ℃, with the increase of storage duration, the compressive stress of rabbit patellar ligament at 40% strain increases at first and then decreases. This change may be due to the variation of cross-linking level of collagen fibers. The stronger the cross-linking of collagen fibers, the stronger the compressive mechanical properties will be.

Storage duration of suspendedred blood cells affects the efficacy of blood transfusion in patients with aplastic anemia / 中国输血杂志

【Objective】 To study the impact of the storage duration of suspendedred blood cells(RBCs)on blood transfusion for patients with aplastic anemia. 【Methods】 76 occasions of blood transfusions for 36 patients with aplastic anemia, admitted to our hospital between 2017~2019, were observed. The effects of patient and donordemographics as well as storage duration on the efficacy of RBCs transfusion were analyzed using linear regression. 【Results】 Multivariate linear regression analysis revealed that the efficacy of RBCs transfusion was negatively correlated with the patient′s weight (P0.05) and -1.904 (95% CI: -3.750~-0.057; P<0.05) g/L, respectively, presenting a gradually decreasing trend. 【Conclusion】 Longer storage of RBCs has an impact on the efficacy of blood transfusion in patients with aplastic anemia.

Stability of lactoferrin and lysozyme in human milk at various temperatures and duration of storage

@#Introduction: Exclusive breastfeeding, especially in the first six months, is essential for infants as it provides nutrition and protection against various diseases. Colostrum, which is found in the first breast milk produced, contains various protective factors, such as lactoferrin and lysozyme. Human milk can be stored at room temperature, refrigerated, or kept frozen. Several factors affect the stability of the bioactive content in human milk, such as temperature and storage time. The aim of this study was to measure the stability of lactoferrin and lysozyme levels in human milk during the first six hours (h) at different temperatures and compare it with that of frozen human milk. Methods: Human milk samples were obtained from 11 breastfeeding mothers using certain criteria. The human milk was stored at room temperature and 4°C for 1, 3, and 6 h and classified as never frozen, while frozen human milk was stored at -20°C for 1, 3, and 6 days. Measurement of the lactoferrin and lysozyme levels was performed using enzyme-linked immunosorbent assay. Results: The results showed that storage at room temperature significantly reduced lactoferrin and lysozyme levels. Lactoferrin levels in frozen human milk did not significantly decrease during the first six days. Meanwhile, the lysozyme levels in frozen human milk decreased significantly. Conclusion: The levels of lactoferrin and lysozyme in frozen human milk stored for the first six days were more stable than those stored at room temperature and 4°C in the first 6 h.

Effect of temperature and time on the detection of calcium and magnesium in urinary sample storage / 中国职业医学

OBJECTIVE: To investigate the effect of temperature and time on the detection results of calcium and magnesium in urinary sample storage. METHODS: Urinary samples of 5 health volunteers were collected. The samples were stored in room temperature, 4 ℃ and-20 ℃ for different duration after sealed separately. A flame atomic absorption spectrometry was used to detect calcium and magnesium mass concentrations in the urinary samples. RESULTS: The variation rate of calcium and magnesium mass concentrations was <2.00% when urinary samples were stored at room temperature for 8 hours, the variation rate was <6.00% when samples were stored at 4 ℃ for 15 days, and it was <5.00% when samples were stored at-20 ℃ for 60 days. CONCLUSION: The temperature and time of urinary sample storage can affect the detection results of calcium and magnesium mass concentrations. Packing and storing samples at low temperature after collection as soon as possible is beneficial to ensure the accuracy of test results.

Transfusion-Related Acute Lung Injury after Stored Packed Red Blood Cell Transfusion: A Case Report / 대한구급학회지

Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related mortalities. Each type of blood product is likely to cause TRALI. Patients with TRALI present with dyspnea/respiratory distress and fever. The symptoms, signs and chest radiological findings in TRALI are similar to transfusion associated circulatory overload. Therefore, it is difficult to distinguish such from circulatory overloads. We report a case of TRALI in a 49-year-old woman after stored packed red blood cell transfusion. The patient developed hypoxemia and pulmonary edema after packed red blood cell transfusion during postoperative period. The patient completely recovered after an oxygen support for 3 days.

Effect of Storage Temperature and Durationon Potency of Botulinum Toxin / 대한피부과학회지

BACKGROUND: FDA recommend that botulinum toxin should be used within 4 hours after reconstruction. Because botulinum toxin is very expensive and also only small amounts of botulinum toxin are needed for one lesion, it should be used for several patients simultaneously to reduce cost. The reports on the decrease of potency according to storage temperature and duration were contradictory among the investigators. OBJECTIVE: The purpose of this study is to compare the change of the potency in various storage temperatures and duration and, to determine the optimal conditions for storage of botulinum toxin without potency reduction. METHODS: The potency of botulinum toxin was measured by the reduction rate of tension of the injected gastrocnemius muscle of Sprague-Dawley rats. The potency of botulinum toxin could be estimated through the comparison of the reduction rate of tension between two muscles; botulinum toxin injected muscle and normal saline injected control muscle, which was denoted as % paralysis. RESULTS: Botulinum toxin induced muscle paralysis in a dose-dependent manner. Muscle was paralysed by 9.8+/-0.6(mean+/-standard error), 10.2+/-2.7, 38.3+/-13.6, and 93.7+/-0.5% at 0(injected normal saline to both sides of gastrocnemius muscles of the same rat), 0.01, 0.1, and 1unit/0.1ml of fresh botulinum toxin injection, respectively. Percent paralyses by 1unit/0.1ml of stored botulinum toxin at 4degreeC and -20degreeC were 98.8+/-0.6% and 98.2+/-0.9% in 4 weeks, respectively. Percent paralyses by 0.1 unit/0.1 ml of stored botulinum toxin at 4degreeC and -20degreeC were 29.6+/-4.8% and 35.5+/-15.1% in 4 weeks, respectively. CONCLUSION: With these findings, the authors proved that if botulinum toxin is stored in refrigerator(4degreeC) or refreezer(-20degreeC) after reconstruction, it can be used without the decrease of its potency.