Development of HLA-matched vascular grafts utilizing decellularized human umbilical artery

Worldwide, there is a great need of small diameter vascular grafts that can be used in human disorders such as cardiovascular and peripheral vascular disease. Until now, severe adverse reactions are caused from the use of synthetic or animal derived grafts, while the use of autologous vessels is restricted only in a small number of patients. The limited availability of the vessels might be resolved by the use of HLA-matched vascular grafts utilizing the decellularized human umbilical arteries. In this study, human umbilical arteries were decellularized and then repopulated with Mesenchymal Stem Cells. The HLA-genotype of the repopulated grafts, analyzed by Next Generation Sequencing technology, indicated their successful production. The HLA-matched vascular grafts could be generated efficiently and might be used in personalized medicine.     

Assessment of naturally occurring covalent and total dimer levels in human IgG1 and IgG2

Antibody dimers, two self-associated monomers, have been detected on both recombinantly expressed and endogenous human IgG proteins. Nearly 10 years ago, Yoo et al. (2003) described low levels of IgG2 covalent dimer, in human serum, but did not quantify the levels. Here we quantify the total and covalent dimer levels of IgG2 and IgG1 in human blood, and study the origin of covalent dimer formation. Low levels (<1%) of total IgG1 and IgG2 dimers were measured in freshly prepared human plasma. Both IgG1 and IgG2 covalent dimers were also found in plasma. Whereas IgG1 covalent dimer levels were significantly reduced by steps intended to eliminate artifacts during sample preparation, IgG2 covalent dimer levels remain stable in such conditions. About 0.4% of IgG2 in plasma was in a covalent dimer form, yet very little (<0.03%) of IgG1 covalent dimer could be considered naturally occurring. IgG2 dimer also formed in vitro under conditions designed to mimic those in blood, suggesting that formation occurs in vivo during circulation. Thus, small amounts of covalent IgG2 dimer do appear to form naturally.     

Evaluation of EDTA and fish skin extract in primary culture of fish liver cells

The isolation, primary culture and attachment of liver cells to the substratum from a tropical catfish (Heteropneustes fossilis) using ethylenediaminetetraacetic acid (EDTA) as isolating agent of liver cells and skin extract (SE) from fish as attachment substrate for the primary culture of liver cells has been standardised. A suitable temperature for such cultures has also been determined. Attachment efficiency of the liver cells in culture and their intracellular lactate dehydrogenase (LDH) activity have been taken as parameters for characterization of the primary culture. Disaggregation of liver cells with EDTA is very potent to isolate substantial rumber of cells from the liver of H. fossilis. An ideal concentration of EDTA for liver cell isolation has been standardized. Matrix prepared from carp and catfish skin at different pH (2.0, 4.0, 6.0 and 8.0) were also evaluated for liver cell culture by considering the attachment efficiency of the cells over the substratum as well as retention of intracellular LDH enzyme after 48 hours of seeding. Matrix of carp skin was compared with that of catfish as suitable substrate for primary culture of fish liver cells. It has been found that the SE prepared at pH 4.0, both from carp and catfish skin, performed better than those at other pHs. At the same time, the matrix of carp skin was found to be better than that of catfish skin. Cultures were incubated separately at 17 and 23 °C in air atmosphere. Incubation temperature at 23 °C was found to be more suitable than that at 17 °C. The percent of detached/unattached cells showed only marginal variation between two temperatures but LDH-activity recorded drastic reduction (between 50 to 75%) depending upon the pH of the matrix during preparation. Our finding establishes despensibility of enzyme (collagenase/trypsin) for cell isolation in catfish. Our studies also exhibit that carp skin extract performs better than catfish skin extract in terms of attachment efficiency as well as intracellular LDH activity. This study indicates that no species/generic barrier exists in matrix between catfish and carp.     

Mechanism of suppression of physiological functions in hypothermia and means for their stimulation without body warming

Cold-suppressed thermoregulatory reactions and respiration in rats in deep hypothermia (rectal body temperature (25–22°C) were shown to be stimulated by injecting disodium ethylenediaminetetraacetic acid (EDTA) solution into the blood stream of cold rats at a dose of 16.5 mg/100 g (0.0045 mmol/100 g). EDTA binds Ca²⁺ ions in the blood, forming complexes. Increases in cold shivering and pulmonary respiration (by 5 min after the start of administration) coincided with a reduction in the blood Ca²⁺ concentration by 42–45% of normal. By 15 min after the start of the EDTA injection, the blood Ca²⁺ concentration returned to the normal level present in cold rats before EDTA treatment. This was accompanied by suppression of cold shivering and pulmonary respiration. Repeated injection of EDTA into the blood stream produced a new drop in blood Ca²⁺ and repeated stimulation of cold shivering and pulmonary respiration. __________ Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 92, No. 11, pp. 1373–1381, November, 2006.     

Hepatoprotective effects of Artemisiae Capillaris Herba and Picrorrhiza Rhizoma combinations on carbon tetrachloride–induced subacute liver damage in rats

The hepatoprotective properties of Artemisiae Capillaris Herba (AC) and Picrorrhiza Rhizoma (PR) are well known. The aim of this study was to determine the optimal composition of AC and PR mixtures for better complimentary or alternative regimens in reducing the level of hepatic fibrosis. Ten weeks of carbon tetrachloride injections caused subacute hepatic damage, manifested as significantly less body weight gain and hepatic protein content, and a higher liver weight, serum aspartate aminotransferase and alanine aminotransferase levels, hepatic malondialdehyde (an index for lipid peroxidation), and hydroxyproline (an index for collagen synthesis) concentrations. The carbon tetrachloride–induced toxic effects were inhibited by 11 different AC/PR mixtures as well as the single AC or PR treatment. More favorable effects were detected in all mixed-formulation groups compared with the AC or PR single formulations. Moreover, the AC/PR 2:1 formulation showed the most favorable hepatoprotective activity. The AC and PR mixtures showed good synergic hepatoprotective activity that was attributed to increasing free-radical scavenging ability. Among the 11 types of mixed formula tested in this study, the AC/PR 2:1 formulation had the most impressive synergic effects on inhibiting the subacute hepatic damage induced by carbon tetrachloride in rats and showed more favorable effects than with an equal dose of silymarin.     

多聚赖氨酸与EDTA的交联物清除晶状体上皮细胞的实验研究

目的研究多聚赖氨酸与乙二胺四乙酸二钠(EDTA)的交联物清除晶状体超声乳化吸出术中摘出的人晶状体囊的晶状体上皮细胞的效果。方法利用碳化二亚胺将EDTA与多聚赖氨酸结合起来,制成交联物——PLE。收集白内障晶状体超声乳化吸出术中取出的晶状体前囊24个,将其随机分为4组,分别用10mmol/LEDTA、PLE(含10mmol/LEDTA)、多聚赖氨酸(含10mmol/LNH2-)及生理盐水进行处理。将各组晶状体前囊进行HE染色、显微镜下观察。采集图像,利用图像分析系统进行分析并计算清除率。结果PLE组的清除率与EDTA组相比,差异有统计学意义(P<0.01)。结论PLE清除晶状体上皮细胞的效果明显强于EDTA。     

Kaempferol induces apoptosis in human lung non-small carcinoma cells accompanied by an induction of antioxidant enzymes.

Kaempferol (3, 4',5,7-tetrahydroxyflavone) is one of the most commonly found dietary flavonols. The biological and pharmacological effects of kaempferol may depend upon its behavior as either an antioxidant or a prooxidant. However, the clear biological effects of prooxidant or antioxidant character of kaempferol has not been clarified yet. The overall objective of the present study is to explore the role of prooxidant or antioxidant in kaempferol-induced cell toxicity. In this paper, we have proved that antioxidant pathway may be involved in kaempferol induces H460 cell apoptosis. Kaempferol-induced H460 cell apoptosis is a typical apoptosis that was accompanied by a significant DNA condensation and increasing intracellular ATP levels. Kaempferol-induced apoptosis is related to its ability to change the expression of apoptotic markers, such as caspase-3 (caspase-dependent) and AIF (caspase-independent). The overexpression of antioxidant enzyme Mn SOD protein levels, which was promoted to a new type tumor suppressor gene in several human cancer cells recently, may be an important role in kaempferol-induced H460 cell apoptosis.     

Toxicological assessment of a particulate yeast (1,3/1,6)-beta-D-glucan in rats.

This study investigates the toxicity of WGP 3-6, a yeast-derived beta-glucan ingredient, during single-dose acute and sub-chronic toxicity studies in rats. For the acute study, Fisher-344 rats were administered WGP 3-6 via gavage at a dose of 2000 mg/kg body weight, and any evidence of toxicity was monitored over a 14-day period. WGP 3-6 was well tolerated, indicating that the LD(50) value is greater than 2000 mg/kg body weight. For the sub-chronic study, Fisher-344 rats (10/sex/group) were randomly allocated to receive daily gavage treatment with WGP 3-6 at doses of 0, 2, 33.3, or 100 mg/kg body weight. Control and high-dose satellite recovery groups of each sex also were included. Full toxicological monitoring and endpoint investigations were performed throughout and upon completion of the study. No negative effects on animal weights or food consumption attributable to WGP 3-6 were evident at any dose. In addition, no mortality, clinical pathology, functional/behavioral, microscopic, or gross observations indicating toxicity were observed. Sporadic changes in some biochemical and hematological parameters were observed; however, since the effects were within the physiological ranges in historical controls, were not dose-responsive, or were not observed in both sexes, they were determined to be of no toxicological significance. In conclusion, no adverse or toxic effects were observed after subchronic oral administration of 2, 33.3, or 100mg/kg body weight/day of WGP 3-6 in Fisher-344 rats, and therefore, a no observed adverse effect level (NOAEL) of 100 mg/kg body weight/day, the highest dose tested, was determined.     

32例EDTA依赖性血小板减少症患者浅析

目的 探讨EDTA-K2抗凝血时导致血小板假性减少现象的原因.方法 对采用全自动五分类血细胞分析仪检洲血小板低于100×109/L的标本,进行涂片镜检,如镜下血小板分布与仪器计数不符,则重新抽枸橼酸钠抗凝血进行血小板计数及手工血小板计数进行复检,并涂片镜检观察血小板分布情况.结果 32名患者复检及手工计数结果 与使用EDTA-K2抗凝血血小板计数结果 明显不同.结论 EDTA-K2抗凝血偶尔可导致血小板聚集,引起血小板检测结果 假性减少,在临床检验工作中应引起重视并加强镜检复核.