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1.
BackgroundThe aim of this study was to determine the levels of lipid peroxidation (MDA) and antioxidants such as reduced glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD) in the blood serum of patients with cirrhosis and liver transplantation.MethodsIn this study, serum malondialdehyde acid (MDA) levels, superoxide dismutase (SOD), reduced glutathione (GSH), and catalase (CAT) activities were measured spectrophotometrically and compared to the results of the healthy control group.ResultsSOD, CAT and GSH activities were significantly decreased in the patient groups compared to the healthy control group (p<0.05). MDA levels were significantly higher in the patient group compared to the healthy control group (p <0.05).ConclusionsIn conclusion, this study demonstrated that oxidative stress may play an important role in the development of liver cirrhosis and in liver transplantation. This study is the first one to show how MDA, SOD, CAT and GSH levels change in liver cirrhosis and liver transplantation, while further studies are essential to investigate antioxidant enzymes and oxidative stress status in patients with cirrhosis and liver transplantation.  相似文献   
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Pulse amplitude modulation fluorescence was used to investigate whether abscisic acid (ABA) pretreatment increases the desiccation tolerance of photosynthesis in the moss Atrichum undulatum. In unstressed plants, ABA pretreatment decreased the F V/F m ratio, largely as a result of an increase in F o. This indicated a reduction in energy transfer between LHCII and PSII, possibly hardening the moss to subsequent stress by reducing the production of the reactive oxygen species near PSII. During desiccation, F 0, F m, F v/F m, PSII, and NPQ and F 0 quenching declined in ABA-treated and nontreated mosses. However, during rehydration, F 0, F m, F v/F m, and PSII recovered faster in ABA-treated plants, suggesting that ABA improved the tolerance of photosystem II to desiccation. NPQ increased upon rehydration in mosses from both treatments, but much more rapidly in ABA-treated plants; during the first hour of rehydration, NPQ was two-fold greater in plants treated with ABA. F 0quenching followed a similar pattern, indicating that ABA treatment stimulated zeaxanthin-based quenching. The implications of these results for the mechanisms of ABA-induced desiccation tolerance in A. undulatum are discussed.  相似文献   
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Imazalil (IMA), a commonly used fungicide in both agricultural and clinical domains, is suspected to produce serious toxic effects in vertebrates. In recent years, a number of studies have suggested that lichens might be easily accessible sources of natural drugs that could be used as a possible food supplement. Extensive research is being performed to explore the importance of lichen species, which are known to contain a variety of pharmacological active compounds. In this context, the antigenotoxic effect of aqueous Dermatocarpon intestiniforme (K?rber) Hasse. extract (DIE) was studied against the genotoxic damage induced by IMA on cultured human lymphocytes (n = 6) using chromosomal aberration (CA) and micronucleus (MN) as cytogenetic endpoints. Human peripheral lymphocytes were treated in vitro with varying concentrations of DIE (0, 25, 50 and 100 μg/ml), tested in combination with IMA (336 μg/ml). DIE alone were not genotoxic and when combined with IMA treatment, it reduced the frequency of CAs and the rate of MNs. A clear dose-dependent decrease in the genotoxic damage of IMA was observed, suggesting a genoprotective role of DIE. The results of the present study suggest that this plant extract per se does not have a genotoxic potential, but can alleviate the genotoxicity of IMA on cultured human lymphocytes. In conclusion our findings may have an important application for the protection of cultured human lymphocyte from the genetic damage and side effects induced by medical and agricultural chemicals hazardous for people.  相似文献   
4.
In this study, R(+)‐α‐methylbenzylamine‐modified magnetic chiral sorbent was synthesized and assessed as a new enantioselective solid phase sorbent for separation of mandelic acid enantiomers from aqueous solutions. The chemical structures and magnetic properties of the new sorbent were characterized by vibrating sample magnetometry, transmission electron microscopy, Fourier transform infrared spectroscopy, and dynamic light scattering. The effects of different variables such as the initial concentration of racemic mandelic acid, dosage of sorbent, and contact time upon sorption characteristics of mandelic acid enantiomers on magnetic chiral sorbent were investigated. The sorption of mandelic acid enantiomers followed a pseudo‐second‐order reaction and equilibrium experiments were well fitted to a Langmuir isotherm model. The maximum adsorption capacity of racemic mandelic acid on to the magnetic chiral sorbent was found to be 405 mg g?1. The magnetic chiral sorbent has a greater affinity for (S)‐(+)‐mandelic acid compared to (R)‐(?)‐mandelic acid. The optimum resolution was achieved with 10 mL 30 mM of racemic mandelic acid and 110 mg of magnetic chiral sorbent. The best percent enantiomeric excess values (up to 64%) were obtained by use of a chiralpak AD‐H column. Chirality 27:835–842, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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Biomechanics and Modeling in Mechanobiology - Living soft tissues appear to promote the development and maintenance of a preferred mechanical state within a defined tolerance around a so-called set...  相似文献   
7.
Polychlorinated biphenyls (PCBs) are persistent environmental pollutants. This study compared effects of two PCB mixtures, Aroclors 1221 (A1221) and 1254 (A1254) on serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), urea, creatinine and uric acid in female rats. Histopathological changes in the liver and kidney were also examined. A group of adult Wistar rats served as controls. Groups II and III were subcutaneously injected with A1221 and A1254 at 10 mg/kg every other day for 6 weeks. At the end of this period, all animals were decapitated and blood samples were collected. Serum urea, creatinine, uric acid, ALT, AST and ALP levels were determined. Liver and kidney were collected for histopathological examination. They were fixed in formaldehyde and processed for light microscopy. Both A1221 and 1254 significantly elevated serum ALT (p < 0.05) and AST (p < 0.01) levels compared to the control group. Serum ALP values were significantly increased by A1221 (p < 0.05), but they were unaffected in the A1254 group. Treatment with both A1221 and A1254 significantly increased serum levels of urea (p < 0.05), creatinine (p < 0.01) and uric acid (except in the A1221 group; p < 0.005). Distinct histopathological changes including renal corpuscular atrophy, peritubular vascular congestion and dilated cortical tubules, sinusoidal dilatation, congestion and mononuclear cell infiltration were observed. These findings suggest that PCBs may cause nephrotoxicity and hepatotoxicity in female rats.  相似文献   
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WNT signaling pathway plays important roles in reproductive events. Aims were to (1) determine presence of WNT genes and their antagonists in equine endometrium; and (2) to evaluate their expression profiles during early pregnancy. Endometrial biopsies were obtained from mares on day of ovulation (d0, n=4) and on days of 14 (P14, n=4), 18 (P18, n=4), 22 (P22, n=4) of early pregnancy. Biopsies were also collected from cyclic mares during late diestrus (LD, on day of 13.5-14, n=4) and after luteolysis in estrus phase (AL, on day of 17.5-18, n=4) of the cycle. PCR was used to detect expression of genes studied and then relative expression levels were quantified using real-time PCR analysis. A mixed model was fitted on the normalized data and least significant difference test (α=0.05) was employed. Eleven WNT genes (WNT2, WNT2B, WNT4, WNT5A, WNT5B, WNT7A, WNT8A, WNT9B, WNT10B, WNT11 and WNT16) and their antagonists (SFRP1, SFRP2, SFRP5, DKK1, DKK2 and WIF-1) were detected in equine endometrium. Compared to d0, WNT2, WNT5B, WNT7A and SFRP1 expressions were downregulated by the pregnancy while DKK1 was upregulated. WNT5A, WNT11 and WIF-1 were upregulated on P14 and P18, but WNT2B increased only on P14. When LD and P14 were compared, level of WNT8A decreased on P14 while increase in WNT4 level on P14 was slightly significant (P<0.06). Levels of WNT7A and SFRP1 decreased while DKK1 and WIF-1 increased by the pregnancy on P18 compared to AL. Moreover, WNT2B, WNT5A, WNT9B, WNT10B, WNT11, WNT16 DKK1 and WIF-1 were upregulated on LD compared to AL whereas WNT4, WNT7A, SFRP1 were downregulated. In conclusion, the results demonstrate that WNT genes and their antagonists appear to be regulated during early pregnancy in equine endometrium possibly due to embryonic factors and/or maternal progesterone.  相似文献   
10.
Ghrelin belongs to the family of a gut-brain hormone that promotes food intake and controls energy balance. Recently, it has also been shown to regulate bone formation directly. Dental tissue shares several functional, developmental and anatomical similarities with bone, and in the present study we have investigated the presence of ghrelin in 44 human teeth using immunocytochemistry and radioimmunoassay. Both methods showed that the hormone is present in canines and molars, mainly in the odontoblasts but also in the pulp. Ghrelin could potentially play interesting physiological roles in teeth.  相似文献   
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