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 共查询到19条相似文献,搜索用时 15 毫秒
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Plant Cell, Tissue and Organ Culture (PCTOC) - Urtica dioica L. (Urticaceae), popularly known as nettle, is a medicinal plant used by the textile, food and pharmaceutical industry. The aim of the...  相似文献   

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Cysteine is important for protein synthesis, detoxification, and diverse metabolic functions. However, cysteine metabolism has been poorly described in fish, and the role of the therapeutic effect in pesticide toxicology on aquatic organisms is unknown. The aim of this study was to determine the effects of regular cysteine treatment on the hematology, biochemistry, apoptosis, oxidative DNA damage, and antioxidant parameters in fish blood after chemical application. Therefore, fish were exposed to cypermethrin for 2 weeks. Then two different concentrations of N‐acetylcysteine (NAC) were applied for a 4‐day treatment period and compared with the group of the self‐healing process. At the end of the treatment, the hematological index, blood biochemical parameters, paraoxonase (PON), arylesterase (ARE), and myeloperoxidase (MPO) activities in the fish blood samples were investigated. With regard to the hematological parameters, statistical differences were obtained except for mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) (P < 0.05). Enzyme activities (ARE, PON, and MPO), as well as some biochemical parameters (creatinin [Cre], alanine amino transferase, total glyceride, alkaline phosphatase, iron, calcium, low density lipoprotein‐cholesterol [LDL‐C], sodium, and potassium), were found to be importantly different among all groups at the P < 0.05 level, while 8‐hydroxydeoxyguanosine and caspase‐3 levels were determined to be high in the pesticide group but decreased significantly in NAC‐treated groups ( P < 0.05). According to the results of the study, acute cysteine treatment showed an ameliorative effect on the hematological index, biochemical parameters, PON, MPO, and ARE in the blood in the all the treatment group fish. The positive effect of NAC on protein synthesis, detoxification, and diverse metabolic functions against cypermethrin toxicity was more effective in 1.0 mM NAC. NAC has an important therapeutic effect on pesticide‐induced hematoxicity for fish in terms of all the data.  相似文献   

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Polyenylphosphatidylcholine is a choline-glycerophospholipid containing up to 80% of total fatty acids as linoleic acid and may be an important factor in ensuring normal functioning of cell membranes. We tested the effect of a polyenylphosphatidylcholine-supplemented diet and compared it with both a trilinolein-supplemented and a laboratory chow diet on the fatty acid composition, microviscosity, and delta-6-desaturase activity of liver microsomal membranes of 12-month-old rats, in the absence or presence of oxidative stress induced by adriamycin. Polyenylphosphatidylcholine- and trilinolein-supplemented diets showed a similar increase in linoleic acid content and delta-6-desaturase activity in liver microsomes, indicating that low amounts of linoleic acid are able to partially restore the enzyme activity in old rats, independent of the source of linoleic acid. After adriamycin treatment, delta-6-desaturase activity increased in polyenylphosphatidylcholine and trilinolein groups, indicating a protective mechanism against the damage induced by polyunsaturated fatty acid peroxidation. The measurement of malondialdehyde production showed a protective effect on adriamycin-induced lipid peroxidation by polyenylphosphatidylcholine supplementation only. Microsomal membrane microviscosity did not change independent of diet and adriamycin treatment, suggesting that the response of microsomes to lipid peroxidation might be the maintenance of a given membrane order. Administration of polyenylphosphatidylcholine can prevent or minimize the liver damage induced by adriamycin treatment.  相似文献   

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The plasma levels of apo B and apo E, and the level of hepatic and intestinal mRNA coding for these apolipoproteins were investigated in weanling male rats pair-fed for 6 wk with a control or copperdeficient diet. Plasma cholesterol, triglycerides, and phospholipids were significantly increased, and plasma apo B and apo E levels were also markedly increased in copper-deficient rats as compared to control rats. Copper deficiency significantly increased triglyceride levels and decreased cholesterol levels in the liver. No major differences in the levels of hepatic and intestinal apo B and apo E mRNA occurred between control and copper-deficient rats. These data imply that hypertriglyceridemia dn hypercholesterolemia owing to the copper deficiency are not accompanied by modifications in the gene expression at the mRNA level in the liver and intestine of the apolipoproteins studied.  相似文献   

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Endometriosis is a frequent and chronic illness in young women which could be defined by the existence of endometrial stroma and glands outside of the normal site of the lining of the uterus. It has painful symptoms. The advanced stage of endometriosis may lead to gynecological malignancies, such as ovarian cancer, and other complications, including infertility. However, its exact physiopathology is not well known. Recent studies have shown the possible roles of inflammation along with oxidative stress. Additionally, angiogenesis and apoptosis dysregulation contribute to endometriosis pathophysiology. Therapeutic strategies and continuing attempts, to conquer endometriosis should be done regarding molecular signaling pathways. Thus, the present review summarizes current studies and focuses on molecular mechanisms.  相似文献   

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Precursor B-cell acute lymphoblastic leukemia (B-ALL) is the most prevalent pediatric cancer. DNA methylation and changes in the microRNAs (miRNAs) expression are known to be important causes of B-ALL. Decitabine as a DNA methyltransferase inhibitor agent is able to induce hypomethylation in several tumor suppressor genes. Much evidence has proven BTG2, PPP1CA, and PTEN act as tumor suppressor genes in many malignancies. In this case control study, the messenger RNA (mRNA) expression of PPP1CA, BTG2, and PTEN genes using quantitative real-time polymerase chain reaction (rRT-PCR) in Nalm6 cell line and five patients suffer from ALL with mean age 5.6 years were determined in compare with seven normal healthy donors age and sex matched. qRT-PCR analysis revealed that the expression levels of PPP1CA, BTG2, and PTEN genes were significantly decreased in Nalm6 ([FC] = 0.46, [FC] = 0.046, [FC] = 0.54) and according to the Methylation-specific PCR (MSP) analysis, these genes were hypermethylated in Nalm6. In next step, the effects of decitabine treatment on the methylation and expression of these genes in association with changes in miR-125b, miR-17, and miR-181b expression levels were evaluated in optimal concentration 2.5 µM of decitabine. Our data showed that decitabine is able to restore the expression levels of aforementioned genes and downregulate expression levels of oncomiRs; including miR-125b, miR-17, and miR-181b in Nalm6 cell line. Therefore, it seems that decitabine can be used as a potential drug for the first line treatment of patients with B-ALL, but further in vivo investigation is necessary.  相似文献   

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Many viruses induce cell death and lysis as part of their replication and dissemination strategy, and in many cases features of apoptosis are observed. Attempts have been made to further increase productivity by prolonging cell survival via the over‐expression of anti‐apoptotic genes. Here, we extend the study to investigate the association between virus replication and apoptosis, pertinent to large‐scale vector production for gene therapy. Infection of an HEK293 cell line with a replication defective type‐5‐adenovirus expressing a GFP reporter (Ad5GFP) resulted in rapid decline in viability associated with increased virus titer. The over‐expression of bcl‐2 resulted in improved cell resistance to apoptosis and prolonged culture duration, but reduced virus specific and total productivity. In contrast, the over‐expression of pro‐caspase‐3 (Yama/CPP32/apopain) resulted in reduced cell survival but increased virus productivity. The treatment of infected cells with caspase inhibitors support the preposition that caspase‐3 dependent apoptosis, and to a lesser degree caspase‐9 dependent apoptosis, represent important steps in virus production, thus implicating the intrinsic apoptosis pathway in the production of adenovirus from HEK293 cells. The suppression of apoptosis by the over‐expression of XIAP (inhibitors of caspase family cell death proteases) further shows that caspase‐mediated activation plays an important role in virus infection and maturation. Biotechnol. Bioeng. 2009; 104: 752–765 © 2009 Wiley Periodicals, Inc.  相似文献   

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An experiment (complete randomised design) was conducted to investigate the effects of supplementing different molecular weights (MW) of chitooligosaccharide (COS) on intestinal morphology, selected microbial populations, volatile fatty acid (VFA) concentrations and the immune status of the weaned pig. A total of 28 piglets (24 days of age, 9.1 kg (± s.d. 0.80) live weight) were assigned to one of four dietary treatments for 8 days and then sacrificed. The treatments were (1) control diet (0 ppm COS), (2) control diet plus 5 to 10 kDa COS, (3) control diet plus 10 to 50 kDa COS and (4) control diet plus 50 to 100 kDa COS. The COS was included in dietary treatments at a rate of 250 mg/kg. Tissue samples were taken from the duodenum, jejunum and ileum for morphological measurements. Digesta samples were taken from the proximal colon to measure lactobacilli and Escherichia coli populations and digesta samples were taken from the caecum and proximal colon for VFA analysis. Gene expression levels for specific cytokines were investigated in colonic tissue of the pig. Supplementation of different MW of COS had no significant effect on pig performance during the post-weaning period (days 0 to 8; P > 0.05). The inclusion of COS at all MW in the diet significantly reduced faecal scores compared with the control treatment (P < 0.01). Pigs fed the 10 to 50 kDa COS had a higher villous height (P < 0.05) and villous height : crypt depth ratio (P < 0.05) in the duodenum and the jejunum compared with the control treatment. Pigs fed the 5 to 10 kDa COS had a lower lactobacilli population (P < 0.05) and E. coli population (P < 0.05) in the colon compared with the control group. Pigs offered the 5 to 10 kDa COS had significantly lower levels of acetic acid and valeric acid compared with the control group (P < 0.05). The inclusion of different MW of COS had no significant effect on the expression of the cytokines tumour necrosis factor-α, Interleukin (IL)-6, IL-8 and IL-10 in the gastro-intestinal tract of the weaned pig. The current results indicate that a lower MW of 5 to 10 kDa COS possessed an antibacterial activity, while the higher MW of 10 to 50 kDa was optimum for enhancing the intestinal structure.  相似文献   

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The endophytic fungus Piriformospora indica colonizes the roots of many plant species including Arabidopsis and promotes their performance, biomass, and seed production as well as resistance against biotic and abiotic stress. Imbalances in the symbiotic interaction such as uncontrolled fungal growth result in the loss of benefits for the plants and activation of defense responses against the microbe. We exposed Arabidopsis seedlings to a dense hyphal lawn of P. indica. The seedlings continue to grow, accumulate normal amounts of chlorophyll, and the photosynthetic parameters demonstrate that they perform well. In spite of high fungal doses around the roots, the fungal material inside the roots was not significantly higher when compared with roots that live in a beneficial symbiosis with P. indica. Fifteen defense- and stress-related genes including PR2, PR3, PAL2, and ERF1 are only moderately upregulated in the roots on the fungal lawn, and the seedlings did not accumulate H2O2/radical oxygen species. However, accumulation of anthocyanin in P. indica-exposed seedlings indicates stress symptoms. Furthermore, the jasmonic acid (JA) and jasmonic acid-isoleucine (JA-Ile) levels were increased in the roots, and consequently PDF1.2 and a newly characterized gene for a 2-oxoglurate and Fe2+-dependent oxygenase were upregulated more than 7-fold on the dense fungal lawn, in a JAR1- and EIN3-dependent manner. We conclude that growth of A. thaliana seedlings on high fungal doses of P. indica has little effect on the overall performance of the plants although elevated JA and JA-Ile levels in the roots induce a mild stress or defense response.  相似文献   

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Peroxiredoxins are redox-sensing multifunctional enzymes, among them peroxiredoxin 6 (Prx6) can neutralize the most broadest range of hydroperoxides and play an important role in maintaining the redox homeostasis of the cell. In the present study, radioprotective and signaling regulatory effects of Prx6 were demonstrated and characterized. Intravenously administered exogenous Prx6 protects the organism of mice from the destructive action of ionizing radiation in the lethal dose range of 5–10?Gy. Dose reduction factor of 1.4 Prx6 injection reduces the severity of radiation-induced leuko- and thrombopenia in irradiated animals, also preventing the destruction of epithelial cells in the small intestine. Injecting exogenous Prx6 also as its mutated form of Prx6–C47S lacking peroxidase activity affects the expression of genes involved in antioxidant response, DNA reparation, apoptosis and inflammatory processes, in bone marrow cells both in intact animals and in those subjected to ionizing radiation. The radioprotective properties of Prx6 are based, on the one hand, on the capability for ROS neutralization, and on the other hand – on the potentiality for activation of reparation processes of the cell under oxidative stress conditions. Prx6 can be considered as a potentially perspective radioprotective agent for the reduction of risks from the damaging action of ionizing radiation on the mammalian organism.  相似文献   

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Environmental constraints disturb plant metabolism and are often associated with photosynthetic impairments and yield reductions. Among them, low positive temperatures are of up most importance in tropical plant species, namely in Coffea spp. in which some acclimation ability has been reported. To further explain cold tolerance, the impacts on photosynthetic functioning and the expression of photosynthetic-related genes were analyzed. The experiments were carried out along a period of slow cold imposition (to allow acclimation), after chilling (4 °C) exposure and in the following rewarming period, using 1.5-year-old coffee seedlings of 5 genotypes with different cold sensitivity: Coffea canephora cv. Apoatã, Coffea arabica cv. Catuaí, Coffea dewevrei and 2 hybrids, Icatu (C. arabica × C. canephora) and Piatã (C. dewevrei × C. arabica). All genotypes suffered a significant leaf area loss only after chilling exposure, with Icatu showing the lowest impact, a first indication of a higher cold tolerance, contrasting with Apoatã and C. dewevrei. During cold exposure, net photosynthesis and Chl a fluorescence parameters were strongly affected in all genotypes, but stomatal limitations were not detected. However, the extent of mesophyll limitation, reflecting regulatory mechanisms and/or damage, was genotype dependent. Overnight retention of zeaxanthin was common to Coffea genotypes, but the accumulation of photoprotective pigments was highest in Icatu. That down-regulated photochemical events but efficiently protected the photosynthetic structures, as shown, e.g., by the lowest impacts on Amax and PSI activity and the strongest reinforcement of PSII activity, the latter possibly reflecting the presence of a photoprotective cycle around PSII in Icatu (and Catuaí). Concomitant to these protection mechanisms, Icatu was the sole genotype to present simultaneous upregulation of caCP22, caPI and caCytf, related to, respectively, PSII, PSI and to the complex Cytb6/f, which could promote better repair ability, contributing to the maintenance of efficient thylakoid functioning. We conclude that Icatu showed the best acclimation ability among the studied genotypes, mostly due to a better upregulation of photoprotection and repair mechanisms. We confirmed the presence of important variability in Coffea spp. that could be exploited in breeding programs, which should be assisted by useful markers of cold tolerance, namely the upregulation of antioxidative molecules, the expression of selected genes and PSI sensitivity.  相似文献   

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The purpose of this study was to investigate the effect of clomiphene citrate and human chorionic gonadotropin (HCG) on the structural changes, as well as the evaluation of the expression of cation channel sperm‐associated protein 1 (CatSper1), cation channel sperm‐associated protein 2 (CatSper2), luteinizing hormone/choriogonadotropin receptor (LHCGR), and steroidogenic factor 1 (SF1) genes in testicular tissue of rats. All rats divided into five groups as follows; G1 as the control group that received normal saline, G2 received olive oil, G3 received 100 IU/kg HCG, G4 received 5 mg/kg clomiphene citrate, and G5 received 5 mg/kg clomiphene citrate and 100 IU/kg HCG. At the end of the experiment period, Day 56, blood samples were taken and the serum was isolated. Then, histomorphometric analysis, hormonal assess, and real‐time polymerase chain reaction to measure the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were performed. The results showed that the concentrations of testosterone, follicle‐stimulating hormone, and luteinizing hormone were decreased in the G4 group, whereas these parameters were increased in the G3 group. A comparison of the sperm quality indicated a significant reduction in the quality of sperm cells in the G4 group compared with other groups. The quality of sperm was significantly enhanced in the G3 and G5 groups in comparison with the G1 group. Also, our findings demonstrated that the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were significantly elevated in the G3 group when compared with other experimental groups. According to the obtained results, it seems that clomiphene citrate reduces the process of spermatogenesis and the detrimental impacts of this compound would be neutralized by the administration of HCG.  相似文献   

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We have manipulated the chick limb bud by dorsoventrally inverting the ectoderm, by grafting the AER to the dorsal or ventral ectoderm and by insertion of an FGF-4 soaked heparin bead to the mesoderm. After dorso-ventral reversal of the ectoderm, Wnt-7a expression is autonomous from an early stage of limb development in the original dorsal ectoderm. Exogenous FGF-4 causes ectopic Wnt-7a expression and induces ectopic Shh. In addition, exogenous FGF-4 increases the thickness of cartilages and also shortens them, and both Bmp-2 and Bmp-4 may mediate this effect. The ectoderm outside the AER can regulate not only the dorso-ventral polarity of the underlying mesenchyme cells but also the cartilage formation, and both Bmp-2 and Bmp-4 may mediate this control.  相似文献   

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