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81.
Nitrotyrosine formation and apoptosis in rat models of ocular injury   总被引:2,自引:0,他引:2  
This study was performed to examine inducible nitric oxide synthase (NOS-2) expression, nitrotyrosine formation and apoptosis in rats with elevated intraocular pressure (IOP) and/or ocular inflammation. Ocular inflammation was induced via injection of intra-vitreal lipopolysaccharide (LPS) while IOP was elevated by episcleral vessel cauterization. Animals were randomized to one of the following conditions: elevated IOP, LPS, elevated IOP+LPS, and control. Immunohistochemical staining and western blot analysis of retinal lysates revealed NOS-2 and nitrotyrosine immunoreactivity in all disease groups. NOS-2 expression and protein nitration was significantly greater in rats with elevated IOP+LPS compared to elevated IOP, LPS, and control groups. Nitrite levels in the retina affirmed significantly increased levels of nitric oxide generation in LPS-treated rats with elevated IOP (346 ± 23.8 μM) vs LPS-treated, elevated IOP and control groups (195.6 ± 12.6, 130 ± 2.5 and 76.6 ± 15.6 μM, respectively). Retinal TUNEL staining showed apoptosis in all diseased groups. Percent of apoptotic cells was significantly greater in the elevated IOP+LPS group compared to LPS-treated or elevated IOP groups. Presented data illustrates that both elevated IOP and ocular inflammation augment NOS-2 expression, retinal protein nitration and apoptosis in rats.  相似文献   
82.
Akar T  Tunali S 《Bioresource technology》2006,97(15):1780-1787
The Pb(II) and Cu(II) biosorption characteristics of Aspergillus flavus fungal biomass were examined as a function of initial pH, contact time and initial metal ion concentration. Heat inactivated (killed) biomass was used in the determination of optimum conditions before investigating the performance of pretreated biosorbent. The maximum biosorption values were found to be 13.46 +/- 0.99 mg/g for Pb(II) and 10.82 +/- 1.46 mg/g for Cu(II) at pH 5.0 +/- 0.1 with an equilibrium time of 2 h. Detergent, sodium hydroxide and dimethyl sulfoxide pretreatments enhanced the biosorption capacity of biomass in comparison with the heat inactivated biomass. The biosorption data obtained under the optimum conditions were well described by the Freundlich isotherm model. Competitive biosorption of Pb(II) and Cu(II) ions was also investigated to determine the selectivity of the biomass. The results indicated that A. flavus is a suitable biosorbent for the removal of Pb(II) and Cu(II) ions from aqueous solution.  相似文献   
83.
Background: Chromosomal aberrations and instability of gene(s) are two factors related to the genetic instability of cancer cells. A loss of the tumor-suppressor function of the genes p16 and p53 is the most common event leading to the development of human cancers. Carcinoma of the lung is the leading cause of cancer deaths in the world. Chromosomal abnormalities in lung cancer may provide a valuable clue to the identification of target loci and culminate in a successful search for the major genes. The aim of this study was to investigate (i) alterations of the p16 and p53 genes and (ii) chromosomal aberrations in patients with small cell and non-small cell lung cancer by fluorescence in situ hybridization (FISH) and cytogenetic studies. Methods: We carried out cytogenetic analysis by Giemsa-banding in 18 cases. FISH probes for the p16 and p53 genes were also used on interphase nuclei to screen the alterations in these genes in lung cancer (LC).Results: We observed a high frequency of losses of the p16 – in 8/18 (44%) – and p53 – in 7/18 (39%) – genes in the cases with LC. A total of 18 patients showed predominantly numerical and structural aberrations. Among these two types, structural aberrations predominated and usually consisted of deletions, breaks, and fragilities in various chromosomes. Both structural and numerical changes were observed in almost all patients. Chromosomes 3 and 1 were found to be most frequently involved in structural abnormalities, followed by chromosomes 6, 9, and 8. Autosomal aneuploidies were also observed to be the most frequent (chromosomes 22, 19, 18, 20, 9, and 17), followed by those of the X and Y chromosomes. The expression of fragile sites was also found to be significantly higher in seven chromosomal regions: 3p14, 1q21, 1q12, 6q26, 9q13, 8q22, and 8q24. Conclusion: Our data confirmed that DNA damage and genomic instability may be factors contributing to the mutation profile and development of lung cancer. The patients who developed lung cancer showed a high frequency of loss of both p16 and p53, in addition to chromosomal aberrations. Tobacco could be a major carcinogenic factor in lung-cancer progression. The loss of p16 and p53, and increased incidence of autosomal aneuploidy and chromatid breaks, along with other chromosomal alterations, can contribute to the progression of the disease.  相似文献   
84.
Amino Acids - Our aim in this study was to measure serum levels of methylarginines and related metabolites in patients with ankylosing spondylitis (AS), moreover, to investigate the relationship...  相似文献   
85.
The Notch gene encodes an evolutionarily conserved cell surface receptor that generates regulatory signals based on interactions between neighboring cells. In Drosophila embryos it is normally expressed at a low level due to strong negative regulation. When this negative regulation is abrogated neurogenesis in the ventral region is suppressed, the development of lateral epidermis is severely disrupted, and the dorsal aminoserosa is expanded. Of these phenotypes only the anti-neurogenic phenotype could be linked to excess canonical Notch signaling. The other phenotypes were linked to high levels of Notch protein expression at the surface of cells in the lateral regions indicating that a non-canonical Notch signaling activity normally functions in these regions. Results of our studies reported here provide evidence. They show that Notch activities are inextricably linked to that of Pkc98E, the homolog of mammalian PKCδ. Notch and Pkc98E up-regulate the levels of the phosphorylated form of IκBCactus, a negative regulator of Toll signaling, and Mothers against dpp (MAD), an effector of Dpp signaling. Our data suggest that in the lateral regions of the Drosophila embryos Notch activity, in conjunction with Pkc98E activity, is used to form the slopes of the opposing gradients of Toll and Dpp signaling that specify cell fates along the dorso-ventral axis.  相似文献   
86.
In this study, wheat straw was pretreated with a microfluidizer to improve its enzymatic hydrolysis and ethanol yields. The pretreatment was performed at various pressures (500, 1000, and 1500 bar) and solid loadings (1, 2, and 3%). The microfluidized biomass was then subjected to hydrolysis and simultaneous saccharification and co-fermentation (SSCF) experiments at different enzyme loadings (5, 10, and 15 FPU/g dry wheat straw) using a mutant yeast. The results indicated that the microfluidization method alters the structure of biomass and leads to a reduction in lignin content. The samples pretreated at 1% solid loading contained the minimum lignin concentration and provided the maximum sugar and ethanol yields. These results signified that the microfluidization method is more effective on biomass at low solid loadings. The process conditions were optimized for higher ethanol and sugar yields using response surface methodology (RSM). The optimum pressure and solid and enzyme loadings were found as 1500 bar, 1%, and 15 FPU/g dry wheat straw, respectively. The yields obtained at this condition were 82%, 94%, and 65% for glucose, xylose, and ethanol, respectively. High sugar yields implied that microfluidization is an effective pretreatment method for cellulosic ethanol production. On the other hand, low ethanol yield may indicate that the microorganism was sensitive to inhibitory compounds present in the fermentation medium.  相似文献   
87.
Tinea capitis is a dermatophyte infection of the scalp that is most often seen in prepubescent children. In this investigation, we examined the prevalence of tinea capitis and symptom-free colonization of the scalp with dermatophytes in 786 pre- and postmenopausal women aged 12–84 years. Scalp samples were collected from all participants by cytobrush or hairbrush, and cultures were then grown from these samples on Sabouraud glucose agar. No participant was diagnosed with tinea capitis; however, one 43-year-old patient (0.1%) was positive for a “scalp carriage” related to anthropophilic Trichophyton rubrum, as detected using a hairbrush. The internal transcribed spacer (ITS) regions of the isolate were sequenced, and the assembled DNA sequences were examined using the basic BLAST (nucleotide–nucleotide) software of the National Center for Biotechnology Information Web database. This patient was followed up without any antimycotic treatment, and after 4 weeks, mycological clearance was documented. In addition, the contacts and environment at home were screened, where all fungal cultures were sterile. To the best of our knowledge, this study is the first report of a “scalp carriage” related to a cosmopolitan fungus, T. rubrum.  相似文献   
88.
A newly series of 4-(phenylurenyl)chalcone (4aj) and 4′-(phenylurenyl/thiourenyl)chalcone (9al) derivatives were synthesized and their inhibitory effects on the diphenolase activity of banana tyrosinase were evaluated. Tyrosinase has been purified from banana on an affinity gel comprised of Sepharose 4B-l-tyrosine-p-aminobenzoic acid. The result showed that 4aj inhibited the PPO enzyme activity. Conversely, 9ah and 9il showed activator effect on tyrosinase enzyme activity.  相似文献   
89.
The vascular endothelial dysfunction has been implicated in the pathogenesis of migraine. Oxidized low‐density lipoprotein (ox‐LDL) may impair endothelial function. Paraoxonase‐1 (PON‐1) prevents oxidative modification of LDL cholesterol (LDL‐C). So we investigated serum PON‐1 and arylesterase (ARE) activities, PON‐1 55 L/M and 192Q/R polymorphisms and the serum lipid profile in patients with migraine. Biochemical parameters and PON‐1 polymorphism analyses were assessed in 104 patients with migraine and 86 healthy subjects. Ox‐LDL was detected by ELISA, and polymorphisms were determined using PCR–restriction fragment length polymorphism analysis. Patients with migraine had lower PON‐1 and ARE activities (p < 0·001, for both) and higher ox‐LDL and LDL‐C levels (p < 0·001, for both) and ox‐LDL: LDL‐C ratio (p < 0·005) than the controls. The genotype distribution and the allele frequencies for PON‐1 55 L/M and 192Q/R polymorphisms were not different among the study populations. The results of our current study indicate that migrainous patients have decreased serum PON‐1 and ARE activities and increased serum ox‐LDL levels, which may have a clinical importance in the treatment of migraine. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
90.
The effects of vitamin E and Hippophea rhamnoides L. extract (HRe‐1) on nicotine‐induced oxidative stress in rat heart were investigated. There were eight rats per group and supplementation period was 3 weeks. The groups were: nicotine [0.5 mg kg?1day?1, intraperitoneal (i.p.)]; nicotine plus vitamin E [75 mg kg?1day?1, intragastric (i.g.)]; nicotine plus HRe‐1 (250 mg kg?1day?1, i.g.); and the control group (receiving only vehicles). Nicotine increased the malondialdehyde level, which was prevented by both vitamin E and HRe‐1. Glutathione peroxidase (GPx) activity in nicotine plus vitamin E supplemented group was higher than the others. Glutathione S‐transferase (GST) activity in nicotine plus HRe‐1 supplemented group was increased compared with the control group. Catalase activity was higher in nicotine group compared with others. GPx activity in nicotine plus vitamin E supplemented group was elevated compared with the others. Total and non‐enzymatic superoxide scavenger activities in nicotine plus vitamin E supplemented group were lower than nicotine plus HRe‐1 supplemented group. Superoxide dismutase (SOD) activity was higher in nicotine plus HRe‐1 supplemented group compared with others. Glutathione reductase activity and nitric oxide level were not affected. Increased SOD and GST activities might have taken part in the prevention of nicotine‐induced oxidative stress in HRe‐1 supplemented group in rat heart. Flavonols such as quercetin, and isorahmnetin, tocopherols such as α‐tocopherol and β‐tocopherol and carotenoids such as α‐carotene and β‐carotene, reported to be present in H. rhamnoides L. extracts may be responsible for the antioxidant effects of this plant extract. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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