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51.
Molecular Biology Reports - Carbonic anhydrases (CAs) play a significant role in maintaining pH balance by catalyzing the conversion of carbon dioxide to bicarbonate. The regulation of pH is...  相似文献   
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Biomechanics and Modeling in Mechanobiology - The present study has sought to investigate the fluid characteristic and mechanical properties of trabecular bone using fluid–structure...  相似文献   
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Landscape and Ecological Engineering - Riparian vegetation is constantly subjected to environmental stresses and reactive oxygen species (ROS) are generated in the plant tissue due to the stress....  相似文献   
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Despite the fact that the use of antibiotics is increasing worldwide, it is clear that antibiotics can lead to oxidative stress. This is the first study to make a comparison of the impact of frequently prescribed antibiotics, including amoxicillin, gentamicin, and cefazolin sodium, on the gene, protein, and activity of glutathione reductase (GR), which is one of the primary antioxidant enzymes, in mouse liver and kidney tissues. First, the GR enzyme was purified by the 2′,5′‐ADP Sepharose 4B affinity chromatography with a specific activity of 84.615 EU/mg protein and 9.63 EU/mg protein from the mouse liver and kidney, respectively. The in vitro inhibitory effects of the antibiotics in question was determined. While cefazolin sodium did not exhibit any inhibitory effect, gentamicin and amoxicillin inhibited GR activity in both tissues. Furthermore, the in vivo effects of these drugs were investigated, and amoxicillin and cefazolin sodium‐inhibited GR activity in both liver and kidney tissues, while gentamicin did not have any effect on the kidney. Besides, while gentamicin downregulated and cefazolin sodium upregulated Gr gene expression, amoxicillin did not alter it. Protein expression was only affected by the administration of cefazolin sodium in the kidney. This study is important as it demonstrates that while amoxicillin and gentamicin showed parallel effects on the GR activity in liver and kidney tissues both in vitro and in vivo, cefazolin sodium had a very strong effect on hepatic and renal GR in vivo. Furthermore, the antibiotics used in this study induced oxidative stress in both tissues.  相似文献   
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HIF-1α regulated genes are mainly responsible for tumour resistance to radiation- and chemo-therapy. Among these genes, carbonic anhydrase isoform IX (CA9) is highly over expressed in many types of cancer especially in high grade brain cancer like Glioblastoma (GBM). Inhibition of the enzymatic activity by application of specific chemical CA9 inhibitor sulphonamides (CAI) like Acetazolamide (Aza.), the new sulfonamide derivative carbonic anhydrase inhibitor (SU.D2) or indirect inhibitors like the HIF-1α inhibitor Chetomin or molecular inhibitors like CA9-siRNA are leading to an inhibition of the functional role of CA9 during tumorigenesis. Human GBM cells were treated with in vitro hypoxia (1, 6, or 24 h at 0.1%, O2). Aza. application was at a range between 250 and 8000 nM and the HIF-1α inhibitor Chetomin at a concentration range of 150–500 nM. Cell culture plates were incubated for 24 h under hypoxia (0.1% O2). Further, CA9-siRNA constructs were transiently transfected into GBM cells exposed to extreme hypoxic aeration conditions. CA9 protein expression level was detectable in a cell-type specific manner under normoxic conditions. Whereas U87-MG exhibited a strong aerobic expression, U251 and U373 displayed moderate and GaMG very weak normoxic CA9 protein bands. Aza. as well as SU.D2 displayed inhibitory characteristics to hypoxia induced CA9 expression in the four GBM cell lines for 24 h of hypoxia (0.1% O2) at concentrations between 3500 and 8000 nM, on both the protein and mRNA level. Parallel experiments using CA9-siRNA confirmed these results. Application of 150–500 nM of the glycolysis inhibitor Chetomin under similar oxygenation conditions led to a sharply reduced expression of both CA IX protein and CA9 mRNA levels, indicating a clear glucose availability involvement for the hypoxic HIF-1α and CA9 expression in GBM cells. Hypoxia significantly influences the behaviour of human tumour cells by activation of genes involved in the adaptation to hypoxic stress. The main objective in malignant GBM therapy is either to eradicate the tumour or to convert it into a controlled, quiescent chronic disease. Aza., SU.D2, Chetomin or CA9-siRNA possesses functional CA9 inhibitory characteristics when applied against human cancers with hypoxic regions like GBM. They may be used as alternative or in conjunction with other direct inhibitors possessing similar functionality, thereby rendering them as potential optimal tools for the development of an optimized therapy in human brain cancer treatment.  相似文献   
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To identify Fusarium species associated with diseases of root and basal plate of onion, surveys were conducted in seven provinces of Turkey in 2007. Samplings were performed in 223 fields, and 332 isolates belonging to 7 Fusarium spp. were obtained. The isolates were identified as Foxysporum, Fsolani, Facuminatum, Fequiseti, Fproliferatum, Fredolens, and Fculmorum based on morphological and cultural characteristics. Also, species‐specific primers were used to confirm the identity of Fusarium species. Foxysporum was the most commonly isolated species, comprising 66.57% of the total Fusarium species. Fredolens was identified for the first time in onion‐growing areas of Turkey. Selected isolates of each species were evaluated for their aggressiveness on onion plant. Foxysporum, Fsolani, Facuminatum, Fproliferatum, and Fredolens were highly pathogenic, causing severe damping‐off on onion plants cv. Texas Early Grano. Inter‐simple sequence repeats (ISSR) markers revealed a high degree of intra‐ and interspecific polymorphisms among Fusarium spp.  相似文献   
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Purpose

To investigate the association between Apparent Diffusion Coefficient (ADC) values and cell cycle and proliferative biomarkers (p53, p21, Ki67,) in order to establish its potential role as a noninvasive biomarker for prediction of cell cycle, proliferative activity and biological aggressiveness in bladder cancer.

Materials and Methods

Patients with bladder cancer who underwent 3,0 Tesla DW-MRI of the bladder before TUR-B or radical cystectomy were eligible for this prospective IRB-approved study. Histological specimen were immunohistochemically stained for the following markers: p53, p21 and ki67. Two board-certified uropathologists reviewed the specimens blinded to DW-MRI results. Histological grade and T-stage were classified according to the WHO 2004 and the 2009 TNM classification, respectively. Nonparametric univariate and multivariate statistics including correlation, logistic regression and ROC analysis were applied.

Results

Muscle invasive bladder cancer was histologically confirmed in 10 out of 41 patients. All examined tissue biomarkers were significantly correlated with ADC values (p<0.05, respectively). Based on multivariate analysis, p53 and ADC are both independent prognostic factors for muscle invasiveness of bladder cancer (>/ = T2). (p = 0.013 and p = 0.018).

Conclusion

ADC values are associated with cell cycle and proliferative biomarkers and do thereby reflect invasive and proliferative potential in bladder cancer. ADC and p53 are both independent prognostic factors for muscle invasiveness in bladder cancer.  相似文献   
60.
This study investigated the association of hepatocyte nuclear factor 4 (HNF4) alpha single nucleotide polymorphisms (SNPs) with type 2 diabetes with or without metabolic syndrome in Malaysia. Nine HNF4 alpha SNPs were genotyped in 390 type 2 diabetic subjects with metabolic syndrome, 135 type 2 diabetic subjects without metabolic syndrome, and 160 control subjects. The SNPs rs4810424, rs1884613, and rs2144908 were associated with protection against type 2 diabetes without metabolic syndrome (recessive P = 0.018, OR 0.32; P = 0.004, OR 0.25; P = 0.005, OR 0.24, respectively). The 6-SNP haplotype2 CCCGTC containing the risk genotype of these SNPs was associated with higher risk for type 2 diabetes with or without metabolic syndrome (P = 0.002, OR 2.2; P = 0.004, OR 3.1). These data suggest that HNF4 alpha SNPs and haplotypes contributed to increased type 2 diabetes risk in the Malaysian population.  相似文献   
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