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101.
Consumption of raw oysters is an exposure route for human norovirus (NoV) and hepatitis A virus (HAV). Therefore, efficient postharvest oyster treatment technology is needed to reduce public health risks. This study evaluated the inactivation of HAV and the NoV research surrogate, murine norovirus-1 (MNV-1), in oysters (Crassostrea virginica) by electron beam (E-beam) irradiation. The reduction of potential infection risks was quantified for E-beam irradiation technology employed on raw oysters at various virus contamination levels. The E-beam dose required to reduce the MNV and HAV titer by 90% (D10 value) in whole oysters was 4.05 (standard deviations [SD], ±0.63) and 4.83 (SD, ±0.08) kGy, respectively. Microbial risk assessment suggests that if a typical serving of 12 raw oysters was contaminated with 105 PFU, a 5-kGy treatment would achieve a 12% reduction (from 4.49 out of 10 persons to 3.95 out of 10 persons) in NoV infection and a 16% reduction (from 9.21 out of 10 persons to 7.76 out of 10 persons) in HAV infections. If the serving size contained only 102 PFU of viruses, a 5-kGy treatment would achieve a 26% reduction (2.74 out of 10 persons to 2.03 out of 10 persons) of NoV and 91% reduction (2.1 out of 10 persons to 1.93 out of 100 persons) of HAV infection risks. This study shows that although E-beam processing cannot completely eliminate the risk of viral illness, infection risks can be reduced.  相似文献   
102.
Hypertension-associated end-organ damage commonly leads to cardiac and renal fibrosis. As no effective anti-fibrotic therapy currently exists, the unchecked progression of fibrogenesis manifests as cardio-renal failure and early death. We have previously shown that FATp300—p300 with intrinsic factor acetyltransferase activity—is an essential epigenetic regulator of fibrogenesis, and is elevated in several fibrotic tissues. In this report, we investigate the therapeutic efficacy of a novel FATp300 inhibitor, L002, in a murine model of hypertensive cardio-renal fibrosis. Additionally, we examine the effects of L002 on cellular pro-fibrogenic processes and provide mechanistic insights into its antifibrogenic action. Utilizing cardiac fibroblasts, podocytes, and mesangial cells, we demonstrate that L002 blunts FATp300-mediated acetylation of specific histones. Further, incubating cells with L002 suppresses several pro-fibrogenic processes including cellular proliferation, migration, myofibroblast differentiation and collagen synthesis. Importantly, systemic administration of L002 in mice reduces hypertension-associated pathological hypertrophy, cardiac fibrosis and renal fibrosis. The anti-hypertrophic and anti-fibrotic effects of L002 were independent of blood pressure regulation. Our work solidifies the role of epigenetic regulator FATp300 in fibrogenesis and establishes it as a pharmacological target for reducing pathological matrix remodeling and associated pathologies. Additionally, we discover a new therapeutic role of L002, as it ameliorates hypertension-induced cardio-renal fibrosis and antagonizes pro-fibrogenic responses in fibroblasts, podocytes and mesangial cells.  相似文献   
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Nephrotic syndrome (NS) is a kidney disease predominantly present in children with idiopathic condition; final stage of the disease progresses into end-stage renal disease. Generally, NS is treated using standard steroid therapy, however; most of the children are steroid sensitive and about 15–20% are non-responders (SRNS). Non-responsiveness of these children would be a risk with the possibility of mutational changes in podocyte genes (NPHS1, NPHS2, WT1, PLCE1). The mutation in podocyte genes is associated with SRNS. NPHS1, NPHS2, and WT1 genes are identified/directly linked to SRNS. The present study is a surveillance on the mutation analysis of WT1 (exons 8 and 9) and NPHS2 (exons 1–8) gene in SRNS followed by clinical management. In the present study, we analyzed these two genes in a total of 117 SRNS (73 boys and 44 girls) children. A total of five mutations were detected in six children. First, WT1 mutation was detected at 9th intron-IVS 9 + 4C > T position in one SRNS female patient. This WT1 mutation was identified in a girl having Frasier Syndrome (FS) with focal segmental glomerulosclerosis and a complete sex reversal found through molecular and karyological screening. In NPHS2, missense mutations of P20L (in two children), P316S, and p.R229Q, and a frame shift mutation of 42delG were detected. Thus, applying molecular investigation helped us to decide on treatment plan of SRNS patients, mainly to avoid unnecessary immunosuppressive treatment.  相似文献   
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The agonists of peroxisome proliferator-activated receptor-gamma (PPARgamma) ameliorate cardiovascular complications associated with diabetes mellitus. We tested the hypothesis that recovery from ailing to failing myocardium in diabetes by PPARgamma agonist is in part due to decreased matrix metalloproteinase-9 (MMP-9) activation and left ventricular (LV) tissue levels of homocysteine (Hcy). C57BL/6J mice were made diabetic (D) by feeding them a high-fat calorie diet. PPARgamma was activated by adding pioglitazone (Pi) to the diet. After 6 wk, mice were grouped into: normal calorie diet (N), D, N + Pi and D + Pi (n = 6 in each group). LV variables were measured by echocardiography, endothelial-myocyte (E-M) coupling was measured in cardiac rings, and MMP-9 activation was measured by zymography. Blood glucose levels were twofold higher in D mice compared with N mice. Pi decreased the levels of glucose in D mice to the levels in N mice. LV Hcy levels were 3.5 +/- 0.5 microM in N groups compared with 12.4 +/- 0.6 microM in D groups. Treatment with Pi normalized the LV levels of Hcy but had no effect on plasma levels of Hcy. In the D group, LV contraction was reduced compared with that of the N group and was ameliorated by treatment with Pi. LV wall thickness was reduced to 0.25 +/- 0.02 mm in the D group compared with 0.42 +/- 0.01 mm in the N group. LV diastolic diameter was 3.05 +/- 0.01 mm in the D group compared with 2.20 +/- 0.02 mm in the N group. LV systolic diameter was 1.19 +/- 0.02 mm in the D group and 0.59 +/- 0.01 mm in the N group. Pi normalized the LV variables in D mice. The responses to ACh and nitroprusside were attenuated in diabetic hearts, suggesting that there was E-M uncoupling in the D group compared with the N group, which was ameliorated by Pi. Plasma and LV levels of MMP-2 and -9 activities were higher in the D group than in the N group but normalized after Pi treatment. These results suggest that E-M uncoupling in the myocardium, in part, is due to increased MMP activities secondary to suppressing PPARgamma activity in high-fat, calorie-induced Type 2 diabetes mellitus.  相似文献   
108.
Obesity is emerging as a potential risk factor for male infertility. It is a multifactorial disorder with primarily genetic and/or environmental factors. Our earlier studies have shown differential effects of genetically inherited-and high fat diet induced-obesity on hormones, fertility and spermatogenesis in adult male rats. In the present study, we assessed the effect of high fat diet induced – and genetically inherited – obesity on the underlying molecular mechanisms affecting spermatogenesis. The expression of hormone receptors, cytokines and markers of oxidative stress as well as cell cycle mediators were affected in both the obese groups, however, the changes were different in the two groups. This could be due to difference in fat distribution between the two types of obese groups. Altered expression of hormone receptors, cytokines, cell cycle mediators and differential effects on oxidative stress could be the plausible reason for differential changes in germ cell population in both the groups.  相似文献   
109.
When the complexes [Cu(L1)(H2O)](ClO4)21, where L1 = 4-methyl-1-(pyrid-2-ylmethyl)-1,4-diazacycloheptane, and [Cu(L2)Cl2] 2, where L2 = 4-methyl-1-(quinol-2-ylmethyl)-1,4-diazacycloheptane are interacted with one/two equivalents of bis(p-nitrophenylphosphate, (p-NO2Ph)2PO2, BNP), no hydrolysis of BNP is observed. From the solution the adducts of copper(II) complexes [Cu2(L1)2((p-NO2Ph)2PO2)2]-(ClO4)23 and [Cu(L2)((p-NO2Ph)2PO2)2]·H2O 4 have been isolated and structurally characterised. The X-ray crystal structure of 3 contains two Cu(L1) units bridged by two BNP molecules. The Cu···Cu distance (5.1 Å) reveals no Cu-Cu interaction. On the other hand, the complex 4 is mononuclear with Cu(II) coordinated to the 3N ligand as well as BNP molecules through phosphate oxygen. The trigonality index (τ, 0.37) observed for 4 is high suggesting the presence of significant trigonal distortion in the coordination geometry around copper(II). The complexes are further characterized by spectral and electrochemical studies.  相似文献   
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