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11.
Quercetin (QCT) and isorhamnetin (ISO), natural flavonoids, were both shown to possess antifibrotic activity in in vivo and in vitro models of hepatic fibrosis. Although ISO is a direct metabolite of QCT differing by a methyl group, it has been reported to be absorbed more adequately and eliminated slower than QCT after oral administration. Our aim of the study was to investigate biological effect of mono-methylated QCT derivatives against fibrosis using rat hepatic stellate cells (HSC-T6). All test derivatives were synthesized from QCT. HSC-T6 cells were induced by TGFβ and treated with derivatives followed by cell proliferation assay, immunofluorescence staining of αSMA, and gene expression analysis of fibrosis markers. All compounds showed a dose- and time-dependent antiproliferation effect. ISO, 3-O-methylquercetin (3MQ), and rhamnetin (RHA) reduced αSMA mRNA; 3MQ prevented the augmentation of collagen I mRNA; and compounds, except azaleatin and 3MQ, reduced Timp1 mRNA expression in TGFβ-induced HSCs. In conclusion, each compound had singular effect against different features of fibrosis depending on the position of methyl group although the further mechanism of action of compounds during fibrosis development remains to be investigated. These findings suggest that antifibrotic effect of quercetin can be enhanced by adding methyl group on functionally important position.  相似文献   
12.
Qin  Xingping  Akter  Farhana  Qin  Lingxia  Xie  Qiurong  Liao  Xinyu  Liu  Rui  Wu  Xueting  Cheng  Nina  Shao  Lingmin  Xiong  Xiaoxing  Liu  Renzhong  Wan  Qi  Wu  Songlin 《Neurochemical research》2019,44(11):2658-2669
Neurochemical Research - Subarachnoid hemorrhage (SAH) is a form of stroke associated with high mortality and morbidity. Despite advances in treatment for SAH, the prognosis remains poor. We have...  相似文献   
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The specific identification of Lymnaeid snails is based on a comparison of morphological characters of the shell, radula, renal and reproductive organs. However, the identification is complicated by dissection process, intra and interspecific similarity and variability of morphological characters. In the present study, polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) techniques targeted to the first and second internal transcribed spacers (ITS1 and ITS2) rDNA and to the mitochondrial 16S ribosomal gene (16S rDNAmt) were used to differentiate the species Lymnaea columella, L. viatrix, and L. diaphana from some localities of Brazil, Argentina, and Uruguay as well as to verify whether the molecular results corroborates the classical morphological method.PCR-RFLP analysis of the ITS1, ITS2, and 16S using 12 restriction enzymes revealed characteristic patterns for L. columella and L. diaphana which were concordant with the classical morphology. On the other hand, for L. viatrix populations a number of 1 to 6 profiles were generated while morphology provided the species pattern results.  相似文献   
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2',3'-Dihydrophylloquinone (dihydro-K1) is a hydrogenated form of vitamin K1 (K1), which is produced during the hydrogenation of K1-rich plant oils. In this study, we found that dihydro-K1 counteracts the sodium warfarin-induced prolonged blood coagulation in rats. This indicates that dihydro-K1 functions as a cofactor in the posttranslational gamma-carboxylation of the vitamin K-dependent coagulation factors. It was also found that dihydro-K1 as well as K1 inhibits the decreasing effects of warfarin on the serum total osteocalcin level. In rats, dihydro-K1 is well absorbed and detected in the tissues of the brain, pancreas, kidney, testis, abdominal aorta, liver and femur. K1 is converted to menaquinone-4 (MK-4) in all the above-mentioned tissues, but dihydro-K1 is not. The unique characteristic of dihydro-K1 possessing vitamin K activity and not being converted to MK-4 would be useful in revealing the as yet undetermined physiological function of the conversion of K1 to MK-4.  相似文献   
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Insulin-resistant states are characterized by hypertriglyceridemia, predominantly because of overproduction of hepatic very low density lipoprotein particles. The additional contribution of intestinal lipoprotein overproduction to the dyslipidemia of insulin-resistant states has not been previously appreciated. Here, we have investigated intestinal lipoprotein production in a fructose-fed hamster model of insulin resistance previously documented to have whole body and hepatic insulin resistance, and hepatic very low density lipoprotein overproduction. Chronic fructose feeding for 3 weeks induced significant oversecretion of apolipoprotein B48 (apoB48)-containing lipoproteins in the fasting state and during steady state fat feeding, based on (a) in vivo Triton WR1339 studies of apoB48 production as well as (b) ex vivo pulse-chase labeling of intestinal enterocytes from fasted and fed hamsters. ApoB48 particle overproduction was accompanied by increased intracellular apoB48 stability, enhanced lipid synthesis, higher abundance of microsomal triglyceride transfer protein mass, and a significant shift toward the secretion of larger chylomicron-like particles. ApoB48 particle overproduction was not observed with short-term fructose feeding or in vitro incubation of enterocytes with fructose. Secretion of intestinal apoB48 and triglyceride was closely linked to intestinal enterocyte de novo lipogenesis, which was up-regulated in fructose-fed hamsters. Inhibition of fatty acid synthesis by cerulenin, a fatty acid synthase inhibitor, resulted in a dose-dependent decrease in intestinal apoB48 secretion. Overall, these findings further suggest that intestinal overproduction of apoB48 lipoproteins should also be considered as a major contributor to the fasting and postprandial dyslipidemia observed in response to chronic fructose feeding and development of an insulin-resistant state.  相似文献   
18.
C-reactive protein (CRP) is a sensitive marker of inflammation induced by both IL-6 and IL-1. Thus, genetic variation in these genes could be associated with the variety in C-reactive protein levels, and therefore with the severity of the entire inflammatory response. Even a subtle elevation in baseline CRP levels in healthy individuals has been found to significantly increase the risk for cardiovascular diseases. Therefore, to find out the possible role of pro-inflammatory cytokines in CRP baseline regulation we conducted a study of 338 healthy blood donors whose CRP levels were determined and whose single nucleotide polymorphisms of IL1A(C/T)-889, IL1B(C/T)-511, IL1B(C/T) + 3954, IL6(G/C)-174 and ILRN (a VNTR) both genotyped and haplotyped. The data revealed an association between CRP levels and the IL1B + 3954 genotype. Also, the bilocus haplotype IL1B-511*1/IL1B + 3954*2 was more frequent in subjects with below median CRP levels (< 0.72 mg/l), and composite genotype analysis of IL1B-511/IL1B + 3954 supported this finding. Our findings suggest that in healthy people, basal CRP levels are regulated by IL1B but not by IL6 genetics.  相似文献   
19.
The maximum productivity of -glucosidase by Saccharomyces cerevisiaerecombinants under the control of GALI promoter was 100 IU l–1 h–1. The highest productivity of -glucosidase by a S. cerevisiae recombinant was 16-fold more than that supported by Cellulomonas biazotea. The recombinants also co-produced ethanol from cellobiose: maximum product yield and productivity were 0.5 and 1.1 g ethanol g–1 cellobiose and g ethanol l–1 h–1, respectively.  相似文献   
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MethodologyExploratory assessments were carried out in Indonesia, Nigeria and Pakistan, reaching a range of facility types in two selected areas of each country. Record reviews and interviews of healthcare providers were carried out to assess numbers of unreported paediatric TB cases, diagnostic pathways followed and treatment regimens prescribed.

Main Findings

A total of 985 unreported diagnosed paediatric TB cases were identified over a three month period in 2013 in Indonesia from 64 facilities, 463 in Pakistan from 35 facilities and 24 in Nigeria from 20 facilities. These represent an absolute additional annualised yield to 2013 notifications reported to WHO of 15% for Indonesia, 2% for Nigeria and 7% for Pakistan. Only 12% of all facilities provided age and sex-disaggregated data. Findings highlight the challenges of confirming childhood TB. Diagnosis patterns in Nigeria highlight a very low suspicion for childhood TB. Providers note the need for paediatric medicines aligned to WHO recommendations.

Conclusion: How Market Data Can Support Better Public Health Interventions

This study emphasises the impact of incomplete reporting on the estimation of disease burden and potential market size of paediatric TB medicines. Further studies on “hubs” (facilities treating large numbers of childhood TB cases) will improve our understanding of the epidemic, support introduction efforts for new treatments and better measure markets for new paediatric medicines.  相似文献   
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