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111.
以N,N,N′,N′-四缩水甘油基-4,4′-二氨基二苯甲烷(TGDDM)和丙烯酸(AA)为原料,合成了一种既含有环氧基又含有乙烯基酯基团的新型混杂多官能团齐聚物树脂(MEVO)。以过氧化甲乙酮(MEKP)为引发剂、甲基四氢苯酐(MeTHPA)为环氧固化剂与MEVO共混制备了MEVO-MEKP、MEVO-MeTHPA和MEVO-MEKP-MeTHPA 3种固化体系。通过非等温DSC和FT-IR研究了MEVO的固化反应,求得了各体系表观反应活化能。结果表明:在MEVO-MEKP固化体系中,乙烯基酯按照自由基聚合机理固化,对环氧基没有影响;在MEVO-MeTHPA固化体系中,环氧基固化过程中乙烯基酯会发生热固化;在MEVO-MEKP-MeTHPA固化体系中,乙烯基酯和环氧基按各自机理固化并互相影响。  相似文献   
112.
Gastrodin has been showed to possess many beneficial physiological functions, including protection against inflammation and oxidation and apoptosis. Studies showed inflammation and oxidation play important roles in producing liver damage and initiating hepatic fibrogenesis. However, it has not been reported whether gastrodin has a protective effect against hepatic fibrosis or not. This is first ever made attempts to test gastrodin against liver fibrosis in bile duct ligation (BDL) rats. The aim of the present study is to evaluate the effect of gastrodin on BDL-induced hepatic fibrosis in rats. BDL rats were divided into two groups, BDL alone group, and BDL-gastrodin group treated with gastrodin (5 mg/ml in drinking water). The effects of gastrodin on BDL-induced hepatic injury and fibrosis in rats were estimated by assessing serum, urine, bile and liver tissue biochemistry followed by liver histopathology (using hematoxylin & eosin and sirius red stain) and hydroxyproline content measurement. The results showed that gastrodin treatment significantly reduced collagen content, bile duct proliferation and parenchymal necrosis after BDL. The serum alanine aminotransferase (ALT) and serum aspartate aminotransferase (AST) decreased with gastrodin treatment by 15.1 and 23.6 percent respectively in comparison to BDL group did not receive gastrodin. Gastrodin also significantly increased the level of serum high density lipoprotein (HDL) by 62.5 percent and down-regulated the elevated urine total bilirubin (TBIL) by 56.5 percent, but had no effect on total bile acid (TBA) in serum, bile and liver tissues. The immunohistochemical assay showed gastrodin remarkably reduced the expressions of CD68 and NF-κB in BDL rats. Hepatic SOD levels, depressed by BDL, were also increased by gastrodin by 8.4 percent. In addition, the increases of hepatic MDA and NO levels in BDL rats were attenuated by gastrodin by 31.3 and 38.7 percent separately. Our results indicate that gastrodin significantly attenuated the severity of BDL-induced hepatic injury and fibrosis by attenuating oxidative stress and inflammation. Taken together, these findings suggest that gastrodin might be an effective antifibrotic drug in cholestatic liver disease.  相似文献   
113.
Ruellia tuberosa L. (RTL) has been used as a folk medicine for curing diabetes mellitus in East Asia decades. This study investigated the effect of RTL on hepatic detoxification enzyme expression in diabetic rats. Male Wistar rats were fed a high fat diet (HFD) and intraperitoneally injected with streptozotocin (STZ) to induce diabetes. Subsequently, rats received oral administrations of 100 or 400 mg kg−1 body weight RTL extract, in either water (RTLW) or ethanol (RTLE), once a day for 4 weeks. The real-time PCR analyses showed that abnormality of hepatic phase I and II detoxification enzyme expression was observed in diabetic rats. However, both RTLW and RTLE significantly normalized the expression of hepatic phase I detoxification enzymes such as CYP 2E1, and expression of phase II detoxification enzymes such as UGT 1A7 and GST M1 in diabetic rats. Furthermore, we found that fasting serum glucose, hemoglobin A1C (HbA1C) and the area under the curve of oral glucose tolerance test (AUCOGTT) levels were significantly reduced in both RTLW and RTLE treated diabetic rats. Moreover, both RTLW and RTLE significantly increased the activity of hepatic anti-oxidative enzymes such as superoxide dismutase (SOD) in diabetic rats. The present study suggests that RTL may ameliorate abnormal hepatic detoxification function via alleviating hyperglycemia and enhancing hepatic antioxidant capacity in HFD/STZ-induced diabetic rats.

Ruellia tuberosa L. (RTL) has been used as a folk medicine for curing diabetes mellitus in East Asia decades.  相似文献   
114.
In this study, a series of ethylene glycol modified urea–melamine–formaldehyde resins (EUMFs) were synthesized from urea, melamine, paraformaldehyde and ethylene glycol, and then incorporated into rigid polyurethane foams (RPUFs) as a reactive-type liquid flame retardant. The structure of EUMFs was characterized by Fourier transform infrared spectrometry; the morphology of the foams was characterized by scanning electron microscopy; and the thermal degradation and fire behavior of RPUFs were characterized by limiting oxygen index (LOI), cone calorimetry test and thermogravimetry analysis. The results show that the incorporation of EUMFs results in an increase in thermal stability, smoke suppression and LOI of RPUFs. As the melamine loading in EUMFs increases, the peak heat release rate and the total heat release of RPUFs decrease significantly, but the LOI increases slightly. Compared with the original foam, the cells of RPUFs become less regular with nonuniform diameters. In general, EUMFs show excellent flame retardancy and smoke suppression for RPUFs.

In this study, a series of ethylene glycol modified urea–melamine–formaldehyde resins were synthesized, and then incorporated into rigid polyurethane foams as a reactive-type liquid flame retardant.  相似文献   
115.
Bioactive and degradable scaffolds of nano magnesium silicate (n-MS)/zein (ZN)/poly(caprolactone) (PCL) ternary composites were prepared by 3D-printing method. The results showed that the 3D-printed scaffolds possessed controllable pore structure, and pore morphology, pore size, porosity and pore interconnectivity of the scaffolds can be efficiently adjusted. In addition, the apatite-mineralization ability of the scaffolds in simulated body fluids was obviously improved with the increase of ZN content, in which the scaffold with 20 w% ZN (C20) possessed excellent apatite-mineralization ability. Moreover, the degradability of the scaffolds was significantly enhanced with the increase of ZN content in the scaffolds. The degradation of ZN produced acidic products that could neutralize the alkaline products from the degradation of n-MS, which avoid the increase of pH value in degradable solution. Furthermore, the MC3T3-E1 cells responses (e.g. proliferation and differentiation, etc.) to the scaffolds were significantly promoted with the increase of ZN content. The in vivo osteogenesis of the scaffolds implanted the femur defects of rabbits was investigated by micro-CT and histological analysis. The results demonstrated that the new bone formation was significantly enhanced with the increase of ZN content, in which the C20 scaffold induced the highest new bone tissues, indicating excellent osteogenesis. The results suggested that the ZN in the ternary composite scaffolds played key roles in assisting bone regeneration in vivo.

Zein regulating apatite mineralization, degradability, cells responses and osteogenesis of 3D-printed scaffold of n-MS/ZN/PCL ternary composite.  相似文献   
116.
The present work reports a direct role of mitochondrial oxidative stress induced aberrant chromatin regulation, as a central phenomenon, to perturbed genomic integrity in the testicular milieu. Oxygen-radical injury following N-succinimidyl N-methylcarbamate treatment in mouse spermatogonial epithelial (GC-1 spg) cells induced functional derailment of mitochondrial machinery. Mitophagy resulted in marked inhibition of mitochondrial respiration and reduced mtDNA copy number. Impaired cell cycle progression along with altered H3K9me1, H4K20me3, H3, AcH3 and uH2A histone modifications were observed in the treated cells. Dense heterochromatin foci and aberrant expression of HP1α in nuclei of treated cells implied onset of senescence associated secretory phenotype mediated through nuclear accumulation of NF-κB. Neoplastic nature of daughter clones, emerged from senescent mother phenotypes was confirmed by cytogenetic instability, aberrant let-7a and let-7b miRNA expression and anchorage independent growth. Together, our results provide the first insights of redox-dependent epigenomic imbalance in spermatogonia, a previously unknown molecular paradigm.  相似文献   
117.
Periodontitis has been defined as the Sixth complication of Diabetes Mellitus. Since both diabetes mellitus and periodontitis have a high prevalence in the general population, the Italian Society of Diabetology, the Italian Society of Periodontology and Implantology and the Italian Association of Clinical Diabetologists revised the present scientific literature in the present consensus report.A bi-directional interaction was demonstrated: Patients affected by type 1 and type 2 diabetes have a higher prevalence of periodontitis than the general population, due to several metabolic factors (e.g. chronic hyperglycemia, autoimmunity, dietary and life-style factors); similarly, periodontitis predisposes to type 2 diabetes mellitus mainly via the increase of systemic cytokines release. Conversely, improvement of metabolic control of diabetic patients delay the progression of periodontitis as well as periodontitis treatment reduces glycosylated hemoglobin levels in blood.Due to the bi-directional causal interaction between periodontitis and diabetes mellitus, a strict collaboration among dentists and diabetologists is required and strongly recommended. The inter-societies consensus proposes specific flow-diagrams to improve the treatment of patients and management of the general population regarding the issue of periodontitis and diabetes.  相似文献   
118.
《Diabetes & metabolism》2022,48(6):101365
AimsTriglyceride–glucose (TyG) index has been proposed as a simple surrogate marker of insulin resistance. However, few studies have investigated the association of TyG index with heart failure (HF). We aimed to explore the relationship between TyG index and incident HF.MethodsA total of 138,620 participants from the Kailuan study were included for analysis. TyG index was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL) / 2]. Cox proportional hazard models were used to investigate the association between TyG index and the risk of HF. Restricted cubic spline analysis was applied to evaluate the dose-response relationship between TyG index and the risk of HF.ResultsThere were 1602 incident HF cases among the 138,620 participants during a median follow-up of 8.78 years. Compared with those in the lowest quartile group of TyG index, participants with the highest quartile of TyG index had a 24% higher risk of HF (HR=1.24, 95%CI=1.07-1.44) after adjusting for other risk factors. Restricted cubic spline analysis showed a significant J-shaped dose-response relationship between TyG index and risk of HF (P for non-linearity < 0.001). The significant association was still observed among the men and participants with or without abdominal obesity in subgroup analyses.ConclusionThe TyG index was positively associated with the risk of HF, which indicates that the TyG index might be useful to identify people at high-risk for developing HF.  相似文献   
119.
Sequence polymorphisms of Y chromosome short tandem repeat (Y-STR) markers can be unveiled using next generation sequencing (NGS). Compared to capillary electrophoresis, NGS has the advantage of distinguishing between some alleles of the same length. Here, a 68-plex in-house panel covering 67 Y-STR loci and the sex determinant Amelogenin locus, was developed. The accuracy of this panel was 100% concordant with three standard reference samples. The sensitive was as low as 250 pg. A total of 466 length-based alleles, 806 sequence-based alleles, and 149 haplotypes were observed across 149 Chinese Han individuals. The total haplotype diversity and discrimination capacity was 1.0000 in detected samples. The DYS710 locus possessed the highest diversity by sequence among these Y-STRs, with 109 sequence-based alleles observed. Micro-variant alleles with the same length were observed in 39 Y-STR loci, with their sequence variations mainly attributable to repeat pattern variations. While the number of sequence-based alleles identified for DYS447, DYS449, DYS710, DYS720 and DYF387S1a/b was approximately three times that of their length-based alleles, flanking sequence variations were observed in 18 alleles. In addition, 201 sequence-based alleles in 42 loci were newly discovered. This significantly expanded the knowledge of human Y-STR sequence polymorphisms. Collectively, the 68-plex panel provided reliable Y-STR results as well as higher resolution for paternal lineage analysis.  相似文献   
120.
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