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101.
Fuzhuan brick-tea extract (FBTE) affects the physiology of mice infected with Escherichia coli O157:H7. For 10 consecutive days, 0.05, 0.5, and 1.0 g/mL FBTE was administered intragastrically to three groups of infected Kunming mice, and changes in immunological function, hematology, and histopathology were examined. The results revealed upregulation of platelets, total protein, and albumin along with downregulation of serum triglycerides, aspartate aminotransferase, creatinine, and urea nitrogen in FBTE-treated mice. Histological sections of stomach, kidney, duodenum, ileum, and colon suggested that infected mucous membranes could be rehabilitated by low- and high-dose FBTE and that inflammation was alleviated. Similarly, increased thymic function in mice treated with middle- and high-dose FBTE led to elevated serum hemolysin antibody titer and increased CD4+ and CD8+ T cells, as indicated by CD4+ and CD8+ expression on intestinal mucosa. Monocyte and macrophage function was improved by three FBTE dosages tested. Colonic microbiota analysis by denaturing gradient gel electrophoresis (DGGE) revealed characteristic bands in infected mice treated with middle- and high-dose FBTE and increased species diversity in Lactobacillus, Bacteroides, and Clostridium cluster IV. These results suggest that FBTE may protect kidney and liver of mice infected with E. coli O157:H7, improve immune function, and regulate the colonic microbiota. 相似文献
102.
Yin Xiangbao Wu LinquanHuang Mingwen Zhou FanWang Kai Yu XinWang Kaiyang Fu Huaqun 《Biomedicine & Pharmacotherapy》2014
Low sensitivity of tumor tissue, targeting and sustained release of the drug are bottlenecks of the effect of chemotherapy on hepatocellular carcinoma. In this study, we used the ribosome display technology to screen human anti-VEGFR 2-single-chain antibody (ScFv) that could target directly to VEGFR2, and nanotechnology to prepare As2O3-nanoparticles. Then we built anti-VEGFR-2ScFv-As2O3-stealth nanoparticles using molecular coupling technology, which significantly increased anti-tumor effect while reducing toxicity. The in vivo tissue targeting distribution and anti-tumor effects of the anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles were investigated. Our results showed that anti-VEGFR-2 ScFv-As2O3-stealth nanoparticles could inhibit the development of liver cancer xenograft as a targeting agent and also significantly inhibit angiogenesis. 相似文献
103.
《Journal of pharmaceutical sciences》2019,108(7):2207-2237
This review describes the landscape of novel modalities such as cell and gene therapies, viruses, other novel biologics, oligomers, and emerging technologies, including modern analytics. We summarize the regulatory history and recent landmark developments in some major markets and examine specific chemistry, manufacturing, and controls (CMC) challenges, including suggestions for exploration of potential science-based approaches in support of regulatory strategy development from an industry perspective. In addition, we evaluate the economic factors contributing to patient access to innovation and discuss the impact of regulation. There is a desperate need for a consistent form of regulation where global approaches to regulatory strategies can be harmonized, and specific CMC challenges can be dealt with using the appropriate science and risk-based tools. Although these tools are well described in current guidance documents, the specifics of applicability to complex novel modalities can still result in differing regulatory advice and outcomes. The future goals for efficiently regulating innovative modalities and technologies could be aided by more regulatory harmonization, regulatory education, and industry cooperation through consortia, enabling industry to supply key information to regulators in a transparent yet well-defined manner, and utilizing mutually understood risk-benefit analyses to produce drugs with appropriate safety, efficacy, and quality characteristics. 相似文献
104.
105.
Chloroplast overexpression of rice caffeic acid O‐methyltransferase increases melatonin production in chloroplasts via the 5‐methoxytryptamine pathway in transgenic rice plants 下载免费PDF全文
Recent analyses of the enzymatic features of various melatonin biosynthetic genes from bacteria, animals, and plants have led to the hypothesis that melatonin could be synthesized via the 5‐methoxytryptamine (5‐MT) pathway. 5‐MT is known to be synthesized in vitro from serotonin by the enzymatic action of O‐methyltransferases, including N‐acetylserotonin methyltransferase (ASMT) and caffeic acid O‐methyltransferase (COMT), leading to melatonin synthesis by the subsequent enzymatic reaction with serotonin N‐acetyltransferase (SNAT). Here, we show that 5‐MT was produced and served as a precursor for melatonin synthesis in plants. When rice seedlings were challenged with senescence treatment, 5‐MT levels and melatonin production were increased in transgenic rice seedlings overexpressing the rice COMT in chloroplasts, while no such increases were observed in wild‐type or transgenic seedlings overexpressing the rice COMT in the cytosol, suggesting a 5‐MT transport limitation from the cytosol to chloroplasts. In contrast, cadmium treatment led to results different from those in senescence. The enhanced melatonin production was not observed in the chloroplast COMT lines relative over the cytosol COMT lines although 5‐MT levels were equally induced in all genotypes upon cadmium treatment. The transgenic seedlings with enhanced melatonin in their chloroplasts exhibited improved seedling growth vs the wild type under continuous light conditions. This is the first report describing enhanced melatonin production in chloroplasts via the 5‐MT pathway with the ectopic overexpression of COMT in chloroplasts in plants. 相似文献
106.
Michelle L. Colgrave Andrew C. Kotze James S. McCarthy David J. Craik 《Acta tropica》2009,109(2):163-166
Hookworm infection is a leading cause of maternal and child morbidity in countries of the tropics and subtropics, as well as being an important parasite in companion-animal medicine. The cyclotides are a novel family of cyclic cystine knot containing peptides from plants that have been shown to possess anthelmintic activity against Haemonchus contortus and Trichostrongylus colubriformis, two important gastrointestinal nematodes of sheep. In the current study we demonstrated the in vitro effects of three representative cyclotides, kalata B1, kalata B6 and cycloviolacin O14, on the viability of larval and adult life stages of the dog hookworm Ancylostoma caninum, and larvae of the human hookworm Necator americanus. The cyclotides showed significant anthelmintic activity towards both hookworm species. The different cyclotides showed similar patterns of relative activity as that seen previously with the livestock nematode species. This study demonstrates that cyclotides have promising activity in vitro against important parasites of companion animals and humans. 相似文献
107.
S.H. Schneider P.M. Komanicky M.N. Goodman N.B. Ruderman 《Metabolism: clinical and experimental》1981,30(6):590-595
The effect of dichloroacetate (DCA), an activator of pyruvate dehydrogenase, on the performance of fed, untrained rats was evaluated while swimming for different durations. DCA-treated rats were able to swim almost 40% longer than controls (354 ± 18 versus 255 ± 18 sec, p < .001). This was associated with lower levels of blood and muscle lactate at rest and after 210 and 240 sec of swimming. At exhaustion, blood lactate was the same in the two groups even though the DCA rats had worked for an additional 99 sec (16.9 ± 1.2 versus 15.8 ± 1.2 mM/L NS). Pretreatment with DCA did not alter the usual exercise-induced decreases in muscle ATP and creatine phosphate or liver glycogen. After 210 sec of exercise, plasma FFA and blood glucose and acetoacetate were also the same in the two groups; however, β-hydroxybutyrate was somewhat higher, and there was a small but significant sparing of muscle glycogen in the DCA group. The data indicate that DCA enhances the ability of rats to exercise at near maximal work loads. They are consistent with the notion that improved endurance is a consequence of a decreased rate of lactate accumulation; however, the possibility that it is secondary to some other action of DCA cannot be excluded. 相似文献
108.
R C Dhingra F Amat-Y-Leon C Wyndham P Denes D Wu J M Pouget K M Rosen 《The American journal of cardiology》1976,38(4):429-434
Electrophysiologic studies were conducted in 17 patients without apparent sinus node disease before and after intravenous administration of 1 to 2 mg of atropine. Mean values in milliseconds (+/- standard error of the mean) before and after administration of atropine were as follows: sinus cycle length 846 +/- 26.4 versus 647 +/- 20.0 (P less than 0.001); sinus nodal recovery time 1,029 +/- 37 versus 774 +/- 36 (P less than 0.001); mean calculated sinoatrial (S-A) conduction time 103 +/- 5.7 versus 58 +/- 3.9 (P less than 0.001); mean P-A interval 34 +/- 1.5 msec versus 31 +/- 1.5 (P less than 0.05); mean atrial effective and functional refractory periods during sinus rhythm 285 +/- 11.3 versus 238 +/- 7.9 and 331 +/0 11.6 versus 280 +/- 8.6, respectively (P less than 0.001 for both); mean atrial effective and functional refractory periods measured at equivalent driven cycle length 239 +/- 7.7 versus 213 +/- 7.4 and 277 +/- 11.4 versus 245 +/- 9.5, respectively (P less than 0.001 for both). In conclusion, atropine shortened sinus cycle length, sinus nodal recovery time and calculated S-A conduction time. The shortening of atrial refractory periods with atropine implies that vagotonia prolongs atrial refractoriness in man. 相似文献
109.
110.
Talha M. Qureshi Anam Khan Huma Javaid Abdalaziz Tabash Mohammed S. Hussein Mohamed O. Othman 《The American journal of the medical sciences》2021,361(5):616-623
BackgroundHypertriglyceridemia induced acute pancreatitis (HIAP) is the third common cause of acute pancreatitis. HIAP can result in recurrent attacks of severe AP with significant morbidity and mortality. Hypertriglyceridemia (HTG) could be primary or secondary. Although genetic causes of HTG are well studied, the prevalence of secondary causes of HTG in patients presenting with HIAP is not well characterized. This study aimed to identify the prevalence of risk factors for secondary hypertriglyceridemia among patients presenting with HIAP in a tertiary referral center in a large metropolitan area.MethodsThis is a retrospective analysis of all patients admitted with AP from August 2012–2017. A subgroup of patients with triglycerides >880 mg/dl were included for analysis. Secondary causes of HTG were identified. Secondary analysis evaluating the severity of pancreatitis was performed.ResultsThere were 3,746 patients admitted for AP of which 57 patients had AP and HTG. Of these 57 patients, 70.2% had history of diabetes mellitus, 26.3% had history of heavy alcohol use, 22.8% had chronic kidney disease, 47.3% with obesity, and 21.1% with metabolic syndrome. Two patients were classified as unexplained HTG. Secondary analysis showed a total of 45.6% of patients requiring ICU admission. 26.3% of patients with severe inflammatory pancreatitis and 17.5% of patients with severe necrotizing pancreatitis.ConclusionsIn our cohort of HIAP, 55 out of 57 patients had secondary causes for HTG. Identifying secondary causes of HTG during acute hospitalization is important to tailor outpatient treatment in order to prevent future admissions with HIAP. 相似文献