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1.
Electroacupuncture has been widely used to treat cognitive impairment after cerebral ischemia, but the underlying mechanism has not yet been fully elucidated. Studies have shown that autophagy plays an important role in the formation and development of cognitive impairment, and the phosphoinositide 3-kinase(PI3 K)/Akt signaling pathway plays an important role in autophagy regulation. To investigate the role played by the PI3 K/Akt signaling pathway in the electroacupuncture treatment of cerebral ischemia/reperfusion rat models, we first established a rat model of cerebral ischemia/reperfusion through the occlusion of the middle cerebral artery using the suture method. Starting at 2 hours after modeling, electroacupuncture was delivered at the Shenting(GV24) and Baihui(GV20) acupoints, with a dilatational wave(1–20 Hz frequency, 2 mA intensity, 6 V peak voltage), for 30 minutes/day over 8 consecutive days. Our results showed that electroacupuncture reduced the infarct volume in a rat model of cerebral ischemia/reperfusion injury, increased the mRNA expression levels of the PI3 K/Akt signaling pathwayrelated factors Beclin-1, mammalian target of rapamycin(mTOR), and PI3 K, increased the protein expression levels of phosphorylated Akt, Beclin-1, PI3 K, and mTOR in the ischemic cerebral cortex, and simultaneously reduced p53 mRNA and protein expression levels. In the Morris water maze test, the latency to find the hidden platform was significantly shortened among rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. In the spatial probe test, the number of times that a rat crossed the target quadrant was increased in rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. Electroacupuncture stimulation applied to the Shenting(GV24) and Baihui(GV20) acupoints activated the PI3 K/Akt signaling pathway and improved rat learning and memory impairment. This study was approved by the Animal Ethics Committee of the First Affiliated Hospital of Henan University of Traditional Chinese Medicine, China(approval No. 8150150901) on March 10, 2016.  相似文献   
2.
目的总结分析胃癌D2根治术后发生大出血的原因及治疗方法并探讨其对生存预后的影响。方法回顾性分析广东省中医院2012年1月至2016年3月258例行胃癌D2根治术患者的临床资料,根据术后是否发生大出血分为出血组和非出血组。结果14例患者(5.4%)术后发生大出血;吻合口出血、十二指肠残端瘘或破裂是出血的主要原因;二次手术和胃镜止血是主要治疗措施。两组的短期总生存期有统计学意义(1年:P=0.017,3年:P=0.011)。结论吻合口出血、十二指肠残端瘘或破裂是胃癌D2根治术后出血的主要原因,及时诊断和治疗能有效降低病死率。胃癌D2根治术后大出血会降低患者的短期总生存期。  相似文献   
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The objective of this study was to explore the association of sperm mitochondrial ND2 (MT-ND2) gene variants with total fertilization failure (TFF). A retrospective comparative study of 246 cases of fresh in vitro fertilization (IVF) cycles or half-intracytoplasmic sperm injection cycles in the Han Chinese population was performed from July 2011 to May 2017. A total of 59 cases undergoing TFF, and 187 control cases with normal fertilization (fertilization rates >50%) were included. The sperm mitochondrial genovariation was determined using nested sequencing. A total of 32 homoplasmic variants and 47 heteroplasmic variants of MT-ND2 gene were observed in this study. There were no significant differences in the frequencies of the 32 homoplasmic variants of MT-ND2 gene between the TFF and control groups. A total of 53 pair-wise comparisons were performed, and the general characteristics of the IVF failure and control subjects were adjusted in logistic models. Data suggested that there were no significant differences in the frequencies of point 4914, 5320, and 5426 heteroplasmic variants of MT-ND2 gene between the TFF and control groups. In addition, no significant difference was observed in the frequency of mtDNA haplogroup D or haplogroup G between the IVF failure group and the normal fertilization group. This study suggests that the MT-ND2 gene variants might not be associated with TFF.

Abbreviations: ATP: adenosine triphosphate; dNTP: deoxy-ribonucleoside triphosphate; FADH2: flavin adenine dinucleotide; FDR: false discovery rate; FSH: follicle-stimulating hormone; IVF: in vitro fertilization; LH: luteinizing hormone; MTATP6: mitochondrially encoded ATP synthase 6; MTCYB: mitochondrially encoded cytochrome b; mtDNA: mitochondrial DNA; MT-ND2: mitochondrial ND2; NADH: nicotinamide adenine dinucleotide; ND2: NADH dehydrogenase subunit 2; OXPHOS: oxidative phosphorylation; PCR: single nucleotide polymorphisms; SNPs: single nucleotide polymorphisms; TFF: total fertilization failure  相似文献   

6.
An accurate dosage determination is required in neonates when antibiotics are used. The adult data cannot be simply extrapolated to the pediatric population due to significant individual differences. We aimed to identify factors impacting ceftazidime exposure in neonates and to provide drug dosing guidance to clinicians. Forty-three neonates aged less than 60 days with proven or suspected infections were enrolled in this study. After intravenous administration, blood samples were collected, and plasma ceftazidime concentration was determined using a HPLC method. Pharmacokinetic data were fitted using a nonlinear mixed-effects model approach. One-compartmental model could nicely characterize the ceftazidime in vivo behavior. The covariate test found that the postmenstrual age (day) was strongly associated with systemic drug clearance (L/h), and the effect of body weight (kg) was identified as the covariate on distribution volume (L). Compared with the base model, the addition of covariates improved the goodness-of-fit of the final model. Model validation (bootstrap, visual predictive check, and prediction-corrected visual predictive check) suggested a robust and reliable pharmacokinetic model was developed. Personalized dosage regimens were provided based on model simulations. The intravenous dose should be adjusted according to postmenstrual age, body weight, and minimum inhibitory concentration.  相似文献   
7.
The objectives of this study were to explore sodium dodecyl sulfate (SDS) and Soluplus on the crystallization inhibition and dissolution of felodipine (FLDP) extrudates by bottom-up and top-down approaches. FLDP extrudates with Soluplus and SDS were prepared by hot melt extrusion, and characterized by polarized light microscopy, differential scanning calorimetry, and fourier transform infrared spectroscopy. Results indicated that Soluplus inhibited FLDP crystallization, and the whole amorphous solid dispersions (ASDs) were binary FLDP-Soluplus (1:3) and ternary FLDP-Soluplus-SDS (1:2:0.15~0.3 and 1:3:0.2~0.4) extrudates. Internal SDS (5%-10%) decreased glass transition temperatures of FLDP-Soluplus-SDS ternary ASDs without presenting molecular interactions with FLDP or Soluplus. The enhanced dissolution rate of binary or ternary Soluplus-rich ASDs in the nonsink condition of 0.05% SDS was achieved. Bottom-up approach indicated that Soluplus was a much stronger crystal inhibitor to the supersaturated FLDP in solutions than SDS. Top-down approach demonstrated that SDS enhanced the dissolution of Soluplus-rich ASDs via wettability and complexation with Soluplus to accelerate the medium uptake and erosion kinetics of extrudates, but induced FLDP recrystallization and resulted in incomplete dissolution of FLDP-rich extrudates. In conclusion, top-down approach is a promising strategy to explore the mechanisms of ASDs' dissolution, and small amount of SDS enhances the dissolution rate of polymer-rich ASDs in the nonsink condition.  相似文献   
8.
Two new saponins, notoginsenosides Ng1 (1) and Ng2 (2), together with seven known compounds (3–9), were isolated from the leaves of Panax notoginseng. Their structures were elucidated by UV, IR, HRESIMS, and NMR experiments. Compounds 6 and 7 showed moderate cytotoxic activities against HCT-116, with IC50 values of 4.98 and 0.64 μmol/L, respectively.  相似文献   
9.
Two new flavonol glycosides, bootanenside I and II (1 and 2), along with ten known compounds (312), were isolated from whole plant of Liparis bootanensis Griff. Their structures were elucidated on the basis of extensive spectroscopic analyses, including high-resolution electrospray-ionization mass spectrometry (HR–ESIMS) and one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR). The cytotoxicity of the compounds was investigated against HCT116 human cancer cell line, revealing that none of them possessed considerable cytotoxic activity. Bioassays of the new metabolites showed that compounds 1 and 2 displayed moderate in vitro antiinflammatory activity by inhibiting expression of inducible nitric oxide synthase (iNOS) protein in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells.  相似文献   
10.
Dairy consumption has been studied extensively in terms of its relationship with testicular cancer (TC), yet this relationship remains unclear. In this systematic review, we aimed to answer whether TC development is associated with (a) high amounts of dairy product consumption, (b) the type of dairy product consumed, (c) increasing levels of dairy product consumption, and (d) dairy consumption during certain periods during the lifecourse. Following a systematic review of the literature, eight studies (all case-control studies) were included in our review. The included studies varied in terms of the dairy product(s) investigated (milk, cheese, cream, butter, and yoghurt) as well as the type of exposure to dairy consumption (e.g., high vs. low exposure, dose-response, and timing during lifecourse). We found that there was no strong evidence that high levels of dairy consumption are associated with risk of TC, conflicting evidence of a dose–response relationship, inconsistent evidence on whether certain types of dairy are more strongly associated with TC than others, and conflicting evidence that exposure during certain life-course periods affects TC risk more than other periods. There is no consistent evidence to support the premise that dairy product consumption is associated with the risk of TC development.  相似文献   
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