Less of insulin desensitization in sympathetic nerve terminals from wistar rats with insulin resistance

In an attempt to determine the effect of hyperinsulinemia on sympathetic function, release of norepinephrine (NE) from isolated aorta by insulin was measured in Wistar rats with insulin resistance. Insulin resistance was produced when the hypoglycemic action of glibenclamide at a dose of 10 mg/kg was almost abolished in rats that received daily injections of long-acting insulin for 15 days. Moreover, the stimulatory effect of insulin on glucose uptake was markedly reduced in both skeletal muscle strips and white adipocytes obtained from these rats with insulin resistance. However, the stimulatory effects of insulin at concentrations from 5 to 15 U/l on the release of NE from the aortic strip of insulin-resistant rats were not modified in the same manner but only slightly reduced compared with that of normal rats. These results suggest that insulin desensitization was produced later in sympathetic nerve terminals than in other organs in insulin-resistant rats and this may be helpful to explain the sympathetic hyperactivity associated with diabetes in clinics.     

Randomized phase II study of two doses of gefitinib in hormone-refractory prostate cancer: a trial of the National Cancer Institute of Canada-Clinical Trials Group.

PURPOSE: Overexpression of the epidermal growth factor receptor has been demonstrated in advanced prostate cancer and is associated with a poor outcome. A multi-institutional, randomized, phase II study was undertaken by the National Cancer Institute of Canada-Clinical Trials Group to evaluate the efficacy and toxicity of two doses of oral gefitinib in patients with minimally symptomatic, hormone-refractory prostate cancer (HRPC). PATIENTS AND METHODS: Between July and November 2001, 40 patients with HRPC and increasing prostate-specific antigen (PSA) or progression in measurable disease who had not received prior chemotherapy were randomly assigned to 250 mg (n = 19) or 500 mg (n = 21) oral gefitinib daily continuously. The primary end points were PSA response rate and objective measurable response. Functional Assessment of Cancer Therapy Prostate Cancer Subscale (FACT-P) quality-of-life questionnaires were completed at baseline and during treatment. RESULTS: None of the patients demonstrated a PSA or objective measurable response. Five (14.3%) of 35 assessable patients had stable PSA (one patient at 250 mg and four patients at 500 mg), and five patients (14.3%) had a best response of stable disease (duration, 2.5 to 16.8 months). No significant effect on the rate of increase in PSA was seen. The most common drug-related nonhematologic toxicities observed were grade 1 to 2 diarrhea (250 mg, 65%; 500 mg, 56%), fatigue (250 mg, 29%; 500 mg, 33%), and grade 1 to 2 skin rash (250 mg, 24%; 500 mg, 39%). FACT-P scores decreased during treatment, indicating worsening of symptoms compared with baseline. CONCLUSION: Gefitinib did not result in any responses in PSA or objective measurable disease at either dose level. Gefitinib has minimal single-agent activity in HRPC.     

Intraoperative choroidal detachment during small-gauge vitrectomy: analysis of causes,anatomic, and visual outcomes

IntroductionTo investigate the incidence and causes of intraoperative choroidal detachment (CD) during small-gauge vitrectomy, as well as the anatomic and visual outcomes.MethodsWe retrospectively reviewed the medical records of 1026 consecutive patients who underwent small-gauge vitrectomy from June 2017 to December 2018 at Zhongshan Ophthalmic Centre, Guangzhou, China. Data on the presence, location, and extent of intraoperative CD and its relationship to the infusion cannula were collected. Patient demographic characteristics and postoperative anatomic and visual outcomes were also assessed.ResultsA total of six cases were found to have intraoperative CD, including two with serous CD, three with limited haemorrhagic CD, and one with CD caused by inadvertent perfusion of gas during air/fluid exchange. Retraction of the infusion cannula and acute ocular hypotony were found to be the main causes of intraoperative CD in five out of the six cases. The best-corrected visual acuity of all cases significantly improved after the surgery.ConclusionThe incidence of intraoperative CD during small-gauge vitrectomy is low; the predominant causes are retraction of the infusion cannula and acute ocular hypotony. Immediate awareness and timely closure of the incision may contribute to a better surgical prognosis.Subject terms: Uveal diseases, Diseases     

Pharmacological effects of green tea on the gastrointestinal system

Green tea is rich in polyphenolic compounds, with catechins as its major component. Studies have shown that catechins possess diverse pharmacological properties that include anti-oxidative, anti-inflammatory, anti-carcinogenic, anti-arteriosclerotic and anti-bacterial effects. In the gastrointestinal tract, green tea was found to activate intracellular antioxidants, inhibit procarcinogen formation, suppress angiogenesis and cancer cell proliferation. Studies on the preventive effect of green tea in esophageal cancer have produced inconsistent results; however, inverse relationships of tea consumption with cancers of the stomach and colon have been widely reported. Green tea is effective to prevent dental caries and reduce cholesterols and lipids absorption in the gastrointestinal tract, thus benefits subjects with cardiovascular disorders. As tea catechins are well absorbed in the gastrointestinal tract and they interact synergistically in their disease-modifying actions, thus drinking unfractionated green tea is the most simple and beneficial way to prevent gastrointestinal disorders.     

两种给药途径致痫大鼠海马神经元超微结构损伤及caspase-3的表达特征

为了观察两种给药途径致痫大鼠海马神经元超微结构的损伤及caspase-3的表达特征,本研究分别采用海人酸腹膜腔注射(A组)和尾静脉注射(B组)诱发大鼠癫痫持续状态(SE)。分别于SE终止后3、6、24、48和72h取海马,电镜观察神经元超微结构的变化,免疫组化方法检测caspase-3的表达。结果显示:两组大鼠均在SE后3h出现线粒体损伤,细胞核的改变出现于SE后24h。A组致痫的潜伏期为97min±11min,神经元以凋亡为主;B组为48min±13min,神经元以坏死为主。SE后6～24h,两组大鼠海马内caspase-3的表达由胞浆向胞核逐渐移位,且均在SE后6h明显增高,24h达顶峰;A组高表达持续至72h,B组在48h显著降低。上述结果提示,线粒体的损伤出现于SE的早期,且可能是神经元损伤的关键环节;致痫方法不同,神经元的死亡形式也不同;而caspase-3的激活是神经元凋亡和坏死的共同通路。     

Lignin-based composites for high-performance supercapacitor electrode materials

With the rapid development of the global economy, the depletion of fossil fuels and the intensification of environmental pollution, there is an increasingly urgent need for new and green electrochemical energy storage technologies in society. In this thesis, ligninsulfonate/polyaniline nanocomposites were synthesized by in situ chemical oxidation using aniline as the monomer, lignin as the template and dopant, and ammonium persulfate as the oxidant. The results showed that the average diameter of the ligninsulfonate/polyaniline nanocomposite was 85 nm, and the composite electrode exhibited good electron conduction ability and excellent capacitive performance by ligninsulfonate doping. The electrode material showed the best electrochemical performance when the ligninsulfonate addition was 0.1 g. The specific capacitance can reach 553.7 F g⁻¹ under the current density of charge/discharge 1 A g⁻¹, which is higher than that of the pure PANI electrode. The composite electrode material has good multiplicative performance and cycling stability, and the capacitance retention rate can be maintained at 68.01% after 5000 cycles at a charge/discharge current density of 10 A g⁻¹ (three-electrode system), and the capacitance retention rate can be maintained at 54.84% after 5000 cycles at a charge/discharge current density of 5 A g⁻¹ (two-electrode system).

The lignosulfonate/polyaniline nanocomposite electrode material was made by polymerization of aniline with lignosulfonate as dispersant and structure-directing agent. Redox can convert the catechol/quinone groups on lignin, promoted by electron transfer of polyaniline.