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Objective: To explore the anti-diabetic effects and its underlying mechanism of Annona muricata Linn fruit ethanol extract (AME). Methods: Streptozotocin-induced type 2 diabetic (T2DM) mouse model was constructed. Those diabetic mice were randomly grouped and given 50 mg/kg acarbose or AME (200 mg/kg, 100 mg/kg or 50 mg/kg) for four weeks. The body weight, postprandial blood glucose and glycosylated hemoglobin levels were measured during the administration. After the administration, a glucose tolerance test was performed, and the levels of triglycerides, cholesterol and low-density lipoproteins in mice were detected by biochemical test kits. The inhibitory activity of AME on α-glucosidase in vivo and in vitro was determined by enzyme inhibition tests. Results: AME significantly reduced weight gain, postprandial blood glucose, glycosylated hemoglobin and low-density lipoprotein levels in T2DM mice; enhanced glucose tolerance and pancreatic β-cell function of T2DM mice; inhibited α-glucosidase activity in mouse intestine in an noncompetitive manner. Conclusion: AME may noncompetitive inhibit α-glucosidase activity and reduce postprandial glucose intake to achieve a therapeutic and regulatory effect on type 2 diabetes. [ABSTRACT FROM AUTHOR]

Objective: To investigate the anti-diabetic effect of the root extract of Annona muricata (AME) in streptozotocin-nicotinamide-induced type 2 diabetic (T2DM) mice. Methods: After 4 weeks of high-fat diet, ICR mice were given 1 g/kg nicotine and 120 mg/kg streptozotocin (STZ) orally to construct a T2DM model. The T2DM mice were randomly divided into five groups: model group, 200 mg/kg metformin group and 50, 100, 200 mg/kg AME groups. Drugs were oral administered continuously for 4 weeks. Fasting blood glucose and body weight were measured weekly. Oral glucose tolerance test (OGTT) and detection of serum glycated hemoglobin (HbA1c) level were performed one week before the end of the experiment. At the end of drug administration, serum total cholesterol (TG), triglycerides (TC), low-density lipoprotein levels (LDL-C) and insulin levels were tested by lipid detection kits; homeostasis model assessment-estimated insulin resistance (HOMA-IR) and HOMA-β indexes were calculated. Liver and kidney tissues were weighed to calculate organ indices and pathological tests were performed. Western blot was performed in the liver to detect adenosine monophosphate-activated protein kinase (AMPK), acetyl coenzyme A carboxylase (ACC), glucose-6-phosphate carboxylase (G6Pase), and phosphoenolpyruvate carboxykinase (PCK1) protein expression. Results: with 200 mg/kg AME significantly reduced fasting blood glucose, HbA1c, TG and LDL-C levels, protected liver and kindey in diabetic mice, decreased the area under the OGTT curve, inhibited ACC and G6Pase protein expressions, and activated AMPK protein expression. Conclusion: AME showed good therapeutic activity against T2DM, and the mechanism may be related to the activation of AMPK and inhibition of ACC and G6Pase proteins. [ABSTRACT FROM AUTHOR]

A bandwidth-reconfigurable filter is necessary to meet the need of growing communication capacity and signal coverage frequency range. The stimulated Brillouin scattering (SBS) gain spectrum as a filter passband is used to extract desired microwave signals. Due to the fact that the passband is formed by mapping the Brillouin gain spectrum, bandwidth reconfigurability can be implemented by changing Brillouin gain linewidth. In this paper, a scheme using a 5-lines optical comb acting as a Brillouin pump is experimentally demonstrated. The spectrum of the 5-lines optical comb is extended by a binary phase shift keying (BPSK) pulse modulated signal. Experiments have shown that the 3-dB and 20-dB bandwidths of the filter are 196 MHz and 257 MHz, respectively, and its 20-dB shape factor is 1.31. The passband ripple is ~3.5 dBm with stop-band rejection of 20 dBm under 15 dBm optical pump power. [ABSTRACT FROM AUTHOR]

Purpose: To introduce a novel practical technique of self-made cryopreservative fibrin glue (SMC) applied in pterygium surgery and to assess its safety and efficacy.Methods: Forty-eight eyes of 48 patients with nasal primary pterygium were enrolled. The patients were equally assigned to 6 groups. Self-made fibrin glue was subpackaged and, respectively, cryopreserved for 3, 7, 15 days and 1, 2 and 3 months. At each time point, the asepsis of SMC was confirmed by bacterial culture and colony counting. In each group, corresponding SMC was applied to fix the autograft after the pterygium was removed (e.g., SMC 3d for group 1 and SMC 3m for group 6). All the patients were followed up postoperatively on days 1, 3, 7 and 14 and then at months 1, 3, 6. The main outcome measures included fixation success rate within two tries, postoperative discomfort, recurrence rate and complications.Results: No colony growth was observed in all the fibrinogen and thrombin tubes sent. Five patients needed a second try with respective SMC during the autograft fixation, and there were no significant differences in SMC use times among the groups (P = 0.885). There were no significant differences in postoperative discomfort (day 1, 3, 7; P = 0.651, P = 0.269, P = 0.180, respectively) among the groups. By the end of 6-m follow-up, no infections and severe complications were observed in any group. The total recurrence rate was 3/48 (6%), and there were no significant differences in recurrences among the groups (P = 1.000).Conclusion: SMC is safe and effective for autograft fixation in pterygium surgery. This new practical technique will benefit the patients and surgeons in developing and underdeveloped country. [ABSTRACT FROM AUTHOR]

The electrochemical treatment of COD contained in biologically pretreated coking wastewater treated by a three-dimensional electrode system with modified coke as the particle electrode was investigated. And the electrochemical perfomance of the coke modified with various active components was studied. The results show that the coke modified with Fe(NO) has the lowest energy consumption and higher COD removal rate under the same condition, and the modified coke has better surface characteristics for the purpose of this study. In addition, the kinetic constant was also calculated. The study shows that the three-dimensional electrode system with Fe (NO)-modified coke can give a satisfactory solution in biologically pretreated coking wastewater. [ABSTRACT FROM AUTHOR]

The aim of the present study was to develop a rapid, specific and sensitive LC–MS/MS method for the determination of DPHB [7‐(4″‐hydroxy‐3″‐methoxyphenyl)‐1‐phenyl‐4‐hepten‐3‐one] in rat plasma using yakuchinone A as an internal standard (IS). n‐Hexane was used for the extraction of DPHB from rat plasma. Chromatographic separation of DPHB was achieved using a Kinetex XB‐C18 column (2.10 × 50 mm, 2.6 μm) at 40°C. The mobile phase consisted of water (containing 0.1‰ formic acid, A) and acetonitrile (containing 0.1‰ formic acid, B) under a gradient elution at a flow rate of 0.3 mL min−1. Positive electrospray ionization and multiple reaction monitoring mode were used for detection. The selected precursor ion to product ion pairs, m/z 311.3 → 137.0 for DPHB and m/z 313.1 → 137.0 for yakuchinone A, were monitored. Good linearity was observed over the concentration range from 2 to 2000 ng mL−1 (r = 0.9969). The recovery efficiency of DPHB from rat plasma was 54.8–69.7%, while the matrix effect ranged from 99.7 to 113%. Intra‐ and inter‐day precision and accuracy values were within ±15% at three different quality control concentration levels. This validated method was successfully applied to pharmacokinetic studies in rats after a single p.o. or i.v. dose of DPHB solution. The route of administration significantly influenced systemic exposure to DPHB, and low bioavailability of DPHB was observed. The method developed here will be further improved and used in future pharmacokinetic studies. [ABSTRACT FROM AUTHOR]