Clarithromycin- and omeprazole-containing gliadin nanoparticles for the treatment of Helicobacter pylori

The aim of the present work was to prepare and evaluate the oral mucoadhesive sustained release nanoparticles of clarithromycin and omeprazole in order to improve patient compliance by improving its therapeutic effect and reducing its dose-related side effects. The clarithromycin- and omeprazole-containing gliadin nanoparticles were prepared by the desolvation method using Pluronic F-68 as a stabilizing agent. The results showed that this method is reproducible, easy, and leads to the efficient entrapment of drug as well as formation of spherical particles ranging from 400 to 650 nm. The maximum percentage of drug entrapment for clarithromycin and omeprazole was 81.7 +/- 2.2 and 73.7 +/- 3.9%, respectively, whereas the percentage of yield of the system was 85.1 +/- 1.9%. The sustained release behavior of gliadin nanoparticles was evaluated in phosphate-buffered saline (pH 7.4) and simulated gastric fluid (pH 1.2), at 37 +/- 1 degrees C. Their mucoadhesive properties were determined by in vitro and in vivo methods. In vitro antibacterial activity of the formulations was performed on isolated culture of Helicobacter pylori, which showed greater eradication effect of dual therapy entrapped formulations when compared with single therapy containing formulations and plain drugs.     

A joint model for interval‐censored functional decline trajectories under informative observation

Multi‐state models are useful for modelling disease progression where the state space of the process is used to represent the discrete disease status of subjects. Often, the disease process is only observed at clinical visits, and the schedule of these visits can depend on the disease status of patients. In such situations, the frequency and timing of observations may depend on transition times that are themselves unobserved in an interval‐censored setting. There is a potential for bias if we model a disease process with informative observation times as a non‐informative observation scheme with pre‐specified examination times. In this paper, we develop a joint model for the disease and observation processes to ensure valid inference because the follow‐up process may itself contain information about the disease process. The transitions for each subject are modelled using a Markov process, where bivariate subject‐specific random effects are used to link the disease and observation models. Inference is based on a Bayesian framework, and we apply our joint model to the analysis of a large study examining functional decline trajectories of palliative care patients. Copyright © 2015 John Wiley & Sons, Ltd.     

Ethnopharmacology,phytochemistry and pharmacology of Tephrosia purpurea简

Tephrosiapurpurea （L.） Pers. is popularly known as ＇Sarapunkha＂ in classical Ayurvedic texts. It is a perennial plant belonging to the family Fabaceae, and occurs throughout the Indian subcontinent. T. purpurea is traditionally used to treat spleenomegaly, cirrhosis, cough and cold, abdominal swelling and as an antidote in the Ayurvedic system of medicine. Phytochemical investigations indicate the presence of semiglabrin, pongamole, lanceolatins A and B, rutin, lupeol, and β-sitosterol. Flavonoids including （＋）-tephrorin A and B, （＋）-tephrosone, an isoflavone, 7, 4＇-dihydroxy-3＇, 5＇-dimethoxyisoflavone and a chalcone, （＋）-tephropurpurin were isolated from the whole plant. Pharmacological activities of different parts of the plant reported include anti-inflammatory, antiulcer, antimicrobial, antioxidant, antiallergic, antidiabetic, hepatoprotective, antitumor and insect repellent activity. In the present review, the literature on the phytochemical and pharmacological investigations of Tephrosia purpurea （L.） Pers. are summarized to August, 2012.     

Time series analysis of fMRI data: Spatial modelling and Bayesian computation

Time series analysis of fMRI data is an important area of medical statistics for neuroimaging data. Spatial models and Bayesian approaches for inference in such models have advantages over more traditional mass univariate approaches; however, a major challenge for such analyses is the required computation. As a result, the neuroimaging community has embraced approximate Bayesian inference based on mean‐field variational Bayes (VB) approximations. These approximations are implemented in standard software packages such as the popular statistical parametric mapping software. While computationally efficient, the quality of VB approximations remains unclear even though they are commonly used in the analysis of neuroimaging data. For reliable statistical inference, it is important that these approximations be accurate and that users understand the scenarios under which they may not be accurate. We consider this issue for a particular model that includes spatially varying coefficients. To examine the accuracy of the VB approximation, we derive Hamiltonian Monte Carlo (HMC) for this model and conduct simulation studies to compare its performance with VB in terms of estimation accuracy, posterior variability, the spatial smoothness of estimated images, and computation time. As expected, we find that the computation time required for VB is considerably less than that for HMC. In settings involving a high or moderate signal‐to‐noise ratio (SNR), we find that the 2 approaches produce very similar results suggesting that the VB approximation is useful in this setting. On the other hand, when one considers a low SNR, substantial differences are found, suggesting that the approximation may not be accurate in such cases and we demonstrate that VB produces Bayes estimators with larger mean squared error. A comparison of the 2 computational approaches in an application examining the hemodynamic response to face perception in addition to a comparison with the traditional mass univariate approach in this application is also considered. Overall, our work clarifies the usefulness of VB for the spatiotemporal analysis of fMRI data, while also pointing out the limitation of VB when the SNR is low and the utility of HMC in this case.     

Clinical and in vitro evidence for the efficacy of Australian red-back spider (Latrodectus hasselti) antivenom in the treatment of envenomation by a Cupboard spider (Steatoda grossa).

We report the case of a 22-year-old female who was bitten on the shoulder by a spider subsequently identified as a female Cupboard spider (Steatoda grossa). She developed nausea, vomiting, and severe local and regional pain, similar to that seen in latrodectism. Symptoms were treated successfully with red-back spider antivenom (RBSAV). We also present in vitro data, which supports this clinical observation, and suggests that S. grossa venom is immunogenically reactive with both RBSAV and latrotoxin (LTx)-specific antibodies by Western blotting. Moreover, the effects of S. grossa venom on the isolated chick biventer cervicis nerve-muscle preparation are dose-dependent and similar to those seen with Latrodectus spp. venoms. S. grossa venom produced a sustained muscle contracture which could be prevented by pre-incubation of venom with RBSAV. Venom effects could also be reversed by the addition of antivenom after application of venom to the preparation.Although severe envenomation is uncommon following the bite of Steatoda spp. it may resemble latrodectism. These results indicate that RBSAV is likely to be effective in reversing symptoms of envenomation and should be considered in the treatment of patients with distressing or persisting symptoms.     

Effect of postpartum maternal or neonatal vitamin A supplementation on infant mortality among infants born to HIV-negative mothers in Zimbabwe

BACKGROUND: Young infants are at risk of vitamin A deficiency. Supplementation of breastfeeding mothers improves the vitamin A status of their infants, but there are no data regarding its effect on infant mortality, and data on the effect of directly supplementing infants during the first few weeks of life are conflicting. OBJECTIVE: The objective was to measure the effect on infant mortality of supplementing neonates and their HIV-negative mothers with single, large doses of vitamin A during the immediate postpartum period. DESIGN: A randomized, placebo-controlled, 2-by-2 factorial design trial was conducted in 14,110 mothers and their infants; 9208 of the mothers were HIV-negative at delivery, remained such during the postpartum year, and were retained in the current analysis. The infants were randomly assigned within 96 h of delivery to 1 of 4 treatment groups: mothers and infants received vitamin A (Aa), mothers received vitamin A and infants received placebo (Ap), mothers received placebo and infants received vitamin A (Pa), and both mothers and infants received placebo (Pp). The vitamin A dose in the mothers was 400,000 IU and in the infants was 50,000 IU. The mother-infant pairs were followed to 12 mo. RESULTS: Hazard ratios (95% CI) for 12 mo mortality among infants in the maternal-supplemented and infant-supplemented groups were 1.17 (0.87, 1.58) and 1.08 (0.80, 1.46), respectively. Hazard ratios (95% CI) for the Aa, Ap, and Pa groups compared with the Pp group were 1.28 (0.83, 1.98), 1.27 (0.82, 1.97), and 1.18 (0.76, 1.83), respectively. These data indicate no overall effect. Serum retinol concentrations among a subsample of women were similar to reference norms. CONCLUSION: Postpartum maternal or neonatal vitamin A supplementation may not reduce infant mortality in infants of HIV-negative women with an apparently adequate vitamin A status.     

Solubility Enhancement of Indomethacin with Poly(amidoamine) Dendrimers and Targeting to Inflammatory Regions of Arthritic Rats

This work includes investigation on solubility enhancement of indomethacin (IND) in the presence of poly(amidoamine) (PAMAM) dendrimers and passive targeting of the PAMAM/IND complex so formed to the inflamed regions in an animal model. The complex formation was confirmed by infrared and ¹H nuclear magnetic resonance spectroscopy methods. Solubility of IND in aqueous G4-PAMAM followed Higuchi's A_N curve depending on pH of the solubilizing medium. The solubility was decreased upon addition of dendrimer to the IND saturated solution at various pH, indicating aggregation behavior of the PAMAM/IND complex and conforming to the Higuchi's A_N solubility profile. The in vitro release of IND from the PAMAM/IND complex through a cellophane membrane, from a Franz diffusion cell, showed 79±3.2% drug release in 24 h. The drug release was further retarded in the presence of human serum albumin (HSA) suggesting the significance of complex HSA binding in altering in vivo behavior of the complex. Intravenous administration of the PAMAM/IND complex formulation in rats showed a two-compartment pharmacokinetic profile. Enhanced effective IND concentrations in the inflamed regions were obtained for the prolonged time period with the PAMAM/IND complex compared to the free drug in arthritic rats indicating preferred accumulation of IND to the inflamed region. The targeting efficiency of PAMAM/IND complex was 2.29 times higher compared to free drug. In contrast to the previous investigations, two interesting findings reported here are: (a) solubility behavior of IND in G4-PAMAM dendrimer deviates from linearity with increasing concentrations of dendrimer at acidic to neutral pH values and (b) inspite of lymphatic drainage, retention of PAMAM/IND complexes occurs at the inflammatory site.     

Long circulating PEGylated poly(d,l-lactide-co-glycolide) nanoparticulate delivery of Docetaxel to solid tumors

Purpose: The aim of this study was to investigate the ability of PEGylated poly(d,l-lactide-co-glycolide) nanoparticles (NPs) to deliver Docetaxel (DTX) (an anticancer agent) to solid tumors.

Methods: PLGA–mPEG diblock copolymers were synthesized by ring opening polymerization reaction and characterized by ¹H NMR, FT-IR and gel permeation chromatography. NPs, with a smooth spherical shape and near 100 nm size were prepared using the emulsion solvent evaporation technique and characterized. The drug release rate was investigated in acidic and physiological media (phosphate buffer saline, pH 5.0 and 7.4). The therapeutic efficacy and biocompatibility of NP formulations were evaluated for in vitro cytotoxicity by MTT assay using MCF-7 and C26 cell lines. The pharmacokinetic and biodistribution studies were performed on C26 tumor bearing mice. The antitumor efficacy of DTX NP formulations on C26 tumor bearing mice was investigated.

Results: DTX-loaded PEGylated NPs increased the drug's biological half-life while providing substantial accumulation at the solid tumors. PEGylated NPs appear to be a promising alternate carrier for DTX having greater efficacy in inhibiting tumor growth.     

HIV-1 and HIV-2 prevalence and associated risk factors among postnatal women in Harare, Zimbabwe

Studies of antenatal women form the predominant source of data on HIV-1 prevalence in Africa. Identifying factors associated with prevalent HIV is important in targeting diagnostic services and care. Between November 1997 and January 2000, 14,110 postnatal women from Harare, Zimbabwe were tested by ELISAs reactive to both HIV-1 and HIV-2; a subset of positive samples was confirmed with assays specific for HIV-1 and HIV-2. Baseline characteristics were elicited and modelled to identify risk factors for prevalent HIV infection. HIV-1 and HIV-2 prevalences were 32.0% (95% CI 31.2-32.8) and 1.3% (95% CI 1.1-1.5), respectively; 4% of HIV-1-positive and 99% of HIV-2-positive women were co-infected. HIV-1 prevalence increased from 0% among 14-year-olds to >45% among women aged 29-31 years, then fell to <20% among those aged>40 years. In multivariate analyses, prevalence increased with parity, was lower in married women than in single women, divorcees and widows, and higher in women with the lowest incomes and those professing no religion. Adjusted HIV-1 prevalence increased during 1998 and decreased during 1999. Age modified the effects of parity, home ownership and parental education. Among older women, prevalence was greater for women who were not homeowners. Among younger women, prevalence increased with parity and low parental education. None of these factors distinguished women co-infected with HIV-2 from those infected with HIV-1 alone. Prevalent HIV-1 infection is associated with financial insecurity and weak psychosocial support. The ZVITAMBO study apparently spanned the peak of the HIV-1 epidemic among reproductive women in Harare.     

Risk taking behavior of adolescents in Indonesia (country report)

Adolescent problems in Indonesia are becoming more and more relevant due to the increasing reports recently. Although data gathered are very limited a certain consideration should be well planned to get all resources in terms of motivation in paying more attention to the future of Indonesia youth problems such as narcotics/drug abuse, sexual activities including sexual transmitted diseases etc. A good communication with the other Asian countries in controlling those risk taking behaviors in adolescent will be very promising to gain the improvement of people's life quality by the year 2,000.