Injury of skeletal muscle and specific cytokines induce the expression of gap junction channels in mouse dendritic cells

Dendritic cells (DCs) in culture express at least connexin43, a protein subunit of gap junctions, and form gap junction channels, which could be important for T-cells activation. Here, we evaluated whether DCs express connexins in vivo and also to identify components of their microenvironment that regulate the functional expression of gap junctions. In vivo studies were performed in lymph nodes of mice under control conditions or after skeletal muscle damage. In double immunolabeling studies, connexin45 was frequently detected in DEC205(+) DCs in lymph nodes of control animals, whereas connexin43 was rarely found in DCs. However, connexin43 was upregulated in DCs after skeletal muscle damage. Upregulation of connexin43 gene expression by tissue damage was also confirmed in mice carrying a beta-galactosidase reporter gene in a connexin43 allele. The effect of several cytokines on the expression of functional gap junctions between cultured DCs was also tested. Under control conditions, cultured DCs did not communicate via gap junctions. However, after treatment with keratinocyte-conditioned medium or cytokine mixtures containing at least TNF-alpha and IL-1beta, they became transiently coupled through a pathway sensitive to octanol, a gap junction blocker. Cellular coupling induced by effective cytokine mixtures was prevented by IL-6. Single cytokines (TNF-alpha, IL-1beta, IFN-gamma, or IL-6) or other mixtures than the described above did not induce coupling via gap junctions. Increased levels of connexin43 and connexin45 protein and mRNA accompanied the appearance of cellular coupling. These studies provide demonstration of connexin expression and regulation by specific danger signals in DCs.     

Effects of prolonged stanozolol treatment on antioxidant enzyme activities, oxidative stress markers, and heat shock protein HSP72 levels in rat liver

The abuse of anabolic-androgenic steroids (AAS) to enhance physical performance is widespread in sport communities despite their reported side effects. Since the biochemical bases for the hepatotoxic effects of these compounds are largely unknown, this investigation was aimed at testing whether prolonged (8 weeks) treatment with high doses (2 mg kg⁻¹ body weight; 5 d wk⁻¹) of stanozolol (ST), either alone or in conjunction with treadmill-exercise training, induced changes in oxidative stress biomarker levels and antioxidant defence systems in rat liver. After ST oral administration, the mean values of serum parameters related to hepatic function were within normal ranges. No changes in protein carbonyl content and in the reduced to oxidized glutathione (GSH/GSSG) ratio were detected in liver homogenates of ST-treated rats, whereas thiobarbituric acid-reactive substances (TBARS) levels resulted increased (P<0.05). Total superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities were higher (P<0.05) in the liver of treated rats but mitochondrial SOD and glutathione reductase (GR) activities, and the 72 kDa heat shock protein (HSP72) level were not modified. Chronic exercise alone did not change any of the above parameters except for a remarkable enhancement of HSP72 expression; in no case training modified the effects of ST treatment. The present data show that 8 wk ingestion of ST, either with or without concurrent exercise training, can induce oxidative stress in rat liver despite the up-regulation of enzymatic antioxidant activities.     

5α,8α-Epidioxysterols from the gorgonian Eunicella cavolini and the ascidian Trididemnum inarmatum: Isolation and evaluation of their antiproliferative activity

Three new (1, 4, 9) and nine previously reported (2, 3, 5-8, 10-12) 5α,8α-epidioxysterols were isolated from the organic extracts of the gorgonian Eunicella cavolini and the ascidian Trididemnum inarmatum. The structures and relative configurations of 1-12 were established on the basis of detailed NMR spectroscopic analyses and comparison with the literature. The growth inhibitory effects of 1-12 were evaluated against MCF-7 human breast cancer cells. Compound 1, bearing a cyclopropyl moiety in the side chain, exhibited the highest antiproliferative activity.     

HIV Cure Strategies: How Good Must They Be to Improve on Current Antiretroviral Therapy?

Background

We examined efficacy, toxicity, relapse, cost, and quality-of-life thresholds of hypothetical HIV cure interventions that would make them cost-effective compared to life-long antiretroviral therapy (ART).

Methods

We used a computer simulation model to assess three HIV cure strategies: Gene Therapy, Chemotherapy, and Stem Cell Transplantation (SCT), each compared to ART. Efficacy and cost parameters were varied widely in sensitivity analysis. Outcomes included quality-adjusted life expectancy, lifetime cost, and cost-effectiveness in dollars/quality-adjusted life year ($/QALY) gained. Strategies were deemed cost-effective with incremental cost-effectiveness ratios <$100,000/QALY.

Results

For patients on ART, discounted quality-adjusted life expectancy was 16.4 years and lifetime costs were $591,400. Gene Therapy was cost-effective with efficacy of 10%, relapse rate 0.5%/month, and cost $54,000. Chemotherapy was cost-effective with efficacy of 88%, relapse rate 0.5%/month, and cost $12,400/month for 24 months. At $150,000/procedure, SCT was cost-effective with efficacy of 79% and relapse rate 0.5%/month. Moderate efficacy increases and cost reductions made Gene Therapy cost-saving, but substantial efficacy/cost changes were needed to make Chemotherapy or SCT cost-saving.

Conclusions

Depending on efficacy, relapse rate, and cost, cure strategies could be cost-effective compared to current ART and potentially cost-saving. These results may help provide performance targets for developing cure strategies for HIV.     

Refinement of the locus for autosomal dominant cerebellar ataxia type II to chromosome 3p21.1–14.1

We have previously mapped the gene for autosomal dominant cerebellar ataxia type II (ADCAII) to chromosome 3p12-p21.1 in a region of 33 cM by using four families of different geographic origin. In this study, we analysed the families with nine additional simple tandem repeat markers located in the ADCAII candidate region. An extensive clinical evaluation was also performed in the Belgian family CA-1 on two probably affected and seven at-risk individuals by means of ophthalmological examination and magnetic resonance imaging. Based on informative recombinants, we were able to reduce the ADCAII candidate region to the 12-cM region between D3S1300 and D3S1285. Furthermore, haplotype analysis among the families suggested that the most likely location of the ADCAII gene is within the 6.2-cM interval between D3S3698 and D3S1285. Because of the documented anticipation in ADCAII families, we also analysed family CA-1 with six polymorphic triplet repeat markers located on chromosome 3. None of these markers showed expanded alleles. Received: 16 August 1996 / Revised: 7 October 1996     

On the karyotype of the tahr Hemitragus jemlahicus and the Y-chromosome of goats and sheep

Somatic chromosomes of a female and male Himalayan thar, Hemitragus jemlahicus (H. Smith) are described. The diploid number is 48, there are 12 atelocentric and 34 telocentric autosomes in both sexes, the X-chromosome is meta- or submetacentric. The morphological appearance of the Y-chromosome is compared with that of other bovid species including recent observations on the goat Capra hircus.Supported by Contract No. PH 43-63-13 between the National Cancer Institute of the National Institutes of Health and the University of California.     

Comparative characterization of endo-polygalacturonase (<Emphasis Type="Italic">Pgu1</Emphasis>) from <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis> and <Emphasis Type="Italic">Saccharomyces paradoxus</Emphasis> under winemaking conditions

A peptide antibiotic, gramicidin A, was covalently bound to cystamine self-assembled monolayers on gold surfaces. Each step of the surface functionalization was characterized by polarization modulation infrared reflection absorption spectroscopy and X-ray photoelectron spectroscopy. The antimicrobial activity of the anchored gramicidin was tested against three Gram-positive bacteria (Listeria ivanovii, Enterococcus faecalis, and Staphylococcus aureus), the Gram-negative bacterium Escherichia coli and the yeast Candida albicans. The results revealed that the adsorbed gramicidin reduced, from 60% for E. coli to 90% for C. albicans, the number of culturable microorganisms attached to the surface. The activity was proven to be persistent overtime, up to 6 months after the first use. The bacteria attached to the functionalized surfaces were permeabilized as shown by confocal microscopy. Taken together, these results indicate a bacteriostatic mode of action of the immobilized peptide. Finally, using green fluorescent protein-expressing bacteria, it was shown that the development of a bacterial biofilm was delayed on peptide-grafted surfaces for at least 24 h.     

NL MIND-BEST: a web server for ligands and proteins discovery--theoretic-experimental study of proteins of Giardia lamblia and new compounds active against Plasmodium falciparum

There are many protein ligands and/or drugs described with very different affinity to a large number of target proteins or receptors. In this work, we selected Ligands or Drug-target pairs (DTPs/nDTPs) of drugs with high affinity/non-affinity for different targets. Quantitative Structure-Activity Relationships (QSAR) models become a very useful tool in this context to substantially reduce time and resources consuming experiments. Unfortunately most QSAR models predict activity against only one protein target and/or have not been implemented in the form of public web server freely accessible online to the scientific community. To solve this problem, we developed here a multi-target QSAR (mt-QSAR) classifier using the MARCH-INSIDE technique to calculate structural parameters of drug and target plus one Artificial Neuronal Network (ANN) to seek the model. The best ANN model found is a Multi-Layer Perceptron (MLP) with profile MLP 20:20-15-1:1. This MLP classifies correctly 611 out of 678 DTPs (sensitivity=90.12%) and 3083 out of 3408 nDTPs (specificity=90.46%), corresponding to training accuracy=90.41%. The validation of the model was carried out by means of external predicting series. The model classifies correctly 310 out of 338 DTPs (sensitivity=91.72%) and 1527 out of 1674 nDTP (specificity=91.22%) in validation series, corresponding to total accuracy=91.30% for validation series (predictability). This model favorably compares with other ANN models developed in this work and Machine Learning classifiers published before to address the same problem in different aspects. We implemented the present model at web portal Bio-AIMS in the form of an online server called: Non-Linear MARCH-INSIDE Nested Drug-Bank Exploration & Screening Tool (NL MIND-BEST), which is located at URL: http://miaja.tic.udc.es/Bio-AIMS/NL-MIND-BEST.php. This online tool is based on PHP/HTML/Python and MARCH-INSIDE routines. Finally we illustrated two practical uses of this server with two different experiments. In experiment 1, we report by first time Quantum QSAR study, synthesis, characterization, and experimental assay of antiplasmodial and cytotoxic activities of oxoisoaporphine alkaloids derivatives as well as NL MIND-BEST prediction of potential target proteins. In experiment 2, we report sampling, parasite culture, sample preparation, 2-DE, MALDI-TOF, and -TOF/TOF MS, MASCOT search, MM/MD 3D structure modeling, and NL MIND-BEST prediction for different peptides a new protein of the found in the proteome of the human parasite Giardia lamblia, which is promising for anti-parasite drug-targets discovery.