Genetic variability in the 5' UTR and NS5A regions of hepatitis C virus RNA isolated from non-responding and responding patients with chronic HCV genotype 1 infection

Sequence variation among different hepatitis C virus (HCV) isolates has adaptive significance and reflects the modes and intensities of selection mechanisms operating on the virus. In this work, we sought to investigate using classical population genetics parameters, the genetic variability of HCV genotype 1 using the 5' UTR and NS5A regions from treatment non-responding and responding groups of patients. Both regions showed low genetic varia-bility and the 5' UTR showed neutral deviation. No differences were observed in the nonsynonymous/synonymous nucleotide substitution ratio among groups for NS5A. The analysis of molecular variance test of the 5' UTR region showed an 11.94% variation among groups. Phylogenetic analysis showed no correlation between sequence variations and therapeutic responses.

Enterotoxigenic and nontoxigenic Bacteroides fragilis strains isolated in Brazil

The presence of enterotoxigenic Bacteroides fragilis and nontoxigenic B. fragilis (NTBF) among 109 strains isolated from 1980-2008 in Brazil were investigated by PCR. One strain, representing 0.9% of the total analyzed strains, harbored the bft gene which was identified as bft-1 isoform based on PCR-RFLP and sequencing. Forty-nine strains (44.9%) exhibited the NTBF pattern III which possesses the flanking region required for pathogenicity island acquisition in which the bftgene is codified. These data reinforce the potential of B. fragilis as an emerging enteropathogen in our country.

Isolated congenital atrioventricular block diagnosed in utero: natural history and outcome.

BACKGROUND: Isolated congenital atrioventricular block (CAVB) diagnosed in utero is associated with a high morbidity and mortality. Prognosis is especially poor when heart rate drops below 55 beats per minute (bpm) and when fetal hydrops develops. We describe the natural history and outcome of 24 infants with isolated CAVB diagnosed in utero, review the literature, and assess the risk factors that could predict outcome. METHODS: This was a retrospective multicenter study of 24 patients with isolated CAVB diagnosed in utero. RESULTS: CAVB was detected at a mean gestational age (GA) of 24.7 +/- 5.1 weeks. Ten fetuses initially presented with complete heart block. Low heart rate or incomplete heart block was the first documentation of bradyarrhythmia in the other 14 fetuses. In 11 of them, CAVB developed during pregnancy after a median time of 3 (range 1-16) weeks. Fetal hydrops developed in 10 of 24 (42%) fetuses at a mean GA of 27.6 +/- 5.1 weeks. Hydropic fetuses showed lower heart rates during pregnancy (47 +/- 10 bpm) than non-hydropic fetuses (57 +/- 10 bpm). There were three intrauterine deaths; all were hydropic and female. Nine viable females and 12 males were born at a mean GA of 37.1 +/- 6.1 weeks with an average birth weight of 3097 +/- 852 g. Fifteen CAVB patients required pacemaker (PM) intervention, 10 of them immediately after birth. Dilated cardiomyopathy (DCM) developed in three infants of whom two died of congestive heart failure, shortly after the diagnosis was made; one is still alive. Mortality before or after birth was 21%, and was associated with heart rates below 50 bpm and development of fetal hydrops. Poor outcome, defined as death, PM implantation, or development of DCM, occurred in 83% of cases and was associated with heart rates below 60 bpm during pregnancy. CONCLUSIONS: Isolated CAVB diagnosed in utero is associated with high morbidity and mortality. Patients who develop fetal hydrops show lower heart rates during pregnancy than patients who do not. A fetal heart rate below 50 bpm and development of fetal hydrops is associated with increased mortality. Rates below 60 bpm are associated with PM requirement and/or DCM.

Biological activity of neosergeolide and isobrucein B (and two semi-synthetic derivatives) isolated from the Amazonian medicinal plant Picrolemma sprucei (Simaroubaceae)

In the present study, in vitro techniques were used to investigate a range of biological activities of known natural quassinoids isobrucein B (1) and neosergeolide (2), known semi-synthetic derivative 1,12-diacetylisobrucein B (3), and a new semi-synthetic derivative, 12-acetylneosergeolide (4). These compounds were evaluated for general toxicity toward the brine shrimp species Artemia franciscana, cytotoxicity toward human tumour cells, larvicidal activity toward the dengue fever mosquito vector Aedes aegypti, haemolytic activity in mouse erythrocytes and antimalarial activity against the human malaria parasite Plasmodium falciparum. Compounds 1 and 2 exhibited the greatest cytotoxicity against all the tumor cells tested (IC50 = 5-27 µg/L) and against multidrug-resistant P. falciparum K1 strain (IC50 = 1.0-4.0 g/L) and 3 was only cytotoxic toward the leukaemia HL-60 strain (IC50 = 11.8 µg/L). Quassinoids 1 and 2 (LC50 = 3.2-4.4 mg/L) displayed greater lethality than derivative 4 (LC50 = 75.0 mg/L) toward A. aegypti larvae, while derivative 3 was inactive. These results suggest a novel application for these natural quassinoids as larvicides. The toxicity toward A. franciscana could be correlated with the activity in several biological models, a finding that is in agreement with the literature. Importantly, none of the studied compounds exhibited in vitro haemolytic activity, suggesting specificity of the observed cytotoxic effects. This study reveals the biological potential of quassinoids 1 and 2 and to a lesser extent their semi-synthetic derivatives for their in vitro antimalarial and cytotoxic activities.

Population structure and diversity of the pathogenic fungus Aspergillus fumigatus isolated from different sources and geographic origins

Fifty-five clinical and environmental Aspergillus fumigatus isolates from Mexico, Argentina, France and Peru were analyzed to determine their genetic variability, reproductive system and level of differentiation using amplified fragment length polymorphism markers. The level of genetic variability was assessed by measuring the percentage of polymorphic loci, number of effective alleles, expected heterozygocity and by performing an association index test (I A). The degree of genetic differentiation and variation was determined using analysis of molecular variance at three levels. Using the paired genetic distances, a dendrogram was built to detect the genetic relationship among alleles. Finally, a network of haplotypes was constructed to determine the geographic relationship among them. The results indicate that the clinical isolates have greater genetic variability than the environmental isolates. The I A of the clinical and environmental isolates suggests a recombining population structure. The genetic differentiation among isolates and the dendrogram suggest that the groups of isolates are different. The network of haplotypes demonstrates that the majority of the isolates are grouped according to geographic origin.

Pulsed-field gel electrophoresis, virulence determinants and antimicrobial susceptibility profiles of type Ia group B streptococci isolated from humans in Brazil

Group B streptococci (GBS) infections occur worldwide. Although serotyping has been used for epidemiologic purposes, this does not accurately characterize enough members of a genetically heterogeneous bacterial population. The aims of this work were to evaluate the genetic diversity of 45 type Ia GBS strains isolated in Brazil by pulsed-field gel electrophoresis as well as to evaluate antimicrobial susceptibility profiles and identify virulence genes. Twenty-four strains were assigned to cluster A. All strains under study contained the hylB and scpB genes. The bca gene was detected in only 10 strains and none of the streptococci carried the bac gene. Thirty-nine strains were resistant to tetracycline.

Mitochondrial dysfunction and mitophagy activation in blood mononuclear cells of fibromyalgia patients: implications in the pathogenesis of the disease.

Introduction. Fibromyalgia is a chronic pain syndrome with unknown etiology. Recent studies have shown some evidence demonstrating that oxidative stress may have a role in the pathophysiology of fibromyalgia. However, it is still not clear whether oxidative stress is the cause or the effect of the abnormalities documented in fibromyalgia. Furthermore, the role of mitochondria in the redox imbalance reported in fibromyalgia also is controversial. We undertook this study to investigate the role of mitochondrial dysfunction, oxidative stress, and mitophagy in fibromyalgia. Methods. We studied 20 patients (2 male, 18 female patients) from the database of the Sevillian Fibromyalgia Association and 10 healthy controls. We evaluated mitochondrial function in blood mononuclear cells from fibromyalgia patients measuring, coenzyme Q10 levels with high-performance liquid chromatography (HPLC), and mitochondrial membrane potential with flow cytometry. Oxidative stress was determined by measuring mitochondrial superoxide production with MitoSOX™ and lipid peroxidation in blood mononuclear cells and plasma from fibromyalgia patients. Autophagy activation was evaluated by quantifying the fluorescence intensity of LysoTracker™ Red staining of blood mononuclear cells. Mitophagy was confirmed by measuring citrate synthase activity and electron microscopy examination of blood mononuclear cells. Results. We found reduced levels of coenzyme Q10, decreased mitochondrial membrane potential, increased levels of mitochondrial superoxide in blood mononuclear cells, and increased levels of lipid peroxidation in both blood mononuclear cells and plasma from fibromyalgia patients. Mitochondrial dysfunction was also associated with increased expression of autophagic genes and the elimination of dysfunctional mitochondria with mitophagy. Conclusions. These findings may support the role of oxidative stress and mitophagy in the pathophysiology of fibromyalgia.

Molluscicidal activity of Hammada scoparia (Pomel) Iljin leaf extracts and the principal alkaloids isolated from them against Galba truncatula

The molluscicidal activity of Hammada scoparia leaf extracts and the principal alkaloids isolated from them (carnegine and N-methylisosalsoline) were tested against the mollusc gastropod, Galba truncatula, the intermediate host of Fasciola hepatica in Tunisia. The results indicated that the molluscicidal activity was correlated with the presence of alkaloids. A significant molluscicidal value, according to the World Health Organization, was found with the methanol extract (LC50 = 28.93 ppm). Further fractionation of the methanolic extract led to the isolation of two principal alkaloids: carnegine and N-methylisosalsoline. These alkaloids are isoquinolines that have not previously been characterised for their molluscicidal activity. The N-methylisosalsoline possesses the highest molluscicidal activity (LC50 = 0.47 μM against G. truncatula).

Tracing lineage by phenotypic and genotypic markers in Salmonella enterica subsp. enterica serovar 1,4,[5],12:i:- and Salmonella Typhimurium isolated in state of São Paulo, Brazil

Fifty-three Salmonella 1,4,[5],12:i:- and 45 Salmonella Typhimurium strains were characterised using phage typing, plasmid profiles and pulsed-field gel electrophoresis (PFGE) for comparison. The majority of the strains were subdivided into definitive type (DT) 41 (22.6%) and DT 193 (18%) and the 60-MDa plasmid was detected in 94.3% and 84.4% of strains, respectively. Genetic diversity was observed among all strains and 90% presented a > 70% similarity through PFGE analysis. These results suggest a close relationship between Salmonella 1,4,[5],12:i:- and Salmonella Typhimurium at the serotype level.

Immune and inflammatory responses to Leishmania amazonensis isolated from different clinical forms of human leishmaniasis in CBA mice

Leishmania amazonensis causes different diseases depending on the host and parasitic virulence factors. In this study, CBA mice were infected with L. amazonensis isolates from patients with localized (Ba125), diffuse cutaneous (Ba276) or visceral leishmaniasis (Ba109). Mice infected with Ba125 and Ba276 progressed rapidly and lesions displayed an infiltrate rich in parasitized macrophages and were necrotic and ulcerated. Ba109 induced smaller lesions and a mixed inflammatory infiltrate without necrosis or ulceration. Ba109 induced an insidious disease with lower parasite load in CBA mice, similar to human disease. Levels of IFN-γ, IL-4 and IL-10 did not differ among the groups. Because all groups were unable to control the infection, expression of IL-4 associated with low production of IFN-γ in the early phase of infection may account for susceptibility, but others factors may contribute to the differences observed in inflammatory responses and infection progression. Evaluation of some parasitic virulence factors revealed that Ba276 exhibits higher ecto-ADPase and 5'-nucleotidase activities compared to the Ba109 and Ba125 strains. Both Ba276 and Ba125 had higher arginase activity in comparison to Ba109. Finally, these data suggest that the differences in enzyme activities among parasites can account for differences in host inflammatory responses and infection progression.

Activation of GPER-1 estradiol receptor downregulates production of testosterone in isolated rat Leydig cells and adult human testis.

PURPOSE: Estradiol (E2) modulates testicular functions including steroidogenesis, but the mechanisms of E2 signaling in human testis are poorly understood. GPER-1 (GPR30), a G protein-coupled membrane receptor, mediates rapid genomic and non-genomic response to estrogens. The aim of this study was to evaluate GPER-1 expression in the testis, and its role in estradiol dependent regulation of steroidogenesis in isolated rat Leydig cells and human testis. MATERIALS AND METHODS: Isolated Leydig cells (LC) from adult rats and human testicular tissue were used in this study. Expression and localization studies of GPER-1 were performed with qRT-PCR, immunofluorescence, immunohistochemistry and Western Blot. Luteinizing Hormone (LH) -stimulated, isolated LC were incubated with estradiol, G-1 (GPER-1-selective agonist), and estrogen receptor antagonist ICI 182,780. Testosterone production was measured with radioimmunoassay. LC viability after incubation with G-1 was measured using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay. RESULTS: GPER-1 mRNA is abundantly expressed in rat LC and human testis. Co-localization experiments showed high expression levels of GPER-1 protein in LC. E2-dependent activation of GPER-1 lowers testosterone production in isolated rats LCs and in human testis, with statistically and clinically significant drops in testosterone production by 20-30% as compared to estradiol-naïve LC. The exposure to G-1 does not affect viability of isolated LCs. CONCLUSIONS: Our results indicate that activation of GPER-1 lowers testosterone levels in the rat and human testis. The expression of GPER-1 in human testis, which lack ERα, makes it an exciting target for developing new agents affecting testosterone production in men.

Prevalence and Clinical Features of Isolated Clinical Hypertension and Dipping Profile in a Large Cohort of Untreated Hypertensive Subjects

Aim: To examine the prevalence and clinical features of isolated clinical hypertension (ICH) and the dipping patterns in a large cohort of untreated hypertensive subjects form the Spanish ABPM registry

Molecular and immunological characterization of gluten proteins isolated from oat cultivars that differ in toxicity for celiac disease.

A strict gluten-free diet (GFD) is the only currently available therapeutic treatment for patients with celiac disease (CD). Traditionally, treatment with a GFD has excluded wheat, barley and rye, while the presence of oats is a subject of debate. The most-recent research indicates that some cultivars of oats can be a safe part of a GFD. In order to elucidate the toxicity of the prolamins from oat varieties with low, medium, and high CD toxicity, the avenin genes of these varieties were cloned and sequenced, and their expression quantified throughout the grain development. At the protein level, we have accomplished an exhaustive characterization and quantification of avenins by RP-HPLC and an analysis of immunogenicity of peptides present in prolamins of different oat cultivars. Avenin sequences were classified into three different groups, which have homology with S-rich prolamins of Triticeae. Avenin proteins presented a lower proline content than that of wheat gliadin; this may contribute to the low toxicity shown by oat avenins. The expression of avenin genes throughout the development stages has shown a pattern similar to that of prolamins of wheat and barley. RP-HPLC chromatograms showed protein peaks in the alcohol-soluble and reduced-soluble fractions. Therefore, oat grains had both monomeric and polymeric avenins, termed in this paper gliadin- and glutenin-like avenins. We found a direct correlation between the immunogenicity of the different oat varieties and the presence of the specific peptides with a higher/lower potential immunotoxicity. The specific peptides from the oat variety with the highest toxicity have shown a higher potential immunotoxicity. These results suggest that there is wide range of variation of potential immunotoxicity of oat cultivars that could be due to differences in the degree of immunogenicity in their sequences.

Biological, biochemical and molecular features of Trypanosoma cruzi strains isolated from patients infected through oral transmission during a 2005 outbreak in the state of Santa Catarina, Brazil: its correspondence with the new T. cruzi Taxonomy Consensus (2009)

We examined strains of Trypanosoma cruzi isolated from patients with acute Chagas disease that had been acquired by oral transmission in the state of Santa Catarina, Brazil (2005) and two isolates that had been obtained from a marsupial (Didelphis aurita) and a vector (Triatoma tibiamaculata). These strains were characterised through their biological behaviour and isoenzymic profiles and genotyped according to the new Taxonomy Consensus (2009) based on the discrete typing unities, that is, T. cruzi genotypes I-VI. All strains exhibited the biological behaviour of biodeme type II. In six isolates, late peaks of parasitaemia, beyond the 20th day, suggested a double infection with biodemes II + III. Isoenzymes revealed Z2 or mixed Z1 and Z2 profiles. Genotyping was performed using three polymorphic genes (cytochrome oxidase II, spliced leader intergenic region and 24Sα rRNA) and the restriction fragment length polymorphism of the kDNA minicircles. Based on these markers, all but four isolates were characterised as T. cruzi II genotypes. Four mixed populations were identified: SC90, SC93 and SC97 (T. cruzi I + T. cruzi II) and SC95 (T. cruzi I + T. cruzi VI). Comparison of the results obtained by different methods was essential for the correct identification of the mixed populations and major lineages involved indicating that characterisation by different methods can provide new insights into the relationship between phenotypic and genotypic aspects of parasite behaviour.

High-density lipoprotein prevents SAA-induced production of TNF-α in THP-1 monocytic cells and peripheral blood mononuclear cells

In this study, we evaluated whether human serum and lipoproteins, especially high-density lipoprotein (HDL), affected serum amyloid A (SAA)-induced cytokine release. We verified the effects of SAA on THP-1 cells in serum-free medium compared to medium containing human serum or lipoprotein-deficient serum. SAA-induced tumour necrosis factor-alpha (TNF-α) production was higher in the medium containing lipoprotein-deficient serum than in the medium containing normal human serum. The addition of HDL inhibited the SAA-induced TNF-α release in a dose-dependent manner. This inhibitory effect was specific for HDL and was not affected by low-density lipoprotein or very low-density lipoprotein. In human peripheral blood mononuclear cells, the inhibitory effect of HDL on TNF-α production induced by SAA was less pronounced. However, this effect was significant when HDL was added to lipoprotein-deficient medium. In addition, a similar inhibitory effect was observed for interleukin-1 beta release. These findings confirm the important role of HDL and support our previous hypothesis that HDL inhibits the effects of SAA during SAA transport in the bloodstream. Moreover, the HDL-induced reduction in the proinflammatory activity of SAA emphasizes the involvement of SAA in diseases, such as atherosclerosis, that are characterized by low levels of HDL.