Real and complex integral closure, Lipschitz equisingularity and applications on square matrices

Recently the authors investigated the Lipschitz triviality of simple germs of matrices. In this work, we improve some previous results and we present an extension of an integral closure result for the real setting. These tools are applied to investigate classes of square matrices singularities classified by Bruce and Tari

A dysflagellar mutant of Leishmania (Viannia) braziliensis isolated from a cutaneous leishmaniasis patient

<p>Abstract</p> <p>Background</p> <p>Parasites of the <it>Leishmania </it>genus alternate between the flagellated extracellular promastigote stage and intracellular amastigotes. Here we report the characterization of a <it>Leishmania </it>isolate, obtained from a cutaneous leishmaniasis patient, which presents peculiar morphological features.</p> <p>Methods</p> <p>The parasite was cultured <it>in vitro </it>and characterized morphologically using optical and electron microscopy. Identification was performed based on monoclonal antibodies and internal ribosomal spacer typing. <it>In vitro </it>macrophage cultures, murine experimental models and sand fly infections were used to evaluate infectivity <it>in vitro </it>and <it>in vivo</it>.</p> <p>Results</p> <p>The isolate was identified as <it>Leishmania </it>(<it>Viannia</it>) <it>braziliensis</it>. In the atypical promastigotes grown in culture, a short flagellum surrounded or interrupted by a protuberance of disorganized material was observed. A normal axoneme was present close to the basal body but without elongation much further outside the flagellar pocket. A disorganized swelling at the precocious end of the axoneme coincided with the lack of a paraflagellar rod structure. The isolate was able to infect macrophages <it>in vitro</it>, induce lesions in BALB/c mice and infect <it>Lutzomyia longipalpis</it>.</p> <p>Conclusions</p> <p>Notwithstanding the lack of an extracellular flagellum, this isolate infects macrophages <it>in vitro </it>and produces lesions when inoculated into mice. Moreover, it is able to colonize phlebotomine sand flies. Considering the importance attributed to the flagellum in the successful infection and survival of <it>Leishmania </it>in the insect midgut and in the invasion of macrophages, these findings may bring new light into the infectious mechanisms of <it>L</it>. (<it>V</it>.) <it>braziliensis</it>.</p

Sensitive and specific serodiagnosis of Leishmania infantum infection in dogs by using peptides selected from hypothetical proteins identified by an immunoproteomic approach

In Brazil, the percentage of infected dogs living in areas where canine visceral leishmaniasis (CVL) is endemic ranges from 10 to 62%; however, the prevalence of infection in dogs is probably higher than figures reported from serological studies. In addition, problems with the occurrence of false-positive or false-negative results in the serodiagnosis of CVL have been reported. The present work analyzed the potential of synthetic peptides mapped from hypothetical proteins for improvement of the serodiagnosis of Leishmania infantum infection in dogs. From 26 identified leishmanial proteins, eight were selected, considering that no homologies between these proteins and others from trypanosomatide sequence databases were encountered. The sequences of these proteins were mapped to identify linear B-cell epitopes, and 17 peptides were synthesized and tested in enzyme-linked immunosorbent assays (ELISAs) for the serodiagnosis of L. infantum infection in dogs. Of these, three exhibited sensitivity and specificity values higher than 75% and 90%, respectively, to differentiate L. infantum-infected animals from Trypanosoma cruziinfected animals and healthy animals. Soluble Leishmania antigen (SLA) showed poor sensitivity (4%) and specificity (36%) to differentiate L. infantum-infected dogs from healthy and T. cruzi-infected dogs. Lastly, the three selected peptides were combined in different mixtures and higher sensitivity and specificity values were obtained, even when sera from T. cruzi-infected dogs were used. The study’s findings suggest that these three peptides can constitute a potential tool for more sensitive and specific serodiagnosis of L. infantum infection in dogsThis work was supported by grants from the Pró-Reitoria de Pesquisa from UFMG (Edital 07/2012), Instituto Nacional de Ciência e Tecnologia em Nano-biofarmacêutica (INCT-NANOBIOFAR, Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) (CBB-APQ-02364-08, CBB-APQ-00356-10, CBB-APQ-00496-11, and CBB-APQ-00819-12), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) (APQ-472090/2011-9), and the Instituto Nacional de Ciência e Tecnologia em Vacinas (INCT-V). E.A.F.C. and A.P.F. are CNPq grant recipients. M.A.C.-F. is a FAPEMIG/CAPES grant recipient. This study was supported in Spain, in part, by grants from the Ministerio de Ciencia e Innovación (FIS/PI1100095)

MACROECOLOGIA, BIOGEOGRAFIA E ÁREAS PRIORITÁRIAS PARA CONSERVAÇÃO NO CERRADO

revista vol 13 nº 3.indd Há consenso entre os cientistas de que a há atualmente uma “crise da biodiversidade”, resultado da constante e intensa perda de habitat natural causada pela expansão da ocupação. Como a biologia da conservação tem sido muitas vezes reconhecida como uma ciência da crise, ela deve fornecer informações capazes de mediar, de forma mais científica possível, as tomadas de decisão que são necessárias. Dentre estas, uma das mais importantes é indicar regiões prioritárias para a conservação, já que por motivos óbvios não é possível preservar todos os ecossistemas por inteiro. Nesse contexto, recentemente sugeriu-se que a aplicação de princípios, teorias e análises provenientes da biogeografia e da macroecologia seriam importantes na Biologia da Conservação, formalizando uma abordagem que tem sido denominada “Biogeografia da Conservação”. Assim, o objetivo deste artigo é discutir e revisar esses componentes da biogeografia da conservação, utilizando uma abordagem macroecológica para desenvolver e aplicar métodos de planejamento sistemático em conservação, utilizando o bioma Cerrado como um modelo de estudo. Foram discutidos inicialmente os padrões de riqueza e diversidade beta e, em um segundo momento, como esses padrões podem ser correlacionados à ocupação humana do Bioma. Essa relação é fundamental para subsidiar a aplicação de modelos de planejamento sistemático de conservação em escala regional (análises de insubstituibilidade, complementaridade e de lacunas). É preciso considerar também que há sérias falhas de conhecimento sobre os padrões de biodiversidade na região e que a escolha de grupos indicadores pode ser importante para minimizar problemas gerados pela falta de conhecimento. Assim, essa abordagem é interessante em um cenário de grandes incertezas (ausência de dados detalhados) e de rápida transformação da paisagem, possibilitando a otimização de estudos em grandes escalas e depois transferir os resultados para escalas espaciais mais locais e realmente relevantes para a conservação. Nessas regiões, podem ser realizados, em um segundo momento, estudos mais detalhados a fim de avaliar padrões de viabilidade populacional, fragmentação de habitat e regiões potenciais de manutenção da diversidade genética

Circulating adiponectin levels are lower in Latino versus non-Latino white patients at risk for cardiovascular disease, independent of adiposity measures

<p>Abstract</p> <p>Background</p> <p>Latinos in the United States have a higher prevalence of type 2 diabetes than non-Latino whites, even after controlling for adiposity. Decreased adiponectin is associated with insulin resistance and predicts T2DM, and therefore may mediate this ethnic difference. We compared total and high-molecular-weight (HMW) adiponectin in Latino versus white individuals, identified factors associated with adiponectin in each ethnic group, and measured the contribution of adiponectin to ethnic differences in insulin resistance.</p> <p>Methods</p> <p>We utilized cross-sectional data from subjects in the Latinos Using Cardio Health Actions to reduce Risk study. Participants were Latino (n = 119) and non-Latino white (n = 60) men and women with hypertension and at least one other risk factor for CVD (age 61 ± 10 yrs, 49% with T2DM), seen at an integrated community health and hospital system in Denver, Colorado. Total and HMW adiponectin was measured by RIA and ELISA respectively. Fasting glucose and insulin were used to calculate the homeostasis model insulin resistance index (HOMA-IR). Variables independently associated with adiponectin levels were identified by linear regression analyses. Adiponectin's contribution to ethnic differences in insulin resistance was assessed in multivariate linear regression models of Latino ethnicity, with logHOMA-IR as a dependent variable, adjusting for possible confounders including age, gender, adiposity, and renal function.</p> <p>Results</p> <p>Mean adiponectin levels were lower in Latino than white patients (beta estimates: -4.5 (-6.4, -2.5), p < 0.001 and -1.6 (-2.7, -0.5), p < 0.005 for total and HMW adiponectin), independent of age, gender, BMI/waist circumference, thiazolidinedione use, diabetes status, and renal function. An expected negative association between adiponectin and waist circumference was seen among women and non-Latino white men, but no relationship between these two variables was observed among Latino men. Ethnic differences in logHOMA-IR were no longer observed after controlling for adiponectin levels.</p> <p>Conclusions</p> <p>Among patients with CVD risk, total and HMW adiponectin is lower in Latinos, independent of adiposity and other known regulators of adiponectin. Ethnic differences in adiponectin regulation may exist and future research in this area is warranted. Adiponectin levels accounted for the observed variability in insulin resistance, suggesting a contribution of decreased adiponectin to insulin resistance in Latino populations.</p

Occurrence of genes of putative fibrinogen binding proteins and hemolysins, as well as of their phenotypic correlates in isolates of S. lugdunensis of different origins

<p>Abstract</p> <p>Background</p> <p><it>Staphylococcus lugdunensis </it>is an important human pathogen that causes potentially fatal endocarditis, osteomyelitis and skin and soft tissue infections similar to diseases caused by <it>Staphylococcus aureus</it>. Nevertheless, in contrast to <it>S. aureus</it>, data on pathogenicity factors of <it>S. lugdunensis </it>is scarce. Two adhesins, a fibrinogen and a von Willebrand factor binding protein, and a <it>S. lugdunensis </it>synergistic hemolysin (SLUSH) have been previously described. Moreover, the newly sequenced genome of <it>S. lugdunensis </it>revealed genes of other putative fibrinogen binding adhesins and hemolysins. The aim of this study was to gain more insight into the occurrence of genes likely coding for fibrinogen binding adhesins and hemolysins using clinical strains of <it>S. lugdunensis</it>.</p> <p>Findings</p> <p>Most of the putative adhesin genes and hemolysin genes investigated in this study were highly prevalent, except for the SLUSH gene cluster. In contrast to previous reports, binding to fibrinogen was detected in 29.3% of the <it>S. lugdunensis </it>strains. In most strains, hemolysis on blood agar plates was weak after 24 h and distinct after 48 h of incubation. The fibrinogen binding and hemolysis phenotypes were also independent of the type of clinical specimen, from which the isolates were obtained.</p> <p>Conclusion</p> <p>In this study we described a pyrrolidonyl arylamidase negative <it>S. lugdunensis </it>isolate. Our data indicate that a matrix-assisted laser desorption ionisation time-of-flight MS-based identification of <it>S. lugdunensis </it>or species-specific PCR's should be performed in favour of pyrrolidonyl arylamidase testing. In contrast to the high occurrence of putative fibrinogen binding protein genes, 29.3% of the <it>S. lugdunensis </it>strains bound to fibrinogen. Putative hemolysin genes were also prevalent in most of the <it>S. lugdunensis </it>strains, irrespective of their hemolysis activity on Columbia blood agar plates. Similar to a previous report, hemolysis after 48 h of incubation is also indicative for <it>S. lugdunensis</it>. The SLUSH gene cluster was detected in an estimated 50% of the strains, indicating that this locus is different or non-prevalent in many strains.</p

Liver Fibrosis and Metabolic Alterations in Adults With alpha-1-antitrypsin Deficiency Caused by the Pi*ZZ Mutation

BACKGROUND & AIMS: Alpha-1 antitrypsin deficiency (AATD) is among the most common genetic disorders. Severe AATD is caused by a homozygous mutation in the SERPINA1 gene that encodes the Glu342Lys substitution (called the Pi*Z mutation, Pi*ZZ genotype). Pi*ZZ carriers may develop lung and liver diseases. Mutation- associated lung disorders have been well studied, but less is known about the effects in liver. We assessed the liver disease burden and associated features in adults with this form of AATD. METHODS: We collected data from 554 Pi*ZZ adults (403 in an exploratory cohort, 151 in a confirmatory cohort), in 9 European countries, with AATD who were homozygous for the Pi*Z mutation, and 234 adults without the Pi*Z mutation (controls), all without pre-existing liver disease. We collected data on demographic parameters, comorbidities, lung- and liver-related health, and blood samples for laboratory analysis. Liver fibrosis was assessed non-invasively via the serum tests Aspartate Aminotransferase to Platelet Ratio Index and HepaScore and via transient elastography. Liver steatosis was determined via transient elastography-based controlled attenuation parameter. We performed histologic analyses of livers from transgenic mice that overexpress the AATD-associated Pi*Z variant. RESULTS: Serum levels of liver enzymes were significantly higher in Pi*ZZ carriers vs controls. Based on non-invasive tests for liver fibrosis, significant fibrosis was suspected in 20%–36% of Pi*ZZ carriers, whereas signs of advanced fibrosis were 9- to 20-fold more common in Pi*ZZ carriers compared to non-carriers. Male sex; age older than 50 years; increased levels of alanine aminotransferase, aspartate aminotransferase, or g-glutamyl transferase; and low numbers of platelets were associated with higher liver fibrosis burden. We did not find evidence for a relationship between lung function and liver fibrosis. Controlled attenuation parameter 280 dB/m, suggesting severe steatosis, was detected in 39% of Pi*ZZ carriers vs 31% of controls. Carriers of Pi*ZZ had lower serum concentrations of triglyceride and low- and very-lowdensity lipoprotein cholesterol than controls, suggesting impaired hepatic secretion of lipid. Livers from Pi*Zoverexpressing mice had steatosis and down-regulation of genes involved in lipid secretion. CONCLUSIONS: In studies of AATD adults with the Pi*ZZ mutation, and of Pi*Z-overexpressing mice, we found evidence of liver steatosisinfo:eu-repo/semantics/publishedVersio