Haplotype analysis of the internationally distributed BRCA1 c.3331_3334delCAAG founder mutation reveals a common ancestral origin in Iberia.

BACKGROUND: The BRCA1 c.3331_3334delCAAG founder mutation has been reported in hereditary breast and ovarian cancer families from multiple Hispanic groups. We aimed to evaluate BRCA1 c.3331_3334delCAAG haplotype diversity in cases of European, African, and Latin American ancestry. METHODS: BC mutation carrier cases from Colombia (n = 32), Spain (n = 13), Portugal (n = 2), Chile (n = 10), Africa (n = 1), and Brazil (n = 2) were genotyped with the genome-wide single nucleotide polymorphism (SNP) arrays to evaluate haplotype diversity around BRCA1 c.3331_3334delCAAG. Additional Portuguese (n = 13) and Brazilian (n = 18) BC mutation carriers were genotyped for 15 informative SNPs surrounding BRCA1. Data were phased using SHAPEIT2, and identical by descent regions were determined using BEAGLE and GERMLINE. DMLE+ was used to date the mutation in Colombia and Iberia. RESULTS: The haplotype reconstruction revealed a shared 264.4-kb region among carriers from all six countries. The estimated mutation age was ~ 100 generations in Iberia and that it was introduced to South America early during the European colonization period. CONCLUSIONS: Our results suggest that this mutation originated in Iberia and later introduced to Colombia and South America at the time of Spanish colonization during the early 1500s. We also found that the Colombian mutation carriers had higher European ancestry, at the BRCA1 gene harboring chromosome 17, than controls, which further supported the European origin of the mutation. Understanding founder mutations in diverse populations has implications in implementing cost-effective, ancestry-informed screening.

TLR2 deficiency by compromising p19 (IL-23) expression limits Th 17 cell responses to Mycobacterium tuberculosis.

CD4(+) T(h)1 cells producing IFN-γ are of extreme importance in controlling infections by Mycobacterium tuberculosis both in mice and in men. In addition to IFN-γ-producing T cells, IL-17-producing T cells (T(h)17) have been observed during mycobacterial infections. Nevertheless, their contribution for the host immune response to mycobacteria as well as the signals triggering M. tuberculosis -specific T(h)17 cell differentiation and maintenance are not fully understood. We show that signaling via Toll-like receptor (TLR) 2 has a major impact on the regulation of p19 (IL-23) expression in response to M. tuberculosis and therefore on the establishment of T(h)17 cell responses to M. tuberculosis infection. Diminished T(h)17 responses in the lung of M. tuberculosis -infected TLR2-deficient animals were not caused by defective cell differentiation in the draining lymph node (LN) but rather by reduced maintenance at the site of infection. Consistent with the decreased numbers of T(h)17 cells in the lungs of infected TLR2-deficient animals, we observed reduced expression of CXCL9, CXCL10 and CXCL11, chemokines involved in recall responses to M. tuberculosis. Our data provides insights into the TLR2 role in infection with M. tuberculosis, with implications in pathophysiology of the disease and vaccine design.

IFN-gamma-dependent activation of macrophages during experimental infections by Mycobacterium ulcerans is impaired by the toxin mycolactone.

Buruli ulcer, caused by Mycobacterium ulcerans infections, is a necrotizing skin disease whose pathogenesis is associated with the exotoxin mycolactone. Despite the relevance of this emergent disease, little is known on the immune response against the pathogen. Following the recent demonstration of an intramacrophage growth phase for M. ulcerans, we investigated the biological relevance of IFN-gamma and the antimycobacterial mechanisms activated by this cytokine in M. ulcerans-infected macrophages. Three M. ulcerans strains were tested: 5114 (mutant mycolactone-negative, avirulent strain); 94-1327 (intermediate virulence); and 98-912 (high virulence). We show in this study that IFN-gamma is expressed in mouse-infected tissues and that IFN-gamma-deficient mice display increased susceptibility to infection with strains 5114 and, to a lesser extent, 94-1327, but not with the highly virulent strain. Accordingly, IFN-gamma-activated cultured macrophages controlled the proliferation of the avirulent and the intermediate virulent strains. Addition of mycolactone purified from strain 98-912 to cultures of IFN-gamma-activated macrophages infected with the mycolactone-negative strain led to a dose-dependent inhibition of the IFN-gamma-induced protective mechanisms, involving phagosome maturation/acidification and increased NO production, therefore resulting in increased bacterial burdens. Our findings suggest that the protection mediated by IFN-gamma in M. ulcerans-infected macrophages is impaired by the local buildup of mycolactone.

Higher Fecal Short-Chain Fatty Acid Levels Are Associated with Gut Microbiome Dysbiosis, Obesity, Hypertension and Cardiometabolic Disease Risk Factors.

Fiber fermentation by gut microbiota yields short-chain fatty acids (SCFAs) that are either absorbed by the gut or excreted in feces. Studies are conflicting as to whether SCFAs are beneficial or detrimental to cardiometabolic health, and how gut microbiota associated with SCFAs is unclear. In this study of 441 community-dwelling adults, we examined associations of fecal SCFAs, gut microbiota diversity and composition, gut permeability, and cardiometabolic outcomes, including obesity and hypertension. We assessed fecal microbiota by 16S rRNA gene sequencing, and SCFA concentrations by gas chromatography/mass spectrometry. Fecal SCFA concentrations were inversely associated with microbiota diversity, and 70 unique microbial taxa were differentially associated with at least one SCFA (acetate, butyrate or propionate). Higher SCFA concentrations were associated with a measure of gut permeability, markers of metabolic dysregulation, obesity and hypertension. Microbial diversity showed association with these outcomes in the opposite direction. Associations were significant after adjusting for measured confounders. In conclusion, higher SCFA excretion was associated with evidence of gut dysbiosis, gut permeability, excess adiposity, and cardiometabolic risk factors. Studies assessing both fecal and circulating SCFAs are needed to test the hypothesis that the association of higher fecal SCFAs with obesity and cardiometabolic dysregulation is due to less efficient SCFA absorption.

Uncommon patterns of antinuclear antibodies recognizing mitotic spindle apparatus antigens and clinical associations.

Antinuclear antibodies (ANA) are key biomarkers in the evaluation of rheumatic diseases. The prevalence and clinical significance of uncommon or rare patterns, particularly those directed at the mitotic spindle apparatus (MSA), are not well understood. We aimed to investigate the prevalence and clinical significance of anti-MSA patterns in a Colombian population.During 2013 and 2014, 113,491 consecutive determinations of ANA were studied for the presence of uncommon patterns. Clinical and laboratory data of anti-MSA positive patients were retrospectively collected and analyzed.Of the 113,491 patients tested, 60,501 (53%) were positive for ANA, of which 834 (1.3%) were positive for uncommon/rare patterns of ANA (anti-MSA in 592 cases). Of these 592 cases, complete data were available in 329 patients, of whom 116 had an established diagnosis. Anti-MSA antibodies were the only ANA positive test in 81% patients. At least one fine reactivity was identified in 19/116 (16.3%) of ANA-positive patients, of which anti-Ro was the most prevalent (18/116, 15.5%).The most frequent patterns were nuclear mitotic apparatus (NuMA) (56%) and MSA-2 (25%). The NuMA pattern had the highest ANA titers: mean 320 (range 80-2560) and behaved as monospecific antibodies. The most frequent systemic autoimmune diseases were Sjögren syndrome (SS) (18.1%), rheumatoid arthritis (RA) (13.8%), and systemic lupus erythematosus (SLE) (11%). Undifferentiated connective tissue disease (UCTD) was associated with the centrosome (P < .001), NuMA (P < .02) and MSA-2 (P < .45) patterns. Chronic idiopathic urticaria (CIU) was associated with the NuMA pattern (P < .02) and sensorineural hearing loss (SNHL) was associated with the MSA-2 (P < .001), centrosome (P < .68) and CENP-F (P < .38) patterns, previously unreported findings. Malignancies were found in 8 patients (50% were papillary thyroid cancer).In a large cohort of ANA determinations, uncommon patterns were found in around 1% of cases. The most frequent anti-MSA patterns found were NuMA and MSA-2. More than 50% of patients with anti-MSA had an associated CTD, mainly SS, RA and SLE, and anti-MSA behaved as monospecific antibodies. Other entities of presumed autoimmune origin, like CIU and SNHL, might be associated with these patterns.

Gut microbiota is associated with obesity and cardiometabolic disease in a population in the midst of Westernization.

Westernization and its accompanying epidemiological transitions are associated with changes in gut microbiota. While the extremes of this lifestyle spectrum have been compared (hunter-gatherers, industrialized countries), populations undergoing such shifts have received little attention. To fill the gap of knowledge about the microbiome evolution following broad lifestyle changes and the emergence of disease-associated dysbiosis, we performed a cross-sectional study in which we characterized the microbiota of 441 Colombian adults through 16S rRNA gene sequencing and determined its relationship with demographic, health-related and dietary parameters. We showed that in the gut microbiota of this cohort thrive taxa proper of both hunter-gatherers (Prevotella, Treponema) and citizens of industrialized countries (Bacteroides, Bifidobacterium, Barnesiella); the relative abundances of these taxa differed from those in Western and non-Western populations. We also showed that the Colombian gut microbiota is composed of five consortia of co-abundant microorganisms that are differentially associated with lifestyle, obesity and cardiometabolic disease, and highlighted metabolic pathways that might explain associations between microbiota and host health. Our results give insights into the evolution of the gut microbiota, and underscore the importance of this community to human health. Promoting the growth of specific microbial consortia could help ameliorating physiological conditions associated with Western lifestyles.

Metformin Is Associated With Higher Relative Abundance of Mucin-Degrading Akkermansia muciniphila and Several Short-Chain Fatty Acid-Producing Microbiota in the Gut.

OBJECTIVE: Recent studies suggest the beneficial effects of metformin on glucose metabolism may be microbially mediated. We examined the association of type 2 diabetes, metformin, and gut microbiota in community-dwelling Colombian adults. On the basis of previous research, we hypothesized that metformin is associated with higher levels of short-chain fatty acid (SCFA)-producing and mucin-degrading microbiota. RESEARCH DESIGN AND METHODS: Participants were selected from a larger cohort of 459 participants. The present analyses focus on the 28 participants diagnosed with diabetes-14 taking metformin- and the 84 participants without diabetes who were matched (3-to-1) to participants with diabetes by sex, age, and BMI. We measured demographic information, anthropometry, and blood biochemical parameters and collected fecal samples from which we performed 16S rRNA gene sequencing to analyze the composition and structure of the gut microbiota. RESULTS: We found an association between diabetes and gut microbiota that was modified by metformin use. Compared with participants without diabetes, participants with diabetes taking metformin had higher relative abundance of Akkermansia muciniphila, a microbiota known for mucin degradation, and several gut microbiota known for production of SCFAs, including Butyrivibrio, Bifidobacterium bifidum, Megasphaera, and an operational taxonomic unit of Prevotella. In contrast, compared with participants without diabetes, participants with diabetes not taking metformin had higher relative abundance of Clostridiaceae 02d06 and a distinct operational taxonomic unit of Prevotella and a lower abundance of Enterococcus casseliflavus. CONCLUSIONS: Our results support the hypothesis that metformin shifts gut microbiota composition through the enrichment of mucin-degrading A. muciniphila as well as several SCFA-producing microbiota. Future studies are needed to determine if these shifts mediate metformin's glycemic and anti-inflammatory properties.

BCG vaccination-induced long-lasting control of Mycobacterium tuberculosis correlates with the accumulation of a novel population of CD4⁺IL-17⁺TNF⁺IL-2⁺ T cells.

Mycobacterium bovis Bacille Calmette-Guerin (BCG) is the only vaccine in use to prevent Mycobacterium tuberculosis (Mtb) infection. Here we analyzed the protective efficacy of BCG against Mtb challenges 21 or 120 days after vaccination. Only after 120 days post-vaccination were mice able to efficiently induce early Mtb growth arrest and maintain long-lasting control of Mtb. This protection correlated with the accumulation of CD4(+) T cells expressing IL-17(+)TNF(+)IL-2(+). In contrast, mice challenged with Mtb 21 days after BCG vaccination exhibited only a mild and transient protection, associated with the accumulation of CD4(+) T cells that were mostly IFN-γ(+)TNF(+) and to a lesser extent IFN-γ(+)TNF(+)IL-2(+). These data suggest that the memory response generated by BCG vaccination is functionally distinct depending upon the temporal proximity to BCG vaccination. Understanding how these responses are generated and maintained is critical for the development of novel vaccination strategies against tuberculosis.

Changes in GDPase/UDPase enzymatic activity in response to oxidative stress in four Candida species.

The terminal processing of proteins and lipids occurs in the Golgi apparatus and involves the transport of sugar nucleotides into the Golgi lumen by specific carriers and the accumulation of nucleoside diphosphates (NDPs) as a result of oligosaccharide-protein glycosyltransferase activity. NDPs are converted into the corresponding nucleoside monophosphates (NMPs) by nucleoside diphosphatases (NDPases), thus relieving inhibition of sugar transferases. In addition, NMPs are then exchanged for equimolecular amounts of cytosolic sugar nucleotides by antiport transport systems. NDPases, commonly GDPase and UDPase, thus play a critical role in glycoprotein maturation and may influence fungal pathogenesis, morphogenesis, and cell wall properties. Interest of this laboratory has recently focused on the effect of reactive oxygen species (ROS) on enzymes involved in detoxification of these oxidants and on the metabolism of biomolecules such as lipids, nucleic acids, and proteins in human pathogenic Candida species. We therefore consider it important to extend these studies to determine how GDPase and UDPase are affected after exposure of cells to oxidants such as menadione, a superoxide (O2 (•-))-generator, and H2O2. Results indicate that activity of both enzymes decrease in response to these agents suggesting that ROS may also affect other critical cell functions such as protein glycosylation.

Evaluación de una técnica de PCR en tiempo real para determinar colonización por Streptococcusagalactiae en mujeres gestantes de Medellín que consultan en Dinamica IPS / Evaluation of a real-time PCR technique to determine colonization by Streptococcus agalactiae in pregnant women of Medellín who consult in Dinamica IPS

Objetivo: Evaluar una técnica de PCR en tiempo real para determinar colonización por Streptococcus agalactiae en mujeres gestantes de Medellín. Materiales Y Métodos: Se realizó un estudio descriptivo prospectivo, en 150 mujeres gestantes, seleccionadas de forma aleatoria, en una IPS en el periodo comprendido entre Enero-Julio 2016. Criterio de inclusión: Ser gestante entre la semana 35-37, declaración voluntaria de participación en el estudio y de exclusión el uso de antibióticos. A las pacientes, se les tomó muestra con hisopo de lintroito vaginal y de la región anal. Las muestras se procesaron para qPCR, cultivo en caldo selectivo con posterior siembra en agar sangre de carnero y medio cromogénico para S. agalactiae STRB (ChromIDTMStrepto,BioMérieuxSA.). Resultados: La prevalencia de colonización por S. agalactiae en las gestantes fue de 20,9% y 22,3% en agar sangre y agar cromogénico STRB respectivamente, mientras que mediante PCR en tiempo real la prevalencia fue de 36%. Al comparar la qPCR con la prueba de oro se encontró: sensibilidad 79,31% (ICdel95%:0,61-0,90), especificidad 75,45% (IC del 95%: 0,66-0,82), valor predictivo positivo 46% (IC del 95%:0,32-0,59) y negativo 93,2% (IC del 95%: 0,86-0,96). Discusión: Elempleo de la qPCR permitió aumentar la sensibilidad y la oportunidad diagnostica (Eltiempo requerido empleando elcultivo fue de 24-48 Horas y por qPCR 6 horas) ,impactando la reducción de riesgos de transmisión neonata lde S.agalactiae, lo cualpodría representar una Disminución en días de estancia y costos hospitalarios por una infección prevenible.

Materials and Methods: A prospective and descriptive study was conducted in 150 pregnant women, randomly selected, at an IPS between January and July 2016. Inclusion criteria: gestation period week 35-37, voluntary declaration of participation in the study. Exclusion criteria: the use of antibiotics. Samples were taken from the vaginal introitus and the anal region using a hyssop and processed for qPCR as well as the gold standard test [selective broth culture with subsequent culture in blood agar and chromogenic medium for S. agalactiae STRB (ChromIDTMStrepto, BioMérieux SA)]. Results: The prevalence of colonization by S. agalactiae in pregnant women was 20.9% and 22.3% in blood agar and chromogenic agar STRB respectively, where as using qPCR the prevalence was 36.0%. The time required using the culture was 24-48h compared to 6h for qPCR. Our data comparing qPCR with the gold standard test showed: sensitivity 79.31% (95% CI: 0.61-0.90), specificity 75.45% (95% CI: 0.66-0.82), positive predictive value 46.0% (95% CI: 0.32-0.59) and negative 93.2%(95% CI: 0.86-0.96). Discussion: The use of the qPCR increased the sensitivity and the diagnostic opportunity (4x to 8x faster using qPCR), which can lead to a decrease in the risk of neonatal transmission of S. agalactiae and result in a reduction in the length of hospital stay and costs induced by a preventable infection.

Mycobacterium tuberculosis Strains Are Differentially Recognized by TLRs with an Impact on the Immune Response.

Tuberculosis associates with a wide spectrum of disease outcomes. The Beijing (Bj) lineage of Mycobacterium tuberculosis (Mtb) is suggested to be more virulent than other Mtb lineages and prone to elicit non-protective immune responses. However, highly heterogeneous immune responses were reported upon infection of innate immune cells with Bj strains or stimulation with their glycolipids. Using both in vitro and in vivo mouse models of infection, we here report that the molecular mechanism for this heterogeneity may be related to distinct TLR activations. Among this Mtb lineage, we found strains that preferentially activate TLR2, and others that also activate TLR4. Recognition of Mtb strains by TLR4 resulted in a distinct cytokine profile in vitro and in vivo, with specific production of type I IFN. We also uncover a novel protective role for TLR4 activation in vivo. Thus, our findings contribute to the knowledge of the molecular basis underlying how host innate immune cells handle different Mtb strains, in particular the intricate host-pathogen interaction with strains of the Mtb Bj lineage.

Consenso médico de biopsia por aspiración con aguja fina de tiroides. reporte de citología tiroidea basado en el sistema de bethesda / Medical consensus of fine-needle aspiration biopsy of the thyroid. bethesda system for reporting thyroid cytopathology

En este artículo se presenta un consenso médico basado en el sistema de Bethesda del Instituto Nacionalde Cáncer (Estados Unidos) para el uso de la biopsia por aspiración con aguja fina en el manejo de nódulos tiroideos, realizado en conjunto con patólogos, radiólogos, endocrinólogos y otras especialidades médicas de Colombia, España, Chile, Venezuela, Estados Unidos y Panamá. En este trabajo se describen las indicaciones de la biopsia por aspiración con aguja fina de tiroides, requisitos previos, entrenamiento, acreditación, técnicas, terminología diagnóstica, pruebas complementarias y opciones de tratamiento. El objetivo del actual artículo es presentar ante la comunidad médica la clasificación de los reportes citológicos, el reporte de ecografía que propone usar el sistema de datos y el reporte de imágenes tiroideas (TIRADS, del inglés The Thyroid Imaging Reporting and Data System), el uso de la medición de tiroglobulina en biopsia por aspiración con aguja fina y técnicas de citología líquida;...

This article presents a medical consensus based on the Bethesda system of the National Cancer Institute (USA) for the use of fine needle aspiration biopsy in the management of thyroid nodules. This consensus was performed in conjunction with pathologists, radiologists, endocrinologists, and other medical specialties of Colombia, Spain, Chile, Venezuela, United States, and Panama. In this work was described the indications for fine needle aspiration biopsy of thyroid, prerequisites, training, accreditation, techniques, diagnostic terminology, additional tests and treatment options. The aim of this article is present to the medical community the classification of cytological report, ultrasound report using the data system, and the thyroid imaging reporting and data system (TIRADS); as well as, the use of thyroglobulin measurement in fine needle aspiration biopsy, and liquid-based cytology techniques...