180 research outputs found

    Hepatic complications in sickle cell disease

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    Patients with sickle cell disease may present acute or chronic hepatopathy. The acute syndrome is characterized by right upper quadrant abdominal pain and jaundice. The differential diagnoses include acute sickle hepatic crises, hepatic sequestration, sickle cell intrahepatic cholestasis, cholecystitis, choledocholithiasis and acute viral hepatitis. These alterations can be differentiated by a careful history, liver function tests and hepatobiliary imaging studies. The specific treatment must be promptly initiated. Red blood cell transfusion is essential for the treatment of the clinical syndromes caused by the sickling process such as hepatic sequestration and sickle cell intrahepatic cholestasis. Chronic liver disease is frequently caused by chronic hemolysis and multiple transfusions. In an attempt to prevent, early diagnosis and treatment of chronic liver disease, sickle cell disease patients must be routinely submitted to liver function tests, serologic tests for hepatitis B and C, serum ferritin levels and abdominal ultrasound. Liver biopsy may be indicated in patients with virus hepatitis and in patients with persistent and accentuated alterations in liver function tests, out of acute sickle cell hepatic crises.Doentes falciformes podem apresentar alterações hepáticas agudas ou crônicas. As agudas são caracterizadas por dor no quadrante superior direito e icterícia. O diagnóstico diferencial inclui crise aguda de falcização hepática, seqüestro hepático, colestase intra-hepática, colelitíase, coledocolitíase, colecistite e hepatite viral aguda. Estas complicações devem ser diagnosticadas precocemente, através de história clínica, testes de função hepática e exames radiológicos, e o tratamento deve ser prontamente iniciado. Transfusão sangüínea é essencial para o tratamento das manifestações agudas causadas pelo processo de vaso-oclusão, como seqüestro hepático e colestase intra-hepática. As alterações hepáticas crônicas são freqüentemente causadas pela hemólise crônica e múltiplas transfusões. Para prevenção, diagnóstico precoce e orientação terapêutica da alteração hepática crônica, os doentes falciformes devem ser submetidos a exames de rotina: testes de função hepática, sorologia para hepatite B e C, dosagem sérica de ferritina e ultra-sonografia de abdômen. A biópsia hepática deve ser realizada em pacientes com hepatite viral e em pacientes com alterações hepáticas crônicas acentuadas e persistentes, afora das manifestações agudas.29930

    3D scaffolds to model the hematopoietic stem cell niche: applications and perspectives

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    Hematopoietic stem cells (HSC) are responsible for the production of blood and immune cells during life. HSC fate decisions are dependent on signals from specialized microenvironments in the bone marrow, termed niches. The HSC niche is a tridimensional environment that comprises cellular, chemical, and physical elements. Introductorily, we will revise the current knowledge of some relevant elements of the niche. Despite the importance of the niche in HSC function, most experimental approaches to study human HSCs use bidimensional models. Probably, this contributes to the failure in translating many in vitro findings into a clinical setting. Recreating the complexity of the bone marrow microenvironment in vitro would provide a powerful tool to achieve in vitro production of HSCs for transplantation, develop more effective therapies for hematologic malignancies and provide deeper insight into the HSC niche. We previously demonstrated that an optimized decellularization method can preserve with striking detail the ECM architecture of the bone marrow niche and support HSC culture. We will discuss the potential of this decellularized scaffold as HSC niche model. Besides decellularized scaffolds, several other methods have been reported to mimic some characteristics of the HSC niche. In this review, we will examine these models and their applications, advantages, and limitations143FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2013/17227-

    G-6-PD deficiency in a Brazilian community: an investigation involving epidemiological genetics and molecular techniques

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    This paper reports on a study of the G-6-PD deficiency in Bragança Paulista, São Paulo State, Brazil. A total of 4,621 male blood donors were investigated over a 36-month period. Of these, 80 had the G-6-PD deficiency. Molecular analysis was performed on 70 unrelated G-6-PD deficients through DNA amplification followed by digestion with restriction enzymes and single strand conformation polymorphism analysis (SSCP). In 98.6%, the G-6-PD A- (202 G->A) mutation was observed through digestion of exon 4 with Nla III. The presence of an uncommon mutation in exon 9 was also observed through SSCP. No case of the Mediterranean variant was observed. These results indicate that the A- (202G->A) variant, almost exclusive, was introduced into the community not only by individuals of African origin, but also by European immigrants, mainly Italian, Spanish, and Portuguese. The Italian contribution in terms of the G-6-PD Mediterranean variant was smaller than its contribution to beta thalassemia, probably due to the Northern Italian origin of these immigrants.Este trabalho teve por objetivo estudar a deficiência de G-6-PD em uma comunidade do interior do Estado de São Paulo (Bragança Paulista). Durante 36 meses foram selecionados 4.621 doadores de sangue do sexo masculino, detectando-se 80 deficientes em G-6-PD. A análise molecular foi realizada em 70 deficientes não consangüíneos mediante a amplificação de DNA por PCR seguida de digestão por enzimas de restrição e análise de polimorfismo de conformação em hélice simples (SSCP). Em 98,6% dos casos, foi identificada a mutação G-6-PD A- (202 G->A), por digestão do exon 4 com Nla III. Verificou-se a presença de mutação mais rara no exon 9, por SSCP. Não foi constatado caso da variante Mediterrânea. Tais resultados mostraram que a variante A- (202 G->A), quase que exclusiva, foi introduzida na comunidade não apenas por descendentes de africanos, como também pelos imigrantes italianos, espanhóis e portugueses. A contribuição italiana em termos da variante Mediterrânea de G-6-PD foi menor do que a sua participação em termos de talassemia beta, provavelmente devido à origem no Norte da Itália.33534

    Identification of protein-coding and non-coding RNA expression profiles in CD34+ and in stromal cells in refractory anemia with ringed sideroblasts

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    <p>Abstract</p> <p>Background</p> <p>Myelodysplastic syndromes (MDS) are a group of clonal hematological disorders characterized by ineffective hematopoiesis with morphological evidence of marrow cell dysplasia resulting in peripheral blood cytopenia. Microarray technology has permitted a refined high-throughput mapping of the transcriptional activity in the human genome. Non-coding RNAs (ncRNAs) transcribed from intronic regions of genes are involved in a number of processes related to post-transcriptional control of gene expression, and in the regulation of exon-skipping and intron retention. Characterization of ncRNAs in progenitor cells and stromal cells of MDS patients could be strategic for understanding gene expression regulation in this disease.</p> <p>Methods</p> <p>In this study, gene expression profiles of CD34<sup>+ </sup>cells of 4 patients with MDS of refractory anemia with ringed sideroblasts (RARS) subgroup and stromal cells of 3 patients with MDS-RARS were compared with healthy individuals using 44 k combined intron-exon oligoarrays, which included probes for exons of protein-coding genes, and for non-coding RNAs transcribed from intronic regions in either the sense or antisense strands. Real-time RT-PCR was performed to confirm the expression levels of selected transcripts.</p> <p>Results</p> <p>In CD34<sup>+ </sup>cells of MDS-RARS patients, 216 genes were significantly differentially expressed (q-value ≤ 0.01) in comparison to healthy individuals, of which 65 (30%) were non-coding transcripts. In stromal cells of MDS-RARS, 12 genes were significantly differentially expressed (q-value ≤ 0.05) in comparison to healthy individuals, of which 3 (25%) were non-coding transcripts.</p> <p>Conclusions</p> <p>These results demonstrated, for the first time, the differential ncRNA expression profile between MDS-RARS and healthy individuals, in CD34<sup>+ </sup>cells and stromal cells, suggesting that ncRNAs may play an important role during the development of myelodysplastic syndromes.</p

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

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    This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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    Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts

    Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

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    Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN

    Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

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    Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment
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