204 research outputs found
Hepatic complications in sickle cell disease
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
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
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
<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
Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas
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
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
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
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
Influence of socioeconomic factors on pregnancy outcome in women with structural heart disease
OBJECTIVE: Cardiac disease is the leading cause of indirect maternal mortality. The aim of this study was to analyse to what extent socioeconomic factors influence the outcome of pregnancy in women with heart disease. METHODS: The Registry of Pregnancy and Cardiac disease is a global prospective registry. For this analysis, countries that enrolled ≥10 patients were included. A combined cardiac endpoint included maternal cardiac death, arrhythmia requiring treatment, heart failure, thromboembolic event, aortic dissection, endocarditis, acute coronary syndrome, hospitalisation for cardiac reason or intervention. Associations between patient characteristics, country characteristics (income inequality expressed as Gini coefficient, health expenditure, schooling, gross domestic product, birth rate and hospital beds) and cardiac endpoints were checked in a three-level model (patient-centre-country). RESULTS: A total of 30 countries enrolled 2924 patients from 89 centres. At least one endpoint occurred in 645 women (22.1%). Maternal age, New York Heart Association classification and modified WHO risk classification were associated with the combined endpoint and explained 37% of variance in outcome. Gini coefficient and country-specific birth rate explained an additional 4%. There were large differences between the individual countries, but the need for multilevel modelling to account for these differences disappeared after adjustment for patient characteristics, Gini and country-specific birth rate. CONCLUSION: While there are definite interregional differences in pregnancy outcome in women with cardiac disease, these differences seem to be mainly driven by individual patient characteristics. Adjustment for country characteristics refined the results to a limited extent, but maternal condition seems to be the main determinant of outcome
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