978 resultados para Cytogenetic abnormalities
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The immunoloical profile of acquired immunodeficiency syndrome (AIDS) and chronic lymphadenopathy syndrome (CLAS) in 15 and 11 Brazilian patients, respectively, was studied. The AIDS patients showed reduced percentage of total T (CD3) and T-helper-inducer (CD4) lymphocytes, relative increase in numbers of T-suppressor-cytotoxic (CD8) cells and a marked inversion of T-helper-inducer/suppressor-cytotoxic (CD4/CD8) ratio. Lymphoproliferative responses to PHA, ConA, PPD and PWM were diminished. Hypergamaglobulinemia and high levels of circulating immune complexes were also found. The CLAS patients also showed important immunological alterations, but not so intense as those with AIDS. These data seems to be similar to those observed in other parts of the world.
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Splenic marginal zone lymphoma (SMZL) is a low grade B-cell non-Hodgkin's lymphoma. The molecular pathology of this entity remains poorly understood. To characterise this lymphoma at the molecular level, we performed an integrated analysis of 1) genome wide genetic copy number alterations 2) gene expression profiles and 3) epigenetic DNA methylation profiles.We have previously shown that SMZL is characterised by recurrent alterations of chromosomes 7q, 6q, 3q, 9q and 18; however, gene resolution oligonucleotide array comparative genomic hybridisation did not reveal evidence of cryptic amplification or deletion in these regions. The most frequently lost 7q32 region contains a cluster of miRNAs. qRT-PCR revealed that three of these (miR-182/96/183) show underexpression in SMZL, and miR-182 is somatically mutated in >20% of cases of SMZL, as well as in >20% of cases of follicular lymphoma, and between 5-15% of cases of chronic lymphocytic leukaemia, MALT-lymphoma and hairy cell leukaemia. We conclude that miR-182 is a strong candidate novel tumour suppressor miRNA in lymphoma.The overall gene expression signature of SMZL was found to be strongly distinct fromthose of other lymphomas. Functional analysis of gene expression data revealed SMZL to be characterised by abnormalities in B-cell receptor signalling (especially through the CD19/21-PI3K/AKT pathway) and apoptotic pathways. In addition, genes involved in the response to viral infection appeared upregulated. SMZL shows a unique epigenetic profile, but analysis of differentially methylated genes showed few with methylation related transcriptional deregulation, suggesting that DNA methylation abnormalities are not a critical component of the SMZL malignant phenotype.
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The aim of this study is to quantify the prevalence and types of rare chromosome abnormalities (RCAs) in Europe for 2000-2006 inclusive, and to describe prenatal diagnosis rates and pregnancy outcome. Data held by the European Surveillance of Congenital Anomalies database were analysed on all the cases from 16 population-based registries in 11 European countries diagnosed prenatally or before 1 year of age, and delivered between 2000 and 2006. Cases were all unbalanced chromosome abnormalities and included live births, fetal deaths from 20 weeks gestation and terminations of pregnancy for fetal anomaly. There were 10,323 cases with a chromosome abnormality, giving a total birth prevalence rate of 43.8/10,000 births. Of these, 7335 cases had trisomy 21,18 or 13, giving individual prevalence rates of 23.0, 5.9 and 2.3/10,000 births, respectively (53, 13 and 5% of all reported chromosome errors, respectively). In all, 473 cases (5%) had a sex chromosome trisomy, and 778 (8%) had 45,X, giving prevalence rates of 2.0 and 3.3/10,000 births, respectively. There were 1,737 RCA cases (17%), giving a prevalence of 7.4/10,000 births. These included triploidy, other trisomies, marker chromosomes, unbalanced translocations, deletions and duplications. There was a wide variation between the registers in both the overall prenatal diagnosis rate of RCA, an average of 65% (range 5-92%) and the prevalence of RCA (range 2.4-12.9/10,000 births). In all, 49% were liveborn. The data provide the prevalence of families currently requiring specialised genetic counselling services in the perinatal period for these conditions and, for some, long-term care.
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PURPOSE OF REVIEW: This article presents an overview of the common and various kinds of pupillary disorders that can be encountered in an outpatient setting. RECENT FINDINGS: The dorsal midbrain is a site where lesions may produce either an afferent or an efferent pupillary defect. The classic pupillary syndrome secondary to a dorsal midbrain lesion is bilateral light-near dissociation. Another recognized deficit is bilateral mydriasis. Recent reports have documented unilateral mydriasis, unilateral light-near dissociation, and a relative afferent pupillary defect without visual loss in association with lesions of the dorsal midbrain. These are rare syndromes. SUMMARY: Careful history and examination can often identify and localize the pupillary disorder, as well as guide appropriate evaluation.
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Myotonic dystrophy Type 1 (DM-1) is caused by abnormal expansion of a (CTG) repeat located in the DM protein kinase gene. Respiratory problems have long been recognized to be a major feature of this disorder. Because respiratory failure can be associated with dysfunction of phrenic nerves and diaphragm muscle, we examined the diaphragm and respiratory neural network in transgenic mice carrying the human genomic DM-1 region with expanded repeats of more than 300 CTG, a valid model of the human disease. Morphologic and morphometric analyses revealed distal denervation of diaphragm neuromuscular junctions in DM-1 transgenic mice indicated by a decrease in the size and shape complexity of end-plates and a reduction in the concentration of acetyl choline receptors on the postsynaptic membrane. More importantly, there was a significant reduction in numbers of unmyelinated, but not of myelinated, fibers in DM-1 phrenic nerves; no morphologic alternations of the nerves or loss of neuronal cells were detected in medullary respiratory centers or cervical phrenic motor neurons. Because neuromuscular junctions are involved in action potential transmission and the afferent phrenic unmyelinated fibers control the inspiratory activity, our results suggest that the respiratory impairment associated with DM-1 may be partially due to pathologic alterations in neuromuscular junctions and phrenic nerves.
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Human and chimpanzee genomes are 98.8% identical within comparable sequences. However, they differ structurally in nine pericentric inversions, one fusion that originated human chromosome 2, and content and localization of heterochromatin and lineage-specific segmental duplications. The possible functional consequences of these cytogenetic and structural differences are not fully understood and their possible involvement in speciation remains unclear. We show that subtelomeric regions-regions that have a species-specific organization, are more divergent in sequence, and are enriched in genes and recombination hotspots-are significantly enriched for species-specific histone modifications that decorate transcription start sites in different tissues in both human and chimpanzee. The human lineage-specific chromosome 2 fusion point and ancestral centromere locus as well as chromosome 1 and 18 pericentric inversion breakpoints showed enrichment of human-specific H3K4me3 peaks in the prefrontal cortex. Our results reveal an association between plastic regions and potential novel regulatory elements.
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This article tries to demonstrate by new pathological findings (with the use of immunohistochemical technique and confocal laser microscopy) that chronic chagasic cardiomyopathy is a result of multiple factors involving myocarditis, immunodepression, severe fibrosis and microvessels dilatation and that all of these alterations are probably directly related with the presence of Trypanosoma cruzi parasites in the host associated with inadequate immunological response of the host.
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BACKGROUND: Second Harmonic Generation (SHG) microscopy recently appeared as an efficient optical imaging technique to probe unstained collagen-rich tissues like cornea. Moreover, corneal remodeling occurs in many diseases and precise characterization requires overcoming the limitations of conventional techniques. In this work, we focus on diabetes, which affects hundreds of million people worldwide and most often leads to diabetic retinopathy, with no early diagnostic tool. This study then aims to establish the potential of SHG microscopy for in situ detection and characterization of hyperglycemia-induced abnormalities in the Descemet's membrane, in the posterior cornea. METHODOLOGY/PRINCIPAL FINDINGS: We studied corneas from age-matched control and Goto-Kakizaki rats, a spontaneous model of type 2 diabetes, and corneas from human donors with type 2 diabetes and without any diabetes. SHG imaging was compared to confocal microscopy, to histology characterization using conventional staining and transmitted light microscopy and to transmission electron microscopy. SHG imaging revealed collagen deposits in the Descemet's membrane of unstained corneas in a unique way compared to these gold standard techniques in ophthalmology. It provided background-free images of the three-dimensional interwoven distribution of the collagen deposits, with improved contrast compared to confocal microscopy. It also provided structural capability in intact corneas because of its high specificity to fibrillar collagen, with substantially larger field of view than transmission electron microscopy. Moreover, in vivo SHG imaging was demonstrated in Goto-Kakizaki rats. CONCLUSIONS/SIGNIFICANCE: Our study shows unambiguously the high potential of SHG microscopy for three-dimensional characterization of structural abnormalities in unstained corneas. Furthermore, our demonstration of in vivo SHG imaging opens the way to long-term dynamical studies. This method should be easily generalized to other structural remodeling of the cornea and SHG microscopy should prove to be invaluable for in vivo corneal pathological studies.
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The involvement of the cerebellum in migraine pathophysiology is not well understood. We used a biparametric approach at high-field MRI (3 T) to assess the structural integrity of the cerebellum in 15 migraineurs with aura (MWA), 23 migraineurs without aura (MWoA), and 20 healthy controls (HC). High-resolution T1 relaxation maps were acquired together with magnetization transfer images in order to probe microstructural and myelin integrity. Clusterwise analysis was performed on T1 and magnetization transfer ratio (MTR) maps of the cerebellum of MWA, MWoA, and HC using an ANOVA and a non-parametric clusterwise permutation F test, with age and gender as covariates and correction for familywise error rate. In addition, mean MTR and T1 in frontal regions known to be highly connected to the cerebellum were computed. Clusterwise comparison among groups showed a cluster of lower MTR in the right Crus I of MWoA patients vs. HC and MWA subjects (p = 0.04). Univariate and bivariate analysis on T1 and MTR contrasts showed that MWoA patients had longer T1 and lower MTR in the right and left pars orbitalis compared to MWA (p < 0.01 and 0.05, respectively), but no differences were found with HC. Lower MTR and longer T1 point at a loss of macromolecules and/or micro-edema in Crus I and pars orbitalis in MWoA patients vs. HC and vs. MWA. The pathophysiological implications of these findings are discussed in light of recent literature.
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BACKGROUND: Within the frame of a twinning programme with Nicaragua, The La Mascota project, we evaluated in our study the contribution of cytogenetic characterization of acute lymphoblastic leukemia (ALL) as prognostic factor compared to clinical, morphological, and immunohistochemical parameters. METHODS: All patients with ALL treated at the only cancer pediatric hospital in Nicaragua during 2006 were studied prospectively. Diagnostic immunophenotyping was performed locally and bone marrow or blood samples were sent to the cytogenetic laboratory of Zurich for fluorescence in situ hybridization (FISH) analysis and G-banding. RESULTS: Sixty-six patients with ALL were evaluated. Their mean age at diagnosis was 7.3 years, 31.8% were >or=10 years. Thirty-four patients (51.5%) presented with hyperleucocytosis >or=50 x 10(9)/L, 45 (68.2%) had hepatosplenomegaly. Immunophenotypically 63/66 patients (95%) had a B-precursor, 2 (3%) a T- and 1 (1.5%) a B-mature ALL. FISH analysis demonstrated a TEL/AML1 fusion in 9/66 (14%), BCR/ABL fusion in 1 (1.5%), MLL rearrangement in 2 (3.1%), iAMP21 in 2 (3.1%), MYC rearrangement in 1 (1.5%), and high-hyperdiploidy in 16 (24%). All patients but two with TEL/AML1 fusion and high-hyperdiploidy were clinically and hematologically in the standard risk group whereas those with poor cytogenetic factors had clinical high-risk features and were treated intensively. CONCLUSIONS: Compared to Europe, the ALL population in Nicaragua is older, has a higher proportion of poor prognostic clinical and hematological features and receives more intensive treatment, while patients with TEL/AML1 translocations and high-hyperdiploidy are clinically in the standard risk group. Cytogenetics did not contribute as an additional prognostic factor in this setting.
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Schistosoma mansoni adult worms with genital anomalies isolated from Nectomys squamipes (Muridae: Sigmodontinae) were studied by confocal laser scanning microscopy under the reflected mode. One male without testicular lobes (testicular agenesia/anorchism) and two females, one with an atrophied ovary and another with 17 uterine eggs, were identified. The absence of testicular lobes occurred in a worm presenting otherwise normal male adult characteristics: tegument, tubercles and a gynaecophoric canal with spines. In both female specimens the digestive tube showed a vacuolated appearance, and the specimen with supernumerary uterine eggs exhibited a developing miracidium and an egg with a formed shell. The area of the ventral sucker was similar in both specimens however the tegument thickness, ovary and vitelline glands of the specimen with the atrophied ovary were smaller than those of the one with supernumerary eggs. These reported anomalies in the reproductive system call attention to the need to improve our understanding of genetic regulation and the possible role of environmental influences upon trematode development.
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The advent and application of high-resolution array-based comparative genome hybridization (array CGH) has led to the detection of large numbers of copy number variants (CNVs) in patients with developmental delay and/or multiple congenital anomalies as well as in healthy individuals. The notion that CNVs are also abundantly present in the normal population challenges the interpretation of the clinical significance of detected CNVs in patients. In this review we will illustrate a general clinical workflow based on our own experience that can be used in routine diagnostics for the interpretation of CNVs.
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Official certificates of stillbirth and infant death are analysed in the birth cohort of 1979-81. Congenital malformations account for approx. 40% of infant mortality. Cantonal differences in malformation rates are not explained by different incidence of such malformations only, but also by differences in lethality. Incidence of Anencephaly is examined in detail.
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BACKGROUND: The aim of this retrospective and monocentric study was to describe the magnetic resonance cholangiography (MRC) features of biliary abnormalities related to extrahepatic obstruction of the portal vein (EHOPV). METHODS: From September 2001 to May 2003, MRC was performed in 10 consecutive patients who had a portal thrombosis. RESULTS: Biliary ductal pathology was demonstrated via MRC in nine patients. It consisted of stenoses, ductal narrowing or irregularities involving the common bile duct for three patients with extrahepatic portal vein thrombosis discovered a mean of 1.5 years ago, or involving both right and left intrahepatic bile ducts and common bile duct for six patients with extrahepatic portal vein thrombosis discovered a mean of 16.2 years ago. Dilation of intrahepatic bile ducts was seen for seven patients, four of them having cholestasis. For three patients with symptomatic cholestasis, direct cholangiography (DC) was performed and showed the same findings as MRC which nevertheless overestimated the degree of bile duct stenosis. CONCLUSIONS: MRC seems to constitute an accurate tool to investigate noninvasively patients with portal biliopathy.
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The aim of the present study was to evaluate the prenatal detection of rare chromosomal autosomal abnormalities by ultrasound (US) examination. Data were obtained from 19 congenital malformation registries from 11 European countries, between 01/07/96 and 31/12/98. A total of 664,340 births were covered and 7,758 cases with congenital malformations were recorded. Rare autosomal abnormalities were diagnosed in 114 cases (6.6%) from a total of 1,738 chromosome abnormalities. There were a wide variety of autosomal abnormalities: the most common were deletions (33 cases), duplications (32 cases), trisomies of chromosomes 8, 9, 10, 14, 15, and 16 (23 cases), and unbalanced rearrangements (19 cases). Out of these cases, 45.6% were detected prenatally by US examination due to the presence of congenital anomaly. As for the types of chromosomal anomaly, unbalanced rearrangements and deletions were the most frequently detected by US. A high percentage of cases with balanced rearrangements were associated with severe congenital anomalies. The most frequent congenital anomalies detected by US were cystic hygroma (20.6%), central nervous system defects (17.6%), cardiac defects (13.2%), and diaphragm defects (10.3%). This large series offers useful information about prenatal diagnosis by US of congenital defects associated with rare autosomal abnormalities and it provides a valuable knowledge about outcome. Fetal anomalies detected by US that were associated with rare autosomal abnormalities were significantly more frequent than those associated with common chromosomal abnormalities (45.6 vs. 34.7%). This study indicates the need to increase the detection of congenital anomalies by US.