A cell atlas of adult muscle precursors uncovers early events in fibre-type divergence in Drosophila.

In Drosophila, the wing disc-associated muscle precursor cells give rise to the fibrillar indirect flight muscles (IFM) and the tubular direct flight muscles (DFM). To understand early transcriptional events underlying this muscle diversification, we performed single-cell RNA-sequencing experiments and built a cell atlas of myoblasts associated with third instar larval wing disc. Our analysis identified distinct transcriptional signatures for IFM and DFM myoblasts that underlie the molecular basis of their divergence. The atlas further revealed various states of differentiation of myoblasts, thus illustrating previously unappreciated spatial and temporal heterogeneity among them. We identified and validated novel markers for both IFM and DFM myoblasts at various states of differentiation by immunofluorescence and genetic cell-tracing experiments. Finally, we performed a systematic genetic screen using a panel of markers from the reference cell atlas as an entry point and found a novel gene, Amalgam which is functionally important in muscle development. Our work provides a framework for leveraging scRNA-seq for gene discovery and details a strategy that can be applied to other scRNA-seq datasets.

Th1 immune response to H. pylori infection varies according to the age of the patients and influences the gastric inflammatory patterns.

To compare children and adults in respect to the effect of H. pylori infection on the gastric concentrations of cytokines linked to innate and Th1 immune response, as well as to investigate the changes in the gastric concentrations of the studied cytokines according to the age. We studied 245 children (142 H. pylori-negative and 103 H. pylori-positive) and 140 adults (40 H. pylori-negative and 100 H. pylori-positive). The gastric concentrations of cytokines representative of the innate and Th1 response were higher in the H. pylori-positive than in the -negative children and adults. The gastric concentrations of IL-1α and TNF-α were significantly higher, while those of IL-2, IL-12p70 and IFN-γ were lower in the infected children than in the infected adults. In the infected children, the gastric concentration of IL-1α, IL-2, IL-12p70 and IFN-γ increased, whereas in adults, the gastric concentrations of IFN-γ and IL-12p70 decreased with the aging. Increased gastric concentration of Th1 associated cytokines correlated with increased degree of gastritis that is the background lesion for the development of the H. pylori associated severe diseases. Concluding, Th1 response to H. pylori infection varies according to the age and seems to have determinant implication in the H. pylori infection outcomes.

The presence of Helicobacter pylori in the liver depends on the Th1, Th17 and Treg cytokine profile of the patient.

The hypothesis that Helicobactermight be a risk factor for human liver diseases has arisen after the detection of Helicobacter DNA in hepatic tissue of patients with hepatobiliary diseases. Nevertheless, no explanation that justifies the presence of the bacterium in the human liver has been proposed. We evaluated the presence of Helicobacterin the liver of patients with hepatic diseases of different aetiologies. We prospectively evaluated 147 patients (106 with primary hepatic diseases and 41 with hepatic metastatic tumours) and 20 liver donors as controls. Helicobacter species were investigated in the liver by culture and specific 16S rDNA nested-polymerase chain reaction followed by sequencing. Serum and hepatic levels of representative cytokines of T regulatory cell, T helper (Th)1 and Th17 cell lineages were determined using enzyme linked immunosorbent assay. The data were evaluated using logistic models. Detection of Helicobacter pylori DNA in the liver was independently associated with hepatitis B virus/hepatitis C virus, pancreatic carcinoma and a cytokine pattern characterised by high interleukin (IL)-10, low/absent interferon-γ and decreased IL-17A concentrations (p < 10(-3)). The bacterial DNA was never detected in the liver of patients with alcoholic cirrhosis and autoimmune hepatitis that are associated with Th1/Th17 polarisation. H. pylori may be observed in the liver of patients with certain hepatic and pancreatic diseases, but this might depend on the patient cytokine profile.

Effect of treatment of hepatic histopathology in children and adolescents with autoimmune hepatitis.

OBJECTIVE: To evaluate the effects of treatment on liver histopathology of children and adolescents diagnosed with autoimmune hepatitis. PATIENTS AND METHODS: Histopathological evaluation of liver biopsies performed at diagnosis or early during treatment, compared with biopsies after immunosuppressive treatment of 20 children and adolescents diagnosed with autoimmune hepatitis who presented clinical and biochemical remission for at least 24 months. Liver histopathology was assessed by 2 pathologists. Agreement between their interpretations was analyzed with kappa statistics. RESULTS: The age at diagnosis of the 20 patients varied from 1.7 years to 11.6 years (median = 6.6 years); 18 were females. The mean duration of clinical and biochemical remission, up to performance of liver biopsy, was 4.1 years. The mean interval between the initial and posttreatment biopsies was 4.6 years (range 2-9.7 years). Assessing the necroinflammatory activity, a mean reduction by 6.3 (observer 1) and 7.3 (observer 2) in the grading score was observed (P = 0.00000). When staging was assessed, a mean reduction by 1.8 (observers 1 and 2) in the score was observed after treatment (P = 0.00008), and there was no progression toward cirrhosis. No regression of cirrhosis was observed. CONCLUSIONS: On histopathological evaluation, the immunosuppressive treatment improved the fibrosis scores, with an arrest in its progression and no development into cirrhosis. Fibrosis control is mainly associated with regression of necroinflammatory activity, which is the main treatment component in autoimmune hepatitis.

[The dermatoscopy in the skin pathergy testing: case series in patients with suspected Behçet's Disease]. / Dermatoscopia no teste cutâneo da patergia: série de casos de pacientes com suspeita de Doença de Behçet.

Behçet's disease is a multisystemic disease consisting of a varying combination of ocular, mucocutaneous, neurologic, cardiovascular, gastrointestinal and other manifestations. Its diagnosis is based on clinical criteria, in which a positive pathergy test scores 1. A case series with 26 suspected patients is presented, and the skin pathergy test was performed in 23. The results were read in 48hours, and they were considered negative when without papule, and positive with a papule or pustule. Positive results were divided by papule size, and dermatoscopy was done to measure and observe its clinical aspects. After the readings, a biopsy was performed, with annotation of histopathological aspects. The test was negative in 2 (8.7%) and positive in 21 (91.3%) patients. The results and the literature review are presented.

Assessment of vascular invasion in gastric cancer: a comparative study.

AIM: To evaluate and compare detection of lymphatic and blood vessel invasion (LVI and BVI) by hematoxylin-eosin (HE) and immunohistochemistry (IHC) in gastric cancer specimens, and to correlate with lymph node status. METHODS: IHC using D2-40 (a lymphatic endothelial marker) and CD34 (a pan-endothelial marker) was performed to study LVI and BVI in surgical specimens from a consecutive series of 95 primary gastric cancer cases. The results of the IHC study were compared with the detection by HE using McNemar test and kappa index. The morphologic features of the tumors and the presence of LVI and BVI were related to the presence of lymph node metastasis. A χ(2) test was performed to obtain associations between LVI and BVI and other prognostic factors for gastric cancer. RESULTS: The detection rate of LVI was considerably higher than that of BVI. The IHC study identified eight false-positive cases and 13 false-negative cases for LVI, and 24 false-positive cases and 10 false-negative cases for BVI. The average Kappa value determined was moderate for LVI (κ = 0.50) and low for BVI (κ = 0.20). Both LVI and BVI were statistically associated with the presence of lymph node metastasis (HE: P = 0.001, P = 0.013, and IHC: P = 0.001, P = 0.019). The morphologic features associated with LVI were location of the tumor in the distal third of the stomach (P = 0.039), Borrmann's macroscopic type (P = 0.001), organ invasion (P = 0.03) and the depth of tumor invasion (P = 0.001). The presence of BVI was related only to the depth of tumor invasion (P = 0.003). CONCLUSION: The immunohistochemical identification of lymphatic and blood vessels is useful for increasing the accuracy of the diagnosis of vessel invasion and for predicting lymph node metastasis.

Iron status and Helicobacter pylori infection in symptomatic children: an international multi-centered study.

OBJECTIVE: Iron deficiency (ID) and iron deficiency anaemia (IDA) are global major public health problems, particularly in developing countries. Whilst an association between H. pylori infection and ID/IDA has been proposed in the literature, currently there is no consensus. We studied the effects of H. pylori infection on ID/IDA in a cohort of children undergoing upper gastrointestinal endoscopy for upper abdominal pain in two developing and one developed country. METHODS: In total 311 children (mean age 10.7±3.2 years) from Latin America--Belo Horizonte/Brazil (n = 125), Santiago/Chile (n = 105)--and London/UK (n = 81), were studied. Gastric and duodenal biopsies were obtained for evaluation of histology and H. pylori status and blood samples for parameters of ID/IDA. RESULTS: The prevalence of H. pylori infection was 27.7% being significantly higher (p<0.001) in Latin America (35%) than in UK (7%). Multiple linear regression models revealed H. pylori infection as a significant predictor of low ferritin and haemoglobin concentrations in children from Latin-America. A negative correlation was observed between MCV (r = -0.26; p = 0.01) and MCH (r = -0.27; p = 0.01) values and the degree of antral chronic inflammation, and between MCH and the degree of corpus chronic (r = -0.29, p = 0.008) and active (r = -0.27, p = 0.002) inflammation. CONCLUSIONS: This study demonstrates that H. pylori infection in children influences the serum ferritin and haemoglobin concentrations, markers of early depletion of iron stores and anaemia respectively.

Clinical course and prognostic factors of children with Burkitt's lymphoma in a developing country: the experience of a single centre in Brazil.

OBJECTIVE: Burkitt's lymphoma is the most common subtype of non-Hodgkin lymphoma in children. The aim of this study was to characterize the clinical course and prognostic factors of children and adolescents with Burkitt's lymphoma treated in the Hematology Unit of Hospital das Clínicas, Universidade Federal de Minas Gerais (UFMG). METHODS: A retrospective cohort study was made of 50 consecutive cases of children and adolescents aged 16 years or less with Burkitt's lymphoma admitted between January 1981 and December 2007. Prognostic factors associated with death were evaluated using the Kaplan-Meier method and compared by the two-tailed log-rank test. RESULTS: The median age at diagnosis was 4.7 years. Most patients had abdominal tumors (66.7%) and advanced disease (68.9%) at diagnosis. Thirty-eight patients (84.4%) achieved complete clinical remission and 33 (73.3%) were alive at the first remission. Twelve children (26.7%) died. The median follow-up was 35 months with the probability of overall survival being 73% (89.2% and 35.7% for patients with uric acid < 7 mg/dL and ≥ 7.0 mg/dL, respectively - p-value < 0.001). Uric acid was the only significant prognostic factor at diagnosis. CONCLUSION: Our findings confirm the favorable prognosis of children with Burkitt's lymphoma even when treated with intermediate doses of methotrexate (500 mg/m2). Survival was significantly lower for individuals with concentrations of uric acid > 7 mg/dL.

A regulatory instead of an IL-17 T response predominates in Helicobacter pylori-associated gastritis in children.

Th17 cells seem to have an important role in the efficacy of vaccines against Helicobacter pylori. Because children are a target group for human vaccination and Th17/T(reg) cells have intrinsically linked and antagonic commitments, we compared the gastric levels of Th17- and T(reg)-associated cytokines of children and adults. IL-6, IL-10 and TGF-ß1 levels and Foxp3(+) cell numbers were higher, but IL-1ß, IL-17A and IL-23 were lower in infected children than in infected adults. In conclusion T(reg) instead of Th17 cell response to H. pylori-infection predominates in children.

Langerhans cell histiocytosis: 37 cases in a single brazilian institution.

OBJECTIVES: To improve the level of 'definitive' diagnosis of Langerhans cell histiocytosis by immunohistochemical investigation of the CD1a surface antigen and to compare outcomes in respect to age, gender, stage of the disease, treatment response and level of diagnostic accuracy. METHODS: A retrospective study was carried out of 37 children and adolescents with possible Langerhans cell histiocytosis between 1988 and 2008. The diagnoses were revisited using immunohistochemical investigations for CD1a, S-100 and CD68 in an attempt to reach definitive diagnoses for all cases. RESULTS: Before the study, only 13 of 37 patients (35.1%) had a 'definitive' diagnosis; by the end of the study, this number rose to 25 patients (67.6%). All reviewed cases were positive for the CD1a antigen. Overall survival was 88.5%. Multisystem disease (Stage 2; n=19) and absence of response at the 6th week of therapy (n=5) were associated to significantly lower overall survival (p-value = 0.04 and 0.0001, respectively). All deaths occurred in patients with multisystem disease and organ dysfunction at diagnosis. Other potential prognostic factors were not significant. Reactivation episodes occurred in 75% of the patients with multisystem disease. Diabetes insipidus was the most common sequel (21.6%). CONCLUSION: The level of diagnostic accuracy was increased through immunohistochemistry. The overall survival rate was similar to international multicentric studies. Multisystem disease and absence of response at six weeks of treatment were the most important unfavorable prognostic factors. The frequency of reactivation for patients with multisystem disease was higher than described in the literature, probably because maintenance chemotherapy was used only in two cases.

Música underground y resistencia cultural en las periferias de Rio de Janeiro-un estudio de caso / Underground music and cultural resistance in the peripheries of Rio de Janeiro-a case study / Música underground e resistência cultural nas periferias do Rio de Janeiro-um estudo de caso

Este artículo corto discute las nociones de dominación y resistencia como aspectos de la trayectoria profesional de dos músicos residentes en la ciudad de São João de Meriti, Baixada Fluminense, una región proletarizada próxima à la ciudad de Río de Janeiro. Ellos hacen parte de un movimiento cultural underground llamado Hardcore, que és derivado de la cultura punk. Desarollado a partir de un estudio de caso, se analiza la relación entre la cultura y la juventud bajo la perspectiva de la dominación, y se levantan las posibilidades de ejercicio de resistencia en el ámbito cultural de ese contexto urbano. Los resultados presentados muestran que las resistencias recorren caminos de tensionamiento entre constituirse como una herramienta de tomada de consciencia de si mismo, de su lugar en el mundo y de apertura en relación a otras posibilidades de existencia, así como de recurso para producir una distancia o pureza en relación a otros modosde existir.

This short article discusses the notions of domination and cultural resistance as key aspects of the professional trajectory of two musicians who are part of an underground cultural movement called Hardcore, and live at São João de Meriti City, a poor and working class area near Rio de Janeiro. Based on a case study, the article discusses the relationship between youth and culture from the standpoint of cultural domination, and interrogates about eventual practices of cultural resistance in this urban context. The results presented show that the paths of resistance oscillate between the tension of either favouring the conscientization of one self, of one’s position in the world, and of one’s possibilities, or inducing the separation, the distance or purity between one’s own and others’ ways of living.

Este artigo curto discute as noções de dominação e resistência como aspectos do percurso profissional de dois músicos moradores da cidade de São João de Meriti, Baixada Fluminense, região metropolitana e proletária próxima à cidade do Rio de Janeiro. Eles fazem parte de um movimento cultural underground chamado Hardcore, oriundo da cultura punk. A partir de um estudo de caso, discute as relações entre cultura e juventude sob a perspectiva da dominação e levanta possibilidades de exercícios de resistência no âmbito cultural, neste contexto urbano. Os resultados apresentados mostram que as resistências percorrem caminhos de tensionamento entre constituir-se como ferramenta de tomada de consciência de si, de seu lugar no mundo e de abertura a outras possibilidades de existência, assim como de recurso para produzir uma distância ou pureza em relação a outros modos de existir.

[Accuracy of oncotic cytology for HPV infection diagnosis on the cervix uteri of HIV-infected women]. / Acuidade da citologia oncótica para o diagnóstico da infecção pelo HPV no colo uterino de mulheres portadoras do HIV.

PURPOSE: to verify the accuracy of uterine cervix cytology for HPV diagnosis, as compared to polymerase chain reaction (PCR) in samples of women with HIV. METHODS: 158 patients who had undergone a first collection of material from the uterine cervix with Ayre's spatula for PCR were included in the study. Then, another collection with Ayre's spatula and brush for oncotic cytology was performed. Only 109 slides were reviewed, as 49 of them had already been destructed for have being filed for over two years. RESULTS: the prevalence of HPV was 11% in the cytological exam and 69.7% in the PCR. Age varied from 20 to 61 years old, median 35 years. The HIV contagious route was heterosexual in 91.8% of the cases, and 79.1% of the patients had had from one to five sexual partners along their lives. The most frequent complaint was pelvic mass (5.1%), and 75.3% of the women had looked for the service for a routine medical appointment. The categorical variable comparison was done through contingency tables, using the chi2 test with Yates's correction to compare the ratios. The Fisher's test was used when one of the expected rates was lower than five. In the comparison of diagnostic tests, sensitivity, specificity and similarity ratios have been calculated. Among the 76 patients with HPV, detected by PCR, only 12 had the diagnosis confirmed by cytology (sensitivity=15.8%), which on the other hand did not present any false-positive results (specificity=100%). Concerning the HPV presence, the cytological prediction for positive results was 100% and 33.3% for negative, when both results were compared. Among the 12 patients with HPV positive cytology, four (33.3%) presented cervical intraepithelial neoplasia (OR=56; positive similarity ratio=positive infinity; negative similarity ratio=0.83). CONCLUSIONS: As the cytology specificity is quite high, it is possible to rely on the positive result, which means that a positive result will surely indicate the presence of HPV. The low sensitivity of cytology does not qualify it as a survey exam for HPV detection in this female group.

Hepatitis C, HCV genotypes and hepatic siderosis in patients with chronic renal failure on haemodialysis in Brazil.

BACKGROUND: The aim of this study was to investigate the HCV genotypes, hepatic siderosis, inflammatory activity and fibrosis of the liver in patients with chronic renal failure (CRF) on haemodialysis in Brazil. METHODS: A cohort of 72 CRF patients was compared with a group of 65 candidates for blood donation (CBD). For the subjects selected, who tested positive for anti-HCV antibodies and were HCV-PCR positive, a protocol with epidemiological, clinical and laboratory information was completed. An ultrasound-guided liver biopsy was performed and histological analysis of liver fragments was carried out. The presence of HCV-RNA in plasma was established by nested-RT-PCR. The genotype was determined by Restriction Fragment Length Polymorphism (RFLP) analysis of the PCR product. RESULTS: HCV genotype 1 was predominant in both groups, but genotype 2 was the second most common amongst CRF patients, and there was a significant difference when compared with the CBD group (P=0.016). Regarding inflammation and fibrosis, no significant difference was observed in the histology of the liver between the study groups. Siderosis of the liver was more prevalent in the CRF group (P=0.000). Severe complications of liver biopsies were reported in 10 CRF patients (13.2%). CONCLUSIONS: Genotype 2 was observed more frequently in the haemodialysis group. No statistically significant difference was detected between the CRF and CBD groups with regard to both inflammatory response and liver fibrosis. Hepatic siderosis has been attributed to excessive iron administration. As percutaneous liver biopsy resulted in severe complications, we suggest that other procedures of evaluating liver damage in CRF patients should be looked at thoughtfully.