Association between leukocyte telomere length and sex by quantile regression analysis

ABSTRACT Introduction: Telomere length (TL) is a biomarker of cellular proliferative history. In healthy individuals, leukocyte TL shortens with age and associates with the lifespan of men and women. However, most of studies had used linear regression models to address the association of the TL attrition, aging and sex. Methods: We evaluated the association between the TL, aging and sex in a cohort of 180 healthy subjects by quantile regression. The TL of nucleated blood cells was measured by fluorescent in situ hypridization (flow-FISH) in a cohort of 89 men, 81 women, and 10 umbilical cord samples. The results were validated by quantitative polymerase chain reaction (qPCR) and compared to a linear regression analysis. Results: By quantile regression, telomere dynamics slightly differed between sexes with aging: women had longer telomeres at birth and slower attrition rate than men until the sixth decade of life; after that, TL eroded faster and became shorter than that in men. These differences were not observed by linear regression analysis, as the overall telomere attrition rates in women and men were similar (42 pb per year, p < 0.0001 vs. 45 pb kb per year, p < 0.0001). Also, qPCR did not recapitulate flow-FISH findings, as the telomere dynamics by qPCR followed a linear model. Conclusion: The quantile regression analysis accurately reproduced a third-orderpolynomial TL attrition rate in both women and men, but it depended on the technique applied to measure TL. The Flow-FISH reproduced the expected telomere dynamics through life and, differently from the qPCR, was able to detect the subtle TL variations associated with sex and aging.

Young age and sex work are associated with HIV seroconversion among transgender women in São Paulo, Brazil

Background: Transgender women worldwide have among the highest prevalence of HIV and the lowest access to prevention among groups at risk. However, few longitudinal studies have directly measured HIV incidence and identified predictors of HIV acquisition among transgender women. Setting: São Paulo, Latin America's largest city. Methods: We conducted a longitudinal study among transgender women in São Paulo. Participants were recruited by a long-chain peer referral process from May 2017 to July 2019. Those age 18 years and older and HIV-negative at baseline were retested every 6 months up to 18 months. HIV incidence was calculated by dividing the number of seroconversions by the person-years (py) of follow-up; 95% confidence intervals (CI) were constructed assuming a Poisson distribution. Conditional maximum likelihood ratios assessed differences in HIV incidence by risk factors. Results: A racial/ethnically diverse sample of 545 transgender women were enrolled. In 485.5 py of follow-up, 13 seroconversions were observed yielding an incidence of 2.68 per 100 py (95% CI 1.43­4.58). HIV incidence was significantly higher among transgender women age 18 to 24 years (rate ratio 3.85, 95% CI 1.24­12.93) and among those who engaged in sex work in the preceding month (rate ratio 5.90, 95% CI 1.71­26.62). Conclusion: HIV transmission continues at a high rate among transgender women in Brazil. Factors such as young age, lower level of education, and limited employment opportunities may lead to dependence upon sex work which in turn increase HIV risk. Transgender-friendly prevention services, particularly programs delivering pre-exposure prophylaxis (PrEP) are urgently needed.

Familial pulmonary fibrosis: a heterogeneous spectrum of presentations / Fibrose pulmonar familiar: um espectro heterogêneo de apresentações

ABSTRACT Objective: To describe the clinical, functional, and radiological features of index cases of familial pulmonary fibrosis (FPF) in Brazil. Methods: We evaluated 35 patients with FPF - of whom 18 (51.4%) were women - with a median age of 66.0 years (range, 35.5-89.3 years). All of the patients completed a standardized questionnaire, as well as undergoing pulmonary function tests and HRCT of the chest. In 6 cases, lung tissue samples were obtained: from surgical biopsies in 5 cases; and from an autopsy in 1 case. Results: A history of smoking and a history of exposure to birds or mold were reported in 45.7% and 80.0% of the cases, respectively. Cough and marked dyspnea were reported by 62.8% and 48.6% of the patients, respectively. Fine crackles were detected in 91.4% of the patients. In 4 patients, the findings were suspicious for telomere disease. The median FVC and DLCO, as percentages of the predicted values, were 64.9% (range, 48.8-105.7%) and 38.9% (range, 16.0-60.0%), respectively. Nine patients had reduced DLCO despite having normal spirometry results. Regarding HRCT, patterns typical of usual interstitial pneumonia were found in 6 patients (17.1%). In 25 cases (71.5%), the HRCT features were consistent with a diagnosis other than idiopathic pulmonary fibrosis. In 11 cases (31.4%), the radiological patterns were uncharacteristic of interstitial lung disease. Of the six lung tissue samples analyzed, four showed interstitial pneumonia with bronchiolocentric accentuation, and, on the basis of the clinical and radiological data, the corresponding patients were diagnosed with hypersensitivity pneumonitis. Conclusions: Patients with FPF can present with a wide variety of clinical features. Most HRCT scans of these patients exhibit patterns not typical of usual interstitial pneumonia. The family history of fibrotic lung diseases should be investigated in all patients under suspicion, regardless of their age.

RESUMO Objetivo: Descrever as características clínicas, funcionais e radiológicas de um grupo de casos índice diagnosticados com fibrose pulmonar familiar (FPF) no Brasil. Métodos: Trinta e cinco pacientes com FPF (18 mulheres; 51,4%), com mediana de idade de 66,0 anos (variação: 35,5-89,3 anos), responderam a um questionário padronizado e foram submetidos a testes de função pulmonar e TCAR de tórax. Tecido pulmonar foi obtido para revisão em 6 casos: a partir de biópsias cirúrgicas em 5 e de autópsia em 1. Resultados: Antecedentes de tabagismo e de exposição a aves ou mofo foram referidos por 45,7% e 80,0% dos casos, respectivamente. Tosse e dispneia significante foram referidas por 62,8% e 48,6% dos pacientes, respectivamente. Estertores finos foram detectados em 91,4% dos indivíduos. Em 4 pacientes, os achados levantaram suspeitas de doença dos telômeros. As medianas da CVF e da DLCO foram, respectivamente, de 64,9% (variação: 48,8-105,7%) e 38,9% (variação: 16,0-60,0%) em porcentagem dos valores previstos. Apesar de espirometria normal, 9 pacientes exibiram DLCO reduzida. Em relação às TCAR, padrões típicos de pneumonia intersticial usual foram encontrados em 6 pacientes (17,1%). Em 25 casos (71,5%) os achados tomográficos foram mais consistentes com um diagnóstico de não relacionado a fibrose pulmonar idiopática. Em 11 pacientes (31,4%) o padrão radiológico foi incaracterístico para doença pulmonar intersticial. Das seis amostras de tecido pulmonar analisadas, quatro mostraram pneumonias intersticiais com acentuação bronquiolocêntrica e, em função de outros dados clínicos e radiológicos, pneumonite de hipersensibilidade foi diagnosticada. Conclusões: Pacientes com FPF podem apresentar características clínicas diversas. A maioria das TCAR desses pacientes exibe padrões não típicos de pneumonia intersticial usual. A pesquisa da história clínica de outros casos de pneumopatias fibrosantes na família deve ser feita em todos os pacientes em investigação, independentemente da idade.

THPO gene variants in patients with acquired aplastic anemia

ABSTRACT Background: Human aplastic anemia is a hematologic disease characterized by low peripheral blood cell counts associated with reduced numbers of hematopoietic stem and progenitor cells and a hypocellular bone marrow. Thrombopoietin (THPO) regulates megakaryocytes, but it also stimulates hematopoietic stem and progenitor cells. Biallelic mutations in the THPO gene have been reported in a family with recessive inherited aplastic anemia. Methods: This study screened 83 patients diagnosed with acquired aplastic anemia and 92 paired healthy controls for germline variants in the THPO gene using Sanger sequencing. Results: Three common single nucleotide polymorphisms were identified in patients and controls at comparable allele frequencies. There was no correlation between the single nucleotide polymorphism carrier status and platelet counts at diagnosis. Conclusion: The presence of THPO polymorphisms is comparable between patients with acquired aplastic anemia and healthy individuals.

Comparison of microRNA expression in high-count monoclonal B-cell lymphocytosis and Binet A chronic lymphocytic leukemia

Abstract Background Evidence suggests that monoclonal B-cell lymphocytosis precedes all chronic lymphocytic leukemia cases, although the molecular mechanisms responsible for disease progression are not understood. Aberrant miRNA expression may contribute to the pathogenesis of chronic lymphocytic leukemia. The objective of this study was to compare miRNA expression profiles of patients with Binet A chronic lymphocytic leukemia with those of subjects with high-count monoclonal B-cell lymphocytosis and healthy volunteers (controls). Methods Twenty-one chronic lymphocytic leukemia patients, 12 subjects with monoclonal B-cell lymphocytosis and ten healthy volunteers were enrolled in this study. Flow cytometry CD19+CD5+-based cell sorting was performed for the chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis groups and CD19+ cells were sorted to analyze the control group. The expressions of miRNAs (miR-15a, miR-16-1, miR-29b, miR-34a, miR-181a, miR-181b and miR-155) were determined by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Results Significant differences between the expressions in the chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis groups were restricted to the expression of miR-155, which was higher in the former group. A comparison between healthy controls and monoclonal B-cell lymphocytosis/chronic lymphocytic leukemia patients revealed higher miR-155 and miR-34a levels and lower miR-15a, miR-16-1, miR-181a and miR-181b in the latter group. Conclusions Our results show a progressive increase of miR-155 expression from controls to monoclonal B-cell lymphocytosis to chronic lymphocytic leukemia. The role of miR-155 in the development of overt chronic lymphocytic leukemia in individuals with monoclonal B-cell lymphocytosis must be further analyzed.

Telomere length correlates with disease severity and inflammation in sickle cell disease

ABSTRACT Background: Telomeres, the ends of linear chromosomes, shorten during mitotic cell division and erosion may be aggravated by inflammation or proliferative and oxidative stress. As the bone marrow is under hyperproliferative pressure in sickle cell disease and several tissues are submitted to chronic inflammation, this study sought to determine the telomere length of patients with sickle cell disease. Methods: The mean telomere length was measured in peripheral blood leukocytes by quantitative polymerase chain reaction. The age-adjusted telomere to single copy gene ratio was compared between 91 adult sickle cell disease patients and 188 controls. Results: Sickle cell disease patients had significantly shorter telomeres than the controls (p-value < 0.0001). Moreover, among sickle cell disease genotypes, Hb SS patients had significantly shorter telomeres compared to Hb SC and Hb Sβ patients (p-value < 0.0001). Patients on hydroxyurea also had shorter telomeres in comparison to those off the drug (p-value = 0.02). A positive correlation was observed between telomere length and hemoglobin level (r = 0.3; p-value = 0.004), whereas negative correlations were detected between telomere length and lymphocyte count (r = -0.3; p-value = 0.005) and interleukin-8 serum levels (r = -0.4; p-value = 0.02). Conclusions: The findings of this study indicate that telomeres are short in sickle cell disease patients and that telomere erosion directly correlates with disease genotype, inflammation markers, and the use of hydroxyurea.

ANALYSIS OF THE ERYTHROCYTE ALLOIMMUNIZATION PROFILE OF WOMEN WITH BREAST CANCER AT THE NATIONAL CANCER INSTITUTE / Análise do perfil de aloimunização eritrocitária de mulheres com câncer de mama do Instituto Nacional do Câncer

Objective: To describe the erythrocyte alloimmunization profile of women diagnosed with breast cancer at the National Cancer Institute, based on a comparison between routine antibody and irregular enzyme techniques. Methods: Experimental and prospective study with the application of human antiglobulin techniques and enzymatic technique in the search for irregular antibodies in pretransfusion tests of women with breast cancer treated at the hemotherapy service of Hospital do Câncer III, between June 2015 and May 2016. The variables were compared using Pearson's χ2 test or G-test, when indicated. Results: 429 cases were included. Of the total, 8 (1.86%) presented positive antibody screening test in routine human antiglobulin technique, while 32 (7.6%) were observed in the enzymatic technique. Significant differences were observed between alloimmunized and non-alloimmunized patients regarding ethnicity, RhD classification, transfusion history and alloantibody incidence time. Conclusion: The application of the enzymatic technique is proposed as a routine method in patients with breast cancer, as a way of avoiding transfusion reactions and ineffective phenotype transfusions.

Objetivos: Descrever o perfil de aloimunização eritrocitária de mulheres diagnosticadas com câncer de mama no Instituto Nacional do Câncer a partir da comparação entre as técnicas de pesquisa de anticorpo irregular utilizada em rotina e a técnica enzimática implantada. Métodos: Estudo experimental e prospectivo com aplicação das técnicas de antiglobulina humana e técnica enzimática na pesquisa de anticorpos irregulares de testes pré-transfusionais de mulheres com câncer de mama, atendidas no serviço de hemoterapia do Hospital do Câncer III, no período de junho de 2015 a maio de 2016. As variáveis foram comparadas pelo teste do χ2 de Pearson ou teste G, quando indicado. Resultados: Foram incluídos 429 casos. Do total, 8 (1,86%) apresentaram pesquisa de anticorpos irregulares positiva em técnica de antiglobulina humana na rotina, enquanto 32 (7,6%) foram observados na técnica enzimática. Foram observadas diferenças significantes entre aloimunizados e não aloimunizados quanto à etnia, classificação RhD, histórico transfusional e tempo de incidência de aloanticorpo. Conclusão: Propomos a aplicação da técnica enzimática como método de rotina em pacientes com câncer de mama, como forma de evitar reações transfusionais e transfusões ineficazes.

Splicing factor SF3B1 mutations and ring sideroblasts in myelodysplastic syndromes: a Brazilian cohort screening study

ABSTRACT Background: Myelodysplastic syndromes (MDS) comprise a group of malignant clonal hematologic disorders characterized by ineffective hematopoiesis and propensity for progression to acute myeloid leukemia. Acquired mutations in the gene encoding RNA splicing factor 3B subunit 1 (SF3B1) are highly associated with the MDS subtypes presenting ring sideroblasts, and represent a specific nosological entity. The effects of these mutations on clinical outcomes are diverse and contrasting. Methods: A cohort of 91 Brazilian MDS patients, including patients with ring sideroblasts in the bone marrow, were screened for mutations in the SF3B1 hotspots (exons 12-15) by direct Sanger sequencing. Results: SF3B1 heterozygous mutations were identified in six patients (7%), all of them with ring sideroblasts, thus confirming the association between SF3B1 mutations and myelodysplastic syndrome subtypes bearing this morphologic feature (frequency of 6/13, p-value < 0.0001). Conclusion: This is the first screening of SF3B1 mutations in a cohort of Brazilian myelodysplastic syndrome patients. Our findings confirm that mutations in this splicing gene correlate with bone marrow ringed sideroblasts.

Shwachman-Diamond syndrome: first molecular diagnosis in a Brazilian child

Herein the first molecular diagnosis of a Brazilian child with Shwachman-Diamond Syndrome is reported. A 6-year-old boy was diagnosed with cystic fibrosis at the age of 15 months due to recurrent respiratory infections, diarrhea and therapeutic response to pancreatic enzymes. Three sweat tests were negative. At the age of 5 years, he began to experience pain in the lower limbs, laxity of joints, lameness and frequent falls. A radiological study revealed metaphyseal chondrodysplasia. A complete blood cell count showed leukopenia (leukocytes: 3.1-3.5 x 103/µL), neutropenia (segmented neutrophils: 15-22%), but normal hemoglobin, hematocrit and platelet count. A molecular study revealed biallelic mutations in the Shwachman-Bodian-Diamond Syndrome gene (183-184TA-CT K62X in exon 2 and a 258+2T-C transition) confirming the diagnosis of Shwachman-Diamond Syndrome. A non-pathologic, silent nucleotide A to G transition at position 201 was also found in heterozygosis in the Shwachman-Bodian-Diamond Syndrome gene. This is the first report to describe a Brazilian child with molecular diagnosis of Shwachman-Diamond Syndrome, a rare autosomal recessive disorder characterized by exocrine pancreatic insufficiency, intermittent or persistent neutropenia and skeletal changes. Other characteristics include immune system, hepatic and cardiac changes and predisposition to leukemia. Recurrent bacterial, viral and fungal infections are common. The possibility of Shwachman-Diamond Syndrome should be kept in mind when investigating children with a diagnosis of cystic fibrosis and normal sweat tests.