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INTRODUCTION: Therapeutic measures have been successful in increasing survival rates and quality of life of HIV/AIDS-infected people. However, some people fail to respond to antiretroviral therapy (HAART) because of viral resistance-associated mutations. OBJECTIVE: To identify virus genotype and the presence of mutations that alter the susceptibility to HAART, and factors associated with the occurrence of these mutations. METHOD: A cross-sectional study was conducted on adults living with HIV attending a specialized outpatient clinic in southern Santa Catarina, Brazil. The participants were interviewed and had blood samples collected for analysis. Those with detectable viral load were genotyped. RESULTS: Out of the 629 patients recruited, 127 subjects were included due to having a detectable viral load. The most common mutations were M184V and K103N. HIV-1 subtype C was the most prevalent strain. Resistance to HAART was associated with modification in the treatment regimen (p <0.001). CONCLUSION: This study concluded that the circulating subtype virus was subtype C and that the mutations K103N and M184V were the most prevalent strains in southern Santa Catarina, Brazil.
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In this investigation, fecal specimens from children with diarrhea were collected from four community studies conducted between 1982 and 2019 in Belém, Brazilian Amazon. A total of 234 samples were tested by quantitative reverse transcription polymerase chain reaction (RT-qPCR) to detect infections by picornaviruses of the Enterovirus (EV), Parechovirus (HPeV), Cosavirus (HCoSV), Kobuvirus (Aichivirus - AiV) and Salivirus (SalV) genera. The positive samples were subjected to different amplification protocols of the VP1 region of the genome, such as nested PCR or snPCR, and were subsequently genotyped by sequencing VP1 and VP3 of the viral genome. Positivity was observed in 76.5% (179/234) of the samples tested using RT-qPCR for at least one virus, and co-infection was observed in 37.4% (67/179) of the cases. EV was detected in 50.8% (119/234), HPeV in 29.9% (70/234), HCoSV in 27.3% (64/234), and AiV/SalV in 2.1% (5/234) of the specimens tested by RT-qPCR. Using nested PCR and/or snPCR techniques, the positivity rates were 94.11% (112/119) for EV, 72.85% (51/70) for HPeV, and 20.31% (13/64) for HCoSV. It was not possible to amplify the samples that were positive for AiV/SalV. Sequencing revealed 67.2% (80/119) EV, 51.4% (36/70) HPeV, and 20.31% (13/64) HCoSV. Forty-five different types of EV were found among species A, B, and C; HCoSV identified five species, including a possible recombinant strain; all HPeV were identified as belonging to species A, in two samples a possible recombination involving three different strains was verified. This study demonstrated the high circulation and diversity of different types of picornaviruses in fecal samples, including those collected more than 30 years ago. This endorsed the evaluation of important points in the epidemiology of these viruses, such as the presence of co-infection and the possibility of knowing more about these agents, considering that some were recently described; therefore, their detection in older samples can provide more data about their ancestry.
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Coinfecção , Infecções por Enterovirus , Enterovirus , Infecções por Picornaviridae , Picornaviridae , Vírus , Criança , Humanos , Idoso , Picornaviridae/genética , Coinfecção/epidemiologia , Brasil/epidemiologia , Infecções por Enterovirus/epidemiologia , Enterovirus/genética , Diarreia/epidemiologiaRESUMO
INTRODUCTION: Human immunodeficiency virus (HIV) infection, the etiological agent of acquired immunodeficiency syndrome (AIDS), is a serious public health issue. Therapeutic measures have been successful in increasing the survival and improving the quality of life. However, some treatment-naive subjects living with HIV present resistance-associated mutations as a result of late diagnosis and/or mutant strain infections. The objective of this study was to identify the virus genotype and assess the antiretroviral resistance profile based on the results of HIV genotyping in treatment-naive subjects living with HIV, after six months of taking antiretroviral therapy. METHODS: This was a prospective cohort study on treatment-naive adults living with HIV attending a specialized outpatient clinic in southern Santa Catarina State, Brazil. The participants were interviewed and had blood samples drawn. The genotypic antiretroviral drug resistance profile was examined in patients with detectable viral loads. RESULTS: 65 treatment-naive subjects living with HIV were recruited for this study. After six months of taking antiretroviral therapy, resistance-associated mutations were observed in 3 (4.6%) subjects living with HIV. CONCLUSION: Subtype C was identified as the circulating subtype in southern Santa Catarina State, and L10V, K103N, A98G, and Y179D were the most common mutations found in treatment-naive subjects.
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Fármacos Anti-HIV , Infecções por HIV , Adulto , Humanos , Infecções por HIV/tratamento farmacológico , Estudos Prospectivos , Qualidade de Vida , Antirretrovirais/farmacologia , Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Mutação , Farmacorresistência Viral/genética , Genótipo , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêuticoRESUMO
Introduction: Fusarium is a very heterogeneous group of fungi, difficult to classify, with a wide range of living styles, acting as saprophytes, parasites of plants, or pathogens for humans and animals. Prevalence of clinical fusariosis and lack of effective treatments have increased the interest in the precise diagnosis, which implies a molecular characterization of Fusarium populations. Objective: We compared different genotyping markers in their assessment of the genetic variability and molecular identification of clinical isolates of Fusarium. Materials and methods: We evaluated the performance of the fingerprinting produced by two random primers: M13, which amplifies a minisatellite sequence, and (GACA)4, which corresponds to a simple repetitive DNA sequence. Using the Hunter Gaston Discriminatory Index (HGDI), an analysis of molecular variance (AMOVA), and a Mantel test, the resolution of these markers was compared to the reference sequencing-based and PCR genotyping methods. Results: The highest HGDI value was associated with the M13 marker followed by (GACA)4. AMOVA and the Mantel tests supported a strong correlation between the M13 classification and the reference method given by the partial sequencing of the transcription elongation factor 1-alpha (TEF1-α) and rDNA 28S. Conclusion: The strong correlation between the M13 classification and the sequencing-based reference together with its higher resolution demonstrates its adequacy for the characterization of Fusarium populations.
Introducción. Fusarium es un grupo heterogéneo de hongos, difícil de clasificar y con una amplia gama de estilos de vida, que actúa como saprófito, parásito de plantas o patógeno de humanos y animales. La prevalencia de la fusariosis clínica y la falta de tratamientos han incrementado el interés en su diagnóstico preciso, lo que conlleva la caracterización molecular de las poblaciones. Objetivo. Comparar marcadores de genotipificación en la evaluación de la variabilidad genética e identificación de aislamientos clínicos de Fusarium. Materiales y métodos. Se evaluó la huella genética producida por dos cebadores aleatorios: M13, que amplifica una secuencia minisatélite, y (GACA)4, que corresponde a una secuencia repetitiva de ADN. Utilizando el índice discriminatorio de Hunter Gaston (HGDI), el análisis de varianza molecular (AMOVA) y una prueba de Mantel, se comparó la resolución de estos marcadores con métodos de genotipificación basados en secuenciación y PCR. Resultados. El mayor HGDI se asoció con el marcador M13, seguido de (GACA)4. Las pruebas AMOVA y Mantel mostraron correlación entre las clasificaciones obtenidas con M13 y la referencia basada en la secuenciación parcial del factor de elongación de transcripción 1-alfa (TEF1-α) y el ADNr 28S. Conclusión. La fuerte correlación entre la clasificación obtenida con M13 y el método de referencia, así como su alta resolución, demuestran su idoneidad para la caracterización de poblaciones de Fusarium.
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Fusarium , Impressões Digitais de DNA , Bacteriófago M13 , Fusariose , Técnicas de Genotipagem , Elonguina , Genética PopulacionalRESUMO
In order to improve the diagnosis of giardiasis, fecal samples (high/medium/low concentration of cysts) were processed by the parasitological methods used in the routine: Faust, Lutz e Ritchie modified (replacement of formaldehyde by distilled water). The cysts were quantified; the DNA was extracted and amplified by semi-nested PCR (GDH gene). Fifteen clinical samples were analyzed to validate the study by PCR-RFLP. The results showed that the parasite was only detected and genotyped correctly when samples from children with high, medium, and low parasitic load, belonging to genotype AII, were processed by the modified Ritchie method, different from what was observed for the other methods used in laboratory routine (Faust and Lutz). The modified Ritchie method proved to be more suitable, recovering a greater number of cysts from samples, regardless of parasitic load, which reduces the chance of false negative results and has epidemiological repercussions since individuals with low parasite load are usually asymptomatic and the main disseminators of this infection.
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Técnicas de Genotipagem/métodos , Giardia lamblia/crescimento & desenvolvimento , Giardia lamblia/isolamento & purificação , Giardíase/parasitologia , Reação em Cadeia da Polimerase/métodos , Pré-Escolar , Fezes/parasitologia , Feminino , Genótipo , Giardia lamblia/genética , Giardíase/diagnóstico , Humanos , Lactente , Estágios do Ciclo de Vida , Masculino , Técnicas de Diagnóstico Molecular/métodos , Carga Parasitária , Proteínas de Protozoários/genéticaRESUMO
ABSTRACT Alpha-1 antitrypsin deficiency (AATD) is a rare genetic disorder caused by a mutation in the SERPINA1 gene, which encodes the protease inhibitor alpha-1 antitrypsin (AAT). Severe AATD predisposes individuals to COPD and liver disease. Early diagnosis is essential for implementing preventive measures and limiting the disease burden. Although national and international guidelines for the diagnosis and management of AATD have been available for 20 years, more than 85% of cases go undiagnosed and therefore untreated. In Brazil, reasons for the underdiagnosis of AATD include a lack of awareness of the condition among physicians, a racially diverse population, serum AAT levels being assessed in a limited number of individuals, and lack of convenient diagnostic tools. The diagnosis of AATD is based on laboratory test results. The standard diagnostic approach involves the assessment of serum AAT levels, followed by phenotyping, genotyping, gene sequencing, or combinations of those, to detect the specific mutation. Over the past 10 years, new techniques have been developed, offering a rapid, minimally invasive, reliable alternative to traditional testing methods. One such test available in Brazil is the A1AT Genotyping Test, which simultaneously analyzes the 14 most prevalent AATD mutations, using DNA extracted from a buccal swab or dried blood spot. Such advances may contribute to overcoming the problem of underdiagnosis in Brazil and elsewhere, as well as being likely to increase the rate detection of AATD and therefore mitigate the harmful effects of delayed diagnosis.
RESUMO A deficiência de alfa-1 antitripsina (DAAT) é um distúrbio genético raro causado por uma mutação no gene SERPINA1, que codifica o inibidor de protease alfa-1 antitripsina (AAT). A DAAT predispõe os indivíduos a DPOC e doença hepática. O diagnóstico precoce é essencial para a implementação de medidas preventivas e para limitar a carga da doença. Embora diretrizes nacionais e internacionais para o diagnóstico e manejo da DAAT estejam disponíveis há 20 anos, mais de 85% dos casos não são diagnosticados e, portanto, não são tratados. No Brasil, os motivos para o subdiagnóstico da DAAT incluem o desconhecimento dos médicos sobre a condição, a diversidade racial da população, o fato de os níveis séricos de AAT serem avaliados em um número limitado de indivíduos e a falta de ferramentas diagnósticas convenientes. O diagnóstico da DAAT baseia-se em resultados de exames laboratoriais. A abordagem diagnóstica padrão envolve a avaliação dos níveis séricos de AAT, seguida de fenotipagem, genotipagem, sequenciamento gênico ou suas combinações para detecção da mutação específica. Nos últimos 10 anos, novas técnicas foram desenvolvidas, oferecendo uma alternativa rápida, minimamente invasiva e confiável aos métodos tradicionais de teste. Um desses testes disponíveis no Brasil é o teste de genotipagem A1AT, que analisa simultaneamente as 14 mutações mais prevalentes da DAAT usando DNA extraído de swab bucal ou de sangue em papel-filtro. Esses avanços podem contribuir para a superação do problema do subdiagnóstico no Brasil e em outros países, bem como podem aumentar a taxa de detecção da DAAT e, portanto, mitigar os malefícios do diagnóstico tardio.
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Humanos , Deficiência de alfa 1-Antitripsina/diagnóstico , Deficiência de alfa 1-Antitripsina/genética , Brasil , alfa 1-Antitripsina/genética , MutaçãoRESUMO
ABSTRACT Objective: Nontuberculous mycobacteria (NTM) are a heterogeneous group of bacteria that are widely distributed in nature and associated with opportunistic infections in humans. The aims of this study were to identify NTM in patients with suspected tuberculosis who presented positive cultures and to evaluate the genetic diversity of strains identified as Mycobacterium avium. Methods: We studied pulmonary and extrapulmonary samples obtained from 1,248 patients. The samples that tested positive on culture and negative for the M. tuberculosis complex by molecular identification techniques were evaluated by detection of the hsp65 and rpoB genes and sequencing of conserved fragments of these genes. All strains identified as M. avium were genotyped using the eight-locus mycobacterial interspersed repetitive unit-variable-number tandem-repeat method. Results: We found that NTM accounted for 25 (7.5%) of the 332 mycobacteria isolated. Of those 25, 18 (72%) were M. avium, 5 (20%) were M. abscessus, 1 (4%) was M. gastri, and 1 (4%) was M. kansasii. The 18 M. avium strains showed high diversity, only two strains being genetically related. Conclusions: These results highlight the need to consider the investigation of NTM in patients with suspected active tuberculosis who present with positive cultures, as well as to evaluate the genetic diversity of M. avium strains.
RESUMO Objetivo: As micobactérias não tuberculosas (MNT) são um grupo heterogêneo de bactérias amplamente distribuídas na natureza e relacionadas com infecções oportunistas em seres humanos. Os objetivos deste estudo foram identificar MNT em pacientes com suspeita de tuberculose e culturas positivas e avaliar a diversidade genética de cepas identificadas como Mycobacterium avium. Métodos: Foram estudadas amostras pulmonares e extrapulmonares provenientes de 1.248 pacientes. As amostras que apresentaram resultado positivo em cultura e negativo para o complexo M. tuberculosis na identificação molecular foram avaliadas por meio da detecção dos genes hsp65 e rpoB e de sequenciamento de fragmentos conservados desses genes. Todas as cepas identificadas como M. avium foram genotipadas pelo método mycobacterial interspersed repetitive unit-variable-number tandem-repeat com oito loci. Resultados: Das 332 micobactérias isoladas, 25 (7,5%) eram MNT. Dessas 25, 18 (72%) eram M. avium, 5 (20%) eram M. abscessus, 1 (4%) era M. gastri e 1 (4%) era M. kansasii. As 18 cepas de M. avium apresentaram alta diversidade, e apenas duas eram geneticamente relacionadas. Conclusões: Esses resultados mostram a necessidade de considerar a investigação de MNT em pacientes com suspeita de tuberculose ativa e culturas positivas e de avaliar a diversidade genética de cepas de M. avium.
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Humanos , Micobactérias não Tuberculosas/isolamento & purificação , Mycobacterium avium/genética , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Proteínas de Bactérias/genética , Variação Genética , Brasil , RNA Polimerases Dirigidas por DNA/genética , Técnicas de Tipagem Bacteriana , Chaperonina 60/genética , Mycobacterium avium/isolamento & purificação , Infecções por Mycobacterium não Tuberculosas/microbiologiaRESUMO
OBJECTIVES: HLA-B27 is strongly associated with ankylosing spondylitis (AS) and its presence helps to confirm AS diagnosis. Due to the high HLA polymorphism and the differentiated contribution of alleles and molecules encoded by them, HLA-B*27 allele identification is relevant in the clinical follow-up, diagnosis, and treatment of this spondyloarthropathy. Inexpensive genotyping techniques with high specificity and sensitivity are of great interest in histocompatibility laboratories. This work aimed to optimize HLA-B*27 genotyping by Polymerase Chain Reaction Sequence-specific Primer (PCR-SSP), which is an accessible and inexpensive technique. METHODS: The PCR-SSP was standardized using 26 HLA-B*27 positive and 3 HLA-B*27 negative samples previously defined by Polymerase Chain Reaction Sequence-specific Oligonucleotide Probes (PCR-SSOP) (medium resolution, One Lambda®) and primers described by Duangchanchot et al. (2009). For validating the technique, 397 samples were genotyped using PCR-SSP as well as PCR-SSOP. RESULTS: The PCR-SSP technique was standardized for identifying the alleles HLA-B*27:02, HLA-B*27:CAFRW (05/13/16/17/28/37/38/39/42), HLA-B*27:CAFRZ (08/26/40), HLA-B*27:09 and HLA-B*27:12, which were found in 90 positive samples (22.67%). There was 100% agreement between the two techniques for heterozygous samples; however, two homozygous samples could not be detected by PCR-SSP. CONCLUSION: The HLA-B*27 genotyping using PCR-SSP, an easy-to-use, specific, and affordable technique, was optimized for heterozygous samples. This technique may contribute to AS diagnosis.
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Humanos , Antígenos HLA-B/genética , Técnicas de Genotipagem , Teste de Histocompatibilidade , Reação em Cadeia da Polimerase , Alelos , GenótipoRESUMO
Abstract Background Lutheran and Dombrock are two blood group systems with low immunogenic antigens; they can cause mild-to-moderate transfusion reactions. For both, immunophenotyping is not performed in the pretransfusion routine in Brazil. In addition, the distribution of their antigenic frequencies is an important marker of ethnicity. Thus, the goal of this study was to carry out the genotyping of the LU*01, LU*02, DO*01 and DO*02 alleles of the Lutheran and Dombrock blood group systems in blood donors from the southwestern region of the state of Paraná, Southern Brazil. Method Genotyping was performed for 251 blood donors by specific allele-polymerase chain reaction. The genotype and allele frequencies were obtained through direct counting and compared with other Brazilian populations using the chi-square test with Yates correction. Results The distribution of genotype frequencies for LU were 0.4% for LU*01/LU*01, 6.8% for LU*01/LU*02 and 92.8% for LU*02/LU*02 and for DO, they were 19.9% for DO*01/DO*01, 44.6% for DO*01/DO*02 and 35.5% for DO*02/DO*02. The allele and genotype frequencies of LU and DO were similar to those expected for Caucasians, but the DO*01/DO*01 genotype frequency was different to other Brazilian populations. The rare LU*01/LU*01 genotype was found in a loyal blood donor. Conclusion The genotyping techniques allowed the evaluation of the LU*01, LU*02, DO*01 and DO*02 alleles in blood donors registered in the Hemotherapy Center of the southwestern region of Paraná, Southern Brazil, and contributed to a genotyped blood donor database.
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Humanos , Antígenos de Grupos Sanguíneos , Técnicas de Genotipagem , Sistema do Grupo Sanguíneo LutheranRESUMO
ABSTRACT - This report presents three patients diagnosed with macular dystrophies with variants in PRPH2. Peripherin-2, the protein of this gene, is important in the morphogenesis and stabilization of the photoreceptor outer segment. Peripherin-2 deficiencies cause cellular apoptosis. Moreover, pathogenic variants in PRPH2 are associated with various diseases, such as pattern, butterfly-shaped pattern, central areolar, adult-onset vitelliform macular, and cone-rod dystrophies as well as retinitis pigmentosa, retinitis punctata albescens, Leber congenital amaurosis, fundus flavimaculatus, and Stargardt disease.
RESUMO - Este relato apresenta três pacientes com diagnóstico de distrofias maculares com mutações no PRPH2. Periferina 2, a proteína deste gene, é importante na morfogênese e estabilização do segmento externo dos fotorreceptores. Deficiências de periferina 2 causam apoptose celular. Além disso, variantes patogênicas no PRPH2 estão relacionadas a diferentes doenças, como distrofia padrão, distrofia padrão em asa de borboleta, distrofia central areolar, distrofia viteliforme do adulto, retinose pigmentar, distrofia de cones e bastonetes, retinite punctata albscens, amaurose congênita de Leber, fundus flavimaculatus e doença de Stargardt.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Distrofias Retinianas/genética , Distrofias Retinianas/diagnóstico por imagem , Periferinas/genética , Degeneração Macular/genética , Degeneração Macular/diagnóstico por imagem , Mutação , Angiofluoresceinografia/métodos , Tomografia de Coerência Óptica/métodos , Distrofias Retinianas/patologia , Degeneração Macular/patologiaRESUMO
BACKGROUND: Lutheran and Dombrock are two blood group systems with low immunogenic antigens; they can cause mild-to-moderate transfusion reactions. For both, immunophenotyping is not performed in the pretransfusion routine in Brazil. In addition, the distribution of their antigenic frequencies is an important marker of ethnicity. Thus, the goal of this study was to carry out the genotyping of the LU*01, LU*02, DO*01 and DO*02 alleles of the Lutheran and Dombrock blood group systems in blood donors from the southwestern region of the state of Paraná, Southern Brazil. METHOD: Genotyping was performed for 251 blood donors by specific allele-polymerase chain reaction. The genotype and allele frequencies were obtained through direct counting and compared with other Brazilian populations using the chi-square test with Yates correction. RESULTS: The distribution of genotype frequencies for LU were 0.4% for LU*01/LU*01, 6.8% for LU*01/LU*02 and 92.8% for LU*02/LU*02 and for DO, they were 19.9% for DO*01/DO*01, 44.6% for DO*01/DO*02 and 35.5% for DO*02/DO*02. The allele and genotype frequencies of LU and DO were similar to those expected for Caucasians, but the DO*01/DO*01 genotype frequency was different to other Brazilian populations. The rare LU*01/LU*01 genotype was found in a loyal blood donor. CONCLUSION: The genotyping techniques allowed the evaluation of the LU*01, LU*02, DO*01 and DO*02 alleles in blood donors registered in the Hemotherapy Center of the southwestern region of Paraná, Southern Brazil, and contributed to a genotyped blood donor database.
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Abstract Objective: To determine the relationship between the Serotonin transporter SLC6A4 (5-HTTLPR) gene polymorphism in cheilitis angularis patients. Material and Methods: We conducted a descriptive analysis of 100 DNA samples extracted from the blood serum of 50 patients with cheilitis angularis and 50 patients without cheilitis angularis. Analysis of the Serotonin transporter SLC6A4 (5-HTTLPR) gene polymorphism was observed by carrying out PCR method followed by electrophoresis for the analysis, without the usage of restriction enzyme. The Chi-square test was used for statistical analysis Results: In the cheilitis angularis group there were 24 samples with SS genotype, 23 samples with LS genotype, and 3 samples with LL genotype. Whereas in the non-cheilitis angularis group, there were 5 samples with SS genotype, 18 samples with LS genotype, and 27 samples with LL genotype. In the cheilitis angularis group found 71 S alleles and 29 L alleles, and in the non-cheilitis angularis group 28 S alleles and 72 L alleles were found. A statistically significant difference was found between the groups (p<0.001) Conclusion: There were significant differences in the distribution of the Serotonin transporter SLC6A4 (5-HTTLPR) gene polymorphism between patients with and without cheilitis angularis.
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Humanos , Masculino , Feminino , Polimorfismo Genético , Proteínas da Membrana Plasmática de Transporte de Serotonina , Técnicas de Genotipagem/instrumentação , Genes , Distribuição de Qui-Quadrado , Queilite , Estatísticas não Paramétricas , IndonésiaRESUMO
Objective: Comparing the costs and effectiveness of plasma genotyping versus tumor genotyping for detecting the T790M mutation in advanced non-small cell lung cancer (NSCLC) with a mutation in the epidermal growth factor receptor (EGFR) and that progressed after use of an EGFR tyrosine kinase inhibitor (EGFR-TKI), from the perspective of the private healthcare system in Brazil. Methods: Patients with a post-EGFR-TKI T790M mutation are eligible for a second-line treatment with a third-generation EGFR-TKI (osimertinib). In order to estimate the costs associated with the diagnosis method for the T790M mutation, a decision tree model has been used. Resource use was estimated by a team of experts, and the direct costs were estimated based on official databases. Results: Plasma genotyping provided a R$391 reduction per patient, due to the reduced cost with complications; it prevented 40.96% of the patients from undergoing an invasive procedure and 31.91% of the patients from having any kind of complication. Conclusion: Data found support a new paradigm for treating the resistance to EGFR-TKIs, with plasma genotyping as the first diagnostic choice, what can help to define the treatment and to reduce the costs of Brazilian private healthcare system.
Objetivo: Comparar os custos e efetividade da biópsia líquida versus biópsia tecidual para detecção da mutação T790M no câncer de pulmão de não pequenas células (CPNPC) avançado com mutação no receptor do fator de crescimento epidérmico (EGFR) e que progrediram após o uso de um inibidor do sítio da tirosina cinase associada ao EGFR (EGFR-TKI), sob a perspectiva do sistema suplementar de saúde do Brasil. Métodos: Pacientes com mutação EGFR-T790M pós-EGFR-TKI são elegíveis ao tratamento de segunda linha com um EGFR-TKI de terceira geração (osimertinibe). Para a estimativa dos custos relacionados ao método de diagnóstico de mutação T790M, foi elaborado um modelo de árvore de decisão. A utilização de recursos foi estimada por painel de especialistas e os custos diretos foram estimados utilizando-se bases de dados oficiais. Resultados: A biópsia líquida proporcionou redução de R$ 391 por paciente, devido a uma redução no custo com complicações; evitou que 40,96% dos pacientes passassem por um procedimento invasivo e que 31,95% dos pacientes tivessem algum tipo de complicação. Conclusão: Os dados observados embasam um novo paradigma para o manejo da resistência aos EGFR-TKIs, com genotipagem pelo plasma como primeira opção diagnóstica, o que pode auxiliar na melhor definição do tratamento e reduzir custos ao sistema de saúde suplementar brasileiro.
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Humanos , Receptores ErbB , Análise Custo-Benefício , Carcinoma Pulmonar de Células não Pequenas , Saúde Suplementar , Técnicas de GenotipagemRESUMO
ABSTRACT INTRODUCTION: Deoxyribonucleic acid (DNA) is the raw material for genetic studies, and therefore laboratory techniques are developed to obtain it with appropriate concentration and integrity. OBJECTIVE: To compare two methods of DNA extraction regarding sample concentration and integrity. METHODS: DNA was extracted from the tail end (2 mm long) of mice, stored at -20ºC. The proteinase K method (PKM) and the Kappa Express Extract® kit were used for extraction. The concentrations and ratios 260/280 and 260/230 were determined by spectrophotometry. DNA integrity was checked on 2% agarose gel with ethidium bromide. For the final test of the extracted samples, a multiplex polymerase chain reaction (PCR) was performed, with primers for the Large gene. RESULTS: Samples extracted by the PKM presented mean concentration value of 59.4 ± 18.5 ng/µl (260/280 = 1.74 ± 0.04 and 260/230 + 1.85 ± 0.14) and the samples extracted by the commercial kit presented mean concentration value of 178.8 ± 42.0 ng/µl (260/280 = 1.09 ± 0.04 and 260/230 = 0.62 ± 0.66). PCR amplified the Large gene in the DNA extracted, regardless of the methodology used. CONCLUSION: Both methodologies studied can be used, and the PKM is cheap but a time-consuming method, while the commercial kit is more expensive, however DNA extraction is faster.
RESUMO INTRODUÇÃO: O ácido desoxirribonucleico (DNA) é a matéria-prima para os estudos genéticos, por isso são desenvolvidas técnicas laboratoriais para sua obtenção, com concentração e integridades adequadas. OBJETIVO: Comparar dois métodos de extração de DNA em relação à concentração e à integridade da amostra. MÉTODOS: O DNA foi extraído da extremidade das caudas (2 mm de comprimento) de camundongos, as quais foram estocadas a -20ºC. Utilizou-se a metodologia de extração com proteinase K (MPK) e o kit Kappa Express Extract®. As concentrações e as relações 260/280 e 260/230 foram determinadas por espectrofotometria. A integridade do DNA foi verificada em gel de agarose a 2%, com brometo de etídeo. Para o teste final das amostras extraídas, realizou-se reação em cadeia da polimerase (PCR) multiplex, com primers para o gene Large. RESULTADOS: As amostras extraídas pela MPK apresentaram concentração média de 59,4 ± 18,5 ng/µl (260/280 = 1,74 ± 0,04 e 260/230 + 1,85 ± 0,14) e as extraídas pelo kit comercial, concentração média de 178,8 ± 42 ng/µl (260/280 = 1,09 ± 0,04 e 260/230 = 0,62 ± 0,66). A PCR amplificou o gene Large no DNA extraído, independente da metodologia utilizada. CONCLUSÃO: As metodologias estudadas podem ser utilizadas, sendo a MPK uma metodologia barata, porém demorada, enquanto o kit comercial é mais oneroso, contudo a extração do DNA é célere.
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ABSTRACT BACKGROUND: Celiac disease is an autoimmune enteropathy triggered by the ingestion of gluten in genetically susceptible individuals. Almost all celiac patients carry immune recognition genes coding for HLA-DQ2.5 and DQ8 heterodimers. Over the last few years, great importance has been given to HLA-DQ2.2 as probable predisposing variant, although controversies still exist regarding its relevance. OBJECTIVE: The aim of our study was to determine the possible existence of an association between HLA-DQ2.2 and celiac disease in Brazilian children by analyzing the prevalence of the predisposing variants for celiac disease in a representative group of children of a population in which this determination is still missing. METHODS: HLA-DQ typing was performed in samples from a group of celiac (n=100) and non-celiac children (n=110). All samples were tested for the presence of the following variants: DQA1*05-DQB1*02 (DQ2.5), DQA1*03-DQB1*03:02 (DQ8) and DQA1*02:01-DQB1*02:02 (DQ2.2). Fisher`s exact test was used for statistical analysis. RESULTS: In the group of 100 celiac children, 78 (78%) were positive for DQ2, 13 (13 %) were DQ2/DQ8 and 6 (6%) were DQ8 positives. The HLA-DQ pattern in the 110 non-celiac children was as follows: positive for DQ2 in 33 (29.9%) samples, in 2 (1.8 %) was positive for DQ2/DQ8 and in 15 (13.6%) was positive for DQ8. We found significant differences between the distribution of some but not all of the analyzed alleles when comparing celiac and non-celiac children. CONCLUSION: The genotyping of celiac disease HLA-DQ predisposing alleles showed similarities with HLA-DQ patterns found in both European and non-European populations, which may be a reflection of the miscegenation, which gave origin to the current Brazilian population. No significant association was found between DQ2.2 variant and celiac disease in the studied population.
RESUMO CONTEXTO: A doença celíaca é uma enteropatia autoimune, desencadeada pela ingestão do glúten em indivíduos geneticamente predispostos. Quase todos os pacientes celíacos possuem genes que codificam os heterodímeros HLA-DQ2.5 e DQ8. Nos últimos anos, mesmo com algumas controvérsias a respeito, tem se dado grande importância ao HLA-DQ2.2 como outra provável variante predisponente para doença celíaca. OBJETIVO: O objetivo do nosso trabalho foi determinar a provável associação entre HLA-DQ2.2 e a doença celíaca em crianças brasileiras, mediante a análise da prevalência das variantes predisponentes para doença celíaca em um grupo representativo desta população que ainda carece de dita informação. MÉTODOS: A genotipagem das variantes HLA-DQ foi realizada em populações de crianças celíacas (n=100) e não celíacas (n=110). A presença das seguintes variantes foi testada em todas as amostras: DQA1*05-DQB1*02 (DQ2.5), DQA1*03-DQB1*03:02 (DQ8) e DQA1*02:01-DQB1*02:02 (DQ2.2). A análise estatística foi realizada utilizando o teste exato de Fisher. RESULTADOS: No grupo de 100 crianças celíacas, 78 (78%) foram positivas para DQ2, 13 (13%) para DQ2/DQ8 e 6 (6%) foram DQ8 positivas. O padrão de variantes predisponentes no grupo de 110 crianças não celíacas foi: 33 (29.9%) amostras positivas para DQ2, 2 (1.8%) DQ2/DQ8 positivas e 15 (13.6%) DQ8 positivas. Quando as prevalências de ambos grupos foram compradas, foram achadas diferenças significativas entre algumas, mas não todas as variantes predisponentes. CONCLUSÃO: A genotipagem das variantes HLA-DQ predisponentes para doença celíaca mostrou um padrão similar ao achado em populações europeias e não-europeias, o qual pode ser resultado da miscigenação que deu origem à população brasileira atual. Nosso trabalho não mostrou associação significativa entre a variante DQ2.2 e a doença celíaca na população estudada.
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Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Antígenos HLA-DQ/genética , Doença Celíaca/genética , Predisposição Genética para Doença , Genótipo , Brasil , Estudos de Casos e Controles , AlelosRESUMO
In order to investigate killer immunoglobulin-like receptors (KIR) and their ligands, human leukocyte antigen (HLA), diversity in the Brazilian population influenced by migrations, unrelated Brazilian Japanese descendants were selected and genotyped for the KIR genes and HLA class I allele groups. Genetic heterogeneity in Brazil Paraná Japanese was observed for KIR genes, whose frequency distributions demonstrated similarity with mixed Brazilian populations and with the Japanese population, suggesting gene flow. The data contributed to the identification of the genetic constitution of the Brazilian population influenced by immigrations and two new genotypes were defined.
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Povo Asiático/genética , Fluxo Gênico/genética , Antígenos HLA/genética , Migração Humana , Receptores KIR/genética , Alelos , Brasil , Variação Genética , HumanosRESUMO
Bacterial genotyping methods have been used in several areas of microbiology and have facilitated the identification of bacterial strains, as well as the study of virulence and resistance factors, epidemiological surveillance, among others. Constituting, in this way, as complementary or alternative to phenotypic methods. This chapter reviews some of the methods of bacterial genotyping used nowadays, explains briefly how they are performed, and highlights some limitations and advantages they have.
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Bactérias/classificação , Bactérias/genética , Técnicas de Genotipagem , Hibridização Genômica Comparativa , Eletroforese em Gel de Campo Pulsado , Genoma Bacteriano , Genômica/métodos , Genótipo , Tipagem de Sequências Multilocus , Polimorfismo de Fragmento de Restrição , Sequenciamento Completo do GenomaRESUMO
Maternal RhD alloimmunization is an inflammatory response against protein antigens in fetal red blood cells (RBC). However, not all women become alloimmunized when exposed to RhD+ fetal RBC. Thus, this study aimed to evaluate levels of inflammatory chemokines in RhD- pregnant women with erythrocyte alloimmunization. CXCL8, CXCL9, CCL5, and CXCL10 levels were determined from cell culture supernatants by flow cytometry in 46 (30 non-alloimmunized RhD- and 16 previously alloimmunized RhD-) pregnant women. CXCL8 levels were significantly higher (P < 0.004), and CXCL9 (P < 0.008) and CXCL10 (P < 0.003) levels were significantly lower in alloimmunized pregnant women. No significant difference in CCL5 levels was detected between the groups. Fetal RHD genotyping was performed in the alloimmunized RhD- group by real-time PCR. Anti-D alloantibody was detected in 10 mothers and anti-D and -C in six mothers. Twelve fetuses were RHD positive and four were RHD negative. Further studies of serum chemokines and placenta tissue could provide a better understanding of the cells involved in the pathogenesis of maternal erythrocyte alloimmunization.
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OBJECTIVE: To examine the accuracy of fetal RHD genotype and RHD pseudogene determination in a multiethnical population. METHODS: Prospective study involving D-negative pregnant women. Cell-free DNA was extracted from 1 ml of maternal plasma by an automated system (MagNA Pure Compact, Roche) and real-time PCR was performed in triplicate targeting the RHD gene exons 5 and 7. Inconclusive samples underwent RHD pseudogene testing by real-time PCR analysis employing novel primers and probe. RESULTS: A positive result was observed in 128/185 (69.2%) samples and negative in 50 (27.0%). Umbilical cord blood phenotype confirmed all cases with a positive or negative PCR result. Seven (3.8%) cases were found inconclusive (exon 7 amplification only) and RHD pseudogene testing with both conventional and real-time PCR demonstrated a positive result in five of them, while two samples were also RHD pseudogene negative. CONCLUSION: Real-time PCR targeting RHD exons 5 and 7 simultaneously in maternal plasma is an accurate method for the diagnosis of fetal D genotype in our population. The RHD pseudogene real-time PCR assay is feasible and is particularly useful in populations with a high prevalence of this allele.
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Técnicas de Genotipagem/métodos , Diagnóstico Pré-Natal/métodos , Pseudogenes/genética , Sistema do Grupo Sanguíneo Rh-Hr/genética , Adulto , DNA/sangue , DNA/química , DNA/genética , Feminino , Humanos , Gravidez , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto JovemRESUMO
ABSTRACT This article provides a review of immunity, diagnosis, and clinical aspects of rotavirus disease. It also informs about the changes in epidemiology of diarrheal disease and genetic diversity of circulating group A rotavirus strains following the introduction of vaccines. Group A rotavirus is the major pathogen causing gastroenteritis in animals. Its segmented RNA genome can lead to the emergence of new or unusual strains in human populations via interspecies transmission and/or reassortment events.
RESUMO Este artigo fornece uma revisão sobre imunidade, diagnóstico e aspectos clínicos da doença causada por rotavírus. Também aponta as principais mudanças no perfil epidemiológico da doença diarreica e na diversidade genética das cepas circulantes de rotavírus do grupo A, após a introdução vacinal. O rotavírus do grupo A é o principal patógeno associado à gastroenterite em animais. Seu genoma RNA segmentado pode levar ao surgimento de cepas novas ou incomuns na população humana, por meio de transmissão entre espécies e eventos de rearranjo.