Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
BMC Cancer ; 21(1): 193, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632153

RESUMO

BACKGROUND: KRAS is the most frequently mutated oncogene in cancer, however efforts to develop targeted therapies have been largely unsuccessful. Recently, two small-molecule inhibitors, AMG 510 and MRTX849, have shown promising activity in KRAS G12C-mutant solid tumors. The current study aims to assess the molecular profile of KRAS G12C in colorectal (CRC) and non-small-cell lung cancer (NSCLC) tested in a clinical certified laboratory. METHODS: CRC and NSCLC samples submitted for KRAS testing between 2017 and 2019 were reviewed. CRC samples were tested for KRAS and NRAS by pyrosequencing, while NSCLC samples were submitted to next generation sequencing of KRAS, NRAS, EGFR, and BRAF. RESULTS: The dataset comprised 4897 CRC and 4686 NSCLC samples. Among CRC samples, KRAS was mutated in 2354 (48.1%). Most frequent codon 12 mutations were G12D in 731 samples (14.9%) and G12V in 522 (10.7%), followed by G12C in 167 (3.4%). KRAS mutations were more frequent in females than males (p = 0.003), however this difference was exclusive of non-G12C mutants (p < 0.001). KRAS mutation frequency was lower in the South and North regions (p = 0.003), but again KRAS G12C did not differ significantly (p = 0.80). In NSCLC, KRAS mutations were found in 1004 samples (21.4%). As opposed to CRC samples, G12C was the most common mutation in KRAS, in 346 cases (7.4%). The frequency of KRAS G12C was higher in the South and Southeast regions (p = 0.012), and lower in patients younger than 50 years (p < 0.001). KRAS G12C mutations were largely mutually exclusive with other driver mutations; only 11 NSCLC (3.2%) and 1 CRC (0.6%) cases had relevant co-mutations. CONCLUSIONS: KRAS G12C presents in frequencies higher than several other driver mutations, and may represent a large volume of patients in absolute numbers. KRAS testing should be considered in all CRC and NSCLC patients, independently of clinical or demographic characteristics.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Colorretais/genética , Neoplasias Pulmonares/genética , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , GTP Fosfo-Hidrolases/genética , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Estudos Retrospectivos
2.
Braz J Microbiol ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39048913

RESUMO

SARS-COV-2 reinfection has been reported worldwide, although its rate remains unclear. VOC Omicron's emergence and its sub-variants led to an unprecedented number of COVID-19 cases in several countries, raising concerns regarding reinfection rates. 324,979 RT-qPCR-confirmed positive cases (72.57% from Minas Gerais State) diagnosed between April 1, 2020, and August 31, 2022, at the Hermes Pardini, Grupo Fleury (Brazil) were used to estimate the reinfection rate. Instances of reinfection were characterized by two positive tests occurring with a minimum interval of 60 days. We identified 11,669 cases of reinfection. The states of Minas Gerais, São Paulo, Rio de Janeiro and Goiás represented almost 41% of the reinfections. Up until epidemiological week 46 of 2020, only 14 cases of reinfection were recorded. The majority of reinfections, totalling 6,316 cases, were detected during the circulation period of the Omicron and its sublineages BA.1 and BA.2. Another 4,273 reinfections occurred during the circulation period of sublineages BA.4 and BA.5, revealing two distinct groups of observations. The first group comprised cases of reinfection with a shorter time interval (two infections within a period of up to 200 days), while the second group was associated with a longer time interval (two infections within a period of more than 500 days). The reinfection rate during this period was nearly 8%, which is six times higher than the rate observed at the beginning of the study. In conclusion, our study underscores the dynamic nature of SARS-CoV-2 reinfections and their correlation with emerging variants such as Omicron.

3.
Viruses ; 15(4)2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37112997

RESUMO

The introduction of SARS-CoV-2 variants of concern (VOCs) in Brazil has been associated with major impacts on the epidemiological and public health scenario. In this study, 291,571 samples were investigated for SARS-CoV-2 variants from August 2021 to March 2022 (the highest peak of positive cases) in four geographical regions of Brazil. To identify the frequency, introduction, and dispersion of SARS-CoV-2 variants in 12 Brazilian capitals, VOCs defining spike mutations were identified in 35,735 samples through genotyping and viral genome sequencing. Omicron VOC was detected in late November 2021 and replaced the Delta VOC in approximately 3.5 weeks. We estimated viral load differences between SARS-CoV-2 Delta and Omicron through the evaluation of the RT-qPCR cycle threshold (Ct) score in 77,262 samples. The analysis demonstrated that the Omicron VOC has a lower viral load in infected patients than the Delta VOC. Analyses of clinical outcomes in 17,586 patients across the country indicated that individuals infected with Omicron were less likely to need ventilatory support. The results of our study reinforce the importance of surveillance programs at the national level and showed the introduction and faster dispersion of Omicron over Delta VOC in Brazil without increasing the numbers of severe cases of COVID-19.


Assuntos
COVID-19 , Humanos , Brasil/epidemiologia , COVID-19/epidemiologia , SARS-CoV-2/genética , Mapeamento Cromossômico
4.
Viruses ; 15(2)2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36851799

RESUMO

Brazil is one of the nations most affected by Coronavirus disease 2019 (COVID-19). The introduction and establishment of new virus variants can be related to an increase in cases and fatalities. The emergence of Omicron, the most modified SARS-CoV-2 variant, caused alarm for the public health of Brazil. In this study, we examined the effects of the Omicron introduction in Minas Gerais (MG), the second-most populous state of Brazil. A total of 430 Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) samples from November 2021 to June 2022 from Belo Horizonte (BH) city were sequenced. These newly sequenced genomes comprise 72% of all previously available SARS-CoV-2 genomes for the city. Evolutionary analysis of novel viral genomes reveals that a great diversity of Omicron sublineages have circulated in BH, a pattern in-keeping with observations across Brazil more generally. Bayesian phylogeographic reconstructions indicate that this diversity is a product of a large number of international and national importations. As observed previously, São Paulo state is shown as a significant hub for viral spread throughout the country, contributing to around 70% of all viral Omicron introductions detected in MG.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Brasil/epidemiologia , COVID-19/epidemiologia , Teorema de Bayes
5.
Viruses ; 15(4)2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-37112869

RESUMO

Brazil currently ranks second in absolute deaths by COVID-19, even though most of its population has completed the vaccination protocol. With the introduction of Omicron in late 2021, the number of COVID-19 cases soared once again in the country. We investigated in this work how lineages BA.1 and BA.2 entered and spread in the country by sequencing 2173 new SARS-CoV-2 genomes collected between October 2021 and April 2022 and analyzing them in addition to more than 18,000 publicly available sequences with phylodynamic methods. We registered that Omicron was present in Brazil as early as 16 November 2021 and by January 2022 was already more than 99% of samples. More importantly, we detected that Omicron has been mostly imported through the state of São Paulo, which in turn dispersed the lineages to other states and regions of Brazil. This knowledge can be used to implement more efficient non-pharmaceutical interventions against the introduction of new SARS-CoV variants focused on surveillance of airports and ground transportation.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Brasil/epidemiologia , Meios de Transporte , Vacinação
7.
Viruses ; 14(5)2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35632589

RESUMO

Coronavirus disease 2019 (COVID-19) pandemic has caused immeasurable impacts on the health and socioeconomic system. The real-time identification and characterization of new Variants of Concern (VOCs) are critical to comprehend its emergence and spread worldwide. In this sense, we carried out a national epidemiological surveillance program in Brazil from April to October 2021. Genotyping by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and sequencing were performed to monitor the dynamics and dissemination of VOCs in samples from 15 federative units. Delta VOC was first detected on June 2021 and took sixteen weeks to replace Gamma. To assess the transmissibility potential of Gamma and Delta VOCs, we studied the dynamics of RT-qPCR cycle threshold (Ct) score in the dominance period of each variant. The data suggest that Delta VOC has a higher transmission rate than Gamma VOC. We also compared relevant symptom patterns in individuals infected with both VOCs. The Delta-infected subjects were less likely to have low oxygen saturation or fatigue, altered results on chest computed tomography, and a propensity for altered X-rays. Altogether, we described the replacement of Gamma by Delta, Delta enhanced transmissibility, and differences in symptom presentation.


Assuntos
COVID-19 , SARS-CoV-2 , Brasil/epidemiologia , COVID-19/epidemiologia , Monitoramento Epidemiológico , Humanos , SARS-CoV-2/genética
8.
Viruses ; 14(12)2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36560750

RESUMO

Since its first identification in Brazil, the variant of concern (VOC) Gamma has been associated with increased infection and transmission rates, hospitalizations, and deaths. Minas Gerais (MG), the second-largest populated Brazilian state with more than 20 million inhabitants, observed a peak of cases and deaths in March-April 2021. We conducted a surveillance study in 1240 COVID-19-positive samples from 305 municipalities distributed across MG's 28 Regional Health Units (RHU) between 1 March to 27 April 2021. The most common variant was the VOC Gamma (71.2%), followed by the variant of interest (VOI) zeta (12.4%) and VOC alpha (9.6%). Although the predominance of Gamma was found in most of the RHUs, clusters of Zeta and Alpha variants were observed. One Alpha-clustered RHU has a history of high human mobility from countries with Alpha predominance. Other less frequent lineages, such as P.4, P.5, and P.7, were also identified. With our genomic characterization approach, we estimated the introduction of Gamma on 7 January 2021, at RHU Belo Horizonte. Differences in mortality between the Zeta, Gamma and Alpha variants were not observed. We reinforce the importance of vaccination programs to prevent severe cases and deaths during transmission peaks.


Assuntos
COVID-19 , Humanos , Brasil/epidemiologia , Estudos Retrospectivos , COVID-19/epidemiologia , SARS-CoV-2 , Genômica
9.
Virus Evol ; 8(2): veac064, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35996592

RESUMO

The emergence and global dissemination of Severe Acute Respiratory Syndrome virus 2 (SARS-CoV-2) variants of concern (VOCs) have been described as the main factor driving the Coronavirus Disease 2019 pandemic. In Brazil, the Gamma variant dominated the epidemiological scenario during the first period of 2021. Many Brazilian regions detected the Delta variant after its first description and documented its spread. To monitor the introduction and spread of VOC Delta, we performed Polymerase Chain Reaction (PCR) genotyping and genome sequencing in ten regional sentinel units from June to October 2021 in the State of Minas Gerais (MG). We documented the introduction and spread of Delta, comprising 70 per cent of the cases 8 weeks later. Comparing the viral loads of the Gamma and Delta dominance periods, we provide additional evidence that the latter is more transmissible. The spread and dominance of Delta did not culminate in the increase in cases and deaths, suggesting that the vaccination may have restrained the epidemic growth. Analysis of 224 novel Delta genomes revealed that Rio de Janeiro state was the primary source for disseminating this variant in the state of MG. We present the establishment of Delta, providing evidence of its enhanced transmissibility and showing that this variant shift did not aggravate the epidemiological scenario in a high immunity setting.

10.
Mol Biol Rep ; 38(5): 3013-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20111908

RESUMO

Allelic frequencies and other population data analysis are reported for the 15 autosomal Short Tandem Repeats (STR) loci included in the PowerPlex(®)16 kit (CSF1PO, D13S317, D16S539, D18S51, D21S11, D3S1358, D5S818, D7S820, D8S1179, FGA, Penta D, Penta E, TPOX, TH01 and vWA) in Pomeranian's descendants from the Espirito Santo State (ES), Brazil, third largest population of Pomeranian's descendants in the world. They chose the mountain region of the state for their preferred geographic location, and they have a very peculiar lifestyle with a selective mating behavior which has maintained their characteristics as a relatively pure subpopulation. Blood samples were obtained from 82 unrelated volunteers from 11 different cities of Espirito Santo State, where there are the Pomeranian's descendants. All 15 loci analyzed showed Power of Discrimination (PD) values > 0.75. Except the TPOX locus, all analyzed loci were at Hardy-Weinberg equilibrium. This subpopulation has not yet been characterized for STR allelic frequencies used for forensic and genetic identification studies.


Assuntos
Variação Genética , Genética Populacional , Repetições de Microssatélites/genética , Brasil , Frequência do Gene , Genoma Humano , Humanos
12.
Science ; 372(6544): 815-821, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-33853970

RESUMO

Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , SARS-CoV-2/classificação , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Brasil/epidemiologia , Monitoramento Epidemiológico , Genoma Viral , Genômica , Humanos , Modelos Teóricos , Epidemiologia Molecular , Mutação , Ligação Proteica , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/metabolismo , Carga Viral
13.
medRxiv ; 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33688664

RESUMO

Cases of SARS-CoV-2 infection in Manaus, Brazil, resurged in late 2020, despite high levels of previous infection there. Through genome sequencing of viruses sampled in Manaus between November 2020 and January 2021, we identified the emergence and circulation of a novel SARS-CoV-2 variant of concern, lineage P.1, that acquired 17 mutations, including a trio in the spike protein (K417T, E484K and N501Y) associated with increased binding to the human ACE2 receptor. Molecular clock analysis shows that P.1 emergence occurred around early November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.4-2.2 times more transmissible and 25-61% more likely to evade protective immunity elicited by previous infection with non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.

14.
Appl Immunohistochem Mol Morphol ; 24(9): 673-678, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26258758

RESUMO

Hereditary hemochromatosis is known as the most common genetic disorder among individuals of European genetic background. It is possible to find 2 mutations closely placed in the HFE gene (H63D and S65C) and this proximity can cause errors when genotyped by real-time polymerase chain reaction (PCR) genotyping assay. The aim of this study was to develop a hydrolysis probe-based PCR assay for detection of the H63D and S65C mutations without interference from on each other. Herein the study involved the standardization of an improvement of the real-time PCR 5' nuclease assay to detect the desired mutations close placed using a same probe system. The assay analytical properties performances were tested, including the primers selectivity and detection limits. Also, the interexaminer reproducibility and repeatability of assay were estimated in 30 blood samples. Others 153 results of samples were compared with reference method (PCR_RFLP) and the accordance of the results evaluated by Fleiss' κ method. The results of variation of interexaminer reproducibility and repeatability of assay were not statistically relevant (P<0.001). The comparison between the 2 methods by Fleiss' κ analysis showed that 5' nuclease assay identified the H63D and S65C haplotype as well as the reference method in all 153 tested samples. Our results showed that novel method probe-based real-time PCR were capable to detect 2 adjacent polymorphisms without errors in genotyping.


Assuntos
Sondas de DNA , Proteína da Hemocromatose/genética , Hemocromatose/genética , Polimorfismo de Nucleotídeo Único , Reação em Cadeia da Polimerase em Tempo Real/métodos , Humanos , Reprodutibilidade dos Testes
15.
Science ; 372(6544): 1-7, 2021. graf
Artigo em Inglês | LILACS, CONASS, Coleciona SUS (Brasil), SES-SP, SES SP - Instituto Adolfo Lutz, SES-SP | ID: biblio-1247888

RESUMO

Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.


Assuntos
Angiotensinas , Genoma , Betacoronavirus
16.
Forensic Sci Int Genet ; 13: e6-e12, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24888518

RESUMO

We have reported the allele frequencies of 15 STR loci, including the original 13 CODIS core loci, in over 100,000 Brazilian individuals. A new CODIS core loci has been proposed, but the recently established Brazilian Integrated Network of DNA Databases made a decision in 2010 to postpone the implementation of this new set of loci due to the lack of allele frequency data for the Brazilian population. We aimed to report allele frequencies of 20 loci, estimated from 96,400 Brazilian individuals undergoing paternity testing during 2011-2013. The percentage of missing data was less than 0.6% for all loci, except for CSF1PO (3.15%) and D7S820 (2.5%). The dropout rates estimated by the MicroDrop software were 0.013 for CSF1PO, 0.000037 for D7S820 and less than 0.000001 for other loci. Small missing data percentages and dropout rates reflect the high quality of the data.


Assuntos
Frequência do Gene , Genética Populacional , Repetições de Microssatélites , Brasil , Impressões Digitais de DNA , Bases de Dados de Ácidos Nucleicos , Humanos , Reação em Cadeia da Polimerase
17.
Forensic Sci Int Genet ; 6(4): 504-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21813349

RESUMO

The Brazilian population is one of the most heterogeneous populations of the world, formed mainly by an admixture of European, African and Native American populations. Brazil is the fifth largest country in the world (8,511,960 km(2)), being divided into five geographical regions. This study provides population genetic data of up to 137,161 unrelated individuals representing the entire Brazilian territory. Allelic frequencies and other population data analysis are reported for the 15 autosomal STR loci included in the PowerPlex®16 kit (Promega Corporation, Madison, WI, USA). In order to guarantee that individuals were not related, we have considered only F1 data from couples undergoing paternity testing. The number of individuals genotyped for each locus was: CSF1PO (113,526); D3S1358 (135,133); D5S818 (135,181); D7S820 (137,136); D8S1179 (134,211); D13S317 (137,161); D16S539 (136,942); D18S51 (136,739); D21S11 (130,014); FGA (135,839); Penta D (110,333); Penta E (128,055); TH01 (112,695); TPOX (123,102); vWA (127,415). Allele sizes ranged from 1 to 48.2. Statistic parameters (PD, PIC and Ho; considering values ≥0.75) suggest that markers D13S317, D16S539, D18S51, D21S11, D7S820, D8S1179, Penta D, Penta E, TH01, FGA and vWA were more informative for genetic identification purposes in the Brazilian population.


Assuntos
Frequência do Gene , Genética Populacional , Repetições de Microssatélites , Brasil , Impressões Digitais de DNA/métodos , Eletroforese Capilar , Loci Gênicos , Genótipo , Humanos , Reação em Cadeia da Polimerase
18.
Forensic Sci Int Genet ; 5(3): e41-3, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20965142

RESUMO

This study provides population genetic data for individuals of Vitoria, Espirito Santo, Brazil, a location not yet characterized for STR frequencies used for genetic identification studies. Allelic frequencies and other population data analysis are reported for the 15 autosomal-STR loci included in the PowerPlex(®)16 kit (CSF1PO, D13S317, D16S539, D18S51, D21S11, D3S1358, D5S818, D7S820, D8S1179, FGA, Penta D, Penta E, TPOX, TH01 and vWA). Allele and haplotype frequencies, gene diversity and discrimination capacity were also estimated for the PowerPlex(®) Y System (DYS19, DYS385, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439). Blood samples were obtained from 226 unrelated volunteers (135 males and 91 females) residents in the city of Vitoria, representing a typical sample of the mixed ethnicity present in the Espirito Santo State, Brazil. Within the tested population, the total number of individuals typed for specific markers is: 226 for D13S317, D21S11, D3S1358, D7S820, D8S1179 and FGA; 225 for D16S539 and D5S818; 224 for D18S51; 223 for CSF1PO; 222 for Penta D and vWA; 220 for Penta E; 207 for TPOX and 142 for TH01. Y-STR haplotypes were analyzed for 102 unrelated males, being 71 of them present in the 135 autosomal-STR sample, and 31 new males tested only for Y-STR markers. All autosomal markers were in Hardy-Weinberg Equilibrium. Y-STR analysis identified 101 haplotypes, being 100 of them unique.


Assuntos
Marcadores Genéticos , Genética Populacional , Repetições de Microssatélites/genética , Brasil , Frequência do Gene , Haplótipos , Humanos , Masculino
19.
Rev. bras. anal. clin ; 40(3): 237-241, 2008. tab
Artigo em Português | LILACS | ID: lil-541912

RESUMO

A hereditariedade autossômica dominante da neoplasia endócrina múltipla tipo 2 (NEM 2) relaciona-se à ativação do proto-oncogene RET, através de mutações missense. As mutações do RET são encontradas em 95% dos casos índices de NEM 2 e apresentam relação direta entre sua localização codon específica e os diversos fenótipos desenvolvidos, dentre eles, carcinoma medular datireóide, feocromocitoma e/ou hiperparatireoidismo. Baseando-se em análises bioquímicas e genéticas, é possível efetuar um diagnósticoprematuro, viabilizando a intervenção cirúrgica em tempo hábil. A periodicidade da monitorização bioquímica é ditada pelo fenótipopresente, pelas manifestações clínicas familiares e pelo genótipo RET. A recomendação da análise genética deve ser feita a todos indivíduos afetados e também a seus ascendentes e descendentes diretos, caso alguma mutação esteja presente; permitindo identificar os portadores de mutações RET, previamente ao início da sintomatologia. Neste trabalho, serão discutidos os aspectos molecularesdos diversos fenótipos da NEM 2, bem como a importância da identificação genotípica do proto-oncogene RET e sua interação com os testes bioquímicos visando o diagnóstico precoce, prevenção, monitorização, screening familiar e, portanto, maior sobrevidado paciente.


The dominant autossomic hereditarity of the multiple endocrine neoplasia type 2 (MEN 2) is related to RET proto-oncogene activation, through mutations missense. RET mutations are found in 95% of MEN 2 index cases and present direct relation between its specific localization codon and the diverse developed phenotypes, among them, medullary thyroid carcinoma, pheochromocytoma and/or hyperparathyroidism. Being based on biochemists and genetics analyses, it is possible to perform a premature diagnosis, making possible a surgical intervention in the right time. The biochemist monitoring regularity is determined by present phenotype, the familiar clinical manifestations and RET genotype. The recommendation of the genetic analysis must be made to all affected individuals and also their ascendants and descendants, in case some mutation is present, allowing to identify the RET mutations carriers previously to the beginning of the symptomatology. In this work, the molecular aspects of MEN 2 diverse phenotypes will be discussed, as well as the importance of the RET proto-oncogene genotypic identification and its interaction with the biochemists tests aiming the precocious diagnosis, prevention, monitoring, familiar screening e, therefore, the patient’s longer survival.


Assuntos
Humanos , Carcinoma Medular , Genética Médica , Hiperparatireoidismo , Hereditariedade/genética , Feocromocitoma , Proto-Oncogenes/genética
20.
Femina ; 37(8): 423-426, ago. 2009. tab
Artigo em Português | LILACS | ID: lil-534962

RESUMO

As anomalias cromossômicas apresentam grande incidência entre os nativivos e natimortos, constituindo a maior causa de morte fetal em países desenvolvidos, no período perinatal. Tradicionalmente, o diagnóstico dessas cromossomopatias é feito por procedimentos invasivos, que não são isentos de complicações materno-fetais. O desenvolvimento de técnicas que permitem identificação e o isolamento de células fetais e de DNA fetal livre no sangue periférico materno tem permitido o diagnóstico precoce das anomalias cromossômicas, tornando-se, desse modo, uma área de intensas pesquisas. Estudos mais recentes também envolvem a identificação e quantificação de mRNA fetal na circulação materna, o que torna possível a análise da expressão gênica fetal durante a gestação. O resgate de material fetal em sangue periférico materno e sua utilização no diagnóstico de várias doenças fetais é uma área de grande interesse na medicina fetal atual. Estudos são necessários para se avaliar melhor o papel propedêutico dessas novas técnicas, assim como sua aplicabilidade na prática clínica rotineira.


Chromosomal abnormalities show great incidence among live birth and stillbirth, becoming the major fetal death cause during the perinatal period in developed countries. Traditionally, the diagnosis of these chromosomal abnormalities is performed through invasive techniques which are not free from maternal-fetal complications. The development of techniques that allows identification and isolation of fetal cells and free fetal DNA in peripheral maternal blood has afforded the early diagnosis of chromosomal abnormalities and, therefore, become an intensive area of research. Recent studies describe the identification and qualification of fetal mRNA in the maternal circulation, which makes possible fetal gene expression analysis during pregnancy. The identification of fetal material in maternal circulation and its value on the diagnosis of several fetal diseases is a great area of interest in the current fetal medicine. Studies are necessary to evaluate the best propedeutic role of these new techniques, as well as their applicability in the routine clinical practice.


Assuntos
Feminino , Gravidez , Aberrações Cromossômicas , DNA , Diagnóstico Pré-Natal/métodos , Doenças Fetais/diagnóstico , Doenças Fetais/genética , Doenças Fetais/sangue , Sangue Fetal , Reação em Cadeia da Polimerase/métodos , Trissomia/diagnóstico
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa