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A acromatopsia é uma doença rara, também conhecida como monocromacia de bastonetes, geralmente diagnosticada precocemente nos primeiros meses de vida. Apresenta limitação visual importante como visão diurna severamente prejudicada, baixa acuidade visual, fotofobia, nistagmo, graus variados de degeneração dos cones, além de em alguns casos ter hipermetropia, miopia e estrabismo unilateral ou bilateral. Por ser uma doença rara, existem pzSoucas evidências quanto à eficiência de um tratamento que proporcione um impacto significativo na qualidade de vida dos portadores. fatores genéticos estão diretamente relacionados à doença, onde até 80% dos pacientes com a síndrome carregam mutações no gene CNGA3 ou CNGB3. Este relato de caso apresenta um paciente com acromatopsia incompleta sendo esta condição ainda mais rara, visto que grande parte dos pacientes possuem a ACM completa. Associada a mutação no gene CNGB3 cujo a síndrome genética foi identificada apenas no DNA paterno. Atualmente o caso continua em investigação em busca de uma anomalia por parte materna.

The relationship between N-antigen concentration and viral load within a specimen and across different specimens is essential for interpretation of rapid diagnostic tests (RDT) clinical performance in different use cases. A prospective study was conducted in Porto Velho, Brazil, to investigate RDT performance in different specimen types as a function of the correlation between antigen concentration and viral load. The study included 214 close contacts with recent exposures to confirmed cases, aged 12 years and older and with various levels of vaccination. Antigen concentration was measured in nasopharyngeal swab (NPS), anterior nares swab (ANS), and saliva specimens. Reverse transcriptase (RT)–PCR was conducted on the NPS and saliva specimens, and two RDTs were conducted on ANS and one on saliva. Antigen concentration correlated with viral load when measured in the same specimen type but not across specimen types. Antigen levels were higher in symptomatic cases compared to asymptomatic/oligosymptomatic cases and lower in saliva compared to NPS and ANS samples. Discordant results between the RDTs conducted on ANS and the RT-PCR on NPS were resolved by antigen concentration values. The analytical limit-of-detection of RDTs can be used to predict the performance of the tests in populations for which the antigen concentration is known. The antigen dynamics across different sample types observed in SARS-CoV-2 disease progression support use of RDTs in nasal samples. Given lower antigen concentrations in saliva, tests using saliva is expected to require improved analytical sensitivity to achieve clinical sensitivity similar to testing of nasal samples.

Highlights • SARS-CoV-2 Quantification. • Multiplex one-step reaction. • High-sensitivity and specificity assay., Introduction Coronavirus disease-2019 (COVID-19) is a disease caused by Severe Acute Respiratory Syndrome Virus 2 (SARS-CoV-2) that emerged in China in late 2019. The rapid viral spread has made the disease a public health emergency of worldwide concern. The gold standard for diagnosing SARS-CoV-2 is reverse transcription followed by qualitative real-time polymerase chain reaction (RT-qPCR); however, the role of viral load quantification has not been thoroughly investigated yet. Objective The aim of this study was to develop a high-precision quantitative one-step RT-qPCR reaction using the association of the viral target and the human target in the same reaction. Methods The assay standardization involved the absolute quantification method, with serial dilutions of a plasmid with the N gene in a biological matrix to build a standard curve. Results and Discussion The results demonstrated the possibility of quantifying as few as 2.5 copies/reaction and an analysis of 244 patients with known results selected by cross-section that revealed 100% agreement with a qualitative RT-qPCR assay registered by Anvisa. In this population, it was possible to quantify patients with between 2.59 and 3.5 × 107 copies per reaction and negative patients continued to indicate the same result. Conclusion This assay can be a useful tool for a proper patient management, because the level and duration of viral replication are important factors to assess the risk of transmission and to guide decisions regarding the isolation and release of patients; an accurate diagnosis is critical information, whereas the current COVID-19 pandemic represents the biggest current global health problem.

Background Point-of-care and decentralized testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical to inform public health responses. Performance evaluations in priority use cases such as contact tracing can highlight trade-offs in test selection and testing strategies. Methods A prospective diagnostic accuracy study was conducted among close contacts of coronavirus disease 2019 (COVID-19) cases in Brazil. Two anterior nares swabs (ANS), a nasopharyngeal swab (NPS), and saliva were collected at all visits. Vaccination history and symptoms were assessed. Household contacts were followed longitudinally. Three rapid antigen tests and 1 molecular method were evaluated for usability and performance against reference reverse-transcription polymerase chain reaction (RT-PCR) on nasopharyngeal swab specimens. Results Fifty index cases and 214 contacts (64 household) were enrolled. Sixty-five contacts were RT-PCR positive during ≥1 visit. Vaccination did not influence viral load. Gamma variants were most prevalent; Delta variants emerged increasingly during implementation. The overall sensitivity of evaluated tests ranged from 33% to 76%. Performance was higher among symptomatic cases and those with cycle threshold (Ct) values 70% and almost 90% after 4 days. Conclusions The near-immediate time to results for antigen tests significantly offsets lower analytical sensitivity in settings where RT-PCR results are delayed or unavailable.

BackgroundPoint-of-care and decentralized testing for SARS-CoV-2 is critical to inform public health responses. Performance evaluations in priority use cases such as contact tracing can highlight trade-offs in test selection and testing strategies.MethodsA prospective diagnostic accuracy study was conducted among close contacts of COVID-19 cases in Brazil. Two anterior nares swabs (ANS), a nasopharyngeal swab (NPS), and saliva were collected at all visits. Vaccination history and symptoms were assessed. Household contacts were followed longitudinally. Three rapid antigen tests and one molecular method were evaluated for usability and performance against reference RT-PCR on NPS.ResultsFifty index cases and 214 contacts (64 household) were enrolled. Sixty-five contacts were RT-PCR positive during at least one visit. Vaccination did not influence viral load. Gamma variants were most prevalent; Delta emerged increasingly during implementation. Overall sensitivity of evaluated tests ranged from 33%–76%. Performance was higher among symptomatic cases and cases with Ct70% and almost 90% after four days.ConclusionsThe near immediate time-to-result for antigen tests significantly offsets lower analytical sensitivity in settings where RT-PCR results are delayed or unavailable.

Introdução: O desenvolvimento de primers é extremamente importante para pesquisas moleculares. Objetivos: O presente estudo objetivou desenhar e validar primers in silico para detecção do vírus sincicial respiratório humano (RSVH). Materiais e Métodos: Foi construído um banco de 100 sequências de genoma completo do Vírus Sincicial Respiratório Humano (RSVH) depositadas no Genbank (NCBI). Realizado um alinhamento múltiplo global utilizando o algoritimo Clustal W, mapeadas as regiões conservadas e selecionado os primers. Posteriormente submetidos a análise dos parâmetros especificidade, pela ferramenta BLAST, concentração de GC%, TMelting, comprimento, formação de dímeros e hairpin utilizando o software Oligo Analyser, validando-os para uso in vitro. Para discussão dos resultados, foram selecionados 14 primers de estudos realizados, submetidos à metodologia proposta neste estudo, comparando os dados obtidos. A região alvo escolhida foi o gene da Glicoproteína G, pela presença de sítios conservados. Resultados: Os primers amplificam um fragmento de 381pb, que submetido a uma segunda PCR, resulta em 109 pb correspondente ao tipo A do vírus e 168 pb para o tipo B, permitindo a detecção viral e a distinção de genótipos. Os primers possuem tamanho de 21 a 24 pb, com uma temperatura de melting entre 48,9 oC e 55,3 oC. A concentração de GC% varia de 33,3% a 52,4%. O número de bases complementares na análise de dímeros e hairpin manteve-se abaixo de 5 bases. A Energia Livre de Gibbs (Delta G) acima de -9 kcal.moles(-1) como desejado. Conclusão: Os valores obtidos na validação dos primers estão em concordância com os já utilizados em estudos de referência, validando assim o seu uso in vitro. Introduction: Developing primers is extremely important to molecular researches. Objectives: This study aims to drawing and validate in silico primers for detection of Human Respiratory Syncytial Virus (RSVH). Materials and Methods: It was built a database of 100 complete genome sequences of Human Respiratory Syncytial Virus (RSVH) deposited in the Genbank (NCBI), carried out a global multiple alignment using the algoritm Clustal W, thus mapping the conserved regions, and selecting primers, subsequently submitted to analysis of parameters such as specificity, by the BLAST tool, concentration of GC% TMelting, length, and formation of dimers and hairpins using the software Oligo Analyser, validating them to use in vitro. For discussion of the results, we selected 14 primers of studies already carried out and submitted the methodology proposed in this study, comparing the data obtained. The selected target region was the gene encoding the Glycoprotein G, by the presence of conserved sites. Results: The primers selected amplifies a fragment of 381 bp in the 1st PCR, which subjected to a second PCR results in 109 bp corresponding to the type A of the virus and 168 base pairs for the type Bwhat allows not only viral detection, as the distinction of the type to which it belongs. The primers have size from 21 to 24 base pairs, having a melting temperature (Tmelting) between 48,9o C and 55,3o C and GC% concentration ranging from 33.3% to 52.4%. The number of complementary bases in the dimers and hairpins analysis was maintained below 5 bases, while the Gibbs free energy (Delta G) was kept above kcal.mole -9(-1) as desired. Conclusion: All values obtained in the validation of the primers are in agreement with the ones already used in the reference studies, thereby validating its use in vitro.

Introdução: Doenças respiratórias caracterizam-se como infecções que causam obstrução da passagem de ar tanto a nível do trato respiratório superior como inferior e estão entre as infecções de maior índice de morbimortalidade do mundo. Objetivos: O presente trabalho tem como objetivo analisar as principais infecções respiratórias de importância clínica e os principais agentes etiológicos, compilando os tipos de infecções, agentes etiológicos mais prevalentes e os principais locais de estudo. Materiais e Métodos: Trata-se de uma revisão sistemática realizada mediante pesquisa de artigos publicados entre os anos de 2010 e 2016, nos idiomas Português, Espanhol e Inglês. A coleta eletrônica foi conduzida utilizando os bancos de dados MEDLINE/PubMed e BVS e usando os seguintes descritores, respiratory tract infection, epidemiology, mortality e transmission, indexados no Medical Subject Headings database (MeSH). Resultados: Seguindo os critérios de inclusão e exclusão, foram selecionados 33 estudos para revisão. Foi perceptível o alto índice de publicações do Brasil referente ao tema, seguido da China, EUA, Áustria e Reino Unido. Foi observado que grande parte dos estudos mencionou a influenza como patologia clínica predominante, ficando evidente que o principal agente causador das infecções respiratórias foi o agente etiológico viral, seguido do bacteriano. Conclusão: Constatou-se uma alta distribuição geográfica dos estudos referente ao tema, destacando o Brasil como o país com o maior número de publicações. Porém, o assunto ainda é pouco discutido frente ao grande impacto socioeconômico causado pelo mesmo. No que diz respeito aos agentes etiológicos causadores das infecções respiratórias, prevaleceram os vírus, sugerindo então um melhor esquema de diagnóstico a cerca desse tipo de infecção. Introduction: Respiratory diseases are defined as infections that obstruct the air passage both at the upper and lower respiratory tract and are among the infections with the highest morbidity and mortality rate in the world. Objectives: This study aims to analyze the respiratory infections of clinical importance and their main etiological agents, compiling the types of infections, the most prevalent etiological agents, and the main study sites. Materials and Methods: This is a systematic review performed through articles published between 2010 and 2016 in Portuguese, Spanish, and English. The electronic collect was conducted using the MEDLINE / PubMed and BVS databases and using the following descriptors, respiratory tract infection, epidemiology, mortality, and transmission, indexed in Medical Subject Headings database (MeSH). Results: Following the inclusion and exclusion criteria, 33 studies were selected for review. It was noticeable the high index of publications of Brazil referring to the subject, followed by China, USA, Austria and United Kingdom. It was observed that most of the studies mentioned influenza as the predominant respiratory clinical pathology. It is evident that the main cause of the respiratory infections was the viral etiologic agent followed by bacteria. Conclusion: We found a high geographical distribution of the studies related to the topic, where Brazil was highlighted as the country in which there were more publications. However, the subject is still little discussed given the socioeconomic impact caused by it. Concerning the etiological agents that cause respiratory infections, viruses prevailed, suggesting a better diagnostic approach to this type of infection.