Abstract Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was the responsible for the coronavirus disease 2019 (COVID-19) pandemic. Because of its high transmissibility, allied to the emergence of some variants of concern (VOC), like Alpha, Beta, Gamma, Delta, and Omicron, the detection of these strains must be rapid and efficient. Among the tests available, the reverse-transcriptase polymerase-chain reaction (RT-PCR) is considered the gold standard test for COVID-19 detection, and the use of specific primers and probes can discriminate the different COVID-19 variants. In this study, we screened 317 individuals tested positive for COVID-19 from the municipality of Ponta Grossa (Paraná State, Brazil), from April/2021 to February/2022, aiming to identify the Gamma, Delta, and Omicron variants, by RT-PCR, using specific probes. The Gamma variant was detected from April/2021 to September/2021. The Delta variant was subsequently detected from August/2021 to November/2021. The Omicron variant was the unique strain detected from December/2021 to February/2022 and, because of its high rate of transmissibility, it caused a considerable increase in the number of COVID-19 infections. Mass testing is considered an important strategy for COVID-19 control and, the correct detection of new strains, could improve the knowledge about the virus´ behavior, permitting the development of drugs and optimized vaccines.

RESUMO A síndrome de Down (SD) é uma das principais causas de deficiência intelectual. Os objetivos deste estudo foram comparar parâmetros bioquímicos e hematológicos, bem como encontrar a relação triglicerídeo/colesterol da lipoproteína de alta densidade (HDL-C) e a razão neutrófilo/linfócito em indivíduos com deficiência intelectual (DI) associada ou não à SD. O principal resultado foi a diminuição do HDL-C em indivíduos com SD quando comparados àqueles com DI, sugerindo que essa modificação no perfil lipídico pode se relacionar com alterações genéticas. Portanto, pesquisas adicionais são importantes para analisar se existe ligação entre a trissomia 21 e a redução dos níveis de HDL-C em indivíduos com SD.

ABSTRACT Down syndrome (DS) is one of the most leading causes of intellectual disability. The aim of this study was to compare biochemical and hematological parameters, triglyceride/high-density lipoprotein cholesterol (HDL-C) and neutrophil/lymphocyte ratios in individuals with intellectual disabilities (ID) associated or not with DS. The main result is the lower HDL-C level in individuals with DS than in the ID group, suggesting a modification in the lipid profile whose origin would lie in genetic alterations. However, further researches are important to analyze if there is any link between trisomy 21 and the reduction of plasma HDL-C levels in individuals with DS.

A contagem do reticulócitos é usada extensamente na rotina laboratorial para avaliar a atividade eritropoiética da medula óssea, e é de grande importância no diagnóstico e no prognóstico na terapia de anemias hemolíticas. São coradas com o azul de metileno novo e o azul cresil brilhante, o que conferem o aspecto característico de retículo quando observado ao microscópioótico. Critérios conhecidos foram observados para um bom desempenho da contagem manual de reticulócitos, principalmente, atenção especial nas películas do sangue durante a montagem das lâminas; contagem nos campos que não contém sobreposição celular; e também no número de células avaliadas. O objetivo deste estudo foi avaliar a variação interobservadores, analisar o erro estatístico da contagem manual dos reticulócitos, e demonstrar as limitações deste método. A análise de correlação intraclasses segundo Bartko [Psychol Rep 19:3,1966; 34:418,1974] foi usada para avaliar a concordância entre 12 observadores em um total de 25 lâminas do sangue, com contagens variadas de reticulócitos. Os resultados das análises estatísticas indicam que o erro casual, calculado como (1-r2) variou de 4 a 60% entre os observadores. Embora ocorra imprecisão entre os observadores, o perfil geral entre eles é similar, e o coeficiente de correlação intraclasse indicou que os resultados obtidos são clinicamente úteis.

Reticulocyte counts are widely used in laboratories to evaluate bone marrow erythropoietic activity and have great diagnostic and prognostic importance in the treatment of anemias. Reticulocytes are supravitally stained with new methylene blue or brilliant cresyl blue, which highlight the characteristic aspect of the reticulum visible by light microscopy. Known criteria were observed for good manual reticulocyte counting with special attention being paid to the preparation of reticulocyte slides, to counting fields without overlapping cells, and to the number of evaluated cells. The aim of this study was to evaluate the inter-observer variation and also to analyze the statistical error of manual reticulocyte counting. The Intraclass correlation coefficient (ICC) according to Bartko was used to evaluate the level of agreement among 12 laboratory technicians who evaluated the same 25 blood smears. The results of statistical analyses showed that the amount of random error, defined as (1-r2), varied from 4% to 60% among the technicians. Although imprecision occurred, the overall profiles were quite similar, and intraclass correlation coefficients indicated that the results obtained have clinical significance.