Background and aims: In 2013, blooms similar to those produced by Didymosphenia geminata (Lyngbye) M. Schmidt around the world, were detected in the Grande River basin, Tierra del Fuego province, and in 2014 in de las Vueltas River in Santa Cruz province. The aim of this paper is to analyze the valve morphology and morphometry of these materials to establish if they correspond to D. geminata or to other species of the genus that is producing the massive growth in southern Patagonia. M&M; Samples were collected at Grande River in 2013 and 2015 and, in de las Vueltas River in 2015 and 2016. Samples were analyzed with light and electron microscopy. For morphometric analyses 100 specimens from each sample were measured and statistical analyses were carried out using the R statistical package. Results; The studied populations have the same fine morphology described for other populations collected in Patagonia. Nevertheless, in some sampling sites from Santa Cruz province, we found a morphotype with a markedly smaller size, subcapitated poles, little marked constrictions of the poles, a broad central area (relative to cell size) and 1 to 3 stigmata, that was never reported in South America. Conclusions; The studied populations correspond to D. geminata ssp. geminata Metzeltin & Lange-Bertalot. From a morphological point of view the smaller morphotype present in Santa Cruz belongs to the same subspecies but can be easily misidentified during the routine monitoring programs carried out with light microscope due its size and valve outline.

Introducción y objetivos: En 2013 floraciones similares a las producidas por Didymosphenia geminata (Lyngbye) M. Schmidt en distintos lugares del mundo fueron detectadas en la Cuenca del Río Grande, provincia de Tierra del Fuego y, en 2014 en el río de las Vueltas en la provincia de Santa Cruz. El objetivo del trabajo fue analizar la morfología y morfometría valvar de estos materiales para establecer si corresponden a D. geminata o a otra especie del género que está produciendo floraciones masivas en la Patagonia sur. M&M; Las muestras fueron colectadas en el Río Grande en 2013 y 2015 y en el Río de las Vueltas en 2015 y 2016. El material fue analizado con microscopía óptica y electrónica. Para los análisis morfométricos fueron medidos 100 especímenes por muestra y los análisis estadísticos fueron llevados a cabo con el programa estadístico R. Resultados; Las poblaciones estudiadas presentan las mismas características morfológicas descriptas para poblaciones de distintos lugares de Patagonia. Sin embargo, en Santa Cruz observamos un morfotipo marcadamente más pequeño, con polos subcapitados, constricción suavemente marcada, un área central amplia con 1 a 3 estigmas, que no había sido descripto antes para Sudamérica. Conclusiones; Las poblaciones estudiadas corresponden a D. geminata ssp. geminata Metzeltin & Lange-Bertalot. Desde un punto de vista morfológico, los especímenes pequeños presentes en Santa Cruz pertenecen a la misma subespecie pero por su tamaño y contorno valvar pueden ser confundidos con otros taxones durante los programas de monitoreo llevados a cabo con microscopía óptica.

ABSTRACT INTRODUCTION: Human metapneumovirus (hMPV) is an emergent human respiratory pathogen. This study aimed to evaluate the performance of direct immunofluorescence (DIF) to detect hMPV in a clinical laboratory setting. METHODS: Nasopharyngeal aspirate samples (448) of children and adults with respiratory illness were used to detect hMPV by using DIF and real time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assays. RESULTS: In all, 36 (8%) samples were positive by DIF and 94 (21%) were positive by qRT-PCR. Direct immunofluorescence specificity was 99% and sensitivity was 38%. CONCLUSIONS: DIF is not very sensitive under clinical laboratory settings.

O propósito deste estudo foi avaliar o potencial proliferativo celular das lesões de líquen plano bucal (LPB) de pacientes sem vírus da hepatite C (VHC) por meio do método AgNOR, comparando-o ao potencial proliferativo celular da mucosa bucal normal de portadores de VHC, tratados ou não com interferon e ribavirina. Um estudo transversal foi realizado para investigar 4 grupos: 10 pacientes VHC+ sem sinais clínicos de LPB que nunca haviam sido tratados para a infecção por VHC - Grupo 1; 10 pacientes VHC+ que estavam sob tratamento com interferon e ribavirina - Grupo 2; 15 pacientes com LPB reticular histopatologicamente confirmado, sem VHC - Grupo 3; e 15 doadores de sangue sem infecção por VHC e sem sinais clínicos de LPB (Grupo 4 - Grupo de Controle). O material celular de todos os grupos foi coletado pela técnica da citologia em base líquida. Então, o material sedimentado de cada paciente foi submetido ao método da impregnação das regiões organizadoras nucleolares pela prata (AgNOR). A contagem das NORs foi realizada em 100 núcleos celulares epiteliais por paciente por meio do programa Image Tool(r). O teste Tukey HSD foi utilizado para comparar o valor médio de NORs entre os grupos e mostrou que a mucosa bucal dos pacientes VHC+ previamente tratados com fármacos anti-VHC (Grupo 2) apresentou maior número médio de NORs por núcleo em relação aos outros (p<0,05). O tratamento anti-VHC pode estar relacionado ao aumento da atividade proliferativa celular da mucosa bucal, aventando uma possível relação entre LPB e pacientes VHC+ tratados com interferon e ribavirina.

The objective of this study was to evaluate the cellular proliferative potential of oral lichen planus (OLP) lesions from patients without hepatitis C virus (HCV) by means of AgNOR method, as well as the cellular proliferative potential of the normal oral mucosa from patients with HCV, treated or untreated by interferon and ribavirin. A cross-sectional study was developed to investigate four groups: 10 HCV+ patients without clinical signs of OLP who had never been treated for HCV infection - Group 1; 10 HCV+ patients that were under interferon and ribavirin treatment - Group 2; 15 patients with reticular OLP lesions histopathologically confirmed, without HCV - Group 3; and 15 blood donors without HCV infection and no clinical signs of OLP GROUP 4 Control Group. The cytological material of all groups was collected by the liquid-based cytology technique. Then, the sedimented material from each patient was filled with the Nucleolar Organizer Regions impregnation by silver method (AgNOR). The count of NORs was performed on 100 epithelial cell nuclei per patient using the Image Tool(tm) software. The Tukey HSD test was used to compare the median value of NORs among the groups and showed that the oral mucosa of HCV+ patients previously treated with anti-HCV drugs (GROUP 2), presented a higher average number of NORs in relation to others (p<0.05). The anti-HCV treatment may be related to increased cell proliferation of oral mucosa, indicating a possible relationship between OLP and HCV+ patients treated with interferon and ribavirin.

The neuraminidase (NA) genes of A(H1N1)pdm09 influenza virus isolates from 306 infected patients were analysed. The circulation of oseltamivir-resistant viruses in Brazil has not been reported previously. Clinical samples were collected in the state of Rio Grande do Sul (RS) from 2009-2011 and two NA inhibitor-resistant mutants were identified, one in 2009 (H275Y) and the other in 2011 (S247N). This study revealed a low prevalence of resistant viruses (0.8%) with no spread of the resistant mutants throughout RS.