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OBJECTIVE: The aim of this study was to analyse the attributable risk of mortality and DALYs (Disability Adjusted Life Years) due to occupational carcinogens for lung cancer between 1990 and 2019 in Brazil and federation units, as well as its relationship with the Socio-demographic Index (SDI). STUDY DESIGN: Epidemiological study. METHODS: This is an epidemiological study that used GBD 2019 (Global Burden of Disease Study) estimates of lung cancer mortality rates and DALYs attributable to occupational carcinogens. The relationship between these rates and SDI was assessed using panel data analysis. RESULTS: In Brazil, occupational exposure to asbestos, silica and diesel vapours accounted for more than 85.00% of lung cancer deaths and DALYs attributable to occupational carcinogens in both sexes between 1990 and 2019. An increase in both rates was observed in women for almost all the occupational carcinogens assessed, especially in the North and Northeast regions of the country, with diesel vapours standing out the most. CONCLUSIONS: The present study highlighted the urge to characterise exposure to occupational risks for lung cancer, especially for the female population in the North and Northeast regions of Brazil.

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Influenza affects approximately 10% of the world's population annually. It is associated with high morbidity and mortality rates due to its propensity to progress to severe acute respiratory infection, leading to 10-40% of hospitalized patients needing intensive care. Characterizing the multifactorial predictors of poor prognosis is essential for developing strategies against this disease. This study aimed to identify predictors of disease severity in influenza A-infected (IFA-infected) patients and to propose a prognostic score. A retrospective cross-sectional study was conducted with 142 IFA-infected out- and inpatients treated at a tertiary hospital between 2010 and 2018. The viral subtypes, hemagglutinin mutations, viral load, IL-28B SNPs, and clinical risk factors were evaluated according to the patient's ICU admission. Multivariate analysis identified the following risk factors for disease severity: neuromuscular diseases (OR = 7.02; 95% CI = 1.18-41.75; p = 0.032), cardiovascular diseases (OR = 5.47; 95% CI = 1.96-15.27; p = 0.001), subtype (H1N1) pdm09 infection (OR = 2.29; 95% CI = 1.02-5.15; p = 0.046), and viral load (OR = 1.43; 95% CI = 1.09-1.88; p = 0.009). The prognosis score for ICU admission is based on these predictors of severity presented and ROC curve AUC = 0.812 (p < 0.0001). Our results identified viral and host predictors of disease severity in IFA-infected patients, yielding a prognostic score that had a high performance in predicting the IFA patients' ICU admission and better results than a viral load value alone. However, its implementation in health services needs to be validated in a broader population.

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Strategies for flood control associated to extreme precipitation events in urban areas are urgent, in order to prevent not only material damages but also to avoid human losses. The construction of flood contention reservoirs ("piscinões") has become a common engineering intervention in urban and peri-urban areas. However, there is a lack of studies focused on the evaluation of environmental impacts of this type of construction. This study intended to verify the ecological effects of a retention reservoir built directly on the course of the Cascata stream, Botucatu (SP). Three sampling sites were selected, located upstream the reservoir, in the reservoir and downstream. Samplings were carried out in July (winter - dry) and November (late spring - rainy) 2020. In situ measurements were obtained through a multiparameter probe (temperature, pH, electrical conductivity, dissolved oxygen, total dissolved solids, and oxidation-reduction potential) and water samples were collected for laboratory determinations (nitrogen, total phosphorus, thermotolerant coliforms, and chlorophyll-a). For fish sampling, manual trawls, sieves and hand nets were used, with a sampling effort of 10 throws per artefact and site. Despite the small distance between the sampling points (~1,300 m) considerable changes in the limnological conditions and fish community structure were observed. The studied environment is originally a small river surrounded by riparian forest, but this characteristic was abruptly changed in the reservoir stretch, with the direct exposition of a much larger water surface to intense solar radiation and atmosphere exchanges. Consequently, as evidenced by the PCA analysis, there was a considerable (stream-reservoir increase) of temperature, dissolved oxygen and chlorophyll. However, this spatial trend was partially disturbed by an accidental sewage-pipe rupture (posteriorly fixed) adjacent to the first sampling point, due to a previous event of extreme precipitation, which resulted in increased values of nutrients, chlorophyll, conductivity and thermotolerant coliforms. Eleven fish species were collected (two non-native), belonging to seven families and five orders. The upstream reference point (despite not be pristine), was characterized by the predominance of native species, while the reservoir condition favored the development of large populations of the non-native species. Despite the urgency of effective actions to prevent floods in urban areas, construction of contention reservoirs directly on stream courses should be avoided, due to their negative ecological impacts.

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Interventional radiology brings extensive benefits to patients. Nevertheless, certain procedures may result in high doses of radiation, leading to health risks to occupationally exposed individuals (OEIs). Therefore, a more comprehensive risk analysis is essential to ensuring safety and minimising radiation exposures for all OEIs. The Toolkit for Safety Assessment (TOKSA) tool performs risk assessments based on the concepts described in 'General Safety Requirements' Part 3 (Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards) and Part 4 (Safety Assessment for Facilities and Activities). This tool was developed based on the 'Ibero-American Forum of Radiological and Nuclear Regulatory Agencies' risk models and can promote the use of the risk assessment processes by OEIs. The aim of this study was to experimentally analyse the applicability of the TOKSA tool in interventional radiology with the use/support of probabilistic risk assessment techniques. The results were used to reduce the risks associated with a hemodynamics room in a hospital in Belo Horizonte, Brazil.

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This research aimed to estimate the risk of cancer associated with patients without previous disease undergoing chest tomography. Siemens CT scanners have 6, 64, and 128 detectors. The Biologic Effects of Ionizing Radiation Reports - BEIR VII methodology was used. The study presented a sample of 64 patients aged between 18 and 80 years, in the city of Belo Horizonte, Minas Gerais - Brazil. The IMPACT CT software and CalDose X CT Online were used to calculate the absorbed and equivalent dose from the Volumetric Computed Tomography Dose Index - CTDIvol (mGy) and Dose Length Product - DLP values provided by the equipment. CT-Expo Software was also used to estimate Specific Dose Estimates (SSDEs) values. The CTDvol results for the MG1, MG,2 and MG3 Diagnostic Centers in mGy were respectively 4.369 ± 1.352, 6.99 4 ± 1.53,3 and 9.984 ± 2.282 and the SSDE values were 3.800, 6.40,0 and 9,.500. The values for the equivalent dose, at the MG2 Diagnostic Center, by IMPACT CT, in (mSv) for the breasts, esophagus, heart, thyroid, lung and thymus were respectively 3.9, 5.7, 4.7, 1.0, 4.8 and 5.7. The CalDose Software, for the same equipment and the same organs, in mSv, estimated the values 7.4, 9.4, 11.1, 5.3, 10.8 and 11.3 for women and 7.1, 9.3, 11.0, 5.3, 10.2 and 10.9 for men. The estimated risk of cancer decreased according to the patient's age, but with a higher incidence for females. The use of each software must be carefully analyzed to avoid undue values due to the particularities of each one. The results also showed that the risk of developing cancer due to radiation decreases with patient age and is higher in females.

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Merkel cell carcinoma (MCC) is a rare aggressive neuroendocrine cutaneous carcinoma with a high mortality rate. The MCC etiology is not fully understood. Merkel cell-associated polyomavirus (MCPyV) was found in MCC patients, indicating a risk factor for the tumor. Caucasian, elderly, and immunocompromised individuals are more likely to develop this tumor. HLA-G consists of a non-classical class I (Ib) HLA molecule with an immunoregulatory function and was associated with tumor escape in different types of tumors, nonetheless, never been studied in MCC. The purpose of this study was to evaluate the HLA-G expression and also to detect the MCPyV in MCC patients and correlate it with the clinical course of the disease. Forty-five MCC patients were included in a retrospective study. Formalin-fixed paraffin-embedded cutaneous skin biopsies were used by immunohistochemistry and RT-PCR to verify the HLA-G expression and MCPyV infection. HLA-G expression was found in 7 (15.6%), while the presence of MCPyV was detected in 28 (62.2%) of the studied patients. No significant association was found between HLA-G expression and MCPyV infection (p = 0.250). The presence of MCPyV was associated with areas of low sunlight exposure (p = 0.042) and the HLA-G expression with progression to death (p = 0.038). HLA-G expression was detected in MCC patients, as well as the MCPyV presence was confirmed. These markers could represent factors with a possible impact on patient survival; however, further studies with a greater number of patients are needed, to better elucidate the possible role in disease progression.

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The aim of the study was to investigate the nephrotoxicity of doxorubicin in cats with malignant neoplasms of the mammary gland. All selected cats did not present comorbidities such as nephropathies and/or cardiomyopathies, confirmed by physical and laboratory tests, underwent radical mastectomy associated with regional lymph node excision and were treated with a protocol based on doxorubicin. Renal markers of urea, creatinine, symmetrical dimethylarginine were evaluated during all the treatment, and two months after the end. Abdominal ultrasound, urinalysis and biochemical analysis of protein, urinary creatinine and urinary GGT were performed in the beginning and two months after the end of the treatment, to evaluate possible renal alterations. Six cats did not present renal alterations in any exams performed during the study. Two cats presented azotemia during this study, and one of them stopped the treatment early, because of the intense azotemia. Clinical imaging and laboratory monitoring of patients throughout the treatment is essential, including the measurement of analytes that detect kidney changes early. Thus, it is emphasized that doxorubicin is a safe drug for use in non-nephropathic cats.

O objetivo do estudo foi investigar a nefrotoxicidade da doxorrubicina em gatas com neoplasias malignas da glândula mamária. Todas as gatas selecionadas não apresentaram comorbidades como nefropatias e/ou cardiomiopatias, comprovadas por exames físicos e laboratoriais, foram submetidas à mastectomia radical associada à exérese de linfonodos regionais e tratadas com protocolo baseado em doxorrubicina. Os marcadores renais ureia, creatinina, dimetilarginina simétrica foram avaliados durante todo o tratamento e dois meses após o término. Ultrassonografia abdominal, urinálise e análise bioquímica de proteínas, creatinina urinária e GGT urinária foram realizadas no início e dois meses após o término do tratamento, para avaliar possíveis alterações renais. Seis gatas não apresentaram alterações renais em nenhum dos exames realizados durante o estudo. Duas gatas apresentaram azotemia durante este estudo, e uma delas interrompeu o tratamento precocemente, devido à intensa azotemia. A individualidade de cada paciente deve ser sempre considerada, pois são muitas as variáveis. O monitoramento clínico, com exames complementares, tais como bioquímicos séricos e de imagem dos pacientes durante todo o tratamento, é essencial, especialmente a mensuração de analitos que detectam alterações renais precocemente. Diante disso, ressalta-se que a doxorrubicina é um medicamento seguro para utilização em gatas não nefropatas.

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This work establishes local diagnostic reference levels (DRLs) in interventional radiology based on adult patient body mass index (BMI). The monitoring was carried out from 23 institutions and patient data from 3015 procedures were collected, being 907 Catheterism (CAT), 921 Percutaneous transluminal coronary angioplasty (PTCA) and 1187 CAT/PTCA and 6 BMI ranges were taken, going from under 18 up to 40 kg·m-2. It is presented that 18 initial DRL values to be used in the county of Minas Gerais. The overall 75th kerma-area product (KAP), commonly considered DRL, in Gy·cm2, is 94.6(SD 119)-CAT, 88.6(SD 121)-PTCA and 33.0(SD 47.6)-CAT/PTCA. In considering KAP-BMI individual values, one obtain the min-max ranges, in Gy·cm2, 3.2-BMI A to 101-BMI B for CAT, 65-BMI A to 102-BMI F for PTCA and 10.4-BMI A to 59.2-BMI E for CAT/PTCA. The KAP-BMI approach has shown to be feasible as a DRL optimization process.

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PURPOSE: This work investigated the endocytic pathways taken by poly(isobutylcyanoacrylate) (PIBCA) nanoparticles differing in their surface composition and architecture, assuming that this might determine their efficiency of intracellular drug delivery. METHODS: Nanoparticles (A0, A25, A100, R0, R25 ) were prepared by anionic or redox radical emulsion polymerization using mixtures of dextran and fucoidan (0, 25, 100 % in fucoidan). Cell uptake was evaluated by incubating J774A.1 macrophages with nanoparticles. Endocytic pathways were studied by incubating cells with endocytic pathway inhibitors (chlorpromazine, genistein, cytochalasin D, methyl-ß-cyclodextrin and nocodazole) and nanoparticle uptake was evaluated by flow cytometry and confocal microscopy. RESULTS: The fucoidan-coated PIBCA nanoparticles A25 were internalized 3-fold more efficiently than R25 due to the different architecture of the fucoidan chains presented on the surface. Different fucoidan density and architecture led to different internalization pathway preferred by the cells. Large A100 nanoparticles with surface was covered with fucoidan chains in a loop and train configuration were internalized the most efficiently, 47-fold compared with A0, and 3-fold compared with R0 and R25 through non-endocytic energy-independent pathways and reached the cell cytoplasm. CONCLUSION: Internalization pathways of PIBCA nanoparticles by J774A.1 macrophages could be determined by nanoparticle fucoidan surface composition and architecture. In turn, this influenced the extent of internalization and localization of accumulated nanoparticles within cells. The results are of interest for rationalizing the design of nanoparticles for potential cytoplamic drug delivery by controlling the nature of the nanoparticle surface.

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BACKGROUND: Although the risk of SARS-CoV-2 transmission within hospitals has been well recognized, there is a paucity of data on its occurrence. Our aim was to report the incidence of hospital-acquired (HA) COVID-19 at Brazilian hospitals. METHODS: We investigated the incidence of HA COVID-19 in Brazilian hospitals using data from a national surveillance system, from August 2020 through September 2021. Definitions of HA COVID-19 were: (1) symptom onset >14 days after hospital admission plus a positive SARS-CoV-2 RNA or antigen test; (2) symptom onset on days 8-14 after admission, plus a positive SARS-CoV-2 RNA or antigen test positive, plus documented high-risk exposure. We performed descriptive analyses and reported HA COVID-19 rates using pooled mean and percentile distribution. RESULTS: A total of 48,634 cases of HA COVID-19 were reported from 1428 hospitals. Incidence ranged from 0.16/1000 patient-days at neonatal intensive care units (ICUs) to 5.8/1000 patient-days at adult ICUs. The highest incidence of HA COVID-19 was during the months March to July 2021, similar to that which was observed for community-acquired COVID-19. CONCLUSIONS: This report provides a national view of the burden of HA COVID-19. The highest incidence of HA COVID-19 similar that which was observed for community-acquired COVID-19. We believe that this reflects the difficulty of implementing preventive measures. Further studies evaluating risk factors for the hospital transmission of SARS-Cov-2 should clarify strategies to minimize the risk of HA COVID-19 and may be applicable to other respiratory diseases. Furthermore, the implementation of a national system to evaluate HA COVID-19 has the potential to shine a light on this problem and lead to interventions in each hospital.

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Influenza is an acute viral infectious respiratory disease worldwide, presenting in different clinical forms, from influenza-like illness (ILI) to severe acute respiratory infection (SARI). Although real-time quantitative polymerase chain reaction (qPCR) is already an important tool for both diagnosis and treatment monitoring of several viral infections, the correlation between the clinical aspects and the viral load of influenza is still unclear. This lack of clarity is primarily due to the low accuracy and reproducibility of the methodologies developed to quantify the influenza virus. Thus, this study aimed to develop and standardize a universal absolute quantification for influenza A by reverse transcription-quantitative PCR (RT-qPCR), using a plasmid DNA. The assay showed efficiency (Eff%) 98.6, determination coefficient (R2) 0.998, linear range 10^1 to 10^10, limit of detection (LOD) 6.77, limit of quantification (LOQ) 20.52 copies/reaction. No inter and intra assay variability was shown, and neither was the matrix effect observed. Serial measurements of clinical samples collected at a 72h interval showed no change in viral load. By contrast, immunocompetent patients have a significantly lower viral load than immunosuppressed ones. Absolute quantification in clinical samples showed some predictors associated with increased viral load: (H1N1)pdm09 (0.045); women (p = 0.049) and asthmatics (p = 0.035). The high efficiency, precision, and previous performance in clinical samples suggest the assay can be used as an accurate universal viral load quantification of influenza A. Its applicability in predicting severity and response to antivirals needs to be evaluated.

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Merkel cell carcinoma (MCC) is a rare aggressive neuroendocrine cutaneous carcinoma with a high mortality rate. The MCC etiology is not fully understood. Merkel cell-associated polyomavirus (MCPyV) was found in MCC patients, indicating a risk factor for the tumor. Caucasian, elderly, and immunocompromised individuals are more likely to develop this tumor. HLA-G consists of a non-classical class I (Ib) HLA molecule with an immunoregulatory function and was associated with tumor escape in different types of tumors, nonetheless, never been studied in MCC. The purpose of this study was to evaluate the HLA-G expression and also to detect the MCPyV in MCC patients and correlate it with the clinical course of the disease. Forty-five MCC patients were included in a retrospective study. Formalin-fixed paraffin-embedded cutaneous skin biopsies were used by immunohistochemistry and RT-PCR to verify the HLA-G expression and MCPyV infection. HLA-G expression was found in 7 (15.6%), while the presence of MCPyV was detected in 28 (62.2%) of the studied patients. No significant association was found between HLA-G expression and MCPyV infection (p = 0.250). The presence of MCPyV was associated with areas of low sunlight exposure (p = 0.042) and the HLA-G expression with progression to death (p = 0.038). HLA-G expression was detected in MCC patients, as well as the MCPyV presence was confirmed. These markers could represent factors with a possible impact on patient survival; however, further studies with a greater number of patients are needed, to better elucidate the possible role in disease progression.

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INTRODUÇÃO: A cardiomiopatia hipertrófica apical (CMHA) ou síndrome de Yamaguchi é uma condição relativamente rara, que apresenta acometimento predominante da região apical do ventrículo esquerdo (VE). O Ecocardiograma com strain nesta condição apresenta uma redução no ápice bem semelhante à imagem obtida no Infarto Apical. Descrevemos um caso onde as duas condições estavam presentes. (Figuras 1 -4) RELATO DE CASO: Masculino, de 78 anos, previamente hipertenso, procurou o pronto socorro por dor precordial teve o diagnóstico de infarto sem supra do segmento ST. Seu eletrocardiograma evidenciava ondas T profundas na parede anterior e lateral. Submetido à estratificação invasiva, sendo evidenciada coronária direita (CD) ocluída no terço proximal (CD), com circulação colateral presente e lesão grave em terço proximal de artéria circunflexa (Cx). Foi submetido à angioplastia com stent farmacológico na CX. Um mês após o evento coronariano agudo, o paciente retorna ao serviço referindo persistência de dor precordial, semelhante ao quadro anterior. Mantinha-se em uso de dupla antiagregação plaquetária, de modo que foi optado por nova estratificação invasiva, que revelou as mesmas lesões previamente citadas, com stent farmacológico em Cx apresentando fluxo TIMI 3. Ao ECO com strain, evidenciou-se aumento isolado da espessura da região apical do VE, medindo 15mm, com contratilidade miocárdica preservada nesta região, redução do strain global de 11.2% e área de redução muito acentuada sugerindo fibrose nessa mesma região poupando as demais paredes. Neste momento, não foi possível a determinação da causa da redução do strain apical, se IAM, Takotsubo ou CMH. A ressonância magnética cardíaca (RMC) com estresse com dipiridamol observou hipertrofia miocárdica assimétrica apical com carga fibrótica de 16% e presença de isquemia miocárdica em segmentos inferosseptal e inferior medioapical, além de realce tardio de padrão não coronariano acometendo a porção apical do VE, com fração de ejeção de 66%. CONCLUSÃO: A identificação da etiologia da fibrose apical só foi possível com a ressonância magnética, que deixou claro ser decorrente da CMHA, já que o padrão de realce era não coronariano. Ao estresse com Dipiridamol, evidenciou isquemia na parede inferior e inferosseptal medioapical determinando que a dor precordial tinha como causa a circulação colateral insuficiente da CD. Concluímos pela necessidade do diagnóstico ser multimodalidades de imagem, com resultados mais conclusivos com RMC.

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INTRODUÇÃO: Miocárdio não compactado (MNC) é uma cardiopatia congênita rara que teve seu primeiro caso publicado há menos de 40 anos caracterizado pela falta de compactação miocárdica com a formação de trabéculas no ventrículo esquerdo (VE), afetando principalmente a região apical, podendo estar associado à hipertrofia e dilatação do VE. CASO: Masculino, 69 anos, praticante de atividade física (corrida de rua, 10km, 3x/semana). Durante avaliação inicial apresentava-se assintomático e exame físico normal, trazendo resultado de exames de cinco anos atrás, quando ainda era sedentário, apresentando eletrocardiograma (ECG) e ECO normais. Na admissão, apresenta ECG com bloqueio atrioventricular grau I, Teste ergométrico (TE) com boa capacidade funcional, não compatível com resposta isquêmica. O ECO evidenciou hipertrabeculação dominante no ápice do VE com disfunção global do VE (FE 40%). Na RMC mostrou uma relação entre miocárdio não compactado/compactado de 3,0 e confirmou disfunção do VE. Assim, foi realizada a hipótese diagnóstica de MNC, orientada limitação das atividades físicas a leves a moderadas e contraindicado atividades de alta intensidade além de ser iniciado tratamento para disfunção O paciente foi acompanhado com ECOs evidenciando persistência das trabeculações do VE, TE e Holter que não revelaram presença de arritmias ventriculares significativas. Na última avaliação, após um ano de sedentarismo do paciente o ECO evidenciou diminuição da trabeculação no VE e a nova RMC mostrou disfunção do VE (FE 42%) associado a um aumento discreto das trabeculações na porção apical, porém sem fechar critérios para o diagnóstico de MNC com uma relação miocárdio não compactado/compactado <2,3e com ausência de comprometimento septal. Após afastado o diagnóstico inicial, foi levantada a hipótese de miocardiopatia dilatada idiopática, orientando limitação de atividades físicas para leves a moderadas. DISCUSSÃO: Já está bem estabelecido que o treinamento físico pode estar associado a adaptações cardíacas, elétricas e estruturais, e, em casos raros, essas adaptações, tidas como fisiológicas, podem se sobrepor a expressões morfologicamente leves das cardiomiopatias primárias e resolver este dilema diagnóstico pode ser desafiador. O MNC é um distúrbio miocárdico relativamente novo, podendo levar a disfunção sistólica do VE, arritmias ventriculares e até a morte súbita. Eventualmente atletas podem exibir critérios convencionais para MNC destacando a natureza não específica dos critérios diagnósticos atuais se aplicados a populações de atletas.

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Abstract Small hydroelectric power plants (SHP) have been considered as an alternative for the generation of electricity with reduced environmental impacts. Nevertheless, no studies have addressed changes in a particular kind of river macrohabitat commonly affected by SHPs, the knickzones. This study aimed to assess the impact of a SHP construction on the aquatic macroinvertebrate fauna associated with two basaltic knickzones located in Sapucaí-Mirim River, Southeast Brazil. The first, considered as a functional knickzone, follows the natural dynamics of the river flow and preserves the original rock substrate. The second, considered as non-functional knickzone, was permanently flooded after the SHP construction and the consolidated rock substrate was changed by fine sediment. Sampling was carried out in two seasonal periods and the data were analysed through multivariate analysis. It was observed differences in composition and structure of the macroinvertebrates community between the knickzones and periods. The functional knickzone exhibited a much higher richness, 72 taxa compared to 44 in the non-functional, as well as a large number of exclusive taxa (38, being only nine exclusive to the non-functional). Diversity, equitability and density mean values were also higher in the functional knickzone. The limnological parameters varied significantly between dry and rainy seasons but not between the distinct knickzones. This kind of macrohabitats and its potential role for the rivers biodiversity is practically unknown. In the scenery of fast SHP expansion, further studies and protection measures are necessary.

Resumo Atualmente, a instalação de pequenas centrais hidrelétricas (PCHs) tem sido a alternativa mais visada quando a questão é suprir a demanda energética, considerando-se os menores impactos ambientais possíveis. Contudo, são escassos os trabalhos que avaliam as alterações causadas por esses empreendimentos, principalmente no que se diz respeito a um tipo de macro-habitat de rios, os pedrais. Assim, este estudo teve como objetivo avaliar o impacto da construção de uma PCH na fauna de macroinvertebrados aquáticos associada a dois pedrais basálticos, localizados no rio Sapucaí-Mirim, no Sudeste do Brasil. O primeiro, considerado como um pedral funcional, segue a dinâmica natural do fluxo do rio e possui o substrato rochoso original. O segundo, considerado como pedral não funcional, foi permanentemente inundado após a construção da PCH e o substrato consolidado foi alterado por sedimentos finos. A amostragem foi realizada em dois períodos sazonais e os dados foram analisados através de análise multivariada. Foram observadas diferenças na composição e estrutura da comunidade de macroinvertebrados entre os pedrais e períodos. O pedral funcional apresentou uma riqueza muito maior, 72 táxons em comparação com 44 no não funcional, bem como um grande número de táxons exclusivos (38, sendo apenas nove exclusivos do não-funcional). Os valores médios da diversidade, equitabilidade e densidade também foram maiores no pedral funcional. Os parâmetros limnológicos variaram significativamente entre as estações seca e chuvosa, mas não entre os diferentes pedrais. Este tipo de macro-habitat e seu potencial papel para a biodiversidade dos rios são praticamente desconhecidos. Assim, mais estudos e medidas de proteção são necessários, principalmente diante do atual cenário de rápida expansão das PCHs.

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The earliest stages of embryo development are deeply influenced by reactive oxygen species (ROS), byproducts of the mitochondrial oxygen metabolism that play a key role as messengers in normal cell signal transduction and cell cycling. Despite its positive roles, the imbalance caused by the excess of ROS and an inefficient antioxidant system leads to oxidative stress, with negative consequences to the cell such as DNA damage, metabolic changes, mitochondrial stress and cell death. In the present work, crocetin - a natural antioxidant - was added to the culture media of bovine embryos to evaluate the efficiency of its antioxidant capability during embryo culture. Oocytes were in vitro matured (IVM) and fertilized according to standard protocols. Embryos were cultured at 38.5 °C under humidified air with 5% CO2, 7% O2, and 90% N2 in Synthetic Oviduct Fluid (SOF) medium supplemented with amino acids and either 5% of FBS (SOFaa) (control group) or SOFaa supplemented with 1  µM crocetin (crocetin group). After 5 days from the beginning of in vitro culture (IVC) (day 5 - D5), embryos were transferred to individual drops of culture media. At day 7 (D7), embryos were assessed by means of blastocyst rates, morphophysiological analyzes (total cell number, ROS and mitochondrial activity levels), transcript quantitation of 47 genes and metabolomic evaluation of the culture media by Raman spectroscopy. In the crocetin group blastocyst rates were higher and embryos had increased total cell number and decreased intracellular levels of ROS. These embryos also had upregulation of genes related with response to stress and lipid metabolism (ATF4, BAX, FOXO3, GADD45A, GPX1, GPX4, HSF1, SOD2, ACACA, SREBF1 and SREBF2). Raman spectroscopy corroborated these results indicating more active lipid and amino acid production in this group. The absence of crocetin in the culture media resulted in higher ROS level, as well as up regulation of genes related to DNA damage, stress response and energy metabolism (MORF4L2, SOD1, TXN, PFKP, PGK1 and PPARGC1A). In conclusion, crocetin supplementation during culture protects embryos from oxidative stress and influences the adaptive response to stress conditions, leading to an increase in both blastocyst yield and quality, as well as changes in transcriptomic and metabolic profile of in vitro produced bovine embryos.

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Small hydroelectric power plants (SHP) have been considered as an alternative for the generation of electricity with reduced environmental impacts. Nevertheless, no studies have addressed changes in a particular kind of river macrohabitat commonly affected by SHPs, the knickzones. This study aimed to assess the impact of a SHP construction on the aquatic macroinvertebrate fauna associated with two basaltic knickzones located in Sapucaí-Mirim River, Southeast Brazil. The first, considered as a functional knickzone, follows the natural dynamics of the river flow and preserves the original rock substrate. The second, considered as non-functional knickzone, was permanently flooded after the SHP construction and the consolidated rock substrate was changed by fine sediment. Sampling was carried out in two seasonal periods and the data were analysed through multivariate analysis. It was observed differences in composition and structure of the macroinvertebrates community between the knickzones and periods. The functional knickzone exhibited a much higher richness, 72 taxa compared to 44 in the non-functional, as well as a large number of exclusive taxa (38, being only nine exclusive to the non-functional). Diversity, equitability and density mean values were also higher in the functional knickzone. The limnological parameters varied significantly between dry and rainy seasons but not between the distinct knickzones. This kind of macrohabitats and its potential role for the rivers biodiversity is practically unknown. In the scenery of fast SHP expansion, further studies and protection measures are necessary.

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RESUMO

Small hydroelectric power plants (SHP) have been considered as an alternative for the generation of electricity with reduced environmental impacts. Nevertheless, no studies have addressed changes in a particular kind of river macrohabitat commonly affected by SHPs, the knickzones. This study aimed to assess the impact of a SHP construction on the aquatic macroinvertebrate fauna associated with two basaltic knickzones located in Sapucaí-Mirim River, Southeast Brazil. The first, considered as a functional knickzone, follows the natural dynamics of the river flow and preserves the original rock substrate. The second, considered as non-functional knickzone, was permanently flooded after the SHP construction and the consolidated rock substrate was changed by fine sediment. Sampling was carried out in two seasonal periods and the data were analysed through multivariate analysis. It was observed differences in composition and structure of the macroinvertebrates community between the knickzones and periods. The functional knickzone exhibited a much higher richness, 72 taxa compared to 44 in the non-functional, as well as a large number of exclusive taxa (38, being only nine exclusive to the non-functional). Diversity, equitability and density mean values were also higher in the functional knickzone. The limnological parameters varied significantly between dry and rainy seasons but not between the distinct knickzones. This kind of macrohabitats and its potential role for the rivers biodiversity is practically unknown. In the scenery of fast SHP expansion, further studies and protection measures are necessary.(AU)

Atualmente, a instalação de pequenas centrais hidrelétricas (PCHs) tem sido a alternativa mais visada quando a questão é suprir a demanda energética, considerando-se os menores impactos ambientais possíveis. Contudo, são escassos os trabalhos que avaliam as alterações causadas por esses empreendimentos, principalmente no que se diz respeito a um tipo de macro-habitat de rios, os pedrais. Assim, este estudo teve como objetivo avaliar o impacto da construção de uma PCH na fauna de macroinvertebrados aquáticos associada a dois pedrais basálticos, localizados no rio Sapucaí-Mirim, no Sudeste do Brasil. O primeiro, considerado como um pedral funcional, segue a dinâmica natural do fluxo do rio e possui o substrato rochoso original. O segundo, considerado como pedral não funcional, foi permanentemente inundado após a construção da PCH e o substrato consolidado foi alterado por sedimentos finos. A amostragem foi realizada em dois períodos sazonais e os dados foram analisados através de análise multivariada. Foram observadas diferenças na composição e estrutura da comunidade de macroinvertebrados entre os pedrais e períodos. O pedral funcional apresentou uma riqueza muito maior, 72 táxons em comparação com 44 no não funcional, bem como um grande número de táxons exclusivos (38, sendo apenas nove exclusivos do não-funcional). Os valores médios da diversidade, equitabilidade e densidade também foram maiores no pedral funcional. Os parâmetros limnológicos variaram significativamente entre as estações seca e chuvosa, mas não entre os diferentes pedrais. Este tipo de macro-habitat e seu potencial papel para a biodiversidade dos rios são praticamente desconhecidos. Assim, mais estudos e medidas de proteção são necessários, principalmente diante do atual cenário de rápida expansão das PCHs.(AU)

RESUMO

The golden mussel, Limnoperna fortunei, is an Asian freshwater bivalve introduced in South America in the beginning of the 1990s, probably through ballast water releases in La Plata River estuary. It dispersed north through Paraná, Uruguay and Paraguay Rivers. The study evaluated the macroscale (18° to 34° S; 45° to 60° W) distribution of L. fortunei (larval stages) in the main rivers and reservoirs of La Plata Basin. Samplings were performed through 68 µm vertical plankton net hauls. Limnological variables were simultaneously determined. Larvae abundance correlated significantly with oxygen (positively) in summer, with temperature (positively) in winter and with total phosphorus and total nitrogen (both negatively) in winter. We expected densities to decrease towards north (latitudinal gradient) and increase in lentic conditions (reservoirs). Despite maximum density was found near the introduction point (La Plata River) similar value was also observed 2,000 km north (Paraguay River). The first hypothesis was refuted. The second hypothesis was partially accepted. Abundances were consistently higher in summer. Higher trophic conditions and fast flow seem to inhibit population growth. Food resources (chlorophyll a) locally influenced temporal variation. Limnoperna fortunei is widely distributed in La Plata basin, reaching high larval densities superior to 10,000 ind. m-3, in all major sub-basins. The species exhibits a high intrinsic dispersal ability (free planktonic larvae), wide tolerance to environmental factors and dispersion is potentialized by natural dispersion processes (e.g. fauna displacement) and human facilitation (e.g. commercial navigation).(AU)

O mexilhão dourado, Limnoperna fortunei, é um bivalve de água doce originário da Ásia e introduzido na América do Sul no início de 1990, provavelmente através da água de lastro liberada no estuário do rio La Plata. Dispersando-se para o norte através dos rios Paraná, Uruguai e Paraguai. Esse estudo avaliou a distribuição em macroescala (18° a 34° S; 45° a 60° W) de L. fortunei (estágios larvais) nos principais rios e reservatórios da bacia La Plata. Amostragens foram realizadas através de arrastos verticais com rede planctônica de 68 µm. Variáveis limnológicas foram simultaneamente determinadas. A abundância larval correlacionou-se significativamente com oxigênio (positivamente) no verão, com a temperatura (positivamente) no inverno e com fósforo total e nitrogênio total (ambos negativamente) no inverno. Esperávamos um decréscimo da densidade em direção ao norte (gradiente latitudinal) e aumento em condições lênticas (reservatórios). Apesar de a densidade máxima ter sido encontrada próximo do ponto de introdução (La Plata River) valores similares também foram observados 2.000 km ao norte (rio Paraguai). A primeira hipótese foi refutada. A segunda hipótese foi parcialmente aceita. Abundâncias foram consistentemente maiores no verão. Condições eutróficas e fluxo rápido parecem inibir o crescimento populacional. Recurso alimentar (clorofila a) local influenciou a variação temporal. Limnoperna fortunei está amplamente distribuído na bacia de La Plata, alcançando densidades larvais superiores a 10.000 ind. m-3 em todas as principais sub bacias. A espécie possui alta capacidade de dispersão intrínseca (larva planctônica livre), ampla tolerância aos fatores ambientais e os processos de dispersão são potencializados por processos naturais (e.g. deslocamento de fauna) e facilitação humana (e.g. navegação comercial).(AU)

Assuntos