Estrutura das comunidades de macroinvertebrados em corredeiras de um riacho cárstico Neotropical nas estações seca e chuvosa

AIM: Our study evaluated the effects of physical and chemical variables and seasonality on diversity and structure of the macroinvertebrate fauna in riffles of a Neotropical chalk stream; METHODS: Sampling was performed during the dry (September 2003) and rainy (March 2004) seasons, in five sites. Five samples were taken at each point with a Surber sampler. Physical and chemical variables were also evaluated; RESULTS: Temperature, pH, orthophosphate and total nitrogen were very similar for both seasons, while riffle length, conductivity, alkalinity, ammonia, phosphorus and leaf litter had different values. The total number of organisms collected was 25114 belonging to at least 50 families. Insects dominated in the samples. The highest abundance was found for the dry period. Temporary stretches were sampled in rainy season in order to complement the faunal inventory; CONCLUSIONS: The environmental seasonality was an important factor for structuring the macroinvertebrate fauna, with a significant difference between the invertebrate compositions in the sampling periods. The results of this study demonstrate the influences of seasonality on the temporal variation of communities.OBJETIVOS: Este estudo avaliou os efeitos das variáveis químicas e físicas e da sazonalidade na diversidade e estrutura da fauna de macroinvertebrados em corredeiras de um riacho cárstico Neotropical; MÉTODOS: As coletas foram realizadas durante as estações seca (Setembro 2003) e chuvosa (Março 2004), em cinco pontos de amostragem. Em cada ponto foram coletadas cinco unidades amostrais utilizando um amostrador Surber. Variáveis químicas e físicas também foram avaliadas; RESULTADOS: Temperatura, pH, ortofosfato e nitrogênio total foram muito similares entre as estações, enquanto os valores de comprimento da corredeira, condutividade, alcalinidade, amônia, fósforo total e a quantidade de folhiço variaram. O número total de organismos coletado foi 25114 pertencentes, a pelo menos, 50 famílias. Insetos constituíram o grupo dominante nas amostras. Trechos temporários foram amostrados na estação chuvosa, com o intuito de complementar o inventário faunístico; CONCLUSÕES: A sazonalidade ambiental foi um fator importante na estruturação da fauna de macroinvertebrados, onde uma diferença significativa entre a composição dos macroinvertebrados aquáticos nos períodos amostrados foi observada. Os resultados deste estudo demonstram a influência da sazonalidade na variação temporal da comunidade.Universidade Federal de Mato Grosso do Sul - Programa de Pós-Gradução em Tecnologias Ambientai

Análise das Mudanças da Cobertura do Solo de uma Área de Cerrado (Savana Tropical) no Centro-Oeste do Brasil

The objective of the present work was to carry out an analysis of the land cover of an area in the centre-west of Brazil, at two different times, in 1966 and 2001, using a satellite image and a topographic map, in the Geographic Information System (GIS) environment. The 1966 land cover map was obtained by vectorizing the SE-22-Y-A-V topographic map (IBGE), while the 2001 land cover map was obtained from supervised automatic classification of the Landsat image ETM+ satellite orbit/point 224/073 of August 2001. The analysis showed alterations from natural cover to anthropogenic. In 1966, natural cover was 90% or more (principally true cerrado and forest), while in 2001, natural cover had decreased to 24%, being replaced by arable land and primarily grassland.O objetivo do presente trabalho foi produzir uma análise multitemporal da cobertura do solo em uma área no centro-oeste do Brasil, em duas diferentes épocas, em 1966 e 2001, utilizando uma imagem de satélite e uma carta topográfica em ambiente SIG (Sistema de Informações Geográficas). A carta de cobertura do solo de 1966 foi obtida pela vetorialização da carta topográfica SE-22-Y-A-V (IBGE), enquanto que a carta de cobertura do solo de 2001 foi obtida através de uma classificação automática supervisionada da imagem do satélite Landsat 7 ETM+ órbita/ponto 224/073 de agosto de 2001. A análise mostrou as alterações da cobertura natural para antrópica. Em 1966, a cobertura natural representava 90% ou mais da área estudada (principalmente por cerrado sentido restrito e formações florestais), enquanto que em 2001, a cobertura natural havia diminuído para 24%, sendo substituída principalmente por áreas de agricultura e pasto

Anastrozole versus tamoxifen for the prevention of locoregional and contralateral breast cancer in postmenopausal women with locally excised ductal carcinoma in situ (IBIS-II DCIS): a double-blind, randomised controlled trial

Background Third-generation aromatase inhibitors are more effective than tamoxifen for preventing recurrence in postmenopausal women with hormone-receptor-positive invasive breast cancer. However, it is not known whether anastrozole is more effective than tamoxifen for women with hormone-receptor-positive ductal carcinoma in situ (DCIS). Here, we compare the efficacy of anastrozole with that of tamoxifen in postmenopausal women with hormone-receptor-positive DCIS. Methods In a double-blind, multicentre, randomised placebo-controlled trial, we recruited women who had been diagnosed with locally excised, hormone-receptor-positive DCIS. Eligible women were randomly assigned in a 1:1 ratio by central computer allocation to receive 1 mg oral anastrozole or 20 mg oral tamoxifen every day for 5 years. Randomisation was stratified by major centre or hub and was done in blocks (six, eight, or ten). All trial personnel, participants, and clinicians were masked to treatment allocation and only the trial statistician had access to treatment allocation. The primary endpoint was all recurrence, including recurrent DCIS and new contralateral tumours. All analyses were done on a modified intention-to-treat basis (in all women who were randomised and did not revoke consent for their data to be included) and proportional hazard models were used to compute hazard ratios and corresponding confidence intervals. This trial is registered at the ISRCTN registry, number ISRCTN37546358. Results Between March 3, 2003, and Feb 8, 2012, we enrolled 2980 postmenopausal women from 236 centres in 14 countries and randomly assigned them to receive anastrozole (1449 analysed) or tamoxifen (1489 analysed). Median follow-up was 7·2 years (IQR 5·6–8·9), and 144 breast cancer recurrences were recorded. We noted no statistically significant difference in overall recurrence (67 recurrences for anastrozole vs 77 for tamoxifen; HR 0·89 [95% CI 0·64–1·23]). The non-inferiority of anastrozole was established (upper 95% CI <1·25), but its superiority to tamoxifen was not (p=0·49). A total of 69 deaths were recorded (33 for anastrozole vs 36 for tamoxifen; HR 0·93 [95% CI 0·58–1·50], p=0·78), and no specific cause was more common in one group than the other. The number of women reporting any adverse event was similar between anastrozole (1323 women, 91%) and tamoxifen (1379 women, 93%); the side-effect profiles of the two drugs differed, with more fractures, musculoskeletal events, hypercholesterolaemia, and strokes with anastrozole and more muscle spasm, gynaecological cancers and symptoms, vasomotor symptoms, and deep vein thromboses with tamoxifen. Conclusions No clear efficacy differences were seen between the two treatments. Anastrozole offers another treatment option for postmenopausal women with hormone-receptor-positive DCIS, which may be be more appropriate for some women with contraindications for tamoxifen. Longer follow-up will be necessary to fully evaluate treatment differences

The impact of immediate breast reconstruction on the time to delivery of adjuvant therapy: the iBRA-2 study

Background: Immediate breast reconstruction (IBR) is routinely offered to improve quality-of-life for women requiring mastectomy, but there are concerns that more complex surgery may delay adjuvant oncological treatments and compromise long-term outcomes. High-quality evidence is lacking. The iBRA-2 study aimed to investigate the impact of IBR on time to adjuvant therapy. Methods: Consecutive women undergoing mastectomy ± IBR for breast cancer July–December, 2016 were included. Patient demographics, operative, oncological and complication data were collected. Time from last definitive cancer surgery to first adjuvant treatment for patients undergoing mastectomy ± IBR were compared and risk factors associated with delays explored. Results: A total of 2540 patients were recruited from 76 centres; 1008 (39.7%) underwent IBR (implant-only [n = 675, 26.6%]; pedicled flaps [n = 105,4.1%] and free-flaps [n = 228, 8.9%]). Complications requiring re-admission or re-operation were significantly more common in patients undergoing IBR than those receiving mastectomy. Adjuvant chemotherapy or radiotherapy was required by 1235 (48.6%) patients. No clinically significant differences were seen in time to adjuvant therapy between patient groups but major complications irrespective of surgery received were significantly associated with treatment delays. Conclusions: IBR does not result in clinically significant delays to adjuvant therapy, but post-operative complications are associated with treatment delays. Strategies to minimise complications, including careful patient selection, are required to improve outcomes for patients

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Occurrence of the freshwater jellyfish Craspedacusta sowerbii (Lankester, 1880) (Hydrozoa, Limnomedusae) in a calcareous lake in Mato Grosso do Sul, Brazil

The occurrence of the freshwater jellyfish Craspedacusta sowerbii (=sowerbyi) Lankester, 1880 was recorded in April 2006 in the Lagoa Misteriosa water body, a calcareous lake (doline) in Mato Grosso do Sul State, Brazil. Only Rotifera composed the zooplankton community was composed only of Rotifera and the environment was meso-eutrophic system. The nomenclature of C. sowerbii is discussed with regard to the use of the correct spelling and an alternative one. The distributions of C. sowerbii in Brazil include eight states and in South America the distribution includes four countries

Checklist of freshwater ostracods (Crustacea, Ostracoda) of the Pantanal of Mato Grosso do Sul, Brazil

Nowadays there are about 2,000 species of non-marine Ostracoda described in diverse aquatic environments in the world, of which 117 species from 37 genera are known in Brazil. The present survey of ostracods of the Pantanal of the state of Mato Grosso do Sul, recorded 35 species belonging to the families Cyprididae, Candonidae, Limnocytheridae and Darwinulidae. The ostracod fauna of Brazil is still poorly known and the ostracod biodiversity from several habitats (e.g. interstitial) remains unknown. In this sense, there is a great probability to find new records and new taxa of ostracods in the Pantanal, as well as throughout Brazil

Density and body size of the larval stages of the invasive golden mussel (Limnoperna fortunei) in two neotropical rivers Densidade e tamanho dos estágios larvais do molusco invasor mexilhão dourado (Limnoperna fortunei) em dois rios neotropicais

AIM: The present study involved an analysis of the monthly variations in the population densities and body sizes of the different stages of planktonic larvae of the invasive golden mussel (Limnoperna fortunei), in the rivers Paraguay and Miranda; METHODS: The study was carried out between February 2004 and January 2005. Monthly collection of the plankton samples was accompanied by physical, chemical and biological analyses of the water; RESULTS: The Miranda River presented higher values of calcium, pH, alkalinity, conductivity and total phosphorous. Larval density varied from 0-24 individuals.L-1 in the Paraguay River, with a peak in March of 2004, while in the Miranda River, densities varied between 0-9 individuals.L-1 with a peak in February of 2004. No larvae were encountered during the coldest months, May and June. No significant correlations were found between environmental variables and larval density in either river. Only the valved larval stages were recorded. The "D" and veliger forms were most abundant; umbonate larvae were rare in the Miranda River samples. Mean body sizes of "D", veliger and umbonate larval stages were, respectively, 111, 135 and 152 µm, in the Paraguay River, and 112, 134 and 154 µm in the Miranda River. Principal Components Analysis indicated positive relationships between "D" larval stage size and the ratio between inorganic and organic suspended solids, while negative relationships were found between larval size and calcium and chlorophyll-; CONCLUSIONS: The larvae were recorded in the plankton during most of the year, with the exception of the two colder months. Neither densities nor larval stage body sizes were significantly different between the two rivers. Possible positive effects of food and calcium concentrations on body size were not recorded. This species may be adapted to grow in environments with elevated sediment concentrations.OBJETIVO: O presente estudo analisou as variações mensais em densidades populacionais e tamanho dos diferentes estágios das larvas planctônicas do molusco invasor mexilhão dourado (Limnoperna fortunei), nos rios Paraguai e Miranda; MÉTODOS: O estudo foi realizado entre fevereiro de 2004 e janeiro de 2005. Amostras mensais de plâncton foram acompanhadas pela análise de características físicas, químicas e biológicas da água; RESULTADOS: O rio Miranda apresentou maiores valores de cálcio, pH, alcalinidade, condutividade e fósforo total. A densidade das larvas variou entre 0-24 indivíduos.L-1 no rio Paraguay, com o máximo em março de 2004, enquanto no rio Miranda, a densidade variou entre 0-9 indivíduos.L-1, com o máximo em fevereiro de 2004. Larvas não foram encontradas nos meses mais frios, maio e junho. Nenhuma correlação significativa foi encontrada entre as características ambientais e densidades das larvas. Somente larvas com valvas foram encontradas. As formas "D" e veliger foram mais abundantes; a forma umbonada foi rara no rio Miranda. Valores médios dos tamanhos dos estágios "D", veliger e umbonada foram, respectivamente, 111, 135 e 152 µm, no rio Paraguai, e 112, 134 e 154 µm no rio Miranda. A análise de Componentes Principais indicou relações positivas entre o comprimento da forma "D" e a relação sólidos suspensos inorgânicos:orgânicos, enquanto relações negativas foram indicadas entre o comprimento da forma "D" e concentrações de cálcio e clorofila-; CONCLUSÕES: As larvas foram encontradas no plâncton durante a maior parte do ano, com a exceção dos meses mais frios. A densidade de larvas e o tamanho foram similares nos dois rios. Não foram registrados efeitos positivos da disponibilidade de alimento ou da concentração de cálcio sobre o tamanho das larvas. Esta espécie pode ser adaptada a crescer em ambientes com altas concentrações de sedimentos