Using data from a private provider of telemedicine to assess the severity of the early 2021 Covid-19 wave in Brazil

In early 2021, Brazil saw a dramatic recurrence in Covid-19 cases associated to the spread of a novel variant of the SARS-CoV-2 virus, the P1 variant. In light of previous reports showing that this variant is more transmissible and more likely to infect people who had recovered from previous infection, a retrospective analysis was conducted to assess if the early 2021 Covid-19 wave in Brazil was associated with an increase in the number of individuals presenting with a more severe clinical course. Fifty-one thousand and fourteen individuals who underwent telemedicine consultations were divided into two groups: patients seen on or before January 31, 2021, and on or after February 1, 2021. These dates were chosen based on the spread of the P1 variant in Brazil. Referral to the emergency department (ED) was used as a marker of a more severe course of the disease. No differences were seen in the proportion of patients referred to the ED in each group nor in the odds ratio of being referred to the ED from the 1st of February 2021 (OR=0.909; 95%CI: 0.81-1.01). Considering the entire cohort, age had an impact on the odds of being referred to the ED, with individuals older than 59 years showing twice the risk of the remaining population and those less than 19 years showing a lower risk.

Reproductive traits in different Nile tilapia genetic groups / [Características reprodutivas em diferentes grupos genéticos de tilápia do Nilo]

The aim of this study was to evaluate the reproductive traits of the non-inbred and inbred AquaAmérica, GIFT and AquaAmérica × GIFTgenetic groups. Six fish from each genetic group were used (2 females:1 male). Females were examined for the presence of eggs in their mouth at every four days, for 12 weeks. Reproduction occurred in all genetic groups (GIFT: 100%; non-inbred AquaAmérica and AquaAmérica ×GIFT: 75%; inbred AquaAmérica: 50%). Female weight, female standard length, total spawning weight, absolute fecundity, relative fecundity, spawn index and hatching rate did not differ significantly between the genetic groups. However, the non-inbred AquaAmérica variety showed lower values (P<0.05) for egg diameter (2.4mm) and egg weight (4.2mg) and higher values (P<0.05) for relative number of eggs (247.6 eggs/g of egg) than GIFT (egg diameter: 2.8mm; egg weight: 5.7mg; relative number of eggs: 175.4 eggs/g of egg) and AquaAmérica ×GIFT (egg diameter: 2.8mm; egg weight: 5.9mg; relative number of eggs: 168.8 eggs/g of egg). In conclusion, the non-inbred AquaAmérica variety produces smaller, lighter eggs but a higher relative number of eggs than the GIFT variety and the AquaAmérica ×GIFT cross; and inbreeding negatively affects spawning rate.(AU)

O objetivo deste estudo foi avaliar as características reprodutivas dos grupos genéticos AquaAmérica não endogâmicos e endogâmicos, GIFT e AquaAmérica × GIFT. Foram utilizados seis peixes de cada grupo genético (duas fêmeas:um macho). As fêmeas foram examinadas quanto à presença de ovos na boca a cada quatro dias, durante 12 semanas. A reprodução ocorreu em todos os grupos genéticos (GIFT: 100%; AquaAmérica não endogâmica e AquaAmérica × GIFT: 75%; AquaAmérica endogâmica: 50%). Peso e comprimento padrão de fêmea, peso total de desova, fecundidade absoluta, fecundidade relativa, índice de desova e taxa de eclosão não diferiram significativamente entre os grupos genéticos. Entretanto, a variedade não endogâmica da AquaAmérica apresentou valores mais baixos (P<0,05) para diâmetro do ovo (2,4mm) e peso do ovo (4,2mg) e maiores valores (P<0,05) para número relativo de ovos (247,6 ovos/g de ovo ) que GIFT (diâmetro do ovo: 2,8mm; peso do ovo: 5,7mg; número relativo de ovos: 175,4 ovos/g de ovo) e AquaAmérica × GIFT (diâmetro do ovo: 2,8mm; peso do ovo: 5,9mg; número relativo de ovos: 168,8 ovos/g de ovo). Em conclusão, a variedade AquaAmérica não endogâmica produz ovos menores e mais leves, mas um número relativo maior de ovos que a variedade GIFT e o cruzamento AquaAmérica × GIFT; a consanguinidade afeta negativamente a taxa de desova.(AU)

Perfil metabólico de filhotes de peixe-boi da Amazônia (Trichechus inunguis) em cativeiro, alimentados com diferentes sucedâneos do leite materno / [Metabolic profile of captive Amazonian manatee calves (Trichechus inunguis), fed different substitutes for maternal milk]

Dez filhotes de peixe-boi da Amazônia criados em cativeiro foram amamentados com diferentes dietas lácteas em duas etapas. Na primeira, com sucedâneo 1 (S1), utilizado rotineiramente no Inpa e, na segunda, com sucedâneo 2 (S2), elaborado com base na composição centesimal do leite materno da espécie. Cada etapa durou 62 dias, realizando-se coleta de sangue ao final de cada uma para avaliação dos valores de proteínas totais (PT), albumina (ALB), globulinas (GLO), glicose (GLI), lipídeos totais (LT), colesterol (COL), triglicerídeos (TRI), cálcio (Ca), fósforo (P), magnésio (Mg), sódio (Na), potássio (K), hematócrito (Ht) e hemoglobina (Hb). Houve redução dos níveis séricos de PT, ALB, GLO, Ca, P, K, GLI, LT, COL e TRI, após a alimentação dos animais com S2 quando comparados aos valores obtidos com S1. Os níveis de Na foram maiores quando administrado o S2 (143,47±0,99mmol/L). Valores de Ht e Mg não diferiram entre os tratamentos. O perfil metabólico, em geral, esteve dentro dos níveis normais para a espécie.(AU)

Ten Amazonian manatee calves who live in captivity were fed with different substitutes for maternal milk in two phases. During the first phase, the calves were fed substitute 1 (S1), which is what was routinely used by INPA, and during the second phase they were fed substitute 2 (S2), which was formulated based on the nutritional composition of T. inunguis maternal milk. Each phase lasted 62 days, when blood samples were collected for analysis of values of total protein (PT), albumin (ALB), globulin (GLO), glucose (GLI), total lipids (LT), cholesterol (COL), triglycerides (TRI), calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na), potassium (K), hematocrit (Ht) and hemoglobin (Hb). There was a decrease in PT, ALB, GLO, Ca, P and K after feeding the animals with S2 when compared to values obtained with S1. Sodium levels were higher when S2 was administered (148.16±1.15mmol/L) than when S1 was given (143.47±0.99 mmol/l). Values of Ht and Mg did not differ between treatments. The metabolic profile was within normal levels for this species.(AU)

Effects of nanoparticles of hydroxy-aluminum phthalocyanine on markers of liver injury and glucose metabolism in diabetic mice

Photodynamic therapy, by reducing pain and inflammation and promoting the proliferation of healthy cells, can be used to treat recurrent lesions, such as diabetic foot ulcers. Studies using the photosensitizer phthalocyanine, together with the nanostructured copolymeric matrix of Pluronic® and Carbopol® for the treatment of diabetic foot ulcers and leishmaniosis lesions, are showing promising outcomes. Despite their topical or subcutaneous administration, these molecules are absorbed and their systemic effects are unknown. Therefore, we investigated the effect of the subcutaneous administration of the hydroxy-aluminum phthalocyanine hydrogel without illumination on systemic parameters, markers of liver injury, and liver energy metabolism in type 1 diabetic Swiss mice. Both the hydrogel and the different doses of phthalocyanine changed the levels of injury markers and the liver glucose release, sometimes aggravating the alterations caused by the diabetic condition itself. However, the dose of 2.23 µg/mL caused less marked plasmatic and metabolic changes and did not change glucose tolerance or insulin sensitivity of the diabetic mice. These results are indicative that the use of hydroxy-aluminum phthalocyanine hydrogel for the treatment of cutaneous ulcers in diabetic patients is systemically safe.

Carcinoma papilar de tiroides no captante de radioyodo (I131): a propósito de un caso / Papillary thyroid carcinoma not collecting radioiodine (I131): presentation of a case

RESUMEN El carcinoma papilar de tiroides (CPT) corresponde a una neoplasia frecuente en el mundo y en nuestro país. Generalmente se asocia a buen pronóstico y altas tasas de sobrevida, gracias a características propias del tumor, precisas herramientas diagnósticas y terapias eficaces. Formas infrecuentes de CPT suelen tener comportamientos más agresivos y respuestas parciales a tratamientos habituales, tales como el CPT no captante de radioyodo (5% de los casos). Poca literatura existe respecto a este último y a su manejo. Diversas opciones de tratamiento han sido propuestas, según si hay evidencia de tejido tumoral, como el uso empírico de I131, cirugía, radioterapia, embolización e inhibidores de tirosina kinasa, sin embargo, sigue habiendo una respuesta incierta.

ABSTRACT Papillary thyroid carcinoma (PTC) is a common cancer in the world and in our country. It is usually associated with good prognosis and high survival rates, due to the tumor's characteristics, precise diagnostic tools and effective therapies. Unusual varieties of PTC have more aggressive behaviors and partial responses to usual treatments, such as negative uptake to radioiodine PTC (5% of cases). There is few literature about this variety and its treatment. Diverse treatment options have been proposed, according to whether there is evidence of tumor tissue, such as the empirical use of I131, surgery, radiotherapy, embolization and inhibitors of thyrosine kinase, however an uncertain response remains.

Tiller density and tillering on Brachiaria brizantha cv. Marandu pastures inoculated with Azospirillum brasilense / Densidade populacional e perfilhamento em pastagens de Brachiaria brizantha cv. Marandu inoculada com Azospirillum brasilense

The objective of this study is to verify the population density and the dynamics of tillering in the Marandu palisade grass sward subjected to nitrogen (N) fertilization strategies, characterized by the N supply via urea or bacterial inoculant (Azospirillum brasilense). The treatments comprised of four nitrogen fertilization strategies: (A) Without fertilization, (B) 80 kg N/ha, (C) inoculant (A. brasilense), and (D) 80 kg N/ha + inoculant, distributed in a randomized complete block design, with three replications. The nitrogen supply strategies were evaluated during six periods: October, November, and December (2012) as well as January, March, and April (2013). The nitrogen dose or inoculant had no effect on the tiller appearance rate (TAR), tiller mortality rate (TMR), tiller survival rate (TSR), or tiller population density (TPD). However, these variables were influenced by the season. The TAR and TSR were higher at the beginning of the experimental period (October) and lower towards the end of the period (March-April), whereas, TMR and TPD exhibited the opposite behavior, with lower values in October and higher from January onward. Neither the nitrogen nor the inoculant influenced the population dynamics of the tillers in Marandu palisade grass.(AU)

Objetivou-se com este estudo verificar a densidade populacional e a dinâmica do perfilhamento em dosséis de capim Marandu submetidos a estratégias de adubação nitrogenada, caracterizadas pelo fornecimento de N via ureia ou inoculante (Azospirillum brasilense). Os tratamentos foram quatro estratégias de adubação nitrogenada: sem fertilização, 80kg N/ha, inoculante (A. brasilense) e 80kg N/ha + inoculante, distribuídos em um delineamento de blocos completos ao acaso, com três repetições por tratamento. As estratégias de aporte nitrogenado foram avaliadas em seis épocas: outubro, novembro e dezembro de 2012; e janeiro, março e abril de 2013. Não foi verificada influência da dose de nitrogênio ou do inoculante sobre a taxa de aparecimento (TAP), a taxa de mortalidade (TMP), a taxa de sobrevivência (TSP) e a densidade populacional de perfilhos (DPP). No entanto, essas variáveis foram influenciadas pela época do ano. A TAP e a TSP apresentaram maiores valores no início do período experimental (outubro) e menor valor ao final do período (março a abril). A TMP e a DPP expressaram respostas opostas, com menores valores em outubro e maiores a partir de janeiro. Não houve influência do nitrogênio e do inoculante sobre a dinâmica populacional de perfilhos em capim Marandu.(AU)

Methods for selection of Daphnia resting eggs: the influence of manual decapsulation and sodium hypoclorite solution on hatching rates / Técnicas para seleção de ovos de resistência de Daphnia: influência do desencapsulamento manual e imersão em solução de hipoclorito nas taxas de eclosão

Abstract Cladocerans are able to produce resting eggs inside a protective resistant capsule, the ephippium, that difficults the visualization of the resting eggs, because of the dark pigmentation. Therefore, before hatching experiments, methods to verify viable resting eggs in ephippia must be considered. This study aimed to evaluate the number of eggs per ephippium of Daphnia from two tropical aquatic ecosystems and the efficiency of some methods for decapsulating resting eggs. To evaluate the influence of methods on hatching rates, three different conditions were tested: immersion in sodium hypochlorite, manually decapsulated resting eggs and intact ephippia. The immersion in hypochlorite solution could evaluate differences in numbers of resting eggs per ephippium between the ecosystems studied. The exposure to sodium hypochlorite at a concentration of 2% for 20 minutes was the most efficient method for visual evaluation and isolation of the resting eggs. Hatching rate experiments with resting eggs not isolated from ephippia were underestimated (11.1 ± 5.0%), showing the need of methods to quantify and isolate viable eggs. There were no differences between the hatching rate of resting eggs submitted to hypochlorite solution (47.2 ± 7.34%) and manually decapsulated (53.7 ± 13.24%). However, the immersion in hypochlorite was a more efficient technique, faster and not requiring manual ability.

Resumo Cladóceros são capazes de produzir ovos de resistência envoltos por uma cápsula protetora, o efípio, que dificulta a visualização do número de ovos, devido à pigmentação escura. Assim, antes da condução de experimentos de eclosão, métodos para determinar o número de ovos de resistência viáveis no interior do efípio devem ser utilizados. Este estudo teve como objetivo avaliar o número de ovos por efípio de Daphnia de dois ecossistemas aquáticos tropicais e a eficiência de alguns métodos de desencapsulamento de ovos de resistência. Para avaliar a influência dos métodos na taxa de eclosão foram testadas três condições: imersão em hipoclorito de sódio, ovos de resistência desencapsulados manualmente e efípios intactos. A imersão em solução de hipoclorito permitiu avaliar as diferenças no número de ovos de resistência por efípios entre os ecossistemas. A exposição ao hipoclorito de sódio a uma concentração de 2% durante 20 minutos foi o método mais eficiente para a avaliação visual e isolamento dos ovos de resistência. A taxa de eclosão de ovos não isolados de efípios foi subestimada (11,1 ± 5,0%), mostrando a necessidade de métodos para quantificação e isolamento dos ovos. Não foi verificada diferença de eclosão entre os ovos isolados a partir da imersão em solução de hipoclorito (47,2 ± 7,34%) e manualmente desencapsulados (53,7 ± 13,24%). Entretanto, a imersão em hipoclorito é uma técnica mais eficiente, pois além de mais rápida, não necessita de destreza manual.

Traditional knowledge and uses of the Caryocar brasiliense Cambess. (Pequi) by “quilombolas” of Minas Gerais, Brazil: subsidies for sustainable management / Conhecimento tradicional e usos de Caryocar brasiliense Cambess. (Pequi) por quilombolas de Minas Gerais, Brasil: subsídios para o manejo sustentável

Abstract Local knowledge of biodiversity has been applied in support of research focused on utilizing and management of natural resources and promotion of conservation. Among these resources, Pequi (Caryocar brasiliense Cambess.) is important as a source of income and food for communities living in the Cerrado biome. In Pontinha, a “quilombola” community, which is located in the central region of State of Minas Gerais, Brazil, an ethnoecological study about Pequi was conducted to support initiatives for generating income for this community. Data were collected through semi-structured interviews, participant observation, and crossing. The most relevant uses of Pequi were family food (97%), soap production (67%), oil production (37%), medical treatments (17%), and trade (3%). Bees were the floral visitors with the highest Salience Index (S=0.639). Among frugivores that feed on unfallen fruits, birds showed a higher Salience (S=0.359) and among frugivores who use fallen fruits insects were the most important (S=0.574). Borers (folivorous caterpillars) that attack trunks and roots were the most common pests cited. According to the respondents, young individuals of Pequi are the most affected by fire due to their smaller size and thinner bark. Recognition of the cultural and ecological importance of Pequi has mobilized the community, which has shown interest in incorporating this species as an alternative source of income.

Resumo O conhecimento local acerca da biodiversidade vem sendo utilizado em pesquisas voltadas ao uso e manejo de recursos naturais aliados à conservação. Entre estes recursos, destaca-se o Pequi (Caryocar brasiliense Cambess.) devido à sua importância econômica e alimentar para comunidades que vivem no Cerrado. No quilombo de Pontinha, localizado na região central do estado de Minas Gerais, um estudo etnoecológico sobre o Pequi foi desenvolvido, a fim de subsidiar iniciativas de geração de trabalho e renda para esta comunidade. Informações foram obtidas por meio de entrevistas semiestruturadas, observação participante e travessia. Alimentação familiar (97%), produção de sabão (67%), produção de óleo (37%), tratamento medicinal (17%) e comércio (3%) foram os principais usos do Pequi citados pelos comunitários. Abelhas foram os visitantes florais com maior Índice de Saliência (S=0,639). Dentre os frugívoros que se alimentam de frutos não caídos, as aves apresentaram maior Saliência (S=0,359) e os insetos foram os mais importantes frugívoros entre os que utilizam frutos caídos (S=0,574). Brocas, lagartas folívoras e que atacam troncos e raízes foram as pragas mais citadas. Os indivíduos jovens de Pequi são, segundo os entrevistados, os mais afetados pelo fogo devido ao menor porte e por ter a casca menos espessa. O reconhecimento da importância cultural e ecológica do Pequi tem mobilizado a comunidade, que demonstra interesse em fazer dessa espécie uma alternativa de renda.

Loss of biodiversity in a conservation unit of the Brazilian Atlantic Forest: the effect of introducing non-native fish species / Perda de biodiversidade em uma unidade de conservação da Mata Atlântica brasileira: efeitos da introdução de espécies não nativas de peixes

Abstract The introduction of species has become an important problem for biodiversity and natural ecosystem conservation. The lake system of the middle Rio Doce (MG, Brazil) comprises c. 200 lakes at various conservation states, of which 50 are located within the Rio Doce State Park (PERD). Previous studies had verified several of these lakes suffered non-native fishes introductions and the presence of these species needs for the implementation of actions aiming at not only their control but also the preservation of the native species. This study discusses the effects of non-native fish species in the largest conservation unit of Atlantic Forest in Minas Gerais, southeast of Brazil, using data from 1983 to 2010 distributed as follow: data prior to 2006 were obtained from previous studies, and data from September 2006 to July 2010 were obtained in Lake Carioca at four sampling stations using gillnets, seine nets and sieve. A total of 17 fish species was collected (2006-2010) of which five were introduced species. Among the small to medium size native species (30 to 2000 mm standard length) seven had disappeared, two are new records and one was recaptured. The non-native species Cichla kelberi (peacock bass) and Pygocentrus nattereri (red piranha) are within the most abundant captured species. Integrated with other actions, such as those preventing new introductions, a selective fishing schedule is proposed as an alternative approach to improve the conservation management actions and the local and regional biodiversity maintenance.

Resumo A introdução de espécies tornou-se um importante problema para a conservação da biodiversidade e dos ecossistemas naturais. O sistema de lagos do médio Rio Doce (MG, Brasil) compreende cerca de 200 lagos em vários estados de conservação, dos quais 50 estão localizados dentro do Parque Estadual do Rio Doce (PERD). Estudos anteriores demonstraram que vários desses lagos sofreram introduções de peixes não nativos. Este estudo discute os efeitos das espécies de peixes não nativos na maior unidade de conservação da Mata Atlântica em Minas Gerais, sudeste do Brasil, utilizando dados de 1983 até 2010, distribuídos da seguinte forma: dados de 1983 a 2005 obtidos de estudos realizados anteriormente, e dados de setembro de 2006 a julho de 2010 obtidos no lago Carioca, utilizando redes de emalhar, redes de arrasto e peneira. Um total de 17 espécies de peixes foi coletado (2006-2010), sendo cinco introduzidas. Dentre estas, Cichla kelberi (tucunaré) e Pygocentrus nattereri (piranha vermelha) estiveram dentre as mais abundantes. Entre as espécies nativas de pequeno a médio porte (30-2000 mm de comprimento padrão), duas foram novos registros e uma foi recapturada. O desaparecimento de sete destas espécies, registradas em estudos anteriores, e a baixa representatividade nas amostragens da maioria das espécies remanescentes, evidencia o alto impacto da invasão de peixes na comunidade estudada. Considerando a importância de ações de manejo de espécies não nativas visando à conservação e manutenção da biodiversidade local e regional, propõem-se a realização de pescas seletivas intensivas, juntamente com ações que previnam novas introduções, incluindo ações educativas junto às comunidades locais.

Characterization of diversity and genetic structure in natural populations of Stryphnodendron adstringens (Mart. ) Coville by means of allozyme markers

O S. adstringens, árvore típica do Cerrado, tem sido explorada visando suas propriedades medicinais e tanantes. Em razão do ainda incipiente conhecimento genético da espécie, este trabalho teve como objetivo caracterizar a diversidade e a estrutura genética de S. adstringens por meio de marcadores aloenzimáticos. Foram coletadas sementes em cinco mesorregiões brasileiras, sendo amostrados 627 indivíduos divididos em 16 populações localizadas nos Estados de Minas Gerais e Goiás. Foram testados 14 sistemas isoenzimáticos; destes, sete foram polimórficos com o total de 10 locos e 28 alelos. O valor de diversidade genética média (H) foi 0,226, a proporção média de locos polimórficos (P) foi 68,75, o número médio de alelos por loco polimórfico (AP) foi 2,65 e o número efetivo de alelos (Ae) foi igual a 1,29. Resultados do índice de fixação total (F= 0,003), do índice de fixação dentro de populações (f = -0,114) e, da medida de diferenciação genética (θ =0,105) foram não significativos, indicando a inexistência de estruturação genética. Na análise de agrupamento (UPGMA) foram observados dois grupos principais, o primeiro formado pela população do Parque Estadual (PE) do Rio Preto (MG), e outro, formado pelas demais populações. Se excluída a população do PE do Rio Preto das análises, G ST é drasticamente reduzido de 0,077 para 0,026. Assim, aproximadamente 2/3 do valor total de G ST verificado em S. adstringens foi devido à variação entre a população do PE do Rio Preto e as demais populações. De modo geral, os valores H e P observados em S. adstringens são compatíveis aos constatados em árvores tropicais comumente distribuídas. Por outro lado, excluindo a população do PE do Rio Preto, o valor da medida de diferenciação genética G ST foi menor que o verificado em árvores tropicais nativas e pinheiros de zonas temperadas. A semelhança entre populações avaliadas indica que o fluxo gênico ainda é alto o suficiente para prevenir a diferenciação genética, pelo menos em nível local.

The S. adstringens, a typical Cerrado (Brazilian savannah) tree, is used because of its medicinal and tanning properties. Because of the still incipient genetic knowledge of the species, the objective of this work was to characterize the diversity and genetic structure of S. adstringens by using allozyme markers. Seeds were collected in five Brazilian mesoregions, in which 627 individuals in 16 populations in the states of Minas Gerais and Goiás were sampled. Fourteen isoenzyme systems were assessed, out of which seven were polymorphic with a total of 10 loci and 28 alleles. Average genetic diversity (H) was 0.226, average proportion of polymorphic loci (P) was 68.75, average number of alleles per polymorphic locus (AP) was 2.65 and effective number of alleles (Ae) was equal to 1.29. The results of total fixation index (F= 0.003), within population fixation index (f =-0.114) and genetic differentiation measure (θ =0.105) were not significant, which shows the inexistence of genetic structure. Two principal groups were found in the cluster analysis (UPGMA), where the first one was formed by the population of State Park (PE) of Rio Preto (MG) and the other, by the other populations. If the population of PE of Rio Preto is excluded from the analysis, G ST is drastically reduced from 0.077 to 0.026. Thus, approximately 2/3 of the total value of G ST found in S. adstringens was due to the variation among the population of PE of Rio Preto and the other populations. Overall, the values of H and P found in S. adstringens are compatible with the ones found in typically distributed tropical trees. On the other hand, by excluding the population of PE of Rio Preto, the value of the G ST genetic differentiation measure was smaller than the one found in native tropical trees from temperate zones. The similarity between the assessed populations shows that the gene flow is still high enough to avoid genetic differentiation, at the local level, at least.

Utility of a novel risk score for prediction of ventricular tachycardia and cardiac death in chronic Chagas disease - the SEARCH-RIO study

The SEARCH-RIO study prospectively investigated electrocardiogram (ECG)-derived variables in chronic Chagas disease (CCD) as predictors of cardiac death and new onset ventricular tachycardia (VT). Cardiac arrhythmia is a major cause of death in CCD, and electrical markers may play a significant role in risk stratification. One hundred clinically stable outpatients with CCD were enrolled in this study. They initially underwent a 12-lead resting ECG, signal-averaged ECG, and 24-h ambulatory ECG. Abnormal Q-waves, filtered QRS duration, intraventricular electrical transients (IVET), 24-h standard deviation of normal RR intervals (SDNN), and VT were assessed. Echocardiograms assessed left ventricular ejection fraction. Predictors of cardiac death and new onset VT were identified in a Cox proportional hazard model. During a mean follow-up of 95.3 months, 36 patients had adverse events: 22 new onset VT (mean±SD, 18.4±4‰/year) and 20 deaths (26.4±1.8‰/year). In multivariate analysis, only Q-wave (hazard ratio, HR=6.7; P<0.001), VT (HR=5.3; P<0.001), SDNN<100 ms (HR=4.0; P=0.006), and IVET+ (HR=3.0; P=0.04) were independent predictors of the composite endpoint of cardiac death and new onset VT. A prognostic score was developed by weighting points proportional to beta coefficients and summing-up: Q-wave=2; VT=2; SDNN<100 ms=1; IVET+=1. Receiver operating characteristic curve analysis optimized the cutoff value at >1. In 10,000 bootstraps, the C-statistic of this novel score was non-inferior to a previously validated (Rassi) score (0.89±0.03 and 0.80±0.05, respectively; test for non-inferiority: P<0.001). In CCD, surface ECG-derived variables are predictors of cardiac death and new onset VT.

Dynamics of chest wall volume regulation during constant work rate exercise in patients with chronic obstructive pulmonary disease

This study evaluated the dynamic behavior of total and compartmental chest wall volumes [(V CW) = rib cage (V RC) + abdomen (V AB)] as measured breath-by-breath by optoelectronic plethysmography during constant-load exercise in patients with stable chronic obstructive pulmonary disease. Thirty males (GOLD stages II-III) underwent a cardiopulmonary exercise test to the limit of tolerance (Tlim) at 75% of peak work rate on an electronically braked cycle ergometer. Exercise-induced dynamic hyperinflation was considered to be present when end-expiratory (EE) V CW increased in relation to resting values. There was a noticeable heterogeneity in the patterns of V CW regulation as EEV CW increased non-linearly in 17/30 "hyperinflators" and decreased in 13/30 "non-hyperinflators" (P < 0.05). EEV AB decreased slightly in 8 of the "hyperinflators", thereby reducing and slowing the rate of increase in end-inspiratory (EI) V CW (P < 0.05). In contrast, decreases in EEV CW in the "non-hyperinflators" were due to the combination of stable EEV RC with marked reductions in EEV AB. These patients showed lower EIV CW and end-exercise dyspnea scores but longer Tlim than their counterparts (P < 0.05). Dyspnea increased and Tlim decreased non-linearly with a faster rate of increase in EIV CW regardless of the presence or absence of dynamic hyperinflation (P < 0.001). However, no significant between-group differences were observed in metabolic, pulmonary gas exchange and cardiovascular responses to exercise. Chest wall volumes are continuously regulated during exercise in order to postpone (or even avoid) their migration to higher operating volumes in patients with COPD, a dynamic process that is strongly dependent on the behavior of the abdominal compartment.

Fluctuations of the population of Daphnia laevis Birge 1878: a six-year study in a tropical lake / Flutuações da população de Daphnia laevis Birge 1878: seis anos de estudo em um lago tropical

The fluctuation of the population of Daphnia laevis in Lake Jacaré (Middle River Doce, Minas Gerais) was monitored monthly (at one point in the limnetic region) for six years (2002-2007) as part of the Program of Long-Term Ecological Research (LTER/UFMG). The following parameters were also monitored: water temperature, pH, electrical conductivity, dissolved oxygen, chlorophyll a, total phosphorus, phosphate, total nitrogen, nitrate, nitrite, ammonia, and densities of Chaoborus and ephippia of Daphnia laevis in the sediment. A seasonal pattern was observed in the fluctuation of D. laevis, with higher densities recorded during periods of circulation (May-August). A significant correlation was found between the density of D. laevis and temperature (r = -0.47, p = 0.0001), chlorophyll-a (r = -0.32, p = 0.016) and indicators of the lake's trophic status (total phosphorus, r = 0.32, p = 0.007 and trophic state, r = 0.36, p = 0.003), as well as Chaoborus density (r = 0.43 and p = 0.002). These results indicate that changes in the physical and chemical characteristics of the water related with stratification and circulation of the lake may have a direct (temperature, total phosphorous) or an indirect (food availability, presence of predators, ephippia eclosion) influence on the fluctuation of the D. laevis population.

A flutuação da população de Daphnia laevis na Lagoa Jacaré (Médio Rio Doce, Minas Gerais) foi monitorada mensalmente, em um ponto na região limnética, por seis anos (2002 a 2007), como parte do Programa de Pesquisas Ecológicas de Longa Duração (PELD/UFMG). Os seguintes parâmetros foram monitorados: temperatura da água, pH, condutividade elétrica, oxigênio dissolvido, clorofila-a , fósforo total, fosfato, nitrogênio total, nitrato, nitrito, amônia e densidades de Chaoborus e de efípios de Daphnia laevis no sedimento. Um padrão sazonal foi observado na flutuação de D. laevis, com maiores densidades registradas durante períodos de circulação (maio a agosto). Correlações significativas foram observadas entre a densidade de D. laevis e a temperatura (r = -0.47, p = 0.0001) e a clorofila-a (r = -0.32, p = 0.016), e indicadores do estado trófico do lago (fósforo total, r = 0.32, p = 0.007 e estado trófico, r = 0.36, p = 0.003), além de densidade de Chaoborus (r = 0.43, p = 0.002). Esses resultados indicam que mudanças nas características físicas e químicas da água relacionadas com os periodos de estratificação e circulação do lago podem influenciar diretamente (temperatura, fósforo total) ou indiretamente (disponibilidade de alimento, presença de predadores, eclosão de efípios) a flutuação da população de D. laevis.

Markers of insulin resistance and sedentary lifestyle are predictors of preeclampsia in women with adverse obstetric results

Some thrombophilias and severe preeclampsia may increase the risk for preterm deliveries and fetal death due to placental insufficiency. Our objective was to evaluate clinical and laboratory data as predictors of preeclampsia in a population of mothers with 3rd trimester fetal losses or preterm deliveries. In a longitudinal retrospective study, 54 consecutive women (age range: 16 to 39 years) with normotensive pregnancies were compared to 79 consecutive women with preeclampsia (age range: 16 to 43 years). Weight accrual rate (WAR) was arbitrarily defined as weight gain from age 18 years to the beginning of pregnancy divided by elapsed years. Independent predictors of preeclampsia were past history of oligomenorrhea, WAR >0.8 kg/years, pre-pregnancy or 1st trimester triglyceridemia >150 mg/dL, and elevated acanthosis nigricans in the neck. In a multivariate logistic regression model, two or more predictors conferred an odds ratio of 15 (95 percentCI [5.9-37]; P < 0.001) to develop preeclampsia (85 percent specificity, 73 percent sensitivity, c-statistic of 81 ± 4 percent; P < 0.0001). Clinical markers related to insulin resistance and sedentary lifestyles are strong independent predictors of preeclampsia in mothers with 3rd trimester fetal losses or preterm deliveries due to placental insufficiency. Women at risk for preeclampsia in this particular population might benefit from measures focused on overcoming insulin resistance.

Purification and biological effects of a C-type lectin isolated from bothrops moojeni

Snake venom proteins from the C-type lectin family have very distinct biological activities despite their highly conserved primary structure, which is homologous to the carbohydrate recognition region of true C-type lectins. We purified a lectin-like protein (BmLec) from Bothrops moojeni venom and investigated its effect on platelet aggregation, insulin secretion, antibacterial activity, and isolated kidney cells. The BmLec was purified using two chromatographic steps: affinity chromatography and reverse phase high performance liquid chromatography (HPLC). BmLec showed a dose-dependent platelet aggregation and significantly decreased the bacterial growth rate in approximately 15 percent. During scanning electron microscopy, the profile of Xanthomonas axonopodis pv. passiflorae treated with lectin disclosed a high vesiculation and membrane rupture. BmLec induced a strong and significant increase in insulin secretion at 2.8 and 16.7 mM glucose concentrations, and this effect was seen in the presence of EGTA in both experiments. BmLec (10 µg/mL) increased the perfusion pressure, renal vascular resistance and urinary flow. The glomerular filtration rate and percentages of sodium, potassium and chloride tubular transport were reduced at 60 minutes of perfusion. Renal alterations caused by BmLec were completely inhibited by indomethacin in all evaluated parameters. In conclusion, the C-type lectin isolated from Bothrops moojeni affected platelet aggregation, insulin secretion, antibacterial activity and isolated kidney function.

Circadian cardiac autonomic function in perinatally HIV-infected preschool children

The 24-h heart rate variability and QT-interval adaptation was investigated in perinatally HIV-infected preschool children classified according to immunological status in order to assess autonomic function at early stages of infection. Thirty-five perinatally HIV-infected and clinically stable children (4.8 ± 0.3 years) were enrolled after approval of the study by the University Hospital Pedro Ernesto Ethics Committee and written informed parental consent was obtained. The children were classified according to peripheral CD4+ count (cells/µL) as follows: group 1, N = 11 (≥1000); group 2, N = 7 (≥500 and <1000); group 3, N = 17 (<500). Left ventricular ejection fraction (>55%), 24-h RR interval variability (RRV) indexes (NN, SDANN, SDNN index, r-MSSD) and 24-h QT and Bazett-corrected QT (QTc) were determined, and groups were matched for age, body surface area, and left ventricular ejection fraction, reducing biases in RRV. The peak differences (∆) between the highest and lowest RRV and QT indexes were extracted from nocturnal (1 am-6 am) and daytime (1 pm-6 pm) hourly assessed segments, respectively. Pearson’s correlation (r) and Kruskal-Wallis ANOVA were used to compare groups. CD4+ count correlated positively with ∆NN (r = 0.45; P = 0.003). There were no significant differences in daytime NN among groups. Nighttime SDNN index (P = 0.01), nighttime r-MSSD (P = 0.003), ∆NN (P = 0.01), ∆SDNN index (P = 0.03) and ∆r-MSSD (P = 0.004) were significantly lower in group 3 than in the other groups. Expected nighttime QTc-interval lengthening was not observed in all groups. In perinatally HIV-infected preschool children with preserved left ventricular systolic function, parasympathetic-mediated autonomic dysfunction parallels immune status, impairing both RRV and circadian QTc interval adaptation.

Mechanical cardiac remodeling and new-onset atrial fibrillation in long-term follow-up of subjects with chronic Chagas' disease

Atrial fibrillation (AF) affects subjects with Chagas' disease and is an indicator of poor prognosis. We investigated clinical, echocardiographic and electrocardiographic variables of Chagas' disease in a long-term longitudinal study as predictors of a new-onset AF episode lasting >24 h, nonfatal embolic stroke and cardiac death. Fifty adult outpatients (34 to 74 years old, 62 percent females) staged according to the Los Andes classification were enrolled. During a follow-up of (mean ± SD) 84.2 ± 39.0 months, 9 subjects developed AF (incidence: 3.3 ± 1.0 percent/year), 5 had nonfatal stroke (incidence: 1.3 ± 1.0 percent/year), and nine died (mortality rate: 2.3 ± 0.8 percent/year). The progression rate of left ventricular mass and left ventricular ejection fraction was significantly greater in subjects who experienced AF (16.4 ± 20.0 g/year and -8.6 ± 7.6 percent/year, respectively) than in those who did not (8.2 ± 8.4 g/year; P = 0.03, and -3.0 ± 2.5 percent/year; P = 0.04, respectively). In univariate analysis, left atrial diameter ≥3.2 cm (P = 0.002), pulmonary arterial hypertension (P = 0.035), frequent premature supraventricular and ventricular contraction counts/24 h (P = 0.005 and P = 0.007, respectively), ventricular couplets/24 h (P = 0.002), and ventricular tachycardia (P = 0.004) were long-term predictors of AF. P-wave signal-averaged ECG revealed a limited long-term predictive value for AF. In chronic Chagas' disease, large left atrial diameter, pulmonary arterial hypertension, frequent supraventricular and ventricular premature beats, and ventricular tachycardia are long-term predictors of AF. The rate of left ventricular mass enlargement and systolic function deterioration impact AF incidence in this population.

Antivenom action on renal effects induced by Thalassophryne nattereri venom

Thalassophryne nattereri (niquim) is a venomous fish responsible for numerous accidents involving fishermen in northern and northeastern Brazil. The aim of the present investigation was to evaluate the action of antivenom on renal effects caused by Thalassophryne nattereri venom. Isolated kidneys of Wistar rats were perfused with a previously dialyzed Krebs-Henseleit solution containing 6 g% bovine serum albumin. The antivenom action was studied through perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF) and glomerular filtration rate (GFR). The niquim venom (1 miug/mL), the antivenom alone (1 miug/mL) or the venom incubated with antivenom were added to the system 30 minutes after the beginning of each perfusion. Previous works have shown venom induced-alterations of renal function parameters. In the isolated rat Kidney, T. nattereri venom (1 miug/mL) increased the perfusion pressure and renal vascular resistance at 60, 90 and 120 minutes. UF and GFR also increased at 60, 90 and 120 minutes when compared with the control group; however, no effects were observed on the percent of sodium (% TNa more control equal 81.1 more or less 0.86; % TNa more 60 equal 78.04 more or less 1.18; % TNa more 90 equal -5.16 more or less 3.34; %TNa more 120 equal 79.49 more or less 0.87) and potassium (%TKcontrol equal 72.29 more or less 1.12; %TK more 60 equal 75.41 more or less 0.65; % TK more 90 equal 71.23 more or less 2.55; % TK more 120 equal 76.62 more or less 1.04) tubular transporto. The administration of the antivenom (1 miug/mL) incubated with venom (1 miug/mL) reduced the changes in PP, RVR, UF and GFR provoked by Thalassophryne nattereri venom. The group perfused with venom alone showed a moderate deposit of a proteinaceous material in the tubules and urinary space.(...)

The inverted trophic cascade in tropical plankton communities: impacts of exotic fish in the Middle Rio Doce lake district, Minas Gerais, Brazil / A cascata trófica invertida em comunidades planctônicas tropicais: impactos da introdução de peixes exóticos no distrito de lagos do médio rio Doce, MG

The present study deals with the ecological impacts of the introduction of two alien species of piscivorous fish in several lakes of the Middle Rio Doce lake district in Minas Gerais, Brazil. It was demonstrated that these effects were not restricted only to the fish community. The introduction of the predatory red piranha Pygocentrus nattereri and the tucunaré Cichla cf. ocellaris caused not only a sharp decrease in the number of native fish species, but also major shifts in other trophic levels. Just after the fish were introduced, most lakes began to show conspicuous changes in phytoplankton species composition, in which Cyanophyceae gradually came to dominate. The zooplankton community lost several species, and in some cases, such as Lake Carioca, all the cladoceran species disappeared. On the other hand, invertebrate predators, represented by the dipteran Chaoboridae, boomed in the lake, with higher densities of exotic species, probably as a result of the "ecological release" by reduction of the original fish fauna. There was a general trend of species loss in different trophic levels. All these changes are apparently associated with decreases in water quality. The present situation in these lakes demands new approaches to the management and conservation of these ecosystems.

O presente estudo trata dos impactos ecológicos da introdução de duas espécies invasoras de peixes piscívoros em diversos lagos da região lacustre do médio rio Doce em Minas Gerais, Brasil. Demonstrou-se que estes efeitos não se restringiram às comunidade de peixes. A introdução dos predadores Pygocentrus nattereri (piranha-vermelha) e Cichla cf. ocelaris (tucunaré) não só causou uma forte redução no número de espécies de peixes nativos, como também mudanças nos níveis tróficos inferiores. Pouco depois das introduções, a maioria dos lagos começou a mostrar alterações na comunidade fitoplanctônica, tais como o aparecimento da dominância de Cyanophyceae. A comunidade zooplanctônica perdeu diversas espécies e, em alguns casos, houve o desaparecimento de todas as espécies de cladóceros limnéticos, como é o caso da lagoa Carioca. Por outro lado, predadores invertebrados, representados pelos dípteros da família Chaoboridae, floresceram nos lagos com maiores densidades de espécies exóticas de peixes, provavelmente como resultado da "liberação ecológica" causada pela redução da ictiofauna original. Além de uma tendência geral de perda de espécies em diferentes níveis tróficos, outras mudanças estão aparentemente associadas com a redução da qualidade de água. Dessa forma, esses ecossistemas estão necessitando urgentemente de novas abordagens nas estratégias de manejo e conservação.