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1.
Neotrop Entomol ; 49(6): 821-831, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32946024

RESUMO

In the present study, we analyzed a unique phytophysiognomy in the Amazon region, which is formed by savanna-like vegetation on iron-rich soil (known locally as canga) located within an iron-ore mining region. We used the habitat template theory to test the hypothesis that changes in the physical-chemical properties of streams and the physical structure of their habitats at in-stream and micro-basin (landscape) levels affect the taxonomic and trophic composition of immature aquatic insects. For this, we used a local environmental matrix composed of nine physical-chemical and structural habitat variables, together with the Habitat Integrity Index. We also calculated landscape metrics based on the area of the micro-basin, such as relief, slope, mean current flow, and vegetation cover. We divided the aquatic insects into five functional feeding groups based on their diet and food sources. Our results indicate that changes in the trophic level of the insects of the orders Ephemeroptera, Plecoptera, and Trichoptera are more easily observed than the taxonomic structure of communities. The loss of environmental integrity and vegetation cover were responsible for 84% of the variation observed in the composition of functional feeding groups (FFGs). Our study shows that aquatic insect communities in the canga and in the Amazon regions dominated by forest require specific in-stream and landscape conditions. These findings reinforce the need for the preservation of areas of canga vegetation, which not only have a unique levels of biological diversity, but are also targeted for the exploitation of their economically valuable natural resources.


Assuntos
Biodiversidade , Insetos/classificação , Rios , Animais , Organismos Aquáticos/classificação , Brasil , Florestas
2.
Neotrop Entomol ; 49(2): 191-202, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31989407

RESUMO

Aquatic systems have been degraded by environmental changes aimed at increasing the productivity of farmland and ranches. These changes affect aquatic assemblages at both local and regional scales. The hypothesis of this study is that in-stream environmental conditions are more important determinants of species richness and composition of Gerromorpha assemblage, given that they are affected directly by changes that occur within the stream, rather than by landscape conditions. To test our hypothesis, we collected at 20 sites of agricultural and forested regions in the Brazilian Cerrado. We relate predictors of the landscape and sites, of the streams with the assemblages of Heteroptera. While landscape metrics play an important role in the formation of stream conditions, local and physico-chemical variables had a significant influence on the structure of the Gerromorpha assemblages in the study area. This indicates that these organisms are more dependent on the processes that occur within the stream than those that occur outside the area of the gallery forest, considering the spatial scale of this study.


Assuntos
Heterópteros/crescimento & desenvolvimento , Rios , Agricultura , Animais , Brasil , Florestas , Pradaria , Dinâmica Populacional
3.
Neotrop Entomol ; 48(2): 186-196, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30259420

RESUMO

Determining thresholds of species loss in response to gradients of human impact is becoming an increasingly important component of stream conservation and management. We analyzed the thresholds of change in populations and communities of the infraorder Nepomorpha along a gradient of environmental integrity in streams of the Brazilian savannah, based on samples from 20 sites. We used the Threshold Indicator Taxa Analysis (TITAN) to identify the location and magnitude of changes associated with the environmental quality and the frequency and abundance of the different taxa. We also used TITAN to calculate the positive and negative thresholds of the community and species along the habitat integrity gradient. Nepomorphan species were generally associated with sites of higher environmental quality, which presented larger populations and greater species richness. Only a few nepomorphan species groups were associated with impacted streams. Thresholds were evident in some aquatic nepomorphan populations, but not for the community as a whole. This indicates that species have idiosyncratic responses to the environmental gradient, but in general nepomorphans appear to be a good indicator of healthy environments or less impacted streams in the Brazilian savannah.


Assuntos
Conservação dos Recursos Naturais , Monitoramento Ambiental , Heterópteros/classificação , Rios , Animais , Brasil , Ecossistema , Dinâmica Populacional
4.
Neotrop Entomol ; 46(1): 29-35, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27553721

RESUMO

Patterns of species' abundance and occurrence over time and space allow division of species into (i) common species, which are abundant, but have a low diversity, and (ii) rare species, which are far more diverse and less abundant. Understanding the relationships among these two species groups and how they are affected by environmental conditions is a major challenge for ecologists, especially considering the distinction between local environmental factors and regional factors and variations in abundance over the course of the year. In this study, we focused on the long-term relationship between the abundance of rare and common ephemeropterans and abiotic factors on local and regional scales. Our hypotheses are that common species will be affected primarily by regional environmental variables (i), whereas rare species will be influenced more by temporal variation (ii). Together, both local and regional abiotic variables, plus temporal variation, best explained the abundance of the common species, whereas temporal variation was the best predictor of rare species. Considering the theoretical aspects and the empirical evidence, we discuss the results based on the plasticity of the common species and the life cycle of the rare ones. We believe that our findings reinforce the need for the deconstruction of communities for a deeper understanding of their relationships with abiotic variables and, in particular, the specific aspects of these relationships in the context of the different guilds of the community.


Assuntos
Biodiversidade , Ephemeroptera , Animais , Brasil , Densidade Demográfica
5.
Stud Health Technol Inform ; 216: 1104, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26262403

RESUMO

This article describes the process of building an ontology to assist medical students and professionals specialized in Oncology. The ontology allows the user to obtain knowledge more quickly and thus assist professionals in their decision-making.


Assuntos
Ontologias Biológicas , Neoplasias da Mama/classificação , Mineração de Dados/métodos , Internet/organização & administração , Oncologia/organização & administração , Processamento de Linguagem Natural , Feminino , Humanos
6.
Neotrop Entomol ; 43(5): 421-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27193952

RESUMO

We demonstrate that the distribution of the functional feeding groups of aquatic insects is related to hierarchical patch dynamics. Patches are sites with unique environmental and functional characteristics that are discontinuously distributed in time and space within a lotic system. This distribution predicts that the occurrence of species will be based predominantly on their environmental requirements. We sampled three streams within the same drainage basin in the Brazilian Cerrado savanna, focusing on waterfalls and associated habitats (upstream, downstream), representing different functional zones. We collected 2,636 specimens representing six functional feeding groups (FFGs): brushers, collector-gatherers, collector-filterers, shredders, predators, and scrapers. The frequency of occurrence of these groups varied significantly among environments. This variation appeared to be related to the distinct characteristics of the different habitat patches, which led us to infer that the hierarchical patch dynamics model can best explain the distribution of functional feeding groups in minor lotic environments, such as waterfalls.


Assuntos
Distribuição Animal , Organismos Aquáticos , Biodiversidade , Insetos , Animais , Brasil , Ecossistema , Pradaria
7.
J Ethnopharmacol ; 93(2-3): 385-9, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15234782

RESUMO

An infusion of Campomanesia xanthocarpa Berg. (Myrtaceae) leaves (Guabiroba) and the herb Cuphea carthagenensis (Jacq.) J.F. Macbr. (Lythraceae) (Sete-sangrias) is traditionally used in the South of Brazil to treat high levels of cholesterol and triglycerides. The effects of the aqueous extracts of these herbs were investigated in rats fed on a high calorie diet. Chronic treatment with the Guabiroba aqueous extract induced a significant reduction in weight gain in the rats, compared to the control group. Also, biochemical analysis showed that this treatment reduced the glycemia, while no effects on lipidic levels were observed. The biochemical analysis of the animals treated with Sete-sangrias aqueous extract showed no effect on glucose and triglyceride levels, while chronic treatment with the Sete-sangrias aqueous extract induced a significant reduction in plasma cholesterol in rats.


Assuntos
Cuphea , Hipolipemiantes/farmacologia , Myrtaceae , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Glicemia/efeitos dos fármacos , Colesterol/sangue , Hipolipemiantes/administração & dosagem , Hipolipemiantes/uso terapêutico , Masculino , Obesidade/prevenção & controle , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Folhas de Planta , Ratos , Ratos Wistar , Triglicerídeos/sangue , Redução de Peso
8.
Rev Soc Bras Med Trop ; 34(4): 349-55, 2001.
Artigo em Português | MEDLINE | ID: mdl-11562728

RESUMO

HBV and HDV infections are a major health problem in the Amazon. This study evaluates the prevalence of these viruses within Indians groups, measuring the frequency of serological markers. The prevalence of past infection was 54.5% and HBsAg was found in 9.7%. An important variation of those markers was detected between villages, inclusively within the same ethnic group. None showed evidence of an acute infection. All HBeAg reactive were Apurinã, living in the same village and three of them from the same family. The prevalence of anti-HDT was 13.4% in HBsAg positive individuals. The authors observed high prevalence of HBV and HDV infection with the following pattern: low degree of infectivity, marked transmission in early ages, intra-familial dissemination, and lack of importance of vertical transmission. However, the results suggest that these viruses were not yet introduced effectively in some of the studied groups.


Assuntos
Hepatite B/epidemiologia , Hepatite D/epidemiologia , Indígenas Sul-Americanos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade
9.
Arq Bras Cardiol ; 77(2): 120-31, 2001 Aug.
Artigo em Inglês, Português | MEDLINE | ID: mdl-11514823

RESUMO

OBJECTIVE: To evaluate the immediate results of percutaneous mechanical mitral commissurotomy. METHODS: Thirty patients underwent percutaneous mechanical mitral commissurotomy performed with a Cribier's metallic valvulotome from 8/11/99 to 2/4/00. Mean age was 30.7 years, and 73.3% were women. With regards to functional class, 63.3% were class III, and 36.7% were class IV. The echocardiographic score had a mean value of 7.5+/- 1.8. RESULTS: The mitral valve area increased from 0.97+/-0.15cm2 to 2.16+/-0.50cm2 (p>0.0001). The mean diastolic gradient decreased from 17.9+/-5.0mmHg to 3.2+/-1.4mmHg. The mean left atrial pressure decreased from 23.6+/-5.4mmHg to 8.6+/-3.1mmHg, (p>0.0001). Systolic pressure in the pulmonary artery decreased from 52.7+/-18.3mmHg to 32.2+/-7.4mmHg. Twenty-nine cases were successful. One patient developed severe mitral regurgitation. Interatrial septal defect was observed and one patient. One patient had cardiac tamponade due to left ventricular perforation. No deaths occurred. CONCLUSION: This method has proven to be safe and efficient in the treatment of rheumatic mitral stenosis. The potential advantage is that it can be used multiple times after sterilization, which decreases procedural costs significantly.


Assuntos
Oclusão com Balão , Cateterismo/métodos , Estenose da Valva Mitral/terapia , Adulto , Cateterismo/instrumentação , Angiografia Coronária , Feminino , Humanos , Masculino , Estenose da Valva Mitral/diagnóstico por imagem , Resultado do Tratamento , Ultrassonografia
10.
Int J Med Inform ; 63(1-2): 19-30, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11518662

RESUMO

This paper proposes a hybrid expert system (HES) to minimise some complexity problems pervasive to the artificial intelligence such as: the knowledge elicitation process, known as the bottleneck of expert systems; the model choice for knowledge representation to code human reasoning; the number of neurons in the hidden layer and the topology used in the connectionist approach; the difficulty to obtain the explanation on how the network arrived to a conclusion. Two algorithms applied to developing of HES are also suggested. One of them is used to train the fuzzy neural network and the other to obtain explanations on how the fuzzy neural network attained a conclusion. To overcome these difficulties the cognitive computing was integrated to the developed system. A case study is presented (e.g. epileptic crisis) with the problem definition and simulations. Results are also discussed.


Assuntos
Inteligência Artificial , Técnicas de Apoio para a Decisão , Algoritmos , Lógica Fuzzy , Humanos
11.
Rev. Soc. Bras. Med. Trop ; 34(4): 349-355, jul.-ago. 2001. mapas, tab, graf
Artigo em Português | LILACS | ID: lil-461933

RESUMO

HBV and HDV infections are a major health problem in the Amazon. This study evaluates the prevalence of these viruses within Indians groups, measuring the frequency of serological markers. The prevalence of past infection was 54.5% and HBsAg was found in 9.7%. An important variation of those markers was detected between villages, inclusively within the same ethnic group. None showed evidence of an acute infection. All HBeAg reactive were Apurinã, living in the same village and three of them from the same family. The prevalence of anti-HDT was 13.4% in HBsAg positive individuals. The authors observed high prevalence of HBV and HDV infection with the following pattern: low degree of infectivity, marked transmission in early ages, intra-familial dissemination, and lack of importance of vertical transmission. However, the results suggest that these viruses were not yet introduced effectively in some of the studied groups.


A infecção pelo VHB e VHD são importantes problemas de saúde na Amazônia. Este estudo avalia a prevalência da infecção por esses agentes em sete grupos indígenas do Estado do Amazonas. A taxa de infecção passada pelo VHB encontrada foi de 54,5% e a de portadores do AgHBs de 9,7%. Observa-se variação importante destes marcadores entre as aldeias, inclusive da mesma etnia. Não evidenciamos marcador de infecção aguda, os quatro AgHBe reativos eram todos Apurinã, da mesma aldeia, e três da mesma família. O VHD foi encontrado em 13,4% dos AgHBs reativos. O padrão de infecção pelo VHB e VHD encontrado possui as seguintes características: endemicidade elevada, baixo potencial de infectividade, transmissão marcada em idade precoce, provável transmissão familiar, e pouca importância da transmissão vertical. Entretanto, também sugere que esses vírus não tenham sido ainda introduzidos efetivamente em algumas das etnias estudadas


Assuntos
Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adolescente , Adulto , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Hepatite B/epidemiologia , Hepatite D/epidemiologia , Indígenas Sul-Americanos , Brasil/epidemiologia
12.
Artif Intell Med ; 21(1-3): 227-33, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11154890

RESUMO

This work presents a hybrid expert system (HES) intended to minimise some complex problems pervasive to knowledge engineering such as: the knowledge elicitation process, known as the bottleneck of expert systems; the choice of a model for knowledge representation to codify human reasoning; the number of neurons in the hidden layer and the topology used in the connectionist approach; the difficulty to extract an explanation from the network. Two algorithms applied to developing of HES are also suggested. One of them is used to train the fuzzy neural network and the other to obtain explanations on how the fuzzy neural network attained a conclusion. A case study is presented (e.g. epileptic crisis) with the inclusion of problem definition and simulations. The results are also discussed.


Assuntos
Algoritmos , Inteligência Artificial , Epilepsia/diagnóstico , Doença Aguda , Diagnóstico Diferencial , Epilepsia/patologia , Humanos , Índice de Gravidade de Doença
13.
Ann Thorac Surg ; 66(1): 56-9, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9692438

RESUMO

BACKGROUND: Tumor necrosis factor-alpha has been implicated in complications seen after cardiac operations with cardiopulmonary bypass. The release of tumor necrosis factor-alpha and its possible effects were studied in patients undergoing coronary artery bypass grafting with and without cardiopulmonary bypass. METHODS: Twenty patients were studied, 10 with (group 1) and 10 without cardiopulmonary bypass (group 2). Serial blood samples were obtained before, during, and up to 48 hours after operation. Circulating tumor necrosis factor-alpha levels, leukocyte counts, and erythrocyte sedimentation rates were measured. Hemodynamic variables (blood pressure and heart rate), temperature, orotracheal intubation time, postoperative bleeding, and inotropic drug requirements were compared. RESULTS: Serum levels of tumor necrosis factor-alpha were detected in 6 patients (60%) in group 1 and none in group 2. The patients in group 1 had more hypotension than those in group 2 (7.4 +/- 1.0 mm Hg versus 8.5 +/- 0.7 mm Hg), required more inotropic drugs (8 patients versus 1 patient), and had a higher heart rate (114 +/- 8 beats per minute versus 98 +/- 10 beats per minute), a higher temperature (37.1 degrees +/- 0.5 degrees C versus 36.6 degrees +/- 0.3 degrees C), increased postoperative bleeding (820 +/- 120 mL versus 360 +/- 84 mL), a longer orotracheal intubation time (13.6 +/- 2.2 hours versus 9.3 +/- 1.4 hours), and a more pronounced leukocytosis. CONCLUSIONS: Cardiopulmonary bypass induces the whole-body inflammatory response through the release of tumor necrosis factor alpha, resulting in adverse systemic effects.


Assuntos
Ponte Cardiopulmonar/efeitos adversos , Ponte de Artéria Coronária/efeitos adversos , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Fator de Necrose Tumoral alfa/fisiologia , Pressão Sanguínea/fisiologia , Sedimentação Sanguínea , Temperatura Corporal/fisiologia , Feminino , Seguimentos , Frequência Cardíaca/fisiologia , Humanos , Hipotensão/etiologia , Intubação Intratraqueal , Contagem de Leucócitos , Leucocitose/etiologia , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/efeitos dos fármacos , Hemorragia Pós-Operatória/etiologia , Síndrome de Resposta Inflamatória Sistêmica/sangue , Fatores de Tempo , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/metabolismo
14.
Ann Thorac Surg ; 66(1): 256-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9692480

RESUMO

This is a case of a patient with two saccular aneurysms in the descending aorta. Two self-expanding stents were inserted through an opening in the aortic arch, guided by the use of an Olympus endoscope, under profound hypothermia and total circulatory arrest. The bloodless field made possible the identification of the main thoracic branches, facilitating the positioning and deployment of both stents. Immediate postoperative recovery was excellent.


Assuntos
Angioscopia , Aneurisma da Aorta Torácica/terapia , Stents , Idoso , Angioscópios , Aorta Torácica/patologia , Aneurisma da Aorta Torácica/patologia , Desenho de Equipamento , Parada Cardíaca Induzida , Humanos , Hipotermia Induzida , Masculino , Artéria Mesentérica Superior/patologia , Polietilenotereftalatos , Artéria Renal/patologia , Aço , Técnicas de Sutura
15.
Ann Thorac Surg ; 65(4): 1135-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9564944

RESUMO

We describe a case of a patient who had a ruptured aorta repaired by femorofemoral bypass with an interposition graft and subsequently had a graft infection. The patient was taken to operation and the old graft was removed. It was replaced by a spiral great saphenous vein graft. The patient has been followed up for 36 months with computed tomographic scanning, which has shown that the vein graft has not dilated.


Assuntos
Aorta Torácica/cirurgia , Prótese Vascular/efeitos adversos , Infecções Relacionadas à Prótese/cirurgia , Veia Safena/transplante , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/cirurgia , Adulto , Aneurisma da Aorta Torácica/cirurgia , Ruptura Aórtica/cirurgia , Implante de Prótese Vascular/efeitos adversos , Ponte Cardiopulmonar/métodos , Artéria Femoral , Veia Femoral , Seguimentos , Humanos , Imipenem/uso terapêutico , Masculino , Polietilenotereftalatos , Desenho de Prótese , Infecções Relacionadas à Prótese/tratamento farmacológico , Reoperação , Veia Safena/diagnóstico por imagem , Tienamicinas/uso terapêutico , Tomografia Computadorizada por Raios X
17.
s.c; s.n; jan. 1989. [9] p.
Não convencional em Português | Sec. Est. Saúde SP, SESSP-CTDPROD, Sec. Est. Saúde SP, SESSP-ACVSES | ID: biblio-1077040
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