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1.
J Mol Model ; 30(7): 231, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935147

RESUMO

CONTEXT: The conversion of carbon dioxide (CO2) to formic acid (FA) through hydrogenation using 1-ethyl-2,3- dimethyl imidazolium nitrite (EDIN) ionic liquid was studied to understand the catalytic roles within EDIN. CO2 hydrogenation in various solvents has been explored, but achieving high efficiency and selectivity remains challenging due to the thermodynamic stability and kinetic inertness of CO2. This study explored two mechanistic pathways through theoretical calculations, revealing that the nitrite (NO2-) group is the most active site. The oxygen site on nitrite favorably activates H2, while the nitrogen site shows a minor activation barrier of 108.90 kJ/mol. The Gibbs energy variation indicates stable FA formation via EDIN, suggesting effective hydrogen (H2) activation and subsequent CO2 conversion. These insights are crucial for developing improved catalytic sites and processes in ionic liquid catalysts for CO2 hydrogenation. METHODS: Quantum chemical calculations were conducted using the ORCA software package at the Restricted Hartree-Fock (RHF) and density functional theory (DFT) levels. The RHF method, known for its predictive abilities in simpler systems, provided a baseline description of electronic structures. In contrast, DFT was employed for its effectiveness in complex interactions involving significant electron correlation. A valence triple-zeta polarization (def2-TZVPP) basis set was employed for both RHF and DFT, ensuring accurate and correlated calculations. The B3LYP functional was utilized for its rapid convergence and cost-efficiency in larger molecules. Dispersion corrected functionals (DFT-D) addressed significant dispersion forces in ionic liquids, incorporating Grimme's D2, D3, and D4 corrections. Geometry optimizations, kinetics, and thermodynamic calculations were performed in the gas phase. The Nudged Elastic Band Transition State (NEB-TS) approach, combining Climbing Image-NEB (CINEB) and Eigenvector-Following (EF) methods, was used to find the minimum energy path (MEP) between reactants and products. Thermochemical analyses based on vibrational frequency calculations evaluated properties such as Enthalpy, Entropy, and Gibbs energy using ideal gas statistical mechanics.

2.
Fish Physiol Biochem ; 43(4): 1033-1041, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28197867

RESUMO

Most water bodies in Brazil, and in the world, are contaminated by some types of pollutants, ranging from sewage to metal/chemicals, carcinogenic products, and biodegradable detergents. Despite the extensive knowledge on their effects on fish biology and especially on gill morphology, research that concerns their impacts on gill rakers and implications in parameters such as food consumption cannot be found in the literature. Gill rakers are vital because, together with gills, they are responsible for the defense and protection of the organism and for selecting appropriate food for survival. When detergents, which can act as toxic chemical agents, get in contact with the body of the fish, they can cause severe effects that must be understood. Therefore, our study investigated ultramorphological changes in gill rakers of Astyanax altiparanae (Lambeth) caused by the exposure to biodegradable detergents. Fish were exposed to a 1 mg/L dilution of a mixture of detergents and pure water from an artesian well for 5 months. Results revealed that the first month of exposure to detergent caused dilation of chemical receptors in taste buds and the rise of a large number of orifices for mucus release among pavement cells in gill rakers, although only a small amount of mucus was found in fish exposed both to pure water and the detergent dilution. After 5 months, there was an increase in the dilation of these chemoreceptors, excess mucus on gill rakers of detergent groups, and the emergence of microbridges between microridges in pavement cells.


Assuntos
Characidae/anatomia & histologia , Detergentes/toxicidade , Brânquias/efeitos dos fármacos , Brânquias/ultraestrutura , Poluentes Químicos da Água/toxicidade , Animais , Feminino , Masculino
3.
Ecotoxicol Environ Saf ; 129: 43-50, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26990938

RESUMO

Increasing pollution levels have turned our attention to assessing lethal and sublethal effects of toxic agents using the most informative techniques possible. We must seek non-invasive or non-lethal sampling methods that represent an attractive alternative to traditional techniques of environmental assessment in fish. Detergents are amongst the most common contaminants of water bodies, and LAS (Linear Alkylbenzene Sulfonate) is one of the most used anionic surfactant on the market. Our study analyzed morphological alterations (histological and histochemical) of the scale epithelium of Prochilodus lineatus under exposure to two concentrations of LAS, 3.6mg/L and 0.36mg/L, for a period of 30 days and evaluated at 14, 21 and 30 days. In order to establish morphological analysis of the scale epithelium as a new non-lethal environmental assessment tool that is reliable and comparable to classic methods, the relative sensibility of this technique was compared to a commonly used method of environmental assessment in fish, the estimation of the effects of pollutants upon branchial morphology. Two experiments were carried out, testing animals in tanks, and in individual aquariums. Results of analyses on gill tissue show that exposure to 3.6mg/L of surfactant caused severe damage, including hyperplasia, hypertrophy and fusion at 14 days, with aneurisms at 21 and 30 days; while exposure to 0.36mg/L had lighter effects on the organ, mainly lower incidence of fusion and hyperplasia. Aditionally, scale morphology was altered severely in response to 3.6mg/L of LAS, consistently showing increased mucous and club cell production. Epithelial thickness was the most variable parameter measured. Scale epithelium sensibility has the potential to be a reliable environmental marker for fish species since it has the advantage of being less invasive when compared to traditional methods. However, more studies are required to increase the robustness of the technique before it can be generally applied.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Pele/efeitos dos fármacos , Tensoativos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Caraciformes , Epitélio/efeitos dos fármacos , Epitélio/patologia , Pele/patologia
4.
Artigo em Português | LILACS | ID: lil-718808

RESUMO

As propriedades de barreira à umidade de embalagens plásticas para produtos oftálmicos de capacidade nominal de 20 mL e terminação 15 mm nos formatos cilíndrico e oval, de diferentes composições (100% Polietileno de Baixa Densidade (PEBD), 100% Polipropileno (PP) e blendas com percentuais 10% e 40% de Polietileno de Alta Densidade (PEAD) em PEBD), foram estudadas neste trabalho. Foi verificada também a influência do batoque gotejador (de maior ou menor orifício de dosagem) e a influência do fechamento na taxa de transmissão de vapor d'água. O trabalho foi conduzido sob duas condições de estocagem a 25 ºC/40% UR e a 40 ºC/75% UR. Verificou-se que o diâmetro do orifício gotejador não interferiu significativamente na perda de peso da embalagem avaliada a 25 ºC/40% UR. Sob a condição de estocagem a 40 ºC/75% UR verificou-se um aumento da taxa de transmissão de vapor d'água das embalagens comparativamente as mesmas embalagens avaliadas a 25 ºC/40% UR. O sistema de fechamento não favoreceu um acréscimo significativo da taxa de transmissão de vapor d'água, o que indica que a permeação ocorreu principalmente através do corpo da embalagem plástica. A propriedade de barreira foi influenciada pela composição da embalagem plástica chegando a uma redução média de 47% na taxa de transmissão de vapor d'água para a embalagem de PEBD com 40% PEAD em relação à embalagem com100% PEBD de formato cilíndrico. Verificou-se ainda que o formato oval, por apresentar uma maior área superficial exposta comparativamente à embalagem de formato cilíndrico, com regiões de menor espessura de parede, pode favorecer um ligeiro aumento da taxa de transmissão de vapor d'água da embalagem...


The moisture barrier properties of plastic ophthalmic product bottles of nominal capacity 20 mL and finish diameter 15 mm, in cylindrical and oval shapes, with various compositions (100% Low Density Polyethylene(LDPE), 100% polypropylene (PP) and blends with10% and 40% High Density Polyethylene (HDPE) in LDPE), were assessed in this study. The effects of the drop hole size (higher or lower dosage diameter) and the screw cap on the Water Vapor Transmission Rate (WVTR) were also assessed. This study was conducted under two conditions of storage, at 25 °C/40% RH and 40 °C/75% RH. It was observed that the drop hole diameter did not influence significantly the weight loss of the container at 25 °C/40% RH, whereas at 40°C/75% RH, the WVTR of the container was higher than that of the same package at 25 °C/40% RH.The screw cap did not significantly affect the WVTR, indicating that the permeation occurred primarily through the plastic body. The barrier property was influenced by the composition of the plastic container; thus, compared to LDPE, there was a mean reduction of 47% in the WVTR of LDPE blended with 40% HDPE, when both bottles were cylindrical. It was found that the oval shape, because of the larger exposed surface area relative to the cylindrical shape, as well as the presence of regions of thinner wall, can favor a slight increase in the WVTR of the bottle...


Assuntos
Embalagem de Medicamentos , Umidade , Soluções Oftálmicas/análise , Vapor/efeitos adversos
5.
Braz J Biol ; 73(3): 637-44, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24212706

RESUMO

The fish body is entirely covered by a thin, smooth and glandular epidermis, closely attached to the scales inserted on the dermis. The descriptive work on this tissue dates to twenty or thirty years ago, bears very little photographic record and does not focus on the scale epithelium, despite the fact that it is in direct contact with the environment. Thereupon, the present study characterizes the scale epithelium of Prochilodus lineatus, a robust species of fish. The observations show that the scale is completely covered by epithelium thicker on the proximal end of the scale, multilayered on the dorsal surface and undifferentiated on the ventral surface, and covered by mucous producing cells, mostly acid mucous. The scale is formed by plywood-like collagen matrix of collagen type III and supported by a network of elastic fibers on the ventral face. Differentiated cellular types are present, such as club cells, considered to be responsible for the release of alarm substances, which suggests possible use in environmental assessment as a non-invasive technique.


Assuntos
Caraciformes/anatomia & histologia , Caraciformes/classificação , Epitélio/anatomia & histologia , Animais , Brasil , Monitoramento Ambiental , Histocitoquímica
6.
Arch Gerontol Geriatr ; 56(2): 343-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22939428

RESUMO

Frailty is a clinical condition associated with pathological aging and biological vulnerability. In the spectrum of events related to frailty, aging of the cardiocirculatory system and abnormalities in arterial blood pressure (BP) partly explain the changes in tissue perfusion and, potentially, the decrease in physiological reserves. This study investigated the relationship between BP levels, systemic arterial hypertension (SAH) and the frailty phenotype by analyzing frailty criteria in a cross-sectional model into the FIBRA network, a populational sample of community-dwelling elders in Southeastern Brazil. Study participants with ≥65 years were selected by probabilistic sampling of residents in the urban area of the municipality of Campinas (n=900). Considering frailty as a whole and the difference between genders, there was a greater proportion of frail or pre-frail individuals among women than men. Analysis of individual frailty criteria showed that weight loss and fatigue were more common among women (18.3% vs. 12.5%, p=0.034 and 22.5% vs. 11.9%, p<0.001, respectively). Comparison of individuals with or without SAH failed to reveal any differences related to frailty criteria. Nevertheless, averages of diastolic blood pressure (DBP) and mean arterial blood pressure values were lower among elderly individuals with reduced grip strength, physical activity and the frailty classification as a whole (OR 0.986, IC 0.975-0.997) (for every 1 mmHg reduction in MBP values, the likelihood of being frail increased 1.4%). Our findings corroborate the relationship between BP values and frailty in the elderly and contribute to an understanding of the pathophysiological mechanisms of the syndrome.


Assuntos
Pressão Sanguínea/fisiologia , Idoso Fragilizado , Avaliação Geriátrica/métodos , Hipertensão/fisiopatologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Fenótipo , Prevalência , Estudos Retrospectivos
7.
Artigo em Português | LILACS | ID: lil-593804

RESUMO

O objetivo deste estudo foi caracterizar e verificar a influência de microfissuras na manutenção da esterilidade e do desempenho mecânico de frascos de vidro tipo I, de 4 mL e 13 mL (terminação 13 mm) para produtos esterilizáveis e de 7 mL (terminação 20 mm) para produtos liofilizados, após acondicionamento em linha e simulação de transporte. Microfissuras superficiais em frascos de vidro tipo I podem ser formadas devido ao contato entre o vidro e o ferramental, associado a variações na intensidade da chama, durante o processo produtivo da embalagem. Verificou-se que a tensão residual da embalagem não é alterada pela presença das microfissuras e que os sistemas de fechamento apresentam adequada integridade e propriedades de barreira à umidade. Mesmo com microfissuras superficiais, a manutenção da esterilidade do produto simulante, acondicionado nos frascos esterilizados (4 mL e 13 mL), não apresentaram alteração após o envase em linha e simulação de transporte. No caso do frasco de 7 mL, as microfissuras podem ter contribuído para a ocorrência de alteração de 1% do total das embalagens após o processo de liofilização. Uma maior incidência de quebra por carga vertical, localizada na região do ombro/terminação, foi observada devido à presença das microfissuras. O desempenho mecânico e térmico dos frascos estudados, contudo, não foi alterado pela presença das microfissuras.


The objective of this study was to ascertain the influence of microcracks on the maintenance of sterility and echanical performance of type 1 (i.e. borosilicate) glass vials, of 4 mL and 13 mL (neck 13 mm) for sterile pharmaceutical products and 7 mL (neck 20 mm) for freeze-dried products, after in-line filling and transport simulation. Microcracks in type I glass vials can be formed by contact between the glass and metal tools, when variations in the flame temperature occur during manufacturing. It was found that the residual stress in the glass vials is not altered by the presence of microcracks and that the closure systems are secure and have adequate moisture barrier properties. Even with surface microcracking, the sterility of the simulated product in the vials (4 mL and 13 mL) was maintained after the in-line filling and transport simulation; for the 7 mL glass vial, microcracks may have contributed to the loss of sterility of 1% of the products after freeze-drying. A higher incidence of breakage in the region of the shoulder and neck of the glass vials under vertical load was observed in the presence of microcracks. The mechanical and thermal performance of the glass vials, however, was not impaired by the presence of microcracks.


Assuntos
Indústria Farmacêutica , Embalagem de Medicamentos , Tecnologia de Produtos
8.
Int J Infect Dis ; 14(10): e898-903, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20843719

RESUMO

BACKGROUND: An epidemic of acute gastroenteritis occurred in Rio Branco City, Acre State, in Brazil's Amazon region in 2005. An investigation was conducted to confirm the etiology and identify possible risk factors for death. METHODS: Rio Branco municipality surveillance data for the period May to October 2005 were reviewed. In a case-control study, children who died following acute gastroenteritis were compared to age-matched controls with acute gastroenteritis who survived. Rotavirus A (RV-A) was investigated in 799 stool samples and genotyped by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: The cumulative incidence of diarrhea in children aged <5 years was 21%. A fatal outcome was significantly associated with uncovered household water storage containers. RV-A was identified in 88% of samples and G9 was the prevalent genotype (71%). CONCLUSIONS: Oral rehydration solution and boiling or chlorinating drinking water likely limited mortality. This epidemic was caused by RV-A genotype G9. After the outbreak, a rotavirus vaccine was introduced into the official childhood immunization schedule in Brazil.


Assuntos
Surtos de Doenças , Gastroenterite/epidemiologia , Infecções por Rotavirus/epidemiologia , Rotavirus/isolamento & purificação , Doença Aguda , Brasil/epidemiologia , Estudos de Casos e Controles , Pré-Escolar , Gastroenterite/mortalidade , Gastroenterite/virologia , Genótipo , Humanos , Lactente , Fatores de Risco , Rotavirus/genética , Infecções por Rotavirus/mortalidade , Infecções por Rotavirus/virologia
9.
Rev. ciênc. farm. básica apl ; 29(2): 167-178, 2008. graf, tab
Artigo em Português | LILACS | ID: lil-514286

RESUMO

A estabilidade de produtos farmacêuticos fotossensíveis é afetada pela luz, que catalisa reações de degradação. O objetivo deste estudo foi avaliar a eficiência de diferentes resinas, coloração, espessura e presença de absorvedores de radiação ultravioleta (UV) comopromotores de barreira à luz em embalagens plásticas e de vidro para produtos farmacêuticos. A Farmacopéia Americana estabelece limites entre 10 e 25% de transmissão de luz entre 290 e 450 nm para embalagens de medicamentos. Nenhum dos frascos sem coloração mostrou-se adequado, sendo aqueles que apresentaram menor transmissão foram o de vidro e o de politereftalato de etileno (PET), até 350 nm, e o de polietileno de baixa densidade (PEBD) no restante do espectro. Aamostra de polipropileno (PP) apresentou a maior taxa de transmissão até 300 nm, ficando próxima das demais amostras a partir daí. No frasco de PET cristal com absorvedor de radiação UV, observou-se redução significativa nas transmitâncias até 350 nm, chegando à mesma percentagem que o PET sem absorvedor acima deste comprimento de onda. As amostras de PET âmbar, verde e branco apresentaram a melhor barreira à luz dentre os frascos de PET coloridos. As chapas de policloreto de vinila (PVC) apresentaram-se similares às de PET (tanto cristal quanto coloridas), sendo que as chapas de policloreto de vinila / policloreto de vinilideno (PVC/PVdC) e policloreto de vinila /policlorotrifluoretileno (PVC/Aclar) apresentaram transmissão similar à do PVC com absorvedor de UV. A embalagem de PP azul apresentou maior barreira que o PP natural, mas não é adequada segundo a Farmacopéia. A espessura se mostrou diretamente proporcional à barreira, tanto nas embalagens de PET quanto nas de vidro.


Assuntos
Embalagem de Medicamentos/normas , Luz/efeitos adversos , Preparações Farmacêuticas/efeitos da radiação
10.
Braz J Biol ; 66(2B): 731-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16906305

RESUMO

Many stingless bee species are specific to their areas of occurrence. Even when adapted to their local climate and flora conditions, they are subject to modifications in the environment, directly influencing flight activity. The aim of this work is to obtain information about the flight activity of the stingless bee Melipona asilvai Moure, thus contributing to the knowledge of this species. The flow of bees entering and leaving the colony was evaluated, and the type of transported material was identified. This information was correlated with climatic data collected at the time of observations, performed between June 2002 and March 2003. It can be proved that temperature was the factor with the greatest influence on the external activity of this species, showing a significant positive correlation with the entry of bees into the colony and pollen collection. Mud collecting showed a significant positive correlation with a humidity increase. Flight activity began at a temperature of 21.0 degrees C and humidity of 84.5%, peaking at 27.4 degrees C and 60.6% RH, respectively.


Assuntos
Abelhas/fisiologia , Voo Animal/fisiologia , Animais , Umidade , Estações do Ano , Temperatura , Fatores de Tempo
11.
Braz. j. biol ; 66(2b): 731-737, May 2006. graf
Artigo em Inglês | LILACS | ID: lil-433158

RESUMO

Muitas espécies de meliponíneos são específicas de suas regiões de ocorrência. Mesmo sendo adaptadas às condições locais de clima e flora, estão sujeitas às modificações do ambiente externo, influenciando diretamente a sua atividade de vôo. Este trabalho teve como objetivo obter informações sobre a atividade de vôo de Melipona asilvai Moure, contribuindo para o conhecimento desta espécie. Foi avaliado o fluxo de abelhas, entrando e saindo da colônia, e a identificação do tipo de material transportado. Estas informações foram correlacionadas com dados climáticos coletados no momento das observações, realizadas entre junho de 2002 e março de 2003. A temperatura foi o fator de maior influência sobre a atividade de vôo desta espécie, apresentando correlação positiva significativa com a entrada de abelhas na colônia e com a coleta de pólen. A coleta de barro apresentou correlação positiva significativa com o aumento da umidade. A atividade de vôo foi iniciada à temperatura de 21,0 °C e umidade de 84,5%, apresentando pico com 27,4 °C e 60,6%, respectivamente.


Assuntos
Animais , Abelhas/fisiologia , Voo Animal/fisiologia , Umidade , Estações do Ano , Temperatura , Fatores de Tempo
12.
Epidemiol Infect ; 132(5): 985-92, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15473163

RESUMO

Vibrio cholerae is an important human pathogen and the cause of cholera. Since genetic variation and antibiotic resistance of strains have implications for effective treatment of the disease, we examined the genetic diversity and antibiotic resistance profile in 92 clinical strains (serogroup O1) and 56 environmental strains (O1 antigen, 42 strains; non-O1 antigen, 14 strains) isolated in Brazil between 1991 and 1999. Clinical and environmental O1 strains showed greater drug resistance compared to environmental non-O1 strains. Nearly all clinical O1 strains were resistant to one or more antibiotics while half of the environmental O1 and non-O1 strains were resistant to one or more antibiotics. No plasmids or class 1 integrons were detected in the strains by PCR analysis. Multilocus enzyme electrophoresis analysis (MLEE) suggests most of the O1 strains belong to a single (South American) clone that is related but different to seventh-pandemic strains isolated from other parts of the world. Our results show that there is a close genetic relationship between clinical and environmental O1 strains and that many serogroups and the environment can be a reservoir for antibiotic resistance.


Assuntos
Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana/genética , Vibrio cholerae/efeitos dos fármacos , Vibrio cholerae/genética , Anti-Infecciosos/uso terapêutico , Brasil/epidemiologia , Cólera/tratamento farmacológico , Cólera/epidemiologia , Cólera/microbiologia , Primers do DNA , DNA Bacteriano/análise , Reservatórios de Doenças , Eletroforese , Humanos , Reação em Cadeia da Polimerase , Vibrio cholerae/enzimologia
13.
Rev. bras. farmacogn ; 14(1): 49-56, 2004. ilus
Artigo em Português | LILACS | ID: lil-570842

RESUMO

Congonha, congonha-de-bugre e bugre são nomes populares atribuídos a várias espécies medicinais, incluindo Rudgea viburnoides (Cham.) Benth. (Rubiaceae), cujas folhas são utilizadas na medicina popular como diuréticas, hipotensoras, antireumáticas e depurativas do sangue. Esta espécie vem sendo comercializada como porangaba e utilizada em regimes de emagrecimento, substituindo Cordia ecalyculata Vell. (Boraginaceae). Neste estudo, foram determinadas as características botânicas, fisico-químicas e químicas para R. viburnoides com o objetivo de auxiliar sua identificação taxonômica e o controle de qualidade de produtos preparados com esta planta. Uma amostra referência foi coletada e submetida à caracterização macroscópica, microscópica e organoléptica, determinação de cinzas totais e umidade, prospecção fitoquímica e determinação dos perfis cromatográficos em CCD. Amostras de R. viburnoides podem ser reconhecidas pela epiderme pilosa com marcantes estrias cuticulares, estômatos paracíticos, presença de idioblastos com ráfides no mesofilo e pela configuração em arco dos tecidos vasculares da nervura de primeira ordem, caracteres ausentes em C. ecalyculata. A presença de cistólitos e canais mucilaginosos na medula diferem prontamente C. ecalyculata de R. viburnoides. A análise por CCD evidenciou a presença de flavonóides e saponinas. Amostras adquiridas no comércio e submetidas aos mesmos ensaios permitiram validar os métodos propostos e confirmaram a ampla comercialização de R. viburnoides em Minas Gerais.


Congonha, congonha-de-bugre and bugre are popular names for several medicinal plant species, including Rudgea viburnoides (Cham.) Benth. (Rubiaceae), whose leaves are widely used in popular medicine as diuretic, hypotensive, antirheumatic, and blood depurative. This species has been commercialized as porangaba, and used for diet purposes in substitution of Cordia ecalyculata Vell. (Boraginaceae). This study determines botanical, physico-chemical and chemical characteristics of R. viburnoides with the objective of providing tools for its taxonomical identification and the quality control of derived products. A reference sample was collected and submitted to macroscopical, microscopical and organoleptical characterization, total ash and water content, phytochemical screening, and TLC profile determination. Samples of Rudgea viburnoides can be easily distinguished from those of Cordia ecalyculata by the pilose epidermis with paracytic stomata, outstanding cuticularized striation, the presence of cristalliferous idioblasts, and by the arc pattern of the midvein vascular tissues. Furthermore, C. ecalyculata presents cystoliths and medullary mucilaginous channels differing from R. viburnoides. TLC analysis demostrated the presence of flavonoids and saponins. Commercially acquired samples submitted to the same assays have therefore validated the proposed methods, and confirmed the wide commercialization of R. viburnoides in the state of Minas Gerais, Brazil.

14.
Braz J Biol ; 61(1): 63-7, 2001 Feb.
Artigo em Inglês, Português | MEDLINE | ID: mdl-11340463

RESUMO

In spite of the importance of the "uruçu" bee as honey producer of excellent quality, as well, potential pollinator both in agricultural and natural ecosystems, mainly in North-eastern Brazil, just some information is found in literature about sources that such bees utilize to collect nectar and pollen. The identification of the plants visited by Melipona scutellaris was accomplished with base on the analysis of pollen types found in the honey samples collected every two months, from March 1997 to February 1998, in 15 colonies located in Catu, State of Bahia, Brazil (12 degrees 21'00"S, 38 degrees 22'40"W, 76 m of altitude). Qualitative and quantitative analysis of the pollen types were carried out determining the percentage and occurrence classes. Twenty-eight pollen types were found, being considered dominant pollen, the Eucalyptus spp. and Psidium sp. types and secondary pollen, Bauhinia sp., Caesalpinia sp. and Mimosa verrucata types. It was verified dominant pollen of Eucalyptus spp. in honeys produced in November/December 1997 and January/February 1998. The families Caesalpiniaceae (14%), Mimosaceae (25%) and Myrtaceae (56%) were the most represented in the pollen spectrum.


Assuntos
Abelhas , Mel/análise , Plantas/classificação , Pólen/classificação , Animais , Estações do Ano , Análise Espectral
15.
Rev. bras. biol ; 61(1): 63-67, Feb. 2001. ilus, tab
Artigo em Inglês | LILACS | ID: lil-282400

RESUMO

In spite of the importance of the "uruçu" bee as honey producer of excellent quality, as well, potential pollinator both in agricultural and natural ecosystems, mainly in North-eastern Brazil, just some information is found in literature about sources that such bees utilize to collect nectar and pollen. The identification of the plants visited by Melipona scutellaris was accomplished with base on the analysis of pollen types found in the honey samples collected every two months, from March 1997 to February 1998, in 15 colonies located in Catu, State of Bahia, Brazil (12§21'00"S, 38§22'40"W, 76 m of altitude). Qualitative and quantitative analysis of the pollen types were carried out determining the percentage and occurrence classes. Twenty-eight pollen types were found, being considered dominant pollen, the Eucalyptus spp. and Psidium sp. types and secondary pollen, Bauhinia sp., Caesalpinia sp. and Mimosa verrucata types. It was verified dominant pollen of Eucalyptus spp. in honeys produced in November/December 1997 and January/February 1998. The families Caesalpiniaceae (14 percent), Mimosaceae (25 percent) and Myrtaceae (56 percent) were the most represented in the pollen spectrum


Assuntos
Animais , Mel/análise , Plantas/classificação , Pólen/classificação , Abelhas , Estações do Ano , Análise Espectral
16.
Rev. bras. anal. clin ; 30(4): 185-7, 1998. tab, graf
Artigo em Português | LILACS | ID: lil-246318

RESUMO

SÄo apresentados os resultados de 23 exames parasitológicos de fezes coletadas com conservador MIF e analisadas pelo método preconizado por Hoffman, Pons & Janer no Laboratório de Saúde Pública/FFB/UFJF e, de 9 análises bacteriológicas da água consumida na residência de 7 escolares da EMEI "Sant'Ana Itatiaia" - Juiz de Fora - MG, segundo a metodologia empregada no Laboratório de Análise de Alimentos e Saneamento de Aguas/FFB/UFJF. O estudo foi desenvolvido nos meses de Agosto a Outubro de 1994 em escolares com idade entre 4 e 6 anos e de ambos os sexos. A percentagem das amostras de fezes positivas foi de 56,52 porcento e a de negativas de 43,48 porcento. A etiologia das enteroparasitoses de maior incidência na populaçäo estudada foi: Entamoeba coli (38,89 porcento), Ascaris lumbricoides (27,78 porcento), Trichuris trichiura (11,11 porcento), Giardia lamblia (11,11 porcento) e Entamoeba histolytica (11,11 porcento). Das amostras analisadas, 17,39 porcento revelaram a presença de mais de um parasita. Apesar de näo ter sido possível correlacionar a etiologia das enteroparasitoses com uma provável veiculaçäo hídrica das mesmas, verificou-se que 61,11 porcento das amostras de fezes examinadas revelaram a presença de protozoários e, ainda, que 60 porcento das amostras de água oriundas de outras fontes que näo o abastecimento público, foram consideradas impróprias para o consumo como bebida. Tais dados reforçam a necessidade de medidas administrativas eficientes para a implantaçäo e melhoria do saneamento básico, pois näo existe saúde sem infra-estrutura sanitária


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Enteropatias Parasitárias/etiologia , Fezes/parasitologia , Infraestrutura Sanitária , Serviços de Saúde Escolar , Tricuríase , Consumo de Água (Saúde Ambiental) , Ascaris lumbricoides , Entamoeba histolytica , Eucariotos , Giardia lamblia , Incidência , Trichuris
17.
FEMS Immunol Med Microbiol ; 7(4): 297-301, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8136780

RESUMO

A study was carried out to evaluate the potential intestinal toxicity of 188 samples of Vibrio cholerae non-01 isolated from seawater found along the beaches of Rio de Janeiro city. Three different assays were carried out involving: (a) detection of vascular permeability factor (PF) in guinea pigs (together with assessment of two culture media for production of the toxin); (b) intestinal fluid accumulation (FA) in suckling mice; and (c) detection of haemolysin. The results demonstrated that both culture media gave a similar level of performance. In the animal assays, 43% of the samples induced PF in guinea pigs, 28.7% caused intestinal fluid accumulation in suckling mice, and 63.28% contained haemolysin. Only 4.25% of the samples gave positive results in all three tests.


Assuntos
Vibrio cholerae/patogenicidade , Animais , Fatores de Crescimento Endotelial/análise , Feminino , Cobaias , Proteínas Hemolisinas/análise , Mucosa Intestinal/metabolismo , Linfocinas/análise , Masculino , Camundongos , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Virulência
18.
Mem. Inst. Oswaldo Cruz ; 88(4): 589-92, Oct.-Dec. 1993. tab
Artigo em Inglês | LILACS | ID: lil-148846

RESUMO

Strains of Vibrio parahaemolyticus, Vibrio fluvialis and Vibrio mimicus isolated from seafood and seawater were examined for characteristics related to infectivity, such as enzymatic activity and animal assays. All strains hydrolysed DNA, starch, gelatin and chitin. Variable results were obtained with the haemolysin, chondroitin, collagen, elastin and lecithin tests. Production of thermostable direct haemolysin by V. parahaemolyticus was detected in 7.1 per cent strains derived from seafood and 2 per cent from seawater. In the animal assays, strains of V. fluvialis showed positive results at skin PF (75 per cent ), mouse lethality (100 per cent ), but no fluid accumulation in the suckling mice model was noted. Concerning V. mimicus, results showed skin PF (100 per cent ), mouse lethality (100 per cent ) and fluid accumulation in suckling mice (66.6 per cent )


Assuntos
Animais , Camundongos , Vibrio/patogenicidade , Microbiologia Ambiental , Vibrio parahaemolyticus/patogenicidade , Virulência
19.
Mem Inst Oswaldo Cruz ; 88(4): 589-92, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8139466

RESUMO

Strains of Vibrio parahaemolyticus, Vibrio fluvialis and Vibrio mimicus isolated from seafood and seawater were examined for characteristics related to infectivity, such as enzymatic activity and animal assays. All strains hydrolysed DNA, starch, gelatin and chitin. Variable results were obtained with the haemolysin, chondroitin, collagen, elastin and lecithin tests. Production of thermostable direct haemolysin by V. parahaemolyticus was detected in 7.1% strains derived from seafood and 2% from seawater. In the animal assays, strains of V. fluvialis showed positive results at skin PF (75%), mouse lethality (100%), but no fluid accumulation in the suckling mice model was noted. Concerning V. mimicus, results showed skin PF (100%), mouse lethality (100%) and fluid accumulation in suckling mice (66.6%).


Assuntos
Vibrio/patogenicidade , Animais , Microbiologia Ambiental , Camundongos , Vibrio parahaemolyticus/patogenicidade , Virulência
20.
J S Afr Vet Assoc ; 62(4): 171-5, 1991 Dec.
Artigo em Africano | MEDLINE | ID: mdl-1770493

RESUMO

A veld ram performance testing unit consists of an association of stud or commercial ram breeders, who compare the performance of selected rams under field conditions on common pastures. The best performers are subsequently auctioned at public sales. To date, at least 10 Merino veld ram clubs have been established in various centres in South Africa. A strain of Haemonchus contortus, which was isolated from the pastures of one of these performance testing units, was found to be resistant to ivermectin, oxfendazole and rafoxanide. Closantel, levamisole and disophenol were more than 99% effective. The wide dispersal of the rams after testing, constitutes a potential danger for dissemination of helminths with resistant genes. Precautionary methods should include careful routine monitoring of drug susceptibility on the communal pastures, on the farms of individual members and thorough deworming of rams before they leave the testing unit. The prevention and control of resistance in such testing units are discussed, but it is emphasised that this is difficult, particularly if the worm strains on the communal grazing have become resistant to some of the anthelmintic groups.


Assuntos
Anti-Helmínticos/farmacologia , Haemonchus/efeitos dos fármacos , Ovinos/parasitologia , Animais , Resistência a Medicamentos/genética , Hemoncose/tratamento farmacológico , Hemoncose/veterinária , Masculino , Doenças dos Ovinos/tratamento farmacológico
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