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1.
2.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1582-1590, set.-out. 2019. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1038681

RESUMO

Hemigrammus caudovittatus e Danio rerio foram expostos aos hipoglicemiantes orais (HOs) cloridrato de metformina a 40µg/L e 120µg/L e glibenclamida a 0,13µg/L e 0,39µg/L durante 100 dias. Foram avaliados os efeitos tóxicos dos fármacos em relação ao peso, ao comportamento animal, à glicemia e à mortalidade. H. caudovittatus expostos à menor concentração dos fármacos apresentaram aumento significativo (P<0,05) no evento Respiração Aérea. Ainda, foi observado aumento no comportamento Descansar quando os animais foram expostos à glibenclamida a 0,39µg/L. Em D. rerio expostos ao cloridrato de metformina a 120µg/L, foi observado aumento (P<0,05) no comportamento Descansar. A glibenclamida provocou redução (P<0,05) na glicemia de H. caudovittatus. Ambos os fármacos causaram efeito letal na espécie D. rerio, contudo a glibenclamida foi mais tóxica, causando 100% de mortalidade em 30 dias de exposição. Os animais que vieram a óbito apresentaram congestão nos arcos branquiais e hemorragia. Os HOs foram desenvolvidos para apresentarem efeitos fisiológicos em mamíferos, entretanto efeitos tóxicos foram encontrados nas duas espécies de peixe estudadas. Isso levanta a preocupação sobre possíveis efeitos tóxicos de HOs e sobre quais métodos serão utilizados para a sua degradação no ambiente aquático.(AU)


Hemigrammus caudovittatus and Danio rerio were exposed to oral hypoglycemic drugs (HOs) metformin hydrochloride at 40µg/L and 120µg/L and to glibenclamide at 0.13µg/L and 0.39µg/L during 100 days. Toxic effects of the drugs were evaluated based on weight, animal behavior, blood glucose and mortality. H. caudovittatus exposed to lowest concentration of the drugs showed significant increase (P< 0.05) in the Air breathing event. Furthermore, increase in Rest event was observed when animals were exposed to glibenclamide at 0.39µg/L. An increase (P< 0.05) in the frequency of Rest behavior in the D. rerio exposed to metformin hydrochloride at 120µg/L was observed. Glibenclamide caused decrease (P< 0.05) in the blood glucose of H. caudovittatus. Both drugs caused lethal effect against D. rerio. Nevertheless, glibenclamide was more toxic causing 100% of mortality after 30 days of exposure. The animals that died showed congestion on the branchial arches and hemorrhage. The HOs were developed to have physiological effects in mammals. However, toxic effects were found in both species of fish studied. This raises concerns about possible toxic effects of HOs and what methods will be used for their degradation in the aquatic environment.(AU)


Assuntos
Animais , Peixe-Zebra , Glibureto/toxicidade , Testes de Toxicidade/veterinária , Resíduos Químicos , Characidae , Hipoglicemiantes/toxicidade , Metformina/toxicidade , Modelos Animais
3.
Braz J Microbiol ; 50(1): 195-203, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30610494

RESUMO

The biotransformation of shrimp head waste into ingredients for Nile tilapia (Oreochromis niloticus) post-larvae (PLs) diet formulations was evaluated herein. A novel consortium of lactic acid bacteria, comprising the strains Lactobacillus futsaii LAB06 and L. plantarum LAB14, selected based on kinetic growth parameters, was applied in the fermentation of shrimp head waste. After 48 h, the highest lactic acid production was 100 g L-1, allowing for maximum recovery of chitin and protein-rich liquor. The liquor was added to commercial powdered fish feed at 15, 30, and 45% (w/w) and offered to Nile tilapia PL during 28 days. The inclusion of 30% provided the best results for Nile tilapia PL survival, weight and length gains, specific growth rate, and biomass, proving that the fermented liquor can be incorporated, leading to economic benefits and contributing to the reduction of environmental pollution caused by the improper disposal of shrimp waste.


Assuntos
Ciclídeos/metabolismo , Lactobacillus/metabolismo , Palaemonidae/microbiologia , Resíduos/análise , Ração Animal/análise , Ração Animal/microbiologia , Animais , Aquicultura , Biotransformação , Quitina/metabolismo , Ciclídeos/crescimento & desenvolvimento , Fermentação , Cabeça/microbiologia , Palaemonidae/crescimento & desenvolvimento
4.
Ultrasonics ; 58: 87-95, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25578371

RESUMO

A primary reciprocity-based method for calibration of hydrophone magnitude and phase sensitivity is proposed. The method starts determining the transmit transfer function of an auxiliary transducer, based on the self-reciprocity method and using a stainless steel cylinder as reflecting target. Afterwards, the hydrophone, to be calibrated, is positioned facing the auxiliary transducer. The pressure field waveform, calculated at the hydrophone spot and based on the transmit transfer function of an auxiliary transducer, is used together with the output end of cable voltage waveform signal from the hydrophone to yield the calibrated hydrophone sensitivity. The method was tested with two similar membrane hydrophones, at frequencies within the 1.0-7.0 MHz range, in steps of 1.0 MHz. Results for magnitude sensitivity agree, within a confidence level of 95%, with those from previous calibration of same hydrophones at the National Physical Laboratory, in the UK (Enor⩽1.0). Phase sensitivity results agree with literature reported ones concerning the achieved uncertainty. Additionally, the phase sensitivities measured at 5.0 MHz for two similar hydrophones and employing two distinct auxiliary transducers presented no statistical significant difference. The method yielded a relative expanded uncertainty (p=0.95) for the sensitivity magnitude ranging between 6.6 and 7.0%, and an expanded uncertainty (p=0.95) ranging between 12° and 17° for the phase sensitivity. The results obtained so far lead to conclude that the proposed hydrophone calibration method is a validated alternative to the different existing methods.


Assuntos
Ultrassonografia/instrumentação , Calibragem , Reprodutibilidade dos Testes , Transdutores
5.
Braz J Biol ; 73(2): 271-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23917554

RESUMO

Understanding variation in plant traits in heterogeneous habitats is important to predict responses to changing environments, but trait-environment associations are poorly known along ecological gradients. We tested the hypothesis that plant architectural complexity increases with habitat complexity along a soil fertility gradient in a Cerrado (Neotropical savanna) area in southeastern Brazil. Plant architecture and productivity (estimated as the total number of healthy infructescences) of Miconia albicans (SW.) Triana were examined in three types of vegetation which together form a natural gradient of increasing soil fertility, tree density and canopy cover: grasslands (campo sujo, CS), shrublands (cerrado sensu strico, CE) and woodlands (cerradão, CD). As expected, plants growing at the CS were shorter and had a lower branching pattern, whereas plants at the CD were the tallest. Unexpectedly, however, CD plants did not show higher architectural complexity compared to CE plants. Higher architectural similarity between CE and CD plants compared to similarity between CS and CE plants suggests reduced expression of functional architectural traits under shade. Plants growing at the CE produced more quaternary shoots, leading to a larger number of infructescences. This higher plant productivity in CE indicates that trait variation in ecological gradients is more complex than previously thought. Nematode-induced galls accounted for fruit destruction in 76.5% infructescences across physiognomies, but percentage of attack was poorly related to architectural variables. Our data suggest shade-induced limitation in M. albicans architecture, and point to complex phenotypic variation in heterogeneous habitats in Neotropical savannas.


Assuntos
Ecossistema , Desenvolvimento Vegetal/fisiologia , Plantas , Solo/química , Brasil , Fenótipo , Plantas/classificação , Plantas/parasitologia
6.
J Appl Microbiol ; 107(5): 1711-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19457035

RESUMO

AIMS: This study was carried out to test whether bacterial and archaeal populations, and products of fermentation in each compartment of collared peccary stomach, vary significantly with urea feeding. Bacteria and archaeal population variation among the four stomach compartments were also compared. METHODS AND RESULTS: Archaeal and bacterial communities in the forestomach of four individuals per treatment - peccaries fed diets with and without urea - were analysed at molecular level using PCR followed by denaturing gradient gel electrophoresis. Volatile fatty acids profiles in the three different compartments of the forestomach were also compared. The bacterial community composition varied considerably among each compartment and with urea provision, but no variation was observed between archaeal populations. Differences in bacterial communities between treatments - with and without urea - were greater than amongst stomach compartments. The acetate: propionate proportion decreased with urea provision in diet. Some differences in bacterial but not archaeal community composition were observed in each compartment of the collared peccary forestomach. CONCLUSIONS: There are some differences in bacterial but not archaeal populations in each compartment of collared peccary stomach. Use of urea in the diet of peccary can substantially modify the profile of volatile fatty acids released in its forestomach, but does not influence the archaeal community composition. Urea has an important effect on bacterial population DGGE profile present in the peccary's forestomach. SIGNIFICANCE AND IMPACT OF THE STUDY: These results demonstrate the ability of the collared peccary to use urea as source of nonprotein nitrogen, and confirm a hypothesis that the collared peccary has a digestive physiology more similar to ruminant than nonruminant animals.


Assuntos
Archaea/efeitos dos fármacos , Archaea/isolamento & purificação , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Suínos/microbiologia , Ureia/farmacologia , Ração Animal , Animais , Archaea/genética , Bactérias/genética , DNA Arqueal/genética , DNA Bacteriano/genética , Eletroforese em Gel de Ágar , Ácidos Graxos Voláteis/análise , Masculino , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Estômago/química , Estômago/microbiologia
7.
Bioresour Technol ; 100(3): 1297-303, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18922691

RESUMO

Spirulina is the most extensively used microalgae for animal and human nutrition mostly because of its high protein content, 60-65% on a dry weight basis. The drying is the most expensive operation. The aim of the study was to characterize drying of Spirulina platensis in thin layer. A Statistical model was applied to analyze the effects of independent variables (air temperature and loads of solids in the tray) on the response of solubility in acid medium. The analysis of phycocyanin content was determined at the best drying condition. The Spirulina isotherm data were adjusted through Guggenheim, Anderson and de Boer (GAB) and Brunauer, Emmett and Teller (BET) correlations. The nonlinear regression analysis of isotherms data showed that the GAB equation more effective adjusted the experimental data (R(2)>99% and E%<10%). Drying curves of Spirulina showed only a decreasing rate-drying period. The material load and the interaction between the air temperature and material load were significant effects (P0.05), and the best results of solubility in acid medium ( approximately 79%) occurred at 60 degrees C and 4 kg/m(2). In under these conditions the phycocyanin content was determined to be 12.6% of dried Spirulina.


Assuntos
Dessecação/métodos , Modelos Biológicos , Modelos Químicos , Spirulina/química , Água/química , Ar , Simulação por Computador , Temperatura Alta , Modelos Estatísticos , Reologia/métodos , Solubilidade
8.
J Colloid Interface Sci ; 303(2): 444-9, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16989850

RESUMO

We present results of an electrical impedance spectroscopy investigation of the evolution of the aggregation of methyl orange (MO) in pure aqueous solutions as the concentration of the dye is varied. By applying the constant phase element (CPE) approximation to model the electrical response of the MO solutions, we have verified that the formation of dimers and oligomers can be recognized by specific signatures in the loss and capacitive components of the dielectric response of the system. We interpret these well-defined changes in the dielectric properties of the solutions as a result of molecular rearrangements caused by the aggregation process that alter the current circulation pathways and the electric dipole distribution. The fact that these specific changes in the dielectric behavior coincide with critical concentrations where dimer and oligomer formation in pure aqueous MO solutions are known to occur suggests that electrical impedance spectroscopy can be a competitive technique for the investigation of aggregation behavior in dyes and surfactants.

9.
Rev Soc Bras Med Trop ; 34(5): 407-11, 2001.
Artigo em Português | MEDLINE | ID: mdl-11600905

RESUMO

The study was undertaken aiming at identifying bacteria from the county of Raposa in the state of Maranhão. The clinical sample was collected by using a swab and held in a Cary-Blair transport medium. Enrichment in alkaline peptone water, isolation in TCBS selective indicator medium and biochemical coding of species were used for laboratory processing. Fifty fisherman with age varying from 12-65 years took part on the study. Vibrio bacteria isolated in 21 subjects had been identified. There was a predominance of V. alginolyticus (66.6%) followed by V. parahaemolyticus (42.8%), and V. cholerae non-O1 (9.5%). Lesions predominated on lower limbs, presenting hyperhemia, swelling, secretion, and pain. Some species of gram-negative bacteria of the Serratia, Proteus, Escherichia, Citrobacter, Enterobacter associated to the vibrios were isolated, as well as other non-fermenting bacteria (30.9) and gram-positive bacteria of the genos Staphylococcus.


Assuntos
Exposição Ocupacional , Pele/lesões , Pele/microbiologia , Vibrio/isolamento & purificação , Brasil , Humanos , Testes de Sensibilidade Microbiana
10.
Rev Soc Bras Med Trop ; 29(3): 245-50, 1996.
Artigo em Português | MEDLINE | ID: mdl-8701044

RESUMO

With previously defined criteria of inclusion and previous consent, twenty six consecutive patients (19 to 64 years old), with upper digestive symptoms, were submitted to endoscopy, with biopsy, constant of eight samples of the antropyloric region (four of the anterior aspect and four of the posterior aspect). Two samples were been for culture; two for free urease test, two for smears; all gathered in adequate transport medium over refrigeration. Two samples immersed in formaline to 10% for histopathologic exam. 25/26 (96%) of the patients showed infection by H. pylori by means of one or more methods utilized. In 16/26 (61%), alterations were observed in endoscopy (gastric inflammation in eleven, peptic ulcer in two and ulcer scars in three cases). Of the patients with endoscopic gastric inflammation, presented positive as well as all (100%) bearers of scar or peptic ulcer. A close relationship was observed between the presence of H. pylori and chronic gastric inflammation 24/25 (96%). Histopathologic slices stained by hematoxilin-eosin was the test of highest diagnostic sensitivity 24/25 (96%), followed by urease test 23%25 (92%), stained smears 19/25 (76%) and culture 18/25 (72%). Our conclusion is that the prevalence of gastric infection for H. pylori in symptomatic patients is high, correlated with chronic gastric inflammation and ulcers. Histopathologic slices stained by hematoxilin-eosin and free urease test are the most sensitive indicators of the presence of H. pylori. This study should proceed for further elucidation of questions realised and include a control group of symptomatics individuals paired for sex and age.


Assuntos
Gastrite/diagnóstico , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Úlcera Gástrica/diagnóstico , Adulto , Biópsia , Brasil/epidemiologia , Doença Crônica , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Gastrite/epidemiologia , Gastrite/microbiologia , Gastroscopia , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Úlcera Gástrica/epidemiologia , Úlcera Gástrica/microbiologia
11.
Am J Trop Med Hyg ; 53(4): 380-5, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7485690

RESUMO

Enlarged regional lymph nodes have been reported to accompany the cutaneous lesions of Leishmania (Viannia) braziliensis (= L. braziliensis). A survey in Ceara State, Brazil indicated that 77% of persons (456 of 595) with parasitologically confirmed cutaneous leishmaniasis reported lymphadenopathy in addition to skin lesions. A group of 169 persons with recently diagnosed leishmaniasis and lymph nodes measuring > or = 2 cm in diameter (mean = 3.6 cm, maximum = 10.5 cm) underwent detailed clinical examination. Lymphadenopathy preceded the skin lesions in more than two-thirds of these, on the average by two weeks. Cultures of lymph node aspirates yielded Leishmania more frequently (86%) than cultures of aspirates of skin (53%) or biopsies of skin (74%). Parasites were isolated from the peripheral blood of one patient. Persons with lymphadenopathy gave a history of fever and had enlarged livers or spleens more often than a comparison group of 50 persons with cutaneous lesions but no lymphadenopathy. Persons with lymphadenopathy had more intense leishmanin skin reactions and lymphocyte proliferation following stimulation with specific antigens, whereas persons without lymphadenopathy had a higher frequency of previous infection. Isolates of parasites from both groups were identified as L. braziliensis. These data demonstrate the early spread of L. braziliensis beyond the skin and suggest differences in host immunity between persons with and without lymphadenopathy. Leishmaniasis braziliensis should be considered in cases of unexplained lymphadenopathy in endemic areas.


Assuntos
Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/patologia , Linfonodos/parasitologia , Doenças Linfáticas/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biópsia por Agulha , Brasil , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/complicações , Linfonodos/patologia , Doenças Linfáticas/patologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Pele/parasitologia , Pele/patologia , Testes Cutâneos
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