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1.
Oper Dent ; 47(5): 549-561, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36026699

RESUMO

This study aimed to evaluate the effect of desensitizing and conventional mouth rinses on dentin tubule occlusion. Dentin hypersensitivity was simulated by EDTA application for five minutes. The specimens were randomly allocated into the following groups: desensitizing mouth rinses (Colgate Sensitive, Elmex Sensitive Professional, Listerine Advanced Defense Sensitive, Sensodyne Cool Mint); conventional mouth rinses (Colgate Plax, Elmex Caries Protection, Listerine Anticaries, Sensodyne Pronamel); a negative control (C-: distilled water); and Clinpro XT Varnish was the positive control (C+). Subsequently, the specimens were submitted to an erosive or abrasive challenge (performed separately) and to an erosive/abrasive cycling for five days (n=10 for each challenge). After treatment, challenges, and cycling, the specimens were analyzed in an environmental scanning electron microscope to verify the number of open dentin tubules (ODTs), counted by using Image J software (National Institutes of Health, Bethesda, MD, USA). Data were analyzed by the Kruskal-Wallis, Friedman and Dunn tests, with Bonferroni correction (α=0.05). Groups did not differ at baseline (p>0.05). At the post-treatment, erosion and abrasion stages, C+ was the only group that showed a reduction in ODTs compared to C-(p<0.05). In the other groups, numbers did not differ significantly from C- (p>0.05). After cycling, none of the groups exhibited significant reduction in ODTs other than C- (p>0.05); however, C+, Listerine Anticaries, and Colgate Plax had a lower number of ODTs than Listerine Sensitive and Sensodyne Pronamel. No mouth rinse was able to promote significant occlusion of the dentin tubules after treatment and the challenges. C+ was the only product that effectively promoted tubular occlusion, but this effect did not withstand several erosive and abrasive challenges.


Assuntos
Dessensibilizantes Dentinários , Benzoatos , Dentina , Dessensibilizantes Dentinários/farmacologia , Dessensibilizantes Dentinários/uso terapêutico , Diaminas , Ácido Edético , Fluoretos , Microscopia Eletrônica de Varredura , Antissépticos Bucais/farmacologia , Antissépticos Bucais/uso terapêutico , Dodecilsulfato de Sódio , Fluoreto de Sódio , Água
2.
Mar Pollut Bull ; 140: 30-34, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30803647

RESUMO

Polycyclic aromatic hydrocarbons (PAH) have been reported as acetylcholinesterase (AChE) inibitors, although in vitro studies on PAH effects on AChE activity are scarce and have only been performed using electric eel brain extracts. Thus, this study investigated PAH effects on brain AChE activity in a tropical fish species in Southeastern Brazil, mullet (Mugil liza). Mullet specimens were obtained from Guanabara Bay (N = 20), Rio de Janeiro, Brazil. Brain AChE was extracted and exposed to an environmentally relevant concentration of Pyrene, Chrysene, Phenanthrene, and Naphthalene, and PAH metabolites, 2-Naphthol and 1-OH-Pyrene. AChE activity inhibition was observed, although no difference was observed between high- and low- molecular weight PAH. 2-Naphthol was a less potent AChE inhibitor than Naphthalene, albeit non-significantly. Further studies are required, since only one PAH concentration was used herein. Mullet brain extracts seem to be adequate to assess possible neurotoxic PAH effects on fish AChE.


Assuntos
Encéfalo/enzimologia , Inibidores da Colinesterase/toxicidade , Exposição Ambiental/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Smegmamorpha/metabolismo , Acetilcolinesterase/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Brasil , Ecotoxicologia/métodos , Proteínas de Peixes/antagonistas & inibidores , Proteínas de Peixes/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Clima Tropical , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
3.
Lasers Med Sci ; 34(3): 449-455, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30215185

RESUMO

To evaluate the effect of Er,Cr:YSGG laser, associated with fluoride application, on the prevention/control of dentin erosion. Dentin slabs were embedded in acrylic resin, flattened, and polished. Half of the specimens were previously eroded (10 min immersion in 1% citric acid solution) and half were kept sound. The specimens (n = 10 each substrate) were randomly allocated into the experimental groups, according to the following treatments: control (no treatment); APF gel (1.23% F, 1 min); Er,Cr:YSGG laser irradiation (P1: 0.25 W, 20 Hz, 2.8 J/cm2, tip S75, beam diameter of 750 µm, 1 mm away from the surface); Er,Cr:YSGG laser irradiation (P2: 0.50 W, 20 Hz, 5.7 J/cm2, tip S75, beam diameter of 750 µm, 1 mm away from the surface); APF gel + Er,Cr:YSGG laser P1 and; APF gel + Er,Cr:YSGG laser P2. Afterwards, the specimens underwent an erosion-remineralization cycling, consisting of a 5-min immersion into 0.3% citric acid, followed by 60-min exposure to artificial saliva. This procedure was repeated 4×/day, for 5 days. Surface loss (SL, in µm) was determined by optical profilometry. Specimens from each group were analyzed by environmental scanning electron microscopy (n = 3). Data were statistically analyzed (α = 0.05). For the eroded specimens, APF gel presented the lowest SL, being different from the control. For the sound specimens, none of the groups differed from the control, except for Er,Cr:YSGG laser P2, which presented the highest SL. When substrates were compared, only the eroded specimens of the control and APF + Er,Cr:YSGG laser P1 Groups showed higher SL. Selective structure removal was observed for the laser-treated groups. None of the Er,Cr:YSGG laser parameters were effective in the prevention/control dentin erosion. The laser was also unable to enhance the protection of fluoride against dentin erosion.


Assuntos
Fluoreto de Fosfato Acidulado/uso terapêutico , Dentina/efeitos dos fármacos , Progressão da Doença , Lasers de Estado Sólido/uso terapêutico , Erosão Dentária/tratamento farmacológico , Erosão Dentária/prevenção & controle , Animais , Bovinos , Dentina/ultraestrutura , Microscopia Eletrônica de Varredura
4.
Environ Monit Assess ; 190(9): 564, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30167796

RESUMO

Tropical coastal lagoons are highly productive environments exhibiting high biodiversity. However, the use of these ecosystems by local communities is of concern, since this generally leads to environmental degradation. The Imboassica coastal lagoon, located in Macaé city, in Northern Rio de Janeiro, is an important ecosystem in the state, however, already displaying signs of anthropogenic impacts. Carnivorous fish Hoplias malabaricus specimens were sampled from this impacted site, as well as from a reference area. Fish from Imboassica Lagoon presented lower condition factor, lower cholinesterase activity, and higher percentage of erythrocyte micronuclei when compared to fish from the reference site. Metals in fish from Imboassica Lagoon were always higher than Encantada Lagoon, with some seasonal differences, where some metals were higher in the rainy season compared to the dry season in muscle tissue, with the exception of Cu, Fe, Sr, and Zn; and in the liver, except for Ba, Cd, Cr, Ni, and Sr. Cr and Mn in the edible muscle portion of the fish were higher than the limits established by Brazilian and International legislations as permissible for human consumption, thus leading to concerns regarding public health risks for the local population that use fish as their main protein source.


Assuntos
Ecossistema , Exposição Ambiental/efeitos adversos , Peixes/metabolismo , Metais Pesados/metabolismo , Alimentos Marinhos/análise , Água do Mar , Poluentes Químicos da Água/metabolismo , Animais , Biomarcadores/metabolismo , Brasil , Colinesterases/metabolismo , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Eritrócitos , Humanos , Fígado/metabolismo , Micronúcleos com Defeito Cromossômico , Músculos/metabolismo , Chuva , Estações do Ano , Clima Tropical
5.
PLoS One ; 11(9): e0163317, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27655611

RESUMO

Acetylcholinesterase (AChE) is an important enzyme in the control of the neuronal action potential and sensitive to organophosphate inhibition. Brain fish AChE is less sensitive to organophosphate inhibition than AChE from terrestrial animals, although this sensitivity is variable among species and has not yet been fully evaluated in fish species. In this setting, inhibition kinetic constants for progressive irreversible inhibition of brain acetylcholinesterase due to methyl-paraoxon exposure were determined in three fish species (Mugil liza, Genidens genidens and Lagocephalus laevigatus) and hen (Gallus domesticus). Enzyme extraction using a detergent was shown to be adequate, and samples presented activity inhibition in high substrate concentrations and suppression of inhibition by methyl-paraoxon in the presence of the substrate, similar to kinetic patterns from purified enzyme preparations. Catfish (G. genidens) AChE presented the highest sensitivity among the evaluated fish species (IC50 = 1031.20 nM ± 63.17) in comparison to M. liza and L. laevigatus (IC50: 2878.83 ± 421.94 and 2842.5 ± 144.63 nM respectively). The lower dissociation constant (Kd = 20.3 ± 2.95 µM) of catfish AChE showed greater enzyme affinity for methyl-paraoxon, explaining this species higher sensitivity to organophosphates. Hen AChE presented higher ki (900.57 ± 65.3 mM-1min-1) and, consequently, greater sensitivity to methyl-paraoxon, explained by a lower Kd (0.6 ± 0.13 µM). Furthermore, hen AChE did not differentiate between the propionylthiocholine and acetylthiocholine substrates, indicating easier access of methyl-paraoxon to the hen enzyme activity site. The results obtained herein indicate a suitable extraction of AChE and, despite different inhibition kinetic constants, demonstrate that fish AChE is less sensitive to methyl-paraoxon, probably due to reduced access to the catalytic center which provides greater enzyme substrate selectivity.

6.
Lett Appl Microbiol ; 63(3): 183-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27416521

RESUMO

UNLABELLED: Paranaguá Bay is one of the largest estuarine systems on the Southern Brazilian coast. The only recorded cholera outbreak in this region since the early 20th century occurred in 1999 and resulted in 467 cases and at least three reported deaths in a population of approx. 150 000 people. This short communication reports historical, unpublished data related to that outbreak. Water, zooplankton and bivalve samples were collected and evaluated using direct fluorescence assay to determine whether Vibrio cholerae serogroups O1 and O139 were present in the estuarine system at that time. Most of the water (83%) and zooplankton samples (75%) were positive for V. cholerae O1, while V. cholerae O139 was not detected. Shellfish (Mytella sp.) were also positive for V. cholerae O1. These results indicate that the estuary, including biological vectors such as copepods and bivalves, comprise an important reservoir of V. cholerae O1 and a probable waterborne pathway for the disease, in addition to contamination with untreated sewage. SIGNIFICANCE AND IMPACT OF THE STUDY: Despite most of the cholera cases that occurred in Brazil during the 7th pandemic were located in the northern areas of the country, a significant outbreak in Paranaguá, an estuary in the south coast, resulted in at least three deaths in 1999. We report here the detection of Vibrio cholerae O1 in water, zooplankton and bivalve samples during the outbreak, using direct fluorescence assay as an alternative method for the traditional plate culture employed at the time by the Brazilian Sanitary Agency. Results demonstrate that aquatic natural reservoirs comprise a potential route of transmission of cholera, in addition to untreated sewage and routine monitoring is recommended.


Assuntos
Bivalves/microbiologia , Cólera/epidemiologia , Copépodes/microbiologia , Esgotos/microbiologia , Vibrio cholerae O1/isolamento & purificação , Zooplâncton/microbiologia , Animais , Brasil , Cólera/microbiologia , Estuários , Humanos , Pandemias , Microbiologia da Água
7.
Braz. j. biol ; 76(2): 279-291, Apr.-June 2016. ilus, graf, tab, map
Artigo em Inglês | VETINDEX | ID: vti-25501

RESUMO

Abstract This study evaluated changes in the community of rotifers and microcrustaceans associated with the construction of a large and dendritic reservoir in Iguaçu River (Brazil), as the last reservoir of a sequence of five cascading systems. Differences were clear between pre-filling and post-filling phases for organisms and some of environmental variables. In the pre-filling phase, the community was more homogeneous along the downstream river gradient, and spatial compartmentalization in the new reservoir was common during the post-filling phase. From 140 identified taxa, 10 species occurred exclusively in the pre-filling phase and 32 in the post-filling phase. After completion of the fifth reservoir filling-up, opportunistic, pioneer and fast-developing species quickly dominated, and downstream of the fourth reservoir the pre-filling decreasing gradient of richness, diversity and evenness disappeared. Richness of rotifers and cladocerans, cladocerans diversity, and evenness of rotifers, cladocerans and copepods were generally higher in the post-filling phase. A non-metric multidimensional analysis based on a presence/absence matrix depicted a homogeneous and dense group of species associated to the pre-filling phase and a second, dispersed group related to the post-filling phase. Spearman correlations pointed out significant positive effects of transparency on rotifer species richness in the post-filling phase, and negative effects on the microcrustacean richness in the pre-filling phase. Dam construction caused disruption of the downstream lotic gradient along the series of dams, leading to the development of distinct species in lentic spatial compartments.(AU)


Resumo Esse estudo analisou os efeitos da construção de um reservatório largo e dendrítico no Brasil sobre a comunidade de rotíferos e microcrustáceos, sendo o último reservatório de uma cascata de cinco. Houve claras diferenças entre as fases pré e pós-enchimento para os organismos e para algumas variáveis ambientais. Na fase pré-enchimento, a comunidade foi mais homogênea no gradiente longitudinal no rio a jusante, e na fase pós-enchimento houve compartimentalização espacial no novo reservatório. Dos 140 táxons identificados, dez espécies ocorreram exclusivamente na fase pré-enchimento e 32 na fase pós-enchimento. Após o enchimento, espécies oportunistas, pioneiras e de rápido desenvolvimento foram dominantes, e desapareceu o gradiente de decréscimo a jusante do quarto reservatório para a riqueza, diversidade e equitabilidade durante a fase pré-enchimento. A riqueza de rotíferos e cladóceros, a diversidade de cladóceros, e a equitabilidade de rotíferos, cladóceros e copépodes foram elevadas na fase pós-enchimento. A análise de escalonamento multidimensional não-métrico sobre a matriz de presença e ausência mostrou um grupo homogêneo e denso de espécies e meses de amostragem na fase pré-enchimento, e outro grupo disperso na fase pós-enchimento. Correlações de Spearman apontaram efeitos significativos da transparência sobre a riqueza de rotíferos na fase pós-enchimento, e efeitos negativos sobre a riqueza de microcrustáceos na outra fase. Os efeitos da construção do reservatório causaram rompimento no gradiente lótico contínuo a jusante do quarto reservatório observado na fase pré-enchimento, permitindo o desenvolvimento de espécies em compartimentos espaciais lênticos.(AU)


Assuntos
Animais , Cladocera/crescimento & desenvolvimento , Cladocera/fisiologia , Rotíferos/crescimento & desenvolvimento , Rotíferos/fisiologia , Corrente Jusante , Reservatórios de Água
8.
Braz. j. biol ; Braz. j. biol;76(2): 279-291, Apr.-June 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-781407

RESUMO

Abstract This study evaluated changes in the community of rotifers and microcrustaceans associated with the construction of a large and dendritic reservoir in Iguaçu River (Brazil), as the last reservoir of a sequence of five cascading systems. Differences were clear between pre-filling and post-filling phases for organisms and some of environmental variables. In the pre-filling phase, the community was more homogeneous along the downstream river gradient, and spatial compartmentalization in the new reservoir was common during the post-filling phase. From 140 identified taxa, 10 species occurred exclusively in the pre-filling phase and 32 in the post-filling phase. After completion of the fifth reservoir filling-up, opportunistic, pioneer and fast-developing species quickly dominated, and downstream of the fourth reservoir the pre-filling decreasing gradient of richness, diversity and evenness disappeared. Richness of rotifers and cladocerans, cladocerans diversity, and evenness of rotifers, cladocerans and copepods were generally higher in the post-filling phase. A non-metric multidimensional analysis based on a presence/absence matrix depicted a homogeneous and dense group of species associated to the pre-filling phase and a second, dispersed group related to the post-filling phase. Spearman correlations pointed out significant positive effects of transparency on rotifer species richness in the post-filling phase, and negative effects on the microcrustacean richness in the pre-filling phase. Dam construction caused disruption of the downstream lotic gradient along the series of dams, leading to the development of distinct species in lentic spatial compartments.


Resumo Esse estudo analisou os efeitos da construção de um reservatório largo e dendrítico no Brasil sobre a comunidade de rotíferos e microcrustáceos, sendo o último reservatório de uma cascata de cinco. Houve claras diferenças entre as fases pré e pós-enchimento para os organismos e para algumas variáveis ambientais. Na fase pré-enchimento, a comunidade foi mais homogênea no gradiente longitudinal no rio a jusante, e na fase pós-enchimento houve compartimentalização espacial no novo reservatório. Dos 140 táxons identificados, dez espécies ocorreram exclusivamente na fase pré-enchimento e 32 na fase pós-enchimento. Após o enchimento, espécies oportunistas, pioneiras e de rápido desenvolvimento foram dominantes, e desapareceu o gradiente de decréscimo a jusante do quarto reservatório para a riqueza, diversidade e equitabilidade durante a fase pré-enchimento. A riqueza de rotíferos e cladóceros, a diversidade de cladóceros, e a equitabilidade de rotíferos, cladóceros e copépodes foram elevadas na fase pós-enchimento. A análise de escalonamento multidimensional não-métrico sobre a matriz de presença e ausência mostrou um grupo homogêneo e denso de espécies e meses de amostragem na fase pré-enchimento, e outro grupo disperso na fase pós-enchimento. Correlações de Spearman apontaram efeitos significativos da transparência sobre a riqueza de rotíferos na fase pós-enchimento, e efeitos negativos sobre a riqueza de microcrustáceos na outra fase. Os efeitos da construção do reservatório causaram rompimento no gradiente lótico contínuo a jusante do quarto reservatório observado na fase pré-enchimento, permitindo o desenvolvimento de espécies em compartimentos espaciais lênticos.


Assuntos
Animais , Rotíferos/fisiologia , Zooplâncton/fisiologia , Rios , Estações do Ano , Brasil , Dinâmica Populacional , Densidade Demográfica , Aquicultura/métodos , Copépodes/fisiologia , Fenômenos Ecológicos e Ambientais , Hidrobiologia
9.
Braz J Biol ; 76(2): 279-91, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26983084

RESUMO

This study evaluated changes in the community of rotifers and microcrustaceans associated with the construction of a large and dendritic reservoir in Iguaçu River (Brazil), as the last reservoir of a sequence of five cascading systems. Differences were clear between pre-filling and post-filling phases for organisms and some of environmental variables. In the pre-filling phase, the community was more homogeneous along the downstream river gradient, and spatial compartmentalization in the new reservoir was common during the post-filling phase. From 140 identified taxa, 10 species occurred exclusively in the pre-filling phase and 32 in the post-filling phase. After completion of the fifth reservoir filling-up, opportunistic, pioneer and fast-developing species quickly dominated, and downstream of the fourth reservoir the pre-filling decreasing gradient of richness, diversity and evenness disappeared. Richness of rotifers and cladocerans, cladocerans diversity, and evenness of rotifers, cladocerans and copepods were generally higher in the post-filling phase. A non-metric multidimensional analysis based on a presence/absence matrix depicted a homogeneous and dense group of species associated to the pre-filling phase and a second, dispersed group related to the post-filling phase. Spearman correlations pointed out significant positive effects of transparency on rotifer species richness in the post-filling phase, and negative effects on the microcrustacean richness in the pre-filling phase. Dam construction caused disruption of the downstream lotic gradient along the series of dams, leading to the development of distinct species in lentic spatial compartments.


Assuntos
Copépodes/fisiologia , Rios , Rotíferos/fisiologia , Zooplâncton/fisiologia , Animais , Aquicultura/métodos , Brasil , Fenômenos Ecológicos e Ambientais , Hidrobiologia , Densidade Demográfica , Dinâmica Populacional , Estações do Ano
10.
Int Endod J ; 49(7): 700-5, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26174577

RESUMO

AIM: To evaluate the amount of apically extruded debris produced by ProTaper Universal (PTU), ProTaper Next (PTN), WaveOne (WO) and Reciproc (R) systems after large apical preparations. METHODOLOGY: Sixty mandibular premolars with a single canal were selected and randomly assigned into 4 groups (n = 15) according to the system used for root canal preparation: PTU, PTN, WO and R groups. Canal preparations were performed up to size 40 in each group. Distilled water was used as an irrigant, and the apically extruded debris from each tooth was collected in pre-weighted glass vials and dried. The average weight of debris was assessed using a microbalance, and the data were analysed statistically using one-way analysis of variance and the post hoc Tukey multiple comparison test (α = 0.05). RESULTS: The PTU system was associated with significantly more debris than the other systems (P < 0.05). No significant differences were found between PTN, WO and R systems (P > 0.05). CONCLUSIONS: All systems were associated with apical debris extrusion when canals were prepared to a large apical size. The PTU system was associated with more debris extrusion.


Assuntos
Preparo de Canal Radicular/instrumentação , Ápice Dentário/cirurgia , Dente Pré-Molar/cirurgia , Humanos , Preparo de Canal Radicular/métodos
11.
Eur J Cancer Care (Engl) ; 25(4): 668-74, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26087364

RESUMO

Oral mucositis is a painful condition that occurs in 80% of patients who undergo haematopoietic stem cell transplantation (HSCT). Our objective was to determine the impact of mucositis on quality of life (QoL) of patients subjected to HSCT treated with low-level laser therapy (LLLT). Patients were evaluated: (1) on the first day of treatment; (2) 5 days after autologous or 8 days after allogeneic transplantation; (3) once bone marrow had integrated; and (4) 30 days after discharge. Clinical evaluation was performed using the World Health Organization criteria; oral health QoL was measured using the Oral Health Impact Profile (OHIP-14); and mucositis symptoms with the Patient-Reported Oral Mucositis Symptom (PROMS) scale. The higher the score, the lower the patient's QoL. The OHIP-14 responses showed that at D + 5/D + 8, all domains had the highest scores, while at times 1 and 4, the scores were lower. In the PROMS scale, all domains scored worst at time 2, and the differences between the scores at the four times were statistically significant. The study has shown that QoL improves over time in patients undergoing LLLT therapy for mucositis prevention.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Terapia com Luz de Baixa Intensidade/métodos , Estomatite/radioterapia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Neoplasias Hematológicas/terapia , Hospitalização , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Saúde Bucal , Estudos Prospectivos , Qualidade de Vida , Adulto Jovem
12.
Braz. J. Biol. ; 76(2)2016.
Artigo em Inglês | VETINDEX | ID: vti-744832

RESUMO

Abstract This study evaluated changes in the community of rotifers and microcrustaceans associated with the construction of a large and dendritic reservoir in Iguaçu River (Brazil), as the last reservoir of a sequence of five cascading systems. Differences were clear between pre-filling and post-filling phases for organisms and some of environmental variables. In the pre-filling phase, the community was more homogeneous along the downstream river gradient, and spatial compartmentalization in the new reservoir was common during the post-filling phase. From 140 identified taxa, 10 species occurred exclusively in the pre-filling phase and 32 in the post-filling phase. After completion of the fifth reservoir filling-up, opportunistic, pioneer and fast-developing species quickly dominated, and downstream of the fourth reservoir the pre-filling decreasing gradient of richness, diversity and evenness disappeared. Richness of rotifers and cladocerans, cladocerans diversity, and evenness of rotifers, cladocerans and copepods were generally higher in the post-filling phase. A non-metric multidimensional analysis based on a presence/absence matrix depicted a homogeneous and dense group of species associated to the pre-filling phase and a second, dispersed group related to the post-filling phase. Spearman correlations pointed out significant positive effects of transparency on rotifer species richness in the post-filling phase, and negative effects on the microcrustacean richness in the pre-filling phase. Dam construction caused disruption of the downstream lotic gradient along the series of dams, leading to the development of distinct species in lentic spatial compartments.


Resumo Esse estudo analisou os efeitos da construção de um reservatório largo e dendrítico no Brasil sobre a comunidade de rotíferos e microcrustáceos, sendo o último reservatório de uma cascata de cinco. Houve claras diferenças entre as fases pré e pós-enchimento para os organismos e para algumas variáveis ambientais. Na fase pré-enchimento, a comunidade foi mais homogênea no gradiente longitudinal no rio a jusante, e na fase pós-enchimento houve compartimentalização espacial no novo reservatório. Dos 140 táxons identificados, dez espécies ocorreram exclusivamente na fase pré-enchimento e 32 na fase pós-enchimento. Após o enchimento, espécies oportunistas, pioneiras e de rápido desenvolvimento foram dominantes, e desapareceu o gradiente de decréscimo a jusante do quarto reservatório para a riqueza, diversidade e equitabilidade durante a fase pré-enchimento. A riqueza de rotíferos e cladóceros, a diversidade de cladóceros, e a equitabilidade de rotíferos, cladóceros e copépodes foram elevadas na fase pós-enchimento. A análise de escalonamento multidimensional não-métrico sobre a matriz de presença e ausência mostrou um grupo homogêneo e denso de espécies e meses de amostragem na fase pré-enchimento, e outro grupo disperso na fase pós-enchimento. Correlações de Spearman apontaram efeitos significativos da transparência sobre a riqueza de rotíferos na fase pós-enchimento, e efeitos negativos sobre a riqueza de microcrustáceos na outra fase. Os efeitos da construção do reservatório causaram rompimento no gradiente lótico contínuo a jusante do quarto reservatório observado na fase pré-enchimento, permitindo o desenvolvimento de espécies em compartimentos espaciais lênticos.

15.
J Dairy Sci ; 88(9): 3211-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16107411

RESUMO

Phenotypic characteristics, antimicrobial susceptibility, and genetic relationships were analyzed in 107 Staphylococcus aureus isolates recovered from cows with subclinical mastitis in Southeastern Brazil. Thirteen different biochemical patterns were detected among isolates. A predominant pattern represented by about 54% of the isolates was distributed among several herds. Isolates of distinct phenotypic profiles were also detected within a herd. Susceptibility to ampicillin, cefotaxime, cephalotin, chloramphenicol, erythromycin, gentamycin, kanamycin, nitrofurantoin, norfloxacin, ofloxacin, oxacillin, penicillin, rifampin, sulfamethoxazole-trimethoprim, tetracycline, trimethoprim, and vancomycin, determined by the disk diffusion method, was observed in 44.9% of isolates. On the other hand, 55.1, 7.4, and 2.8% of the strains were resistant to ampicillin/penicillin, tetracycline, and erythromycin, respectively. Genetic diversity was analyzed by pulsed-field gel electrophoresis using SmaI as the restriction enzyme. All isolates could be typed by pulsed-field gel electrophoresis, which identified 16 types and 24 subtypes. Type A and its subtypes comprised 54.2% of all isolates and were recovered from 6 of the 9 herds analyzed. Other types and subtypes were also found in multiple herds. Although multiple types and subtypes were found within a specific herd, a predominant type was frequently observed.


Assuntos
Farmacorresistência Bacteriana , Mastite Bovina/microbiologia , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/metabolismo , Animais , Brasil , Bovinos , Eletroforese em Gel de Campo Pulsado , Feminino , Fermentação , Variação Genética , Genótipo , Mastite Bovina/tratamento farmacológico , Testes de Sensibilidade Microbiana , Leite/microbiologia , Fenótipo , Staphylococcus aureus/genética
16.
Rev. bras. anal. clin ; 36(4): 213-215, 2004. tab, graf
Artigo em Português | LILACS | ID: lil-412802

RESUMO

O presente trabalho teve como objetivo avaliar o efeito de diferentes doses do flavonóide rutina sobre os níveis de lipídios no soro de coelhos machos e fêmeas da raça Nova Zelândia, com 55 dias de vida. De acordo com os resultados, o colesterol não diferiu estatisticamente nos machos, mas apresentou reduções significativas para as fêmeas. Com relação ao colesterol-HDL, as fêmeas não apresentaram alteraçõe e machos apresentaram reduções no grupo tratado 20mg/dia de rutina. Para triacilgliceróis, observou-se diferenças significativas nos grupos tratados com 60mg/dia de rutina.


Assuntos
Masculino , Feminino , Coelhos , HDL-Colesterol , Flavonoides/administração & dosagem , Lipídeos/sangue , Rutina , Triglicerídeos , Antioxidantes
17.
Rev. ciênc. farm ; 24(1): 27-32, 2003. tab, graf
Artigo em Português | LILACS | ID: lil-384498

RESUMO

Modelos com animais são usados para se pesquisar a toxicidade de fármacos, alimentos e novas substâncias com propriedades farmacológicas. Tem sido considerado que o consumo de flavonóides em alimentos é da ordem de 1g proveniente de vegetais, como frutas, leguminosas, etc. Com este objetivo, o presente trabalho avaliou os efeitos da rutina em diferentes doses, através das concentrações de proteínas, enzimas aspartato amino transferase (AST) e alanina amino transferase (ALT) em soro de coelhos. Alterações que ocorreram nos níveis séricos de proteína não foram estatisticamente significativos nos grupos e tempos avaliados para os machos e para as fêmeas. A atividade da AST também não representou diferença estatisticamente significativa. Já para ALT, observou-se variação apenas com 20mg de rutina para os machos nos tempos 0 e 28 dias. Através dos resultados obtidos, pode-se concluir que a rutina não causou patologias hepáticas.


Assuntos
Animais , Masculino , Feminino , Alanina Transaminase , Aspartato Aminotransferases/administração & dosagem , Coelhos , Rutina
18.
Rev. bras. anal. clin ; 34(4): 213-219, 2002. graf
Artigo em Português | LILACS | ID: lil-506338

RESUMO

O presente trabalho teve como objetivo avaliar o efeito de diferentes dosagens de monascus sobre os constituintes sanguíneos, em coelhos da raça Nova Zelãndia, com 55 dias de vida para verificar o seu efeito hipolipidêmico e sua inocuidade nos parâmetros sanguíneos. Os resultados evidenciaram uma redução nos níveis de colesterol total nas fêmeas e um aumento nos triacilgliceróis, na dose de 100 mg da substãncia. Os níveis de albumina e creatinina, mostraram alterações estatisticamente significativas em todos os grupos e tempos considerados, mas nenhuma alteração foi observada nos valores médios de uréia e glicose, proteína sérica, cálcio e HDL-colesterol. Os resultados encontrados para bilirrubina total não indicaram efeito toxicológico das substãncias testadas. Os níveis de Gama-GT aumentou para a dose de 100 mg de monascus nas fêmeas e permaneceram inalterados nos machos. O aumento dos níveis de cloro podem ser considerados irrelevantes. As fêmeas que receberam 40 mg de monascus apresetnaram níveis aumentados de TGP, sendo que níveis séricos de fósforo não apresentaram flutuações.


The aim of this study was to test the effect of different doses of monascus, in rabbits, in order to verify hipolipydaemic effects in the blood serum parameters. The results showed a reduction of total cholesterol in the femaled and an increase of the triacilgliceróis, in the dose of 100 mg of monascus. The albumin and creatinin levels, showed statiscally signficant alterations in all the groups and times...


Assuntos
Animais , Coelhos , Experimentação Animal , Alternativas aos Testes com Animais , Análise Química do Sangue , Colesterol , HDL-Colesterol , Monascus , Toxicologia , Triglicerídeos , Alanina Transaminase , Albuminas , Bilirrubina , Proteínas Sanguíneas , Cálcio , Cloro , Creatinina , Glucose , Fósforo , Ureia
19.
Arq. bras. med. vet. zootec ; 53(1): 71-77, fev. 2001. tab, graf
Artigo em Português | VETINDEX | ID: vti-7407

RESUMO

Este trabalho objetivou relacionar o diâmetro da vesícula embrionária/fetal (DVE) e comprimento craniocaudal do embrião/feto (CCC) do 15§ ao 45§ dia de gestação com a idade de gestação em ovelhas. Utilizaram-se 19 ovelhas adultas da raça Bergamácia, com cio sincronizado e cobertas por um mesmo reprodutor. A avaliação ultra-sonográfica foi realizada diariamente do 15§ ao 30§ dia após a cobrição e a cada cinco dias do 30§ ao 45§ dia, utilizando-se aparelho com transdutor linear de 5,0 e 7,5MHZ. O crescimento diário médio do DVE e CCC foi de 1,40mm e 1,33mm, respectivamente. A calibragem inversa obtida para DVE foi: Dias = -11 + 50(0,1 + 0,04log DVE sobrescrito) 1/2(sobrescrito), com R2(sobrescrito) = 0,85 e para CCC foi: Dias = 13,63 + 12,5(-0,71 + 0,l6CCC)1/2(sobrescrito), com R 2 sobrescrito = 0,93. Tanto o DVE como o CCC obtidos por ultra-sonografia são medidas pelas quais se pode prever a idade de gestação em ovelhas da raça Bergamácia (AU)


This study aimed to relate embryonic/fetal vesicle diameter (EVD) and crown-rump length (CRL) to gestational age in ewes from the 15th to the 45th day of pregnancy. Nineteen adult Bergamácia ewes with synchronized estrus were mated by the same male. Ultrasonographic evaluations were performed every 24 hours from the 15th to the 30th day after mating and every five days from the 30th to the 45th day using 5.0 and 7.5MHZ linear transducers. Average daily growth of EVD and CRL were 1.40mm and 1.33mm, respectively. The inverse calibration obtained for EVD was: Days = -11 + 50(0.1 + 0.04log EVD)1/2 with R2 = 0.85, and for CRL was: Days = 13.63 + 12.5(- 0.71 + 0.16CRL)1/2 with R2 = 0.93. Both EVD and CRL obtained by ultrasonography are useful measurements that allow the prediction of gestational age in Bergamácia ewes(AU)


Assuntos
Animais , Ultrassonografia , Prenhez , Estatura Cabeça-Cóccix , Desenvolvimento Embrionário e Fetal/fisiologia , Ovinos
20.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);53(1): 71-7, fev. 2001. ilus, tab
Artigo em Português | LILACS | ID: lil-290499

RESUMO

Este trabalho objetivou relacionar o diâmetro da vesícula embrionária/fetal (DVE) e comprimento craniocaudal do embriäo/feto (CCC) do 15§ ao 45§ dia de gestaçäo com a idade de gestaçäo em ovelhas. Utilizaram-se 19 ovelhas adultas da raça Bergamácia, com cio sincronizado e cobertas por um mesmo reprodutor. A avaliaçäo ultra-sonográfica foi realizada diariamente do 15§ ao 30§ dia após a cobriçäo e a cada cinco dias do 30§ ao 45§ dia, utilizando-se aparelho com transdutor linear de 5,0 e 7,5MHZ. O crescimento diário médio do DVE e CCC foi de 1,40mm e 1,33mm, respectivamente. A calibragem inversa obtida para DVE foi: Dias = -11 + 50(0,1 + 0,04log DVE sobrescrito) 1/2(sobrescrito), com R2(sobrescrito) = 0,85 e para CCC foi: Dias = 13,63 + 12,5(-0,71 + 0,l6CCC)1/2(sobrescrito), com R 2 sobrescrito = 0,93. Tanto o DVE como o CCC obtidos por ultra-sonografia säo medidas pelas quais se pode prever a idade de gestaçäo em ovelhas da raça Bergamácia


Assuntos
Animais , Feminino , Estatura Cabeça-Cóccix , Prenhez , Ultrassonografia
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