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1.
Regul Toxicol Pharmacol ; 143: 105459, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37474097

RESUMO

The unexpected finding of N-nitrosamine (NA) impurities in many pharmaceutical products raised significant challenges for industry and regulators. In addition to well-studied small molecular weight NAs, many of which are potent rodent carcinogens, novel NAs associated with active pharmaceutical ingredients have been found, many of which have limited or no safety data. A tiered approach to establishing Acceptable Intake (AI) limits for NA impurities has been established using chemical-specific data, read-across, or a class-specific TTC limit. There are ∼140 NAs with some rodent carcinogenicity data, but much of it is older and does not meet current guidelines for what constitutes a 'robust' bioassay. Nevertheless, these data are an important source of information to ensure the best science is used for assessing NA impurities and assuring consumer safety while minimizing impact that can lead to drug shortages. We present several strategies to maximize the use of imperfect data including using a lower confidence limit on a rodent TD50, and leveraging data from multiple NAs. Information on the chemical structure known to impact potency can also support development of an AI or potentially conclude that a particular NA does not fall in the cohort of concern for potent carcinogenicity.


Assuntos
Mutagênicos , Nitrosaminas , Mutagênicos/toxicidade , Mutagênicos/química , Contaminação de Medicamentos , Medição de Risco , Carcinógenos/toxicidade , Carcinógenos/química , Preparações Farmacêuticas
2.
Nature ; 528(7580): 119-22, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26595275

RESUMO

Drought threatens tropical rainforests over seasonal to decadal timescales, but the drivers of tree mortality following drought remain poorly understood. It has been suggested that reduced availability of non-structural carbohydrates (NSC) critically increases mortality risk through insufficient carbon supply to metabolism ('carbon starvation'). However, little is known about how NSC stores are affected by drought, especially over the long term, and whether they are more important than hydraulic processes in determining drought-induced mortality. Using data from the world's longest-running experimental drought study in tropical rainforest (in the Brazilian Amazon), we test whether carbon starvation or deterioration of the water-conducting pathways from soil to leaf trigger tree mortality. Biomass loss from mortality in the experimentally droughted forest increased substantially after >10 years of reduced soil moisture availability. The mortality signal was dominated by the death of large trees, which were at a much greater risk of hydraulic deterioration than smaller trees. However, we find no evidence that the droughted trees suffered carbon starvation, as their NSC concentrations were similar to those of non-droughted trees, and growth rates did not decline in either living or dying trees. Our results indicate that hydraulics, rather than carbon starvation, triggers tree death from drought in tropical rainforest.


Assuntos
Carbono/metabolismo , Secas , Floresta Úmida , Árvores/metabolismo , Clima Tropical , Água/metabolismo , Biomassa , Tamanho Corporal , Brasil , Metabolismo dos Carboidratos , Folhas de Planta/metabolismo , Caules de Planta/metabolismo , Estações do Ano , Solo/química , Árvores/crescimento & desenvolvimento , Xilema/metabolismo
3.
Genet Mol Res ; 13(1): 1672-8, 2014 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-24535902

RESUMO

Among the many implications of climatic change on agriculture, drought is expected to continue to have a major impact on agribusinesses. Leaf curling is an anatomical characteristic that might be potentially used to enhance plant tolerance to water deficit. Hence, we aimed to study the genetic control of leaf curl in maize. From 2 contrasting inbred lines for the trait, generations F1, F2, and the backcrosses were obtained. All of these generations were evaluated in a randomized block design with 2 replicates. Leaf curl samples were collected from 3 leaves above the first ear at the tasseling stage, and quantified by dividing the width of the leaf blade with natural curling against its extended width. The mean and variance components were estimated by the weighted least square method. It was found that the trait studied has predominance of the additive effects, with genetic control being attributed to few genes that favor selection and exhibit minimal influence from the environment.


Assuntos
Folhas de Planta/genética , Locos de Características Quantitativas/genética , Zea mays/genética , Secas , Fenótipo , Folhas de Planta/anatomia & histologia , Água/metabolismo
4.
Dent Mater ; 38(8): 1404-1418, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35787894

RESUMO

OBJECTIVE: Evaluate the effect of different restorative filling techniques on the residual shrinkage stress (ShrS), cuspal strain (CS), depth of cure (DC), and enamel crack formation (Ec) in molars with MOD restorations. METHODS: Post-gel shrinkage, elastic modulus, compressive and diametral tensile strength of the Filtek One Bulk Fill composite were calculated. Sixty molars with MOD preparations were restored using four filling techniques: Bulk; Horizontal; Oblique; Natural enamel and dentin substitution (NEDS) technique. CS was measured using a strain gauge (n = 10). The DC (n = 5) was measured using Knoop hardness. Shrinkage stress/strain was analyzed using 3D finite element analysis. The Ec analysis was carried out by transillumination. Two-way ANOVA with repeated measures and Tukey's HSD test (α = 0.05) was performed for the CS data. Two-Way ANOVA and Tukey's HSD test was performed for the DC data (α = 0.05). RESULTS: CS was higher at the lingual cusp for the horizontal and NEDS technique. No statistical difference was found between the buccal and lingual CS values for the Bulk (p = 0.367) or Oblique techniques (p = 0.192). CS values were lower for the Bulk. More enamel cracks were found for the Bulk. DC was lower at 4 mm regardless the filling technique. The Horizontal showed the highest ShrS values. The Bulk generated the lower ShrS values. SIGNIFICANCE: A Bulk technique caused the lowest shrinkage stress/strain. An Oblique technique yielded the best balance between stress, strain and crack formation. NEDS technique is a good alternative to decrease the number of increments while maintaining the stress levels nearby the Oblique technique.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Esmalte Dentário , Restauração Dentária Permanente/métodos , Análise do Estresse Dentário , Teste de Materiais , Dente Molar , Polimerização
5.
Tree Physiol ; 42(3): 537-556, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-34508606

RESUMO

Future climate change predictions for tropical forests highlight increased frequency and intensity of extreme drought events. However, it remains unclear whether large and small trees have differential strategies to tolerate drought due to the different niches they occupy. The future of tropical forests is ultimately dependent on the capacity of small trees (<10 cm in diameter) to adjust their hydraulic system to tolerate drought. To address this question, we evaluated whether the drought tolerance of neotropical small trees can adjust to experimental water stress and was different from tall trees. We measured multiple drought resistance-related hydraulic traits across nine common neotropical genera at the world's longest-running tropical forest throughfall-exclusion experiment and compared their responses with surviving large canopy trees. Small understorey trees in both the control and the throughfall-exclusion treatment had lower minimum stomatal conductance and maximum hydraulic leaf-specific conductivity relative to large trees of the same genera, as well as a greater hydraulic safety margin (HSM), percentage loss of conductivity and embolism resistance, demonstrating that they occupy a distinct hydraulic niche. Surprisingly, in response to the drought treatment, small trees increased specific hydraulic conductivity by 56.3% and leaf:sapwood area ratio by 45.6%. The greater HSM of small understorey trees relative to large canopy trees likely enabled them to adjust other aspects of their hydraulic systems to increase hydraulic conductivity and take advantage of increases in light availability in the understorey resulting from the drought-induced mortality of canopy trees. Our results demonstrate that differences in hydraulic strategies between small understorey and large canopy trees drive hydraulic niche segregation. Small understorey trees can adjust their hydraulic systems in response to changes in water and light availability, indicating that natural regeneration of tropical forests following long-term drought may be possible.


Assuntos
Secas , Árvores , Mudança Climática , Florestas , Folhas de Planta/fisiologia , Árvores/fisiologia
6.
J Med Entomol ; 58(3): 1134-1137, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33295966

RESUMO

The aim of the present study was to describe the morphology of the eggs of Culex (Culex) saltanensis Dyar that occurs in the Neotropical region. Eggs of the Cx. (Cux.) saltanensis were collected at the Mata Atlântica FIOCRUZ campus, fixed in 1% osmium tetroxide, prepared for mounting on metal supports, observed under a scanning electron microscope, and described morphologically. The eggs had a coniform shape with a length of approximately 0.5 mm (505-510 µm) and a width in the median portion of 117 µm (113-123 µm). Upper portion is lined with tubers of irregular shape and varying sizes (0.64-1.31 µm), located on a cross-linked matrix forming bands observed under optical microscopy. The micropyle is encased in a necklace of approximately 6.6-µm plates arranged in a flower-like shape. Comparing Cx. (Cux.) saltanensis eggs with several species of different genera, important divergent characteristics can be observed. However, this study points to the need for new descriptions of eggs of species belonging to the same subgenus in order to analyze if there will be differences between them. Culex (Cux.) saltanensis eggs have particular characteristics not observed in eggs of other Culicidae genera.


Assuntos
Culex/ultraestrutura , Óvulo/ultraestrutura , Animais , Brasil , Culex/crescimento & desenvolvimento , Óvulo/crescimento & desenvolvimento
7.
New Phytol ; 187(3): 608-21, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20553394

RESUMO

*The effects of drought on the Amazon rainforest are potentially large but remain poorly understood. Here, carbon (C) cycling after 5 yr of a large-scale through-fall exclusion (TFE) experiment excluding about 50% of incident rainfall from an eastern Amazon rainforest was compared with a nearby control plot. *Principal C stocks and fluxes were intensively measured in 2005. Additional minor components were either quantified in later site measurements or derived from the available literature. *Total ecosystem respiration (R(eco)) and total plant C expenditure (PCE, the sum of net primary productivity (NPP) and autotrophic respiration (R(auto))), were elevated on the TFE plot relative to the control. The increase in PCE and R(eco) was mainly caused by a rise in R(auto) from foliage and roots. Heterotrophic respiration did not differ substantially between plots. NPP was 2.4 +/- 1.4 t C ha(-1) yr(-1) lower on the TFE than the control. Ecosystem carbon use efficiency, the proportion of PCE invested in NPP, was lower in the TFE plot (0.24 +/- 0.04) than in the control (0.32 +/- 0.04). *Drought caused by the TFE treatment appeared to drive fundamental shifts in ecosystem C cycling with potentially important consequences for long-term forest C storage.


Assuntos
Carbono/metabolismo , Secas , Árvores/metabolismo , Bactérias/metabolismo , Brasil , Dióxido de Carbono/metabolismo , Respiração Celular , Ecossistema , Solo , Fatores de Tempo
8.
Genet Mol Res ; 8(2): 577-88, 2009 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-19551646

RESUMO

Genetic models of sex and caste determination in eusocial stingless bees suggest specific patterns of male, worker and gyne cell distribution in the brood comb. Conflict between queen and laying workers over male parentage and center-periphery gradients of conditions, such as food and temperature, could also contribute to non-random spatial configuration. We converted the positions of the hexagonal cells in a brood comb to Cartesian coordinates, labeled by sex or caste of the individuals inside. To detect and locate clustered patterns, the mapped brood combs were evaluated by indexes of dispersion (MMC, mean distance of cells of a given category from their centroid) and eccentricity (DMB, distance between this centroid and the overall brood comb centroid) that we developed. After randomizing the labels and recalculating the indexes, we calculated probabilities that the original values had been generated by chance. We created sets of binary brood combs in which males were aggregated, regularly or randomly distributed among females. These stylized maps were used to describe the power of MMC and DMB, and they were applied to evaluate the male distribution in the sampled Nannotrigona testaceicornis brood combs. MMC was very sensitive to slight deviations from a perfectly rounded clump; DMB detected any asymmetry in the location of these compact to fuzzy clusters. Six of the 82 brood combs of N. testaceicornis that we analyzed had more than nine males, distributed according to variations in spatial patterns, as indicated by the two indexes.


Assuntos
Himenópteros/fisiologia , Comportamento de Nidação , Animais , Feminino , Masculino , Reprodução/fisiologia
9.
Transplant Proc ; 50(3): 819-823, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29661445

RESUMO

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) consists of the intravenous infusion of healthy hematopoietic stem cells to restore the medullary and immunologic function of patients affected by a series of hematologic, oncologic, immunologic, malignant and nonmalignant inherited or acquired diseases, with the possibility of cure or increase of disease-free survival. OBJECTIVE: To characterize the epidemiologic profile and the cases of death of patients who underwent HSCT. METHODS: This is a cohort quantitative study, nested with a retrospective, descriptive, and analytical study of a hospital-based cohort that included the patients who underwent HSCT at a referral service in the state of Rio Grande do Norte, a region of northeastern Brazil. RESULTS: There was a slight male prevalence (52.94%), the age of the patients ranged from 2 to 73 years old, 18.38% were brown, 47.06% were married, 15.07% were students, 78.31% had a diagnosis of multiple myeloma, 93.38% developed gastrointestinal toxicities, all patients received chemotherapeutic treatment, 54.78% had allogeneic HSCT, and the cause of the most recorded deaths was septic shock (48.19%). CONCLUSIONS: This study showed relevant scientific evidence on the clinical and epidemiologic profile of patients who underwent HSCT. In general, sociodemographic data are similar to national and international research results.


Assuntos
Transplante de Células-Tronco Hematopoéticas/estatística & dados numéricos , Mieloma Múltiplo/epidemiologia , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Prevalência , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
10.
Neurosci Lett ; 416(3): 227-30, 2007 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-17383094

RESUMO

Experimental manipulations suggest that in vivo administration of exogenous antioxidants agents decreases the concentration of free radical in the brain. Neurochemical studies have proposed a role for catalase in brain mechanisms responsible by development to status epilepticus (SE) induced by pilocarpine. The present study was aimed at was investigating the changes in catalase activities after pilocarpine-induced SE. Animals were treated with vitamin E (VIT E) 200 mg/kg (intraperitoneally (i.p.)) and, 30 min later, they received pilocarpine hydrochloride, 400 mg/kg, subcutaneous (s.c.) (P400). Other three groups received VIT E (200 mg/kg, i.p.), pilocarpine (400 mg/kg, s.c.) or 0.9% NaCl (control) alone. Animals were closely observed for behavioral changes, tremors, stereotyped movements, seizures, SE and death, for 24 h following the pilocarpine injection. The brains were dissected after decapitation. The results have shown that pilocarpine administration and resulting SE produced a significant increase in hippocampal catalase activity of (88%). In the group pre-treated which VIT E in hippocampal catalase activity was increase of 67% and 214% when compared with P400 and control group, respectively. Our results demonstrated a direct evidence of an increase in the activity of the hippocampal catalase of rat adults during seizure activity and after the pre-treated which VIT E that could be responsible by regulation of free radical levels during the establishment of SE.


Assuntos
Catalase/metabolismo , Hipocampo/efeitos dos fármacos , Pilocarpina , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/patologia , Vitamina E/farmacologia , Animais , Modelos Animais de Doenças , Interações Medicamentosas , Ativação Enzimática/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Tempo de Reação/efeitos dos fármacos , Estado Epiléptico/metabolismo , Estado Epiléptico/prevenção & controle , Vitamina E/uso terapêutico
11.
Neotrop Entomol ; 46(5): 499-506, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28185208

RESUMO

The Camponotus Mayr genus of carpenter ants is one of the largest in species number and widely represented in the Neotropical Region. Most species are generalists and capable of exploiting diverse habitats including urban environments. Urban green areas can act as a repository of regional biodiversity, thus we investigated whether this is valid for the largest city in South America. We compared the richness of Camponotus spp. in two green areas in regions with distinct urbanization profiles and also with previous surveys made in smaller cities and in natural areas of the original Atlantic Forest. Besides the usual capture of worker specimens, we included capture of alates to improve the species richness sampling. Morphological identification of Camponotus spp. is challenging, even more when alates are included. To assist in specimen identification, we performed DNA sequencing of mitochondrial and nuclear markers. The richness observed in the less stressed urban area was higher than in the more stressed one. Camponotus spp. reported in natural areas are largely represented in the urban area. DNA sequencing for specimen identification is hampered by the lack of corresponding sequences in the GenBank, but it helped to associate workers and alates of the same species and indicated the existence of cryptic species in the genus. Capture of alates allowed detection of several species for which workers were not sampled; therefore, it is a valuable tool for surveying diversity of Camponotus or other ant taxa with arboreal or hypogeic habits.


Assuntos
Formigas/classificação , Formigas/genética , Variação Genética , Genética Populacional , Animais , Brasil , Cidades , Ecossistema , Análise de Sequência de DNA
12.
Neurosci Lett ; 383(1-2): 165-70, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15876489

RESUMO

Behavioural changes, muscarinic and dopaminergic receptors density and levels of monoamines were measured in striatum of rats after pilocarpine-induced status epilepticus (SE). Wistar rats at the age of 21 days were treated with pilocarpine (400mg/kg; subcutaneously) whilst the control group was treated with 0.9% saline (s.c.). Both groups were sacrificed 1h following the treatment. SE induced a muscarinic receptor downregulation of 64% in pilocarpine group. This effect was also observed to be 57% in D(1) and 32% in D(2). In the dissociation constant (K(d)) values in muscarinic and D(1) receptor no alterations were verified. On the other hand, the K(d) value for D(2) was observed to increase 41%. High performance liquid chromatography determinations showed 63, 35, 77 and 64% decreases in dopamine, 3-methoxy-phenylacetic acid, serotonin and 5-hydroxyindoleacetic acid contents, respectively. The homovanilic acid level was verified to increase 119%. The noradrenaline content was unaltered. A direct evidence of monoamine levels alterations can be verified during seizure activity and receptor density changes appear to occur in an accentuated way in immature brain during the estabilishment of SE induced by pilocarpine.


Assuntos
Monoaminas Biogênicas/metabolismo , Corpo Estriado/efeitos dos fármacos , Pilocarpina , Receptores Dopaminérgicos/metabolismo , Receptores Muscarínicos/metabolismo , Estado Epiléptico/induzido quimicamente , Análise de Variância , Animais , Animais Recém-Nascidos , Comportamento Animal/efeitos dos fármacos , Benzazepinas/farmacocinética , Corpo Estriado/metabolismo , Antagonistas de Dopamina/farmacocinética , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , N-Metilescopolamina/farmacocinética , Ensaio Radioligante/métodos , Ratos , Ratos Wistar , Receptores Dopaminérgicos/classificação , Receptores Muscarínicos/classificação , Estado Epiléptico/metabolismo , Trítio/farmacocinética
13.
Neurosci Lett ; 385(3): 184-8, 2005 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-15967574

RESUMO

Levetiracetam (LEV) is a new antiepileptic drug effective as adjunctive therapy for partial seizures. It displays a unique pharmacological profile against experimental models of seizures, including pilocarpine-induced seizures in rodents. Aiming to clarify if anticonvulsant activity of LEV occurs due to cholinergic alterations, adult male mice received LEV injections before cholinergic agonists' administration. Pretreatment with LEV (30-200 mg/kg, i.p.) increased the latencies of seizures, but decreased status epilepticus and death on the seizure model induced by pilocarpine, 400 mg/kg, s.c. (P400). LEV (LEV200, 200 mg/kg, i.p.) pretreatment also reduced the intensity of tremors induced by oxotremorine (0.5 mg/kg, i.p). [3H]-N-methylscopolamine-binding assays in mice hippocampus showed that LEV200 pretreatment reverts the downregulation on muscarinic acetylcholine receptors (mAChR), induced by P400 administration, bringing back these density values to control ones (0.9% NaCl, i.p.). However, subtype-specific-binding assays revealed that P400- and LEV-alone treatments result in M1 and M2 subtypes decrease, respectively. The agonist-like behavior of LEV on the inhibitory M2 mAChR subtype, observed in this work, could contribute to explain the reduction on oxotremorine-induced tremors and the delay on pilocarpine-induced seizures, by an increase in the attenuation of neuronal activity mediated by the M1 receptors.


Assuntos
Anticonvulsivantes/uso terapêutico , Hipocampo/efeitos dos fármacos , Piracetam/análogos & derivados , Receptores Muscarínicos/efeitos dos fármacos , Convulsões/prevenção & controle , Animais , Convulsivantes/toxicidade , Modelos Animais de Doenças , Hipocampo/metabolismo , Levetiracetam , Masculino , Camundongos , Agonistas Muscarínicos/farmacologia , Oxotremorina/farmacologia , Pilocarpina/toxicidade , Piracetam/uso terapêutico , Receptores Muscarínicos/metabolismo , Convulsões/induzido quimicamente
14.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 169-176, Jan.-Feb. 2020. graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1088908

RESUMO

O fipronil é um inseticida de toxicidade seletiva amplamente empregado na agricultura e na medicina veterinária. Porém, há relatos de efeitos neurotóxicos dessa substância, que geram prejuízos para vertebrados. Avaliou-se a atividade locomotora, a coordenação motora e a atividade da enzima acetilcolinesterase cerebral em ratos expostos ao fipronil. Ratos Wistar machos adultos (n=15) receberam fipronil em dose de 30mg/kg, por via oral, durante 15 dias; o grupo controle (n=15) foi tratado com solução fisiológica, por via oral, no mesmo período. No 16° dia de experimentação, os animais foram submetidos aos testes de arena de campo aberto e hole board. No 17° dia, foram anestesiados e eutanasiados, procedendo-se à coleta de órgãos, e posteriormente foi feita a avaliação da AChE cerebral. A exposição ao fipronil não provocou alterações significativas sobre a coordenação motora e a atividade locomotora, porém gerou inibição significativa da atividade da acetilcolinesterase cerebral. Esses achados sugerem que o fipronil pode provocar efeitos neurotóxicos em curto prazo, os quais podem ser exacerbados caso a exposição seja prolongada.(AU)


Fipronil is a selective-toxicity insecticide widely used in agriculture and veterinary medicine. However, there are reports of neurotoxic effects of this substance, causing damages to vertebrates. We evaluated the locomotor activity, motor coordination and the activity of brain acetylcholinesterase in rats exposed to fipronil. Adult male Wistar rats (n= 15) received fipronil at a dose of 30mg/kg orally for 15 days; the Control group (n= 15) was treated with oral solution in the same period. On the 16th day of experimentation, the animals were submitted to the open field arena test and hole-board test. On the 17th day, they were anesthetized and euthanized, and organs were collected, and subsequently brain AChE was evaluated. Exposure to fipronil yielded no significant changes on motor coordination and locomotor activity but caused significant inhibition of brain acetylcholinesterase activity. These findings suggest that fipronil may cause short-term neurotoxic effects, which may be exacerbated if exposure is prolonged.(AU)


Assuntos
Animais , Ratos , Praguicidas/toxicidade , Acetilcolinesterase/análise , Exposição a Praguicidas , Síndromes Neurotóxicas/veterinária , Testes de Estado Mental e Demência , Ratos Wistar
15.
Res Microbiol ; 149(8): 585-94, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9795996

RESUMO

Bacteriocin production has been studied in very few anaerobic bacteria, and no report is available for Fusobacterium species. In the present study a total of 167 Fusobacterium isolates were tested for bacteriocin production: 70 isolates were obtained from the oral cavity of patients with periodontal disease, 47 were recovered from healthy oral sites of human subjects and 50 from the oral cavity of Callithrix penicillata. Autoantagonism and isoantagonism were observed when the bacteriocin-producing isolates were tested against themselves. Heteroantagonism was detected by testing the Fusobacterium isolates against 14 reference strains and 2 strains of Actinobacillus actinomycetemcomitans from our laboratory collection. The auto-, iso- and heteroantagonism phenomena observed in this comparative study suggest a possible ecological role for this (these) antagonistic substance(s) in the oral environment.


Assuntos
Antibiose , Bacteriocinas/biossíntese , Fusobacterium/metabolismo , Boca/microbiologia , Doenças Periodontais/microbiologia , Animais , Bactérias/crescimento & desenvolvimento , Callithrix , Fusobacterium/crescimento & desenvolvimento , Fusobacterium/isolamento & purificação , Humanos
16.
Onderstepoort J Vet Res ; 68(4): 275-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12026062

RESUMO

The prevalence of Leptospira interrogans serovars in dairy cattle was determined by analyzing 464 serum samples from cows on 15 properties in Garanhuns municipal district, Pernambuco State, Brazil. A microscopic seroagglutination test including 12 serovars of Leptospira interrogans as antigens was used. Samples with titres 100 were considered positive. Two hundred and twenty-one (47.63%) of the samples were positive to one or more serovars. The prevalence of the serovars was hardjo (21.98%), bratislava (15.73%), castellonis (11.64%), tarassovi (10.56%), pyrogenes (1.72%), icterohaemorrhagiae (1.08%), pomona (0.86%), wolffi (0.86%), grippotyphosa (0.86%), djasiman (0.43%), canicola (0.21 %), and copenhageni (0.21%).


Assuntos
Doenças dos Bovinos/epidemiologia , Leptospira interrogans , Leptospirose/veterinária , Testes de Aglutinação/veterinária , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/microbiologia , Feminino , Leptospira interrogans/classificação , Leptospira interrogans/imunologia , Leptospirose/epidemiologia , Estudos Soroepidemiológicos , Sorotipagem/veterinária
17.
Cad Saude Publica ; 11(3): 439-47, 1995.
Artigo em Português | MEDLINE | ID: mdl-12973623

RESUMO

The authors studied a sample of students entering the first grade in the Osasco public school system in order to determine both the prevalence of anemia and nutritional status. Osasco is part of the Greater S o Paulo Metropolitan Area. Diagnosis of anemia was made through the hemoglobin concentration of blood from digital puncture. World Health Organization (WHO) levels were used to define anemia. Nutritional Status assessment. was made through weight/age and height/age indices, using Z score distribution and the National Center for Health Statistics (NCHS) reference levels. Prevalence of anemia was 51%. Prevalence levels varied according to the schools' geographic location: 56.9% in peripheral neighborhoods and 41.7% in central areas. Children with illiterate parents had a higher prevalence of this condition. Risk of anemia was higher for children who were over eight years of age when entering the first grade. Acute malnutrition was not found. Prevalence was higher than expected and points to the urgent need to establish an anemia control program for schoolchildren in this population.

18.
Arq. bras. med. vet. zootec. (Online) ; 71(1): 86-92, jan.-fev. 2019. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-989387

RESUMO

A imuno-histoquímica (IHQ) é considerada uma ferramenta rápida e precisa para a identificação de protozoários, como Toxoplasma gondii, em tecidos fetais e placentários. Neste estudo foi avaliada a imunodetecção de Toxoplasma gondii em tecido placentário de cabras naturalmente infectadas. Foram coletadas e analisadas 80 amostras de placentas de cabras procedentes de único rebanho com sorologia positiva para T. gondii na técnica de ELISA. Na histopatologia, 27/80 amostras apresentaram lesões sugestivas de infecção por protozoários. Após a avaliação histopatológica, procedeu-se à realização da técnica de imuno-histoquímica, obtendo-se 85,2% (23/27) de amostras com marcação positiva. A imunodetecção ocorreu no epitélio de revestimento das vilosidades coriônicas e foi classificada de acordo com o grau de intensidade da imunomarcação. Também foi evidenciada imunomarcação no interior dos vasos sanguíneos fetais em 8,69% (2/23) das amostras. Este estudo demonstrou que a técnica de IHQ se comportou como uma ferramenta valiosa no diagnóstico da infeção por T. gondii em tecido placentário de cabras naturalmente infectadas e complementou, de forma decisiva, o diagnóstico, além de agregar maior valor aos resultados obtidos nas análises histopatológica e sorológica.(AU)


Immunohistochemistry (IHC) is considered to be a rapid and accurate tool for the identification of protozoa such as Toxoplasma gondii in fetal and placental tissues. In this study, we evaluated the immunodetection of Toxoplasma gondii in placental tissue from naturally infected goats. A total of 80 samples of goat placentas from a single herd with positive ELISA serology for T. gondii were collected and analyzed. In the histopathology, 27/80 samples presented lesions suggestive of protozoal infection. After the histopathological evaluation, the immunohistochemistry technique was performed, obtaining 85.2% (23/27) of samples with positive marking. Immunodetection occurred in the lining epithelium of the chorionic villi and was classified according to the degree of intensity of the immunostaining. Immunostaining within the fetal blood vessels was also evidenced in 8.69% (2/23) of the samples. This study demonstrated that the IHQ technique behaved as a valuable tool in the diagnosis of T. gondii infection in placental tissue of naturally infected goats completing the diagnosis in a decisive way and adding greater value to the results obtained in the histopathological and serological analysis.(AU)


Assuntos
Animais , Placenta/microbiologia , Toxoplasma/imunologia , Ruminantes/microbiologia
19.
Open Biomed Eng J ; 8: 20-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24772196

RESUMO

Hybrid foam (BG-PVA) with 50 % Bioactive glass (BG) and 50 % polyvinyl alcohol (PVA) was prepared by sol-gel process to produce scaffolds for bone tissue engineering. The pore structure of hydrated foams was evaluated by 3-D confocal microscopy, confirming 70% porosity and interconnected macroporous network. In this study, we assessed the putative advantage of coating with osteostatin pentapeptide into BG-PVA hybrid scaffolds to improve their bioactivity. In vitro cell culture experiments were performed using mouse pre-osteoblastic MC3T3-E1 cell line. The exposure to osteostatin loaded-BG-PVA scaffolds increase cell proliferation in contrast with the unloaded scaffolds. An in vivo study was selected to implant BG-PVA scaffolds, non-coated (Group A) or coated (Group B) with osteostatin into non critical bone defect at rabbit femur. Both groups showed new compact bone formation on implant surface, with lamellae disposed around a haversian canal forming osteons-like structure. We observed signs of inflammation around the implanted unloaded scaffold at one month, but resolved at 3 months. This early inflammation did not occur in Group B; supporting the notion that osteostatin may act as anti-inflammatory inhibitor. On the other hand, Group B showed increased bone formation, as depicted by many new trabeculae partly mineralized in the implant regenerating area, incipient at 1 month and more evident at 3 months after implantation. PVA/BG hybrid scaffolds present a porous structure suitable to support osteoblast proliferation and differentiation. Our in vitro and in vivo findings indicate that osteostatin coating improves the osteogenic features of these scaffolds.

20.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 321-326, Jan.-Feb. 2018. graf, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1038584

RESUMO

The objective of this study was to describe lesions in four birds, victims of collisions with aircraft, coming from the International Airport of Recife/Guararapes Gilberto Freyre, Pernambuco, Brazil. Contused wounds were predominant in birds in this study, characterized by the presence of fractures, bruises and hematomas and justified by the blunt action promoted by the type of vulnerant agent involved (aircraft). The analysis under medico-legal veterinary aspect of lesions in bird strike is essential, because in addition to the attempt to establish a standard for differentiating the aircraft lesions, it can guide the bird strike hazard management programs at airports, since the necropsy allows the identification of the species involved or at least facilitates the obtaining biological material for identification.(AU)


Assuntos
Animais , Choque Traumático/veterinária , Ferimentos e Lesões/veterinária , Aves , Animais Selvagens , Médicos Veterinários , Médicos Legistas , Aeroportos
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