Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 96
Filtrar
1.
Braz J Biol ; 83: e275645, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126636

RESUMO

The objective of this study was to verify the flight radius and the influence of the climatic season and period of the day on the external activity of Melipona rufiventris bees. The forager bees were released at different distances to evaluate the flight radius. The following were considered for external activities in the four different seasons of the year (Winter, Autumn, Spring, Summer): the entry with no apparent load was considered as nectar/water, entry with defined and opaque mass in the corbicula was considered as pollen, the entry with undefined and shiny mass in the corbicula was considered as resin/clay or bee exit no load and removal of debris, mass trapped by the jaws. Assessments were performed between 6 am and 6 pm each month. M. rufiventris can reach distances of 2 500 meters, however the return decreases as the distance increases. The species performs all activities in and out of the colony during all seasons of the year and periods between 6 am and 6 pm but reduce nectar/water collection and exit from the box without apparent load and with debris between 6:00 am and 10 am in winter. It is concluded that distances greater than 1 500 meters hinder the external activity of bees which is influenced by air temperature, air humidity, time of day, season of the year and food availability.


Assuntos
Néctar de Plantas , Rádio (Anatomia) , Abelhas , Animais , Estações do Ano , Umidade , Água
2.
Cereb Circ Cogn Behav ; 3: 100143, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324413

RESUMO

Patients with carotid occlusive disease express altered hemodynamics in the post-occlusive vasculature and lesions commonly attributed to cerebral small vessel disease (SVD). We addressed the question if cerebral perforating artery flow measures, using a novel 7T MRI technique, are altered and related to SVD lesion burden in patients with carotid occlusive disease. 21 patients were included with a uni- (18) or bilateral (3) carotid occlusion (64±7 years) and 19 controls (65±10 years). Mean flow velocity and pulsatility in the perforating arteries in the semi-oval center (CSO) and basal ganglia (BG), measured with a 2D phase contrast 7T MRI sequence, were compared between patients and controls, and between hemispheres in patients with unilateral carotid occlusive disease. In patients, relations were assessed between perforating artery flow measures and SVD burden score and white matter hyperintensity (WMH) volume. CSO perforating artery flow velocity was lower in patients than controls, albeit non-significant (mean difference [95% confidence interval] 0.08 cm/s [0.00-0.16]; p = 0.053), but pulsatility was similar (0.07  [-0.04-0.18]; p = 0.23). BG flow velocity and pulsatility did not differ between patients and controls (velocity = 0.28 cm/s [-0.32-0.88]; p = 0.34; pulsatility = 0.00 [-0.10-0.11]; p = 0.97). Patients with unilateral carotid occlusive disease showed no significant interhemispheric flow differences. Though non-significant, within patients lower CSO (p = 0.06) and BG (p = 0.11) flow velocity related to larger WMH volume. Our findings suggest that carotid occlusive disease may be associated with abnormal cerebral perforating artery flow and that this relates to SVD lesion burden in these patients, although our observations need corroboration in larger study populations.

3.
J Comp Pathol ; 173: 49-57, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31812173

RESUMO

Malignant melanomas (MMs) represent 7% of all malignant neoplasms in dogs. Oral melanocytic neoplasms are often malignant and associated with poor prognosis. There are no universally accepted prognostic markers for canine oral melanoma. Galectin (Gal)-3 is a prognostic marker for human neoplasms such as thyroid, gastric, colorectal and prostate cancers. The protein is related to processes that favour cancer progression, such as angiogenesis, proliferation and apoptosis. The aim of the present study was to characterize the immunohistochemical expression of Gal-3 in canine oral melanomas and to compare it with post-surgical survival, the expression of apoptosis-related proteins and other known prognostic tools. Twenty-seven samples of canine oral melanomas were evaluated for Gal-3, B-cell lymphoma (BCL) 2, caspase (CASP) 3 and Ki67 expression, mitotic index and degree of nuclear atypia. Gal-3 cytoplasmic positivity was correlated positively, while nuclear positivity was correlated negatively, with survival. The intensity of BCL2 labelling was also correlated positively with Gal-3 cytoplasmic positivity. Higher nuclear atypia was observed in dogs with melanoma that died due to the tumour, as well as in dogs that survived for <1 year after surgery. We have confirmed the importance of nuclear atypia for MMs and suggest that Gal-3 is a valuable prognostic indicator for this neoplasm. More in-depth studies are needed to unveil Gal-3 functions in canine MMs using larger sample sizes.


Assuntos
Biomarcadores Tumorais/metabolismo , Doenças do Cão , Galectina 3/metabolismo , Melanoma/veterinária , Neoplasias Bucais/veterinária , Animais , Biomarcadores Tumorais/análise , Doenças do Cão/metabolismo , Doenças do Cão/patologia , Cães , Galectina 3/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-31374295

RESUMO

In the present study we describe the molecular characterization of the two paralogous mitochondrial peroxiredoxins from Trematomus bernacchii, a teleost that plays a pivotal role in the Antarctic food chain. The two putative amino acid sequences were compared with orthologs from other fish, highlighting a high percentage of identity and similarity with the respective variant, in particular for the residues that are essential for the characteristic peroxidase activity of these enzymes. The temporal expression of Prdx3 and Prdx5 mRNAs in response to short-term thermal stress showed a general upregulation of prdx3, suggesting that this isoform is the most affected by temperature increase. These data, together with the peculiar differences between the molecular structures of the two mitochondrial Prdxs in T. bernacchii as well as in the tropical species Stegastes partitus, suggest an adaptation that allowed these poikilothermic aquatic vertebrates to colonize very different environments, characterized by different temperature ranges.


Assuntos
Mitocôndrias/enzimologia , Perciformes/metabolismo , Peroxirredoxinas , Sequência de Aminoácidos , Animais , Regiões Antárticas , Proteínas de Peixes/classificação , Proteínas de Peixes/metabolismo , Expressão Gênica , Aquecimento Global , Peroxirredoxinas/classificação , Peroxirredoxinas/metabolismo , Filogenia , Isoformas de Proteínas , Temperatura
5.
Artigo em Inglês | MEDLINE | ID: mdl-29253620

RESUMO

In the present study, we describe the identified and characterized the gene and the transcript of a novel glutathione peroxidase-7 (GPx7) from the solitary ascidian Ciona robusta, an invertebrate chordate widely distributed in temperate shallow seawater. The putative nucleotide and amino acid sequences were compared with those of GPx7 from other metazoans and phylogenetic analysis suggests the presence of a high evolutionary pressure in the contest of neutral evolution. The mRNA of CrGPx7 is located in hemocytes and ovarian follicular cells, as revealed by in situ hybridization. The time course of CrGPx7 mRNA levels in the presence of Cd, Cu and Zn, showed upregulation in the final stages of the experiments, suggesting a role of GPx7 in late protection from oxidative stress. Our in silico analyses of the crgpx7 promoter region revealed putative consensus sequences similar to mammalian metal-responsive elements (MRE) and xenobiotic-responsive elements (XRE), suggesting that the transcription of these genes directly depends on metals. Cell-free extract from C. robusta tissues show the presence of selenium-independent GPx activity that is inhibited by the presence of metals.


Assuntos
Cádmio/toxicidade , Cobre/toxicidade , Glutationa Peroxidase/metabolismo , Modelos Moleculares , Urocordados/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Animais , Organismos Aquáticos/efeitos dos fármacos , Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/metabolismo , Biologia Computacional , Indução Enzimática/efeitos dos fármacos , Sistemas Inteligentes , Feminino , Glutationa Peroxidase/química , Glutationa Peroxidase/genética , Hemócitos/citologia , Hemócitos/efeitos dos fármacos , Hemócitos/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Itália , Masculino , Mar Mediterrâneo , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/metabolismo , Distribuição Aleatória , Elementos de Resposta/efeitos dos fármacos , Urocordados/crescimento & desenvolvimento , Urocordados/metabolismo
6.
J Comp Physiol B ; 186(1): 59-71, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26433650

RESUMO

In the present study, we describe the purification and molecular characterization of two peroxiredoxins (Prdxs), referred to as Prdx6A and Prdx6B, from Trematomus bernacchii, a teleost widely distributed in many areas of Antarctica, that plays a pivotal role in the Antarctic food chain. The two putative amino acid sequences were compared with Prdx6 orthologs from other fish, highlighting a high percentage of identity and similarity with the respective variant, in particular for the residues that are essential for the characteristic peroxidase and phospholipase activities of these enzymes. Phylogenetic analyses suggest the appearance of the two prdx6 genes through a duplication event before the speciation that led to the differentiation of fish families and that the evolution of the two gene variants seems to proceed together with the evolution of fish orders and families. The temporal expression of Prdx6 mRNA in response to short-term thermal stress showed a general upregulation of prdx6b and inhibition of prdx6a, suggesting that the latter is the variant most affected by temperature increase. The variations of mRNA accumulation are more conspicuous in heart than the liver, probably related to behavioral changes of the specimens in response to elevated temperature. These data, together with the peculiar differences between the molecular structures of the two Prdx6s in T. bernacchii as well as in the tropical species Stegastes partitus, suggest an adaptation that allowed these poikilothermic aquatic vertebrates to colonize very different environments, characterized by different temperature ranges.


Assuntos
Peixes/metabolismo , Peroxirredoxina VI/química , Temperatura , Sequência de Aminoácidos , Animais , Regiões Antárticas , Clonagem Molecular , Regulação da Expressão Gênica/fisiologia , Fígado/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Miocárdio/metabolismo , Peroxirredoxina VI/genética , Peroxirredoxina VI/metabolismo , Filogenia , Conformação Proteica
7.
Aquat Toxicol ; 114-115: 14-22, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22417760

RESUMO

Exposure to metals is known to generate oxidative stress risk in living organisms, which are able to respond with the induction of antioxidant defenses, both enzymatic and non-enzymatic. Glutathione (GSH) is considered to be an important cellular component involved in protecting cells, both as metal chelating agent and oxygen radical scavenger. In this work we used molecular techniques to analyze the nucleotide and predicted amino acid sequences of genes involved in GSH biosynthesis, γ-glutamyl-cysteine ligase catalytic subunit (ci-gclc), γ-glutamyl-cysteine ligase modifier subunit (ci-gclm) and GSH synthase (ci-gs) in the solitary tunicate Ciona intestinalis. We also studied the transcription of the above genes after in vivo exposure to Cd, Cu and Zn by semiquantitativ RT-PCR to improve our knowledge about the relationship between metal-induced oxidative stress and GSH production and locate mRNA expression by in situ hybridization (ISH). These genes exhibit a good level of sequence conservation with metazoan homologs generally, especially for residues important for the activity of the enzymes. Phylogenetic analyses indicate that the three enzymes evolved in different ways, Ci-GCLC and Ci-GS being mostly correlated with invertebrate proteins, Ci-GCLM being as sister group of vertebrate GCLMs. Our in silico analyses of the ci-gs and ci-gclc promoter regions revealed putative consensus sequences similar to mammalian metal-responsive elements (MRE) and antioxidant response elements (ARE), indicating that the transcription of these genes may directly depend on metals and/or reactive oxygen species. Results highlight a statistically significant increase in gene transcription, demonstrating that metal treatments have inducible effects on these genes. They can modulate gene transcription not only through MREs but also through AREs, as a consequence of metal-dependent ROS formation. The ISH location of Ci-GS and Ci-GCLC mRNAs shows that the cells most involved in glutathione biosynthesis are circulating hemocytes. The data presented here emphasize the importance of complex metal regulation of ci-gclc, ci-gclm and ci-gs transcription, which can create an efficient detoxification pathway allowing C. intestinalis to survive in continued elevated presence of metals in the environment.


Assuntos
Ciona intestinalis/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/biossíntese , Metais/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , Estresse Oxidativo
8.
Acta Biomater ; 4(4): 1089-94, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18308650

RESUMO

The aim of this work was to study the phase transformation during the setting reaction of two calcium phosphate bone cements based on either alpha tricalcium phosphate (alpha-TCP) or tetracalcium phosphate (TetCP) initial solid phase, and a magnesium carbonate-phosphoric acid solution as the hardening liquid. Low molecular weight (38.2 kDa) chitosan was used to retard the cement's setting reaction. To follow the kinetics of the phase development, an energy dispersive X-ray diffraction technique was applied. This technique allowed the collection of diffraction patterns from the cement pastes in situ starting from 1 min of the setting process. In the case of the TetCP-based cement, the appearance and evolution of an intermediate phase was detected.


Assuntos
Cimentos Ósseos/química , Fosfatos de Cálcio/química , Quitosana/química , Difração de Raios X , Microscopia Eletrônica de Varredura , Fatores de Tempo
9.
Intern Emerg Med ; 2(1): 24-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17551680

RESUMO

INTRODUCTION: Oral anticoagulants (OAs) are significantly more effective than Aspirin in the prevention of cerebrovascular accidents among patients with atrial fibrillation (AF). Several studies, however, showed OAs to be widely underused in these patients. OBJECTIVE: To assess the appropriateness of antithrombotic therapy in an Italian population of AF patients. METHODS: Two hundred and fifty-five consecutive patients affected by nonvalvular AF participated in the study. Data were collected on demographic characteristics, risk factors for stroke, current prophylactic therapy, and perceived or actual risk factors for bleeding. INR levels were measured. Patients were stratified by their risk for stroke (214 at high risk, 21 moderate, 20 low), and their prophylactic therapy was analysed in light of international antithrombotic therapy recommendations. After therapy adjustment, 203 of our patients were followed-up for the occurrence of cerebrovascular events for an average of 27 months. RESULTS: Upon admission, 35% (n=75) of patients in the high-risk category were either taking no antithrombotic prophylaxis or were being treated with Aspirin. In addition, 38 of 139 patients receiving OAs had an INR<2. Thus, a total of 113 (52.8%) high-risk subjects were not receiving adequate antithrombotic therapy. Of high-risk patients not treated with OAs, 46.7% reported no perceived or actual risk factors for bleeding. The annual incidence of cerebrovascular accidents was 3.8% among 163 high-risk patients assigned to OA treatment, and 4.5% among 39 patients given Aspirin treatment. Relative to expected annual incidence rates, cerebrovascular risk in anticoagulated patients was reduced by about 70%. CONCLUSIONS: Underuse of OAs is still common in Italy, and much of it cannot be explained by the concern for haemorrhage. Support and training in the complex task of anticoagulation management may help to extend this efficacious prophylactic therapy to all patients who may benefit from it.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Idoso , Prescrições de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Itália , Masculino
10.
Eur J Cancer Care (Engl) ; 16(3): 258-62, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17508946

RESUMO

Among a large series of cancer patients treated with a combination of chemotherapy and sessions of hyperthermia, particular attention was given to a specific group of patients with advanced cancer who refused standard, aggressive, treatment. In these cases, hyperthermia was associated to low-dose (metronomic) chemotherapy. No toxicity was reported in any of our patients, while a marginal benefit in terms of tumour progression was observed. During therapy, we could detect a coagulative perturbation that deserves careful discussion. In our opinion, this experience should be matter of debate to conclude if current response criteria (WHO/UICC and RECIST) in treating cancer patients are really suitable tools to evaluate new, and non-aggressive anticancer strategies.


Assuntos
Indutores da Angiogênese/uso terapêutico , Antineoplásicos/uso terapêutico , Hipertermia Induzida/métodos , Neoplasias/tratamento farmacológico , Cuidados Paliativos/métodos , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Cuidados Paliativos/ética , Recusa do Paciente ao Tratamento
11.
J Mater Sci Mater Med ; 17(7): 597-604, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16770543

RESUMO

Synthetic carbonated apatite ceramics are considered as promising alternative to auto- and allograft materials for bone substitute. The aim of this study was to investigate the thermal stability of an AB-type carbonated apatite in the wide temperature range. The data on the thermal stability have to allow the conditions of the sintering of the ceramics to be controlled. Initial carbonated apatite powders were prepared by interaction between calcium oxide and ammonium hydrogen phosphate with addition of ammonium carbonate. Decomposition process was monitored by infra red spectroscopy, weight loss and X-ray diffraction of solid, and by infra red analysis of condensed gas phase resulted from the thermal decomposition of the sample in equilibrium conditions. Features of carbon monoxide and carbon dioxide release were revealed. The synthesized AB-type carbonated apatite is started to decompose at about 400 degrees Celsius releasing mainly carbon dioxide, but retained some carbonate groups and apatite structure at the temperature 1100 degrees Celsius useful to prepare porous carbonate-apatite ceramics intended for bone tissue engineering scaffolds.


Assuntos
Apatitas/análise , Materiais Biocompatíveis/química , Substitutos Ósseos , Carbonatos/análise , Durapatita/química , Compostos de Cálcio/química , Carbonatos/química , Óxidos/química , Fosfatos/química , Pós/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
12.
Diabetologia ; 49(6): 1169-74, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16570157

RESUMO

AIMS/HYPOTHESIS: The metabolic syndrome is associated with proinflammatory and prothrombotic states. This study was designed to assess the behaviour of soluble CD40 ligand (sCD40L) and prothrombin fragment F (1+2), a marker of thrombin generation, in patients with the metabolic syndrome. METHODS: We investigated 106 patients with the metabolic syndrome, diagnosed according to the ATPIII report, and 104 subjects without the metabolic syndrome. RESULTS: Plasma values of sCD40L and F (1+2) were higher in patients with the metabolic syndrome (4.11+/-1.64 vs 2.61+/-0.89 ng/ml and 1.54+/-0.49 vs 0.87+/-0.21 nmol/l, respectively; p < 0.001) and were significantly correlated (r = 0.925, p < 0.001). Stepwise multiple linear regression analysis showed that sCD40L was significantly associated with F (1+2), female sex and waist circumference. CONCLUSIONS/INTERPRETATION: Patients with the metabolic syndrome have enhanced values of plasma sCD40L and F (1+2). The study provides further insight into the relationship between metabolic syndrome, inflammation and thrombosis.


Assuntos
Ligante de CD40/sangue , Síndrome Metabólica/sangue , Trombina/fisiologia , Adulto , Idoso , Antígenos CD/sangue , Tamanho Corporal , Feminino , Humanos , Inflamação , Masculino , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/fisiopatologia , Fragmentos de Peptídeos/metabolismo , Protrombina/metabolismo
13.
Arq. ciênc. vet. zool. UNIPAR ; 7(2): 123-128, jul.-dez. 2004. tab
Artigo em Português | LILACS | ID: lil-418086

RESUMO

A cavidade oral a faringe ocupam o quarto lugar em incidência de neoplasias malignas no corpo do cão doméstico. As neoplasias orais malignas mais comuns são melanoma, o carcinoma de células escamosas e o fibrossarcoma. A epúlide e a papilomatose oral respondem pela grande maioria das neoplasias orais benignas em carnívoros domésticos. Em geral, a literatura relata que os machos são mais freqüentemente acometidos que as fêmeas. A maioria dos casos atinge animais de idade média a avançada, ainda que não sejam raros os acometimentos em animais jovens. Raças como o Cocker Spaniel, o Pastor Alemão e o Boxer são amplamente citadas como as mais predispostas a formações neoplásicas. Neste trabalho, foram estudados os casos de neoplasia oral, comprovados por exame histopatológico, que foram atendidos no Centro Odontológico Veterinário – Odontovet® - SP – entre os anos de 1994 e 2003. De todos os atendimentos de cães, 5,2% foram destinados ao tratamento de formações neoplásicas orais. Noventa e uma formações (45,5%) eram neoplasias de caráter benigno e 100 (50%) eram malignas. Os outros 4,5% dos casos correspondem a tumores diversos e de ocorrência rara na cavidade oral de cães. O melanoma maligno foi o tumor mais freqüente (53% dos casos) seguido pelo carcinoma espino-celular (21%) e pelo fibrossarcoma (11%). A epúlide respondeu pela grande maioria das formações benignas (50%). A idade média dos cães acometidos por lesões malignas foi de 7,3 anos e de 8,5 para aqueles acometidos por lesões benignas. Os animais mais acometidos foram os sem raça definida (SRD) (30 casos), Poodle (27 casos), Cocker Spaniel (18), Pastor Alemão (16), Boxer (15) e Dobermann Pinscher (12). No Brasil, Poodles, Cocker Spaniels, Pastores Alemães, Boxers e os SRDs estão entre os que mais freqüentemente são conduzidos ao atendimento odontológico para avaliação de tumefações em cavidade oral.


The oral cavity and the pharynx are responsible for the fourth most attacked site by malignant neoplasias. The most common malignant oral tumors in dogs are the melanoma, the squamous cell carcinoma (SCC) and the fi brossarcoma. The epulis and the oral papiloma are the most frequent benign tumors in the domestic carnivorous. Papers report that neoplasia occur in male dogs more than in females. The majority of it occur in middle or advanced age, although it is not rare to occur in young dogs. The Cocker Spaniel, German Shepherd Dog and the Boxer are the most frequently attacked by tumors. This work compiled the oral neoplasia diagnosed by histopathologic exam by the Centro Odontológico Veterinário ­ Odontovet®-SP ­ from 1994 to 2003. Of all dogs, 5.2% were submmitted to treatment of oral neoformation. Ninety one (45,5%) were benign tumors and a hundred (50%) were malignant. The other 4,5% were mixed and rare oral tumors. The malignant melanoma was the most commonly observed (53%) followed by SCC (21%) and by fi brossarcoma (11%). The epúlide was the most frequent of the benign tumors (50%). The mean age of the dogs with malignant neoformations was around 7.3 years old and with benign, around 8.5 years old. Mixed breed was the most involved (30 cases), followed by Poodle (27), Cocker Spaniel (18), German Shepherd Dog (16), Boxer (15) and Dobermann Pinscher (12). In Brazil, Poodles, Cocker Spaniels, German Shepard, Boxers and the mixed breeds are frequently refered to dental exams or to oral tumor treatment.


La cavidad oral y la faringe de los perros corresponden al cuarto local más acometido por los tumores malignos. Las neoplasías orales malignas más comunes en perros son el melanoma, el carcinoma de células escamosas y el fi brosarcoma. El epúlide y la papilomatosis responden por gran parte de los acometimientos benignos de los carnívoros domésticos. En general, la literatura relata las hembras como siendo menos afectadas que los machos. Gran parte de los casos alcanzan animales con edad media o avanzada, pero no son raros los acometimientos en los animales jóvenes. Razas como el Cocker Spaniel, el Pastor Alemán y el Boxer son ampliamente citadas como las más predispuestas a neoformaciones neoplásicas. En este estudio, fueron acompañados los casos de neoplasía oral comprobados por examen histopatológico que fueron atendidos en el Centro Odontológico Veterinario ­ Odontovet® - entre los años de 1994 y 2003. De todos los perros atendidos, 5,2% fueron destinados al tratamiento de formaciones neoplásicas orales. Noventa y una formaciones (el 45,5%) fueron neoplasías de caracter benigno y 100 (el 50%) fueron malignas. Los otros 4,5% de los casos correspondieron a tumores diversos y raros de ser encontrados en la cavidad oral de perros. El melanoma maligno fue el tumor más frecuente (el 53% de los casos), seguido por el carcinoma espino-celular (el 21%) y fi brosarcoma (el 11%). El epúlide respondió por la grand mayoría de las formaciones benignas (el 50%). La edad media de los perros acometidos por lesiones malignas fue de 7,3 años y por lesiones benignas, 8,5 años. Los animales más acometidos fueron los mestizos (30 casos), Poodle (27 casos), Cocker Spaniel (18), Pastor Alemán (16), Boxer (15) y Dobermann Pinscher (12). En Brasil, Poodles, Cocker Spaniels, Pastores Alemanes, Boxers y mestizos están entre los animales que más frecuentemente son conducidos a los atendimientos odontológicos para evaluación de las neoformaciones en la cavidad oral.


Assuntos
Carcinoma de Células Escamosas , Fibrossarcoma/veterinária , Melanoma , Neoplasias Bucais/epidemiologia , Odontologia/veterinária
14.
J Biomed Mater Res B Appl Biomater ; 71(2): 441-7, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15389504

RESUMO

The mineral constituent of bone tissue is a carbonate-substituted apatite (CHA). The thermal stability of the CHA has been revealed to depend on the substitution type and degree, although relatively little is known about this behavior. The aim of this study was to investigate the carbonate loss from synthetic CHAs in equilibrium conditions in a wide temperature range. An approach based on FTIR spectroscopy of condensed gas phase was applied to evaluate the CO and CO2 release with increasing temperature. Four different CHAs were studied, which were prepared by either precipitation from solution or the solid-state interaction. The samples differ from each other by the substitution degree. In one of the samples calcium was partially substituted by magnesium. Decomposition was shown to start at surprisingly low temperature, about 400 degrees C, and the CO content increases monotonously with the increase of temperature. The CO2 content goes through a maximum due to its decomposition into carbon monoxide and oxygen, the temperature of this maximum being strongly dependent on the chemical synthesis route. Therefore, control of the sintering atmosphere with respect to the CO2/CO ratio is needed when preparing the carbonated apatite bioceramics.


Assuntos
Apatitas/análise , Carbonatos/análise , Carbono/análise , Magnésio , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
15.
Aliment Pharmacol Ther ; 20(3): 289-94, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15274665

RESUMO

BACKGROUND: Conflicting data have been reported concerning the relationship between Helicobacter pylori infection and coronary heart disease. AIM: To evaluate clotting system activation and plasma levels of tumour necrosis factor-alpha, a procoagulant cytokine, in patients with H. pylori-positive and -negative gastritis. METHODS: Three groups of patients were identified: 38 with H. pylori-positive gastritis, 18 with H. pylori-negative gastritis, and 40 H. pylori-negative controls with normal gastric mucosa. Plasma levels of prothrombin fragment 1 + 2 (F1 + 2) and tumour necrosis factor-alpha were assayed. Patients were also controlled after 2 and 6 months following standard H. pylori eradication treatment. RESULTS: At baseline, fragment 1 + 2 and tumour necrosis factor-alpha levels in H. pylori-positive patients were significantly higher than those in H. pylori-negative patients with gastritis (P < 0.05 and P < 0.01, respectively). After H. pylori eradication, fragment 1 + 2 and tumour necrosis factor-alpha levels showed a significant decrease at 2 months (P = 0.03 and P = 0.02, respectively) and a further reduction at 6 months, reaching levels observed in H. pylori-negative patients and controls. CONCLUSIONS: The increase thrombin generation rate and the correlation of plasma fragment 1 + 2 and tumour necrosis factor-alpha levels in H. pylori-positive patients suggest a role for inflammation in mediating the relationship between H. pylori infection and activation of the clotting system.


Assuntos
Coagulação Sanguínea/fisiologia , Infecções por Helicobacter/metabolismo , Helicobacter pylori , Trombina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Idoso , Antibacterianos , Quimioterapia Combinada/uso terapêutico , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Gastrite/sangue , Infecções por Helicobacter/sangue , Infecções por Helicobacter/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade
16.
Circulation ; 110(10): 1326-9, 2004 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-15249506

RESUMO

BACKGROUND: CD40 ligand (CD40L) expression on platelets is mediated by agonists, but the underlying mechanism is still unclear. METHODS AND RESULTS: CD40L expression was measured in platelets from healthy subjects both with and without the addition of antioxidants or a phospholipase A2 (PLA2) inhibitor and in platelets from 2 patients with an inherited deficiency of gp91phox. Immunoprecipitation analysis was also performed to determine whether normal platelets showed gp91phox expression. Unlike catalase and mannitol, superoxide dismutase inhibited agonist-induced platelet CD40L expression in healthy subjects. Immunoprecipitation analysis also showed that platelets from healthy subjects expressed gp91phox. In 2 male patients with inherited gp91phox deficiency, collagen-, thrombin-, and arachidonic acid-stimulated platelets showed an almost complete absence of superoxide anion (O(2)(-)) and CD40L expression. Incubation of platelets from healthy subjects with a PLA2 inhibitor almost completely prevented agonist-induced O(2)(-) and CD40L expression. CONCLUSIONS: These data provide the first evidence that platelet CD40L expression occurs via arachidonic acid-mediated gp91phox activation.


Assuntos
Ácido Araquidônico/metabolismo , Plaquetas/metabolismo , Ligante de CD40/biossíntese , Glicoproteínas de Membrana/fisiologia , NADPH Oxidases/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Adulto , Antioxidantes/farmacologia , Ácidos Araquidônicos/farmacologia , Aspirina/farmacologia , Plaquetas/efeitos dos fármacos , Ligante de CD40/sangue , Ligante de CD40/genética , Catalase/farmacologia , Colágeno/farmacologia , Doença Granulomatosa Crônica/sangue , Doença Granulomatosa Crônica/enzimologia , Humanos , Masculino , Manitol/farmacologia , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , NADPH Oxidase 2 , NADPH Oxidases/deficiência , NADPH Oxidases/genética , Fosfolipases A/antagonistas & inibidores , Fosfolipases A2 , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Superóxido Dismutase/farmacologia , Superóxidos/metabolismo , Trombina/farmacologia
17.
J Thromb Haemost ; 1(3): 523-31, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12871461

RESUMO

In a first study, we performed a cross-sectional analysis of urinary excretion of isoprostanes, IPF(2alpha-III) and (VI), and monocyte tissue factor (TF) antigen and activity between 11 antiphospholipid (APL) antibody-positive patients and 13 APL negative subjects. In a second study, 11 APL positive patients were randomly supplemented either with (n = 6) or without (n = 5) antioxidants (vitamin E at 900 IU day(-1), vitamin C at 2000 mg day(-1)) for 6 weeks. In a third study, TF and superoxide anion were measured in human monocytes incubated with anti-beta(2) glycoprotein 1 (beta(2)GP(1)) or control IgG, either with or without vitamin E. APL-positive patients had higher values of isoprostanes (P < 0.05) and monocyte TF antigen (P = 0.001) and activity (P = 0.0001) than APL-negative subjects. Only in APL positive patients did monocyte TF antigen correlate significantly with IPF(2alpha-III) (rho 0.79; P < 0.003) and IPF(2alpha-VI) (rho = 0.87; P < 0.0001). In patients who received antioxidant supplementation, we found a significant decrease of isoprostanes (P < 0.05) and monocyte TF antigen (P < 0.01) and activity (P < 0.007). In vitro experiments demonstrated that anti-beta(2)GP(1) antibodies dose-dependently enhanced the monocyte production of the superoxide anion and TF, which were significantly inhibited by vitamin E. This study demonstrates that in APL-positive patients, oxidative stress contributes to activate the clotting system via over-expression of monocyte TF. We suggest that anti-beta(2)GP(1) antibodies could play a pivotal role by enhancing the monocyte production of oxygen free radicals.


Assuntos
Anticorpos Antifosfolipídeos , Antioxidantes/farmacologia , Monócitos/metabolismo , Estresse Oxidativo/fisiologia , Tromboplastina/biossíntese , Adulto , Síndrome Antifosfolipídica/metabolismo , Estudos Transversais , Relação Dose-Resposta a Droga , Feminino , Humanos , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Pessoa de Meia-Idade , Superóxidos
18.
Braz. j. vet. res. anim. sci ; 40: 208-209, 2003.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1470630

RESUMO

O artigo não apresenta resumo.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...