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1.
Alcohol ; 40(1): 3-17, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17157716

RESUMO

Chronic ethanol (EtOH) drinking produces neuronal alterations within the limbic system. To investigate changes in protein expression levels associated with EtOH drinking, inbred alcohol-preferring (iP) rats were given one of three EtOH access conditions in their home-cages: continuous ethanol (CE: 24h/day, 7days/week access to EtOH), multiple scheduled access (MSA: four 1-h sessions during the dark cycle/day, 5 days/week) to EtOH, or remained EtOH-naïve. Both MSA and CE groups consumed between 6 and 6.5g of EtOH/kg/day after the 3rd week of access. On the first day of EtOH access for the seventh week, access was terminated at the end of the fourth MSA session for MSA rats and the corresponding time point (2300h) for CE rats. Ten h later, the rats were decapitated, brains extracted, the nucleus accumbens (NAcc) and amygdala (AMYG) microdissected, and protein isolated for 2-dimensional gel electrophoretic analyses. In the NAcc, MSA altered expression levels for 12 of the 14 identified proteins, compared with controls, with six of these proteins altered by CE access, as well. In the AMYG, CE access changed expression levels for 22 of the 27 identified proteins, compared with controls, with 8 of these proteins altered by MSA, as well. The proteins could be grouped into functional categories of chaperones, cytoskeleton, intracellular communication, membrane transport, metabolism, energy production, or neurotransmission. Overall, it appears that EtOH drinking and the conditions under which EtOH is consumed, differentially affect protein expression levels between the NAcc and AMYG. This may reflect differences in neuroanatomical and/or functional characteristics associated with EtOH self-administration and possibly withdrawal, between these two brain structures.


Assuntos
Consumo de Bebidas Alcoólicas/metabolismo , Tonsila do Cerebelo/metabolismo , Depressores do Sistema Nervoso Central/administração & dosagem , Etanol/administração & dosagem , Núcleo Accumbens/metabolismo , Proteínas/metabolismo , Tonsila do Cerebelo/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Depressores do Sistema Nervoso Central/farmacologia , Proteínas do Citoesqueleto/metabolismo , Esquema de Medicação , Eletroforese em Gel Bidimensional , Enzimas/metabolismo , Etanol/farmacologia , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Núcleo Accumbens/efeitos dos fármacos , Mapeamento de Peptídeos , Proteômica/métodos , Ratos , Ratos Endogâmicos , Autoadministração , Fatores de Tempo
2.
Toxicol Lett ; 160(1): 8-21, 2005 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-16019166

RESUMO

Dermal exposure to jet fuel is a significant occupational hazard. Previous studies have investigated its absorption and disposition in skin, and the systemic biochemical and immunotoxicological sequelae to exposure. Despite studies of JP-8 jet fuel components in murine, porcine or human keratinocyte cell cultures, proteomic analysis of JP-8 exposure has not been investigated. This study was conducted to examine the effect of JP-8 administration on the human epidermal keratinocyte (HEK) proteome. Using a two-dimensional electrophoretic approach combined with mass spectrometric-based protein identification, we analyzed protein expression in HEK exposed to 0.1% JP-8 in culture medium for 24 h. JP-8 exposure resulted in significant expression differences (p<0.02) in 35 of the 929 proteins matched and analyzed. Approximately, a third of these alterations were increased in protein expression, two-thirds declined with JP-8 exposure. Peptide mass fingerprint identification of effected proteins revealed a variety of functional implications. In general, altered proteins involved endocytotic/exocytotic mechanisms and their cytoskeletal components, cell stress, and those involved in vesicular function.


Assuntos
Hidrocarbonetos/farmacologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Células Cultivadas , Eletroforese em Gel Bidimensional , Humanos , Hidrocarbonetos/toxicidade , Processamento de Imagem Assistida por Computador , Interleucina-8/biossíntese , Exposição Ocupacional , Mapeamento de Peptídeos , Proteoma/biossíntese , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
3.
Eur J Gastroenterol Hepatol ; 13(8): 957-62, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11507362

RESUMO

OBJECTIVE: Arterial vasodilation with concomitant hyperdynamic circulation are common findings in liver cirrhosis. Nitric oxide acting at a local level has been suggested to be pathophysiologically relevant in this context. Several systemic factors in conjunction with nitric oxide might interfere with the observed phenomena. DESIGN: The study has been designed to demonstrate the influence of cirrhotic serum on the nitric oxide system and vascular contractility. METHODS: The contractile response of aortic segments from healthy rats was studied in vitro after incubation with serum of healthy and cirrhosis-induced rats (1 week, 2 weeks, 3 weeks and 4 weeks after bile duct ligation). A cumulative dose response curve to phenylephrine (10--10-4 mol) was established before and after incubation with nitric oxide synthesis blocker N(omega)-nitro-L-arginine, the more selective aminoguanidine (nitric oxide synthase [NOS]-2 inhibitor) and W7 (NOS-3 inhibitor). NOS-2 expression in incubated aortic rings was evaluated by Western blot analysis. RESULTS: A 4-hour incubation with serum of cirrhosis-induced rats reduced the maximum contractile response to phenylephrine to 66.8 +/- 9.1% after 1 week, 50.4 +/- 7.8% after 2 weeks, 43.2 +/- 2.8% after 3 weeks and 35 +/- 5.2% after 4 weeks of bile duct ligation. This reduction in the contractility response to phenylephrine was completely reversed by blocking nitric oxide synthesis with N(omega)-nitro-L-arginine and aminoguanidine, but not after W7. Incubation with cirrhotic serum induced NOS-2 expression in aortic rings. In Western blot analysis, the most intensive signal for NOS-2 protein was obtained in rings incubated with serum from rats 3 weeks and 4 weeks after induction of cirrhosis. CONCLUSIONS: Cirrhotic serum decreases the contractile response to phenylephrine even in an early stage of secondary cirrhosis. Reversibility of this effect after nitric oxide synthesis blockade suggests an induction of nitric oxide synthesis by systemic factors as a major point in vascular hyporeactivity to vasoconstrictors in cirrhosis.


Assuntos
Aorta/fisiologia , Cirrose Hepática Experimental/sangue , Óxido Nítrico/fisiologia , Vasoconstrição/fisiologia , Animais , Aorta/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Guanidinas/farmacologia , Técnicas In Vitro , Cirrose Hepática Experimental/fisiopatologia , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II , Nitroarginina/farmacologia , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Sulfonamidas/farmacologia , Vasoconstritores/farmacologia , Vasodilatadores/farmacologia
6.
J Anat ; 196 ( Pt 1): 41-54, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10697287

RESUMO

The vocal ligaments insert at the anterior and posterior commissures of the larynx. These structures fulfil biomechanical functions, balancing the different elastic moduli of tendon, cartilage or bone and undergo age-related changes that may be responsible for voice changes with increasing age. The aim of this study was to analyse the insertion structures of the vocal ligaments by means of macroscopic, histological, immunohistochemical and electron-microscopic methods and to draw conclusions from age-related structural changes on a functional basis. Investigations were carried out on the larynges of 22 males and 15 females (aged 1-95 y). In adolescence, the insertion zone of the vocal ligament tendon, a dense network of connective tissue rich in sulphated glycosaminoglycans at the thyroid cartilage, is characterised by a layer between tendon and cartilage comparable to fibrocartilage. The insertion zone lacks a perichondrium. Collagen fibrils of the vocal ligament tendon penetrate directly into the thyroid cartilage. In the insertion area, the chondrocytes are surrounded by collagen fibrils, which show positive reactivity to antibodies against type I and type III collagen. Sulphated glycosaminoglycans are integrated between the collagen fibrils. In the area of the posterior glottis, elastic cartilage rests like a cap on the hyaline base of the arytenoid cartilage. There is no distinctive border between the structures. With increasing age, ossification of the laryngeal skeleton occurs, involving hyaline cartilage at the posterior glottis and hyaline and fibrocartilage at the anterior commissure. At the same time, a loss or sulphated glycosaminoglycans is observed inside the vocal ligament tendon. Advanced ossification of the laryngeal skeleton, particularly in the area of the commissures, an increasing loss of glycosaminoglycans in the vocal ligament tendon and changes in the elastic tissue reduce the elastic modulus between tendon, cartilage and bone, thus 'stiffening' the insertion zones, which could be one factor among others favouring voice changes with advancing age.


Assuntos
Envelhecimento/fisiologia , Prega Vocal/anatomia & histologia , Humanos , Microscopia , Microscopia Eletrônica
7.
Anat Embryol (Berl) ; 199(4): 281-90, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10195303

RESUMO

Thyroid cartilages of Munich minipigs and domestic pigs were investigated by polychrome sequential labeling, radiography, intravascular injections, histologic examination and scanning electron microscopy in order to gain further insight into the process of vascularization and cartilage mineralization. The relationship between vascularization and cartilage mineralization has only been studied in chondroepiphyses of long bones. Vessels branch off the perichondrial vascular network and enter parts of the thyroid cartilage with a large transverse diameter. Cartilage canals, which are perichondral invaginations, contain an arteriole, a venule, a capillary network and connective tissue. The capillaries form a glomerulus-like structure deep in the matrix of the cartilage. Neighbouring cartilage canals do not display any anastomoses. Cartilage mineralization occurs in large areas of the thyroid cartilage. It is only found in the interterritorial extracellular matrix. Mineralization of the cartilage is evident in areas supplied with cartilage canals as well as in non-supplied areas. Mineralized interterritorial matrix is composed of circular structures of different sizes fusing to form plaques. In scanning electron microscopy circular structures appear as globules. It is possible to visualize the dynamic process of cartilage mineralization with polychrome sequential labeling; it proceeds up to 4 microm per week. Distribution of cartilage canals reveals their nutritional role for the cartilage. According to investigations in chondroepiphyses, cartilage mineralization starts adjacent to the glomerular end of cartilage canals. In contrast, no correlation between cartilage vascularization and the beginning of cartilage mineralization of the thyroid cartilage of Munich minipigs and of domestic pigs has been found.


Assuntos
Calcificação Fisiológica , Cartilagem Tireóidea/irrigação sanguínea , Cartilagem Tireóidea/fisiologia , Animais , Microscopia Eletrônica , Suínos , Porco Miniatura , Fatores de Tempo
8.
Scand J Gastroenterol ; 33(3): 314-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9548627

RESUMO

BACKGROUND: Nitric oxide (NO) may be heavily involved the phenomenon of arterial vasodilation in cirrhosis. However, the subject is still controversial. AIM: This study therefore characterizes the dynamic role of the NO system during development of experimental cirrhosis. METHODS: The contractile response to phenylephrine of thoracic rat aortic rings was studied in vitro before and after nitric oxide blockade. Experiments were performed 1, 2, 3, and 4 weeks after induction of cirrhosis via bile duct ligation with an appropriate control group. RESULTS: In bile duct-ligated rats reduction of the maximum contractile response to phenylephrine was 4.4 +/- 7.3% after 1 week, 22.7 +/- 8.7% after 2 weeks, 48.4 +/- 8.3% after 3 weeks, and 64.6 +/- 8.9% after 4 weeks, in comparison with the control group. This reduction in contractility to phenylephrine was completely reversed by blocking NO synthesis. CONCLUSION: The data presented indicate a dynamic decrease in contractile response to phenylephrine even at an early stage of secondary cirrhosis. Reversibility of the effect after NO synthesis blockade suggests that increased NO synthesis is a major factor in vascular hyporeactivity to vasoconstrictors in cirrhosis.


Assuntos
Artérias/fisiologia , Cirrose Hepática Biliar/fisiopatologia , Óxido Nítrico/fisiologia , Fenilefrina/farmacologia , Vasoconstrição/fisiologia , Vasoconstritores/farmacologia , Animais , Artérias/efeitos dos fármacos , Ductos Biliares , Técnicas In Vitro , Ligadura , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/farmacologia , Ratos , Ratos Sprague-Dawley , Estatísticas não Paramétricas , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
9.
Curr Eye Res ; 11(4): 297-306, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1526163

RESUMO

Because trabecular cell loss is thought to play a role in the pathogenesis of some forms of glaucoma, identification of factors which influence trabecular cell division may provide some insight into the mechanisms and potential treatment of this disease. We studied several commonly encountered clinical situations which may affect the trabecular meshwork: phagocytosis of debris, hyphema, and argon laser trabeculoplasty. The effect of these factors on trabecular cell division was determined using 3H-thymidine autoradiography. Laser trabeculoplasty induced a 307% increase in 3H-thymidine labelling of trabecular cells while phagocytosis and hyphema had no effect on cell labelling. In addition, subgroups of eyes with a loss of trabecular cells or with inflammation did not have increased labelling. Thus laser trabeculoplasty, known to increase outflow facility, was associated with increased trabecular cell labelling while factors often associated with decreased outflow facility and glaucoma were not.


Assuntos
Autorradiografia , Malha Trabecular/citologia , Animais , Gatos , Contagem de Células , Divisão Celular/fisiologia , Replicação do DNA/fisiologia , Glaucoma/patologia , Hifema/fisiopatologia , Terapia a Laser , Fagocitose/fisiologia , Trabeculectomia
10.
Violence Vict ; 6(4): 283-98, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1822698

RESUMO

The present research demonstrates what others have suspected: Protestant fundamentalism is closely linked to favorable attitudes toward corporal punishment of children in the home and the school. The relationship persists with controls for socioeconomic and demographic variables. Three explanations of the greater support for corporal punishment among people affiliated with fundamentalist denominations are tested. Greater personal religiosity and adherence to a punitive image of God account for very little of the relationship. Instead, the emphasis on biblical literalness among fundamentalists appears to be a major source of their advocacy of corporal punishment. Given the potential political effectiveness of fundamentalist churches, the policy implications of these findings present a difficult challenge for those who have called for the prohibition of corporal punishment of children as a crucial step toward reducing the level of violence in our society.


Assuntos
Atitude , Educação Infantil , Cristianismo , Poder Familiar/psicologia , Punição , Religião e Psicologia , Adulto , Criança , Feminino , Humanos , Masculino , Relações Pais-Filho
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