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1.
Pathologe ; 34(2): 118-32, 2013 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23440290

RESUMO

Motility disorders of the esophagus comprise a heterogeneous spectrum of diseases. Primary malformations of the esophagus are now amenable to improved surgical and gastroenterological therapies; however, they often lead to persistent long-term esophageal dysmotility. Achalasia originates from impaired relaxation of the gastroesophageal sphincter apparatus. Systemic diseases may give rise to secondary disorders of esophageal motility. A number of visceral neuromuscular disorders show an esophageal manifestation but aganglionosis rarely extends into the esophagus. The growing group of myopathies includes metabolic and mitochondrial disorders with increasing levels of genetic characterization and incipient emergence of therapeutic strategies. Esophagitis with an infectious etiology causes severe dysmotility particularly in immunocompromised patients. Immunologically mediated inflammatory processes involving the esophagus are increasingly better understood. Finally, rare tumors and tumor-like lesions may impair esophageal motor function.


Assuntos
Transtornos da Motilidade Esofágica/diagnóstico , Transtornos da Motilidade Esofágica/patologia , Diagnóstico Diferencial , Acalasia Esofágica/diagnóstico , Acalasia Esofágica/etiologia , Acalasia Esofágica/patologia , Acalasia Esofágica/fisiopatologia , Transtornos da Motilidade Esofágica/etiologia , Transtornos da Motilidade Esofágica/fisiopatologia , Esôfago/patologia , Esôfago/fisiopatologia , Humanos , Fatores de Risco
3.
Hautarzt ; 56(3): 265-9, 2005 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-15619082

RESUMO

With the occurrence of unclear consciousness conditions primarily internal or neurological causes are considered. Of a systemic mastocytosis one thinks only rarely, which can accompany without or with slight clinically visible skin changes. In the following we report on a patient who has repeated unclear shock conditions and required resuscitation several times without a recognizable cause, with whom a systemic mastocytosis could be proven. Clinically very discrete lesions of mastocytosis were recognizable from the skin. Only an increased tryptase level referred to being present an occult systemic mastocytosis. The diagnostics, potential triggers and therapy of this disease are to be discussed on the basis the available case.


Assuntos
Anafilaxia/diagnóstico , Anafilaxia/etiologia , Mastocitose Cutânea/complicações , Mastocitose Cutânea/diagnóstico , Mastocitose Sistêmica/complicações , Mastocitose Sistêmica/diagnóstico , Ressuscitação , Adulto , Anafilaxia/sangue , Serviços Médicos de Emergência/métodos , Humanos , Masculino , Mastocitose Cutânea/sangue , Mastocitose Sistêmica/sangue , Serina Endopeptidases/sangue , Triptases
4.
Onkologie ; 24(5): 470-5, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11694774

RESUMO

BACKGROUND: The thinking in health psychology is that patients' willingness to adopt preventive health behavior is contingent on their perceiving an increased risk of disease and is influenced by accompanying psychological stress. In counseling women with a family history of breast cancer, physicians focus on encouraging the patient to undergo early detection examinations as recommended. Therefore, it is essential to examine how women in this risk group perceive their own chances of developing breast cancer and to assess the psychological effects of their situation. MATERIAL AND METHODS: 129 women with at least one first or second degree relative who had developed breast cancer were enrolled in a questionnaire study. The object was to ascertain the extent to which these women may be expected to realistically estimate their own probability of contracting the disease and what influence risk perception and psychological strain have on their willingness to make use of diagnostic opportunities for early detection. Additionally, the effects on their physical and mental well-being were analyzed. RESULTS: Among the women of the study group, a family history of breast cancer did not always correlate with the subject's perception of an increased risk of contracting the disease compared. On the whole, the majority of the women overestimated their personal risk despite prior genetic counseling. Only slightly less than one quarter of the study group correctly estimated their risk; another quarter underestimated it. The majority of those women who exhibited an increased risk perception were also those who overestimated their probability of personally contracting the disease. They underwent recommended screening examinations significantly less often than women with a low risk perception. However, women subjected to intense psychological strain showed above-average participation in screening programs. CONCLUSIONS: Women with a family history of breast cancer often find it difficult to realistically estimate their own risk of contracting the disease. Increased risk perception had a negative effect on participation in recommended breast cancer screening. Therefore, an effort should be made to correct the patient's overestimation of her personal risk. Integrating psychological counseling in screening programs is essential considering that women from high-risk groups are subjected to increased psychological strain. Further studies are required to more precisely evaluate other psychosocial factors in the behavior of women in risk group toward screening.


Assuntos
Atitude Frente a Saúde , Neoplasias da Mama/genética , Programas de Rastreamento/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Estresse Psicológico/complicações , Adulto , Idoso , Neoplasias da Mama/prevenção & controle , Neoplasias da Mama/psicologia , Feminino , Predisposição Genética para Doença/genética , Predisposição Genética para Doença/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Medição de Risco
5.
Am J Surg ; 181(3): 204-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11376571

RESUMO

BACKGROUND: Open tension-free techniques of hernia repair using synthetic meshes revealed an excellent patient comfort with low recurrence rates. The influence of the resulting fibrosis on testicular perfusion and sexual function is still unclear. METHODS: In a prospective observation study testicular volume, perfusion, and sexual function was investigated before plug and patch repair, after 3 months, and every 6 months thereafter. Testicular volume and perfusion was examined by a standardized scrotal ultrasound and duplex sonography. Sexual function was assessed by a validated anonymized questionnaire. RESULTS: Seventy-three patients were included and follow-up examinations by questionnaire and sonography, respectively, were completed in 73 and 68 patients after 3 months, 51 and 43 after 6, and 24 and 14 after 12 months. Preoperative testicular volume and flow volume was comparable between the side of hernia and the contralateral side (average 10.2 +/- 4.8 cm3 versus 9.8 +/- 5.3, respectively) and showed no significant differences during follow-up. In 11 (15%) patients with preexisting disorders sexual function was normalized postoperatively. Ten (14%) other patients (3 of them with neuralgia pain) described limitations of sexual activity due to inguinal pain (n = 4; 6%) or a loss of sensitivity in the inguinal area (n = 6; 8%) after the procedure. Among these, sexual function recovered spontaneously within 12 months postoperatively in 6 patients (2 with inguinal pain, 4 with loss of sensitivity). In all other patients sexual function showed no changes after inguinal hernia repair. CONCLUSIONS: So far there is no evidence for a significant impairment of the cord structures and the sexual function after inguinal hernia repair in the plug and patch technique.


Assuntos
Hérnia Inguinal/cirurgia , Complicações Pós-Operatórias/etiologia , Disfunções Sexuais Fisiológicas/etiologia , Telas Cirúrgicas , Testículo/irrigação sanguínea , Hérnia Inguinal/complicações , Hérnia Inguinal/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Estudos Prospectivos , Escroto/diagnóstico por imagem , Disfunções Sexuais Fisiológicas/diagnóstico , Estatísticas não Paramétricas , Inquéritos e Questionários , Testículo/diagnóstico por imagem , Resultado do Tratamento , Ultrassonografia Doppler em Cores
6.
Biol Reprod ; 64(6): 1689-94, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11369596

RESUMO

Plasmalogens are a main component of the spermatozoon membrane, playing a crucial role in their maturation. The initial steps in plasmalogen biosynthesis are catalyzed by two peroxisomal enzymes, dihydroxyacetonephosphate acyltransferase and alkyl-dihydroxyacetonephosphate synthase. The localization of both enzymes in the membrane of peroxisomes implies that plasmalogen-producing cells should contain this organelle. To unravel the putative source of spermatozoan plasmalogens we investigated which cell types in the testis and epididymis are endowed with peroxisomes. To this extent, testicular and epididymal tissue was analyzed at the protein and RNA levels by means of light and electron microscopical immunocytochemistry as well as by Western and Northern blotting. Proteins and mRNAs of peroxisomal enzymes, especially those of dihydroxyacetonephosphate acyltransferase and alkyl-dihydroxyacetonephosphate synthase, were detected in the testis and epididymis. In the testis, peroxisomes were localized exclusively in Leydig cells and not in cells of the seminiferous tubules, implying that the latter do not contribute to the biosynthesis of plasmalogens of the sperm membrane. In contrast, peroxisomes could be clearly visualized in the epithelial cells of the epididymis. The results suggest that peroxisomes in epithelial cells of the rat epididymis play a pivotal role in the biosynthesis of plasmalogens destined for delivery to the sperm plasma membrane.


Assuntos
Peroxissomos/enzimologia , Plasmalogênios/biossíntese , Testículo/ultraestrutura , Aciltransferases/genética , Aciltransferases/metabolismo , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Animais , Membrana Celular/metabolismo , Epididimo/enzimologia , Células Epiteliais/ultraestrutura , Humanos , Imuno-Histoquímica , Membranas Intracelulares/enzimologia , Células Intersticiais do Testículo/ultraestrutura , Masculino , Microscopia Eletrônica , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Espermatozoides/ultraestrutura
7.
Eur J Cell Biol ; 79(1): 35-40, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10711424

RESUMO

The subcellular compartmentalization of urate oxidase (UOX) in the digestive glands of mussels, Mytilus galloprovincialis Lmk, was studied by means of immunoblotting and immunocytochemistry, using an antibody raised in rabbit against rat liver UOX. Western blot analysis of subcellular fractions revealed an immunoreactive polypeptide with a molecular weight similar to the corresponding mammalian hepatic protein. This crossreactive polypeptide of 32 kDa was particle-bound yet not peroxisome-associated. In paraffin sections the antiserum specifically labeled the plasma membrane of the digestive gland epithelial cells and discrete regions within the perinuclear and apical portions of the digestive tubules and duct cells. By electron microscopy gold particles representing antigenic sites were found on the microvilli and the lateral plasma membrane as well as the membranes of the secretory/ endocytic compartments, that is, the Golgi complex, secretory and some endocytic vesicle membranes. Since the peroxisomal UOX-antibody exhibits a comparable immunoreactivity towards a urate-transporter channel protein in rat kidney proximal tubules and has been used for its molecular cloning (Leal-Pinto et al., 1997, J. Biol. Chem. 272, 617-625), we suggest that the membrane protein identified in mussel digestive glands could represent a homologous urate-transporter protein.


Assuntos
Bivalves/enzimologia , Urato Oxidase/análise , Animais , Bivalves/ultraestrutura , Western Blotting/métodos , Compartimento Celular , Membrana Celular/enzimologia , Imuno-Histoquímica , Microscopia Imunoeletrônica/métodos , Coelhos , Ratos , Frações Subcelulares
8.
Histochem Cell Biol ; 113(1): 51-60, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10664070

RESUMO

Peroxisomes of the digestive glands of mussels, Mytilus galloprovincialis Lmk, were investigated by immunoblotting and immunohistochemistry using rabbit antibodies against several mammalian hepatic peroxisomal proteins. Western blot analysis of main subcellular fractions revealed immunoreactive polypeptides with molecular weights comparable to those of the corresponding mammalian hepatic proteins. They could be localized to the peroxisomal matrix in the case of catalase, multifunctional enzyme (PH), and palmitoyl-CoA oxidase (AOX), and to the peroxisomal membrane in respect to PMP 70. The purification of peroxisomes by metrizamide density gradient centrifugation revealed the existence of two subpopulations with densities of 1.16 and 1.20 g cm(-3) exhibiting different protein compositions. In paraffin sections, positive immunolabeling for catalase was distributed along the apical cytoplasm of the epithelia of digestive ducts and stomach and throughout the cytoplasm of digestive tubule cells. The peroxisomal beta-oxidation enzymes, AOX and PH, also appeared predominantly in the ducts and the stomach epithelia with a weaker immunolabeling in the tubules. At the electron microscopic level a clear labeling with gold particles was observed in the peroxisomal matrix with the anti-guinea pig catalase antibody. In addition to peroxisomes, the anti-PH antibody also labeled the mitochondria. The similarity in the protein composition of molluscan and mammalian peroxisomes as revealed by the present study indicates that those proteins have been well conserved in evolution suggesting that functionally peroxisomes in molluscs could also be involved in the metabolism of lipids and in detoxification of xenobiotics. Thus, the antibodies tested could provide useful tools for detection of peroxisomal induction in molluscan biomonitoring programs for the assessment of aquatic environmental pollution.


Assuntos
Bivalves/enzimologia , Peroxissomos/enzimologia , Acetil-CoA C-Aciltransferase/análise , Aminoácido Oxirredutases/análise , Animais , Bivalves/ultraestrutura , Western Blotting , Catalase/análise , Catalase/ultraestrutura , Fracionamento Celular , Sistema Digestório/enzimologia , Sistema Digestório/ultraestrutura , Cobaias , Imuno-Histoquímica , Microscopia Imunoeletrônica , Complexos Multienzimáticos/análise , Complexos Multienzimáticos/ultraestrutura , Oxirredutases/análise , Peroxissomos/ultraestrutura , Coelhos
9.
Eur J Immunol ; 30(12): 3707-17, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11169414

RESUMO

Recently, we have identified the inducible co-stimulator (ICOS), an activation-dependent, T cell-specific cell surface molecule related to CD28 and CTLA-4. Detailed analysis of human ICOS presented here shows that it is a 55-60-kDa homodimer with differently N-glycosylated subunits of 27 and 29 kDa. ICOS requires both phorbol 12-myristate 13-acetate and ionomycin for full induction, and is sensitive to Cyclosporin A. ICOS is up-regulated early on all T cells, including the CD28- subset, and continues to be expressed into later phases of T cell activation. On stimulation of T cells by antigen-presenting cells, the CD28/B7, but not the CD40 ligand/CD40 pathway is critically involved in the induction of ICOS. ICOS does not bind to B7-1 or B7-2, and CD28 does not bind to ICOS ligand; thus the CD28 and ICOS pathways do not cross-interact on the cell surface. In vivo, ICOS is expressed in the medulla of the fetal and newborn thymus, in the T cell zones of tonsils and lymph nodes, and in the apical light zones of germinal centers (predominant expression). Functionally, ICOS co-induces a variety of cytokines including IL-4, IL-5, IL-6, IFN-gamma, TNF-alpha, GM-CSF, but not IL-2, and superinduces IL-10. Furthermore, ICOS co-stimulation prevents the apoptosis of pre-activated T cells. The human ICOS gene maps to chromosome 2q33 - 34.


Assuntos
Antígenos de Diferenciação de Linfócitos T/fisiologia , Antígenos de Diferenciação de Linfócitos T/genética , Apoptose , Antígeno B7-1/fisiologia , Antígenos CD28/fisiologia , Linfócitos T CD4-Positivos/metabolismo , Antígenos CD40/fisiologia , Linfócitos T CD8-Positivos/metabolismo , Mapeamento Cromossômico , Ciclosporina/farmacologia , Citocinas/biossíntese , Dimerização , Glicosilação , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis
10.
Gerodontology ; 17(2): 104-18, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11808055

RESUMO

UNLABELLED: This paper summarises a series of studies already published in German and presents new data related to the aetiology of the 'dry mouth' and its associated problems. AIMS: To study factors affecting mucous and serous salivary gland secretion, the aetiology of the 'dry mouth' and its associated problems, causative factors for hyposalivation and it's treatment. SETTING: Two university dental hospitals. SUBJECTS: 587 denture wearers and 521 control subjects, and autopsy material. INTERVENTIONS: Exercise, chewing, water, oestrogen, pilocarpine, and anetholtrithion therapy, biopsy of the minor glands. MAIN OUTCOME MEASURES: Palatal secretion (PAL, microL/cm2/min) and parotid salivary flow (PAR), subjective complaints and clinical findings. RESULTS: Resting flow rates for PAL between 0 and 65 microliters/cm2/min were seen in every age group. The flow rates of PAR (0 to 3.7 ml/10 min) were not correlated with PAL. Most patients with a resting flow rate of PAL < or = 6.0 microliters/cm2 suffer from a 'dry mouth' and Burning Mouth Syndrome (BMS) or oral dysaesthesia (OD) with or without chronic lesions of the oral mucosa. Etiological factors for the incidence of reduced PAL and associated problems include xerostomic drugs, oestrogen deficiency, radiotherapy, thyroid dysfunction, smoking or continuous wearing of complete upper dentures. PAL also correlated with the retention of upper complete dentures. PAL was correlated with the water content of epithelial tissues. PAL and PAR were both increased by drinking ample fluid, improving their circulation by physical exercises, chewing intensively, or taking oestrogens, pilocarpine, anetholtrithion. CONCLUSIONS: Variation in palatal salivary secretion occurs and is clinically important.


Assuntos
Síndrome da Ardência Bucal/fisiopatologia , Retenção de Dentadura , Saliva/metabolismo , Glândulas Salivares Menores/fisiopatologia , Xerostomia/fisiopatologia , Adulto , Idoso , Envelhecimento , Síndrome da Ardência Bucal/complicações , Colagogos e Coleréticos/farmacologia , Estrogênios/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agonistas Muscarínicos/farmacologia , Palato , Parestesia/fisiopatologia , Glândula Parótida/fisiopatologia , Reologia/instrumentação , Saliva/efeitos dos fármacos , Glândulas Salivares Menores/efeitos dos fármacos , Glândulas Salivares Menores/metabolismo , Xerostomia/complicações
11.
Virchows Arch ; 435(5): 486-95, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10592052

RESUMO

A significant reduction of catalase activity, a peroxisomal marker enzyme, occurs in human hepatic neoplasias, but no information is available on other peroxisomal proteins. We have studied by means of immunohistochemistry four specific proteins of peroxisomes (catalase and three enzymes of lipid beta-oxidation) in human hepatocellular tumors of various differentiation grades from adenoma to anaplastic carcinoma. In all tumors, except the adenomas, the tumor cells contained fewer peroxisomes than extrafocal hepatocytes and the reduction of antigenic sites in the tumor types generally correlated with the degree of tumor dedifferentiation as assessed by classical histopathological criteria. Two poorly differentiated tumors had no detectable peroxisomes at all. There were no major differences in the intensities of the immunocytochemical staining for all four studied peroxisomal antigens in different tumors, suggesting that the neoplastic transformation affects the biogenesis of the entire organelle and not merely the individual peroxisomal enzyme proteins. Some tumors exhibited a distinct peripheral distribution of peroxisomes. In cases with associated liver cirrhosis, the hepatocytes in the adjacent liver showed marked peroxisome proliferation, forming large perinuclear aggregates, occupying occasionally the entire cytoplasm. Taken together, our observations indicate that peroxisomes are significantly altered in both hepatocellular tumors and liver cirrhosis and, thus, could be responsible for some of the metabolic derangements observed in those disease processes.


Assuntos
Adenoma de Células Hepáticas/enzimologia , Carcinoma Hepatocelular/enzimologia , Catalase/metabolismo , Cirrose Hepática/enzimologia , Neoplasias Hepáticas/enzimologia , Peroxissomos/enzimologia , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Acetil-CoA C-Aciltransferase/metabolismo , Acil-CoA Oxidase , Adenoma de Células Hepáticas/ultraestrutura , Carcinoma Hepatocelular/ultraestrutura , Enoil-CoA Hidratase/metabolismo , Humanos , Imuno-Histoquímica , Isomerases/metabolismo , Metabolismo dos Lipídeos , Cirrose Hepática/patologia , Neoplasias Hepáticas/ultraestrutura , Complexos Multienzimáticos/metabolismo , Oxirredutases/metabolismo , Enzima Bifuncional do Peroxissomo
12.
Carcinogenesis ; 20(6): 985-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10357777

RESUMO

Peroxisomes and the activities of their enzymes have been reported to be significantly reduced in various types of tumors including the colon carcinoma. Therefore, the present study was designed to investigate the gene expression of several peroxisomal proteins in human colon carcinoma and additionally those of the peroxisome proliferator activated receptor alpha (PPARalpha) and PEX5, a receptor protein involved in the import of most peroxisomal matrix proteins. Samples from adenocarcinomas and adjacent normal colon were analyzed by immunohistochemistry and western blotting. The mRNA content was assessed by a novel sensitive dot blot RNase protection assay and northern blotting. By immunohistochemistry, peroxisomes were distinctly visualized in normal colonocytes but were not detected in colon carcinoma cells. The protein levels of catalase (CAT), acyl-CoA oxidase as well as the 22 and 70 kDa peroxisomal membrane proteins (PMP22 and PMP70) were all significantly decreased in carcinomas. The corresponding mRNAs for CAT and PMP70, however, were unchanged. In contrast, the mRNA of PEX5 was significantly increased. The expression of PPARalpha was not altered in tumors, neither at protein nor mRNA levels. These observations show that the reduction of peroxisomes and their proteins in colon carcinoma is not due to a generalized reduction of transcription of their genes. It seems more likely that this phenomenon is regulated at a post-transcriptional or translational level. Alternatively, and more likely, an impairment of the biogenesis of the organelle could account for the paucity of peroxisomes in colon carcinoma.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Adenocarcinoma/ultraestrutura , Neoplasias do Colo/ultraestrutura , Microcorpos , Acil-CoA Oxidase , Adenocarcinoma/enzimologia , Adenocarcinoma/metabolismo , Catalase/genética , Catalase/metabolismo , Neoplasias do Colo/enzimologia , Neoplasias do Colo/metabolismo , Humanos , Imuno-Histoquímica , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microcorpos/enzimologia , Microcorpos/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Receptor 1 de Sinal de Orientação para Peroxissomos , RNA Mensageiro/genética , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
13.
Int J Cancer ; 79(3): 232-40, 1998 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-9645343

RESUMO

Preneoplastic liver foci and neoplasms of different morphological phenotypes were induced in rats with N-nitrosomorpholine (NNM; 120 mg/l in drinking water for 7 weeks) and the peroxisome proliferator dehydroepiandrosterone (DHEA; 0.6% in the diet for up to 84 weeks). Preneoplastic glycogen storage foci (GSF) occurred mainly upon treatment with NNM, and amphophilic cell foci (APF) were mainly observed in rats treated with DHEA alone or in combination with NNM. The 2 types of lesions belong to 2 different cellular lineages, the glycogenotic/basophilic lineage and the amphophilic lineage, which are characterized by distinct patterns of alterations in key enzymes of energy metabolism. Whereas in GSF enzymes of glucose metabolizing pathways were modified (increase in glucose-6-phosphate dehydrogenase and pyruvate kinase, decrease in glucose-6-phosphatase), APF mainly demonstrated alterations in mitochondrial enzymes (increase in cytochrome c oxidase, succinate dehydrogenase and glycerol-3-phosphate dehydrogenase) and, to a lower extent, in peroxisomal enzymes (increase in peroxisomal hydratase and acyl-CoA oxidase). The alterations in enzyme expression reflect an insulinomimetic effect in GSF and a thyromimetic effect in APF. Neoplasms resulting from APF show a more differentiated phenotype than those arising from GSF. We suggest that the different and in many aspects opposite effects of the 2 carcinogens on key enzymes of distinct pathways of energy metabolism modulate the process of neoplastic liver cell transformation and result in phenotypically different preneoplasias and neoplasias reflecting different cellular lineages.


Assuntos
Neoplasias Hepáticas Experimentais/enzimologia , Lesões Pré-Cancerosas/enzimologia , Animais , Carcinógenos , Desidroepiandrosterona , Metabolismo Energético , Feminino , Glucosefosfato Desidrogenase/metabolismo , Glicogênio/análise , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Microcorpos/enzimologia , Mitocôndrias Hepáticas/enzimologia , Morfolinas , Lesões Pré-Cancerosas/induzido quimicamente , Piruvato Quinase/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Carcinogenesis ; 18(8): 1491-8, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9276621

RESUMO

Dehydroepiandrosterone (DHEA) is an intermediate product in the synthesis of male and female sex hormones in the adrenal cortex of man. In livers of rats and mice DHEA increases the levels of cytochrome P450 IVA and peroxisomal beta-oxidation enzymes associated with peroxisome proliferation. Prolonged treatment of rats with DHEA induces liver tumors that are more frequent in females arising mainly in the periportal regions of the liver lobule (Metzger et al., Toxicol. Pathol. 23, 591-605, 1995). Because of paucity of information on hepatic zonation of peroxisomal response to DHEA and controversial reports on gender-specific differences of its effects the present study was undertaken using qualitative immunohistochemical and quantitative immunoelectron microscopical techniques in addition to Western blotting. Rats were treated for 24 weeks with 0.6% DHEA supplied with diet. Immunoblot analysis revealed marked induction of peroxisomal beta-oxidation enzymes, which by quantitative analysis was equally strong in male and female animals, whilst catalase and urate-oxidase were not increased. Cytochrome P450 IVA, in contrast, was induced significantly stronger in male than in female rats. Immunohistochemistry confirmed the induction of cytochrome P450 IVA showing a marked lobular gradient in female animals with strong induction in pericentral and almost no induction in periportal regions of the liver lobule. In male animals cytochrome P450 IVA was expressed more uniformly across the liver lobule. A similar sex specific zone-dependent response was observed for peroxisomes. DHEA induced in females a significant zonal gradient with marked peroxisome proliferation and a strong induction of peroxisomal hydratase/dehydrogenase in pericentral hepatocytes and a much smaller response in periportal regions. Livers of male animals, in contrast, showed a uniform peroxisomal proliferation to DHEA with only slight zonal differences. The striking homologies of the induction patterns of cytochrome P450 IVA and the peroxisome proliferation in both sexes support the notion of a functional relationship. In view of the almost exclusive periportal localization of DHEA-induced tumors in female rats in contrast to the pericentral localization of the peroxisomal proliferation shown by this study, it seems likely that other factors in addition to peroxisome proliferation may contribute to the hepatocarcinogenic effect of DHEA.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Desidroepiandrosterona/farmacologia , Enzimas/metabolismo , Fígado/enzimologia , Microcorpos/enzimologia , Oxigenases de Função Mista/metabolismo , Acil-CoA Oxidase , Animais , Western Blotting , Catalase/metabolismo , Citocromo P-450 CYP4A , Feminino , Imuno-Histoquímica , Masculino , Microscopia Imunoeletrônica , Complexos Multienzimáticos/metabolismo , Oxirredutases/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Urato Oxidase/metabolismo
15.
FEBS Lett ; 412(2): 385-7, 1997 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-9256257

RESUMO

We have studied the effects of TNF-alpha on the mRNAs coding for the peroxisome proliferator activated receptor alpha (PPAR-alpha), and for catalase (Cat), acyl-CoA oxidase (AOX), multifunctional enzyme (PH), and beta-actin in rat liver. Total RNA was isolated from livers of male SD-rats 16 h after administration of a single dose of 25 microg TNF-alpha and mRNAs were analyzed by a novel dot blot RNase protection assay. The mRNAs for PPAR-alpha and for Cat, AOX and PH were significantly reduced by TNF-treatment. In addition, the level of PPAR-alpha protein was also decreased after TNF. In contrast, the mRNA for beta-actin was markedly increased implying that the effect of TNF on PPAR-alpha and the peroxisomal mRNAs is highly selective. This effect may have important implications in perturbation of the lipid metabolism induced by TNF-alpha.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Fígado/metabolismo , Microcorpos/metabolismo , RNA Mensageiro/genética , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição/genética , Fator de Necrose Tumoral alfa/farmacologia , Actinas/genética , Acil-CoA Oxidase , Animais , Catalase/genética , Masculino , Complexos Multienzimáticos/genética , Oxirredução , Oxirredutases/genética , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia
16.
J Emerg Med ; 15(3): 303-7, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9258778

RESUMO

Actinomycosis is a chronic-suppurative disease characterized by abscesses and draining sinus tracts, with fibrosis and granulation involving the face and neck and thoracic or pelvic-abdominal regions. Dermatological findings in patients at high risk are the key to the correct diagnosis. Actinomycosis is frequently undiagnosed or misdiagnosed until the correct diagnosis is made after surgical resection. Alcoholic, homeless, and disadvantaged individuals and patients with other factors predisposing to infection including poor dentition, alcoholism, seizures, and trauma are common in the emergency department; thus, emergency physicians should be aware of the different presentations and complications of this disease. The treatment of choice is a high dose of penicillin in conjunction with surgical debridement. The prognosis is excellent with correct diagnosis and therapy.


Assuntos
Actinomicose Cervicofacial/complicações , Empiema Pleural/microbiologia , Derrame Pleural/microbiologia , Actinomicose Cervicofacial/diagnóstico , Actinomicose Cervicofacial/tratamento farmacológico , Alcoolismo/complicações , Biópsia , Causalidade , Diagnóstico Diferencial , Empiema Pleural/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Penicilinas/uso terapêutico , Doenças Periodontais/complicações , Derrame Pleural/diagnóstico por imagem , Radiografia
17.
FEBS Lett ; 310(3): 273-6, 1992 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-1397283

RESUMO

TNF-alpha is a potent cytokine which induces marked hyperlipidemia. Because of the important role of peroxisomes in lipid metabolism we investigated the effects of human recombinant TNF-alpha upon rat liver peroxisomal enzymes. Sixteen hours after the administration of a single dose of 25 micrograms of TNF-alpha to male rats the activity of peroxisomal fatty acyl-CoA oxidase was reduced by 50%. This was confirmed also by immunoblotting and by quantitative immunoelectron microscopy which in addition revealed substantial reduction of the trifunctional protein (hydratase-dehydrogenase-isomerase) in peroxisomes. These observations suggest that the suppression of peroxisomal beta-oxidation may contribute to the perturbation of the isomerase) in peroxisomes. These observations suggest that the suppression of peroxisomal beta-oxidation may contribute to the perturbation of the lipid metabolism induced by TNF-alpha.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hiperlipidemias/metabolismo , Isomerases , Metabolismo dos Lipídeos , Microcorpos/enzimologia , Fator de Necrose Tumoral alfa/farmacologia , 3-Hidroxiacil-CoA Desidrogenases/isolamento & purificação , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Acil-CoA Oxidase , Animais , Enoil-CoA Hidratase/isolamento & purificação , Enoil-CoA Hidratase/metabolismo , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/ultraestrutura , Masculino , Microcorpos/efeitos dos fármacos , Complexos Multienzimáticos/isolamento & purificação , Complexos Multienzimáticos/metabolismo , Oxirredutases/metabolismo , Enzima Bifuncional do Peroxissomo , Racemases e Epimerases/isolamento & purificação , Racemases e Epimerases/metabolismo , Ratos , Proteínas Recombinantes/farmacologia
19.
Geburtshilfe Frauenheilkd ; 50(8): 597-604, 1990 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-2170226

RESUMO

There is no agreement in literature on the biological behavior of psammoma carcinomas of the ovary. The majority of authors consider psammoma bodies to be the result of tumour regression, associating the occurrence of psammoma bodies with longer survival. On the other hand, several studies reveal a poor prognosis for psammoma carcinomas, similar to that of other epithelial malignant tumours. In our study, the psammoma body content in 174 serous carcinomas stage III/IV was morphometrically quantified by image analysis and the results correlated to survival time and progression time. In 20 carcinomas the psammoma body content was extremely high. In such cases, DNA flow cytometry revealed these tumours to be slowly-growing. The DNA index was 1.0 (DNA-diploid) and the number of S phases was low (max. 5.9%). The five year estimate survival was 50%, as opposed to 10% for other tumours. If no methods are available for cell kinetic analysis and for objectification and quantification of psammoma body content in serous carcinomas it is sufficient to make a semiquantitative assessment of the psammoma body content to differentiate tumours with longer survival from carcinomas of poor prognosis.


Assuntos
Cistadenoma/patologia , DNA de Neoplasias/análise , Citometria de Fluxo/instrumentação , Processamento de Imagem Assistida por Computador/instrumentação , Neoplasias Ovarianas/patologia , Feminino , Humanos , Corpos de Inclusão/ultraestrutura , Interfase/fisiologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Ovário/patologia , Prognóstico
20.
Biochim Biophys Acta ; 997(3): 236-41, 1989 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-2765561

RESUMO

A series of N-alkylmaleimides varying in chainlength from N-methyl- to N-octylmaleimide inclusive was shown to effectively inactivate sheep liver sorbitol dehydrogenase at pH 7.5 and 25 degrees C. The apparent second-order rate constants for inactivation increased with increasing chainlength of the N-alkylmaleimide used. Positive chainlength effects were also indicated by the Kd values for the N-ethyl and N-heptyl derivatives obtained from studies of the saturation kinetics observed for inactivation of the enzyme at high concentrations of these maleimides. The complete inactivation of sorbitol dehydrogenase was demonstrated to occur through the selective covalent modification of one cysteine residue per subunit of enzyme. The stoichiometry of enzyme inactivation was supported on the one hand by fluorescence titration with fluorescein mercuric acetate of the native and the inactivated enzyme, and, on the other hand, by the simultaneous inactivation of the enzyme with selective modification of one sulfhydryl per subunit by N-[p-(2-benzoxazolyl)phenyl]maleimide. Protection of the enzyme from N-alkylmaleimide inactivation was observed with the binding of NADH, whereas both NAD and sorbitol were ineffective as protecting ligands. Diazotized 3-aminopyridine adenine dinucleotide, in contrast to previous studies of this reagent with yeast alcohol dehydrogenase and rabbit muscle glycerophosphate dehydrogenase, did not function as a site-labeling reagent for sorbitol dehydrogenase.


Assuntos
L-Iditol 2-Desidrogenase/antagonistas & inibidores , Fígado/enzimologia , Maleimidas/farmacologia , Desidrogenase do Álcool de Açúcar/antagonistas & inibidores , Animais , Cinética , Ovinos , Relação Estrutura-Atividade , Compostos de Sulfidrila/metabolismo
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