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1.
Hum Immunol ; 62(10): 1081-91, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11600214

RESUMO

Helicobacter pylori infection is linked to chronic gastritis, peptic ulcer and gastric carcinoma. During H. pylori infection, class II MHC expression by the gastric epithelium increases, as does the number of local CD4(+) T cells, which appear to be important in the associated pathogenesis. These observations suggested that the epithelium might present antigens to T cells. Thus, we sought to determine whether gastric epithelial cells process antigens to establish their function as local antigen presenting cells (APC). We examined a panel of gastric epithelial cell lines for expression of the antigen processing cathepsins B (CB), L (CL), S (CS), and D (CD). The mRNA for these enzymes were detected by RT-PCR and the enzymes in the gastric epithelial cells were identified by various independent methods. We corroborated the expression of CB and CD on gastric epithelial cells from human biopsy samples. The functions of these proteases were confirmed by assessing their ability to digest ovalbumin, a conventional dietary antigen, and proteins from H. pylori. In summary, multiple lines of evidence suggest gastric epithelial cells process antigens for presentation to CD4(+) T cells. To our knowledge, these are the first studies to document the antigen processing capacity of human gastric epithelial cells.


Assuntos
Células Apresentadoras de Antígenos/enzimologia , Células Apresentadoras de Antígenos/imunologia , Catepsina B/biossíntese , Catepsinas/biossíntese , Mucosa Gástrica/enzimologia , Mucosa Gástrica/imunologia , Apresentação de Antígeno , Antígenos de Diferenciação de Linfócitos B/metabolismo , Catepsina B/genética , Catepsina D/biossíntese , Catepsina D/genética , Catepsina L , Catepsinas/genética , Linhagem Celular , Linhagem Celular Transformada , Cisteína Endopeptidases/biossíntese , Cisteína Endopeptidases/genética , Mucosa Gástrica/citologia , Mucosa Gástrica/patologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Hidrólise , Imunidade nas Mucosas , Antro Pilórico/enzimologia , Antro Pilórico/patologia , RNA Mensageiro/biossíntese
2.
Steroids ; 63(11): 556-64, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9830681

RESUMO

The epimers 17 beta-amino-1,3,5(10)-estratrien-3-ol and 17 alpha-amino-1,3,5(10)-estratrien-3-ol were synthesized. 17 beta-Amino-1,3,5(10)-estratrien-3-ol was prepared by catalytic hydrogenation of the estrone-oxime. The 17 alpha-amino epimer was obtained from estradiol, via tosylate, followed by nucleophilic displacement by sodium azide and subsequent reduction with LiAlH4. They were characterized by spectroscopic methods. Determination of the crystal structures of 3-(toluene-4-sulfonyloxy)-17 alpha-1,3,5(10)-estratriene, 3-(toluene-4-sulfonyloxy)-17-alpha-amino,1,3,5(10)-estratriene hydrochloride, 17 beta-acetylamino-1,3,5(10)-estratriene-3-ol, and 3-acetoxy-17 beta-acetylamino-1,3,5(10)-estratriene enabled us to characterize the structure of the 17 alpha and 17 beta amino epimers for the first time.


Assuntos
Congêneres do Estradiol/química , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular
3.
Int Arch Allergy Immunol ; 117(2): 85-93, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9784651

RESUMO

The invariant chain (Ii) due to its intimate association with major histocompatibility complex (MHC) alpha and beta chains is a determining element in the development of immune responses. Ii plays a major role in the assembly, the intracellular transport and peptide selection by class II MHC. A segment of Ii designated as CLIP (class II-associated Ii peptide) binds into the antigen binding site of class II MHC molecules until class II MHC reach intracellular compartments that contain peptides from internalized antigens. This association limits the self endogenous peptides that can bind to class II MHC molecules. The removal of CLIP from class II MHC catalyzes the binding of antigenic peptides and their subsequent cell surface expression. An isoform of Ii, known as chondroitin sulfate-modified Ii (IiCS), that is surface-expressed enhances T cell activation while acting as a coreceptor for CD44. The expression of class II MHC molecules by mucosal epithelial cells has generated interest in the role that these cells may have in mucosal immunity. Since in classical antigen-presenting cells (APC) the biology of class II MHC is regulated by Ii, it is necessary to bring into perspective the known functions of Ii in conventional APC to understand the role that Ii may play in mucosal epithelial cells as potential regulators of local immune responses.


Assuntos
Antígenos de Diferenciação de Linfócitos B/fisiologia , Antígenos de Histocompatibilidade Classe II/fisiologia , Imunidade nas Mucosas , Células Apresentadoras de Antígenos/imunologia , Antígenos de Diferenciação de Linfócitos B/classificação , Células Epiteliais/imunologia , Antígenos de Histocompatibilidade Classe II/classificação , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos
4.
Ginecol Obstet Mex ; 65: 362-7, 1997 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-9410805

RESUMO

The laparoscopically assisted vaginal hysterectomy offers the possibility to convert abdominal to vaginal approach give to the patient the benefits of ti. The analysis of the first 20 cases in our institution is done and are compared with abdominal and vaginal approaches in some parameters including costs, indications and hospitalization days. The laparoscopically assisted vaginal hysterectomy offers to the patient the benefits of the vaginal approach with hospital stay similar and cost and operative time higher than those for either vaginal and abdominal hysterectomy. The exact role of the laparoscopically assisted vaginal hysterectomy on daily practice still is pending.


Assuntos
Histerectomia Vaginal , Histerectomia/métodos , Laparoscopia , Complicações Neoplásicas na Gravidez/cirurgia , Neoplasias Uterinas/cirurgia , Adulto , Feminino , Hospitais Militares , Humanos , México , Pessoa de Meia-Idade , Gravidez , Resultado do Tratamento
5.
Obstet Gynecol ; 83(5 Pt 1): 732-4, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8164933

RESUMO

OBJECTIVE: To evaluate the clinical effectiveness and safety of a thermal balloon system to ablate the endometrium. METHODS: All 18 patients were candidates for hysteroscopic endometrial ablation or hysterectomy for menorrhagia and consented to a trial of the balloon technique of ablation. All procedures were done in the operating room under general anesthesia, except in one patient who had regional and another who had local anesthesia with analgesia. Follow-up of 6-34 months is reported. RESULTS: Fifteen subjects (83%) reported significant reduction in bleeding or amenorrhea. Two patients underwent subsequent hysterectomy and one a follow-up hysteroscopic examination with biopsy. Histology in these three cases showed areas of scar as well as areas of normal endometrial histology. In one uterus, the entire cavity and the endometrium were normal. The others had endometrial bands of scar and some contraction of the cavity. CONCLUSIONS: Based on follow-up results, the frequency of successful reduction of bleeding and/or amenorrhea in this small series is comparable to hysteroscopic methods of endometrial ablation. There were no complications. A larger trial is warranted to compare this method to hysteroscopic endometrial ablation.


Assuntos
Ablação por Cateter , Temperatura Alta/uso terapêutico , Menorragia/terapia , Endométrio/patologia , Feminino , Seguimentos , Humanos
6.
Steroids ; 58(10): 457-61, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8256254

RESUMO

The syntheses and characterizations of two new 17 beta-aminoestrogens, butolame [17 beta-(4-hydroxy-1-butylamino)-1,3,5(10)-estratrien-3-ol] and pentolame [17 beta-(5-hydroxy-1-pentylamino)-1,3,5(10)-estratrien-3-ol], are presented. Both compounds, when administered in single subcutaneous injections to male mice and rats, produce dose-dependent increases in blood clotting times that may last several days. The estrogenic effects assessed by the vaginal cornification test are of relatively short duration.


Assuntos
Amino Álcoois/síntese química , Anticoagulantes/síntese química , Congêneres do Estradiol/síntese química , Estrenos/síntese química , Amino Álcoois/administração & dosagem , Amino Álcoois/farmacologia , Animais , Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Congêneres do Estradiol/farmacologia , Estrenos/administração & dosagem , Estrenos/farmacologia , Feminino , Cinética , Masculino , Camundongos , Ovariectomia , Ratos , Ratos Wistar , Vagina/efeitos dos fármacos , Vagina/fisiologia
7.
Obstet Gynecol ; 47(1): 21-7, 1976 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-813162

RESUMO

An experience with the lecithin/sphingomyelin (L/S) ratio in a population of high-risk obstetric patients is presented. A wide range of values in ralation to gestational age was found. A delayed rise in L/S ratio was found in Class A diabetes and Rh sensitization but was most striking in Class B through F diabetes. Chronic hypertension alone or in combination with diabetes is associated with an earlier rise in L/S ratio. A poor correlation of L/S ratio and neonatal pulmonary outcome with birthweight and gestational age was found. However, a good correlation between L/S ratio and neonatal pulmonary outcome was apparent. An L/S ratio of over 2 was universally associated with absence of serious RDS, but a low L/S ratio was less precisely predictive.


Assuntos
Líquido Amniótico/análise , Fosfatidilcolinas/análise , Complicações na Gravidez/diagnóstico , Esfingomielinas/análise , Peso ao Nascer , Diabetes Mellitus/diagnóstico , Feminino , Humanos , Hipertensão/diagnóstico , Recém-Nascido , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Hematológicas na Gravidez/diagnóstico , Gravidez em Diabéticas/diagnóstico , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Sistema do Grupo Sanguíneo Rh-Hr
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