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1.
Anim Reprod Sci ; 250: 107210, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36913895

RESUMO

The objective of the present study was to evaluate the effect of GnRH dose administered at initiation (GnRH-1) of a 5-day CO-Synch + P4 protocol on ovulatory response, expression of estrus, and fertility in suckled beef cows. Suckled beef cows (n = 1101) at four locations were randomized to receive either 100 or 200 µg of gonadorelin acetate at initiation (D-8) of a 5-day CO-Synch + P4 protocol concurrently with insertion of an intravaginal progesterone (P4) device. On D-3 the P4 device was removed, two doses of prostaglandin F2α were administered concurrently and a patch was applied to evaluate expression of estrus. Artificial insemination was performed 72 h after P4 device removal (D0) simultaneously with the administration of 100 µg of gonadorelin acetate (GnRH-2). Increasing GnRH dose at initiation of a 5-day CO-Synch + P4 did not enhance ovulatory response (P = 0.57) to GnRH-1, expression of estrus (P = 0.79), nor pregnancies per AI (P/AI; P = 0.91). Both follicle size (quadratic) and circulating P4 (linear) affected (P < 0.01) ovulatory response to GnRH-1 independent of dose. Cows that had ovulation to GnRH-1 had smaller (P < 0.001) follicle size on D-3 and reduced (P = 0.05) expression of estrus compared to cows that did not have ovulation to GnRH-1, however, P/AI did not differ (P = 0.75). In conclusion, increasing the dose of GnRH-1 in the 5-day CO-Synch + P4 protocol did not enhance ovulatory response, expression of estrus, or P/AI in suckled beef cows.


Assuntos
Sincronização do Estro , Progesterona , Gravidez , Feminino , Bovinos , Animais , Sincronização do Estro/métodos , Progesterona/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Estro/fisiologia , Dinoprosta , Inseminação Artificial/veterinária , Inseminação Artificial/métodos
2.
Rev. argent. endocrinol. metab ; 51(4): 205-212, dic. 2014.
Artigo em Espanhol | LILACS | ID: lil-750592

RESUMO

El descubrimiento de los microRNAs (miRNAs) ha demostrado que estos se comportan como una poderosa clase de reguladores de la expresión génica. Al actuar a nivel postranscripcional, los miRNAs son capaces de modular la expresión de al menos un tercio de los RNA mensajeros codificados por el genoma. Aquí resumimos las principales alteraciones en la expresión de los genes para miRNAs identificados en el carcinoma papilar de tiroides. Se discuten también los mecanismos por los cuales la desregulación de estos miRNAs podrían estar involucrados en la transformación de las células foliculares tiroideas. Rev Argent Endocrinol Metab 51:205-212, 2014 Los autores declaran no poseer conflictos de interés.


MicroRNAs (miRNAs) small (~22 nt) single-stranded RNA molecules that are not further translated into proteins. They can act as negative regulators of the protein-coding gene expression and may impact cell differentiation, proliferation and survival. They have been implicated in carcinogenesis. The purpose of this review is to summarize the main alterations of miRNA expression identified in thyroid papillary carcinomas, and discuss the mechanisms by which miRNA deregulation might be involved in thyroid cell transformation. Rev Argent Endocrinol Metab 51:205-212, 2014 No financial conflicts of interest exist.

3.
Lung Cancer ; 79(3): 236-41, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23279873

RESUMO

BACKGROUND: The WHO-classification was shown to be an independent prognostic marker in some but not all retrospective studies possibly due to lack of reproducibility. We investigated the reproducibility of the WHO-classification and its prognostic implication using a large series of resected thymomas. METHODS: Four independent pathologists histologically classified a surgical series of 129 thymic tumors in a blinded fashion. Fleiss' kappa-coefficient was used to assess the pathologists' overall agreement, and Cohen-Kappa to assess the agreement between two observers. Disease-related-survival (DRS) and progression-free-survival (PFS) curves were generated by Kaplan-Meier method and compared by log-rank test. RESULTS: In 63/129 (48.8%) cases there was a complete agreement; in 43/129 (33.3%) cases 3/4 pathological diagnoses were identical; in 15/129 (11.6%) cases the diagnoses were identical by pair; in 8/129 (6.2%) cases three different pathological diagnoses were on record. The Kappa-correlation coefficient was only moderate (0.53). A following web review carried out on the 23 cases with at least two different diagnoses reached a complete consensus. The histotype showed a statistically significant impact on PFS and DRS in the classification provided by only two pathologists. CONCLUSIONS: In this study, the agreement on WHO classification of thymomas was only moderate and this impacted on patients management. Web consensus conference on the diagnosis, more stringent diagnostic criteria or the adoption of referral diagnostic centres may substantially reduce discrepancies.


Assuntos
Timoma/classificação , Timoma/patologia , Organização Mundial da Saúde , Adulto , Idoso , Idoso de 80 Anos ou mais , Consenso , Conferências de Consenso como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Guias de Prática Clínica como Assunto , Prognóstico , Reprodutibilidade dos Testes , Timoma/mortalidade , Adulto Jovem
4.
Am J Transplant ; 8(3): 673-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18294164

RESUMO

Hepatitis C virus (HCV) re-infection after liver transplantation (LT) is characterized by an accelerated disease progression in recent years with unclear mechanisms. We evaluate the relationship between progression of liver fibrosis and histological necro-inflammation in HCV recipients, according to age of transplant. Fifty-five patients transplanted (1993-2002) for HCV liver disease, were included in the study. Recipients were retrospectively stratified in three different age of transplant, of 40 months each: group 1) from January 1993 to May 1996; group 2) from June 1996 to august 1999; group 3) from September 1999 to December 2002. Grading (necro-inflammation) and staging (fibrosis) scores were evaluated in liver biopsies at 1, 2 and 3 years from LT (Ishak classification). For all age of transplant the main factor associated with fibrosis progression, was grading score (p < 0.05). However mean staging score for each point of grading increased from 0.3 +/- 0.2 in older LT to 0.7 +/- 0.5 in newer ones (p = 0.01). In conclusion in HCV-LT patients (1) liver fibrosis is strictly associated to histological necro-inflammation; (2) the proportion of this relationship has been changing in recent years since newer LT patients, show an increased amount of fibrosis in comparison with the older ones, for similar grading score.


Assuntos
Hepatite C Crônica/patologia , Hepatite C Crônica/cirurgia , Cirrose Hepática/patologia , Cirrose Hepática/cirurgia , Transplante de Fígado , Fatores Etários , Progressão da Doença , Feminino , Hepacivirus/isolamento & purificação , Hepatite C Crônica/complicações , Humanos , Terapia de Imunossupressão , Inflamação/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Recidiva
5.
Biomaterials ; 28(20): 3101-9, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17412415

RESUMO

The ability of a cellular construct to guide and promote tissue repair strongly relies on three components, namely, cell, scaffold and growth factors. We aimed to investigate the osteopromotive properties of cellular constructs composed of poly-epsilon-caprolactone (PCL) and rabbit bone marrow stromal cells (BMSCs), or BMSCs engineered to express bone morphogenetic protein 4 (BMP4). Highly porous biodegradable PCL scaffolds were obtained via phase inversion/salt leaching technique. BMSCs and transfected BMSCs were seeded within the scaffolds by using an alternate flow perfusion system and implanted into non-critical size defects in New Zealand rabbit femurs. In vivo biocompatibility, osteogenic and angiogenic effects induced by the presence of scaffolds were assessed by histology and histomorphometry of the femurs, retrieved 4 and 8 weeks after surgery. PCL without cells showed scarce bone formation at the scaffold-bone interface (29% bone/implant contact and 62% fibrous tissue/implant contact) and scarce PCL resorption (16%). Conversely, PCL seeded with autologous BMSCs stimulated new tissue formation into the macropores of the implant (20%) and neo-tissue vascularization. Finally, the BMP4-expressing BMSCs strongly favoured osteoinductivity of cellular constructs, as demonstrated by a more extensive bone/scaffold contact.


Assuntos
Materiais Biocompatíveis/química , Células da Medula Óssea/citologia , Proteínas Morfogenéticas Ósseas/metabolismo , Caproatos/química , Fêmur/cirurgia , Lactonas/química , Células Estromais/citologia , Animais , Materiais Biocompatíveis/metabolismo , Células da Medula Óssea/metabolismo , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/genética , Transplante de Células/métodos , Fêmur/crescimento & desenvolvimento , Fêmur/metabolismo , Vetores Genéticos/genética , Osteogênese , Polímeros/química , Coelhos , Células Estromais/metabolismo , Células Estromais/transplante , Fatores de Tempo , Engenharia Tecidual/métodos , Transfecção , Transplante Autólogo
6.
J Mater Sci Mater Med ; 18(2): 245-53, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17323155

RESUMO

Recent studies, on cells cultured in 3D collagen gels, have shown that, beside from their well known biochemical role, fibronectin (FN) and laminin (LM) affect cell functions via a modification of mechanical and structural properties of matrix due to interaction with collagen molecules. Though biochemical properties of FN and LM have been widely studied, little is known about their role in collagen matrix assembly. The aim of this work was to characterize FN- and LM-based collagen semi-interpenetrating polymer networks (semi-IPNs), in order to understand how these biomacromolecular species can affect collagen network assembly and properties. Morphology, viscoelasticity and diffusivity of collagen gels and FN- and LM-based collagen semi-IPNs were analysed by Confocal Laser Scanning microscopy (CLSM), Environmental Scanning Electron microscopy (ESEM), Transmission Electron microscopy (TEM), Rheometry and Fluorescence Recovery After Photobleaching (FRAP) techniques. It was found that FN and LM were organized in aggregates, interspersed in collagen gel, and in thin fibrils, distributed along collagen fibres. In addition, high FN and LM concentrations affected collagen fibre assembly and structure and induced drastic effects on rheological and transport properties.


Assuntos
Materiais Biocompatíveis/química , Colágeno Tipo I/química , Fibronectinas/química , Fibronectinas/ultraestrutura , Laminina/química , Laminina/ultraestrutura , Engenharia Tecidual/métodos , Absorção , Materiais Biomiméticos/química , Técnicas de Cultura de Células/métodos , Colágeno Tipo I/ultraestrutura , Cristalização/métodos , Difusão , Elasticidade , Matriz Extracelular/química , Teste de Materiais , Mecânica , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Viscosidade , Água/química
7.
Acta gastroenterol. latinoam ; 35(3): 162-164, set. 2005. ilus
Artigo em Espanhol | LILACS | ID: lil-443574

RESUMO

BACKGROUND: The most common type of gallbladder cancer is the adenocarcinoma. The squamous cell carcinoma represents only a 0-12% of all gallbladder tumors. METHODS: 124 cases of malignant neoplasias of the gallbladder were diagnosed during the last 33 years in the Department of Surgery of our hospital. From these cases, 5 were squamous cell carcinomas, representing 2.41% of our series. CASE REPORT: The ratio female: male was 1.5:1, and the mean age was 50.2 years. Liver involvement was observed in 4 of 5 patients at the moment of diagnosis. Four patients underwent surgery and one received palliative treatment with percutaneous bile dreinage. The mean survival was 14.5 months. CONCLUSION: The tumor extention at the time of diagnosis is generally advanced and the outcome is not promising in this kind of gallbladder cancer.


Antecedentes: El tumor maligno de vesícula más frecuente es el adenocarcinoma. El carcinoma epidermoide representa solamente el 0-12% de todos ellos. Métodos: Se analizaron retrospectivamente 124 casos de neoplasias malignas de vesícula biliar diagnosticadosen los últimos 33 años en nuestro Servicio de Cirugía. Cinco resultaron ser carcinomas epidermoides,lo que representa un 2.41%. Casos: La relación mujer: varón fue de 1.5:1, y la edad media de presentación, 50.2 años. El compromiso hepático se observó en4 de los 5 pacientes en el momento del diagnóstico. Cuatro pacientes fueron sometidos a cirugía y un pacientea tratamiento paliativo con drenaje biliar percutáneo. La sobrevida media fue de 14.5 meses. Conclusión: La extensión tumoral en el momento deldiagnóstico es, en general, avanzada, por lo que el pronóstico en esta estirpe de cáncer de vesícula no es promisorio.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Carcinoma de Células Escamosas , Neoplasias da Vesícula Biliar , Argentina , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/terapia , Distribuição por Sexo , Estudos Retrospectivos , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/terapia
8.
Acta gastroenterol. latinoam ; 35(3): 162-164, set. 2005. ilus
Artigo em Espanhol | BINACIS | ID: bin-123318

RESUMO

BACKGROUND: The most common type of gallbladder cancer is the adenocarcinoma. The squamous cell carcinoma represents only a 0-12% of all gallbladder tumors. METHODS: 124 cases of malignant neoplasias of the gallbladder were diagnosed during the last 33 years in the Department of Surgery of our hospital. From these cases, 5 were squamous cell carcinomas, representing 2.41% of our series. CASE REPORT: The ratio female: male was 1.5:1, and the mean age was 50.2 years. Liver involvement was observed in 4 of 5 patients at the moment of diagnosis. Four patients underwent surgery and one received palliative treatment with percutaneous bile dreinage. The mean survival was 14.5 months. CONCLUSION: The tumor extention at the time of diagnosis is generally advanced and the outcome is not promising in this kind of gallbladder cancer.(AU)


Antecedentes: El tumor maligno de vesícula más frecuente es el adenocarcinoma. El carcinoma epidermoide representa solamente el 0-12% de todos ellos. Métodos: Se analizaron retrospectivamente 124 casos de neoplasias malignas de vesícula biliar diagnosticadosen los últimos 33 años en nuestro Servicio de Cirugía. Cinco resultaron ser carcinomas epidermoides,lo que representa un 2.41%. Casos: La relación mujer: varón fue de 1.5:1, y la edad media de presentación, 50.2 años. El compromiso hepático se observó en4 de los 5 pacientes en el momento del diagnóstico. Cuatro pacientes fueron sometidos a cirugía y un pacientea tratamiento paliativo con drenaje biliar percutáneo. La sobrevida media fue de 14.5 meses. Conclusión: La extensión tumoral en el momento deldiagnóstico es, en general, avanzada, por lo que el pronóstico en esta estirpe de cáncer de vesícula no es promisorio.(AU)


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas , Neoplasias da Vesícula Biliar , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/terapia , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/terapia , Estudos Retrospectivos , Distribuição por Sexo , Argentina
11.
Minerva Gastroenterol Dietol ; 48(4): 309-18, 2002 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-16491056

RESUMO

The L-arginine/nitric oxide (NO) pathway has been recognized as a main regulator of several cell functions. Accordingly, there is an increasing number of pathophysiological conditions in which a precise knowledge of NO status could prove helpful in understanding the mechanisms involved in disease development, prevention and treatment. These include several hepatic disorders, such as liver cirrhosis and associated hyperdynamic circulation with portal hypertension, ischaemia-reperfusion injury occurring during liver transplantation, and chronic cholestatic conditions. Overall, NO seems to exert a dual role in the pathobiology of liver diseases: one mostly beneficial, due to its vasoactive effects; and one mostly negative, due to its local toxic effects. Protective actions are primarily mediated via vasodilation, antithrombosis, inhibition of neutrophil adhesion and inhibition of apoptosis. Deleterious effects are dependent upon the formation of highly reactive substances during oxidative stress. In this review aspects related to NO implications in the homeostasis of liver functions as well as in the pathogenesis of some relevant hepatic clinical syndromes will be discussed in view of possible therapeutic options.

12.
Carcinogenesis ; 22(10): 1583-91, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11576996

RESUMO

The HMGA family is comprised of four proteins: HMGA1a, HMGA1b, HMGA1c and HMGA2. The first three proteins are products of the same gene, HMGA1, generated through an alternative splicing mechanism. The HMGA proteins are involved in the regulation of chromatin structure and HMGA DNA-binding sites have been identified in functional regions of many gene promoters. Rearrangements of the HMGA2 gene have been frequently detected in human benign tumors of mesenchymal origin including lipomas. 12q13-15 chromosomal translocations involving the HMGA2 gene locus, account for these rearrangements. The HMGA proteins have three AT-hook domains and an acidic C-terminal tail. The HMGA2 modifications consist in the loss of the C-terminal tail and fusion with ectopic sequences. A pivotal role of the HMGA2 rearrangements in the process of lipomagenesis is suggested by experiments showing that transgenic mice carrying a truncated HMGA2 gene showed a giant phenotype together with abdominal/pelvic lipomatosis. As HMGA2 null mice showed a great reduction in fat tissue, a positive role of the HMGA2 gene in adipocytic cell proliferation is proposed. More recently, similar alterations of the HMGA1 gene have been described. As the block of the HMGA1 protein synthesis induces an increase in growth rate of the pre-adipocytic cell line 3T3-L1, we suggest a negative role of the HMGA1 proteins in adipocytic cell growth and, therefore, we propose that adipocytic cell growth derives from the balance of the HMGA1 and HMGA2 protein functions.


Assuntos
Proteínas de Grupo de Alta Mobilidade/fisiologia , Lipoma/metabolismo , Proteínas de Plantas , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Animais , Humanos , Camundongos , Camundongos Transgênicos
13.
Cancer Res ; 61(11): 4583-90, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11389094

RESUMO

The high mobility group (HMG) proteins (HMGA1a, HMGA1b, and HMGA2) bind to DNA and interact with various transcriptional factors. Therefore, they play an important role in chromatin organization. HMGA protein expression is low in normal adult tissues, but abundant during embryonic development and in several experimental and human tumors. Blockage of HMGA expression inhibits the transformation of rat thyroid PC Cl 3 cells treated with oncogene-carrying retroviruses, thus implicating HMGA in rat thyroid transformation. To better understand the role of HMGA and to establish whether its up-regulated expression is sufficient to induce the transformed phenotype, we generated PC Cl 3 cells that overexpress the protein. We demonstrate that HMGA1b protein overexpression does not transform normal rat thyroid PC Cl 3 cells, but it deregulates their cell cycle: cells enter S-phase earlier and the G(2)-M transition is delayed. HMGA1-overexpressing cells undergo apoptosis through a pathway involving caspase-3 activation, probably consequent to the conflict between mitogenic pressure and the inability to proceed through the cell cycle. Using various HMGA1b gene mutations, we found that the third AT-hook domain and the acetylation site K60 are the protein regions required for induction of apoptosis in PC Cl 3 cells. In conclusion, although HMGA1 protein overexpression is associated with the malignant phenotype of rat and human thyroid cells, it does not transform normal thyroid cells in culture but leads them to programmed cell death.


Assuntos
Apoptose/fisiologia , Proteínas de Grupo de Alta Mobilidade/biossíntese , Glândula Tireoide/citologia , Glândula Tireoide/metabolismo , Animais , Proteína Quinase CDC2/metabolismo , Ciclo Celular/fisiologia , Divisão Celular/fisiologia , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Ciclinas/biossíntese , DNA Complementar/genética , Expressão Gênica , Proteínas de Grupo de Alta Mobilidade/genética , Mapeamento de Peptídeos , Isoformas de Proteínas , Ratos , Transfecção
14.
Proc Natl Acad Sci U S A ; 98(14): 7970-5, 2001 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-11427729

RESUMO

Rearrangements of the high mobility group protein I-C (HMGI-C) gene, consisting in the loss of the carboxyl-terminal tail, have been frequently detected in benign human tumors of mesenchymal origin. We have previously demonstrated that transgenic (TG) mice carrying a truncated HMGI-C construct (HMGI-C/T) exhibit a giant phenotype together with a predominantly abdominal/pelvic lipomatosis. Here, we report that HMGI-C/T TG mice develop natural killer (NK)-T/NK cell lymphomas starting from 12 months of age. We found an increased expression of IL-2 and IL-15 proteins and their receptors in these lymphomas, and we demonstrate that HMGI-C/T protein positively regulates their expression in vitro. Therefore, the HMGI-C/T-mediated chronic stimulation of the IL-2/IL-15 pathway could be responsible for the onset of NK-T/NK cell lymphomas in HMGI-C/T TG mice.


Assuntos
Proteínas de Grupo de Alta Mobilidade/genética , Interleucina-15/imunologia , Interleucina-2/imunologia , Linfoma de Células T/genética , Linfoma de Células T/imunologia , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/imunologia , Predisposição Genética para Doença , Proteínas de Grupo de Alta Mobilidade/imunologia , Humanos , Células Matadoras Naturais/patologia , Linfoma de Células T/etiologia , Linfoma de Células T/patologia , Camundongos , Camundongos Transgênicos
15.
Minerva Pediatr ; 53(1): 23-8, 2001 Feb.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-11309539

RESUMO

The microdeletion 4p16 has been found in two rare syndromes. Until now they were considered as two different syndromes: the Wolf-Hirschhorn syndrome (WHS) and the Pitt-Rogers-Danks (PRDS) syndrome characterized by a growth retardation before and after birth, microcrania, seizures, characteristic face with thin mouth, maxillary hypoplasia, short and large philtrum, characteristic nose and mental retardation. A case with 4p-16 microdeletion with phenotype characteristics similar to PRDS is reported. The patients described as PRDS are sometimes less seriously affected than patients with WHS. In fact, cases of death are not indicated in the first year of life, internal malformations are less frequent and the face lacks the typical Greek warrior helmet Recent studies have shown that WSS and PRDS are due to the absence of similar if not identical genetic segments and the clinical differences observed could be the outcome of an allele variation on the remaining homologous part.


Assuntos
Anormalidades Múltiplas/genética , Aberrações Cromossômicas , Deleção Cromossômica , Transtornos Cromossômicos , Cromossomos Humanos Par 4 , Anormalidades Craniofaciais/genética , Transtornos do Crescimento/genética , Humanos , Recém-Nascido , Masculino , Microcefalia/genética , Fenótipo , Síndrome
16.
Mol Cell Biol ; 21(7): 2485-95, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11259597

RESUMO

The high-mobility group I (HMGI) nonhistone chromosomal proteins HMGI(Y) and HMGI-C have been implicated in defining chromatin structure and in regulating the transcription of several genes. These proteins have been implicated in adipocyte homeostasis: a severe deficiency of fat tissue is found in mice with targeted disruption of the HMGI-C locus, and lipomagenesis in humans is frequently associated with somatic mutations of HMGI genes. The aim of this study was to examine the role of HMGI(Y) proteins in adipocytic cell growth and differentiation. First, we found that differentiation of the preadipocytic 3T3-L1 cell line caused early induction of HMGI(Y) gene expression. Suppression of HMGI(Y) expression by antisense technology dramatically increased the growth rate and impaired adipocytic differentiation in these cells. The process of adipogenic differentiation involves the interplay of several transcription factors, among which is the CCAAT/enhancer-binding protein (C/EBP) family of proteins. These factors are required for the transcriptional activation of adipocyte-specific genes. We also tested the hypothesis that HMGI(Y) might participate in transcriptional control of adipocyte-specific promoters. We found that HMGI(Y) proteins bind C/EBPbeta in vivo and in vitro. Furthermore, we show that HMGI(Y) strongly potentiates the capacity of C/EBPbeta to transactivate the leptin promoter, an adipose-specific promoter. Taken together, these results indicate that the HMGI(Y) proteins play a critical role in adipocytic cell growth and differentiation.


Assuntos
Adipócitos/citologia , Adipócitos/fisiologia , Proteínas de Grupo de Alta Mobilidade/fisiologia , Fatores de Transcrição/fisiologia , Células 3T3 , Animais , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Proteína HMGA1a , Camundongos
17.
Am J Gastroenterol ; 96(3): 869-75, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11280567

RESUMO

OBJECTIVE: Although possible implications of nitric oxide in the pathophysiology of liver cirrhosis have been extensively studied, until now few articles have addressed the assessment of nitric oxide production in primary biliary cirrhosis. This study was directed to evaluate circulating nitrosyl-hemoglobin levels as well as neutrophil elastase and soluble adhesion molecule concentrations in this condition, by assuming these parameters as possible markers of either inflammatory response or neutrophil activation. METHODS: Laboratory investigations were performed in 30 patients with primary biliary cirrhosis, in 13 patients with postviral and/or alcoholic cirrhosis, and in a group of eight subjects with chronic hepatitis. RESULTS: Although no difference was detected with respect to chronic hepatitis subjects, higher levels of nitrosyl-hemoglobin adducts were found in primary biliary cirrhosis patients than in postviral or alcoholic cirrhotics and in normal subjects (3.55+/-1.75 arbitrary units vs 1.95+/-0.57 and 0.84+/-0.34, p = 0.0004 and p < 0.0001, respectively). Similarly, more elevated concentrations of neutrophil elastase (213.7+/-192.0 microg/L vs 51.1+/-34.3 and 38.0+/-11.5, p < 0.0001 and p < 0.0001, respectively) as well as of soluble forms of intercellular adhesion molecule 1 and endothelial-leukocyte adhesion molecule 1 were shown in primary biliary cirrhosis patients than in subjects with cirrhosis of other etiologies and in controls. CONCLUSIONS: Highly enhanced nitric oxide production in primary biliary cirrhosis could be related to the development of strong inflammation and at least partially to neutrophil activation, thus suggesting a putative role of these cellular mediators in the development of liver damage owing to their ability to synthesize and release a wide variety of important factors, including elastase and nitric oxide.


Assuntos
Cirrose Hepática Biliar/metabolismo , Óxido Nítrico/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Selectina E/sangue , Feminino , Humanos , Molécula 1 de Adesão Intercelular/sangue , Elastase de Leucócito/sangue , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Cirrose Hepática Alcoólica/metabolismo , Masculino , Pessoa de Meia-Idade , Solubilidade , Viroses/complicações
18.
J Bone Miner Res ; 15(12): 2458-66, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11127210

RESUMO

Ultrasound (US) waves are mechanical vibrations that are applied to a material--bone tissue--in order to study its properties, that is, density, elasticity, and structure. In this study we evaluated in which way density and elasticity of the spongy bone influenced the transmission of 1.25 MHz US pulses. Twelve cylindrical specimens (diameter, 8 mm; height, 5 mm) excised from phalanxes of pig were decalcified with 0.5 M EDTA for different times (0, 2, and 5 days). During these periods, the samples underwent the following investigations: US transmission, density, and elasticity measurements. To assess the homogeneity of decalcification, the cross-sections of some samples were microradiographed. A detailed analysis of the US signal received was performed using velocity, Fourier analysis, and some parameters typical of signal processing technique. A good correlation was found between US velocity and density (r2 = 0.70); a lower correlation was found between velocity and elasticity (r2 = 0.59). If density and elasticity are considered simultaneously, the correlation with the US velocity improves significantly (r2 = 0.84). Fourier analysis enabled us to observe a shift of the main frequency toward lower values as the decalcification process advanced. We also observed that in the regressions weighted for density, US velocity correlated poorly with elasticity (r2 = 0.16), whereas signal processing parameters maintain a good correlation with elasticity (ultrasound peak amplitude [UPA], r2 = 0.48; slope, r2 = 0.62). In this study, it has been observed that when using a signal processing technique to analyze US pulses, it is possible to identify some parameters that are related in different ways to density and to elastic properties of bone. Our results show the potentiality of US technique to separate information on bone density and elasticity that X-ray-based densitometric methods do not provide.


Assuntos
Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/fisiologia , Animais , Técnica de Descalcificação , Elasticidade , Epífises/diagnóstico por imagem , Epífises/fisiologia , Membro Anterior/diagnóstico por imagem , Membro Anterior/fisiologia , Técnicas In Vitro , Processamento de Sinais Assistido por Computador , Suínos , Ultrassonografia
19.
Clin Cancer Res ; 6(11): 4300-6, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11106247

RESUMO

fra-1 gene overexpression has been shown to represent a general event in thyroid cell transformation in vitro and in vivo. Moreover, inhibition of FRA-1 protein synthesis by stable transfection with a fra-1 antisense construct significantly reduces the malignant phenotype of the transformed thyroid cells, indicating a pivotal role of the fra-1 gene product in the process of cellular transformation. In the attempt to define the potential use of FRA-1 protein detection in the diagnosis of thyroid diseases, we analyzed Fra-1 expression by a combination of immunohistochemistry and reverse transcription-PCR (RT-PCR) assay in 174 samples of thyroid nodules (22 nodular hyperplasias, 102 follicular adenomas, 34 papillary carcinomas, 12 follicular carcinomas, and 4 anaplastic carcinomas) representative of the spectrum of thyroid tumor pathology. FRA-1 protein was abundant in all of the carcinoma samples (50/50, 100%), with an intense staining in the nucleus and the cytoplasm. Positive staining was also found in most of the adenomas (90 of 102; 88%), but in this case, the staining was restricted to the nucleus. Similar results were obtained from the analysis of thyroid goiters; however, the number of positive cases is lower than adenomas (8 of 22; 36%); moreover, the staining was not observed in all of the cells. Conversely, no FRA-1 protein was detectable in 12 normal thyroid tissue samples used as controls. RT-PCR analysis confirmed a higher fra-1 expression in papillary and follicular carcinomas compared with goiters and adenomas. fra-1 expression was also analyzed on 10 fine needle aspiration biopsy (FNAB) samples by RT-PCR. fra-1-specific mRNA was detected in seven of the eight FNABs corresponding to thyroid nodules that were eventually diagnosed as adenomas (three of four) and carcinomas (four of four) after surgery. Conversely, no fra-1 gene expression was observed in two FNABs derived from normal thyroid. Further studies are required before suggesting FRA-1 protein detection as a useful tool for the diagnosis of hyperplastic and neoplastic disorders of the thyroid gland.


Assuntos
Proteínas Proto-Oncogênicas c-fos/análise , Proteínas Proto-Oncogênicas c-fos/genética , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo , Nódulo da Glândula Tireoide/metabolismo , Biópsia por Agulha , Proteína HMGA1a , Proteínas de Grupo de Alta Mobilidade/análise , Proteínas de Grupo de Alta Mobilidade/genética , Humanos , Hiperplasia , Imuno-Histoquímica , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Fatores de Transcrição/análise , Fatores de Transcrição/genética , Células Tumorais Cultivadas
20.
Eur J Intern Med ; 11(5): 283-285, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11025254

RESUMO

Primary neoplasms of the diaphragm are extremely rare and their diagnosis is often difficult. We present a case of leiomyosarcoma of the diaphragm in a 23-year-old male presenting with aspecific abdominal discomfort. The final diagnosis was achieved on the basis of histopathological findings after surgery. The role of different imaging techniques as diagnostic tools is also discussed.

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