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1.
Braz. j. med. biol. res ; 51(2): e6808, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889020

RESUMO

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Acromegalia/patologia , Adenoma/patologia , Caderinas/análise , Moléculas de Adesão de Célula Nervosa/análise , Fatores de Transcrição da Família Snail/análise , Acromegalia/genética , Acromegalia/metabolismo , Imuno-Histoquímica , Biomarcadores Tumorais/análise , Adenoma/genética , Adenoma/química , Expressão Gênica , Estudos Transversais , Gradação de Tumores
2.
Braz J Med Biol Res ; 51(2): e6808, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29267504

RESUMO

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.


Assuntos
Acromegalia/patologia , Adenoma/patologia , Caderinas/análise , Moléculas de Adesão de Célula Nervosa/análise , Neoplasias Hipofisárias/patologia , Fatores de Transcrição da Família Snail/análise , Acromegalia/genética , Acromegalia/metabolismo , Adenoma/química , Adenoma/genética , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/análise , Antígeno CD56/análise , Estudos Transversais , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Neoplasias Hipofisárias/química , Neoplasias Hipofisárias/genética , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não Paramétricas , Adulto Jovem
3.
Braz J Med Biol Res ; 49(4): e5125, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27007654

RESUMO

Meningiomas are common, usually benign tumors of the central nervous system that have a high rate of post-surgical recurrence or regrowth. We determined expression of the proteins merlin, NDRG2, ERBB2, and c-MYC in meningiomas using immunohistochemistry and assessed relationships between protein expression and gender, age, tumor grade, and recurrence or regrowth. The study sample comprised 60 patients, (44 women and 16 men) with a mean age of 53.2 ± 12.7 years. Tumors were classified as grade I (n=48) or grades II and III (n=12). Expression of merlin, NDRG2, ERBB2, and c-MYC was not significantly different statistically with relation to gender, age, or meningioma recurrence or regrowth. Merlin was expressed in 100% of the cases. No statistically significant difference between tumor grade and recurrence or regrowth was identified. Statistically significant differences were identified between the mean age of patients with grade I (54.83 ± 11.60) and grades II and III (46.58 ± 15.08) meningiomas (P=0.043), between strong c-MYC expression and grades II and III (P<0.001), and between partial surgical resection and tumor recurrence or regrowth (P<0.001). These findings reveal the lower mean age among grades II and III meningioma patients than grade I patients, the influence of the protein merlin on tumorigenesis, the association of c-MYC with aggressive meningiomas, and that partial surgical resection is associated with tumor recurrence or regrowth.


Assuntos
Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Neurofibromina 2/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptor ErbB-2/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Neoplasias Meníngeas/patologia , Meningioma/patologia , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia , Fatores de Tempo
4.
Braz. j. med. biol. res ; 49(4): e5125, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951662

RESUMO

Meningiomas are common, usually benign tumors of the central nervous system that have a high rate of post-surgical recurrence or regrowth. We determined expression of the proteins merlin, NDRG2, ERBB2, and c-MYC in meningiomas using immunohistochemistry and assessed relationships between protein expression and gender, age, tumor grade, and recurrence or regrowth. The study sample comprised 60 patients, (44 women and 16 men) with a mean age of 53.2±12.7 years. Tumors were classified as grade I (n=48) or grades II and III (n=12). Expression of merlin, NDRG2, ERBB2, and c-MYC was not significantly different statistically with relation to gender, age, or meningioma recurrence or regrowth. Merlin was expressed in 100% of the cases. No statistically significant difference between tumor grade and recurrence or regrowth was identified. Statistically significant differences were identified between the mean age of patients with grade I (54.83±11.60) and grades II and III (46.58±15.08) meningiomas (P=0.043), between strong c-MYC expression and grades II and III (P<0.001), and between partial surgical resection and tumor recurrence or regrowth (P<0.001). These findings reveal the lower mean age among grades II and III meningioma patients than grade I patients, the influence of the protein merlin on tumorigenesis, the association of c-MYC with aggressive meningiomas, and that partial surgical resection is associated with tumor recurrence or regrowth.


Assuntos
Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Receptor ErbB-2/metabolismo , Neurofibromina 2/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Fatores de Tempo , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Gradação de Tumores , Neoplasias Meníngeas/patologia , Meningioma/patologia , Recidiva Local de Neoplasia
5.
Mol Ecol ; 19(22): 4906-21, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21040050

RESUMO

Habitat fragmentation may disrupt original patterns of gene flow and lead to drift-induced differentiation among local population units. Top predators such as the jaguar may be particularly susceptible to this effect, given their low population densities, leading to small effective sizes in local fragments. On the other hand, the jaguar's high dispersal capabilities and relatively long generation time might counteract this process, slowing the effect of drift on local populations over the time frame of decades or centuries. In this study, we have addressed this issue by investigating the genetic structure of jaguars in a recently fragmented Atlantic Forest region, aiming to test whether loss of diversity and differentiation among local populations are detectable, and whether they can be attributed to the recent effect of drift. We used 13 microsatellite loci to characterize the genetic diversity present in four remnant populations, and observed marked differentiation among them, with evidence of recent allelic loss in local areas. Although some migrant and admixed individuals were identified, our results indicate that recent large-scale habitat removal and fragmentation among these areas has been sufficiently strong to promote differentiation induced by drift and loss of alleles at each site. Low estimated effective sizes supported the inference that genetic drift could have caused this effect within a short time frame. These results indicate that jaguars' ability to effectively disperse across the human-dominated landscapes that separate the fragments is currently very limited, and that each fragment contains a small, isolated population that is already suffering from the effects of genetic drift.


Assuntos
Ecossistema , Estruturas Genéticas , Genética Populacional , Panthera/genética , Árvores/genética , Animais , Brasil , Deriva Genética , Variação Genética , Humanos , Repetições de Microssatélites , Família Multigênica
6.
J Mal Vasc ; 24(4): 267-74, 1999 Oct.
Artigo em Francês | MEDLINE | ID: mdl-10582175

RESUMO

After a long period of neglect, pelvic vein pathology must be recognized today as a true pathological entity. It is easy to understand how fragile the veins are and how liable to poor venous return when the anatomical, histological and functional characteristics of the venous system of the pelvis are properly understood. Furthermore this pathology has an adverse effect on peripheral and underlying venous functions. Initially revealed by transuterine hysterophlebography, the morphological and functional disorders of the pelvic veins can now be shown by color Doppler ultrasonography, which is indeed the tool of first intention for diagnosis and therapeutic assessment, being capable of displaying the variations in calibre of the veins and more particularly of establishing their flow rates. Study of pelvic vascularization has two fundamental applications for gynecology: non specific chronic, pelvic pain which represents between 15 and 20% of reasons for patients consulting, and premenstrual syndrome dominated by congestive phenomena. The indispensable accompaniment to Doppler ultrasonography for investigation of persistent pelvic pain is laparoscopy, which confirms the venous dilatation involved, assesses any associated lesions also liable to slow venous flow and offers simple and efficient methods for treatment.


Assuntos
Pelve/irrigação sanguínea , Varizes/patologia , Varizes/terapia , Humanos , Ultrassonografia Doppler em Cores , Varizes/diagnóstico por imagem
7.
Dev Biol ; 208(1): 56-69, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10075841

RESUMO

Heart development in the Drosophila embryo starts with the specification of cardiac precursors from the dorsal edge of the mesoderm through signaling from the epidermis. Cardioblasts then become aligned in a single row of cells that migrate dorsally. After contacting their contralateral counterparts, cardioblasts undergo a cytoskeletal rearrangement and form a lumen. Its simple architecture and cellular composition makes the heart a good system to study mesodermal patterning, intergerm layer signaling, and the function of cell adhesion molecules (CAMs) during morphogenesis. In this paper we focus on three adhesion molecules, faint sausage (fas), shotgun/DE-cadherin (shg/DE-Cad), and laminin A (lam A), that are essential for heart development. fas encodes an Ig-like CAM and is required for the correct number of cardioblasts to become specified, as well as proper alignment of cardioblasts. shg/DE-Cad is expressed and required at a later stage than fas; in embryos lacking this gene, cardioblasts are specified normally and become aligned, but do not form a lumen. Additionally, cardioblasts of shg mutant embryos show a redistribution of phosphotyrosine as well as a loss of Armadillo from the membrane, indicating defects in cell polarity. The shg phenotype could be phenocopied by applying EGTA or cytochalasin D, supporting the view that Ca2+-dependent adhesion and the actin cytoskeleton are instrumental for heart lumen formation. As opposed to cell-cell adhesion, cell-substrate adhesion mechanisms are not required for heart morphogenesis, but only for maintenance of the differentiated heart. Embryos lacking the lam A gene initially developed a normal heart, but showed twists and breaks of cardioblasts at late embryonic stages. We discuss our findings in light of recent results that elucidate the function of different adhesion systems in vertebrate heart development.


Assuntos
Caderinas/genética , Proteínas de Drosophila , Drosophila/embriologia , Coração/embriologia , Laminina/genética , Neuropeptídeos/genética , Animais , Cálcio/farmacologia , Adesão Celular/genética , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento/genética , Imuno-Histoquímica , Mesoderma/metabolismo , Morfogênese , Fenótipo
8.
Mod Pathol ; 9(11): 1071-80, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8933518

RESUMO

TSC2 is a gene on chromosome 16p13.3 associated with the autosomal dominant neurocutaneous disorder, tuberous sclerosis complex (TSC). By using a partial nucleotide sequence from the cloned TSC2 and polymerase chain reaction methodology, we constructed a digoxigenin-labeled complementary DNA probe to examine TSC2 gene expression in autopsy- or biopsy-derived human tissues by in situ hybridization. TSC2 messenger RNA was widely expressed in various cell types throughout the body, including epithelia, lymphocytes, and cells with endocrine functions, e.g., adrenal cortex and anterior pituitary. It was prominently and selectively (within the central nervous system) expressed in pyramidal cells of the cerebral cortex and other motor neurons, e.g., in spinal cord and brainstem nuclei. Visceral TSC2 expression was comparable in autopsy tissues from patients with and without TSC; TSC2 messenger RNA expression was most prominent in cells with a rapid mitotic rate and turnover, e.g., epithelia and lymphocytes, with central nervous system pyramidal cells and other neurons being an obvious exception, and/or in cells with important secretory/transport functions. This widespread expression of the TSC2 gene supports the view that it encodes a protein vital to cell growth and metabolism or one that functions as a tumor/growth suppressor.


Assuntos
Encéfalo/metabolismo , Glândulas Endócrinas/metabolismo , Genes Supressores de Tumor/genética , Linfócitos/metabolismo , RNA Mensageiro/biossíntese , Proteínas Repressoras/biossíntese , Esclerose Tuberosa/metabolismo , Adulto , Encéfalo/patologia , Criança , Pré-Escolar , Primers do DNA/química , Sondas de DNA , Glândulas Endócrinas/patologia , Epitélio/metabolismo , Epitélio/patologia , Feminino , Expressão Gênica , Humanos , Hibridização In Situ , Lactente , Recém-Nascido , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Gravidez , Distribuição Tecidual , Esclerose Tuberosa/genética , Esclerose Tuberosa/patologia , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor
9.
Genes Dev ; 10(6): 672-85, 1996 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8598295

RESUMO

Adhesion molecules of the cadherin superfamily have an important role during vertebrate development. The DE-cadherin homolog DE-cadherin is the first classic cadherin isolated from invertebrates. We report here that DE-cadherin is encoded by the shotgun (shg) gene. shg is expressed in most embryonic epithelia and decreases in cells that undergo epithelial-mesenchymal transitions like the mesoderm or neural precursors. Removal of both maternal and zygotic shg function leads to severe defects in all epithelia expressing shg, suggesting that DE-cadherin, similar to vertebrate classic cadherins, has a crucial role for the formation and/or maintenance of epithelial tissues. Interestingly, the analysis of different shg alleles indicates that the requirement for shg in a given epithelium depends on the degree of its morphogenetic activity. Only epithelia involved in extensive morphogenetic movements require zygotic shg function in addition to maternal expression. In support of this view we find that suppression of morphogenetic movements rescues the zygotic shg phenotype. We find that in zygotic shg nulls the level of Dalpha-catenin and Armadillo at adherens junctions is dramatically reduced, surprisingly also in epithelia that differentiate normally and possess a zonula adherens.


Assuntos
Caderinas/genética , Drosophila/embriologia , Ectoderma/citologia , Desenvolvimento Embrionário , Genes de Insetos , Animais , Sequência de Bases , Caderinas/fisiologia , Clonagem Molecular , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Sondas de DNA , Drosophila/genética , Ectoderma/metabolismo , Embrião não Mamífero/metabolismo , Epitélio/embriologia , Epitélio/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Dados de Sequência Molecular , Morfogênese/genética , Mutação , Oogênese , Fenótipo , Zigoto/metabolismo , alfa Catenina
10.
Nat Struct Biol ; 1(8): 532-7, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7664081

RESUMO

The crystal structure of the bromoperoxidase A2 from Streptomyces aureofaciens (ATCC 10762) has been determined by isomorphous replacement and refined to 2.05 A resolution with an R-value of 18.4%. The enzyme catalyzes the bromination of organic compounds in the presence of bromide and peroxide. The structure confirms the absence of cofactors such as metal ions or haem groups and shows the general topology of the alpha/beta hydrolase fold. The active centre is at the end of a deep pocket and includes a catalytic triad of Ser 98, Asp 228 and His 257. The active centre is connected by a narrow tunnel to a second pocket on the enzyme surface.


Assuntos
Proteínas de Bactérias/química , Modelos Moleculares , Peroxidases/química , Conformação Proteica , Streptomyces aureofaciens/enzimologia , Sequência de Aminoácidos , Sítios de Ligação , Catálise , Cristalografia por Raios X , Hidrolases/química , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
11.
Gynecol Obstet Invest ; 37(3): 191-5, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8005551

RESUMO

Thirty-one patients complaining of unexplained infertility for at least 36 months and diagnosed elsewhere were reassessed laparoscopically. After staining their pelvic peritoneum with concentrated methylene blue, they presented with extensive areas of dark blue discoloration, and were diagnosed as suffering from 'diseased pelvic peritoneum'. The levels of peritoneal CA 125 were assessed. At the end of the diagnostic procedure, bipolar electrocoagulation or defocalized laser beam therapy was performed to destroy the affected peritoneal areas, and to allow peritoneal regeneration. Twenty-five pregnancies were obtained following this treatment. A detailed description is given of the diagnosis and treatment procedures.


Assuntos
Infertilidade Feminina/etiologia , Laparoscopia , Doenças Peritoneais/complicações , Adulto , Antígenos Glicosídicos Associados a Tumores/análise , Eletrocoagulação , Feminino , Humanos , Infertilidade Feminina/cirurgia , Terapia a Laser , Azul de Metileno , Doenças Peritoneais/diagnóstico , Doenças Peritoneais/cirurgia , Gravidez
12.
J Mol Biol ; 221(1): 35-7, 1991 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-1920414

RESUMO

Bromoperoxidase from Streptomyces aureofaciens ATCC 10762, a non-haem haloperoxidase, has been crystallized using the hanging drop method. Preliminary X-ray diffraction studies show that the crystals belong to the cubic space group P2(1)3 with a = 123.4 A. The asymmetric unit contains a dimer of Mr = 60,200. The crystals diffract to at least 2.3 A resolution and are suitable for crystallographic structure analysis.


Assuntos
Peroxidases/química , Streptomyces aureofaciens/enzimologia , Cristalização , Difração de Raios X
13.
AJR Am J Roentgenol ; 130(4): 715-8, 1978 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-416682

RESUMO

The occurrence of bacteremia was studied in patients undergoing barium enema. Blood cultures were done on 34 patients before, during, and after the procedure using two schedules. Cultures were obtained once during the procedure in the first schedule and four times in the second. None of the cultures were positive by the first schedule, while 23% of patients studied by the second schedule had one or more positive cultures. Organisms isolated were anaerobes. The bacteremia was transient and self-limited, without serious clinical sequelae. The incidence of bacteremia during barium enema examination was statistically indistinguishable from bacteremia previously reported during colonscopy. It is concluded that antibiotic prophylaxis is not indicated in most patients undergoing colonic diagnostic procedures. Prophylaxis in selected high-risk patients requires further study.


Assuntos
Sulfato de Bário , Enema/efeitos adversos , Sepse/etiologia , Adulto , Idoso , Sulfato de Bário/administração & dosagem , Meios de Contraste/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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