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1.
J Fish Biol ; 82(4): 1259-68, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23557304

RESUMO

Hemiodus iratapuru, a new species of the Hemiodontidae from the Rio Iratapuru, a left bank tributary of the Rio Jari, Amazon Basin, Brazil, is described. The new species is diagnosed from other species of Hemiodus by modifications in the ectopterygoid, tooth form, scale counts, dorsal-fin form and colour pattern. The new species is proposed to be related to the Hemiodus quadrimaculatus species group.


Assuntos
Caraciformes/anatomia & histologia , Caraciformes/classificação , Animais , Brasil , Rios
2.
J Fish Biol ; 76(7): 1815-24, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20557633

RESUMO

The rediscovery of the enigmatic subterranean characiform Stygichthys typhlops is reported almost a half-century after the collection of the holotype, the only specimen previously known. Thirty-four specimens were collected in two shallow hand-dug wells at the region of the type locality, c. 13 km south-west of the town of Jaíba, Minas Gerais, Brazil. These specimens provide new information on the morphology of this species, and for the first time on its life history. The conservation status of S. typhlops is discussed. The species is severely threatened by habitat loss caused by exploitation of the aquifer.


Assuntos
Peixes/classificação , Animais , Brasil , Conservação dos Recursos Naturais , Ecossistema , Peixes/anatomia & histologia , Peixes/fisiologia
3.
J Fish Biol ; 75(10): 2615-28, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20738511

RESUMO

A new species of Moenkhausia is described from Rio Xingu and Rio Tapajós basins, Brazil. The new species is distinguished from its congeners, except from Moenkhausia moisae, by having more scales in the lateral series, 43-47 (v. 23-41 in the remaining congeners). The new species is distinguished from M. moisae by its colour pattern, which consists of a dark midlateral stripe, and an asymmetrical caudal blotch (inconspicuous or faded in specimens from the Rio Arinos) continuous with the midlateral stripe (v. narrow dark midlateral line and conspicuous, regularly rounded and symmetrical blotch not continuous with the midlateral line). The new species is putatively assumed to be mimetic to Jupiaba apenima, in the Rio Xingu and Rio Teles Pires drainages, and to Jupiaba yarina in the Rio Arinos. The two species of Jupiaba are sympatric and remarkably similar in size, general external morphology and colouration to the new species. A small difference occurs in the colouration between the two species of Jupiaba and is also observed in the two respectively sympatric morphotypes of the new species of Moenkhausia. The occurrence of polymorphic Batesian mimicry is therefore discussed for neotropical freshwater fishes.


Assuntos
Peixes/anatomia & histologia , Peixes/classificação , Animais , Brasil , Rios
4.
Dentomaxillofac Radiol ; 35(3): 213-6, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16618858

RESUMO

Actinomycosis of the paranasal sinuses is a rare occurrence and its clinical presentation does not suggest a specific diagnosis. Therefore, actinomycosis should be included in the differential diagnosis of neoplasms and granulomatous lesions of the head and neck region. However, the differentiation from a malignant neoplasm is not easy because the radiological findings are frequently similar and positive cultures are difficult to obtain. This report highlights the clinical progress of paranasal actinomycosis associated with some computed tomography findings that can be extremely helpful in the correct diagnosis. The characteristics of the disease are described and the relevant literature is discussed.


Assuntos
Actinomicose Cervicofacial/diagnóstico por imagem , Sinusite Maxilar/diagnóstico por imagem , Sinusite Maxilar/microbiologia , Idoso , Doença Crônica , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias do Seio Maxilar/diagnóstico , Tomografia Computadorizada por Raios X
5.
Melanoma Res ; 13(1): 11-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12569279

RESUMO

Dissemination of a malignant tumour is the result of a cascade of events beginning with detachment of cells from primary tumour followed by extravasation and growth at secondary sites. The differences in metastatic ability could be attributed to properties intrinsic to the various tumour types. Thus the clonal selection of tumour cells from successive metastases apparently results in cells better equipped for survival and formation of colonies in secondary sites, indicating that survival is not a random phenomenon. Many studies of malignant cells have correlated the overexpression of adhesion receptors such as integrins and the production of cysteine proteases and glycosidases with the progression of malignancy. The interaction of cysteine proteases with basement membrane components has been implicated in tumour invasion, activation of hormones and growth factors. On the other hand, the expression of the heparanase gene and its protein has been associated with the metastatic potential of several human and mouse tumour cell lines. This study aimed to investigate the correlations between the metastatic properties of clones with high and low metastatic potential and their ability to adhere to the extracellular matrix and to degrade proteins and sulphated glycosaminoglycans present there. Clonal selection of the B16F10 cell line was performed, and the clones were examined for the expression of an integrin-type laminin receptor. A significantly higher level was detected in a high metastatic clone. Enzymatic assays showed higher activity for alpha-d-N-acetylglucosaminidase, beta-d-N-acetylgalactosaminidase and beta-d-glucuronidase in conditioned medium from low metastatic clones compared with that from high metastatic clones. However, higher endopeptidase activity was observed in conditioned medium from high metastatic clones. In summary, these results showed a positive correlation between high metastatic potential and endopeptidase secretion. Similarly, a positive correlation was observed between low metastatic cells and the secretion of glycosaminoglycan-degrading glycosidases.


Assuntos
Acetilglucosaminidase/metabolismo , Endopeptidases/metabolismo , Glucuronidase/metabolismo , Hexosaminidases/metabolismo , Integrinas/metabolismo , Melanoma Experimental/enzimologia , Animais , Endotélio Vascular/enzimologia , Matriz Extracelular/metabolismo , Feminino , Citometria de Fluxo , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Coelhos , Taxa de Sobrevida , Células Tumorais Cultivadas
6.
J Cell Biochem ; 70(4): 563-72, 1998 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9712153

RESUMO

Fetal calf serum (FCS) and PMA (phorbol 12-myristate-13-acetate) specifically stimulate the synthesis of heparan sulfate proteoglycan in endothelial cells. Staurosporine and n-butanol, kinase inhibitors, abolish the PMA effect. Forskolin and 8-bromo adenosine 3':5'-cyclic monophosphate, activators of, respectively, adenylate cyclase and protein kinase A cannot reproduce the PMA effect. The kinetics of cell entry into S phase of the endothelial cells was determined by DNA synthesis ([3H]-thymidine and Br-dU incorporation), and flow cytometry. The mitogenic effect of fetal calf serum is abolished by PMA. Also, PMA pre-treatment inhibits the enhanced synthesis of heparan sulfate proteoglycan after a second PMA exposure. Remarkably, the stimulation of heparan sulfate proteoglycan synthesis by fetal calf serum and PMA seems to be mainly restricted to G1 phase. Therefore fetal calf serum and PMA cause an enhanced synthesis of heparan sulfate proteoglycan, and PMA causes a cell cycle block at G1 phase.


Assuntos
Fase G1 , Substâncias de Crescimento/farmacologia , Proteoglicanas de Heparan Sulfato/biossíntese , Acetato de Tetradecanoilforbol/farmacologia , Animais , Células Cultivadas , Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Endotélio Vascular/metabolismo , Ativação Enzimática , Citometria de Fluxo , Proteoglicanas de Heparan Sulfato/metabolismo , Proteína Quinase C/metabolismo , Coelhos
7.
Arq Gastroenterol ; 34(4): 262-9, 1997.
Artigo em Português | MEDLINE | ID: mdl-9629323

RESUMO

Three hundred and eleven hospitalized weaned infants with acute diarrhea, all under 12 months of age, were studied in order to evaluate the development of lactose intolerance and its association with age, nutritional status, birth weight, dehydration and enteropathogenic agents identified in fecal samples. After been rehydrated the infants received whole cow' milk assuring the intake of 100 kcal/kg per day. Lactose intolerance was defined according t the following criteria: 1) persistence of diarrhea associated with weight loss during 48 hours, 2) development of vomiting and/or abdominal distention associated with excretion of carbohydrate in feces and/or acids tools, 3) metabolic acidosis associated with abdominal distention at anytime of refeeding period. Lactose intolerance was detected in 52.1% (162/311) of the patients and it was significantly associated with age under 6 months (P < 0.01), birth weight under 3000 grams (P < 0.01), development of dehydration (P < 0.01) and with enteropathogenic Escherichia coli (EPEC) serotypes infection (P < 0.01).


Assuntos
Diarreia Infantil/complicações , Infecções por Escherichia coli/complicações , Intolerância à Lactose/etiologia , Doença Aguda , Fatores Etários , Peso ao Nascer , Desidratação , Diarreia Infantil/microbiologia , Fezes/química , Fezes/microbiologia , Feminino , Hospitalização , Humanos , Lactente , Masculino , Estado Nutricional , Estudos Prospectivos
10.
Arq. bras. cardiol ; 39(6): 399-404, 1982.
Artigo em Português | LILACS | ID: lil-12349

RESUMO

Os autores apresentam um caso de estenose aortica supravalvar associada a anomalia facial e a retardo mental, caracterizando a sindrome de Williams-Beuren. Sao abordados os aspectos etiologicos, o quadro clinico, os metodos de exames complementares de diagnostico e o tratamento cirurgico


Assuntos
Humanos , Feminino , Adolescente , Deficiência Intelectual , Anormalidades Múltiplas , Estenose da Valva Aórtica
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