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1.
Gynecol Oncol ; 72(3): 306-11, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10053100

RESUMO

OBJECTIVE: Expression of the immunoreactive protein of matrix metalloproteinase 2 (MMP-2) was studied in cervical tumors representing various stages of cell atypia and differentiation. In this study, we evaluated whether the expression of MMP-2 is an early or late event in the process of dedifferentiation and cancer progression. METHODS: Paraffin tissue sections from 60 cervical neoplasias including 38 cervical intraepithelial neoplasias (CINs) and 22 early-stage (stage IB and IIA) squamous cervical carcinomas were studied with respect to the expression of MMP-2 protein by using immunoperoxidase staining. RESULTS: The staining pattern of MMP-2 in the CIN lesions usually differed from that in squamous carcinoma. Latent MMP-2 protein localized, in most of the cases, to the periphery of the CIN cells, but was diffuse in the cytoplasm of the carcinoma cells. No correlation was found between overexpression of MMP-2 protein and degree of dysplasia, nor was there any association between MMP-2 and human papillomavirus (HPV). High scores for MMP-2 were observed only in histologically higher-grade early-stage cervical carcinomas. The lymph node metastases derived from high-MMP-2-score primary tumors were also positive for MMP-2. No correlation between MMP-2 staining and clinical course or prognosis was found. CONCLUSIONS: MMP-2 expression is an early event during dedifferentiation and malignant transformation in cervical neoplasias. The pattern of staining is different in CIN than in squamous carcinoma cells, in which overexpression may correlate with the degree of anaplasia.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/patologia , Gelatinases/metabolismo , Metaloendopeptidases/metabolismo , Displasia do Colo do Útero/enzimologia , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/patologia , Transformação Celular Neoplásica , Células Epiteliais/enzimologia , Feminino , Humanos , Imuno-Histoquímica , Metaloproteinase 2 da Matriz , Estadiamento de Neoplasias
2.
J Nematol ; 30(4): 391-403, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19274231

RESUMO

The ultrastructure of spermatozoa in the free-living marine nematode Halalaimus dimorphus was studied with transmission electron microscopy. Spermatozoa in the posterior testis of the male had a large cavity filled with cellular processes, which contained a variable number of small tubules. Mitochondria and small tubules were the only cell structures observed in the cytoplasm. The spermatozoa had a bipolar structure. The anteriorly situated nucleus, which was electron-dense and homogeneous, was surrounded by a single membrane. The size of the small tubules in the cytoplasm (diam. 12-13 nm) and their relatively thick wall structure suggested that they were not normal microtubules (diam. 25 nm). The material of the small tubules was assumed to be major sperm protein (MSP). The cavity appeared to open on the surface of the spermatozoon at the posterior extremity of the cell, and also medially, at the level of the anterior end of the cavity. The pores apparently were closed by a special plug-like structure, which was an evagination of the cell. The wall of the cavity was characterized by longitudinal folds, which were mushroom-shaped in transverse section. Spermatids in the anterior testis of H. dimorphuswere characterized by fibrous bodies packed with small tubules and by cellular processes also containing small tubules. H. dimorphus sperm seem to perform swimming movements based on liquid currents commonly present in turbin-like systems. Spermatogenesis resembled that found in ticks.

3.
J Nematol ; 29(1): 65-81, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19274135

RESUMO

The free-living nematodes Eumonhystera borealis n. sp., Sphaerolaimus occidentalis n. sp., and S. gracilis de Man 1876 from Bothnian Bay in the northern Baltic Sea are described and illustrated. Eumonhystera borealis n. sp. differs from other species by its small body size (314-393 mum), narrow body (a = 37-49), and large anterior amphids. In Sphaerolaimus occidentalis n. sp. the amphids are posterior to the buccal cavity, and it differs from other similar species by having two sclerotized rings in the posterior part of the buccal cavity. An intersex is reported for S. gracilis. Sphaerolaimus gracilis is cannibalistic or a predator of other species, with a preference for E. borealis n. sp. Sphaerolaimus occidentalis n. sp. coexists with S. gracilis at depths of 80 m but not at 12 m.

4.
J Nematol ; 27(2): 222-30, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19277283

RESUMO

Ethmolaimus hailuotoensis n. sp. from Bothnian Bay, northern Baltic Sea, is described and illustrated. Ethmolaimus hailuotoensis n. sp. has a strongly sclerotized luminal lining of the terminal esophageal bulb and esophagus. The most characteristic feature is a lateral series of large concentric, sclerotized rings with a fine, internal longitudinal oval sclerotization. In addition, E. hailuotoensis n. sp. is distinguished from other Ethmolaimus species by its smaller body size, fewer number of precloacal supplements (7-8), conical tail, and the position of amphid posterior to the buccal cavity. Females of E. hailuotoensis n. sp. studied were hermaphroditic. Ethmolaimus hailuotoensis n. sp. coexisted with E. pratensis. Ethmolaimus pratensis from Bothnian Bay has a characteristic row of sublateral hypodermal glands, a character not before seen in Ethmolaimidae.

5.
J Nematol ; 25(4): 616-24, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19279818

RESUMO

The structure of coelomocytes in the adenophorean aquatic nematode Sphaerolaimus gracilis de Man 1876 was studied with light and electron microscopes. Acid phosphatase and catalase activities were demonstrated by electron microscopy. Two pairs of coelomocytes occurred laterally posterior to the esophagointestinaljunction. The anterior pair of the coelomocytes, with the renette cell and gonad, lay in either the left or the right lateral side of the body. The posterior pair of coelomocytes was in the opposite side of the body, usually posterior to the renette. A long, thin, cell-extension-like structure appeared to originate from the coelomocytes. Coelomocytes were characterized by specialized organelles (CC-organelle) and large vacuoles. The CC-organelle contained crystalline structures like those in peroxisomes. Acid phosphatase and catalase activities were detected in the matrix of CC-organelles and catalase activity in the vacuoles. It was assumed that vacuoles originate from the CC-organelles. Coelomocytes showed pinocytotic activities, and numerous vesicles were observed between the cell membranes and the vacuoles.

6.
Biochim Biophys Acta ; 483(1): 215-9, 1977 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-406932

RESUMO

Lysyl hydroxylase (peptidyllysine, 2-oxoglutarate: oxygen 5-oxidoreductase, EC 1.14.11.4) has a high affinity for columns of concanavalin A-agarose, which was markedly reduced in the presence of alpha-methyl-D-mannoside, suggesting that the enzyme is a glycoprotein. Once bound, the enzyme could not be eluted with the glycoside alone, whereas an effective elution was achieved by a combination of alpha-methyl-D-mannoside and ethylene glycol. The data thus suggest that hydrophobic interaction stabilized the complex of the enzyme with the column. This information was applied to obtain a lysyl hydroxylase purification of about 3000-fold with a recovery of more than 10% from extract of chick embryos by relatively simple steps.


Assuntos
Oxigenases de Função Mista/isolamento & purificação , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/isolamento & purificação , Animais , Embrião de Galinha , Cromatografia de Afinidade , Cromatografia em Gel , Concanavalina A , Etilenoglicóis , Metilmanosídeos , Peso Molecular , Sefarose
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