Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Tex Heart Inst J ; 12(2): 195-7, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15227031

RESUMO

An otherwise healthy, apparently normal 45-year-old man underwent a triple coronary artery bypass procedure, complicated only by modest postoperative bleeding. He had received aspirin and dipyridamole preoperatively, and was given 1 unit of packed red cells and 4 units of fresh frozen plasma on the day of operation. Fifteen months later, malaise and diffuse lymphadenopathy developed. Lymph node biopsy and immune studies were characteristic of the AIDS prodrome. This experience emphasizes the need for control of bleeding and the avoidance of blood products wherever possible.

2.
Cancer Res ; 44(5): 2225-35, 1984 May.
Artigo em Inglês | MEDLINE | ID: mdl-6713411

RESUMO

Administration of plasma perfused over Protein A immobilized in collodion-charcoal produced focal acute tumor necrolytic reactions in breast adenocarcinomas. With repeated procedures, objective tumor regressions were observed in four of the first five consecutive patients treated. Within 4 to 48 hr after treatments, tumors became hyperemic and edematous, often with the appearance of focal vesicles. Microscopic and ultrastructural evaluation demonstrated a spectrum of lesions in cytoplasm and nucleus of tumor cells indicative of lethal and sublethal changes. With further treatments, more pronounced degenerative changes in individual tumor cells, tumor nodules, and intervening stroma were apparent. Furthermore, increased luminal and abluminal vesiculation of endothelial cells of postcapillary venules adjacent to tumor nodules was noted. With continued treatments at intervals of 2 to 3 days, some tumor sites showed focal mononuclear cell infiltration, and at the conclusion of plasma perfusion treatments previously ulcerated tumor foci were replaced by granulation tissue. These data suggest that several cytotoxic and inflammatory mechanisms are activated simultaneously or in succession and may account for the tumoricidal effects noted following repeated plasma perfusions.


Assuntos
Adenocarcinoma/patologia , Neoplasias da Mama/patologia , Proteína Estafilocócica A/uso terapêutico , Adenocarcinoma/terapia , Adenocarcinoma/ultraestrutura , Neoplasias da Mama/terapia , Neoplasias da Mama/ultraestrutura , Feminino , Humanos , Microscopia Eletrônica , Pessoa de Meia-Idade , Perfusão
4.
Cancer Invest ; 1(1): 25-40, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6667397

RESUMO

The presence of common nucleolar antigens in a broad array of human malignant tumors has led to several lines of investigations. In addition to studies on an increasing number of benign and malignant neoplasms with a variety of antibodies designed to statistically evaluate the presence of nucleolar antigens, purification procedures and chemical analyses are being used to characterize the specific antigens. The localization of the nucleolar antigens in HeLa cells was studied by the postembedding immunoelectron microscopic procedure employing rabbit antibodies to nucleoli or nuclear Tris extracts of these cells. The products of the peroxidase-antiperoxidase complexes visualized by the reaction with diaminobenzidine in nucleoli were mainly found in the nucleolonemas which contain the dense nucleolar RNP components. When these nucleoli became compact after treatment of HeLa cells with adriamycin, the distribution of the immunoreactive products was altered along with distribution of the dense nucleolar components. The human nucleolar antigens were mainly localized to nucleolar regions containing the nucleolar RNP components. Improved purification of the antigens made it possible to provide a satisfactory amino acid analysis of one pI 6.3 antigen. Interestingly, some of the nucleolar antigen was found in miniparticle undescribed until now.


Assuntos
Antígenos de Neoplasias/isolamento & purificação , Nucléolo Celular/imunologia , Neoplasias/imunologia , Aminoácidos/análise , Cromatografia de Afinidade , Células HeLa , Humanos , Focalização Isoelétrica , Microscopia Eletrônica , Neoplasias/ultraestrutura
6.
Cancer Res ; 41(10): 4020-6, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7197192

RESUMO

cis-Diamminedichloroplatinum(II) was found to bind to covalently closed circular supercoiled, covalently closed circular nonsupercoiled, and single-strand broken relaxed PM2 DNA and induce different types of DNA conformational changes. Using Kleinschmidt's technique, it was found that binding of cis-diamminedichloroplatinum(II) decreased the DNA length to 75% of the original single-strand broken relaxed DNA without inducing superhelical conformational changes. cis-Diamminedichloroplatinum(II) also shortened the length of covalently closed circular nonsupercoiled DNA before a supercoiled conformation was generated. Single strand-specific nucleases were used to detect drug-induced DNA structural alterations. Local single-strand regions or regions of denaturation were detected by S1 nuclease from Aspergillus oryzae and by BAL-31 nuclease from Alteromonas espejiana BAL-31. The single-strand regions or local denaturation regions do not seem to be related to or caused by DNA superhelical conformational changes since they were detected at drug concentrations at which no significant DNA superhelical turns were found. DNA shortening, superhelical conformational changes, and local denaturation regions can be explained by the previously proposed "DNA intrastrand cross-linking" model (Stone et al., J. Mol. Biol., 104: 793-801, 1976).


Assuntos
Cisplatino/farmacologia , DNA/metabolismo , Cisplatino/metabolismo , DNA de Cadeia Simples/metabolismo , DNA Super-Helicoidal/metabolismo , Desoxirribonucleases/metabolismo , Modelos Químicos , Conformação de Ácido Nucleico/efeitos dos fármacos
7.
Cell Biol Int Rep ; 4(11): 997-1007, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7438225

RESUMO

Treatment of isolated nucleoli with Sarkosyl (2%) dissociated 99.5% of the proteins. The residual DNA-protein complex contained the endogenous transcriptional activity which had a high fidelity of RNA synthesis. Electron microscopic analysis of this residue fraction showed the presence of 150-200A diameter protein globules present along the length of some of the DNA fibers. SDS-polyacrylamide gel electrophoretic analysis of the proteins of the complex indicated that the subunits of purified RNA polymerase I were only a minor component of this complex. Associated with the complex were the U3 and 5S RNA.


Assuntos
Nucléolo Celular/análise , Precursores de Ácido Nucleico/genética , Proteínas/análise , RNA Ribossômico/genética , Transcrição Gênica , Animais , Linhagem Celular , Nucléolo Celular/metabolismo , Detergentes/farmacologia , Neoplasias Hepáticas Experimentais , RNA Polimerase I/análise , Ratos
11.
Cancer Res ; 40(2): 261-7, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7356509

RESUMO

The intravesical administration of mitomycin C to normal and N-[4-(5-nitro-2-furyl)-2-thiozolyl]formamide-induced bladder tumor-carrying mice at initial concentrations of 2 and 5 mg/ml for 2 hr resulted in marked morphological effects including cytoplasmic and nuclear abnormalities and disruption of surface architecture. Tumors cells and normal urothelial cells were sensitive to the effects of mitomycin C. These effects were limited to epithelial cells.


Assuntos
FANFT , Mitomicinas/administração & dosagem , Tiazóis , Neoplasias da Bexiga Urinária/tratamento farmacológico , Bexiga Urinária/efeitos dos fármacos , Animais , Epitélio/efeitos dos fármacos , Feminino , Camundongos , Microscopia Eletrônica , Neoplasias Experimentais/tratamento farmacológico , Bexiga Urinária/ultraestrutura , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/ultraestrutura
13.
J Cell Biol ; 83(2 Pt 1): 462-7, 1979 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-227916

RESUMO

Nonhistone protein BA has been shown to decrease in amount in the chromatin of growth- stimulated normal rat liver (Yeoman et al. 1975. Cancer Res. 35:1249-1255) and in mitogen-stimulated normal human lymphocytes (Yeoman et al. 1976. Exp. Cell Res. 100:47- 55.). Subsequently, protein BA was purified and was shown to prefer to bind to double- stranded A-T-rich DNAs (Catino et al. 1978. Biochemistry. 17:983-987.). Immunization of rabbits with highly purified protein BA has resulted in the production of a specific antibody. A specific immunoreactivity for chromosomal protein BA has been demonstrated by immunoelectrophoresis and double antibody immunoprecipitation analysis with rabbit anti-BA immunoglobulin and IgG fractions. Light microscope examination of normal rat liver crysections by the indirect immunofluorescence procedure has demonstrated a cytoplasmic as well as a nuclear localization for protein BA with a pronounced perinucleolar fluorescence. Immunoelectron microscopy employing the peroxidase antiperoxidase method of antigen localization has confirmed the immunofluorescence data and has show a heterochromatin localization for protein BA. The relationship of the localization of protein BA to gene control in quiescent cells or to configurations of heterochromatin as well as the marked reduction in the amounts of protein BA which occur in stimulated growth states remains to be defined.


Assuntos
Núcleo Celular/análise , Citoplasma/análise , DNA Helicases/análise , Animais , Nucléolo Celular/análise , Imunofluorescência , Heterocromatina/análise , Técnicas Imunoenzimáticas , Fígado/ultraestrutura , Microscopia Eletrônica , Ratos
15.
Cancer Res ; 39(4): 1239-44, 1979 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-421207

RESUMO

Male Sprague-Dawley rats were treated with carminomycin i.v. in doses ranging from 1 to 40 mg/kg. Within 1 hr after the administration of carminomycin, 20 mg/kg, nucleoli of cardiac and skeletal muscle cells were segregated, while nucleoli of liver parenchyma cells were unaffected. Three and one-half hr after drug administration, cardiac muscle nucleoli reverted to normal ultrastructure. However, some skeletal muscle cell nucleoli were still segregated. Following treatment with carminomycin, 10 mg/kg, no significant ultrastructural changes were observed. These results demonstrate that at sufficiently high doses carminomycin induces ultrastructural lesions in nucleoli of both cardiac and muscle cells. The dose of carminomycin required to produce nucleolar segregation in cardiac and skeletal muscle is 6 times greater than the dose of Adriamycin (3.5 mg/kg) required to induce equivalent alterations.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Carrubicina/farmacologia , Nucléolo Celular/efeitos dos fármacos , Coração/efeitos dos fármacos , Músculos/efeitos dos fármacos , Animais , Nucléolo Celular/ultraestrutura , Doxorrubicina/farmacologia , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Microscopia Eletrônica , Músculos/ultraestrutura , Miocárdio/ultraestrutura , Ratos
16.
Cancer Res ; 39(3): 857-63, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-85481

RESUMO

With the aid of a simple silver-staining procedure, large numbers and unusual arrays of nucleolar argyrophilic granules were found in Novikoff hepatoma, KB, and HeLa cells. Some of these arrays consisted of linearly arranged discrete granules, and others were in two to three rows each containing three to five granules. Corresponding formations were not found in either the normal or regenerating liver nucleoli which contained an argyrophilic network in which the dark granules were apparently associated with the less dark argyrophilic fibrils of a reticulum. The nucleolar argyrophilic granules were readily identifiable in the separated daughter nuclei of the tumor cells in telophase, suggesting that the increased nucleolar activity of the G1 phase begins in these cells even before cell division has been completed.


Assuntos
Nucléolo Celular/ultraestrutura , Células HeLa/ultraestrutura , Neoplasias Hepáticas Experimentais/ultraestrutura , Animais , Divisão Celular , Nucléolo Celular/metabolismo , Feminino , Humanos , Fígado/ultraestrutura , Neoplasias Hepáticas Experimentais/metabolismo , Regeneração Hepática , Precursores de Ácido Nucleico/biossíntese , RNA Neoplásico/biossíntese , RNA Ribossômico/biossíntese , Ratos , Prata , Coloração e Rotulagem
17.
Acta Biol Acad Sci Hung ; 30(3): 257-64, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-550663

RESUMO

The influence of the extraction of hnRNP (informofer) particles on the ultrastructural appearance of the perichromatin granules was studied. The extraction of hnRNP particles was carried out by SAMARINA's procedure from the rat liver nuclear fraction. The extraction did not change the numbers and the general ultrastructural features of perichromatin granules. It is therefore unlikely that the perichromatin granules are the morphological representatives of storaged or transported hnRNA.


Assuntos
Cromatina/ultraestrutura , Fígado/ultraestrutura , Nucleoproteínas/isolamento & purificação , Ribonucleoproteínas/isolamento & purificação , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Cicloeximida/farmacologia , Ribonucleoproteínas Nucleares Heterogêneas , Masculino , RNA Nuclear Heterogêneo/isolamento & purificação , Ratos
18.
Mutat Res ; 52(2): 199-206, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-740006

RESUMO

This study is the first report of scanning-electron microscopy of isolated and purified metaphase chromosomes containing drug-induced aberrations. The technique reported allows high resolution topological examination of chromosomal aberrations which may pass undetected with conventional techniques.


Assuntos
Aberrações Cromossômicas , Cromossomos/ultraestrutura , Microscopia Eletrônica de Varredura/métodos , Linhagem Celular , Cromossomos/efeitos dos fármacos , Doxorrubicina/farmacologia , Mutagênicos
20.
Cancer Treat Rep ; 62(5): 771-8, 1978 May.
Artigo em Inglês | MEDLINE | ID: mdl-657162

RESUMO

Male Sprague-Dawley rats were treated with either 2.5, 3.5, or 5.0 mg/kg of adriamycin by iv injection. After 1 or 3 hours of treatment, samples of liver, cardiac muscle, and skeletal muscle cells were examined by electron microscopy. The changes in ultrastructure observed in these tissues after the first hour included nucleolar segregation and altered distribution of the perinucleolar chromatin. However, no alterations in the ultrastructure of either the nucleus or cytoplasm were observed in tissues examined 3 hours after a 5-mg/kg dose of adriamycin. The doses at which nucleolar alterations occurred varied between tissues. In skeletal and cardiac muscle cells, marked alterations in nucleolar ultrastructure were observed at doses of 3.5 and 5.0 mg/kg of adriamycin. Liver cell nucleoli, however, exhibited few structural aberrations at these doses. The similarities in response of skeletal and cardiac muscle suggest that ultrastructural analysis of skeletal muscle biopsies may be useful in evaluating adriamycin cardiotoxicity.


Assuntos
Nucléolo Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Fígado/efeitos dos fármacos , Músculos/efeitos dos fármacos , Miocárdio/ultraestrutura , Animais , Fígado/ultraestrutura , Masculino , Músculos/ultraestrutura , Ratos , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...