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1.
Cancer Res ; 43(2): 934-9, 1983 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6848204

RESUMO

Several markers of initial bladder carcinomas described recently may be clinically significant predictors of biological behavior of future recurrences. Comparison of the marker systems and assessment of the value of using multiple markers have been difficult, because the various markers have been studied in different patients. In this study, we compared four markers [chromosome mode, marker chromosomes, and expression of the ABH "blood group" antigens and the Thomsen-Friedenreich antigen (using immunoperoxidase or lectin immunoperoxidase methods)] in 39 patients presenting initially with low-stage bladder carcinoma and followed 3 to 11 years or until deep muscle invasion occurred. Each of the markers was significantly related to subsequent recurrences with deep muscle invasion, and each marker system was able to identify those patients with a very low risk of subsequent invasion. For detection of a subpopulation of patients with Grade II carcinomas who were at high risk for development of subsequent invasion, combinations of markers, especially hyperdiploidy and abnormal expression of the Thomsen-Friedenreich antigen, were significantly more effective than any single marker system.


Assuntos
Sistema ABO de Grupos Sanguíneos , Antígenos Glicosídicos Associados a Tumores , Carcinoma de Células de Transição/diagnóstico , Dissacarídeos/análise , Neoplasias da Bexiga Urinária/diagnóstico , Adulto , Idoso , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/imunologia , Aberrações Cromossômicas , Transtornos Cromossômicos , Feminino , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/imunologia
2.
Cancer Res ; 60(15): 4033-6, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10945604

RESUMO

Good models for the investigation of human prostate cancer are few. Cells from approximately 9.2-21 ml of peripheral blood from patients with metastatic prostate cancer or metastatic colon cancer were injected s.c. into nude mice. Prostate cancer from 2 of 11 patients and colon cancer from 1 of 3 patients were found to be growing as metastases in the lungs of the nude mice. To our knowledge, this is the first report of the formation of xenografts from carcinoma cells taken directly from the peripheral blood of patients. Expanding circulating cancer cells with this approach may have important translational applications including: (a) development of models of human cancers; and (b) sampling of cancers from specific patients for novel molecular and therapeutic approaches.


Assuntos
Transplante de Neoplasias , Células Neoplásicas Circulantes/patologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Transplante Heterólogo , Animais , Divisão Celular , Neoplasias do Colo/sangue , Neoplasias do Colo/patologia , Humanos , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Camundongos Nus
3.
Leukemia ; 17(5): 965-71, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12750711

RESUMO

WT1 is expressed in hematopoietic progenitor cells and in acute leukemia, but its role in normal and malignant hematopoiesis has not been clearly defined. Alternative splicing of the WT1 mRNA yields several protein isoforms with distinct DNA binding and transcriptional regulatory activities. In this study, we investigated the effect of the WT1 isoform lacking two alternatively spliced sequences (WT1 (-/-)) in 32D cl3 cells, a murine myeloid progenitor cell line. The expression of WT1 (-/-) accelerated the granulocyte-colony stimulating factor (G-CSF)-mediated differentiation of these cells, as judged by morphology and by the expression of differentiation-associated genes and cell surface antigens. WT1 (-/-) inhibited G1/S progression in G-CSF but not in interleukin-3, potentially accounting for its ability to accelerate differentiation. It is likely that dominant-negative mutants previously reported in leukemia patients participate in leukemogenesis by inhibiting this function of the wild-type protein.


Assuntos
Diferenciação Celular , Granulócitos/citologia , Proteínas WT1/fisiologia , Processamento Alternativo , Animais , Northern Blotting , Western Blotting , Linhagem Celular , Transformação Celular Neoplásica/genética , Primers do DNA/química , Citometria de Fluxo , Fase G1/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Genes do Tumor de Wilms/fisiologia , Fator Estimulador de Colônias de Granulócitos/farmacologia , Células-Tronco Hematopoéticas , Homozigoto , Humanos , Interleucina-3/metabolismo , Camundongos , Isoformas de Proteínas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fase S/efeitos dos fármacos , Transfecção , Zinco/farmacologia
4.
Prog Mol Subcell Biol ; 14: 89-113, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8061886

RESUMO

The results of our previous studies (Jamison et al. 1988, 1989, 1990 a, b, c, d, e) have shown that the ability of intercalative dyes to modulate the antiviral activity of poly r(A-U) is related to the groove through which the dyes intercalate into the poly r(A-U). When poly r(A-U) is combined with the minor groove intercalating dyes or the minor/major groove intercalating dyes, optimum enhancement of antiviral activity is observed at the dye/ribonucleotide ratio predicted by the neighbor exclusion model (usually 1/4 or 1/6). No enhancement is observed when poly r(A-U) is combined with major groove intercalating dyes. When poly r(A-U) is combined with additional intercalative dyes to produce a dye/ribonucleotide ratio of 1/4 and a ribonucleotide concentration of 200 microM, the antiviral activity of poly r(A-U) is enhanced 8- to 20-fold, while 50% effective doses of the poly r(A-U) and the dyes decreases 18- to 347-fold. Interferon neutralization assays demonstrate that the interferon-inducing capability of the dye/poly r(A-U) combinations approximates the sum of the interferon-inducing capabilities of the poly r(A-U) and the dyes employed and suggests that the dyes potentiate the antiviral activity of poly r(A-U) without affecting the amount of interferon induced. Direct viral inactivation studies demonstrate that the dyes, poly r(A-U), and the dye/poly r(A-U) combinations do not inactivate VSV at concentrations near the 50% viral inhibitory dose. Assessment of cytotoxicity by microscope examination of HSF cell morphology and trypan blue exclusion indicates that the dye/poly r(A-U) combinations exhibit antiviral activity at concentrations well below those that induce cyto-toxicity. Several of the dyes and the dye/poly r(A-U) combinations exhibit anti-HIV-1 activity, suggesting that the enhancement phenomenon is not virus-specific nor host cell-specific. The enhancement phenomenon is sensitive to the base sequence of the polynucleotide with dye/poly r(A-U) and dye/poly r(G-C) combinations displaying enhanced antiviral activity, while dye/poly (rI).poly (rC) and dye/poly d(A-T) combinations do not. These results suggest that while intercalation of the dye and interferon induction are necessary for enhanced antiviral activity, neither intercalation nor interferon induction alone is sufficient to potentiate the antiviral activity of polyribonucleotides.


Assuntos
Antivirais/toxicidade , Corantes/toxicidade , Poli A-U/toxicidade , RNA de Cadeia Dupla/toxicidade , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
5.
Curr Med Chem ; 9(24): 2271-85, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12470246

RESUMO

The decision of stressed cells to die or to survive is made by integrating signals at different levels through multiple check points. However, initiation and continued progression toward cell death by apoptosis in cancer cells may be blocked by mutation of the tumor suppressor p53 or overexpression of members of the bcl-2 family of proteins. The existence of such mechanisms indicates that cancer cells lose the controls regulating their cell cycle. Therefore, the activation of their programmed cell death appears as a major therapeutic target. Oxidative stress can stimulate growth, trigger apoptosis, or cause necrosis depending upon the dose and the exposure time of the oxidizing agent. A large body of evidence supports the idea that oxidative stress induced by redox cycling of vitamins C and K(3) in association surpasses cancer cellular defense systems and results in cell death. The molecular mechanisms underlying such a process are, however, still unknown. Indeed, several types of cell death may be produced, namely autoschizis, apoptosis and necrosis. Combined vitamin C and K(3) administration in vitro and in vivo produced tumor growth inhibition and increased the life-span of tumor-bearing mice. CK(3)-treatment selectively potentiated tumor chemotherapy, produced sensitization of tumors resistant to some drugs, potentiated cancer radiotherapy and caused inhibition of the development of cancer metastases without inducing toxicity in the host. We propose the association of vitamins C and K(3) as an adjuvant cancer therapy which may be introduced into human cancer therapy without any change in the classical anticancer protocols, and without any supplementary risk for patients.


Assuntos
Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Neoplasias/tratamento farmacológico , Vitamina K 3/uso terapêutico , Animais , Morte Celular/efeitos dos fármacos , Quimioterapia Adjuvante , Sinergismo Farmacológico , Camundongos , Neoplasias/patologia , Neoplasias/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Células Tumorais Cultivadas
6.
J Histochem Cytochem ; 49(1): 109-20, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11118483

RESUMO

Human prostate cancer cells (DU145) implanted into nude mice are deficient in DNase activity. After administration of a vitamin C/vitamin K(3) combination, both alkaline DNase (DNase I) and acid DNase (DNase II) activities were detected in cryosections with a histochemical lead nitrate technique. Alkaline DNase activity appeared 1 hr after vitamin administration, decreased slightly until 2 hr, and disappeared by 8 hr after treatment. Acid DNase activity appeared 2 hr after vitamin administration, reached its highest levels between 4 and 8 hr, and maintained its activity 24 hr after treatment. Methyl green staining indicated that DNase expression was accompanied by a decrease in DNA content of the tumor cells. Microscopic examination of 1-microm sections of the tumors indicated that DNase reactivation and the subsequent degradation of DNA induced multiple forms of tumor cell death, including apoptosis and necrosis. The primary form of vitamin-induced tumor cell death was autoschizis, which is characterized by membrane damage and the progressive loss of cytoplasm through a series of self-excisions. These self-excisions typically continue until the perikaryon consists of an apparently intact nucleus surrounded by a thin rim of cytoplasm that contains damaged organelles.


Assuntos
Ácido Ascórbico/uso terapêutico , Desoxirribonucleases/metabolismo , Reativadores Enzimáticos/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Vitamina K/uso terapêutico , Animais , Ácido Ascórbico/farmacologia , Morte Celular/efeitos dos fármacos , Corantes , Sinergismo Farmacológico , Reativadores Enzimáticos/farmacologia , Histocitoquímica , Humanos , Chumbo , Masculino , Verde de Metila , Camundongos , Camundongos Nus , Microscopia Eletrônica , Nitratos , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Vitamina K/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Am J Clin Pathol ; 77(6): 692-9, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7091049

RESUMO

Tumor deletion of the ABH blood group antigens (BGAg) heralds an unfavorable prognosis in human bladder cancer. The T antigen (Thomsen-Friedenreich antigen: TAg), a precursor of other BGAg, has previously been found in malignant but not most normal cells, in which the TAg is cryptic but can be unmasked with neuraminidase (NMD). We investigated the prognostic significance of TAg expression in bladder cancer by staining paraffin sections with a T-specific lectin (peanut agglutinin [PNA]) immunoperoxidase technic. Seventy-two cases of low grade, low stage bladder cancer, 21 cases of high grade bladder cancer, and 68 controls were studied. All normals expressed the TAg only after NMD treatment (Cryptic TAg+). The Grade III cancers, all invasive, either expressed the TAg (TAg+)(67%) or lacked T even after NMD (Cryptic TAg-) (29%), indicating that the T structure was lost rather than masked as in normal tissue. Thirty-nine per cent of 23 Grade I and II cancers which were TAg+ or Cryptic TAg- subsequently became invasive (Stage B), compared with 10% of 49 Cryptic TAg+ cancers. For 32 Grade I and II, ABH BGAg negative cancers, 64% of TAg+ or Cryptic TAg- cancers became invasive, compared with 17% of cancers which had Cryptic TAg+. Thus, the TAg may be a prognostically useful immunohistochemical tumor marker in bladder cancer, especially for tumors negative for ABH BGAg.


Assuntos
Antígenos de Neoplasias/análise , Carcinoma de Células de Transição/imunologia , Neoplasias da Bexiga Urinária/imunologia , Sistema ABO de Grupos Sanguíneos , Antígenos/análise , Carcinoma de Células de Transição/diagnóstico , Endotélio/imunologia , Humanos , Sistema do Grupo Sanguíneo MNSs , Recidiva Local de Neoplasia , Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/diagnóstico
8.
Urology ; 25(3): 239-41, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2579499

RESUMO

Fifty consecutive patients with large gland prostatic hypertrophy, requiring open prostatectomy, were analyzed retrospectively with regard to relationship to the subsequent development of ischemic heart disease. A significant increase in the development of progressive ischemic heart disease and sudden death was found in these patients when compared with two control groups. These findings are analyzed.


Assuntos
Doença das Coronárias/etiologia , Hiperplasia Prostática/complicações , Idoso , Morte Súbita/epidemiologia , Complicações do Diabetes , Seguimentos , Humanos , Masculino , Infarto do Miocárdio/etiologia , Tamanho do Órgão , Próstata/patologia , Prostatectomia , Hiperplasia Prostática/patologia , Hiperplasia Prostática/cirurgia , Estudos Retrospectivos , Fatores de Tempo
9.
Urology ; 43(3): 333-6, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8134988

RESUMO

OBJECTIVE: To assess feasibility of early discharge of patients after transurethral resection of the prostate (TURP) with an indwelling Foley catheter. METHODS: A retrospective study comparing a planned early discharge group and a standard post-TURP group. Comprising the study group were 47 consecutive TURP patients treated with the intent to be discharged early with an indwelling Foley catheter. The comparative group included 50 consecutive patients with the standard post-TURP hospital course. RESULTS: Twenty-seven of 47 patients (57%) in the study group were discharged on postoperative day 1 and a total of 43 (91%) were released within two days. Mean length of stay was 1.7 days. Four patients (8.5%) had medical problems prolonging stay. There were eight emergency room visits secondary to catheter problems or failed voiding trials. In the comparative group of 50 consecutive patients the mean length of stay was 3.9 days. Five of 50 patients (10%) had medical problems prolonging stay. CONCLUSIONS: Complications were similar in each group. No readmissions or serious morbidities were noted in the patients with shortened hospital stay. Early discharge of post-TURP patients is a safe, feasible, and cost-effective alternative.


Assuntos
Cateteres de Demora , Tempo de Internação , Alta do Paciente , Prostatectomia , Cateterismo Urinário , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Uretra
10.
Urology ; 4(1): 95-6, 1974 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21322994

RESUMO

A case of fatal air embolism following a routine air cystometrogram is reported. This is the first apparent complication of this type reported with air cystometrogram.


Assuntos
Embolia Aérea/etiologia , Idoso , Evolução Fatal , Humanos , Masculino , Manometria/efeitos adversos , Manometria/instrumentação , Doenças da Bexiga Urinária/diagnóstico
11.
Life Sci ; 59(17): 1389-400, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8890917

RESUMO

A micro-tetrazolium assay was employed to evaluate vitamin C (VC), vitamin K3 (VK3) and vitamin C/vitamin K3 combinations (VC/VK3) for their antitumor activity against eight human urologic tumor cell lines. While the individual vitamins exhibited antitumor activity at high concentrations, co-administration of the vitamins in a VC : VK3 ratio of 100 : 1 potentiated antitumor activity 4- to 61-fold even when exposure times were as short as 1 hour. Administration of exogenous catalase destroyed the antitumor activity of the vitamins and suggested that hydrogen peroxide and perhaps other reactive oxygen species were involved in the antitumor mechanism of these vitamins. Electron micrographs taken in a previous study demonstrated that vitamin treatment damaged mitochondria and may have impaired ATP synthesis. Analysis of cellular ATP and thiol levels as well as DNA and protein synthesis during the first five hours following a one hour VC/VK3 treatment, revealed: a transient increase in ATP production, a substantial decrease in DNA synthesis, an increase in protein synthesis and a decrease in thiol levels. These results suggested that redox cycling of the vitamin combination increased oxidative stress until it surpassed the reducing ability of the cellular thiols and cellular or genetic damage ensued.


Assuntos
Ácido Ascórbico/farmacologia , Neoplasias Urogenitais/patologia , Vitamina K/farmacologia , Trifosfato de Adenosina/metabolismo , Replicação do DNA , Sinergismo Farmacológico , Humanos , Microscopia Eletrônica , Espécies Reativas de Oxigênio , Compostos de Sulfidrila/metabolismo , Células Tumorais Cultivadas , Neoplasias Urogenitais/metabolismo , Neoplasias Urogenitais/ultraestrutura
12.
Tissue Cell ; 30(4): 475-84, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9787478

RESUMO

The current study has documented changes in the ultrastructure as well as in the intranucleolar distribution of rDNA and rRNA in RT4 (human transitional cell bladder carcinoma) cell nucleoli following a 3-h exposure to toxic doses of 50 microM ametantrone (AMT), 200 microM poly (adenylate-uridylate) (poly r(A-U) or an AMT/poly r(A-U) combination with an AMT/polyribonucleotide ratio of 1:4 and a poly r(A-U) concentration of 200 microM. While the main nucleolar components (fibrillar center (F), dense fibrillar component (D), granular component (G) and interstices (I) can be discerned following all treatments, the nucleoli exhibit: compaction, segregation, a decrease in the number of F, an increase in the size of remaining F, margination of intranucleolar chromatin and retention of intranucleolar pre-rRNA and rRNA. The relative abilities of the test agents to induce nucleolar compaction are AMT/poly r(A-U) > poly r(A-U) > AMT > sham-treated, while the abilities of the test agents to induce the remaining nucleolar changes are AMT/poly r(A-U) > or = AMT > poly r(A-U) > sham-treated cells. Poly r(A-U) and the induced interferon induce nucleolar compaction, while AMT produces nucleolar segregation. These results are consistent with a model in which the poly r(A-U) and/or the AMT inhibit DNA transcription and rRNA processing as well as the release of nascent preribosomes from the nucleolus.


Assuntos
Antineoplásicos/farmacologia , Nucléolo Celular/química , Mitoxantrona/análogos & derivados , Poli A-U/farmacologia , RNA Neoplásico/análise , Carcinoma de Células de Transição , Nucléolo Celular/efeitos dos fármacos , Nucléolo Celular/ultraestrutura , DNA de Neoplasias/análise , DNA Ribossômico/análise , Humanos , Microscopia Imunoeletrônica , Mitoxantrona/farmacologia , RNA Ribossômico/análise , RNA Ribossômico/ultraestrutura , Células Tumorais Cultivadas/química , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/ultraestrutura , Neoplasias da Bexiga Urinária
13.
Tissue Cell ; 28(6): 687-701, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9004536

RESUMO

Transmission and scanning electron microscopy and flow cytometry were employed to characterize the cytotoxic effects of vitamin C (VC), vitamin K3 (VK3), or VC-VK3 combinations on a human prostate carcinoma cell line (DU145) following a 1-h vitamin treatment and a 24-h incubation in culture medium. Cells exposed to VC exhibited membranous blebs, aberrant microvillar morphology, mitochondria with swollen cristae and intramitochondrial deposits, as well as nucleoli with segregated components. VK3-treated cells displayed a damaged cytoskeleton and membranes, a cytoplasm which contained large lumen, condensed polysomes, and severely damaged mitochondria with residual bodies, and nuclei which exhibited chromatic condensation, pyknosis, and karyolysis. VC-VK3-treated cells exhibited characteristics consistent with necrosis, i.e. swollen mitochondria and swollen, achromatic nuclei with marginated chromatin and intact envelopes, while other cells displayed characteristics consistent with apoptosis, i.e. expulsion of organelle-containing blebs, margination of nuclear chromatin, and segregation of nucleolar components. Vitamin treatment also decreased DNA synthesis, induced a S/G2 block in the cell cycle, and resulted in the accumulation of fragmented DNA. These results suggested that increased oxidative stress, subsequent membrane damage, and DNA fragmentation were responsible for enhanced cytotoxicity of the vitamin combination.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Próstata , Ácido Ascórbico/administração & dosagem , DNA/biossíntese , Sinergismo Farmacológico , Citometria de Fluxo , Hemostáticos/administração & dosagem , Humanos , Masculino , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Timidina/metabolismo , Trítio , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/ultraestrutura , Vitamina K/administração & dosagem
14.
J Anal Toxicol ; 20(6): 506-8, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8889689

RESUMO

A simple procedure was developed to derivatize benzoylecgonine extracted from urine for subsequent confirmation by gas chromatography-mass spectrometry. The compound was esterified with dimethylformamide-dipropylacetal (DMF-DPA) or dimethylformamide-diisopropylacetal (DMF-DIPA) to the corresponding propyl and isopropyl esters. The optimum reaction condition was found to be heating the reaction mixture in the presence of pyridine at 100 degrees C for 30 min. The procedure is a one-step esterification followed by evaporation of excess reagents. When benzoylecgonine was extracted from urine using a solid-phase extraction technique and derivatized with this procedure, the compound was detected at a level as low as 10 ng/mL. Quantitation was linear over the concentration range 10-8000 ng/mL.


Assuntos
Acetais/química , Cocaína/análogos & derivados , Dimetilformamida/química , Piridinas/química , Cocaína/química , Cocaína/urina , Esterificação , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Estereoisomerismo
15.
Scanning ; 19(8): 523-32, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9418206

RESUMO

Transmission electron microscopy and scanning force microscopy of negative-stained, carbon-coated replica and mica-adsorbed preparations of 200 microM poly r(A-U) and 50 microM ethidium bromide/200 microM poly r(A-U) have been employed to evaluate ethidium-induced changes in poly r(A-U) topology. Poly r(A-U) alone exhibits elongated conformations 85-115 nm in length that possess a number of hairpin loops as well as single-stranded domains. While the double-stranded domains are found predominately at the base of the hairpin loops (diameter = 5-30 nm), other rod-like (presumably double-stranded) regions ranging from 25-80 nm in length are present in other portions of the poly r(A-U). In contrast with the poly r(A-U) alone, the EB/poly r(A-U) combination appears as a heterogeneous population of condensed structures whose lengths and widths vary from 12-88 nm and 15-45 nm, respectively. These conformational changes are due to a number of factors, including the displacement of ordered water surrounding the poly r(A-U) and charge shielding of the phosphate groups of the poly r(A-U) upon the binding of the ethidium.


Assuntos
Etídio/química , Microscopia de Força Atômica/métodos , Microscopia Eletrônica/métodos , Modelos Químicos , Poli A-U/química , RNA de Cadeia Dupla/ultraestrutura , Adenina/química , Conformação Molecular , Polímeros , RNA de Cadeia Dupla/química , Uracila/química
16.
Scanning ; 25(3): 137-49, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12866647

RESUMO

Human ovarian carcinoma (MDAH 2774) cells were treated with sodium ascorbate (VC), menadione (VK3), or a combination of both in a ratio 100:1 for 1h and then examined with scanning electron microscopy (SEM) and light microscopy (LM). Light microscopy data corroborated SEM observations, which demonstrated that death of VC+VK3-treated tumor cells occurred primarily by autoschizis. This type of cell death is characterized by a decrease in cell size, cytoplasmic self-excisions, and nuclear and nucleolar morphologic degradations without the formation of apoptotic bodies. Ultimately, cell death results from karyorrhexis and karyolysis. This study illustrates that plasma membrane damage (branching filopodia, blisters, blebs) results from VC treatment; cytoskeletal damage and self-morsellation are caused by VC, VK3 and VC+VK, treatments. The VC treatment results in a 23% decrease in cell diameter while VK3-treated cells decrease cell diameter by 66%. After 1h of VC+VK3 treatment, a heterogenous cell population is found. This population can be resolved into one population whose diameters are 23% smaller than those of sham-treated cells, and a second population whose diameters are approximately twice those of sham-treated cells. This second population is indicative of doublet formation in which the cells appear to be dividing (an early stage of autoschizic cell death). One half of the doublet contains the cell nucleus while the other half consists of cytoplasm and membrane only. The enucleate portion of this doublet will then be excised. When the types of cell death are enumerated following VC+VK3 treatment, 43% of the cells die by autoschizis, 3% by apoptosis, and 1.9% by oncosis. These results confirm that autoschizis is the principal form of cell death that results from the in vitro treatment of human ovarian carcinoma cells with the vitamin combination.


Assuntos
Adenocarcinoma/patologia , Ácido Ascórbico/farmacologia , Morte Celular , Neoplasias Ovarianas/patologia , Vitamina K 3/farmacologia , Quimioterapia Combinada , Feminino , Humanos , Microscopia/métodos , Microscopia Eletrônica de Varredura , Células Tumorais Cultivadas/efeitos dos fármacos
17.
Scanning ; 20(8): 564-75, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9891940

RESUMO

Scanning and transmission electron microscopy and fluorescence light microscopy were employed to characterize the cytotoxic effects of vitamin C (VitC), vitamin K3 (VitK3) or a VitC:VK3 combination on a human bladder carcinoma cell line (T24) following 1-h and 2-h vitamin treatment. T24 cells exposed to VitC alone exhibited membranous damage (blebs and endoplasmic extrusions, elongated microvilli). VitK3-treated cells displayed greater membrane damage and enucleation than those treated with VitC as well as cytoplasmic defects characteristic of cytoskeletal damage. VitC:VitK3-treated cells showed exaggerated membrane damage and an enucleation process in which the perikarya separate from the main cytoplasmic cell body by self-excision. Self-excisions continued for perikarya which contained an intact nucleus surrounded by damaged organelles. After further excisions of cytoplasm, the nuclei exhibited nucleolar segregation and chromatin decondensation followed by nuclear karryorhexis and karyolysis. This process of cell death induced by oxidative stress was named autoschizis because it showed both apoptotic and necrotic morphologic characteristics.


Assuntos
Antineoplásicos/farmacologia , Ácido Ascórbico/farmacologia , Morte Celular , Vitamina K/análogos & derivados , Adenocarcinoma/patologia , Adenocarcinoma/ultraestrutura , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Sinergismo Farmacológico , Humanos , Microscopia Eletrônica de Varredura , Fatores de Tempo , Células Tumorais Cultivadas/efeitos dos fármacos , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/ultraestrutura , Vitamina K/farmacologia , Vitamina K 3
18.
Percept Mot Skills ; 75(2): 425-6, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1408602

RESUMO

A Beckman Type RM Dynograph was used to record the eye movements of 26 professional college men, once without spectacle corrections and then with plano lenses on a trial frame, during reading equivalent print at a distance of 33 cm. Amplitudes of the return-sweep velocity on these two trials were used to calculate an equivalent form reliability coefficient. A Pearson r of 0.88 indicates that their reliability is moderately high, meaning that both the desirable as well as the undesirable reading habits are probably deeply rooted by college, and imply that any reading remediation or improvement training should be performed at some much earlier stages to be efficiently effective.


Assuntos
Atenção , Movimentos Oculares , Leitura , Adulto , Eletroculografia , Óculos , Humanos , Masculino
19.
Biomech Model Mechanobiol ; 10(3): 283-93, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20582612

RESUMO

A simplified analytical solution has been obtained for the radial and tangential displacements on the surface of a thin, hemispherical layer of porous-elastic articular cartilage firmly bonded to a rigid foundation. A static pressure distributed according to a paraboloid of revolution is applied simulating cartilage compression by a porous indenter. The solution method is in the form of an asymptotic series and uses Laplace transforms. The analytical predictions are in qualitative agreement with the behaviour of biphasic articular cartilage reported in the literature. A direct comparison with numerical simulations using commercially available Finite Element Modelling (FEM) software was also carried out for conditions relevant to natural hip joints and the results show a good quantitative agreement overall.


Assuntos
Cartilagem Articular/anatomia & histologia , Cartilagem Articular/fisiologia , Fenômenos Biomecânicos/fisiologia , Análise de Elementos Finitos , Humanos , Pressão , Reprodutibilidade dos Testes , Suporte de Carga
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