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1.
Eur J Surg Oncol ; 36(12): 1215-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20947288

RESUMO

BACKGROUND: Isolated limb infusion (ILI) for recurrent or in-transit melanoma is an accepted technique that allows high-dose chemotherapy to be delivered to an extremity with minimal systemic toxicity. Current infusion systems have relied on manual delivery of drugs and circulation of blood during the treatment. Herein, we document our initial results with an automated circuit for ILI as an alternative to the manual technique. METHODS: Patients undergoing ILI with an automated circuit for recurrent or advanced malignancy were identified. ILI was performed utilizing a Sarns 8000 roller pump attached to a Cobe 4:1 cardioplegia set with heat exchanger with a total priming volume of 80 ml. Melphalan (7.5 mg/L) and Dactinomycin (75 µg/L) doses which were corrected for ideal body weight were delivered via the infusion circuit after limb temperature reached 38 °C. RESULTS: Fourteen lower extremity infusion procedures were performed in 10 patients. Successful infusion procedures were completed in all patients using the automated circuit. Constant flow rates of 50-70 cc/minute were achievable with the automated circuit. Acute toxicity and clinical results were similar to that reported with manual delivery systems. CONCLUSION: ILI for advanced malignancy utilizing an automated circuit is feasible and safe. This automated system offers a safe and reliable alternative to the manual infusion technique.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia do Câncer por Perfusão Regional/métodos , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Dactinomicina/administração & dosagem , Feminino , Parada Cardíaca Induzida , Humanos , Extremidade Inferior , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Resultado do Tratamento
2.
Med Hypotheses ; 57(4): 476-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11601873

RESUMO

Although iron supplementation is considered beneficial for groups at risk for anemia, concern has been raised that it could be harmful during human immunodeficiency virus (HIV) infection. Studies suggest: (1) faster HIV disease progression in thalassemia major patients receiving inadequate doses of iron-chelating drug; (2) higher mortality among patients receiving iron supplementation with dapsone compared with aerosolized pentamidine for prophylaxis against Pneumocytis carinii pneumonia; (3) higher iron stores and mortality among patients with haptoglobin Hp 2-2 phenotype; and (4) shorter survival among patients with high bone marrow iron deposition. These studies largely involved men in developed countries. Among HIV-infected pregnant women in Africa with a high prevalence of iron deficiency, no relationship was found between indicators of iron status and HIV disease severity. The available data do not contraindicate the current practice of iron supplementation in developing countries where there is a high prevalence of both HIV infection and iron deficiency.


Assuntos
Suplementos Nutricionais , Infecções por HIV/patologia , Ferro/administração & dosagem , Anemia Ferropriva/complicações , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/epidemiologia , Feminino , Infecções por HIV/complicações , Humanos , Lactente , Ferro/sangue , Gravidez , Prevalência
3.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(1 Pt 2): 016208, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11461368

RESUMO

In this paper we present experimental data on the frequency domain response of a superconducting-quantum-interference-device ring (a Josephson weak link enclosed by a thick superconducting ring) coupled to a radio frequency tank circuit resonator. We show that with the ring weakly hysteretic the resonance line shape of this coupled system can display opposed fold bifurcations that appear to touch (pinch off). We demonstrate that for appropriate circuit parameters these pinch off line shapes exist as solutions of the nonlinear equations of motion for the system.

4.
J Ky Med Assoc ; 99(3): 98-103, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11268786

RESUMO

A retrospective review was done of all stereotactic breast biopsies performed at the Central Baptist Hospital Breast Center from February 1994 through December 1999. A total of 1,080 biopsies were performed in 1,026 patients, all by surgeons working independently. Masses were biopsied in 54% and calcifications in 40%. Eighteen percent of biopsies were malignant. The most common benign diagnosis was fibrocystic disease (72%), followed by fibroadenoma (19%), lymph node (2%), and papilloma (2%). The most common malignant diagnosis was invasive ductal carcinoma (40%) followed by ductal carcinoma in situ (32%) and mixed invasive and in situ ductal carcinoma (19%). A prebiopsy BI-RADS mammographic Category III was associated with a 2% incidence of malignancy; Category IV--17%; Category V--90%. Atypical ductal hyperplasia on stereotactic biopsy was upgraded to a malignant diagnosis after reexcision in 19% of the cases. The false-negative rate was 0.4% (sensitivity 99%) and the complication rate was 3%, mostly related to bleeding. Stereotactic biopsy is a safe and accurate technique for the minimally-invasive diagnosis of abnormal mammograms.


Assuntos
Biópsia/métodos , Doenças Mamárias/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Mamárias/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Mamografia , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
J Extra Corpor Technol ; 28(2): 67-70, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10160446

RESUMO

Three available methods used to determine heparin loading dose were studied to determine the most reliable method for reaching a target pre-bypass activated clotting time (ACT) of 510 seconds. One hundred and seven patients were randomly assigned to one of three treatment methods: A) 300 units/kg; B) Hemostasis Management System (HMS); C) RX/DX. Five different lots of heparin were assigned to Groups A and B, and Group C had one heparin lot. Different lots were used to account for possible variations in heparin activity. Post-skin incision ACTs, post-heparin pre-bypass ACTs, and heparin loading doses were compared. The mean and standard deviation of the post-heparin pre-bypass ACTs were used to determine which method was most reliable to obtain a desired ACT. There was no statistical difference between different heparin lots. There was no difference in the post-heparin ACTs for the three methods (A:487 +/- 135 vs. B:474 +/- 105 vs. C:474 +/- 111 sec). There was a statistically significant difference between the standard deviation for the HMS and 300 u/kg standard deviations (p < 0.05). The HMS has the smallest deviation which makes it the most reliable predictor of heparin loading doses to reach a target ACT for cardiopulmonary bypass.


Assuntos
Anticoagulantes/administração & dosagem , Coagulação Sanguínea/efeitos dos fármacos , Ponte Cardiopulmonar , Heparina/administração & dosagem , Adulto , Análise de Variância , Anticoagulantes/sangue , Estatura , Peso Corporal , Procedimentos Cirúrgicos Dermatológicos , Previsões , Hemostasia Cirúrgica , Heparina/sangue , Humanos , Reprodutibilidade dos Testes , Tempo de Coagulação do Sangue Total
6.
Nutr Cancer ; 19(2): 113-24, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8389042

RESUMO

This study examined the effect of increasing dietary vitamin D on chemically induced colon carcinogenesis. Male Fischer 344 rats were first injected with 1,2-dimethylhydrazine (200 mg/kg) and then fed one of five dietary levels of vitamin D as cholecalciferol (250, 1,000, 2,000, 4,000, and 10,000 IU/kg diet) for nine months. Dietary vitamin D3 had no effect on weight gain. Plasma 25-hydroxyvitamin D3 levels were similar for the 1,000 and 2,000 IU/kg groups but varied in a dose-related manner for the other groups. Vitamin D did not significantly alter the tumor incidence in either the distal or the proximal colon. No significant differences in the labeling index were found in either the proximal or the distal colon. Within the distal colon, the proliferative zone increased in a dose-related manner. Distribution of labeled cells within the crypt compartments was not affected by dietary vitamin D. Bone and serum minerals in general were unaffected by dietary vitamin D. This study shows that, at this level of dietary calcium, vitamin D did not affect 1,2-dimethylhydrazine-induced colon carcinogenesis.


Assuntos
Colecalciferol/farmacologia , Neoplasias do Colo/induzido quimicamente , 1,2-Dimetilidrazina , Animais , Autorradiografia , Densidade Óssea/efeitos dos fármacos , Calcifediol/sangue , Dieta , Dimetilidrazinas/toxicidade , Masculino , Ratos , Ratos Endogâmicos F344
7.
J Nutr ; 121(4): 568-77, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2007910

RESUMO

The purpose of this study was to determine if high levels of dietary calcium could inhibit the induction of colon tumors in rats injected with a single dose of 1,2-dimethylhydrazine (DMH). Rats were given a single subcutaneous injection of DMH (200 mg/kg body weight) 2 wk before they were fed purified diets containing 5% fat and four different levels of calcium (as calcium gluconate). After 8 mo, the following incidences of colon tumors (total) were seen: 0.2% Ca, 56%; 0.5% Ca [National Academy of Sciences/National Research Council (NAS/NRC) recommended level], 75%; 1.0% Ca, 61%; 2.0% Ca, 41%. Thus, rats fed calcium at levels above or below the NAS/NRC recommendation had lower tumor incidences. The total tumor incidence and the incidence of adenocarcinomas (with or without invasion) were not significantly affected by calcium, but the incidences of benign adenomatous polyps and of distal colon tumors were significantly affected. Autoradiographic examination of [3H]thymidine-treated rats revealed that the level of calcium did not significantly alter the cell kinetic indices in the distal colon. In the proximal colon, however, the 0.2% Ca group had a significantly larger proliferative zone, with significantly more labeled cells present at the bottom of the colon crypt. Mineral analysis of tibias and serum samples revealed that rats fed higher levels of calcium had lower bone Fe and serum Mg contents, but no significant trends were seen for Ca, P, Zn or Cu. Therefore, increasing or decreasing the calcium content above or below the NAS/NRC recommendation (supplemented to low fat diets) during the promotional phase of colon carcinogenesis altered the tumor incidence, but the effect was confined to the distal colon and to benign adenomatous polyps.


Assuntos
Cálcio da Dieta/farmacologia , Neoplasias do Colo/prevenção & controle , 1,2-Dimetilidrazina , Animais , Autorradiografia , Peso Corporal , Densidade Óssea , Cálcio da Dieta/farmacocinética , Carcinógenos , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/induzido quimicamente , Dimetilidrazinas , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Masculino , Ratos , Ratos Endogâmicos F344
8.
J Cancer Res Clin Oncol ; 116(4): 351-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1975253

RESUMO

The purpose of this study was to determine the effect of the dietary antioxidant vitamin E on hepatocarcinogenesis by peroxisome proliferators which, it is hypothesized, induce tumors by increased production of hydrogen peroxide or other oxygen radicals. Rats were fed diets containing the peroxisome proliferator ciprofibrate and one of three concentrations (10, 50, or 500 ppm) of alpha-tocopheryl acetate for 6 months or 21 months. The incidence of hepatic tumors and the number and volume of gamma-glutamyl-transpeptidase-positive, ATPase-negative, glucose-6-phosphatase-negative, and glucose-6-phosphatase-positive foci were quantified. No tumors or altered hepatic foci were seen at 6 months, but at 21 months the incidence of hepatic tumors and the number and volume of altered hepatic foci were increased in rats fed higher levels of vitamin E. Indices of oxidative damage--concentrations of malonaldehyde, conjugated dienes, and lipid-soluble fluorescence products--were not affected or were lower in rats fed higher amounts of vitamin E; the enhancing effect of vitamin E on the development of altered hepatic foci and hepatic tumors, therefore, was not related to the induction of cellular oxidative damage. Hepatic peroxisomal fatty acid beta-oxidation and vitamin C concentrations were not affected by vitamin E, whereas the glutathione concentration was decreased in rats fed higher amounts of vitamin E. This study shows that increasing the vitamin E content of the diet enhances ciprofibrate-induced hepatocarcinogenesis, but the mechanism of this effect is unclear.


Assuntos
Clofibrato/análogos & derivados , Ácido Clofíbrico/análogos & derivados , Neoplasias Hepáticas Experimentais/induzido quimicamente , Vitamina E/farmacologia , Adenosina Trifosfatases/análise , Animais , Ácido Clofíbrico/toxicidade , Sinergismo Farmacológico , Feminino , Ácidos Fíbricos , Glucose-6-Fosfatase/análise , Fígado/enzimologia , Neoplasias Hepáticas Experimentais/sangue , Neoplasias Hepáticas Experimentais/enzimologia , Ratos , Ratos Endogâmicos , Vitamina E/administração & dosagem , Vitamina E/sangue , gama-Glutamiltransferase/análise
9.
Nutr Cancer ; 14(3-4): 261-71, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2084622

RESUMO

The purpose of this study was to determine if the dietary antioxidant selenium could inhibit hepatocarcinogenesis induced by peroxisome proliferators, which are hypothesized to induce tumors by increased production of hydrogen peroxide or other reactive oxygen species. Rats were fed diets containing the peroxisome proliferator ciprofibrate and one of three concentrations (0.04, 0.2, or 1.0 ppm) of selenium for 6 or 21 months. The incidence of hepatic tumors and the number and volume of gamma-glutamyl transpeptidase-positive, ATPase-negative, glucose-6-phosphatase-negative, and glucose-6-phosphatase-positive foci at 21 months were lower in rats fed higher levels of selenium (no foci or tumors were seen at 6 mo). Indices of oxidative damage in the liver (thiobarbituric acid reactants, conjugated dienes, and lipid-soluble fluorescence products), however, were not decreased in rats fed the high-selenium diet. Therefore, selenium was protective against ciprofibrate-induced hepatocarcinogenesis, but not by reducing the degree of oxidative damage. The liver selenium and glutathione concentrations, and liver selenium-dependent glutathione peroxidase activity, increased as dietary selenium increased. Therefore, inhibition of carcinogenesis by selenium was correlated with increased levels of glutathione and glutathione peroxidase, but these did not inhibit the indices of oxidative damage. Peroxisomal beta-oxidation also increased with the dietary selenium content; it therefore does not appear to be a factor in the inhibition of hepatocarcinogenesis in rats fed higher levels of selenium.


Assuntos
Dieta , Neoplasias Hepáticas Experimentais/induzido quimicamente , Fígado/metabolismo , Selênio/farmacologia , Análise de Variância , Animais , Ácido Clofíbrico/análogos & derivados , Feminino , Ácidos Fíbricos , Glutationa Peroxidase/sangue , Fígado/efeitos dos fármacos , Fígado/enzimologia , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/prevenção & controle , Oxirredução , Ratos , Ratos Endogâmicos , Selênio/administração & dosagem
10.
Am J Surg Pathol ; 13(11): 985-7, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2610763
11.
Cancer Lett ; 44(2): 95-100, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2920376

RESUMO

The peroxisome proliferator ciprofibrate was examined for its ability to initiate hepatocarcinogenesis in rats. Ciprofibrate was fed in the diet at levels of 0%, 0.01% and 0.025% for 2 weeks in order to induce steady-state peroxisome proliferation. Rats were then subjected to partial hepatectomy and then maintained for 6 months on a basal diet or one containing 0.05% phenobarbital. Ciprofibrate treatment did not increase the number or volume of altered hepatic foci (putative preneoplastic lesions). However, ciprofibrate treatment increased liver weights in a dose-dependent manner in rats which did not receive phenobarbital. It is concluded that ciprofibrate-induced peroxisome proliferation is not sufficient to induce initiation, but that a permanent change is produced which results in an increased liver weight.


Assuntos
Clofibrato/análogos & derivados , Ácido Clofíbrico/análogos & derivados , Cocarcinogênese , Neoplasias Hepáticas Experimentais/induzido quimicamente , Microcorpos/efeitos dos fármacos , Animais , Dieta , Relação Dose-Resposta a Droga , Feminino , Ácidos Fíbricos , Fígado/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Fenobarbital , Ratos , Ratos Endogâmicos
12.
Prostate ; 10(3): 199-206, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3588411

RESUMO

Morphometric analysis and histologic grading were performed on case material from 26 patients. Relative nuclear roundness factor (RNRF) was calculated and correlated with clinical course in 14 patients undergoing prostatectomy for stage A or B prostatic carcinoma. The only patients with progression of disease were two with RNRF of 1.10. RNRF in cases without progression ranged from 0.98 to 1.07. Histologic grading by the methods of Gleason or the M.D. Anderson system failed to discriminate between the progressing and nonprogressing groups. However, when RNRF was measured in tumors initially diagnosed as stage C or D, four of eight were below 1.10, within the range of the nonprogressing low-stage cases. Thus, the usefulness of morphometry and RNRF may be limited to low-stage disease. It was additionally found that RNRF could not be reliably measured in needle biopsy specimens.


Assuntos
Núcleo Celular/patologia , Neoplasias da Próstata/patologia , Biópsia por Agulha , Humanos , Masculino , Estadiamento de Neoplasias
13.
Prostate ; 11(2): 171-82, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2444956

RESUMO

This study sought to identify differences in serum hormone levels between prostatic cancer (CaP) patients, benign prostatic hyperplasia (BPH) patients, and clinic controls (CC). Serum testosterone, estradiol, and prolactin values were obtained from 35 CaP, 42 BPH, and 161 CC patients attending a single medical center between January 1984 and April 1985. Relative risk estimates adjusted for age and race were calculated to compare hormone values between each case group and the CC. The distributions of hormone values and the testosterone to estradiol (T/E) ratios were grouped into thirds with the lowest third forming the reference category. The relative risk estimates for BPH in the middle and high thirds of testosterone were greater than unity (1.26 and 2.10, respectively), whereas the relative risk estimates in the middle and high thirds of estradiol were less than unity (0.63 and 0.35, respectively). For the middle and high thirds of the T/E ratio, the relative risk estimates for BPH showed statistically significant three- to fourfold increases. Modest depression of serum testosterone and estradiol was noted for CaP patients compared to CC, although the differences were not statistically significant. This depression was interpreted to be a likely result of the malignant process rather than a cause of it, whereas the development of clinically evident BPH was felt to be a biologically plausible response to an elevated T/E ratio.


Assuntos
Carcinoma/sangue , Estradiol/sangue , Prolactina/sangue , Hiperplasia Prostática/sangue , Neoplasias da Próstata/sangue , Testosterona/sangue , Fatores Etários , Idoso , Carcinoma/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/diagnóstico , Neoplasias da Próstata/diagnóstico , Fatores de Risco
14.
Prostate ; 10(3): 223-33, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2438672

RESUMO

Androgen receptor (AR) content in prostatic tissues from patients with either cancer or benign prostatic hyperplasia (BPH) is of interest from at least two standpoints: receptors may be a feature of the pathogenesis of these conditions, and they may be important to the management and prognosis of prostatic cancer patients. For these reasons, a quantitative autoradiographic assay for AR content in prostatic tissues has been developed. Application of autoradiography to rodent tissues yielded results that were highly correlated with those from biochemical assays. Thus, the autoradiographic analyses with human tissues reported in this paper were undertaken. Average AR content in 22 prostatic carcinomas was lower than that in tissues from 14 patients with BPH; the median values of the affinity index, the quantitative estimate of receptor content, were 7.0 and 12.0, respectively. For the cancer tissues, a trend of declining receptor content with advancing stage of disease appeared but was not statistically significant. No association between receptor content and degree of tumor aggressiveness as measured by Gleason score and MD Anderson score was evident. Patient age and race were not related to receptor content in either type of tissue.


Assuntos
Hiperplasia Prostática/patologia , Neoplasias da Próstata/análise , Receptores Androgênicos/análise , Idoso , Idoso de 80 Anos ou mais , Autorradiografia , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia
16.
J Urol ; 130(5): 871-3, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6355510

RESUMO

Specimens of transitional cell carcinoma of the ureter and renal pelvis from 20 patients were tested for blood group antigenicity using immunoperoxidase and specific red cell adherence methods. The results of antigen testing were correlated with tumor stage and grade as well as the subsequent clinical course of the patients. The specific red cell adherence test was negative in 80 per cent and the immunoperoxidase test was negative in 40 per cent of all tumors. Of the 4 patients with positive specific red cell adherence tests 3 had high grade (II to III), invasive tumors as did 7 of 12 with tumors that were positive by immunoperoxidase testing. Blood group antigen testing did not prove helpful in predicting the clinical course of our patients. In addition, a careful review of previously published data does not support the conclusion that blood group antigen testing is a valuable predictor of upper tract tumor aggressiveness.


Assuntos
Tipagem e Reações Cruzadas Sanguíneas , Carcinoma de Células de Transição/sangue , Neoplasias Renais/sangue , Neoplasias Ureterais/sangue , Adulto , Idoso , Antígenos de Grupos Sanguíneos/imunologia , Eritrócitos/imunologia , Humanos , Reação de Imunoaderência , Técnicas Imunoenzimáticas , Pelve Renal , Pessoa de Meia-Idade , Prognóstico
17.
J Urol ; 130(3): 499-503, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6350617

RESUMO

The specific red cell adherence test as a method to detect blood group antigen deletion in urothelial malignancy has been reported to yield approximately 40 per cent false negative results in 0 blood group patients. Our study of multiple sections of 8 normal ureters from blood group 0 patients and more than 220 specimens of transitional cell cancer taken from 48 patients reveals that the immunoperoxidase technique is more specific than the specific red cell adherence method in predicting subsequent invasion in blood group O(H) patients presenting with superficial transitional cell carcinomas (71 compared to 29 per cent) but is no more specific for tumors containing A or B antigens. However, immunoperoxidase staining does improve discernment of underlying histologic detail and, thereby, facilitates recognition of false positive antigen testing associated with squamous and adenomatous metaplasia. Areas of squamous and adenomatous metaplasia in specimens we tested were frequently antigen positive in invasive tumors. Therefore, we believe that these areas must be disregarded in determining antigen deletion in transitional cell carcinomas.


Assuntos
Sistema ABO de Grupos Sanguíneos , Carcinoma de Células de Transição/imunologia , Testes de Hemaglutinação , Isoantígenos/análise , Neoplasias da Bexiga Urinária/imunologia , Carcinoma de Células de Transição/diagnóstico , Adesão Celular , Eritrócitos/imunologia , Reações Falso-Positivas , Humanos , Técnicas Imunoenzimáticas , Invasividade Neoplásica , Ureter/imunologia , Neoplasias da Bexiga Urinária/diagnóstico
20.
J Natl Cancer Inst ; 58(2): 239-43, 1977 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-64615

RESUMO

The activities of streptovaricin complexes, streptovaricins, streptovals, and streptovarinic degradation products were elevated against RNA-directed DNA polymerases of Rauscher leukemia virus, DNA-dependent DNA polymerase of bacterial and mammalian cells, and DNA-dependent RNA polymerases of mammalian origin. The activities of streptovaricins were also listed for comparison purposes. The effects of streptovaricin complexes on viral DNA polymerases varied significantly from lot to lot, and streptovaricin complex lot 7 was the most active. All the streptovals and streptovaricin degradation products except varicinal A showed a marked improvement (twofold to tenfold) in activity against the viral enzyme over the parent streptovaricins. None of these compounds, however, displayed any significant effect on either the DNA polymerase of L1210 leukemia cells and Escherichia coli or the RNA polymerase of isolated nuclei of mouse liver. As a result of tests in these systems, some specific inhibitors of RNA-directed DNA polymerases of Rauscher leukemia virus were selected.


Assuntos
Vírus Rauscher/enzimologia , Inibidores da Transcriptase Reversa , Estreptovaricina/farmacologia , Fenômenos Químicos , Química , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , Dactinomicina/farmacologia , Técnicas In Vitro , Neoplasias/enzimologia , Inibidores da Síntese de Ácido Nucleico , Estreptovaricina/metabolismo , Relação Estrutura-Atividade
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