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1.
Acta Histochem ; 121(8): 151449, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31570207

RESUMO

AIM: To investigate clinico-pathological features of lymphoma of the lips, and review the literature. MATERIALS AND METHODS: Retrospective analysis and review of English literature, 1996-2016. RESULTS: Analysis included 23 cases, 7 new cases and 16 from literature, 12 M: 11 F, age 7-82 years. Four occurred in children, mean age 10.1; 19 in adults, mean 61.1 years. The lower lip was involved in the majority of cases (16, 69.56%). 14 (60.87%) were isolated to the lips, 8 (34.78%) were multifocal. Nine (39.13%) occurred in association with Sjogren's syndrome, of which one also had Hashimoto thyroiditis. IgG4-related disease and HIV were reported in one case each. The lip salivary glands were involved in most cases (19, 82.6%); 3 (13.6%) showed only cutaneous involvement. The typical presentation was single or multiple nodules (15, 65.21%), with surface ulceration in only two (8.69%). Constituent symptoms were absent in all cases, paresthesia was reported in one (4.34%). The majority (18, 78.26%) was extranodal marginal zone B-cell lymphoma - mucosa-associated lymphoid tissue lymphoma (EMZB-MALT), and one case each was mantle cell, NK-T cell, CD30 positive and plasmablastic lymphoma. CONCLUSION: The lips seem to have a unique pattern of non-Hodgkin lymphoma dominated by EMZB-MALT lymphoma, rarely other types. In more than half, neither Sjogren's syndrome nor other chronic inflammation was identified. Lesions tend to present as asymptomatic slowly progressing, non-ulcerated submucosal masses. Lymphoma should be considered even in the absence of constituent symptoms, as most cases showed none. Although the number of reported cases is rather small, disease course is usually prolonged and prognosis seems to be good.


Assuntos
Doença de Hashimoto , Neoplasias Labiais , Linfoma de Zona Marginal Tipo Células B , Doenças Raras , Síndrome de Sjogren , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Doença de Hashimoto/metabolismo , Doença de Hashimoto/patologia , Humanos , Neoplasias Labiais/metabolismo , Neoplasias Labiais/patologia , Linfoma de Zona Marginal Tipo Células B/metabolismo , Linfoma de Zona Marginal Tipo Células B/patologia , Masculino , Pessoa de Meia-Idade , Doenças Raras/metabolismo , Doenças Raras/patologia , Estudos Retrospectivos , Síndrome de Sjogren/metabolismo , Síndrome de Sjogren/patologia
2.
Int J Oral Maxillofac Surg ; 48(10): 1273-1278, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30871848

RESUMO

The purpose of this study was to identify the factors that impact the quality of life (QOL) scores of patients undergoing mandibulectomy. All patients with a diagnosis of an oral cavity neoplasm involving the mandible who underwent a mandibulectomy between January 1, 2000 and December 31, 2015 and completed a University of Washington QOL questionnaire (UW-QOL) were included in the study. Fifty-eight patients fulfilled all inclusion criteria and completed the UW-QOL questionnaire. Forty patients (69%) underwent a segmental mandibulectomy and 18 patients underwent a marginal mandibulectomy. Forty-eight patients (82.7%) had a free flap reconstruction. There was no significant difference in the QOL scores between patients who underwent a marginal or a segmental mandibulectomy. In contrast, patients who underwent symphysial resection reported significantly worse scores in various domains compared to patients with body or ramus segmental mandibulectomy. Patients who underwent a segmental mandibulectomy that included the symphysis had worse outcomes in chewing, recreation, health-related and social QOL domains compared to those whose mandibulectomy did not include the symphysis.


Assuntos
Osteotomia Mandibular , Neoplasias Bucais , Humanos , Mandíbula , Qualidade de Vida , Inquéritos e Questionários
3.
Blood Press ; 19(1): 11-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20001391

RESUMO

The objective of this study was to examine whether aortic stiffness, as assessed by pulse wave analysis, could reliably discriminate between normal and hypertensive pregnancies. One hundred pregnant women were studied: five with severe pre-eclampsia, 27 with gestational hypertension, 14 with chronic hypertension and 54 with normal pregnancy. Central hemodynamic parameters were obtained by an applanation tonometry and included central aortic systolic blood pressure (CSBP), central aortic diastolic blood pressure (CDBP), augmentation pressure (AP), augmentation index (AIx), AIx corrected to a heart rate of 75 (AIx@75) and time to reflection (Tr). All measures of aortic stiffness, including AP, AIx and AIx@75 were significantly higher in women with gestational hypertension and pre-eclampsia compared with normal pregnancies and women with chronic hypertension (p < 0.05 for all comparisons). There were no significant differences between normal pregnancies and women with chronic hypertension (p > 0.05 for all comparisons). Tr was significantly shorter in women with pre-eclampsia and gestational hypertension compared with normal pregnancies (p < 0.05). Aortic stiffness, as assessed by pulse wave analysis, is significantly increased in women with pre-eclampsia and gestational hypertension but not in treated women with chronic hypertension. Pulse wave analysis has a potential as a screening tool in women at high risk for pre-eclampsia. The final role of this method should be determined in prospective studies.


Assuntos
Aorta/fisiopatologia , Elasticidade , Hipertensão Induzida pela Gravidez/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Adulto , Pressão Sanguínea , Doença Crônica , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Hipertensão Induzida pela Gravidez/diagnóstico , Pré-Eclâmpsia/diagnóstico , Gravidez , Complicações na Gravidez/diagnóstico , Fluxo Pulsátil
4.
Phys Rev Lett ; 97(10): 103902, 2006 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-17025818

RESUMO

Recent studies of correlations of intensity in databases of natural images revealed a remarkable property. The two point correlations are described in terms of power law behavior, with an exponent which seems to be robust. In the present Letter we consider the statistical meaning of that result. We study many individual images of one of the databases considered. We find that the same law characterizing the correlations in the whole database governs also images randomly chosen from that database, with one essential difference. The exponent characterizing each image is specific and differs from the exponent characterizing the whole database. The distribution of single image exponents has been measured and found to exhibit a rather heavy tail. The database exponent cannot, thus, be considered as a statistical representative of a single image exponent. Possible reasons for the diversity in image exponents are discussed.

5.
Curr Pharm Des ; 7(16): 1595-614, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11562301

RESUMO

The development of drug resistance is considered to be a major cause for the failure of chemotherapy in a number of types of cancer, including ovarian, breast and lung. Most previous research has focused on approaches to reverse drug resistance once it has arisen, that is, on the use of agents which can make drug-resistant tumors more sensitive to chemotherapy. Unfortunately, this approach has thus far met with only limited clinical success. Because of the prevalence of drug resistance in cases of advanced cancer, there exists an urgent need to develop new approaches to dealing with this problem. We have hypothesized the feasibility of an alternative approach: the use of specific agents to prevent the development of resistance before it arises. Our initial studies to examine this hypothesis have focused on ovarian cancer. We have designed both in vitro and in vivo systems in which resistance develops rapidly after exposure of tumor cells or xenografts to melphalan or cisplatin. Using these systems we have shown that two selenium compounds, selenite and selenomethionine are able to prevent the induction of resistance. Furthermore, inclusion of selenite in a chemotherapeutic protocol can result in a significant enhancement of the efficacy of cisplatin in suppressing the growth of human ovarian tumor xenografts. These results have supported the idea that prevention may be a useful new approach to the problem of drug resistance in cancer chemotherapy.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Humanos
6.
Chest ; 118(6): 1724-31, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11115465

RESUMO

OBJECTIVES: This study evaluated the morbid results of prolonged intubation after coronary artery bypass grafting (CABG). METHODS: Over 30 months, 66 of 1,112 patients undergoing CABG required prolonged intubation. They were matched with 66 patients who did not require prolonged intubation. Preoperative and operative variables were evaluated to determine which would predict prolonged intubation. The postoperative courses were then compared to evaluate the effect of prolonged intubation. The study population was divided into three groups: those who underwent early extubation, but required reintubation (n = 24); those who required initial prolonged intubation, but no reintubation (n = 22); and those who required initial prolonged intubation and reintubation (n = 20). RESULTS: Univariate analysis revealed unstable angina (p = 0.037), elevated creatinine (p = 0.001), reduced FEV(1) (p = 0.019), longer cardiopulmonary bypass time (p = 0.009), and a greater positive fluid balance at 24 h (p = 0.0001) as predictors of postoperative prolonged intubation. Multivariate regression analysis revealed elevated creatinine (p = 0.011), FEV(1) (p = 0.022), and fluid balance (p = 0.001) as predictors of prolonged intubation. The study population had longer ICU and hospital stays (p = 0.0001), with more infectious complications (p = 0.0001) and higher mortality (p = 0. 001). In the subgroups of the study population, patients not requiring reintubation had shorter ICU (p = 0.001) and hospital stays (p = 0.0001), fewer infectious complications (p = 0.0001), and reduced mortality (p = 0.0001). CONCLUSIONS: Patients undergoing CABG with reduced FEV(1), renal failure, and positive fluid balance 24 h postoperatively are at risk for prolonged intubation. Prolonged intubation results in significant acute and midterm morbidity and mortality. Early extubation followed by reintubation further increases morbidity and mortality rates in these patients.


Assuntos
Ponte de Artéria Coronária , Intubação Intratraqueal , Cuidados Pós-Operatórios , Complicações Pós-Operatórias , Idoso , Ponte Cardiopulmonar , Ponte de Artéria Coronária/efeitos adversos , Creatinina/sangue , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Qualidade de Vida , Fatores de Risco , Fatores de Tempo , Equilíbrio Hidroeletrolítico
7.
Cancer Chemother Pharmacol ; 46(1): 74-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10912582

RESUMO

PURPOSE: The development of drug resistance is a major cause for the failure of chemotherapy, particularly in ovarian cancer. Most previous research has focused on approaches to reverse drug resistance once it has arisen, that is, on the use of agents which can make drug-resistant tumors more sensitive to chemotherapy. We have suggested the feasibility of an alternative approach: the use of specific agents to prevent the development of resistance. METHODS: We designed an in vivo system to assay for the ability of compounds to prevent the induction of resistance by cisplatin. In this system, mice bearing tumors (which originated from A2780 human ovarian tumor cells) were treated with a low dose (2.6 mg/kg) of cisplatin and the tumors rapidly developed resistance to subsequent cisplatin treatment. Cell lines initiated from these tumors retained the resistant phenotype even after several months in culture. RESULTS: When either selenite or selenomethionine were administered (i.p., 1.5 mg/kg) close to the time of the initial cisplatin treatment, the induction of resistance was prevented. Similar treatments with sulfite or methionine had no effect on the induction of resistance by cisplatin. Studies in cells from treated tumors have indicated that the selenium compounds may prevent the induction of resistance by preventing a cisplatin-induced increase in glutathione level. CONCLUSIONS: Selenium compounds specifically prevent the induction by cisplatin of drug resistance in human ovarian tumors in vivo.


Assuntos
Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Compostos de Selênio/uso terapêutico , Animais , Interações Medicamentosas , Resistencia a Medicamentos Antineoplásicos , Feminino , Glutationa/metabolismo , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Transplante Heterólogo , Células Tumorais Cultivadas
8.
Cancer Lett ; 136(1): 47-52, 1999 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-10211938

RESUMO

Exposure of A2780 human ovarian tumor cells to a low concentration of melphalan in vitro for 7 days resulted in the development of melphalan resistance. This resistance was not a stable characteristic of the cells since it was lost after 2 weeks in culture in the absence of drug. The melphalan-resistant cells exhibited significant cross-resistance to cisplatin but only minor cross-resistance to doxorubicin. The resistant cells had elevated levels of glutathione-S-transferase activity and mRNA. Exposure of the cells to the ethacrynic acid resulted in a decrease in enzyme activity as well as a reversal of their drug-resistant phenotype, indicating that the enzyme is involved in the resistance. When ethacrynic acid was present during the 7-day exposure of the cells to melphalan, the development of drug resistance was prevented. This system may serve as a useful preliminary step in screening for agents which can prevent the development of chemotherapy-induced drug resistance in human cancer.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ácido Etacrínico/farmacologia , Glutationa Transferase/antagonistas & inibidores , Melfalan/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/enzimologia , Antineoplásicos Alquilantes/metabolismo , Northern Blotting , Feminino , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , Melfalan/metabolismo , RNA Mensageiro , RNA Neoplásico , Células Tumorais Cultivadas
9.
Anticancer Res ; 18(4C): 3017-20, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9713502

RESUMO

Human ovarian tumors (derived from A2780 cells), growing as subcutaneous xenografts in immunodeficient mice, develop melphalan-resistant cells after a single treatment of the tumor-bearing animal with the drug [Caffrey, Zhang and Frenkel, submitted for publication]. Treatment of the animals with selenite by i.p. injection prevented the development of primary resistance to melphalan as well as cross-resistance to cisplatin. Selenite treatment also prevented the melphalan-induced increase in the cellular level of glutathione. In contrast, selenite administered s.c. or in drinking water had relatively little effect on the development of resistance. The results in this animal model suggest that selenite may be clinically useful in preventing the development of drug resistance during chemotherapy of cancer.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Melfalan/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Selenito de Sódio/farmacologia , Animais , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Interações Medicamentosas , Resistencia a Medicamentos Antineoplásicos , Feminino , Glutationa/metabolismo , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias Ovarianas/metabolismo , Transplante Heterólogo
10.
Anticancer Res ; 18(4C): 3021-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9713503

RESUMO

Human ovarian tumors from A2780 cells were grown as xenografts in immunodeficient mice, treated with a single i.p. dose of melphalan and tumor cells were removed and placed into tissue culture. The cells from the treated tumors exhibited an approximately 2-fold resistance to melphalan in vitro compared to cells taken from untreated tumors. This degree of resistance was similar to that of cells from tumors formed from melphalan-resistant A2780-ME cells. The cells from the treated tumors were also resistant to cisplatin but not to doxorubicin. They contained approximately 2-fold higher levels of glutathione than cells from the untreated tumors. Exposure of the cells to buthionine sulfoximine (a specific inhibitor of glutathione biosynthesis) eliminated the difference in glutathione levels as well as the difference in sensitivity to melphalan. When tumor-bearing animals were treated with buthionine sulfoximine in addition to melphalan the resulting tumor cells were not resistant to the drug. Resistance could also be demonstrated in the tumors themselves in vivo: the growth of previously untreated tumors was severely inhibited by a high dose of melphalan (11.7 mg/kg) administered i.p. to the animals, whereas the growth of tumors which had received prior treatment with melphalan was unaffected by the subsequent high dose. The rapid development of drug-resistant tumor cells after a single drug treatment in vivo makes this an excellent system for the investigation of the mechanisms by which resistance develops as well as for use in the screening for agents which can prevent it.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Melfalan/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/farmacologia , Antineoplásicos/farmacologia , Butionina Sulfoximina/farmacologia , Cisplatino/farmacologia , Doxorrubicina/farmacologia , Interações Medicamentosas , Resistencia a Medicamentos Antineoplásicos , Feminino , Glutationa/metabolismo , Humanos , Injeções Subcutâneas , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias Ovarianas/metabolismo , Fenótipo , Transplante Heterólogo , Células Tumorais Cultivadas
11.
Biol Trace Elem Res ; 62(3): 123-34, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9676878

RESUMO

We previously reported that exposure of HeLa cells to selenite for 2 h results in a decrease in their ability to attach to fibronectin (Yan and Frenkel, Cancer Res. 52, 5803-5807 [1992]), as well as a decrease in the level of fibronectin receptor (alpha5beta1 integrin) at the cell surface (Yan and Frenkel, Biol. Trace Element Res. 46, 79-89 [1994]). We have now found that after exposure to selenite, there was a decrease in the total cellular content of the receptor protein, as well as in the level of the mRNAs for both of the subunits. Exposure of cells to actinomycin D (an inhibitor of RNA synthesis) also resulted in a decrease in the level of these mRNAs, suggesting that the effect of selenite is the result of its known inhibitory effect on RNA synthesis (Frenkel, Toxicol. Lett. 25, 219-223 [1985]). Exposure of cells to actinomycin D for 2 h also resulted in a decrease in the ability of cells to attach to fibronectin. Furthermore, both selenite and actinomycin D caused a decrease in integrin mRNA levels and in cell attachment to fibronectin only when high-density cells were exposed to the agents. In contrast, when low-density cells were exposed,neither agent had any detectable effect on mRNA levels or on cell attachment. These results have suggested the following scheme for the mechanism of the inhibition of cell attachment by selenite: After exposure to selenite for 2 h, there is a significant inhibition of cellular RNA synthesis, which results in a general decrease in the cellular level of those mRNAs with relatively short half-lives, including in particular those of the fibronectin receptor. This leads to a decrease in the intracellular level of the receptor protein and, consequently, in its level at the cell surface, which in turn causes a decrease in the rate of cell attachment to fibronectin.


Assuntos
Adesão Celular/fisiologia , RNA Mensageiro/metabolismo , Receptores de Fibronectina/genética , Selenito de Sódio/farmacologia , Northern Blotting , Western Blotting , Adesão Celular/efeitos dos fármacos , Dactinomicina/farmacologia , Células HeLa , Humanos , Cinética , Receptores de Fibronectina/biossíntese
12.
Biol Trace Elem Res ; 65(3): 187-95, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9892492

RESUMO

Exposure of A2780 human ovarian tumor cells to a low concentration of melphalan in vitro for 7 d results in the development of melphalan resistance, which is dependent on elevated cellular levels of glutathione and glutathione S-transferase. The inclusion of selenite (at concentrations as low as 0.2 microM) during the exposure to melphalan completely prevented the development of resistance. Selenite did not prevent the melphalan-induced increase in glutathione, but it did prevent the increase in the activity of glutathione S-transferase. It also prevented the increase in the expression of the glutathione S-transferase gene, suggesting that this may be the mechanism by which it prevents the development of melphalan resistance. The results of this in vitro study suggest that selenite may prove to be useful in preventing the development of drug resistance in vivo.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Melfalan/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Selenito de Sódio/farmacologia , Northern Blotting , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Resistencia a Medicamentos Antineoplásicos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glutationa Transferase/efeitos dos fármacos , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , RNA Mensageiro/análise , Células Tumorais Cultivadas/efeitos dos fármacos
13.
Cancer Lett ; 121(2): 177-80, 1997 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-9570356

RESUMO

Previous studies have demonstrated that melphalan-resistant human ovarian tumor cells exhibit a higher degree of sensitivity to the cytotoxic effects of selenite in vitro than comparable drug-sensitive cells (P.B. Caffrey, G.D. Frenkel, Selenite cytotoxicity in drug resistant and non-resistant human ovarian tumor cells, Cancer Res. 52 (1992) 4812-4816; P.B. Caffrey, G.D. Frenkel, The development of drug resistance by tumor cells in vitro is accompanied by the development of sensitivity to selenite, Cancer Lett. 81 (1994) 59-65). We have now examined the sensitivity of drug-resistant tumors to selenite in vivo. A2780 human ovarian tumor cells, or their melphalan-resistant derivative (A2780ME) cells were injected subcutaneously into nude mice and the resulting tumors were found to be melphalan-sensitive and -resistant, respectively, in vivo. Treatment with selenite (2 mg/kg Se s.c.), which had no overt toxic effect on the animals, resulted in a significant decrease in the rate of growth of the melphalan-resistant tumors, but not on the rate of growth of the drug-sensitive tumors. Thus, melphalan-resistant ovarian tumors are also more sensitive to selenite treatment in vivo.


Assuntos
Anticarcinógenos/uso terapêutico , Antineoplásicos Alquilantes/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Melfalan/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Selenito de Sódio/uso terapêutico , Animais , Feminino , Humanos , Camundongos , Camundongos Nus , Células Tumorais Cultivadas
14.
Genetika ; 31(1): 139-43, 1995 Jan.
Artigo em Russo | MEDLINE | ID: mdl-7896124

RESUMO

A new information technology, the information-logical approach (ILA), which is based on information theory methods and the fuzzy sets theory, is considered. This method can be applied for the majority of biological and ecological studies, and in genetics. In breeding and genetic studies, ILA can be used as a basis for the development of methods that will allow one to take into account ecological, geographic, climatic, and other peculiarities of trait expression that influence productivity. Application of ILA also opens new prospects for analyzing results of genetic and ecological monitoring (e.g., post-Chernobyl' monitoring) to predict further behavior of the systems studied. This paper presents a general outline of information analysis, describes a block of one-factor analysis, which was implemented on a personal computer and has a user-friendly interface, and also presents several examples concerning application of ILA to specific genetic systems.


Assuntos
Técnicas Genéticas , Monitoramento Ambiental , Lógica , Modelos Genéticos
15.
Biol Trace Elem Res ; 46(1-2): 79-89, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7534098

RESUMO

Incubation of cells with selenite, under conditions in which there is no effect on cell viability, results in a decrease in the rate of their subsequent attachment to extracellular matrix proteins such as fibronectin (1). The attachment was inhibited by a pentapeptide containing the RGD sequence and by antibody against the cellular fibronectin receptor (alpha 5 beta 1 integrin), indicating that it is receptor-mediated. To investigate whether exposure to selenite has an effect on fibronectin receptors, we assayed for their presence on the cell surface by measuring the ability of cells to attach to a surface that had been coated with antibodies to the receptor. Brief exposure of cells to low concentrations of selenite resulted in a significant decrease in their ability to attach to monoclonal antibodies against the alpha 5 or beta 1 subunits of the fibronectin receptor, as well as to polyclonal antibodies against the complete receptor. This indicates that exposure to selenite results in a decrease in receptors that are present at the cell surface. Exposure of the cells to selenate, selenocystine or selenomethionine did not result in a significant decrease in cell surface receptors. Preincubation of the cells with selenite was required for the effect, indicating that selenite does not directly interfere with receptor structure or function.


Assuntos
Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Fibronectina/efeitos dos fármacos , Selenito de Sódio/farmacologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Adesão Celular/efeitos dos fármacos , Epitopos/efeitos dos fármacos , Epitopos/metabolismo , Fibronectinas/metabolismo , Células HeLa , Humanos , Proteínas de Membrana/análise , Receptores de Superfície Celular/metabolismo , Receptores de Fibronectina/imunologia , Receptores de Fibronectina/metabolismo
16.
J Inorg Biochem ; 55(2): 113-21, 1994 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-7519656

RESUMO

The relationship between intracellular sulfhydryl(SH) compounds and the kinetics of the inhibitory effect of selenite on cellular nucleic acid synthesis has been examined. In A549 cells, with a relatively high SH level, exposure to low concentrations of selenite caused inhibition even after short exposure times. In contrast, in VA cells, with a relatively low level of SH compounds, selenite had no significant effect at short exposure times, but inhibited significantly with longer exposures. Selenodicysteine, the product of the reaction of selenite with cysteine (an important intracellular SH compound), inhibited synthesis in both cell types at short exposure times. Exposure of cells to diethylmaleate, which decreased the level of intracellular SH compounds, reduced the inhibitory effect of a short exposure to selenite but did not affect a long exposure. These results indicate that the reaction of selenite with intracellular SH compounds may be a determining factor in the kinetics of its inhibitory effect on cellular DNA and RNA synthesis.


Assuntos
DNA/biossíntese , RNA/biossíntese , Selenito de Sódio/farmacologia , Adenocarcinoma , Linhagem Celular Transformada , DNA/antagonistas & inibidores , Embrião de Mamíferos , Embrião não Mamífero , Cinética , Pulmão , Neoplasias Pulmonares , Maleatos/farmacologia , RNA/antagonistas & inibidores , Compostos de Sulfidrila/metabolismo , Células Tumorais Cultivadas
17.
Cancer Lett ; 81(1): 59-65, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-8019989

RESUMO

The effects of selenite on cell viability and proliferation in a line of drug-sensitive human ovarian tumor (A2780) cells were compared with its effects on a melphalan-resistant derivative of these cells (A2780-ME) which had been developed in vitro (Hamilton et al. (1985) Biochemical Pharmacol., 34, 2583-2586). With the A2780-ME cells there was a 50% decrease in the number of viable cells (i.e. which exclude Trypan Blue dye) after exposure to less than 100 microM selenite for 6 h. In contrast, exposure to more than 300 microM selenite was required to achieve the same effect in the parent line. Similarly, exposure to 10 microM selenite resulted in a 50% decrease in A2780-ME cell proliferation, whereas this treatment had only a small inhibitory effect on proliferation of the parent cells. Thus, the development of melphalan resistance in vitro was accompanied by the development of selenite sensitivity. Pre-exposure of the two cell types to buthionine sulfoximine eliminated the difference in their intracellular glutathione levels, as well as most of their differential sensitivity to selenite. Furthermore, the two cell types did not exhibit a difference in sensitivity to selenodiglutathione, the product of the reaction of selenite with glutathione. Thus, the increase in intracellular glutathione, which has been shown to be responsible for the development of drug resistance in these cells is also responsible for the development of selenite sensitivity.


Assuntos
Resistência a Medicamentos , Neoplasias Ovarianas/tratamento farmacológico , Selenito de Sódio/farmacologia , Divisão Celular/efeitos dos fármacos , Feminino , Glutationa/análogos & derivados , Glutationa/análise , Glutationa/farmacologia , Humanos , Melfalan/farmacologia , Compostos Organosselênicos/farmacologia , Neoplasias Ovarianas/patologia , Células Tumorais Cultivadas
18.
Cancer Lett ; 78(1-3): 195-9, 1994 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8180964

RESUMO

Pre-exposure of HeLa or NIH:OVCAR-3 cells to selenite resulted in a dose-dependent decrease in the ability of the cells to invade a layer of Matrigel, a reconstituted basement membrane preparation. In contrast, selenate, selenomethionine and sulfite had no significant effect on cell invasiveness. Exposure of HeLa cells to selenite also resulted in a decrease in two of the necessary steps of the invasion process, attachment and mobility; in contrast, exposure of OVCAR cells decreased attachment but not mobility. There was an apparent correlation between the processes that are affected by selenite and those that involve the cellular fibronectin receptor (alpha 5 beta 1 integrin).


Assuntos
Invasividade Neoplásica , Selenito de Sódio/farmacologia , Células 3T3 , Animais , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Técnicas In Vitro , Camundongos , Receptores de Fibronectina/fisiologia , Selenometionina/farmacologia , Sulfitos/farmacologia
19.
J Clin Pharmacol ; 34(3): 225-30, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8021330

RESUMO

The analgesic efficacy of single oral doses of drinkable diclofenac dispersible 50 mg was compared with that of ibuprofen 400 mg and placebo in a randomized, double-blind, parallel-group trial in 257 adult patients (245 valid for efficacy) with severe postoperative pain after extraction of an impacted lower third molar. In this study, pain intensity (on a 100-mm visual analog scale) and pain relief from baseline (using a five-point verbal rating scale) were assessed serially during an observation period of 6 hours. Intake of rescue analgesic was permitted in case of insufficient therapeutic effect; however at least 1 hour should have elapsed after test drug consumption. On the main efficacy variable, namely, reduction in the pain intensity score, both diclofenac dispersible (n = 83) and ibuprofen (n = 80) were statistically significantly (P < .01) superior to placebo (n = 82) starting at 20 and 40 minutes, respectively, after drug intake. The active medications were also significantly (P < .01) better than placebo for the secondary efficacy parameters viz. summed pain relief scores over 6 hours (TOTPAR-6); frequency of remedication with a rescue analgesic in the three treatment groups (diclofenac, 24%; ibuprofen, 28%; placebo, 65%); mean time to remedication; and global evaluation. All the treatments were well tolerated. Thus assay sensitivity of this trial (ibuprofen significantly better than placebo) has been demonstrated; in addition, diclofenac as a dispersible formulation has been shown to be an effective analgesic for the treatment of post-surgical dental pain.


Assuntos
Diclofenaco/uso terapêutico , Ibuprofeno/uso terapêutico , Dente Serotino/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Extração Dentária , Dente Impactado/cirurgia , Administração Oral , Adulto , Idoso , Diclofenaco/administração & dosagem , Diclofenaco/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Ibuprofeno/administração & dosagem , Ibuprofeno/efeitos adversos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Extração Dentária/efeitos adversos
20.
Biol Trace Elem Res ; 40(2): 181-7, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7514023

RESUMO

Selenite has been shown to undergo intracellular metabolism that results in its conversion to other low molecular weight Se-containing species and also to its incorporation into a selenocysteine residue in selenoprotein. In order to investigate whether the incorporation into protein is required for the cytotoxic effects of selenite, we have examined whether inhibition of protein synthesis prevents the inhibitory effect of selenite on the ability of cells to form colonies or to synthesize RNA. We have found that treatment of HeLa cells with cycloheximide inhibited protein synthesis by > 90% but had no effect on the inhibitory effect of selenite on cell colony formation or RNA synthesis. Since protein synthesis is not necessary for these cytotoxic effects of selenite they are unlikely to result from an increase in the synthesis of selenoproteins.


Assuntos
Células Clonais/efeitos dos fármacos , Biossíntese de Proteínas , RNA/biossíntese , Selenito de Sódio/farmacologia , Células Clonais/citologia , Cicloeximida/farmacologia , DNA/biossíntese , Células HeLa , Humanos , Peso Molecular , Selenocisteína/metabolismo
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