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1.
Clin Ter ; 173(6): 551-556, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36373454

RESUMO

Introduction: Prisoners are at risk of developing vitamin D deficiency due to their lacking exposure to sunlight. So far, there are no published studies evaluating blood levels of vitamin D in relation to the health status of inmates and the quality of the Italian prison system. Aim: To investigate vitamin D status and its determinants in a cohort of prisoners. Subject and Methods: One hundred and seventy-two (172) pri-son inmates (males, n=159, age 47± 11.3 years; females, n=13, age 43.91±12.18 years) of three penitentiaries in the province of Salerno. Vitamin D deficiency, insufficiency and sufficiency were respectively defined as a 25(OH)D level <20 ng/mL; from 20 to 30 ng/mL, >30 ng/mL. Results: In our group, Vitamin D deficiency occurs in 77.32% of the prisoners with 32.55% of the cases having severe insufficiency. Prisoners with higher BMI show lower circulating vitamin D levels (p<0.001). No significant relationship was found with the duration of detention (Pearson R: 0.01). Conclusion: In this cohort of inmates the vitamin D status is determined by BMI, but not by the duration of the detention.


Assuntos
Prisioneiros , Deficiência de Vitamina D , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Prisões , Vitamina D , Itália/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitaminas , Prevalência
4.
Nanotechnology ; 22(18): 185305, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21427473

RESUMO

Ordered arrays of nanoelectrodes for electrochemical use are prepared by electron beam lithography (EBL) using polycarbonate as a novel e-beam resist. The nanoelectrodes are fabricated by patterning arrays of holes in a thin film of polycarbonate spin-coated on a gold layer on Si/Si(3)N(4) substrate. Experimental parameters for the successful use of polycarbonate as high resolution EBL resist are optimized. The holes can be filled partially or completely by electrochemical deposition of gold. This enables the preparation of arrays of nanoelectrodes with different recession degree and geometrical characteristics. The polycarbonate is kept on-site and used as the insulator that separates the nanoelectrodes. The obtained nanoelectrode arrays (NEAs) exhibit steady state current controlled by pure radial diffusion in cyclic voltammetry for scan rates up to approximately 50 mV s( - 1). Electrochemical results showed satisfactory agreement between experimental voltammograms and suitable theoretical models. Finally, the peculiarities of NEAs versus ensembles of nanoelectrodes, obtained by membrane template synthesis, are critically evaluated.

5.
J Endocrinol Invest ; 32(5): 390-4, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19794285

RESUMO

INTRODUCTION: Chronic mild endogenous glucocorticoid excess has been shown to cause bone loss and to increase fracture risk in both post-menopausal and premenopausal women. Currently, it is unclear if patients with subclinical Cushing's syndrome (SCS) with osteoporosis or osteopenia may benefit from antiresorptive treatment and the type of therapy to be given. OBJECTIVE: This pilot randomized study was aimed at evaluating the effects of 12-month im administration of clodronate (100 mg every week) on vertebral and femoral bone mineral density (BMD), bone turnover markers and on subjective pain in premenopausal women with SCS due to adrenal incidentalomas. METHODS: Forty-six women (age, 43.1+/-7.7 yr) with SCS due to adrenal incidentaloma and osteoporosis/osteopenia were randomized to receive clodronate plus supplement of Calcium (500 mg daily) and Vitamin D3 (800 mg daily) (group 1, no.=23) or supplements only (group 2, no.=23). Both groups were similar in terms of age, body mass index, cortisol levels, BMD values, and bone turnover markers. All of the women were re-evaluated after 12 months. RESULTS: After 12 months of treatment, in group 1, a significant increase in lumbar BMD occurred (p=0.04), while bone turnover markers decreased by about one third (p<0.05). In group 2, bone turnover markers did not change and BMD values slightly decreased (p=ns). The differences in bone turnover markers and in lumbar BMD between the two groups were significant (p<0.05, all). No new vertebral fracture occurred in group 1, while in group 2 the spine radiographies revealed 2 new fractures and a worsening of two pre-existent fractures. An improvement in subjective back pain, assessed by visual analogue scale pain score was observed in group 1 (from 4.3+/-2.7 to 2.9+/-2.0; p<0.05) but not in group 2 (from 4.4+/-3.1 to 4.2+/-3.4; p=ns). No significant changes occurred in cortisol secretion or clinical picture of the SCS during the study. CONCLUSIONS: Intramuscular administration of clodronate effectively increased lumbar BMD values, preserved bone mass at the femoral neck, stabilized vertebral fracture index, and decreased subjective back pain in pre-menopausal women with SCS. Since the untreated group continued to lose bone, antiresorptive treatment should be considered in patients with SCS, according to the prevision of surgical treatment, prevalent fractures, BMD values, age, concomitant morbidities, and desire for pregnancy.


Assuntos
Reabsorção Óssea/prevenção & controle , Ácido Clodrônico/administração & dosagem , Síndrome de Cushing/tratamento farmacológico , Fraturas da Coluna Vertebral/prevenção & controle , Adenoma/complicações , Adenoma/tratamento farmacológico , Administração Oral , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Adulto , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/efeitos adversos , Reabsorção Óssea/etiologia , Cálcio/administração & dosagem , Colecalciferol/administração & dosagem , Ácido Clodrônico/efeitos adversos , Síndrome de Cushing/complicações , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Fraturas da Coluna Vertebral/etiologia
6.
J Ethnopharmacol ; 115(2): 271-5, 2008 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-18023308

RESUMO

Pteleopsis suberosa Engl. et Diels (Combretaceae) is a tree distributed in many African countries. The decoction from the stem bark is orally administered for the treatment of gastric ulcers in traditional medicine. Previous pharmacological studies reported the anti-ulcer activity of extracts from P. suberosa stem bark. In the present study, the anti-ulcer and anti-inflammatory effects of the n-butanol fraction (RBuOH) obtained from a methanol extract of P. suberosa bark were investigated on ethanol-induced gastric ulcers in rats and carrageenan-induced paw oedema in mice. Misoprostol (0.50 mg/kg, p.o.) and indomethacin (8.00 mg/kg, p.o.) were used as positive controls for anti-ulcer and anti-inflammatory activities, respectively. Results showed that RBuOH treatment significantly reduced the incidence of gastric lesions (50 mg/kg, P<0.05; 100 and 200 mg/kg, P<0.01) and restored the decreased levels of total sulfhydryl groups (T-SH) and non-protein sulfhydryl groups (NP-SH) (50, 100 mg/kg, P<0.05; 200 mg/kg, P<0.01) in the stomach homogenate. Moreover, RBuOH treatment attenuated MDA levels as index of lipid peroxidation in gastric mucosa. Administration of RBuOH at the same dosage (50, 100 and 200 mg/kg) reduced significantly (P<0.01) carrageenan-induced paw oedema in dose-dependent manner (from 42.81% to 87.81% inhibition, 5h after carrageenan injection). The anti-inflammatory effect of RBuOH at 200 mg/kg was comparable with that of indomethacin. Finally, RBuOH proved to possess elevated free radical scavenger capacity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay (IC(50) 23.48 microg/ml) which may contribute to the observed anti-ulcer and anti-inflammatory activities.


Assuntos
Anti-Inflamatórios/farmacologia , Antiulcerosos/farmacologia , Antioxidantes/farmacologia , Combretaceae/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Antiulcerosos/administração & dosagem , Antiulcerosos/isolamento & purificação , Antioxidantes/administração & dosagem , Antioxidantes/isolamento & purificação , Relação Dose-Resposta a Droga , Radicais Livres/metabolismo , Indometacina/farmacologia , Inflamação/tratamento farmacológico , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Misoprostol/farmacologia , Casca de Planta/química , Extratos Vegetais/administração & dosagem , Ratos , Ratos Wistar , Úlcera Gástrica/tratamento farmacológico , Compostos de Sulfidrila
7.
J Endocrinol Invest ; 31(11): 956-65, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19169050

RESUMO

No head-to-head comparisons are available to analyze the efficacy of octreotide (LAR) and lanreotide (LAN) as first-line treatment of acromegaly.We compared the efficacy of these two drugs in 54 newly diagnosed patients (21 women, 33 men), 27 treated with LAR (10-30 mg every 28 days) and 27 with LAN (60-90 mg/28 days), for 12 months. Each LAR-treated patient was matched with one LAN-treated patient as for GH levels, sex, and age (+/-5 yr). Outcome measures were GH and IGF-I levels and tumor shrinkage and secondarily classical cardiovascular risk factors (total/HDL-cholesterol ratio, glucose tolerance), blood pressure and drug tolerability. In LAR- and in LAN-treated patients, respectively: GH and IGF-I were controlled in 21 (77.7%) and in 16 patients (59.3%; p=0.26); tumor shrinkage was absent (<25%) in 4 and 5 patients (p=1), mild (25.1-50%) in 9 and 12 (p=0.57), moderate (50.1-75%) in 10 and 6 (p=0.37) and notable (>75%) in 4 and 4 patients (p=1). The total/HDL-cholesterol ratio and insulin levels significantly decreased while glucose levels significantly increased in both groups. None of the patients with normal glucose tolerance at diagnosis developed diabetes mellitus. Side effects were mostly at the gastrointestinal level and were similar with both drugs. In conclusion, newly diagnosed patients with acromegaly treated with LAR and LAN have no significantly different prevalence of disease control, tumor shrinkage, improvement of cardiovascular risk markers and side effects. Therefore, both drugs can be safely employed as first-line therapy of acromegaly.


Assuntos
Acromegalia/tratamento farmacológico , Octreotida/uso terapêutico , Peptídeos Cíclicos/uso terapêutico , Somatostatina/análogos & derivados , Acromegalia/sangue , Acromegalia/patologia , Adulto , Idoso , Feminino , Hormônio do Crescimento Humano/sangue , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Somatostatina/uso terapêutico
8.
J Endocrinol Invest ; 30(6): 497-506, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17646725

RESUMO

This analytical, observational, retrospective, case-control study was designed to describe clinical presentation, biochemical disease severity, presence, and severity of metabolic and cardiovascular complications in patients diagnosed as having acromegaly at 60 yr or older (no.=57) as compared to sex- and age-matched healthy controls. Patients and controls underwent a complete endocrine, metabolic, and cardiovascular check-up. The age at diagnosis was equally distributed between 60 to 75 yr while only a minority of the patients (5.3%) was diagnosed after 75 yr. Median GH and IGF-I levels were 15 microg/l and 557 microg/l. The prevalence of microadenomas, enclosed macroadenomas, and extrasellar/invasive macroadenomas was 30%, 49%, and 21%, respectively. All patients had joint complaints and goiter (euthyroid in 65% and pre-toxic/toxic in 35%), 82% had hypertension, 58% diabetes and 54% had both. As compared to controls, a higher number of patients were receiving treatment with anti-arrhythmiacs (p=0.033), anti-aggregants (p=0.013), levothyroxine (p=0.015), and metformin (p=0.022). Nevertheless, the patients had higher systolic and diastolic blood pressure, heart rate, left ventricular mass index, lipids, glucose and insulin levels as well as percent function of beta cells than controls. In conclusion, the high prevalence of systemic complications makes elderly acromegalics more susceptible than controls to cardiovascular events. We suggest that an accurate clinical check-up and, possibly, a more aggressive treatment of hypertension and diabetes are required in elderly acromegalics.


Assuntos
Acromegalia , Cardiomiopatias , Acromegalia/complicações , Acromegalia/metabolismo , Acromegalia/fisiopatologia , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Cardiomiopatias/fisiopatologia , Fenômenos Fisiológicos Cardiovasculares , Estudos de Casos e Controles , Feminino , Glucose/metabolismo , Hormônio do Crescimento Humano/sangue , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
9.
J Endocrinol Invest ; 28(11 Suppl International): 58-66, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16625847

RESUMO

Currently available medical treatment of acromegaly includes dopamine agonists, slow release formulation of somatostatin analogues and pegvisomant, a GH-receptor antagonist. Dopamine agonists are well tolerated, not expensive but poorly effective. Somatostatin analogues are highly effective in 60-70% of patients based on the receptor profile of individual tumors. Pegvisomant is reported to normalize IGF-I levels in nearly the totality of the patients, but is devoted of tumor shrinking effect. In a preliminary study in patients with acromegaly, a new somatostatin analogue with affinity to four of the five somatostatin receptors (SOM230) was shown to be similarly effective as octreotide in some patients and more effective than octreotide in other patients. Moreover, new molecules with selective activity on the somatostatin receptor type 2, or 5, or 1 have been reported in vitro to strongly suppress GH secretion. Other new promising alternatives are the chimeric compounds with both somatostatin receptor and dopamine receptor binding. These drugs have been also shown to possess strong GH-inhibitory activity in primary cultures from GH-secreting adenomas. These drugs are the future perspectives in the treatment of patients with GH-secreting or GH/PRL-secreting tumors.


Assuntos
Acromegalia/tratamento farmacológico , Adenoma/tratamento farmacológico , Adenoma/patologia , Adulto , Animais , Preparações de Ação Retardada , Agonistas de Dopamina/uso terapêutico , Feminino , Hormônio do Crescimento Humano/análogos & derivados , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Fator de Crescimento Insulin-Like I/análise , Masculino , Pessoa de Meia-Idade , Octreotida/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/patologia , Receptores de Somatostatina/agonistas , Receptores de Somatostatina/efeitos dos fármacos , Receptores de Somatostatina/metabolismo , Receptores da Somatotropina/antagonistas & inibidores , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico
10.
G Ital Nefrol ; 19(1): 74-8, 2002.
Artigo em Italiano | MEDLINE | ID: mdl-12165949

RESUMO

BACKGROUND: Polyoma virus (PV) is a double-stranded DNA virus, member of the Papovaviridae family. BKV and JCV are the most studied in human pathology, whereas simian virus 40 (SV40) is pathogenic in the monkey and has been implicated in human carcinogenesis. PV is associated with renal and urinary tract pathology. The initial infection by PV occurs in childhood, probably by airways, and is usually asymptomatic. Subsequently, it remains latent in kidneys, tonsils and CNS and may reactivate in concomitance with significant T-cell dysfunction. Infection in immunocompromised patients can be clinically relevant. However, asymptomatic viruria may be detected in 0.3 % of individuals without a known history of immunodeficiency. CASE REPORT: We describe the case of a male patient, aged 31, admitted to our Unit for arterial hypertension and urinary abnormalities. He had a history of hemorrhagic cystitis in 1996 and persistent microscopic hematuria thereafter. Renal function was normal, arterial pressure well controlled with an ACE-inhibitor; urine culture was negative and most of the immunologic and rheumatologic tests were normal, with the exception of slightly reduced levels of C3 and an inverted CD4/CD8 ratio. Serology for HCV, HBV, HIV and screening for tumor markers were negative. Renal ultrasonography displayed an increased reflectivity, as seen in medical nephropathies; no nephrolithiasis was found. Urinary cytology showed "decoy cells", as typically found in PV infection, whose presence was confirmed by n-PCR. Diagnosis at discharge from the hospital was primary arterial hypertension and urinary JCV infection. Currently, no treatment of proven efficacy against PV is available. CONCLUSIONS: We think that there is an increasing amount of evidence to include screening for PV in the diagnosis of urinary tract abnormalities of unknown origin, even in apparently immunocompetent patients. Urinary cytology, in experienced hands, may be a useful and relatively inexpensive first step diagnostic tool.


Assuntos
Vírus JC/isolamento & purificação , Infecções por Polyomavirus/diagnóstico , Doenças Urológicas/etiologia , Adulto , Relação CD4-CD8 , Cistite/etiologia , Hematúria/etiologia , Humanos , Hipertensão/complicações , Imunocompetência , Masculino , Reação em Cadeia da Polimerase , Infecções por Polyomavirus/complicações , Proteinúria/etiologia , Urina/citologia , Urina/virologia , Doenças Urológicas/virologia , Ativação Viral , Latência Viral
11.
Psyche (São Paulo) ; 4(5): 157-182, dez. 2000.
Artigo em Português | Index Psicologia - Periódicos | ID: psi-19379

RESUMO

A lei, quando imposta pela força bruta ou simbólica gera a submissão e a exclusão. As autoras investigam o mecanismo de construção de leis e regras portadoras da violência através de duas vertentes: a visibilidade e a invisibilidade das estratégias de dominação. A psicanálise, ao pensar as relações que se estabelecem entre o sujeito e o seu objeto, a realidade psíquica e a realidade externa, a partir de uma racionalidade não dicotômica, instaura uma ética que afirma o compartilhamento e o compromisso do sujeito com o outro alteritário(AU)


Assuntos
Violência , Psicanálise , Estado , Ética
12.
Psyche (Säo Paulo) ; 4(5): 157-182, dez. 2000.
Artigo em Português | LILACS | ID: lil-410144

RESUMO

A lei, quando imposta pela força bruta ou simbólica gera a submissão e a exclusão. As autoras investigam o mecanismo de construção de leis e regras portadoras da violência através de duas vertentes: a visibilidade e a invisibilidade das estratégias de dominação. A psicanálise, ao pensar as relações que se estabelecem entre o sujeito e o seu objeto, a realidade psíquica e a realidade externa, a partir de uma racionalidade não dicotômica, instaura uma ética que afirma o compartilhamento e o compromisso do sujeito com o outro alteritário


Assuntos
Ética , Psicanálise , Estado , Violência
13.
J Nutr ; 130(5): 1303-8, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10801934

RESUMO

The 4,4'-diketo-beta-carotene, canthaxanthin, alters tocopherol status when fed to Balb/c mice, suggesting an involvement of carotenoids in the modulation of oxidative stress in vivo. We investigated further the modifications induced by an oral administration of canthaxanthin on lipid peroxidation, antioxidant enzymes and iron status in liver of Balb/c mice. Female 6-wk-old Balb/c mice were randomly divided into two groups (n = 10/group). The control group (C) received olive oil alone (vehicle) and the canthaxanthin-treated group (Cx) received canthaxanthin at a dose of 14 microg/(g body wt.d). The 15-d canthaxanthin treatment resulted in carotenoid incorporation but did not modify lipid peroxidation as measured by endogenous production of malondialdehyde (MDA). However, glutathione peroxidase activity was 35% lower (P<0.01) and catalase (59%, P<0.005) and manganese superoxide dismutase (MnSOD) (28%, P<0.05) activities were higher in canthaxanthin-treated mice than in controls. Moreover, carotenoid feeding caused a significant (P<0.05) overexpression of the MnSOD gene; mRNA levels of the enzyme were greater in treated mice than in controls. Concomitantly, a 27% (P<0.05) greater iron concentration was found in liver from canthaxanthin-treated mice compared with controls. These findings support the hypothesis that canthaxanthin alters the protective ability of tissues against oxidative stress in vivo.


Assuntos
Antioxidantes/farmacologia , Cantaxantina/farmacologia , Fígado/efeitos dos fármacos , Administração Oral , Animais , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Cantaxantina/administração & dosagem , Cantaxantina/metabolismo , Feminino , Glutationa Peroxidase/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/enzimologia , Camundongos , Camundongos Endogâmicos BALB C , Tamanho do Órgão/efeitos dos fármacos , Superóxido Dismutase/metabolismo
14.
Alcohol Alcohol ; 35(2): 159-63, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10787391

RESUMO

In order to investigate the pathogenic mechanism responsible for liver injury associated with chronic alcoholism, we studied the effects of different dietary vitamin E levels in chronically ethanol (EtOH)-fed rats on the activity and mRNA regulation of the manganese superoxide dismutase (MnSOD) enzyme. Evidence is accumulating that intermediates of oxygen reduction may in fact be associated with the development of alcoholic liver disease. Since low vitamin E liver content seems to potentiate EtOH-linked oxidative stress, we studied the effect of EtOH treatment in livers from rats fed a diet deficient or supplemented with vitamin E. Chronic EtOH feeding enhanced hepatic consumption of vitamin E in both groups of EtOH-treated animals, irrespectively of the vitamin E level of the basal diet and the effect was observed in both the microsomal and mitochondrial fractions. Both EtOH-fed groups exhibited increased MnSOD gene expression, while the enzyme activity was enhanced only in the vitamin E-deprived group of EtOH-treated animals. The significant increase in manganese liver content found only in this last group could explain the rise of enzyme activity. In fact, in the absence of a parallel increase of the prosthetic ion manganese, MnSOD mRNA induction was not accompanied by a higher enzymatic activity. These findings support the role of oxidative alteration in the EtOH-induced chronic hepatotoxicity in which MnSOD response might represent a primary defence mechanism against the damaging effect of oxygen radical species.


Assuntos
Alcoolismo , Modelos Animais de Doenças , Etanol/farmacologia , Alimentos Formulados , Superóxido Dismutase/efeitos dos fármacos , Deficiência de Vitamina E/diagnóstico , Vitamina E/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Doença Crônica , Masculino , RNA Mensageiro/efeitos dos fármacos , Ratos , Ratos Wistar
15.
Tempo psicanál ; 32: 9-35, 2000.
Artigo em Português | Index Psicologia - Periódicos | ID: psi-23906

RESUMO

A clínica psicanalítica em comunidades apresenta-se como um campo novo de trabalho e pesquisa. As autoras relatam uma experiência de trabalho clínico e psicanalítico realizada num Posto de Saúde comunitário, pretendendo - através deste relato - apresentar uma proposta diversa dos modelos anteriormente constituidos(AU)


Assuntos
Humanos , Masculino , Feminino , Psicanálise , Serviços de Saúde Comunitária
16.
Tempo psicanál ; 32: 9-35, 2000.
Artigo em Português | LILACS | ID: lil-477460

RESUMO

A clínica psicanalítica em comunidades apresenta-se como um campo novo de trabalho e pesquisa. As autoras relatam uma experiência de trabalho clínico e psicanalítico realizada num Posto de Saúde comunitário, pretendendo - através deste relato - apresentar uma proposta diversa dos modelos anteriormente constituidos


Assuntos
Masculino , Feminino , Humanos , Psicanálise , Serviços de Saúde Comunitária
17.
Int J Cancer ; 82(1): 145-50, 1999 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-10360834

RESUMO

Increases in the expression of manganese-dependent superoxide dismutase (MnSOD) have been detected in several classes of human and experimental tumors and appear to correlate with poorer prognosis in human neuro-epithelial, ovarian and cervical tumors. To delineate the relevance of MnSOD expression to tumor-cell growth and survival, a human MnSOD cDNA was over-expressed in the HeLa cervical-carcinoma cell line. MnSOD over-expression had marginal effects on the growth of HeLa cells in standard medium, but markedly protected the cells from growth suppression and cell death in conditions of serum deprivation. Serum starvation did not affect expression of endogenous MnSOD in wild-type HeLa cells, but was associated with increases in cell death and in the generation of intracellular oxygen radicals. By contrast, in HT29 colon-carcinoma cells, which are relatively resistant to growth-factor withdrawal, serum deprivation was associated with increases in MnSOD expression and activity. Together these observations suggest that MnSOD provides a mechanism for counteracting the intracellular oxidative processes that impair cell growth and viability in the context of growth-factor withdrawal and, in this context, may promote tumor-cell survival in vivo in conditions normally unfavorable to cell growth.


Assuntos
Superóxido Dismutase/fisiologia , Neoplasias do Colo do Útero/patologia , Divisão Celular , Feminino , Células HT29 , Células HeLa , Humanos , Neoplasias do Colo do Útero/enzimologia
18.
Neurosci Lett ; 250(3): 173-6, 1998 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-9708860

RESUMO

Substantial evidence supports the hypothesis that oxygen free radicals are involved in various neurodegenerative disorders. To assess the presence of oxidative stress in Alzheimer's disease (AD) we examined the activity of the enzyme copper-zinc superoxide dismutase (CuZnSOD) in red blood cells, the levels of the mitochondrial inducible enzyme manganese superoxide dismutase (MnSOD) mRNA in lymphocytes, and the total radical-trapping antioxidant capacity (TRAP) in plasma of AD patients and in a group of age-matched non-demented controls. We found that CuZnSOD activity (P < 0.01 vs. controls) was significantly increased as well as the MnSOD mRNA levels while the total antioxidant status (P < 0.001 vs. controls) was decreased in AD patients. These findings support the role of oxidative alterations in the pathogenetic mechanism underlying AD neurodegeneration.


Assuntos
Doença de Alzheimer/enzimologia , Manganês/metabolismo , Estresse Oxidativo/fisiologia , Superóxido Dismutase/biossíntese , Idoso , Doença de Alzheimer/metabolismo , Feminino , Humanos , Masculino , RNA Mensageiro/análise
19.
FEBS Lett ; 403(2): 131-5, 1997 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-9042952

RESUMO

Mitochondrial superoxide dismutase (MnSOD) is usually diminished in cancer cells. We observed that in vivo treatment with LPS produces a strong increase of MnSOD mRNA levels and a weak induction of an inactive protein in rat hepatocarcinomas. In normal liver iron deficiency, obtained with desferrioxamine administration, produces a decrease in the MnSOD induction by LPS, indicating that such induction could depend on tissue iron content. However, no change in MnSOD mRNA has been observed in iron-overloaded tumor tissue. Thus, iron is possibly involved in the transcriptional regulation of the protein, in combination with some other unknown factor that appears to be deficient in tumor cells.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Ferro/farmacologia , Lipopolissacarídeos/farmacologia , Superóxido Dismutase/genética , Animais , Desferroxamina/farmacologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/patologia , Transplante de Neoplasias , Ratos , Ratos Endogâmicos
20.
Br J Cancer ; 74(12): 1877-85, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8980385

RESUMO

The oxy-radical scavenger enzyme manganese superoxide dismutase (MnSOD) may act in the capacity of a tumour-suppressor gene. To address the issue of its role in tumour transformation and progression in vivo, we evaluated the content of this enzyme in 33 brain tumours of neuroepithelial origin with different degrees of differentiation (WHO grade II-IV) by means of Western blot and immunohistology. Our results show that immunoreactive MnSOD increases in a direct relationship with tumour grade and is therefore inversely correlated with differentiation. The increase in induced at a pretranscriptional level and is apparently specific to brain tumours of neuroepithelial origin. Approximately 30% of grade IV tumours display low levels of MnSOD content, and preoperative radiotherapy and brachytherapy result in low amounts of enzyme. Based upon these observations, we suggest that MnSOD cannot be considered a classical tumour-suppressor gene.


Assuntos
Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia , Neoplasias Neuroepiteliomatosas/enzimologia , Neoplasias Neuroepiteliomatosas/patologia , Superóxido Dismutase/metabolismo , Adolescente , Adulto , Idoso , Anticorpos Monoclonais/análise , Western Blotting/métodos , Neoplasias Encefálicas/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Neuroepiteliomatosas/genética , Neuroglia/química , Prognóstico , RNA Mensageiro/química , RNA Neoplásico/análise , Taxa de Sobrevida
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