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1.
Neurochem Res ; 35(12): 1922-32, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20725780

RESUMO

Deprenyl has been discovered by Knoll and co-workers. The R-enantiomer of deprenyl (selegiline) is a selective and irreversible inhibitor of the B-isoform of monoamine oxidase (MAO-B) enzyme. Due to its dopamine potentiating and possible neuroprotective properties it has an established role in the treatment of parkinsonian patients. By inhibiting MAO-B enzyme, R-deprenyl decreases the formation of hydrogen peroxide, alleviating the oxidative stress also reduced by increased expression of antioxidant enzymes (superoxide dismutases and catalase) reported during chronic treatment. It was shown to prevent the detrimental effects of neurotoxins like MPTP and DSP-4. R-Deprenyl elicits neuroprotective and neuronal rescue activities in concentrations too low to inhibit MAO-B. It is extensively metabolized and some of the metabolites possess pharmacological activities, thus their contribution to neuroprotective properties was also suggested. The recently identified deprenyl-N-oxide is extensively studied in our laboratory. Effects other than neuroprotection, like influencing cell adhesion and proliferation cannot be neglected.


Assuntos
Inibidores da Monoaminoxidase/farmacologia , Selegilina/farmacologia , Animais , Humanos , Inibidores da Monoaminoxidase/farmacocinética , Fármacos Neuroprotetores/farmacocinética , Fármacos Neuroprotetores/farmacologia , Selegilina/farmacocinética , Estereoisomerismo
2.
J Neural Transm (Vienna) ; 117(6): 695-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20454984

RESUMO

Postulated cytoprotective action of (-)-deprenyl (D), (-)-desmethyl-deprenyl (DD) and (-)-deprenyl-N-oxide (DNO) on L-buthionine-(S,R)-sulfoximine (BSO) toxicity was investigated using in vitro cultures of serum-deprived A-2058 melanoma cells. BSO (10 microM/l) decreased viable cell number and mitotic rate, while increased the apoptotic index. D and both of its metabolites, given together with BSO in the concentration of 50 microM/l, mitigated cell loss and decreased the apoptotic ratio. DD was the most effective compound in decreasing apoptotic activity, while DNO stabilized the cell number on control level and increasing the ratio of mitotic cells above the only serum-deprived control. Surveillance on mitochondrial membrane stability and antioxidant properties may play an important role in these processes.


Assuntos
Anfetaminas/farmacologia , Citoproteção/efeitos dos fármacos , Glutationa/farmacologia , Inibidores da Monoaminoxidase/farmacologia , Selegilina/análogos & derivados , Butionina Sulfoximina/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Interações Medicamentosas , Citometria de Fluxo/métodos , Humanos , Melanoma/patologia , Radiossensibilizantes , Selegilina/farmacologia , Soro/metabolismo
3.
Clin Exp Rheumatol ; 24(3): 325-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16870104

RESUMO

OBJECTIVE: To investigate the effect of the fermented wheat germ extract (Avemar)in patients with severe rheumatoid arthritis (RA). METHODS: Fifteen female RA (Steinbrocker II-III) patients, who had unsuccessfully tried two different DMARD treatments, were enrolled in an open-label, 1-year long, pilot clinical study. DMARD and steroid therapies were recorded and continued. All patients received Avemar as additional therapy. For measurement of efficacy the Ritchie Index, the Health Assessment Questionnaire (HAQ) and the assessment of morning stiffness were applied. Patients were evaluated at baseline, 6 and 12 months. For statistical analyses the Wilcoxon test was used. RESULTS: At both 6 and 12 months, Ritchie index, HAQ and morning stiffness showed significant improvements compared with the baseline values. Dosages of steroids could be reduced in about half of the patients. No side effects of Avemar were observed. CONCLUSION: Supplementation of standard therapies with a continuous administration of Avemar is beneficial for RA patients.


Assuntos
Artrite Reumatoide/dietoterapia , Extratos Vegetais/administração & dosagem , Triticum , Artrite Reumatoide/fisiopatologia , Suplementos Nutricionais , Feminino , Nível de Saúde , Humanos , Articulações/efeitos dos fármacos , Articulações/fisiopatologia , Projetos Piloto , Índice de Gravidade de Doença , Inquéritos e Questionários
4.
J Natl Cancer Inst ; 82(6): 513-7, 1990 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-2156080

RESUMO

Female BDF1 mice bearing MXT mammary adenocarcinomas were treated for 3 weeks with the luteinizing hormone-releasing hormone (LH-RH) antagonist [Ac-D-Nal(2)1, D-Phe(4Cl)2, D-Pal(3)3, D-Cit6, D-Ala10]-LH-RH (SB-75), with the agonist D-Trp6-LH-RH, with tamoxifen (5 micrograms per animal per day subcutaneously), with the combination of D-Trp6-LH-RH and tamoxifen, or by surgical ovariectomy. SB-75 and D-Trp6-LH-RH were administered in the form of microcapsules releasing 25 micrograms/day. The reduction in tumor weights after treatment with SB-75, D-Trp6-LH-RH, D-Trp6-LH-RH plus tamoxifen, or ovariectomy was 84%, 64%, 33%, and 67%, respectively. Tamoxifen alone was ineffective. Histologically, the regressive changes in the treated tumors were characteristic of apoptosis (programmed cell death). In view of its potency and its immediate inhibitory effect, the LH-RH antagonist SB-75 should be considered as a possible new hormonal agent for the treatment of breast cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Hormônio Liberador de Gonadotropina/análogos & derivados , Neoplasias Mamárias Experimentais/tratamento farmacológico , Animais , Antineoplásicos , Peso Corporal/efeitos dos fármacos , Receptores ErbB/metabolismo , Feminino , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hormônio Liberador de Gonadotropina/uso terapêutico , Fator de Crescimento Insulin-Like I/metabolismo , Hormônio Luteinizante/sangue , Neoplasias Mamárias Experimentais/patologia , Camundongos , Receptores de Superfície Celular/metabolismo , Receptores do LH/metabolismo , Receptores de Somatomedina
5.
Cancer Res ; 50(12): 3716-21, 1990 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-2160323

RESUMO

Groups of 15 female Syrian golden hamsters with N-nitrosobis(2-oxopropyl)amine-induced pancreatic cancers were treated for 2 mo with microcapsules of the luteinizing hormone-releasing hormone (LH-RH) antagonist [Ac-D-Nal(2)1-D-Phe(4Cl)2-D-Pal(3)3,D-Cit6,D-Ala10] LH-RH (SB-75) releasing 8 micrograms/day or with the microcapsules of the LH-RH agonist D-tryptophan-6-luteinizing hormone-releasing hormone (D-Trp-6-LH-RH) releasing 8 micrograms/day or 25 micrograms/day. Chronic treatment with SB-75 resulted in 70% inhibition of pancreatic tumor weight; D-Trp-6-LH-RH in doses of 8 micrograms/day and 25 micrograms/day produced 66% and 62% inhibition, respectively. The number of animals with pancreatic tumors was reduced by about 50% in each treated group. Tumorous ascites were found in seven control hamsters and in one hamster in each group treated with D-Trp-6-LH-RH but not in the group given SB-75. Reduction in serum luteinizing hormone levels and ovarian as well as uterine weights indicated that an inhibition of the pituitary-gonadal axis occurred during chronic SB-75 and D-Trp-6-LH-RH treatment. Membrane receptor assays showed a significant decrease of the concentration of binding sites for LH-RH in tumor cells after SB-75 or D-Trp-6-LH-RH treatment. Insulin-like growth factor I receptors, but not epidermal growth factor receptors, were down-regulated by D-Trp-6-LH-RH. SB-75 did not influence the concentration or the binding capacity of insulin-like growth factor I and epidermal growth factor receptors in the tumor cells. The inhibitory effect of chronic treatment with SB-75 and D-Trp-6-LH-RH on tumor growth was mediated by enhanced apoptosis (programmed cell death) induced by the change in hormonal environment. Apoptosis was also produced in hamsters with N-nitrosobis(2-oxopropyl)amine-induced pancreatic cancers by acute treatment (3 to 6 days) with high doses of D-Trp-6-LH-RH or SB-75. In view of its potency and an immediate powerful inhibitory effect, the LH-RH antagonist SB-75 might be considered as a possible new hormonal agent for the treatment of exocrine pancreatic cancer.


Assuntos
Antineoplásicos/uso terapêutico , Hormônio Liberador de Gonadotropina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Cricetinae , Feminino , Hormônio Liberador de Gonadotropina/uso terapêutico , Mesocricetus , Nitrosaminas , Neoplasias Pancreáticas/análise , Neoplasias Pancreáticas/induzido quimicamente , Neoplasias Pancreáticas/patologia , Receptores de Superfície Celular/análise , Receptores do LH/análise , Receptores de Somatomedina , Indução de Remissão , Pamoato de Triptorrelina
6.
Cell Signal ; 10(4): 277-82, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9617485

RESUMO

Flow cytometric and electron microscopic immunocytochemical studies have been performed in HT-29 human colon tumour cells in vitro, to determine and localise p86 Ku protein, which is a regulatory subunit of DNA-dependent kinase and a specific binding site for somatostatin. We have demonstrated that HT-29 cells contain p86 Ku and that the distribution between the cytoplasm and the nucleus is even. After administration of the somatostatin analogues Sandostatin and TT-232 to HT-29 cells, the p86 Ku content of the cytoplasmic compartment decreased in the first 4 h. An increase in the content of this protein in the nuclear compartment was observed at hour 1 followed by a decrease at hour 4 after treatment. Quantitative differences between the two analogues have been observed in this respect. The practical significance of these findings is discussed.


Assuntos
Antígenos Nucleares , Antineoplásicos/farmacologia , Autoantígenos/metabolismo , Núcleo Celular/metabolismo , Citosol/metabolismo , DNA Helicases , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/metabolismo , Octreotida/farmacologia , Peptídeos Cíclicos/farmacologia , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/imunologia , Núcleo Celular/imunologia , Citosol/imunologia , Células HT29 , Humanos , Autoantígeno Ku , Somatostatina/análogos & derivados
7.
Eur J Ophthalmol ; 15(1): 17-22, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15751234

RESUMO

PURPOSE: To elucidate the pathomechanism of Fuchs' dystrophy and pseudophakic bullous keratopathy (PBK) by examining cell apoptosis in different corneal layers. METHODS: The authors studied corneal buttons obtained from 21 eyes following central penetrating keratoplasty: 14 corneal buttons (13 patients, age 70.8+/-10.0 years) with Fuchs' dystrophy, and 7 buttons (7 patients, age 69.6+/-10.2 years) with PBK. Four buttons from enucleated eyes with choroidal melanoma served as controls. Histologic changes were examined using light microscopy with hematoxylin-eosin (HE) staining. The average numbers of apoptotic cells per field of view (125x magnification) in separate samples of the epithelial, stromal, and endothelial layers were determined using the TUNEL (terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick-end labeling) assay. RESULTS: In 11 of the Fuchs' dystrophy corneas and 2 of the PBK corneas, apoptotic activity was detected. In the control corneas no apoptotic activity was found. Compared to the controls there was a statistically significant difference in the mean (normalized) apoptotic cell numbers for all three layers (p=0.01 in each case) in the Fuchs' dystrophy corneas, and for the stromal layer (p<0.01) in PBK corneas. The apoptotic cell numbers for the epithelial and endothelial layers of the latter were higher, but the difference was not statistically significant (p=0.07, 0.07). CONCLUSIONS: Apoptosis may play a role in the pathomechanism of Fuchs' dystrophy and in keratocyte death in corneas with PBK.


Assuntos
Apoptose , Doenças da Córnea/patologia , Substância Própria/patologia , Endotélio Corneano/patologia , Epitélio Corneano/patologia , Distrofia Endotelial de Fuchs/patologia , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Células Epiteliais/patologia , Feminino , Fibroblastos/patologia , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Pessoa de Meia-Idade
8.
J Clin Endocrinol Metab ; 77(3): 677-82, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8370688

RESUMO

"Nonfunctioning" adrenal adenomas are often diagnosed in patients without recognizable clinical symptoms of adrenocortical hyperfunction. The objective of this study was to determine directly the steroidogenic activity of such adenomas (n = 12) and compare them histologically and functionally to normal human adrenals (n = 6) and aldosterone-producing adenomas (n = 15). The histological appearances of nonfunctioning and aldosterone-producing adenomas were surprisingly similar. Nonfunctioning adrenal adenomas expressed all mRNAs of P450scc, P450c17, P450c21, adrenodoxin, and adrenodoxin reductase with relative levels comparable to those found in normal adrenals. Consistent with their hormone-producing nature, these adenomas had cortisol and aldosterone contents as high as those in normal adrenal tissues, a significantly (P < 0.05) increased 17-hydroxyprogesterone content, and a disproportionally low expression of P450c21 mRNA compared to aldosterone-producing adenomas. Cells isolated from both aldosterone-producing and nonfunctioning adrenal adenomas exhibited highly ACTH-sensitive cortisol and aldosterone production, suggesting again the presence of both zona glomerulosa-like and zona fasciculata-like steroidogenesis in these adenoma tissues. These results indicate that so-called nonfunctioning adrenal adenomas are not without steroidogenic activity. Therefore, the assumption that adrenal adenomas are entirely nonfunctioning in the absence of recognizable hormonal hyperfunction may not be correct.


Assuntos
Adenoma/enzimologia , Corticosteroides/biossíntese , Neoplasias do Córtex Suprarrenal/enzimologia , Aldosterona/biossíntese , RNA Mensageiro/metabolismo , Adrenodoxina/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Ferredoxina-NADP Redutase/genética , Humanos , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 21-Hidroxilase/genética
9.
Cell Prolif ; 34(3): 135-41, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11380483

RESUMO

Formaldehyde was applied in various doses (0.1-10.0 mM) to HT-29 human colon carcinoma and HUV-EC-C human endothelial cell cultures. Cell number, apoptotic and mitotic index as well as proportion of cells in S-phase was investigated by morphological methods and flow cytometry. Ten mM of formaldehyde caused high degree of cell damage and practically eradicated the cell cultures. One mM of formaldehyde enhanced apoptosis and reduced mitosis in both types of cell cultures, in a moderate manner. The low dose (0.1 mM) enhanced cell proliferation and decreased apoptotic activity of the cultured cells, the tumour cells appeared to be more sensitive. The possible role of this dose-dependent effect of formaldehyde in various pathological conditions, such as carcinogenesis and atherogenesis is discussed with emphasis on the eventual interaction between formaldehyde and hydrogen peroxide.


Assuntos
Desinfetantes/farmacologia , Endotélio Vascular/citologia , Formaldeído/farmacologia , Apoptose/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Desinfetantes/química , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Citometria de Fluxo , Formaldeído/química , Células HT29 , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Fase S/efeitos dos fármacos , Veias Umbilicais/citologia
10.
Curr Med Chem ; 11(15): 2017-31, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15279565

RESUMO

Deprenyl, the selective irreversible inhibitor of monoamine oxidase-B (MAO-B), has been synthesised as a potential antidepressant, however, due to its dopamine potentiating capacity, became a registered drug in the treatment of Parkinson's disease. Deprenyl possesses a wide range of pharmacological activities; some of them are not related to its MAO-B inhibitory potency. Beside its dopamine potentiating effect, it renders protection against a number of dopaminergic, cholinergic and noradrenergic neurotoxins with a complex mechanism of action. By inducing antioxidant enzymes and decreasing the formation of reactive oxygen species, deprenyl is able to combat an oxidative challenge implicated as a common causative factor in neurodegenerative diseases. In a dose substantially lower than required for MAO-B inhibition (10(-9)-10(-13) M), deprenyl interferes with early apoptotic signalling events induced by various kinds of insults in cell cultures of neuroectodermal origin, thus protecting cells from apoptotic death. Deprenyl requires metabolic conversion to a hitherto unidentified metabolite to exert its antiapoptotic effect, which serves to protect the integrity of the mitochondrion by inducing transcriptional and translational changes. Pharmacokinetic and metabolism studies have revealed that deprenyl undergoes intensive first pass metabolism, and its major metabolites also possess pharmacological activities. The ratio of the parent compound and its metabolites reaching the systemic circulation and the brain are highly dependent on the routes of administration. Therefore, in the treatment of neurodegenerative diseases, reconsideration of the dosing schedule, by lowering the dose of deprenyl and choosing the most appropriate route of administration, would diminish undesired adverse effects, with unaltered neuroprotective potency.


Assuntos
Inibidores da Monoaminoxidase/farmacologia , Selegilina/farmacologia , Animais , Humanos
11.
Eur J Cancer ; 32A(7): 1102-8, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8758238

RESUMO

Admission, clinical and autopsy diagnoses of tumour were computed in 2000 consecutive cases, aged 30-80 years, using data collected in two university pathology departments in Budapest, Hungary. Based on diagnosis of tumour, regardless of site, as the underlying cause of death false-negative rates were 37.4% at admission and 8.8% clinically. Corresponding false-positive rates were 8.4 and 9.1%. General practitioners who correctly diagnosed a tumour as the cause of the terminal illness identified the primary site wrongly in 20.6% (90/436) of cases. Hospital clinicians did so in 20.4% (130/636) of cases. Overall, of site-specific tumours considered as the underlying cause of death at autopsy, 27.4% were incorrectly diagnosed clinically and 50.4% at admission. Diagnostic errors were particularly common for tumours of the lung, liver, ovary and gall bladder. Graduate and postgraduate education, planning of the health care system and quality of cancer care may benefit from statistical data derived from autopsy diagnoses.


Assuntos
Autopsia , Neoplasias/diagnóstico , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Erros de Diagnóstico , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Distribuição por Sexo
12.
J Med Chem ; 42(19): 4010-3, 1999 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-10508449

RESUMO

Lipoamino acid and liposaccharide conjugates of somatostatin analogue TT-232 were synthesized to modify the physicochemical properties of the parent peptide. The relative position, the number, and the nature of the lipid and/or saccharide moieties were varied. Experiments in vitro clearly showed that many compounds modified at the N- and/or C-terminus with lipid or sugar moieties retained the biological activity of the parent compound. An interesting construct was synthesized containing lipid and sugar units at opposite ends of the somatostatin analogue, so that the entire molecule could be considered as an amphipathic surfactant.


Assuntos
Glicopeptídeos , Lipopolissacarídeos , Oligopeptídeos , Somatostatina/análogos & derivados , Somatostatina/administração & dosagem , Administração Oral , Antineoplásicos/administração & dosagem , Células CACO-2 , Sequência de Carboidratos , Divisão Celular/efeitos dos fármacos , Humanos , Absorção Intestinal/efeitos dos fármacos , Dados de Sequência Molecular , Peptídeos Cíclicos/administração & dosagem , Relação Estrutura-Atividade
13.
Cancer Lett ; 167(2): 157-62, 2001 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-11369136

RESUMO

The application of most agents with the capacity to reverse multidrug resistance (MDR) via modulation of the multidrug transporter P-glycoprotein (Pgp) was shown to be associated with toxic side-effects. For this reason, we have investigated the effect of combinations of suboptimal concentrations of Pgp blockers on the induction of apoptosis and growth arrest in daunorubicin (D) treated, MDR1 gene transfected cells. We used verapamil, PSC833 and Cremophor EL as Pgp modulators, which affect the function of Pgp by different mechanisms. Treatment of NIH3T3/MDR1 cells with combinations of suboptimal concentrations of Pgp modulators in the presence of D caused apoptosis and G(2) arrest to the same extent as optimal concentrations of singly used blockers. We conclude that combinations of suboptimal concentrations of Pgp modulators may cause effective sensitization of resistant tumor cells, and at the same time, may avoid the frequently observed toxic effects experienced in clinical trials with a single modifier applied at the optimal dose.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antibióticos Antineoplásicos/farmacologia , Apoptose , Ciclosporinas/farmacologia , Daunorrubicina/farmacologia , Células 3T3 , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Animais , Divisão Celular/efeitos dos fármacos , Combinação de Medicamentos , Interações Medicamentosas , Fase G2/efeitos dos fármacos , Glicerol/análogos & derivados , Glicerol/farmacologia , Camundongos , Verapamil/farmacologia
14.
Hum Pathol ; 28(7): 866-9, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9224758

RESUMO

A case of multifocal hemangioendothelioma of the liver, adrenal gland, and placenta is reported. The histological appearance of the tumor is consistent with an infantile hemangioendothelioma, type 2. Multifocal development is the most obvious explanation for the disease but the possibility that this represents malignant placental neoplasm with metastases requires consideration.


Assuntos
Neoplasias das Glândulas Suprarrenais/patologia , Doenças Fetais/patologia , Hemangioendotelioma/patologia , Neoplasias Hepáticas/patologia , Doenças Placentárias/patologia , Complicações Neoplásicas na Gravidez , Feminino , Humanos , Gravidez
15.
J Thorac Cardiovasc Surg ; 89(3): 462-5, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3974283

RESUMO

We have observed 741 mediastinal tumors during the past 25 years. Among these tumors, two intrathoracic vagal tumors were found; one bilateral neurofibrosarcoma and one neurilemmoma. To date, 49 intrathoracic vagal tumors have been reported in the literature, and the neurofibrosarcoma described here is the fourth malignant vagal tumor reported.


Assuntos
Neoplasias dos Nervos Cranianos , Neurilemoma , Neurofibroma , Neoplasias Torácicas , Nervo Vago , Adulto , Neoplasias dos Nervos Cranianos/diagnóstico por imagem , Neoplasias dos Nervos Cranianos/patologia , Feminino , Humanos , Masculino , Neurilemoma/diagnóstico por imagem , Neurilemoma/patologia , Neurofibroma/diagnóstico por imagem , Neurofibroma/patologia , Radiografia , Neoplasias Torácicas/diagnóstico por imagem , Neoplasias Torácicas/patologia , Nervo Vago/diagnóstico por imagem , Nervo Vago/patologia
16.
Exp Mol Med ; 32(2): 88-92, 2000 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-10926121

RESUMO

Experimental data suggest that Resveratrol, a compound found in grapes and other fruits may influence cell proliferation and apoptosis. The aim of our experiments was to study the effect of Resveratrol on tumor cell cultures and an endothelial cell culture in order to examine the effect of various doses of this compound on active cell death and cell proliferation. Human tumor (HT-29, SW-620, HT-1080) and endothelial (HUV-EC-C) cells were treated with various doses of (0.1 to 100.0 microg/ml) Resveratrol in vitro. Cell number, apoptotic and mitotic index was measured 24, 48 and 72 h after treatment. Low doses (0.1-1.0 microg/ml) of Resveratrol enhance cell proliferation, higher doses (10.0-100.0 microg/ml) induce apoptosis and decrease mitotic activity, which is reflected in changes of cell number. Resveratrol influences dose dependently the proliferative and apoptotic activity of human tumor and endothelial cells. The possible role of formaldehyde in the mechanism of action of Resveratrol is discussed.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose , Endotélio/efeitos dos fármacos , Mitose/efeitos dos fármacos , Estilbenos/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Endotélio/citologia , Humanos , Resveratrol , Células Tumorais Cultivadas
17.
Cancer Cell Int ; 2(1): 4, 2002 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-12076354

RESUMO

Isopeptides (ϵ-peptides) of lysine, with a given Mw and low polydispersity (10-400 units), were synthesized to study the relationship between their chemical structure and biological effect. The designed compounds were of high purity, low polydispersity and high stereochemical purity. The effect of the compounds was tested on a human erythroleukemia cell line (K-562) and on four transplantable mouse tumors (L1210 lymphoid leukemia, P38 macrophage derived tumor, Ehrlich ascites carcinoma, Lewis lung tumor /LLT/). In case of the L1210 and P388 tumors and the Ehrlich carcinoma, survival of the animals was used as an indicator of the effect. In case of the Lewis lung tumor, the number and size of metastases in the lung and/or liver of treated and untreated mice were used as indicators. The polymers of polymerisation degree 80-120 (Mw 10.2-15.4 KD) showed the strongest antiproliferative effect both on K562 cells and the tumors growing in vivo. This effect was manifest with a significantly higher survival rate as compared to the control (L1210, P38, Ehrlich ascites), furthermore, by a decrease in the number and size of liver and lung metastases (LLT).

18.
J Steroid Biochem Mol Biol ; 66(1-2): 27-33, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9712408

RESUMO

The presence of p53 and tissue transglutaminase (tTG) gene expressions was investigated in human normal and pathologic adrenal tissues with two aims (1) to determine the tissue content of p53 protein, its messenger ribonucleic acid (mRNA) and, especially, tTG mRNA which has not been previously reported and (2) to study possible differences in the coexpression of p53 and tTG in various adrenal disorders. Using Northern blot analysis, p53 and tTG mRNAs were detected in each adrenal tissue examined including 5 normal human adrenals, 6 aldosterone-producing adenomas, 3 Cushing's adenomas, 1 primary nodular adrenocortical hyperplasia causing Cushing's syndrome in an infant, 12 non-hyperfunctioning adrenocortical adenomas, and 4 adrenocortical carcinomas. The results showed a significant positive correlation between these two mRNAs in all adrenal tissues except adrenocortical carcinomas. Compared to normal adrenals, high p53 mRNA levels were observed in aldosterone-producing and Cushing's adenomas and, most markedly, in a tissue from a primary nodular adrenocortical hyperplasia. Also, Cushing's adenomas had significantly higher tTG mRNA contents. Immunohistochemistry for wild-type and mutant p53 protein showed numerous p53 positive cells with a strong nuclear staining in a tissue from a primary nodular adrenocortical hyperplasia, whereas the p53 positive cells were absent, except those with a faint nuclear staining, in all other adrenal tissues. However, all adrenal tissues showed detectable p53 contents by the more sensitive method of luminometric immunoassay (LIA). Using this method, aldosterone-producing adenomas exhibited significantly higher p53 contents than normal adrenal tissues. These observations may support potentially important roles for p53 and tTG in adrenal pathophysiology, especially in mechanisms which influence the evolution and/or progression of aldosterone-producing and Cushing's adenomas and, most probably, hyperplasias.


Assuntos
Glândulas Suprarrenais/patologia , Regulação da Expressão Gênica/genética , Genes p53/genética , Transglutaminases/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Aldosterona/metabolismo , Humanos , Imuno-Histoquímica , Proteínas de Neoplasias/genética , RNA Mensageiro/metabolismo , Proteína Supressora de Tumor p53/análise
19.
J Steroid Biochem Mol Biol ; 37(6): 1061-7, 1990 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-1981009

RESUMO

Many clinical approaches for the treatment of hormone-sensitive tumors are being developed based on analogs of LH-RH and somatostatin. Inhibition of the pituitary-gonadal axis forms the basis for oncological applications of LH-RH agonists like [D-Trp6]-LH-RH and new LH-RH antagonists free of edematogenic effects such as [Ac-D-Nal(2)1-D-Phe(4Cl)2-D-Pal(3)3,D-Cit6,D-Ala10]-LH -RH (SB-75). Agonists and antagonists of LH-RH have been used in patients with prostate cancer and might be also beneficial for the treatment of breast cancer and ovarian, endometrial and pancreatic carcinomas. Some of the effects of LH-RH analogs can be due to direct action since LH-RH receptors have been found in these cancers. The use of sustained delivery systems based on microcapsules of PLG, makes the treatment more efficacious. Octapeptide analogs of somatostatin such as D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH2 (RC-160) and related analogs were designed specifically for antitumor activity. These somatostatin analogs, by virtue of having a wide spectrum of activities appear to inhibit various tumors through multiple mechanisms. Direct antiproliferative actions of somatostatin analogs appear to be mediated by specific receptors located on tumor cells. High affinity binding sites for RC-160 and related analogs have been found in human pancreatic, prostate, breast and ovarian cancers and brain tumors such as meningiomas. In vivo administration of analog RC-160 inhibits the growth of Dunning R-3327 prostate cancers in rats, MXT mammary tumors in mice and BOP-induced ductal pancreatic cancers in hamsters. Combination of microcapsules of RC-160 with [D-Trp6]-LH-RH results in synergistic potentiation of the inhibition of these cancers. Somatostatin analog RC-160 and LH-RH antagonist SB-75 are the object of further experimental studies and clinical trials aimed at the exploration of their inhibitory effects on the processes of malignant growth.


Assuntos
Antineoplásicos/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Neoplasias/tratamento farmacológico , Sequência de Aminoácidos , Hormônio Liberador de Gonadotropina/análogos & derivados , Humanos , Dados de Sequência Molecular , Somatostatina/análogos & derivados , Somatostatina/farmacologia
20.
J Clin Pathol ; 56(6): 433-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12783970

RESUMO

AIMS: To evaluate a recently developed digital slide and virtual microscope system, and to compare this method with optical microscopy on routine gastrointestinal biopsy specimens in both local and remote access modes. METHODS: A fully computer controlled commercial microscope was used. The scanning program included object detection, autofocus, and image compression algorithms. The overall hard disk space for a gastric biopsy was between 30 and 50 MB and the scanning time was between 20 and 40 minutes. Haematoxylin and eosin stained routine gastric (61) and colon (42) biopsy specimens were selected, scanned, and evaluated by two specialists on an optical (OM) and virtual microscope (VM). RESULTS: The overall concordance of VM and OM with the consensus diagnosis was 95.1% and 97%, respectively. Clinically important concordance was 96.1% and 98% for VM and OM, respectively. The two methods showed concordance in 92% of cases and clinically important concordance in 94.1% of cases. The reasons for discordance were image quality (one case), interpretation difference (three cases), and insufficient clinical information (three cases). Remote evaluation of the digital slides through the Internet has the advantages of the previously used static and dynamic telepathology methods. CONCLUSIONS: Diagnostic concordance was found between OM and VM. The digital slide and the virtual microscope can be alternative techniques in the computerisation of the histology laboratory and in teleconsultation services after further evaluation of time and storage constraints.


Assuntos
Gastroenteropatias/patologia , Processamento de Imagem Assistida por Computador/métodos , Telepatologia/métodos , Algoritmos , Biópsia , Colite/patologia , Neoplasias do Colo/patologia , Gastrite/patologia , Humanos , Internet , Microscopia/métodos , Reprodutibilidade dos Testes , Neoplasias Gástricas/patologia
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