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1.
Oncogene ; 34(20): 2597-608, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25023698

RESUMO

REV-ERBα and REV-ERBß nuclear receptors regulate several physiological processes, including circadian rhythm and metabolism. A previous study reported the REV-ERBα gene to be co-overexpressed with ERBB2 in breast cancer cell lines. Surprisingly, we found that several tumor types, including a number of breast cancer cell lines, predominantly express the REV-ERBß variant. This pattern was independent of ERBB2 and ER status, and opposite to that of non-cancer mammary epithelial HMEC cells, in which REV-ERBα was the major variant. Consistent with this molecular profile, REV-ERB target genes in both circadian and metabolic pathways were derepressed upon silencing of REV-ERBß, but not REV-ERBα. Strikingly, we found that REV-ERBß is a determinant of sensitivity to chloroquine, a clinically relevant lysosomotropic agent that suppresses autophagy. The cytoprotective function of REV-ERBß appears to operate downstream of autophagy blockade. Through compound screening, we identified ARN5187, a novel lysosomotropic REV-ERBß ligand with a dual inhibitory activity toward REV-ERB-mediated transcriptional regulation and autophagy. Remarkably, although ARN5187 and chloroquine share similar lysosomotropic potency and have a similar effect on autophagy inhibition, ARN5187 is significantly more cytotoxic. Collectively, our results reveal that dual inhibition of REV-ERBß and autophagy is an effective strategy for eliciting cytotoxicity in cancer cells. Furthermore, our discovery of a novel inhibitor compound of both REV-ERB and autophagy may provide a scaffold for the discovery of new multifunctional anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Citotoxinas/farmacologia , Neoplasias/tratamento farmacológico , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Proteínas Repressoras/antagonistas & inibidores , Autofagia/genética , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Células Hep G2 , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
2.
Br J Pharmacol ; 167(8): 1620-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22774772

RESUMO

BACKGROUND AND PURPOSE: URB937 is a peripherally restricted inhibitor of the anandamide-deactivating enzyme fatty-acid amide hydrolase (FAAH). Despite its limited access to the CNS, URB937 produces marked antinociceptive effects in rodents. URB937 is actively extruded from the CNS by the ATP-binding cassette (ABC) membrane transporter, Abcg2. Tissue Abcg2 levels are markedly different between males and females, and this transporter is known to limit the access of xenobiotics to the fetoplacental unit in gestating female rodents. In the present study, we investigated the tissue distribution and antinociceptive properties of URB937 in female mice and rats. EXPERIMENTAL APPROACH: We studied the systemic disposition of URB937 in female mice and the antinociceptive effects of this compound in models of visceral (acetic acid-induced writhing) and inflammatory nociception (carrageenan-induced hyperalgesia) in female mice and rats. Furthermore, we evaluated the interaction of URB937 with the blood-placenta barrier in gestating mice and rats. KEY RESULTS: Abcg2 restricted the access of URB937 to the CNS of female mice and rats. Nevertheless, URB937 produced a high degree of antinociception in female mice and rats in models of visceral and inflammatory pain. Moreover, the compound displayed a restricted access to placental and fetal tissues in pregnant mice and rats. CONCLUSIONS AND IMPLICATIONS: Peripheral FAAH blockade with URB937 reduces nociception in female mice and rats, as previously shown for males of the same species. In female mice and rats, Abcg2 limits the access of URB937, not only to the CNS, but also to the fetoplacental unit. LINKED ARTICLES This article is part of a themed section on Cannabinoids. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.167.issue-8.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Amidoidrolases/antagonistas & inibidores , Analgésicos/farmacologia , Canabinoides/farmacologia , Placenta/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Ácido Acético , Amidoidrolases/metabolismo , Analgésicos/uso terapêutico , Animais , Ácidos Araquidônicos/metabolismo , Canabinoides/uso terapêutico , Carragenina , Endocanabinoides/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Regulação da Expressão Gênica , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dor/induzido quimicamente , Dor/tratamento farmacológico , Dor/fisiopatologia , Alcamidas Poli-Insaturadas/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley , Caracteres Sexuais , Distribuição Tecidual
3.
Clin Microbiol Infect ; 17(6): 915-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20718799

RESUMO

To investigate an increased incidence of human cultures growing Salmonella enterica ssp. diarizonae serotype 61:k:1,5,7 in France in 2008, we reviewed medical records of case patients and identified the material used during invasive procedures and for bacterial culture. Trace-back investigations incriminated culture media containing contaminated sheep blood agar.


Assuntos
Meios de Cultura , Erros de Diagnóstico , Surtos de Doenças , Infecções por Salmonella/epidemiologia , Salmonella enterica/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , França/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Infecções por Salmonella/microbiologia , Salmonella enterica/classificação
4.
Transplant Proc ; 42(4): 1188-90, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20534257

RESUMO

Most transplant centers consider severe pulmonary hypertension (PHT) to be an absolute contraindication for orthotopic liver transplantation (OLT). We retrospectively examined the outcome of 24 patients with PHT (group 1) who underwent OLT compared with 24 matched patients (group 2) without PHT, who also underwent OLT. Based on right cardiac catheterization measurements made after the induction of anesthesia for OLT, PHT was defined as mild or moderate-to-severe if the mean pulmonary arterial pressure exceeded 25 or 35 mm Hg, respectively. The incidence of PHT was 9.8% (24/244); 21/24 PHT patients showed mild and 3/24 moderate PHT. Kaplan-Meier survival analysis did not show a significant difference between the two groups. The incidence of pulmonary infections was significantly greater in group 1 (P < .05). The duration of ventilation and intensive care unit stay was similar in the two groups. Echocardiography detected only the three moderate cases of PHT and not the twenty-one cases of mild PHT. Our analysis suggested that mild PHT was common and did not affect patient outcomes after OLT; moderate or severe PHT was uncommon. The two patients with moderate PHT survived OLT and did not succum to PHT during long-term follow-up.


Assuntos
Hipertensão Pulmonar/epidemiologia , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Adulto , Pressão Sanguínea , Carcinoma Hepatocelular/cirurgia , Diástole , Feminino , Hepatite B/complicações , Hepatite C/complicações , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/mortalidade , Hepatopatias/classificação , Hepatopatias/cirurgia , Falência Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sístole , Ultrassonografia
5.
J Clin Microbiol ; 47(9): 2906-11, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19625478

RESUMO

Human immunodeficiency viruses (HIV) have a high level of genetic diversity. The outlier variants of HIV type 1 (HIV-1) group O are distantly related to HIV-1 group M. Their divergence has an impact on serological diagnosis, with a risk of false-negative results. In this study, we report 20 failure cases, involving patients with primary or chronic infection, in France and Cameroon between 2001 and 2008. Our results indicate that some assays detected group O infection much less efficiently than others. Two major reasons for these false-negative results were identified: the presence or absence of a group O-specific antigen (and the designed sequence) for the detection of antibodies and the greater envelope variability of group O than of group M strains. This study highlights the complexity of screening for these divergent variants and the need to evaluate test performance with a large panel of strains, due to the extensive diversity of group O variants.


Assuntos
Reações Falso-Negativas , Anticorpos Anti-HIV/sangue , Antígenos HIV/sangue , Infecções por HIV/diagnóstico , HIV-1/classificação , HIV-1/imunologia , Testes Sorológicos/métodos , Camarões , Feminino , França , Variação Genética , Humanos , Masculino
6.
Br J Pharmacol ; 158(1): 382-91, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19552692

RESUMO

BACKGROUND AND PURPOSE: Cannabinoid-2 (CB(2)) receptor-selective agonists have shown anti-nociceptive activity in models of neuropathic and inflammatory pain, and the two agonists most widely used, (+/-)AM1241 [(2-iodo-5-nitrophenyl)-[1-(1-methylpiperidin-2-ylmethyl)-1H-indol-3-yl-methanone] and L768242 [(2,3-dichloro-phenyl)-[5-methoxy-2-methyl-3-(2-morpholin-4-yl-ethyl)-indol-1-yl]-methanone] (GW405833), have been suggested to be protean agonists. Here we investigated the role of the constitutive activity of CB(2) receptors in (+)AM1241 and L768242 protean agonism. EXPERIMENTAL APPROACH: Pharmacological profiles of CB(2) receptor ligands were evaluated in Chinese hamster ovary cells expressing recombinant human (hCB(2)) or rat (rCB(2)) receptors, by measuring modulation of cAMP. To assess the influence of constitutive activity on pharmacological profile, constitutive activity was abolished by pretreatment with AM630 [(6-iodo-2-methyl-1-[2-(4-morpholinyl)ethyl]-1H-indol-3-yl](4-methoxyphenyl) methanone)], followed by extensive washing. KEY RESULTS: In cell lines expressing either hCB(2) or rCB(2) receptors, (+)AM1241 did not reverse forskolin stimulation of cAMP levels. Conversely, L768242 was an inverse agonist at both hCB(2) and rCB(2) receptors. Abolition of constitutive activity disclosed (+)AM1241 and L768242 agonist activity, while activity of CP55940 [5-(1,1-dimethylheptyl)-2-[(1R,2R,5R)-5-hydroxy-2-(3-hydroxy-propyl)-cyclohexyl]-phenol] was unaffected and AM630 became a neutral antagonist. In presence of constitutively active CB(2) receptors, (+)AM1241 antagonized CP55940, but when constitutive activity was abolished, it acted as a partial agonist with additive or antagonistic behaviour, depending on concentration. CONCLUSIONS AND IMPLICATIONS: These results show that (+)AM1241 and L768242 are protean agonists at both hCB(2) and rCB(2) receptors. Abolition of constitutive activity reveals the agonist activity of these compounds. Thus, differences between in vivo and in vitro profiles of CB(2) receptor agonists could be due to different levels of constitutive activity in recombinant versus native CB(2) receptors.


Assuntos
Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/fisiologia , Animais , Células CHO , Canabinoides/farmacologia , Cricetinae , Cricetulus , Cicloexanóis/farmacologia , Relação Dose-Resposta a Droga , Humanos , Indóis/agonistas , Indóis/farmacologia , Ratos
7.
Dig Liver Dis ; 41(8): 586-90, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19131283

RESUMO

BACKGROUND AND AIMS: Serum gamma-glutamyltranspeptidase level is often increased in patients with chronic hepatitis C, and we aimed to identify factors associated with this phenomenon in patients completely abstinent from alcohol (teetotaller). PATIENTS AND METHODS: 71 teetotaller patients have been identified by personal history, questioning of relatives, CAGE questionnaire administration and unscheduled alcoholemia measurements. RESULTS: 39 patients (55%) had elevated (>50IU/L) gamma-glutamyltranspeptidase level. Body mass index, insulin and C-peptide level, insulin resistance, piecemeal necrosis score > or =3, fibrosis score > or =2 and steatosis score > or =1 were significantly higher in these patients than in those (n=32) with normal gamma-glutamyltranspeptidase. At multiple linear regression analysis gamma-glutamyltranspeptidase level was associated with C-peptide level, insulin resistance and histopathologic grading. At multiple logistic regression analysis, C-peptide level (OR=2.13) and piecemeal necrosis score > or =3 (OR=4.59) were the only factors independently associated with elevated gamma-glutamyltranspeptidase. Sustained virological response during pegylated interferon plus ribavirine treatment was achieved by 97% and 49% patients with normal and elevated gamma-glutamyltranspeptidase, respectively (p=0.0001). CONCLUSION: Serum gamma-glutamyltranspeptidase level is often elevated in chronic hepatitis C and is associated with metabolic and inflammatory factors; this phenomenon may contribute to explain and to predict resistance to treatment in this subgroup of patients.


Assuntos
Hepatite C Crônica/metabolismo , Resistência à Insulina , gama-Glutamiltransferase/sangue , Adulto , Peptídeo C/sangue , Enoxacino , Feminino , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/patologia , Humanos , Insulina/sangue , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Temperança
8.
Transplant Proc ; 40(6): 2077-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18675136

RESUMO

Hemophilia B is a congenital recessive disorder caused by deficiency of coagulation factor IX (FIX). Surgical procedures can be performed in patients with hemophilia using high-purity and/or recombinant FIX, which has been shown to be safe and effective in surgical hemostasis. Liver transplantation is the only potentially curative treatment available for these patients, providing a long-term phenotypic cure for hemophilia. End-stage liver disease together with hemophilia exposes patients to greater risks of bleeding complications during the perioperative period with consequent difficulties in managing coagulopathy. The limited experiences reported by different investigators and the various strategies for clotting factor replacement make it difficult to define a single approach with respect to the optimal dose and method of administering FIX to achieve perioperative hemostasis. The limits of plasma-based coagulation tests--prothrombin time, activated partial thromboplastin time--have made thromboelastography a valid alternative in this kind of surgery. It has been demonstrated to be a useful tool for real-time analysis of clot formation using a whole-blood assay format. Further, it accurately illustrates the clinical effects of procoagulant or anticoagulant interventions. In this article, we have described the usefulness of thromboelastography to monitor the ability of high-purity FIX supplementation to restore a normal coagulation state and to guide the perioperative administration of blood products in a successful orthotopic liver transplantation in a hemophilic patient with deficiencies of factors IX and X, presenting with hepatitis C virus-related cirrhosis and hepatocellular carcinoma.


Assuntos
Fator IX/uso terapêutico , Hemofilia B/cirurgia , Transplante de Fígado/métodos , Tromboelastografia , Hemofilia B/complicações , Hepatite C/complicações , Hepatite C/cirurgia , Humanos , Falência Hepática/cirurgia , Falência Hepática/virologia , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico
9.
Arch Gerontol Geriatr ; 44 Suppl 1: 133-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17317446

RESUMO

Antipsychotic drugs are widely used in people with dementia to treat neuropsychiatic symptoms such as aggression, agitation and psychosis. Using antipsychotic agents in older patients is difficult, because it depends on co-morbid conditions, side effects, dosing strategies, duration of treatments and combinations of various medications. This paper discusses the use of atypical antipsychotics in a 1-year-observation on a group of patients followed by an expert dementia center.


Assuntos
Antipsicóticos/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Antipsicóticos/efeitos adversos , Doenças dos Gânglios da Base/induzido quimicamente , Transtornos Cerebrovasculares/induzido quimicamente , Transtornos Cognitivos/induzido quimicamente , Feminino , Humanos , Masculino , Polimedicação
10.
Eur J Neurosci ; 23(6): 1530-8, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16553616

RESUMO

In mouse the cannabinoid receptor 2 (CB2) agonists L768242 and (+)-AM1241, at doses of 30 mg/kg i.p. and 1 and 3 mg/kg i.v., respectively, reduced the second phase of nocifensive behaviors elicited by formalin intraplantar injection. This effect was counteracted by the selective CB2 antagonist SR144528 (1 mg/kg i.p.). In rat (+)-AM1241 (3 and 6 mg/kg i.v.) and L768242 (30 mg/kg i.p.) reduced allodynia elicited by L5-L6 spinal nerve ligation. SR144528 reverted these effects, supporting a CB2-mediated action. To clarify the mechanisms underlying these effects we investigated CB2 gene expression and function in the nervous system. CB2 mRNA was expressed in spinal cord and dorsal root ganglia (DRG) of both sham and neuropathic rats and was up-regulated in the ipsilateral spinal cord of neuropathic rats. Expression studies demonstrated the presence of CB2 mRNA in culture of spinal cord microglia. A biomarker, CGRP, was used to investigate modulation of DRG primary afferents by CB2 agonists. Both L768242 and (+)-AM1241 dose dependently (EC50 of 3.6 and 4.5 nM, respectively) reduced capsaicin-induced calcitonin gene-related peptide (CGRP) release. Coadministration of SR144528 resulted in a rightforward shift (pKB 8.1 and 8.2 for (+)-AM1241 and L768242, respectively) of the dose-response curve. Experiments on capsaicin-induced CGRP release in tissue from CB1-/- mice ruled out a CB1-mediated effect. These results confirm that CB2 is present in the central nervous system and suggest that CB2 agonists may elicit their analgesic effect by acting not only at non-neuronal peripheral sites but also at neural level, making CB2 an attractive target for chronic pain treatment.


Assuntos
Analgésicos/farmacologia , Hiperalgesia/fisiopatologia , Fenômenos Fisiológicos do Sistema Nervoso , Receptor CB2 de Canabinoide/fisiologia , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Capsaicina/antagonistas & inibidores , Capsaicina/farmacologia , Células Cultivadas , Primers do DNA , DNA Complementar/biossíntese , DNA Complementar/genética , Formaldeído , Ligadura , Masculino , Camundongos , Microglia/fisiologia , Medição da Dor/efeitos dos fármacos , RNA/biossíntese , RNA/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Nervo Isquiático/fisiologia , Medula Espinal/citologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Nervos Espinhais/fisiologia , Transcrição Gênica
11.
Arch Gerontol Geriatr Suppl ; (9): 97-102, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15207403

RESUMO

Physicians often need to be able to assess cognition in a simple way, particularly for screening of subclinical processes in aged people. This paper describes a new, quick test battery called preventive-comprehensive assessment (PCA). It consists of six various testing items (repetition of three words, back-spelling of the word "sport", problem searching ina complex picture, recall of the three words, three progressive colored matrices, clock drawing test), evaluating language, recent memory, executive function, judgment and thinking capacities. The total scores. compared to the normal performance of different age groups, allow us to distinguish between normal and pathological status. If abnormal results are recorded, we need to perform further and deeper neuropsychological investigations, in order to obtain the possibly exact diagnosis. The PCA battery is sensitive and reliable; it can be used in itself, or as a part of a more complex battery of an intense comprehensive evaluation (ICE), carried out in population screening aimed at promoting healthy and active aging.


Assuntos
Transtornos Cognitivos , Programas de Rastreamento/métodos , Testes Neuropsicológicos , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/prevenção & controle , Estudos de Coortes , Demografia , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Vocabulário
12.
Int J Mol Med ; 14(1): 93-100, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15202022

RESUMO

We report on the characterization of the lipid obtained from cortical and medullary normal human kidney tissue, benign renal neoplasms (oncocytoma) and 2 different types of malignant renal neoplasms (chromophobic cell carcinoma and clear cell carcinoma). The total lipid fractions were analyzed by 13C magnetic resonance spectroscopy and thin-layer chromatography, whereas the composition of the total fatty acids and the content of total cholesterol were determined by gas chromatography. alpha-Tocopherol was detected and quantified by high-performance liquid chromatography. The spectroscopic and chromatographic analysis revealed significant differences in the renal tissues examined. It was confirmed that cholesteryl esters (mainly oleate) are typical of clear cell renal carcinomas. Their potential role as prognostic and diagnostic factors is discussed, with particular emphasis on its capability to indicate the tumor diffusion in healthy renal parenchyma. alpha-Tocopherol is prevalent in clear cell carcinoma and it is present in nearly the same low amounts in cortex, medulla and chromophobic cell renal carcinoma. Q10 coenzyme and dolichols were detected by thin-layer chromatography and they are present in significant amounts in the cortex and the benign oncocytoma. Great variations were found in the distribution of saturated and unsaturated fatty acids, especially in the docosapentaenoic, docosahexaenoic and arachidonic acids and the corresponding omega-6/omega-3 fatty acids ratio.


Assuntos
Neoplasias Renais/química , Lipídeos/análise , Cromatografia , Humanos , Espectroscopia de Ressonância Magnética , alfa-Tocoferol/análise
13.
Int J Mol Med ; 12(1): 99-102, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12792817

RESUMO

Lipids extracted from three human renal neoplasms have been characterized by means of 13C magnetic resonance spectroscopy. The presence of free cholesterol, high levels of unsatured fatty acids, and phosphatidylcholine, and a very high fatty acids/cholesterol ratio makes the lipid profile of a rare chromophobe cell carcinoma very similar to that of an oncocytoma. On the contrary, clear cell carcinomas are mainly characterized by the presence of almost fully esterified cholesterol and by a markedly lower level of unsatured fatty acids. Since chromophobic cell carcinomas have a more favourable prognosis than clear cell carcinomas, their analogy in the lipid composition with a benign renal neoplasm could have a clinical significance. In particular, our report suggests that cholesteryl esters and high levels of unsatured fatty acids could be a marker of a poor (clear cell carcinomas) or a good (chromophobic cell carcinomas) prognosis, respectively. More in depth studies are required of the molecular composition of the neoplastic pathologies that add new knowledge, with potential clinical implications.


Assuntos
Carcinoma de Células Renais/química , Ésteres do Colesterol/química , Idoso , Carcinoma de Células Renais/classificação , Carcinoma de Células Renais/fisiopatologia , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade
14.
Biopolymers ; 72(2): 86-95, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12583011

RESUMO

Lipids from human renal tissues are studied by means of (1)H- and (13)C-NMR spectroscopy. The total lipid fractions obtained from healthy kidneys, malignant renal cell carcinomas, and benign oncocytomas are characterized and analyzed to elucidate the main differences between the functional and neoplastic tissues. In all cases the lipid components are well identified. The healthy kidney is characterized by high amounts of triglycerides and the presence of cholesterol in its free form. On the contrary, renal cell carcinomas contain high amounts of cholesterol that are almost completely esterified as oleate, suggesting an intracellular localization of the cholesteryl esters synthesis. Cholesteryl esters are considered markers of renal cell carcinomas, thus supporting recent theories that these compounds play a leading role in cell proliferation. Oncocytomas are particularly rich in phosphatidylcholine and, analogous to the healthy kidney, are completely lacking in cholesteryl esters. Healthy kidneys and oncocytomas appear to have other similarities if compared with renal cell carcinomas: a very high fatty acyl/cholesterol ratio, the presence of dolichols, and a higher grade of unsaturation. The (13)C data suggest a new method for the direct evaluation of the saturated/unsaturated fatty acyl ratio.


Assuntos
Rim/química , Lipídeos/análise , Espectroscopia de Ressonância Magnética/métodos , Carcinoma de Células Renais/química , Humanos , Lipídeos/química
15.
Int J Mol Med ; 11(1): 95-8, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12469226

RESUMO

Cholesteryl esters (CholE) were detected in human malignant neoplasms by means of in vitro nuclear magnetic resonance spectroscopy. Spectroscopic analysis of the total lipid extracts obtained from cerebral tumors revealed appreciable amount of esterified cholesterol in high grade gliomas such as glioblastomas and anaplastic oligodendrogliomas, characterized by prominent neovascularity. The finding that no CholE were detected in the healthy brain and in low grade and benign tumors supports a possible correlation between this class of lipids and histological vascular proliferation. Compared with high grade gliomas, renal cell carcinomas show higher levels of CholE, absent in the healthy renal parenchyma and in benign oncocytomas. In nefro-carcinomas, cytoplasmic lipid inclusions and prominent vascularization contribute to the increased levels of CholE present mainly as oleate. CholE are discussed as potential biochemical markers of cancer and as a target for new therapeutic strategies.


Assuntos
Neoplasias Encefálicas/patologia , Ésteres do Colesterol/análise , Biópsia , Neoplasias Encefálicas/cirurgia , Glioma/patologia , Glioma/cirurgia , Humanos , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Espectroscopia de Ressonância Magnética , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/patologia , Meningioma/cirurgia , Oligodendroglioma/patologia , Oligodendroglioma/cirurgia
16.
Magn Reson Imaging ; 20(6): 479-86, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12361795

RESUMO

The origin and fate of cortical ischemic lesions, showing a stratified appearance at in vivo MRI-examination, was studied on rats in which a focal brain ischemia was induced by occlusion of the middle cerebral artery. One week after ischemia induction, six rats were selected in which three layers of different intensity were visible in the lesioned cortex. Two animals were sacrificed and studied by histology and electron microscopy. The external hyperintense layer was composed of pial and lesioned nervous tissue, the intermediate of degenerating nervous tissue in which an accumulation of macrophages was found, the deepest of edematous nerve tissue without a marked accumulation of macrophages. The remaining rats underwent further MRI examinations showing that, in the lesioned areas, cerebral blood volume was 14-69% lower than the contralateral healthy cortex. At histological and ultrastructural examination, a large part of the lesion was occupied by enlarged pial tissue and marginal glia. A dilatation of the ventricular cavity and cystic structures were also visible. In three animals an increase of the transverse diameter of the caudo-putamen ipsilateral to the lesion was found. The study suggests that the layered appearance is mainly due to an accumulation of macrophages in the intermediate layer and that several processes contribute to the occlusion of the space created by the removal of the necrotic tissue in stratified ischemic lesions (i.e. expansion of the pial tissue, thickening of the marginal glia; expansion of the caudo-putamen, enlargement of the ventricular cavity and development of cystic structures).


Assuntos
Isquemia Encefálica/diagnóstico , Córtex Cerebral/ultraestrutura , Imageamento por Ressonância Magnética , Animais , Volume Sanguíneo , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/patologia , Circulação Cerebrovascular , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Ratos , Ratos Sprague-Dawley
17.
Int J Mol Med ; 9(3): 299-310, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11836637

RESUMO

The clinical impact of (1)H NMR spectroscopy in the study of human organs, brain and kidney in particular, is well demonstrated. The in vitro (1)H NMR technique is a powerful tool for monitoring changes in intracellular metabolites of human normal and neoplastic cerebral and renal tissues. Healthy and tumoral tissues of different histologic types have been fully characterized from a biochemical standpoint. Molecular characterization is performed on both the aqueous and lipid extracts of surgically removed tissue biopsies yielding a full picture of tissue biochemistry. These analyses have disclosed markers of healthy brain and kidney and of their respective neoplastic lesions. Moreover, some biochemical features can differentiate neoplasms within the same histological type. In particular, lipidic components, like cholesteryl esters (namely oleate), detected in highest grade tumors, warrant further investigation. A better understanding of the biochemistry of diseased human tissues could open the way to new diagnostic and treatment strategies.


Assuntos
Neoplasias Encefálicas/química , Neoplasias Renais/química , Rim/química , Espectroscopia de Ressonância Magnética , Telencéfalo/química , Humanos , Lipídeos/química
19.
J Neurosci Methods ; 109(1): 59-70, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11489301

RESUMO

Recently, voltammetry with carbon fibre electrodes (CFE) has been implemented for real time measurement of nitrogen monoxide (NO) indicating that it is oxidised at the potential value of nitrites, approximately +700 mV. In contrast, here we show that modified CFE can monitor NO at oxidation potentials different than that of nitrites, i.e. +550 mV. Indeed, at +550 mV a significant increase of amperometric current levels was obtained when NO but not nitrites, were added to a phosphate buffer saline solution (PBS). Differential pulse voltammetry (DPV) supports these findings as two oxidation peaks were obtained when examining air preserved NO; peak 1 at +550 mV and peak 2 at +700 mV, respectively. In contrast, only peak 2 was monitored when nitrites or a solution of NO oxidised in air was added to PBS. Biological support to these in vitro data comes from the observation that the relaxation of an adrenaline-contracted aortic ring produced via addition of NO is concomitant with peak 1 at +550 mV. The relaxation is almost completed before the appearance of peak 2 at +700 mV. Furthermore, in vivo experiments performed in the striatum of rats show that the amperometric signal monitored at +550 mV is responsive to glutamatergic stimulation or inhibition of NO synthase.


Assuntos
Carbono , Eletrofisiologia/métodos , Potenciais da Membrana/fisiologia , Microeletrodos/tendências , Neuroquímica/métodos , Óxido Nítrico/análise , Nitritos/análise , 2-Amino-5-fosfonovalerato/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Carbono/normas , Fibra de Carbono , Eletrofisiologia/instrumentação , Inibidores Enzimáticos/farmacologia , Epinefrina/farmacologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Masculino , Microeletrodos/normas , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , N-Metilaspartato/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Neostriado/efeitos dos fármacos , Neostriado/metabolismo , Neuroquímica/instrumentação , Ratos , Ratos Wistar
20.
Eur J Pharmacol ; 419(2-3): 147-53, 2001 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-11426836

RESUMO

The neuroprotective activity of GV150526 (3-[2-(Phenylaminocarbonyl)ethenyl]-4,6-dichloroindole-2-carboxylic acid sodium salt), a selective glycine receptor antagonist of the NMDA receptor, has been evaluated by magnetic resonance imaging (MRI) in a rat model of middle cerebral artery occlusion. The aim of the work was to evaluate, using an in vivo method, whether GV150526 was able to reduce the extent of ischemic brain damage when administered both before and after (6 h) middle cerebral artery occlusion. GV150526 was administered at a dose of 3 mg/kg i.v. T2-weighted (T2W) and diffusion weighted (DW) images were acquired at 6, 24 and 144 h after the establishment of the cerebral ischemia. Substantial neuroprotection was demonstrated at all investigated time points when GV150526 was administered before the ischemic insult. The ischemic volume was reduced by 84% and 72%, compared to control values, when measured from T2W and DW images, acquired 24 h after middle cerebral artery occlusion. Administration of the same dose of GV150526, 6 h post-ischemia, also resulted in a significant (p < 0.05) neuroprotection. The ischemic volume was reduced by 48% from control values when measured from T2W images and by 45% when measured from DW images. No significant difference was found between volumes of brain ischemia obtained by either MRI or triphenyltetrazolium chloride staining. These data confirm the potential neuroprotective activity of the glycine receptor antagonist GV150526 when administered either before or up to 6 h after ischemia.


Assuntos
Isquemia Encefálica/prevenção & controle , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Indóis/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Receptores de Glicina/antagonistas & inibidores , Animais , Isquemia Encefálica/patologia , Imageamento por Ressonância Magnética , Masculino , Ratos , Ratos Sprague-Dawley
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