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1.
Biochimie ; 153: 80-85, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29730299

RESUMO

Cholesterol and its oxygenated metabolites, such as oxysterols, are intensively investigated as potential players in the pathophysiology of brain disorder. Altered oxysterol levels have been described in patients with numerous neuropsychiatric disorders, including Alzheimer's disease, Amyotrophic Lateral Sclerosis, Parkinson's disease, X-linked adrenoleukodystrophy, and Smith-Lemli-Opitz Syndrome. Recent studies have shown that Autism Spectrum Disorders are associated with disruption of cholesterol metabolism. The present study aimed at investigating the profile of oxysterols in plasma and their association with clinical parameters in patients with Autism Spectrum Disorders. Thirty-six children with Autism Spectrum Disorders and thirty-eight healthy children, from Sfax (a southern area of Tunisia) matched for age and sex, were included in the study. The severity of Autism Spectrum Disorders was evaluated using the childhood autism rating scale. Standard lipid profile (total cholesterol, triglycerides, and high-density lipoprotein-cholesterol), serum glucose, high-sensitive C-reactive protein and orosomucoid levels were measured utilizing standard techniques. Oxysterol levels were measured by isotope-dilution gas chromatography/mass spectrometry. Standard lipid profile, serum glucose, high-sensitive C-reactive protein and orosomucoid levels were similar between the two studied populations. Compared to the control group, children with Autism Spectrum Disorders showed a significant higher plasma level of 24-hydroxycholesterol, while borderline significance was observed for 7α-hydroxycholesterol, and 25-hydroxycholersterol. In patients, 24-hydroxycholesterol was inversely correlated with age. Multivariate analysis showed that high plasma levels of 24-hydroxycholesterol are independent risk factors for Autism Spectrum Disorders. On the other hand, an analysis of the receiver's operating characteristics proved that the measured parameters recorded satisfactory levels of specificity and sensitivity. The present study provides evidence that Autism Spectrum Disorders are associated with altered levels in circulating oxysterols. The finding that 24-hydroxycholesterol is an independent risk factor for the disease and suggests the use of this oxysterol as a diagnostic tool in Autism Spectrum Disorders.


Assuntos
Transtorno Autístico/sangue , Transtorno Autístico/diagnóstico , Hidroxicolesteróis/metabolismo , Oxisteróis/sangue , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Fatores de Risco
2.
Redox Biol ; 13: 581-587, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28783588

RESUMO

Oxysterols are bioactive lipids that act as regulators of lipid metabolism, inflammation, cell viability and are involved in several diseases, including atherosclerosis. Mounting evidence linked the atherosclerosis to endothelium dysfunction; in fact, the endothelium regulates the vascular system with roles in processes such as hemostasis, cell cholesterol, hormone trafficking, signal transduction and inflammation. Several papers shed light the ability of oxysterols to induce apoptosis in different cell lines including endothelial cells. Apoptotic endothelial cell and endothelial denudation may constitute a critical step in the transition to plaque erosion and vessel thrombosis, so preventing the endothelial damaged has garnered considerable attention as a novel means of treating atherosclerosis. Endoplasmic reticulum (ER) is the site where the proteins are synthetized and folded and is necessary for most cellular activity; perturbations of ER homeostasis leads to a condition known as endoplasmic reticulum stress. This condition evokes the unfolded protein response (UPR) an adaptive pathway that aims to restore ER homeostasis. Mounting evidence suggests that chronic activation of UPR leads to cell dysfunction and death and recently has been implicated in pathogenesis of endothelial dysfunction. Autophagy is an essential catabolic mechanism that delivers misfolded proteins and damaged organelles to the lysosome for degradation, maintaining basal levels of autophagic activity it is critical for cell survival. Several evidence suggests that persistent ER stress often results in stimulation of autophagic activities, likely as a compensatory mechanism to relieve ER stress and consequently cell death. In this review, we summarize evidence for the effect of oxysterols on endothelial cells, especially focusing on oxysterols-mediated induction of endoplasmic reticulum stress.


Assuntos
Estresse do Retículo Endoplasmático , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Oxisteróis/metabolismo , Animais , Apoptose , Autofagia , Endotélio Vascular/citologia , Humanos , Resposta a Proteínas não Dobradas
3.
Andrology ; 4(6): 1094-1101, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27673576

RESUMO

Previous reports showed altered fatty acid content in subjects with altered sperm parameters compared to normozoospermic individuals. However, these studies focused on a limited number of fatty acids, included a short number of subjects and results varied widely. We conducted a case-control study involving 155 patients allocated into four groups, including normozoospermia (n = 33), oligoasthenoteratozoospermia (n = 32), asthenozoospermia (n = 25), and varicocoele (n = 44). Fatty acid profiling, including 30 species, was analyzed by a validated gas chromatography (GC) method on the whole seminal fluid sample. Multinomial logistic regression modeling was used to identify the associations between fatty acids and the four groups. Specimens from 15 normozoospermic subjects were also analyzed for fatty acids content in the seminal plasma and spermatozoa to study the distribution in the two compartments. Fatty acids lipidome varied markedly between the four groups. Multinomial logistic regression modeling revealed that high levels of palmitic acid, behenic acid, oleic acid, and docosahexaenoic acid (DHA) confer a low risk to stay out of the normozoospermic group. In the whole population, seminal fluid stearic acid was negatively correlated (r = -0.53), and DHA was positively correlated (r = 0.65) with sperm motility. Some fatty acids were preferentially accumulated in spermatozoa and the highest difference was observed for DHA, which was 6.2 times higher in spermatozoa than in seminal plasma. The results of this study highlight complete fatty acids profile in patients with different semen parameters. Given the easy-to-follow and rapid method of analysis, fatty acid profiling by GC method can be used for therapeutic purposes and to measure compliance in infertility trials using fatty acids supplements.


Assuntos
Ácidos Graxos/análise , Infertilidade Masculina/metabolismo , Análise do Sêmen , Sêmen/química , Motilidade dos Espermatozoides/fisiologia , Adulto , Astenozoospermia/metabolismo , Estudos de Casos e Controles , Humanos , Masculino , Oligospermia/metabolismo , Varicocele/metabolismo , Adulto Jovem
4.
Clin Chim Acta ; 446: 156-62, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25916693

RESUMO

BACKGROUND: Assessing vitamin E status in humans is critical for nutritional evaluation and verification of clinical and biological compliance of supplemented subjects. An accurate analytical method for measuring the two main vitamin E isoforms, i.e. α- and γ-tocopherol (α- and γ-TOH) in small volumes of plasma can facilitate the application of this analysis to clinical trials and in situations where a limited amount of sample is available. METHODS: We have developed a micro method, which uses only 5 µL plasma, based on isotope dilution, trimethylsilation and GC-MS. The method was validated according to the guidelines of the International Conference on Harmonization of analytical procedures. The method was also applied to 5 µL of whole blood for the potential use in conditions were the availability of specimens is limited. RESULTS: Accurate quantitation of α-TOH and γ-TOH was achieved at levels ≥ 0.417 µM and ≥ 0.007 µM, respectively. Within-day coefficient of variation was 1.31% and 4.70% for α-TOH and γ-TOH, respectively. Between-day coefficient of variation was 1.32% and 2.88% for α-TOH and γ-TOH, respectively. Recovery, assessed at three concentration levels, ranged 98-103% and 100-102% for α-TOH and γ-TOH, respectively. The method allowed the detection of α-TOH and γ-TOH in 5 µL whole blood and in membranes of red blood cells washed from 5 µL of blood as well. The analytical performance was assessed in plasma from a cohort of Italian healthy subjects (n = 205). The mean plasma concentrations were 28.01 ± 6.31 and 0.68 ± 0.48 µM (mean ± SD) for α-TOH and γ-TOH, respectively. Alpha-TOH correlated with total cholesterol (r = 0.617, p < 0.0001) and triglycerides (r = 0.420, p < 0.0001) while γ-TOH correlated modestly with total cholesterol (r = 0.213, p < 0.0001) but not with triglycerides. γ-TOH, but not α-TOH, was significantly lower in smokers than in non-smokers (0.72 ± 0.50 vs. 0.56 ± 0.37, µM, mean ± SD, p = 0.017). Given the high sensitivity, the method allowed to be applied to 5 µM whole blood without specific modification. CONCLUSIONS: This micro-method represents an analytical advancement in α- and γ-TOH assay that is available to accurately verify the nutritional status and compliance after supplementation in large-scale settings, and to measure the two vitamers in conditions where sample availability is limited.


Assuntos
Antioxidantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , alfa-Tocoferol/sangue , gama-Tocoferol/sangue , Adulto , Glicemia/metabolismo , Feminino , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Técnica de Diluição de Radioisótopos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Triglicerídeos/sangue , Compostos de Trimetilsilil/química , Trítio
5.
Cell Mol Life Sci ; 61(15): 1965-74, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15289937

RESUMO

Human and rat primary sub-cultured vascular smooth muscle cells (VSMCs) showed clear expression of the death receptors TRAIL-R1 and TRAIL-R2; however, recombinant soluble TRAIL did not induce cell death when added to these cells. TRAIL tended to protect rat VSMCs from apoptosis induced either by inflammatory cytokines tumor necrosis factor-alpha + interleukin-1beta + interferon-gamma or by prolonged serum withdrawal, and promoted a significant increase in VSMC proliferation and migration. Of note, all the biological effects induced by TRAIL were significantly inhibited by pharmacological inhibitors of the ERK pathway. Western blot analysis consistently showed that TRAIL induced a significant activation of ERK1/2, and a much weaker phosphorylation of Akt, while it did not affect the p38/MAPK pathway. Taken together, these data strengthen the notion that the TRAIL/TRAIL-R system likely plays a role in the biology of the vascular system by affecting the survival, migration and proliferation of VSMCs.


Assuntos
Movimento Celular/fisiologia , Glicoproteínas de Membrana/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose , Artérias/metabolismo , Divisão Celular/fisiologia , Sobrevivência Celular/fisiologia , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/citologia , Ratos , Receptores do Ligante Indutor de Apoptose Relacionado a TNF , Receptores do Fator de Necrose Tumoral/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF
6.
Chir Ital ; 37(3): 250-62, 1985 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-4053245

RESUMO

Our study compares the results obtained through the assay of AT III following two methods, the functional and the immunological one, carried out on plasma of 222 patients affected with solid malignant neoplasia. The purpose of our research was to examine the behaviour of AT III, a protein having a peculiar function in the complex coagulation mechanism. At least among healthy people, this function was and is correlated to its blood concentration. All examined subjects suffered from solid malignant neoplasia either of the respiratory tract or gastro-intestinal tract or sexual organs or urinary tract. From our research patients with liver neoplasia diagnosis have been excluded since the cancer seat might have significant implications on the genesis of coagulation factors and therefore on AT III itself. The age of patients as well as controls - formed by 100 clinically healthy donors-ranged between 30 and 70. At the very beginning patients were divided into groups according to the basic pathology (cancer seat) but then, since no great differences were noted between the groups, all patients were examined irrespective of the type and seat of neoplasia. The followed methods are: a functional method which tends to measure the total AT III capacity assay acting in enzyme excess. S 2238 (Kabi) being the chromogene substratum used; an immunological method which tends to measure the molecule blood concentration taking advantage of its antigenic properties. While on one hand the obtained results have shown a good correlation between the two methods in controls i.c. healthy subjects, on the other hand a significant difference has been noted between the AT III activity and its blood concentration in non healthy subjects as if to prove the interference of neoplasia in the blood coagulation process. In the patients affected with neoplasia the functional as well as the quantitative aspect - which can be considered synonyms in healthy subjects being the one indicative of the other - show that the delicate balance on which the coagulation mechanism is based has been upset.


Assuntos
Antitrombina III/análise , Neoplasias/sangue , Adulto , Idoso , Compostos Cromogênicos , Dipeptídeos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Radioimunoensaio
7.
Chir Ital ; 37(1): 3-16, 1985 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-3995662

RESUMO

We have examined 222 patients with nonterminal solid malignant tumors in order to study the possible variations on the hemocoagulation system due to neoplasia. Only patients whose hemocoagulation system could be proven normal by test made before the malignant neoplasia appeared were taken into consideration. Our study was based on the following tests: platelet count, platelet adhesiveness and aggregation, prothrombin time, thrombin time, thrombotest, antithrombin 3, thrombin-coagulase, activity partial thromboplastin time, fibrinogen, reptilase time. Our study showed there was no relevant difference between the results tests of healthy people taken as points or reference and those of our patients. We did find however a slight but diffuse alteration of all, or almost all, the components of the hemostatic and coagulation system. These variations however were not significant enough to enable us to prove any connection between the neoplasia and the whole hemocoagulation system.


Assuntos
Coagulação Sanguínea , Neoplasias/sangue , Adulto , Idoso , Testes de Coagulação Sanguínea , Feminino , Hemostasia , Humanos , Masculino , Pessoa de Meia-Idade
8.
Radiol Med ; 70(7-8): 516-9, 1984.
Artigo em Italiano | MEDLINE | ID: mdl-6535170

RESUMO

Since anaemia of varying degree is a quite common finding in heterozygous beta-thalassaemia, a research was done to see if beta-thalassaemia heterozygotes occupationally exposed to long-term continuous external radiation should be more susceptible to haematopoietic damage than non thalassaemic subjects. We examined peripheral haematological findings of 20 beta-thalassaemia heterozygotes previously exposed to a mean of 10.7 mSv, compared with 22 non thalassaemic subjects exposed to 6 mSv, and with 50 not exposed beta-thalassaemia heterozygotes. The obtained results suggest that whole-body external irradiation--with the mean doses reported--does not cause noteworthy changes in beta-thalassaemia heterozygotes.


Assuntos
Doenças Profissionais/etiologia , Efeitos da Radiação , Talassemia/complicações , Adolescente , Adulto , Contagem de Células Sanguíneas , Exposição Ambiental , Feminino , Hematócrito , Hemoglobinometria , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Radiação Ionizante , Risco , Talassemia/sangue , Talassemia/genética
9.
Minerva Chir ; 34(8): 631-7, 1979 Apr 30.
Artigo em Italiano | MEDLINE | ID: mdl-460619

RESUMO

A survey of the main series in the world literature and personal data concerning injuries to the pancreas is followed by the suggestion that the risk of pseudocyst or pancreatitis means that in all cases where injury to the pancreas is suspected, and resolution is slow, laparotomy must be performed, coupled with careful exploration of the lesser omentum and precise evaluation of possible lesions, prior to suitable surgical management. Medical therapy is also of prime importance. Its main feature is the administration of a protease inhibitor to prevent pre- and post-operative enzymatic toxaemia.


Assuntos
Pâncreas/lesões , Adulto , Pré-Escolar , Drenagem , Duodeno/cirurgia , Humanos , Jejuno/cirurgia , Masculino , Pâncreas/cirurgia , Pancreatectomia , Fístula Pancreática/cirurgia , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Inibidores de Proteases/administração & dosagem , Inibidores de Proteases/uso terapêutico , Ferimentos por Arma de Fogo/cirurgia
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