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41.
Parviz Ghadirian PhD Bryna Shatenstein Maurice Verdy Pavel Hamet 《European journal of epidemiology》1995,11(3):275-281
Elevated levels of plasma uric acid have been linked to increased risk of cardiovascular diseases and their complications. As dairy proteins have been found to decrease plasma uric acid without increasing glomerular filtration rate, a sample of postmenopausal women living in Montreal was studied to investigate the nature of this relationship. Participants (158 Roman Catholic nuns) were randomly assigned to one of two test diets for a period of four weeks: the dairy foods group (n=81) consumed approximately 30 grams of dairy protein daily and the dairy-free diet group (n=77) ate no dairy foods at all. Subjects completed two one-day food records, a core questionnaire and a dairy foods diet history; blood specimens were obtained, and blood pressure, height and weight were measured. Average nutrient intakes differed as a consequence of the test diets, with significantly greater intakes of protein, fat, saturated fat, monounsaturated fat, potassium and calcium (p<0.01) in the dairy group after the study period, and lower dietary levels of protein, cholesterol, calcium and retinol (p<0.01) in the dairy-free group. Plasma uric acid was unchanged after the dietary intervention in the dairy group, but increased by 7.8 µmol/1 (p=0.03) in subjects on the dairy-free diet; however, diastolic blood pressure decreased in response to calcium (=–22.9, SE=10.0,p=0.02) among those whose diet included dairy foods. The study results suggest that proteins of dairy origin may play a role in stabilising or lowering plasma uric acid, and that calcium or other components found in milk products may also reduce diastolic blood pressure. While these findings have implications for dietary prevention to decrease cardiovascular risk in postmenopausal women, further investigations should examine these mechanisms in men over the age of 50 to ascertain whether a similar response would occur. 相似文献
42.
Foia L Costuleanu N Trandafirescu M Saila V Pavel M 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》1999,103(3-4):69-73
Provision of a better understanding of the pathogenic pathways underlying injured sugar metabolism during stress should ideally translate into a more rational approach to the provision of nutritional support. Patients with burns, trauma, severe injuries or infections commonly develop a hypermetabolic state that is associated with several changes in carbohydrate metabolism. The hypermetabolic state is induced either by the area of injury and by organs involved in the immunologic response to stress; further it determines a glycemic milieu which will be directed toward satisfaction of the requirements for glucose as an energy support. 相似文献
43.
Jan Vondrácek Miroslav Machala Vítezslav Bryja Katerina Chramostová Pavel Krcmár Cornelia Dietrich Ales Hampl Alois Kozubík 《Toxicological sciences》2005,83(1):53-63
Polychlorinated biphenyls (PCBs) exhibit tumor-promoting effects in experimental animals. We investigated effects of six model PCB congeners and hydroxylated PCB metabolites on proliferation of contact-inhibited rat liver epithelial WB-F344 cells. The 'dioxin-like' PCB congeners, PCB 126, PCB 105, and 4'-OH-PCB 79, a metabolite of the planar PCB 77 congener, induced cell proliferation in a concentration-dependent manner. In contrast, the 'non-dioxin-like' compounds that are not aryl hydrocarbon receptor (AhR) agonists, PCB 47, PCB 153, and 4-OH-PCB 187, an abundant noncoplanar PCB metabolite, had no effect on cell proliferation at concentrations up to 10 muM. The concentrations of dioxin-like PCBs leading to cell proliferation corresponded with the levels inducing the expression of cytochrome P450 1A1 mRNA, suggesting that the release from contact inhibition was associated with AhR activation. The effects of PCB 126 and PCB 153 on expression of proteins controlling G0/G1-S-phase transition and S-phase progression were compared. Only PCB 126 was found to upregulate cyclin A and D2 protein levels, and to increase both total cyclin-dependent kinase 2 (cdk2) and cyclin A/cdk2 complex activities. Despite the observed upregulation of cyclin D2, no increase in cdk4 activity was observed. The expression of cdk inhibitor p27Kip1 was not affected by either PCB 126 or PCB 153. These results suggest that dioxin-like PCBs can induce cell proliferation of contact-inhibited rat liver epithelial cells by increasing cyclin A protein levels, a process that then leads to upregulation of cyclin A/cdk2 activity and initiation of DNA replication. This mechanism could be involved in tumor-promoting effects of dioxin-like PCBs. 相似文献
44.
Sanguinarine and chelerythrine: assessment of safety on pigs in ninety days feeding experiment. 总被引:4,自引:0,他引:4
Pavel Kosina Daniela Walterová Jitka Ulrichová Václav Lichnovsky Marie Stiborová Helena Rydlová Jaroslav Vicar Vladimír Krecman Michael J Brabec Vilím Simánek 《Food and chemical toxicology》2004,42(1):85-91
Sanguinaria canadesis, Chelidonium majus and Macleya cordata have been used for centuries as alternative medicines. Currently the extracts from these medicinal plants are components of veterinary and human phytopreparations, and of oral-hygiene agents. Sanguinarine and chelerythrine (SA/CHE) are biologically active components of these extracts. They display distinct antibacterial and anti-inflammatory properties, but, on the other hand, they have been reported as having adverse effects - genotoxicity and hepatotoxicity. This paper is aimed at evaluation of the effects of daily administration of the extract from Macleya cordata (2 mg and 100 mg in 1 kg feed, sanguinarine:chelerythrine 3:1) in the diet on the health status of swine. After 90-day administration, alkaloids were retained to a different extent in tissues. The highest SA/CHE retention was detected in the gingiva (0.55 microg/g) and liver (0.15 microg/g), no SA/CHE were detected in muscles. Plasma SA levels attained 0.11 microg/ml. Treated animals did not display any results of hematological, biochemical or histological assay different from controls. A (32)P-postlabeling assay proved that no DNA-adducts with SA/CHE were detected in pig livers. We did not observe any symptom linked to epidemic dropsy syndrome often attributed to sanguinarine. In conclusion, an average daily oral dose of alkaloids up to 5 mg per 1 kg animal body weight proved to be safe. 相似文献
45.
Mateja Kaja Jezovnik Nina Zidar Luka Lezaic Borut Gersak Pavel Poredos 《Inflammation》2014,37(2):426-434
Inflammation plays a major pathogenetic role in the development of atherosclerotic plaques and related thromboembolic events. The identification of vulnerable plaques is of the utmost importance, as this may allow the implementation of more effective preventive and therapeutic interventions. Fluorodeoxyglucose positron emission tomography (FDG-PET) has been shown to be useful for tracing inflammation within plaques. However, its relationship to immunohistochemical findings in different territories of the peripheral circulation was not completely elucidated. We aimed to determine whether plaque inflammation could be measured by PET in combination with computer tomography (CT) using FDG and what is the relationship between FDG uptake and immunohistochemical findings in the removed atherosclerotic lesions of the femoral and carotid arteries. The study included 31 patients, 21 patients with high-grade stenosis of the internal carotid artery (ICA) and 10 patients with occlusion of the common femoral artery (CFA), all of whom underwent endarterectomy. Before endarterectomy in all patients, FDG-PET/CT imaging was performed. FDG uptake was measured as the maximum blood—normalized standardized uptake value, known as the target to background ratio (TBR max). TBR max amounted to 1.72?±?0.8, and in patients with ICA, stenosis was not significantly different from patients with CFA occlusion. Immunohistochemical and morphometric analyses of the plaques obtained at endarterectomy showed that the density of T lymphocytes and macrophages (number of cells per square millimeter) was significantly higher in subjects with stenosis of the ICA than in subjects with occlusion of the femoral arteries: lymphocytes, 1.26?±?0.21 vs. 0.77?±?0.29; p?=?0.02 and macrophages, 1.01?±?0.18 vs. 0.69?±?0.23; p?=?0.003. In the whole group of patients, the density of inflammatory cells significantly correlated with FDG uptake represented by PET-TBR max: T lymphocytes, r?=?0.60; p?<?0.01 and macrophages, r?=?0.65; p?<?0.01. The results of our study show that FDG uptake is related to the accumulation of inflammatory cells in atherosclerotic lesions. This finding suggests that FDG uptake reflects the severity of atherosclerotic vessel wall inflammation, and in stenotic lesions, it could be an indicator of their vulnerability. However, data from large outcome studies is needed to estimate the usefulness of this technique in identifying the most dangerous atherosclerotic lesions and vulnerable patients. 相似文献
46.
47.
正Aging is well known to be the main risk factor for the neurodegenerative pathologies,in particular,Parkinson’s disease(PD)and Alzheimer’s disease(AD).In aging and in the diseases,similar changes in various hallmarks of neurodegeneration(lipofuscin accumulation,autophagia weakening,and disturbances in functions of mitochondria 相似文献
48.
Pavel Mareš 《Naunyn-Schmiedeberg's archives of pharmacology》2014,387(8):753-761
Ifenprodil, an antagonist of NMDA receptors containing the NR2B subunit, was expected to exhibit anticonvulsant action in rat pups up to the third postnatal week because of predominance of NR2B subunit at early development. Cortical epileptic afterdischarges (ADs) were used to study possible effects on threshold current intensities and duration of ADs in 12-, 15-, 18-, and 25-day-old rats. A series of 18 stimulation series with stepwise increasing current intensities (from 0.2 to 15 mA) was applied with 10-min intervals. The first experiment studied rats pretreated with ifenprodil (20 or 40 mg/kg), the second experiment studied an effect of ifenprodil on already present ADs—the dose of 20 mg/kg was administered after stimulation with the 3.5-mA current intensity. Pretreatment with ifenprodil resulted in an anticonvulsant effect in 15-day-old rats only, on the contrary, proconvulsant action was found in 18- and 25-day-old animals (decrease of thresholds especially for transition into the second, limbic type of ADs and increase in duration of ADs). Anticonvulsant effect was found in 12-, 15-, and 18-day-old rats in the second experiment—ADs were shortened. In contrast, no effect was observed in 25-day-old animals. An anticonvulsant action of ifenprodil is not only age-dependent but also activation-dependent. 相似文献
49.
Mitochondrial membrane protein-associated neurodegeneration (MPAN) is an autosomal recessive disorder caused by mutation in the C19orf12 gene. We report a compound heterozygous c.[32C>T];[205G>A;424A>G] (p.[Thr11Met];[Gly69Arg;Lys142Glu]) Czech patient who manifested with right foot dystonia, impaired handwriting, attention deficit, and signs of iron accumulation on brain MRI. Gradually, he developed dysarthria, spastic-dystonic gait, pedes cavi, and atrophy of leg muscles. Additionally, we report demographic parameters, clinical signs, and allelic frequencies of C19orf12 mutations of all published MPAN cases. We compared the most frequent mutations, p.Thr11Met and p.Gly69ArgfsX10; the latter was associated with younger age at onset and more frequent optic atrophy in homozygotes. 相似文献