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31.
To date, research has led to the invention of multiple genes and their single nucleotide polymorphisms (SNPs) and environmental factors that influence the prostate cancer (PCa) pathogenesis. Therefore, the genes involved in these pathways are candidates for PCa predisposition. It is thought that polymorphisms of 5alpha-reductase II (SRD5A2) and 17 hydroxylase (CYP17) genes are likely to increase susceptibility. The aim of this study was to investigate the risk association of SRD5A2 and CYP17 gene polymorphisms in the development and progression of PCa in the Turkish population. In this study, 100 PCa patients and 105 healthy controls were studied. SRD5A2 and CYP17 gene polymorphisms were determined by real-time PCR and polymerase chain reaction-restriction length polymorphisms (PCR-RFLP) techniques. First, the AT and TT genotypes of SRD5A2 gene at codon 49 were not observed. Second, there was no significant association between the polymorphisms at codon 89 and the risk of PCa. Third, in the CYP17 gene, the A1A1 genotype is more common (46%) in cases than controls (32.4%). The odds ratios (ORs) of the A1A1 genotype was found at 1.69 (95% confidence interval [CI], 0.77-3.74) compare with the A2A2 genotype. Genotyping results of the SRD5A2 and CYP17 genes were also analyzed in relation to prostate-specific antigen (PSA) levels, Gleason score (GS), and tumor stage, but no statistically significant difference was observed (P > 0.05). Finally, we conclude that there was no evidence of an association between CYP17 (P = 0.134) and SRD5A2 (P = 0.784) polymorphism and PCa risk in the Turkish population. 相似文献
32.
The most common form of diabetes, type 2 diabetes (T2D) is a major Public Health issue which is receiving a great deal of attention both in industrial and public research, in order to develop new and more effective drugs. The hyperglycaemia of T2D is the result of two interdependent defects : decreased biological efficacy of insulin in target tissues (insulin resistance), and a decreased capacity for beta cells to secrete insulin in response to glucose. Furthermore, hyperglycaemia evolves with time and even with rigorous treatment there is a progressive deterioration of glucose homeostasis. Seventy five percent of DT2 patients are obese and show a perturbed lipid profile. beta-cell plasticity is a unique property of these cells to adapt their number and volume (beta-cell mass) and their function to the increased secretory demand linked to insulin resistance. This is well documented in physiological (pregnancy) as well in pathophysiological conditions (obesity, acromegaly). Although the lack of reliable techniques makes it very difficult to document it in humans, this property is likely altered in DT2, mainly as a consequence of the prolonged exposure of islet cells to high plasma levels of glucose and free fatty acids (gluco-lipotoxicity). The mechanisms by which hyperglycaemia and hyperlipidemia exert their deleterious effects on the beta-cell include the generation of Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS) and Advanced Glycosylation End Products (AGE). Altogether the prevailing clinical and experimental data urge us to consider that the pathophysiology of DT2 lies, at least in part, the inability of beta-cells to adapt their functional mass to the prevailing insulin demand. This re-evaluation of the pathophysiology of DT2 stimulates the research of new therapeutic approaches aimed at maintaining and/or restoring the functional beta-cell mass by targeting the mechanisms responsible for its decrease. 相似文献
33.
The lyophilized biomass of White rot fungi (Phanerochaete chrysosporium ME446) was immobilized in gelatine using glutaraldehyde crosslinking agent on a Pt working electrode. The fungal cells retained their laccase activity under entrapped state. The immobilized cells were used as a source of laccase to develop amperometric epinephrine biosensor. The catalytic action of the laccase in the biosensor released an epinephrinequinone as a result of redox activity, thereby causing an increase in the current. The optimal working conditions of the biosensor were carried out at pH 4.5 (50 mM acetate buffer containing 100 mM K(3)Fe(CN)(6)), and 20°C. The sensor response was linear over a range of 5-100 μM epinephrine. The detection limit of the biosensor was found to be 1.04 μM. In the optimization and characterization studies of the microbial biosensor some parameters such as effect of fungi and gelatine amount, percentage of glutaraldehyde on the biosensor response and substrate specificity were carried out. In the application studies of the biosensor, sensitive determination of epinephrine in pharmaceutical ampules was investigated. 相似文献
34.
Schmidt RG Bayburt EK Latshaw SP Koenig JR Daanen JF McDonald HA Bianchi BR Zhong C Joshi S Honore P Marsh KC Lee CH Faltynek CR Gomtsyan A 《Bioorganic & medicinal chemistry letters》2011,21(5):1338-1341
Novel chroman and tetrahydroquinoline ureas were synthesized and evaluated for their activity as TRPV1 antagonists. It was found that aryl substituents on the 7- or 8-position of both bicyclic scaffolds imparted the best in vitro potency at TRPV1. The most potent chroman ureas were assessed in chronic and acute pain models, and compounds with the ability to cross the blood-brain barrier were shown to be highly efficacious. The tetrahydroquinoline ureas were found to be potent CYP3A4 inhibitors, but replacement of bulky substituents at the nitrogen atom of the tetrahydroisoquinoline moiety with small groups such as methyl can minimize the inhibition. 相似文献
35.
36.
Tunçel N Sener E Cerit C Karasu U Gürer F Sahintürk V Bayçu C Ak D Filiz Z 《Peptides》2005,26(5):827-836
In the present study, the effect of systemically administered vasoactive intestinal peptide (VIP) (25 ng/kg i.p.) was investigated on drug-induced rotational behavior, extra-cellular dopamine levels and histology of corpus striatum in a 6-hydroxydopamine (6-OHDA)-induced rat model of Parkinson's disease. After 15 days of 6-OHDA lesion, apomorphine-induced (0.05 mg/kg s.c.) rotational behavior of the animals significantly increased and extra-cellular dopamine levels of corpus striatum were significantly reduced. VIP reversed the rotational deficits but did not alter the decrease in striatal dopamine levels. On the other hand, histological data indicate that VIP significantly reduced neuronal death and demyelination. Electron microscopic appearance of mast cells showed ultra-structural variety between VIP-treated and 6-OHDA lesioned groups. VIP activates mast cells without any evidence of typical exocytosis, and possibly mast cells could participate in neuroprotection. Our results suggest that systemically administered VIP can attenuate the motor response changes, neuronal cell death, and myelin sheet loss characteristically associated with 12 microg 6-OHDA administration into the rat striatum. Brain mast cells seem to participate in neuronal protection. Possibly, protective cues could be produced by brain mast cells. 相似文献
37.
Glass EJ Preston PM Springbett A Craigmile S Kirvar E Wilkie G Brown CG 《International journal for parasitology》2005,35(3):337-347
Disease-resistant livestock could provide a potentially sustainable and environmentally sound method of controlling tick and tick-borne diseases of livestock in the developing world. Advances in the knowledge and science of genomics open up opportunities to identify selectable genes controlling disease resistance but first, breeds and individuals with distinguishable phenotypes need to be identified. The Bos indicus breed, Sahiwal, has been exploited in dairy breeding programmes, because it is resistant to ticks and has relatively good performance characteristics compared to other indigenous cattle breeds of tropical regions. The analyses reported here show that Sahiwal calves were also more resistant than European Bos taurus (Holstein) dairy breed calves to tick-borne tropical theileriosis (Theileria annulata infection). Following experimental infection with T. annulata sporozoites, a group of Sahiwal calves all survived without treatment, with significantly lower maximum temperatures (P<0.01) and lower rates of parasite multiplication (P<0.05) than a group of Holstein calves, which all had severe responses. Although the Sahiwals became as anaemic as the Holsteins, other measures of pathology, including enlargement of the draining lymph node and the acute phase proteins, alpha1 acid glycoprotein and haptoglobin, were significantly less in the Sahiwals than in the Holsteins (P<0.05). Additionally, the Sahiwals had significantly lower resting levels of alpha1 acid glycoprotein than the Holsteins (P<0.05). Production of a third acute phase proteins, serum amyloid A, had very similar kinetics in both breeds. Acute phase proteins are produced in response to systemic release of the kinds of pro-inflammatory cytokines that are thought to be responsible for the pyrexic, cachectic and anorexic responses characteristic of tropical theileriosis. The prolonged production of alpha1 acid glycoprotein in the Holsteins is indicative of chronic production of circulating pro-inflammatory cytokines. In contrast, Sahiwals appear able to overcome infection with T. annulata as well as limit pathology by preventing the over-stimulation of pathways involving these cytokines. 相似文献
38.
The Hallermann-Streiff syndrome is characterized by bird-like face, micropthalmia, cataracts, micrognathia, beaked nose, abnormal dentition, hypotrichosis, cutaneous atrophy and proportional small stature. We present a 35-day-old patient with the classical signs except cutaneous atrophy, additionally he had a healing fracture at the proximal part of the left radius. 相似文献
39.
Saygili E Rana OR Günzel C Rackauskas G Saygili E Noor-Ebad F Gemein C Zink MD Schwinger RH Mischke K Weis J Marx N Schauerte P 《Cellular signalling》2012,24(1):99-105
An irregular ventricular response during atrial fibrillation (AF) has been shown to mediate an increase in sympathetic nerve activity in human subjects. The molecular mechanisms remain unclear. This study aimed to investigate the impact of rate and irregularity on nerve growth factor (NGF) expression in cardiomyocytes, since NGF is known to be the main contributor to cardiac sympathetic innervation density. Cell cultures of neonatal rat ventricular myocytes were electrically stimulated for 48 h with increasing rates (0, 5 and 50 Hz) and irregularity (standard deviation (SD) = 5%, 25% and 50% of mean cycle length). Furthermore, we analyzed the calcineurin-NFAT and the endothelin-1 signalling pathways as possible contributors to NGF regulation during arrhythmic stimulation. We found that the increase of NGF expression reached its maximum at the irregularity of 25% SD by 5 Hz (NGF: 5 Hz 0% SD = 1 vs. 5 Hz 25% SD = 1.57, P < 0.05). Specific blockade of the ET-A receptor by BQ123 could abolish this NGF increase (NGF: 5 Hz 25% SD + BQ123 = 0.66, P < 0.05). High frequency electrical field stimulation (HFES) with 50 Hz decreased the NGF expression in a significant manner (NGF: 50 Hz = 0.55, P < 0.05). Inhibition of calcineurin-NFAT signalling with cyclosporine-A or 11R-VIVIT abolished the HFES induced NGF down-regulation (NGF: 50 Hz + CsA = 1.14, P < 0.05). In summary, this study reveals different signalling routes of NGF expression in cardiomyocytes exposed to increasing rates and irregularity. Whether this translates into different degrees of NGF expression and possibly neural sympathetic growth in various forms of ventricular rate control during AF remains to be elucidated in further studies. 相似文献
40.
Kaltenpoth M Yildirim E Gürbüz MF Herzner G Strohm E 《Applied and environmental microbiology》2012,78(3):822-827
Insects engage in symbiotic associations with a large diversity of beneficial microorganisms. While the majority of well-studied symbioses have a nutritional basis, several cases are known in which bacteria protect their host from pathogen infestation. Solitary wasps of the genera Philanthus and Trachypus (beewolves; Hymenoptera, Crabronidae) cultivate the actinomycete "Candidatus Streptomyces philanthi" in specialized antennal gland reservoirs. The symbionts are transferred to the larval cocoon, where they provide protection against pathogenic fungi by producing at least nine different antibiotics. Here we investigated the closest relatives of Philanthus and Trachypus, the rare genus Philanthinus, for the presence of antennal gland reservoirs and symbiotic streptomycetes. Molecular analyses identified "Ca. Streptomyces philanthi" in reservoirs of Philanthinus quattuordecimpunctatus. Phylogenies based on the 16S rRNA gene suggest that P. quattuordecimpunctatus may have acquired "Ca. Streptomyces philanthi" by horizontal transfer from other beewolf species. In histological sections and three-dimensional reconstructions, the antennal gland reservoirs were found to occupy six antennal segments (as opposed to only five in Philanthus and Trachypus) and to be structurally less complex than those of the evolutionarily more derived genera of beewolves. The presence of "Ca. Streptomyces philanthi" in antennal glands of Philanthinus indicates that the symbiosis between beewolves and Streptomyces bacteria is much older than previously thought. It probably evolved along the branch leading to the monophyletic tribe Philanthini, as it seems to be confined to the genera Philanthus, Trachypus, and Philanthinus, which together comprise 172 described species of solitary wasps. 相似文献