ABSTRACT
Vitamin D receptor (VDR) gene single nucleotide polymorphisms (SNPs) have been investigated over the past years with the aim of identifying any association with the development of Alzheimer's disease (AD). However, information regarding the potential association of VDR SNP haplotypes with AD is limited. The aim of the present study was to provide additional knowledge on the effects of VDR haplotypes on the development of late-onset AD in a cohort of Southeastern European Caucasians (SECs). The study sample included 78 patients with late-onset AD and 103 healthy subjects as the control group. VDR SNPs that were analyzed were TaqI (rs731236), BsmI (rs1544410) and FokI (rs2228570). The CAC (TaqI, BsmI and FokI) haplotype was found to be associated with a 53% lower risk of developing the disease (OR, 0.47; 95% CI, 0.23-0.96; P=0.04) and the TAC (TaqI, BsmI and FokI) haplotype was associated with an ~6-fold greater risk of developing AD (OR, 6.19; 95% CI, 1.91-20.13; P=0.0028). Female subjects carrying the TAC haplotype had a ~9-fold greater risk of developing AD in comparison to female control subjects (OR, 9.27; 95% CI, 1.86-46.28; P<0.05). The TaqI and BsmI polymorphisms were in high linkage disequilibrium (D'=0.9717, r=0.8467) and produced a haplotype with a statistically significant different frequency between the control and AD group. The TA (TaqI and BsmI) haplotype was associated with an ~8-fold greater risk of developing AD (OR, 8.27; 95% CI, 2.70-25.28; P<0.05). Female TA carriers had an ~14-fold greater risk of developing the disease in comparison to female control subjects (OR, 13.93; 95% CI, 2.95-65.87; P<0.05). On the whole, the present study demonstrates that in the SEC population, TAC and TA are risk haplotypes for AD, while the CAC haplotype may act protectively. SEC women carrying the TAC or TA haplotype are at a greater risk of developing AD, thus suggesting that women are markedly affected by the poor utilization of vitamin D induced by the VDR haplotype.
ABSTRACT
The role of vitamin D in Alzheimer's Disease (AD) has been studied over the past years. The results from numerous studies have indicated that the molecular pathways involved in the development of AD are closely related to the molecular pathways of the mechanisms of action of vitamin D. However, only a limited number of studies have described the key role of vitamin D receptor (VDR) in the regulation of the functions of vitamin D and the potential effect of single nucleotide polymorphisms (SNPs) of the VDR gene. Thus, the aim of the present study was to investigate the VDR TaqI polymorphism in relation to AD in a Southeastern European Caucasian (SEC) cohort. Further, the present study aimed to compare the results obtained with those of other AD populations. For this purpose, blood samples from 90 confirmed patients with AD [median age, 74 years; median mini-mental state examination (MMSE) score of 21; median frontal assessment battery (FAB) score of 10] and 103 healthy controls (median age, 57 years) were analyzed to determine the genotypes of TaqI (rs731236) using quantitative PCR. The frequencies (%) of the TaqI TT, TC and CC genotypes in the controls/patients were 34/48.9, 47.6/41.1 and 18.4/10.0, respectively. Statistically significant differences were observed for the TaqI C allele [odds ratio (OR). 0.54; 95% confidence interval (CI), 0.30-0.96; P=0.035], the TaqI TT genotype (OR, 1.86; 95% CI, 1.04-3.32; P=0.035) and the TaqI CC genotype (OR, 0.119; 95% CI, 0.014-0.995; P=0.032,) in relation to the MMSE score <21 in the patient's group. The TaqI TT allele was found to increase the risk of developing AD by 1.86-fold in the SEC population, while the TaqI C allele may act protectively, with a 46% lower risk of developing the disease. Patients with the TaqI CC genotype were found to have an 88% less likelihood of developing severe cognitive impairment based on the MMSE score. On the whole, the present study did not confirm the results of previous studies on the VDR TaqI C allele in patients with AD.
ABSTRACT
Genetic polymorphisms in ß1-, ß2- and ß3-adrenergic receptors (ß-ARs) have been associated with chronic non-communicable disorders, such as cardiovascular diseases, asthma, chronic obstructive pulmonary disease (COPD) and obesity, as well as ß-agonists and antagonists response and toxicity. The purpose of this study was to determine the frequency distribution of ADRB1 genetic variants Ser49Gly and Arg389Gly, ADRB2 variants Gly16Arg and Gln27Glu, ADRB3 variant Trp64Arg in a Southeastern European Caucasian (SEC) population sample and to establish a comparison with existing data from other human populations. A sample of 431 men and 590 women volunteered to participate in this genotyping analysis after anonymization and de-identification. Real Time PCR (Melting Curve Analysis) followed DNA extraction from buccal swabs and statistical analysis of the results was performed. The allele frequencies in the SEC population were Ser49 (90.3%), Arg389 (69.49%), Gly16 (61.61%), Gln27 (65.72%), and Trp64 (94.52%), while a Hardy-Weinberg Equilibrium (HWE) was detected in the population studied. Comparisons for the Ser49Gly, Gln27Glu, and Trp64Arg allele distributions demonstrated significant differences between SEC and the European group. European subgroups comparisons showed that allele distributions were similar for four of the five SNPs between SEC and Southwestern European Caucasians (SWC), while they were quite distinct from the Northwestern European Caucasians (NWC). These data underline the importance of interethnic variability of ß-ARs genetic polymorphisms.
ABSTRACT
BACKGROUND: The emergence of multidrug-resistant nosocomial pathogens, such as Pseudomonas aeruginosa and Acinetobacter baumannii, has led to the revival of the systemic use of antimicrobial agent colistin in critically ill patients, but only limited data are available to define its pharmacokinetic profile in these patients. OBJECTIVE: The aim of this study was to assess steady-state serum concentrations of colistin after i.v. administration of colistin methanesulfonate (CMS) in critically ill patients with stable kidney function. METHODS: This prospective, open-label, uncontrolled study was conducted at 2 intensive care units in the Athens Trauma Hospital, KAT, Athens, Greece. Adult patients were nonconsecutively enrolled if they were critically ill and had stable kidney function (<0.5 mg/dL change in serum creatinine prior to and until the day of sample collection) and had been receiving CMS as part of a treatment regimen for sepsis irrespective of site of infection with multidrug-resistant, gram-negative bacilli. After i.v. administration of 225-mg CMS (with the exception of 1 patient who received 150 mg) every 8 or 12 hours for at least 2 days, blood samples were collected just before and at 10 minutes and 1, 2, 4, 6, and 8 hours after i.v. infusion (duration, 30 minutes) of the colistin dose on the sampling day. RESULTS: Fourteen nonconsecutive patients were enrolled in the study (13 male, 1 female; mean [SD] age, 62.0 [19.2] years; mean [SD] estimated weight, 72.5 [8.5] kg; mean [SD] Acute Physiology And Chronic Health Evaluation II score on admission, 17.1 [6.0]). At steady state, mean (SD) colistin maximum and minimum concentrations were 2.93 (1.24) and 1.03 (0.44) mg/L, respectively, while mean (SD) apparent total body clearance, apparent volume of distribution, and t(1/2) were 13.6 (5.8) L/h, 139.9 (60.3) L, and 7.4 (1.7) hours, respectively. Colistin-related nephrotoxicity was not observed in the study patients. CONCLUSION: CMS dosage regimens administered to these critically ill adult patients were associated with suboptimal Cmax/MIC ratios for many strains of gram-negative bacilli currently reported as sensitive (MIC, < or = 2 microg/mL).
