Vassilios Vargemezis

The serotonin transporter promoter polymorphism (5-HTTLPR) is associated with type 2 diabetes.

BACKGROUND The serotonergic system contributes substantially to the regulation of glucose homeostasis and feeding. 5-HTTLPR is a serotonin transporter (5-HTT) gene-linked polymorphic region that regulates the transcriptional activity of 5-HTT. Our aim was to investigate the possible association of 5-HTTLPR polymorphism with type 2 diabetes mellitus and obesity. METHODS Study population consisted of 252 subjects diagnosed with Type 2 DM and 211 non-diabetic subjects, all Caucasians of Greek ethnic origin. Genomic DNA was extracted from peripheral blood and analyzed for 5-HTTLPR polymorphism with a novel PCR protocol. RESULTS The frequency of SS and SL genotypes of HTTLPR was significantly higher in the diabetic group (77.0%) than in the non-diabetic group (61.6%) (P<0.001). The genetic risk of Type 2 DM for subjects carrying at least one S allele was increased compared to non-diabetic subjects (OR=2.08, 95% CI=1.39-3.12). When subjects were divided according to BMI status, the frequency of S allele carriers was similar in obese and non-obese subjects. CONCLUSIONS The S allele of 5-HTTLPR is strongly associated with the presence of Type 2 DM. This association appears to be direct and not dependent on obesity status. Therefore, 5-HTTLPR LL genotype might be protective for development of Type 2 DM.

Can dialysis modality influence quality of life in chronic hemodialysis patients? Low-flux hemodialysis versus high-flux hemodiafiltration: a cross-over study.

Background: Hemodiafiltration with online preparation of the substitution [online high-flux hemodiafiltration (OHDF)] and hemodiafiltration with prepared bags of substitution (HDF) are important, recently widely used renal replacement therapies in patients with end-stage renal disease. However, there is little information on the comparative impacts of these modalities versus conventional low-flux hemodialysis (HD) on the quality of life (QoL) of HD patients. This study investigates the effect of dialysis modality on QoL in chronic HD patients. Methods: In this prospective, randomized, cross-over, open label study, 24 patients were enrolled. Their age were 62 ± 13.34 years (mean ± SD), with the duration of dialysis of 31 ± 23.28 months (mean ± SD). Five of the patients were women. QoL was measured by the Short-Form Health Survey with 36 questions (SF-36) and subscale scores were calculated. Each patient received HD, OHDF, and HDF for 3 months, with the dialysis modality subsequently being altered. They completed the questionnaire of QoL at the end of each period. Results: There were statistical significant differences in QoL for the total SF-36 [36.1 (26.7–45.7) and 40.7 (30.2–62.8)], for classic low-flux HD and high-flux hemodiafiltration, for bodily pain [45 (26.9–66.9) and 55 (35.6–87.5)], and for role limitations due to emotional functioning [0 (0–33.3) and 33.3 (0–100)], respectively. The scores did not differ significantly between the two types of hemodiafiltration. Conclusions: Our study indicates that QoL differs significantly among patients receiving low-flux HD and high-flux hemodiafiltration, on total SF-36, bodily pain, and role limitations due to emotional functioning. Convective modalities may offer better QoL than diffusive HD.

Combined pulmonary fibrosis and emphysema associated with microscopic polyangiitis

To the Editors: Microscopic polyangiitis (MPA) is a necrotising multiorgan vasculitis associated with a variety of circulating autoantibodies, such as anti-neutrophil cytoplasm antibodies (ANCAs) against myeloperoxidase (MPO) [1]. Typical and most common pulmonary involvement comprises of alveolar haemorrhage secondary to pulmonary capillaritis as well as interstitial lung fibrosis [2] and progressive obstructive lung disease [1, 3, 4]. The combination of pulmonary fibrosis and emphysema (CPFE) is a recently defined syndrome, encompassing a distinct radiology, revealing both upper-lobe emphysema and lower-lobe fibrosis on high-resolution computed tomography (HRCT) of the chest, as well as lung function profile, with apparently preserved lung volumes contrasting with disproportionally impaired gas exchange, as assessed by reduced diffusing capacity of the lung for carbon monoxide [5, 6]. CPFE has been recently described in the context of connective tissue diseases [7]. Nevertheless, it is still debatable whether CPFE represents a distinct syndrome or it is just a phenotype of pulmonary fibrosis with coincidental emphysema. Here, we describe for the first time, in a male patient, a novel type of pulmonary manifestation of MPA, the combination of pulmonary fibrosis and emphysema. In 2008, an 80-yr-old Greek-Caucasian male, heavy ex-smoker (80 pack-yrs), ex-farmer and coal worker with a history of idiopathic pulmonary fibrosis, based …

The -759C/T polymorphism of the 5-HT2C receptor is associated with type 2 diabetes in male and female Caucasians.

Objectives Type 2 diabetes mellitus and obesity constitute serious health problems. Studies reveal that the 5-HT2C receptor contributes substantially to the regulation of a wide variety of behavioral and physiological processes including feeding and glucose homeostasis. Our aim was to determine the possible association of the -759C/T polymorphism of the 5-HT2C receptor gene with type 2 diabetes and obesity in male and female individuals Caucasian origin. Methods The study population consisted of 151 patients diagnosed with type 2 diabetes and 164 nondiabetic patients, all of Greek origin. Genomic DNA was extracted from peripheral blood and analyzed for the -759C/T polymorphism of the 5-HT2C receptor gene using polymerase chain reaction-restriction fragment length polymorphism method. Results The frequency of T allele of the -759C/T polymorphism of the 5-HT2C receptor was significantly lower in the diabetic group (12.6%) than in the nondiabetic group (23.3%) (P=0.003). The genetic risk of type 2 diabetes for patients not carrying the T allele was increased compared with nondiabetic patients (odds ratio (OR)=2.34, 95% confidence interval (CI)=1.36–4.02). The reduced frequency of T allele was present both in male [10% in patients with diabetes and 21.6% in patients without diabetes (P=0.041)] and female patients [14.1% in patients with diabetes and 24.3% in patients without diabetes (P=0.030)]. In contrast, the frequency of T allele was similar in obese (16.4%) and nonobese (17.1%) patients. Conclusions Lower frequency of -759T allele of the 5- HT2C receptor gene was associated with type 2 diabetes but not with obesity in male and female Caucasians. Thus, this polymorphism might constitute a prognostic marker for diabetic risk.

Calcific Uremic Arteriolopathy Treated with Cinacalcet, Paricalcitol, and Autologous Growth Factors

Background: Calcific uremic arteriolopathy is an uncommon cutaneous ischemic necrotizing disease, most commonly associated with renal disease and hyperparathyroidism, bearing a high mortality rate. Objective and Method: A case of a 57-year-old female renal patient with hyperparathyroidism who was successfully treated with combined paricalcitol and cinacalcet systemically, while autologous growth factors were locally applied, is herein presented. Result and Conclusion: The combination of cinacalcet and paricalcitol is a reliable alternative to parathyroidectomy in patients with calcific uremic arteriolopathy and hyperparathyroidism. Meticulous débridement of necrotic tissues is essential and application of autologous growth factors promotes healing.

Exploring Genomic Structure Differences and Similarities between the Greek and European HapMap Populations: Implications for Association Studies

Studies of the genomic structure of the Greek population and Southeastern Europe are limited, despite the central position of the area as a gateway for human migrations into Europe. HapMap has provided a unique tool for the analysis of human genetic variation. Europe is represented by the CEU (Northwestern Europe) and the TSI populations (Tuscan Italians from Southern Europe), which serve as reference for the design of genetic association studies. Furthermore, genetic association findings are often transferred to unstudied populations. Although initial studies support the fact that the CEU can, in general, be used as reference for the selection of tagging SNPs in European populations, this has not been extensively studied across Europe. We set out to explore the genomic structure of the Greek population (56 individuals) and compare it to the HapMap TSI and CEU populations. We studied 1112 SNPs (27 regions, 13 chromosomes). Although the HapMap European populations are, in general, a good reference for the Greek population, regions of population differentiation do exist and results should not be light‐heartedly generalized. We conclude that, perhaps due to the individual evolutionary history of each genomic region, geographic proximity is not always a perfect guide for selecting a reference population for an unstudied population.

Rigorous Vibrio vulnificus Soft Tissue Infection of the Lower Leg in a Renal Transplant Patient Managed by Vacuum Therapy and Autologous Growth Factors

Background: Vibrio vulnificus is a gram-negative marine bacterium that grows well in coastal waters. It is an opportunistic pathogen that can cause serious life-threatening infections in patients with certain health conditions. Vibrio-induced wound infections in immunosuppressed patients are difficult to treat because the healing process may be significantly delayed. Reconstructive surgery may not be successful in early treatment as skin grafts are likely to fail, and there may be increased morbidity of donor sites of grafts or flaps. Objective: Herein a case of septicemia and wound necrosis owing to V. vulnificus wound infection in a renal transplant patient is reported. Method: To conservatively yet adequately débride the wound bed, stimulate angiogenesis, and accelerate granulation, vacuum-assisted closure was employed. Granulation was further enhanced by autologous platelet concentrate spray, which has also been reported to increase the epithelialization rate. Result: Complete epithelialization of the wound was achieved 4 weeks after completion of treatment. Conclusion: Noninvasive advanced modalities may be employed to successfully treat infectious soft tissue deficits in immunocompromised patients.

Effects of Parenteral Infusion of Amino Acid Solutions in Acid-BaseBalance in Patients with Advanced Chronic Renal Failure

Malnutrition is a very common condition in patients with chronic kidney disease (CKD), especially after the 3rd stage (GFR 30-59 mL/min/1.73 m2). It affects virtually every organ and the function of the entire organism as well and therefore influences the survival. Moreover, the supplementation of amino acids could correct the negative nitrogen balance of those patients improving their survival rates, while little is known regarding any possible negative effect of this supplementation of amino acids on the acid-base balance. We investigated the impact of parenteral infusion of two different kinds of amino acid solutions (specific for CKD patients and nonspecific) in 25 patients (12F, 13M), suffered from chronic renal failure in stages 3 and 4 (GFR 16 to 45.1 mL/min/1.73 m2). The specific for uremic CKD patients solution A was administrated for 5 days, and after an interval of one week, we treated the same patients for another 5 days with the second non-specific solution B, with usual composition), in order to investigate their influence on patients’ acid-base balance. Comparing the results of the first and the last infusion of solution A, neither pH nor blood gases analysis presented significant differences, while solution B induced statistically significant changes in both pH and blood gases, (p=0.0001). Acidosis was resulted in by the reduction of serum levels of HCO3 - whereas not any significant change observed in serum lactate levels after the infusion of each solution. These results suggest that for patients with chronic kidney disease in stages 3 and 4 who require the administration of a supplementary amino acid solution, the CKD-specific solution A may be preferred, since it prevents the worsen of the metabolic acidosis, which is commonly present in these patients.