The contribution of genetic variants of SLC2A1 gene in T2DM and T2DM-nephropathy: association study and meta-analysis.

An association study was conducted to investigate the relation between 14 variants of glucose transporter 1 gene (SLC2A1) and the risk of type 2 diabetes (T2DM) leading to nephropathy. We also performed a meta-analysis of 11 studies investigating association between diabetic nephropathy (DN) and SLC2A1 variants. The cohort included 197 cases (T2DM with nephropathy), 155 diseased controls (T2DM without nephropathy) and 246 healthy controls. The association of variants with disease progression was tested using generalized odds ratio (ORG). The risk of type 2 diabetes leading to nephropathy was estimated by the OR of additive and co-dominant models. The mode of inheritance was assessed using the degree of dominance index (h-index). We synthesized results of 11 studies examining association between 5 SLC2A1 variants and DN. ORG was used to assess the association between variants and DN using random effects models. Significant results were derived for co-dominant model of rs12407920 [OR = 2.01 (1.17-3.45)], rs841847 [OR = 1.73 (1.17-2.56)] and rs841853 [OR = 1.74 (1.18-2.55)] and for additive model of rs3729548 [OR = 0.52 (0.29-0.90)]. The mode of inheritance for rs12407920, rs841847 and rs841853 was 'dominance of each minor allele' and for rs3729548 'non-dominance'. Frequency of one haplotype (C-G-G-A-T-C-C-T-G-T-C-C-A-G) differed significantly between cases and healthy controls [p = .014]. Regarding meta-analysis, rs841853 contributed to an increased risk of DN [(ORG = 1.43 (1.09-1.88); ORG = 1.58 (1.01-2.48)] between diseased controls versus cases and healthy controls versus cases, respectively. Further studies confirm the association of rs12407920, rs841847, rs841853, as well as rs3729548 and the risk of T2DM leading to nephropathy.

Ectoparasite infestations of urban stray dogs in Greece and their zoonotic potential.

The presence of ectoparasites is very common in stray dogs worldwide. So far there are limited data on the spread of external parasites of dogs in Greece. Due to the potential risk of human infestation and/or transmission of zoonotic agents, knowledge of their abundance and distribution is essential in order to better define preventive measures. Therefore, the aim of this study was to assess the prevalence of external parasites of stray dogs from the area of Thessaloniki Greece. Out of a total of 242 stray dogs (85 males and 157 females) tested, the greatest percentages of infestation of 46.28% and 43.8% by fleas (Ctenocephalides felis and Ctenocephalides canis) and ticks (Rhipicephalus sanguineus) respectively were observed. Moreover, 15 dogs (6.20%) were found infested by Sarcoptes scabiei var canis, 8 (3.31%), by Otodectes cynotis while 4 (1.65%) dogs were infested by Cheyletiella sp and Demodex canis. Finally, three dogs (1.24%) were found infested by lice (Trichodectes canis). A statistically significant higher percentage of external parasites was detected in young dogs compared to adults (P=0.0001) and in males compared to females (P<0.0001), while this difference was not statistically significant in short haired compared to long haired and in small size compared to large size dogs (P= 0.6938 and P=0.9934, respectively). The results of this study support the assumption that stray dogs constitute a considerable source of ectoparasites and their infestation is indicative of the presence and abundance of ectoparasites in an area.

Urate crystals induce NLRP3 inflammasome-dependent IL-1ß secretion and proliferation in isolated primary human T-cells.

BACKGROUND: Urate through NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome-dependent caspase-1 activation stimulates macrophages to secrete inteleukin-1ß (IL-1ß). Urate also enhances adaptive immunity indirectly through its effect on antigen presenting cells. In this study, the direct effect of urate on isolated primary human T-cells was evaluated. METHODS: Isolated T-cells were cultured with or without monosodium urate crystals in the presence or not of the NLRP3 inflammasome inhibitor glyburide. Activated cleaved caspase-1 was assessed by means of western blotting, whereas caspase-1 activity was measured colorimetrically in the cell lysates. IL-1ß was measured in the supernatants by means of enzyme-linked immunosorbent assay. T-cell proliferation was assessed by means of bromodeoxyuridine labelling and immunoenzymatic detection. RESULTS: Urate induced caspase-1 activation and IL-1ß release by T-cells. It also induced proliferation of T-cells. Glyburide inhibited urate-induced caspase-1 activation, IL-1ß secretion and proliferation. CONCLUSIONS: Urate, a well defined danger signal, stimulates directly human T-cells in a NLRP3 infmmasomela-dependent way. The subsequent IL-1ß secretion could enhance inflammation, whereas expansion of T-cell clones could facilitate a subsequent adaptive immune response. Hippokratia 2015, 19 (1): 41-46.

Restless legs syndrome does not affect 3-year mortality in hemodialysis patients.

OBJECTIVE: Uremic restless legs syndrome (RLS) has been related to an enhanced mortality of hemodialysis (HD) patients. In the general population studies of this association have yielded inconsistent results. The aim of the present study was to re-evaluate the relationship of RLS and mortality in HD patients. METHODS: We recorded the 3-year mortality in 579 HD patients after assessment for RLS symptoms. This population has been previously evaluated for the prevalence of RLS, according to the essential criteria of the International RLS Study Group. Mortality data were acquired from the national end-stage renal disease registry. Survival probability was calculated by the Kaplan-Meier method and analyzed by the log-rank test. For multivariate survival analysis, we implemented a Cox regression model. RESULTS: During the 3-year follow-up, we documented 118 deaths. Mortality was 15.6% in patients with RLS and 22.3% in patients without RLS (p = 0.079). According to the Cox regression analysis, there was no significant association between RLS and 3-year mortality, either in an age- and gender-adjusted model (hazard ratio [HR] = 0.772, 95% confidence interval [CI] = 0.488-1.219, p = 0.267) or in a multivariate adjusted model (HR = 0.667, 95% CI = 0.417-1.069, p = 0.092). CONCLUSION: Diagnosis of RLS according to the essential criteria of the International RLS Study Group does not seem to influence the 3-year mortality in HD patients. Our findings are in contrast to those in some previous reports, and reinforce the need for further studies of RLS and mortality in HD.

Impact of proton pump inhibitor use on magnesium homoeostasis: a cross-sectional study in a tertiary emergency department.

BACKGROUND: To date, the use of proton pump inhibitors (PPIs) has been associated with a low risk of hypomagnesaemia and associated adverse outcomes. We hypothesised that a better risk estimate could be derived from a large cohort of outpatients admitted to a tertiary emergency department (ED). METHODS: A cross-sectional study was performed in 5118 patients who had measurements of serum magnesium taken on admission to a large tertiary care ED between January 2009 and December 2010. Hypomagnesaemia was defined as a serum magnesium concentration < 0.75 mmol/l. Demographical data, serum electrolyte values, data on medication, comorbidities and outcome with regard to length of hospital stay and mortality were analysed. RESULTS: Serum magnesium was normally distributed where upon 1246 patients (24%) were hypomagnesaemic. These patients had a higher prevalence of out-of-hospital PPI use and diuretic use when compared with patients with magnesium levels > 0.75 mmol/l (both p < 0.0001). In multivariable regression analyses adjusted for PPIs, diuretics, renal function and the Charlson comorbidity index score, the association between use of PPIs and risk for hypomagnesaemia remained significant (OR = 2.1; 95% CI: 1.54-2.85). While mortality was not directly related to low magnesium levels (p = 0.67), the length of hospitalisation was prolonged in these patients even after adjustment for underlying comorbid conditions (p < 0.0001). CONCLUSION: Use of PPIs predisposes patients to hypomagnesaemia and such to prolonged hospitalisation irrespective of the underlying morbidity, posing a critical concern.

Uric acid induces caspase-1 activation, IL-1ß secretion and P2X7 receptor dependent proliferation in primary human lymphocytes.

BACKGROUND: Urate through Nacht Domain, Leucine-Rich Repeat, and pyrin domain-containing protein 3 (NALP3) dependent caspase-1 activation stimulates macrophages to secrete inteleukin-1ß (IL-1ß). Purinergic receptor P2X7 plays a role in the urate induced NALP3 activation. Urate also enhances adaptive immunity indirectly through its effect on antigen presenting cells. In this study, the direct effect of urate on primary human lymphocytes was evaluated. METHODS: Lymphocytes were cultured with or without monosodium urate crystals in the presence or not of a P2X7 inhibitor. Caspase-1 activity was assessed colorimetrically in cell lysates and IL-1ß was measured in supernatants with ELISA. Whole lymphocyte viability and proliferation, as well as T-cell proliferation were assessed by means of 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay and of flow cytometry respectively. RESULTS: Urate induced caspase-1 activation and IL-1ß release by lymphocytes. It also induced proliferation of whole lymphocytes and T-cells as well. P2X7 inhibitor abrogated lymphocyte proliferation. CONCLUSIONS: Urate, a well defined danger signal, stimulates directly human lymphocytes in a P2X7 dependent way. The subsequent IL-1ß secretion could enhance inflammation, whereas expansion of lymphocyte clones could facilitate a subsequent adaptive immune response.

Restless legs syndrome in hemodialysis patients: an epidemiologic survey in Greece.

BACKGROUND: Restless legs syndrome (RLS) is a sensorimotor disorder characterized by an uncontrolled need to move extremities accompanied by unpleasant sensations, which frequently leads to sleep disturbances. In hemodialysis (HD) patients, the previously reported RLS prevalence varied enormously, between 6% and 60%. In our study, we investigated the RLS prevalence in HD patients for the first time in Greece. METHODS: A continuous sample of HD patients was studied between January and September of 2010 in six dialysis units in Greece. RLS diagnosis was based on the essential clinical criteria of the International RLS Study Group (IRLSSG). The standardized incidence ratio (SIR) for RLS in HD patients was calculated in comparison to data from a recent survey of the general population in Greece. RESULTS: In our study of 579 HD patients in Greece (236 women; mean age, 65±13years), the prevalence of RLS was elevated in comparison to the general population (26.6% vs 3.9%), with an SIR of 5.4 (95% confidence interval [CI], 4.6-6.3). In the fully adjusted model, the risk for RLS in HD patients was reduced in older age (odds ratio [OR], 0.98 [95% CI, 0.96-0.99]) and increased in women (OR, 1.60 [95% CI, 1.05-2.43]) in cases with elevated levels of ß2 microglobulin (OR, 1.15 [95% CI, 1.01-1.32]) and intact parathormone (iPTH) (OR, 1.30 [95% CI, 1.08-1.56]). CONCLUSION: A high RLS prevalence was recorded in a large HD population in Greece, clearly suggesting the need for enhanced awareness of RLS in nephrology. The RLS risk was increased in women and in younger HD patients as well as in those with elevated ß2 microglobulin and iPTH levels.

Plasma vascular endothelial growth factor and angiogenin are positively related to erythropoietin dose in hemodialysis patients.

PURPOSE: Experimental data confirmed that erythropoietin (EPO) administration alters the course of various pathological situations such as heart failure and tumor growth by inducing vascular endothelial growth factor-A (VEGF-A) expression. The effect of EPO dose on plasma VEGF-A level in hemodialysis (HD) patients was evaluated. The effect of EPO dose on plasma angiogenin level in HD patients was also evaluated, since angiogenin is necessary for angiogenesis induced by VEGF-A. METHODS: Thirty two HD patients (10 diabetics) enrolled into the study. Patients were iron replete and did not suffer from infections, autoimmune diseases or malignancies. Plasma VEGF-A and angiogenin, as well as serum interleukin-6 and tumor necrosis factor-α were measured by means of ELISA. RESULTS: Weekly EPO dose per kg of dry body weight was positively related to both VEGF-A and angiogenin, whereas no relation was detected among VEGF-A or angiogenin and hemoglobin, inflammation or presence of diabetes mellitus. These relations among EPO dose and VEGF-A or angiogenin remained after adjustment for hemoglobin concentration or inflammation or presence of diabetes mellitus. CONCLUSIONS: EPO dose may affect plasma VEGF-A and angiogenin concentrations in HD patients.

Differential diagnosis of hyperkalemia: an update to a complex problem.

Hyperkalemia is a relative common and sometimes life threatening electorlyte disorder. Although its symptomatic treatment is relatively easy, since precise therapeutic algorithms are available, its differential diagnosis is more complicated. The present review aims to unfold the differential diagnosis of hypekalemia using a pathophysiological, albeit clinically useful, approach. The basic elements of potassium homeostasis are provided, the causes of hyperkalemia are categorized and analysed and finally the required for the diferrential diagnosis laboratory tests are mentioned.

Infections in hemodialysis: a concise review. Part II: blood transmitted viral infections.

Hemodialysis (HD) patients are particularly predisposed to infections. It seems that the HD procedure per se as well as disturbances in both innate and adaptive immunity significantly contribute to this susceptibility. Infections are the major cause of morbidity and the second cause of death following cardiovascular events in HD patients. Episodes of bacteremia and pneumonia account for the majority of severe infections in this population. In addition to these bacterial infections another common problem in HD units is the blood transmitted viral infections, particularly infections caused by hepatitis B virus, hepatitis C virus and Human immunodeficiency virus. A number of safety concerns exist for limiting the spread of these viral infections among HD patients and the staff of the unit. The aim of the present review is to present in a concise albeit practical form the difficult aspect of infections in HD. For practical reasons the review is separated in two parts. The previous first part covered bacteremia and respiratory infections, while the present second part covers blood transmitted viral infections.

Infections in hemodialysis: a concise review - Part 1: bacteremia and respiratory infections.

Hemodialysis (HD) patients are particularly predisposed to infections. It seems that the HD procedure per se as well as disturbances in both innate and adaptive immunity significantly contribute to this susceptibility. Infections are the major cause of morbidity and the second cause of death following cardiovascular events in HD patients. Episodes of bacteremia and pneumonia account for the majority of severe infections in this population. In addition to these bacterial infections another common problem in HD units is the blood transmitted viral infections, particularly infections caused by hepatitis B virus, hepatitis C virus and Human immunodeficiency virus. A number of safety concerns exist for limiting the spread of these viral infections among HD patients and the staff of the unit. The aim of the present review is to present in a concise albeit practical form the difficult aspect of infections in HD. For practical reasons the review is separated in two parts. The present first part covers bacteremia and respiratory infections, while the second part will cover blood transmitted viral infections.

Epigenetic mechanisms and kidney diseases.

In recent years, molecular research has brought to light a series of mechanisms involved in the regulation of gene function without altering the DNA sequence. These mechanisms are described with the term "epigenetics" and include modifications in the structure of the human genome, leading to heritable and potentially reversible changes in gene expression. There is now increasing evidence suggesting that several characteristic features of chronic kidney disease such as hyperhomocysteinemia, subclinical inflammation, increased oxidative stress and others may affect the human epigenome. In addition, animal studies have suggested a possible link between nutrition and environmental exposure during the periconceptional period and epigenetic changes in the expression of major genes implicated in kidney organogenesis; these changes result in a diminished number of nephrons in the developing kidney, which predisposes to an increased risk for hypertension and chronic kidney disease in future life. The understanding of the role of epigenetic phenomena in the pathogenesis of chronic kidney disease opens new avenues for future therapeutic strategies, through the development of pharmaceutical agents that target directly with the changes in the human epigenome. Such epigenetic drugs are already in clinical use for the treatment of cancer as well as under investigation for the use in other diseases. This review will summarize the existing data on the link between epigenetic mechanisms and chronic uremic milieu, as well as the promising results of ongoing research in the field of epigenetic drugs that could represent additional options in our therapeutic armamentarium for patients with chronic kidney disease.

Aeromonas hydrophila as a causative organism in peritoneal dialysis-related peritonitis: case report and review of the literature.

Most episodes of peritoneal dialysis (PD)-related peritonitis could be attributed to a single organism, but in almost 10% of peritonitis episodes multiple organisms are identified. Polymicrobial peritonitis is often related to intra-abdominal pathology, and the prognosis may be poor. Aeromonas spp. have rarely been identified as the causative pathogen in PD-related peritonitis, and a very small number of cases has been reported in the literature. These rod-shaped, gram-negative microorganisms have been isolated from wastewater drainage systems, food, vegetables, and soil. Herein we report a case of polymicrobial peritonitis in a continuous ambulatory peritoneal dialysis (CAPD) patient with systemic lupus erythematosus (SLE), due to a combination of Streptococcus viridans and Aeromonas hydrophila infection. The patient was involved in gardening and was not compliant with her technique protocol. She did not wear a mask and omitted thorough hand washing. The patient was treated with i.p. vancomycin and ceftazidime and peritonitis was resolved. The patient's technique was reassessed, and she was retrained by our PD nurses.

Suppression of humoral immune response to hepatitis B surface antigen vaccine in BALB/c mice by 1-methyl-tryptophan co-administration.

BACKGROUND AND THE PURPOSE OF THE STUDY: Indoleamine 2,3-dioxygenase (IDO) suppresses adaptive immune response. The purpose of this study was to determine the effect of the IDO inhibitor namely 1-methyl-DL-tryptophan (DL-1-MT) on antibody production after vaccination with hepatitis B surface (HBs) antigen. METHODS: Four groups of BALB/c mice were immunized with a HBs antigen vaccine. In the first group the vaccine had no DL-1-MT, whereas in the other three groups the vaccine contained 1 mg, 10 mg and 20 mg DL-1-MT. Blood samples were collected 5 weeks post-vaccination and anti-HBs antibodies in the serum were measured by ELISA. RESULTS: Compared to the three groups of mice that were immunized with the vaccines containing DL-1-MT, serum anti-HBs level was much higher in the mice that were immunized with the vaccine with out DL-1-MT. CONCLUSIONS: Inhibition of IDO at the time of vaccination decreased humoral immune response to HBs antigen vaccine. The idea that IDO activity is simply immunosuppressive may need to be re-evaluated.

Lipopolysaccharide and hypoxia significantly alters interleukin-8 and macrophage chemoattractant protein-1 production by human fibroblasts but not fibrosis related factors.

Besides extracellular matrix production, fibroblasts are able to produce various cytokines. Their ubiquitous position makes fibroblasts appropriate cells for sensing various noxious stimuli and for attracting immune cells in the affected area. In the present study the effect of lipopolysaccharide (LPS) and cobalt chloride (CoCl(2)) on the above fibroblasts functions were evaluated in primary human skin fibroblasts cultures. Collagen, matrix metalloproteinase-1, tissue inhibitor of metalloproteinases-1, transforming growth factor-ß1, interleukin-8 (IL-8) and macrophage chemoattractant protein-1 (MCP-1) were measured in fibroblasts culture supernatants. Fibroblasts proliferation and viability were assessed as well. Hypoxia inducible factor-1α and the phosphorylated p65 portion of NF-κB were assessed in fibroblasts protein extracts. LPS and CoCl(2) had a minor effect on fibrosis related factors in human primary fibroblasts, possibly due to the absence of interplay with other cell types in the used experimental system. On the contrary both LPS and CoCl(2) increased significantly IL-8. LPS also increased considerably MCP-1, but CoCl(2) decreased it. Thus LPS and CoCl(2) induce a sentinel, nevertheless not identical, phenotype in primary human fibroblasts. The last disparity could result in different body response to infectious or hypoxic noxious stimuli.

Acute renal failure after antibiotic-impregnated bone cement treatment of an infected total knee arthroplasty.

Antibiotic-impregnated cement is used frequently in revision procedures of infected total hip and knee arthroplasties. Local antibiotic treatment is as effective as the use of systemic antibiotics. The purpose of such treatment is to provide high tissue concentrations of antibiotics and minimize systemic toxicity, especially nephrotoxicity. Though antibiotic-impregnated cement is considered safe in terms of nephrotoxicity, two cases that have implicated aminoglycoside-impregnated cement in acute renal failure (ARF) after surgery for an infected total knee arthroplasty (TKA) have been reported [Curtis et al. 2005, Van Raaij et al. 2002]. Two more cases of postoperative ARF after use of combined tobramycin- plus vancomycin-impregnated cement, this time in total hip arthroplasty, have been recently reported [Patrick et al. 2006]. We report a case of ARF in a 61-year-old patient with a history of diabetes mellitus and hypertension after treatment of a febrile infection of a TKA with combined gentamicin- plus vancomycin-impregnated cement. The ARF could not sufficiently be attributed to other causes and though serum concentrations of antibiotics obtained from the 8th postoperative day and thereafter were far below the trough levels associated with nephrotoxicity, gentamicin and vancomycin seem to have contributed significantly to ARF in our case.

L-arginine supplementation does not affect chemically induced carcinogenesis and tumor growth in BALB-c mice.

UNLABELLED: T-cell zeta-chain downregulation is common in various types of cancer and it is proposed as a mechanism of cancer immunosubversion. L-arginine consumption by arginase rich suppressor myeloid cells has been incriminated. The effect of L-arginine supplementation on chemically induced carcinogenesis and tumor growth in mice was evaluated. METHODS: Eight-week old female BALB-c mice were used. Ten mice were injected i.m. with 0.6 mg methylcholanthrene (MCA) once. Ten mice were injected with MCA once and were receiving L-arginine supplementation (5% in animal drinking water) continuously during the study. Mice with cancer were sacrificed 12 weeks after. RESULTS: From the 10 MCA injected mice 6 developed sarcoma. From the 10 MCA injected mice that were receiving L-arginine supplementation 7 developed sarcoma. L-arginine supplementation did not affect MCA induced carcinogenesis (p=1.0, Fisher's exact test). The weight of tumors was not different between the tumors derived from mice that were or were not receiving L-arginine supplementation (1088.3+/-590.2 mg vs. 969.6+/-608.1 mg respectively, p=0.729, unpaired t-test). CONCLUSION: L-arginine supplementation does not affect chemically induced carcinogenesis and tumor growth in BALB-c mice. Although zeta-chain downregulation could be a mechanism of cancer immunosubversion there are enough other cancer immunosubversion mechanisms that were not overwhelmed by L-arginine supplementation. Additionally, except cancer immunosubversion, cancer immunoselection is another, possibly more significant, mechanism of tumor escape from immunosurveillance.

Expression of transforming growth factor-beta receptor II mRNA in cyclosporine-induced gingival overgrowth.

Gingival overgrowth (GO), characterized by increased cellular and extracellular matrix components in gingival tissue, is a frequent side effect of cyclosporine (CsA). In previous studies, elevated levels of transforming growth factor-beta (TGF-beta) have been detected in GO tissue, which led to the conclusion that TGF-beta plays a major part in the pathogenesis. TGF-beta activity is mediated by three receptors; TGF-beta receptor II (TGF-beta RII), the most important, has been immunohistochemically detected in GO and normal gingival tissue. The aim of this study was to clarify whether TGF-beta RII is overexpressed in CsA-induced GO. The expression of TGF-beta RII mRNA in GO tissue of patients on CsA (n = 10, 5 women, aged 42.5 +/- 14.9 years) with renal transplantation (transplant duration 3.6 +/- 0.96 years) was compared with that in healthy gingiva of control subjects (n = 10, 5 women, aged 42.5 +/- 7.6 years). Semiquantitative reverse transcribed-polymerase chain reactions (RT-PCR) were applied with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an internal standard. TGF-beta RII mRNA was readily detected in the GO tissue of patients on CsA. The level of TGF-beta RII mRNA relative to GAPDH in GO cases was not significantly higher than the relative TGF-beta mRNA level in normal gingiva (0.60 +/- 0.16 vs 0.52 +/- 0.19; P = .575). The precise mechanism of CsA-induced GO remains uncertain. According to our results, TGF-beta RII was not upregulated in CsA-induced GO, and may have no important role in this disorder. However, the involvement of TGF-beta in the molecular pathology of GO may be mediated via TGF-beta RI or RIII.