Comparison of the behavior of negative electrically charged E. coli and E. faecalis bacteria under electric field effect.

The negative electrical charge of Escherichia coli and Enterococcus faecalis bacteria is an indication that they can be affected by an electric field. To show that the movements of electrically charged bacteria can be controlled, impedance spectroscopy method was used on a porous silicon (PS) structure with 60 % porosity and 7-12 µm pore size. The main purpose of this study is to use the electric charge of these two bacterial species to bring bacteria closer to the sensors with the help of an electric field, and to compare the behavior of these bacterial species in the process. The effect of bacterial contact on porous silicon surface impedance spectra was studied under electrical fields between 0 and 5 kV/cm at a constant bacterial concentration. It was observed that both bacteria can be approximated to the PS surface by the electric field effect. However, the shape and dimensional differences of these two bacterial species caused differences both in their movements in the electric field and in their settlement on the PS surface, and these differences were interpreted. In addition, similar experiments were repeated for dead bacteria and it was determined that the electric field control was not the same as for living bacteria.

What plays a role in the severity of atopic dermatitis in children?

Background/aim: Determining the characteristics and risk factors of severe disease is extremely important to combat atopic dermatitis (AD), which has recently shown increasing prevalence. In this study, we aimed to investigate the clinical characteristics of pediatric patients with AD and identifying the factors associated with the severity of the disease. Materials and methods: A total of 304 pediatric patients diagnosed with atopic dermatitis were included in the study. The patients' age at admission, age at onset of symptoms, the presence of atopy history in their family, eosinophil levels obtained from blood counts were recorded, together with the data of cigarette exposure, and area of residence. Disease severity was determined according to the SCORAD index. Epidermal prick tests (EPT) were applied to all patients. Results: There was a negative correlation between the SCORAD score and both age at admission (r = 0.277, p < 0.001) and age at onset of the symptoms (r = ­0.474, p < 0.001). Food sensitization rates were higher in individuals with moderate-severe disease (90.7% vs. 23.1%; p < 0.001) and patients with food allergy (FA) had significantly higher SCORAD scores [33 (IQR: 22­44) vs. 14 (IQR: 12­16); p < 0.001]. SCORAD scores of the individuals living in rural areas were higher than the ones living in urban [22 (IQR: 15­39.5) vs. 15 (IQR: 12­22); p < 0.001]. Familial atopy history was more common in patients with moderate-severe disease (66.5% vs. 17.5%; p < 0.001). The SCORAD scores were higher in patients exposed to passive smoking [21 (IQR:14.75­38) vs. 13 (IQR: 12­16); p < 0.001]. The eosinophil count found to be positively correlated with SCORAD scores (r = 0.531, p < 0.001). Conclusion: Our findings show that early-onset, food sensitivity, living in rural areas, having familial atopy history and passive cigarette smoke exposure play a role in severe AD. Since it is remarkably correlated with SCORAD scores, eosinophil count can be used as a marker to assess the severity of AD in children.

Evaluation of clinical, neuroradiologic, and genotypic features of patients with L-2-hydroxyglutaric aciduria.

AIM: L-2-hydroxyglutaric aciduria is a slowly progressive neurometabolic disorder caused by an enzymatic deficiency of L-2-hydroxyglutarate dehydrogenase. Here, we aimed to evaluate the clinical, neuroradiologic, and genotypic characteristics of patients with L-2-hydroxyglutaric aciduria who were followed in our outpatient clinic. MATERIAL AND METHODS: Twenty-five patients with L-2-hydroxyglutaric aciduria were enrolled in the study. Data regarding demographic, clinical, and neuroradiologic findings and molecular analysis were evaluated retrospectively. RESULTS: The mean age of patients at the time of diagnosis was 12.09±8.02 years, whereas the mean age at the time of the first symptoms was 39.47±29.96 months. Diagnostic delay was found as 9.95±7.78 years. Developmental delay, decrease in school success, and seizures were the most common initial symptoms; however, behavioral problems and seizures became more prominent in the disease course. At the time of diagnosis, mental retardation and at least one pathologic cerebellar finding were detected in all symptomatic patients. Three patients developed brain tumors. The most common neuroimaging findings were subcortical white matter changes and cerebellar dentate nucleus involvement. In one patient, there was only isolated basal ganglia involvement without white matter lesions. Patients with similar genotypic features exhibited different clinical and radiologic findings. CONCLUSION: Although clinical symptoms appear early in L-2-hydroxyglutaric aciduria, there is approximately a ten-year delay in diagnosis. In subjects in whom brain tumor is detected in early childhood, L-2-hydroxyglutaric aciduria should be considered in the differential diagnosis in the presence of mental retardation accompanied by developmental delay, cerebellar and pyramidal findings, and behavior disorders in a wide spectrum ranging from autism spectrum disorder to psychosis. In patients with L-2-hydroxyglutaric aciduria, incipient headache, tinnitus, altered consciousness, and seizures can be indicative of brain tumors.

Anemia after kidney transplantation: Does its basis differ from anemia in chronic kidney disease?

BACKGROUND: Although similar factors play a role in both PTA and anemia in patients with CKD, additional risk factors exist in the pathogenesis of PTA. The present study aimed at comparing anemia and inflammation-related parameters between RTx recipients and CKD patients and elucidating the risk factors of PTA. METHODS: This single-centered, cross-sectional study consisted of 68 participants: 48 were in the RTx group and 20 were in the CKD group. The CKD patients were comparable to the RTx recipients in terms of age, gender, and eGFR. Serum levels of EPO, hepcidin, and IL-6 were measured by enzyme-linked immunosorbent assays. The ratio of EPO/Hb was calculated to estimate endogenous EPO resistance. RESULTS: The prevalence of anemia was 46% in the RTx group and 30% in the CKD group (P = .23). RTx recipients had significantly lower Hb (P = .04), higher EPO (P < .001), and ferritin levels (P = .001), and higher EPO/Hb ratios (P < .001); however, CKD patients showed a higher frequency of absolute iron deficiency (P = .008). Neither hepcidin nor IL-6 levels differed between the two groups. Hb level of RTx recipients was correlated with only eGFR (r = .437, P = .002) but not with any of the transplantation-related factors, while Fe level was the only parameter to be correlated with Hb level of CKD patients (r = .622, P = .01). CONCLUSION: In the present study comparing GFR-matched RTx and CKD patients, lower GFR level appears to be the factor most strongly associated with anemia, and endogenous EPO resistance is among the contributing factors to PTA.

Electric field assisted deposition of E. coli bacteria into the pores of porous silicon.

The effect of the electric field strength on the Escherichia coli (E. coli) bacteria deposition into the pores of porous silicon was investigated by impedance spectroscopy technique. The main idea behind this approach is that negatively charged E. coli bacteria can be deposited into the pores available on the surface of porous silicon upon the application of a high electric field. For this purpose, the influence of the E. coli concentration on the impedance spectra of the anodically formed porous silicon under various electric fields between 0 and 10 kV/cm was investigated. In addition, the effect of the application time of a constant electric field of 12 kV/cm on the impedance spectra of porous silicon exposed to living and dead bacterial cells was also investigated. The results reported in this study indicate that the number of live E. coli bacteria deposited into the pores of porous silicon can be controlled by the applied electric field strength. On the other hand, it was found that there is no considerable effect of the dead E. coli cell concentration on the recorded impedance spectra of the porous silicon based sensor platform.

Oxidative stress among L-2-hydroxyglutaric aciduria disease patients: evaluation of dynamic thiol/disulfide homeostasis.

L-2-hydroxyglutaric aciduria (L2HGA) is an autosomal recessive disorder that is caused by deficiency of 2-hydroxyglutarate dehydrogenase. Pathophysiology of brain damage is poorly understood. In recent years, it was proposed that oxidative stress was elevated and led to brain injury. Aim of this study is to evaluate thiol/disulphide homeostasis as an indicator of oxidative stress in L2HGA patients who have been receiving antioxidant treatment. Sixteen L2HGA patients and 16 healthy individuals were included in the study. All the L2HGA patients were regularly followed up and presented neurological dysfunction at different grades. Fourteen patients had been receiving antioxidant treatment. Serum native thiol (-SH), total thiol (-SH + -S-S-) and disulphide (-S-S) levels were measured. Disulphide/native thiol, disulphide/total thiol and native thiol/total thiol ratios were calculated from these values. No significant difference was observed in -SH, -SH + -S-S-, -S-S levels between two groups. In addition to that, no increase of disulphide/native thiol and disulphide/total thiol ratios was detected. Thiol/disulphide homeostasis parameters were also compared between patients who had been receiving and not receiving antioxidant therapy; and between different types of antioxidant therapy and the results did not point to any significant difference. This is the first study that evaluates dynamic thiol/disulphide homeostasis as an indicator of oxidative stress in L2HGA and it has one of the largest sample sizes among previous studies. In our study we suggest that antioxidant therapy should be effective in preventing oxidative stress in L2HGA patients, which has been reported in previous studies and should be a part of standard therapy.

Leptin and ghrelin in chronic kidney disease: their associations with protein-energy wasting.

BACKGROUND: This study aimed to evaluate plasma concentrations of leptin and total ghrelin in children with chronic kidney disease (CKD) and assess their roles in protein-energy wasting (PEW). METHODS: This study consisted of three different CKD populations [CKD group (20 patients with non-dialysis CKD), dialysis group (39 patients on dialysis), and kidney transplant (KTx) group (35 KTx recipients)] and control group (18 healthy children). Plasma leptin and total ghrelin levels were measured. Multi-frequency bioimpedance analysis was used for the assessment of fat and lean mass. PEW was defined using criteria including body mass, muscle mass, growth, serum albumin level, and protein intake. RESULTS: While plasma leptin levels did not differ among the study groups, total ghrelin levels were significantly higher in the dialysis group (P < 0.001). Seven dialysis patients (18%) and one CKD patient (5%) but none of the KTx recipients met the criteria of PEW. Dialysis patients with PEW had lower plasma leptin levels compared to their counterparts (P = 0.018); however, total ghrelin levels did not differ between the two groups (P = 0.10). Low leptin level in dialysis patients was independently associated with lower fat mass index (P < 0.001) and lower height-specific SD scores of BMI (P = 0.019). CONCLUSIONS: PEW is prevalent in dialysis patients. Low levels of leptin seem to be associated with PEW. Our result suggests that low leptin levels may be a consequence rather than a cause of PEW. Longitudinal studies are required to investigate this complex relationship between leptin and PEW in pediatric dialysis patients.

A Case of Vitamin D-Dependent Rickets Type 1A with a Novel Mutation in the Uzbek Population.

Vitamin D-dependent rickets type 1A (VDDR-1A) (Online Mendelian Inheritance in Man #264700) is a rare, autosomal recessively inherited disorder due to inactivating mutations in CYP27B1. It is characterized by early onset of rickets with hypocalcemia. We aimed to describe the clinical and laboratory findings in a VDDR-1A case and to report a novel homozygote truncating mutation NM_000785.3 c.403C>T (p.Q135*) in CYP27B1 which to our knowledge is the first described mutation in the Uzbek population. The patient was admitted with tetany at the age of 12 months. He was a healthy Uzbek boy until 9 months of age when he had a seizure due to hypocalcemia. Vitamin D treatment was given orally in Turkmenistan (no data available for dose and duration). The patient was the product of a consanguineous marriage. His brother had died with hypocalcemia and pneumonia. At physical examination, anthropometric measurements were within normal limits; he had caput quadratum, enlarged wrists, and carpopedal spasm. Blood calcium, phosphorus, alkaline phosphatase, and parathormone (PTH) levels were 5.9 mg/dL, 3.5 mg/dL, 987 IU/L, and 182.8 pg/mL (12-72), respectively. Radiological findings included cupping and fraying of the radial and ulnar metaphyses. Renal ultrasound revealed nephrocalcinosis (grade 1). Despite high serum PTH and 25-hydroxyvitamin D3 levels, 1,25-dihydroxyvitamin D3 level was low, suggesting a diagnosis of VDDR-1A. The patient was treated with calcium carbonate and calcitriol. DNA sequencing revealed a novel homozygous mutation of NM_000785.3 c.403C>T (p.Q135*) in CYP27B1. VDDR-1A is a rare disorder which needs to be considered even in countries where nutritional vitamin D deficiency is still common.