Structure and selected properties of Al-Cr-Fe alloys with the presence of structurally complex alloy phases.

The aim of the study was to supplement the data on the Al65Cr20Fe15 alloy with binary phase structure and the Al71Cr24Fe5 alloy with multiphase structure prepared with two different cooling rates from the liquid state. The presence of the structurally complex Al65Cr27Fe8 phase was confirmed by neutron diffraction, scanning electron microscopy with the analysis of chemical composition and transmission electron microscopy. Additionally, the Al8Cr5 phase with γ-brass structure was identified for Al71Cr24Fe5 alloy in both cooling rates from the liquid state. Due to the interesting features of structurally complex alloys, the wear resistance, magnetic properties, and corrosion products after performing electrochemical tests were examined. Based on pin-on-disc measurements, a lower friction coefficient was observed for the Al65Cr20Fe15 alloy (µ ≈ 0.55) compared to the Al71Cr24Fe5 multiphase alloy (µ ≈ 0.6). The average hardness of the binary phase Al65Cr20Fe5 alloy (HV0.1 = 917 ± 30) was higher compared to the multiphase Al71Cr24Fe5 alloy (HV0.1 = 728 ± 34) and the single phase Al-Cr-Fe alloys described in the literature. Moreover, the beneficial effect of rapid solidification on hardness was demonstrated. The alloys Al65Cr20Fe15 and Al71Cr24Fe5 showed paramagnetic behavior, however rapidly solidified Al71Cr24Fe5 alloy indicated an increase of magnetic properties. The studied alloys were characterized by the presence of passive layers after electrochemical tests. A higher amount of oxides on the surface of the Al71Cr24Fe5 alloy was recorded due to the positive effect of chromium on the stabilization of the passive layer.

Introducing a class of standardized and interchangeable parts utilizing programmed ribosomal frameshifts for synthetic biology applications.

Synthetic biology and the rational design of biological devices depend on the availability of standardized and interchangeable biological parts with diverse range of functions. Reliable access to different reading frames during translation has largely been overlooked as functionality for bioengineering applications. Here we report the construction and initial characterization of the first member of such a class of biological parts that conforms to the BioBrick Standard (RFC25), allowing its interchangeable use in biological devices. Using our standardized frameshifting signal consisting of a UUUAAAG slippery sequence, a 6 nt spacer and an engineered pseudoknot based on the infectious bronchitis virus pseudoknot PK401 embedded in a dual reporter construct, we confirm that the frameshifting activity is comparable to the previously published frequency despite the introduced sequence changes. The frameshifting activity is demonstrated using SDS-PAGE and fluorescence spectroscopy. Standardized programmable ribosomal frameshift parts with specific frameshifting frequencies will be of utility for applications such as double coding DNA sequences by expanding the codable space into the -1 frame. Programmed shifting into the -1 frame to bypass a stop codon allows labeling of a protein pool with a fixed stoichiometry of fusion protein, as well as the construction of multi-enzyme expression constructs with specific expression ratios. A detailed understanding of the structural basis of programmed frameshifting will provide the opportunities to rationally design frameshifting elements with a wide range of applications in synthetic biology, including signals that are regulated by small ligands.

[Obesity and diabetes mellitus].

New literature data and the results of own researches concerning the role of excessive body weight and the development of type 2 diabetes mellitus in humans are presented in the analytical review. Inaccordance with current insights, obesity and type 2 diabetes are considered diseases of inflammatory nature, characterized by systemic chronic low-grade inflammation, where different kinds of cytokines are cardinally involved. Unfavourable life style, i.e. excessive, high-energy, and irrational nutrition--an excessive consumption of animal fats and foods containing the high amount of glucose and starch with an insufficient use of high fiber vegetables, fish and vitamin D, and also sedentary, inactive life style leads to adipocyte hypertrophy and migration of M1 macrophages into the adipose tissue (AT). As a result, there is a low-grade inflammation accompanied by an increased production of proinflammatory cytokines (IL-1, IL-6, TNF-α, etc.), adipokines (leptin, resistin, visfatin etc.) and chemokines (CCL2, CCL5, CCL26 and CX3C). Under the influence of these cytokines, on the one hand, IR "is emerged", and on the other--there is apoptosis of the ß-cells, that should be followed by the occurrence of clinically diagnosed type 2 diabetes. However, there is also the opposite system in humans, protecting the organism from the development of type 2 diabetes, and including an increase in the formation of M2 macrophages and the increased formation of secretion of antidiabetic cytokines (IL-4, IL-10, IL-13, etc.) and adiponectin.

Glycated albumin, not hemoglobin A1c, predicts cardiovascular hospitalization and length of stay in diabetic patients on dialysis.

BACKGROUND: The utility of glycated hemoglobin (HbA1c) and glycated albumin (GA) in diabetic dialysis patients remains unknown. GA was previously associated with all-cause hospitalization and patient survival. Relationships between GA, HbA1c, and casual plasma glucose (PG) with cause-specific cardiovascular (CV) disease, infectious disease (ID), and vascular access- (VA) related hospitalization rates and length of stay (LOS) were assessed. METHODS: 444 prevalent diabetic dialysis patients had monthly PG, quarterly GA, and all HbA1c values recorded for 2.33 years; hospitalizations within 17 and 30 days of testing were evaluated. Best-fit, time-dependent Cox models were constructed in unadjusted, case-mix-adjusted (age, sex, race, BMI, diabetes duration, dialysis vintage), and case-mix- plus lab-adjusted (hemoglobin, albumin, phosphorus) models. RESULTS: Mean ± SD diabetes duration was 18.5 ± 10.8 years and dialysis vintage 2.9 ± 2.6 years. In fully adjusted models, CV hospitalization rates were associated with increasing GA (HR 1.32; 95% CI 1.11-1.57; p = 0.002 at 17 days; HR 1.21; p = 0.02 at 30 days) and PG (HR 1.10; 95% CI 1.02-1.17; p = 0.01 at 17 days; HR 1.07; p = 0.03 at 30 days), not HbA1c (HR 1.24; 95% CI 0.89-1.73; p = 0.21 at 17 days; HR 1.26; p = 0.10 at 30 days). LOS for CV admissions was positively associated with GA (HR 1.18; 95% CI 1.01-1.39; p = 0.03), not PG (HR 1.04; 95% CI 0.99-1.10; p = 0.15) or HbA1c (HR 1.03; 95% CI 0.92-1.15; p = 0.21). Admissions due to ID and VA complications (and LOS) did not correlate with these assays. CONCLUSIONS: Improved glycemic control based on GA and PG predicted CV-related hospitalizations; GA also predicted CV hospitalization LOS. HbA1c did not predict cause-specific hospitalizations in dialysis populations.

Glycated albumin and risk of death and hospitalizations in diabetic dialysis patients.

BACKGROUND AND OBJECTIVES: Relative to hemoglobin (Hb) A(1c), glycated albumin (GA) more accurately reflects glycemic control in patients with diabetes mellitus and ESRD. We determined the association between GA, HbA(1c), and glucose levels with survival and hospitalizations in diabetic dialysis patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Quarterly GA levels were measured for up to 2.33 years in 444 prevalent patients with diabetes and ESRD. Proportional hazard time-dependent covariate models were computed with adjustment for demographic characteristics, comorbidities, and laboratory variables. Similar analyses were performed for available HbA(1c) and monthly random serum glucose determinations. RESULTS: The participants were 53% male, 54% African American, 43% Caucasian, 90% on hemodialysis, with a mean (SD) age of 62 (12) years and median follow-up duration of 2.25 years. GA and HbA(1c) mean ± SD 21.5% ± 6.0%, median 20.4% and mean ± SD 6.9% ± 6.6%, median 1.6%, respectively. There were 156 deaths during the observation period. In best-fit models, predictors of death included increasing GA, increasing age, presence of peripheral vascular disease, decreasing serum albumin, and decreasing hemoglobin concentrations. HbA(1c) and random serum glucose concentrations were not predictive of survival. Increasing GA levels were associated with hospitalization in the 17 days after measurement, whereas HbA(1c) was not. CONCLUSIONS: In contrast to the HbA(1c) and random serum glucose values, GA accurately predicts the risk of death and hospitalizations in patients with diabetes mellitus and ESRD. The GA assay should be considered by clinicians who care for patients with diabetes on dialysis.

Basic performance of an enzymatic method for glycated albumin and reference range determination.

BACKGROUND: Glycated albumin (GA) is a medium-term glycemic control marker of diabetes and may be more sensitive to changes in plasma glucose than hemoglobin A1c. We studied where and how many fructosyl groups bind to albumin, and which glycation sites are measured by the enzymatic method for GA. We also studied the basic performance of the enzymatic method for GA. METHODS: Glycated albumin was measured using an enzymatic method (Lucica®GA-L, Asahi Kasei Pharma) on a biochemical autoanalyzer. Molecular weights of purified GA and nonglycated albumin were measured by a mass spectrometry system. Two hundred one healthy volunteers with normal results of oral glucose tolerance testing were recruited to determine the reference range in Americans. RESULTS: The present method measured only glycated amino acids from albumin in serum protein. We estimate that the number of glycated amino acids measured by this method was approximately two per molecule of albumin. The general performance (sensitivity, specificity, reproducibility, linearity, interference) of the method was good. The reference range of GA% in Americans with normal glucose tolerance was determined to be 11.9-15.8% (mean ± 2 standard deviations). Significant differences were not observed between the sexes; however, race differences were observed (higher levels in blacks relative to whites). CONCLUSIONS: The method was specific for measuring glycated amino acids in albumin and had good basic performance characteristics. The reference range in Americans was 11.9-15.8%. This method may be a useful indicator for diabetes control.

Relationship between assays of glycemia in diabetic subjects with advanced chronic kidney disease.

BACKGROUND: Relative to hemoglobin A(1c) (HbA(1c)), glycated albumin (GA) more accurately reflects recent glycemic control in diabetic patients on hemodialysis and peritoneal dialysis. These assays have yet to be compared in patients with advanced chronic kidney disease (CKD). METHODS: HbA(1c) and GA were simultaneously measured in 303 diabetic subjects: 70 with CKD prior to dialysis (CKD-stage 4), 184 with CKD after transplantation (TXP-stage 3) and 49 non-nephropathy controls. RESULTS: Mean estimated GFR was 76, 46 and 26 ml/min in controls, TXP-3 and CKD-4 cases, respectively. Mean (SD) HbA(1c) (%) and GA (%) concentrations were 7.30 (1.40) and 16.8 (4.9) in controls, 7.28 (1.66) and 21.5 (6.4) in CKD-4 cases, and 7.21 (1.62) and 21.2 (5.5) in TXP-3 cases, respectively. The GA:HbA(1c) ratio differed significantly between non-nephropathy controls and both groups of CKD patients (both p < 0.001), but not between CKD-4 and TXP-3 cases (p = 0.92). The glucose:HbA(1c) ratio was inversely associated with GFR in all 254 nephropathy cases (r = -0.13; p = 0.04), while glucose:GA did not vary significantly based upon GFR (r = -0.08; p = 0.24). CONCLUSIONS: The relationship between glycated albumin and HbA(1c) is influenced by the presence of reduced GFR in diabetic patients with CKD. The accuracy of the HbA(1c) assay in diabetic subjects with severe nephropathy requires further investigation, although HbA(1c) performs relatively well with milder CKD.

Comparison of glycated albumin and hemoglobin A1c concentrations in diabetic subjects on peritoneal and hemodialysis.

BACKGROUND: Relative to hemoglobin A(1c) (HbA(1c)), percentage of glycated albumin (GA%) more accurately reflects recent glycemic control in diabetic hemodialysis (HD) patients. METHODS: To determine the accuracy of glycemic assays in a larger sample including patients on peritoneal dialysis (PD), HbA(1c) and GA% were measured in 519 diabetic subjects: 55 on PD, 415 on HD, and 49 non-nephropathy controls. RESULTS: Mean +/- SD serum glucose levels were higher in HD and PD patients relative to non-nephropathy controls (HD 169.7 +/- 62 mg/dL, PD 168.6 +/- 66 mg/dL, controls 146.1 +/- 66 mg/dL; p = 0.03 HD vs controls, p = 0.13 PD vs controls). GA% was also higher in HD and PD patients (HD 20.6% +/- 8.0%, PD 19.0% +/- 5.7%, controls 15.7% +/- 7.7%; p < 0.02 HD vs controls and PD vs controls). HbA(1c) was paradoxically lower in dialysis patients (HD 6.78% +/- 1.6%, PD 6.87% +/- 1.4%, controls 7.3% +/- 1.4%; p = 0.03 HD vs controls, p = 0.12 PD vs controls). The serum glucose/HbA(1c) ratio differed significantly between dialysis patients and controls (p < 0.0001 HD vs controls, p = 0.002 PD vs controls), while serum glucose/GA% ratio was similar across groups (p = 0.96 HD vs controls, p = 0.64 PD vs controls). In best-fit multivariate models with HbA(1c) or GA% as outcome variable, dialysis status was a significant predictor of HbA(1c) but not GA%. CONCLUSIONS: The relationship between HbA(1c) and GA% differs in diabetic patients with end-stage renal disease who perform either PD or HD compared to those without nephropathy. HbA(1c) significantly underestimates glycemic control in peritoneal and hemodialysis patients relative to GA%.

[Task-orientated therapy (target-therapy) directed to patients with renal cell carcinoma].

Two main ways playing a cardinal role in the pathogenesis of metastatic renal cell carcinoma (mRCC) have been identified in recent years, they are following: 1) a way of the mutation of a gene suppressor VHL (Van-Hippel-Lindau), stimulating various types of tyrosine-kinases participating in the development of tumors; 2) mTOR way, where ramapycyn plays a leading role, which effect proliferation and angiogenesis of mRCC. This discovery enabled the development of a new generation of highly effective medications for target-therapy of mRCCC--tyrosine-kinases inhibitors (VEGFR-1, VEGFR-2, VEGFR-3, PDGFR-alpha/PDGFR-beta, Raf-kinases, etc.) sunitimab, sorafenib, pazopanib, axitinib, etc. and mTOR inhibitors--everolimus and temsirolimus as well as monoclonal neutralising antibody VEGF (bevasizumab). The review is devoted to the analysis of antitumor activity, patient tolerance and side effect of these preparations in the system therapy of patients with mRCC.

[The level of circulating cytokines and chemokines in the preclinical and early clinical stages of type IA diabetes mellitus development].

AIM: to study the level of circulating proinflammatory (IL-1alpha, IL-1beta, IL-6, alpha-TNF, IFN-gamma) and anti-inflammatory (IL-4, IL-10) cytokines and chemokines (IL-8, IL-16) in preclinical development of type 1A diabetes mellitus (T1DM) in children. SUBJECTS AND METHODS: An examination was made in 450 children who had normal blood glucose levels and a burdened history of positive or negative Langerhans islet autoantibodies (LIAA): IAA, GADA, and 1A-2A over time until the clinical manifestations of DM1 emerged. The levels of the cytokines and chemokines were determined by ELISA and the titer of LIAA was by radioimmunoassay. RESULTS: Long before T1DM was clinically diagnosed, most children with normal blood glucose levels and LIAA had elevated levels of the cytokines IL-1alpha, IL-6, and alpha-TNF and the chemoattractants IL-8 and IL-16 with lower IL-4 concentrations as compared with the similar indices in children without LIAA and controls. After the disease manifested, the magnitude of changes in the indices under study reduced in the majority of children with LIAA, which may suggest that the autoimmune process subsides after destruction of most beta-cells. CONCLUSION: The elevated levels of IL-6, IL-16, alpha-TNF, and the chemokine IL-8 with the lower blood content of the cytokine IL-4 were long before the development of DM1 in children with normal blood glucose level in the presence of LIAA, which should be borne in mind while developing the immune mechanisms specifically directed against block, which participate by means of cytokines in beta-cell destruction, as well as methods for preventing the development of T1DM in subjects with LIAA.

[Hormones of adipose tissue in diabetes mellitus and its complications (review of literature and the authors'own data)].

The contemporary ideas on endocrine function of the adipose tissue and its role in pathogenesis of diabetes mellitus and insulin resistance associated with it and the metabolic syndrome are shown in the review. A change in the life style (excessive and irrational nutrition, insufficient physical loading, psychological disorders) and also the reduction of genetic and immunologic controlling mechanisms contribute to the development of obesity, that is now considered as low-grade inflammation. An increased number of small size adipocytes and macrophages of the adipose tissue begin to secrete an increase number of proinflammatory adipocytokines and chemokines that result in the inflammatory and metabolic stress accompanied by the stimulation of signal pathways, leading to increased insulin requirement, on the one hand, and promoting to the beta-cell death, on the other hand. The role of some adipocytokines such as IL-6, TNF-alpha, leptin, adiponectin, visfatin and resistin was demonstrated in these processes.

Enhanced detection in capillary electrophoresis: example determination of serum mycophenolic acid.

In order to overcome the poor absorbency detection limits in CE, two simple strategies were combined to increase the amount of the sample injected: a long capillary to hold extra sample while leaving adequate room for the separation and acetonitrile stacking, which concentrated the sample based on transient pseudo-ITP. The combination of these two strategies yielded sensitivity comparable or better than that of the HPLC with good separation and with better theoretical plate number. The analysis of mycophenolic acid, a common immunosuppressant drug, in serum was used here as an example to illustrate this enhanced detection and its applicability to therapeutic drug monitoring. Acetonitrile was used to remove serum proteins followed by direct injection filling 5-21% of the capillary volume and separation in a borate buffer. The overall CE method compared well to an assay by HPLC as far as sample preparation, correlation coefficient, and especially sensitivity of detection.

A chronic iron-deficient/high-manganese diet in rodents results in increased brain oxidative stress and behavioral deficits in the morris water maze.

Iron deficiency (ID) is especially common in pregnant women and may even persist following childbirth. This is of concern in light of reports demonstrating that ID may be sufficient to produce homeostatic dysregulation of other metals, including manganese (Mn). These results are particularly important considering the potential introduction of the Mn-containing gas additive, methyl cyclopentadienyl manganese tricarbonyl (MMT), in various countries around the world. In order to model this potentially vulnerable population, we fed female rats fed either control (35 mg Fe/kg chow; 10 mg Mn/kg chow) or low iron/high-manganese (IDMn; 3.5 mg Fe/kg chow; 100 mg Mn/kg chow) diet, and examined whether these changes had any long-term behavioral effects on the animals' spatial abilities, as tested by the Morris water maze (MWM). We also analyzed behavioral performance on auditory sensorimotor gating utilizing prepulse inhibition (PPI), which may be related to overall cognitive performance. Furthermore, brain and blood metal levels were assessed, as well as regional brain isoprostane production. We found that treated animals were slightly ID, with statistically significant increases in both iron (Fe) and Mn in the hippocampus, but statistically significantly less Fe in the cerebellum. Additionally, isoprostane levels, markers of oxidative stress, were increased in the brain stem of IDMn animals. Although treated animals were indistinguishable from controls in the PPI experiments, they performed less well than controls in the MWM. Taken together, our data suggest that vulnerable ID populations exposed to high levels of Mn may indeed be at risk of potentially dangerous alterations in brain metal levels which could also lead to behavioral deficits.

Rapid quantitation of hemoglobin S in sickle cell patients using the Variant II Turbo analyzer.

A rapid ( approximately 90 sec), fully automated method is described for quantifying hemoglobin S (HbS) by high performance liquid chromatography (HPLC) using the Bio-Rad Variant II Turbo analyzer. Although this instrument is designed to quantify only blood hemoglobin A1c (HbA1c), we show that it can also quantify accurately, without modification, HbS levels in sickle cell patients, provided the blood samples meet certain conditions. The samples should contain detectable hemoglobin F (HbF), but should not contain hemoglobin C (HbC). Under these conditions, blood HbS levels obtained by this method correlate well with those obtained by agarose electrophoresis (r(2) = 0.97, n = 81 patients). We also show that quantitation of blood HbF in sickle cell patients is more accurate by this method than by agarose electrophoresis when the HbF level is in the range from 0.2 to 10%.

Analysis of immune complexes by capillary electrophoresis.

A simple method for immune complexes (IC) analysis by CE is described. This method combines the ease of precipitation of the IC by polyethylene glycol with the separation power of CE. The advantage of this method is a better quantitation of the IC, since it corrects and eliminates the interferences from other serum proteins. It also reveals the composition (monoclonality) of the precipitate. Three types of IC have been detected in this method: monoclonal, polyclonal and mixed (mono-polyclonal) IC. Furthermore, the method is rapid and simple.

Direct injection of organic solvent extracts for capillary electrophoresis.

It is demonstrated here that organic solvents immiscible in water used in sample extraction, such as chloroform, can be injected directly and successfully on the capillary without the need for evaporation and reconstitution. Current continuity was maintained all the time during the run. In order to avoid the rapid evaporation of the organic solvent during the analysis, the aqueous layer was left over the chloroform. This simplified the extraction step, and enabled the injection from the same vial over several hours without dealing with problem of evaporation. The relative peak heights in the electropherograms can be modified by the inclusion in the chloroform of a more polar solvent, by adjusting the pH, or adjusting the salt content of the sample. Addition of a polar solvent to the chloroform improved greatly the precision of the analysis for both the peak height and migration time.

[Circulating interleukin-16 in blood of patients with metabolic syndrome and type 2 diabetes mellitus].

The authors determined interleukin-16 (IL-16) content in blood serum of patients distributed into three groups using an immunoenzymic method (ELISA). The first group consisted of patients with type 2 DM and metabolic syndrome (MS); the second group with type 2 DM and without MS, the third group - with MS and without T2DM. The control group consisted of normoglycemic subjects without MS signs who were distributed into two subgroups: 1) with excessive weight; 2) with normal weight. A significant increase in IL-16 concentration in blood serum was noted in patients with T2DM associated with MS (249,5+/-75,3 pg/ml) versus patients with MS without T2DM (130,5+/-41,2 pg/ml), and versus patients with T2DM without MS (69,5+/-35,6 pg/ml, P<0,05) and without obesity (77,4+/-11,6 pg/ml, P<0,05). This increase correlated with abdomen volume (r=0,4, P<0,05) and triglyceride level (r=0,4, P<0,05).

Cryoglobulins: an important but neglected clinical test.

Cryoglobulin (CR) denotes a serum immunoglobulin that precipitates at temperatures below 37 degrees C and dissolves on re-warming. CRs are heterogeneous in chemical composition and behave differently in vivo and in vitro. The majority are mixed antigen-antibody complexes that occur with high incidence in autoimmune and infectious disorders. Their measurement is important in the management of patients with vasculitis. CRs elicit variable symptoms in patients, mostly purpura, weakness, and arthralgias, and they require various methods of treatment. Sometimes CRs are not associated with any symptoms; but they can be associated with very severe conditions such as nephropathy and neuropathy. Treatment depends on the symptoms and causes, and on the phenotyping of the CR. Considering the high incidence of CR in diseases such as hepatitis C virus (HCV) infection, together with the high worldwide prevalence of this disease, it is clear that testing for CR is underutilized in clinical practice. CR testing has been neglected in routine clinical laboratories and by clinicians due to several factors, such as the lengthy time for serum CR analysis and failure to appreciate that low levels of CR can be associated with severe symptoms. In a series of 194 serum samples that gave positive tests for CR at our institution, the majority contained low CR concentrations (65% of the samples were type II with a mean of 372 mg/L and 39% of type III with a mean of 216 mg/L; reference range 0-60 mg/L). Case studies are presented to illustrate the importance of such low levels of CR. There is a need for more rapid and more reliable methods for quantification and phenotyping of low concentrations of serum CR. Based on our experience in the routine analysis, quantification, and phenotyping of serum CR, some practical solutions to these problems are presented.

[The immunity during the pre-clinical period of type I diabetes mellitus].

The purpose of the study was to investigate the condition of immunity (blood lymphocyte immune phenotype and ultrastructure) in healthy children with a family background of type 1 diabetes mellitus (DM 1) having or not having diabetes-associated autoantibodies (DAAB). The subjects of the study were divided into three groups. Group 1 consisted of 90 children with a family background of DM 1 (first line relatives had DM 1), DAAB- (GADA, IA-2A, and IAA) positive or negative; group 2 consisted of 51 children with newly revealed DM 1; group 3 included 45 healthy controls, normoglycemic DAAB-negative children with no family background of DM 1. GADA, IA-2A, and IAA titers were measured using radioimmunoassay. The immune phenotype of lymphocytes (CD3+, CD4+, CDr8, CD20+, and CD56+ cells) were studied using flow cytometry (FACS-analysis); their ultrastructure was studied by means of electron microscopy. The study found a significantly lower total number of T-lymphocytes (CD3+ cells), T-helpers/inductors (CD4+ cells), and natural killer cells (CD56+ cells and large granule-containing lymphocytes) in the DAAB-positive children vs. the DAAB-negative ones and especially the controls. In the DAAB-positive children, electron microscopy found distinct changes in the ultrastructure of CD4+ lymphocytes and large granule-containing lymphocytes (CD56+ cells), which evidences changes in the secretory and cytostatic function. Such changes in the number and ultrastructure of these lymphocyte subpopulations are found in patients with newly revealed DM 1. Thus, immune changes happen in the organism of a healthy person a long time before clinical manifestations of DM 1 develop; these changes reflect a concealed autoimmune process in Langerhans islets. Detection of DAAB plays a significant role not only in studying poorly understood pre-diabetes nature, but also in the development of new, scientifically based methods of its prevention and treatment.

Direct analysis of hydrogen peroxide by capillary electrophoresis.

A method is described for analysis of hydrogen peroxide directly by CZE in borate buffer based on its absorption in UV light at 185 nm, without reaction with dyes. The absorption at 185 nm was about 3.5 times better than that at 214 nm. Hydrogen peroxide was generated enzymatically from glucose in aqueous solutions and in serum and was removed by the catalase enzyme. To improve the sensitivity of detection, samples were concentrated on the capillary based on stacking by ACN. The method is rapid (approximately 7 min) and specific.