Evaluation of thermal plasma process for treatment disposal of solid radioactive waste.

The management of radioactive waste is a worldwide activity based on the guidelines of the International Atomic Energy Agency (IAEA), and all stages of management require scientifically proven methods for possible deployment. The management of radioactive waste is a huge challenge due to the high risk in the collection, gathering, transport, handling, and storage. In this study, a thermal plasma treatment process was evaluated for its efficiency to process solid radioactive waste. Experiments were carried out with the application of stable isotopes of Lead, Iodine, Cobalt, and Cesium. After the thermal plasma treatments, the slag and the residual gas were analyzed to verify the influence of process time and discharge power on the efficiency of the process. The treatment for 25 min and 10 kW was sufficient to reduce the mass by 50% of the slag. When the applied power was increased to 15 kW, an expressive reduction in the treatment time (10 min) was able to promote the same mass reduction. The results indicated that the treatment of radioactive waste by thermal plasma is a promising method to manage and reduce the mass and volume for the final disposal.

The accessory heads of the muscles flexor pollicis longus and flexor digitorum profundus (Gantzer muscle) - An anatomical study in Brazilian cadavers.

An important accessory anatomical variation, exclusively human, and related to the muscular ventres of the flexor pollicis longus and flexor digitorum profundus is frequently denominated Gantzer. These variations have close relations with the anterior interosseous nerve (AIN), which provides, for many authors, by direct compression, one of the rare neuropathic syndromes. In this work, thirty-four forearms were dissected from the collections of the Medical School of the Federal University of Minas Gerais and the Department of Basic Sciences of the Federal University of Juiz de Fora, with a prevalence of 50% of the 34 forearms studied for the Gantzer muscle. The muscle relationship was mainly with the flexor pollicis longus muscle and only one occurrence related to the flexor digitorum profundus muscle, described as a rare occurrence of unilateral double formation of Gantzer muscle. Bilaterality was observed in 88.23% of the findings and the dominant innervation for this muscle variation occurred in 82.35% by the anterior interosseous nerve (AIN). The type morphological in all forms found was the fusiform, with 10.5cm of total length and an average of 0.3cm in diameter and all related, as origin, in the medial aspect of the coronoid process of the ulna, next to the origin of the flexor digitorum superficialis muscle. Our work largely reflected the findings of most publications and, considering the controversy of the occurrence of a compressive neuropathy, the data were not sufficient, from a strictly anatomical point of view, to confirm or refute the hypothesis.

Activation of C-C motif chemokine receptor 2 modulates testicular macrophages number, steroidogenesis, and spermatogenesis progression.

The monocyte chemoattractant protein 1 (MCP-1) belongs to the CC chemokine family and acts in the recruitment of C-C motif chemokine receptor 2 (CCR2)-positive immune cell types to inflammation sites. In testis, the MCP-1/CCR2 axis has been associated with the macrophage population's functional regulation, which presents significant functions supporting germ cell development. In this context, herein, we aimed to investigate the role of the chemokine receptor CCR2 in mice testicular environment and its impact on male sperm production. Using adult transgenic mice strain that had the CCR2 gene replaced by a red fluorescent protein gene, we showed a stage-dependent expression of CCR2 in type B spermatogonia and early primary spermatocytes. Several parameters related to sperm production were reduced in the absence of CCR2 protein, such as Sertoli cell efficiency, meiotic index, and overall yield of spermatogenesis. Daily sperm production decreased by almost 40%, and several damages in the seminiferous tubules were observed. Significant reduction in the expression of important genes related to the Sertoli cell function (Cnx43, Vim, Ocln, Spna2) and meiosis initiation (Stra8, Pcna, Prdm9, Msh5) occurred in comparison to controls. Also, the number of macrophages significantly decreased in the absence of CCR2 protein, along with a disturbance in Leydig cell steroidogenic activity. In summary, our results show that the non-activation of the MCP-1/CCR2 axis disturbs the testicular homeostasis, interfering in macrophage population, meiosis initiation, blood-testis barrier function, and androgen synthesis, leading to the malfunction of seminiferous tubules, decreased testosterone levels, defective sperm production, and lower fertility index.

Is there a physiological variability for albumin excretion rate? Study in patients with diabetes type 1 and non-diabetic individuals.

BACKGROUND: To determine the intraindividual coefficient of variation (CV(i)) of albumin excretion rate (AER). METHOD: We studied 76 patients with type 1diabetes and 66 non-diabetic subjects (ND) under routine clinical conditions providing three timed overnight urine samples for urinary albumin determination by radioimmunoassay. RESULTS: Patients and ND had similar CV(i) of AER (50.7+/-33.3 vs. 58.1+/-33.2% P=0.12). Intermittent microalbuminuric subjects (one out of 3 AER >20 microg/min) had higher CV(i) of AER than normoalbuminuric and persistent microalbuminuric patients, [84.9 (37.1-145. 3) vs. 39.8 (4.9-124.8) vs. 34.6 (12.1-116.5)% P=0.0007] without difference between the two latter groups. In patients, the independent factor associated with the CV(i) of AER in multiple regression analysis was age (r(2)=0.08; P=0.01). Sensitivity (95% CL) and specificity of first AER for diagnosing microalbuminuria was 85.7% (42.0-99.2) and 91.3% (81.4-96.4). CONCLUIONS: Our findings suggest the variability of AER was physiological, unrelated to diabetic condition. First AER could be used for screening of microalbuminuria followed by a second one when the patient has AER >20 microg/min in the first. This would result in low cost for screening and diagnosis of microalbuminuria, that is not always feasible in routine clinical practice in developing countries using three urine samples.

Ambulatory blood pressure monitoring and microalbuminuria in normotensive subjects with insulin-dependent diabetes mellitus.

OBJECTIVE: To assess the association between microalbuminuria with ambulatory blood pressure monitoring in normotensive individuals with insulin-dependent diabetes mellitus. METHODS: Thirty-seven patients underwent determination of the rate of urinary excretion of albumin through radioimmunoassay and ambulatory blood pressure monitoring. Their mean age was 26.5+/-6.7 years, and the mean duration of their disease was 8 (1-34) years. Microalbuminuria was defined as urinary excretion of albumin > or =20 and <200 microg/min in at least 2 out of 3 urine samples. RESULTS: Nine (24.3%) patients were microalbuminuric. Ambulatory blood pressure monitoring in the microalbuminuric patients had higher mean pressure values, mainly the systolic pressure, during sleep as compared with that in the normoalbuminuric patients (120.1+/-8.3 vs 110.8+/-7.1 mmHg; p=0.007). The pressure load was higher in the microalbuminuric individuals, mainly the systolic pressure load during wakefulness [6.3 (2.9-45.9) vs. 1.6 (0-16%); p=0.001]. This was the variable that better correlated with the urinary excretion of albumin (r(S)=0.61; p<0.001). Systolic pressure load >50% and diastolic pressure load > 30% during sleep was associated with microalbuminuria (p=0.008). The pressure drop during sleep did not differ between the groups. CONCLUSION: Microalbuminuric normotensive insulin-dependent diabetic patients show greater mean pressure value and pressure load during ambulatory blood pressure monitoring, and these variables correlate with urinary excretion of albumin.

Prospective study of development of microalbuminuria and retinopathy in Brazilian IDDM patients.

With the aim to study potential risk factors for the development of microalbuminuria and retinopathy, baseline characteristics were examined in 50 Brazilian IDDM patients followed for 4.48 years with a 2-year reexamination. During the study, 3 patients (6%) aged 25.9 +/- 4.4 years, duration of diabetes 8.1 +/- 4.2 years, died from acute complications without microalbuminuria and retinopathy after a follow-up of 2.1 +/- 0.7 years. The standardized mortality rate for the group was 0.84 per 1000 (95% CL, 0.31, 1.83) in comparison to 0.14 per 1000 in the general population. From 34 normoalbuminuric individuals at baseline (urinary albumin excretion rate (AER) < or = 20 micrograms/min in > or = 2 overnight urine collections), 10 developed microalbuminuria with an incidence density of 6.5 cases per 100 person-years (95% CL, 2.23, 10.16). Spontaneous normalization of AER was found in 2 of 4 patients with microalbuminuria at cycle 2. Multiple stepwise regression analysis demonstrated that baseline AER (p = 0.03), but not glycated hemoglobin, blood pressure or duration of diabetes, predicted end-of-study AER. From 36 patients without retinopathy, 10 developed nonproliferative retinopathy with an incidence density of 6.6 cases per 100 person-years (95% CL, 2.75, 10.54). Retinopathy was associated with duration (p = 0.05) and age at diagnosis of diabetes (p = 0.01). A tendency with baseline AER (p = 0.06) was also noted. No patient developed macroalbuminuria, proliferative retinopathy or hypertension. By the end of our study, in a cohort of young IDDM patients followed in a developing country, 6% died from acute complications and 15 patients (44.1%) developed retinopathy and/or microalbuminuria. Our results suggest that the only predictor of end-of-study AER was baseline AER. Also, duration of diabetes and age at diagnosis appear to be risk factors for retinopathy.

Residual beta-cell function and microvascular complications in type 1 diabetic patients.

To determine the influence of residual beta-cell function on retinopathy and microalbuminuria we measured basal C-peptide in 50 type 1 diabetic outpatients aged 24.96 +/- 7.14 years, with a duration of diabetes of 9.1 +/- 6.2 years. Forty-three patients (86%) with low C-peptide (<0.74 ng/ml) had longer duration of diabetes than 7 patients (14%) with high C-peptide (> or =0.74 ng/ml) (9 (2-34) vs 3 (1-10) years, P = 0.01) and a tendency to high glycated hemoglobin (HBA1) (8.8 (6-17.9) vs 7.7 (6.9-8.7)%, P = 0. 08). Nine patients (18%) had microalbuminuria (two out of three overnight urine samples with an albumin excretion rate (AER) > or =20 and <200 microg/min) and 13 (26%) had background retinopathy. No association was found between low C-peptide, microalbuminuria and retinopathy and no difference in basal C-peptide was observed between microalbuminuric and normoalbuminuric patients (0.4 +/- 0.5 vs 0.19 +/- 0.22 ng/ml, P = 0.61) and between patients with or without retinopathy (0.4 +/- 0.6 vs 0.2 +/- 0.3 ng/ml, P = 0.43). Multiple regression analysis showed that duration of diabetes (r = 0. 30, r2 = 0.09, P = 0.031) followed by HBA1 (r = 0.41, r2 = 0.17, P = 0.01) influenced basal C-peptide, and this duration of diabetes was the only variable affecting AER (r = 0.40, r2 = 0.16, P = 0.004). In our sample of type 1 diabetic patients residual ss-cell function was not associated with microalbuminuria or retinopathy.

Residual ß-cell function and microvascular complications in type 1 diabetic patients

To determine the influence of residual ß-cell function on retinopathy and microalbuminuria we measured basal C-peptide in 50 type 1 diabetic outpatients aged 24.96 + or - 7.14 years, with a duration of diabetes of 9.1 + or - 6.2 years. Forty-three patients (86 percent) with low C-peptide (<0.74 ng/ml) had longer duration of diabetes than 7 patients (14 percent) with high C-peptide (<0.74 ng/ml) (9 (2-34) vs 3 (1-10) years, P = 0.01) and a tendency to high glycated hemoglobin (HBA1) (8.8 (6-17.9) vs 7.7 (6.9-8.7)percent, P = 0.08). Nine patients (18 percent) had microalbuminuria (two out of three overnight urine samples with an albumin excretion rate (AER)> or - 20 and <200 µg/min) and 13 (26 percent) had background retinopathy. No association was found between low C-peptide, microalbuminuria and retinopathy and no difference in basal C-peptide was observed between microalbuminuric and normoalbuminuric patients (0.4 + or - 0.5 vs 0.19 + or - 0.22 ng/ml, P = 0.61) and between patients with or without retinopathy (0.4 + or - 0.6 vs 0.2 + or - 0.3 ng/ml, P = 0.43). Multiple regression analysis showed that duration of diabetes (r = 0.30, r2 = 0.09, P = 0.031) followed by HBA1 (r = 0.41, r2 = 0.17, P = 0.01) influenced basal C-peptide, and this duration of diabetes was the only variable affecting AER (r = 0.40, r2 = 0.16, P = 0.004). In our sample of type 1 diabetic patients residual ß-cell function was not associated with microalbuminuria or retinopathy

Synthesis and in vitro evaluation of potential antichagasic dipeptide prodrugs of primaquine.

American trypanosomiasis (Chagas' disease) is an endemic parasitic disease afflicting more than 20 million people in Latin America. Currently, therapy is unsatisfactory and only two drugs are available. Primaquine, an antimalarial drug, has trypanocidal activity. Dipeptide derivatives of primaquine, Phe-Arg-PQ, Lys-Arg-PQ, and Phe-Ala-PQ, were synthesized. The choice of the peptides was based on the primary specificity of cruzipain, the major cysteine proteinase from T cruzi. The prodrugs obtained were tested on the LLC-MK2 cell culture infected with trypomastigotes forms of T. cruzi. Phe-Arg-PQ, Lys-Arg-PQ, and Phe-Ala-PQ were active in all stages.

Microalbuminuria and associated clinical features among Brazilians with insulin dependent diabetes mellitus.

With the objective to determine the frequency of microalbuminuria, macroalbuminuria and the associated clinic and metabolic features among insulin dependent diabetes mellitus (IDDM) Brazilian patients attending at a general University Hospital, a total of 50 outpatients, aged 21.9 +/- 7 years with IDDM duration of 6.8 +/- 5.8 years were studied cross-sectionally. Urinary albumin excretion rate (AER) was determined in timed overnight urine samples. Microalbuminuria was defined when two out of three urine samples had AER ranging 20-200 micrograms/min. Microalbuminuria was present in 12% of our patients. No macroalbuminuric patient was found. Among patients with diabetes duration < or = 5 years (n = 24), 8.3% (n = 2) had microalbuminuria. Retinopathy was strongly associated with microalbuminuria (P = 0.004) although no proliferative retinopathy was noted. No difference was observed concerning FBG and HBAI between normo and microalbuminuria patients. Univariate analysis has revealed no influence of these variables in AER. Systolic blood pressure (sBP) was high in microalbuminuria patients and stepwise multiple regression analysis has shown that it was the only significant independent variable to influence AER. (R = 0.42 r2 = 0.18 P = 0.002). In conclusion, the frequency of microalbuminuria in this sample of IDDM Brazilian patients was similar to other populational groups and was associated with retinopathy and sBP.

Influence of first morning urine volume, fasting blood glucose and glycosylated hemoglobin on first morning urinary albumin concentration.

The aim of the present study was to evaluate the effect of first morning urinary volume (collected on three different non-consecutive days), fasting blood glucose (determined on the first and third days of urine collection), and glycosylated hemoglobin (determined on the first and third days of urine collection) on the albumin concentration in first morning urine samples collected on three different days. We found 3.6% asymptomatic bacteriuria in the urine samples; therefore, every urine sample must be tested to exclude infection. One hundred and fifty urine samples were provided by 50 IDDM patients aged 21.9 +/- 7 (12-38) years with a disease duration of 6.8 +/- 5.8 (0.4-31) years attending the Diabetes Clinic at the State University Hospital of Rio de Janeiro. There were no differences in albumin concentration (6.1 vs 5.8 vs 6.2 micrograms/ml; P = NS) or urinary volume (222.5 vs 210 vs 200 ml) between the three samples. In addition, there were no differences in fasting blood glucose (181.9 +/- 93.6 vs 194.6 +/- 104.7 mg%; P = NS) or glycosylated hemoglobin (HbA1) (8.4 +/- 1.3 vs 8.8 +/- 1.5%; P = NS) between the first and third blood samples. Six patients (group 1) had a mean urinary albumin concentration of more than 20 micrograms/ml for the three urine samples. This group was compared with the 44 patients (group 2) with a mean urinary albumin concentration for the three urine samples of less than 20 micrograms/ml. No difference was found between groups 1 and 2 in relation to fasting blood glucose (207.1 +/- 71.7 vs 187.6 +/- 84.6 mg/dl), HbA1 (8.1 +/- 0.9 vs 8.6 +/- 1.1%) or urinary volume [202 (48.3-435) vs 246 (77.3-683.3) ml]. Stepwise multiple regression analysis with albumin concentration of first morning urine samples as the dependent variable, and urinary volume, fasting blood glucose and glycosylated hemoglobin as independent variables, showed that only 12% (P = 0.01) of the albumin concentration could be accounted for by the independent effect of morning urine volume on the first day of urine collection. No urine samples showed a change in the cutoff level of 20 micrograms/ml of albumin concentration as the result of volume. Fasting blood glucose and glycosylated hemoglobin did not influence the urinary albumin concentration. Considerable variability in urinary albumin concentration was found in the three morning urine samples with a mean intraindividual coefficient variation of 56%. In conclusion, in the present study, urinary volume had a minimal, though not constant, effect on first morning urinary albumin concentration. Day-to-day metabolic and clinical control of IDDM patients, except probably for ketoacidosis, should not contraindicate microalbuminuria screening in first morning urine samples.

Influence of first morning urine volume, fasting blood glucose and glycosylated hemoglobin on first morning urinary albumin concentration

The aim of the present study was to evaluate the effect of first morning urinary volume (collected on three different non-consecutive days), fasting blood glucose (determined on the first and third days of urine collection), and glycosylated hemoglobin (determined on the first and third days of urine collection) on the albumin concentration in first morning urine samples collected on three different days. We found 3.6 per cent asymptomatic bacteriuria in the urine samples; therefore, every urine sample must be tested to exclude infection. One hundred and fifty urine samples were provided by 50 IDDM patients aged 21.9 ñ 7 (l2-38) years with a disease duration of 6.8 + 5.8 (0.4-31) years attending the Diabetes Clinic at the State University Hospital of Rio de Janeiro. There were no differences in albumin concentration (6.1 vs 5.8 vs 6.2 mug/ml; P = NS) or urinary volume (222.5 vs 210 vs 200 ml) between the three samples. In addition, there were no differences in fasting blood glucose (181.9 + 93.6 vs 194.6 + 104.7 mg per cent; P = NS) or glycosylated hemoglobin (HbA 1) (8.4 ñ 1.3 vs 8.8 ñ 1.5 per cent; P = NS) between the first and third blood samples. Six patients (group 1) had a mean urinary albumin concentration of more than 20 mug/ml for the three urine samples. This group was compared with the 44 patients (group 2) with a mean urinary albumin concentration for the three urine samples of less than 20 mug/ml. No difference was found between groups 1 and 2 in relation to fasting blood glucose (207.1 ñ 71.7 vs 187.6 ñ 84.6 mg/dl), HbA 1 (8.1 ñ 0.9 vs 8.6 ñ 1.1 per cent) or urinary volume [202 (48.3-435) vs 246 (77.3-683.3) ml]. Stepwise multiple regression analysis with albumin concentration of first morning urine samples as the dependent variable, and urinary volume, fasting blood glucose and glycosylated hemoglobin as independent variables, showed that only 12 per cent (P = 0.01) of the albumin concentration could be accounted for by the independent effect of morning urine volume on the first day of urine collection. No urine samples showed a change in the cutoff level of 20 mug/ml of albumin concentration as the result of volume. Fasting blood glucose and glycosylated hemoglobin did not influence the urinary albumin concentration. Considerable variability in urinary albumin concentration was found in the three morning urine samples with a mean intraindividual coefficient variation of 56 per cent. In conclusion, in the present study, urinary volume...

Trypanosoma cruzi: shedding of surface antigens as membrane vesicles.

Tissue culture-derived trypomastigotes from Trypanosoma cruzi spontaneously shed surface antigens into the culture medium. The shedding is a temperature- and time-dependent phenomenon and is independent of the presence of proteins or immune serum in the medium. The analysis of this process in four strains (Y, YuYu, CA1, and RA) showed differences in the amounts of polypeptides released. However, for all strains the liberation of the entire set of surface polypeptides ranging in molecular mass from 70 to 150 kDa was observed. Biochemical and electron microscopic data strongly suggest that most of the surface antigens are released as plasma membrane vesicles, ranging from 20 to 80 nm in diameter.

The N-linked carbohydrate chain of the 85-kilodalton glycoprotein from Trypanosoma cruzi trypomastigotes contains sialyl, fucosyl and galactosyl (alpha 1-3)galactose units.

The structure of the N-linked oligosaccharide of the 85-kDa surface glycoprotein (Tc-85) from the infective trypomastigote form of Trypanosoma cruzi was investigated. Tc-85 metabolically labeled with [14C]glucose was purified by affinity chromatography on wheat germ agglutinin-Sepharose. Binding to the lectin was lost on treatment of Tc-85 with neuraminidase. The N-linked asialo-oligosaccharide was released by endo-beta-N-acetylglucosaminidase F digestion of asialo-Tc-85 and was further analyzed using specific exoglycosidases. [14C]fucose was detected after alpha-L-fucosidase treatment or mild acid hydrolysis. The afucosyl oligosaccharide was 3H-labeled by the galactose oxidase-NaB3H4 method. [3H]Galactose was released by alpha-galactosidase, and only then was beta-galactosidase effective in removing another galactose. The gal(alpha 1-3)gal unit was demonstrated by periodate oxidation studies on the [3H]galactose-labeled asialo-glycoprotein. The presence of gal(alpha 1-3)gal in Tc-85 could be related to the recent finding of elevated antibody levels against this epitope in patients with Chagas' disease.

cAMP phosphodiesterase and activator protein of mammalian cAMP phosphodiesterase from Trypanosoma cruzi.

Epimastigote forms of Trypanosoma cruzi contain a soluble cAMP phosphodiesterase. Optimal activity was found at pH 8.0 and in the presence of 5 mM Mn2+. Other cations were less efficient and did not give rise to an additional stimulation when added in the presence of optimal concentrations of Mn2+. The enzyme is not Ca2+ dependent. The apparent Km of the enzyme for the substrate is 40 microM and no kinetic evidence for the existence of two enzymes has been found. Theophylline and caffein did not inhibit the T. cruzi cAMP phosphodiesterase. The enzyme activity does not change during cell growth suggesting that the fluctuation observed in the levels of cAMP are largely a response to variations in adenylyl cyclase activity. The intracellular concentrations of cAMP ranged between 0.04--0.15 microM. No evidence that the T. cruzi cAMP phosphodiesterase is regulated by an endogenous activator could be found. However, T. cruzi contains a heat-stable, low molecular weight, non-dialysable protein that activates mammalian cAMP phosphodiesterase in the presence of Ca2+. The properties so far studied of such an activator suggest that it might be equivalent to other Ca2+-dependent regulators described in vertebrate and invertebrate species.