IDENTIFYING VOLTAGE AND FREQUENCY REGULATION CURVES OF SELF-EXCITED INDUCTION GENERATOR

A simple method for computation of voltage and frequency regulation curves of a self-excited induction generator is presented in this paper. The method has been successfully exploited for identifying several different types of regulation curves of a 1.5 kW cage rotor self-excited induction generator. The proposed approach is universal and can be used for identification of any generator’s regulation curves, if the parameters of the equivalent circuit are known. Information contained in these computed curves can be very useful while designing systems for automatic control of self-excited induction generators

Whole exome resequencing reveals recessive mutations in TRAP1 in individuals with CAKUT and VACTERL association

Congenital abnormalities of the kidney and urinary tract (CAKUT) account for approximately half of children with chronic kidney disease and they are the most frequent cause of end-stage renal disease in children in the US. However, its genetic etiology remains mostly elusive. VACTERL association is a rare disorder that involves congenital abnormalities in multiple organs including the kidney and urinary tract in up to 60% of the cases. By homozygosity mapping and whole exome resequencing combined with high-throughput mutation analysis by array-based multiplex PCR and next-generation sequencing, we identified recessive mutations in the gene TNF receptor-associated protein 1 (TRAP1) in two families with isolated CAKUT and three families with VACTERL association. TRAP1 is a heat shock protein 90-related mitochondrial chaperone possibly involved in antiapoptotic and endoplasmic reticulum-stress signaling. Trap1 is expressed in renal epithelia of developing mouse kidney E13.5 and in the kidney of adult rats, most prominently in proximal tubules and in thick medullary ascending limbs of Henle’s loop. Thus, we identified mutations in TRAP1 as highly likely causing CAKUT or CAKUT in VACTERL association

Chronic kidney disease during a 12-year period at tertiary health institution

Introduction. Chronic kidney disease (CKD) is a significant cause of morbidity and mortality in paediatric population. Objective. The aim of the study was analysis of aetiology, staging and associated complications of CKD at the time of diagnosis. Methods. Data of 97 patients (56 boys) of average age 7.8±5.8 years, referred for the first time to the Institute for Mother and Child Healthcare „Dr Vukan Čupić”, Belgrade in the period 1998- 2009, due to CKD, stage 2-5, were analysed. In each patient illness history was obtained, and physical examination, laboratory, X-ray and other investigations were performed according to the indications. CKD was classified according to the glomerular filtration rate into four grades: 2 - mild (60-90 ml/min/1.73 m2); 3 - moderate (30-60 ml/min/1.73 m2); 4 - advanced (15-30 ml/ min/1.73 m2); and 5 - terminal (<15 ml/min/1.73 m2). Results. The most frequent causes of CKD were congenital anomalies of the kidney and urinary tract (43.3%), followed by glomerular diseases (17.5%), hereditary kidney diseases (16.5%), metabolic diseases (7.2%) and other causes (15.5%). Mild CKD was found in 29.8%, moderate in 28.9%, advanced in 22.7%, and terminal in 18.6% children. Among patients with CKD stage 4 and 5, 75% of patients presented with acute renal failure, while 25% had earlier detected CKD (stage 1), but were not under regular follow-up. Associated complications included metabolic acidosis (63%), anaemia (60%), hypertension (42.3%), short stature (25.8%), renal osteodystrophy (13.4%) and cardiovascular diseases (7.2%). Conclusion. Congenital anomalies of the kidney and urinary tract are the leading cause of CKD in paediatric population. A significant proportion (41.3%) of patients had advanced and terminal CKD. In most patients CKD was diagnosed late and with associated complications

Evaluation of heavy metals and radionuclides in fish and seafood products

Despite the existence of a legislation regarding food contaminants, food safety control in Serbia is a matter of great concern. This study investigates the radioactivity levels and heavy metal concentrations in fish and seafood commercially available in Serbian markets. Domestic fish species (caught in the Danube River)and fishery products imported from Europe, Asia and America were analyzed. The content of natural radionuclides and 137 Cs were investigated by gamma spectrometry. Activity concentration of 40 K was measured in the range of 44–165 Bq kg −1 ; low levels of 137 Cs were detected in two samples (2.8 and 3.0 Bq kg −1 ), while concentrations of 226 Ra and 232 Th were below minimal detectable values. Concentrations of heavy metals (Cd, Hg and Pb)were determined using ICP-OES method. Cd concentration ranged from 0.01 to 0.81 mg kg −1 in sea fish and from 0.01 to 0.03 mg kg −1 in freshwater fish. Hg concentrations were in the range of 0.01–1.47 mg kg −1 ; the highest value was measured in the predator fish - shark. The highest level of Pb (6.56 mg kg −1 )was detected in a blue sea fish (Atlantic mackerel). The health risks associated with the intake of heavy metals and radionuclides via fish consumption were evaluated. The results indicate that fish and seafood consumption do not pose a significant health concern in the case of the usual consumption rate which is typical for the population of Serbia. However, a highly frequent consumption of fishery products can have adverse health effects, especially due to Hg and Pb contamination.Peer-reviewed version: [http://cer.ihtm.bg.ac.rs/handle/123456789/2944

Chronic kidney disease in TARS2-related mitochondrial disease – A case report

This case report describes a patient harboring TARS2 mutations where chronic kidney disease stands out as the predominant clinical feature. The distinct manifestation observed in this case underscores the importance of continual exploration and documentation of diverse clinical presentations associated with TARS2 mutations, contributing to an enriched comprehension of the spectrum of effects linked to this genetic variatio

Atypical presentation of cystic fibrosis: Obese adolescent with hypertension and pseudo-Bartter’s syndrome

Introduction. Infants with cystic fibrosis may fail to thrive despite recommended caloric intake because of electrolyte disurbances caused by salt depletion resulting in hypochloremic metabolic alkalosis or pseudo-Bartter's syndrome. In most patients reported symptoms began in infancy, but it may be an initial presentation of disease in a previously healthy adolescent. Case report. A 15-year-old boy was admitted for evaluation of recurrent episodes of malaise associated with dehydration and acute renal insufficiency. Laboratory analysis showed hypochloremic metabolic alkalosis with hyponatremia and hypokalemia. On admission the boy was obese, with body weight of 95.5 kg (> P97), height 174 cm (> P75), and body mass index of 31.2 kg/m2 (> P95). Physical examination was inconclusive. Blood pressure holter monitoring proved significant systolic hypertension. Routine urinalysis, protein and electrolyte levels in urine were normal. Plasma renin and aldosteron were normal. Sweat chloride concentration was 63 mmol/L. Genetic testing confirmed the diagnosis of cystic fibrosis. Conclusion. To our knowledge, this is the first reported case of atypical presentation of cystic fibrosis in an adolescent presented with pseudo-Bartter's syndrome and signs of obesity and hypertension. We suggest that every patient with hypochloremic metabolic alkalosis should be evaluated for cystic fibrosis

Is Kragujevac city still a "hot spot" area, twenty years after the bombing?

After NATO bombing of Serbia in 1999, UNEP has identified Kragujevac as one of the four heavily polluted environmental "hot spots". Damaging of industrial and military targets caused the release of substantial amounts of hazardous chemical substances into the environment. This study was conducted in order to access the exposure of residents of Kragujevac city to persistent soil pollutants, twenty years after NATO air campaign. The paper reports the results of measuring radionuclides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, and Hg) in soil samples collected from two depths (0-15 cm and 15-30 cm) at 30 locations along the riverbank of the Lepenica River. The average specific activities of Ra-226, Th-232, K-40 and Cs-137 were comparable to average worldwide values; excess lifetime cancer risk (ELCR) from natural radionuclides ranged from 1.1.10(-4) to 3.3.10(-4). The measured concentrations of As, Co, Cr, Cu, and Ni exceeded the limit values in most of the samples. Non-carcinogenic risk (hazard quotient and hazard index) and carcinogenic risk from heavy metals were assessed. Total hazard index was 0.257 and 2.16 for adults and children, respectively. Sum of measured PAHs ranged from 110 to 1026 mu g kg(-1). Sum of PCBs exceeded the limit value of 20 mu g kg(-1) in all samples (it ranged from 48.8 to 196.8 mu g kg(-1)), but it was still below the remediation level. The differences between two layers with respect to all measured variables were not statistically significant

The utilisation of grapeseed oil in improving the quality of dry fermented sausages

This study aims to examine the scope of changes in colour, texture and sensory characteristics of fermented sausages by substituting 20% of backfat with grapeseed oil prepared as liquid (GS), encapsulated (EGS) and pre-emulsified [with soy protein isolate (GSI) and alginate (GSA)], and their stability during 30days of refrigerated storage. Protein and fat contents, pH and TBA values were not significantly different between products after production and storage. Treatments with added oil had higher weight loss (1.5-2.5%), while moisture content was significantly lowest in GS. Internal product colour evaluation showed the highest values of L*, b* and hue angle in GSI. GSI had the highest hardness and chewiness. Storage affected more surface than internal product colour, hardness was significantly changed only in GSI (lower) and EGS (higher), and increasing of TBA did not lead to significant differences between treatments. The study showed that GSA was the most promising of all treatments investigated

Corticosteroid-responsive nephrotic syndrome in children with myelodysplastic syndromes

Several reports have documented various forms of glomerular diseases in adults with myelodysplastic syndromes (MDS), but similar reports in children are lacking. We describe two children with MDS-associated with steroid-responsive nephrotic syndrome (NS). Patient 1, who had MDS with myelofibrosis, presented also hepatosplenomegaly, pancytopenia, chronic hepatitis, moderate proteinuria, hypocomplementemia and elevated ANA titer. During initial prednisone treatment proteinuria markedly diminished and partial but transient haematological improvement occurred. Relapse subsequently occurred that was manifested by overt NS and pancytopenia. High doses of prednisolone led to remission of the renal disease but haematological remission did not occur. Persisting pancytopenia and repeated infections terminated in sepsis, two years after the onset of MDS. Patient 2, who had refractory anemia with clonal monosomy 19, manifested bowel disease, hepatospleno- megaly, anaemia and non-organic specific autoantibodies. Prednisone led to both clinical and haematological remission. Haematologic disease relapsed 12 months later, when nephrotic-range proteinuria, haematuria and mild azotaemia were also found. Corticosteroid treatment led to long-lasting renal and haematologic remission, maintained by a small dosage of prednisone. In both patients renal biopsy findings were consistent with those seen in idiopathic NS. A Medline search disclosed 16 cases of glomerulopathy in the course of MDS in adult patients. Clinical features included NS, usually accompanied by renal insufficiency with either acute, chronic, or rapidly progressive glomerulonephritis. On biopsy, membranous nephropathy, crescentic or mesangial proliferative glomerulonephritis and AL amyloidosis, were found. We conclude: (1) that glomerular disease may be present and should be searched for in patients with MDS; (2) that MDS can be added to the list of rare conditions associated with corticosteroid-responsive NS in children