Estimated arterial stiffness and cardiovascular risk in chronic kidney disease – a study protocol

Introduction The prevalence of chronic kidney disease (CKD) in the general population is 9.1%. Cur- rent guidelines recommend a cut-off GFR value of 60 mL/min/1.73 m2 for diagnosis of CKD, without considering the physiological decline of GFR with aging, or the association with cardiovascular (CV), cerebrovascular or renal outcomes. There is also an increase in arterial stiffness with aging, which is es- timated by pulse wave velocity (PWV). Aim The aim of this study is to show how the ePWV predicts CV incidents independently of SCORE chart and traditional risk factors. Materials and Methods This prospective observational study will include 2058 subjects from the Endemic nephropathy in Croatia – epidemiology, diagnosis and etiopathogenesis scientific research project. Conclusion This will be the first study that could show how the estimated arterial stiffness, independently of CKD contributes to overall CV, cerebrovascular and renal risk. We could also, based on the results, propose an age-independent definition of CKD based on the association with CV disease and mortality

Effect of ecological conditions on expression of biopomological characteristics of chestnut (Castanea sativa Mill.) in natural populations of Montenegro

This paper presents the five-year long research results (2007-2011) of phenological observations (beginning, full flowering and the end of flowering), morphometric analysis (fruit weight, length, width and thickness of fruit, as well as length and width of the hilum), the ripening time and the average yield of selected genotypes of sweet chestnut (Castanea sativa Mill.). The results show that in terms of time of flowering chestnut trees examined in the group are very early flowering. The ripening of studied chestnut trees shows that the earliest harvest tree was Ostros II, VII and Kostajnica V (09.11.), and Kostajnica III (14.11.) were the latest. The average fruit weight of the selected sweet chestnut trees was (6.9 g). The highest average fruit weight (10.6 g), had the examined Ostros I tree, and the lowest (4.8 g), Kostajnica VI. The yield of the tested chestnut trees was on average (76.3 kg / tree). The selected trees Kostajnica II (66.0 kg / tree), Kostajnica I (69.0 kg / tree) had the smallest yield and Ostros VI (94.0 kg / tree) and Ostros V (87.0 kg / tree) had the highest. Obviously it can be concluded that population genetic variability is very high and gene expression is highly affected in tested samples on both locations. For further research it should be given attention to investigate genotypes in controlled conditions, the best in vitro in tissue culture. [Projekat Ministarstva nauke Republike Srbije, br. TR-20013 i br. TR-31064

The cropping and productivity potencial of peach cultivars introduced early epoch maturation

Assortment of peach is very dynamic. Many new varieties registered each year in Italy, France, USA and other countries. Introduction of a permanent process imposes the need to study newly varieties in certain environmental conditions to determine their economic and biological characteristics, to recommend the best production practices for intensive cultivation. Investigations were carried out in production-test plantation AD "Plantations" - Agrokombinat "13 July" in Podgorica in the period 2005-2009. year. Tests included seven newly introduced varieties of peaches and nectarines (Early Crest, Early May Crest, May Crest, Qwin Cest, White Crest, Rita Star and Andrew) and two standard varieties (Spingbelle and Royal Glory). In these cultivars to investigate major biological properties: blossom, pollen, fruit, ripening time and yield. Investigated peaches on average flourished in the range of 3.11 (Rita Star) to 19.03. (Qwin Crest and White Crest). The best germination of pollen had a variety Early May Crest (85.66%), and the smallest variety Crest White(74.00%). Fruit set on average in all the varieties was (87.00%), the largest recorded in the variety May Crest (95.30%) and lowest (79.33%) had a variety of White Crest. Yield of most varieties of peaches is balanced by age, and volume are in the group of low to high productivity

Assessing the impact of synthetic inertia controls in DFIG wind turbines on small-signal stability

Tilstedeværelsen av fornybare energikilder, spesielt vindkraft, øker raskt i kraftsystemet. Bruk av vindturbiner medfører også utfordringer, da rotasjonshastigheten til store vindturbiner reguleres for å oppnå maksimal effektutvinning fra vinden. Hastighetsreguleringen forårsaker frakobling mellom den mekaniske rotasjonen til vindturbinen og den elektriske frekvensen til kraftsystemet. Frakoblingen fører til at økende implementering av vindkraft i kraftsystemet reduserer systemets treghetsmoment og svekker frekvensstabiliteten. En populær løsning på treghetsreduksjonen er syntetiske treghetsregulatorer. Dette er en manipulasjonsteknikk i effektreferansen til vindturbinen. Regulatoren forårsaker raske og potensielt betydelige effektendringer. Referansemanipulasjonen er gjennom en derivator proporsjonal med endringen i frekvens og gjennom rotasjonshastigheten proporsjonal med kinetisk energi lagret i vindturbinens rotasjon. Regulatoren får vindturbinen til å gi en effekt ved frekvensendringer som ligner på responsen til en synkrongenerator, som motvirker frekvensendringer. Det forventes å finne flere og flere av disse syntetiske treghetsregulatorene i kraftsystemet i tiden som kommer. Raske, referansebaserte kraftelektronikk-omformere vil påvirke kraftsystemets stabilitet. Denne masteroppgaven undersøker hvordan DFIG-vindturbiner med frekvenskontrollere, inkludert syntetiske treghetsregulatorer, påvirker kraftsystemets småsignal-stabilitet. Vindturbinteknologien i fokus er type 3, dobbelmatet induksjonsgenerator. ''Kundur’s two-area system'' brukes til analysen, der en av synkrongeneratorene byttes til vindkraft. Et testsystem er utviklet i DIgSILENT PowerFactory, hvor vindturbinmodellen er utviklet fra DFIG vindturbinmalen, hentet fra DIgSILENT-biblioteket. En komplett frekvenskontroller er designet, bestående av syntetisk treghet- og primærkontroll. Omfattende modellverifisering er utført ved å rekonstruere modellen i programvaren Matlab Simulink. Til tross for enkelte modelleringsforskjeller i programvarene, oppnås en høy grad av korrespondanse mellom egenverdiprofilene. Dette bidrar til å verifisere kraftsystem- og vindturbinmodelleringen. Flere følsomhetsanalyser utføres for vindkraft uten frekvenskontroll og synkron-generering. Dette brukes til å undersøke roten av egenverdibevegelsen til de ulike syntetiske treghetsregulator-analysene, samt gi bedre forståelse rundt DFIG-vindturbiners påvirkning på systemets stabilitet. Uten frekvenskontroll svekker vindturbinene småsignal-stabiliteten, spesielt dempingen av mellomområde-modusen, forårsaket av DFIG-kontrollsystemet. Ved å inkludere frekvenskontrolleren i vindturbinene forbedres småsignal-stabiliteten, og den svekkede påvirkningen på mellomområde-modusen reverseres. Vindturbinene både skaper og påvirker små oscillerende egenverdier, spesielt ved bruk av syntetiske treghetsregulatorer. Derivatoren i treghetsregulatoren har en høy påvirkning på egenverdiene i systemet. En reduserende tidskonstant i derivatoren vil bedre etterligne formen til treghetsbidraget fra en synkrongenerator, men også etterligne økende synkrongenerator-treghet mot systemets egenverdier. Derfor kan en syntetisk treghetsregulator med de riktige parameterne påvirke systemets egenverdier med ønsket treghet, og samtidig gi frekvensstøtte gjennom et treghetsbidrag i samsvar med den lagrede kinetiske energien i vindturbinens rotasjon

Bone mineral density in children with juvenile idiopathic arthritis after one year of treatment with etanercept

Introduction/Objective. Juvenile idiopathic arthritis (JIA) is the most frequent chronic inflammatory, rheumatic disease of childhood, associated with disturbance of bone mineral metabolism, which develops gradually and progressively, and if untreated eventually leads to osteoporosis in adulthood. The aim of our study was to evaluate bone mineral density (BMD) in patients with JIA treated with etanercept over a period of one year. Methods. The prospective cohort study included 94 JIA patients (66 female, 28 male), their median age being 14.77 years. BMD was measured by dual-energy X-ray absorptiometry on the lumbar spine. Disease activity was assessed using the American College of Rheumatology Pedi 50 criteria. Results. After one year of treatment with etanercept, we found a statistically significant increment in all osteodensitometry variables (p < 0.001). Annual enhancement for the whole group was as follows: bone mineral content 15.8%, BMD 7.2%, BMDvol 4.2%. Z-score improved from -0.86 to -0.58 SD at the last visit, but decreased in rheumatoid factor-positive polyarthritis patients. Patients with systemic JIA had the lowest Z-score. Z-score correlated with functional disability level. BMD was lower in the group treated with glucocorticoids. Conclusion. Our results showed significant improvement of bone mineral density in children with JIA after one year of treatment with etanercept. Rheumatoid factor-positive and systemic JIA subtypes and treatment with glucocorticoids are the risk factors for impairing bone mineral metabolism

Biocompatibility and antibiofilm activity of graphene-oxide functionalized titanium discs and collagen membranes

The aims of the study were: 1) to evaluate the effect on biofilm formation of barrier membranes and titanium surfaces coated with graphene-oxide (GO); 2) to analyze the connection between the superficial topography of the tested materials and the amount of bacterial accumulation on them and 3) to analyze the biocompatibility of GO functionalized discs using the zebrafish model. Methods: Single species bacterial biofilms (Streptococcus oralis, Veilonella parvula, Fusobacterium nucleatum, Porphyomonas gingivalis) were grown on GO-free membranes, membranes coated with 2 and 10 μg/ml of GO, GO-free and GO-coated titanium discs. The biofilms were analyzed by determining the CFU count and by Scanning Electron Microscopy (SEM) and the materials’ topography by Atomic Force Microscopy (AFM). Zebrafish model was used to determine the materials’ toxicity and inflammatory effects. Results: AFM showed similar roughness of control and GO-coated materials. CFU counts on GO-coated discs were significantly lower than on control discs for all species. CFU counts of S. oralis, V. parvula and P. gingivalis were lower on biofilms grown on both types of GO-coated membranes than on GO-free membrane. SEM analysis showed different formation of single species biofilm of S. oralis on control and GO-coated materials. GO-functionalized titanium discs do not induce toxic or inflammatory effects. Significance: Titanium implant surfaces functionalized with GO have shown to be biocompatible and less susceptible to biofilm formation. These results encourage further in vivo investigation of the tested materials on infection prevention, specifically in prevention and reduction of peri-implant mucositis and periimplantitis incidence

Abdominal localization of unicentric form of Castleman disease: A case report

Introduction. Castleman disease is a rare disease of the unknown etiology, occuring in two clinical forms: unicentric or multicentric. It is characterized by the hyperplasia of lymph glands. In literature the four pathohistological forms were described: hyaline vascular type, plasma cell type, mixed type and a recently recognized plasmablastic type. The most frequent changes are localized in the mediastinum, while the abdominal localization is with significatly rare occurrence, and that was the motive for presentation of this case. Case report. In a 41-year old male magnetic resonance (MR) enterography showed a change in the ileocecal area without the presence of subjective symptoms of digestive tract and without loss of body mass. Due to the suspicion of stromal tumor, surgical intervention was indicated. Pathohistological findings showed Castleman lymphadenopathia reactiva mesenterii (plasma cell type) which was in the unicentric form. There were present only anaemia and the increased value of sedimentation from the laboratory analyses. Conclusion. Abdominal localization of unicentric plasma cell form occurs rarely and the surgical method of treatment presents the golden standard as it was shown in the presented case

Association of multiple retinal nodular hamartomas and "confetti" skin lesions with end-stage renal disease in patients with tuberous sclerosis

Purpose: The main purpose of this study is to explore characteristics of patients with chronic kidney disease in tuberous sclerosis (TSC) and to underline differences in clinical characteristics between end-stage renal disease (ESRD) patients and patients in earlier stages of chronic kidney disease. Methods: This multicentric, retrospective study included data for 48 patients from seven South-Eastern European countries (Albania, Bosnia and Herzegovina, Croatia, Greece, Montenegro, Serbia, Slovenia) in the period from February to August 2020. Researchers collected data from local and national nephrological and neurological registries and offered clinical and laboratory results from medical histories in follow-up periods. Results: This study enrolled 48 patients with a median age of 32.3 years (range, 18-46 years), and predominant female gender (60.45%). The percentage of patients with chronic kidney disease (CKD) diagnosis of the total number of patients was 66.90%, with end-stage renal disease development in 39.6%. The most prevalent renal lesions leading to chronic kidney disease were angiomyolipomas (AMLs) in 76.6%, while multiple renal cysts were present in 42.6% of patients. Nephrectomy was performed in 43% of patients, while the mTOR inhibitors were used in 18 patients (37.5%). The majority of patients had cutaneous manifestations of tuberous sclerosis-83.30% had hypomelanotic cutaneous lesions, and 68.80% had angiofibromas. Multiple retinal nodular hamartomas and "confetti" skin lesions were more frequent in end-stage renal disease (ESRD) than in patients with earlier stages of chronic kidney disease (p-0.033 and 0.03, respectively). Conclusion: Our study has also shown that retinal hamartomas and "confetti" skin lesions are more frequent in end-stage renal diseases (ESRD) patients than in other chronic kidney disease (CKD) patients. Usage of mTOR inhibitors can also reduce the number of complications and associated with tuberous sclerosis, such as dermatological manifestations and retinal hamartoma, which are more common in the terminal stage of chronic kidney disease