Genetički polimorfizmi paraoksonaze 1 i podložnost aterogenezi

Introduction. Paraoxonase 1 (PON1) is a multifunctional enzyme associated with high-density lipoprotein particles (HDL). It is a cellular antioxidant that hydrolyses oxidized macromolecules, especially low-density lipoproteins (ox-LDL). Because increased oxidative stress is believed to play a crucial role in the initiation and propagation of atherosclerosis, coding (Q192R and L55M) and promoter (C(-107)T) region polymorphisms of pon1 gene, that are responsible for catalytic efficiency, activity and the level of the enzyme, have been of great interest as a potential markers of susceptibility for atherogenesis. Objective. The aim of the study was to assess possible association between these pon1 gene variants and clinical manifestations of the atherosclerosis and oxidative stress. Methods. A total of 60 angiographically documented patients with manifested atherosclerotic disease and 100 control individuals were analyzed. Genomic DNA was isolated from the peripheral blood cells and genotyping was performed using polymerase chain reaction followed by the restriction fragment length polymorphism (PCR-RFLP) analysis. Results No significant difference in allele and genotype frequencies of all three examined polymorphisms was found between the atherosclerotic patients and healthy controls. The obtained results could not support an association of pon1 gene variants with the oxidative stress and atherogenesis. Conclusion. These polymorphisms cannot be considered risk factors of atherosclerosis in Serbian population. A larger study is required in order to establish possible contribution of pon1 variants to atherosclerosis-related cardiovascular diseases.Uvod. Paraoksonaza 1 (PON1) je multifunkcionalni enzim koji je vezan za lipoproteine visoke gustine (HDL). To je ćelijski antioksidans koji hidrolizuje oksidovane makromolekule, naročito oksidovane lipoproteine niske gustine (ox-LDL). Smatra se da povišeni oksidativni stres igra ključnu ulogu u inicijaciji i propagaciji ateroskleroze, pa su polimorfizmi u kodirajućem (Q192R i L55M) i promotorskom (C(-107)T) regionu gena pon1, koji su odgovorni za katalitičku efikasnost, aktivnost i nivo enzima, od velikog interesa kao potencijalni markeri osetljivosti na aterogenezu. Cilj rada. Cilj ove studije je bio da se ispita moguća povezanost varijanti gena pon1 i kliničkih manifestacija ateroskleroze i oksidativnog stresa. Metode rada. Analizirano je 60 bolesnika s angiografski dokumentovanim manifestacijama ateroskleroze i 100 zdravih ispitanika. Genomska DNK je izolovana iz ćelija periferne krvi, a genotipizacija je urađena primenom reakcije lančane polimeraze, posle koje je urađena analiza dužine restrikcionih fragmenata (tzv. PCR-RFLP analiza). Rezultati. Učestalosti alela i genotipova tri ispitivana polimorfizma nisu pokazale značajne razlike između ispitanika obolelih od ateroskleroze i zdravih osoba. Dobijeni rezultati ne ukazuju na povezanost analiziranih varijanti gena pon1 i oksidativnog stresa i aterogeneze. Zaključak. Ovi polimorfizmi se ne mogu smatrati faktorima rizika za razvoj ateroskleroze u srpskoj populaciji. Potrebna je studija sa većim brojem ispitanika, kako bi se utvrdio mogući doprinos varijanti gena pon1 na nastanak kardiovaskularnih oboljenja u čijoj osnovi je ateroskleroza

Orthodontic treatment of nongrowing patient with class II division 2 malocclusion by Herbst appliance

Background. Inheritance is most casual etiological factor of Class II division 2 malocclusion. This kind of malocclusion is very difficult for treatment specially in older patients. Case report. In the female patient, 20 years old, at the beginning of the treatment at the School of Dentistry in Belgrade, lateral cephalogram showed skeletal and dentoalveolar Class II division 2 malocclusion. She was in the Herbst treatment for 8 months and 12 months more with a fixed multibracket appliance. The measurements were performed on lateral cephalograms before and after the treatment: ii, is, mi, ms, Pg and ss. The distance from these points to occlusal perpendicular line (Olp) were measured and compared from cephalogram before to cephalogram after the treatment. Temporomandibular joint (TMJ) tomograms were compared from before and after the treatment by superimposition. Correction was found in molar and incisor relation, overjet and overbite. There were found sagital skeletal changes and soft tissue profile improvement. Conclusion. Herbst appliance is effective in the treatment of Class II malocclusions, even in adult patients. Dental and skeletal changes as a result of Herbst treatment could be good choice instead of camouflage orthodontics or surgical decision

Surface modification of TiO2 nanoparticles with catechol

Surface modification of nanocrystalline TiO2 particles with catechol was found to result in a red shift of the semiconductor absorption compared to unmodified nanocrystallites. The undercoordinated defect sites at TiO2 surface are the source of novel enhanced and selective reactivity of the nanoparticle toward bidentate ligand binding. Catechol, an enediol ligand, have the optimal geometry for chelating surface Ti atoms, resulting in a five-membered ring coordination complex and restoration of six-coordinated octahedral geometry of surface Ti atoms.Physical chemistry 2008 : 9th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 200

The effect of surgical treatment of morbid obesity on functional capacity and risk factors for cardiovascular diseases

Introduction: Morbid obesity is associated with elevated risk of cardiovascular disease (CVD). Bariatric surgery is the most effective weight loss method for morbidly obese patients. Aim: To examine the effect of surgical treatment of morbid obesity on functional capacity and risk factors for CVD. Material and Methods: In a group of 56 morbidly obese patients Body Mass Index (BMI), functional capacity and risk factors for CVD were compared before and after laparoscopic gastric bypass surgery. BMI was derived from the patients' weight and height. Functional capacity parameters (peak VO2 and VE/VCO2 slope) and systolic (SBP) and diastolic (DBP) blood pressure were obtained during ergospirometry testing. Data on risk factors was acquired from medical histories and laboratory analyses. Results: A statistically significant difference was found in peak VO2 (p<0.0001) and VE/ VCO2 slope (p =0.003) before and 6 months after the surgery. Resting SBP significantly decreased (p=0.017), as did SBP in maximal effort (p<0.0001). Similar results were observed when comparing resting and maximal effort DBP (p<0.0001 and p=0.002, respectively) before and after the surgery. Risk factors for CVD improved - hypercholesterolemia (12,5% vs 9%), diabetes (37% vs 19,6%) and hypertension (48,2% vs 33%). Conclusion: Morbidly obese patients showed an improvement of functional capacity, as well as in the risk factors for CVD 6 months following laparoscopic gastric bypass surgery

Controlled synthesis and optical properties of Ag nanoparticles

Nanosized hydrophobic, oleylamine stabilized silver (Ag) organosols were obtained in the reaction between the related metal salt and oleylamine in various organic solvents. The obtained hydrophobic colloids are stable and retain same particles morphology even after solvent evaporation and redispersion of the dried deposit in chloroform. The sizes of the Ag nanoparticles can be controlled from 8 to 25 nm by reaction temperatures. The position and shape of the surface plasmon resonance band depends upon the size and shape of Ag nanoparticles as well as dielectric constant of the medium

Encapsulation of Horseradish Peroxidase into Poly(D,L-Lactide) by the Modified Precipitation Method

Poster presented at PHYSICAL CHEMISTRY 2008. 9th International Conference on Fundamental and Applied Aspects of Physical Chemistry, Belgrade, September 24-26, 200

Preparation and Characterization of Poly-D,L-Lactide Microspheres for Controlled Release of Horseradish Peroxidase as Model Protein

Poster presented at the 10th Conference of the Materials Research Society of Serbia - YUCOMAT 2008, Herceg Novi, Crna Gora, 8-12. septembar 2008

Combined treatment with ribavirin and tiazofurin attenuates response of glial cells in experimental autoimmune encephalomyelitis

Experimental autoimmune encephalomyelitis (EAE) is an animal model of multiple sclerosis (MS), a human inflammatory and demyelinating disease. Microglia and astrocytes are glial cells of the central nervous system (CNS) that play a dual role in MS and EAE pathology. The aim of this study was to examine the effect of combined treatment with two nucleoside analogues, ribavirin and tiazofurin, on microglia and astrocytes in actively induced EAE. Therapeutic treatment with a combination of these two nucleoside analogues reduced disease severity, mononuclear cell infiltration and demyelination. The obtained histological results indicate that ribavirin and tiazofurin changed activated microglia into an inactive type and attenuated astrocyte reactivity at the end of the treatment period. Since reduction of reactive microgliosis and astrogliosis correlated with EAE suppression, the present study also suggests that the obtained beneficial effect of ribavirin and tiazofurin could be a consequence of their action inside as well as outside the CNS. [Acknowledgments. This work was supported by the Serbian Ministry of Education and Science, Project No: III41014.

Zavisnost između percepcije bola kod pacijenata sa šest različitih ortodontskih žica i teskobe zubnih nizova

Introduction Forces generated in orthodontic treatment with fixed appliances create tension and compression zones in the periodontal ligament resulting in a painful experience for patients. In the first phase of orthodontic treatment, when leveling of teeth is needed, nickel-titanium (NiTi) archwires can be completely engaged in brackets, even in the cases of extreme crowding, exerting small forces. There is a great individual variation in the pain perception related to the application of orthodontic forces. Objective The aim of this study was to investigate the pain perception among patients with dental crowding after insertion of six different NiTi orthodontic archwires as a part of fixed appliances in the first stage of orthodontic treatment. Methods The study was conducted on a sample of 189 orthodontic patients receiving one of six different either superelastic or heat activated NiTi archwires, in the first phase of orthodontic treatment. Pain perception was evaluated in groups of patients with different degree of crowding. The modified McGill Pain Questionnaire with Visual Analogue Scale was used to evaluate the quality and intensity of pain. Statistical analysis was performed using simple descriptive statistics, and Pearson's chi-square test with statistical significance of p lt 0.05. Results Majority of patients reported pain as discomfort or pressure of moderate intensity caused by chewing or biting, started within 12 hours, carried on for 3-4 days, and decreased over time without self-medication. Conclusion No correlation was found between pain perception among patients with different types of NiTi archwires and the degree of crowding.Uvod Ortodontske sile kojima se tokom terapije fiksnim aparatima pomeraju zubi dovode do istezanja i kompresije parodontalnih vlakana, te pojave bola kod pacijenata. U prvoj fazi ortodontskog lečenja, kada se zubi nivelišu, žice od legure nikl-titanijuma proizvode relativno malu silu i mogu se potpuno ligirati u slotove bravica, čak i u slučajevima velike teskobe. Postoje veoma velike individualne varijacije u percepciji bola prilikom primene ortodontskih sila. Cilj rada Cilj istraživanja je bio da se ispita percepcija bola kod osoba s teskobom u zubnim nizovima nakon ligiranja šest različitih ortodontskih žica u sklopu prve faze terapije fiksnim aparatima. Metode rada Studija je urađena na uzorku od 189 pacijenata kojima je u okviru ortodontskog lečenja fiksnim aparatima bila ligirana jedna od šest različitih superelastičnih ili termo žica od legure nikl-titanijuma. Percepcija bola je procenjivana kod osoba s različitom izraženošću teskobe. Korišćen je modifikovani Makgilov (McGill) upitnik za bol s Vizuelnom analognom skalom radi opisivanja kvaliteta i intenziteta bola. Statistička obrada podataka je obuhvatila deskriptivnu statističku analizu i primenu h2-testa sa statističkom značajnošću od p lt 0,05. Rezultati Najveći broj ispitanika je opisao bol kao neprijatnost ili pritisak srednjeg intenziteta izazvan žvakanjem ili dodirom, koji je počinjao do 12 sati od ligiranja žice, trajao je tri-četiri dana i smanjivao se bez primene lekova. Zaključak Nije utvrđena statistički značajna razlika u percepciji bola kod osoba s različitom izraženošću teskobe zubnih nizova kojima su bile ligirane superelastične i termo žice od legure nikl-titanijuma

Dentoalveolarni terapijski efekti Herbst aparata i aktivatora kod osoba u postpubertetskom uzrastu sa malokluzijom klase II/1

Background/Aim. Functional appliances can be used effectively in the treatment of skeletal Class II/1 malocclusions. The best treatment results are obtained during active period of facial growth when skeletal, as well as dentoalveolar, changes occur. In comparison with removable functional appliances, such as activator, that are effective only during adolescent period of growth, the Herbst fixed appliance is also successful at the end of the growth period. It also offers a shorter treatment time and a patient compliance is not necessary. The aim of this study was to analyze and compare dentoalveolar changes in the group of young adult patients with Class II/1 malocclusion treated with the Herbst appliance and an activator. Methods. The sample for this study consisted of 50 patients of both sexes, 14-21 years of age with Class II/1 malocclusion. For estimating the effect of functional appliances used, the following cephalometrics parameters were determined: inclination of the upper and lower incisors, interincisal angle, antero-posterior molars relationships, overjet and overbite. The results obtained were statistically tested. Results. The cephalometric findings after the treatment indicated retroinclination of upper incisors (average value of 9°) and proclination of lower incisors (average value of 7°), mostly expressed in the patients treated by Herbst appliance (p lt 0.001). Increased overjet and distocclusion were completely corrected in the group of patients treated with the Herbst appliance, while the correction of malocclusion in the activator group was only partially accomplished. No changes in the overbite were noticed at the end of the treatment in both groups. Conclusion. The results of this study revealed that the Herbst appliance is more effective in the treatment of Class II/1 malocclusion in young adults in comparison with the activator.Uvod/Cilj. Funkcionalni aparati uspešno se koriste u terapiji malokluzija klase II/1. Najbolji rezultati postižu se terapijom u periodu pubertetskog skoka rasta, kada su moguća najveća skeletna i dentoalveolarna pomeranja. U poređenju sa terapijom pokretnim funkcionalnim aparatima, kao što je aktivator prema Andresen-u, terapija Herbst-ovim fiksnim aparatom (Herbst aparat), uspešna je i nakon pubertetskog skoka rasta, vreme terapije je kraće, a bolesnike ne treba motivisati za saradnju jer je aparat fiksiran na zubima. Cilj istraživnja bio je da se kod bolesnika mlađeg odraslog uzrasta sa malokluzijom klase II odeljenja 1 uporede efekti fiksnog funkcionalnog Herbst aparata i pokretnog aktivatora na dentoalveolarne strukture. Metode. Ispitivanje je obuhvatilo 50 bolesnika sa malokluzijom klase II/1, oba pola, uzrasta 14-21 godine. Efekti primenjenih funkcionalnih aparata, aktivatora prema Andresen-u i Herbst aparata, procenjivani su na osnovu parametara merenih na profilnim telerendgenskim snimcima, nagiba gornjih i donjih sekutića, interincizalnog ugla, okluzije po Angle-u, incizalnog stepenika i incizalnog preklopa. Dobijeni rezultati obrađeni su statistički. Rezultati. Tokom terapije nastupile su statistički visokoznačajne promene u obe grupe: oralno naginjanje gornjih i vestibularno naginjanje donjih sekutića. Promene su bile izraženije u grupi bolesnika lečenih Herbst aparatom (p lt 0,001). Nagib gornjih sekutića promenjen je prosečno oko 9°, a donjih oko 7°. Odnos molara i incizalni razmak su u potpunosti korigovani na kraju lečenja u grupi lečenoj Herbst aparatom, dok su isti parametri u grupi sa aktivatorom bili nepotpuno korigovani. Nijedan od primenjenih aparata, na završetku lečenja, nije izazvao promene u vertikalnom preklopu sekutića. Zaključak. Poređenje terapijskih efekata Herbst aparata i aktivatora kod bolesnika uzrasta 14-21 godinu pokazalo je da je Herbst aparat efikasniji u korekciji dentoalveolarne malokluzije klase II odeljenja 1 nego aktivator