Investigation of the mutagenic effects of aluminium trioxide implants on embrions in experimental animals

Several diseases as well as trauma can affect the composition and integrity of periodontal tissues loading eventually to the destruction of connective tissue matrix and cells, loss of attachment and resorption of alveolar bone often followed by tooth loss. Replacement of the missing tooth could then be provided by endosseous dental implants healing in a form of osseo -or fibrosseal integration to the alveolar bone. Aluminium oxide ceramics, a form, of endosseous implant, allows osseointegration type of healing and has demonstrated excellent biocompatibility. However, potential aluminium toxicity has been implicated in the pathogenesis of a number of clinical disorders and for this reason we examined the reproductive and mutagenic effect of aluminium trioxide ceramic implant in experimental mice. 720 female and 45 fertile male BALB-cAn NCR mice were included in the study. 3 experimental groups of fertile male mice (15 for each group) were treated with an intraperitoneal injection of aluminium trioxide (I g/kg of body weight, group I), with ethyl-methane-sulphonate as a positive control (200 mg/kg, group II) and with Tween-80 (10 ing/kg as negative control, Group III). Each of the labeled male mice fertilized previously uncoupled female mice during 8 weeks (a pair per week) to facilitate appropriate pre-and post-meiotic conditions of spermatogenesis to occur. Female mice were sacrificed with cervical dislocation at day 13 after fertilization. Immediately upon sacrifice the uterus was removed and the number of alive and healthy, or alive but mutated and/or dead embryos was computed to determine the dominant lethal of mutagenic effects. Animals treated with aluminium trioxide demonstrated similar effects on the reproductive and mutagenic capacity as the negative control, whereas the animals treated as positive controls exhibited significantly reduced reproductive and mutagenic capacity. Collectively, we concluded that aluminium trioxide has a very low rate of embryonal mortality and mutagenicity in mice. This finding is in general agreement with the biocompatibility of aluminium trioxide (Aldovit) as an implant material

Praćenje nivoa alveolarne kosti u predelu zadržanih zuba kod pacijenata sa donjom totalnom supradentalnom protezom desetogodišnja longitudinalna studija

Aim: The aim of this study was to evaluate the effects of overdentures on the condition of alveolar bone around the remaining teeth over 10 years. Materials and Methods: After preparation of all the remaining abutment teeth in the lower jaw, overdentures were fabricated for 22 patients. The radiographs were made at the delivery stage, then 6 and 10 years after delivery. The radiographs were evaluated using the grid scale and the film holder made it possible to repeate x-ray procedure in every patient in the same manner. Results: We concluded that we achieved the maximum therapeutic effect. Conclusion: Good oral hygiene is the key of success with overdentures.Cilj: Cilj ove studije bio je da se izmere efekti supradentalnih proteza na stanje alveolarne kosti u predelu zadržanih zuba za vreme od 10 godina. Materijal i metod: Nakon pripreme svih zadržanih "patrljaka zuba" u donjoj vilici, načinjene su donje totalne supradentalne proteze za 22 pacijenta. Dentalne radiografije tih zuba su urađene na početku, pri predaji proteza, a zatim 6 i 10 godina nakon predaje. Dentalni rentgenski snimci upoređivani su uz pomoć žičane mrežice i držača rentgen filma koji su pripremljeni za svakog pacijenta i svaki zub idividualno čime je bila obezbeđena izrada identično pozicioniranih dentalnih radiografija u različitim vremenskim periodima. Rezultati: Dobijeni rezultati ove studije ukazuju da je postignut maksimalan terapeutski efekat u pacijenata sa malim brojem preostalih, parodontloški loših zuba. Zaključak: Dobra oralna higijena je ključ uspeha tretmana supradentalnim protezama

The Influence of seed storage on germination of tall fescue during after-ripening period

After the harvest of tall fescue seed dormancy is present, indicating the reduction of germination. In conventional storage conditions for seed storage, we investigated the influence of three different ways of packaging (paper bags, canvas bags and plastic bags) to change the germination of seeds immediately after harvest, after 30, 60 and 90 days. After 30 days seed dormancy is reduced by 1 to 3% and germination was increased by 2-3%, while the impact of packaging had no significant effect.The decreasing trend in seed dormancy and increased germination even after 60 days continued in the same percentages. After 90 days of storage the contents of dormant seed was reduced to 22-35% and germination was increased to 65-72%

Interdisciplinary crossover for rapid advancements - collaboration between medical and engineering scientists with the focus on Serbia

Over the past decades, development of engineering sciences has vastly contributed to advancements in medicine by production of numerous devices for diagnostics and treatment. In the middle of the 20th century, a new scientific field, biomedical engineering (BE), was established, which has developed into an extremely complex scientific discipline requiring a distinctive educational profile. Various study programs in BE have been established at universities around the world but also at several universities in Serbia. Also, intensive research in this field is performed at several scientific institutions in Serbia. In the present paper, short summaries of the research results of several groups of engineers and medical doctors are presented as an illustration of the wide field of BE research and possibilities of its application in diagnosis and therapy of various diseases

Effect of storage time and type of packaging on seed quality of tall fescue

After harvesting, the seed dormancy of grasses occurs. During the maturing period, seed dormancy is slowly reduced, and seed germination reaches the maximum values of use. Germination decreases during longer storage. The levels of seed dormancy and germination prevention determine the complex of physiological and biochemical processes in the seeds, which vary depending on genetic background, environment during maturation, and even the position of seeds on the plant. The goal is to maintain, as long as possible, the maximum germination after seed ripening. However, aging and germination reduction are processes which largely depend of storage conditions and seed packaging. The three tested seed lots of tall fescue were kept in paper, textile and polyethylene (PVC) containers during 10, 16, 24, 28, 34 and 40 months. The dormancy, germination energy, and total germination were examined. The seeds stored in PVC containers required a shorter period of time in order to release from dormancy and achieve maximum germination (16 months, 43% germination). After 40 months, there was a significant decrease in germination (80%). In some seed lots, the germination dropped to 77%, which is the required minimum for marketing authorization (The Official Gazette of the Republic of Serbia, No. 47/48). In the case of the seeds kept in paper containers, the maximum germination (89% and 90%) was obtained after 22 months. The same seed germination was obtained after 40 months of storage

Interdisciplinary crossover for rapid advancements: Collaboration between medical and engineering scientists with the focus on Serbia

Napretku medicine su poslednjih decenija veoma mnogo doprineli pronalasci iz različitih oblasti inženjerstva. Polovinom dvadesetog veka uspostavlja se nova naučna oblast, biomedicinsko inženjerstvo (BI), koje se do sada razvilo u veoma složenu naučnu disciplinu koja je zahtevala i poseban obrazovni profil. Na univerzitetima širom sveta, kao i na nekoliko univerziteta u Srbiji ustanovljeni su različiti programi iz oblasti biomedicinskog inženjerstva. Takođe, u nekoliko naučnih institucija u Srbiji sprovode se intenzivna istraživanja u ovoj oblasti. U ovom radu prikazani su rezultati istraživanja nekoliko grupa naučnika iz oblasti inženjerstva i medicine sa ciljem da se ilustruje koliko je široko polje istraživanja u oblasti biomedicinskog inženjerstva i kakve su mogućnosti njihove primene u dijagnostici i lečenju različitih bolesti.Over the past decades, development of engineering sciences has vastly contributed to advancements in medicine by production of numerous devices for diagnostics and treatment. In the middle of the 20th century, a new scientific field, biomedical engineering (BE), was established, which has developed into an extremely complex scientific discipline requiring a distinctive educational profile. Various study programs in BE have been established at universities around the world but also at several universities in Serbia. Also, intensive research in this field is performed at several scientific institutions in Serbia. In the present paper, short summaries of the research results of several groups of engineers and medical doctors are presented as an illustration of the wide field of BE research and possibilities of its application in diagnosis and therapy of various diseases

Prinos semena crvenog vijuka (Festuca rubra L.) i korelaciona međuzavisnost sa komponentama prinosa i kvalitetom semena

The paper presents the results of two years of research conducted in eastern Serbia (2007-2008). Tests were conducted with domestic varieties K-14, which was developed at the Institute for Forage Crops, Krusevac. At two different densities B1 (the inter-row distance of 12.5 cm and 15 kg ha-1 seed) and B2 (25 cm row spacing and 7.5 kg ha-1 seed) following components of yield were observed: plant height (cm), number of generative stems, inflorescence length (cm), number of branches in umbel; seed yield (kg ha-1) The following parameters of seed quality were: 1000 seed weight (g), germination energy (%), germination of seeds (%). Interdependence of the traits was determined by simple correlation coefficients (r). The highest seed yield was recorded in density B2. Variability of seed yield was high (CV = 49.9%), because influence of year and plant density. Seed yield achieved the strongest positive correlation (p ≤ 0.01), with generative stems (r=0.994). Also strong dependence was found between plant height and number of generative stems (r=0.977).Rad prikazuje rezultate dvogodišnjih ispitivanja sprovedenih u istočnoj Srbiji (2007­ 2008). Ispitivanja su izvedena sa domaćom sortom K-14, koja je stvorena u Institutu za krmno bilje, Kruševac. Na dve različite gustine: B1 (setva na međuredno rastojanje 12,5 cm i sa 15 kg ha-1 semena) i B2 (25 cm međuredno rastojanje i 7,5 kg ha-1 semena) praćene su sledeće komponente prinosa: visina stabljike (cm), broj generativnih stabljika, dužina cvasti (cm), broj grana u cvasti, prinos semena (kg ha-1). Praćeni su sledeći parametri kvaliteta semena: masa 1000 semena (g), energija klijanja (%), ukupna klijavost semena (%). Međuzavisnost ispitivanih osobina utvrđena je prostim koeficijentima korelacije (r). Veći prinos semena ostvaren je sa gustinom B2. Varijabilnost prinosa pod uticajem godine i gustine, bila je visoka (CV =49,9%). Prinos semena ostvario je najjaču pozitivu korelativnu međuzavisnost (p≤0,05) sa generativnim stabljikama (r=0,994). Takođe jaka zavisnost utvrđena je između visine stabljika i broja generativnih stabljika (r=0,977)

Desiccation, postharvest maturity and seed aging of tall oat-grass

The objectives of this work were to determine whether and at which seed physiological maturity stage the diquat desiccant affects the tall oat-grass (Arrhenatherum elatius) seed quality and yield, as well as the proper storage period between harvest and sowing. Diquat desiccation was evaluated in applications during milk or dough seed maturation stages. Seeds conventionally produced and stored under traditional storage conditions were used for the analyses. Seed samples were drawn every 30(th) day after harvest (DAH). After the 240(th) DAH, samples were drawn every 90(th) day up the to 690(th) DAH. The highest yield were obtained by desiccation applied at the beginning of the seed dough stage, with a satisfactory seed quality. Both final germination and seedling growth parameters achieved their maximum values between 180(th) and 240(th) DAH. Oat-grass seeds preserved satisfactory level of final germination (75%) up to 420(th) DAH. The application of diquat desiccant at the beginning of seed dough maturity stage can be a good solution for seed production of tall oat-grass. Early spring is the best sowing period for freshly harvested seeds of tall oat-grass regarding germination and seedling growth

Drying of meadow fescue seeds of different moisture contents: Changes in dormancy and germination

In the past few years in Europe grass seed production declines. This tendency is especially pronounced in meadow fescue. Seed shedding and therefore yield losses are the problem in seed production. This can be reduced if seed of higher moisture contents is harvested. The impacts of drying temperatures of 70, 60, 50, 40 and 22 degrees C on changes in dormancy and germination of seed harvested with moisture contents of 45, 35 and 25% were observed in the present study. The analysis was done immediately after seed drying, then three months later and eight months later. Seeds with the moisture content of 45% that were dried at 70 degrees C were not dormant at all after harvest, but seeds were damaged, which resulted in reduced germination. Drying temperatures of 40 degrees C and 50 degrees C resulted in maximum germination of seed harvested with 45% moisture after three months. After eight months the best germination of all seeds was obtained at 22 degrees C and 40 degrees C. The seed ageing test confirmed faster deterioration of seeds harvested with higher moisture contents. Seed harvested with 25% moisture and dried at 22 degrees C is the most suitable seed for longer storage

Seed germination and seedling vigour of Italian ryegrass, cocksfoot and timothy following harvest and storage

During post-harvest maturation, different species vary in the length of dormancy breaking or germination increases. Seed dormancy and slow seedling development often limit establishment of forage grass stands. Seed germination and seedling vigour of Italian ryegrass (Lolium italicum A. Braun, Synonym Lolium multiflorum L.), cocksfoot (Dactylis glomerata L.) and timothy (Phleum pretense L.) were observed after harvest and storage. After harvest in June, seeds were stored under standard storage conditions and sampled every 30 days after harvest (DAH), up to 270 DAH, and then every 60 days up to 990 DAH. At each date, seeds were tested for final germination percentage and for seedling vigour traits. Timothy seeds had a maximum germination (88%) and the best seedlings vigour at 90 DAH, which implies that early autumn (September-October) is the best sowing period for freshly harvested seeds of timothy. Timothy seed germination was poor from 270 DAH (73%). The best germination and vigour of Italian ryegrass and cocksfoot seedlings were between 270 and 330 DAH, which equates to spring sowing time (March-April) in the succeeding year. Cocksfoot and Italian ryegrass seeds maintained satisfactory germination levels up to 630 DAH (81%) and 810 DAH (81%), respectively. The data can serve for the determination of a proper storage duration management between harvest and sowing of the tested species under ambient conditions of south-eastern Europe