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Tinitus ili zujanje u uvu, je svesna percepcija zvuka uprkos izostanku spoljašnjeg zvučnog stimulusa. Koren reči tinitus potiče iz latinskog jezika (lat. tinnire- zvoniti, ), a skoro svaki čovek bar jednom u životu doživi tinitus. Trećina ima povremeno i kratkotrajno zujanje, dok 10% do 15% odraslih razvija hronicitet i tinitus postaje trajan, a često i nerešiv problem. Međutim, poslednjih godina tinitus se sve češće zapaža i u najranijem uzrastu, a broj studija koje ispituju tinitus kod dece i adolescenata neprekidno raste. Zbog neusaglašenog definisanja tinitusa, specifičnosti ispitivane populacije, kao i razlika u dizajnu studija koje ispituju prevalenciju tinitusa, učestalost tinitusa kod dece varira u širokom rasponu od 5% do 75%. Uprkos porastu naučnog interesovanja za tinitus, njegova etiologija je i dalje nedovoljno jasna. Faktori rizika koji dovode do ovog fenomena mogu biti socio-ekonomski, ekološki, bihejvioralni, hereditarni, dijetetski i drugi. Pacijenti sa tinitusom često somatizuju simptome, a tinitus može biti povezan i sa različitim psihološkim problemima, najčešće anksiozno- depresivne simptomatologije. Poznavanje faktora rizika i komorbiditeta povezanih sa tinitusom je važno zbog prevencije tinitusa i adekvatnog tretmana pacijenata. Cilj. Glavni cilj ovog istraživanja bio je da se ispitaju prevalencija tinitusa i faktori rizika za tinitus kod adolescenata u gradskoj sredini. Posebni ciljevi istraživanja bili su: da se utvrdi prevalencija tinitusa u beogradskoj adolescentskoj populaciji; da se ispita koji su činioci sredine značajni faktori rizika za tinitus adolescenata; da se utvrdi da li je tinitus kod roditelja faktor rizika za javljanje tinitusa kod adolescenata; da se utvrdi koje rizično ponašanje je faktor rizika za tinitus kod adolescenata; da se utvrdi da li je unos nekog nutrijenta povezan sa tinitusom kod adolescenata; da se ispita kakve su razlike u učestalosti i težini tinitusa u odnosu na uzrast i pol adolescenata; da se ispita kakva je povezanost između tinitusa, gubitka sluha, hiperakuzije i drugih otoloških oboljenja kao i bolesti ostalih organa i uzimanja specifičnih lekova kod adolescenata... Tinnitus, ear buzzing, is a conscious perception of sound despite the absence of an external sound stimulus. The root of the word tinnitus comes from the Latin language (lat. tinnire) which means "to ring", and almost every person experience tinnitus at least once in their life. One-third have occasional and short- term buzzing, while 10% to 15% of adults develop chronicity and tinnitus becomes a permanent and often unsolvable problem. However, tinnitus is increasingly being recorded at an early age, and the number of studies examining tinnitus in children and adolescents is ever-increasing. Due to the inconsistent definition of tinnitus, the characteristics of the examined population as well as the differences in the design of the studies examining the prevalence of tinnitus, the frequency of tinnitus in children varies in a wide range of 5% -75%. Despite the growing scientific interest in tinnitus, its etiology is still unclear. Risk factors for tinnitus can be socioeconomic, environmental, behavioral, hereditary, dietary, and others. Patients with tinnitus often somatize their symptoms, and tinnitus can also be associated with various psychological problems, most often within the anxiety-depressive symptomatology. Studying the risk factors and comorbidities associated with tinnitus is important for the prevention of tinnitus and adequate treatment of patients. Aim. The main aim of this study was to examine the prevalence of and risk factors for tinnitus among urban adolescents. The specific objectives of the study were: to determine the prevalence of tinnitus in a Belgrade adolescent population; to examine which environmental factors are significant for adolescent tinnitus; to determine whether parental tinnitus is a risk factor for the occurrence of tinnitus among their children; to determine which risky behavior is a risk factor for tinnitus in adolescents; to determine what nutrient is associated with tinnitus in adolescents; to examine the differences in the incidence and severity of adolescents' tinnitus in relation to age and sex; to examine the relationship between adolescents' tinnitus, hearing loss, hyperacusis and other otological diseases as well as other diseases and taking specific medications...

Introduction/Objective Knowledge and practical skills in medical waste (MW) management are of equal importance for medical and dental doctors. The first comparative study on the knowledge and skills in the field of MW management among Belgrade students was conducted with the goal of examining whether students of medicine and dentistry are equally familiar with this extremely important field. Methods a cross-sectional study included 558 students of the sixth year of studies (430 medical and 128 dental students) who completed an anonymous semi-structured questionnaire to determine attitudes and knowledge on MW management. Results the majority of medical and dental students had no training in MW management (79.5% and 74.6%, respectively). Dental students use protective equipment more frequently than medical students (94.5% vs. 42%, p lt 0.001). However, full vaccinal protection against hepatitis B is better among medical students compared to dental students (57.7% vs. 39.1%, p lt 0.001). Complete knowledge on postexposal prophylaxis is better among medical students compared to dental students (44.5% vs. 13.3%, p lt 0.001). However, dental students are more disciplined in reporting injuries (63.1% vs. 52.4%, p = 0.038). The students' knowledge on primary separation of infectious waste (93% vs. 77.8%, p lt 0.001) and used needles (80.3% vs. 70.4%, p = 0.007) is better among dental students compared to medical students' correct answers. Conclusion Dental students show better knowledge on MW management and are more disciplined in using personal infection protection compared to medical students. The students support continued training on MW management and investigations on this topic., Uvod/Cilj Znanje i praktične veštine upravljanja medicinskim otpadom su od posebnog značaja za doktore medicine i stomatologije. Komparativna studija o znanju i veštinama iz oblasti upravljanja medicinskim otpadom sprovedena je među beogradskim studentima prvi put, u cilju ispitivanja da li ovom izuzetno važnom oblašću studenti medicine i stomatologije vladaju podjednako dobro. Metode Ova studija preseka obuhvatila je 558 studenata šeste godine studija na Beogradskom univerzitetu (430 studenata medicine i 128 studenata stomatologije), koji su popunili anonimni upitnik o znanju i stavovima o upravljanju medicinskim otpadom. Rezultati Većina studenata stomatologije i medicine nisu imali nikakvu posebnu obuku iz upravljanja medicinskim otpadom (79,5% i 74,6%). Studenti stomatologije su češće koristili zaštitnu opremu (94,5% prema 42%, p lt 0,001). Vakcinalna zaštita od hepatitisa B je kompletnija među studentima medicine u odnosu na studente stomatologije (57,7% prema 39,1%, p lt 0,001). Znanje o profilaksi posle izloženosti bolja je među studentima medicine (44,5% prema 13,3%, p lt 0,001). Međutim, studenti stomatologije su ažurniji u pogledu prijavljivanja povreda na radnom mestu (63,1% prema 52,4%, p = 0,038). Znanje studenata o primarnoj separaciji infektivnog otpada i korišćenih igala je bolje među budućim stomatolozima (tačni odgovori 93% nasuprot 77,8%; p lt 0,001 i 80,3% prema 70,4%; p = 0,007). Zaključak Studenti stomatologije imaju bolje znanje o upravljanju medicinskim otpadom i disciplinovaniji su u pogledu korišćenja zaštitne opreme na radu u odnosu na studente medicine. Studenti podržavaju kontinuiranu edukaciju o upravljanju medicinskim otpadom i dalja istraživanja o ovoj temi.

The gypsy moth is a generalist insect pest with an extremely wide host range. Adaptive responses of digestive enzymes are important for the successful utilization of plant hosts that differ in the contents and ratios of constituent nutrients and allelochemicals. In the present study, we examined the responses of α-amylase, trypsin, and leucine aminopeptidase to two tree hosts (suitable oak, Quercus cerris, and unsuitable locust tree, Robinia pseudoacacia) in the fourth, fifth, and sixth instars of gypsy moth larvae originating from oak and locust tree forest populations (hereafter assigned as Quercus and Robinia populations, respectively). Gypsy moths from the Robinia forest had been adapting to this unsuitable host for more than 40 generations. To test for population-level host plant specialization, we applied a two-population × two-host experimental design. We compared the levels, developmental patterns, and plasticities of the activities of enzymes. The locust tree diet increased enzyme activity in the fourth instar and reduced activity in advanced instars of the Quercus larvae in comparison to the oak diet. These larvae also exhibited opposite developmental trajectories on the two hosts, i.e. activity increased on the oak diet and decreased on the locust tree diet with the progress of instar. Larvae of the Robinia population were characterized by reduced plasticity of enzyme activity and its developmental trajectories. In addition, elevated trypsin activity in response to an unsuitable host was observed in all instar larvae of the Robinia population, which demonstrated that Robinia larvae had an improved digestive performance than did Quercus larvae.

Temperatura i kvalitet hrane utiču na performansu larvi gubara, Lymantria dispar L. nezavisno ili u međusobnoj interakciji. Strategije preživljavanja larvi gubara u temperaturno kao i nutritivno heterogenoj sredini obuhvataju različite tipove reverzibilne i ireverzibilne fenotipske plastičnosti, koje preko uticaja na usvajanje i raspodelu resursa utiču na osobine životne istorije i rezistentnost prema ekstremnim uslovima životne sredine. U cilju ispitivanja efekata temperature i kvaliteta hrane, tj. sadržaja proteina i ugljenih hidrata u hrani na komponente adaptivne vrednosti, kao i ekspresiju genetičke varijabilnosti, larve gubara su izložene delovanju tri različite temperature (suboptimalna, optimalna i supraoptimalna) i 4 kombinacije hranljivog sastava dijete, koje su se međusobno razlikovale kako u ukupnom sadržaju proteina i ugljenih hidrata, tako i u njihovom međusobnom odnosu. U istim eksperimentalnim uslovima ispitivana je uloga procesa varenja, odnosno aktivnosti digestivnih enzima u usklađivanju odnosa i količine unetih nutienata sa potrebama organizma na različitim temperaturama. Takođe, ispitan je uticaj nutritivne vrednosti i balansiranosti hrane na senzitivnost gubara prema stresnim temperaturama. Nepovoljne temperature i nizak sadržaj proteina u hrani, kao i disbalans proteina u odnosu na ugljene hidrate, smanjuju performansu larvi gubara. Uticaji temperature i kvaliteta hrane na komponente adaptivne vrednosti: preživljavanje, trajanje razvića, masu i relativnu brzinu rasta, uglavnom su međusobno nezavisni. Pokazano je da povišena temperatura smanjuje preživljavanje i trajanje razvića larvi ali dovodi do povećanja relativne brzine rasta. Nutritivni sastav hrane nije uticao na preživljavanje, ali je nizak sadržaj proteina u hrani dovodio do produžavanja razvića, smanjenja mase i relativne brzine rasta larvi. Relativna brzina rasta larvi je bila manja i pri visokom sadržaju ugljenih hidrata u hrani, dok je smanjenje mase larvi na hrani sa niskim sadržajem proteina bilo veće ako je i sadržaj ugljenih hidrata bio nizak... Temperature and food quality affect the performance of gypsy moth larvae Lymantria dispar L. independently or in an interaction with each other. Survival strategies of gypsy moth larvae in temperature and nutritionally heterogeneous environments include various types of reversible and irreversible phenotypic plasticity, which due to the effect of uptake and distribution of resources affect the life-history traits and resistance to extreme environmental conditions. In order to investigate the direct and interactive effects of temperature and food quality on fitness components, as well as the expression of genetic variation, gypsy moth larvae were exposed to three different temperatures (suboptimal, optimal and supraoptimal) and 4 sets of nutrient composition of the diet, which differed in protein and carbohydrate content. Under the same experimental conditions, the role of digestion and digestive enzyme activity in adjusting nutrient quantity and ratio with organism needs at different temperatures was investigated. Also, it was investigated the effect of nutritional value of the food on sensitivity of gypsy moth larvae to stressful temperatures. An adverse temperature and low protein content in food, as well as an imbalance of protein compared to carbohydrates, reduced performance of gypsy moth larvae. Effects of temperature and food quality on fitness components - survival, developmental time, larval weight and relative growth rate were mainly independent. It has been shown that elevated temperature reduces survival and duration of development, but leads to an increase of the relative growth rate. Nutritional composition of food had no effect on survival, but the low protein content led to prolonged developmental time, reduced larval weight and relative growth rate of gypsy moth larvae. The relative growth rate of larvae was lower if carbohydrate content in food was high, while larval weight reduction was greater if protein content was low and the carbohydrate content was high...

Periodic fluctuations in density impose different selection pressures on populations of outbreaking Lepidoptera due to changes in their nutritional environment. The maternal effects hypothesis of insect outbreak predicts the transmission of this nutritional "information" to subsequent generations and alterations in offspring life-history traits. To test for these time-delayed effects of the parental generation, we compared life-history traits and their variation and covariation among laboratory-reared gypsy moths hatched from egg masses collected from low- and medium-density populations. Decreased individual performance was recorded in offspring from the medium-density population, indicating reduced egg provisioning under crowding conditions. Genetic variance and covariance were also shown to be sensitive to density of the parental generation. In gypsy moths from the medium-density population, quantitative genetic analysis revealed significantly higher broad-sense heritabilities for development duration traits and demonstrated a trade-off between development duration and body size. Lepidoptere sa eruptivnom populacionom dinamikom su izložene različitim selektivnim pritiscima tokom periodičnih fluktuacija brojnosti usled promena u nutritivnom kvalitetu njihove životne sredine. Hipoteza o ulozi materinskog efekta u pojavi prenamnoženja insekata predviđa prenos ove nutritivne "informacije" na sledeće generacije i promenu osobina životnog ciklusa kod potomaka. Da bismo testirali ovaj vremenski odložen uticaj parentalne generacije uporedili smo osobine životnog ciklusa, njihovu varijabilnost i međusobne korelacije između gubara gajenih u laboratoriji poreklom iz populacija niske i srednje brojnosti. Potomstvo poreklom iz populacije srednje brojnosti pokazalo je smanjenje individualne performanse što ukazuje na redukciju kvaliteta jaja sa porastom gustine populacije. Genetička varijansa i kovarijansa su takođe bile osetljive na gustinu roditeljske generacije. Kvantitativno-genetičkom analizom je dobijena veća heritabilnost u širem smislu za osobine trajanja razvića kao i uzajamno ograničenje između trajanja razvića i mase lutki gubara koje su poreklom iz populacije srednje brojnosti. Projekat ministarstva br. 143033

The effects of different temperatures (23°C and 8°C) on activity of corpora allata (CA) and dorsolateral (L1, L2) protocerebral neurosecretory neurons were investigated in Morimus funereus Mulsant (1863) larvae collected from a natural population during March. Activity of CA was revealed by monitoring of CA volume and cell number. Increase of CA volume after two day exposure to both temperatures was shown to be the result of increase in cell number. Activity of CA was higher at 23°C than 8°C. Activity of L1 and L2 neurosecretory neurons was inhibited at both temperatures. Neurosecretory neurons were more sensitive to temperature of 23°C than 8°C. It can be supposed that dorsolateral neurosecretory neurons synthesize neurohormones that affect CA activity, depending on environmental temperature. Ispitivan je uticaj različitih temperatura (23°C i 8°C) na aktivnost corpora allata (CA) i dorzolateralnih (L1 i L2) protocerebralnih neurosekretnih neurona kod larvi Morimus funereus Muls. (1863), sakupljenih iz prirode tokom meseca marta. Aktivnost CA je procenjivana praćenjem promena veličine CA i broja ćelija CA. Pokazano je da je povećanje veličine CA, nakon 2 dana izlaganja larvi obema temperaturama, rezultuje u povećanju broja ćelija. Aktivnost CA je veća na temperaturi od 230C, nego na 80C. Aktivnost L1 i L2 neurosekretnih neurona je bila inhibirana delovanjem obeju temperatura. Neurosekretni neuroni su osetljiviji na delovanje temperature od 230C, nego na 80C. Moglo bi se pretpostaviti da dorzolateralni neurosekretni neuroni sintetišu neurohormone koji utiču na aktivnost CA, u zavisnosti od temperature spoljašnje sredine. Projekat ministarstva br. 1615

The response of starved Morimus funereus larvae refed with an artificial diet (Galford, 1967) was examined in the present paper. Larvae were offered diets varying in protein quality (soya protein, casein, and gelatin). Refeeding with the Galford diet (G I) and two modifications of it in which soya protein was supplemented with casein (G II) or gelatin (G III) led to an increase of body mass. Different protein quality in the nutritive substrate influenced both the quantity and quality of midgut and brain proteins. U ovom radu je ispitivan uticaj veštačke dijete po Galfordu (Galford, 1967) i njene dve modifikacije različitog proteinskog sastava (protein soje, kazein želatin) na larve Morimus funereus nakon totalnog gladovanja. Telesna masa larvi se povećala nakon ishrane dijetom po Galfordu (G I), kao i njenim modifikacijama u kojima je protein soje zamenjen kazeinom (G II) odnosno želatinom (G III). Prisustvo proteina različitog kvaliteta u hranljivom supstratu utiče i na kvantitet i na kvalitet proteina srednjeg creva i mozga larvi ove vrste. null

Different proteolytic activities using natural and synthetic substrates were analyzed in the midgut of Cerambyx cerdo larvae. Significant leucyl-aminopeptidase and elastase-like activities, as well as some trypsin-like activities were detected. Korišćenjem prirodnih i sintetičkih supstrata analizirane su različite proteolitičke aktivnosti u srednjem crevu larve Cerambyx cerdo. Detektovane su značajne aktivnosti leucil-aminopeptidaze i elastazi sličnih enzima, kao i slabija aktivnost tripsinu sličnih enzima.

Different proteolytic activities using natural and synthetic substrates were analyzed in the midgut of Cerambyx cerdo larvae. Significant leucyl-aminopeptidase and elastase-like activities, as well as some trypsin-like activities were detected. Korišćenjem prirodnih i sintetičkih supstrata analizirane su različite proteolitičke aktivnosti u srednjem crevu larve Cerambyx cerdo. Detektovane su značajne aktivnosti leucil-aminopeptidaze i elastazi sličnih enzima, kao i slabija aktivnost tripsinu sličnih enzima. null