29 research outputs found
āA matter of healthā: Evaluation of health habits in pupils in Primary School in Serbia
We interviewed more than 400 primary school pupils from 5th to the 8th grade (aged 11 to 14 years) from the primary school in Belgrade (Serbia) about their habits concerning nutrition, beverage consumption, and time spend in front of a computer, tablet, playing games on consoles, or using a mobile phone. According to the study, a high percentage of students showed a well-established habit of eating breakfast. Also, the overall water consumption prevailed in all grades, since the school ensures students access to safe and free drinking water, as a healthy alternative to consumption of sugar-sweetened beverages. However, we found increasing food consumption from bakery and consumption of carbonated drinks both in boys and girls from senior grades (7th and 8th). Also, they spent considerably more time with a computer, tablet, or mobile phone than the pupils from lower grades. About one-third of all surveyed students have been watching television or using a computer more than 3 hours during the day. We found a significant increase of BMI, as an indicator of the increasing risk of weight gain and obesity both in boys and girls in senior grades. In the current curriculum of Biology, the topic of human health is studied in the 7th grade, but presented results show that one-year education in health topics is not sufficient. It suggests the necessity of introducing the topic of health in all grades of elementary school, starting from the lowest age
OdreÄivanje etanola u dijetetskim suplementima tipa sirupa
Dietary supplements are intended to supplement normal nutrition and they are concentrated sources of vitamins, minerals and other substances with nutritional and physiological effects. Because of large use of dietary supplements, which often contain ethanol, we have to educate health workers, as well as consumers in this area, and hope that the use of dietary supplements will become safe, controlled and rational. Ethanol is used for extraction, and it is also important as a stabilizer in a significant number of dietary products in the form of syrup. Because of that, a lot of dietary products contain ethanol, and often it is not declared. One more problem is the fact that users who read the declaration cannot conclude that ethanol is present in these products. Also, some of these syrups can be ordered through the internet without information of percentage of ethanol, which is worrying. Besides that, some syrup contains concentrations of ethanol in the amount that is the same as is in spirit drinks. We used liquid chromatography with a refractometer detector and carbohydrate column, temperature 90ā¦C, for the detection of ethanol in a dietary supplements syrup-type between 2007 to 2016. Then we ordered concentration of ethanol by external standard method. Content of ethanol was from lt 0,05% to 28,35%. We analyzed 76 syrups and 67% of them did not have ethanol on a declaration. 8% of syrups with ethanol declaration did not have the same amount of ethanol as remarked on the declaration. Also, 66% of all tested syrups had alcohol higher than 1,2% [12]. Syrups are traditionally used in our country, and often used in combination with some drugs, and that can lead to different adverse reaction.Dijetetski suplementi su namenjeni dopuni normalne ishrane i predstavljaju koncentrovane izvore vitamina, minerala i drugih supstanci sa hranljivim i fizioloÅ”kim efektom. Zbog velike upotrebe dijetetskih preparata, koji Äesto sadrže etanol, moraju se edukovati zdravstveni radnici, kao i potroÅ”aÄi koji ih konzumiraju, kako bi upotreba dijetetskih suplemenata postala sigurna, kontrolisana i racionalna. Etanol se koristi za ekstrakcije, i takodje je važan kao stabilizator u velikom broju dijetetskih suplemenata u obliku sirupa. Zbog toga, veliki broj dijetetskih proizvoda sadrži etanol, a Äesto se deÅ”ava da nije ni deklarisan. JoÅ” jedan problem je i Äinjenica da potroÅ”aÄi koji Äitaju deklaraciju ovih proizvoda ne mogu da zakljuÄe da je etanol prisutan. TakoÄe, neki od ovih sirupa se mogu naruÄiti putem interneta, bez informacije o sadržaju etanola, Å”to je zabrinjavajuÄe. Osim toga, neki sirupi sadrže istu koncentraciju etanola, kao Å”to je to i u alkoholnim piÄima. Koristili smo teÄnu hromatografiju, refraktometrijski detektor, ugljeno-hidratnu kolonu, temperaturu 90Ā°C, za detekciju etanola u dijetetskim suplementima, tipa sirupa, tokom 2007 do 2016. godine. Zatim smo odreÄivali koncentraciju etanola eksternom standardnom metodom. Koncentracija etanola se kretala u opsegu od lt 0,05% do 28,35%. Od 76 analiziranih sirupa 67% nije imalo deklarisan etanol. 8% od sirupa sa deklarisanim etanolom, nije imalo istu koncentraciju kao Å”to je deklarisano. Takodje, 66% od svih analiziranih sirupa je imalo alkohol veÄi od 1,2% [12]. Sirupi se tradicionalno koriste u naÅ”oj zemlji, a Äesto i u kombinaciji sa drugim lekovima, Å”to može izazvati razliÄite neželjene reakcije
Cuticular chemoprofile of the fruit fly Drosophila Subobscura (Diptera, drosophilidae)
In insects, cuticular hydrocarbon (CHC) profile is involved in many important biological functions and may vary in different conditions. Among fruit fly species, Drosophila subobscura is one of the most frequently used in genetic, ecological and evolutionary research, because of its rich chromosomal polymorphism, specific behavioral repertoires and habitat preferences. In this work, we identified and quantified cuticular chemoprofile of D. subobscura. Using gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC-MS), 25 chemical compounds were found in males and 23 compounds were found in females. Further, ANOVA confirmed significant sexual dimorphism in cuticular chemoprofile amounts. Knowledge of cuticular chemistry could contribute to further research in D. subobscura, starting from behavioral, up to ecological, since this species is recognized as an important model system for the study and monitoring of global climate changes. Ā© 2018, Pakistan Agricultural Scientists Forum. All rights reserved
Cuticular chemoprofile of the fruit fly drosophila subobscura (diptera, drosophilidae)
In insects, cuticular hydrocarbon (CHC) profile is involved in many important biological functions and may vary in different conditions. Among fruit fly species, Drosophila subobscura is one of the most frequently used in genetic, ecological and evolutionary research, because of its rich chromosomal polymorphism, specific behavioral repertoires and habitat preferences. In this work, we identified and quantified cuticular chemoprofile of D. subobscura. Using gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC-MS), 25 chemical compounds were found in males and 23 compounds were found in females. Further, ANOVA confirmed significant sexual dimorphism in cuticular chemoprofile amounts. Knowledge of cuticular chemistry could contribute to further research in D. subobscura, starting from behavioral, up to ecological, since this species is recognized as an important model system for the study and monitoring of global climate changes
Note on the fauna of Drosophila (Diptera: Drosophilidae) and the first record of Opomyza florum (Diptera: Opomyzidae) from mt. GoÄ, Serbia
Fauna of Drosophilidae in Serbia has been studied for 40 years. This paper presents the results of faunistic research conducted on Mt. GoÄ in June 2011 in two forests (beech and oak), which are significantly different in the type of vegetation and microclimatic factors. In the oak forest eight species of Drosophila were registered, while in the beech forest only five species were recorded. A relatively small number of species recorded is, among other things, the result of extremely bad weather conditions during the collection attempts. An interesting non-drosophilid fly was also found in the sample - Opomyza florum Fabricius, 1794 (Diptera: Opomyzidae). Since there is very little data concerning the distribution of O. florum in Serbia, this paper is an invitation to entomologists to further study this species, including faunistical, ecological and behavioral aspects, keeping in mind its potential economic impact.Fauna Drosophilidae se u Srbiji izuÄava veÄ 40 godina. U ovom radu su prikazani rezultati faunistiÄkog istraživanja sprovedenog na GoÄu u junu 2011. godine, u dve Å”ume (bukovoj i hrastovoj), koje se znatno razlikuju u tipu vegetacije i mikroklimatskim faktorima. U hrastovoj Å”umi je registrovano 8 vrsta Drosophila, a u bukovoj 5 vrsta. Relativno mali broj registrovanih vrsta je, izmeÄu ostalog, posledica ekstremno loÅ”ih vremenskih uslova tokom sakupljanja muÅ”ica. U uzorku sakupljenih muva utvrÄeno je i prisustvo žute žitne muve, Opomyza florum Fabricius 1794 (Diptera: Opomyzidae). ImajuÄi u vidu da postoji vrlo malo podataka koji se tiÄu distribucije O. florum u Srbiji, ovaj rad je i poziv entomolozima u smislu daljeg izuÄavanja ove vrste, sa faunistiÄkog, ekoloÅ”kog i aspekta ponaÅ”anja, s obzirom na njen potencijalni ekonomski znaÄaj.Projekat ministarstva br. 17301
Aspartate or arginine? Validated redox state X-ray structures elucidate mechanistic subtleties of FeIVā=āO formation in bacterial dye-decolorizing peroxidases
Structure determination of proteins and enzymes by X-ray crystallography remains the most widely used approach to complement functional and mechanistic studies. Capturing the structures of intact redox states in metalloenzymes is critical for assigning the chemistry carried out by the metal in the catalytic cycle. Unfortunately, X-rays interact with protein crystals to generate solvated photoelectrons that can reduce redox active metals and hence change the coordination geometry and the coupled protein structure. Approaches to mitigate such site-specific radiation damage continue to be developed, but nevertheless application of such approaches to metalloenzymes in combination with mechanistic studies are often overlooked. In this review, we summarize our recent structural and kinetic studies on a set of three heme peroxidases found in the bacterium Streptomyces lividans that each belong to the dye decolourizing peroxidase (DyP) superfamily. Kinetically, each of these DyPs has a distinct reactivity with hydrogen peroxide. Through a combination of low dose synchrotron X-ray crystallography and zero dose serial femtosecond X-ray crystallography using an X-ray free electron laser (XFEL), high-resolution structures with unambiguous redox state assignment of the ferric and ferryl (FeIVā=āO) heme species have been obtained. Experiments using stopped-flow kinetics, solvent-isotope exchange and site-directed mutagenesis with this set of redox state validated DyP structures have provided the first comprehensive kinetic and structural framework for how DyPs can modulate their distal heme pocket Asp/Arg dyad to use either the Asp or the Arg to facilitate proton transfer and rate enhancement of peroxide heterolysis
Cuticular chemoprofile of the fruit fly Drosophila Subobscura (Diptera, drosophilidae)
In insects, cuticular hydrocarbon (CHC) profile is involved in many important biological functions and may vary in different conditions. Among fruit fly species, Drosophila subobscura is one of the most frequently used in genetic, ecological and evolutionary research, because of its rich chromosomal polymorphism, specific behavioral repertoires and habitat preferences. In this work, we identified and quantified cuticular chemoprofile of D. subobscura. Using gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC-MS), 25 chemical compounds were found in males and 23 compounds were found in females. Further, ANOVA confirmed significant sexual dimorphism in cuticular chemoprofile amounts. Knowledge of cuticular chemistry could contribute to further research in D. subobscura, starting from behavioral, up to ecological, since this species is recognized as an important model system for the study and monitoring of global climate changes. Ā© 2018, Pakistan Agricultural Scientists Forum. All rights reserved
Mating behavior as an indicator of quality of Drosophila subobscura males?
According to current theoretical predictions, any deleterious mutations that reduce nonsexual fitness may have a negative influence on mating success. This means that sexual selection may remove deleterious mutations from the populations. Males of good genetic quality should be more successful in mating, compared to the males of lower genetic quality. As mating success is a condition dependent trait, large fractions of the genome may be a target of sexual selection and many behavioral traits are likely to be condition dependent. We manipulated the genetic quality of Drosophila subobscura males by inducing mutations with ionizing radiation and observed the effects of the obtained heterozygous mutations on male mating behavior: courtship occurrence, courtship latency, mating occurrence, latency to mating and duration of mating. We found possible effects of mutations. Females mated more frequently with male progeny of nonirradiated males and that these males courted females faster compared to the male progeny of irradiated males. Our findings indicate a possible important role of sexual selection in purging deleterious mutations
Chemical Ecology of Cave-Dwelling Millipedes: Defensive Secretions of the Typhloiulini (Diplopoda, Julida, Julidae)
Cave animals live under highly constant ecological conditions and in permanent darkness, and many evolutionary adaptations of cave-dwellers have been triggered by their specific environment. A similar "cave effect" leading to pronounced chemical interactions under such conditions may be assumed, but the chemoecology of troglobionts is mostly unknown. We investigated the defensive chemistry of a largely cave-dwelling julid group, the controversial tribe "Typhloiulini", and we included some cave-dwelling and some endogean representatives. While chemical defense in juliform diplopods is known to be highly uniform, and mainly based on methyl- and methoxy-substituted benzoquinones, the defensive secretions of typhloiulines contained ethyl-benzoquinones and related compounds. Interestingly, ethyl-benzoquinones were found in some, but not all cave-dwelling typhloiulines, and some non-cave dwellers also contained these compounds. On the other hand, ethyl-benzoquinones were not detected in troglobiont nor in endogean typhloiuline outgroups. In order to explain the taxonomic pattern of ethyl-benzoquinone occurrence, and to unravel whether a cave-effect triggered ethyl-benzoquinone evolution, we classed the "Typhloiulini" investigated here within a phylogenetic framework of julid taxa, and traced the evolutionary history of ethyl-benzoquinones in typhloiulines in relation to cave-dwelling. The results indicated a cave-independent evolution of ethyl-substituted benzoquinones, indicating the absence of a "cave effect" on the secretions of troglobiont Typhloiulini. Ethyl-benzoquinones probably evolved early in an epi- or endogean ancestor of a clade including several, but not all Typhloiulus (basically comprising a taxonomic entity known as "Typhloiulus sensu stricto") and Serboiulus. Ethyl-benzoquinones are proposed as novel and valuable chemical characters for julid systematics.Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3085
Serial Femtosecond Crystallography Reveals the Role of Water in the One- or Two-Electron Redox Chemistry of Compound i in the Catalytic Cycle of the B-Type Dye-Decolorizing Peroxidase DtpB
Controlling the reactivity of high-valent Fe(IV)-O catalytic intermediates, Compounds I and II, generated in heme enzymes upon reaction with dioxygen or hydrogen peroxide, is important for function. It has been hypothesized that the presence (wet) or absence (dry) of distal heme pocket water molecules can influence whether Compound I undergoes sequential one-electron additions or a concerted two-electron reduction. To test this hypothesis, we investigate the role of water in the heme distal pocket of a dye-decolorizing peroxidase utilizing a combination of serial femtosecond crystallography and rapid kinetic studies. In a dry distal heme site, Compound I reduction proceeds through a mechanism in which Compound II concentration is low. This reaction shows a strong deuterium isotope effect, indicating that reduction is coupled to proton uptake. The resulting protonated Compound II (Fe(IV)-OH) rapidly reduces to the ferric state, giving the appearance of a two-electron transfer process. In a wet site, reduction of Compound I is faster, has no deuterium effect, and yields highly populated Compound II, which is subsequently reduced to the ferric form. This work provides a definitive experimental test of the hypothesis advanced in the literature that relates sequential or concerted electron transfer to Compound I in wet or dry distal heme sites