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Relationship between lower extremity strength, local endurance and dynamic knee valgus angle in elite female handball players
No full textNajozbiljnije ozljede u rukometu su ozljede koljena, posebno ozljeda prednjeg križnog ligamenta (PKL). Žene su pod većim rizikom od muškaraca za ozljedu PKL-a, a učestalost ozljede najviša je kod vrhunskih sportašica. Neuromišićni faktori koji bi mogli biti odgovorni za povećani rizik od ozljede PKL-a kod sportašica kao i njihova moguća interakcija još uvijek nisu dovoljno istraženi. Glavni cilj ovog istraživanja bio je utvrditi povezanost eksplozivne jakosti, lokalne izdržljivosti, odnosa jakosti mišića te maksimalne jakosti mišića ekstenzora i fleksora koljena s dinamičkim valgus kutom koljena prilikom funkcionalnih testova skoka kod vrhunskih rukometašica. Drugi cilj je utvrditi postoje li razlike u dobivenim rezultatima s obzirom na dominantnost noge po kriteriju jakosti i preciznosti te po kriteriju odrazne noge. Uzorak ispitanica sačinjavalo je 30 vrhunskih sportašica, rukometašica reprezentativnog ranga (dob x̅ = 25.40 ± 3.55; visina tijela x̅ = 176.86 ± 5.73; težina tijela x̅ = 71.57 ± 7.76). Uvjet sudjelovanja u istraživanju bio je da sportašice nisu imale ozljedu ili sindrom prenaprezanja donjih ekstremiteta najmanje 8 mjeseci prije mjerenja, te da u trenutku mjerenja nisu osjećale bol u donjim ekstremitetima. Podatci o mišićnoj jakosti ekstenzora i fleksora koljena prikupljani su s pomoću izokinetičkog sustava Biodex System 3 (Biodex Medical Systems, Shirley, N.Y., USA), dok su kinematički i kinetički podatci iz funkcionalnih testova skoka prikupljani s pomoću sustava kojeg je sačinjavalo 8 kamera s frekvencijom snimanja od 200 Hz (BTS Smart-d, BTS Bioengineering, Padova, Italy), te dvije platforme sila dimenzija 600 mm x 400 mm (Type 9286 A, Kistler Instrumente AG, Winterthur, Switzerland). Izokinetički test je izvođen na 3 kutne brzine u koncentrično/koncentričnom modalitetu rada - 5 ponavljanja na 60°/sek, 10 ponavljanja na 180°/sek i 15 ponavljanja na 300°/sek. Protokol funkcionalnog mjerenja skoka proveden je u biomehaničkom laboratoriju, a provedena je kinematsko-kinetička analiza dvije vrste vertikalnog skoka - skoka s pripremom i skoka s povišenja. Dominantnost noge određivana je prema kriterijima preciznosti, jakosti te po kriteriju odrazne noge.
Za sve varijable izračunati su centralni i disperzivni parametri. Normalitet distribucije varijabli testiran je Shapiro – Wilkovim testom. Za varijable koje su se koristile u testovima razlike, uz testiranje normalnosti distribucije, Levenovim testom izračunata je i homogenost varijance, a sve radi odabira parametrijske ili neparametrijske statističke metode. Povezanost između praćenih varijabli izražena je Spearmanovim koeficijentima korelacije. Jednosmjernom analizom varijance
utvrđene su razlike između aritmetičkih sredina 3 grupe (s obzirom na kriterij dominantnosti noge: kriterij jakosti, odrazne noge ili preciznosti) u pokazateljima maksimalne i eksplozivne jakosti, odnosa jakosti, lokalne izdržljivosti mišića nogu te dinamičkog valgus kuta koljena. Doprinos pojedinih varijabli objašnjenju nastanka dinamičkog valgus kuta koljena dominantne noge ispitao se serijom jednostavnih i složenih linearnih regresijskih analiza. Pri tome je kriterijska varijabla bio dinamički valgus kut koljena u fazi doskoka, dok su prediktorske varijable bili pokazatelji maksimalne i eksplozivne jakosti, odnosa jakosti mišića prednje i stražnje strane natkoljenice te lokalne izdržljivosti mišića nogu. Razina statističke značajnosti bila je postavljena na p<0,05.
Rezultati istraživanja ukazali su na statistički značajnu negativnu povezanost (p0.05) vršne vrijednosti snage prilikom doskoka dobivene funkcionalnim testom skoka s pripremom s dinamičkim valgus kutom koljena dobivenim funkcionalnim testom skoka s pripremom kod kriterija odabira dominantnosti noge po preciznosti.
S druge strane, rezultati analize razlika u praćenim varijablama ukazuju da ne postoji razlika u dobivenim rezultatima s obzirom na korišteni kriterij dominantnosti noge.
Zaključno, rezultati ukazuju na povezanost eksplozivne i maksimalne jakosti nogu s dinamičkim valgus kutom koljena, te da bilateralni skokovi i izolirani izokinetički test mišića ekstenzora i fleksora koljena nije idealan za detekciju dominantnosti ekstremiteta, odnosno mogućeg utjecaja dominantnosti na izvedbu. Dodatno učinjenom regresijskom analizom ustanovljena je potencijalna prediktivna vrijednost eksplozivne jakosti mišića ekstenzora koljena na dinamički valgus kut koljena. Osim navedenog, na temelju rezultata predložene su i modifikacije u formiranju preventivnih programa kao i izrade protokola mjerenja u svrhu prevencije i rehabilitacije ozlijede PKL-aThe most serious injuries in handball are knee injuries, especially anterior cruciate ligament (ACL) injuries. The dynamic nature of this sport, characterized by movements like accelerations, decelerations, sprints, changes of direction, jumps, throws, pushes, and pulls, performed at maximum speed and often in conditions of instability classifies handball as a sport with an increased risk of injury compared to other team and individual sports. Women are 4-6 times at higher risk than men for ACL injury, and the frequency of injury is highest in elite athletes. The nature of ACL injury is multifactorial, but literature evidence indicates that impaired biomechanics and neuromuscular control of the lower extremities and trunk are the main factors of a higher injury rate in female athletes. Neuromuscular factors that could be responsible for the increased risk of ACL injury in female athletes, as well as their possible interaction, have not yet been sufficiently investigated. The first aim of this research was to determine the relationship between explosive strength, local muscle endurance, H/Q ratio, and maximal strength of the extensor and flexor muscles of the knee with the dynamic valgus angle of the knee during functional jump tests in elite handball players. The second aim was to determine whether there are differences in the obtained results regarding leg dominance according to the criterion of strength, precision, and takeoff leg. The sample consisted of 30 elite female handball players, members of national teams (age x̅ = 25.40 ± 3.55; body height x̅= 176.86 ± 5.73; body weight x̅ = 71.57 ± 7.76). The inclusion criteria for participation in the research were that the athletes did not have another injury or overuse syndrome of the lower extremities at least 8 months before the measurement, with no lower extremities pain experience at the time of the measurement. Data on muscle strength of knee extensors and flexors were collected using the isokinetic system Biodex System 3 (Biodex Medical Systems, Shirley, N.Y., USA), while kinematic and kinetic data from functional jump tests were collected using a system consisting of 8 cameras with a recording frequency of 200 Hz (BTS Smart-d, BTS Bioengineering, Padova, Italy), and two force platforms (Type 9286A, Kistler Instrumente AG, Winterthur, Switzerland). The isokinetic test was performed at 3 angular velocities in concentric/concentric mode - 5 repetitions at 60°/sec, 10 repetitions at 180°/sec and 15 repetitions at 300°/sec. The functional jump measurement protocol was performed in the biomechanical laboratory, and the kinematic-kinetic analysis of two types of vertical jump,
countermovement jump and drop jump was analyzed. Each athlete performed 3 successful attempts at countermovement jump and drop jump. Leg dominance was determined according to the criteria of precision, strength, and takeoff leg. For the criterion of precision, the test was to determine the leg with which a person kicks the ball, while for the strength criterion the measured maximum moment of the knee extensor muscles was measured at angular speed of 60 st./sec. expressed in newton meters (Nm). Single leg countermovement jump height was used as the criterion for selecting the take-off leg. Central and dispersive parameters were calculated for all variables. The normality of the distribution of variables was tested with the Shapiro-Wilk test. For the variables used in the difference tests, in addition to testing the normality of the distribution, the homogeneity of the variance was calculated using Levene's test, all for the purpose of choosing a parametric or non-parametric statistical method. The relationship between monitored variables was expressed by Spearman's correlation coefficients. One-way analysis of variance revealed differences between the means of the 3 groups (with respect to leg dominance criteria: precision, strength or take-off leg criteria) as indicators of explosive and maximum strength, H/Q ratio, local leg muscle endurance and dynamic knee valgus angle. The contribution of individual variables to the explanation of the dynamic knee valgus angle of the dominant leg was examined by a series of simple and complex linear regression analyses. Here, the criterion variable was the dynamic valgus angle of the knee in the landing phase, while the predictor variables were indicators of explosive and maximum strength, H/Q ratio and the local muscle endurance. The level of statistical significance was set at p < 0.05. The results of the research indicated a statistically significant negative correlation (p < 0.05) between the variable of explosive strength Time to peak torque and of the maximum dynamic valgus angle of the knee in drop jump in all 3 criteria of leg dominance. A significant negative correlation (p < 0.05) was found between explosive strength variables - flight time measured during countermovement jump and the maximum dynamic knee valgus angle during the countermovement jump in the dominance selection criteria by precision, and between take-off velocity variable that was measured during countermovement jump and the maximum dynamic knee valgus angle during the countermovement jump in the dominance selection criteria by precision. Furthermore, a statistically significant negative correlation (p < 0.05) was found
between the Peak torque value of knee flexors obtained during isokinetic testing at an angular speed of 60°/sec and the maximum dynamic valgus angle of the knee during drop jump in the selection criteria of take-off leg. Also, it was determined that there is a statistically significant negative correlation (p 0.05) of the Peak power value during the take-off phase of countermovement jump with the maximum dynamic valgus angle of the knee during countermovement jump in the selection criterion of leg dominance by precision. The results indicate that there is no difference in the obtained results regarding the criterion for selecting the dominant leg. An additional regression analysis confirmed the potential predictive value of the explosive strength of the knee extensor muscles on the dynamic knee valgus angle. This research has contributed to a better understanding of the complex nature of ACL injury. From the practical point, the development of maximal strength of the knee flexor muscles, reactivity of the knee extensor and flexor muscles with an emphasis on fast contractions may contribute to improving movement control. Also, the development of explosive strength through plyometric content can contribute to better neuromuscular control of the lower extremities, and consequently to a lower rate of ACL injuries. The results also indicate the importance of the knee flexor muscles as dynamic joint stabilizers, and the role of knee extensors in controlling knee movements in the frontal plane during dynamic activities. Ultimately, the results indicate the connection of explosive and maximal leg strength with the dynamic knee valgus angle, and that bilateral jumps and isolated isokinetic tests of knee extensor and flexor muscles are not ideal for detecting limb dominance, i.e. the possible influence of dominance on performance. An explanation of lateral dominance may be that this phenomenon is potentially related to mechanisms involving complex processes in the central nervous system. In addition to the above, based on the results, modifications were proposed in the creation of preventive programs as well as the development of measurement protocols for the purpose of ACL prevention and rehabilitation
Rekonstrukcija oceanografskih polja pomoću strojnog učenja
No full textSoftware sensor augmentation utilises various machine learning algorithms to increase the range, resolution, or absolute accuracy of measurements. Within the domain of oceanographic remote sensing missing data represent a frequent issue. Although there exist numerous methods and models for estimating the missing data based on statistics, the issue remains open. Recent research have shown that a specific architecture of neural networks can be utilised to reconstruct satellite-derive sear surface temperature based on pattern recognition. However, this model has not yet been applied to other oceanographic data. This thesis examines the application of machine learning model to widen the sensors coverage with the aim of estimating the missing data. The reconstruction accuracy of this model is compared to the accuracy of other reconstruction methods. The general validity of reconstructed data is shown via encaptured underlying processes. Additional accuracy boost is achieved via a locally calibrated model of satellite measurements.Proširenje osjetilnosti senzora podrazumijeva poboljšanje sposobnosti senzora – bilo da je riječ o prostornom dosegu, rezoluciji uzorkovanja ili točnosti mjerenja. Unutar domene daljinskih mjerena za oceanografske svrhe učestali problem predstavljaju podaci koji nedostaju. Iako već postoje brojne metoda i modeli za njihovu procjenu na temelju statistike, problem nije trajno riješen. Posljednjih godina primjenjuje se specifična arhitektura neuronskih mreža za procjenu podataka koji nedostaju kod satelitski mjerene površinske temperature mora na temelju prepoznavanja uzoraka. Međutim, ovakav model do sada nije primijenjen nad ostalim oceanografskim podacima. U okviru predložene teme planira se primjena modela strojnog učenja u svrhu povećanja dosega senzora s ciljem procjene podataka koji nedostaju. Točnost rekonstrukcije modela uspoređena je s točnošću drugih rekonstrukcijskih modela. Opća valjanost rekonstruiranih podataka prikazana je kroz opisane temeljne procese. Dodatno povećanje točnosti i preciznosti postiže se izradom lokalno kalibriranih satelitskih mjernih algoritama
ITGA8 and VANGL2 as prognostic markers of congenital anomalies of the kidney and urinary tract in a human and a mouse
No full textUVOD: Urođene anomalije bubrega i mokraćnog trakta (CAKUT) čine skup strukturnih i funkcionalnih anomalija koje nastaju tijekom razvoja bubrega i mokraćnog trakta u embrionalnom razdoblju. S učestalošću od jednog slučaja na 500 novorođenčadi, ove anomalije spadaju među najčešće urođene poremećaje. CAKUT uključuje širok raspon nepravilnosti koje se mogu pojaviti izolirano ili kao dio sindromskih poremećaja, često dovodeći do teških oštećenja bubrega i mokraćnog trakta. Unatoč ranoj dijagnozi, značaj CAKUT-a ne ograničava se samo na neonatalno razdoblje jer predstavlja vodeći uzrok kroničnog bubrežnog zatajenja u djece. Bubrežna displazija i hipoplazija odgovorne su za približno 20% ovih slučajeva, dok nasljedne bolesti poput policistične bolesti bubrega u odrasloj dobi uzrokuju 10% kroničnih zatajenja bubrega. CILJ ISTRAŽIVANJA: Cilj ovog istraživanja je analizom imunofluorescencije utvrditi prostornu i vremensku raspodjelu proteina ITGA8 i VANGL2 u bubrezima zdravih, normalnih te CAKUT ljudskih fetalnih uzoraka. Također, istraživanje ima za cilj ispitati utjecaj utišavanja gena Dab1 na izražaj proteina Itga8 i Vangl2 u embrionalnim i postnatalnim uzorcima miša. MATERIJALI I METODE: U ovom istraživanju analizirani su obrasci izražaja kandidata gena za CAKUT, integrina alfa-8 (ITGA8) i Van Gogh-like 2 (VANGL2), primjenom imunohistokemije i imunofluorescencije u ljudskim fetalnim tkivima zdravih i CAKUT bubrega, kao i u modelu yotari (yot) miševa s mutacijom u genu Dab1. REZULTATI: Rezultati su pokazali da izražaj Itga8 i Vangl2 varira pod uvjetima CAKUT-a te je značajno povišena u embrionalnim bubrezima yotari (yot) miševa u usporedbi s divljim tipom (wt), dok se u postnatalnim bubrezima nisu uočile značajne promjene. Prostorno, Itga8 je najizraženiji u metanefričkom mezodermu i bubrežnim vezikulama/nezrelim glomerulima, dok je Vangl2 pokazao izraženu prisutnost u metanefričkom mezodermu, vezikulama, nezrelim glomerulima te sabirnim kanalićima. Uz to, otkriveno je da u ljudskim uzorcima VANGL2 zadržava stalan izražaj tijekom fetalnog sazrijevanja, dok izražaj ITGA8 varira. U usporedbi sa zdravim bubrezima (CTRL), ITGA8 je slabije izražen u bubrezima s udvostručenim ureterom (DK) i displastičnim bubrezima (DYS), dok je VANGL2 značajno izražen u displastičnim (DYS), a slabije u hipoplastičnim bubrezima (HYP). ZAKLJUČAK: Ovi rezultati predlažu da poremećaji izražaja ITGA8 i VANGL2, uzrokovani genetskim čimbenicima poput mutacije gena Dab1, pridonose razvojnim defektima bubrega povezanima s CAKUT fenotipovima. Identifikacija ovih proteina kao potencijalnih prognostičkih pokazatelja i terapijskih ciljeva za CAKUT otvara mogućnosti za daljnje istraživanje molekularnih mehanizama koji leže u pozadini diferencijalnog izražaja ITGA8 i VANGL2.INTRODUCTION: Congenital anomalies of the kidney and urinary tract (CAKUT) represent a group of structural and functional abnormalities that arise during the development of the kidneys and urinary tract in the embryonic period. With an incidence of one case per 500 newborns, these anomalies rank among the most common congenital disorders. CAKUT encompasses a broad spectrum of defects that can occur as isolated anomalies or as part of syndromic disorders, often leading to significant damage to the kidneys and urinary tract. Despite early diagnosis, the importance of CAKUT extends beyond the neonatal period, as it remains a leading cause of chronic kidney failure in children. Renal dysplasia and hypoplasia are responsible for approximately 20% of these cases, while hereditary diseases such as polycystic kidney disease account for 10% of chronic kidney failure in adults. AIM OF THE STUDY: This study uses immunofluorescence analysis to determine the spatial and temporal distribution of ITGA8 and VANGL2 proteins in the kidneys of healthy, normal, and CAKUT human fetal samples. Additionally, it aims to investigate the impact of Dab1 gene silencing on the expression of Itga8 and Vangl2 proteins in embryonic and postnatal mouse samples. MATERIALS AND METHODS: In this study, we analyzed the expression patterns of CAKUT candidate genes, integrin alpha-8 (ITGA8) and Van Gogh-like 2 (VANGL2), using immunohistochemistry and immunofluorescence in human fetal tissues of healthy and CAKUT-affected kidneys, and in the yotari (yot) mouse model carrying a Dab1 gene mutation. RESULTS: The results showed that the expression of Itga8 and Vangl2 varies under CAKUT conditions and is significantly elevated in embryonic kidneys of yotari (yot) mice compared to wild-type (wt) mice. At the same time, no significant differences were observed in postnatal kidneys. Spatially, Itga8 exhibited the strongest expression in the metanephric mesenchyme and renal vesicles/immature glomeruli, whereas Vangl2 demonstrated pronounced expression in the metanephric mesenchyme, vesicles, immature glomeruli, and collecting ducts. Additionally, VANGL2 maintained a constant expression in human samples during fetal maturation, while ITGA8 expression varied. Compared to healthy kidneys (CTRL), ITGA8 was poorly expressed in duplex kidneys (DK) and dysplastic kidneys (DYS). At the same time, VANGL2 showed significant expression in dysplastic kidneys (DYS) and lower expression in hypoplastic kidneys (HYP). CONCLUSION: These findings suggest that disruptions in ITGA8 and VANGL2 expression, caused by genetic factors such as Dab1 gene mutations, contribute to kidney developmental defects associated with CAKUT phenotypes. Identifying these proteins as potential prognostic markers and therapeutic targets for CAKUT opens opportunities for further research into the molecular mechanisms underlying the differential expression of ITGA8 and VANGL2
Recovery evaluation in patients after whiplash injury of the neck after physical therapy using shear wave elastography and neck disability index six months after a traffic accident
No full textUvod: U procjeni i praćenju osoba nakon trzajne ozljede vrata koriste se subjektivne mjere od kojih se kao pouzdan i najčešće korišten izdvaja NDI. S obzirom da do ozljede najčešće dolazi u prometnim nesrećama, česta su potraživanja odšteta. Nedostatak objektivnih mjera stvara prostor za simuliranje, a često se rade dijagnostičke pretrage koje nemaju prognostičku vrijednost niti se pomoću njih može procijeniti oporavak. Osnova liječenja su terapijske vježbe koje su se uz edukaciju jedine pokazale učinkovite u smanjenju onesposobljenosti. Liječenje nije optimalno tako da veliki postotak osoba nakon ozljede pati od kronične boli i onesposobljenosti. U prvom dijelu ove doktorske disertacije cilj je bio ispitati mogućnost korištenja elastografije trapeznog mišića posmičnim valom kao objektivne metode u inicijalnoj evaluaciji i praćenju oporavka šest mjeseci nakon trzajne ozljede vrata. U drugom dijelu cilj je bio ispitati mogućnost poboljšanja oporavka utjecajem na adherenciju u provođenju terapijskih vježbi dnevnim podsjećanjem na vježbanje putem mobilne aplikacije. Metode: Prvo smo prospektivnim opažajnim istraživanjem pratili osobe nakon trzajne ozljede vrata kroz šest mjeseci. Svi ispitanici su proveli standardnu fizikalnu terapiju (2 ciklusa fizikalne terapije, 10 terapija po ciklusu, 5x tjedno s pauzom od 3 tjedna između terapija). Elastografija posmičnim valom i NDI rezultat napravljeni su inicijalno i nakon šest mjeseci. Elastografija je učinjena od strane dvoje radiologa. Napravljen je prediktivni model statusa oporavka šest mjeseci nakon ozljede te usporedba elastografije i NDI rezultata šest mjeseci od ozljede sa subjektivnim osjećajem oporavka bolesnika. U drugom istraživanju napravili smo sekundardnu analizu podataka koje su uključivale elastografiju trapeznog mišića osoba nakon trzajne ozljede i onih iz opće populacije. U trećem istraživanju randomizirano-kontroliranim pokusom smo ispitivali kako kod osoba koje su pretrpile trzajnu ozljedu vrata i provele standardnu fizikalnu terapiju svakodnevno podsjećanje na provođenje vježbi utječe na adherenciju i oporavak mjeren NDI-om šest mjeseci od ozljede u odnosu na one koji su nakon fizikalne terapije dobili pisane i usmene preporuke o nastavku provođenja vježbi kod kuće. Rezultati: Prvo istraživanje: 24 osobe su napravile inicijalna mjerenja, 22 osobe su završile istraživanje. Elastografska mjerenja su pokazala odličnu pouzdanost unutar (ICC 0.75-0.94) i između ispitivača (ICC 0.78-0.88). Nakon šest mjeseci umanjila se napetost trapeznog mišića, ali statistički značajno samo za drugog radiologa (Δ8.63 kPa; p=0.07 vs. Δ10.1 kPa; p=0.04). Nakon šest mjeseci elastografske vrijednosti nisu se razlikovale s obzirom na status oporavka (55.6±9.7 vs. 57±15.8, Δ1.45; p=0.82) dok su osobe koje su prijavljivale potpuni oporavak imale značajno niži NDI rezultat u odnosu na neoporavljene ili parcijalno oporavljene (Δ22.98; p<0.001). Pojedinačno se, poznavajući relativnu promjenu NDI-a najtočnije (73.9%) i sa niskim Akaike informacijskim kriterijom (AIC=39.2) može klasificirati osobu u neku od kategorija percipiranog oporavka. Uvrštavajući zajedno NDI rezultat i napetost trapeznog mišića šest mjeseci od ozljede točnost klasifikacije se povećala na 77.3% sa smanjenjem moguće greške (AIC=32.8). Drugo istraživanje: Analizirana je elastografija trapeznog mišića kod 99 osoba nakon trzajne ozljede i 75 osoba iz opće populacije. Prosječna napetost trapeznog mišića nakon ozljede bila je 82.24±21.11 kPa dok je za one iz opće populacije bila 57.47±13.82 kPa. Granična vrijednost elastografije od 75.8 kPa pokazala je 77% točnost u kategoriziranju osobe u jednu od skupina. Treće istraživanje: Analizirano je 29 osoba iz intervencijske i 30 iz kontrolne skupine. Šest mjeseci od ozljede uspoređujući skupine, intervencijska skupina pokazala je značajnije adheriranje (median [IQR]) u provođenju terapijskih vježbi kod kuće (3 [2–4] vs. 2 [2–4]; p=0.005) te poboljšanu HRQoL (20 [6–36] vs. 15 [9–23]; p=0.038). U intervencijskoj skupini je za razliku od kontrolne opaženo značajno smanjenje osoba koje katastrofiziraju zbog boli u dvije mjerene točke (31%; p=0.01). Nije nađena razlika u NDI rezultatu, intenzitetu boli te percipiranom oporavku. Zaključak: U prva dva istraživanja pokazali smo kako je elastografija trapeznog mišića posmičnim valom objektivna metoda koja se može koristiti u inicijalnom probiru osoba nakon trzajne ozljede vrata, ali se ne može koristiti u prognoziranju niti praćenju oporavka šest mjeseci od ozljede. U te svrhe zlatni standard ostaje NDI. Povećanje adherencije na terapijske vježbe nakon trzajne ozljede vrata može se postići korištenjem dnevnih podsjetnika putem mobilne aplikacije. S obzirom da učestalije vježbanje nije rezultiralo boljim oporavkom šest mjeseci nakon ozljede, potrebno je individualizirati pristup u liječenju te modificirati vježbe u osoba rizičnih za razvoj kronične onesposobljenosti.Background: In evaluation and follow-up after a whiplash injury of the neck, subjective measurements are used, among which the most reliable and the most used is NDI. Considering injury usually happens in car accidents, there are often requests for financial compensation. Lack of objective measurements leaves room for malingering, and diagnostic tests that are without prognostic value and can’t predict recovery are often performed. The basic treatment consists of physical exercise and educational measures which are the only ones proven to be effective in reducing disability. The treatment is not yet optimized, and a large percentage of patients suffer from chronic pain and disability. The aim of the first part of this doctoral dissertation was to evaluate the possibility of using shear wave elastography as an objective method in initial evaluation and follow-up six months after a whiplash injury of the neck. In the second part, we aimed to evaluate the possibility of improving outcomes by increasing adherence to exercise using daily reminders sent via a mobile application. Methods: An observational study of patients after whiplash injury over a period of six months was conducted. All subjects did standard physical therapy (2 cycles of 10 therapy sessions, 5x a week with a break of 3 weeks in between cycles). Shear wave elastography and NDI scores were obtained initially and after six months. Elastography was performed by two radiologists. A predictive model of recovery status six months after injury was made, along with a comparison of elastography and NDI score six months after injury with subjectively perceived recovery. In the second study, a secondary analysis of data was made comparing the elastography of trapezius muscle in patients six months after whiplash injury and those from the general population. The third study was a randomized-controlled study that evaluated the effect of daily mobile application reminders to exercise on adherence and recovery measured by NDI six months after physical therapy. Patients with whiplash injury of the neck had standard physical therapy and were then given either oral and written instructions on how to exercise at home or a mobile application. The two groups were compared. Results: First study: 24 people made initial measurements, and 22 finished follow-up. Elastography measurements showed excellent intraobserver (ICC 0.75-0.94) and interobserver (ICC 0.78-0.88) reliability. After six months, there was a decrease in trapezius muscle stiffness, though statistically significant only in the second radiologist (Δ8.63 kPa; p=0.07 vs. Δ10.1 kPa; p=0.04). Also, elastography values after six months did not differ according to recovery status (55.6±9.7 vs. 57±15.8, Δ1.45; p=0.82), while patients who reported full recovery had significantly lower NDI scores compared to the partially recovered or not recovered group (Δ22.98; p<0.001). Knowing relative change in NDI, an individual person can be categorized by recovery status most precisely (73.9%) and with low Akaike information criteria (AIC=39.2). Second study: Elastography of the trapezius muscle in 99 patients after whiplash injury and 75 people from the general population was analyzed. Average trapezius muscle stiffness after injury was 82.24±21.11 kPa, and in the general population was 57.47±13.82 kPa. Cut off value of 75.8 kPa showed 77% accuracy in categorizing a person into one of the groups. Third study: 29 people from the intervention group and 30 people from the control group were analyzed. When comparing groups six months after injury, the intervention group showed significantly higher adherence (median [IQR]) to a home exercise program (3 [2–4] vs. 2 [2–4]; p=0.005) with improved HRQoL (20 [6–36]vs. 15 [9–23]; p=0.038). In the intervention group, unlike the control group, there was asignificant drop in pain catastrophizing between the two time points (31%; p=0.01). There was no difference in NDI score, pain intensity, or perceived recovery. Conclusion: The first two studies show shear wave elastography of the trapezius muscle to be an objective method that can be used in the initial screening of people after a whiplash injury of the neck but can’t be used in follow-up and predicting recovery six months after injury, where NDI remains the golden standard. Adherence to physical exercise after a whiplash injury of the neck can be increased using daily reminders via mobile application. Considering that more frequent exercise did not lead to better recovery six months after injury, there is a need for a more personalized approach, and modifications to exercise should be made for patients with a higher risk for chronic disability
SIRTUIN 3 PROTEIN IN SEX-SPECIFIC MAINTENANCE OF ENERGY HOMEOSTASIS DURING AGING
No full textStarenje je složen biološki proces, a promjene do kojih pritom dolazi počinju na staničnoj razini tedovode do narušene energetske homeostaze. Važnu ulogu u očuvanju energetske homeostaze ima mitohondrijska deacetilaza Sirtuin 3 (Sirt3), čija je funkcija deacetilacija proteina uključenih u metaboličke puteve za proizvodnju energije. Cilj istraživanja bio je ispitati ulogu Sirt3 u promjenama u energetskoj homeostazi ovisnima o spolu tijekom starenja u modelu miševa in vivo i modelu mišjih embrionalnih fibroblasta (MEF) in vitro. U istraživanju na modelu in vitro, korišten je etopozid za umjetno izazivanje promjena povezanih sa starenjem. U uvjetima homeostaze vidljiv je utjecaj nedostatka Sirt3, dok spolne razlike postaju vidljive nakon tretmana etopozidom: ženska knock-out (KO) stanična linija posebno je osjetljiva na stres izazvan tretmanom, potencijalno zbog nemogućnosti nadoknade gubitka Sirt3. U modelu in vivo primijećene su samo spolne razlike: ženke imaju viši energetski status i usmjeravaju metabolizam prema oksidaciji masnih kiselina za dobivanje energije.Aging is a complex biological process that begins at the cellular level, disrupting energy
homeostasis. The mitochondrial deacetylase Sirtuin 3 (Sirt3) plays a crucial role in maintaining
this balance by deacetylating proteins involved in metabolic pathways for energy production.
This research aimed to examine the role of Sirt3 in sex-dependent changes in energy
homeostasis during aging, using an in vivo mouse model and an in vitro mouse embryonic
fibroblasts (MEF) model. In the in vitro model, etoposide was used to induce age-related
changes. Under control conditions, Sirt3 deficiency effects were evident, while etoposide
treatment revealed sex-specific differences: female knock-out (KO) MEFs showed particular
sensitivity, likely due to an inability to compensate for Sirt3 loss. In the in vivo model, only
sex-specific differences were observed, with females generally displaying a higher energy
status and a metabolic shift towards fatty acid oxidation for energy production
The influence of the method of closing the surgical wound during carpal tunnel decompression on functional, neurological and aesthetic outcomes and on quality of life: a prospective randomized clinical study
No full textCiljevi: Sindrom karpalnog tunela predstavlja najčešću perifernu neuropatiju koja se javlja uslijed pritiska na medijalni živac unutar karpalnog tunela. Učinak tkivnih adheziva kao materijala za zatvaranje rana nakon otvorene operacije dekompresije karpalnog tunela nije do sada istraživan. Cilj ovog istraživanja bio je procijeniti rane i kasne kliničke ishode usporedbom dvaju metoda zatvaranja postoperacijske rane nakon otvorene operacije karpalnog tunela kod ispitanika koji su randomizirani za korištenje ljepila za tkivo ili šavova. Metodologija: Ova randomizirana jednocentrična jednostruko slijepa kontrolirana prospektivna studija započeta u travnju 2022. godine obuhvatila je 100 ispitanika (70 žena) u dobi od 61,56 ± 12,03 godina, nasumično raspoređenih na zatvaranje rane šavovima (n = 50) ili za zatvaranje rana tkivnim ljepilom (n = 50) Glubran Tiss 2®. Ishodi su procijenjeni postoperativno tijekom perioda praćenja u intervalima od 2, 6 i 12 tjedana. Procjena ožiljka provedena je korištenjem ljestvice za procjenu ožiljaka bolesnika i promatrača (POSAS) i kozmetičke vizualne analogne ljestvice (VAS). Za ocjenu boli upotrijebljena je verbalna numerička skala (VNRS). Zabilježene su rane i kasne postoperacijske komplikacije. Prije operacije i šest mjeseci nakon operacije procijenjeni su snaga ruke, elektroneurografske karakteristike medijalnog živca i Bostonski upitnik karpalnog tunela. Ishodi kvalitete života i kvalitete sna su procijenjeni tijekom 12-mjesečnog postoperativnog praćenja. Za procjenu poremećaja spavanja korišteni su Pittsburgh Sleep Quality Index (PQSI) i Insomnia Severity Scale (ISI), a za procjenu kvalitete života povezane sa zdravljem ukupni SF-36 (36-Item Short Form Survey). Rezultati: Postojale su značajne razlike između zatvaranja rane ljepilom i zatvaranja rane šavom u intervalima od dva tjedna i šest tjedana nakon operacije na ljestvicama POSAS i kozmetički VAS (bolji estetski učinak tehnikom zatvaranja rane ljepilom), s manje postoperativne boli u istim intervalima. S intervalom od 12 tjedana, razlike u rezultatima nisu bile statistički značajne. Nije bilo značajnih razlika u ranim ili kasnim postoperacijskim komplikacijama. Značajne razlike između tehnika zatvaranja rana na temelju ljepila i šavova utvrđene su u šestomjesečnoj postoperativnoj snazi stiska šake (25,06 ± 6,69 naspram 21,41 ± 5,62 kg, P = 0,002), postoperativnoj senzornoj amplitudi (10,08 ± 5,50 naspram 7,54 ± 5,41 mV, P = 0,012) i postoperativnoj senzornoj brzini medijalnog živca (42,22 ± 11,04 naspram 35,23 ± 16,40 m/s, P = 0,008). U skupini s tkivnim ljepilom, značajno je više ispitanika postiglo postoperativnu senzornu brzinu veću od 45 m/s (47,9% naspram 22,0%, P = 0,006), postoperativnu distalnu senzornu latenciju manju od 3,5 ms (89,6% naspram 84,0%, P = 0,304) i postoperativnu motoričku latenciju manju od 4,2 ms (60,42% prema 38,00%, P = 0,022). Ljestvice PQSI, ISI i SF-36 nisu pokazale statistički značajne razlike među skupinama tijekom praćenja, osim u rezultatu ISI dva tjedna nakon operacije (9,40 ± 1,18 u skupini koja je koristila tkivno ljepilo naspram 9,96 ± 1,09 u skupini sa šavovima, P = 0,008). Rezultati PQSI, ISI i SF-36 za sve ispitanike i skupine kontinuirano su se poboljšavali u svim vremenskim intervalima praćenja nakon operacije. Ukupan rezultat SF-36 povećao se 12 mjeseci nakon operacije (49,84 ± 5,85 naspram 82,46 ± 5,68, P < 0,001). Zaključak: Tkivna ljepila na bazi cijanoakrilata mogu imati prednost u usporedbi s konvencionalnim tehnikama šivanja kože za zatvaranje kirurških rana nakon otvorene dekompresije karpalnog tunela u pogledu bržeg poboljšanja estetskih učinaka i postoperacijske boli, s očekivanim boljim učincima na oporavak srednjeg živca i poboljšanje snage ruke, što u konačnici dovodi do poboljšanja kvalitete sna, smanjenja težine nesanice i poboljšanja ukupne kvalitete života. Zatvaranje rane nakon operacije dekompresije karpalnog tunela može se učinkovito i sigurno izvršiti tkivnim ljepilom na bazi cijanoakrilata, uz očekivano poboljšanje ranih i kasnih kliničkih ishoda.Aims: Compression of the medial nerve in the carpal tunnel results in the most prevalent peripheral neuropathy, known as carpal tunnel syndrome. The effect of tissue adhesives as a wound closure material after open carpal tunnel decompression surgery has not been investigated. The aim of the study was to evaluate early and late clinical outcomes by comparing two modalities of postoperative wound closure after open carpal tunnel surgery in subjects randomized to either tissue adhesive or sutures. Methods: A randomized, single-center, single-blind, controlled prospective study started in April 2022 included 100 subjects (70 women) aged 61.56 ± 12.03 years, randomly assigned to wound closure with sutures (n = 50) or to closure wound with tissue glue (n = 50) Glubran Tiss 2®. During the follow-up phase, postoperative outcomes were assessed at 2, 6, and 12 week intervals. Cosmetic VAS (Visual Analog Scale) and POSAS (Patient and Observer Scar Evaluation Scale) were used for scar assessment. Pain was measured using the VNRS (Verbal Number Rating Scale). Early and late postoperative complications were recorded. Hand strength, electroneurographic characteristics of the median nerve and the Boston Carpal Tunnel Questionnaire were assessed before surgery and six months after surgery. Quality of life and sleep quality outcomes were assessed during the 12-month postoperative follow-up. The Pittsburgh Sleep Quality Index (PQSI) and Insomnia Severity Scale (ISI) were used to assess sleep disorders, and the overall SF-36 (36-Item Short Form Survey) was used to assess health- related quality of life. Results: There were significant differences between wound closure with glue and wound closure with suture at 2-week and 6-week postoperative intervals on the POSAS and cosmetic VAS scales (better aesthetic effect with the technique of wound closure with glue), with less postoperative pain at the same intervals. After 12 weeks, the differences were not statistically significant. There were no significant differences in early or late postoperative complications. Significant differences between wound closure techniques based on glue and sutures were found in 6-month postoperative hand grip strength (25.06 ± 6.69 vs. 21.41 ± 5.62 kg, P = 0.002), postoperative sensory amplitude (10.08 ± 5.50 vs. 7.54 ± 5.41 mV, P = 0.012) and postoperative sensory velocity of the median nerve (42.22 ± 11.04 vs. 35.23 ± 16.40 m/s, P = 0.008). In the tissue adhesive group, significantly more subjects achieved postoperative sensory velocity greater than 45 m/s (47.9% vs. 22.0%, P = 0.006), postoperative distal sensory latency less than 3.5 ms (89.6 % vs. 84.0%, P = 0.304) and postoperative motor latency less than 4.2 ms (60.42% vs. 38.00%, P = 0.022). With the exception of the ISI score two weeks following surgery (9.40 ± 1.18 in the tissue adhesive group vs. 9.96 ± 1.09 in the with sutures, P = 0.008), there was no statistically significant difference in the PQSI, ISI, or SF-36 scores across groups during follow-up. At every postoperative follow-up interval, the PQSI, ISI, and SF-36 scores for every subject and group showed steady improvement. A year following surgery, the SF-36 total score increased (49.84 ± 5.85 vs. 82.46 ± 5.68, P < 0.001). Conclusion: Cyanoacrylate-based tissue adhesives may have an advantage compared to conventional skin suturing techniques for surgical wound closure after open carpal tunnel decompression in better of aesthetic effects and less postoperative pain with expected better effects on median nerve recovery and improvement of hand strength, with consecutively improvement in the quality of sleep, reduction of insomnia severity and improvement in the overall quality of life. Wound closure after carpal tunnel decompression surgery can be effectively and safely performed with cyanoacrylate-based tissue adhesive with expected improvement in early and late clinical outcomes
Phenotypic and genetic characteristic of the exterior and fertility traits of Banija spotted pig
No full textBanijska šara (BŠ) izvorna je pasmina svinja uvrštena na popis izvornih i zaštićenih
pasmina i sojeva 2018. od kada se nalazi u programu konzervacije. Navedeno, kao i
činjenica da se radi o relativno maloj populaciji, poznavanje njenih fenotipskih i genetskih
karakteristika neophodno je za provedbu programa konzervacije, kao i provođenje ciljanih
sparivanja kako bi se zadržale pasminska obilježja i genetska raznolikost unutar populacije.
Veličina legla jedno je od najvažnijih proizvodnih svojstava u svinjogojskoj proizvodnji, a
identifikacija kandidat gena za veličinu legla doprinosi povećanju reproduktivne
učinkovitosti. Cilj je ovog istraživanja utvrditi morfometrijske karakteristike i obilježja
vanjštine, reproduktivne pokazatelje i polimorfizam ESR1 i RBP4 gena te njihov utjecaj na
svojstvo veličine legla kao i genetsku raznolikost i strukturu populacije BŠ svinje. Analizom
morfometrijskih svojstava i obilježja vanjštine 50 odraslih reproduktivno aktivnih jedinki
utvrđeno je da BŠ spada u pasmine svinja srednje velikog tjelesnog okvira s visinom do
grebena između 72 i 77 cm i tjelesnom masom oko 160 kg. Pasminu karakterizira
prekrivenost tijela s pretežito sivobijelom bojom dlake i nepravilnim crnim šarama koje
zauzimaju više od 50 % površine tijela te djelomična pigmentiranost sluznica i papaka.
Analizom ukupno 184 legla BŠ svinje utvrđena je prosječna veličina legla od 8,5
ukupnooprasene (UO), odnosno 7,5 živooprasene (ŽO) prasadi što je za 2,0 praseta više
u odnosu na crnu slavonsku svinju i 3,1 praseta više u odnosu na turopoljsku svinju. Na 25
krmača BŠ svinje provedena je genotipizacija ESR1 i RBP4 gena. Frekvencija genotipova
za oba istraživana marker gena (ESR1 i RBP4) u populaciji BŠ svinje ne pokazuju značajno
odstupanje od Hardy-Weibergove ravnoteže. Za ESR1 gen karakterističan je visoki udio
alela A (0,78), odnosno visoki udio homozigotnih jedinki AA genotipa (0,60). Kod RBP4
gena prevladava prisutnost alela B (0,60) te jedinke BB genotipa (0,44). Polimorfizam ESR1
gena nije imao značajan utjecaj na pokazatelje plodnosti kod BŠ dok je taj utjecaj prisutan
kod prvopraskinja u odnosu na RBP4 gen. Svinje BŠ pokazuju veliku genetsku raznolikost
unutar populacije mjerenu pomoću pokazatelja opažene (Ho) i očekivane (He)
heterozigotnosti (0,6349 i 0,6566), broja alela po lokusu (NA; 7,1875), sadržaja polimorfnih
informacija (PIC; 0,6123) i Fis - koeficijenta inbridinga (0,03317), te se genetski razlikuju od
sličnih i geografski bliskih populacija svinja uključujući i one s kojima dijele zajedničke pretke
(crna slavonska svinja) ili koje su imale utjecaja na njeno stvaranje (turopoljska svinja).In 2018, the Banija spotted pig breed (Banijska šara, BS) was added to the list of native and
protected pig breeds and strains. This, along with the fact that the population is small in
comparison, confirms that information about its phenotypic and genetic traits is required for
the implementation of targeted pairings and conservation programs aimed at preserving
genetic diversity and breed characteristics within the population. Identifying potential genes
for litter size increases the efficiency of reproduction, making litter size one of the most
significant production characteristics in pig production. The extended goal of this research
was to determine morphometric characteristics, external features, reproductive indicators,
and the polymorphism of the ESR1 and RBP4 genes, along with their impact on litter size,
genetic diversity, and population structure of BS pigs. Body mass and morphometric
properties (wither’s height, height at the sacrum, and root of the tail; seven measurements
on the trunk and four on the extremities) were determined on fifty adult and reproductively
active individuals (38 sows and 12 boars), aged 14 to 44 months, in various reproductive
stages. For morphometric measurements, Lydtin’s rod, a measuring tape, and a protractor
were utilised. A livestock scale (TehnoNet) was used to determine body mass. In order to
compare the reproductive indicators of the Banija spotted pig with those of two other
autochthonous breeds (Black Slavonian and Turopolje pigs), an analysis was conducted on
184 litters of Banija spotted pigs, 1174 litters of Turoplje pigs, and 18228 litters of Black
Slavonian pigs. DNA isolation was done on twenty individuals of the Turopolje, Black
Slavonian, and Landrace pig breeds, as well as on reproductively active, non-related Banija
spotted sows and boars that were included in the study (N=30). 24 MS and 16 MS markers
were selected from the ISAG-FAO recommendation list. 25 Banija spotted pigs were used
for the genotyping of the candidate genes for litter size (ESR1 and RBP4), with at least one
litter recorded and assessed using the PCR-RFLP method.
The average body mass of the sows and boars that were measured was roughly the same
(162.6 kg vs. 162.2 kg), with the sows having slightly bigger variances between the
minimum and maximum values (209 kg) than the boars (155 kg). Sows measured 72.1 cm
at the withers, which was 5 cm less than boars’ average height. Boars had values that were,
on average, 5-7 cm higher than sows for both the height at the withers and the height to the
base of the tail. The sows’ average carcass length was 116.3 cm, which was roughly 2 cm
less than the boars’. Chest circumference (131.1 cm or +7 cm), abdominal circumference
(132.6 cm or +7.4 cm), and chest width (33.6 cm or +0.3 cm) were all greater in sows than
in boars. The average head length and head width measured in sows were 31.1 cm and
16.1 cm, respectively. The average nose length of sows was found to be shorter (-0.7 cm)
than that of boars, whereas their average nose width was slightly greater (+0.3 cm).
Comparing male categories (boars and young boars) to female categories (sows and gilts),
the measured values of tail length were greater in the former. With respect to ear position,
the majority of the individuals under analysis had flat ears, with semi-flat ears following
closely behind. Only one male (a boar) showed projecting ears. In terms of back line
appearance, 91.7% of sows and all other categories (boars, gilts, and young boars) have a
straight back line. Only 8.3% of sows had a convex dorsal line. Regarding the nasal profile
of BS pigs, 56.8% of sows and 66.7% of boars were found to have a flat nasal profile. On
the other hand, sows accounted for 43.2% and boars for 33.0% of the total number of
individuals with a sunken nasal profile. Of the sows, 55.6% had short hair and 25% had
boars; of the sows, 44.4% had long hair and 75% of the boars had short hair. Of the sows,
52.8% had black pigment on their hooves, while the boars had 8.3%. 52.8% of sows and
58.3% of boars had a flat tail, according to an analysis of the tail’s appearance in several
BS pig groups. On average, 51.9% of the body surface was covered in black patterns,
compared to 48.1% in white patterns. In 50% of boars with the right ear and 66.7% of boars
with the left, the pigment content was undetermined. For both the left and right ears, more
than one-third of the coloured ear was present in 64.9% and 62.2% of the sows,
respectively. The average litter size of 184 BS pigs, or 8.5 total born (TB) or 7.5 born alive
(FL) piglets, was found by analysis of the observed litters. A slightly greater proportion of
FL female piglets (3.9) than male piglets (3.6) was discovered after the sexes’ relationship
was analysed. There were statistically significantly lower values (P<0.05) of all observed
fertility indicators in the two other original breeds of pigs in the Republic of Croatia, the
Turopolje pig (TP) and the Black Slavonian pig (BSP), as compared to BS.
Genotype frequencies for both examined marker genes (ESR1 and RBP4) in the BS pig
population do not show significant deviation from the Hardy-Weiberg equilibrium. The ESR1
gene is characterised by a high proportion of allele A (0.78), i.e., a high proportion of
homozygous individuals of the AA genotype (0.60) and heterozygous AB (0.36), while only
one individual had the BB genotype (0.04). Allele B (0.60) is the most common and accounts
for the biggest proportion of genotypes with BB (0.44), according to the study of RBP4 gene
polymorphism. Next in frequency (0.32) are heterozygotes, with the AA of homozygous
individuals having the lowest number observed. In BS pigs, the polymorphism of the ESR1
gene did not significantly affect fertility indicators; however, in primiparous sows, this
influence is evident with respect to the RBP4 gene.
For the purposes of defining the genetic diversity of the BS pig breed and its differentiation
in relation to other native and pure pig breeds in Croatia, an analysis of genetic variability
and comparison with Turopolje pigs (TP), and Black Slavonian pigs (BSP), and pure pig
breeds bred in the Republic of Croatia, Landrace (L), Large Yorkshire (LY), Duroc (D), and
Pietrain (P) were done. According to the findings, BS had the highest average number of
alleles per locus (7.36), whereas TP had the lowest average (2.92). In Y (0.7221), the
observed heterozygosity (Ho) was highest, whereas in TP (0.342), it was lowest. The
inbreeding coefficient was the highest for TP (0.08830), slightly lower for BS (0.08691) and
the lowest for D (-0.01172). The highest FST value for the Banija spotted pig breed was
0.2868 (between BS and TP), while the lowest was 0.1052 between BS and BSP. Of the
pure breeds, the Pietrain (0.2492) is the farthest from it, and the Landrace (0.206) is the
closest. An average of 578 animals was genotyped using 16 MS markers, 127 of which
were BS. The observed heterozygosity (Ho) in the BS was 0.6349, and the expected
heterozygosity (He) was 0.6566, while the lowest values were recorded in the Turopolje
pigs (Ho 0.369; He 0.3787), and the highest in the Large Yorkshire pigs (Ho 0, 7221; He
0.7059). The lowest FST value was recorded between BS and L (0.0878), while the highest
was 0.3112 (between BS and TP). Out of all the native pig breeds, BS and BSP had the
closest fixation index value, at 0.1079. As a result, the BS pig population exhibits high
genetic diversity within itself and differs genetically from other similar and geographically
close pig populations, such as the Black Slavonian or Turopolje pigs, with whom it shares
common ancestors
Applicability of cloud-based video games in education
No full textVideoigre su društveni fenomen koji se već desetljećima intenzivno istražuje, a igranje videoigara je pozitivno povezano s uspjehom u školi. Istraživanja su pokazala da korištenje videoigara u nastavi ima pozitivan utjecaj na: čitanje i pisanje, geometrijsko i matematičko razmišljanje, strateško razmišljanje i zaključivanje, kritičko promišljanje, rješavanje problema i kreativnost, STEM područje, učenje jezika kao i na učeničku motivaciju i zadovoljstvo nastavom. Cilj ove disertacije je istraživanje kvalitete korisničkoga iskustva pri upotrebi videoigara baziranih na računalnom oblaku u odgojno-obrazovne svrhe te razvijanje pristupa za integraciju ovih igara u odgojno-obrazovni proces pri čemu će se uzeti u obzir postojeća ograničenja tehnologije i infrastrukture, kao i potrebe i zahtjeve osnovnoškolskih učitelja. Dodatno, cilj je bio izrađivanje optimizacijskoga modela koji će olakšati implementaciju videoigara u odgojno-obrazovni proces putem videoigara baziranih na računalnom oblaku. Tijekom prve faze istraživanja, distribuirani su anketni upitnici učiteljima razredne i predmetne nastave za ispitivanje stavova o korištenju videoigara u obrazovanju. Analiza je pokazala statistički značajne razlike u stavovima između ove dvije skupine, učitelji razredne nastave pokazali su veću sklonost korištenju videoigara kao obrazovnih alata. U drugoj fazi, testirane su komercijalne platforme za videoigre bazirane na računalnom oblaku kako bi se provjerilo zadovoljavaju li obrazovne potrebe učitelja. Rezultati su potvrdili hipotezu da platforme zadovoljavaju te potrebe, pružajući odgovarajuće resurse. Treća faza obuhvatila je ocjenu tehničkih specifikacija školskih informatičkih učionica kako bi se utvrdila njihova prikladnost za korištenje videoigara. Odabrana je učionica koja je najbolje ispunjavala tehničke i obrazovne kriterije te su odabrane obrazovne igre Tricky Towers za osnovnoškolsko i Age of Caesar za nastavu povijesti. Četvrta faza uključivala je preliminarno istraživanje korištenjem GeForce NOW platforme, tijekom kojeg su studenti igrali igre u različitim postavkama. Razvijen je model optimizacije temeljen na analizi iskustvene kvalitete igara. U petoj fazi istraživanja proveo se kvazieksperiment na nastavnom satu pri čemu je mjerena iskustvena kvaliteta korištenja videoigara u nastavi. Rezultati su pokazali da igranje lokalno i putem računalnoga oblaka nije dovelo do statistički značajnih razlika u iskustvenoj kvaliteti, čime je potvrđena hipoteza da nema razlike u kvaliteti između lokalnoga igranja i igranja putem računalnoga oblaka.Video games have developed into a significant social phenomenon that has attracted the attention of researchers for decades. Over the past few years, the gaming industry has surpassed both the global film industry and the sports industry in North America in terms of revenue. There exists a positive correlation between playing video games and academic success, particularly in STEM education. Studies from the Netherlands have shown that most students with computer skills, such as text writing and basic image processing, have experience playing video games. Video game players have achieved better results on PISA tests in reading, mathematics, and science. Notably, playing strategic video games is linked to enhanced problem-solving skills, which are also reflected in school grades. In the scientific context, serious games, which are designed not solely for entertainment but with educational purposes, are emphasized. These games use multimodal interaction to enhance user experience, allowing players to communicate naturally with both virtual and physical worlds. Serious games, incorporating various media such as text, graphics, animation, sound, and haptics, have demonstrated potential in diverse contexts including education, training, health, and interpersonal communication. The use of video games in education, including genres suitable for specific ages, positively affects student motivation, satisfaction with lessons, and various aspects of learning such as reading, writing, mathematical and geometrical reasoning, strategic thinking, critical thinking, creativity, STEM, and language learning. Despite the significant potential of video games as learning tools, their application for educational purposes has remained rare. Major barriers include technical limitations such as infrastructure and hardware, a lack of IT competencies among teachers, a shortage of quality educational games suitable for classroom use, and high financial costs associated primarily with game acquisition. Successfully integrating video games into the educational process is crucial, requiring the establishment of advanced ICT infrastructure supported by modern technologies such as cloud computing. Cloud-based video games offer an innovative way of organizing online gaming, enabling gameplay that is entirely stored and processed on cloud servers. This technology delivers highquality video to users while their inputs are sent to the server. Cloud games can overcome many of the challenges mentioned as they do not require powerful hardware, reduce the need for specific knowledge among teachers, allow access to the latest games with advanced graphics, and decrease the number of licenses needed. Using cloud games in an educational context offers numerous advantages while eliminating key barriers, posing research challenges related to optimizing interactive video streaming to maximize Quality of Experience (QoE) in computer classrooms. The concept of Quality of Experience finds its application in the telecommunications sector, referring to the evaluation of user satisfaction when using certain technological products or services. This topic has been continuously researched for many years, and although it is welldeveloped, it still presents a field open for the exploration of new technological services, including the under-researched area of educational games in cloud environments. Quality of Experience is assessed both subjectively, using the Mean Opinion Score (MOS), and objectively based on technical Quality of Service (QoS) parameters. Unlike the technically focused QoS, improving services and enhancing user satisfaction crucially depends on understanding users' perceptions of quality. The challenge in introducing cloud-based video games into education involves selecting appropriate games for different educational programs. This research area requires an interdisciplinary approach that merges technical and social research to apply advanced technological solutions in education. This doctoral dissertation has investigated how using cloudbased video games affects the Quality of Experience in the educational setting and developed a methodology for their integration into teaching, taking into account technical and infrastructural limitations and the requirements of teachers for using video games for educational purposes. The dissertation aimed to explore the quality of user experience when using cloud-based video games for educational purposes and to develop an approach for integrating these games into the educational process, considering existing technology and infrastructure limitations, as well as the needs and demands of elementary school teachers. Additionally, an optimization model was created to facilitate the implementation of video games in education through cloud technology. The research addressed the following hypotheses: H1: There is no statistically significant difference in the opinions and attitudes about using video games between elementary and subject teachers. H2: Available commercial platforms for using cloud-based video games meet teachers' needs. H3: There is no statistically significant difference in the Quality of Experience when using games locally and on the cloud. The research was conducted in several phases: During the first phase of the research, survey questionnaires were distributed to primary and subject teachers to investigate their views on the use of video games in an educational context. The analysis of the collected data revealed statistically significant differences in attitudes between these two groups of teachers, which partially confirmed the hypothesis "There is no statistically significant difference in opinions and attitudes regarding the use of video games among primary and subject teachers." Specifically, primary teachers expressed a greater propensity to use video games as educational tools compared to their subject teacher colleagues. In the second phase of the research, various commercial platforms for cloud-based video games were evaluated to determine if they meet the educational needs of teachers. The results confirmed the hypothesis "Available commercial platforms for using video games in the cloud meet teachers' needs," as the platforms provided resources that matched the teachers' requirements for integrating video games into educational plans. The third phase of research involved assessing the technical specifications of computer classrooms, aiming to determine their capability for implementing video games in teaching. Based on these analyses, a classroom that best met the technical and educational requirements was selected. Additionally, two educational games, "Tricky Towers" for primary education and "Age of Caesar" for subject teaching of history, were selected. In the fourth phase, a preliminary study was conducted using the GeForce NOW platform, where students played video games under various technical settings. Based on the performance and Quality of Experience analysis, an optimization model was developed. In the fifth phase of the study, real-time testing of the model in the classroom involved playing games both locally and through the cloud, measuring video quality, fluidity, and overall Quality of Experience. The results showed that there was no statistically significant difference in Quality of Experience between local and cloud gaming, thereby confirming the hypothesis that "There is no statistically significant difference in Quality of Experience when using games locally and on the cloud." The scientific contribution of the work is reflected in the analysis of teachers' opinions and attitudes towards video games in teaching and the assessment of their needs for using games in teaching through cloud computing. A methodology for introducing cloud-based games into the teaching process was also developed. An optimization model for the Quality of Experience of using games in cloud-based teaching was created, considering existing technical and infrastructural limitations, and the Quality of Experience of cloud-based video games was determined. The practical contribution of this doctoral dissertation lies in multiple aspects of enhancing the educational process through the integration of cloud-based video games. A detailed analysis of available video games on commercial platforms and their mapping to specific educational areas and thematic units of the curriculum was provided. This enabled teachers to easily identify relevant games that could be used as educational tools, tailored to the curriculum and specific educational goals. The developed methodology for introducing video games into teaching provided a clear and systematic approach that helps teachers and educational institutions efficiently integrate video games into the teaching process. This methodology includes steps from identifying teachers' needs and selecting appropriate games to implementing games in teaching and evaluating their effectiveness. By developing a model that precisely determines how many computers and what technical specifications are necessary for optimal functioning of games in the cloud, the dissertation provided key information for planning and establishing adequate IT infrastructure in schools. The optimization model allows teachers to maximize the Quality of Experience in learning with minimal technical requirements, thereby reducing potential barriers to implementation, such as high costs and technical limitations. The practical contribution of the dissertation also extends to improving student motivation and engagement through innovative and interactive learning methods. Using cloud-based video games as educational tools can increase students' interest in subjects, improve their understanding of complex concepts, and enhance learning achievements
Syndecans, exostosins and sulfo-transpherases as potential synovial inflammation moderators in patients with hip osteoarthritis
No full textPozadina istraživanja: Uvriježeno je mišljenje da je postupno propadanje zglobne hrskavice središnji događaj u nastanku i progresiji osteoartritisa (OA), no nedavne su studije pokazale iznimnu važnost sinovitisa niskog stupnja u progresiji OA. Poznato je da sindekanska (SDC) obitelj membranskih proteoglikana sudjeluje u regulaciji upale, ali postoje ograničeni dokazi koji razmatraju ulogu sindekana u OA sinovitisu. Cilj mog rada bio je istražiti obrasce ekspresije sindekana-1 (SDC1), sindekana-2 (SDC2) i sindekana-4 (SDC4) u sinovijalnoj membrani (intimi i subintimi) OA kuka, kao i egzostozina (EXT) i sulfotransferaza (NDST) (enzima uključenih u polimerizaciju i modifikaciju heparan-sulfatnih lanaca sindekana). Metode: kirurški prikupljene uzorke sinovijalne ovojnice pacijenata s OA podijelio sam u dvije skupine s obzirom na izraženost sinovitisa ocijenjenog histološkim bodovanjem sinovitisa po Krennu. Zatim sam analizirano imunohistokemijsku ekspresiju SDC1, SDC2, SDC4, EXT1, EXT2, NDST1 i NDST2 u sinovijalnoj intimi i subintimi i potom je usporedio s kontrolnom skupinom (pacijenti s prijelomom vrata bedrene kosti, bez OA). Dodatno sam istražio povezanost ekspresije ovih molekula s kliničkim i radiološkim pokazateljima težine osteoartritisa kuka. Rezultati: prema mojoj studiji, imunoekspresija SDC1, NDST1 i EXT2 značajno je povećana u stanicama intime OA sinovijalne membrane u bolesnika s nižim histološkim rezultatom sinovitisa, i SDC4 u bolesnika s višim rezultatom sinovitisa, u usporedbi s kontrolama bez OA. Razlika u ekspresiji SDC2 između OA i ne-OA skupine je beznačajna. Nasuprot tome, klinički i radiološki pokazatelji težine OA najbolje koreliraju s ekspresijom sindekana-2, od svih ispitivanih molekula, kako u intimalnom tako i u subintimalnom sloju sinovijalne ovojnice. Zaključci: Čini se da SDC1, SDC4, NDST1 i EXT2 imaju ulogu kao moderatori upale u OA sinovitisu niskog stupnja. Tumačenje rezultata je teško zbog delikatnih interakcija između testiranih molekula i njihovih potencijalnih pro- i protuupalnih učinaka. Usprkos tome, mišljenja sam da rezultati moje studije dokazuju da bi upalne mehanizme povezane sa sindekanima trebalo dodatno istražiti kao potencijalne markere progresije bolesti i terapijskog cilja u OA.Background: The gradual deterioration of articular cartilage was thought to be the central event in osteoarthritis (OA), but recent studies demonstrated importance of low-grade synovitis in progression of OA. Syndecan (SDC) family of membrane proteoglicans is known to be involved in regulation of inflammation but there is a limited evidence considering the role of syndecans in OA synovitis. The aim of my study was to investigate hip OA synovial membrane expression patterns (intimal and subintimal) of syndecan-1 (SDC1), syndecan-2 (SDC2), and syndecan-4 (SDC4) as well as exostosins (EXT) and sulfotransferases (NDST) (enzymes involved in polimerisation and modification of syndecans’ heparan-sulfat chains). Methods: surgically collected synovial membrane samples of patients with OA were divided into two groups according to their Krenn synovitis score grading. Immunohistochemical expression of SDC1, SDC2, SDC4, EXT1, EXT2, NDST1, and NDST2 in synovial intima and subintima was then analyzed and compared with control group (patients with femoral neck fracture, without OA). Additionally, I investigated the association of the expression of these molecules with clinical and radiological indicators of hip osteoarthritis severity. Results: according to my study, immunoexpression of SDC1, NDST1 and EXT2 is significantly increased in intimal cells of OA synovial membrane in patients with lower histological synovitis score, and SDC4 in patients with higher synovitis score, in comparison with non-OA controls. Difference in expression of SDC2 among OA and non-OA group is insignificant. Contrary, clinical and radiological indicators of OA severity correlate best with syndecan-2 expression, of all investigated molecules, both in intimal and subintimal layers of synovial membrane. Conclusions: SDC1, SDC4, NDST1 and EXT2 seem to be involved as inflammation moderators in low-grade OA synovitis. The interpretation of the results is difficult due to the delicate interactions between the tested molecules and their potential pro- and anti-inflammatory effects. However, I am of the opinion that the results of my study prove that syndecan related inflammation pathways should be further investigated as potential markers of disease progression and therapeutic goal in OA
Impact of social media influencers on brand equity and purchase intentions in fashion industry
No full textRazvojem interneta i društvenih mreža kao ključnih platformi za komunikaciju u današnje doba, pojavila se nova generacija utjecajnih osoba na društvenim mrežama koje se mogu pojmovno odrediti kao pojedinci koji kroz direktnu komunikaciju i iznošenje stavova putem korisničkih profila na društvenim mrežama stvaraju široku mrežu pratitelja te svojim djelovanjem snažno utječu na vlastitu publiku i širu javnost. U svrhu doprinosa postojećim akademskim spoznajama, ova doktorska disertacija bavi se analiziranjem učinaka utjecajnih osoba na društvenim mrežama na tržišnu vrijednost marke i kupovnu namjeru potrošača kroz pregled postojeće literature, te primarno kvalitativno i kvantitativno istraživanje kako bi iznjedrila nova saznanja o toj aktualnoj temi.
Kvalitativno istraživanje otkrilo je da ispitanici najviše prate utjecajne osobe na društvenim mrežama na platformama Instagram, Facebook i TikTok, najviše vole slike kao tip sadržaja objave te da jednako vole pratiti sadržaje stranih utjecajnih osoba na društvenim mrežama kao i domaćih s lokalnog govornog područja. Kod formiranja stavova o utjecajnim osobama na društvenim mrežama, kao ključne odrednice se ističu kvaliteta sadržaja, učestalost objava, percepcija povjerenja, integriteta, vjerodostojnosti i dosljednosti koje utjecajna osoba na društvenim mrežama ulijeva, fizičke karakteristike utjecajne osobe na društvenim mrežama te usklađenost između objavljenog proizvoda i utjecajne osobe na društvenim mrežama.
Kvantitativno istraživanje u ovom radu empirijski provjerava strukturni model s pretpostavljene tri glavne hipoteze i četrnaest podhipoteza, upotrebom metode modeliranja strukturnih jednadžbi. Rezultati provedenog kvantitativnog istraživanja ukazuju na pouzdanost i privlačnost kao dvije ključne percipirane karakteristike koje imaju pozitivan i značajan učinak na stav o utjecajnim osobama na društvenim mrežama. Nadalje, utvrđen je značajan i pozitivan učinak stava potrošača o utjecajnim osobama na društvenim mrežama na sve dimenzije tržišne vrijednosti marke iz perspektive potrošača, odnosno, najveći na asocijacije o marki i percipiranu kvalitetu te nešto manji na svijest o marki i lojalnost marki. U konačnici, temeljeno na prikupljenim podacima, tri od ukupno četiri dimenzije tržišne vrijednosti marke imaju pozitivan i značajan utjecaj na kupovnu namjeru potrošača za marke modne industrije, od čega najveći utjecaj ima lojalnost marki. Dodatno su proučeni indirektni učinci, koji sugeriraju da percipirane karakteristike utjecajnih osoba na društvenim mrežama imaju indirektan utjecaj na dimenzije tržišne vrijednosti marke, a stav o utjecajnim osobama na društvenim mrežama koje objavljuju marku iz modne industrije na kupovnu namjeru potrošača.The development of the Internet and social networks as key platforms for communication in today's age has led to the emergence of a new generation of influential individuals on social networks. These individuals, called social media influencers, can be conceptually defined as those who, through direct communication and expressing their views via social network user profiles, create a wide network of followers and significantly influence their own audience and the general public. This doctoral dissertation aims to contribute to existing academic knowledge by analyzing the effects of social media influencers on consumer based brand equity and consumer purchase intention. This analysis includes a review of existing literature, as well as primary qualitative and quantitative research, to generate new insights on this current topic.
Qualitative research revealed that respondents primarily follow influencers on Instagram, Facebook, and TikTok. They prefer image-based content and enjoy following both foreign and local influencers. Key factors in forming opinions about influencers include content quality, posting frequency, perceived trustworthiness, integrity, credibility, and consistency, physical characteristics of the influencer, and the compatibility between the published product and the influencer. The insights gained from the qualitative research about the key characteristics of influencers in shaping consumer attitudes were directly applied in the quantitative research.
The quantitative research in this dissertation empirically tests the structural model with three main hypotheses and fourteen sub-hypotheses using the structural equation modelling method. The results indicate that trustworthiness and attractiveness are two key perceived characteristics that positively and significantly affect attitudes towards social media influencers. Additionally, a positive and significant effect of consumer attitudes towards influencers on all dimensions of brand equity was found, with the greatest impact on brand associations and perceived quality, and somewhat less on brand awareness and brand loyalty. Ultimately, the data shows that three of the four dimensions of brand equity positively and significantly impact consumers' purchase intention for fashion industry brands, with brand loyalty having the greatest impact. Furthermore, indirect effects were studied, suggesting that the perceived characteristics of social media influencers indirectly influence the dimensions of brand equity, and that attitudes towards influencers who promote fashion industry brands indirectly influence consumer purchase intention