Opin vísindi

 

Flokkar í Opnum vísindum

Veldu flokk til að skoða.

Niðurstöður 1 - 9 af 9

Nýlega bætt við

Verk
Cohort profile : the multigeneration Respiratory Health in Northern Europe, Spain and Australia (RHINESSA) cohort
(2022-06-01) Svanes, Cecilie; Johannessen, Ane; Bertelsen, Randi Jacobsen; Dharmage, Shyamali; Benediktsdóttir, Bryndís; Bråbäck, Lennart; Gíslason, Þórarinn; Holm, Mathias; Jõgi, Oskar; Lodge, Caroline J.; Malinovschi, Andrei; Martinez-Moratalla, Jesus; Oudin, Anna; Sánchez-Ramos, José Luis; Timm, Signe; Janson, Christer; Real, Francisco Gomez; Schlünssen, Vivi; Faculty of Medicine; Health Sciences
Purpose The Respiratory Health in Northern Europe, Spain and Australia (RHINESSA) cohort was established to (1) investigate how exposures before conception and in previous generations influence health and disease, particularly allergies and respiratory health, (2) identify susceptible time windows and (3) explore underlying mechanisms. The ultimate aim is to facilitate efficient intervention strategies targeting multiple generations. Participants RHINESSA includes study participants of multiple generations from ten study centres in Norway (1), Denmark (1), Sweden (3), Iceland (1), Estonia (1), Spain (2) and Australia (1). The RHINESSA core cohort, adult offspring generation 3 (G3), was first investigated in 2014-17 in a questionnaire study (N=8818, age 18-53 years) and a clinical study (subsample, n=1405). Their G2 parents participated in the population-based cohorts, European Community Respiratory Heath Survey and Respiratory Health In Northern Europe, followed since the early 1990s when they were 20-44 years old, at 8-10 years intervals. Study protocols are harmonised across generations. Findings to date Collected data include spirometry, skin prick tests, exhaled nitric oxide, anthropometrics, bioimpedance, blood pressure; questionnaire/interview data on respiratory/general/reproductive health, indoor/outdoor environment, smoking, occupation, general characteristics and lifestyle; biobanked blood, urine, gingival fluid, skin swabs; measured specific and total IgE, DNA methylation, sex hormones and oral microbiome. Research results suggest that parental environment years before conception, in particular, father's exposures such as smoking and overweight, may be of key importance for asthma and lung function, and that there is an important susceptibility window in male prepuberty. Statistical analyses developed to approach causal inference suggest that these associations may be causal. DNA methylation studies suggest a mechanism for transfer of father's exposures to offspring health and disease through impact on offspring DNA methylation. Future plans Follow-up is planned at 5-8 years intervals, first in 2021-2023. Linkage with health registries contributes to follow-up of the cohort.
Verk
Physicochemical and Stability Evaluation of Topical Niosomal Encapsulating Fosinopril/γ-Cyclodextrin Complex for Ocular Delivery
(2022-05-27) Hnin, Hay Marn; Stefánsson, Einar; Loftsson, Þorsteinn; Asasutjarit, Rathapon; Charnvanich, Dusadee; Jansook, Phatsawee; Faculty of Medicine; Faculty of Pharmaceutical Sciences
This study aimed to develop a chemically stable niosomal eye drop containing fosinopril (FOS) for lowering intraocular pressure. The effects of cyclodextrin (CD), surfactant types and membrane stabilizer/charged inducers on physiochemical and chemical properties of niosome were evaluated. The pH value, average particle size, size distribution and zeta potentials were within the acceptable range. All niosomal formulations were shown to be slightly hypertonic with low viscosity. Span® 60/dicetyl phosphate niosomes in the presence and absence of γCD were selected as the optimum formulations according to their high %entrapment efficiency and negative zeta potential values as well as controlled release profile. According to ex vivo permeation study, the obtained lowest flux and apparent permeability coefficient values confirmed that FOS/γCD complex was encapsulated within the inner aqueous core of niosome and could be able to protect FOS from its hydrolytic degradation. The in vitro cytotoxicity revealed that niosome entrapped FOS or FOS/γCD formulations were moderate irritation to the eyes. Furthermore, FOS-loaded niosomal preparations exhibited good physical and chemical stabilities especially of those in the presence of γCD, for at least three months under the storage condition of 2–8 °C.
Verk
Missense variants causing Wiedemann-Steiner syndrome preferentially occur in the KMT2A-CXXC domain and are accurately classified using AlphaFold2
(2022-06-21) Reynisdóttir, Tinna; Anderson, Kimberley Jade; Boukas, Leandros; Björnsson, Hans Tómas; Faculty of Medicine
Wiedemann-Steiner syndrome (WDSTS) is a neurodevelopmental disorder caused by de novo variants in KMT2A, which encodes a multi-domain histone methyltransferase. To gain insight into the currently unknown pathogenesis of WDSTS, we examined the spatial distribution of likely WDSTS-causing variants across the 15 different domains of KMT2A. Compared to variants in healthy controls, WDSTS variants exhibit a 61.9-fold overrepresentation within the CXXC domain–which mediates binding to unmethylated CpGs–suggesting a major role for this domain in mediating the phenotype. In contrast, we find no significant overrepresentation within the catalytic SET domain. Corroborating these results, we find that hippocampal neurons from Kmt2a-deficient mice demonstrate disrupted histone methylation (H3K4me1 and H3K4me3) preferentially at CpG-rich regions, but this has no systematic impact on gene expression. Motivated by these results, we combine accurate prediction of the CXXC domain structure by AlphaFold2 with prior biological knowledge to develop a classification scheme for missense variants in the CXXC domain. Our classifier achieved 92.6% positive and 92.9% negative predictive value on a hold-out test set. This classification performance enabled us to subsequently perform an in silico saturation mutagenesis and classify a total of 445 variants according to their functional effects. Our results yield a novel insight into the mechanistic basis of WDSTS and provide an example of how AlphaFold2 can contribute to the in silico characterization of variant effects with very high accuracy, suggesting a paradigm potentially applicable to many other Mendelian disorders.
Verk
Screen Time and Body Image in Icelandic Adolescents : Sex-Specific Cross-Sectional and Longitudinal Associations
(2022-01-24) Hrafnkelsdottir, Soffia M.; Brychta, Robert J.; Rognvaldsdottir, Vaka; Chen, Kong Y.; Johannsson, Erlingur; Guðmundsdottir, Sigridur L.; Arngrimsson, Sigurbjorn A.; Faculty of Health Promotion, Sports and Leisure Studies
Studies of adolescent body image and screen use are mostly limited to girls, and longitudinal data are scarce. We examined cross-sectional and longitudinal associations between these variables in mid-adolescent boys and girls. Data was collected when participants were at age 15 and 17, by questionnaire and objective measurements (n = 152 had complete data). Sex-specific linear regression was used to explore cross-sectional and longitudinal associations of self-reported screen use (total use, and time spent in gaming, TV/DVD/internet-based watching and internet use for communication) and body image, adjusting for vigorous physical activity, symptoms of depression, and body composition. Screen time was negatively associated with body image at both time points, although more strongly at age 15, and for girls only. Gaming and TV/DVD/internet watching was more strongly associated with body image than internet use for communication. Girls with above median screen time at both ages had 14% lower body image score at age 17 than girls with below median screen time at both time points. Our results suggest that screen use is likely to play a role in the development of body dissatisfaction among adolescent females. Limiting screen time may, therefore, help to mitigate body dissatisfaction in adolescent girls.
Verk
Hreyfing íslenskra grunnskólanema
(2022-02-08) Gísladóttir, Þórdís Lilja; Vilhjálmsson, Rúnar; Rögnvaldsdóttir, Vaka; Deild heilsueflingar, íþrótta og tómstunda; Heilbrigðisvísindasvið
Gildi hreyfingar fyrir líkamlega og andlega heilsu er vel þekkt. Þrátt fyrir þá vitneskju dregur úr hreyfingu frá barnsaldri til unglingsára og almennt er hreyfingu ábótavant. Því er mikilvægt að kanna hreyfingu barna og unglinga með það fyrir augum að efla hana og sporna við hreyfingarleysi. Markmið þessarar rannsóknar var að kanna umfang líkamlegrar hreyfingar íslenskra grunnskólanema í 6., 8. og 10. bekk og tengsl hennar við kyn, aldur, uppruna, fjölskyldugerð, efnahag og búsetu. Sérstaklega var athugað hve hátt hlutfall nemendanna næði ráðlagðri 60 mínútna hreyfingu daglega. Unnið var úr gögnum úr landskönnuninni Heilsa og lífskjör skólanema (Health Behavior in School-aged Children - HBSC) sem fór fram árið 2018. Alls tóku 6.102 nemendur í 6., 8. og 10. bekk úr 86 grunnskólum á landinu þátt í rannsókninni. Spurningalistar voru lagðir fyrir nemendur og meðal annars var spurt um fjölda daga á viku sem þátttakendur stunduðu „líkamlega hreyfingu samanlagt í 60 mínútur eða meira á dag“. Þá var einnig spurt um kyn og bekkjardeild, efnahagslega stöðu fjölskyldu, uppruna foreldra, fjölskyldugerð og búsetu. Að meðaltali stundaði nemendahópurinn líkamlega hreyfingu í 4,5 daga í viku. Einungis 21% nemenda náði viðmiði um ráðlagða daglega hreyfingu. Fleiri piltar en stúlkur náðu viðmiðum um hreyfingu og fleiri nemendur í 6. bekk samanborið við eldri nemendur. Nemendur sem tilheyrðu fjölskyldum með lakari efnahag, bjuggu ekki með báðum kynforeldrum, eða áttu foreldra af erlendum uppruna, náðu síður viðmiðum um ráðlagða hreyfingu. Ekki var munur á hreyfingu grunnskólanema eftir búsetu þeirra. Vinna þarf að hreyfieflingu grunnskólanema með fræðslu um gildi hennar, daglegum hreyfistundum á skólatíma og markvissum íþróttatímum. Jafna þarf þátttöku barna í íþróttum utan skólans með aðkomu sveitarfélaganna. Fjölga þarf möguleikum til hreyfingar fyrir alla utan húss og innan í sveitarfélögum landsins.