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A systematic review of the psychometric properties of Beck Youth Inventory in Iceland
No full textTo access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadMarkmið þessarar greinar var að kanna próffræðilega stöðu Sjálfsmatskvarða Becks fyrir börn
og unglinga (BYI) í íslenskri útgáfu með aðferð kerfisbundins yfirlits (e. systematic review).
Sjálfsmatskvarðar Becks samanstanda af fimm undirkvörðum með 20 atriðum hver, sem meta
sjálfsmynd, kvíða, þunglyndi, reiði og hegðunarvanda hjá ungmennum á aldrinum 7-18 ára. Leitað
var kerfisbundið að öllum rannsóknum sem lögðu kvarðana fyrir íslenskt úrtak í gagnagrunnum
Google Scholar, PubMed og Skemmunnar og þær teknar saman. Alls fundust níu greinar og handrit
sem fjölluðu um próffræðilega eiginleika kvarðanna. Niðurstöður gáfu til kynna gott innra samræmi
á bilinu 0,71-0,96. Aðgreiningar- og samleitniréttmæti var óviðunandi þar sem meðal annars var há
innbyrðis fylgni á milli undirkvarða BYI og fylgni við aðra lista sem mátu ólíkar hugsmíðar. Einnig
bentu niðurstöður þáttagreiningar til þess að listinn aðgreindi ekki með fullnægjandi hætti á milli
hugsmíðanna kvíða, þunglyndis og reiði, en niðurstöður íslenskra rannsókna hafa bent til þess
að þessar þrjár hugsmíðir myndi saman einn þátt. Þessar niðurstöður eru í samræmi við erlendar
rannsóknir, en helsti styrkleiki listans er mikið innra samræmi. Hins vegar er aðgreiningar- og
samleitniréttmæti listans óviðunandi. Einnig er ekki vitað hvaða notagildi kvarðarnir hafa í klínísku
úrtaki með tilliti til viðmiðsréttmætis og hvort kvarðarnir henti til að meta árangur meðferðar eða
breytingar á einkennum yfir tíma. Próffræðilegir eiginleikar sjálfsmyndar- og hegðunarvandakvarða
BYI meðal íslenskra rannsókna eru að mestu viðunandi til góðir. Hvað varðar kvíða-, þunglyndis- og
reiðikvarða BYI getum við ekki mælt með notkun þeirra, hvorki í almennum né klínískum tilgangi
en hins vegar mælum við með endurskoðun þessara þriggja undirkvarða.
Efnisorð: Sjálfsmatskvarðar Becks, skimun, próffræðilegir eiginleikar, börn, unglingarThe goal of this study was to perform a systematic review
to estimate the psychometric properties of the Icelandic
translation of the Beck Youth Inventory (BYI) in Iceland.
The BYI consists of five independent subscales each
containing 20 statements measuring self-concept, anxiety,
depression, anger and disruptive behaviour in youths
aged 7-18 years old. Online databases were searched for
researches employing the Icelandic version of the BYI.
The databases used to search included Google Scholar,
PubMed and Skemman. The search concluded nine
studies, whose results included psychometric properties
of the BYI. Results showed good internal consistency
ranging from 0.71-0.96. Convergent validity showed
medium to high correlation with scales measuring related
constructs. However, divergent validity could not
be established as the BYI subscales were found to be
highly correlated internally as well as with other scales
measuring unrelated constructs. Results from factor analyses
indicated the BYI does not discriminate adequately
between anxiety, depression and anger, and it seems from
Icelandic research that these constructs form one latent
factor. These results are consistent with international
research, as internal reliability and convergent validity
have been shown to be the strengths of the BYI. Nevertheless,
results on divergent validity are unsatisfactory.
Clinical applications of the BYI are as of yet doubtful
with regards to criterion validity and suitability to measure
progress in treatment or changes in symptoms over time.
Self-concept and disruptive behaviour showed adequate
to good psychometric properties. Concerning the scales
on anxiety, depression and anger, we cannot recommend
their general nor clinical usage, but suggest revision of
these three subscales.
Keywords: Beck Youth Inventory, psychometric properties,
screening, children, adolescenc
Hjúkrun í „heimsþorpinu“
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Molecular genetics of inherited retinal degenerations in Icelandic patients.
Get PDFTo access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadThe study objective was to delineate the genetics of inherited retinal degenerations (IRDs) in Iceland, a small nation of 364.000 and a genetic isolate. Benefits include delineating novel pathogenic genetic variants and defining genetically homogenous patients as potential investigative molecular therapy candidates. The study sample comprised patients with IRD in Iceland ascertained through national centralized genetic and ophthalmological services at Landspitali, a national social support institute, and the Icelandic patient association. Information on patients' disease, syndrome, and genetic testing was collected in a clinical registry. Variants were reevaluated according to ACMG/AMP guidelines. Overall, 140 IRD patients were identified (point prevalence of 1/2.600), of which 70 patients had a genetic evaluation where two-thirds had an identified genetic cause. Thirteen disease genes were found in patients with retinitis pigmentosa, with the RLBP1 gene most common (n = 4). The c.1073 + 5G > A variant in the PRPF31 gene was homozygous in two RP patients. All tested patients with X-linked retinoschisis (XLRS) had the same possibly unique RS1 pathogenic variant, c.441G > A (p.Trp147X). Pathologic variants and genes for IRDs in Iceland did not resemble those described in ancestral North-Western European nations. Four variants were reclassified as likely pathogenic. One novel pathogenic variant defined a genetically homogenous XLRS patient group.
Keywords: Iceland; eye diseases; genetics; hereditary; human genetics; population; retinitis pigmentosa.Icelandic Student Innovation Fund
Icelandic Association of the Visually Impaired
Richard P. Theodore and Dora Sigurjonsdottir Fund for improving scientific knowledge on blindnes
Changes in the incidence of invasive disease due to Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis during the COVID-19 pandemic in 26 countries and territories in the Invasive Respiratory Infection Surveillance Initiative: a prospective analysis of surveillance data.
Get PDFTo access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadBackground Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis, which are typically transmitted via respiratory droplets, are leading causes of invasive diseases, including bacteraemic pneumonia and meningitis, and of secondary infections subsequent to post-viral respiratory disease. The aim of this study was to investigate the incidence of invasive disease due to these pathogens during the early months of the COVID-19 pandemic.
Methods In this prospective analysis of surveillance data, laboratories in 26 countries and territories across six continents submitted data on cases of invasive disease due to S pneumoniae, H influenzae, and N meningitidis from Jan 1, 2018, to May, 31, 2020, as part of the Invasive Respiratory Infection Surveillance (IRIS) Initiative. Numbers of weekly cases in 2020 were compared with corresponding data for 2018 and 2019. Data for invasive disease due to Streptococcus agalactiae, a non-respiratory pathogen, were collected from nine laboratories for comparison. The stringency of COVID-19 containment measures was quantified using the Oxford COVID-19 Government Response Tracker. Changes in population movements were assessed using Google COVID-19 Community Mobility Reports. Interrupted time-series modelling quantified changes in the incidence of invasive disease due to S pneumoniae, H influenzae, and N meningitidis in 2020 relative to when containment measures were imposed.
Findings 27 laboratories from 26 countries and territories submitted data to the IRIS Initiative for S pneumoniae (62 837 total cases), 24 laboratories from 24 countries submitted data for H influenzae (7796 total cases), and 21 laboratories from 21 countries submitted data for N meningitidis (5877 total cases). All countries and territories had experienced a significant and sustained reduction in invasive diseases due to S pneumoniae, H influenzae, and N meningitidis in early 2020 (Jan 1 to May 31, 2020), coinciding with the introduction of COVID-19 containment measures in each country. By contrast, no significant changes in the incidence of invasive S agalactiae infections were observed. Similar trends were observed across most countries and territories despite differing stringency in COVID-19 control policies. The incidence of reported S pneumoniae infections decreased by 68% at 4 weeks (incidence rate ratio 0.32 [95% CI 0.27-0.37]) and 82% at 8 weeks (0.18 [0.14-0.23]) following the week in which significant changes in population movements were recorded.
Interpretation The introduction of COVID-19 containment policies and public information campaigns likely reduced transmission of S pneumoniae, H influenzae, and N meningitidis, leading to a significant reduction in life-threatening invasive diseases in many countries worldwide.Wellcome Trust
Robert Koch Institute (Germany)
Federal Ministry of Health (Germany)
Pfizer
Merck & Company
Health Protection Surveillance Centre (Ireland)
SpID-Net project (Ireland)
European Centre for Disease Prevention and Control (European Union)
Horizon 2020 (European Commission)
Ministry of Health (Poland)
National Programme of Antibiotic Protection (Poland)
Ministry of Science and Higher Education, Poland
Appeared in source as:Ministry of Science and Higher Education (Poland)
Agencia de Salut Publica de Catalunya (Spain)
Sant Joan de Deu Foundation (Spain)
Knut & Alice Wallenberg Foundation
Swedish Research Council
Region Stockholm (Sweden)
Federal Office of Public Health of Switzerland (Switzerland)
French Public Health Agency (France
Sequence variants in malignant hyperthermia genes in Iceland: classification and actionable findings in a population database.
Get PDFTo access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadMalignant hyperthermia (MH) susceptibility is a rare life-threatening disorder that occurs upon exposure to a triggering agent. MH is commonly due to protein-altering variants in RYR1 and CACNA1S. The American College of Medical Genetics and Genomics recommends that when pathogenic and likely pathogenic variants in RYR1 and CACNA1S are incidentally found, they should be reported to the carriers. The detection of actionable variants allows the avoidance of exposure to triggering agents during anesthesia. First, we report a 10-year-old Icelandic proband with a suspected MH event, harboring a heterozygous missense variant NM_000540.2:c.6710G>A r.(6710g>a) p.(Cys2237Tyr) in the RYR1 gene that is likely pathogenic. The variant is private to four individuals within a three-generation family and absent from 62,240 whole-genome sequenced (WGS) Icelanders. Haplotype sharing and WGS revealed that the variant occurred as a somatic mosaicism also present in germline of the proband's paternal grandmother. Second, using a set of 62,240 Icelanders with WGS, we assessed the carrier frequency of actionable pathogenic and likely pathogenic variants in RYR1 and CACNA1S. We observed 13 actionable variants in RYR1, based on ClinVar classifications, carried by 43 Icelanders, and no actionable variant in CACNA1S. One in 1450 Icelanders carries an actionable variant for MH. Extensive sequencing allows for better classification and precise dating of variants, and WGS of a large fraction of the population has led to incidental findings of actionable MH genotypes.deCODE Genetics/Amgen Inc
Cyclodextrin-based formulation of carbonic anhydrase inhibitors for ocular delivery - A review.
No full textTo access publisher's full text version of this article click on the hyperlink belowCarbonic anhydrase inhibitors (CAIs) are used as systemic and topical agents for lowering intraocular pressure (IOP) in patients with glaucoma. Owing to the wide distribution of CAs and their physiological functions in various tissues, systemic administration of CAIs may lead to unwanted side effects. Thus, exploration of drugs targeting the specific CA isoenzyme in ocular tissues and application of the same as topical eye drops would be desirable. However, the anatomical and physiological barriers of the eyes can limit drug availability at the site. The very low aqueous solubility of CAI agents can further hamper drug bioavailability, consequently resulting in insufficient therapeutic efficacy. Solubilization of drugs using cyclodextrin (CD) complexes can enhance both solubility and permeability of the drugs. The use of CD for such purposes and development and testing of topical CAI eye drops containing CD have been discussed in detail. Further, pharmaceutical nanotechnology platforms were discussed in terms of investigation of their IOP-lowering efficacies. Future prospects in drug discovery and the use of CD nanoparticles and CD-based nanocarriers to develop potential topical CAI formulations have also been described here.
Keywords: Carbonic anhydrase inhibitor; Cyclodextrin; Glaucoma; Intraocular pressure; Nanocarrier; Solubilization
When does fetal head rotation occur in spontaneous labor at term: results of an ultrasound-based longitudinal study in nulliparous women.
No full textTo access publisher's full text version of this article click on the hyperlink belowBackground: Improved information about the evolution of fetal head rotation during labor is required. Ultrasound methods have the potential to provide reliable new knowledge about fetal head position.
Objective: The aim of the study was to describe fetal head rotation in women in spontaneous labor at term using ultrasound longitudinally throughout the active phase.
Study design: This was a single center, prospective cohort study at Landspitali - The National University Hospital of Iceland, Reykjavík, Iceland, from January 2016 to April 2018. Nulliparous women with a single fetus in cephalic presentation and spontaneous labor onset at ≥37 weeks' gestation were eligible. Inclusion occurred when the active phase could be clinically established by labor ward staff. Cervical dilatation was clinically examined. Fetal head position and subsequent rotation were determined using both transabdominal and transperineal ultrasound. Occiput positions were marked on a clockface graph with 24 half-hour divisions and categorized into occiput anterior (≥10- and ≤2-o'clock positions), left occiput transverse (>2- and 8- and <10-o'clock positions). Head descent was measured with ultrasound as head-perineum distance and angle of progression. Clinical vaginal and ultrasound examinations were performed by separate examiners not revealing the results to each other.
Results: We followed the fetal head rotation relative to the initial position in the pelvis in 99 women, of whom 75 delivered spontaneously, 16 with instrumental assistance, and 8 needed cesarean delivery. At inclusion, the cervix was dilated 4 cm in 26 women, 5 cm in 30 women, and ≥6 cm in 43 women. Furthermore, 4 women were examined once, 93 women twice, 60 women 3 times, 47 women 4 times, 20 women 5 times, 15 women 6 times, and 3 women 8 times. Occiput posterior was the most frequent position at the first examination (52 of 99), but of those classified as posterior, most were at 4- or 8-o'clock position. Occiput posterior positions persisted in >50% of cases throughout the first stage of labor but were anterior in 53 of 80 women (66%) examined by and after full dilatation. The occiput position was anterior in 75% of cases at a head-perineum distance of ≤30 mm and in 73% of cases at an angle of progression of ≥125° (corresponding to a clinical station of +1). All initial occiput anterior (19), 77% of occiput posterior (40 of 52), and 93% of occiput transverse positions (26 of 28) were thereafter delivered in an occiput anterior position. In 6 cases, the fetal head had rotated over the 6-o'clock position from an occiput posterior or transverse position, resulting in a rotation of >180°. In addition, 6 of the 8 women ending with cesarean delivery had the fetus in occiput posterior position throughout the active phase of labor.
Conclusion: We investigated the rotation of the fetal head in the active phase of labor in nulliparous women in spontaneous labor at term, using ultrasound to provide accurate and objective results. The occiput posterior position was the most common fetal position throughout the active phase of the first stage of labor. Occiput anterior only became the most frequent position at full dilatation and after the head had descended below the midpelvic plane.
Keywords: active phase; angle of progression; cesarean delivery; fetal head position; head-perineum distance; progress of labor; transabdominal ultrasound; transperineal ultrasound.Icelandic Centre for Researc
Heart rate variability during wakefulness as a marker of obstructive sleep apnea severity.
No full textTo access publisher's full text version of this article click on the hyperlink belowStudy objectives: Patients with obstructive sleep apnea (OSA) exhibit heterogeneous heart rate variability (HRV) during wakefulness and sleep. We investigated the influence of OSA severity on HRV parameters during wakefulness in a large international clinical sample.
Methods: 1247 subjects (426 without OSA and 821 patients with OSA) were enrolled from the Sleep Apnea Global Interdisciplinary Consortium. HRV parameters were calculated during a 5-minute wakefulness period with spontaneous breathing prior to the sleep study, using time-domain, frequency-domain and nonlinear methods. Differences in HRV were evaluated among groups using analysis of covariance, controlling for relevant covariates.
Results: Patients with OSA showed significantly lower time-domain variations and less complexity of heartbeats compared to individuals without OSA. Those with severe OSA had remarkably reduced HRV compared to all other groups. Compared to non-OSA patients, those with severe OSA had lower HRV based on SDNN (adjusted mean: 37.4 vs. 46.2 ms; p < 0.0001), RMSSD (21.5 vs. 27.9 ms; p < 0.0001), ShanEn (1.83 vs. 2.01; p < 0.0001), and Forbword (36.7 vs. 33.0; p = 0.0001). While no differences were found in frequency-domain measures overall, among obese patients there was a shift to sympathetic dominance in severe OSA, with a higher LF/HF ratio compared to obese non-OSA patients (4.2 vs. 2.7; p = 0.009).
Conclusions: Time-domain and nonlinear HRV measures during wakefulness are associated with OSA severity, with severe patients having remarkably reduced and less complex HRV. Frequency-domain measures show a shift to sympathetic dominance only in obese OSA patients. Thus, HRV during wakefulness could provide additional information about cardiovascular physiology in OSA patients.
Clinical trial information: A Prospective Observational Cohort to Study the Genetics of Obstructive Sleep Apnea and Associated Co-Morbidities (German Clinical Trials Register - DKRS, DRKS00003966) https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00003966.
Keywords: autonomic nervous activity; frequency domain analysis; heart rate variability; nonlinear dynamic analysis; obstructive sleep apnea; time domain analysis; wakefulness.United States Department of Health & Human Services
National Institutes of Health (NIH) - USA
Appeared in source as:National Institutes of Health (NIH)
American Academy of Sleep Medicine Foundation (AASM)
Ministerio de Educacion, Cultura y Deport
Fertility preservation in boys: recent developments and new insights .
Get PDFTo access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadBackground: Infertility is an important side effect of treatments used for cancer and other non-malignant conditions in males. This may be due to the loss of spermatogonial stem cells (SSCs) and/or altered functionality of testicular somatic cells (e.g. Sertoli cells, Leydig cells). Whereas sperm cryopreservation is the first-line procedure to preserve fertility in post-pubertal males, this option does not exist for prepubertal boys. For patients unable to produce sperm and at high risk of losing their fertility, testicular tissue freezing is now proposed as an alternative experimental option to safeguard their fertility.
Objective and rationale: With this review, we aim to provide an update on clinical practices and experimental methods, as well as to describe patient management inclusion strategies used to preserve and restore the fertility of prepubertal boys at high risk of fertility loss.
Search methods: Based on the expertise of the participating centres and a literature search of the progress in clinical practices, patient management strategies and experimental methods used to preserve and restore the fertility of prepubertal boys at high risk of fertility loss were identified. In addition, a survey was conducted amongst European and North American centres/networks that have published papers on their testicular tissue banking activity.
Outcomes: Since the first publication on murine SSC transplantation in 1994, remarkable progress has been made towards clinical application: cryopreservation protocols for testicular tissue have been developed in animal models and are now offered to patients in clinics as a still experimental procedure. Transplantation methods have been adapted for human testis, and the efficiency and safety of the technique are being evaluated in mouse and primate models. However, important practical, medical and ethical issues must be resolved before fertility restoration can be applied in the clinic.Since the previous survey conducted in 2012, the implementation of testicular tissue cryopreservation as a means to preserve the fertility of prepubertal boys has increased. Data have been collected from 24 co-ordinating centres worldwide, which are actively offering testis tissue cryobanking to safeguard the future fertility of boys. More than 1033 young patients (age range 3 months to 18 years) have already undergone testicular tissue retrieval and storage for fertility preservation.
Limitations reasons for caution: The review does not include the data of all reproductive centres worldwide. Other centres might be offering testicular tissue cryopreservation. Therefore, the numbers might be not representative for the entire field in reproductive medicine and biology worldwide. The key ethical issue regarding fertility preservation in prepubertal boys remains the experimental nature of the intervention.
Wider implications: The revised procedures can be implemented by the multi-disciplinary teams offering and/or developing treatment strategies to preserve the fertility of prepubertal boys who have a high risk of fertility loss.
Study funding/competing interests: The work was funded by ESHRE. None of the authors has a conflict of interest.
Keywords: cryopreservation; fertility preservation; fertility restoration; in vitro spermatogenesis; prepubertal boys; spermatogonial stem cell; testicular tissue freezing; testis; transplantation.European Society of Human Reproduction and Embryology
UK Research & Innovation (UKRI)
Medical Research Council UK (MRC)
European Commission
Kom op tegen kanker (KOTK)
Netherlands Organization for Health Research and Development ZonMw
Belgian Fondation contre le cancer
Fonds de la Recherche Scientifiqu
SERS Imaging of Mesenchymal Stromal Cell Differentiation
No full textTo access publisher's full text version of this article click on the hyperlink belowUnderstanding the process of mesenchymal stromal cell (MSC) osteogenic differentiation is essential for a wide range of medical applications. However, these primary cells vary significantly from donor to donor, making it difficult to fully exploit their therapeutic potential. Although osteogenic differentiation has been studied extensively, there is still a shortage of standardized methods for the evaluation of the degree of differentiation. Here, we employ noninvasive surface-enhanced Raman scattering (SERS) for studying such cells, offering a better understanding of cellular processes in situ. We present the long-term differentiation of MSCs on biocompatible gold nanoisland SERS substrates, combining imaging of cells with spectroscopic detection of molecular species and chemical events occurring on the cellular membrane adjacent to the surface of the SERS substrate. We detect multiple signs of bone tissue formation, from an early stage to mature osteoblasts, without labeling. We show that the results correlate very well with classical differentiation-detecting assays, indicating that the SERS imaging technique alone is sufficient to study the progress of osteogenic differentiation of such cells, paving a way toward continuous label-free screening of live cells. © 2021 American Chemical Society.
Author keywords
extracellular matrix; hydroxyapatite; mesenchymal stromal cells; osteogenic differentiation; SERS substrates; stem cells; surface-enhanced Raman scattering (SERS)University of Iceland Research Fund
Landspitali University Hospital Research fun