Discover the most talked about and latest scientific content & concepts.

Journal: Journal of Korean medical science


Deletion and duplication of the -3.7-Mb region in 17p11.2 result in two reciprocal syndrome, Smith-Magenis syndrome and Potocki-Lupski syndrome. Smith-Magenis syndrome is a well-known developmental disorder. Potocki-Lupski syndrome has recently been recognized as a microduplication syndrome that is a reciprocal disease of Smith-Magenis syndrome. In this paper, we report on the clinical and cytogenetic features of two Korean patients with Smith-Magenis syndrome and Potocki-Lupski syndrome. Patient 1 (Smith-Magenis syndrome) was a 2.9-yr-old boy who showed mild dysmorphic features, aggressive behavioral problems, and developmental delay. Patient 2 (Potocki-Lupski syndrome), a 17-yr-old boy, had only intellectual disabilities and language developmental delay. We used array comparative genomic hybridization (array CGH) and found a 2.6 Mb-sized deletion and a reciprocal 2.1 Mb-sized duplication involving the 17p11.2. These regions overlapped in a 2.1 Mb size containing 11 common genes, including RAI1 and SREBF.

Concepts: DNA, Genetics, Copy number variation, Genome, Syndromes, Down syndrome, Array comparative genomic hybridization, Comparative genomic hybridization


The Journal Impact Factor (JIF) is a single citation metric, which is widely employed for ranking journals and choosing target journals, but is also misused as the proxy of the quality of individual articles and academic achievements of authors. This article analyzes Scopus-based publication activity on the JIF and overviews some of the numerous misuses of the JIF, global initiatives to overcome the ‘obsession’ with impact factors, and emerging strategies to revise the concept of the scholarly impact. The growing number of articles on the JIF, most of which are in English, reflects interest of experts in journal editing and scientometrics toward its uses, misuses, and options to overcome related problems. Solely displaying values of the JIFs on the journal websites is criticized by experts as these average metrics do not reflect skewness of citation distribution of individual articles. Emerging strategies suggest to complement the JIFs with citation plots and alternative metrics, reflecting uses of individual articles in terms of downloads and distribution of related information through social media and networking platforms. It is also proposed to revise the original formula of the JIF calculation and embrace the concept of the impact and importance of individual articles. The latter is largely dependent on ethical soundness of the journal instructions, proper editing and structuring of articles, efforts to promote related information through social media, and endorsements of professional societies.

Concepts: Academic publishing, Nature, Impact factor, Bibliometrics, Eugene Garfield


The objective of this study was to establish the efficacy and safety of procalcitonin (PCT)-guided antibiotic discontinuation in critically ill patients with sepsis in a country with a high prevalence of antimicrobial resistance and a national health insurance system.


Recently, injectable dermal fillers have become important alternatives to surgical procedures for the correction of facial wrinkles. Bovine collagen is the first approved material for filler injection, and several studies have shown its efficacy. However, the risk of developing an allergic reaction and xenogenic transmission of bovine spongiform encephalopathy remain among its disadvantages. In this randomized, double-blinded, split-face study, we compared the efficacy and safety of a porcine collagen filler (TheraFill®) with that of a bovine collagen filler (KOKEN®) for nasolabial fold correction. A total of sixty one patients with mild to severe nasolabial fold were randomized to receive TheraFill® and KOKEN® on contralateral sides of the face. During the 12-month follow-up period, improvement in the Wrinkle-Severity Rating Scale score was slightly higher in TheraFill® group than KOKEN® group, although the difference was not statistically significant. No serious adverse reactions were observed and both materials were tolerable in most cases. In conclusion, the long-term effect of TheraFill® on nasolabial fold correction was comparable to that of KOKEN®, and it may be a good alternative to bovine collagen filler.

Concepts: Surgery, Statistical significance, Allergy, Face, Transmissible spongiform encephalopathy, Bovine spongiform encephalopathy, Injection, Nasolabial fold


This article introduces predatory publishers in the context of biomedical sciences research. It describes the characteristics of predatory publishers, including spamming and using fake metrics, and it describes the problems they cause for science and universities. Predatory journals often fail to properly manage peer review, allowing pseudo-science to be published dressed up as authentic science. Academic evaluation is also affected, as some researchers take advantage of the quick, easy, and cheap publishing predatory journals provide. By understanding how predatory publishers operate, researchers can avoid becoming victimized by them.

Concepts: Scientific method, Academic publishing, Science, Research, Medical research, Peer review, Publishing, Biomedical scientist


We conducted a meta-analysis to investigate the efficacy of ginseng supplements on fatigue reduction and physical performance enhancement as reported by randomized controlled trials (RCTs). RCTs that investigated the efficacy of ginseng supplements on fatigue reduction and physical performance enhancement compared with placebos were included. The main outcome measures were fatigue reduction and physical performance enhancement. Out of 155 articles meeting initial criteria, 12 RCTs involving 630 participants (311 participants in the intervention group and 319 participants in the placebo group) were included in the final analysis. In the fixed-effect meta-analysis of four RCTs, there was a statistically significant efficacy of ginseng supplements on fatigue reduction (standardized mean difference, SMD = 0.34; 95% confidence interval [CI] = 0.16 to 0.52). However, ginseng supplements were not associated with physical performance enhancement in the fixed-effect meta-analysis of eight RCTs (SMD = -0.01; 95% CI = -0.29 to 0.27). We found that there was insufficient clinical evidence to support the use of ginseng supplements on reducing fatigue and enhancing physical performance because only few RCTs with a small sample size have been published so far. Further lager RCTs are required to confirm the efficacy of ginseng supplements on fatigue reduction.

Concepts: Clinical trial, Statistics, Sample size, Evidence-based medicine, Randomized controlled trial, Placebo, Confidence interval, Statistical hypothesis testing


We investigated the association between breastfeeding and cognitive development in infants during their first 3 years. The present study was a part of the Mothers' and Children’s Environmental Health (MOCEH) study, which was a multi-center birth cohort project in Korea that began in 2006. A total of 697 infants were tested at age 12, 24, and 36 months using the Korean version of the Bayley Scales of Infant Development II (K-BSID-II). The use and duration of breastfeeding and formula feeding were measured. The relationship between breastfeeding and the mental development index (MDI) score was analyzed by multiple linear regression analysis. The results indicated a positive correlation between breastfeeding duration and MDI score. After adjusting for covariates, infants who were breastfed for ≥ 9 months had significantly better cognitive development than those who had not been breastfed. These results suggest that the longer duration of breastfeeding improves cognitive development in infants.

Concepts: Regression analysis, Linear regression, Infant, Econometrics, Breastfeeding, Multivariate adaptive regression splines, Ordinary least squares, Child development


The change of compressing personnel will inevitably accompany hands off time when cardiopulmonary resuscitation (CPR) is performed by two or more rescuers. The present study assessed whether changing compression by a second rescuer located on the opposite side (OS) of the first rescuer can reduce hands-off time compared to CPR on the same side (SS) when CPR is performed by two rescuers. The scenario of this randomized, controlled, parallel simulation study was compression-only CPR by two laypersons in a pre-hospital situation. Considering sex ratio, 64 participants were matched up in 32 teams equally divided into two gender groups, i.e. , homogenous or heterogeneous. Each team was finally allocated to one of two study groups according to the position of changing compression (SS or OS). Every team performed chest compression for 8 min and 10 sec, with chest compression changed every 2 min. The primary endpoint was cumulative hands-off time. Cumulative hands-off time of the SS group was about 2 sec longer than the OS group, and was significant (6.6 ± 2.6 sec vs. 4.5 ± 1.5 sec, P = 0.005). The range of hands off time of the SS group was wider than for the OS group. The mean hands-off times of each rescuer turn significantly shortened with increasing number of turns (P = 0.005). A subgroup analysis in which cumulative hands-off time was divided into three subgroups in 5-sec intervals revealed that about 70% of the SS group was included in subgroups with delayed hands-off time ≥ 5 sec, with only 25% of the OS group included in these subgroups (P = 0.033). Changing compression at the OS of each rescuer reduced hands-off time compared to the SS in prehospital hands-only CPR provided by two bystanders.

Concepts: Cardiopulmonary resuscitation, Emergency medical services, Defibrillation


We performed a nationwide epidemiological study to evaluate the prevalence and characteristics of nocturnal enuresis (NE) in Korean adolescents and adults. A questionnaire was sent via e-mail to 51,073 people aged 16-40 yr by stratified sampling according to age, sex, and region among a 200,000 internet survey panel pool. The questionnaire included following information; presence or absence of NE, frequency of NE, possible risk factors for NE, self-esteem scale score and depression score results, and measures for the treatment of NE. Among the 2,117 responders, 54 (2.6%) had NE (≥1 enuretic episode within 6 months). Of 54 bedwetters, 9.3% wet ≥1 night per week and 20.5% wet ≥1 per month. The prevalence rates remained relatively stable with no apparent trend of reduction with age. The presence of sleep disturbance, family history, urgency, or urge incontinence increased the probability of NE episode significantly. The self-esteem score was lower (P=0.053) and the depression scale score was higher (P=0.003) in bedwetters compared with non-bedwetters. Overall 2.6% of Korean aged 16-40 yr have NE. The higher rate of urgency and urge incontinence in adolescent and adult enuretics suggests that bladder function has an important role in adolescent and adult NE.

Concepts: Epidemiology, Sampling, Biology, Urology, Urinary incontinence, Sleep, Stratified sampling, Nocturnal enuresis


To investigate the influence of nocturnal ambient light on visual function and ocular fatigue.