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Background: The δ (delta) variant has spread rapidly worldwide and has become the predominant strain of SARS-CoV-2. We analyzed an outbreak caused by a vaccine breakthrough infection in a hospital with an active infection control program where 91.9% of healthcare workers were vaccinated. Methods: We investigated a SARS-CoV-2 outbreak between September 9 and October 2, 2021, in a referral teaching hospital in Korea. We retrospectively collected data on demographics, vaccination history, transmission, and clinical features of confirmed COVID-19 in patients, healthcare workers, and caregivers. Results: During the outbreak, 94 individuals tested positive for SARS-CoV-2 using reverse transcription-polymerase chain reaction (rtPCR) testing. Testing identified infections in 61 health care workers, 18 patients, and 15 caregivers, and 70 (74.5%) of 94 cases were vaccine breakthrough infections. We detected 3 superspreading events: in the hospital staff cafeteria and offices (n = 47 cases, 50%), the 8th floor of the main building (n = 22 cases, 23.4%), and the 7th floor in the maternal and child healthcare center (n = 12 cases, 12.8%). These superspreading events accounted for 81 (86.2%) of 94 transmissions (Fig. 1, 2). The median interval between completion of vaccination and COVID-19 infection was 117 days (range, 18–187). There was no significant difference in the mean Ct value of the RdRp/ORF1ab gene between fully vaccinated individuals (mean 20.87, SD±6.28) and unvaccinated individuals (mean 19.94, SD±5.37, P = .52) at the time of diagnosis. Among healthcare workers and caregivers, only 1 required oxygen supplementation. In contrast, among 18 patients, there were 4 fatal cases (22.2%), 3 of whom were unvaccinated (Table 1). Conclusions: Superspreading infection among fully vaccinated individuals occurred in an acute-care hospital while the δ (delta) variant was dominant. Given the potential for severe complications, as this outbreak demonstrated, preventive measures including adequate ventilation should be emphasized to minimize transmission in hospitals.
Accurate prognostication is important for patients and their families to prepare for the end of life. Objective Prognostic Score (OPS) is an easy-to-use tool that does not require the clinicians’ prediction of survival (CPS), whereas Palliative Prognostic Score (PaP) needs CPS. Thus, inexperienced clinicians may hesitate to use PaP. We aimed to evaluate the accuracy of OPS compared with PaP in inpatients in palliative care units (PCUs) in three East Asian countries.
This study was a secondary analysis of a cross-cultural, multicenter cohort study. We enrolled inpatients with far-advanced cancer in PCUs in Japan, Korea, and Taiwan from 2017 to 2018. We calculated the area under the receiver operating characteristics (AUROC) curve to compare the accuracy of OPS and PaP.
A total of 1,628 inpatients in 33 PCUs in Japan and Korea were analyzed. OPS and PaP were calculated in 71.7% of the Japanese patients and 80.0% of the Korean patients. In Taiwan, PaP was calculated for 81.6% of the patients. The AUROC for 3-week survival was 0.74 for OPS in Japan, 0.68 for OPS in Korea, 0.80 for PaP in Japan, and 0.73 for PaP in Korea. The AUROC for 30-day survival was 0.70 for OPS in Japan, 0.71 for OPS in Korea, 0.79 for PaP in Japan, and 0.74 for PaP in Korea.
Significance of results
Both OPS and PaP showed good performance in Japan and Korea. Compared with PaP, OPS could be more useful for inexperienced physicians who hesitate to estimate CPS.
Several studies on the treatment of coronavirus disease 2019 (COVID-19) are being conducted, and various drugs are being tried; however, the results have not been uniform. Steroids have been widely used in the treatment of COVID-19, but their effects are controversial. As immunosuppressive and anti-inflammatory agents, steroids are considered to reduce lung damage by regulating various inflammatory responses. We report a case of severe acute respiratory syndrome coronavirus-2 pneumonia manifesting as a cryptogenic organizing pneumonia-like reaction and discuss its treatment, clinical course, and favorable outcomes after steroid administration.
A number of microorganisms were hypothesised as an aetiology of the Kawasaki disease. Unfortunately, no specific agent that provides reproducible evidence has yet been reported. We report two cases of extremely rare Kawasaki disease with tsutsugamushi disease. These case reports suggest that Kawasaki disease can rarely occur concurrently or immediately after a rickettsial illness such as tsutsugamushi disease.
A life-threatening cardiopulmonary resuscitation (CPR)-related injury can cause recurrent arrest after return of circulation. Such injuries are difficult to identify during resuscitation, and their contribution to failed resuscitation can be missed given the limitations of conventional CPR. Extracorporeal cardiopulmonary resuscitation (ECPR), increasingly being considered for selected patients with potentially reversible etiology of arrest, may identify previously occult CPR-related injuries by restoring arterial pressure and flow. Herein, we describe two cases of severe CPR-related injuries contributing to recurrent arrest. Each case had ECPR implemented within 60 minutes of the start of CPR. After the presumed cardiac etiology had been addressed with percutaneous coronary intervention, life-threatening cardiovascular injuries with recurrent arrest were noted, and resuscitative thoracotomy was performed under ECPR. One patient survived to hospital discharge.
ECPR may provide an opportunity to identify and correct severe resuscitation-related injuries causing recurrent arrest. Chest compression depth >6 cm, especially in older women, may contribute to these injuries.
The HoDoo English game was developed to take advantage of the benefits attributed to on-line games while teaching English to native Korean speakers. We expected to see that the improvements in the subjects’ English language abilities after playing the HoDoo English game would be associated with increased brain functional connectivity in the areas of the brain involved in the language production (Broca’s area) and the understanding (Wernicke’s area) networks. Twelve children, aged nine and ten, were asked to play the on-line English education game for 50 minutes per day, five days per week for twelve weeks. At baseline, and again at the end of twelve weeks of game play, each child’s English language ability was assessed and a functional magnetic resonance imaging (fMRI) scan was conducted. The on-line English education game play effectively improved English language skills, especially in terms of non-verbal pragmatic skills. Following twelve weeks of on-line English education game play, the children showed positive connectivity between Broca’s area and the left frontal cortex as well as between Wernicke’s area and the left parahippocampal gyrus and the right medial frontal gyrus. Changes in pragmatic scores were positively correlated with average peak brain activity in the left parahippocampal gyrus. To the best of our knowledge, this is the first study to report an improvement in English ability and changes in brain activity within language areas after on-line language education game play.
In Korea, patients with terminal cancer are often caught out of the loop in end-of-life (EoL) care discussions. Healthcare professionals also have difficulty engaging in such communication in a variety of healthcare contexts. Therefore, the objective of our study was to develop a communication model for EoL care decision making compatible with the clinical environment in Korea.
Using focus-group interview methodology, participants included eight doctors and five nurses who provide EoL care for terminal cancer patients in acute hospital settings or hospice care facilities in various provinces of Korea.
Five themes emerged regarding EoL care discussion, which included: (1) timing, (2) responsible professionals, (3) disclosure of bad news, (4) content areas of EoL care discussion, and (5) implementing strategies for EoL care discussions. These themes were based on development of a communication algorithm for EoL discussion among patients with terminal cancer. A structural communication step for delivery of a terminal prognosis was specified at the phase of disclosure of bad news: beginning with determination of a patient's decision-making capability, followed by a patient's perception of his/her condition, a patient's wish to know, family dynamics, and a patient's and/or family's readiness for EoL discussions.
Significance of Results:
The proposed context-oriented communication algorithm could provide a helpful guideline for EoL communication and, accordingly, facilitate meaningful improvements in EoL care in Korean clinical practice. The feasibility of this algorithm has not yet been determined, and its validation in a larger sample of patients with terminal cancers, using a quantitative research methodology, is a priority of research.
The present study was performed to investigate whether breast-feeding is associated with early pubertal development among children 7–9 years old in Korea.
Children were divided into those who did and did not receive breast-feeding for 6 months or longer in accordance with the recommendations of the WHO. Pubertal status was determined by clinical examination using Tanner staging.
Prospective observational study.
We conducted a follow-up study of children aged 7–9 years in 2011 who had taken part in the Ewha Birth & Growth Cohort study.
Fifty (22·8 %) of the total of 219 children were in early puberty, with the proportion being slightly higher for girls (24·1 %) than boys (21·4 %). Children who had entered early puberty were taller, weighed more and had a higher concentration of insulin-like growth factor 1. Moreover, the change in weight Z-score from birth to follow-up was significantly lower in children who were breast-fed than in those who were not (weight Z-score change: 0·32 (sd 1·59) v. 0·77 (sd 1·61), respectively, P=0·04). Comparison of breast-feeding by puberty status indicated a preventive association with early puberty in children who were breast-fed for 6 months or longer (OR=0·37; 95 % CI 0·18, 0·74). This association remained significant after adjustment for relevant covariates.
These results demonstrate a beneficial association between breast-feeding and early pubertal development, especially in those breast-fed for 6 months or longer. The study suggests that interventions would need to start early in life to prevent early pubertal development.
Octamer-binding transcription factor 4 (Oct4) is a critical molecule for the self-renewal and pluripotency of embryonic stem cells. Recent reports have shown that Oct4 also controls cell-cycle progression and enhances the proliferation of various types of cells. As the high proliferation of donor fibroblasts is critical to the production of transgenic pigs, using the somatic cell nuclear transfer technique, we analysed the effect of Oct4 overexpression on the proliferation of porcine fibroblasts and embryos. Porcine endogenous Oct4 cDNA was cloned, sequenced and inserted into an expression vector. The vector was transfected into porcine fibroblasts, and a stable Oct4-overexpressed cell line was established by antibiotic selection. Oct4 expression was validated by the immunostaining of Oct4. Cell morphology was changed to sharp, and both proliferation and migration abilities were enhanced in Oct4-overexpressed cells. Real-time RT-PCR results showed that p16, Bcl2 and Myc were upregulated in Oct4-overexpressed cells. Somatic cell nuclear transfer was performed using Oct4-overexpressed cells, and the development of Oct4 embryos was compared with that of wild-type cloned embryos. The cleavage and blastocyst formation rates were improved in the Oct4 embryos. Interestingly, blastocyst formation of the Oct4 embryos was observed as early as day 5 in culture, while blastocysts were observed from day 6 in wild-type cloned embryos. In conclusion, the overexpression of Oct4 enhanced the proliferation of both porcine fibroblasts and embryos.
The microstructural analysis of the dehydrogenation products of the Ca(BH4)2–MgH2 composite was performed using transmission electron microscopy. It was found that nanocrystalline CaB6 crystallites formed as a dehydrogenation product throughout the areas where the signals of Ca and Mg were simultaneously detected, in addition to relatively coarse Mg crystallites. The uniform distribution of the nanocrystalline CaB6 crystallites appears to play a key role in the rehydrogenation of the dehydrogenation products, which implies that microstructure is a crucial factor determining the reversibility of reactive hydride composites.
Adiponectin has been associated with insulin resistance and type 2 diabetes mellitus and possibly fetal growth. Our aim was to assess the association between the single nucleotide polymorphisms (SNPs) of the adiponectin gene (ADIPOQ) and the birth sizes. We investigated four SNPs of ADIPOQ (rs182052, rs2241766, rs1501299, and rs266729) and birth height and weight in 237 healthy full-term neonates. The neonates with the rs182052 G allele had a greater birth weight (p = .043 in the dominant model) and a higher ponderal index (p = .028 in the additive model). The rs2241766 G allele was associated with a greater birth weight (p = .016 in the recessive model). In a logistic regression analysis, the homozygotes for the rs182052 G allele and those for the rs2241766 G allele showed a significant association with a greater birth weight above 90 percentile (OR 2.75, 95% CI 1.13–6.70 and OR 5.15, 95% CI 1.66–15.99, respectively). In conclusion, we found an association between rs182052 and rs2241766 and birth weight and ponderal index among healthy neonates and suggested that adiponectin might have some roles in fetal growth.
The presence of glutamine (Gln) in in vitro maturation (IVM) and in vitro culture (IVC) medium is a more potent factor for improving porcine oocyte and embryo development than other amino acids. However Gln is inherently unstable and spontaneously breaks down into ammonia, and therefore interferes with proper development. To avoid this adverse effect, Gln was replaced in the present study with its stable dipeptide derivative alanyl-glutamine (Ala-Gln) and the effects of this replacement on porcine IVM and IVC were evaluated. Replacement of Gln with Ala-Gln during IVM did not improve nuclear maturation, however numbers of early cleaved embryos were significantly increased after activation. Blastocyst formation rates were also significantly improved by using Ala-Gln during IVM. Replacement of Gln with Ala-Gln during IVC significantly increased total cell numbers in blastocysts. Blastocyst formation rate was also significantly higher when Ala-Gln was used in both IVM and IVC. In conclusion, the use of Ala-Gln rather than Gln gives better results for development in both porcine IVM and IVC.
On June 29, 1789, Zephaniah Turner of Charles County, Maryland, wrote to President George Washington and observed:
Our Laws are too Numerous. Is it not possible that an alteration might take place for the benefit of the public?…Could it not be possible to curtail the Number of Lawyers in the different States? Suppose each State was to have but Two Lawyers to be paid liberally…[and] where a real dispute subsisted between Plaintiff and Defendant a reference [to arbitration] should be proposed, and arbitrators [be] indifferently chosen by both parties…whose determination shall be final.
In this study, we investigated the effect of two oxygen concentrations (5 and 20%) during in vitro maturation (IVM) and during in vitro culture (IVC) on porcine embryo development and analysed differences in gene expression between cumulus–oocyte complexes matured under 5 or 20% oxygen and the resulting blastocysts cultured under 5% or 20% oxygen following parthenogenetic activation. There was no significant difference in oocyte maturation rate. However, the numbers of resulting blastocysts were significantly increased in the 5% IVC group compared with the 20% IVC group. Moreover, the M20C5 treatment group (23.01%) supported greater blastocyst development compared with the M5C5 (14.32%), M5C20 (10.30%), and M20C20 (17.88%) groups. However, total cell numbers were not significantly different among groups. According to mRNA abundance data of multiple genes, each treatment altered the expression of genes in different patterns. GLUT1, G6PD and LDHA were up-regulated in cumulus cells that had been matured in low oxygen, suggesting a higher glucose uptake and an increase in anaerobic glycolysis, whereas cyclin B1 (CCNB) and MnSOD (Mn-superoxide dismutase) were upregulated in cumulus cells that had been matured in high oxygen, which suggests a higher activity of mitosis-promoting factor and antioxidant response. In spite of these differential effects on cumulus cells, oocytes could mature normally regardless of different oxygen concentrations. Therefore, it can be concluded that high oxygen concentration during in vitro maturation and low oxygen during in vitro culture may alter the expression of multiple genes related to oocyte competence and significantly improves embryo development (p < 0.05) but not blastocyst quality.
The oocyte is known from recent studies in the mouse, cow, sheep and human to be a central regulator of follicular cell function. However, in the pig, little information is known about the regulation of cumulus expansion by oocyte-secreted factors and oocyte quality. We investigated the possible effects of oocyte-secreted factors during in vitro maturation on cumulus expansion and on porcine oocytes as judged by subsequent embryonic development after parthenogenetic activation. Cumulus–oocyte complexes (COC) from antral follicles of pig ovaries collected from a local abattoir were divided into control and treatment groups and were cultured in tissue culture medium 199 supplemented with follicle-stimulating hormone. Treatment groups consisted of increasing numbers of denuded oocytes (DO) co-cultured with COC (at ratios of COC to DO of 1:1, 1:2, 1:3, 1:4 and 1:5). After incubation for 44 h, cumulus expansion and maturation rates were assessed and oocytes were activated parthenogenetically. Cumulus expansion in the 1 COC:4 DO and 1 COC:5 DO groups was low and altered because full dispersion of the outer layer did not occur. Cell viability was not affected, as measured by the automated cell counter, but scanning electron microscopy revealed only a scanty extracellular matrix. Blastocyst rate was significantly higher in the 1 COC:4 DO (34.4%) and in the 1 COC:5 DO (34.9%) groups (p < 0.05) when compared with other groups. Maturation rate, cleavage rate and total cell number showed no significant difference between control and treatment groups. Amplification by reverse transcription polymerase chain reaction (RT-PCR) showed up-regulation of growth differentiation factor 9 (GDF9) in the cumulus cells in the 1 COC:4 DO group at 44 h. We conclude that denuded porcine oocytes could improve the maturation of COC as evidenced by increased blastocyst development in the 1 COC:4 DO, even though cumulus expansion was poor. This improvement could be a result of the GDF9 up-regulation.
In non-human primates, it is difficult to collect sufficient numbers of oocytes for producing identical embryos by somatic cell nuclear transfer (SCNT). Because of this factor, inter-species SCNT (iSCNT) using heterospecific oocytes is an attractive alternative approach. The objective of this study was to produce iSCNT-derived blastocysts using enucleated cow (Bos taurus) metaphase II oocytes and adult rhesus monkey (Macaca mulatta) fibroblasts. Ear skin tissue from a 6-year-old male rhesus monkey was collected by biopsy and fibroblasts were isolated. Immature cumulus–oocyte complexes from cow ovaries were collected and matured in vitro in Medium 199. The enucleated oocytes were reconstructed with rhesus monkey fibroblasts and iSCNT embryos were cultured in modified synthetic oviduct fluid in an atmosphere of 5–5.5% CO2 under various conditions (37–39 °C and 5–20% O2) to examine the effects of in vitro culture conditions. Most embryos were arrested at the 8- or 16-cell stage and only three blastocysts were derived in this way using iSCNT from a total of 1153 cultured activated embryos (0.26% production rate). Two of the three blastocysts were used for counting nuclear numbers using bisbenzimide staining, which were 51 and 24. The other iSCNT-derived blastocyst was used to analyse mitochondrial DNA (mtDNA) by PCR, and both rhesus monkey and cow mtDNA were detected. Although the development rate was extremely low, this study established that iSCNT using two phylogenetically distant species, including a primate, could produce blastocysts. With improvements in the development rate, it may be possible to produce rhesus monkey iSCNT-derived embryonic stem cell lines for studies on primate nucleus and cow mitochondria interaction mechanisms.
Treatment with 6-dimethylaminopurine (6-DMAP) or demecolcine (DE) for several (at least 2) hours after artificial activation is known to improve in vitro development of porcine embryos. However, several reports have also shown that treatments with these chemicals induce apoptosis. The aim of this study was to find out whether short-term treatment with 6-DMAP and DE combined with electrical or thimerosal/dithiothreitol (Thi/DTT) activation had a beneficial effect on development of parthenogenetically activated porcine oocytes. We additionally treated embryos with 6-DMAP (2 mM) and/or DE (0.4 μg/ml) for a short time (40 min) after an electrical pulse (EP) or Thi/DTT. As a result, short-term treatment with 6-DMAP and DE successfully induced development of electrically or Thi/DTT-activated porcine parthenogenetic embryos with no significant difference in cleavage rate, blastocyst formation rate and total cell number compared with long-term treatment. To find optimal activation protocol, cleavage rate, blastocyst formation rate and total cell number were compared between EP and Thi/DTT treatments. Thi/DTT + 6-DMAP + DE showed significantly higher blastocyst formation rate (36.1 ± 3.5%) and total cell number (46.9 ± 1.0) than other groups (EP + 6-DMAP + DE, EP + Thi/DTT + 6-DMAP + DE: 23.3 ± 3.0%, 42.2 ± 1.1 and 17.2 ± 2.7%, 36.7 ± 1.5, respectively). In conclusion, this study demonstrates that short-term treatment with 6-DMAP and DE is as effective as the standard long-term treatment and Thi/DTT + 6-DMAP + DE exerts a synergistic effect.
The prevalence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains causing bloodstream infection (BSI) has not been studied in Korea.
We sought to determine the prevalence of CA-MRSA strains among isolates recovered from patients with MRSA BSIs and to explore epidemiological changes in Korea. We also sought to evaluate clinical characteristics relevant to the development of healthcare-associated BSIs.
We prospectively collected consecutive MRSA isolates from patients with BSI at 4 hospitals from July 1 through November 30, 2007, and we also included MRSA isolates recovered from culture of blood samples collected during a previous year (October 1, 2004 through September 30, 2005) at a different hospital. Molecular typing studies were performed, including pulsed-field gel electrophoresis (PFGE), multilocus sequence typing, Staphylococcus protein A (spa) typing, and staphylococcal cassette chromosome mec (SCCmec) typing. We compared the clinical characteristics and outcomes of patients with healthcare-associated BSI due to CA-MRSA strains with those of patients with healthcare-associated BSI due to healthcare-associated MRSA (HA-MRSA) strains.
There were 76 cases of MRSA BSI, of which 4 (5.3%) were community-associated and 72 (94.7%) were healthcare-associated. Among the 72 HA-MRSA BSIs, 18 (25%) were community onset, and 54 (75%) were hospital onset. PFGE type D-ST72–spa B-SCCmec type IVA MRSA, the predominant genotype of CA-MRSA in Korea, accounted for 19 (25%) of all 76 MRSA BSIs, including 17 (23.6%) of 72 HA-MRSA BSIs and 11 (20.8%) of 53 hospital-onset HA-MRSA BSIs. Patients with healthcare-associated BSIs due to CA-MRSA strains carrying SCCmec type IVA tended to have fewer healthcare-associated risk factors, compared with patients with healthcare-associated BSIs due to HA-MRSA strains carrying other SCCmec types. The presence of a central venous catheter or other invasive device was the only independent factor differentiating patients infected with hospital-associated genotype strains from patients infected with other strains. Clinical outcomes were similar between both groups.
CA-MRSA strains are emerging as a major cause of BSI in healthcare settings in Korea. This changing epidemiology of MRSA poses a challenge to public health and infection control in hospital settings.
To describe the incidence of recovery of both vancomycin-resistant enterococci (VRE) and methicillin-resistant Staphylococcus aureus (MRSA) from culture of a single clinical specimen, to describe the clinical characteristics of patients from whom these specimens were recovered, and to identify the risk factors of these patients.
A retrospective cohort and case-control study.
A tertiary care university hospital and referral center in Seoul, Korea.
We identified 61 case patients for whom a single clinical specimen yielded both VRE and MRSA on culture, and 122 control patients for whom any clinical specimen yielded only VRE on culture. The control patients were selected by matching 2 :1 with the case patients for age, sex, and first date of sampling that led to isolation of VRE or both VRE and MRSA among 1,536 VRE-colonized patients from January 1, 2003, through December 31, 2006. To identify patient risk factors for the recovery of both VRE and MRSA in a single clinical specimen, we performed univariate comparisons between the 2 groups and then multivariate logistic regression analysis.
The incidence of recovery of both VRE and MRSA from culture of a single clinical specimen was 3.97% (for 61 of 1,536 VRE-colonized patients) over 4 years. Among these 82 single clinical specimens, the most common type was wound specimens (26.8%), followed by lower respiratory tract specimens (18.3%), urine specimens (17.1%), and catheter tips (15.9%). Of the 61 case patients, 14 (23.0%) had 2 or more single clinical specimens that yielded both VRE and MRSA on culture, and the longest interval from the first sampling that yielded both organisms to the last sampling that yielded both was 174 days. Independent patient risk factors for the presence of both VRE and MRSA in a single clinical specimen were chronic renal disease (odds ratio [OR], 7.00; P = .012), urinary catheterization (OR, 3.36; P = .026), and longer total cumulative duration of hospital stay within the previous year (OR, 1.03; P < .001).
We confirmed that the recovery of VRE and MRSA from a single clinical specimen occurs continually. Because prolonged cell-to-cell contact can facilitate transfer of vanA, close observation and surveillance for vancomycin-resistant S. aureus, especially among patients with risk factors for the recovery of both VRE and MRSA from a single clinical specimen, should be continued.