461 research outputs found
The Combination of Soft Sets and N-Structures with Applications
Using the notions of soft sets and N-structures, N-soft set theory is introduced. We apply it to both a decision making problem and a BCK/BCI algebra
Quasi-valuation maps based on positive implicative ideals in BCK-algebras
The notion of PI-quasi-valuation maps of a BCK-algebra is introduced, and related properties are investigated. The relationship between an I-quasi-valuation map and a PI-quasivaluation map is examined. Conditions for an I-quasi-valuation map to be a PI-quasi-valuation map are provided, and conditions for a real-valued function on a BCK-algebra to be a quasi-valuation map based on a positive implicative ideal are founded. The extension property for a PI-quasi-valuation map is established
Mind bomb 1 in the lymphopoietic niches is essential for T and marginal zone B cell development
Notch signaling regulates lineage decisions at multiple stages of lymphocyte development, and Notch activation requires the endocytosis of Notch ligands in the signal-sending cells. Four E3 ubiquitin ligases, Mind bomb (Mib) 1, Mib2, Neuralized (Neur) 1, and Neur2, regulate the Notch ligands to activate Notch signaling, but their roles in lymphocyte development have not been defined. We show that Mib1 regulates T and marginal zone B (MZB) cell development in the lymphopoietic niches. Inactivation of the Mib1 gene, but not the other E3 ligases, Mib2, Neur1, and Neur2, abrogated T and MZB cell development. Reciprocal bone marrow (BM) transplantation experiments revealed that Mib1 in the thymic and splenic niches is essential for T and MZB cell development. Interestingly, when BM cells from transgenic Notch reporter mice were transplanted into Mib1-null mice, the Notch signaling was abolished in the double-negative thymocytes. In addition, the endocytosis of Dll1 was impaired in the Mib1-null microenvironment. Moreover, the block in T cell development and the failure of Dll1 endocytosis were also observed in coculture system by Mib1 knockdown. Our study reveals that Mib1 is the essential E3 ligase in T and MZB cell development, through the regulation of Notch ligands in the thymic and splenic microenvironments
Simultaneous Total Occlusion of Multiple Distal Coronary Arteries in Acute Myocardial Infarction
Simultaneous multiple coronary artery thrombosis is a rare finding in ST segment elevation myocardial infarction (STEMI). We report a case of myocardial infarction with multiple ST segment elevation on the electrocardiography and total occlusions of the distal left anterior descending artery (dLAD), as well as of the second and third obtuse marginal artery on emergency coronary angiography. Thrombus aspiration was performed at dLAD and systemic glycoprotein IIb/IIIa inhibitor was used successfully. In patients with STEMI, multiple coronary thromboses are unusual and associated with patient fatality. However, assertive thrombus aspiration and antiplatelet therapy could be effective in STEMI patients with multiple distal coronary artery occlusions
Effect of subconjunctivally injected, liposome-bound, low-molecular-weight heparin on the absorption rate of subconjunctival hemorrhage in rabbits
PURPOSE: To investigate the effect of subconjunctival injection of liposome-bound, low-molecular-weight heparin (LMWH) on the absorption rate of subconjunctival hemorrhages. METHODS: Subconjunctival hemorrhages were induced in both eyes of 30 rabbits by the subconjunctival injection of 0.1 mL of autologous blood from auricular marginal veins. After 8 hours, randomized subconjunctival injections of one of three materials were made: 5 IU/mL liposome-bound LMWH (0.1 mL) in 18 eyes (group A), only liposomes (0.1 mL) in 14 eyes (group B), the free form of LMWH (5 IU/mL, 0.1 mL) in 14 eyes (group C), or no injection in 14 eyes (group D). Subconjunctival hemorrhages were photographed with a digital camera at 8, 24, 48, 72, 96, and 120 hours after induction of subconjunctival hemorrhages, sized with an image analyzer, and compared between groups. RESULTS: Subconjunctival hemorrhages were absorbed faster in group A (liposome-bound LMWH injected) than in with group B (liposome injected). Comparison of groups A and C (free LMWH injected) showed statistical differences in the absorption rates at 96 and 120 hours except at 24, 48, and 72 hours. The mean elapsed time for the complete resorption of subconjunctival hemorrhages was shortest in group A among four groups, whereas group B and the control showed no significant differences. The ocular and systemic absorption of LMWH were significantly lower after injection of the liposome-bound than the free form. CONCLUSIONS: The subconjunctival injection of liposome-bound LMWH appears to enhance subconjunctival hemorrhage absorption in rabbits
High frequencies of Y-chromosome haplogroup O2b-SRY465 lineages in Korea: a genetic perspective on the peopling of Korea
<p>Abstract</p> <p>Background</p> <p>Koreans are generally considered a Northeast Asian group, thought to be related to Altaic-language-speaking populations. However, recent findings have indicated that the peopling of Korea might have been more complex, involving dual origins from both southern and northern parts of East Asia. To understand the male lineage history of Korea, more data from informative genetic markers from Korea and its surrounding regions are necessary. In this study, 25 Y-chromosome single nucleotide polymorphism markers and 17 Y-chromosome short tandem repeat (Y-STR) loci were genotyped in 1,108 males from several populations in East Asia.</p> <p>Results</p> <p>In general, we found East Asian populations to be characterized by male haplogroup homogeneity, showing major Y-chromosomal expansions of haplogroup O-M175 lineages. Interestingly, a high frequency (31.4%) of haplogroup O2b-SRY465 (and its sublineage) is characteristic of male Koreans, whereas the haplogroup distribution elsewhere in East Asian populations is patchy. The ages of the haplogroup O2b-SRY465 lineages (~9,900 years) and the pattern of variation within the lineages suggested an ancient origin in a nearby part of northeastern Asia, followed by an expansion in the vicinity of the Korean Peninsula. In addition, the coalescence time (~4,400 years) for the age of haplogroup O2b1-47z, and its Y-STR diversity, suggest that this lineage probably originated in Korea. Further studies with sufficiently large sample sizes to cover the vast East Asian region and using genomewide genotyping should provide further insights.</p> <p>Conclusions</p> <p>These findings are consistent with linguistic, archaeological and historical evidence, which suggest that the direct ancestors of Koreans were proto-Koreans who inhabited the northeastern region of China and the Korean Peninsula during the Neolithic (8,000-1,000 BC) and Bronze (1,500-400 BC) Ages.</p
Extracorporeal cardiopulmonary resuscitation for adult out-of-hospital cardiac arrest patients: time-dependent propensity score-sequential matching analysis from a nationwide population-based registry
Background
There is inconclusive evidence regarding the effectiveness of extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA) patients. We aimed to evaluate the association between ECPR and neurologic recovery in OHCA patients using time-dependent propensity score matching analysis.
Methods
Using a nationwide OHCA registry, adult medical OHCA patients who underwent CPR at the emergency department between 2013 and 2020 were included. The primary outcome was a good neurological recovery at discharge. Time-dependent propensity score matching was used to match patients who received ECPR to those at risk for ECPR within the same time interval. Risk ratios (RRs) and 95% confidence intervals (CIs) were estimated, and stratified analysis by the timing of ECPR was also performed.
Results
Among 118,391 eligible patients, 484 received ECPR. After 1:4 time-dependent propensity score matching, 458 patients in the ECPR group and 1832 patients in the no ECPR group were included in the matched cohort. In the matched cohort, ECPR was not associated with good neurological recovery (10.3% in ECPR and 6.9% in no ECPR; RR [95% CI] 1.28 [0.85–1.93]). In the stratified analyses according to the timing of matching, ECPR with a pump-on within 45min after emergency department arrival was associated with favourable neurological outcomes (RR [95% CI] 2.51 [1.33–4.75] in 1–30min, 1.81 [1.11–2.93] in 31–45min, 1.07 (0.56–2.04) in 46–60min, and 0.45 (0.11–1.91) in over 60min).
Conclusions
ECPR itself was not associated with good neurological recovery, but early ECPR was positively associated with good neurological recovery. Research on how to perform ECPR at an early stage and clinical trials to evaluate the effect of ECPR is warranted
In Vitro inhibitory activity of Alpinia katsumadai extracts against influenza virus infection and hemagglutination
<p>Abstract</p> <p>Background</p> <p><it>Alpinia katsumadai </it>(AK) extracts and fractions were tested for <it>in vitro </it>antiviral activities against influenza virus type A, specially human A/PR/8/34 (H1N1) and avian A/Chicken/Korea/MS96/96 (H9N2), by means of time-of-addition experiments; pre-treatment, simultaneous treatment, and post treatment.</p> <p>Results</p> <p>In pre-treatment assay, the AK extracts and AK fractions did not show significant antiviral activity. During the simultaneous treatment assay, one AK extract and five AK fractions designated as AK-1 to AK-3, AK-5, AK-10, and AK-11 showed complete inhibition of virus infectivity against A/PR/8/34 (H1N1) and A/Chicken/Korea/MS96/96 (H9N2). The 50% effective inhibitory concentrations (EC<sub>50</sub>) of these one AK extracts and five AK fractions with exception of the AK-9 were from 0.8 ± 1.4 to 16.4 ± 4.5 <it>μ</it>g/mL against A/PR/8/34 (H1N1). The two AK extracts and three AK fractions had EC<sub>50 </sub>values ranging from <0.39 ± 0.4 to 2.3 ± 3.6 <it>μ</it>g/mL against A/Chicken/Korea/MS96/96 (H9N2). By the hemagglutination inhibition (HI) assay, the two AK extracts and five AK fractions completely inhibited viral adsorption onto chicken RBCs at less than 100 <it>μ</it>g/mL against both A/PR/8/34 (H1N1) and A/Chicken/Korea/MS96/96 (H9N2). Interestingly, only AK-3 was found with inhibition for both viral attachment and viral replication after showing extended antiviral activity during the post treatment assay and quantitative real-time PCR.</p> <p>Conclusions</p> <p>These results suggest that AK extracts and fractions had strong anti-influenza virus activity that can inhibit viral attachment and/or viral replication, and may be used as viral prophylaxis.</p
Heart Transplantation in Pediatric Patients: Twelve-Year Experience of the Asan Medical Center
Heart transplantation is a standard treatment for end-stage heart disease. Pediatric heart transplantation, however, is not frequently performed due to the shortage of pediatric heart donors. This is the first report of pediatric heart transplantation in Korea. Our retrospective study included 37 patients younger than 18 yr of age who underwent heart transplantation at Asan Medical Center between August 1997 and April 2009. Preoperative diagnosis was either cardiomyopathy (n = 29, 78.3%) or congenital heart disease (n = 8, 22.7%). Mean follow up period was 56.9 ± 44.6 months. There were no early death, but 7 late deaths (7/37, 18.9%) due to rejection after 11, 15, 41 months (n = 3), infection after 5, 8, 10 months (n = 3), suspicious ventricular arrhythmia after 50 months (n = 1). There was no significant risk factor for survival. There were 25 rejections (25/37, 67.6%); less than grade II occurred in 17 patients (17/25, 68%) and more than grade II occurred in 8 patients (8/25, 32%). Actuarial 1, 5, and 10 yr survival was 88.6%, 76.8%, and 76.8%. Our midterm survival of pediatric heart transplantation showed excellent results. We hope this result could be an encouraging message to do more pediatric heart transplantation in Korean society
Protection of chickens from Newcastle disease with a recombinant baculovirus subunit vaccine expressing the fusion and hemagglutininneuraminidase proteins
Recombinant baculoviruses containing the fusion (F) and
hemagglutinin-neuraminidase (HN) glycoprotein gene of
the viscerotropic velogenic (vv) Newcastle disease virus
(NDV) isolate, Kr-005/00, and a lentogenic La Sota strain
of the NDV were constructed in an attempt to develop an
effective subunit vaccine to the recent epizootic vvNDV.
The level of protection was determined by evaluating the
clinical signs, mortality, and virus shedding from the
oropharynx and cloaca of chickens after a challenge with
vvNDV Kr-005/00. The recombinant ND F (rND F) and
recombinant HN (rND HN) glycoproteins derived from
the velogenic strain provided good protection against the
clinical signs and mortality, showing a 0.00 PI value and
100% protection after a booster immunization. On the
other hand, the combined rND F + HN glycoprotein
derived from the velogenic strain induced complete
protection (0.00 PI value and 100% protection) and
significantly reduced the amount of virus shedding even
after a single immunization. The rND F and rND HN
glycoproteins derived from the velogenic strain had a
slightly, but not significantly, greater protective effect
than the lentogenic strain. These results suggest that the
combined rND F + HN glycoprotein derived from vvNDV
can be an ideal subunit marker vaccine candidate in
chickens in a future ND eradication program
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