Stereochemical aspects of diels-alder reaction of substituted penta-2,4-dienols and maleic anhydride derivatives

Reaction of diene alcohol5 and maleic anhydride in benzene at either room temperature or reflux proceeds probably through a intermolecular Diels-Alder cycloaddition followed by lactone formation to give adduct6.     

Analysis of the Effects of Nutrient Intake and Dietary Habits on Depression in Korean Adults

While several studies have explored nutrient intake and dietary habits associated with depression, few studies have reflected recent trends and demographic factors. Therefore, we examined how nutrient intake and eating habits are associated with depression, according to gender and age. We performed simple and multiple regressions using nationally representative samples of 10,106 subjects from the Korea National Health and Nutrition Examination Survey. The results indicated that cholesterol, dietary fiber, sodium, frequency of breakfast, lunch, dinner, and eating out were significantly associated with depression (p-value < 0.05). Moreover, depression was associated with nutrient intake and dietary habits by gender and age group: sugar, breakfast, lunch, and eating out frequency in the young women’s group; sodium and lunch frequency among middle-age men; dietary fibers, breakfast, and eating out frequency among middle-age women; energy, moisture, carbohydrate, lunch, and dinner frequency in late middle-age men; breakfast and lunch frequency among late middle-age women; vitamin A, carotene, lunch, and eating out frequency among older age men; and fat, saturated fatty acids, omega-3 fatty acid, omega-6 fatty acid, and eating out frequency among the older age women’s group (p-value < 0.05). This study can be used to establish dietary strategies for depression prevention, considering gender and age.     

Genomic Surveillance of SARS-CoV-2: Distribution of Clades in the Republic of Korea in 2020

Since a novel beta-coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first reported in December 2019, there has been a rapid global spread of the virus. Genomic surveillance was conducted on samples isolated from infected individuals to monitor the spread of genetic variants of SARS-CoV-2 in Korea. The Korea Disease Control and Prevention Agency performed whole genome sequencing of SARS-CoV-2 in Korea for 1 year (January 2020 to January 2021). A total of 2,488 SARS-CoV-2 cases were sequenced (including 648 cases from abroad). Initially, the prevalent clades of SARS-CoV-2 were the S and V clades, however, by March 2020, GH clade was the most dominant. Only international travelers were identified as having G or GR clades, and since the first variant 501Y.V1 was identified (from a traveler from the United Kingdom on December 22^nd, 2020), a total of 27 variants of 501Y.V1, 501Y.V2, and 484K.V2 have been classified (as of January 25^th, 2021). The results in this study indicated that quarantining of travelers entering Korea successfully prevented dissemination of the SARS-CoV-2 variants in Korea.     

Former Foster System Youth: Perspectives on Transitional Supports and Programs

The Journal of Behavioral Health Services & Research - Youth aging out of the foster care system have well-documented challenges when transitioning to adulthood. Multiple transition services...     

Culture-Expanded Autologous Adipose-Derived Mesenchymal Stem Cell Treatment for Osteonecrosis of the Femoral Head

BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.     

Systematic assessment of South Korea’s capabilities to control COVID-19

South Korea’s COVID-19 control strategy has been widely emulated. Korea’s ability to rapidly achieve disease control in early 2020 without a “Great Lockdown” despite its proximity to China and high population density make its achievement particularly intriguing. This paper helps explain Korea’s pre-existing capabilities which enabled the rapid and effective implementation of its COVID-19 control strategies. A systematic assessment across multiple domains demonstrates that South Korea’s advantages in controlling its epidemic are owed tremendously to legal and organizational reforms enacted after the MERS outbreak in 2015. Successful implementation of the Korean strategy required more than just a set of actions, measures and policies. It relied on a pre-existing legal framework, financing arrangements, governance and a workforce experienced in outbreak management.     

In vitro cellular immune responses to recombinant antigens of Mycobacterium avium subsp. paratuberculosis

Five recombinant antigens (Ags; 85A, 85B, 85C, superoxide dismutase [SOD], and 35-kDa protein) were purified from Mycobacterium avium subsp. paratuberculosis and evaluated for their ability to stimulate peripheral blood mononuclear cells (PMBCs) from fecal-culture-positive cows (low and medium shedders) and culture-negative healthy cows. Recombinant Ags 85A, 85B, and 85C induced significant lymphocyte proliferation as well as the production of gamma interferon (IFN-gamma), interleukin-2 (IL-2), IL-12, and tumor necrosis factor alpha (TNF-alpha), but not IL-4, from low and medium shedders. The 85 antigen complex did not stimulate PMBC proliferation from culture-negative healthy cows. The 35-kDa protein also induced significant lymphocyte proliferation as well as the production of IFN-gamma and IL-4 from low and medium shedders. CD4(+) T cells and CD25(+) (IL-2R) T cells were stimulated the most by 85A and 85B, while the 35-kDa protein primarily stimulated CD21(+) B cells involved in humoral immune responses. Interestingly, SOD was less immunostimulatory than other antigens but strongly induced gammadelta(+) T cells, which are thought to be important in the early stages of infection, such as pathogen entry. These data provide important insight into how improved vaccines against mycobacterial infections might be constructed.     

Pretreatment of low dose radiation reduces radiation-induced apoptosis in mouse lymphoma (EL4) cells

Induction of an adaptive response to ionizing radiation in mouse lymphoma (EL4) cells was studied by using cell survival fraction and apoptotic nucleosomal DNA fragmentation as biological end points. Cells in early log phase were pre-exposed to low dose of γ-rays (0.01 Gy) 4 or 20 hrs prior to high dose γ-ray (4, 8 and 12 Gy for cell survival fraction analysis; 8 Gy for DNA fragmentation analysis) irradiation. Then cell survival fractions and the extent of DNA fragmentation were measured. Significant adaptive response, increase in cell survival fraction and decrease in the extent of DNA fragmentation were induced when low and high dose γ-ray irradiation time interval was 4 hr. Addition of protein or RNA synthesis inhibitor, cycloheximide or 5,6-dichloro-1-β-d-ribofuranosylbenzimidazole (DRFB), respectively during adaptation period, the period from low dose γ-ray irradiation to high dose γ-ray irradiation, was able to inhibit the induction of adaptive response, which is the reduction of the extent DNA fragmentation in irradiated EL4 cells. These data suggest that the induction of adaptive response to ionizing radiation in EL4 cells required both protein and RNA synthesis.     

Flavonoids fromCirsium rhinoceros

Six flavonoids were isolated from the aerial parts ofCirsium rhinoceros. The flavonoids were identified as apigenin, luteolin, pectolinarigenin-7-O-β-D-glucopyranoside, linarin, pectolinarin and hispidulin-7-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside on the basis of chemical and spectral evidence.     

Limitations in the use of tubulin polymerization assays as a screen for the identification of new antimitotic agents: The potent marine natural product curacin A as an example

Curacin A is a newly isolated lipid natural product that binds in the colchicine site of tubulin and inhibits mitosis. We have examined its effects on tubulin polymerization, studied by turbidimetry, under three reaction conditions. In 1.0 M glutamate + 1.0 mM MgCl₂, with a 37°C reaction temperature, we could find no concentration of curacin A that completely inhibited polymerization. A maximal inhibitory effect on turbidity development (about 50%) was observed with 5 m?M drug. Higher drug concentrations induced an abnormal polymerization reaction, which at 40 m?M differed little from the control reaction except for slightly delayed depolymerization in response to reducing the temperature to 0°C. In 0.8 M glutamate (no MgCl₂), with a 30°C reaction temperature, complete inhibition did occur at 3–5 m?M drug, but higher drug concentrations again induced an abnormal polymerization reaction. With 40 m?M curacin A this reaction was also similar to the control reaction, except that cold-induced depolymerization was slightly enhanced relative to the control. When polymerization was induced by microtubule-associated proteins, maximal inhibition of turbidity development (about 70%) occurred with 2 m?M drug, with higher curacin A concentrations inducing abnormal polymerization reactions that reached about 60% of the control turbidity readings. Under all three reaction conditions the polymer induced by high concentrations of curacin A consisted of large aggregates of tightly coiled spiral fibers that had a 2–3 filament substructure. The implications of these findings with curacin A are discussed in terms of the use of tubulin polymerization assays as a screen for identifying new antimitotic drugs. © 1995 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.