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Background and Objective Although sirtuin 1 ( SIRT1) over-expression and resveratrol exert anti-inflammatory and proinflammatory effects, their effects and the mechanism of action on human gingival fibroblast ( HGF)-mediated inflammation are unknown. The aim of this study was to demonstrate the effects of activating SIRT1 using resveratrol and recombinant adenovirus encoding SIRT1 (Ad- SIRT1) on the expression of proinflammatory cytokines and to elucidate its mechanism of action of lipopolysaccharide ( LPS) and nicotine stimulated- HGF. Material and Methods Cytotoxicity and the production of reactive oxygen species (ROS) were measured using the 3-(4,5-dimethylthiazolyl-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry, respectively. The amount of prostaglandin E2 (PGE2) released into the culture medium was measured by radioimmunoassay. mRNA and protein levels were analyzed using RT-PCR and western blotting, respectively. Results Nicotine and LPS up-regulated the expression of SIRT1 mRNA and SIRT1 protein in a time- and concentration-dependent manner. Resveratrol and Ad-SIRT1 decreased LPS and nicotine-induced cytotoxicity, ROS and PGE2 production, and expression of cyclooxygenase-2 in HGFs. Resveratrol and Ad-SIRT1 inhibited nicotine and LPS-mediated protein kinase C (PKC), phosphatidylinositol 3-kinase (PI3K), p38, ERK, JNK, MAPK and nuclear factor-kappa B (NF-κB) activation. Conclusion This study is the first to show that the anti-inflammatory and cytoprotective effects of SIRT1 activation in HGFs occur through the PKC, PI3K, MAPK and NF-κB pathways. [ABSTRACT FROM AUTHOR]

In Korea, it takes time to transport the ovaries of mares to the laboratory because horses are slaughtered only on Jeju island. Also, initiation of in vitromaturation (IVM) may be a little more delayed because of the oocyte collection by scraping of the follicular wall. It was reported that holding procedure of equine oocytes before IVM did not affect the developmental competence after intracytoplasmic sperm injection (Choi et al.2006 Theriogenology 66, 955–963). The aims of present study were 1) to investigate the meiotic competence of equine oocytes held before IVM according to the type of oocytes, and 2) to examine the in vitrodevelopment after somatic cell nuclear transfer (SCNT). Cumulus–oocyte complexes (COCs) were recovered by scraping and washing of the follicular wall with Dulbecco’s modified Eagle medium (D-MEM) supplemented with 0.05% PVA, and classified as compact (Cp) or expended (Ex) depending on the expansion of cumulus or granulosa cells. 2 types of IVM procedures were compared: 1) COCs were matured immediately in IVM medium (TCM-199 supplemented with 5mUmL-1FSH, 50ngmL-1EGF, and 10% FBS) at 38.5°C under 5% CO2in air for 24 to 27h, and then held in holding medium (40% TCM-199 with Earle’s salts, 40% TCM-199 with Hanks’ salts, and 20% FBS) at room temperature for 6 to 7h (control); or 2) COCs were initially held in holding medium for 6 to 7h, and then matured in IVM medium for 24 to 27h (holding). For SCNT, matured oocytes (pooled) were enucleated and electrically fused with equine skin fibroblasts (2.25kVcm-1, 20μs, 2 pulses). Fused couplets were activated with 5μM ionomycin for 4min followed by 5h culture in 2mM 6-DMAP, and cultured in D-MEM supplemented with 10% FBS and 50ngmL-1EGF at 38.5°C under 5% CO2, 5% O2, and 90% N2for 7 to 9 days. Cleavage and blastocyst formation were evaluated on Days 2 and 8, respectively. All analyses were performed using SAS (version 9.1; SAS Institute Inc., Cary, NC, USA). 4 replicates were conducted from May to June 2010. In Ex oocytes, the maturation rate of the holding group (71.4%; 10/16) was not different from that of the control (65.6%; 44/73), and the rate of degenerated oocytes (4.8%; 1/16) in the holding group was not different from that in the control (5.6%; 5/73). However, in Cp oocytes, the degeneration rate of the holding group (65.0%; 31/49) was higher (P<0.001) than that of the control (28.4%; 23/83), and the maturation rate of the holding group (20.6%; 12/49) was slightly lower (P=0.07) than that of the control (46.0%; 38/83). After SCNT, the cleavage rate of the holding group (66.7%; 8/9) was not different from that of the control (60.8%; 14/25), and the rates of blastocyst formation of the control and the holding group were 8.1% (2/25) and 16.7% (2/9), respectively. Although the holding procedure may influence to the degeneration of Cp oocytes, it is considered that the developmental competence of equine oocytes held before IVM is not affected after SCNT. [ABSTRACT FROM AUTHOR]

A single-particle analytical technique, named low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA), employing an ultrathin window X-ray detector and enabling the quantitative determination of even low-Z elements such as C, N, and O, is applied to characterize "Asian Dust" samples, collected in ChunCheon, Korea, during four Asian Dust storm events on March 7, 2000, April 7, 2000, March 22, 2001, and May 17, 2001. In this study, it is demonstrated that single-particle analysis using the low-Z particle EPMA provides detailed information on various types of chemical species in the samples. The most abundantly encountered particles, both in coarse and fine fractions, are aluminosilicates. The relative abundances of those particles on the basis of their size are different between the four Asian Dust samples. The sample collected on March 7, 2000 did not experience any chemical modification during its transport because the sample does not contain particles of chemical species that result from atmospheric reactions. The sample collected on April 7, 2000 contains both genuine and reacted sea-salt particles. The genuine sea-salts are in the form of a mixture of NaCl and MgCl2 entrained during their passage over the Yellow Sea. The reacted sea-salts particles are encountered very much in fine fraction. The sample collected on March 22, 2001 shows somewhat significant chemical modification both for CaCO3 and sea-salts particles. For this sample, a significant number of reacted CaCO3 and sea-salt particles, such as those containing nitrate and/or sulfate, are encountered, implying that CaCO3 and sea-salts particles have reacted with sulfur or nitrogen oxide species during their long-range transport. The sample collected on May 17, 2001 experienced the most extensive chemical modification during its transport. In addition to the observation of the extensively reacted CaCO3 and sea-salt particles, reacted K2CO3 particles are also extensively encountered in this sample, which implies that K2CO3 species should be regarded as an additional important chemical species in the study of the chemical modification of Asian Dust particles during long-range transport.

The Korean peninsula has a long history of dust clouds blown by winds from the arid deserts of Mongolia and China in springtime; these are called Asian dust events. Public concern about the possible adverse effects of this dust has increased, because the dust arrives in Korea after having passed over heavily industrialized eastern China. The present study explored the effect of Asian dust events on daily mortality in Seoul, South Korea, during the period 1995-1998. We evaluated the association between daily death counts and the dust events using Poisson regression analysis, adjusted for time trends, weather variables, and the day of the week. Between 1995 and 1998, we identified 28 Asian dust days in Seoul. The estimated percentage increase in the rate of deaths from 3-day moving averages of exposure was 1.7% (95/ confidence interval: -1.6 to 5.3) for all causes, 2.2% (95% confidence interval: -3.5 to 8.3) for deaths of persons aged 65 years and older, and 4.1% (95% confidence interval: -3.8 to 12.6) for cardiovascular and respiratory causes. Our results provide weak evidence that the Asian dust events are associated with risk of death from all causes. However, the association between the dust events and deaths from cardiovascular and respiratory causes was stronger and it suggests that persons with advanced cardiovascular and respiratory disease may be susceptible to the Asian dust events.

Objective: Mutations in the GJB2 gene are a major cause of autosomal recessive and sporadic types of congenital deafness. The 35delG mutation is the most frequent type of mutation in white populations. However, several other forms were reported, such as 167delT among Ashkenazi Jews and R143W in Africans. The present study investigated the mutations of connexin26 (Cx26) found in patients with nonsyndromic hearing loss (NSHL) and newborns in the Korean population., Study Design: The sequencing data for 147 unrelated patients with congenital NSHL and 100 audiologically screened newborns were included in this prospective study., Methods: Genomic DNA samples from all patients and newborns were sequenced in both directions for detection of Cx26 mutations., Results: Thirteen different types of mutations were found in the patients and newborns. V27I and E114G are the popular types of polymorphic mutations in both groups. 235delC-deletion and frameshift--was detected in patients (15 in 294 alleles) and newborns (1 in 200 alleles). 35delG was rarely found in both group. In addition to above mutations, several types of mutations--S85P, K41R, S72C, V84A, 176-191del, and 299-300del-were identified. The family study of the 235delC showed a typical autosomal recessive trait of NSHL in their audiological evaluation of hearing threshold., Conclusion: The frequency of 235delC allele showed much higher in the patients (5%) than in newborns (0.5%). We rarely found 35delC mutant in both groups. These results suggest that the different types of Cx26 mutations affect autosomal recessive NSHL according to ethnic background.