BackgroundSarcopenia is the loss of muscle mass leading to decreased muscle strength, physical disability, and increased mortality. The genesis of both sarcopenia and osteoporosis is multifactorial, and several factors that play a role in osteoporosis are thought to contribute to sarcopenia. This study evaluated the association between sarcopenia and bone density and health-related quality of life in Korean men.MethodsWe used the data of 1,397 men over 50 years of age from the 2009 Korean National Health and Nutrition Examination Survey. Sarcopenia was defined as the appendicular skeletal muscle mass divided by height2 (kg/m2) < 2 standard deviations below the sex-specific mean for young adults. Health-related quality of life was measured by the EuroQol-5 dimension (EQ-5D) instrument. Logistic regression analysis was performed to evaluate the relationship between sarcopenia, bone density, and health-related quality of life.ResultsThe T-score of the lumbar spine, total femur, and femur neck in bone mineral density in subjects with sarcopenia were lower than those in subjects without sarcopenia. The score of the EQ-5D index was significantly lower and the rate of having problems with individual components of health-related quality of life was higher in the sarcopenic group. After adjustment for age and body mass index, the odds ratios (ORs) (95% confidence interval [CI]) for sarcopenia were 2.06 (1.07-3.96) in osteopenic subjects and 3.49 (1.52-8.02) in osteoporotic subjects, respectively. After adjustment, the total score of the EQ-5D index was significantly lower in the sarcopenic subjects. The ORs (95% CI) for having problems of mobility and usual activity of the EQ-5D descriptive system were 1.70 (1.02-2.84) and 1.90 (1.09-3.31), respectively.ConclusionSarcopenia was associated with decreased bone mineral density in Korean men. In addition, sarcopenia was related to poor quality of life, especially with regard to mobility and usual activity. Greater attention to and evaluation for sarcopenia are needed in subjects showing low bone mineral density to prevent and manage poor quality of life.

The influence of annealing on the constitutive stress-strain response of nanocrystalline (nc) CoCrFeMnNi high-entropy alloy (HEA) was investigated through a series of nanoindentation experiments using five different three-sided pyramidal indenters. The nc HEA, produced by high-pressure torsion (HPT), was subjected to annealing at 450 o C for 1 and 10 h. Microstructural analysis using transmission electron microscopy (TEM) showed that three different nano-scale precipitates (NiMn-, FeCo-, and Co-rich phases) form in the primary single-phase matrix of nc HEA after annealing. The strain-dependent plastic flow response of nc HEA pre-and post-annealing was estimated using the indentation strain and constraint factor, revealing a significant strain softening in nc HEA, which becomes pronounced after annealing. TEM analysis of the deformed material underneath the indenter suggests that the plastic deformation aids in the dissolution of the annealing-induced intermetallic precipitates, which could be the mechanism for the pronounced softening. The dissolution mechanismwas 2 rationalized by the destabilization of precipitates during plastic deformation due to the increase in interface energy.

The natural history of hepatitis B virus (HBV) infection is probably related to host immune factors. Interferon-c (IFN-c) plays significant roles in immune defense. This study was undertaken to investigate the association between HBV infection and single nucleotide polymorphisms (SNPs) of IFN-c, IFN-c receptor (IFNGR)-1 and 2, and interferon regulatory factor (IRF)-1 genes. Between March 2002 and December 2002, 614 Korean patients were enrolled in two different groups: an HBV clearance group (n = 201), who were hepatitis B surface antigen (HBsAg) negative with antibodies to HBsAg and hepatitis B core antigen, and an HBV persistence group (n = 413), who were repeatedly HBsAg positive. We assessed polymorphisms in the IFN-c gene at position +874, in the IFNGR-1 gene at positions )56 and +95, in the IFNGR-2 gene at the second position of codon 64 (Gln64Arg), and in the IRF-1 gene promoter ()410, )388), and the genotype distributions of the HBV clearance and persistence groups were compared. On the basis of unconditional logistic regression analysis with adjustment for age and sex, no statistically significant association with susceptibility to persistent HBV infection was observed with the IFN-c,

Background/Aim The natural course of hepatitis B virus (HBV) infection is likely related to host immune factors. Interleukin-18 (IL-18) plays a significant role in immune defense. This study was undertaken to determine the association between the presence of hepatocellular carcinoma (HCC) and single-nucleotide polymorphisms (SNPs) in the IL-18 gene in HBV-infected patients.

Recovery from hepatitis B virus (HBV) infection depends on the cellular immune responses. Chemokines and their receptors play significant roles in immune defense. This study was undertaken to investigate the association between HBV infection and single nucleotide polymorphisms (SNPs) of genes for the chemokines and their receptors. Between March 2002 and February 2004, a total of 957 single ethnic Korean patients were enrolled into two different groups; "HBV clearance group" (n=350), who have recovered from HBV infection, and "HBV persistence group" (n=607), who were repeatedly HBsAg-positive. The HBV persistence group was subdivided into "inactive carrier" and "HBV progression group (chronic hepatitis and cirrhosis)". We assessed polymorphisms in regulated and normal T-cell expressed and secreted (RANTES) at position -403, monocyte chemoattractant protein-1 (MCP-1) at position -2518, CCR2 V64I, CCR5 -2459, CXCR1 S276T and CXCR4 I138I using single primer extension assay. Genotype distributions of the "HBV clearance versus persistence group" and "inactive carrier versus HBV progression group" were compared. On the basis of unconditional logistic regression analysis with adjustment for age and sex, no statistically significant association with susceptibility to persistent HBV infection was observed with RANTES -403, MCP-1 -2518, CCR2 V64I, CCR5 -2459, CXCR1 S276T, and CXCR4 I138I polymorphisms. In addition, no association of analyzed SNPs with HBV disease progression was found.