Association between Multiple Trace Elements, Executive Function, and Cognitive Impairment with No Dementia in Older Adults

Many studies suggest a significant association between individual essential trace elements (ETEs) and cognitive impairment in older adults, but evidence of the synchronized effect of multiple ETEs on cognitive function is lacking. We investigated the association between multiple ETEs, cognitive impairment with no dementia (CIND), and executive function in older Korean adults, using the Bayesian kernel machine regression (BKMR) model. Three hundred and thirty-six older adults were included as the study population and classified as the CIND and control groups. Blood manganese (Mn), copper (Cu), zinc (Zn), selenium (Se), and molybdenum (Mo) were measured as relevant ETEs. The frontal/executive tests included digit symbol coding (DSC), the Korean color word Stroop test (K-CWST), a controlled oral word association test (COWAT), and a trial-making test (TMT). Overall, the BKMR showed a negative association between multiple ETEs and the odds of CIND. Mn was designated as the most dominant element associated with the CIND (PIP = 0.6184), with a U-shaped relationship. Cu and Se levels were positively associated with the K-CWST percentiles (β = 31.78; 95% CI: 13.51, 50.06) and DSC percentiles (β = 25.10; 95% CI: 7.66, 42.53), respectively. Our results suggest that exposure to multiple ETEs may be linked to a protective mechanism against cognitive impairment in older adults.

Increased breast cancer incidence among nurses in a tertiary university hospital in South Korea

Background

A series of breast cancer cases were recently reported in a tertiary university hospital in South Korea. Nurses are generally exposed to risk factors for breast cancer such as night shift work, antineoplastic agents, and job strain. However, the epidemiological evidence of excess incidence among nurses remains lacking. This study aims to investigate the excess incidence of breast cancer among nurses in a tertiary university hospital and provide epidemiological evidence of occupational risk factors.

Methods

A retrospective cohort was developed using personnel records of female workers in the nursing department who worked from January 2011 to June 2021 in a tertiary university hospital in South Korea. Sick leave records were used to identify cases of breast cancer. The standardized incidence ratio of breast cancer among nurses was compared to the general population.

Results

A total of 5,509 nurses were followed up for 30,404 person-years, and 26 breast cancer cases were identified. This study revealed a significantly increased breast cancer incidence among all included nurses, with a standardized incidence ratio of 1.65 (95% confidence interval [CI]: 1.08-2.41), compared to the general population. Workers, who handle antineoplastic agents in their representative department and current and/or former department, had significantly elevated breast cancer standardized incidence ratios of 2.73 (95% CI: 1.008-5.94) and 3.39 (95% CI: 1.46-6.68), respectively.

Conclusions

This study provides significant evidence of increased breast cancer risk among nursing staff in a hospital setting, particularly those who handle antineoplastic drugs. Measures that reduce exposure to risk factors should be implemented, especially anticancer drugs, to protect healthcare professionals. Further research at a national level that focuses on healthcare workers is necessary to validate breast cancer incidence and its contributing factors.

BLZ8 activates a plastidial peroxiredoxin and a ferredoxin to protect Chlamydomonas reinhardtii against oxidative stress

Reactive oxygen species (ROS) cause damage to various cellular processes in almost all organisms, in particular photosynthetic organisms that depend on the electron transfer chain for CO2 fixation. However, the detoxifying process to mitigate ROS damage has not been studied intensively in microalgae. Here, we characterized the ROS detoxifying role of a bZIP transcription factor, BLZ8, in Chlamydomonas reinhardtii. To identify downstream targets of BLZ8, we carried out comparative genome-wide transcriptomic profiling of BLZ8 OX and its parental CC-4533 under oxidative stress conditions. Luciferase reporter activity assays and RT-qPCR were performed to test whether BLZ8 regulates downstream genes. We performed an in silico functional gene network analysis and an in vivo immunoprecipitation assay to identify the interaction between downstream targets of BLZ8. Comparative transcriptomic analysis and RT-qPCR revealed that overexpression of BLZ8 increased the expression levels of plastid peroxiredoxin1 (PRX1) and ferredoxin-5 (FDX5) under oxidative stress conditions. BLZ8 alone could activate the transcriptional activity of FDX5 and required bZIP2 to activate transcriptional activity of PRX1. Functional gene network analysis using FDX5 and PRX1 orthologs in A. thaliana suggested that these two genes were functionally associated. Indeed, our immunoprecipitation assay revealed the physical interaction between PRX1 and FDX5. Furthermore, the complemented strain, fdx5 (FDX5), recovered growth retardation of the fdx5 mutant under oxidative stress conditions, indicating that FDX5 contributes to oxidative stress tolerance. These results suggest that BLZ8 activates PRX1 and FDX5 expression, resulting in the detoxification of ROS to confer oxidative stress tolerance in microalgae.

Telecommuting-related health outcomes during the COVID-19 pandemic in South Korea: a national population-based cross-sectional study

BACKGROUND

Telecommuting has expanded greatly during the COVID-19 pandemic. Since the advent of remote working from home, there has been an ongoing controversy about the positive or negative health-related impact of telecommuting. This study aimed to investigate change in the occupational health risk in South Korean workers involved in telecommuting during the pandemic period compared to daily commuters.

METHODS

A population-based cross-sectional study of South Korean workers using the secondary data from the 6th Korean Working Conditions Survey (2020-2021) was designed. A total of 12,354 white-collar wage employees were selected as the study sample. Telecommuting, depression, anxiety, insomnia, fatigue, musculoskeletal pain, headache-eye strain, absenteeism, and presenteeism were measured by self-reported data. Multiple logistic regression models, including gender stratification analysis, were used to estimate the adjusted odds ratio (AOR) with a 95% confidence interval (CI) for the health outcomes of telecommuters.

RESULTS

Among the study population, 338 males and 318 females were reported to be telecommuters. The entirely adjusted regression model showed a positive association between telecommuting and anxiety (AOR = 2.82; 95% CI, 1.93-4.10), insomnia (AOR = 1.93; 95% CI, 1.27-2.92), fatigue (AOR = 1.76; 95% CI, 1.30-2.37), musculoskeletal pain (AOR = 1,76; 95% CI, 1.33-2.32), headache-eye strain (AOR = 1.94; 95% CI, 1.48-2.54), presenteeism (AOR = 1.66; 95% CI, 1.20-2.28) respectively. Gender difference was identified in that only female telecommuters had a higher risk of depression (AOR = 1.62; 95% CI, 1.04-2.53) and insomnia (AOR = 2.07; 95% CI, 1.26-3.41) than daily commuters in the adjusted model.

CONCLUSION

Telecommuting was significantly associated with an increased risk of various health problems among South Korean workers and females were identified as a more vulnerable group. Although further research is required to ascertain the causal relationship, public health intervention should be considered to prevent the negative effects of telecommuting.

Acetylcholine precursor, citicoline (cytidine 5'-diphosphocholine), reduces hypoglycaemia-induced neuronal death in rats

Citicoline (cytidine 5'-diphosphocholine) is an important precursor for the synthesis of neuronal plasma membrane phospholipids, mainly phosphatidylcholine. The administration of citicoline serves as a choline donor for the synthesis of acetylcholine. Citicoline has been shown to reduce the neuronal injury in animal models with cerebral ischaemia and in clinical trials of stroke patients. Citicoline is currently being investigated in a multicentre clinical trial. However, citicoline has not yet been examined the context of hypoglycaemia-induced neuronal death. To clarify the therapeutic impact of citicoline in hypoglycaemia-induced neuronal death, we used a rat model with insulin-induced hypoglycaemia. Acute hypoglycaemia was induced by i.p. injection of regular insulin (10 U kg^-1 ) after overnight fasting, after which iso-electricity was maintained for 30 minutes. Citicoline injections (500 mg/kg, i.p.) were started immediately after glucose reperfusion. We found that post-treatment of citicoline resulted in significantly reduced neuronal death, oxidative injury and microglial activation in the hippocampus compared to vehicle-treated control groups at 7 days after induced hypoglycaemia. Citicoline administration after hypoglycaemia decreased immunoglobulin leakage via blood-brain barrier disruption in the hippocampus compared to the vehicle group. Citicoline increased choline acetyltransferase expression for phosphatidylcholine synthesis after hypoglycaemia. Altogether, the present findings suggest that neuronal membrane stabilisation by citicoline administration can save neurones from the degeneration process after hypoglycaemia, as seen in several studies of ischaemia. Therefore, the results suggest that citicoline may have therapeutic potential to reduce hypoglycaemia-induced neuronal death.

Dietary total, animal, vegetable calcium and type 2 diabetes incidence among Korean adults: The Korean Multi-Rural Communities Cohort (MRCohort)

BACKGROUND AND AIMS

Although a possible mechanism for developing type 2 diabetes in relation to calcium intake has been suggested, there is currently little epidemiological evidence on the association between dietary calcium and type 2 diabetes (T2D). This study aimed to evaluate the prospective association between dietary calcium and T2D incidence among adults 40 years of age or over, from the Multi-rural Communities Cohort (MRCohort), South Korea.

METHODS AND RESULTS

In total, 8313 participants (3033 men and 5280 women) who did not have diabetes at baseline were recruited between 2005 and 2013. The incidence rate ratio (IRR) was estimated using a modified Poisson regression model with a robust error estimator. During follow-up (31,570 person-years), 322 T2D cases were newly diagnosed. Dietary calcium (total and vegetable calcium) were inversely associated with the risk of T2D incidence among women (IRR = 0.61, 95% CI = 0.43-0.86, P for trend = 0.007 in third tertile of baseline total calcium intake comparing to the first tertile; IRR = 0.57, 95% CI = 0.39-0.84, P for trend = 0.006 for baseline vegetable calcium intake), not for men. The tendency of those inverse associations remained in both the normal fasting blood glucose group and the impaired fasting blood glucose group and were independent of obesity, smoking, and magnesium intake.

CONCLUSIONS

Total and vegetable calcium may be inversely associated with T2D incidence among women, regardless of impaired fasting blood glucose group or normal group. The associations may be potentially dose-responsive. Moderate dietary calcium may be related to lower risk of T2D incidence comparing to low intake group among women.

High reproduction number of Middle East respiratory syndrome coronavirus in nosocomial outbreaks: mathematical modelling in Saudi Arabia and South Korea

Background

Effective countermeasures against emerging infectious diseases require an understanding of transmission rate and basic reproduction number (R₀). R₀ for severe acute respiratory syndrome is generally considered to be >1, whereas that for Middle East respiratory syndrome (MERS) is considered to be <1. However, this does not explain the large-scale outbreaks of MERS that occurred in Kingdom of Saudi Arabia (KSA) and South Korean hospitals.

Aim: To estimate R₀ in nosocomial outbreaks of MERS.

Methods

R₀ was estimated using the incidence decay with an exponential adjustment model. The KSA and Korean outbreaks were compared using a line listing of MERS cases compiled using publicly available sources. Serial intervals to estimate R₀ were assumed to be six to eight days. Study parameters [R₀ and countermeasures (d)] were estimated by fitting a model to the cumulative incidence epidemic curves using Matlab.

Findings

The estimated R₀ in Korea was 3.9 in the best-fit model, with a serial interval of six days. The first outbreak cluster in a hospital in Pyeongtaek had an R₀ of 4.04, and the largest outbreak cluster in a hospital in Samsung had an R₀ of 5.0. Assuming a six-day serial interval, the KSA outbreaks in Jeddah and Riyadh had R₀ values of 3.9 and 1.9, respectively.

Conclusion

R₀ for the nosocomial MERS outbreaks in KSA and South Korea was estimated to be in the range of 2–5, which is significantly higher than the previous estimate of <1. Therefore, more comprehensive countermeasures are needed to address these infections.

The long-term relationship between dietary pantothenic acid (vitamin B5) intake and C-reactive protein concentration in adults aged 40 years and older

BACKGROUND AND AIMS

Low-grade inflammation, represented by minor C-reactive protein (CRP) elevation, has a critical role in the early stages of atherosclerosis, and pantothenic acid (PA) may have an antioxidant effect in inflammatory process. However, the long-term relationship between PA intake and CRP has not yet been studied. The objective of the present study was to evaluate the long-term relationship of PA intake to CRP concentration in healthy adults aged 40 years or older living in a rural area of South Korea.

METHODS AND RESULTS

A total of 908 subjects (349 men, 559 women) with repeated data on dietary PA intake and CRP concentration were included in the final analysis. To represent the long-term effect of PA intake, both PA intake at the baseline and average PA intake were used as the exposure, and CRP concentration at the third visit and its change from the baseline to the third visit were used as the outcome. After adjustment for potential confounders, a significant inverse relationship between PA intake and CRP concentration at the third visit was observed (P for trend = 0.001, β = -0.07 (P-value = 0.001) for PA _baseline; P for trend = <0.0001, β = -0.11 (P-value = 0.0004) for PA _{average (baseline, 2nd, 3rd)}). Higher PA intake was significantly related to lower or attenuated increase in CRP concentration (P for trend = 0.002, β = -0.24 (P-value = 0.002) for PA _baseline; P for trend = 0.001, β = -0.35 (P-value = 0.001) for PA _{average (baseline, 2nd, 3rd)}).

CONCLUSIONS

In conclusion, dietary PA intake was inversely related to subsequent CRP concentration in both men and women aged 40 years or older in South Korea.

Characteristics of pleural effusions in systemic lupus erythematosus: differential diagnosis of lupus pleuritis

We investigated the clinical characteristics of pleural effusion in systemic lupus erythematosus (SLE). A prospective analysis of 17 SLE patients with pleural effusion (seven lupus pleuritis, eight transudative effusions and two parapneumonic effusions) was performed. Thirty non-SLE patients with pleural effusion were recruited as controls. A pleural fluid ANA titer ≥1:160 was found in 8/17 (47.1%) SLE patients and none of the 30 non-SLE patients (p = 0.0001). Pleural fluid to serum C3 ratios were significantly lower in SLE than in non-SLE (median (minimum-maximum) 0.29 (0.03-0.43) versus 0.52 (0.26-0.73), p = 0.0002). Among SLE patients, pleural fluid ANA titers ≥1:160 were more frequently found in patients with lupus pleuritis than in those with pleural effusion from causes other than lupus itself (85.7% versus 20.0%, p = 0.0152). Serum CRP levels were significantly increased in patients with lupus pleuritis compared with SLE patients with transudative pleural effusion (2.30 (0.30-5.66) versus 0.7 (0.12-1.47) mg/dl, p = 0.0062). In conclusion, pleural fluid ANA titer and serum CRP levels are significantly increased in lupus pleuritis.

The association of radiographic progression with serum R-spondin 1 (RSPO1) levels or Dickkopf-1 (DKK1)/RSPO1 ratios in rheumatoid arthritis patients: clinical evidence for reciprocal inhibition between DKK1 and RSPO1

OBJECTIVES

To investigate the clinical implications of serum levels of R-spondin 1 (RSPO1), a natural antagonist for Dickkopf-1 (DKK1), and of DKK1/RSPO1 ratios in rheumatoid arthritis (RA) patients.

METHOD

Serum DKK1 and RSPO1 levels were measured in 102 RA patients and 39 age- and gender-matched healthy controls. In addition, DKK1 and RSPO1 levels were determined prior to and 3 months after anti-tumour necrosis factor alpha (anti-TNF-α) therapy in 15 RA patients. Clinical and laboratory data and baseline radiographs of the hands and feet were obtained. Serial radiographs were evaluated in 83 RA patients. Radiographic joint damage was assessed by the modified Sharp/van der Heijde score (SHS).

RESULTS

Serum RSPO1 levels were significantly reduced whereas serum DKK1 levels and DKK1/RSPO1 ratios were significantly increased in RA patients compared with controls (all p < 0.0001). Anti-TNF-α treatment significantly suppressed DKK1/RSPO1 ratios (p < 0.01). In contrast to DKK1 or RSPO1 levels, the ratios were significantly associated with erosive disease, elevated acute phase reactants, Disease Activity Score in 28 joints (DAS28) > 3.2, and radiographic progression rate (all p < 0.05). Although the RA patients with radiographic progression exhibited significantly increased DKK1 and reduced RSPO1 levels (p < 0.05), only the DKK1/RSPO1 ratio (log-transformed) was found to be a significant predictor of subsequent radiographic progression [odds ratio (OR) 2.07, p < 0.01].

CONCLUSIONS

In this study, the presence of RSPO1 in the circulation was shown for the first time. Our results suggest that the serum DKK1/RSPO1 ratio represents a better predictor of structural progression than either DKK1 or RSPO1 levels alone in RA patients.

Harmful and beneficial relationships between alcohol consumption and subclinical atherosclerosis

BACKGROUND AND AIMS

Arterial stiffness and increased intima-media wall thickness are two of the main predictors of cardiovascular disease (CVD). We evaluated whether brachial-ankle pulse wave velocity (baPWV) and common carotid artery intima-media wall thickness (CCA-IMT) are correlated with alcohol consumption in a cross-sectional study among Korean men and women aged 40 years and over.

METHODS AND RESULTS

All 5539 subjects (2121 men and 3418 women) were participants in the Multi-Rural Communities cohort (MRcohort) study, a part of the Korean Genome Epidemiology Study (KoGES). The baPWV was positively correlated with alcohol consumption in men (p for trend <0.0001). Age (middle-aged versus elderly) modified the effect of alcohol consumption on PWV. On the other hand CCA-IMT decreased with alcohol consumption in men. There was no favorable zone of alcohol consumption in terms of baPWV and CCA-IMT. Adjustment for lipid profiles substantially attenuated the relationship between alcohol consumption and CCA-IMT. There was no clear relation between alcohol consumption and baPWV/CCA-IMT in women.

CONCLUSIONS

Along with a linear harmful relationship between alcohol consumption and arterial stiffness in men there may also be a beneficial relationship between alcohol consumption and carotid intima-wall thickness. The effect of alcohol on arterial stiffness may be slightly stronger in elderly men, and the effect of alcohol on CCA-IMT may be mediated by lipid factors.

Costs of illness and quality of life in patients with systemic lupus erythematosus in South Korea

OBJECTIVE

To assess the costs of illness, health-related quality of life (HRQOL) and their associated factors in patients with systemic lupus erythematosus (SLE) in South Korea.

METHOD

Two hundred and one patients with SLE were enrolled at the Rheumatology clinic of Seoul National University Hospital. Direct, indirect and total costs and HRQOL were measured using hospital electronic data and face-to-face interview. Socio-demographic and clinical factors associated with cost of illness and HRQOL were analyzed using multiple regression and multivariate logistic regression.

RESULTS

The average total cost of illness was estimated to be KRW 9.82 million (US $ 8993) per year, of which 41.6% was accounted for by direct costs and 58.4% by indirect costs. In multivariate regression, patients with renal involvement and those with depression incurred an average increment in annual total costs of 37.6% (p = 0.050) and 49.1% (p = 0.024), respectively, and an average increment in annual direct costs of 26.4% (p = 0.050) and 43.3% (p = 0.002), respectively, compared with patients without renal involvement and depression, respectively. In addition, disease damage was positively associated with an average increment in annual total and direct costs (55.3%, p = 0.006; 33.3%, p = 0.013, respectively), and the occurrence of indirect costs (OR 2.21, 1.09-4.88). There was no significant difference in HRQOL between patients with and without renal involvement (0.655 vs. 0.693, p = 0.203) CONCLUSION: Renal involvement, depression, and disease damage were major factors associated with higher total and medical costs for patients with SLE in South Korea. Effective treatment of renal disorders and depression may reduce the high economic burden of SLE.

A cross-sectional analysis of the relationship between daily alcohol consumption and serum adiponectin levels among adults aged 40 years or more in a rural area of Korea

BACKGROUND/OBJECTIVES

Light-to-moderate alcohol consumption has been proposed to raise serum adiponectin levels, but this view is controversial. There is little information on the effect of heavy drinking. The aim of this study was to examine the relationship between alcohol consumption and serum adiponectin levels in healthy Koreans.

SUBJECTS/METHODS

The design of the study was cross-sectional, using data from the Korean Multi-Rural Communities Cohort Study (MRCohort), which is a part of the Korean Genome Epidemiology Study (KoGES). The subjects were 1542 individuals (635 men and 907 women) aged ≥ 40 years who were recruited in Yangpyeong-Gun, Kyunggi province, South Korea, in 2005 and 2006. Daily alcohol consumption was calculated from average frequency of alcohol consumption and the amount of alcohol consumed per occasion using a structured questionnaire and serum adiponectin levels were measured.

RESULTS

Although adiponectin levels appeared to be higher in those consuming moderate levels of alcohol than in nondrinkers, the difference was not statistically significant. Heavy drinking (≥ 90.0 g/day) was significantly related to reduced serum adiponectin levels (P=0.003), although the significance of the relationship was reduced after adjusting for potential confounders (P=0.061) such as age, waist/hip ratio, blood pressure, fasting blood glucose, current smoker, higher education, protein intake, vitamin C intake and vitamin E intake in men. The relation seemed to be stronger in individuals consuming alcohol in the form of takju (Korean rice wine; P=0.022).

CONCLUSIONS

Heavy alcohol drinking (≥ 90.0 g/day) may be related to lower serum adiponectin levels in Korean men.

Segregation of enlarged vestibular aqueducts in families with non-diagnostic SLC26A4 genotypes

BACKGROUND

Hearing loss with enlarged vestibular aqueduct (EVA) can be inherited as an autosomal recessive trait caused by bi-allelic mutations of SLC26A4. However, many EVA patients have non-diagnostic SLC26A4 genotypes with only one or no detectable mutant alleles.

METHODS AND RESULTS

In this study, the authors were unable to detect occult SLC26A4 mutations in EVA patients with non-diagnostic genotypes by custom comparative genomic hybridisation (CGH) microarray analysis or by sequence analysis of conserved non-coding regions. The authors sought to compare the segregation of EVA among 71 families with two (M2), one (M1) or no (M0) detectable mutant alleles of SLC26A4. The segregation ratios of EVA in the M1 and M2 groups were similar, but the segregation ratio for M1 was significantly higher than in the M0 group. Haplotype analyses of SLC26A4-linked STR markers in M0 and M1 families revealed discordant segregation of EVA with these markers in eight of 24 M0 families.

CONCLUSION

The results support the hypothesis of a second, undetected SLC26A4 mutation that accounts for EVA in the M1 patients, in contrast to non-genetic factors, complex inheritance, or aetiologic heterogeneity in the M0 group of patients. These results will be helpful for counselling EVA families with non-diagnostic SLC26A4 genotypes.

Identities and frequencies of mutations of the otoferlin gene (OTOF) causing DFNB9 deafness in Pakistan

Mutations in OTOF, encoding otoferlin, cause non-syndromic recessive hearing loss. The goal of our study was to define the identities and frequencies of OTOF mutations in a model population. We screened a cohort of 557 large consanguineous Pakistani families segregating recessive, severe-to-profound, prelingual-onset deafness for linkage to DFNB9. There were 13 families segregating deafness consistent with linkage to markers for DFNB9. We analyzed the genomic nucleotide sequence of OTOF and detected probable pathogenic sequence variants among all 13 families. These include the previously reported nonsense mutation p.R708X and 10 novel variants: 3 nonsense mutations (p.R425X, p.W536X, and p.Y1603X), 1 frameshift (c.1103_1104delinsC), 1 single amino acid deletion (p.E766del) and 5 missense substitutions of conserved residues (p.L573R, p.A1090E, p.E1733K, p.R1856Q and p.R1939W). OTOF mutations thus account for deafness in 13 (2.3%) of 557 Pakistani families. This overall prevalence is similar, but the mutation spectrum is different from those for Western populations. In addition, we demonstrate the existence of an alternative splice isoform of OTOF expressed in the human cochlea. This isoform must be required for human hearing because it encodes a unique alternative C-terminus affected by some DFNB9 mutations.

Lack of association between LTA and LGALS2 polymorphisms and myocardial infarction in Japanese and Korean populations

To investigate the recently reported associations of polymorphisms in lymphotoxin-alpha (LTA) and galectin-2 (LGALS2) with myocardial infarction (MI), we analyzed a single nucleotide polymorphism of LTA (LTA 252A>G in LTA intron 1) and that of LGALS2 (LGALS2 3279C>T in LGALS2 intron 1) in Japanese and Korean populations. Although significant associations with MI were not observed in either population, we found that LTA 252GG was significantly associated with the severity of the disease for both the Japanese and Korean populations (P=0.017 and P=0.001, respectively). On the other hand, the polymorphism of LGALS2 was not associated with the severity of coronary atherosclerosis. These observations showed that, while the LTA 252GG genotype might modify the development of coronary atherosclerosis, the relation of LTA and LGALS2 to MI itself remained much less certain.

Relationship between the change in overweight status from childhood to adolescence and metabolic syndrome phenotypes: a 9-year retrospective study

OBJECTIVE

To evaluate how the changes in overweight status from childhood to adolescence are related to metabolic syndrome phenotypes in adolescents.

SUBJECTS AND METHODS

A total 375 adolescents aged 16 years. The overweight status from childhood to adolescence (from 7 years of age to 16 years) was determined by body mass index (BMI, kg/m(2)) calculated from records of the School Physical Examination data. The change in body weight was classified into four groups: normal weight to normal weight (NW-NW); overweight to normal (OW-NW); normal to overweight (NW-OW); overweight to overweight (OW-OW). Metabolic syndrome phenotypes were examined from a cross-sectional survey.

RESULTS

The mean values of all phenotypes except for body fatness (BMI and waist) and the cluster score of phenotypes at 16 years of age were not different between the NW-NW group and the OW-NW group, nor between the NW-OW group and the OW-OW group. However, the score as well as the level of body fatness and blood glucose were significantly different between current overweight and normal adolescents regardless of overweight status during childhood (P<0.05).

CONCLUSION

There was a linear relationship between overweight status during childhood and metabolic syndrome phenotypes in adolescence but current overweight status (adolescence overweight) was more closely related to the adolescent risk of metabolic syndrome than childhood overweight status.

A seroprevalence study of poliovirus antibody among primary schoolchildren in Korea

We aimed to determine the seroprevalence of poliovirus antibody in Korea by using the cell culture neutralization method recommended by the WHO. A total of 500 sera collected from children at eight primary schools in Kyunggi province were used for this study. We found that 82.2% of children were positive for all three types of poliovirus and antibody-positive rates for types I, II and III were 94.4, 96.6 and 86.8% respectively, indicating that seropositive rates for types I and II were considerably higher than for type III (P<0.0001). This result implies that the type III component of the oral polio vaccine should be evaluated further. Although a greater number of children, including young infants, need to be tested for seroprevalence, this study still provides us with valuable information on the effectiveness of vaccination against polioviruses in Korea.

Rubella antibody loss rates in Korean children

We followed students in eight elementary schools for rubella antibody from 1993 to 1996 (602 pairs) and 1996-9 (588 pairs) in Gyeonggi Province, Korea. We tested rubella IgG and administered rubella vaccine to the children with the titres < 10 IU/ml. The loss rates of rubella IgG during the follow-up periods were 14.3 and 15.8%, respectively. Among vaccinated groups, the loss rate was 18.8%, which was significantly higher than 13.8% of the mixture of natural and vaccine-induced immunity groups. The group that had the lower preceding antibody titre had a higher loss rate of 24.8% compared to 7.2% for the group whose titre was 40 IU/ml or above. In a multivariate analysis, age and gender were not related to antibody loss rate. Under this higher rubella antibody loss rate, in order to prevent congenital rubella syndrome, the immunization for women at childbearing age appears necessary until rubella can be eliminated or controlled.

Preparation of alginate beads for floating drug delivery system: effects of CO(2) gas-forming agents

Floating beads were prepared from a sodium alginate solution containing CaCO(3) or NaHCO(3) as gas-forming agents. The solution was dropped to 1% CaCl(2) solution containing 10% acetic acid for CO(2) gas and gel formation. The effects of gas-forming agents on bead size and floating properties were investigated. As gas-forming agents increased, the size and floating properties increased. Bead porosity and volume average pore size, as well as the surface and cross-sectional morphology of the beads were examined with Mercury porosimetry and Scanning Electron Microscopy. NaHCO(3) significantly increased porosity and pore diameter than CaCO(3). Incorporation of CaCO(3) into alginate solution resulted in smoother beads than those produced with NaHCO(3). Gel strength analysis indicated that bead strength decreased with increasing gas-forming agent from 9 to 4 N. Beads incorporating CaCO(3) exhibited significantly increased gel strength over control and NaHCO(3)-containing samples. Release characteristics of riboflavin as a model drug were studied in vitro. Release rate of riboflavin increased proportionally with addition of NaHCO(3). However, increasing weight ratios of CaCO(3) did not appreciably accelerate drug release. The results of these studies indicate that CaCO(3) is superior to NaHCO(3) as a gas forming agent in alginate bead preparations. The enhanced buoyancy and sustained release properties of CaCO(3)-containing beads make them an excellent candidate for floating drug dosage systems (FDDS).

Multicenter study on the prevalence of perennial allergic rhinitis and allergy-associated disorders

Multicenter Study on the Prevalence of Perennial Allergic Rhinitis and Allergy-Associated Disorders This study was aimed to determine the prevalence of perennial allergic rhinitis (PAR) using the skin test, radioallergosorbent test (RAST), or multiple allergosorbent test (MAST) and to clarify the clinical aspects of the patients diagnosed as having PAR by the questionnaire survey and rhinologic examination. The 71,120 subjects who had visited the 23 otolaryngology clinics at the randomly selected tertiary referral hospitals in Korea between November 1, 1999 and April 30, 2000 were studied. PAR was diagnosed when subjects complained of two or more associated symptoms and the skin test, RAST, or MAST using perennial inhalant allergens was positive. The questionnaire survey and rhinologic examination were performed in subjects with PAR. The prevalence of PAR was 3.93%. We could find no significant difference in the prevalence of PAR between the two sexes. However, there was a significant difference in the prevalence of PAR between the child and adult groups. The chief complaints were, in order of decreasing frequency, nasal obstruction, watery rhinorrhea, and sneezing. There was a family history of PAR in 40.2% of the subjects. The 39.6% of the subjects had associated allergic diseases, being atopic dermatitis most common. In conclusion, the prevalence of PAR in tertiary referral hospitals in Korea is 3.93%. Many subjects with PAR have family history and appear to be associated with other allergic diseases.

Association between Helicobacter pylori infection and the risk of gastric cancer in the Korean population: prospective case-controlled study

BACKGROUND

Gastric cancer is still the most common malignant tumor in Koreans. Although many reports have supported the association of Helicobacter pylori infection and the development of gastric cancer, few studies have been adjusted by variable factors such as age. sex, education, and economic status. Furthermore, most results from areas with a high incidence of gastric cancer, such as China and Korea, have failed to document any relationship between H. pylori infection and gastric cancer. We conducted a prospective case-controlled study, with controls matched for and adjusted by age, sex, education, and economic status, to evaluate the causal relationship between H. pylori infection and gastric cancer in Korean people.

METHODS

From March 1997 to October 1998, 136 consecutive patients with gastric cancer, diagnosed by endoscopic histology, and 136 age- and sex-matched control subjects, confirmed to be free of gastric cancer by endoscopy during the same period, were enrolled in the study. The presence of H. pylori infection was determined by enzyme immunoassay (EIA) serology test.

RESULTS

Seventy-two of the 136 gastric cancer patients (53%) were positive for H. pylori infection and 54 of the 136 control subjects (40%) were positive for H. pylori infection. The odds ratio (OR), adjusted by variable risk factors, such as age, sex, education, and economic status, for gastric cancer in H. pylori-infected patients was 1.82 (95% confidence internal [CI], 1.10-3.00; P = 0.019). The age- and sex-matched OR by conditional logistic regression was 1.6 (95% CI., 1.01-2.53; P = 0.043).

CONCLUSIONS

H. pylori infection may be one of the important risk factors for the development of gastric cancer in Korea, an area of high prevalence of H. pylori infection and a high incidence of gastric cancer.

Clinical application of continent anal plug in bedridden patients with intractable diarrhea

PURPOSE

Some patients bedridden from various causes such as stroke or spinal cord injury experience poor control of bowel movement. This causes fecal leakage and diarrhea, increases the risk of perianal excoriation and bed sores, and is a burden on caregivers. To evaluate the efficacy of fecal evacuation and the prevention and treatment of skin complications in intractable diarrhea patients using a new device.

METHODS

A continent anal plug (US Patent No. 5 569 216) comprises an inner balloon surrounded by an outer balloon, both of which are mounted on a silicone tube containing a pair of air passages and an enema fluid inlet. The tube is secured in place in the rectum by the inflatable outer balloon and is designed to drain fecal matter through a thin collapsible hose situated in the anal canal. Thirty-two patients (21 male; median age 61 (range, 28-76) years) were evaluated after fully informed consent. Median duration was 12 (range, 3-37) days.

RESULTS

The continent anal plug evacuated efficiently in those patients with loose or watery stools who only required irrigation once daily or not at all. Skin excoriations improved in three to seven days. Minimal leakage was seen around the anus. There was no anorectal mucosal injury noted over 37 days.

CONCLUSIONS

The continent anal plug is an efficient method of treating patients with loss of bowel control and incontinence because it enables controlled fecal evacuation and helps reduce skin complications without causing anorectal mucosal injury.

A co-operative study: clinical characteristics of 334 Korean patients with moyamoya disease treated at neurosurgical institutes (1976-1994). The Korean Society for Cerebrovascular Disease

A co-operative study was conducted to determine the clinical characteristics of patients with moyamoya disease who were diagnosed and treated at neurosurgical institutes in Korea before 1995. Twenty-six hospitals contributed 505 cases and among them, the clinical characteristics of 334 patients with definite moyamoya disease were evaluated. The number of patients began to increase from the late 1980s, and after that approximately 20 patients were treated each year. There were two age peaks: from six to 15 and from 31 to 40 years of age. Haemorrhagic manifestations occurred in approximately 43% of the patients. The major clinical manifestations were haemorrhage in adults (62.4%) and ischaemia in children (61.2%). Overall 54.5% of the patients experienced decreased consciousness levels, mainly due to intracranial haemorrhage or cerebral infarction. In the patients with ischemic manifestations, the adult patients were more likely to have cerebral infarction than the pediatric patients (80% vs. 39%) and the pediatric patients were more likely to have TIA (61% vs. 25%). Thirty eight percent of the patients underwent bypass surgery and 53% of these procedures were performed bilaterally. Treatment policies, including indications for bypass surgery and commonly used drugs, were somewhat different according to the institution. Overall favorable outcome was 73%, and the most significant factor affecting poor outcome was haemorrhagic manifestation. This article describes the characteristics of 334 patients with moyamoya disease, who were diagnosed and treated at neurosurgical institutes in Korea before 1995.

Spinal intradural extramedullary capillary hemangioma: MR imaging findings

SUMMARY

Spinal intradural extramedullary capillary hemangiomas are extremely rare. We present the MR imaging and histologic findings in three patients with this abnormality. The three patients were men who had symptoms of either myelopathy (n = 2) or radiculopathy (n = 1). The tumors were well demarcated, 1.5-2.0 cm in diameter, and were located at the posterior or posterolateral portion of the thecal sac (one at the L1 level and the other two at the midthoracic level). On MR images, the tumor showed isointensity relative to the spinal cord on T1-weighted images, hyperintensity on T2-weighted images, and strong homogeneous enhancement on contrast-enhanced T1-weighted images in all three patients. In two patients, the dural tail sign was observed. Capillary hemangioma should be included in the differential diagnosis of a spinal intradural extramedullary tumor.

Improved imaging of hepatic metastases with delayed pulse inversion harmonic imaging using a contrast agent SH U 508A: preliminary study

To investigate the feasibility of delayed pulse-inversion harmonic imaging (PIHI) with the SH U 508A to improve imaging of hepatic metastases, we evaluated 20 patients with known hepatic metastases. Conventional ultrasound (US) was performed before administration, and PIHI was performed 5 min after a bolus injection of 4 G of microbubble contrast agent (300 mg/mL of SH U 508A). Intense, homogeneous enhancement in the liver parenchyma was seen in all patients on delayed PIHI. In 10 patients (50%), 1 or more focal liver lesions that were not seen on unenhanced imaging were detected on delayed PIHI. When comparing 55 lesions that were seen on both techniques, delayed PIHI was superior to unenhanced imaging in terms of lesion conspicuity and lesion-to-liver contrast (p < 0.001, respectively). Delayed PIHI with SH U 508A can improve conspicuity of hepatic metastases and reveal focal liver lesions that are not detected on unenhanced imaging.

A 3'-5' exonuclease in human leukemia cells: implications for resistance to 1-beta -D-arabinofuranosylcytosine and 9-beta -D-arabinofuranosyl-2-fluoroadenine 5'-monophosphate

A 3'-5' exonuclease that excises the nucleotide analogs 1-beta-d-arabinofuranosylcytosine monophosphate and 9-beta-d-arabinofuranosyl-2-fluoroadenine 5'-monophosphate incorporated at 3' ends of DNA was purified from the nuclei of: 1) primary human chronic lymphocytic leukemia cells, 2) primary and established human acute myeloblastic leukemia cells, and 3) lymphocytes obtained from healthy individuals. The activity of this nuclear exonuclease (exoN) is elevated approximately 6-fold in 1-beta-d-arabinofuranosylcytosine-resistant leukemia cells as compared with drug-sensitive cells, and it differs between two healthy individuals and among three leukemia patients. exoN is a 46-kDa monomer, requires 50 mm KCl and 1 mm magnesium for optimal activity, and shows a preference for single-stranded over duplex DNA. Its physical and enzymatic properties indicate that exoN is a previously uncharacterized enzyme whose activity may confer resistance to clinical nucleoside analogs in leukemia cells.

Substrate specificity of the p53-associated 3'-5' exonuclease

p53 exhibits 3'-5' exonuclease activity and the significance of this biochemical function is currently not defined. In order to gain information about the potential role(s) of this exonuclease activity, recombinant and wild-type human p53 was examined for excision of nucleotides from defined synthetic DNA substrates. p53 removes nucleotides threefold faster from single-strand DNA than from DNA duplexes, exhibits a 1.5-fold preference for 3'-terminals of DNA that contain a single nucleotide mispair (mismatch) as compared to correctly paired DNA and efficiently excises nucleotides from 3'-ends of blunt and cohesive (staggered) DNA double-strand breaks. The p53 exonuclease is predominantly non-processive on DNA which is 17 nucleotides long (or shorter) and processive on the longer 30-mers. The processivity of nucleotide excision is decreased in the presence of 50 mM potassium phosphate and eliminated when full-length p53 is replaced with the core domain, comprised of amino acids 82-292. Photoaffinity labeling indicates that (1) p53 monomers, rather than dimers, bind to single-strand forms of these oligomers; (2) complexes between p53 and 30-mers are more stable than those formed with 17-mers. The stability of these complexes determines processivity during nucleotide removal and modulates the 3'-5' exonuclease activity of p53. The relevance of substrate specificity of the p53 exonuclease to DNA repair is discussed.

The changing epidemiology of hepatitis A in children and the consideration of active immunization in Korea

Currently, Korea is a low endemicity country for HAV, especially in children. However, recent reports of hepatitis A outbreaks show that there has been a shift of disease incidence to adolescents and young adults, with 2 cases of acute liver failure in one reported outbreak. We need to study the immune status for HAV in order to provide information for the establishment of preventive measures and possible consequences of HAV in Korea. A total of 334 infants, children and adolescents less than 20 years of age living in rural areas of Kyonggi Province, Korea were evaluated for anti-HAV immune status in 1996. Five hundred and eighty-four primary school children living in the same area were separately evaluated for the natural seroconversion rate between 1993 and follow-up samples taken in 1996. Anti-HAV IgG antibody was measured by enzyme immunoassay (HAVAB EIA kit, Abbott Laboratories, Chicago, Illinois, USA). In comparison with previous reports of seroprevalence rates, our data confirmed a dramatic drop in seroprevalence rates among children and adolescents under 20 years of age living in rural areas, from over 63.8% two decades ago to 4.6% in 1996. Natural acquisition of HAV antibody in primary school children rarely occurs, registering only 0.5% during three years. Several outbreaks in young adults during 1996-1998 suggested that immunity against HAV in this population is so low that massive outbreaks are unavoidable. Teenagers and young adults, especially soldiers, who are likely to be exposed to contaminated food or water, would also have a greater risk of hepatitis A. Immunizing children with HAV vaccine as a routine schedule should also be considered in Korea in the future, particularly if the disease burden could be estimated and the cost-effectiveness of the vaccine could be proved.

Clofilium, a potassium channel blocker, induces apoptosis of human promyelocytic leukemia (HL-60) cells via Bcl-2-insensitive activation of caspase-3

We have demonstrated that clofilium, a potassium channel blocker, induces apoptosis on human promyelocytic leukemia (HL-60) cells. Cells treated with clofilium led to suppression of viability and proliferation in both time and concentration-dependent manners. Nuclear DAPI staining and electronmicroscopic examination revealed typical nuclear features of apoptosis in cells treated with clofilium that was further verified in DNA fragmentation analysis. Flow cytometry analysis with FITC-annexin V and propidium iodide (PI) revealed that apoptotic cell population with Annexin V+/PI- increased gradually from < 2% at 0 h, to 20% at 4 h and 29% at 16 h after exposure to 10 microM clofilium in HL-60 cells. Furthermore, fluorometric immunosorbent enzyme assay for activity of caspase-3 showed approximately a 10-fold increase of activity in cells treated with 10 microM of clofilium for 2-3 h compared with the basal level of its activity in untreated control cells. Immunoblotting analysis revealed proteolytic cleavage of caspase-3 and subsequent cleavage of PARP. However, there was no significant change of Bcl-2 and Bax proteins. These results indicate that clofilium exerts antiproliferative action and growth inhibition on HL-60 through induction of apoptosis which is mediated via Bcl-2-insensitive activation of caspase-3, and suggest chemotherapeutic and cytostatic potentials of this compound in human leukemias.

Expression of cell-cycle regulators, cyclin E and p21WAF1/CIP1, potential prognostic markers for gastric cancer

AIMS

The deregulation of cyclin, cyclin-dependent kinases (CDKs) and their inhibitors could have a crucial role in the development of diverse human cancers.

METHODS

In this study, we analysed the expression of cyclin D1, cyclin E, p21WAF1/CIP1 and p27KIP1 in 84 surgically resected gastric cancers by immunohistochemistry with long-term follow-up (median 38 months). We also evaluated the relation between each cell cycle regulator and various clinicopathological findings, including age, sex, histological grade, tumour location, tumour type and stage and lymph-node metastasis.

RESULTS

Overexpression of cyclin D1 and E was detected in 21/84 (25%) and 34/84 (40.5%) patients, respectively. Normal gastric epithelium showed consistently positive immunostain for p21WAF1/CIP1 and p27KIP1 in more than 50% of nuclei. Loss of p21WAF1/CIP1 and p27KIP1 expression was noted in 45/84 (53.6%) and 44/84 (52.4%) patients, respectively. Among the various clinicopathological findings, overexpression of cyclin E was associated with lymph-node metastasis (P=0.003) and recurrence (P=0.043). Loss of p21WAF1/CIP1 expression was more frequent in diffuse type cancers (P=0.005) and was correlated with recurrence (P=0.002) and death (P=0.002). Overexpression of cyclin E and loss of p21WAF1/CIP1 expression were significantly correlated with decreased disease-free (P=0.037; P= 0.001) and overall (P=0.031; P=0.001) survival.

CONCLUSIONS

These results suggest that immunohistochemical analysis for cell cycle regulators, especially cyclin E and p21WAF1/CIP1, might be a useful prognostic indicator in gastric cancer.

Anterior clinoid process and optic strut in Koreans

The anterior clinoid process and the optic strut are often removed during operation on the anterior part of the cavernous sinus. Therefore it is important for neurosurgeons to verify their dimensions and variations. The purpose of this study was to investigate the dimension and the variation of the anterior clinoid process and to describe the locational variation of the optic strut. Seventy-three skulls of Korean adults were used. The average length, basal width and thickness of the anterior clinoid process were 9.18 +/- 1.55, 9.63 +/- 1.49 and 5.32 +/- 1.07 mm, respectively. The average thickness of the optic strut was 2.9 +/- 1.15 mm and it was commonly attached to anterior two-fifths of the anterior clinoid process. The complete caroticoclinoid canal was observed in 4.1%, however it was incomplete in 11.6%. The incidence of a caroticoclinoid canal in Koreans was relatively low compared with other races.

Correlation between the postmortem stature and the dried limb-bone lengths of Korean adult males

The postmortem stature was measured in 57 Korean adult males (age range: 20-86 years old, mean: 52.3 years old) in supine position. After dissection of the corpses, we measured the maximum length of the remaining limb-bones (humerus, radius, ulna, femur, tibia and fibula). The correlation coefficients between the stature and each limb-bone length were calculated. Simple regression equations for estimating stature from each limb-bone length and multiple regression equations from the combination of limb-bone lengths were also obtained.

Study on the Korean adult cranial capacity

Cranial capacity was measured in Korean adult skulls. The cavity was filled with rice seeds and the volume of the seeds were measured in a graduated cylinder. The results were 1470 +/- 107 (mean +/- standard deviation) in male and 1317 +/- 117 cc in female skulls. These values were in good accordance with those previously reported. In addition, regression formulae were obtained with the product of the length, breadth, and height of the skull as an independent parameter and the measured capacity as a dependent one. With known external measurements, the expected cranial capacity was as follows: when using baso-bregmatic height, male: capacity = 307.5 + 333 x 10(-6) x (length.breadth.baso-bregmatic height) female: capacity = -12.0 + 435 x 10(-6) x (length.breadth.baso-bregmatic height) and, when using auriculo-bregmatic height, male: capacity = 214.6 + 429 x 10(-6) x (length.breadth.auriculo-bregmatic height) female: capacity = 131.6 + 461 x 10(-6) x (length.breadth.auriculo-bregmatic height).

Sexual response of Saccharomyces cerevisiae: phosphorylation of yeast glyoxalase I by a cell extract of mating factor-treated cells

The phosphorylation of glyoxalase I was observed when the phosphatase-treated enzyme was incubated in the presence of [gamma-32P]ATP and a cell extract prepared from alpha-type yeast cells which had been treated with the culture supernatant of a-type yeast cells. The phosphorylated protein was identified as glyoxalase I by using anti-glyoxalase I rabbit immunoglobulin G.