Jung Mook Kang

Development of novel algorithm and real-time monitoring ambulatory system using Bluetooth module for fall detection in the elderly

Novel algorithm and real-time ambulatory monitoring system for fall detection in elderly people is described. Our system is comprised of accelerometer, tilt sensor and gyroscope. For real-time monitoring, we used Bluetooth/spl trade/. Accelerometer measures kinetic force, tilt sensor and gyroscope estimates body posture. Also, we suggested algorithm using signals which obtained from the system attached to the chest for fall detection. To evaluate our system and algorithm, we experimented on three people aged over 26 years. The experiment of four cases such as forward fall, backward fall, side fall and sit-stand was repeated ten times and the experiment in daily life activity was performed one time to each subject. These experiments showed that our system and algorithm could distinguish between falling and daily life activity. Moreover, the accuracy of fall detection is 96.7%. Our system is especially adapted for long-time and real-time ambulatory monitoring of elderly people in emergency situation.

Prevalence and risk factors of Helicobacter pylori infection in Korea: Nationwide multicenter study over 13 years

BackgroundThe aim of this study was to evaluate the time trend of seropositivity of Helicobacter pylori (H. pylori) over the period of 13 years in an asymptomatic Korean population, and investigate associated risk factors.MethodsThis cross-sectional nationwide multicentre study surveyed anti-H. pylori IgG antibodies in 19,272 health check-up subjects (aged [greater than and equal to]16 years) in 2011. Risk factors for H. pylori infection were investigated using logistic regression. Seropositivity in asymptomatic subjects without H. pylori eradication was compared between the years 1998 and 2005. Birth cohort effects were also evaluated.ResultsAfter exclusion of subjects with a history of H. pylori eradication therapy (n = 3,712, 19.3%) and gastric symptoms (n = 4,764, 24.7%), the seroprevalence of H. pylori infection was 54.4% in 10,796 subjects. This was significantly lower than the seroprevalence of 59.6% in 2005 and that of 66.9% in 1998, and this decrease of seropositivity of H. pylori became widespread across all ages and in most areas of the country. This decreasing trend could be explained by cohort analysis. All younger birth cohorts had a lower seroprevalence of H. pylori than older birth cohorts at the same age. Decreased seroprevalence within the same birth cohorts also accounted for this phenomenon. Clinical risk factors of H. pylori infection were higher cholesterol level ([greater than and equal to] 240 mg/dl) (OR = 1.33; 95% CI = 1.14-1.54), male gender, older age, low income, and residence in a rural area.ConclusionsA decreasing trend of H. pylori seroprevalence due to a birth cohort effect requires further studies on its related human host factors as well as socio-economic and hygienic factors. In addition, the relationship between H. pylori infection and high cholesterol level needs more investigation regarding underlying pathogenesis.

The Effects of Genetic Polymorphisms of il-6 , il-8 , and il-10 on helicobacter pylori- induced Gastroduodenal Diseases in Korea

Background The genes that encode proinflammatory and anti-inflammatory cytokines are good candidate markers of host susceptibility to gastroduodenal disease. The present study was performed to evaluate whether or not the genetic polymorphisms of IL-6, IL-8, and IL-10 are associated with gastroduodenal disease in the Korean population. Methods This study enrolled 1187 patients, including controls, those with gastric cancer (GC), benign gastric ulcer (BGU), and duodenal ulcer patients. Six polymorphisms were genotyped, 3 of IL-10 (at −592, −819, and −1082), 1 of IL-8 (at −251), and 2 of IL-6 (at −174 and −572), by polymerase chain reaction-restriction fragment length polymorphism analysis. Results The frequency of IL-10-1082 G carriers was higher in cases of a diffuse type GC [odds ratio (OR) 1.8, 95% confidence interval (CI): 1.0-3.1, P=0.041] or BGU (OR 1.6, 95% CI: 1.0-2.5, P=0.040), than in the control group regardless of Helicobacter pylori infection. The IL-8-251 A/A genotype was more common in H. pylori-positive patients with GC (OR 2.0, 95% CI: 1.2-3.6, P=0.013) or BGU (OR 2.7, 95% CI: 1.5-4.8, P=0.001) than in H. pylori-positive controls. In addition, the frequencies of IL-6-572 G/G (OR 0.3, 95% CI: 0.1-0.9, P=0.027) and of G carriers (OR 0.5, 95% CI: 0.4-0.8, P=0.003) were lower in H. pylori-positive duodenal ulcer patients than in H. pylori-positive controls. IL-10-592 C/C (OR 0.4, 95% CI: 0.2-0.9, P=0.028) was an independent factor associated with a decreased risk of the intestinal type of GC by multivariate analysis. Furthermore, a synergistic effect was observed between IL-10-592 A/A and IL-8-251 A/A with respect to the development of GC or BGU. Conclusions These results suggest that the genetic polymorphisms of these 3 inflammation-related cytokines, IL-10, IL-8, and IL-6, are associated with the development of H. pylori-associated gastroduodenal disease.

The Role of Serum Pepsinogen and Gastrin Test for the Detection of Gastric Cancer in Korea

Background and Aim:  This study was performed to determine whether serum pepsinogen (PG) and gastrin testing can be used to detect gastric cancer in Korea.

Second‐Line Treatment for Helicobacter pylori Infection: 10‐day Moxifloxacin‐Based Triple Therapy versus 2‐week Quadruple Therapy

Background and aim:  The aim of this study was to test the efficacy of 10‐day moxifloxacin‐based triple therapy versus 2‐week quadruple therapy for the second‐line treatment of Helicobacter pylori infection.

Effect of aging on gastric mucosal defense mechanisms: ROS, apoptosis, angiogenesis, and sensory neurons.

Aging changes in the stomach lead to a decreased capacity for tissue repair in response to gastric acid. The aim of this study was to determine the mechanism associated with the increased susceptibility to injury of aging mucosa including reactive oxygen species (5), apoptosis, angiogenesis, and sensory neuron activity. Fischer 344 rats at four different ages (6, 31, 74 wk, and 2 yr of age) were studied. The connective tissue indicators [salt-soluble collagen and sulfated glycosaminoglycan (sGAG)], lipid hydroperoxide (LPO), myeloperoxidase (MPO), and hexosamine were assessed. We also evaluated the expression of early growth response-1 (Egr-1), phosphatase and tension homologue deleted on chromosome 10 (PTEN), caspase-9 (index of apoptosis), VEGF (index of angiogenesis), calcitonin gene-related peptide (CGRP, index of sensory neurons), and neuronal nitric oxide synthase (nNOS). The histological connective tissue area in the lower part of rat gastric mucosa increased with aging, with increase of salt-soluble collagen and sGAG. LPO and MPO in old rats were significantly greater than in the young rats, whereas hexosamine was significantly reduced. The old gastric mucosa had increased expression of Egr-1, PTEN, and caspase-9, whereas the VEGF, CGRP, and nNOS expression were significantly reduced. These results indicate that the lower part of rat gastric mucosa was found to be replaced by connective tissue with accumulation of oxidative products with aging. In addition, impairment of apoptosis, angiogenesis, and sensory neuron activity via the activation of Egr-1 and PTEN might increase the susceptibility of gastric mucosa to injury during aging.

Effect of the CYP2C19 polymorphism on the eradication rate of Helicobacter pylori infection by 7-day triple therapy with regular proton pump inhibitor dosage

Background and Aim:  Proton pump inhibitors (PPI) are mainly metabolized by cytochrome P450 2C19 (CYP2C19) in the liver. We investigated whether the CYP2C19 genotype plays a role in the eradication rate of Helicobacter pylori (H. pylori) infection in patients receiving pantoprazole‐ or esomeprazole‐based triple therapy.

CDX1 and CDX2 Expression in Intestinal Metaplasia, Dysplasia and Gastric Cancer

Intestinal metaplasia (IM) has been regarded as a premalignant condition. However, the pathogenesis of IM is not fully understood. The aim of this study was to evaluate the role of CDX1 and CDX2 in the formation of IM and the progression to dysplasia and gastric cancer (GC). A total of 270 subjects included 90 with GC, dysplasia and age- and sex-matched controls. Real-time PCR (RT-PCR) was performed with body specimens for CDX1 and CDX2. The expression of CDX2 was significantly higher in H. pylori positive group than H. pylori negative group (P = 0.045). CDX1 and CDX2 expression increased proportional to the IM grade of the body (P < 0.001). CDX2 expression was significantly higher in incomplete type of IM than in complete type (P = 0.045). The expression of CDX1 in dysplasia group was significantly higher than in the control group (P = 0.001); in addition, CDX1 and CDX2 in cancer group was significantly higher than control group (P < 0.001, and P < 0.001, respectively). Aberrant expression of CDX1 and CDX2 correlated with H. pylori infection and grade of IM in the body. Furthermore, the results suggest that CDX1 and CDX2 play a role in the progression to GC and dysplasia.

Prospective evaluation of a new stool antigen test for the detection of Helicobacter pylori, in comparison with histology, rapid urease test, 13C-urea breath test, and serology

Background and Aims:  This study aimed to evaluate the efficacy of a new polyclonal enzyme immunoassay for the detection of Helicobacter pylori (H. pylori) antigen in stool by determination of the optimal cut‐off value in the screening population.

Clinical meaning of pepsinogen test and Helicobacter pylori serology in the health check-up population in Korea

Objective This study was performed to assess the affects of age, sex, and Helicobacter pylori status on pepsinogen testing for atrophic gastritis and to establish the clinical implications of pepsinogen test results and H. pylori serology in a Korean population presenting for a health check-up. Methods Serum pepsinogen (PG) I and PG II, and H. pylori IgG were measured in 1485 adults. The PG values were analyzed based on age, sex, and H. pylori status, and the cutoff value for atrophic gastritis was determined. Results Serum PG I (sPGI) and sPGII were higher in H. pylori positive than in H. pylori negative individuals (sPGI, 56.3 vs. 42.2 μg/l, P<0.001; sPGII, 17.5 vs. 8.0 μg/l, P<0.001). The PG I/II ratio was lower in H. pylori positive than in H. pylori negative individuals (3.7 vs. 6.0, P<0.001). The sPGII and PG I/II ratio had a positive (r=0.132, P<0.001) and negative correlation with age (r=−0.229, P<0.001), respectively. Men had a higher sPGI (54.7 μg/l) than did women (48.4 μg/l) (P<0.001) but the PG I/II ratio was not statistically different and neither the atrophic gastritis. The PG I/II cutoff value for atrophic gastritis was 6.0 for H. pylori negative and 3.0 for H. pylori positive individuals. sPGI and sPGII were, however, not specific for atrophic gastritis. Conclusion The H. pylori IgG status, age, and sex were associated with the serum PG levels. To increase the efficacy of the PG I/II ratio for the detection of atrophic gastritis, the cutoff value of the PG I/II ratio should be stratified according to the H. pylori IgG status in the Korean population presenting for a health check-up.