Young Hwangbo

An adequate level of training for technical competence in screening and diagnostic colonoscopy: a prospective multicenter evaluation of the learning curve

BACKGROUND Various training programs in colonoscopy recommend that trainees should perform at least 100 to 200 procedures to be considered technically competent at diagnostic colonoscopy. OBJECTIVE Our purpose was to determine the adequate level of training for technical competence in screening and diagnostic colonoscopy. DESIGN A prospective multicenter trial. SETTING Fifteen tertiary care academic medical centers. PATIENTS Over 8 months we prospectively evaluated the procedures of 24 first-year GI fellows in 15 tertiary care academic medical centers. A total of 4351 colonoscopies were assessed prospectively with variable clinical factors. INTERVENTION Cecal intubation was documented by photographing the identified cecal landmarks, including the appendiceal orifice and the ileocecal valve. MAIN OUTCOME MEASUREMENTS Acquisition of competence (success rate) was evaluated for colonoscopic training on the basis of 2 objective criteria: (1) adjusted completion rate (>90%) and (2) cecal intubation time (<20 minutes). RESULTS The overall success rate was 83.5% (3635/4351). The mean cecal intubation time was 9.23 +/- 4.63 minutes. The success rate significantly improved and reached the requisite standard of competence after 150 procedures (71.5%, 82.6%, 91.3%, 94.4%, 98.4%, and 98.7%, respectively, for every 50 consecutive blocks). The polyp detection rate did not improve significantly during the 8 months and was not correlated with the learning curve. In addition, mean time to cecal intubation decreased significantly, from 11.16 to 8.39 minutes, after 150 procedures. Logistic regression analysis found that prolonged cecal intubation was caused by the following factors: elderly patients, female sex, low body mass index, poor bowel preparation, poor American Society of Anesthesiologists status, abdominal pain as an indication, instructors supervision, and low case volume. LIMITATIONS We did not record final pathologic reports of detected polyps and withdrawal time. CONCLUSIONS Competence in technically efficient screening and diagnostic colonoscopy generally requires experience with more than 150 cases. Also, factors associated with prolonged cecal intubation for typical trainees did not differ from those for experienced colonoscopists.

Increased levels of plasma brain-derived neurotrophic factor (BDNF) in children with attention deficit-hyperactivity disorder (ADHD)

BACKGROUND Recent reports have suggested a pathophysiological role of brain-derived neurotrophic factor (BDNF) in attention deficit-hyperactivity disorder (ADHD). We evaluated the plasma levels of BDNF in patients with ADHD. METHODS Plasma BDNF levels were measured in 41 drug naive ADHD patients and 107 normal controls. The severity of ADHD symptoms was determined by patient scores on the ADHD rating scale (ARS) and the computerized ADHD diagnostic system (ADS). RESULTS ANCOVA with age and gender as covariates showed that the mean plasma BDNF levels were significantly higher in ADHD patients than in normal controls (F=16.968, p<0.001). There were also significant differences in plasma BDNF levels of ADHD patients and those of normal controls for males and females (Mann-Whitney U-test, p=0.001 and 0.041, respectively). We also found a significant correlation between plasma BDNF levels and omission errors in ADS outcome-variable T-scores (p<0.001). CONCLUSIONS Our study suggests that there is an increase of plasma BDNF levels in untreated ADHD patients, and that plasma BDNF levels had a significant positive correlation with the severity of inattention symptoms. Further studies are required to elucidate the source and role of circulating BDNF in ADHD.

Cross-sectional study of blood lead effects on iron status in Korean lead workers

OBJECTIVE This study assessed the iron status of Korean male lead workers by measuring the dietary iron intake and biochemical indices, and tested the hypothesis that a high blood lead level is associated with impaired iron function, which results in higher prevalence of iron deficiency when the route of exposure is not the gastrointestinal tract. METHODS One hundred eighteen lead workers and 42 non-lead workers were recruited from mandatory annual health surveillance sites for industrial workers. Blood lead, hemoglobin, and hematocrit levels were evaluated as hematologic parameters, and serum iron concentrations, total iron-binding capacity, and percentage of transferrin saturation were evaluated as iron-status parameters. Dietary iron intake was assessed by a 24-h recall method. RESULTS Lead workers had significantly lower hemoglobin, hematocrit, serum iron levels, percentage of transferrin saturation, and dietary iron intake than did non-lead workers, and they had significantly higher (P < 0.01) total iron-binding capacity. The occurrence of iron-deficiency cases, as assessed by hematocrit values, was significantly higher (P < 0.001) in lead workers than in non-lead workers, and the prevalence of iron deficiency was associated with high blood lead levels (P = 0.033). The dietary iron intake was inversely associated with zinc protoporphyrin (P = 0.032). CONCLUSIONS This study confirmed the adverse effects of high blood lead levels on hematologic pathways and the effectiveness of dietary iron intake as a secondary preventive intervention against lead toxicity. To promote health and to prevent toxic effects of lead exposure in Korean lead workers, an adequate intake of dietary iron is strongly recommended.

Differences in radiological/HRCT findings in eosinophilic bronchitis and asthma: implication for bronchial responsiveness

Background: Airway hyperresponsiveness in asthmatics is considered to be one of the major consequences of airway inflammation and remodelling. Airway responsiveness is normal in patients with eosinophilic bronchitis (EB), despite eosinophilic inflammation of the airways comparable to that which occurs in asthmatics. Comparisons between asthma and EB should clarify the changes in airway morphology that are related specifically to AHR in asthmatics. Methods: Eighteen asthmatic patients, 15 patients with EB, and 11 healthy subjects were recruited. Airway wall area percentage (WA%), centrilobular prominence, and air trapping were compared using thin slice section computed tomography. Results: WA% was significantly greater in asthmatics than in patients with EB (72 (3.1)% v 54 (2.1)%, p = 0.032) and was similar in EB patients and controls (54 (2.1)% v 57 (1.8)%, p>0.05). Centrilobular prominence and air trapping were similar in EB patients and asthmatics and were significantly greater than in controls. Conclusion: WA% rather than air trapping or centrilobular prominence may be associated with the airway hyperresponsiveness that occurs in asthmatics but not in patients with EB.

Association between Intracellular Infectious Agents and Schizophrenia.

Objective A number of studies have reported association between Toxoplasma gondii (T. gondii) and Chlamydia infection and the risk of schizophrenia. The aim of the present study was to compare the prevalence of T. gondii and Chlamydia infection between the schizophrenia and normal control subjects and to compare the clinical features between seropositive and seronegative schizophrenia patients. Methods The rate of serum reactivity to T. gondii, Chlamydia trachomatis (C. trachomatis), Chlamydia pneumonia in 96 schizophrenia and 50 control subjects was investigated using enzyme-linked immunosorbent assay and indirect fluorescent antibody technique. The clinical symptoms of the schizophrenia patients were scored with Positive and Negative Syndrome Scale and a comparative analysis was carried out. Results A significant positive association between immunoglobulin G (IgG) antibodies to T. gondii and C. trachomatis in schizophrenia was found, and the odds ratio of schizophrenia associated with IgG antibody was found to be 3.22 and 2.86, respectively. The Toxoplasma-seropositive schizophrenia patient had higher score on the negative subscale N1 and N7 and general psychopathology subscale G13, while C. trachomatis-seropositive schizophrenia patient had higher score on the general psychopathology subscale G10. Conclusion The results from the present study suggest significant association between T. gondii, C. trachomatis infection and schizophrenia. In future, further studies are needed to elucidate the correlation between the two types of infection and schizophrenia.

Increased levels of plasma glial-derived neurotrophic factor in children with attention deficit hyperactivity disorder

Abstract Background: Recent evidence suggests that neurotrophic growth factor systems, including brain-derived neurotrophic factor, might be involved in the pathophysiology of attention deficit hyperactivity disorder (ADHD). Glial cell line-derived neurotrophic factor (GDNF) is from the transforming growth factor-β family and is abundantly expressed in the central nervous system, where it plays a role in the development and function of hippocampal cells. To date, no association studies have been done between ADHD and GDNF. Thus, here we investigate the hypothesis that there are differences in plasma GDNF levels between children with ADHD and healthy controls. Methods: Plasma GDNF levels were measured in 86 drug-naïve children with ADHD and 128 healthy children. The severity of ADHD symptoms was determined by scores on the Korean ADHD Rating Scale (K-ARS) in patients and healthy controls. Results: The median plasma GDNF levels in ADHD patients was 74.0 (IQR: 23.4–280.1) pg/ml versus 24.6 (IQR: 14.5–87.3) pg/ml in healthy controls; thus the median plasma GDNF levels in ADHD patients were significantly higher than in healthy controls (Mann–Whitney U-test, P < 0.01). Plasma GDNF levels were correlated positively with K-ARS subscale scores (inattention, hyperactivity–impulsivity and total), determined by Spearmans correlation test in ADHD patients and healthy controls (r = 0.371, P < 0.01; r = 0.331, P < 0.01; and r = 0.379, P < 0.01, respectively). Conclusions: These findings suggest increased plasma GDNF levels in untreated ADHD patients. In addition, plasma GDNF levels had a significant positive correlation with inattention, hyperactivity–impulsivity and K-ARS total scores in ADHD patients and healthy controls. Further studies are required to determine the source and role of circulating GDNF in ADHD.

Association between weekend catch-up sleep duration and hypertension in Korean adults

OBJECTIVE Our objective was to investigate if weekend catch-up sleep is independently related to a decrease in the risk for hypertension in Korean adults. METHODS The subjects included 2782 Korean adults ages 19 years and older. Data on demographic variables, sleep duration (weekday and weekend), and hypertension were obtained using questionnaires. Logistic regression analyses were performed to test the association between hypertension and sleep duration (weekday and weekend catch-up sleep duration); we also adjusted for possible covariates. RESULTS After adjustment for confounding variables, we found that individuals who slept less than 6 hours a night had an increased odds ratio (OR) for hypertension (OR, 1.73; 95% confidence interval [CI], 1.13-2.64) compared to individuals who slept 7 to <8 hours a night. Furthermore, one hour of weekend catch-up sleep was significantly associated with decreased risk for hypertension (OR, 0.83; 95% CI, 0.72-0.95). There were significant differences for groups with and without subjective sleep insufficiency in the association between weekend catch-up sleep duration and the prevalence of hypertension; in addition, the effect of an extra hour of weekend catch-up sleep per night on hypertension was stronger in those subjects who experienced subjective sleep insufficiency (OR, 0.61; 95% CI, 0.46-0.82). CONCLUSIONS Sleeping more on the weekend to compensate for weekday sleep deficit could lower the risk for hypertension in Korean adults, especially in Korean adults who have the subjective symptom of sleep insufficiency.

Sacroiliitis Is Common in Crohn's Disease Patients with Perianal or Upper Gastrointestinal Involvement

BACKGROUND/AIMS Sacroiliitis (SI) is one of the most frequent extraintestinal manifestations in inflammatory bowel disease (IBD) patients, but the exact prevalence has not been evaluated in Asia. There are few data on the association between SI and other clinical features of IBD. The prevalence of SI was evaluated using computed tomography (CT) and the phenotypic parameters associated with SI in Korean IBD patients were determined. METHODS Eighty-two patients with ulcerative colitis (UC) and 81 patients with Crohns disease (CD) were evaluated clinically. The presence of SI was evaluated using bone window setting of abdomino-pelvic CT images by two radiologists. RESULTS The prevalence rates of SI were 12.2% and 21.0% in the UC and CD groups, respectively. There was no relationship between the localization or extent of intestinal inflammation and the presence of SI in the UC group. Multivariate analyses confirmed that perianal and upper-gastrointestinal (from the mouth through to the jejunum) diseases were associated with the occurrence of SI in the CD group (p=0.026 and p=0.047, respectively). CONCLUSIONS SI was as common among Korean IBD patients as among Western patients. Perianal or upper-gastrointestinal involvement is associated with SI in CD patients.

Air trapping is a major determinant of persistent airway obstruction in asthmatics

Chronic persistent airway obstruction has been observed in moderate-to-severe asthmatics despite treatment with inhaled corticosteroids. We investigated which airway changes were associated with this obstruction. High-resolution computed tomography (HRCT) was performed at study entry and reexamined at the time of follow-up when the FEV1 reached a maximally constant level after treatment for 1 year or more with inhaled corticosteroids. Bronchial wall area and air trapping extent were compared in the recovered group (n = 18) and the persistent airway obstruction group (n = 14). Bronchial wall area and air trapping of the initial HRCT were similar between the two groups. On follow-up HRCT, air trapping was markedly decreased in the recovered group compared with that on initial HRCT (P = 0.017), whereas bronchial wall area did not change. In the persistent-airway-obstruction group, these two parameters did not change during follow-up. When follow-up HRCT was compared, air trapping was significantly greater in the persistent-airway-obstruction group than in the recovered group (P = 0.003). Difference post-bronchodilator FEV1 value between at initial and 2nd HRCT exam was correlated with difference air trapping value between at initial and 2nd HRCT exam(%) on the follow-up HRCT (P = 0.017). The presence of persistent airflow obstruction were significantly associated with the air trapping % difference between initial and 2nd time (RR = 1.70, P = 0.018). Persistence of AT could be a main contributing factor to chronic persistent airflow obstruction in asthma.

Lasp1 is down-regulated in NMDA receptor antagonist-treated mice and implicated in human schizophrenia susceptibility

Mice treated with MK-801, a non-competitive antagonist of the N-methyl-d-aspartic (NMDA) acid receptor, are important animal models for schizophrenia studies. In the present study, we compared protein expression levels in the hippocampus of mice treated with MK-801 (0.6 mg/kg) or saline once daily for 7 days. Changes in the proteome were detected by two-dimensional electrophoresis, and the six proteins exhibiting differential expression were identified by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry. Down-regulation of one of these proteins, Lasp1 (LIM and SH3 protein 1), in MK-801-treated mice was confirmed by western blotting and immunohistochemical analyses. Lasp1 is a multidomain protein that may recruit signaling molecules to the actin-based cytoskeleton and is known to concentrate in synaptic sites of hippocampal neurons. We next investigated whether polymorphisms in the human LASP1 gene were associated with schizophrenia in the Korean population. A single-nucleotide polymorphism in the LASP1 gene promoter region was associated with schizophrenia susceptibility. Our results suggest that LASP1 might be associated with NMDA receptor antagonism and schizophrenia susceptibility and, thus, might be involved in the pathophysiology of schizophrenia.