Adult-onset megacolon with focal hypoganglionosis: A detailed phenotyping and prospective cohort study

BACKGROUND

In this prospective cohort study, we evaluated features of "adult-onset megacolon with focal hypoganglionosis."

METHODS

We assessed the radiologic, endoscopic, and histopathologic phenotyping and treatment outcomes of 29 patients between 2017 and 2020. Data from community controls, consisting of 19,948 adults undergoing health screenings, were analyzed to identify risk factors. Experts reviewed clinical features and pathological specimens according to the London Classification for gastrointestinal neuromuscular pathology.

KEY RESULTS

The median age of the patients with adult-onset megacolon with focal hypoganglionosis at symptom onset was 59 years (range, 32.0-74.9 years), with mean symptom onset only 1 year before diagnosis. All patients had focal stenotic regions with proximal bowel dilatation (mean diameter, 78.8 mm; 95% confidence interval [CI], 72-86). The comparison with community controls showed no obvious risk factors. Ten patients underwent surgery, and all exhibited significant hypoganglionosis: 5.4 myenteric ganglion cells/cm (interquartile range [IQR], 3.7-16.4) in the stenotic regions compared to 278 cells/cm (IQR, 190-338) in the proximal and 95 cells/cm (IQR, 45-213) in the distal colon. Hypoganglionosis was associated with CD3+ T cells along the myenteric plexus. Colectomy was associated with significant symptom improvement compared to medical treatment [change in the Global Bowel Satisfaction score, -5.4 points (surgery) vs. -0.3 points (medical treatment); p < 0.001].

CONCLUSIONS AND INFERENCES

Adult-onset megacolon with focal hypoganglionosis has distinct features characterized by hypoganglionosis due to inflammation. Bowel resection appears to benefit these patients.

Impact of de novo tachyarrhythmias in patients with prior acute coronary syndrome

Although the incidence of acute coronary syndrome (ACS) has increased over the decades, the overall prognosis has improved with newer stents, tailored medication, and better intervention techniques. Atrial fibrillation (AF) and ventricular arrhythmia at the time of ACS diagnosis are known indicators of a poor acute prognosis. However, there is a lack of data regarding the long-term arrhythmic impact of ventricular tachyarrhythmia (VA) on mortality in ACS patients. This study sought to elucidate the impact of tachyarrhythmia on mortality during long-term follow-up in patients with a history of ACS. This retrospective study was conducted in a single university hospital, and it evaluated the clinical outcomes, especially regarding cardiovascular mortality and readmission. The enrolled patients underwent percutaneous coronary intervention (PCI) for ACS between February 2004 and March 2018. Clinical information was attained by a thorough chart review. We retrospectively analyzed 560 ACS patients. We reviewed all electrocardiograms (ECGs) before and immediately after PCI, during hospitalization, and within 3 months of the index PCI. Three months after the index PCI procedure, any Holter monitoring or ECG was also reviewed for arrhythmia diagnosis. During follow-up, 91 patients were diagnosed with AF and 36 patients were diagnosed with VA. Overall mortality was related to the presence of anemia, low body mass index, low left ventricular ejection fraction after PCI, late-diagnosed AF, and any VA during follow-up. Readmission was higher in patients with chronic kidney disease and newly diagnosed AF during the follow-up. Diagnosis of late tachyarrhythmia during follow-up was associated with increased mortality in post-ACS patients.

A comparative study of laparoscopic near-total and total gastrectomy for patient nutritional status and quality of life using a propensity score matching analysis

BACKGROUND

Previous studies of LNTG had small sample sizes and short follow-up periods and did not evaluate quality of life after LNTG. We aimed to compare surgical, oncological, nutritional outcomes, and quality of life of patients after laparoscopic near-total and total gastrectomy (LNTG and LTG, respectively).

METHODS

We retrospectively collected and analyzed data of 167 and 294 patients who underwent LNTG and LTG, respectively, for treatment of upper or middle third gastric cancer between January 2008 and December 2018. After propensity score matching, the surgical, oncological, and nutritional outcomes of 324 patients were analyzed. Moreover, we measured quality of life after surgery using a postgastrectomy syndrome scale.

RESULTS

The operation time and the length of hospital stay was significantly shorter in the LNTG group than in the LTG group. In addition, patients with anastomotic complications were fewer in the LNTG group. No significant difference was found in the 5-year overall survival rate between the two groups. However, patients in the LNTG group had a significantly smaller body weight loss after 3 months postoperatively. Furthermore, patients in the LNTG group had significantly healthier albumin and cholesterol than those in the LTG group. The mean scores on the postgastrectomy symptom scale at 3, 6, and 12 months postoperatively were higher in the LNTG group than in the LTG group.

CONCLUSION

LNTG is a surgically safe and oncologically favorable method compared with LTG. Furthermore, patients who underwent LNTG had improved nutritional status and quality of life than those who underwent LTG.

Long-Term Outcomes After Percutaneous Coronary Intervention With Second-Generation Drug-Eluting Stents or Coronary Artery Bypass Grafting for Multivessel Coronary Disease

More evidence is required with respect to the comparative effectiveness of percutaneous coronary intervention (PCI) with second-generation drug-eluting stents (DESs) versus coronary artery bypass grafting (CABG) in contemporary clinical practice. This prospective observational registry-based study compared the outcomes of 6,647 patients with multivessel disease who underwent PCI with second-generation DES (n = 3,858) or CABG (n = 2,789) between January 2006 and June 2018 and for whom follow-up data were available for at least 2 to 13 years (median 4.8). The primary outcome was a composite of death, spontaneous myocardial infarction, or stroke. Baseline differences were adjusted using propensity scores and inverse probability weighting. In the overall cohort, there were no significant between-group differences in the adjusted risks for the primary composite outcome (hazard ratio [HR] for PCI vs CABG 1.03, 95% confidence interval [CI] 0.86 to 1.25, p = 0.73) and all-cause mortality (HR 0.95, 95% CI 0.76 to 1.20, p = 0.68). This relative treatment effect on the primary outcome was similar in patients with diabetes (HR 1.15, 95% CI 0.91 to 1.46, p = 0.25) and without diabetes (HR 0.95, 95% CI 0.73 to 1.22, p = 0.67) (p for interaction = 0.24). The adjusted risk of the primary outcome was significantly greater after PCI than after CABG in patients with left main involvement (HR 1.39, 95% CI 1.01 to 1.90, p = 0.044), but not in those without left main involvement (HR 0.94, 95% CI 0.76 to 1.16, p = 0.56) (p = 0.03 for interaction). In this prospective real-world long-term registry, we observed that the risk for the primary composite of death, spontaneous myocardial infarction, or stroke was similar between PCI with contemporary DES and CABG.

Ten-year outcomes of early generation sirolimus- versus paclitaxel-eluting stents in patients with left main coronary artery disease

To compare 10-year outcomes after implantation of sirolimus-eluting stents (SES) versus paclitaxel-eluting stents (PES) for left main coronary artery (LMCA) stenosis. Very long-term outcome data of patients with LMCA disease treated with drug-eluting stents (DES) have not been well described. In 10-year extended follow-up of the MAINCOMPARE registry, we evaluated 778 patients with unprotected LMCA stenosis who were treated with SES (n = 607) or PES (n = 171) between January 2000 and June 2006. The primary composite outcome (a composite of death, myocardial infarction [MI] or target-vessel revascularization [TVR]) was compared with an inverse-probability-of-treatment-weighting (IPTW) adjustment. Clinical events have linearly accumulated over 10 years. At 10 years, there were no significant differences between SES and PES in the observed rates of the primary composite outcome (42.0% vs. 47.4%; hazard ratio [HR] 0.85; 95% confidence interval [CI] 0.66-1.10), and definite stent thrombosis (ST) (1.9% vs. 1.8%; HR 1.02, 95% CI 0.28-3.64). In the IPTW-adjusted analyses, there were no significant differences between SES and PES in the risks for the primary composite outcome (HR 0.89, 95% CI 0.65-1.14) or definite ST (adjusted HR 1.05, 95% CI 0.29-3.90). In patients who underwent DES implantation, high overall adverse clinical event rates (with a linearly increasing event rate over time) were observed during extended follow-up. At 10 years, there were no measurable differences in outcomes between patients treated with SES vs. PES for LMCA disease. The incidence of stent thrombosis was quite low and comparable between the groups.

Initial experience of endoscopic ultrasound-guided antegrade covered stent placement with long duodenal extension for malignant distal biliary obstruction (with video)

Background/Purpose

This study aimed to evaluate the feasibility of endoscopic ultrasound (EUS)‐guided antegrade covered stent placement with long duodenal extension (EASL) for malignant distal biliary obstruction (MDBO) with duodenal obstruction (DO) or surgically altered anatomy (SAA) after failed endoscopic retrograde cholangiopancreatography (ERCP).

Methods

Outcomes were technical and clinical success, reintervention rate, adverse events, stent patency, and overall survival. Inverse probability of treatment weighting (IPTW) and competing‐risk analysis were performed to compare with conventional EUS‐BD.

Results

Twenty‐five patients (DO, n = 18; SAA, n = 7) were included. The technical and clinical success rates were 96% and 84%, respectively. Reintervention occurred in two patients (8.3%). Adverse events occurred in six patients (24%; two cholangitis, 16%; four mild postprocedural pancreatitis [24% (n = 4/17) in patients with non‐pancreatic cancers]). The median patency was 9.4 months, and the overall survival was 2.73 months. After IPTW adjustment, the median patency in the EASL (n = 25) and conventional EUS‐BD (n = 29) were 10.1 and 6.5 months, respectively (P = .018).

Conclusions

EASL has acceptable clinical outcomes with a low reintervention rate but higher rate of postprocedural pancreatitis in patients with non‐pancreatic cancers. Randomized trials comparing EASL and conventional EUS‐BD for MDBO with pancreatic cancers and DO/SAA after failed ERCP are needed to validate our findings.

Comparison of metabolic changes after neoadjuvant endocrine and chemotherapy in ER-positive, HER2-negative breast cancer

Survival of breast cancer patients has improved, and treatment-related changes regarding metabolic profile deterioration after neoadjuvant systemic treatment (NST) become important issues in cancer survivors. We sought to compare metabolic profile changes and the neutrophil-to-lymphocyte ratio (NLR) between patients undergoing neoadjuvant chemotherapy (NCT) and neoadjuvant endocrine therapy (NET) 3 years after the treatment. In a prospective, randomized, phase III trial which compared 24 weeks of NCT with adriamycin and cyclophosphamide followed by docetaxel and NET with goserelin and tamoxifen (NEST), 123 patients in the Asan Medical Center were retrospectively reviewed to evaluate metabolic changes, such as body mass index (BMI), blood pressure (BP), total cholesterol (TC), fasting glucose, and the NLR. The mean age of patients was 42 years. The changes in BMI, serum glucose, and TC during NST and after 3 years were significantly different between NCT and NET. The proportion of overweight + obese group and the mean BMI were significantly increased during NCT (26.6% to 37.5%, 22.84 kg/m2 to 23.87 kg/m2, p < 0.05), and these attributes found to have normalized at the 3-year follow-up. In the NET group, BMI changes were not observed (p > 0.05, all). There were no differences in changes over time among in the Hypertension group during NCT and NET (p = 0.96). The mean value of serum TC and fasting glucose significantly increased (< 0.05, both) during NCT and decreased 3 years after NCT (p < 0.05); however, no significant changes were observed in the NET group. The NLR was increased from 1.83 to 3.18 after NCT (p < 0.05) and decreased from 1.98 to 1.43 (p < 0.05) after NET. Compared with minimal metabolic effect of NET, NCT worsens metabolic profiles, which were recovered over 3 years. The NLR was increased after NCT but decreased after NET.

Distinctive patterns of pulmonary function change according to baseline lung volume and diffusing capacity

SETTING: Multicentre retrospective study in South Korea.OBJECTIVE: To longitudinally evaluate changes in lung volume and diffusing capacity for carbon monoxide (DLCO) with forced expiratory volume in 1 sec (FEV₁).DESIGN: A total of 155 patients with chronic obstructive pulmonary disease (COPD), whose pulmonary function parameters were measured annually for 5 years, were selected from a prospective cohort in South Korea. A random coefficients model was used to estimate mean annual FEV₁, lung volume parameter and DLCO change rates.RESULTS: Patients were classified into four groups based on baseline DLCO and residual volume/total lung capacity (RV/TLC) measurements. The annual FEV₁ decline rate was greater in patients with low DLCO than in those with normal DLCO, with the greatest decline occurring in patients with low DLCO and normal RV/TLC. RV and RV/TLC declined in patients with high RV/TLC, whereas these increased in patients with normal RV/TLC. DLCO decreased longitudinally in all four groups, with the greatest decline occurring in patients with normal DLCO and normal RV/TLC.CONCLUSIONS: Different subgroups of patients with COPD exhibited distinctive pulmonary function change patterns. Baseline DLCO and RV/TLC may be used as physiological markers to predict long-term changes in pulmonary function.

Utility of Magnetic Resonance Imaging for Differentiating Necrotizing Fasciitis from Severe Cellulitis: A Magnetic Resonance Indicator for Necrotizing Fasciitis (MRINEC) Algorithm

We developed a new magnetic resonance indicator for necrotizing fasciitis (MRINEC) algorithm for differentiating necrotizing fasciitis (NF) from severe cellulitis (SC). All adults with suspected NF between 2010 and 2018 in a tertiary hospital in South Korea were enrolled. Sixty-one patients were diagnosed with NF and 28 with SC. Among them, 34 with NF and 15 with SC underwent magnetic resonance imaging (MRI). The MRINEC algorithm, a two-step decision tree including T2 hyperintensity of intermuscular deep fascia and diffuse T2 hyperintensity of deep peripheral fascia, diagnosed NF with 94% sensitivity (95% confidence interval (CI), 80–99%) and 60% specificity (95% CI, 32–84%). The algorithm accurately diagnosed all 15 NF patients with a high (≥8) laboratory risk indicator for necrotizing fasciitis (LRINEC) score. Among the five patients with an intermediate (6–7) LRINEC score, sensitivity and specificity were 100% (95% CI, 78–100%) and 0% (95% CI, 0–84%), respectively. Finally, among the 29 patients with a low (≤5) LRINEC score, the algorithm had a sensitivity and specificity of 88% (95% CI, 62–98%) and 69% (95% CI, 39–91%), respectively. The MRINEC algorithm may be a useful adjuvant method for diagnosing NF, especially when NF is suspected in patients with a low LRINEC score.

Efficacy and Safety of Cystatin C-Guided Renal Dose Adjustment of Cefepime Treatment in Hospitalized Patients with Pneumonia

Cystatin C (CysC) may estimate renal function more accurately than serum creatinine (SCr). The clinical impact of renal dose adjustment of cefepime according to CysC rather than SCr has remained uncertain. We investigated the efficacy and safety of CysC-guided cefepime dosing compared with SCr-guided dosing in hospitalized patients with pneumonia. All adults hospitalized with pneumonia between July 2016 and December 2018 who used cefepime for at least 3 days were enrolled. Mortality, acute kidney injury (AKI), cefepime-induced encephalopathy (CIE), and Clostridium difficile infection were compared between the CysC-guided and SCr-guided groups. One hundred and ninety patients were divided into two groups: 129 and 61 received cefepime based on CysC and SCr, respectively. In-hospital mortality did not significantly differ between the groups (12% versus 31%; hazard ratio (HR) 0.74; 95% confidence interval (CI), 0.31-1.77; p = 0.50). CysC-guided cefepime dosing decreased the risk of AKI (13% versus 61%; HR 0.18; 95% CI, 0.07-0.44; p < 0.001) and CIE (2% versus 11%; HR 0.11; 95% CI, 0.03-0.47; p = 0.003) compared with SCr-guided dosing. There was no significant difference in the risk of Clostridium difficile infection. CysC-guided dosing of cefepime was associated with decreased risk of the cefepime-associated morbidities including AKI and CIE without increasing mortality among the hospitalized patients with pneumonia.

Prognostic Value of Radiologic Extranodal Extension in Human Papillomavirus-Related Oropharyngeal Squamous Cell Carcinoma

Objective

To determine whether radiologic extranodal extension (ENE) appearing on pretreatment CT and MRI could predict the prognosis in patients with human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC).

Materials and Methods

The study population was obtained from a historical cohort diagnosed with HPV-related OPSCC. A total of 134 OPSCC patients who had a metastatic lymph node on pretreatment CT or MRI were included, and radiologic ENE was evaluated by two experienced head and neck radiologists. Kaplan-Meier and multivariate Cox regression analyses were performed to evaluate the impact of radiologic ENE on progression-free survival (PFS). The diagnostic performance of CT and MRI for the diagnosis of ENE was also evaluated in patients who underwent neck dissection.

Results

Seventy patients (52.2%) showed radiologic ENE-positive findings. Although patients showing radiologic ENE had a worse 3-year PFS (83.7% vs. 95.3%, p = 0.023), the association between radiologic ENE and PFS was not statistically significant on multivariate analysis (p = 0.141; hazard ratio, 2.68; 95% confidence interval, 0.72–9.97). CT or MRI had a sensitivity of 62%, specificity of 77.8%, and accuracy of 71.9% for predicting pathologic ENE.

Conclusion

Radiologic ENE on CT or MRI did not predict poor PFS in patients with HPV-related OPSCC, although there was a trend towards worse PFS. Further studies are warranted to determine whether radiologic ENE is a useful imaging biomarker to risk-stratify patients with HPV-related OPSCC.

Impact of beta blockers on survival outcomes in ovarian cancer: a nationwide population-based cohort study

Objective

The impact of beta blockers (BBs) on survival outcomes in ovarian cancer was investigated.

Methods

By using Korean National Health Insurance Service Data, Cox proportional hazards regression was performed to analyze hazard ratios (HRs) with 95% confidence intervals (CIs) adjusting for confounding factors.

Results

Among 866 eligible patients, 206 (23.8%) were BB users and 660 (76.2%) were non-users. Among the 206 BB users, 151 (73.3%) were non-selective beta blocker (NSBB) users and 105 (51.0%) were selective beta blocker (SBB) users. BB use in patients aged ≥60 years, longer duration use (≥1 year), in patients with Charlson Comorbidity Index (CCI) ≥3, and in cardiovascular disease including hypertension was associated with better survival outcome. These findings were observed in both NSBB and SBB. When duration of medication was analyzed based on number of days, NSBB (≥180 days) was associated with improved overall survival (OS) with a relatively shorter period of use compared to SBB (≥720 days). In multivariate Cox proportional hazards model, longer duration of BB medication (≥1 year) was an independent favorable prognostic factor for both OS and disease-specific survival in ovarian cancer patients.

Conclusion

In our nationwide population-based cohort study, BB use was associated with better survival outcomes in ovarian cancer in cases of long term duration of use, in older patients, and in cardiovascular and/or other underlying disease (CCI ≥3).

A Scoring System for Prediction of Cervical Lymph Node Metastasis in Patients with Head and Neck Squamous Cell Carcinoma

BACKGROUND AND PURPOSE

An accurate and comprehensive assessment of lymph node metastasis in patients with head and neck squamous cell cancer is crucial in daily practice. This study constructed a predictive model with a risk scoring system based on CT characteristics of lymph nodes and tumors for patients with head and neck squamous cell carcinoma to stratify the risk of lymph node metastasis.

MATERIALS AND METHODS

Data included 476 cervical lymph nodes from 191 patients with head and neck squamous cell carcinoma from a historical cohort. We analyzed preoperative CT images of lymph nodes, including diameter, ratio of long-to-short axis diameter, necrosis, conglomeration, infiltration to adjacent soft tissue, laterality and T-stage of the primary tumor. The reference standard comprised pathologic results. Multivariable logistic regression analysis was performed to develop the risk scoring system. Internal validation was performed with 1000-iteration bootstrapping.

RESULTS

Shortest axial diameter, ratio of long-to-short axis diameter, necrosis, and T-stage were used to develop a 9-point risk scoring system. The risk of malignancy ranged from 7.3% to 99.8%, which was positively associated with increased scores. Areas under the curve of the risk scoring systems were 0.886 (95% CI, 0.881-0.920) and 0.879 (95% CI, 0.845-0.914) in internal validation. The Hosmer-Lemeshow goodness-of-fit test indicated that the risk scoring system was well-calibrated (P = .160).

CONCLUSIONS

We developed a comprehensive and simple risk scoring system using CT characteristics in patients with head and neck squamous cell carcinoma to stratify the risk of lymph node metastasis. It could facilitate decision-making in daily practice.

The effect of eradication of Helicobacter pylori on gastric cancer prevention in healthy asymptomatic populations

BACKGROUND

Although many epidemiologic studies have evaluated the effect of Helicobacter pylori eradication on gastric cancer, the effect is still uncertain in general populations. We evaluated whether H. pylori eradication would affect the incidence of gastric cancer in healthy asymptomatic populations.

MATERIALS AND METHODS

We performed a retrospective cohort study in 38 984 asymptomatic individuals, who underwent health screening examinations more than twice between 2005 and 2016. We investigated the incidence of gastric cancer among 3 groups: those without H. pylori infection (Hp-negative group), those with H. pylori eradication (eradication group), and those without H. pylori eradication (non-eradication group).

RESULTS

The cumulative incidence of gastric cancer was 54.5 cases per 100 000 person-years during a median of 6.4 years. In a multivariate analysis using the Cox proportional hazard model, the cumulative incidence of gastric cancer in the non-eradication group was significantly higher than those in the Hp-negative (hazard ratio [HR] 4.12, P < .001) and eradication groups (HR 2.73, P = .001). However, the cumulative incidence of gastric cancer was not significantly different between the eradication and Hp-negative groups. Other risk factors for gastric cancer occurrence were age, smoking, family history of gastric cancer, and gastric atrophy. The standardized incidence ratios of the age groups above 40 and below 70 in the eradication group were all significantly decreased.

CONCLUSIONS

Helicobacter pylori eradication reduced the cumulative incidence of gastric cancer in healthy asymptomatic population, and the effect of H. pylori eradication on the prevention of gastric cancer was observed in all ages.

The Association of Fever with Total Mechanical Ventilation Time in Critically Ill Patients

This research aims to investigate the impact of fever on total mechanical ventilation time (TVT) in critically ill patients. Subgroup analysis was conducted using a previous prospective, multicenter observational study. We included mechanically ventilated patients for more than 24 hours from 10 Korean and 15 Japanese intensive care units (ICU), and recorded maximal body temperature under the support of mechanical ventilation (MAX(MV)). To assess the independent association of MAX(MV) with TVT, we used propensity-matched analysis in a total of 769 survived patients with medical or surgical admission, separately. Together with multiple linear regression analysis to evaluate the association between the severity of fever and TVT, the effect of MAX(MV) on ventilator-free days was also observed by quantile regression analysis in all subjects including non-survivors. After propensity score matching, a MAX(MV) ≥ 37.5°C was significantly associated with longer mean TVT by 5.4 days in medical admission, and by 1.2 days in surgical admission, compared to those with MAX(MV) of 36.5°C to 37.4°C. In multivariate linear regression analysis, patients with three categories of fever (MAX(MV) of 37.5°C to 38.4°C, 38.5°C to 39.4°C, and ≥ 39.5°C) sustained a significantly longer duration of TVT than those with normal range of MAX(MV) in both categories of ICU admission. A significant association between MAX(MV) and mechanical ventilator-free days was also observed in all enrolled subjects. Fever may be a detrimental factor to prolong TVT in mechanically ventilated patients. These findings suggest that fever in mechanically ventilated patients might be associated with worse mechanical ventilation outcome.

Decrease of serum total ghrelin in extensive atrophic gastritis: comparison with pepsinogens in histological reference

OBJECTIVE

Ghrelin is mainly secreted by the gastric oxyntic mucosa and its production is impaired in chronic atrophic gastritis. This study aimed at evaluating how serum total ghrelin correlates with the extent of atrophy, and to compare its performance as a serologic marker with that of pepsinogen (PG).

MATERIAL AND METHODS

Data were collected from 154 patients with atrophic gastritis. The histological extent of atrophy was assessed by three paired biopsies from the antrum, corpus lesser curvature (CLC), and corpus greater curvature (CGC). Fasting serum concentrations of total ghrelin, pepsinogen I and II were measured. Regression analysis was performed to evaluate the factors associated with serum total ghrelin. The serologic performance was compared with that of pepsinogen using receiver-operating characteristic (ROC) curves.

RESULTS

The Helicobacter pylori infection rate was 85%, and extensive atrophic gastritis involving CGC was found in 24%. Serum total ghrelin was significantly decreased in patients with extensive CGC atrophy (median: 170.4 pg/mL, vs 201.1 pg/mL in patients without atrophy; p < 0.001), and its levels correlated with those of pepsinogen I and I/II ratio. The decrease of serum total ghrelin was independent of age, gender, body mass index (BMI), and H. pylori infection status. The sensitivity and specificity of serum total ghrelin in predicting extensive atrophy were 57% and 79%, respectively. The discriminatory ability was similar to that of pepsinogen I/II ratio (p = 0.612), and lower than that of pepsinogen I (p = 0.040).

CONCLUSIONS

Serum total ghrelin is decreased during extensive atrophy involving CGC. The serologic performance is lower than that of pepsinogen I.

Comparison of Strain in GaN-Based Blue Light-Emitting Diode Grown on Silicon(111) and Sapphire Substrates

We compare the strain states and device performances of GaN-based blue light-emitting diodes (LEDs) grown on Si(111) and sapphire substrates. The strain characteristics are investigated using micro-Raman spectroscopy and high-resolution transmission electron microscopy. These analyses reveal that GaN layer grown on Si has a residual tensile strain in contrast to a compressive strain for GaN on sapphire, and quantum wells (QWs) on GaN/Si experience reduced lattice mismatch than those of GaN/sapphire. When external quantum efficiencies of LED on sapphire and Si substrates are compared, the LED on Si shows better efficiency droop characteristics and this is attributed to a decrease in piezo-electric field strength in InGaN/GaN layers owing to reduced lattice mismatch.

An adequate level of training for technically competent colonoscopic polypectomy

GOALS

The purpose of this study is to investigate the learning curve for colonoscopic polypectomy (CP) by trainee endoscopists.

BACKGROUND

The amount of training required to achieve technical competence for CP is uncertain.

STUDY

The CP times and en bloc resection rates of three experienced colonoscopists were obtained from 240 procedures. These data were compared to those of three gastroenterology trainees who performed 750 CP procedures. A trainee procedure was deemed to be a success if en bloc resection was obtained and the CP time was within twice the median CP time of the experienced colonoscopists. Trainees were deemed to be technically competent when they achieved a CP success rate of greater than or equal to 80%.

RESULTS

The median CP times and en bloc resection rates for the experienced colonoscopists and trainees were 79 s (range, 20-301 s) and 99.6% (239/240), and 118 s (range, 36-1051 s) and 95.6% (717/750), respectively. The trainee success rate of CP was 72% (540/750). The success rate of the procedure was associated with increased trainee experience (p = 0.003) and reached 80% after 250 procedures. The CP time significantly decreased (p < 0.001) and en bloc resection rate significantly increased (p = 0.011) as trainee experience accumulated. The level of experience was an independent predictor for successful CP.

CONCLUSIONS

The achievement of technical competence with CP was associated with an accumulation of approximately 250 procedures. These findings suggest that dedicated education and training programs for CP are warranted.

Reconstruction algorithm for nasal basal cell carcinoma with skin involvement only: analysis of 221 cases repaired by minor surgery

BACKGROUND

Basal cell carcinoma (BCC) often occurs on the nose. Reconstruction of the nose should yield excellent aesthetic and functional outcomes.

AIM

We propose a technical algorithm for the reconstruction of surgical defects, based on our analysis of 221 cases of nasal BCC with skin involvement only, which could be repaired by minor surgery.

METHODS

The aesthetic and functional outcomes for various reconstruction techniques were analysed according to defect location and size. A reconstruction algorithm was proposed with the aim of obtaining the best surgical results.

RESULTS

Defect location and size were key considerations. Primary closure was the first option for small defects (< 10 mm), with scores of 3.4 for objective aesthetic outcome (OAO), 3.2 for subjective aesthetic outcome (SAO) and 3.3 for subjective functional outcome (SFO). The first option for medium defects (1-20 mm) was the island pedicle flap, with scores of 3.5 for OAO, 3.2 for SAO and 3.7 for SFO. The first option for large defects (> 20 mm) was the transposition flap for the upper nose (scores of 2.0 for OAO and SAO and 3.0 for SFO) and the interpolation flap for the lower nose (2.8 for OAO and 2.9 for SAO and SFO).

CONCLUSIONS

We have proposed an algorithm to select the optimal technique for repairing nasal BCC surgical defects according to their size and location.

The assessment of the stability in mandibular setback surgery related to spatial factors under rotational control of the proximal segment

OBJECTIVE

To evaluate the surgical relapse of mandibular setback, related to the magnitude of setback and LeFort I osteotomy under rotational control of the proximal segment.

STUDY DESIGN

Data from 78 patients who had undergone sagittal split ramus osteotomy for mandibular prognathism were reviewed. The stability of the proximal segment was retrospectively confirmed. Serial cephalograms were used to assess relapse over 1 year. The association between relapse and LeFort I osteotomy as well as the magnitude of setback was assessed.

RESULTS

Minimal counterclockwise rotation was noted postoperatively, but the proximal segment remained stable for 1 year. Notable forward relapse was shown in the setback of more than 7 mm (P < .01) with resumption of function after 6 weeks, but it was not related with LeFort I osteotomy.

CONCLUSIONS

Relapse was related to the amount of setback and occurred on resumption of function despite rotational control of the proximal segment.

Adjuvant radiotherapy for stage III/IV urothelial carcinoma of the upper tract

AIM

In order to define the role of adjuvant radiotherapy (RT), the clinical outcomes of patients with stage III/IV urothelial carcinoma of the upper urinary tract (UTUC) were reviewed.

PATIENTS AND METHODS

Clinical data from a total of 127 patients who underwent radical nephroureterectomy with bladder cuff were analyzed. While 36 patients underwent adjuvant RT following surgery, 91 were treated with surgery-alone. Differences in risk-adjusted treatment outcomes between the two groups were assessed using a multivariable Cox proportional-hazards model and inverse probability of treatment weighting with propensity score for balancing covariates including use of chemotherapy between the two groups was estimated.

RESULTS

With a median follow-up of 38.3 months, 3-year actuarial locoregional recurrence-free survival rates were 89% vs. 61% in the RT vs. non-RT groups, respectively (p=0.01). Three-year bladder recurrence-free survival rates were 73% and 52% in favor of the RT group (p=0.02). After adjustment for differences in covariates, the risks of locoregional, bladder, and disease recurrence were found significantly lower in the RT group.

CONCLUSION

Adjuvant RT may be beneficial in terms of locoregional and bladder control in patients with stage III/IV UTUC. Further prospective studied are needed to verify these findings.

Longitudinal lung volume changes in patients with chronic obstructive pulmonary disease

BACKGROUND

The progression of lung hyperinflation in patients with chronic obstructive pulmonary disease (COPD) has not been studied in a long-term prospective cohort. We explored the longitudinal changes in lung volume compartments with the aim of identifying predictors of a rapid decline of the inspiratory capacity to total lung capacity ratio (IC/TLC).

METHODS

The study population comprised 324 patients with COPD who were recruited prospectively. Annual rates of changes in pulmonary function, including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), total lung capacity (TLC), functional residual capacity (FRC), residual volume (RV), vital capacity (VC), IC, and IC/TLC, were estimated using the random coefficient models.

RESULTS

The mean annual rates of changes in pre- and post-bronchodilator FEV1 were -23.0 mL/year (p < 0.001) and -26.5 mL/year (p = 0.004). The mean annual rates of changes in VC, IC, TLC, and IC/TLC were -33.7 mL/year (p = 0.007), -53.9 mL/year (p < 0.001), -43.7 mL/year (p = 0.012), and -0.65%/year (p = 0.001), respectively. RV, FRC, and RV/TLC did not change significantly during the study period. Multivariate logistic regression analysis showed that a high modified Medical Research Council (MMRC) dyspnea scale score, a high Charlson comorbidity index value, and low post-bronchodilator FEV1 were associated with rapid decline in IC/TLC.

CONCLUSION

MMRC dyspnea scale, post-bronchodilator FEV1, and the Charlson comorbidity index at baseline were independent predictors of a rapid decline in IC/TLC.

Use of mean spot urine sodium concentrations to estimate daily sodium intake in patients with chronic kidney disease

OBJECTIVE

Sodium intake is an important issue for patients with chronic kidney disease (CKD). The two most widely used methods to measure sodium are 24-h urinary sodium excretion (24HUNa), which can be difficult to perform routinely, and sodium intake by dietary recall, which can be inaccurate. This study evaluated use of the mean value of three spot urinary sodium (UNa) concentrations to estimate daily sodium intake in patients with CKD.

METHODS

This cross-sectional study enrolled 305 patients with CKD, none of whom were on dialysis, who visited the nephrology clinic at the Asan Medical Center (Seoul, Korea). We performed three spot UNa tests, three calculations of the UNa/creatinine (UCr) ratio, one measurement of 24HUNa, and one measurement of sodium intake by dietary recall.

RESULTS

The 24HUNa and mean spot UNa values were significantly lower in patients with more advanced CKD (P = 0.006 and P < 0.001, respectively). One-time spot UNa was significantly higher in the evening than in the morning for patients with stage III, IV, or V CKD. Total sodium intake, but not sodium nutrient density (milligrams of sodium per 1000 kcal), was significantly different for patients with different stages of CKD (P = 0.001). The correlation coefficient between 24HUNa and mean spot UNa was 0.477 (95% confidence interval [CI] 0.384-0.562, P < 0.001), slightly higher than that between 24HUNa excretion and mean spot UNa/UCr (r = 0.313, 95% CI 0.207-0.465, P < 0.001). There was a linear relation between spot UNa and 24HUNa: mean spot UNa = 0.27 × 24HUNa + 60. Therefore, a 24HUNa excretion of 87 mEq (sodium intake 2 g/d) corresponded to a mean spot UNa level of 83 mEq/L. The correlation coefficient between sodium intake and mean spot UNa was 0.435 (95% CI 0.336-0.524, P < 0.001), significantly higher than that between sodium intake and mean spot UNa/UCr (r = 0.197, 95% CI 0.091-0.301, P = 0.001). Mean spot UNa tended to be better correlated with 24HUNa than with sodium intake.

CONCLUSION

Mean spot UNa is a simple and effective method that can be used to monitor sodium intake in patients with CKD. A daily intake of 2 g of sodium corresponds to a mean spot UNa level of approximately 83 mEq/L in patients with CKD.

EMR versus gastrectomy for intramucosal gastric cancer: comparison of long-term outcomes

BACKGROUND

Limited data exist regarding the long-term outcomes of EMR compared with gastrectomy.

OBJECTIVE

To compare the long-term outcomes after EMR and surgery.

DESIGN

Retrospective analysis with propensity-score matching.

SETTING

Tertiary care center.

PATIENTS

This study involved 215 patients with intramucosal gastric cancer completely removed by EMR and 843 patients who underwent curative surgical resection between January 1997 and August 2002. Propensity-score matching yielded 551 matched patients.

INTERVENTIONS

EMR versus surgery.

MAIN OUTCOME MEASUREMENTS

Death and recurrence.

RESULTS

In the matched cohort, there were no significant between-group differences in the risk of death (hazard ratio [HR] for the EMR group 1.39; 95% CI, 0.87-2.23) or recurrence (HR 1.18; 95% CI, 0.22-6.35). Although patients who underwent EMR had higher risk of metachronous gastric cancers (HR 6.72; 95% CI, 2.00-22.58), all recurrent or metachronous gastric cancers after EMR were successfully re-treated without affecting overall survival. Although complication rates were similar (odds ratio 0.84; 95% CI, 0.41-1.70), there were no mortalities in the EMR group compared with 2 in the surgery group. The EMR group had a significantly shorter hospital stay (median 8 days, interquartile range [IQR] 6-11 days vs 15 days, IQR 12-19 days; P<.001) and lower cost of care ($2049, IQR $1586-2425 vs $4042, IQR $3458-4959; P<.001).

LIMITATIONS

Retrospective, nonrandomized study.

CONCLUSIONS

EMR was comparable to surgery in terms of risk of death and recurrence. Because of its lower medical costs and shorter duration of hospital stay, EMR has advantages over surgery.

The objective evaluation of the severity of psoriatic scales with desquamation collecting tapes and image analysis

BACKGROUND

Assessment of psoriatic scales is important to determine the severity of psoriasis. However, there are very limited numbers of objective, quantitative and observer-independent tools for measuring the severity of psoriasis.

OBJECTIVE

To determine whether the bioengineering parameters of the psoriatic scale can be used to assess the severity of psoriasis instead of the psoriatic severity index of scales (PSIs) score.

METHODS

Thirty-four patients with psoriasis were included. A representative lesion from each patient was selected and bioengineering parameters were measured using the Corneofix(®). Simultaneously, the severity of the scales was assessed by the PSIs score using clinical photographs of the lesions. In addition, skin color and elasticity parameters were also measured using the Colorimeter(®), the Mexameter(®) and the Cutometer(®).

RESULTS

Statistical differences in the scale parameters were observed between the PSIs 2 and 3 scores. Among the scale parameters, the percent area and area in μm(2) were negatively correlated with the PSIs score. In addition, the Colorimeter(®) a, b parameters and the Cutometer(®) R9 parameters were significantly correlated with the PSIs score.

CONCLUSIONS

The results of this study showed that the severity of psoriatic scales could be measured objectively using the Corneofix(®).

Smoking, longer disease duration and absence of rhinosinusitis are related to fixed airway obstruction in Koreans with severe asthma: findings from the COREA study

Background

The clinical manifestations of severe asthma are heterogeneous. Some individuals with severe asthma develop irreversible fixed airway obstruction, which is associated with poor outcomes. We therefore investigated the factors associated with fixed airway obstruction in Korean patients with severe asthma.

Methods

Severe asthma patients from a Korean adult asthma cohort were divided into two groups according to the results of serial pulmonary function tests. One group had fixed airway obstruction (FAO) [forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) ratio < 0.7, n = 119] and the other had reversible airway obstruction (RAO) [FEV1/FVC ratio ≥ 0.7, n = 116]. Clinical and demographic parameters were compared between the two groups.

Results

Multivariate analysis showed that longer duration of disease, greater amount of cigarette smoking and absence of rhinosinusitis were significantly related to the development of FAO in severe asthmatics. Other parameters, including atopic status, pattern of airway inflammatory cells in induced sputum, and frequency of asthma exacerbations did not differ between the FAO and RAO groups.

Conclusion

Severe asthma patients with longer disease duration and the absence of rhinosinusitis are more likely to develop FAO. This study also demonstrates the importance of quitting smoking in order to prevent irreversible airway obstruction. Further investigation is required to determine the mechanism by which these factors can modify the disease course in Korean patients with severe asthma.

Remifentanil protects myocardium through activation of anti-apoptotic pathways of survival in ischemia-reperfused rat heart

Remifentanil is a commonly used opioid in anesthesia with cardioprotective effect in ischemia-reperfused (I/R) heart. We evaluated the influence of remifentanil on myocardial infarct size and expressions of proteins involved in apoptosis in I/R rat heart following various time protocols of remifentanil administration. Artificially ventilated anesthetized Sprague-Dawley rats were subjected to a 30 min of left anterior descending coronary artery occlusion followed by 2 h of reperfusion. Rats were randomly assigned to one of five groups; Sham, I/R only, remifentanil preconditioning, postconditioning and continuous infusion group. Myocardial infarct size, the phosphorylation of ERK1/2, Bcl2, Bax and cytochrome c and the expression of genes influencing Ca2+ homeostasis were assessed. In remifentanil-administered rat hearts, regardless of the timing and duration of administration, infarct size was consistently reduced compared to I/R only rats. Remifentanil improved expression of ERK1/2 and anti-apoptotic protein Bcl2, and expression of sarcoplasmic reticulum genes which were significantly reduced in the I/R rats only. Remifentanil reduced expression of pro-apoptotic protein, Bax and cytochrome c. These suggested that remifentanil produced cardioprotective effect by preserving the expression of proteins involved in anti-apoptotic pathways, and the expression of sarcoplasmic reticulum genes in I/R rat heart, regardless of the timing of administration.

Reactive oxygen species in rats with chronic post-ischemia pain

BACKGROUND

An emerging theme in the study of the pathophysiology of persistent pain is the role of reactive oxygen species (ROS). In the present study, we examined the hypothesis that the exogenous supply of antioxidant drugs during peri-reperfusion would attenuate pain induced by ischemia/reperfusion (IR) injury. We investigated the analgesic effects of three antioxidants administered during peri-reperfusion using an animal model of complex regional pain syndrome-type I consisting of chronic post-ischemia pain (CPIP) of the hind paw.

METHODS

Application of a tight-fitting tourniquet for a period of 3 h produced CPIP in male Sprague-Dawley rats. Low-dose allopurinol (4 mg/kg), high-dose allopurinol (40 mg/kg), superoxide dismutase (SOD, 4000 U/kg), N-nitro-L-arginine methyl ester (L-NAME, 10 mg/kg), or SOD (4000 U/kg)+L-NAME (10 mg/kg) was administered intraperitoneally just after tourniquet application and at 1 and 2 days after reperfusion for 3 days. The effects of antioxidants in rats were investigated using mechanical and cold stimuli. Each group consisted of seven rats.

RESULTS

Allopurinol caused significant alleviation in mechanical and cold allodynia for a period of 4 weeks in rats with CPIP. Both SOD and L-NAME, which were used to investigate the roles of superoxide (O2(-)) and nitric oxide (NO) in pain, also attenuated neuropathic-like pain symptoms in rats for 4 weeks.

CONCLUSIONS

Our findings suggest that O2(-) and NO mediate IR injury-induced chronic pain, and that ROS scavengers administered during the peri-reperfusion period have long-term analgesic effects.

Caspase-3 activation as a key factor for HBx-transformed cell death

OBJECTIVES

Nuclear factor-kappa B (NF-kappaB) activation has been associated with the tumorigenic growth of hepatitis B virus X protein (HBx)-transformed cells. This study was aimed to find a key target for treatment of HBx-mediated cancers.

MATERIALS AND METHODS

NF-kappaB activation, endoplasmic reticulum-stress (ER-stress), caspase-3 activation, and cell proliferation were evaluated after Chang/HBx cells permanently expressing HBx viral protein were treated with inhibitors of NF-kappaB, proteasome and DNA topoisomerase.

RESULTS

Inhibition of NF-kappaB transcriptional activity by transient transfection with mutant plasmids encoding Akt1 and glycogen synthase kinase-3beta (GSK-3beta), or by treatment with chemical inhibitors, wortmannin and LY294002, showed little effect on the survival of Chang/HBx cells. Furthermore, IkappaBalpha (S32/36A) mutant plasmid or other NF-kappaB inhibitors, 1-pyrrolidinecarbonidithioic acid and sulphasalazine, were also shown to have little effect on the cell proliferation. By contrast, proteasome inhibitor-1 (Pro1) and MG132 enhanced the HBx-induced ER-stress response and the subsequent activation of caspase-12, -9 and -3 and reduced cell proliferation. Camptothecin (CPT), however, triggered activation of caspase-3 without induction of caspase-12, and reduced cell proliferation. In addition, CPT-induced cell death was reversed by pre-treatment with z-DEVD, a caspase-3-specific inhibitor.

CONCLUSIONS

Detailed exploitation of the regulators of caspase-3 activation could open the gate for finding an efficient target for development of anticancer therapeutics against HBx-transformed hepatocellular carcinoma.

Application of a pigment measuring device ? Mexameter�? for the differential diagnosis of vitiligo and nevus depigmentosus

BACKGROUND/PURPOSE

Vitiligo and nevus depigmentosus (ND) present similar hypopigmented macules with significantly different prognoses. Although the distinction between the two diseases is important, differential diagnosis relies on medical history and physical examination, which is far from decisive in some cases. The Mexameter is an objective skin color-measuring device, and has been reported to provide a reproducible and sensitive means of quantifying small skin color differences. In this study, we investigated the usefulness of a Mexameter for discriminating these diseases.

METHODS

A selection of 202 hypopigmented skin lesions (182 from vitiligo and 20 from ND) were the objects of this study. Using a Mexameter, MIs were obtained from lesions and symmetrically located control skin. RMIs, ratios of the MIs of lesional skins to control skins, were calculated.

RESULTS

The mean MIs and RMIs were significantly different for vitiligo and ND. The mean RMI of ND lesions was 74+/-13, which was significantly higher than that of vitiligo lesions (50+/-24). No ND lesion had an RMI of <50%.

CONCLUSION

This study shows that the Mexameter, an objective pigment-measuring device, can be used to achieve a more accurate diagnosis of hypopigmentary disorders, and that the relative melanin index (RMI), which represents the relative pigment levels, might be a more effective parameter than the melanin index (MI) itself for comparing pigmentation differences.

Identification of Lps2 as a key transducer of MyD88-independent TIR signalling

In humans, ten Toll-like receptor (TLR) paralogues sense molecular components of microbes, initiating the production of cytokine mediators that create the inflammatory response. Using N-ethyl-N-nitrosourea, we induced a germline mutation called Lps2, which abolishes cytokine responses to double-stranded RNA and severely impairs responses to the endotoxin lipopolysaccharide (LPS), indicating that TLR3 and TLR4 might share a specific, proximal transducer. Here we identify the Lps2 mutation: a distal frameshift error in a Toll/interleukin-1 receptor/resistance (TIR) adaptor protein known as Trif or Ticam-1. Trif(Lps2) homozygotes are markedly resistant to the toxic effects of LPS, and are hypersusceptible to mouse cytomegalovirus, failing to produce type I interferons when infected. Compound homozygosity for mutations at Trif and MyD88 (a cytoplasmic TIR-domain-containing adaptor protein) loci ablates all responses to LPS, indicating that only two signalling pathways emanate from the LPS receptor. However, a Trif-independent cell population is detectable when Trif(Lps2) mutant macrophages are stimulated with LPS. This reveals that an alternative MyD88-dependent 'adaptor X' pathway is present in some, but not all, macrophages, and implies afferent immune specialization.

Blood partition and protein binding of a new neuroprotective agent for ischemia-reperfusion damage, KR-31378

The blood partition of KR-31378 between plasma and blood cells and the factors influencing the binding of the drug to 4% human serum albumin (HSA) using an equilibrium dialysis technique were evaluated. KR-31378 reached an equilibrium rapidly between plasma and blood cells of rabbit blood. The equilibrium plasma/blood cells concentration ratios were independent of initial rabbit blood concentrations of KR-31378, 1, 10 and 50 microg/ml; the values were in the range of 1.42-2.33. It took approximately 12-h incubation to reach an equilibrium between plasma and isotonic Søresen phosphate buffer of pH 7.4 containing 3% dextran ('the buffer'). The binding of KR-31378 to 4% HSA was dependent on HSA concentrations (the binding values were 25.3 and 32.0% for HSA concentrations of 2 and 5%, respectively), incubation temperature (the binding values were 48.8, 29.0 and 25.8% for 4, 22 and 37 degrees C, respectively), pHs of isotonic Sørensen phosphate buffer containing 3% dextran (the binding values were 17.7, 20.6, 22.8, 25.6 and 29.5% for buffer pHs of 5.8, 6.4, 7.0, 7.4 and 8.0, respectively) and alpha-1-acid glycoprotein (AAG) concentrations (the binding values were 25.6, 29.9, 34.4 and 50.3% for AAG concentrations of 0, 0.08, 0.16 and 0.32%, respectively).

The relationship between body mass index and the prevalence of obesity-related diseases based on the 1995 National Health Interview Survey in Korea

This study estimated the body mass index (BMI) distribution of Koreans and examined the relationship between BMI and obesity-related diseases, in particular hypertension and diabetes mellitus. We also attempted to provide primary data to determine suitable BMI cut-off points for obesity in Korea. The 1995 National Health Interview Study (NHIS) data were used to estimate BMI and the prevalence of hypertension and diabetes mellitus. A random sample of 5750 Koreans (15-69 years of age) were investigated. BMI was calculated by self-reported weights and heights. The diagnoses of hypertension and diabetes mellitus were obtained from self-reported conditions specified in response to consultations with physicians. The mean BMI was 22.6+/-2.6 kg m(-2) for males and 21.7+/-4.8 kg m(-2) for females. The prevalence of hypertension and diabetes mellitus increased with BMI. The odds ratios of the third quartile of BMI (21.9-23.8 kg m(-2)) for hypertension and diabetes mellitus compared with the first quartile were 6.04 and 3.22, respectively. The odds ratio of the fourth quartile (>23.8 kg m(-2)) of BMI was not significantly different from that of the third quartile. The risk of hypertension and diabetes mellitus increased at the third quartile of BMI (21.9-23.8 kg m(-2)), this quartile being much lower than both the current World Health Organization (WHO) BMI cut-off point of overweight of 25.0 kg m(-2), and the 90th percentile proposed in the Monica project, BMI 26.4 kg m(-2). This finding was notable considering the fact that both hypertension and diabetes mellitus occur in Koreans with lower BMIs than whites. Further studies are necessary to identify the BMI cut-off point for obesity in Korea.

Pan-caspase inhibitor zVAD enhances cell death in RAW246.7 macrophages

Even though the pan-caspase inhibitor zVAD has been widely used as an anti-apoptotic agent, inefficient prevention or even enhancement of cell death has been reported in certain cells. To further investigate its effects on cell death, three different cell types were exposed to various apoptotic stimuli in the presence or absence of zVAD. In Jurkat cells, zVAD protected against cell death induced by tumor necrosis factor (TNF), sodium nitroprusside (SNP) and etoposide, whereas in L929 cells cell death was increased. In RAW246.7 macrophages, zVAD showed similar effects as in L929 cells. However, unlike L929 cells, in which the cell death by TNF is known to be necrosis, RAW246.7 cells manifested features of apoptosis such as chromatin condensation and nuclear fragmentation. Induction of cell death by zVAD in lipopolysaccharide (LPS)-activated RAW246.7 cells also showed the same features as those observed in SNP- and etoposide-treated cells. Initiation of an apoptotic process by zVAD not only disputes the sole role of caspases in apoptosis but also suggests an anti-apoptotic function of certain caspase(s). Death of LPS-activated macrophages may be controlled by an anti-apoptotic caspase.

Characterization of the selectivity and mechanism of cytochrome P450 inhibition by dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylenedioxybiphenyl-2,2'-dicarboxylate

In vitro studies with human liver microsomes and cytochrome P450 (P450) prototype substrates were performed to characterize the selectivity and mechanism of inhibition of P450 by dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylenedioxybiphenyl-2,2'-dicarboxylate (DDB). DDB was found to be a strong inhibitor of testosterone 6beta-hydroxylation activity (CYP3A4) with a K(i) value of 0.27 +/- 0.21 microM. At higher concentrations, DDB marginally inhibited caffeine N(3)-demethylation (CYP1A2), diclofenac 4'-hydroxylation (CYP2C9), and dextromethorphan O-demethylation (CYP2D6) activities, but this compound had no effect on CYP2A6-, CYP2C19-, and CYP2E1-mediated reactions. Spectral analysis indicated that the formation of metabolite-P450 complex having absorbance at 456 nm was concentration-dependent; 5 to 33% of the total P450 was complexed in rat and human liver microsomes after a 5-min incubation with DDB. In addition, microsomal incubations with DDB in the presence of NADPH resulted in a loss of spectral P450 content, which was restored after adding K(3)Fe(CN)(6). This complex formation resulted in a time-dependent loss of CYP3A-catalyzed marker activity (testosterone 6beta-hydroxylation) in human liver microsomes. The inhibition was only partially restored upon dialysis. These results collectively suggest that formation of a metabolite-CYP3A complex with DDB was responsible for the CYP3A-selective time-dependent loss of catalytic function of CYP3A.

Nucleotide sequence of envelope protein of Japanese encephalitis virus SA14-14-2 adapted to vero cells

Live attenuated Japanese encephalitis (JE) virus SA(14)-14-2 produced in primary dog kidney cells (PDK) was adapted to Vero cells. In an effort to gain insight into the molecular basis of the biological characteristics of the SA14-14-2(Vero) strain, the 1500 nucleotide sequence encoding the envelope (E) gene which possesses major neutralizing epitopes was determined and compared with the sequences of two other attenuated JE virus strains, SA14-14-2(PHK) and SA14-14-2(PDK). The amino acid sequence of the C-terminal region (a.a. 280-500) was found to be identical for all three strains, while the N-terminal region (a.a. 1-279) shows sequence variation. The distribution of mutations in the N-terminal region was nearly the same among the three attenuated strains, suggesting that the N-terminal sequences might be related with virus-host cell specificity. However, it was found that Lys and Val (a.a. 138 and 176, respectively), known to be responsible for attenuation, are still conserved in SA(14)-14-2(Vero). Animal testing showed that SA(14)-14-2(Vero) has an attenuation phenotype similar to that of the parent SA(14)-14-2(PDK) strain in mice.

A novel anti-ischemic ATP-sensitive potassium channel (K(ATP)) opener without vasorelaxation: N-(6-aminobenzopyranyl)-N'-benzyl-N' '-cyanoguanidine analogue

This paper describes the design, synthesis, and biological evaluation of a novel anti-ischemic compound, (2S,3S,4R)-N-(6-amino-3,4-dihydro-2-dimethoxymethyl-3-hydroxy-2-methyl-2H-benzopyranyl)-N'-benzyl-N"-cyanoguanidine (33), and the structure-activity relationships leading to the discovery of this compound. Compound 33 significantly reduced the myocardial infarct zone to area at risk (IZ/AAR) in the ischemic myocardium rat model with high cardioselectivity. Since the cardioprotective effect of compound 33 is reversed by ATP-sensitive potassium channel (K(ATP)) blockers, its anti-ischemic effect appears to be at least mediated by K(ATP) opening. In addition, compound 33 shows good protective activity on neuronal cells against oxidative stress, and therefore it is suggested that compound 33 may have therapeutic potential both in cardio- and in neuroprotection.

Apoptosis by pan-caspase inhibitors in lipopolysaccharide-activated macrophages

Although apoptosis has been observed in macrophages during the course of infections, the mechanism of apoptosis in activated macrophages is not fully understood. This study shows that pan-caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (ZVAD) or t-butyloxycarbonyl-Asp-fluoromethylketone (Boc-D) caused the death of lipopolysaccharide (LPS)-activated macrophages and RAW 264.7 cells with apoptotic features. The apoptosis was also observed in lipoprotein-treated bacteria but not in CpG oligonucleotide- or flagellin-treated macrophages, indicating a difference of cellular responses downstream of different Toll-like receptors. Consistent with the induction of cell death by pan-caspase inhibitors, no activation of known caspases was detected in LPS-ZVAD-treated cells, suggesting an involvement of unknown proapoptotic caspases in the cell death. ZVAD inhibited the activation of extracellular signal-regulated kinase (ERK) and p38 but not of nuclear factor (NF)-kappa B induced by LPS, suggesting that the ZVAD-sensitive molecule lies upstream of the ERK and p38 pathways but downstream of the divergent site of NF-kappa B and mitogen-activated protein kinases. Our results demonstrate that apoptosis of macrophages induced by LPS+ZVAD is independent from the known proapoptotic caspases and suggest that activity of an unidentified ZVAD-sensitive molecule(s) is involved in the survival of LPS-activated macrophages.

Monitoring of electrokinetic removal of heavy metals in tailing-soils using sequential extraction analysis

This research focused on the monitoring of the electrokinetic removal of heavy metals from tailing-soils, and emphasizes the dependency of removal efficiencies upon their physico-chemical states, as demonstrated by the different extraction methods adopted, which included aqua regia and sequential extraction. The tailing-soils examined contained high concentrations of target metal contaminants (Cd=179mgkg(-1), Cu=207mgkg(-1), Pb=5175mgkg(-1), and Zn=7600mgkg(-1)). The removal efficiencies of the different metals were significantly influenced by their speciations, mobilities and affinities (adsorption capacities) in the soil matrix. The removal efficiencies of mobile and weakly bound fractions, such as the exchangeable fraction were more than 90% by electrokinetic treatment, but strongly bound fractions, such as the organically bound species and residual fraction were not significantly removed (less than 30% removal efficiencies). In accordance with the general sequence of mobilities of heavy metals in soils, the removal efficiencies of more mobile heavy metals (Cd, Cu, and Zn) were higher than that of less mobile heavy metal (Pb).

A purified inactivated Japanese encephalitis virus vaccine made in Vero cells

A second generation, purified, inactivated vaccine (PIV) against Japanese encephalitis (JE) virus was produced and tested in mice where it was found to be highly immunogenic and protective. The JE-PIV was made from an attenuated strain of JE virus propagated in certified Vero cells, purified, and inactivated with formalin. Its manufacture followed current GMP guidelines for the production of biologicals. The manufacturing process was efficient in generating a high yield of virus, essentially free of contaminating host cell proteins and nucleic acids. The PIV was formulated with aluminum hydroxide and administered to mice by subcutaneous inoculation. Vaccinated animals developed high-titered JE virus neutralizing antibodies in a dose dependent fashion after two injections. The vaccine protected mice against morbidity and mortality after challenge with live, virulent, JE virus. Compared with the existing licensed mouse brain-derived vaccine, JE-Vax, the Vero cell-derived JE-PIV was more immunogenic and as effective as preventing encephalitis in mice. The JE-PIV is currently being tested for safety and immunogenicity in volunteers.

Profiling of protein kinases in the neoplastic transformation of human ovarian surface epithelium

OBJECTIVE

The aim of this study was to study the pattern of protein kinase expression in a culture model of epithelial ovarian carcinogenesis.

METHODS

Cultures of normal human ovarian surface epithelium (OSE), OSE from women with BRCA1 mutations, a cell culture model of preneoplastic (SV40 T-antigen-immortalized, nontumorigenic) and neoplastic (SV40-E-cadherin transfected, tumorigenic) OSE, and three ovarian cancer cell lines were used to represent OSE phenotypes of different genetic backgrounds and at different, progressive stages of neoplastic transformation. The protein kinase network signaling was studied by Western blotting, simultaneously using multiple antibodies for specific protein kinases.

RESULTS

High levels of cGMP-dependent protein kinase were found in normal and preneoplastic OSE, but were absent in neoplastic OSE. In contrast, expression of MEK6 was detected exclusively in neoplastic OSE. The expressions of casein kinase II (CK2), p38 mitogen-activated protein kinase (MAPK), cyclin-dependent kinase, and the phosphatidylinositol 3-kinase (PI3K) effectors Akt2 and p70 S6 kinase (S6K) were several-fold higher in neoplastic OSE than in normal OSE, whereas the expressions of the MAPKs extracellular signal-regulated kinases ERK1 and -2 were unchanged. Importantly, constitutive phosphorylation of Akt2 and p70 S6K, as found in neoplastic OSE, was also observed in overtly normal OSE from women with predisposing BRCA1 gene mutations.

CONCLUSIONS

These data demonstrate that different repertoires of downstream signaling proteins, particularly those of the MEK6-p38 MAPK-CK2 pathway and the PI3K pathway, are correlated with phenotypic manifestations of a cell culture model of OSE at progressive stages in the development of ovarian cancer. Changes in PI3K effectors are already found in overtly normal OSE from women with BRCA1 mutations.

Metaxin is required for tumor necrosis factor-induced cell death

We used retrovirus insertion-mediated random mutagenesis and tumor necrosis factor (TNF) selection to generate TNF-resistant lines from L929 cells. The metaxin gene, which encodes a protein located on the outer membrane of mitochondria, was identified to be the gene disrupted in one of the resistant lines. The requirement of metaxin in TNF-induced cell death of L929 was confirmed by the restoration of TNF sensitivity after ectopic reconstitution of metaxin expression. Analysis of the cell death induced by other stimuli revealed that metaxin deficiency-mediated death resistance was selective to certain stimuli. Studies using deletion mutants of metaxin showed that mitochondrial association of metaxin is required for the function of metaxin. Over-expression of truncated metaxin lacking the mitochondria anchoring sequence mimicked metaxin deficiency in wild-type cells. Interfering with metaxin prevented TNF-induced necrotic cell death in L929 cells and apoptosis in MCF-7 cells. Our work has thus defined a novel component in the death pathway used by TNF and some other death stimuli.