Development of an External Control Arm Using Electronic Health Record-Based Real-World Data to Evaluate the Efficacy of COVID-19 Treatment

To protect people from severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection, tremendous research efforts have been made toward coronavirus disease 19 (COVID-19) treatment development. Externally controlled trials (ECTs) may help reduce their development time. To evaluate whether ECT using real-world data (RWD) of patients with COVID-19 is feasible enough to be used for regulatory decision making, we built an external control arm (ECA) based on RWD as a control arm of a previously conducted randomized controlled trial (RCT), and compared it to the control arm of the RCT. The electronic health record (EHR)-based COVID-19 cohort dataset was used as RWD, and three Adaptive COVID-19 Treatment Trial (ACTT) datasets were used as RCTs. Among the RWD datasets, eligible patients were evaluated as a pool of external control subjects of the ACTT-1, ACTT-2, and ACTT-3 trials, respectively. The ECAs were built using propensity score matching, and the balance of age, sex, and baseline clinical status ordinal scale as covariates between the treatment arms of Asian patients in each ACTT and the pools of external control subjects was assessed before and after 1:1 matching. There was no statistically significant difference in time to recovery between ECAs and the control arms of each ACTT. Among the covariates, the baseline status ordinal score had the greatest influence on the building of ECA. This study demonstrates that ECA based on EHR data of COVID-19 patients could sufficiently replace the control arm of an RCT, and it is expected to help develop new treatments faster in emergency situations, such as the COVID-19 pandemic.

Comparison of hepatotoxicity of tegoprazan, a novel potassium-competitive acid blocker, with proton pump inhibitors using real-world data: A nationwide cohort study

Background

Proton pump inhibitors (PPIs) are acid suppressants that are frequently prescribed in many countries to reduce heartburn. A potassium-competitive acid blocker (P-CAB; tegoprazan) was launched relatively recently that also inhibits gastric acid secretion. This study aimed to compare the hepatotoxicity of the six existing PPIs with P-CAB.

Methods

This retrospective cohort study was conducted between January 2019 and December 2020 and included data from the total population of 50 million inhabitants in Korea. Propensity score (PS) matching was performed using 10 variables, and the differences in hepatotoxicity between P-CAB and the six PPIs were compared in a similar distribution. The primary endpoint was hepatotoxicity which included toxic liver disease, hepatitis, hepatic failure, liver transplantation, and other liver diseases.

Results

The risk ratios (RR) of tegoprazan vs. the six PPIs (dexlansoprazole, esomeprazole, lansoprazole, omeprazole, pantoprazole, and rabeprazole) were all significant [RR: 0.70 (95% CI: 0.69-0.72), 0.81 (95% CI: 0.79-0.83), 0.61 (95% CI: 0.59-0.63), 1.17 (95% CI: 1.13-1.20), 0.61 (95% CI: 0.59-0.62), and 0.73 (95% CI: 0.71-0.75), respectively]. The risk ratio of tegoprazan vs. the six existing PPIs was 0.73 (95% CI: 0.72-0.75). The hazard ratios (HRs) of hepatotoxicity of the six PPIs to tegoprazan showed significantly higher values apart from omeprazole (HR: dexlansoprazole, 1.13; esomeprazole, 1.04; lansoprazole, 1.25; omeprazole, 0.77; pantoprazole, 1.26; rabeprazole, 1.15, respectively, and the six existing PPIs, 1.10).

Conclusion

Using a large-scale data cohort analysis consisting of 50 million Koreans, tegoprazan did not induce higher hepatotoxicity compared with the six conventional PPIs.

Long-term taxonomic and functional stability of the gut microbiome from human fecal samples

Appropriate storage of fecal samples is a critical step for unbiased analysis in human microbiome studies. The purpose of this study was to evaluate the stability of the fecal microbial community for up to 18 months. Ten healthy volunteers provided fecal samples at the Jeonbuk National University Hospital. Stool samples were stored under the following six conditions: four different storage temperatures (- 70 °C, - 20 °C, 4 °C, and room temperature [20-25 °C]) and two different collection tubes (OMNIgene-Gut and DNA/RNA shield-fecal collection tubes). The gut microbiome was analyzed with 16S rRNA sequencing. We compared the taxonomic composition, alpha diversity, beta diversity and inferred pathway abundance between the baseline and 18 months after storage. Samples collected in the DNA/RNA Shield-fecal collection tubes showed the best performance in preservation of the taxonomic composition at 18 months. Pairwise differences in alpha diversity metrics showed the least deviation from zero. The PERMANOVA test showed non-significant change of beta diversity metrics (Unweighted Unifrac: q-value 0.268; Weighted Unifrac: q-value 0.848). The functional stability was significantly well preserved in the DNA/RNA Shield-fecal collection tubes (adjusted p value < 0.05). Our results demonstrate the use of the DNA/RNA Shield-fecal collection tube as an alternative storage method for fecal samples to preserve the taxonomic and functional stability of the microbiome over a long term.

Occlusion type and posterior communicating artery patency may predict favorable outcome after endovascular thrombectomy in selective basilar top occlusion

Introduction

The top of the basilar artery is a five-branched junction, consisting of two superior cerebellar arteries (SCAs), two posterior cerebellar arteries (PCAs), and the basilar artery itself. This study aimed to investigate prognostic factors in patients with selective acute basilar top occlusion managed with mechanical thrombectomy, focusing on occlusion type and posterior communicating artery (PCoA) patency.

Methods

Eligible patients who underwent endovascular treatment (EVT) for acute basilar top occlusion were reviewed. Patterns of basilar top occlusion were categorized as types I–III according to whether the SCA and PCA were visible on angiography. The PCoA was categorized as hypoplastic or non-visible (type I), normal patency but non-visible PCA through PCoA flow (type II), and fetal type (type III).

Results

Good outcomes were observed in 50% (21/42) and mortality in 11.9% (5/42) of the cases at 90 days. Patients with good outcomes showed lower baseline National Institutes of Health Stroke Scale (NIHSS) score (P = 0.001) and a higher proportion of type III basilar top occlusion (P = 0.004) and type III PCoA (P = 0.001). Multivariable logistic analysis showed that baseline NIHSS score [odds ratio (OR), 0.84; 95% confidence interval (CI), 0.73–0.97; P = 0.017) and type III PCoA (OR, 21.54, 95% CI, 1.33–347.97; P = 0.031) were independent predictors of good functional outcomes.

Conclusion

A low initial NIHSS score and good PCoA patency were independent predictors of favorable clinical outcomes after EVT in patients with acute basilar top occlusion. Furthermore, the favorable outcome group showed a high proportion of type III basilar top occlusions.

Characterization of rhodanine derivatives as potential disease-modifying drugs for experimental mouse osteoarthritis

OBJECTIVE

This study was performed to characterize selected rhodanine derivatives as potential preclinical disease-modifying drugs for experimental osteoarthritis (OA) in mice.

METHODS

Three rhodanine derivatives, designated rhodanine (R)-501, R-502, and R-503, were selected as candidate OA disease-modifying drugs. Their effects were evaluated by intra-articular (IA) injection in OA mouse models induced by DMM (destabilization of the medial meniscus) or adenoviral overexpression in joint tissues of hypoxia-inducible factor (HIF)-2α or zinc importer ZIP8. The regulatory mechanisms impacted by the rhodanine derivatives were examined in primary-culture chondrocytes and fibroblast-like synoviocytes (FLS).

RESULTS

All three rhodanine derivatives inhibited OA development caused by DMM or overexpression of HIF-2α or ZIP8. Compared to vehicle-treated group, for example, IA injection of R-501 in DMM-operated mice reduced median OARSI grade from 3.78 (IQR 3.00-5.00) to 1.89 (IQR 0.94-2.00, P = 0.0001). R-502 and R-503 also reduced from 3.67 (IQR 2.11-4.56) to 2.00 (IQR 1.00-2.00, P = 0.0030) and 2.00 (IQR 1.83-2.67, P = 0.0378), respectively. Mechanistically, the rhodanine derivatives inhibited the nuclear localization and transcriptional activity of HIF-2α in chondrocytes and FLS. They did not bind to Zn²⁺ or modulate Zn²⁺ homeostasis in chondrocytes or FLS; instead, they inhibited the nuclear localization and transcriptional activity of the Zn²⁺-dependent transcription factor, MTF1. HIF-2α, ZIP8, and interleukin-1β could upregulate matrix-degrading enzymes in chondrocytes and FLS, and the rhodanine derivatives inhibited these effects.

CONCLUSION

IA administration of rhodanine derivatives significantly reduced OA pathogenesis in various mouse models, demonstrating that these derivatives have disease-modifying therapeutic potential against OA pathogenesis.

Changes of Atherosclerotic Plaque in Cerebral Artery Stenosis According to High-Resolution MR Imaging

Atherosclerosis can affect multiple arteries, and result in stroke and heart disease. Clinical and conventional imaging is insufficient to predict the progression of atherosclerosis. This study investigates risk factors that rely on high-resolution magnetic resonance imaging (HR-MRI). Patients with cerebral artery stenosis who had undergone HR-MRI at least twice were included. The demographics, risk factors, and proportion of patients with cerebral artery stenosis were investigated. The association between atherosclerotic plaque characteristics and the progression or regression of artery stenosis was also analyzed. A total of 42 patients were analyzed, with a median follow-up of 16.88 ± 12.53 months. The mean age of all subjects was 63.1 ± 9.15 years, and 83.3% of them were male. The incidences of stenosis of the basilar, proximal internal carotid, and middle cerebral arteries were 21.4%, 61.9%, and 16.7%, respectively. Intraplaque hemorrhage (IPH) was detected in 20 (47.6%) patients. Multivariate analysis showed that age (odds ratio (OR), 0.87; p = 0.014), smoking (OR, 0.11; p = 0.033), and IPH regression (OR, 10.13; p = 0.027) were associated with stenosis regression. The progression of IPH (OR, 115.80; p = 0.007) was associated with stenosis progression. Results suggest that IPH on HR-MRI is associated with changes in cerebral atherosclerotic stenosis.

Treatment Patterns of Type 2 Diabetes Assessed Using a Common Data Model Based on Electronic Health Records of 2000-2019

BACKGROUND

Real-world data analysis is useful for identifying treatment patterns. Understanding drug prescription patterns of type 2 diabetes mellitus may facilitate diabetes management. We aimed to analyze treatment patterns of type 2 diabetes mellitus using Observational Medical Outcomes Partnership Common Data Model based on electronic health records.

METHODS

This retrospective, observational study employed electronic health records of patients who visited Jeonbuk National University Hospital in Korea during January 2000-December 2019. Data were transformed into the Observational Medical Outcomes Partnership Common Data Model and analyzed using R version 4.0.3 and ATLAS ver. 2.7.6. Prescription frequency for each anti-diabetic drug, combination therapy pattern, and prescription pattern according to age, renal function, and glycated hemoglobin were analyzed.

RESULTS

The number of adults treated for type 2 diabetes mellitus increased from 1,867 (2.0%) in 2000 to 9,972 (5.9%) in 2019. In the early 2000s, sulfonylurea was most commonly prescribed (73%), and in the recent years, metformin has been most commonly prescribed (64%). Prescription rates for DPP4 and SGLT2 inhibitors have increased gradually over the past few years. Monotherapy prescription rates decreased, whereas triple and quadruple combination prescription rates increased steadily. Different drug prescription patterns according to age, renal function, and glycated hemoglobin were observed. The proportion of patients with HbA1c ≤ 7% increased from 31.1% in 2000 to 45.6% in 2019, but that of patients visiting the emergency room for severe hypoglycemia did not change over time.

CONCLUSION

Medication utilization patterns have changed significantly over the past 20 years with an increase in the use of newer drugs and a shift to combination therapies. In addition, various prescription patterns were demonstrated according to the patient characteristics in actual practice. Although glycemic control has improved, the proportion within the target is still low, underscoring the need to improve diabetes management.

A Randomized, Double-Blind, Placebo-Controlled Study of the Safety and Efficacy of Olanzapine for the Prevention of Chemotherapy-Induced Nausea and Vomiting in Patients Receiving Moderately Emetogenic Chemotherapy: Results of the Korean South West Oncology Group (KSWOG) Study

PURPOSE

Data on the efficacy of olanzapine in patients receiving moderately emetogenic chemotherapy (MEC) are limited. This study aimed to evaluate and compare the efficacy of olanzapine versus placebo in controlling nausea and vomiting in patients receiving MEC.

Materials and Methods

We conducted a randomized, double-blind, placebo-controlled study to determine whether olanzapine can reduce the frequency of chemotherapy-induced nausea and vomiting (CINV) and improve the quality of life (QOL) in patients receiving palonosetron and dexamethasone as prophylaxis for MEC-induced nausea and vomiting. The primary end point was complete response for the acute phase (0-24 hours after chemotherapy). The secondary end points were complete response for the delayed (24-120 hours) and overall phase (0-120 hours), proportion of significant nausea (visual analogue scale ≥ 25 mm), use ofrescue medications, and effect on QOL.

RESULTS

Fifty-six patients were randomized to the olanzapine (n=29) and placebo (n=27) groups. Complete response rates were not significantly different between the olanzapine and placebo groups in the acute (96.5% vs. 88.0%, p=0.326), delayed (69.0% vs. 48.0%, p=0.118), and overall phases (69.0% vs. 48.0%, p=0.118). However, the percentage of patients with significant nausea (17.2% vs. 44.0%, p=0.032) and the use of rescue medications (0.03±0.19 vs. 1.88±2.88, p=0.002) were lower in the olanzapine group than in the placebo. Furthermore, the olanzapine group demonstrated better QOL (p=0.015).

CONCLUSION

Olanzapine combined with palonosetron and dexamethasone significantly improved QOL and vomiting control among previously untreated patients receiving MEC, although the efficacy was limited to the reduction of the frequency of CINV.

A randomized, double-blind, placebo-controlled study of the safety and efficacy of olanzapine for the prevention of chemotherapy-induced nausea and vomiting in patients receiving moderately emetogenic chemotherapy

e21699

Background: Olanzapine was found to be effective for preventing acute and delayed emesis in patients receiving highly emetogenic chemotherapy by randomized phase 3 study. However, there is limited data for the efficacy of olanzapine combined with palonosetron and dexamethasone in patients receiving moderately emetogenic chemotherapy (MEC). Methods: We conducted randomized, double-blind, placebo-controlled study to determine whether olanzapine could reduce the frequency of CINV and improve quality of life (QOL) in patients receiving palonosetron and dexamethasone for the prophylaxis of MEC induced nausea and vomiting. Two groups received either 10 mg of olanzapine orally or matching placebo daily on days 1 through 4. The primary end point was the complete response (no emesis and no use of rescue medication) for the acute phase (0-24 hours after chemotherapy). Secondary end points included the complete responses for the delayed (24-120 hours) and overall phase (0-120 hours), proportion of significant emesis (VAS ≥ 25 mm) for overall phase, use of rescue medications, and effect on QOL by Functional Living Index-Emesis (FLIE) questionnaire. Results: Fifty-six patients were randomized and fifty-four patients were evaluable (29 assigned to olanzapine, and 25 to placebo). The complete response rate was not significant between olanzapine and placebo group in the acute (96.5% vs. 88.0%, P = 0.326), delayed (69.0% vs. 48.0%, P = 0.118), and overall phase (69.0% vs. 48.0%, P = 0.118). However, the percentage of patients with significant emesis (17.2% vs. 44.0%, P = 0.032) and the use of rescue medications (0.03±0.19 vs. 1.88±2.88, P = 0.002) were significantly lower with olanzapine than with placebo in the overall phase. Furthermore, olanzapine group experienced a better QOL than the placebo group, as reported on the FLIE questionnaire (P = 0.015). Conclusions: Olanzapine in addition to palonosetron and dexamethasone significantly improved the management of emesis and QOL among previously untreated patients receiving MEC, although the efficacy was limited to reduce the frequency of CINV. Clinical trial information: NCT02400866.

Clinical Phenotype of Diabetic Peripheral Neuropathy and Relation to Symptom Patterns: Cluster and Factor Analysis in Patients with Type 2 Diabetes in Korea

OBJECTIVES

Patients with diabetic peripheral neuropathy (DPN) is the most common complication. However, patients are usually suffering from not only diverse sensory deficit but also neuropathy-related discomforts. The aim of this study is to identify distinct groups of patients with DPN with respect to its clinical impacts on symptom patterns and comorbidities.

METHODS

A hierarchical cluster analysis and factor analysis were performed to identify relevant subgroups of patients with DPN (n = 1338) and symptom patterns.

RESULTS

Patients with DPN were divided into three clusters: asymptomatic (cluster 1, n = 448, 33.5%), moderate symptoms with disturbed sleep (cluster 2, n = 562, 42.0%), and severe symptoms with decreased quality of life (cluster 3, n = 328, 24.5%). Patients in cluster 3, compared with clusters 1 and 2, were characterized by higher levels of HbA1c and more severe pain and physical impairments. Patients in cluster 2 had moderate pain levels but disturbed sleep patterns comparable to those in cluster 3. The frequency of symptoms on each item of MNSI by "painful" symptom pattern showed a similar distribution pattern with increasing intensities along the three clusters.

CONCLUSIONS

Cluster and factor analysis endorsed the use of comprehensive and symptomatic subgrouping to individualize the evaluation of patients with DPN.

Impact of caudal block on postoperative complications in children undergoing tubularised incised plate urethroplasty for hypospadias repair: a retrospective cohort study

This study aimed to assess the association between caudal block and postoperative complications after tubularised incised plate urethroplasty. The medical records of 388 paediatric patients who underwent urethroplasty at a tertiary medical centre were analysed retrospectively. Among the 342 patients included, 216 patients received a caudal block and 72 (21.1%) patients suffered surgical complications. The number of patients having surgical complications was significantly greater among patients who received a caudal block than among patients who did not receive a caudal block (53 (24.5%) versus 19 (15.1%), respectively, p = 0.04). Based on multivariate logistic regression analysis, duration of surgery, caudal block and hypospadias types were independent risk factors for the surgical complications. Patients with caudal block had an odds ratio of 2.1 (95% CI, 1.14-3.81, p = 0.018) for the development of postoperative complications compared with patients without caudal block. This analysis demonstrates that caudal block is associated with surgical complications after tubularised incised plate urethroplasty.

Pharmacokinetic properties of two erlotinib 150 mg formulations with a genetic effect evaluation in healthy Korean subjects

BACKGROUND AND OBJECTIVE

Erlotinib is a drug used to treat non-small cell lung cancer, pancreatic cancer and several other types of cancer. It is a reversible tyrosine kinase inhibitor that acts on the epidermal growth factor receptor and inhibits cell proliferation, growth, migration, invasion and survival. This study was performed for the subsequent marketing of a test erlotinib formulation in Korea. We evaluated the comparative bioavailability and tolerability of the test and reference formulations in healthy adult volunteers.

METHODS

A total of 46 healthy male subjects were enrolled in a single-dose, randomized, open-label, two-period, two-sequence, crossover, bioequivalence study. During each treatment period, subjects received 150 mg of erlotinib in either the test or reference formulation. There was a 2-week washout period between each period. Blood samples were obtained 15 times during each period, before dosing and 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 48, 72 and 96 h after oral administration. Plasma concentrations of erlotinib were determined using liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters, including maximum plasma concentration (C(max)), area under the plasma concentration-time curve to the last sampling time (AUC(t)), AUC from time zero to infinity (AUC(∞)), and time to reach C(max) (t(max)), were measured, and all treatment-emergent adverse events and their relationships with the study medications were recorded throughout the study. An additional analysis was performed to characterize the association between the cytochrome P450 (CYP) 1A1, CYP1A2 and CYP3A4 genotypes and the erlotinib pharmacokinetic parameters.

RESULTS

A total of 41 subjects completed the study. There were no significant differences in the prevalence of adverse events between the two formulations, and there were no serious or unexpected adverse events during the study. Both formulations had very similar C(max), AUC, terminal half-life (t ½) and t(max) values. The 90% confidence intervals of the geometric least-squares mean ratios of the test to reference formulation were 1.09 (0.98-1.22) for C(max) and 1.10 (1.01-1.21) for AUCt. Statistical significance was observed between the CYP1A2*1M genotype and the erlotinib pharmacokinetic parameter, particularly C(max) (p = 0.015).

CONCLUSIONS

This study suggests that the test and reference formulations of 150 mg erlotinib have similar pharmacokinetic characteristics. Both had no major safety issues and were well-tolerated. The test formulation met the regulatory criteria for assuming bioequivalence to the reference formulation for both AUCt and C max. The additional genetic analysis demonstrated that the major metabolic enzymes of erlotinib did not significantly affect erlotinib metabolism, with the exception of CYP1A2*1M.

Pharmacokinetic comparison study of a combination containing 500 mg of Naproxen and 20 mg of Esomeprazole: a randomized, single-dose, 2-way crossover, open-label study in healthy Korean men

PURPOSE

Nonsteroidal anti-inflammatory drugs have been used for analgesic, anti-inflammatory, and antithrombotic effects, but they carry a risk of major gastrointestinal damage. This risk can be greatly reduced by the coadministration of inhibitors of gastric acid secretion, such as proton pump inhibitors. This study was performed for the subsequent marketing of a combination drug that contained 500 mg of naproxen and 20 mg of esomeprazole in Korea. We evaluated the comparative bioavailability and tolerability of the test and reference formulations in healthy men.

METHODS

A total of 60 healthy men were enrolled in this single-dose, randomized, open-label, 2-period, 2-sequence, crossover study. During each period, men received a combination of 500 mg of naproxen and 20 mg of esomeprazole for test or reference, and between each period, there was a 1-week washout period. Blood samples were obtained 21 times throughout each period before dosing and 0.17, 0.33, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 8, 10, 12, 24, 48, and 72 hours after oral administration. Plasma concentrations were determined using LC-MS/MS. The pharmacokinetic parameters, including Cmax, AUC0-t, AUC0-∞, and Tmax, were measured, and all treatment-emergent adverse events and their associations with the study medications were recorded throughout the entire study.

FINDINGS

A total of 59 men completed the study. No significant differences were found in the prevalence of AEs between the 2 formulations. In addition, there were no serious or unexpected AEs during the study. Both formulations had very similar Cmax, AUC, and t½ values, but the Tmax of naproxen appeared earlier in the test formulation than in the reference formulation and that of esomeprazole appeared later in the test formulation than in the reference formulation.

IMPLICATIONS

This study suggests that the test and reference formulations of a combination of 500 mg of naproxen and 20 mg of esomeprazole are bioequivalent in the extent of absorption and peak concentration. We anticipate that the test formulation will treat those who need relief from pain and inflammation and will decrease the risk of developing gastric ulcers. cris.nih.go.kr identifier: KCT0001117.

The validities and efficiencies of korean ADHD rating scale and korean child behavior checklist for screening children with ADHD in the community

OBJECTIVE

The purpose of this study is to examine the validity of primary screening tools for attention deficit hyperactivity disorder (ADHD) in a community-based sample of children using the Korean version of the Child Behavior Checklist (K-CBCL) and the Korean version of the ADHD Rating Scale (K-ARS).

METHODS

A large-scale community-based study for ADHD screening was conducted in the Jeollabuk province in the Republic of Korea. In 2010-2011, we surveyed a total of 49,088 first- and fourth-grade elementary school students. All of the participants in this study were assessed by the K-ARS-Parent version (K-ARS-P) and the K-ARS-Teacher version (K-ARS-T) as the primary screening instruments. The Diagnostic Interview Schedule for Children Version IV (DISC-IV) was used for confirming the diagnosis of ADHD. DISC-IV was administered to subjects who received top 10% scores in the K-ARS-P or K-ARS-T tests.

RESULTS

Of the 3,085 subjects who completed the DISC-IV, 1,215 were diagnosed as having ADHD. A reasonable level of sensitivity, specificity, and negative predictive value were obtained when the total K-ARS-P scores were ≥90th percentile. The positive predictive value and specificity increased significantly when the total K-ARS-P scores were ≥90th percentile, T scores were ≥60 in the attention problems of K-CBCL, and T scores were ≥63 in the total problems of K-CBCL.

CONCLUSION

These results suggested that the K-ARS-P could effectively serve as a primary screening tool to identify elementary school children with ADHD in the community. Also, there might be some increment in the effectiveness of K-ARS-P when combined with K-CBCL-A and K-CBCL-T as a secondary screening tool.

Analgesic efficacy of caudal dexamethasone combined with ropivacaine in children undergoing orchiopexy

BACKGROUND

Epidural administration of dexamethasone might reduce postoperative pain in adults. We evaluated whether a caudal block of 0.1 mg kg(-1) dexamethasone combined with ropivacaine improves analgesic efficacy in children undergoing day-case orchiopexy.

METHODS

This randomized, double-blind study included 80 children aged 6 months to 5 yr who underwent day-case, unilateral orchiopexy. Patients received either 1.5 ml kg(-1) of 0.15% ropivacaine (Group C) or 1.5 ml kg(-1) of 0.15% ropivacaine in which dexamethasone of 0.1 mg kg(-1) was mixed (Group D) for caudal analgesia. Postoperative pain scores, rescue analgesic consumption, and side-effects were evaluated 48 h after operation.

RESULTS

Postoperative pain scores at 6 and 24 h post-surgery were significantly lower in Group D than in Group C. Furthermore, the number of subjects who remained pain free up to 48 h after operation was significantly greater in Group D [19 of 38 (50%)] than in Group C [four of 37 (10.8%); P<0.001]. The number of subjects who received oral analgesic was significantly lower in Group D [11 of 38 (28.9%)] than in Group C [20 of 37 (54.1%); P=0.027]. Time to first oral analgesic administration after surgery was also significantly longer in Group D than in Group C (P=0.014). Adverse events after surgery including vomiting, fever, wound infection, and wound dehiscence were comparable between the two groups.

CONCLUSIONS

The addition of dexamethasone 0.1 mg kg(-1) to ropivacaine for caudal block can significantly improve analgesic efficacy in children undergoing orchiopexy. Clinical trial registration NCT01604915.

Development and validation of an LC-MS/MS method for determination of compound K in human plasma and clinical application

A rapid, sensitive and selective analytical method was developed and validated for the determination of compound K, a major intestinal bacterial metabolite of ginsenosides in human plasma. Liquid-liquid extraction was used for sample preparation and analysis, followed by liquid chromatography tandem spectrometric analysis and an electrospray-ionization interface. Compound K was analyzed on a Phenomenex Luna C18 column (100×2.00 mm, 3 μm) with the mobile phase run isocratically with 10 mM ammonium acetate-methanol-acetonitrile (5:47.5:47.5, v/v/v) at a flow rate of 0.5 mL/min. The method was validated for accuracy (relative error <12.63%), precision (coefficient of variation <9.14%), linearity, and recovery. The assay was linear over the entire range of calibration standards i.e., a concentration range of 1 ng/mL to 1,000 ng/ mL (r² >0.9968). The recoveries of compound K after liquid-liquid extraction at 1, 2, 400, and 800 ng/mL were 106.00±0.08%, 103.50±0.19%, 111.45±5.21%, and 89.62±34.46% for intra-day and 85.40±0.08%, 94.50±0.09%, 112.50±5.21%, and 95.87±34.46% for inter-day, respectively. The lower limit of quantification of the analytical method of compound K was 1 ng/ mL in human plasma. The developed method was successfully applied to a pharmacokinetic study of compound K after oral administration in ten of healthy human subjects.

Validation of the Korean version of the Eppendorf Schizophrenia Inventory as a screening measure to detect adolescents at ultra-high risk for psychosis

AIM

No validated self-report scale is available for use as a screening tool to detect non-help-seeking adolescents at ultra-high risk (UHR) for psychosis in a community setting. The study aims to examine the reliability and validity of the Korean version of the Eppendorf Schizophrenia Inventory (K-ESI) for assessing adolescents at UHR for psychosis in a community setting.

METHODS

In the first study, to confirm the reliability and discriminant validity of the K-ESI, community sample (782 adolescents, 281 young adults, 122 early and middle-aged adults) and outpatients with schizophrenia (109) were recruited. A single cross-sectional survey was performed using the K-ESI for the community sample and the K-ESI and Positive and Negative Syndrome Scale for patients. In the second study, the Korean version of Youth Self Report (K-YSR) was administered initially to 1002 students. Of the 217 students whose scores were equal to or higher than the cut-off point of the K-YSR, 120 who agreed to an in-depth evaluation were interviewed using the Comprehensive Assessment of At-Risk Mental States to confirm the predictive validity of the K-ESI.

RESULTS

The K-ESI showed good internal consistency and excellent test-retest reliability and discriminant validity. However, the factor structure in adolescents was substantially different from that of the original ESI. The best cut-off point for the K-ESI to identify UHR adolescents was 29, with a sensitivity of 77% and a specificity of 70%.

CONCLUSION

The results revealed that the K-ESI can be used as a valid and reliable instrument to identify adolescents at UHR for psychosis in a community setting.

Effects of Ficus carica paste on loperamide-induced constipation in rats

OBJECTIVE

Constipation is one of the most common gastrointestinal complaints worldwide. This study examined the effects of fig (Ficus carica L.) paste for the treatment of loperamide-induced constipation in a rat model.

METHODS

Animals were divided into one normal control group and four experimental groups (0, 1, 6, and 30 g/kg). Loperamide (2 mg/kg, twice per day) was injected intraperitoneally to induce constipation in the four experimental groups. Fig paste was administered for 4 weeks to assess its anti-constipation effects.

RESULTS

Fecal pellet number, weight and water content were increased in the fig-treated groups as compared to the control group. Reductions in body weight and increased intestinal transit length were observed in the fig-treated groups. Fecal pellet number was reduced in the distal colons of the fig-treated rats. Exercise and ileum tension increased in the experimental groups as compared to the control group. According to histological analyses, the thickness of the distal colon and areas of crypt epithelial cells that produce mucin were increased in the fig-treated groups in a dose-dependent manner.

CONCLUSION

Constipation was decreased when fig fruit was fed to rats. Specifically, fecal number, weight, and water content, as well as histological parameters such as thickness and mucin areas in the distal colon were improved. Fig treatment may be a useful therapeutic and preventive strategy for chronic constipation.

Crystallization and preliminary X-ray studies of Trp138Phe/Val185Thr xylose isomerases from Thermotoga neapolitana and Thermoanaerobacterium thermosulfurigenes

Xylose isomerases from Thermotoga neapolitana (TNXI) and Thermoanaerobacterium thermosulfurigenes (TTXI) share 70.4% sequence identity and are thermostable. The double mutants Trp138Phe/Val185Thr of TNXI and TTXI have higher catalytic efficiencies than TNXI and TTXI, respectively. The Trp138Phe/Val185Thr TNXI and TTXI mutants were overexpressed in Escherichia coli strain BL21(DE3) and purified. Crystals of the two proteins were grown with polyethylene glycol 8000 as the major precipitant by the hanging-drop vapour-diffusion method. Crystals of the TNXI mutant were obtained in the absence of substrate, in complex with glucose and in complex with fructose. Crystals of the TTXI mutant were obtained complexed with glucose. Diffraction data were collected at 1.9, 2.1 and 2.1 A resolution for the fructose-TNXI mutant, glucose-TNXI mutant and substrate-unbound TNXI mutant, respectively. The diffraction data for the glucose-TTXI mutant were collected at 2.0 A resolution. The crystals belong to the orthorhombic space groups C222(1) (TNXI mutant) and P2(1)2(1)2(1) (TTXI mutant). The TNXI and TTXI mutant crystals contain two and four monomers in the asymmetric unit, respectively.

Crystallization and preliminary X-ray crystallographic analysis of the surE protein from Thermotoga maritima

The surE protein from Thermotoga maritima is a 247-residue protein of unknown function. Its homologues are well conserved among both the eubacteria and the archaea. It has been overexpressed in soluble form in Escherichia coli. The protein has been crystallized at 296 K using 2-propanol as a precipitant. X-ray diffraction data have been collected to 1.9 A resolution using synchrotron radiation. The crystals belong to the trigonal space group P3(1)21 (or P3(2)21), with unit-cell parameters a = b = 115.96, c = 78.60 A, alpha = beta = 90, gamma = 120 degrees. The asymmetric unit contains two monomers of the surE protein, with a corresponding V(M) of 2.72 A(3) Da(-1) and a solvent content of 54.7%.

Crystallization and preliminary X-ray diffraction studies of the guanylate kinase-like domain of PSD-95 protein from rat

The PSD-95 (postsynaptic density-95) protein, one of the members of the MAGUK (membrane-associated guanylate kinase) family, is composed of three PDZ domains, one SH3 domain and one guanylate kinase-like (GK) domain. The GK domain mediates the scaffolding function of PSD-95 by protein--protein interaction. Here, the GK domain was subcloned, expressed as an intein fusion protein, purified without the intein and then crystallized at room temperature by the hanging-drop vapour-diffusion method using PEG 8000 as a precipitant. The complete native data set was collected to a resolution of 2.35 A using flash-cooling. The crystals belong to the primitive tetragonal space group P4(3) (or P4(1)), with unit-cell parameters a = b = 70.03 (4), c = 37.64 (1) A.

Crystal structures of the HslVU peptidase-ATPase complex reveal an ATP-dependent proteolysis mechanism

BACKGROUND

The bacterial heat shock locus HslU ATPase and HslV peptidase together form an ATP-dependent HslVU protease. Bacterial HslVU is a homolog of the eukaryotic 26S proteasome. Crystallographic studies of HslVU should provide an understanding of ATP-dependent protein unfolding, translocation, and proteolysis by this and other ATP-dependent proteases.

RESULTS

We present a 3.0 A resolution crystal structure of HslVU with an HslU hexamer bound at one end of an HslV dodecamer. The structure shows that the central pores of the ATPase and peptidase are next to each other and aligned. The central pore of HslU consists of a GYVG motif, which is conserved among protease-associated ATPases. The binding of one HslU hexamer to one end of an HslV dodecamer in the 3.0 A resolution structure opens both HslV central pores and induces asymmetric changes in HslV.

CONCLUSIONS

Analysis of nucleotide binding induced conformational changes in the current and previous HslU structures suggests a protein unfolding-coupled translocation mechanism. In this mechanism, unfolded polypeptides are threaded through the aligned pores of the ATPase and peptidase and translocated into the peptidase central chamber.

Crystallization and preliminary X-ray crystallographic studies of response regulator for cyanobacterial phytochrome, Rcp1

The key response-regulator gene of light regulation, rcp1, from Synechocystis sp. has been overexpressed, purified and subsequently crystallized using ammonium sulfate as a precipitant in forms suitable for X-ray crystallographic studies. A native data set was collected to a resolution of 2.5 A at cryogenic temperature. The crystals belong to the hexagonal space group P6(3), with unit-cell parameters a = b = 89.04 (5), c = 60.29 (3) A. The Matthews parameter suggests that Rcp1 crystallizes with two molecules per asymmetric unit.