Comparison of Catalyzing Properties of Bacterial 4-α-Glucanotransferases Focusing on Their Cyclizing Activity

A newly cloned 4-α-glucanotransferase (αGT) from Deinococcus geothermalis and two typical bacterial αGTs from Thermus scotoductus and Escherichia coli (MalQ) were investigated. Among 4 types of catalysis, the cyclization activity of αGTs that produces cycloamylose (CA), a valuable carbohydrate making inclusion complexes, was intensively studied. The new αGT, DgαGT, showed close protein sequence to the αGT from T. scotoductus (TsαGT). MalQ was clearly separated from the other two αGTs in the phylogenetic and the conserved regions analyses. The reaction velocities of disproportionation, cyclization, coupling, and hydrolysis of three αGTs were determined. Intriguingly, MalQ exhibited more than 100-fold lower cyclization activity than the others. To lesser extent, the disproportionation activity of MalQ was relatively low. DgαGT and TsαGT showed similar kinetics results, but TsαGT had nearly 10-fold lower hydrolysis activity than DgαGT. Due to the very low cyclizing activity of MalQ, DgαGT and TsαGT were selected for further analyses. When amylose was treated with DgαGT or TsαGT, CA with a broad DP range was generated immediately. The DP distribution of CA had a bimodal shape (DP 7 and 27 as peaks) for the both enzymes, but larger DPs of CA quickly decreased in the DgαGT. Cyclomaltopentaose, a rare cyclic sugar, was produced at early reaction stage and accumulated as the reactions went on in the both enzymes, but the increase was more profound in the TsαGT. Taken together, we clearly demonstrated the catalytic differences between αGT groups from thermophilic and pathogenic bacteria that and showed that αGTs play different roles depending on their lifestyle.

NIST Interlaboratory Study on Glycosylation Analysis of Monoclonal Antibodies: Comparison of Results from Diverse Analytical Methods

Glycosylation is a topic of intense current interest in the development of biopharmaceuticals because it is related to drug safety and efficacy. This work describes results of an interlaboratory study on the glycosylation of the Primary Sample (PS) of NISTmAb, a monoclonal antibody reference material. Seventy-six laboratories from industry, university, research, government, and hospital sectors in Europe, North America, Asia, and Australia submitted a total of 103 reports on glycan distributions. The principal objective of this study was to report and compare results for the full range of analytical methods presently used in the glycosylation analysis of mAbs. Therefore, participation was unrestricted, with laboratories choosing their own measurement techniques. Protein glycosylation was determined in various ways, including at the level of intact mAb, protein fragments, glycopeptides, or released glycans, using a wide variety of methods for derivatization, separation, identification, and quantification. Consequently, the diversity of results was enormous, with the number of glycan compositions identified by each laboratory ranging from 4 to 48. In total, one hundred sixteen glycan compositions were reported, of which 57 compositions could be assigned consensus abundance values. These consensus medians provide community-derived values for NISTmAb PS. Agreement with the consensus medians did not depend on the specific method or laboratory type. The study provides a view of the current state-of-the-art for biologic glycosylation measurement and suggests a clear need for harmonization of glycosylation analysis methods.

Trends in device utilization ratios in intensive care units over 10-year period in South Korea: device utilization ratio as a new aspect of surveillance

BACKGROUND

Device-associated infection (DAI) is an important issue related to patient safety. It is important to reduce unnecessary device utilization in order to decrease DAI rates.

AIM

To investigate the time trend of device utilization ratios (DURs) of voluntarily participating hospitals, collected over a 10-year period through the Korean National Healthcare-associated Infections Surveillance System (KONIS).

METHODS

DURs from 2006 to 2015 in 190 intensive care units (ICUs) participating in KONIS were included in this study. DURs were calculated as the ratio of device-days to patient-days. The pooled incidences of DAIs and DURs were calculated for each year of participation, and the year-wise trends were analysed.

FINDINGS

Year-wise ventilator utilization ratio (V-DUR) increased significantly from 0.40 to 0.41 (F = 6.27, P < 0.01), urinary catheter utilization ratio (U-DUR) increased non-significantly from 0.83 to 0.84 (F = 1.66, P = 0.10), and C-line utilization ratio (CL-DUR) decreased non-significantly from 0.55 to 0.51 (F = 1.62, P = 0.11). In the subgroup analysis, 'medical ICU' (F = 2.79, P < 0.01) and 'hospital with >900 beds' (F = 3.07, P < 0.01) were associated with the significant increase in V-DUR.

CONCLUSION

In Korea, V-DUR showed a significant, year-wise increasing trend. The trends for U-DUR and CL-DUR showed no significant decrease. Efforts are required to ensure the reduction of DURs.

Population genetic characterization of the Japanese oak silkmoth, Antheraea yamamai (Lepidoptera: Saturniidae), using novel microsatellite markers and mitochondrial DNA gene sequences

The Japanese oak silkmoth, Antheraea yamamai Guérin-Méneville, 1861 (Lepidoptera: Saturniidae), is an important natural resource of industrial value for silk fiber production. Owing to a lack of geographic and population genetic information, systematic domestication of An. yamamai has not been possible yet. In this study, 10 microsatellite markers developed using next-generation sequencing and two mitochondrial DNA (mtDNA) gene sequences (COI and ND4) were used to investigate the genetic variation and geographic structure of An. yamamai populations in South Korea. The two mtDNA gene sequences revealed very low total genetic variation and, consequently, low geographic variation, validating the use of more variable molecular markers. Genotyping of 76 An. yamamai individuals from nine localities in South Korea showed that the observed number of alleles at each locus ranged from 3 to 26, the polymorphism information content was 0.2990-0.9014, the observed and expected heterozygosities were 0.3252-0.9076 and 0.2500-0.9054, respectively, and F_IS was -0.654-0.520. The population-based F_IS, F_ST, R_ST, and global Mantel tests all suggested that the An. yamamai populations were overall well-interconnected, suggesting that any population can be used as a genetic source for domestication. Nevertheless, STRUCTURE analyses using microsatellite data and mtDNA sequences indicated the presence of two genetic pools in many populations, although a plausible explanation for this observation requires further studies.

Validation of the Korean National Healthcare-associated Infections Surveillance System (KONIS): an intensive care unit module report

BACKGROUND

National surveillance data should be validated to identify methodological problems within the surveillance programme and data quality issues.

AIM

To test the validity of healthcare-associated infection (HAI) rate data from the Korean National Healthcare-associated Infections Surveillance System (KONIS).

METHODS

Records from intensive care units of 12 (14.8%) of 81 participating hospitals for January-March 2014 were examined. The validation team reviewed 406 medical records of 110 patients with 114 reported HAIs - including 34 urinary tract infections (UTIs), 57 bloodstream infections (BSIs) and 23 cases of pneumonia (PNEU) - and 296 patients with no reported HAIs during one-day visits conducted in August and September 2014. The reviewers' diagnosis of HAI was regarded as the reference standard; in ambiguous cases, the KONIS Steering Committee confirmed the diagnosis of HAI.

FINDINGS

Sensitivity values for UTIs, BSIs and PNEU were 85.3%, 74.0% and 66.7%, and specificity values were 98.7%, 99.1% and 98.7%, respectively. Positive predictive values were 85.3%, 94.7% and 78.3%, and negative predictive values were 98.7%, 94.6% and 97.7%, respectively. Sensitivity for PNEU was lower than that for UTIs and BSIs. The hospitals participating in KONIS infrequently reported conditions that were not HAIs. Sensitivity for BSIs was lower in this study than in KONIS validation studies conducted in 2008 and 2010.

CONCLUSIONS

KONIS data are generally reliable; however, sensitivity for BSIs exhibited a decrease. This study shows the need for ongoing validation and continuous training of surveillance personnel to maintain the accuracy of surveillance data.

Five-year decreased incidence of surgical site infections following gastrectomy and prosthetic joint replacement surgery through active surveillance by the Korean Nosocomial Infection Surveillance System

BACKGROUND

Surveillance of healthcare-associated infection has been associated with a reduction in surgical site infection (SSI).

AIM

To evaluate the Korean Nosocomial Infection Surveillance System (KONIS) in order to assess its effects on SSI since it was introduced.

METHODS

SSI data after gastrectomy, total hip arthroplasty (THA), and total knee arthroplasty (TKA) between 2008 and 2012 were analysed. The pooled incidence of SSI was calculated for each year; the same analyses were also conducted from hospitals that had participated in KONIS for at least three consecutive years. Standardized SSI rates for each year were calculated by adjusting for SSI risk factors. SSI trends were analysed using the Cochran-Armitage test.

FINDINGS

The SSI rate following gastrectomy was 3.12% (522/16,918). There was a significant trend of decreased crude SSI rates over five years. This trend was also evident in analysis of hospitals that had participated for more than three years. The SSI rate for THA was 2.05% (157/7656), which decreased significantly from 2008 to 2012. The risk factors for SSI after THA included the National Nosocomial Infections Surveillance risk index, trauma, reoperation, and age (60-69 years). The SSI rate for TKA was 1.90% (152/7648), which also decreased significantly during a period of five years. However, the risk-adjusted analysis of SSI did not show a significant decrease for all surgical procedures.

CONCLUSION

The SSI incidence of gastrectomy and prosthetic joint replacement declined over five years as a result of active surveillance by KONIS.

Trends in the distribution and antimicrobial susceptibility of causative pathogens of device-associated infection in Korean intensive care units from 2006 to 2013: results from the Korean Nosocomial Infections Surveillance System (KONIS)

BACKGROUND

For all countries, information on pathogens causing healthcare-associated infections is important in order to develop proper strategies for preventing and treating nosocomial infections.

AIM

To assess the change in frequencies and antimicrobial resistance of pathogens causing device-associated infections (DAIs) in intensive care units (ICUs) in South Korea between July 2006 and June 2014.

METHODS

Data from the Korean Nosocomial Infections Surveillance System (KONIS) were analysed, including three major DAI types in ICUs.

FINDINGS

The frequency of Gram-negative bacteria gradually increased for central line-associated bloodstream infection (CLABSI) and ventilator-associated pneumonia (VAP) (from 24.6% to 32.6% and from 52.8% to 73.5%, respectively). By contrast, the frequency of Gram-positive bacteria decreased from 58.6% to 49.2% for CLABSI, and from 44.3% to 23.8% for VAP (P < 0.001). Staphylococcus aureus was the most frequent causative pathogen in CLABSI throughout the surveillance period, but for VAP was replaced as the most frequent pathogen by Acinetobacter baumannii as of 2010. Candida albicans was the most frequent pathogen for catheter-associated urinary tract infection. The meticillin resistance rate in S. aureus decreased from 95% to 90.2% (P < 0.001); amikacin resistance in Klebsiella pneumoniae and Escherichia coli decreased from 43.8% to 14.7% and from 15.0% to 1.8%, respectively (P < 0.001); imipenem resistance in A. baumannii increased from 52.9% to 89.8% (P < 0.001).

CONCLUSION

The proportion of Gram-negative bacteria as nosocomial pathogens for CLABSI and VAP has increased. The prevalence of A. baumannii causing DAIs in Korean ICUs has increased rapidly, as has the rate of carbapenem resistance in these bacteria.

A possible role of serum uric acid as a marker of metabolic syndrome

BACKGROUND/AIMS

The association between serum uric acid (SUA) levels and metabolic syndrome (MetS) has recently been reported in several cross-sectional and longitudinal studies. We investigated SUA as a biomarker to predict future development of MetS in healthy Korean men without diabetes or hypertension and determined the optimal cut-off levels of SUA.

METHODS

A retrospective cohort study was conducted using data from healthy men who received a general health check-up in 2003. A total of 1809 participants free of MetS, diabetes and hypertension was enrolled. Participants were classified into three groups based on SUA levels: group 1 (<5.5 mg/dL), group 2 (5.5-6.9 mg/dL) and group 3 (≥7.0 mg/dL).

RESULTS

During 13,802 person-years of follow up, 127 participants developed MetS. After adjusting for multiple associated parameters, SUA was significantly associated with incident MetS (hazard ratios comparing groups 2 and 3 vs group 1, 2.45 and 3.47 respectively; P < 0.001). In receiver operating characteristic curve analysis, the optimal cut-off level for SUA to predict the development of MetS was 6.5 mg/dL.

CONCLUSION

Our results indicate that an increased level of SUA, even within the normal range, is associated with future development of MetS in healthy middle-aged men.

Contrast-enhanced angiographic cone-beam computed tomography without pre-diluted contrast medium

INTRODUCTION

Contrast-enhanced cone-beam computed tomography (CBCT) has been introduced and accepted as a useful technique to evaluate delicate vascular anatomy and neurovascular stents. Current protocol for CBCT requires quantitative dilution of contrast medium to obtain adequate quality images. Here, we introduce simple methods to obtain contrast-enhanced CBCT without quantitative contrast dilution.

METHODS

A simple experiment was performed to estimate the change in flow rate in the internal carotid artery during the procedure. Transcranial doppler (TCD) was used to evaluate the velocity change before and after catheterization and fluid infusion. In addition, 0.3 cm(3)/s (n = 3) and 0.2 cm(3)/s (n = 7) contrast infusions were injected and followed by saline flushes using a 300 mmHg pressure bag to evaluate neurovascular stent and host arteries.

RESULTS

Flow velocities changed -15 ± 6.8 % and +17 ± 5.5 % from baseline during catheterization and guiding catheter flushing with a 300 mmHg pressure bag, respectively. Evaluation of the stents and vascular structure was feasible using this technique in all patients. Quality assessment showed that the 0.2 cm(3)/s contrast infusion protocol was better for evaluating the stent and host artery.

CONCLUSION

Contrast-enhanced CBCT can be performed without quantitative contrast dilution. Adequate contrast dilution can be achieved with a small saline flush and normal blood flow.

Trends in the incidence rate of device-associated infections in intensive care units after the establishment of the Korean Nosocomial Infections Surveillance System

BACKGROUND

The effectiveness of continuous nationwide surveillance on healthcare-associated infections should be investigated in each country.

AIM

To assess the rate of device-associated infections (DAIs) in intensive care units (ICUs) since the establishment of the Korean Nosocomial Infections Surveillance System (KONIS).

METHODS

Nationwide data were obtained on the incidence rate of DAI in ICUs reported to KONIS by all participating hospitals. The three major DAIs were studied: ventilator-associated pneumonia (VAP), central line-associated bloodstream infection (CABSI), and catheter-associated urinary tract infection (CAUTI). The pooled and year-wise incidence rates (cases per 1000 device-days) of these DAIs were determined for the period 2006 and 2012. In addition, data from institutions that had participated in KONIS for at least three consecutive years were analysed separately.

FINDINGS

The number of ICUs participating in KONIS gradually increased from 76 in 2006 to 162 in 2012. Between 2006 and 2012, the incidence rate per 1000 device-days for VAP decreased significantly from 3.48 to 1.64 (F = 11, P < 0.01), for CAUTI the rate decreased non-significantly from 1.85 to 1.26 (F = 2.02, P = 0.07), and for CABSI the rate also decreased non-significantly from 3.4 to 2.57 (F = 1.73, P = 0.12). In the 132 ICUs that had participated in KONIS for at least three consecutive years, the VAP rate significantly decreased from the first year to third year (F = 20.57, P < 0.01), but the rates of CAUTI (F = 1.06, P = 0.35) and CABSI (F = 1.39, P = 0.25) did not change significantly.

CONCLUSION

The decreased incidence rate of VAP in ICUs in Korea might be associated with the continuous prospective surveillance provided by KONIS.

NLRP3 inflammasome activation by mitochondrial ROS in bronchial epithelial cells is required for allergic inflammation

Abnormality in mitochondria has been suggested to be associated with development of allergic airway disorders. In this study, to evaluate the relationship between mitochondrial reactive oxygen species (ROS) and NLRP3 inflammasome activation in allergic asthma, we used a newly developed mitochondrial ROS inhibitor, NecroX-5. NecroX-5 reduced the increase of mitochondrial ROS generation in airway inflammatory cells, as well as bronchial epithelial cells, NLRP3 inflammasome activation, the nuclear translocation of nuclear factor-κB, increased expression of various inflammatory mediators and pathophysiological features of allergic asthma in mice. Finally, blockade of IL-1β substantially reduced airway inflammation and hyperresponsiveness in the asthmatic mice. These findings suggest that mitochondrial ROS have a critical role in the pathogenesis of allergic airway inflammation through the modulation of NLRP3 inflammasome activation, providing a novel role of airway epithelial cells expressing NLRP3 inflammasome as an immune responder.

Abstract P5-03-12: Prognostic role of stem cell markers in triple-negative breast cancer (TNBC)

Introduction: Triple-negative breast cancer (TNBC) is among the most aggressive types of breast cancer with frequent recurrence and death despite chemotherapy. Studies have shown that cancer stem cells play a key role in many of the drug resistant cancers including TNBC. In this study, we report the expressions of four stem cell markers in 158 TNBC tumors.

Design: Clinicopathological data were obtained from 158 triple negative breast cancers between 2002 and 2010. Tissue microarray was constructed and immunohistochemistry stains (IHC) for CD44 and CD24, CD 133 and ALDH1 were performed using the streptavidin-biotin method. Each set of TNBC consists of normal, ductal carcinoma in situ and invasive areas for assessment of IHC stains. Statistical analysis was done on the following parameters: Histological types, modified Bloom and Richardson grades, lymph-vascular invasion, lymph node status, tumor size, Ki67, presence of lymphocytic host response, age &gt;50 or &lt;50, BRCA status, prognosis (recurrence and death) and chemotherapeutic response. P values less than 0.05 were considered statistically significant.

Results: the mean age of this cohort of TNBC patients was 55 with 64% white, 13.2% black, 12.6% Asian/Pacific, 3.8% Hispanic/Latino and 1.9% other. The majority of these tumors (82.3%) were grade 3, 15.2% were grade 2, and less than 1% was grade 1. CD24, CD44 and CD133 expressions were significantly higher in TNBC than in normal breast tissues (p = 5.53 e-10, p = 1.14 e-11, p = 2.25 e-08 respectively). While both CD24 and CD133 expressions predicted poor survival (p = 0.073 and p = 0.043 respectively), neither was associated with recurrence. In contrast to CD24, CD44 and CD133 expressions, ALDH-1 expression was rare in TNBC and surrounding normal tissues. When expressed, ALDH-1 was associated with poor survival but cases were too few to reach significance. None of the four stem cell markers studied were associated with any of the conventional histopathologic features and BRCA1 or BRCA2 mutations.

Conclusions: Our study suggests that stem cell marker(s) may be prognostically important in TNBC patients. When it is fully characterized it may provide new insight in developing effective therapeutic strategies targeting stem cell related signaling pathways.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-03-12.

Comparison of clinical outcomes after conservative and surgical treatment of isolated anastomotic leaks after esophagectomy for esophageal cancer

The clinical course and outcome of isolated anastomotic leaks (IALs) after esophagectomy are significantly different from those of necrotic leaks. The purpose of this study was to investigate the clinical features, diagnosis, treatment, and long-term outcome in patients with IALs after esophagectomy with reconstruction for esophageal cancer. A total of 663 patients underwent esophagectomy with esophageal reconstruction because of esophageal cancer between 2000 and 2010 at the Seoul Asan Medical Center. IALs occurred in 23 patients (3.5%). All patients with IAL were male, with a median age of 61 years. Patients with IAL were divided into three groups based on their clinical course. group A comprised patients who had definite clinical symptoms and/or signs indicating mediastinal contamination or leak before routine contrast esophagography was performed. Groups B and C comprised patients who had no definite clinical symptoms and/or signs of leaks before the routine contrast examination. Furthermore, group B contained those patients who resumed oral intake because no leak was found in the routine contrast examination and was diagnosed some days after resuming oral intake. Group C contained those patients who kept fasting because the leak was found in the routine contrast examination. The median follow-up period was 30 months. The mean time to closure of the IAL was 70.1 ± 96.0 days (range 4-364). There was a 72.7% overall closure rate within 60 days. By univariate analysis, the mean time to closure of the IAL was found to be significantly longer for group A patients or in cases where the patients had an uncontained leak, leukocytosis, or empyema. However, there was no statistically significant differences in age, neoadjuvant treatment, site of anastomosis (cervical vs. thoracic), fever, or treatment of the leak. By multivariate analysis, group A was found to be an independent predictive factor for the time to closure of the IAL. Repeat contrast studies revealed no anastomotic leaks in 18 patients and the formation of contained fistula in four cases (excluding one patient who died in hospital). The four patients with a contained fistula showed no clinical symptoms or signs, and tolerated resumed oral intake. IALs were resolved in most cases with low leak-related mortality, and resolution of the leaks occurred within 2 months in the majority of patients.

Association of depression and anxiety with reduced quality of life in patients with predialysis chronic kidney disease

AIM

Although depression and anxiety are the most common psychological problems among dialysis patients, little is known about the association between depression, anxiety and quality of life (QOL) in patients with predialysis chronic kidney disease (CKD). Therefore, we assessed the prevalence of depression and anxiety, and their association with QOL in patients with predialysis CKD.

METHODS

Two hundred and eight predialysis patients (male 61.1%) with a mean age of 55.7 ± 13.7 years and an estimated glomerular filtration rate < 60 ml/min/1.73 m(2) were enrolled. Depression and anxiety were assessed with the Hospital Anxiety and Depression Scale. Patients with anxiety and depression scores ≥ 8 were diagnosed with anxiety and depression disorders respectively. The WHOQOL-BREF questionnaire was used to assess patient QOL.

RESULTS

The prevalence of depression (47.1%) and anxiety (27.6%) did not differ across CKD stages. Depression correlated positively with age, employment, income, education, comorbidity index, haemoglobin level, albumin concentration and anxiety score, and negatively with all WHOQOL-BREF domain scores. Anxiety correlated significantly with QOL, but not with socioeconomic factors. In a multiple regression analysis, haemoglobin level, anxiety and QOL were independent factors associated with depression. In a linear regression analysis, depression and anxiety independently correlated with QOL after we adjusted for age, alcohol use, employment, income, education, haemoglobin level and albumin concentration.

CONCLUSIONS

Patients with predialysis CKD have a high prevalence of depression and anxiety, which are associated with reduced QOL. Early detection of depression and anxiety and active interventions should be considered to improve the QOL of these patients.

Prediction of response to entecavir therapy in patients with HBeAg-positive chronic hepatitis B based on on-treatment HBsAg, HBeAg and HBV DNA levels

Quantitative hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) assays are emerging as effective tools of on-treatment predictors of response to antiviral agents, in addition to monitoring serum HBV DNA levels. However, the dynamic relationship between quantitative HBsAg, as well as HBeAg and HBV DNA, and the predictability of subsequent clinical outcomes during entecavir (ETV) therapy remain unclear. Eighty-two patients with HBeAg-positive chronic hepatitis B (CHB) received ETV therapy for ≥3 years. Virologic response (VR) after 3 years of ETV therapy was achieved in 73 (89.0%) patients. Among baseline and on-treatment factors, on-treatment HBV DNA levels performed better with respect to the prediction of response than HBsAg and HBeAg levels. Especially, the performance of absolute values of HBV DNA with respect to response was superior to HBV DNA decline from the baseline. The best predictive value was an absolute HBV DNA level of 2.3 log(10) IU/mL at month 6 (areas under the curve [AUROC], 0.977; 95% CI, 0.940-1.000; P < 0.001). HBeAg seroconversion after 3 years of therapy was achieved in 26 (31.7%) patients. On-treatment HBeAg levels performed better with respect to the prediction of seroconversion than HBsAg and HBV DNA levels. The best cut-off value for the HBeAg level at month 12 for the prediction of seroconversion was 0.62 log(10) PEIU/mL. Although the HBsAg level at baseline is often used to predict the antiviral potency of entecavir, on-treatment HBV DNA and HBeAg levels are more helpful for prediction of subsequent clinical outcomes in HBeAg-positive CHB patients with entecavir treatment.

Prediction of response to entecavir therapy in patients with HBeAg-positive chronic hepatitis B based on on-treatment HBsAg, HBeAg and HBV DNA levels

Quantitative hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) assays are emerging as effective tools of on-treatment predictors of response to antiviral agents, in addition to monitoring serum HBV DNA levels. However, the dynamic relationship between quantitative HBsAg, as well as HBeAg and HBV DNA, and the predictability of subsequent clinical outcomes during entecavir (ETV) therapy remain unclear. Eighty-two patients with HBeAg-positive chronic hepatitis B (CHB) received ETV therapy for ≥3 years. Virologic response (VR) after 3 years of ETV therapy was achieved in 73 (89.0%) patients. Among baseline and on-treatment factors, on-treatment HBV DNA levels performed better with respect to the prediction of response than HBsAg and HBeAg levels. Especially, the performance of absolute values of HBV DNA with respect to response was superior to HBV DNA decline from the baseline. The best predictive value was an absolute HBV DNA level of 2.3 log(10) IU/mL at month 6 (areas under the curve [AUROC], 0.977; 95% CI, 0.940-1.000; P < 0.001). HBeAg seroconversion after 3 years of therapy was achieved in 26 (31.7%) patients. On-treatment HBeAg levels performed better with respect to the prediction of seroconversion than HBsAg and HBV DNA levels. The best cut-off value for the HBeAg level at month 12 for the prediction of seroconversion was 0.62 log(10) PEIU/mL. Although the HBsAg level at baseline is often used to predict the antiviral potency of entecavir, on-treatment HBV DNA and HBeAg levels are more helpful for prediction of subsequent clinical outcomes in HBeAg-positive CHB patients with entecavir treatment.

Additional effects of bisphenol A and paraben on the induction of calbindin-D(9K) and progesterone receptor via an estrogen receptor pathway in rat pituitary GH3 cells

There are concerns about the combined estrogenic effects of chemicals since mixtures of these chemicals exist in our environment. This study investigated potential additional interactions between bisphenol A (BPA) and isobutylparaben (IBP), which are major xenoestrogens used in the manufacture of plastics, cosmetics, drugs, and other products. The combined effects of these two chemicals were analyzed by measuring the expression of calbindin-D(9k) (CaBP-9k) in rat pituitary cancer GH3 cells. GH3 cells were treated with single and combination doses of both chemicals (BPA single doses: 10(-7), 10(-6) and 10(-5) M; IBP single doses: 10(-7), 10(-6) and 10(-5) M, and each of the BPA and IBP doses combined). Prior to treatment, cells were temporarily transfected with a plasmid containing an ERE-luciferase reporter gene. Luciferase activity was measured as an indicator of ER activation by 17β-estradiol (E2), BPA, and IBP. BPA (10(-5) M) combined with IBP (10(-7) M and 10(-6) M) induced a significant increase in the luciferase activity. Twenty-four hours after treatment, dose-dependent effects were observed in both single and combined dose groups, and several combination doses induced significant increases in the expression of CaBP-9k and progesterone receptor (PR) at both transcriptional and translational levels. Pre-treatment with ICI 182,780, a pure estrogen antagonist, significantly reversed BPA- and IBP-induced CaBP-9k and PR upregulation in GH3 cells. Taken together, these results indicate that BPA and IBP may have additionally increased estrogenic potency via an estrogen receptor-mediated pathway.

Risk factors for device-associated infection related to organisational characteristics of intensive care units: findings from the Korean Nosocomial Infections Surveillance System

Device-associated infections (DAIs) have been the major causes of morbidity and mortality of patients in intensive care units (ICUs). This study evaluated the risk factors for DAIs in ICUs. Ninety-six medical or surgical ICUs of 56 hospitals participated in the Korean Nosocomial Infections Surveillance System between July 2007 and June 2008. The occurrence of catheter-associated urinary tract infection (CAUTI), central line-associated bloodstream infection (CABSI), and ventilator-associated pneumonia (VAP) were monitored and DAI rates were calculated. Data associated with ICU characteristics were collected and Poisson regression was used for statistical analysis. Rates of CAUTI, CABSI, and VAP were 3.87 per 1000 urinary catheter days, 2.23 per 1000 central line days, and 1.89 per 1000 mechanical ventilator days, respectively. Rates of CAUTI were higher in ICUs in Seoul (P=0.032) and ICUs of major teaching hospitals (P=0.010). The ICUs of university-affiliated hospitals showed lower CAUTI rates (P=0.013). CABSI rates were higher in Seoul (P=0.001) and in medical ICUs (P=0.026). VAP rates were lower in ICUs of hospitals with more than 900 beds compared with hospitals with 400-699 beds (P=0.026). VAP rates were higher in surgical ICUs (P<0.0001) and increased 1.13-fold with each 100-unit increase in beds per infection control professional (P=0.003). The organisational and institutional characteristics of ICUs may influence DAI rates and there is a need for improvement in the incidence of VAP, CAUTI or CABSI.

Phosphoinositide 3-kinase δ inhibitor suppresses interleukin-17 expression in a murine asthma model

Phosphoinositide 3-kinases (PI3Ks) contribute to the pathogenesis of asthma by regulating the activation of inflammatory mediators, inflammatory cell recruitment and immune cell function. Recent findings have indicated that PI3Ks also regulate the expression of interleukin (IL)-17, which has been recognised as an important cytokine involved in airway inflammation. In the present study, we investigated a role of PI3Kδ in the regulation of IL-17 expression in allergic airway disease using a murine model of asthma. After ovalbumin inhalation, administration of a selective p110δ inhibitor, IC87114, significantly attenuated airway infiltration of total cells, lymphocytes, neutrophils and eosinophils, as well as airway hyperresponsiveness, and attenuated the increase in IL-17 protein and mRNA expression. Moreover, IC87114 reduced levels of IL-4, -5 and -13, expression of keratinocyte chemoattractant protein and mRNA, and nuclear factor (NF)-κB activity. In addition, a NF-κB inhibitor, BAY 11-7085 substantially reduced the increase in IL-17 protein levels. Our results also showed that inhibition of IL-17 activity with an anti-IL-17 antibody remarkably reduced airway inflammation and hyperresponsiveness. These findings suggest that inhibition of the p110δ signalling pathway suppresses IL-17 expression through regulation of NF-κB activity and, thus, has therapeutic potential in asthma.

The relationship between adipokines, metabolic parameters and insulin resistance in patients with metabolic syndrome and type 2 diabetes

This study was designed to investigate the relationship between adipokines in metabolic syndrome and insulin resistance. Sixty male and female subjects with or without metabolic syndrome and type 2 diabetes were included. The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Compared with lean control subjects, patients with metabolic syndrome and type 2 diabetes had lower circulating levels of total adiponectin and high molecular weight (HMW) adiponectin, and higher levels of leptin and interleukin-6 (IL-6). Total and HMW adiponectin and the adiponectin/leptin (A/L) ratio were negatively correlated with HOMA-IR. After adjusting for age and sex, leptin, IL-6 and tumour necrosis factor-alpha (TNF-alpha) were positively correlated with HOMA-IR. After also adjusting for body mass index, HOMA-IR was found to be independently associated with leptin, A/L ratio and TNF-alpha levels. In conclusion, decreased total adiponectin and HMW adiponectin and increased leptin and IL-6 levels are characteristic of patients with metabolic syndrome and type 2 diabetes.

Homozygous CDA*3 is a major cause of life-threatening toxicities in gemcitabine-treated Japanese cancer patients

Among 242 Japanese pancreatic cancer patients, three patients (1.2%) encountered life-threatening toxicities, including myelosuppression, after gemcitabine-based chemotherapies. Two of them carried homozygous CDA*3 (CDA208G>A [Ala70Thr]), and showed extremely low plasma cytidine deaminase activity and gemcitabine clearance. Our results suggest that homozygous *3 is a major factor causing gemcitabine-mediated severe adverse reactions among the Japanese population.

l-Ascorbic acid 2-phosphate promotes elongation of hair shafts via the secretion of insulin-like growth factor-1 from dermal papilla cells through phosphatidylinositol 3-kinase

BACKGROUND

l-Ascorbic acid 2-phosphate (Asc 2-P), a derivative of l-ascorbic acid, promotes elongation of hair shafts in cultured human hair follicles and induces hair growth in mice.

OBJECTIVES

To investigate whether the promotion of hair growth by Asc 2-P is mediated by insulin-like growth factor-1 (IGF-1) and, if so, to investigate the mechanism of the Asc 2-P-induced IGF-1 expression.

METHODS

Dermal papilla (DP) cells were cultured and IGF-1 level was measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay after Asc 2-P treatment in the absence or presence of LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor. Also, hair shaft elongation in cultured human scalp hair follicles and proliferation of cocultured keratinocytes were examined after Asc 2-P treatment in the absence or presence of neutralizing antibody against IGF-1. In addition, keratinocyte proliferation in cultured hair follicles after Asc 2-P treatment in the absence or presence of LY294002 was examined by Ki-67 immunostaining.

RESULTS

IGF-1 mRNA in DP cells was upregulated and IGF-1 protein in the conditioned medium of DP cells was significantly increased after treatment with Asc 2-P. Immunohistochemical staining showed that IGF-1 staining is increased in the DP of cultured human hair follicles by Asc 2-P. The neutralizing antibody against IGF-1 significantly suppressed the Asc 2-P-mediated elongation of hair shafts in hair follicle organ culture and significantly attenuated Asc 2-P-induced growth of cocultured keratinocytes. LY294002 significantly attenuated Asc 2-P-inducible IGF-1 expression and proliferation of follicular keratinocytes in cultured hair follicles.

CONCLUSIONS

These data show that Asc 2-P-inducible IGF-1 from DP cells promotes proliferation of follicular keratinocytes and stimulates hair follicle growth in vitro via PI3K.

Cardiovascular autonomic dysfunction predicts acute ischaemic stroke in patients with Type 2 diabetes mellitus: a 7-year follow-up study

AIMS

We investigated whether cardiovascular autonomic neuropathy (CAN) is associated with acute ischaemic stroke in patients with Type 2 diabetes.

METHODS

From 1999 to 2000, cardiovascular autonomic function tests were conducted in patients with Type 2 diabetes (n = 1458). Patients were followed up between 2006 and 2007. Standard tests for CAN measured heart rate variability parameters [expiration-to-inspiration (E/I) ratio, responses to the Valsalva manoeuvre and standing]. Using the American Diabetes Association criteria, the CAN scores were determined from the results of each test as follows: 0 = normal, 1 = abnormal (total maximum score 3). We assessed the development of acute ischaemic stroke events.

RESULTS

The prevalence of CAN at baseline was 55.7% (E/I 17.1%, Valsalva 39.4%, posture 27.3%) (n = 1126). During follow-up, 131 patients (11.6%) developed acute ischaemic stroke. The vascular events were more frequent in older patients (P < 0.001) and in those with diabetes of longer duration (P = 0.022), hypertension (P < 0.001) or diabetic retinopathy (P = 0.03) than in patients without vascular events. Patients with ischaemic stroke had higher creatinine levels (P = 0.045) and higher urine albumin excretion (P = 0.025) than those of patients without stroke. Cox proportional hazard regression analysis revealed that the CAN score was associated with the development of acute ischaemic stroke (total score 0 vs. 3, adjusted hazard ratio 2.7, 95% CI 1.3-5.5, P = 0.006).

CONCLUSION

Cardiovascular autonomic dysfunction was significantly associated with the development of ischaemic stroke in patients with Type 2 diabetes.

Anatomic results and complications of stent-assisted coil embolization of intracranial aneurysms

SUMMARY

The purpose of this study was to evaluate and report our anatomic results and complications associated with stent-assisted coil embolization of intracranial aneurysms using the Neuroform stent. From September 2003 to August 2007, 127 consecutive patients (ruptured 50, 39.4%; unruptured 77, 60.6%) underwent 129 stent-assisted coil embolization procedures to treat 136 aneurysms at our institution. Anatomic results at follow-up, procedure-related complications, and morbidity/mortality were retrospectively reviewed. Stent deployment was successful in 128 out of 129 procedures (99.2%). Forty-seven patients presented with 53 procedure-related complications (37.0%, 47/127). Thromboembolic events (n=17, 13.4%) were the most common complications, followed by intraoperative rupture (n=8, 6.3%), coil herniation (n=5, 3.9%), and postoperative rupture (n=4, 3.1%). For thromboembolic events, acute intra-procedural instent thromboses were observed in two patients and subacute or delayed in-stent thromboses in three patients. Overall mortality rate was 16.5% (21/127) and procedure-related morbidity and mortality rates were 5.5% (7/127) and 8.7% (11/127) retrospectively. Patients with poor grade subarachnoid hemorrhage (Hunt and Hess grade IV or V; 25/127, 19.7%) exhibited 56% (14/25) overall mortality rate and 24% (6/25) procedure-related mortality rate. Immediate angiographic results showed complete occlusion in 31.7% of aneurysms, near-complete occlusion in 45.5%, and partial occlusion in 22.8%. Sixty nine patients in 70 procedures with 77 aneurysms underwent angiographic followup at six months or later. Mean follow-up period was 13.7 months (6 to 45 months). Complete occlusion was observed in 57 aneurysms (74.0%) and significant in-stent stenosis was not found. Thromboembolism and intra/postoperative aneurysm ruptures were the most common complications and the main causes of procedure-related morbidity and mortality. Patients with poor grade subarachnoid hemorrhage showed poor clinical outcomes. Since most complications were induced by stent manipulation and deployment, it is mandatory to utilize these devices selectively and cautiously. While the follow- up angiographic results are promising, further studies are essential to evaluate safety, efficacy, and durability of the Neuroform stent.

Interactions between CB(1) receptors and TRPV1 channels mediated by 12-HPETE are cytotoxic to mesencephalic dopaminergic neurons

BACKGROUND AND PURPOSES

We recently proposed the existence of neurotoxic interactions between the cannabinoid type 1 (CB(1)) receptor and transient receptor potential vanilloid 1 (TRPV1) channels in rat mesencephalic cultures. This study seeks evidence for the mediator(s) and mechanisms underlying the neurotoxic interactions between CB(1) receptors and TRPV1 in vitro and in vivo.

EXPERIMENTAL APPROACH

The mediator(s) and mechanism(s) for the interactions between CB(1) receptors and TRPV1 were evaluated by cell viability assays, immunocytochemistry, Fura-2 calcium imaging, mitochondrial morphology assay, ELISA and Western blot assay in vitro in neuron-enriched mesencephalic cultures. Injections into the substantia nigra and subsequent cell counts were also used to confirm these interactions in vivo.

KEY RESULTS

The neurotoxic interactions were mediated by 12(S)-hydroperoxyeicosatetraenoic acid (12(S)-HPETE), an endogenous TRPV1 agonist. CB(1) receptor agonists (HU210 and WIN55,212-2) increased the level of 12(S)-hydroxyeicosatetraenoic acid (12(S)-HETE), a downstream metabolite of 12(S)-HPETE, which stimulates TRPV1-mediated death of mesencephalic neurons, both in vitro and in vivo. The neurotoxicity was mediated by increased intracellular Ca(2+) concentration ([Ca(2+)](i)) through TRPV1, consequently leading to mitochondrial damage and was attenuated by baicalein, a 12-lipoxygenase inhibitor.

CONCLUSION AND IMPLICATIONS

Activation of CB(1) receptors in rat mesencephalic neurons was associated with biosynthesis of 12(S)-HPETE, which in turn stimulated TRPV1 activity, leading to increased [Ca(2+)](i), mitochondrial damage and neuronal death.

Using 100% Oxygen does not Alter the Cardiovascular Autonomic Regulation during Non-invasively Simulated Haemorrhage in Healthy Volunteers

We tested the effect of 100% oxygen on heart rate (HR), arterial blood pressure (ABP), cardiac output (CO), stroke volume (SV), total peripheral resistance (TPR), HR variability (HRV), systolic blood pressure variability (SBPV) and baroreflex sensitivity (BRS) in 20 healthy volunteers during simulated haemorrhage induced by −40 mmHg lower body negative pressure (LBNP). HRV in the high frequency region (HRVHF), BRS, ABP and TPR were significantly increased, SBPV in the low frequency region (SBPVLF), CO and SV were unchanged, and HR was significantly decreased by 100% oxygen administration during normovolaemia. HRVHF, BRS, CO and SV were significantly decreased, SBPVLF and ABP were unchanged, and HR and TPR were significantly increased by LBNP during 21% or 100% oxygen administration. There were no significant differences in cardiovascular autonomic and haemodynamic responses to LBNP during 21% or 100% oxygen administration, suggesting that 100% oxygen does not alter normal cardiovascular autonomic responses during simulated haemorrhage.

Inhibition of VEGF blocks TGF-beta1 production through a PI3K/Akt signalling pathway

Vascular endothelial growth factor (VEGF) is a mediator of airway inflammation and remodelling in asthma. Transforming growth factor (TGF)-beta(1) plays pivotal roles in diverse biological processes, including tissue remodelling and repair in a number of chronic lung diseases. However, there are few studies elucidating the interactions between VEGF and TGF-beta(1) in allergic airway disease. A murine model of allergic airway disease was used to define the mechanism by which VEGF induces subepithelial fibrosis and to investigate a potential relationship between VEGF and TGF-beta(1) and the mechanisms by which VEGF signalling regulates TGF-beta(1) expression in allergic airway disease. The ovalbumin (OVA)-inhaled murine model revealed the following typical pathophysiological features of allergic airway disease in the lungs: increased numbers of inflammatory cells of the airways, airway hyperresponsiveness, increased peribronchial fibrosis, and increased levels of VEGF and TGF-beta(1). Administration of VEGF inhibitors reduced the pathophysiological signs of allergic airway disease and decreased the increased TGF-beta(1) levels and peribronchial fibrosis, including phosphoinositide 3-kinase (PI3K) activity after OVA inhalation. In addition, the increased TGF-beta(1) levels and collagen deposition after OVA inhalation were decreased by administration of PI3K inhibitors. These results suggest that inhibition of vascular endothelial growth factor attenuates peribronchial fibrosis, at least when mediated by regulation of transforming growth factor-beta(1) expression through phosphoinositide 3-kinase/Akt pathway in a murine model of allergic airway disease.

Pad - a new self-collection device for human papillomavirus

This study was designed to determine the accuracy and agreement of a self-collection method using pad for human papillomavirus (HPV) DNA. One hundred and thirty-four patients at university hospitals voluntarily participated in the accuracy study, and 314 volunteers participated in the agreement study at local clinics. DNA was extracted and amplified using HPV L1 consensus primers designed for the direct sequencing. In the accuracy study, all samples were probed via histological examinations. With regard to the detection of squamous intraepithelial lesion (SIL), self-collection pad sampling displays sensitivity, of 76.9%, and specificity, of 93.3%. Three hundred and fourteen self-collection pad samples and the concurrent physicians' samples showed a 97.8% agreement, with a Kappa value of 0.9200. A new self-collection pad for the detection of HPV DNA appears to constitute an easy, rapid, and convenient alternative method for the cervical cancer screening of many women with the virtue of being incredible readily accessible.

Development of hepatocellular carcinoma in patients with chronic hepatitis C who had a sustained virological response to interferon therapy: a multicenter, retrospective cohort study of 1124 patients

BACKGROUND

Interferon (IFN) improves hepatic inflammation/fibrosis and reduces the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C (CH-C). However, HCC develops in some patients who have a sustained virological response (SVR) to IFN therapy. We designed this study to establish a follow-up protocol for patients with CH-C who have SVR to IFN therapy.

METHODS

We retrospectively studied 1124 patients with CH-C who received IFN.

RESULTS

HCC developed in 3.5% of patients with SVR to IFN. As compared with SVR patients without HCC, SVR patients with HCC were predominantly male (P=0.003), older at the initiation of IFN therapy (P=0.002), and at a more advanced histologic stage of disease (P<0.001). However, three of the 13 SVR HCC patients had mild fibrosis. The mean interval from IFN therapy to the detection of HCC in SVR HCC patients was 5.8 years and did not differ significantly from that in non-SVR HCC patients (P=0.304). Although most patients with HCC received curative therapy, the prognosis of some SVR HCC patients was poor, probably because of insufficient follow-up, resulting in delayed detection of HCC.

CONCLUSIONS

SVR patients with CH-C who are elderly, male, or have an advanced histologic stage are at a high risk for the development of HCC after IFN therapy. We recommend that SVR patients should be observed carefully for more than 10 years after the completion of IFN therapy, even if they only have early fibrosis.

Four-dimensional ultrasound guidance of prenatal invasive procedures

OBJECTIVE

Technological advances in ultrasonography have revolutionized prenatal diagnosis and treatment. Here we evaluate the effectiveness of using four-dimensional (4D) ultrasonography to guide prenatal invasive procedures.

PATIENTS AND METHODS

Prenatal invasive procedures using 4D ultrasound were recorded prospectively in 93 cases: 10 amnioinfusions, 50 amniocenteses, 8 chorionic villus samplings (CVS) and 25 cordocenteses. The needle target site was first identified using the two-dimensional (2D) mode, and was then confirmed using the three-dimensional (3D) mode. The needle was inserted under 4D ultrasound guidance. After selecting the needle target site, the true position of the needle was determined in three planes ('real-time 3D targeting').

RESULTS

Using 4D ultrasound guidance, most procedures were performed within 5 min and with a 100% success rate, even in cases involving severe oligohydramnios (amniocentesis), thin placentas (CVS) or narrow umbilical veins (cordocentesis). Moreover, there were no serious complications during or after any procedure.

CONCLUSIONS

4D ultrasonography can be used to guide various prenatal invasive procedures offering clear information in all three planes. It is likely that such imaging will reduce the time taken to complete the procedures and reduce the risks associated with them. Published by John Wiley & Sons, Ltd.

Interferon-beta induction/interferon-alpha2b plus ribavirin therapy in patients with chronic hepatitis C

Treatment of chronic hepatitis C virus (HCV) infection with interferon (IFN) and ribavirin improves the rate of eradication of the virus by less than 20% in patients with genotype 1b and a high viral load. In this study we assessed whether IFN-beta induction/IFN-alpha2b plus ribavirin enhances the efficacy of the therapy in patients with chronic hepatitis C. The efficacy of IFN-beta induction/IFN-alpha2b plus ribavirin therapy (group A, n=7) was compared with that of IFN-alpha2b plus ribavirin (group B, n=7) in 14 patients with high levels of HCV-RNA (> 100 K/U/ml). No significant differences were observed in the clearance of HCV-RNA between the two groups (A and B, respectively) 2 weeks after the start of the treatment (0% and 14.3%), at the end of the treatment (71.4% and 100%) and 6 months after the end of the treatment (28.6% and 14.3%). Recovery was complete in 28.6% and 14.3%, transient in 42.9% and 85.7% and absent in 28.6% and 0% in groups A and B, respectively. Early log changes in the viral load from the baseline after 2 weeks of treatment were 2.41 +/- 0.91 and 2.77 +/- 0.20 in groups A and B, respectively, with no significant difference between the two groups. In the present study, we were not able to demonstrate that IFN-beta induction/IFN-alpha2b plus ribavirin therapy was superior to IFN-alpha2b plus ribavirin therapy in patients with genotype 1b and high viral loads.

Emotion recognition system using short-term monitoring of physiological signals

A physiological signal-based emotion recognition system is reported. The system was developed to operate as a user-independent system, based on physiological signal databases obtained from multiple subjects. The input signals were electrocardiogram, skin temperature variation and electrodermal activity, all of which were acquired without much discomfort from the body surface, and can reflect the influence of emotion on the autonomic nervous system. The system consisted of preprocessing, feature extraction and pattern classification stages. Preprocessing and feature extraction methods were devised so that emotion-specific characteristics could be extracted from short-segment signals. Although the features were carefully extracted, their distribution formed a classification problem, with large overlap among clusters and large variance within clusters. A support vector machine was adopted as a pattern classifier to resolve this difficulty. Correct-classification ratios for 50 subjects were 78.4% and 61.8%, for the recognition of three and four categories, respectively.

Pathologic characteristics of prostatic adenocarcinomas: a mapping analysis of Korean patients

Pathologic characteristics of the prostatic adenocarcinoma in Koreans are not clear. We studied 132 cases of prostatectomy specimens using mapping analysis to discover the pathologic characteristics of the Korean prostatic adenocarcinoma. Mean values were as follows: serum prostate-specific antigen level (sPSA), 16.4 ng/ml; tumor volume, 27.5%; size, 2.4 cm; Gleason score, 7.7; and p53 expression, 9.8%. Rates of multifocal tumors and high-grade prostatic intraepithelial neoplasm (HPIN) were 33.3 and 65.2%. The Gleason score, tumor volume%, tumor size and sPSA were correlated with each other. Korean prostatic adenocarcinomas showed higher Gleason scores, lower rates of HPIN and multifocality, and lower p53 expression in comparison to Western prostatic adenocarcinomas. These data may be a basis for pathologic characteristics of Korean prostatic adenocarcinoma that has now been increasing.

The effect of divalent metal ions on the zeta potential of bubbles

Micro-bubbles are used in electro-flotation (EF) and dissolved air flotation (DAF) for particle separation. The efficiency of these flotation processes depends on the collision of bubble and particle and the collision efficiency is affected by certain parameters with respect to the size and zeta potential of bubble and particle. Therefore, it is necessary to monitor not only the zeta potential of the particle, but also that of the bubble. Gas bubbles are reported to be generally negatively charged in water. In this paper, we report a study performed to measure the zeta potential of bubbles in solutions containing divalent metals and find factors which can produce positively charged bubbles. Calcium and magnesium ions were selected as divalent metal ions because natural water normally contains an appreciable quantity of them. It was found that bubbles are negatively charged in CaCl2 solutions whereas, under certain conditions, they become positively charged in MgCl2. Charge reversal of bubbles was observed above 10(-2) M Mg, especially above pH 9. A probable principle that explained the charge reversal could be a combined mechanism with both specific adsorption of hydroxylated species and formation of hydroxide precipitates. Creating solution conditions that can produce positively charged bubbles in flotation methods might make it possible to remove particles using lesser amounts of coagulant or even none at all.

Synthesis of Si, Mg substituted hydroxyapatites and their sintering behaviors

Si, Mg-substituted hydroxyapatites, alone and co-substituted, have been prepared to obtain biomaterials having an improved biocompatibility. From FT-IR, XRD and ICP analyses, it was confirmed that single phases of hydroxyapatite substituted by Si alone or co-substituted by Si, Mg. The XRD data indicated the absence of extra phases related to silicon and magnesium oxide or other calcium phosphate species. Si-substituted hydroxyapatite of up to 2 wt% for Si and Si, Mg co-substituted hydroxyapatite of 1 wt% for the each ion keep their original structures intact for the sintering temperatures of up to 1200 degrees C. However, it is observed that ion substitutions by an amount higher than the above ratios for each hydroxyapatite lead to destabilization of original structures of the hydroxyapatite and to the production of tricalcium phosphate and calcium phosphate silicate phases when the samples were sintered at 1100 degrees C or higher.

Assessment of the disturbances in metabolic homeostasis: a hypothesis of synergism

Based on the hypothesis that a synergistic interaction between triiodothyronine (T(3)) and insulin contributes to abnormalities in glucose and other metabolic pathways, the mechanisms underlying the impairment of metabolic homeostasis (MH) and the development of type-2 diabetes (DM) were investigated via a proposed homeostatic model, [(FG*TG)/T3*FI)]. The MH model characterizes the relationship between T(3) and insulin and the levels of triglycerides (TG), fasting insulin (FI), and fasting glucose (FG) and is introduced as a clinical method to assess insulin sensitivity and the status of metabolic homeostasis in lieu of current screening models advocated by the by American Diabetic Association (ADA). The present study validated the hypothetical model in a sample of 110 African-American women.

A hypothesis of synergism: the interrelationship of T3 and insulin to disturbances in metabolic homeostasis

While the role of abnormal insulin homeostasis in the pathogenesis of Type-2 diabetes mellitus is well established, the importance of the canonical role of T(3) on Type-2 diabetes or the homeostasis of glucose, lipid, and energy balance has not been addressed. Based on the available evidence from molecular biology, the pivotal regulatory role of T(3) in major metabolic pathways and glycemic control can be delineated by mapping the specific action sites of T(3) and insulin on the metabolic pathways of the glucose-lipid cycle. The current paper presents an integrative hypothesis of the synergistic relationship of T(3) and insulin in metabolic homeostasis and abnormalities.

Histological study of PIVKA-II expression in hepatocellular carcinoma and adenomatous hyperplasia

Although serum concentration of protein induced vitamin K absence or antagonist II (PIVKA-II) has been widely used for diagnosing hepatocellular carcinoma (HCC), little information is available concerning tissue PIVKA-II as an immunohistochemical marker for liver histology. In this study, we examined the expression of PIVKA-II in precancerous nodules (adenomatous hyperplasia) and various differentiation grades of HCC by immunohistochemical study using the monoclonal anti-PIVKA-II antibody (MU-3). We examined the relationship between tissue PIVKA-II staining and serum PIVKA-II level, tumor histology and tumor size. PIVKA-II was mainly detected in the cytoplasm of the HCC cells. The positive rates of PIVKA-II were as follows: adenomatous hyperplasia (AH), 0% (0/9); well-differentiated HCC, 65% (15/23); moderately differentiated HCC, 85% (22/26); poorly differentiated HCC, 54% (7/13). The expression of tissue PIVKA-II staining in moderately differentiated HCC was significantly higher than in well- or poorly differentiated HCC, whereas the serum PIVKA-II level in poorly differentiated HCC was higher than well- or moderately differentiated HCC. There was no relationship between the expression of PIVKA-II in cancer tissues and serum levels of PIVKA-II. Immunohistochemical studies revealed that PIVKA-II was expressed even in small-sized or well-differentiated HCC cells, but expression was not detected in AH. It was concluded that PIVKA-II is a useful immunohistochemical marker, even in small-sized or well-differentiated HCC.

Preoperative uterine artery embolization and evacuation in the management of cervical pregnancy: report of two cases

Preoperative uterine artery embolization and cervical evacuation as conservative management of cervical pregnancy has been tried in recent years. However, cervical suturing, vasoconstrictor injection, or cervical ballooning was frequently used as an ancillary measures in those procedures in most of the previous studies. We report two cases of cervical pregnancy that were successfully treated with preoperative uterine artery embolization and removal of gestational material without ancillary procedures. Our therapeutic modality seems to be safe and effective for conservative management of cervical pregnancy.

N-terminal processing is essential for release of epithin, a mouse type II membrane serine protease

Epithin was originally identified as a mouse type II membrane serine protease. Its human orthologue membrane type-serine protease 1 (MT-SP1)/matriptase has been reported to be localized on the plasma membrane. In addition, soluble forms of matriptase were isolated from human breast milk and breast cancer cell-conditioned medium. In this paper, we report a processing mechanism that appears to be required for the release of epithin. CHO-K1 or COS7 cells transfected with single full-length epithin cDNA generated two different-sized proteins in cell lysates, 110 and 92 kDa. The 92-kDa epithin was found to be an N-terminally truncated form of the 110-kDa epithin, and it was the only form detected in the culture medium. The 92-kDa epithin was also found on the cell surface, where it was anchored by the N-terminal fragment. The results of in vivo cell labeling experiments indicate that the 110-kDa epithin is rapidly processed to the 92-kDa epithin. Using site-directed mutagenesis experiments, we identified Gly(149) of the GSVIA sequence in epithin as required for the processing and release of the protein. These results suggest that N-terminal processing of epithin at Gly(149) is a necessary prerequisite step for release of the protein.

Constitutive expression of rice MADS box gene using seed explants in hot pepper (Capsicum annuum L.)

Two transgenic pepper plants were obtained from 255 seed explants that were infected with Agrobacterium LBA4404 (pGA1209). One of them (PT2) showed morphological change, such as dwarfism and early flowering by the constitutive expression of the rice OsMADS1 gene. The in vitro condition of the plant regeneration has been optimized from hypocotyl explants on a MS medium that was supplemented with zeatin 3 mg/L, IAA 0.3 mg/L for shoot induction. The optimal rooting condition was at NAA 0.3 mg/L. The transformation frequency was 0.8% from the total hypocotyls. DNA and RNA hybridization analyses showed that the introduced gene was integrated and stably expressed in regenerated plants.

Roles of chromosomal and episomal dinB genes encoding DNA pol IV in targeted and untargeted mutagenesis in Escherichia coli

DNA polymerase IV (pol IV) in Escherichia coli is a member of a novel family of DNA polymerases (the DinB/UmuC/Rad30/Rev1 super-family or the DNA polymerase Y family). Although expression of the dinB gene encoding DNA pol IV is known to result in an enhancement of untargeted mutagenesis, it remains uncertain whether DNA pol IV is involved in a variety of lesion-induced mutagenesis (targeted mutagenesis), and the relationship between expression levels of dinB and the mutagenesis that DNA pol IV promotes has not been investigated thoroughly. Here, we report that DNA pol IV is involved in -1 frameshift mutagenesis induced by 4-nitroquinoline N-oxide (4-NQO) and that the expression level of the chromosomal pol IV gene is 6-12 times higher than those for other SOS-inducible DNA polymerases in E. coli, i.e., DNA pol II (PolB) or DNA pol V (UmuDC), respectively. Interestingly, the dinB gene is present not only on the chromosome but also on the F' plasmid in the E. coli CC108 strain. In this strain, 750 molecules of DNA pol IV are expressed from the F' dinB gene in the uninduced state and 250 molecules are expressed from the chromosomal gene. These cellular expression levels strongly affect -1 frameshifts induced by 4-NQO in runs of six guanine bases: mutagenicity was highest in the strain CC108, followed by strains YG2242 (chromosome deltadinB/F' dinB+), YG2247 (chromosome dinB+/F' deltadinB) and FC1243 (chromosome deltadinB/F' deltadinB). The incidence of untargeted -1 frameshifts was reduced by two-thirds on deletion of dinB from the F' episome. The chromosomal dinB gene appeared to have little or no effect on the untargeted mutagenesis. These results suggest that DNA pol IV efficiently mediates targeted mutagenesis by 4-NQO, and that the cellular levels of expression substantially affect targeted and untargeted mutagenesis.