Structure-based hybridization, synthesis and biological evaluation of novel tetracyclic heterocyclic azathioxanthone analogues as potential antitumor agents

A series of tetracyclic heterocyclic azathioxanthones were synthesized and evaluated for cell proliferations, topoisomerase inhibitions, and NCI-60 cell panel assay, respectively. Compounds 5, 7, 8, 16, and 19 were selected for topoisomerase assay after MTT assay. 7 not only showed cytotoxic effect (IC50 = 2.84 ± 0.64 μM) in PC-3 cells but also revealed topoisomerases inhibition with IC50 (10-25 μM) and increased apoptotic cleavage of PARP and caspase 3 activity. The overall of novel azathioxanthones with different cytostatic and cytotoxic activities should be further developed as new potential candidates for anticancer drugs.

Cumulative risk assessment for plasticizer-contaminated food using the hazard index approach

Phthalates strongly and adversely affect reproduction, development and liver function. We did a cumulative risk assessment for simultaneous exposure to nine phthalates using the hazard index (HI) and the levels of nine phthalates in 1200 foodstuff samples. DEHP (di-2-ethylhexyl phthalate) present the highest level (mean: 0.443 mg/kg) in 1200 samples, and the highest average daily dose (ADD) was found in DEHP, ΣDBP(i + n) (the sum of dibutyl phthalate [DBP] isomers [DnBP + DiBP]) posed the highest risk potential of all the phthalates. In seven phthalates, the 95th percentiles of the ADDs for ΣDBP(i + n) in 0-6-yr-old children accounted for 91% (79-107%) of the tolerable daily intake, and the 95th percentiles of the HIs for the anti-androgenic effects of five phthalates in 0-3-yr-old children and 4-6-yr-old girls were >1. We conclude that the health of younger Taiwanese may be adversely affected by overexposure of phthalate-contaminated foods.

Clinical association of circulating VEGF-B levels with hyperlipidemia and target organ damage in type 2 diabetic patients

Vascular endothelial growth factor-B (VEGF-B is an important member of the VEGF protein family. Recent animal studies indicated that VEGF-B signaling had determinant roles in insulin resistance, lipid distribution and metabolism in type 2 diabetes. The clinical significance of VEGF-B in type 2 diabetes is still not clear. This study aimed to correlate VEGF-B levels with biochemistry characteristics and target organ damage in type 2 diabetic patients. Serum VEGF-B levels were measured using ELISA. A crosssectional control study, which included 180 type 2 diabetic patients and 62 healthy subjects, was carried out. Diabetic patients who were undergoing insulin therapy were not included. This results showed that serum VEGF-B levels did not differ between the type 2 diabetic patients and the healthy controls (169.2∓118.8 vs 163.5∓115.2 pg/mL; P=0.734). VEGF-B levels in type 2 diabetic patients were significantly associated with the levels of c-peptide, total cholesterol and triglyceride. T-test analysis showed that the associations of serum VEGF-B levels with insulin resistance, pancreatic reserve, HDL and LDL were not significant. Regression analysis showed that VEGF-B levels were significantly correlated with diabetic retinopathy and nephropathy. No significant association between VEGF-B and macro-vasculopathy was found. In conclusion, our study findings suggested that VEGF-B levels did not differ between the type 2 diabetic patients and the normal controls. High VEGF-B levels might correlate with the presence of hyperlipidemia and target organ damage in type 2 diabetic patients.

Comparison of NMOSFET and PMOSFET devices that combine CESL stressor and SiGe channel

Strained-Si technology could enhance the carrier mobility and improve the device performance. Contact-etch-stop-layer (CESL) structure with different stress and SiGe channel was fabricated with 90-nm technology. The electrical properties of N and PMOSFET devices combining CESL and SiGe channel were investigated. The short channel effects (SCE), such as drain-induced barrier lowering (DIBL), were also studied. Moreover, the stress contour in the SiGe channel has been simulated with TCAD to understand the relationship between stress distribution and device performance for different CESL structures. It is observed that the stress in the channel region was independent of the type of N or PMOSFET devices, but it was dependent on the CESL type and channel length. Based on the experimental and simulation results, it is confirmed that the device performance is associated with the stress in the channel, and the approach of CESL stressor and SiGe channel is shown to effectively improve the mobility of NMOSFETs and PMOSFETs.

Design, synthesis and antiproliferative evaluation of fluorenone analogs with DNA topoisomerase I inhibitory properties

A series of 2,7-diamidofluorenones were designed, synthesized, and screened by SRB assay. Some synthesized compounds exhibited antitumor activities in submicromolar range. Ten compounds (3a, 3b, 3c, 3g, 3j, 3l, 4a, 4h, 4i, and 4j) were also selected by NCI screening system and 3c (GI50=1.66 μM) appeared to be the most active agent of this series. Furthermore, 3c attenuated topoisomerase I-mediated DNA relaxation at low micromolar concentrations. These results indicated that fluorenones have potential to be further developed into anticancer drugs.

Correction of Wassel type IV thumb duplication with zigzag deformity: results of a new method of flexor pollicis longus tendon relocation

The purpose of this study is to present a treatment algorithm and a method of flexor pollicis longus tendon relocation for Wassel type IV thumb duplication with zigzag deformity. Forty-two thumbs in 42 patients were included in this study and the mean follow-up was 4 years. In addition to excision of the extra digit, tendon relocation and metacarpal and/or proximal phalangeal osteotomy were carried out, based on the degree of angulation at the metacarpophalangeal and interphalangeal joints. Tendon relocation was achieved using our pull-out suture technique. The results were assessed using an evaluation form for thumb polydactyly provided by the Japanese Society for Surgery of the Hand. At the time of latest clinical contact, eight cases were rated good, 31 cases fair, and three cases poor. It is useful to decide surgical procedures according to the degree of angulation of the metacarpophalangeal and interphalangeal joints and flexor pollicis longus tendon relocation is important to prevent malalignment at the interphalangeal joint.

New approaches of PARP-1 inhibitors in human lung cancer cells and cancer stem-like cells by some selected anthraquinone-derived small molecules

Poly (ADP-ribose) polymerase-1 (PARP-1) and telomerase, as well as DNA damage response pathways are targets for anticancer drug development, and specific inhibitors are currently under clinical investigation. The purpose of this work is to evaluate anticancer activities of anthraquinone-derived tricyclic and tetracyclic small molecules and their structure-activity relationships with PARP-1 inhibition in non-small cell lung cancer (NSCLC) and NSCLC-overexpressing Oct4 and Nanog clone, which show high-expression of PARP-1 and more resistance to anticancer drug. We applied our library selected compounds to NCI's 60 human cancer cell-lines (NCI-60) in order to generate systematic profiling data. Based on our analysis, it is hypothesized that these drugs might be, directly and indirectly, target components to induce mitochondrial permeability transition and the release of pro-apoptotic factors as potential anti-NSCLC or PARP inhibitor candidates. Altogether, the most active NSC747854 showed its cytotoxicity and dose-dependent PARP inhibitory manner, thus it emerges as a promising structure for anti-cancer therapy with no significant negative influence on normal cells. Our studies present evidence that telomere maintenance should be taken into consideration in efforts not only to overcome drug resistance, but also to optimize the use of telomere-based therapeutics. These findings will be of great value to facilitate structure-based design of selective PARP inhibitors, in general, and telomerase inhibitors, in particular. Together, the data presented here expand our insight into the PARP inhibitors and support the resource-demanding lead optimization of structurally related small molecules for human cancer therapy.

Development of a wearable system integrated with novel biomedical sensors for ubiquitous healthcare

The world's ageing population has led to an urgent need for long-term and patient-centered healthcare solutions. Hence, there is a growing need for wearable systems for physiologic monitoring. While various biosignals are monitored with traditional approaches, it is worthwhile to investigate alternative sensing techniques in order to improve accessibility and understanding of patients' conditions. This paper presents our laboratory's development of such a wearable system, which makes use of unconventional techniques for physiologic monitoring. With its integrated textile electrocardiogram (ECG) electrodes, intelligent finger-ring photoplethysmogram (PPG) sensor, miniaturized optical fiber-based temperature sensor, eye dynamics monitor, global positioning system (GPS) module, and wireless capability, it demonstrates a feasible solution for ubiquitous healthcare.

Cathelicidin protects against Helicobacter pylori colonization and the associated gastritis in mice

Cathelicidin, an antimicrobial peptide of the innate immune system, has been shown to modulate microbial growth, wound healing and inflammation. However, whether cathelicidin controls Helicobacter pylori infection in vivo remains unexplored. This study sought to elucidate the role of endogenous and exogenous mouse cathelicidin (CRAMP) in the protection against H. pylori infection and the associated gastritis in mice. Results showed that genetic ablation of CRAMP in mice significantly increased the susceptibility of H. pylori colonization and the associated gastritis as compared with the wild-type control. Furthermore, replenishment with exogenous CRAMP, delivered via a bioengineered CRAMP-secreting strain of Lactococcus lactis, reduced H. pylori density in the stomach as well as the associated inflammatory cell infiltration and cytokine production. Collectively, these findings indicate that cathelicidin protects against H. pylori infection and its associated gastritis in vivo. Our study also demonstrates the feasibility of using the transformed food-grade bacteria to deliver cathelicidin, which may have potential clinical applications in the treatment of H. pylori infection in humans.

Robust radial basis function neural networks

Function approximation has been found in many applications. The radial basis function (RBF) network is one approach which has shown a great promise in this sort of problems because of its faster learning capacity. A traditional RBF network takes Gaussian functions as its basis functions and adopts the least-squares criterion as the objective function, However, it still suffers from two major problems. First, it is difficult to use Gaussian functions to approximate constant values. If a function has nearly constant values in some intervals, the RBF network will be found inefficient in approximating these values. Second, when the training patterns incur a large error, the network will interpolate these training patterns incorrectly. In order to cope with these problems, an RBF network is proposed in this paper which is based on sequences of sigmoidal functions and a robust objective function. The former replaces the Gaussian functions as the basis function of the network so that constant-valued functions can be approximated accurately by an RBF network, while the latter is used to restrain the influence of large errors. Compared with traditional RBF networks, the proposed network demonstrates the following advantages: (1) better capability of approximation to underlying functions; (2) faster learning speed; (3) better size of network; (4) high robustness to outliers.

Site occupancy and magnetic properties of pyrochlore-structured AgOs2O6

AgOs(2)O(6) prepared from ion-exchanged superconducting β-pyrochlore KOs(2)O(6) has been shown to be non-superconducting. Synchrotron x-ray structure refinement suggests that AgOs(2)O(6) has the Ag ion mostly occupying the low-symmetry 32e site in the [Formula: see text] space group of proper occupancy, which is different from the original major occupancy at the high-symmetry 8b site for KOs(2)O(6), and similar to non-superconducting Na(1.4)Os(2)O(6)·H(2)O. Magnetic susceptibility measurements found no magnetic ordering down to ~1.7 K. The trace amount of isolated spins suggests that the Ag could be neutral and lead to a pure Os(6+) valence state of zero spin in the newly prepared AgOs(2)O(6).

Biochemical study of retired pentachlorophenol workers with and without following dietary exposure to PCDD/Fs

PCDD/Fs are found as impurities in commercial pesticide sodium pentachlorophenol (Na-PCP) salt. We compared, using multivariate logistic regression analysis adjusted for confounding factors, serum PCDD/F levels and biochemical examinations of retired Na-PCP workers and other inhabitants living near a closed Na-PCP plant that discharged PCP-contaminated wastewater into a nearby pond in Tainan, Taiwan. In this cross-sectional study from October 2006 through May 2009, 1167 participants were divided into groups according to their occupational (retired Na-PCP plant workers versus other residents) and dietary exposure (eating polluted fish versus not eating polluted fish) to PCDD/Fs, and a general population from a large-scale survey. Serum PCDD/F levels were significantly different between these groups (range: from 22.9±10.0pg WHO(98)-TEQ(DF) g(-1) lipid in the general population to 109.6±94.5pg WHO(98)-TEQ(DF) g(-1) lipid in retired Na-PCP workers eating polluted seafood; P(trend)<0.001). Distinct patterns of PCDD/Fs congener profiles, showing a significantly higher proportion of 1,2,3,7,8-PeCDD, 1,2,3,6,7,8-HxDD, and less 2,3,4,6,7,8-HpCDF, OCDF, were also found among workers and residents with different serum PCDD/F levels versus the general population. After adjusting for confounding factors, glucose (adjusted odds ratio [AOR] 7.22 [95% CI: 4.04-12.90]), triglycerides (AOR 4.31 [95% CI: 2.57-7.22]), blood urea nitrogen (AOR 2.90 [95% CI: 1.58-5.33]), creatine (AOR 5.83 [95% CI: 1.12-30.30]) and total protein (AOR 3.74 [95% CI: 1.91-7.31]) levels in retired workers were significantly higher than in the reference group. Occupational exposure to PCDD/Fs is associated with biochemical abnormalities that may persist for years after serum PCDD/F levels have declined.

Association analysis of dopaminergic gene variants (Comt, Drd4 And Dat1) with Alzheimer s disease

Defects in dopaminergic transmission play important roles in the disturbance of synaptic plasticity and even in advanced cognitive behavior. However, the relationship between genes involved in the regulation of dopamine levels and predisposition for Alzheimer s disease (AD) remains unclear. The potential association of dopamine-modulating gene polymorphisms with AD was evaluated. We performed a case-control study with 120 patients and 86 healthy controls. Two catechol-O-methyltransferase (COMT) single-nucleotide polymorphisms (SNPs) (rs2020917 and rs4646312), two dopamine D4 receptor (DRD4) SNPs (rs3758653 and rs916455), and four dopamine transporter (DAT1) SNPs (rs2937639, rs6347, rs12516948 and rs11133762) were investigated. The T allele at the DRD4 SNP (rs3758653) was found to be significantly associated with AD. Our results also showed that haplotype frequencies, observed from the analyzed SNPs, were distributed significantly differently in AD patients vs control subjects. Moreover, a strong association was observed between the A allele at rs6347 of DAT1 and moderate stage of dementia. These observations suggest that genetic variations in the dopamine-modulating genes, COMT, DRD4 and DAT1, may contribute to AD pathogenesis in the Taiwanese population.

Frequent detection of plasmid-mediated quinolone resistance (qnr) genes in multidrug-resistant Enterobacteriaceae blood isolates, Hong Kong

Plasmid-mediated quinolone resistance (qnr) genes confer low-level resistance but provide background for selection of highly-resistant strains. We investigated their prevalence and significance in clinical Enterobacteriaceae bacteremic isolates in Hong Kong. A prospective, hospital-based study was conducted (January 2008 to March 2009). Consecutive, non-duplicate blood isolates of extended-spectrum-β-lactamase (ESBL) and/or plasmid-mediated AmpC (PMAmpC) β-lactamase-producing Enterobacteriaceae were collected and subjected to qnr genes detection using multiplex PCR. Direct sequencing was performed to characterize the qnr and the co-existing bla genes. Clinical and microbiological variables, including antimicrobial resistance profiles, were compared between infections by 'qnr-positive' and 'qnr-negative' Enterobacteriaceae. Altogether 199 ESBL/PMAmpC-producing Enterobacteriaceae isolates were studied. qnr genes were detected in 20 % (qnrB, n = 24; qnrS, n = 16; qnrA, n = 0), of which 85% were Klebsiella spp. There was a strong association with PMAmpC genes (qnrB and DHA-1; p < 0.001). 'qnr-positive' isolates were more commonly hospital-acquired (60.0% vs 35.8%; adjusted OR 2.68, 95%CI 1.32-5.46) and multidrug-resistant (e.g. amoxicillin-clavulanate 90-100%, piperacillin-tazobactam 40-57%, ceftazidime 53-78%; sulfamethoxazole/trimethoprim 60-70%; ciprofloxacin 53-65%, levofloxacin 35-48%). Patients with 'qnr-positive' Enterobacteriaceae bacteremia had a higher 30-day mortality (45% vs 22%, p = 0.003). High Pitt bacteremia score, development of pneumonia, and failure to receive susceptible fluoroquinolone (adjusted HR 4.27; 95%CI 1.45-12.61) or carbapenem (adjusted HR 3.04; 95%CI 1.49-6.20) treatment were independent factors associated with death. A high proportion of ESBL/PMAmpC-producing Enterobacteriaceae (typically Klebsiella) bacteremic isolates carried qnr. These strains were multidrug-resistant, which was associated with inappropriate treatment and high fatality. Further dissemination of qnr and selection of fluoroquinolone/β-lactam-resistant strains should be closely monitored and controlled.

Effect of oral phytoestrogen on androgenicity and insulin sensitivity in postmenopausal women

AIM

The aim of this study was to determine and compare the effect of treatment with transdermal oestrogen and phytoestrogen on insulin sensitivity and sex hormone-binding globulin (SHBG) levels in healthy postmenopausal women.

METHODS

Forty-three healthy postmenopausal women aged 68 ± 7 (mean ± SD) years who were not receiving hormonal replacement therapy completed a 3 month randomized drug therapy study. The participants were randomized to one of four groups: 0.05 mg or 0.1 mg transdermal oestrogen/day, or 40 or 80 mg oral phytoestrogen (Promensil)/day insulin sensitivity was indirectly measured using the quantitative insulin sensitivity check index (QUICKI). SHBG, total testosterone, oestradiol, and fasting glucose and insulin levels for calculation of insulin sensitivity were obtained at baseline and at monthly intervals during the 3 months of therapy.

RESULTS

In healthy nondiabetic postmenopausal women, the rate of change in QUICKI was significantly different between the red clover based phytoestrogen and transdermal oestrogen groups, so that after three months of therapy, QUICKI with red clover based phytoestrogen therapy was lower than that in the transdermal oestrogen group, p = 0.01. Red clover based phytoestrogen therapy was not associated with any changes in SHBG levels whereas transdermal estrogen therapy significantly increased SHBG levels, p = 0.05.

CONCLUSIONS

In contrast to transdermal oestrogen therapy, oral phytoestrogen therapy does not decrease androgenicity and is associated with a decrease in insulin sensitivity. These effects are similar to those of raloxifene and consistent with phytoestrogen's selective oestrogen receptor modulator properties.

Acute HIV infection in Singapore: predominance of men who have sex with men

INTRODUCTION

The incidence of human immunodeficiency virus (HIV) infection in Singapore is on the rise. We aimed to study the clinical epidemiology of acute HIV infection in Singapore.

METHODS

All patients that fulfilled the criteria for definite and probable acute HIV infection were prospectively identified from January 1, 2003 to June 30, 2006. Demographic, clinical and laboratory data were recorded.

RESULTS

A total of 16 out of 34 patients had definite acute HIV infection, and 68 percent of the entire cohort comprised men who have sex with men (MSM). Ten percent of the patients were co-infected with hepatitis B and C viruses, while 27 percent were infected with syphilis. Signs and symptoms were nonspecific, with fever, rash and diarrhoea being the three most common symptoms. Only 35 percent of the patients required hospitalisation.

CONCLUSION

Men who have sex with men account for the majority of patients with acute HIV infections in Singapore, many of them also being co-infected with syphilis. Safer sex campaign among MSM should be implemented or intensified.

Analysis and modeling of nano-crystalline silicon TFTs on flexible substrate with mechanical strain

The gap state density of nano-crystalline silicon active layers on a flexible substrate was redistributed with mechanical bending. The weak or broken bonds may contribute to the redistribution of trap states. During mechanical strain, the deep states redistributed in a Gaussian distribution, and are dissimilar to ordinary acceptor-like deep states, which manifest with exponential distributions. We conclude that the gap state density with TCAD modeling under mechanical strain is the fundamental reliability issue for the development of flexible electronics.

Cellular dosimetry and microdosimetry for internal electron emitters

Radiobiological descriptions of cellular dosimetry and microdosimetry require both radiation dose and radiation quality. The lineal energy, defined as a ratio of the energy deposition by a particle in the biological target and the mean chord length of this target, is generally adopted to characterise the radiation quality. Most microdosimetry applications assume that the cell nucleus is the target region. Therefore, the lineal energy is obtained for the source (S) to target (T) geometry, T ← S, where S = cell surface, cytoplasm, cell nucleus and T = cell nucleus. The definition of lineal energy is based on the approximation that the particle mean pathlength is equal to target mean chord length. This approximation is valid for crossers of external irradiations. In the case of starters, insiders and stoppers of internal sources, particle pathlengths are always shorter than target chord lengths. Thus, the lineal energy does not reflect the specific energy deposition along particle path. In the present work, the specific energy deposition in a target is calculated using three distance parameters, i.e. target mean chord length, particle mean pathlength in the target and particle individual pathlength in the target. Monte Carlo calculations are performed for electrons of various energies and cells of different sizes. Results are analysed and discussed.

Optimal design of a microcavity organic laser device under electrical pumping

The quality factor of microcavity organic lasers, designed for operation under electric pumping, has been numerically investigated. The microcavity structure consists of an organic light emitting diode set in between multilayer dielectric mirrors centered for an emission at 620 nm. In order to optimize the quality factor, different parameters have been studied: the impact of high and low index materials used for the multilayer mirrors, the role of a spacer inserted in between the mirrors to obtain an extended cavity, and the effect of an absorbing electrode made of metallic or transparent conductive oxide layer. The results of our different optimizations have shown a quality factor (Q) as high as 15,000.

Mosaic supernumerary r(1)(p13.2q23.3) in a 10-year-old girl with epilepsy facial asymmetry psychomotor retardation kyphoscoliosis dermatofibrosarcoma and multiple exostoses

We report molecular cytogenetic characterization of mosaic supernumerary r(1)(p13.2q23.3) in a 10-year-old girl with epilepsy, facial asymmetry, psychomotor retardation, kyphoscoliosis, dermatofibrosarcoma and multiple exostoses. The supernumerary r(1) is associated with gene dosage increase of CHRNB2, ADAR and KCNJ10 in the pericentromeric area of 1q, and a breakpoint within CTTNBP2NL at 1p13.2. We speculate that the gene dosage increase of CHRNB2, ADAR and KCNJ10 is most likely responsible for epilepsy, and the breakpoint at 1p13.2 in the supernumerary r(1) is most likely responsible for the development of multiple exostoses and osteochondroma in this patient.

Interrelationship between exposure to PCDD/Fs and hypertension in metabolic syndrome in Taiwanese living near a highly contaminated area

Metabolic syndrome (MetS) consists of a constellation of metabolic abnormalities that confer increased risk of cardiovascular disease. There is a positive correlation between exposure to persistent organic pollutants and MetS. We examine the association between PCDD/Fs and MetS components in 1490 non-diabetic persons living near a highly dioxin-contaminated area. We used factor analysis, with a set of core variables considered central features of MetS and PCDD/Fs, to group similar risk factors. Serum PCDD/Fs were positively and significantly correlated with the number of MetS components. Four risk factors-lipidemia, blood pressure, body size, and glycemia-accounted for 72.6% of the variance in the 10 core factors, and PCDD/Fs were linked to MetS through shared correlations with high blood pressure. After adjusting for confounding factors, we found that diastolic blood pressure (β=0.018; p=0.006), glucose (β=0.013; p=0.046), and waist circumference (β=0.721; p=0.042) significantly increased with increasing serum PCDD/F levels. We found significant trends for associations between metabolic syndrome and serum low-chlorinated PCDD/Fs. The highest quintiles of 2,3,4,7,8-PeCDF, 1,2,3,6,7,8-HxCDF and 2,3,7,8-TCDD had the top three adjusted ORs (95% CI) of 3.5 (1.9-6.3), 2.9 (1.7-4.9) and 2.8 (1.6-4.9), respectively. We also found a slight monotonic relationship between serum PCDD/Fs and the prevalence of MetS, especially when the serum dioxin level was higher than 25.4pg WHO(98)-TEQ(DF)g(-1) lipid (the fourth Quintile). We hypothesize that high-dose exposure to PCDD/Fs is a blood pressure-related factor that raises MetS risk.

Association between alcohol consumption and diabetic retinopathy and visual acuity-the AdRem Study

AIMS

We investigated the association between alcohol consumption and diabetic retinopathy and deterioration of visual acuity in individuals with Type 2 diabetes.

METHODS

We conducted a cohort analysis of 1239 participants with Type 2 diabetes aged 55-81 years enrolled in the AdRem study, a sub-study of the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) trial. Current and past consumption of wine, spirits and beer was measured by self-report. Moderate and heavy alcohol consumption was defined as 1-14 and >14 drinks/week, respectively. Diabetic retinopathy, measured by mydriatic stereoscopic seven-field retinal photography, was defined by a 2-step progression in the Early Treatment of Diabetic Retinopathy Study (ETDRS) score or the presence of any retinal vascular lesions. Deterioration of visual acuity was defined by a decrease of two lines in best vision in either eye, measured corrected, or through a pinhole using a Snellen chart.

RESULTS

In a mean follow-up of 5.5 years, we identified 182 participants with a 2-step progression in the ETDRS score, 640 participants with the presence of any retinal vascular lesions and 693 participants with a deterioration of visual acuity. Current moderate consumption of alcohol, compared with no current consumption, was not associated with presence or progression of diabetic retinopathy; however, it was associated with higher risk of deterioration of visual acuity (multivariable-adjusted OR 1.83; 95% CI 1.34-2.48; P<0.001).

CONCLUSIONS

Alcohol consumption is associated with increased risk of deterioration of visual acuity, but not with retinopathy in individuals with Type 2 diabetes.

Prevalence and characteristics of ertapenem-nonsusceptible Escherichia coli in a Taiwanese university hospital, 1999 to 2007

The present study was conducted to investigate the prevalence and characteristics of ertapenem-nonsusceptible (ETP-NS) Escherichia coli in a Taiwanese university. A total of 9,722 isolates collected in 1999, 2003, 2005, and 2007 were examined. Overall, 1.0% of all isolates from 66 patients were interpreted as ETP-NS on the basis of the disk diffusion test result. Most of these isolates were clonally unrelated and showed low-level ertapenem resistance, the production of CMY-2 cephalosporinase (86.4%), and decreased expression of the OmpF (97.0%) and/or OmpC (56.1%) porins. No carbapenemase was detected. The decreased porin expression was associated with disruptions of ompF or ompC in only about one-third of the ETP-NS isolates. During the study period, the prevalence of ETP-NS strains increased from 0.1 to 1.7%, accompanying an increase (0.8 to 17.6%) in the prevalence of CMY-2 producers. Coexistent or pre-existing clonally related ertapenem-susceptible (ETP-S) E. coli isolates were identified in 47.0% of all case patients, and almost all of the ETP-S isolates had the same β-lactamases as the ETP-NS isolates. Our study results suggest the restricted use of extended-spectrum cephalosporins to hinder the emergence and prevalence of carbapenem resistance in E. coli, which may arise by the accumulation of multiple resistance determinants.

Adenosine Triphosphate Content of Selenastrum capricornutum

The adenosine triphosphate content of Selenastrum capricornutum was maintained within 1.4 to 3.4 mug of adenosine triphosphate/mg (dry weight) of living biomass at different growth stages in media of different phosphorus concentrations.

Validation of Self-administrated Questionnaire for Psychiatric Disorders in Patients with Functional Dyspepsia

Introduction

Psychiatric comorbidity is common in patients with functional dyspepsia (FD) but a good screening tool for psychiatric disorders in gastrointestinal clinical practice is lacking.

Aims

1) Evaluate the performance and optimal cut-off of 12-item General Health Questionnaire (GHQ-12) as a screening tool for psychiatric disorders in FD patients; 2) Compare health-related quality of life (HRQoL) in FD patients with and without psychiatric comorbidities.

Methods

Consecutive patients fulfilling Rome III criteria for FD without medical co-morbidities and gastroesophageal reflux disease were recruited in a gastroenterology clinic. The followings were conducted at 4 weeks after index oesophagogastroduodenoscopy: self-administrated questionnaires on socio-demographics, dyspeptic symptom severity (4-point Likert scale), GHQ-12, and 36-item short-form health survey (SF-36). Psychiatric disorders were diagnosed with Structured Clinical Interview for DSM-IV Axis I Disorders (SCID) by a trained psychiatrist, which served as reference standard.

Results

55 patients underwent psychiatrist-conducted interview and questionnaire assessment. 27 (49.1%) had current psychiatric disorders as determined by SCID (anxiety disorders: 38.2%, depressive disorders: 16.4%). Receiver operating characteristic curve analysis of GHQ-12 revealed an area under curve of 0.825 (95%CI: 0.698-0.914). Cut-off of GHQ-12 at ≥3 gave a sensitivity of 63.0% (95%CI = 42.4-80.6%) and specificity of 92.9% (95%CI = 76.5%-98.9%). Subjects with co-existing psychiatric disorders scored significantly lower in multiple domains of SF-36 (mental component summary, general health, vitality and mental health). By multivariate linear regression analysis, current psychiatric morbidities (Beta = -0.396, p = 0.002) and family history of psychiatric illness (Beta = -0.299, p = 0.015) were independent risk factors for poorer mental component summary in SF-36, while dyspepsia severity was the only independent risk factor for poorer physical component summary (Beta = -0.332, p = 0.027).

Conclusions

Concomitant psychiatric disorders adversely affect HRQoL in FD patients. The use of GHQ-12 as a reliable screening tool for psychiatric disorders allows early intervention and may improve clinical outcomes of these patients.

Plasma vitamin C and tocotrienols changes in response to dietary supplementation among young male adults

BACKGROUND AND AIMS

Intake of the antioxidant vitamins C and E lowers the oxidative stress. The study aimed to determine plasma concentrations of vitamin C and tocotrienols after supplementation of both vitamins in young male adults.

MATERIALS AND METHODS

A total of 64 police recruits were randomly assigned to one of these groups: (a) 500 mg vitamin C (Vitamin C), (b) 200 mg Tocovid (Tocotrienol), (c) combination of 500 mg vitamin C and 200 mg Tocovid (Combination) or (d) placebo (Placebo) for eight-weeks of supplementation followed by six-week washout period.

RESULTS

In Combination group, mean plasma vitamin C concentration significantly increased from baseline 2.86 +/- 1.19 mg/L to 10.37 +/- 1.29 mg/L and 15.63 +/- 1.27 mg/L after four- and eight-week supplementation, respectively. The corresponding figures for alpha-, delta- and gamma-tocotrienols were 9.9 +/- 2.5 ng/ml to 104.1 +/- 19.8 ng/ml and 112.8 +/- 38.0 ng/ml; 2.5 +/- 0.9 ng/ml to 29.9 +/- 7.0 ng/ml and 17.9 +/- 4.7 ng/ml; 19.2 +/- 3.1 ng/ml to 75.2 +/- 24.1 ng/ml and 161.7 +/- 49.9 ng/ml, respectively. In Vitamin C group, plasma vitamin C concentrations were significantly increased. Conversely, concentration of plasma vitamin C in Tocotrienol group increased from baseline of 2.72 +/- 0.20 mg/L to 6.80 +/- 0.63 mg/L and 8.9 +/- 0.77 mg/L respectively. Plasma concentrations of alpha-, delta- and gamma-tocotrienols in this group were significantly elevated. After 6-week washout period, all the elevated concentrations returned to basal levels.

CONCLUSION

The study showed a good bioavailability of these vitamins and increment due to supplementation.

Association of C-reactive protein with type 2 diabetes: prospective analysis and meta-analysis

AIMS/HYPOTHESIS

We examined the association between serum C-reactive protein (CRP) and incident diabetes in a prospective study, and added these data to a literature-based meta-analysis to explore potential sources of heterogeneity between studies.

METHODS

We analysed a case-control study nested within the European Prospective Investigation of Cancer (EPIC)-Norfolk cohort, including 293 incident diabetes cases and 708 controls. We combined 16 published studies on CRP and incident diabetes in a random-effect meta-analysis.

RESULTS

In the EPIC-Norfolk cohort, serum CRP was associated with a higher risk of diabetes after adjusting for age, sex, BMI, family history of diabetes, smoking and physical activity (OR 1.49, comparing the extreme thirds of CRP distribution [95% CI 1.03-2.15], p = 0.03). However, the association was completely attenuated after further adjustment for WHR, serum gamma-glutamyltransferase and serum adiponectin (OR 1.00; 95% CI 0.66-1.51, p = 1.0). In a meta-analysis of 16 published studies with 3,920 incident diabetes cases and 24,914 controls, the RR was 1.72 (95% CI 1.54-1.92), comparing the extreme thirds of CRP distribution, with substantial heterogeneity between studies (I (2) = 52.8%, p = 0.007).

CONCLUSIONS/INTERPRETATION

Initial evidence of association between CRP and incident diabetes was confounded by central adiposity, markers of liver dysfunction and adiponectin in the primary analysis. Despite an overall positive association in the meta-analysis, considerable heterogeneity existed between studies. The degree of adjustment for central adiposity and baseline glycaemia explained some of this heterogeneity and suggests that CRP may not be an independent risk factor for type 2 diabetes.

Primary drug resistance and transmission analysis of HIV-1 in acute and recent drug-naïve seroconverters in Singapore

OBJECTIVES

The aim of the study was to elucidate primary drug resistance and transmission of HIV-1 in acute and recent drug-naïve seroconverters in Singapore.

METHODS

Acute and recent HIV-1 seroconverters were enrolled in the study. The HIV-1 polymerase (pol) gene was sequenced and used for genotypic drug resistance analysis and phylogenetic analysis. HIV-1 transmission clusters were inferred from phylogenetic clustering analysis.

RESULTS

Of the 60 subjects analysed, 95% were men, and 73.3% were men who have sex with men (MSM). Six HIV-1 subtypes were identified, including CRF01_AE (46.7%), subtypes B (30%), B' (15%) and G (1.7%), CRF33_01B (1.7%) and CRF34_01B (5%). Primary genotypic resistance was detected in only one (1.7%) subtype B variant. Thirty-one patients (51.7%) were phylogenetically clustered, of whom 90% reported having local risk exposure, compared with 59% of the patients who were not phylogenetically clustered [odds ratio (OR) 6.35, 95% confidence interval (CI) 1.65-23.95]. MSM (OR 5.63, 95% CI 1.17-27.15), high viral load (OR 4.28, 95% CI 1.37-13.36) and young age (OR 0.92, 95% CI 0.85-0.99) were independently associated with clustered individuals.

CONCLUSIONS

In Singapore, HIV-1 primary resistance is insignificant; individuals with seroconversion account for about half of onward transmission among recently infected seroconverters. MSM, high viral load and young age are factors that facilitate transmission. Early detection of these individuals is of paramount importance for the prevention of HIV-1 transmission.

Validation of medium-pressure UV disinfection reactors by Lagrangian actinometry using dyed microspheres

Lagrangian actinometry (LA) has been demonstrated to represent an alternative to conventional biodosimetry for validation of ultraviolet (UV) disinfection systems used in drinking water treatment. However, previous applications of LA for this purpose have all involved monochromatic (lambda = 254 nm) UV reactor systems. To address this issue, dyed microspheres (DMS) were applied for quantification of dose distribution delivery by field-scale UV reactor systems based on medium-pressure Hg lamp (MP) technology. These MP reactor systems are characterized by polychromatic output. Dose distribution estimates developed by LA for these reactors were reported as equivalent 254 nm distributions. When combined with the UV(254) dose-response behavior for challenge organisms used in simultaneous or parallel biodosimetry experiments, the dose distribution estimates developed from the microspheres yielded estimates of challenge organism inactivation that were in agreement with measured values. For one of the reactors tested, biodosimetry tests were conducted with two challenge organisms that had different UV dose-response behavior; UV dose distribution estimates from LA yielded predictions of microbial inactivation that were in agreement with measured inactivation responses for both challenge organisms for all test conditions. It is likely that the agreement between LA results and biodosimetry data was related, in part, to the agreement between the action spectra of the microspheres and the challenge organisms. Because LA yields a measure of the UV dose distribution delivered by a reactor, the information from LA assays will eliminate many sources of uncertainty in the design and operation of UV systems, thereby allowing for implementation of UV reactor systems that are less expensive than their predecessors, yet more reliable.

Ordered YBCO sub-micron array structures induced by pulsed femtosecond laser irradiation

We report on the formation of organized sub-micron YBa(2)Cu(3)O(7) (YBCO) dots induced by irradiating femtosecond laser pulses on YBCO films prepared by pulse laser deposition with fluence in the range of 0.21 approximately 0.53 J/cm(2). The morphology of the YBCO film surface depends strongly on the laser fluences irradiated. At lower laser fluence (approximately 0.21 J/cm(2)) the morphology was pattern of periodic ripples with sub-micrometer spacing. Slightly increasing the laser fluence to 0.26 J/cm(2) changes the pattern into organized sub-micron dots with diameters ranging from 100 nm to 800 nm and height of 150 nm. Further increase of the laser fluence to over 0.32 J/cm(2), however, appeared to result in massive melting and led to irregular morphology. The mechanism and the implications of the current findings will be discussed. Arrays of YBCO sub-micron dots with T(c) = 89.7 K were obtained.

Persistent dizziness and nausea in patients receiving postoperative epidural pain control after living donor liver transplantation: case reports

Dizziness and nausea are frequent problems among patients receiving patient-controlled epidural analgesia (PCEA) after major surgery. It is important to consider the various etiologies that might cause these adverse events, especially among patients who have undergone massive hepatic resection for living donor liver transplantation (LDLT). We have described 2 LDLT cases with persistent dizziness and nausea postoperatively despite several adjustments in PCEA management. Their symptoms were quickly relieved after suspension of PCEA medication. Our 2 cases of LDLT represented a unique setting for this type of complication.

A study on microwave-induced melt granulation in a single pot high shear processor

Microwave-induced high shear melt granulation was compared with conventional melt granulation performed in the same processor. Admixtures of lactose 200M and anhydrous dicalcium phosphate were granulated with polyethylene glycol 3350. Different heating mechanisms in the two processes necessitated the use of different parameters for process monitoring and control. Mixer power consumption was suitable for monitoring agglomerate growth under microwave-induced heating. Product temperature was a better indicator of agglomeration propensity in conventional melt granulation. These were attributed to the disparities in heat acquisition rates and heating uniformities of the powders as well as variation in baseline mixer power consumption between the two processes.

Impact of helical computed tomography in clinically evident appendicitis

OBJECTIVES

To determine the utility of multidetector computed tomography (MDCT) in patients with clinically evident acute appendicitis and to compare the test characteristics of overall clinical impression, Alvarado scores, and MDCT in suspected appendicitis.

METHODS

A prospective observational cohort study was conducted in two urban emergency departments (ED). Consecutive patients with suspected acute appendicitis were clinically evaluated by an emergency physician who was asked to determine whether appendicitis was clinically evident or not. Elements of the Alvarado scores were collected and all patients then underwent MDCT and a decision to operate, observe, or discharge the patients was made by a surgeon. The final diagnosis was based on surgical pathology or clinical follow-up. The test characteristics of clinical impression, Alvarado scores and MDCT were then calculated and the rates at which acute appendicitis was falsely diagnosed based on clinical impression and MDCT were compared using McNemar's test.

RESULTS

Of 157 study patients, 71 were considered to have clinically evident appendicitis before MDCT and 91 had findings of acute appendicitis on MDCT. 19 of the 71 patients with clinically evident appendicitis did not have appendicitis. 14 of 52 patients with an Alvarado score > or = 8 also did not have appendicitis. Three of 91 patients with acute appendicitis based on MDCT did not have appendicitis. The specificities of clinical impression and Alvarado score > or = 8 were 71.6% and 79.1%, respectively, and these were significantly lower than that of MDCT (95.5%, p<0.05).

CONCLUSION

The performance of abdominal MDCT in patients with a high degree of clinical suspicion for acute appendicitis reduces the number of false positives and has the potential to reduce negative appendectomies.

Constant darkness is a mammalian biological signal

Environmental light is a potent modulator of mammalian circadian rhythm and expression of clock genes. Constant darkness (DD) is regarded as a "free-running" circadian state. In nature, hibernating mammals encounter constant darkness (DD) seasonally. Circadian expression of enzymes involved in fat catabolism, procolipase (CLP) and pancreatic-lipase-related protein 2 (PLRP2), were identified in many peripheral organs of mice during DD but not during regular light/dark (LD) cycles. Circulating 5'-adenosine monophosphate (5'-AMP) was associated with DD-activated gene expression. Synthetic 5'-AMP, when injected into LD mice, activated procolipase expression in their peripheral organs and the animals become severely hypothermic, both key features of hibernating mammals. These findings identified a circadian-regulated metabolic cycle in mammals that may be associated with hypometabolic behaviors such as hibernation and torpor.

Medical physics aspects of cancer care in the Asia Pacific region

Medical physics plays an essential role in modern medicine. This is particularly evident in cancer care where medical physicists are involved in radiotherapy treatment planning and quality assurance as well as in imaging and radiation protection. Due to the large variety of tasks and interests, medical physics is often subdivided into specialties such as radiology, nuclear medicine and radiation oncology medical physics. However, even within their specialty, the role of radiation oncology medical physicists (ROMPs) is diverse and varies between different societies. Therefore, a questionnaire was sent to leading medical physicists in most countries/areas in the Asia/Pacific region to determine the education, role and status of medical physicists.Answers were received from 17 countries/areas representing nearly 2800 radiation oncology medical physicists. There was general agreement that medical physicists should have both academic (typically at MSc level) and clinical (typically at least 2 years) training. ROMPs spent most of their time working in radiotherapy treatment planning (average 17 hours per week); however radiation protection and engineering tasks were also common. Typically, only physicists in large centres are involved in research and teaching. Most respondents thought that the workload of physicists was high, with more than 500 patients per year per physicist, less than one ROMP per two oncologists being the norm, and on average, one megavoltage treatment unit per medical physicist.There was also a clear indication of increased complexity of technology in the region with many countries/areas reporting to have installed helical tomotherapy, IMRT (Intensity Modulated Radiation Therapy), IGRT (Image Guided Radiation Therapy), Gamma-knife and Cyber-knife units. This and the continued workload from brachytherapy will require growing expertise and numbers in the medical physics workforce. Addressing these needs will be an important challenge for the future.

Building partnerships to address the HIV epidemic

INTRODUCTION

Batam is one of the islands comprising the Riau Province in Indonesia, and is closest to Singapore. It is a popular destination of many Singaporeans. Surveillance reports among commercial sex workers conducted in Batam showed the prevalence rate of human immunodeficiency virus (HIV) is 16.2 percent. At the end of 2006, the total number of HIV-infected Singaporeans was 3,060, the majority being infected via heterosexual transmission. The aim of the Indonesian government is to rapidly scale up HIV treatment to those needing it. One of the factors critical to the rapid scale-up is healthcare worker training.

METHODS

An intersectoral collaboration addressing the issue of HIV care and treatment with a hospital in Batam was created. The first activity of the collaboration was a two-day HIV training course conducted in February 2007. The aim of the course was to provide a basic understanding of HIV, as well as knowledge on common opportunistic infections that may present to a general hospital or clinical setting.

RESULTS

34 doctors from 23 institutions in Batam and three doctors from two hospitals in the Riau Islands attended the two-day HIV training course. The participants found the training very useful and highly relevant.

CONCLUSION

This first HIV training provided a foundation to build on further HIV education. It is our belief that through the HIV training programme, there will be more awareness of HIV among the various medical institutions in Batam. As the HIV epidemic knows no borders, working with neighbouring countries is one strategy that deserves attention.

Using direct nanoimprinting to study extraordinary transmission in textured metal films

In this paper, we describe a thermal embossing imprint method, which we name "nano-imprinting in metal" (NIM), for patterning metal films with a variety of profiles. Metal films exhibiting either perforated hole-arrays or corrugated structures with various surface morphologies can be fabricated rapidly. The SPR phenomenon allowed energy coupling to the other side of the textured metal film, causing a dramatic increase in the transmission. As a technique for readily controlling the working wavelength and transmittance, the NIM method has great potential for application in various optoelectronic devices.

Adenocarcinoma of the duodenum

Adenocarcinoma of the duodenum is an exceedingly rare disorder. Its vague and non-specific symptoms often lead clinicians and patients to suspect other more benign differential diagnoses. Improved endoscopy and radiology have enabled more of these cases to be unearthed. Definitive surgery is the only means of potential cure, with the prognosis being significantly better for node-negative patients. We present a case of a 52-year-old man who underwent a Whipple's operation for this uncommon disease and a literature review of the subject.