Distributions of PCDD/Fs, PCBs, and PCNs in coastal sediments collected from major industrial bays in South Korea

Polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polychlorinated naphthalenes (PCNs) were assessed in coastal sediments from industrial bays in South Korea to evaluate the pollution levels and their environmental impact. The mean sediment concentrations of Σ17 PCDD/Fs, Σ18 PCBs, and Σ15 PCNs were 198 ± 140, 3427 ± 7037, and 85 ± 336 pg/g dw, respectively. Generally, pollutant concentrations in the inner bay were higher than those in the outer bay, indicating the influence of industrial emissions and harbor activities. The primary sources were identified as steel manufacturing and wastewater treatment plants for PCDD/Fs, harbor and shipbuilding activities for PCBs, and combustion-related sources for PCNs. Notably, PCDD/F concentrations exceeded sediment guideline values. The combined effects of PCDD/Fs and PCBs demonstrated adverse impacts on aquatic organisms. Hence, the release of toxic pollutants into the marine environment could have potential biological effects due to the combined impact of these various compounds.

Spatial distribution, source identification, and anthropogenic effects of brominated flame retardants in nationwide soil collected from South Korea

Soil samples were collected at 61 sites of the national monitoring network for persistent organic pollutants (POPs) in South Korea. The target compounds were brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), hexabromocyclododecanes (HBCDDs), and tetrabromobisphenol A (TBBPA). The mean concentrations of Σ₂₇ PBDEs, Σ₃ HBCDDs, and TBBPA in soil were 222, 17.2, and 4.4 ng/g, respectively, but PBBs were not detected. Industrial sites had statistically higher BFR concentrations than suburban sites but no significant difference compared with urban sites. The commercial deca-BDE mixtures were the most likely source of PBDE contamination in the soil samples, with the minor influence of commercial penta-BDE and octa-BDE mixtures. The profiles of HBCDDs in most soil samples differed from those in the powder types of technical HBCDD mixtures, indicating that they are affected by the HBCDDs contained in commercial products and the conversion of HBCDD diastereoisomers (γ-HBCDD to α-HBCDD) in the environment. The concentrations of Σ₂₇ PBDEs, Σ₃ HBCDDs, and TBBPA were significantly correlated with population density, gross domestic product, and the number of companies (p < 0.01), indicating a direct impact of anthropogenic activities. Significant correlations among BFRs were determined (0.63 < r < 0.74, p < 0.01), suggesting that these pollutants had similar sources. Relatively good correlations (0.44 < r < 0.98, p < 0.01) between BDE-209 and other light BDEs (except for BDE-71, -77, -126, -156, and -205) might result from the degradation of heavy BDEs under anaerobic and natural sunlight conditions. To the best of our knowledge, this study provides the most comprehensive soil monitoring data for various BFRs in South Korea. Furthermore, it is the first report on soil contamination by deca-BDE, HBCDDs, and TBBPA in South Korea.

Nationwide levels and distribution of endosulfan in air, soil, water, and sediment in South Korea

We investigated the levels and distribution patterns of α- and β-endosulfan and endosulfan sulfate in air, soil, water, and sediment samples collected from the South Korean persistent organic pollutants (POPs) monitoring networks. In the air samples, the highest concentrations of the total (Σ₃) endosulfan (50.3-611 pg/m³, mean: 274 pg/m³) were observed during summer. Spearman analysis revealed a good correlation between agricultural land area and atmospheric concentrations of Σ₃ endosulfan except during winter. Regardless of the season, the ratio of the two isomers (α/β) was 3.6-4.9 in the air samples, higher than that observed in technical mixtures (2.0-2.3), possibly due to the higher volatility of α-endosulfan, compared to β-endosulfan. Concentrations of Σ₃ endosulfan in the soil samples (n.d.-13.4 ng/g, mean: 0.8 ng/g) were not significantly different except at some stations adjacent to large areas of farmland. The average levels of Σ₃ endosulfan in the water and sediment samples were 2.1 ng/L and 0.1 ng/g dw, respectively. In analyzing the four largest rivers, it was observed that a few water stations during spring and fall and sediment stations in fall had high concentrations of the two isomers and endosulfan sulfate, particularly around the Yeoungsan and Nakdong Rivers near large areas of agricultural land. Endosulfan sulfate was dominant at most water and sediment sampling stations. This study demonstrates that the endosulfan found in most environmental compartments most probably derives from agricultural areas despite its ban as a pesticide. On the other hand, given that it was also detected in industrial and urban areas, in which pesticide application does not occur, it can be conjectured that endosulfan is aerially transported at higher temperatures and continuously circulates within the environment.

Determination of Ginsenosides (Ginseng Saponins) in Dry Root Powder from Panax ginseng, Panax quinquefolius, and Selected Commercial Products by Liquid Chromatography: Interlaboratory Study

Twelve collaborating laboratories assayed 4 products, namely, Panax ginseng, Panax quinquefolius, and 2 ginseng products, for 6 ginsenosides: Rb1, Rb2, Rc, Rd, Re, andRg1. Collaborators also received a negative control for the recovery study. Pure ginsenosides were provided as reference standards for the liquid chromatography (LC) analysis and the system suitability tests. The LC analyses were performed on the methanol extract using UV detection at 203 nm. For P. ginseng, individual ginsenosides were consistent in their means; repeatability standard deviations (RSDr)rangedfrom4.17to5.09% and reproducibility standard deviations (RSDR) ranged from 7.27 to 11.3%. For P. quinquefolius, the Rb1 and Rb2 ginsenosides were higher and lower in concentration than P. ginseng, with RSDr values of 3.44 and 6.60% and RSDR values of 5.91 and 12.6% respectively, and other analytes at intermediate precisions. For ginseng commercial products, RSDr values ranged from 3.39 to 8.12%, andRSDR values ranged from 7.65 to 16.5%. A recovery study was also conducted for 3 ginsenosides: Rg1, Re, andRb1. The average recoveries were 99.9, 96.2, and 92.3%, respectively. The method is not applicable for the determination of Rg1 and Re in ginseng product at levels &lt;300 mg/kg.

Distribution and diastereoisomeric profiles of hexabromocyclododecanes in air, water, soil, and sediment samples in South Korea: Application of an optimized analytical method

In this study, the levels and distribution patterns of HBCD diastereoisomers in air, water, soil, and sediment samples in South Korea were investigated after optimizing the UPLC-MS/MS analytical process. Extraction and cleanup efficiencies were tested using several different extraction solvents and adsorbents. Dichloromethane was selected as the base extraction solvent, and multi-layer silica gel (MSG) and MSG-alumina columns were selected for the removal of HBCDs from complex environmental matrices. The concentration of Ʃ₃ HBCDs was 22-133 pg/m³, 10-128 ng/g, 0.2-151 ng/L, and 0.5-552 ng/g dw for air, soil, water, and sediment samples, respectively. Relatively higher concentrations of Ʃ₃ HBCDs were observed at stations adjacent to industrial facilities (e.g., rubber and plastic, textile, chemical, fabricated metal, and wholesale trade factories) associated with the use of commercial HBCDs. The proportion of γ-HBCD in the soil (48.3-86.2%) and sediment (54.2-78.1%, except for one station) samples was similar to that found in technical and commercial HBCDs. In contrast, α-HBCD (52.3-71.2%) was dominant in all air samples, while the water samples displayed no clear trend in their diastereoisomer profiles. As the first nationwide report on HBCD diastereoisomers in the environment, this study demonstrates that most environmental compartments in South Korea are moderately contaminated with HBCDs.

Abundance of diet-derived polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in the bodies and nests of the yellow-legged hornet Vespa velutina nigrithorax and risks to human health in South Korea

Detecting polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in an organism's environment is ecologically significant. In particular, the detection of PCDD/Fs in organisms consumed as food suggests the possibility of human health risks. In South Korea, there is a unique custom in which social wasps, such as hornets, have been used as ingredients in traditional liquor. Thus, we investigated the concentrations and patterns of PCDD/Fs for the most common social wasps, the yellow-legged hornet (Vespa velutina nigrithorax), and estimated human health risks based on potential dietary exposure in traditional liquor made from the polluted wasps and their nests. The mean concentration of ∑₁₇ PCDD/Fs in the wasps and nests of V. v. nigrithorax was 33.59 pg/g (median 25.31 pg/g), corresponding to 0.65 pg World Health Organization - Toxic equivalency factor (WHO-TEQ/g) (median 0.49 pg WHO-TEQ/g). The levels of ∑₁₇ PCDD/Fs from the nests of V. v. nigrithorax were higher than those in the adults and larvae. As a result of this risk assessment, the daily intake of traditional liquor made with these wasps and their nests was found to be below safety levels; however, there could still be a possibility for health risks due to the detection of PCDD/Fs from organism. Therefore, continuous monitoring of environmental contaminants, including PCDD/Fs in wasps and nests, is required in order to evaluate human health risks associated with the consumption of traditional liquor made with these biological substances. In addition, the results of this study can be used to calculate dietary exposure to PCDD/Fs and the extent of risk to food in which the organism is consumed.

Systemic lupus erythematosus is a risk factor for cancer: a nationwide population-based study in Korea

OBJECTIVE

Specific differences in cancer risk have been observed between systemic lupus erythematosus patients and the general population. Although meta-analyses have estimated cancer incidence in systemic lupus erythematosus patients, results have been inconclusive. Hence, we aimed to assess malignancy risk in systemic lupus erythematosus patients, compared to the risk in the general population.

METHODS

Systemic lupus erythematosus patients ( n = 21,016; mean age 41.67 ± 13.14 years; female 90.22%) were selected from the Korean National Health Insurance Service database between 2008 and 2014. Age- and sex-matched controls were randomly sampled in a 5:1 ratio ( n = 105,080).

RESULTS

During the 7 years of follow up, malignancy was detected in 763 (3.63%) systemic lupus erythematosus patients and 2667 (2.54%) controls. Systemic lupus erythematosus patients had a higher risk of malignancy than controls (odds ratio 1.44; 95% confidence interval 1.327-1.559), after multivariate adjustment. Systemic lupus erythematosus patients had a higher odds ratio for developing cervical, thyroid, ovarian, and oral cancer, as well as lymphoma, leukemia, and multiple myeloma than controls. Based on subgroup analysis, male systemic lupus erythematosus patients and patients younger than 40 years showed the highest lymphoma risk.

CONCLUSIONS

Systemic lupus erythematosus might be an independent risk factor for cancer. Therefore, the importance of cancer screening programs should be emphasized in systemic lupus erythematosus patients. Our study is the first large nationwide cohort study for evaluating the risk of cancer in systemic lupus erythematosus patients.

Remifentanil vs. Lignocaine for Attenuating the Haemodynamic Response during Rapid Sequence Induction Using Propofol: Double-Blind Randomised Clinical Trial

This study was conducted to determine whether lignocaine or remifentanil effectively attenuate the response to endotracheal intubation during rapid sequence induction. Forty-eight patients were randomly divided into three groups: Group NS (n=16) received normal saline 0.1 ml/kg, Group L (n=16) received lignocaine 1.5 mg/kg, and Group R (n=16) received remifentanil 1 /μg/kg. Anaesthesia was induced with propofol 2 mg/kg after glycopyrrolate 0.2 mg IV. Each study drug was given intravenously over 30 seconds after loss of consciousness. Cricoid pressure was applied until intubation. Succinylcholine 1.0 mg/kg was administered to facilitate tracheal intubation. After intubation, the patient's lungs were ventilated with sevoflurane 1% and nitrous oxide 50% in oxygen. Mean arterial pressure and heart rate were recorded before induction, at loss of consciousness, immediately before laryngoscopy and every minute after intubation for 10 minutes. Mean arterial pressure fell following propofol in all groups. The maximum increase in mean arterial pressure in Group NS and Group L were 46% and 38% respectively above the baseline value one minute after intubation, whereas the mean arterial pressure in Group R increased only back to the baseline value. Heart rate in Group NS and Group L were increased by 27% and 33% above baseline value respectively one minute after intubation, while that in Group R was increased only to the baseline value. The results indicate that remifentanil 1 μg/kg, but not lignocaine 1.5 mg/kg, effectively attenuates the haemodynamic response to endotracheal intubation during rapid sequence induction using propofol.

Survival outcome differences based on treatments used and knowledge of the primary tumour site for patients with cancer of unknown and known primary in Ontario

Introduction

Patients with cancer of unknown primary (cup) have pathologically confirmed metastatic tumours with unidentifiable primary tumours. Currently, very little is known about the relationship between the treatment of patients with cup and their survival outcomes. Thus, we compared oncologic treatment and survival outcomes for patients in Ontario with cup against those for a cohort of patients with metastatic cancer of known primary site.

Methods

Using the Ontario Cancer Registry and the Same-Day Surgery and Discharge Abstract databases maintained by the Canadian Institute for Health Information, we identified all Ontario patients diagnosed with metastatic cancer between 1 January 2000 and 31 December 2005. Ontario Health Insurance Plan treatment records were linked to identify codes for surgery, chemotherapy, or therapeutic radiation related to oncology. Multivariable Cox regression models were constructed, adjusting for histology, age, sex, and comorbidities.

Results

In 45,347 patients (96.3%), the primary tumour site was identifiable, and in 1743 patients (3.7%), cup was diagnosed. Among the main tumour sites, cup ranked as the 6th largest. The mean Charlson score was significantly higher (p < 0.0001) in patients with cup (1.88) than in those with a known primary (1.42). Overall median survival was 1.9 months for patients with cup compared with 11.9 months for all patients with a known-primary cancer. Receipt of treatment was more likely for patients with a known primary site (n= 35,012, 77.2%) than for those with cup (n = 891, 51.1%). Among patients with a known primary site, median survival was significantly higher for treated than for untreated patients (19.0 months vs. 2.2 months, p < 0.0001). Among patients with cup, median survival was also higher for treated than for untreated patients (3.6 months vs. 1.1 months, p < 0.0001).

Conclusions

In Ontario, patients with cup experience significantly lower survival than do patients with metastatic cancer of a known primary site. Treatment is associated with significantly increased survival both for patients with cup and for those with metastatic cancer of a known primary site.

Systemic lupus erythematosus is a risk factor for cardiovascular disease: a nationwide, population-based study in Korea

OBJECTIVE

To investigate the incidence and clinical significance of cardiovascular disease in systemic lupus erythematosus patients.

METHODS

We included systemic lupus erythematosus patients ( n = 18,575) without previous cardiovascular disease and age- and sex-matched individuals without systemic lupus erythematosus (controls; n = 92,875) from the Korean National Health Insurance Service database (2008-2014). Both cohorts were followed up for incident cardiovascular disease and death until 2015.

RESULTS

During follow up, myocardial infarction occurred in 203 systemic lupus erythematosus patients and 325 controls (incidence rate: 1.76 and 0.56 per 1000 person-years, respectively), stroke occurred in 289 patients and 403 controls (incidence rate: 2.51 and 0.70 per 1000 person-years, respectively), heart failure occurred in 358 patients and 354 controls (incidence rate 3.11 and 0.61 per 1000 person-years, respectively), and death occurred in 744 patients and 948 controls (incidence rate 6.54 and 1.64 per 1000 person-years, respectively). Patients with systemic lupus erythematosus had higher risks for myocardial infarction (hazard ratio: 2.74, 95% confidence interval: 2.28-3.37), stroke (hazard ratio: 3.31, 95% confidence interval: 2.84-3.86), heart failure (hazard ratio: 4.60, 95% confidence interval: 3.96-5.35), and cardiac death (hazard ratio: 3.98, 95% confidence interval: 3.61-4.39).

CONCLUSIONS

Here, systemic lupus erythematosus was an independent risk factor for cardiovascular disease, thus cardiac assessment and management are critical in systemic lupus erythematosus patients.

Gemigliptin, a novel dipeptidyl peptidase-IV inhibitor, exerts a synergistic cytotoxicity with the histone deacetylase inhibitor PXD101 in thyroid carcinoma cells

PURPOSE

The influence of the dipeptidyl peptidase-IV inhibitor gemigliptin alone or in combination with the histone deacetylase inhibitor PXD101 on survival of thyroid carcinoma cells was investigated.

METHODS

SW1736, TPC-1, 8505C and BCPAP human thyroid carcinoma cells were used. To assess cell survival, cell viability, the percentage of viable cells and dead cells, cytotoxic activity, ATP levels and FACS analysis were measured. To validate the impact of gemigliptin combined with PXD101, the interactions were estimated by obtaining combination index in cells treated with two agents.

RESULTS

In cells treated with gemigliptin or PXD101, cell viability, the percentage of viable cells and ATP levels were reduced, and the percentage of dead cells and cytotoxic activity were elevated. In cells treated with both gemigliptin and PXD101, compared with PXD101 alone, cell death was augmented, and all of the combination index values were lower than 1.0, suggesting the synergism between gemigliptin and PXD101. The percentage of apoptotic cells, and the protein levels of Bcl2 and cleaved poly (ADP-ribose) polymerase were elevated, and the protein levels of xIAP and survivin were reduced. The protein levels of phospho-Akt and phospho-AMPK were elevated, and cell migration was reduced.

CONCLUSIONS

Our results demonstrate that gemigliptin induces cytotoxicity in thyroid carcinoma cells. Moreover, gemigliptin has a synergistic activity with PXD101 in the induction of cell death through involvement of Bcl2 family proteins, xIAP and survivin as well as mediation of Akt and AMPK in thyroid carcinoma cells.

Two-dimensional plasmonic grating for increased quantum efficiency in midwave infrared nBn detectors with thin absorbers

We demonstrate a strategy for increasing the operating temperatures of nBn midwave infrared (MWIR) focal plane arrays, based on the use of two-dimensional plasmonic gratings to enhance the quantum efficiency (QE) of structures with very thin absorbers. Reducing the absorber volume correspondingly reduces the dark current in a diffusion-limited photodiode, while light trapping mediated by the plasmonic grating increases the net absorbance to maintain high QE. The plasmonically enhanced nBn MWIR sensors with absorber thicknesses of only 0.5 μm exhibit peak internal QEs as high as 57%, which enables a 5-fold reduction in dark current. Numerical simulations indicate the potential for further improvement.

Perisomatic changes in h-channels regulate depressive behaviors following chronic unpredictable stress

Chronic stress can be a precipitating factor in the onset of depression. Lentiviral-mediated knockdown of HCN1 protein expression and reduction of functional I_h produce antidepressant behavior. However, whether h-channels are altered in an animal model of depression is not known. We found that perisomatic HCN1 protein expression and I_h-sensitive physiological measurements were significantly increased in dorsal but not in ventral CA1 region/neurons following chronic unpredictable stress (CUS), a widely accepted model for major depressive disorder. Cell-attached patch clamp recordings confirmed that perisomatic I_h was increased in dorsal CA1 neurons following CUS. Furthermore, when dorsal CA1 I_h was reduced by shRNA-HCN1, the CUS-induced behavioral deficits were prevented. Finally, rats infused in the dorsal CA1 region with thapsigargin, an irreversible inhibitor of the SERCA pump, exhibited anxiogenic-like behaviors and increased I_h, similar to that observed following CUS. Our results suggest that CUS, but not acute stress, leads to an increase in perisomatic I_h in dorsal CA1 neurons and that HCN channels represent a potential target for the treatment of major depressive disorder.

Evaluation of abundance of artificial radionuclides in food products in South Korea and sources

Food samples are collected nationwide from January 2016 to February 2017 and their contents of artificial radionuclides are measured to address the growing concerns regarding the radioactive contamination of food products in Korea. Specifically, 900 food samples are collected for this study and their contents of representative artificial radionuclides ¹³⁴Cs, ¹³⁷Cs, ^239,240Pu, and ⁹⁰Sr are analyzed. The analysis shows that the activity concentrations of ¹³⁷Cs in fish range from minimum detectable activity (MDA) to 340 mBq/kg of fresh weight. The concentration factor (CF) determined for ¹³⁷Cs as a measure of its bioavailability is calculated to be ca. 74 and found to be very similar to that (100) recommended by the International Atomic Energy Agency. With an MDA of <0.221 mBq/kg, the results reveal that ^239,240Pu values in fish are below the MDA. The activity concentrations of ¹³⁷Cs and ⁹⁰Sr are lower than the MDA in both shellfish and seaweed, while the activity concentrations of ^239,240Pu in shellfish range from 0.26 to 2.18 mBq/kg, and for seaweed samples range from 2.07 to 3.38 mBq/kg. The atom ratios of ²⁴⁰Pu/²³⁹Pu in shellfish caught at the Korean coast vary from 0.209 to 0.237, with a mean of 0.227. The higher ²⁴⁰Pu/²³⁹Pu atom ratio determined in shellfish is thought to be caused by the plutonium transported from the Pacific Proving Grounds rather than other sources such as the Fukushima nuclear power plant accident. The activity concentrations of ¹³⁷Cs in mushrooms are found to vary from 1.0 to 21.4 Bq/kg, with the highest concentrations observed in the Oak (shiitake) and Sarcodon asparatus. ¹³⁴Cs is detected in three mushroom specimens collected from Jeju Island and about 3-3.6% of ¹³⁷Cs present in the wild mushrooms native to the Jeju Island are introduced as a result of the Fukushima nuclear plant accident. The annual effective doses of ¹³⁷Cs received through consumption of mushrooms and fish are 2.0 × 10^-4 mSv yr^-1 and 3.9 × 10^-5 mSv yr^-1, and those values are negligible compared to the annual effective doses limit of 1 mSv yr^-1.

Monitoring and risk assessment of polychlorinated biphenyls (PCBs) in agricultural soil from two industrialized areas

For monitoring and risk assessment, levels and distributions of Σ₂₉ PCBs in paddy soil samples collected from Gwangyang (10 sites) and Ulsan (20 sites), heavily industrialized cities in Korea, were investigated using high-resolution gas chromatography/high-resolution mass spectrometry. Overall, total concentrations of Σ₂₉ PCBs in Gwangyang (216.4-978.6 pg g^-1 dw) and Ulsan (273.8-1824.1 pg g^-1 dw) were higher than those (106.6-222.6 pg g^-1 dw) in agricultural soil from Anseong in Korea. The TEQ (toxic equivalency) values from Gwangyang (0.06-0.40 ng TEQ kg^-1 dw) and Ulsan (0.06-0.22 ng TEQ kg^-1 dw) were higher than those (0.04-0.11 ng TEQ kg^-1 dw) in Anseong but lower than the WHO threshold level (20 ng TEQ kg^-1). However, one of the most toxic congeners, PCB 126, gave the highest concentration, possibly posing a risk to the biota. Seven indicator PCB congeners contributed to 50-80% of the total concentration of Σ₂₉ PCBs, indicating the 7 PCBs can be used as valuable indicators for monitoring. The principal component analysis and cluster analysis for the homologue profiles of PCBs indicated that all the samples from both cities had the similar PCB contamination patterns, and the major sources of the PCB contamination were most likely from the usage of Aroclor 1254 than those of Aroclors 1242 and 1260. These PCB technical mixtures were possibly significantly used by various industries including iron and steel industries in Gwangyang and petrochemical and shipbuilding industries in Ulsan.

Increase in resting heart rate over 2 years predicts incidence of diabetes: A 10-year prospective study

OBJECTIVE

The association between resting heart rate (RHR) and the development of diabetes has yet to be fully elucidated, and the relationship between changes in RHR and incidence of diabetes also remains unclear. Our study aimed to investigate the association between changes in RHR over 2 years and the risk of diabetes.

METHODS

A total of 7416 adults without diabetes were included. All had participated in the Korean Genome and Epidemiology Study, a community-based, 10-year prospective study in which RHR was measured at baseline and 2 years later. Incident diabetes was defined as fasting blood glucose ≥126mg/dL, 2-h post-load glucose ≥200mg/dL during a 75-g oral glucose tolerance test or current use of diabetes medication. The relative risk of diabetes associated with the 2-year change in RHR was calculated using Cox models.

RESULTS

During the 10-year follow-up, 1444 (19.5%) developed diabetes. Compared with RHR increases <5 beats per minute (bpm) over 2 years, increases >10bpm were significantly associated with development of diabetes (adjusted hazard ratio: 1.31, 95% confidence interval: 1.06-1.60), even after adjusting for glycometabolic parameters and baseline RHR. This significant association was attenuated in people who exercised regularly (P=0.650), but remained significant in those not doing any regular exercise (P=0.010).

CONCLUSION

An increase in RHR over a 2-year follow-up period is significantly associated with a risk of diabetes, independently of baseline RHR and glycometabolic parameters. Further investigations into ways to control RHR as a potential preventative measure against the development of diabetes are now needed.

Distribution of bisphenol A in the neuroendocrine organs of female rats

The distribution of 14C-bisphenol A (BPA) in plasma and neuroendocrine organs was determined in Fischer 344 female rats following three oral doses (0.1, 10 or 100 mg/kg). Plasma and tissue maximum concentrations (Cmax) were reached within 15-30 min of dosing. Plasma areas-under-the-curve (AUC) ranged from 0.06 to 53.9 mg-h/mL. The AUCs of the pituitary gland and uterus/gonads were 16-21% higher than that of plasma. The AUCs of hypothalamus and the rest of the brain were 43.7% and 77% of the plasma AUCs, respectively. In the brain tissue, the exposure increased linearly with the oral dose, as the dose was increased from 0.1 to 10 and 100 mg/kg; the exposure in the brain relative to the plasma increased by factors of 1, 1.19 and 1.24. This indicates that the brain barrier systems do not limit the access of the lipophilic BPA to the brain. The increases of the uterus/gonads relative to the plasma were 1, 1.07 and 1.04. Tissue partitioning was also examined in vitro by the uptake of 14C-BPA. The BPA tissue/blood partition coefficients were as follows: heart, 7.5; liver, 6.1; kidney, 6.4; fat, 3.6; muscle, 2.6; breast, 3.6; ovaries, 9.1; uterus, 5.9; stomach, 5.1; and small intestine, 6.7. The tissue/cerebrospinal fluid partition coefficients were as follows: pituitary gland, 12.8; brain stem, 6.1; cerebellum, 6.4; hippocampus, 7.1; hypothalamus, 6.1; frontal cortex, 4.9; and caudate nucleus, 6.8.

Interband cascade lasers with long lifetimes

Narrow-ridge interband cascade lasers were subjected to accelerated aging. The aging curves were statistically evaluated by a log-normal distribution of the failure time, and by the mixed effects of the degradation parameters. Based on 10,000 h of output power trend data for lasers operating at 90°C and the maximum cw power, an unexpectedly long lifetime is predicted. The projected lifetimes range from about 500,000 h (57 years) for the linear degradation model to 183,000 h (21 years) for the exponential one.

Generation of Charged Nanoparticles During Thermal Evaporation of Silver at Atmospheric Pressure

The generation of charged silver nanoparticles in the gas phase during thermal evaporation of silver at atmospheric pressure was confirmed by the nano-differential mobility analyzer (DMA). Effects of the evaporation temperature, the nitrogen gas flow rate and the amount of silver to be evaporated on the size distribution of charged nanoparticles (CNPs) were examined. Both positively and negatively-charged nanoparticles were generated under all processing conditions adopted in this study. The deposition behavior of CNPs was affected by the gas flow, which is affected by the temperature gradient in the reactor and by the applied electric bias. The electric bias, which not only enhanced the film growth rate but also produced a much denser film surface, turned out to be an important process parameter under the condition where an appreciable amount of CNPs is generated.

Gain and loss as a function of current density and temperature in interband cascade lasers

We characterize the internal efficiency, internal loss, and optical gain versus current density in 7-stage interband cascade lasers operating at λ=3.1 and 3.45 μm using a cavity-length study of the external differential quantum efficiency (EDQE) and threshold current density at temperatures between 300 and 345 K. We find that the pronounced efficiency droop of the EDQE at high current densities is primarily due to an increase in the internal loss rather than a reduction in the internal efficiency. On the other hand, if the current density J is fixed, the temperature variation of the EDQE at that J is due primarily to a decrease of the internal efficiency. The gain versus current density is fit well by a logarithmic relationship, although the magnitude of the experimental gain is >20% below the theoretical estimate.

Mid-infrared multi-mode absorption spectroscopy using interband cascade lasers for multi-species sensing

An interband cascade laser (ICL) operating at 3.7 μm has been used to perform multimode absorption spectroscopy, MUMAS, at scan rates up to 10 kHz. Line widths of individual modes in the range 10-80 MHz were derived from isolated lines in the MUMAS signatures of HCl. MUMAS data for methane covering a spectral range of 30 nm yielded a detection level of 30 μbar·m for 1 s measurement time at 100 Hz. Simultaneous detection of methane, acetylene, and formaldehyde in a gas mixture containing all three species is reported.

Development of a mitochondria-targeted Hsp90 inhibitor based on the crystal structures of human TRAP1

The mitochondrial pool of Hsp90 and its mitochondrial paralogue, TRAP1, suppresses cell death and reprograms energy metabolism in cancer cells; therefore, Hsp90 and TRAP1 have been suggested as target proteins for anticancer drug development. Here, we report that the actual target protein in cancer cell mitochondria is TRAP1, and current Hsp90 inhibitors cannot effectively inactivate TRAP1 because of their insufficient accumulation in the mitochondria. To develop mitochondrial TRAP1 inhibitors, we determined the crystal structures of human TRAP1 complexed with Hsp90 inhibitors. The isopropyl amine of the Hsp90 inhibitor PU-H71 was replaced with the mitochondria-targeting moiety triphenylphosphonium to produce SMTIN-P01. SMTIN-P01 showed a different mode of action from the nontargeted PU-H71, as well as much improved cytotoxicity to cancer cells. In addition, we determined the structure of a TRAP1-adenylyl-imidodiphosphate (AMP-PNP) complex. On the basis of comparative analysis of TRAP1 structures, we propose a molecular mechanism of ATP hydrolysis that is crucial for chaperone function.

Antifeedants against Acusta despesta from the Japanese Cedar, Cryptomeria japonica

During our studies on the components in Japanese cedar, Cryptomeria japonica, we found that the crude methanol extract of C. japonica showed intense antifeeding activity against one snail species, Acusta despesta, which is well-known as a pest of many vegetables and crops.

The active components in the extract were separated into the hexane and ethyl acetate soluble fractions. From the active ethyl acetate soluble fraction, two norlignans, sequirin-C and agatharesinol, were isolated and identified as the active compounds. Both compounds inhibited feeding behavior of A. despesta at 30 μg/cm2 and 40 μg/cm2 concentrations, respectively, when applied by an eggplant leaf or filter paper containing 20 μl of 5% sucrose solution.

Instrumental and bioanalytical measures of dioxin-like compounds and activities in sediments of the Pohang Area, Korea

Pohang is a mid-sized city in which Korea's largest manufacturer of steel is located. The Hyeongsan River, which runs through Pohang and empties into Yeongil Bay, is therefore expected to be affected by various municipal and industrial inputs. In order to characterize aryl hydrocarbon receptor (AhR)-mediated activities in sediments from the Pohang area, a total of eight locations along the Hyeongsan River were chosen and 16 sediment samples were collected during two sampling campaigns in 2010. Organic extracts of sediments were characterized by both quantitative chemical analyses of dioxin-like chemicals and the in vitro H4IIE-luc bioassay. Significant dioxin-like activities were observed in sediments from industrial and municipal areas, which indicates that most of the dioxin-like chemicals were associated with surrounding anthropogenic sources. In general, responses of the H4IIE-luc assay were significantly correlated with concentrations of target compounds including dioxins, furans, co-planar PCBs, and dioxin-like PAHs. A potency balance analysis indicated that instrumentally derived TCDD equivalents (TEQs) explained about 77% of the bioassay-derived TCDD equivalents (TCDD-EQs). Among the target chemicals measured, certain penta-chlorinated dioxin and furan compounds accounted for the majority of dioxin-like activities associated with sediments. Compositional analysis of target chemicals the sources of such dioxin-like activities were mainly derived from the local activities such as the iron and steel industries. Concentrations and activities of AhR agonists were similar to what was measured approximately 10 years ago. Thus, while AhR agonists seem to be persistent in sediments there seem to have been no large increases in these chemicals in the Pohang area.

Expression of heat shock protein 90 in the kidneys of diabetic db/db mice

OBJECTIVE

To identify novel genes regulated in diabetic nephropathy.

MATERIALS AND METHODS

Total RNA from the renal cortex of db/+ and db/db mice was isolated and DNA microarrays specific for diabetes signaling pathways were used for expression profiling. Expression of mRNA and protein was determined by RT-PCR and western blotting. The terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick-end labeling (TUNEL) assay and immunohistochemical staining were assessed in renal cortex of db/db mice.

RESULTS

Microarray data revealed that 7 genes show up- or down-regulated pattern and diabetic mice specifically decreased heat shock protein (Hsp) 90α expression of genes compared to control mice (diabetic mice 0.68 vs. control mice 1 relative density). Expression of Hsp90α mRNA and Hsp90 protein was significantly decreased in the renal cortex of diabetic mice. However, Hsp70 mRNA and protein expression was not changed. Apoptosis was increased in glomeruli of diabetic mice due to increased expression of cleaved caspase-3 and Bax.

CONCLUSIONS

Our results suggest that Hsp 90 expression was decreased in diabetic glomeruli and decreased Hsp90 expression may mediate podocyte apoptosis in type 2 diabetic kidneys.

Akt inhibition enhances the cytotoxic effect of apigenin in combination with PLX4032 in anaplastic thyroid carcinoma cells harboring BRAFV600E

Aim of the present study was to evaluate the effect of apigenin in combination with BRAFV600E inhibitor PLX4032 on cell survival, and to investigate the influence of Akt inhibition on the combined effect of apigenin and PLX4032 in ATC cells harboring BRAFV600E. In 8505C and FRO cells harboring BRAFV600E, after treatment of apigenin and PLX4032, the cell viability decreased, and the percentage of dead cells increased in a time- and concentration-dependent manner, respectively. In apigenin- and PLX4032- treated cells, compared with apigenin alone-treated cells, the cell viability was lessened, and the percentage of dead cells was multiplied. In the addition of PLX4032 to apigenin, compared with the treatment of apigenin alone, the protein levels of cleaved PARP-1 and cleaved caspase-3 were elevated, and phospho-ERK protein levels were reduced, and the protein levels of total ERK, c-Myc, BRAF, phospho-Akt, phospho-p70S6K and phospho-4EBP1 were not varied. Compared with the treatment of PLX4032 alone, phosphop70S6K protein levels were reduced, and the other protein levels were not altered. Phospho-ERK protein levels were reduced only in 8505C cells. Under the co-treatment of apigenin and PLX4032, administration of the PI3K inhibitor wortmannin further decreased the cell viability, and increased the percentage of dead cells. In conclusion, our results suggest that PLX4032 augments apigenin-induced cytotoxicity in ATC cells harboring BRAFV600E. Moreover, Akt suppression potentiates the combined effect of apigenin and PLX4032 in ATC cells harboring BRAFV600E.

Socioeconomic disparities of periodontitis in Koreans based on the KNHANES IV

OBJECTIVES

The aim of this study was to identify the socioeconomic factors associated with the prevalence of periodontitis in Koreans.

METHODS

Cross-sectional data from 12 763 subjects, 15 years old and above, who underwent periodontal examinations were obtained from the Korean National Health and Nutrition Examination Survey IV (2007-209). Multivariate linear and logistic regression analyses were applied to estimate the association between socioeconomic indicators and prevalence of periodontitis.

RESULTS

A significant association was found between increasing age and periodontitis. Participants with higher income were less likely to have periodontitis (aOR = 0.9 and 95% CI = 0.78-0.98, and aOR = 0.7 and 95% CI = 0.60-0.80 in the middle and highest quintiles of monthly household income, respectively). In addition, participants living in rural areas were less likely to have periodontitis (aOR = 0.9 and 95% CI = 0.81-0.99), and current smokers were more likely to have periodontitis (aOR = 1.7 and 95% CI = 1.49-1.89). The analysis of comorbidities revealed that individuals with diabetes mellitus (DM) were significantly more likely to have periodontitis (aOR = 1.4 and 95% CI = 1.18-1.68).

CONCLUSIONS

In a rapidly increasing Korean population, the lower socioeconomic groups as well as individuals with DM were significantly more likely to present with periodontitis.

(Micro)spectroscopic analyses of particle size dependence on arsenic distribution and speciation in mine wastes

The chemical speciation and distribution of potentially toxic metal(loid)s in mine wastes is critical to assessing the risks posed by these wastes and predicting the potential bioavailability of the metal(loid)s present. Of additional potential importance is the role of particle size in the fate, transport, and toxicity of contaminated mining materials. Spectroscopic analyses of size-separated mine tailings and adjacent background samples from the Randsburg Historic Mining District, California were conducted to quantify the speciation and distribution of arsenic (As) as a function of particle size. Micro-X-ray fluorescence (μXRF) mapping of separate size fractions was used to identify multiple populations of particles with different As:Fe ratios, indicating a variety of distinct arsenic-bearing species. Bulk extended X-ray absorption fine structure (EXAFS) spectroscopy identified phases including arseniosiderite, Ca2Fe3(3+)(AsO4)3O3·3H2O, and As(V) sorbed to iron hydroxides (ferrihydrite, goethite), confirming a strong statistical correlation between arsenic and iron observed in both μXRF studies and bulk chemical analyses. Differences in As speciation between the mine tailings and background samples also suggest that weathering of crystalline As-bearing phases in tailings leads to sorption of dissolved arsenic to iron hydroxides in nontailings background material.

Inhibition of p21 and Akt potentiates SU6656-induced caspase-independent cell death in FRO anaplastic thyroid carcinoma cells

SU6656 is a small-molecule indolinone that selectively inhibits Src family kinase and induces death of cancer cells. The aim of the present study was to investigate the influence of SU6656 on cell survival and to assess the role of p21 and PI3K/Akt signaling in cell survival resulting from SU6656 treatment in anaplastic thyroid carcinoma (ATC) cells. When 8505C, CAL62, and FRO ATC cells were treated with SU6656, the viability of 8505C and CAL62 ATC cells decreased only after treatment with SU6656 at a dosage of 100 μM for 72 h, while the viability of FRO ATC cells decreased after treatment with SU6656 in a concentration- and time-dependent manner. Cell viability was not changed by pretreatment with the broad-spectrum caspase inhibitor z-VAD-fmk. Phospho-Src protein levels were reduced, and p21 protein levels were elevated. Phospho-ERK1/2 protein levels were multiplied without alteration of total ERK1/2, total Akt, and phospho-Akt protein levels. Regarding FRO ATC cells, the decrement of cell viability, the increment of cleaved PARP-1 protein levels, and the decrement of phospho-Src protein levels were shown in p21 siRNA- or LY294002-pretreated cells compared to SU6656-treated control cells. ERK1/2 siRNA transfection did not affect cell viability and protein levels of cleaved PARP-1, p21, and Akt. In conclusion, these results suggest that SU6656 induces caspase-independent death of FRO ATC cells by overcoming the resistance mechanism involving p21 and Akt. Suppression of p21 and Akt enhances the cytotoxic effect of SU6656 in FRO ATC cells.

A retrospective study of clinical outcomes of α-blocker or finasteride monotherapy followed by combination therapy: determination of the period of combination therapy of α-blocker and finasteride

AIMS

We investigated outcomes after discontinuing alpha-blockers or finasteride in patients who initially received combination therapy and compared differences by duration of combination therapy.

METHODS

Patients with international prostate symptom score ≥ 8, serum prostatic-specific antigen (PSA) < 4 ng/ml, prostate volume > 25 cm(3) and combination therapy of alpha-blockers and finasteride for more than 6 months were classified into three groups. Group 1 continued combination therapy; group 2, alpha-blockers monotherapy; and group 3, finasteride monotherapy. All parameters were evaluated before and after changing to monotherapy. Patients who received combination therapy for 6-9 months and those who received combination therapy for longer were comparatively analysed.

RESULTS

Mean age of the 106 patients was 66.9 ± 7.8 years. No significant differences in baseline symptom scores, PSA or prostate volume were found. Following combination therapy, symptom scores, and quality of life (QoL) decreased for all groups. Group 1 maintained decreased PSA and prostate volume, and improved uroflowmetric profiles. No differences in uroflowmetric parameters were found after 6 months. Group 2 maintained improved symptoms, QoL and uroflowmetric profiles, although PSA and prostate volume returned to baseline. Group 3 maintained lowered PSA and prostate volume, whereas Qmax returned to baseline. QoL scores showed no change. Patients who received combination therapy for ≥9 months improved more in symptoms and QoL than those who received shorter combination therapy.

CONCLUSIONS

Discontinuation of alpha-blockers or finasteride after combination therapy for ≥ 6 months maintained improvements in symptoms. The appropriate period of combination therapy was ≥ 9 months.

CCAAT/Enhancer-binding protein-homologous protein sensitizes to SU5416 by modulating p21 and PI3K/Akt signal pathway in FRO anaplastic thyroid carcinoma cells

SU5416, vascular endothelial cell growth factor receptor inhibitor, suppresses hypoxia-induced angiogenesis, growth, proliferation, and metastasis in cancer cells. CCAAT/enhancer-binding protein-homologous protein (CHOP) has pivotal roles in regulation of growth and survival. In the present study, we evaluated the effects of SU5416 on cell survival, p21, and PI3K/Akt signal pathway in FRO anaplastic thyroid carcinoma (ATC) cells. Moreover, we investigated the roles of CHOP in cell survival under condition of SU5416 treatment in FRO ATC cells. After SU5416 treatment, cell viability, PARP-1, and caspase-3 protein levels were not changed. p53 and p27 protein levels decreased while p21 protein levels increased. Phospho-Akt protein levels were not altered. In SU5416-treated situation, cell viability was not different before and after administration of either p21 siRNA or LY294002 whereas it was lessened after co-administration of p21 siRNA and LY294002. Compared to SU5416 treatment alone, cell viability was reduced with CHOP plasmid but it was unchanged with CHOP siRNA. PARP-1 and caspase-3 protein levels with CHOP plasmid were elevated whereas the protein levels with CHOP siRNA were similar. While CHOP plasmid transfection diminished p21 and phospho-Akt protein levels, CHOP siRNA transfection did not alter the protein levels. In conclusion, these results suggest that CHOP may sensitize FRO ATC cells to SU5416 thereby inhibiting cell survival by modulating p21 and PI3K/Akt signal pathway. Furthermore, these findings imply that CHOP may be a possible candidate as the chemosensitizing factor for induction of cytotoxicity in ATC cells exposed to SU5416.

Diagnostic efficacy of gadoxetic acid-enhanced MRI for the detection and characterisation of liver metastases: comparison with multidetector-row CT

OBJECTIVES

We compared the diagnostic performance of gadoxetic acid-enhanced MRI and 16-slice multidetector CT (MDCT) with respect to their abilities to detect hepatic metastases and differentiate hepatic metastases from hepatic cysts and haemangiomas.

METHODS

67 patients with 110 liver metastases (size 0.3-2.5 cm), 33 haemangiomas (size 0.5-1.5 cm) and 17 cysts (size 0.3-1.0 cm) underwent 4-phase MDCT and gadoxetic acid-enhanced MRI, including early dynamic phases, post-contrast T(2) weighted turbo spin echo sequences and 20 min hepatocyte-selective phases. Two observers independently analysed each image in random order. Sensitivity and diagnostic accuracy for lesion detection and differentiation for MDCT and gadoxetic acid-enhanced MRI were calculated using receiver operating characteristic analysis.

RESULTS

For both observers, the Az values of gadoxetic acid-enhanced MRI (mean, 0.982 and 0.981) were significantly higher than the Az values of MDCT (mean, 0.839 and 0.892) (p<0.05) for the detection of metastases and for the differentiation of metastases from haemangiomas and cysts. Sensitivities of gadoxetic acid-enhanced MRI with regard to the detection and characterisation of liver metastases (mean, 96.9% and 96.0%) were significantly higher than those of MDCT (mean, 78.7% and 75.0%) (p<0.05).

CONCLUSION

Gadoxetic acid-enhanced MRI showed higher diagnostic accuracy and sensitivity than did MDCT for the detection of hepatic metastases and for the differentiation between hepatic metastases and hepatic haemangiomas or cysts.

Effects of pregabalin on the activity of glutamate transporter type 3

BACKGROUND

Pregabalin, (S)-3-aminomethyl-5-methyl hexanoic acid, is a ligand for the α2δ subunit (a component of voltage-gated calcium channels) and has analgesic and anticonvulsant properties. Glutamate uptake by glutamate transporters may be a mechanism for these properties. We investigated the effects of pregabalin on the activity of the neuronal glutamate transporter type 3 (EAAT3).

METHODS

EAAT3 was expressed in Xenopus laevis oocytes. Two-electrode voltage clamping was used to record membrane currents before, during, and after applying l-glutamate (30 μM) in the presence or absence of pregabalin. Currents were also measured in oocytes pretreated with a protein kinase C (PKC) activator (phorbol-12-myristate-13-acetate, PMA), PKC inhibitors (chelerythrine or staurosporine), or a phosphatidylinositol-3-kinase (PI3K) inhibitor wortmannin.

RESULTS

The exposure of the oocytes injected with EAAT3 mRNA to serial concentrations of pregabalin (0.06-60 μM) significantly increased their responses to 30 μM l-glutamate. A kinetic study showed that pregabalin significantly increased V(max) without changing K(m). Treatment of oocytes with PMA, pregabalin, or pregabalin plus PMA significantly increased transporter currents vs controls, but treatment with PMA plus pregabalin did not increase the responses further vs PMA or pregabalin alone. In addition, pretreatment of oocytes with two PKC inhibitors (chelerythrine or staurosporine), or inhibitor wortmannin, significantly reduced basal and pregabalin-enhanced EAAT3 activity.

CONCLUSIONS

Pregabalin increased EAAT3 activity and PKC and PI3K were involved. This may explain the analgesic effect of pregabalin in neuropathic pain.

Combination of propofol and remifentanil target-controlled infusion for laryngeal mask airway insertion in children

BACKGROUND

The addition of remifentanil to propofol administration can improve the conditions for insertion of laryngeal mask airways (LMAs). However, the extent to which remifentanil reduces propofol requirements when both drugs are administered concomitantly via target-controlled infusion (TCI) in pediatric patients has not been adequately demonstrated. The purpose of this study was to determine the target concentration of propofol that is required for LMA insertion at three different remifentanil target concentrations (0, 2.5, and 5 ng kg(-1) min(-1)) during TCI in children.

METHODS

A total of 67 children, aged 2 to 12 years, were included, and anesthesia was conducted with TCI of propofol and remifentanil using the STELPUMP program. The children were assigned to three groups in a randomized, double-blind manner: propofol with saline (control group), propofol with 2.5 ng mL(-1) of remifentanil (low-remifentanil group), and propofol with 5.0 ng ml(-1) of remifentanil (high-remifentanil group). The EC(50) of propofol for LMA insertion at each target-concentration of remifentanil was determined using Dixon's up-and-down method, and the EC(50) of propofol in each group was compared using the Kruskal-Wallis ANOVA by rank test.

RESULTS

The EC(50) for propofol was 5.18 mcg mL(-1) in the control group, 4.81 mcg ml(-1) in the low-remifentanil group, and 4.36 mcg mL(-1) in the high-remifentanil group, which was significantly different between the control group and the high-remifentanil group only (P<0.001).

CONCLUSION

A higher target concentration of remifentanil significantly reduced the propofol target concentration for LMA insertion during TCI of both drugs in children, but low concentrations of remifentanil failed to reduce the propofol requirement.

Alpha-lipoic acid inhibits endoplasmic reticulum stress-induced cell death through PI3K/Akt signaling pathway in FRTL5 thyroid cells

Alpha-lipoic acid (ALA) has been shown to modulate cell death via PI3K/Akt signal pathway in various cells. In the present study, the effects of ALA on cell death and PI3K/Akt signal pathway linked to cell death-related proteins during endoplasmic reticulum (ER) stress in FRTL5 thyroid cells were evaluated. In FRTL5 thyroid cells, cell viability increased by ALA pretreatment in tunicamycin (TN)-treated cells. When TN was treated, CCAAT/enhancer-binding protein-homologous protein (CHOP) and Bax protein levels were elevated while Bcl-2 protein levels were reduced. ALA diminished CHOP and Bax protein levels, and augmented Bcl-2 protein levels in TN-treated cells. After exposure to TN, phospho-Akt protein levels were repressed whereas total Akt protein levels were not changed. ALA increased phospho-Akt protein levels but not total Akt protein levels in both non-TN-treated and TN-treated cells. After LY294002 administration in non-TN-treated cells, cell viability was reduced, and CHOP and Bax protein levels were elevated, and Bcl-2 protein levels were reduced. The CHOP, Bcl-2 and Bax protein levels were not different after LY294002 administration in TN-treated cells. LY294002 and wortmannin decreased cell viability, and increased CHOP and Bax protein levels, and decreased Bcl-2 protein levels in ALA-pretreated and TN-treated cells. In conclusion, these results suggest that ER stress may induce cell death by modulating PI3K/Akt signal pathway linked to cell death-related proteins in FRTL5 thyroid cells. Moreover, these findings imply that ALA may ameliorate ER stress-induced cell death by activating PI3K/Akt signal pathway and attenuating changes of cell death-related proteins in FRTL5 thyroid cells.

Effects of all-trans retinoic acid on sodium/iodide symporter and CCAAT/enhancer-binding protein-homologous protein under condition of endoplasmic reticulum stress in FRTL5 thyroid cells

In thyroid cells, the effects of all- TRANS retinoic acid (ATRA) on sodium/iodide symporter (NIS) and CCAAT/enhancer-binding protein-homologous protein (CHOP) under condition of endoplasmic reticulum (ER) stress have not been evaluated. In the present study, the relationships between NIS, CHOP, and p38 MAPK, and the effects of ATRA on NIS and CHOP expression as well as on p38 MAPK activation under condition of ER stress in thyroid cells were investigated. In FRTL5 thyroid cells, NIS mRNA and protein levels decreased following tunicamycin (TN) treatment, while CHOP mRNA and protein levels increased. In addition, while CHOP mRNA levels decreased after administration of tauro-UDCA and siCHOP, NIS mRNA levels were not altered. After pretreatment with SB203580, NIS mRNA levels decreased in non-TN-treated cells but increased in TN-treated cells. In contrast, CHOP mRNA levels decreased in both non-TN-treated and TN-treated cells. Exposure to ATRA decreased NIS mRNA levels in non-TN-treated cells but increased NIS mRNA levels in TN-treated cells. ATRA decreased CHOP mRNA levels in both non-TN-treated and TN-treated cells although the response was significant only in TN-treated cells. Phospho-p38 MAPK protein levels but not total p38 MAPK protein levels increased in TN-treated cells. ATRA attenuated this increase in phopho-p38 MAPK protein levels. In conclusion, our results demonstrate that ER stress may induce reciprocal changes in NIS and CHOP expression via p38 MAPK in FRTL5 thyroid cells, and that ATRA may attenuate ER stress-induced alterations in NIS and CHOP expression by modulating the phosphorylation of p38 MAPK in FRTL5 thyroid cells.

A room-temperature semiconductor spaser operating near 1.5 μm

Room temperature spasing of surface plasmon polaritons at 1.46 μm wavelength has been demonstrated by sandwiching a gold-film plasmonic waveguide between optically pumped InGaAs quantum-well gain media. The spaser exhibits gain narrowing, the expected transverse-magnetic polarization, and mirror feedback provided by cleaved facets in a 1-mm long cavity fabricated with a flip-chip approach. The 1.06-μm pump-threshold of ~60 kW/cm2 is in good agreement with calculations. The architecture is readily adaptable to all-electrical operation on an integrated microchip.

Effect of remifentanil on arterial oxygenation during one-lung ventilation

This study was designed to assess the dose-related effects of remifentanil on arterial oxygenation during one-lung ventilation (OLV) under total intravenous anaesthesia with propofol. A total of 104 patients scheduled for elective lung resection surgery requiring OLV were randomly assigned to one of four groups with a target effect-site concentration (Ce) of remifentanil of 0.5, 1, 2 or 4 ng/ml. Patients were anaesthetized with propofol and remifentanil in 100% oxygen. Arterial blood gas analysis was performed after 15 min of two-lung ventilation (TLV15, baseline) and after 15 and 30 min of OLV (OLV15 and OLV30). Mean arterial oxygen tension (PaO2) decreased significantly at OLV15 and OLV30 compared with baseline in all groups, but was comparable in the four groups at each time point, suggesting that remifentanil infusion with a Ce < or =4 ng/ml can be successfully used for anaesthesia with propofol during OLV in lung surgery without any significant changes in PaO2.

Autonomic changes in preoperative uncomplicated diabetic patients with postural changes

Diabetic autonomic neuropathy is a critical complication frequently encountered in anaesthetic and surgical practice. Power spectral analysis is a noninvasive tool for monitoring frequency analysis of heart rate variability (HRV) and autonomic control of the heart. This study examined HRV changes in preoperative diabetic patients without overt signs of autonomic dysfunction and in matched controls (n=18 per group). HRV values at -15 degrees, 0 degrees, 15 degrees, 45 degrees and sitting positions were compared between groups and for each position. HRV in diabetic patients was lower than in controls at all positions (absolute units). Low-frequency power (normalized units) and the low-frequency/high-frequency ratio increased significantly at 45 degrees and in sitting positions in controls but not in diabetic patients. Pre-existing autonomic derangements in diabetic patients without overt clinical symptoms can be aggravated by high-degree tilting or sitting positions. Consequently, great care should be taken during the intra- and perioperative management of these patients.

A short period of inhalation induction with sevoflurane prevents rocuronium-induced withdrawal in children

BACKGROUND

the aim of this study was to determine whether or not inhalation induction with sevoflurane can prevent the withdrawal movement associated with the injection of rocuronium.

METHODS

a total of 75 pediatric patients were randomly allocated to five groups (S 1.5, 2.0, 2.5, 3.0, and the control group). In the control group (n=15), 2.5% thiopental 5 mg/kg was injected intravenously. Rocuronium 0.4 mg/kg was injected immediately after loss of consciousness. In the S 1.5, 2.0, 2.5, or 3.0 group, rocuronium 0.4 mg/kg was injected at 1.5, 2, 2.5, or 3 min after inhalation induction, respectively, and the withdrawal response was recorded. End-tidal sevoflurane concentrations were recorded at the time of the rocuronium injection. The inhalation time of sevoflurane before rocuronium injection required to provide no withdrawal response in 50% and 95% of patients (IT(50) and IT(95) ) was calculated.

RESULTS

the incidence of withdrawal was 80% (12/15), 71.4% (10/14), 21% (3/14), 0% (0/14), and 0% (0/15) in group C, group S 1.5, group S 2.0, group S 2.5, and group S 3.0, respectively. IT(50) of the rocuronium injection time was 1.7 min (95% CI: 1.5-1.9) and IT(95) was 2.3 min (95% CI: 2.0- 2.9).

CONCLUSIONS

this study demonstrated that inhalation induction with sevoflurane can prevent the withdrawal movement induced by rocuronium in children, and IT(50) and IT(95) for the prevention of movement was 1.7 and 2.3 min, respectively.

Estimation of relative defect densities in InGaN laser diodes by induced absorption of photoexcited carriers

Defects are one of the most important factors influencing the optical properties of groups III-V nitride semiconductor materials and thereby their applicability to light-emitting diodes. In this paper, we demonstrate that it is possible to estimate the presence of defects in InGaN laser diodes by performing pump-probe measurements and observing the induced absorptions. We have confirmed that the induced absorption originates from defects by performing experiments in which the pump intensity is varied. We believe that our method provides a powerful tool for evaluating the optical quality of InGaN materials before processing them into device fabrications.

Assessment of radiation dose for surrounding organs and persons approaching implanted patients upon brachytherapy of prostate cancer with Iridium-192

To assess a proper dose for radiation therapy fitting the typical physical characteristics of male Korean bodies, a mathematical phantom was prepared based on standard Korean male measurements. Upon brachytherapy of prostate cancer by implanting 192Ir into the prostate gland (the source organ), the absorbed dose of the prostate gland and surrounding organs and the expected dose of people within the vicinity were assessed. 192Ir, which has been the radionuclide of choice for prostate cancer brachytherapy, was selected for the simulation. It was assumed that 1 Ci of initial radioactivity would be administered. As a result, 1.28E-02 Gy/Ci was exhibited in the prostate gland of the source organ, and the dose to which persons within the vicinity were exposed was exhibited to be 9.19E-06 Sv at a distance of 30 cm from the front.

Diagnostic efficacy of gadoxetic acid-enhanced MRI in the detection of hepatocellular carcinomas: comparison with gadopentetate dimeglumine

This study compared the efficacy of gadoxetic acid-enhanced MRI and gadopentetate dimeglumine-enhanced MRI in the detection of small hepatocellular carcinoma (HCC). Both MRI techniques were performed on 43 patients with a total of 59 HCCs (size range, 0.5-2.0 cm), with a mean interval between the two MRI studies of 3 days (range, 2-7 days). Two observers reviewed both data sets in consensus. Diagnostic accuracy and sensitivity were evaluated using the alternative-free response receiver operator characteristic (ROC) method. The gadoxetic acid set showed a trend toward increased area under the ROC curve (Az value = 0.958) compared with the gadopentetate dimeglumine set (Az value = 0.927), but the difference was not significant (p = 0.362). The sensitivity of the gadoxetic acid set (n = 51, 86.4%) was significantly higher than that of the gadopentetate dimeglumine set (n = 38, 64.4%) (p = 0.0001). Gadoxetic acid-enhanced MRI is a more sensitive diagnostic tool for detection of HCC than gadopentetate dimeglumine-enhanced MRI.

An integrated surface-plasmon source

A compact and versatile source of coherent surface-plasmon polaritions (SPPs) is demonstrated by end-coupling a laser diode operating at 1.46 microm to a plasmonic waveguide integrated on the same microchip. With an optimized overlap between the spatial-modes of the laser and a planar-stripe waveguide, a high coupling efficiency of approximately 36% is achieved, that computations show could approach approximately 60% with smaller, readily achievable gaps between laser and waveguide. This integrated and electrically-activated source, with an available SPP power limited only by the laser diode, appears ideally suited for directly driving plasmonic circuitry or surface-enhanced sensors.