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.

Taxonomic study of amanita subgenus lepidella and three unrecorded amanita species in Korea

Amanita Pers. is a well-known monophyletic mushroom genus with a broad distribution. However, the diversity of Korean Amanita species has been underestimated, and most taxonomic studies conducted in Korea have only investigated their morphological characteristics. This approach is frequently insufficient for correct identification in fungal classification; therefore, we constructed a phylogeny of Amanita subgen. Lepidella in order to understand the phylogenetic placements of 16 Amanita specimens collected in Korea in 2012. The phylogeny constructed using the sequence data of the internal transcribed spacers and the partial large subunit of ribosomal RNA identified nine Amanita species (A. citrina, A. excelsa var. spissa, A. flavipes, A. fritillaria, A. oberwinklerana, A. pallidorosea, A. rubescens, A. subjunquillea, and A. volvata); of these, A. fritillaria, A. oberwinklerana, and A. pallidorosea are new to Korea.

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.

Two novel Talaromyces species isolated from medicinal crops in Korea

Two novel biverticillate Talaromyces species, T. angelicus and T. cnidii, were collected from the medicinal crops Angelica gigas and Cnidium officinale, respectively, in Korea. Phylogenetic analyses with the nuclear ribosomal internal transcribed spacer (ITS) region and the β-tubulin gene as well as morphological analyses revealed that the two species differ from any known Talaromyces species. Talaromyces angelicus is related to T. flavovirens in the phylogeny of the ITS region, but the new species is grouped together with Penicillium liani and T. pinophilus in terms of its β-tubulin phylogeny, and its growth rate on Czapek yeast autolysate differs from that of T. flavovirens. Talaromyces cnidii is phylogenetically similar to T. siamensis, but exhibits differences in the morphologies of the colony margin, metulae, and conidia.

Four Newly Recorded Amanita Species in Korea: Amanita sect. Amanita and sect. Vaginatae

We collected nearly 70 specimens of Amanita species during a diversity study of Korean mushrooms conducted in 2012. In this study, we primarily investigated 23 Amanita specimens belonging to sections Amanita and Vaginatae. Based on sequence data of the internal transcribed spacers and partial large subunit of ribosomal RNA and morphological characteristics, we identified the following 15 phylogenetic species: A. alboflavescens, A. ceciliae, A. farinosa, A. fulva, A. griseofolia, A. ibotengutake, A. melleiceps, A. orientifulva, A. pantherina, A. rubrovolvata, A. sinensis, A. subglobosa, A. vaginata, A. cf. vaginata f. alba, and an undescribed Amanita species. In this study, four of the identified Amanita species (A. griseofolia, A. ibotengutake, A. orientifulva, and A. sinensis) were reported for the first time in Korea.

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.

Trichoderma mienum sp. nov., isolated from mushroom farms in Japan

During an investigation of Hypocrea/Trichoderma species inhabiting mushroom bedlogs, we found five strains of an undescribed species from a culture collection. These were analyzed using a combined approach, including morphology of holomorph, cultural studies, and phylogenetic analyses of the rRNA gene cluster of the internal transcribed spacer region, translation elongation factor 1-α, and RNA polymerase subunit II gene sequences. Distinctive morphological characters include stromata with green ascospores produced on potato dextrose agar medium, and Gliocladium-like to irregularly Verticillium-like conidiophores. In phylogenetic analyses, this species belongs to the Semiorbis clade, but its morphological characteristics do not match the other members of this clade. Based on morphological observations and phylogenetic analyses, we describe this as a new species, Trichoderma mienum, representing its Hypocrea teleomorph and Trichoderma anamorph.

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.

First Report of Foliar Blight on Dendropanax morbifera Caused by Alternaria panax

Leaf spot and blight disease was observed on two-year-old seedlings of Dendropanax morbifera (Korean name: Hwangchil tree) during July of 2008 in Jindo Island, Korea. Symptoms included yellow-brown to dark brown irregularly enlarged spots frequently located along the veins of leaves. The lesions were often surrounded by chlorotic haloes. Severe leaf blight and subsequent defoliation occurred when conditions favored disease outbreak. The causal organism of the disease was identified as Alternaria panax based on morphological characteristics and sequence analysis of the internal transcribed spacer region of rDNA. A. panax isolates induced leaf spots and blight symptoms not only on D. morbifera but also on the other members of Araliaceae tested. This is the first report of foliar blight caused by A. panax on D. morbifera.