New monoterpene glycosides and phenolic compounds from Distylium racemosum and their inhibitory activity against ribonuclease H

Two new monoterpene glycosides, distyloside A-B (1-2), and a new megastigmane glucoside, iso-dihydrodendranthemoside A (3) were isolated from twigs and leaves of Distylium racemosum, along with five known phenolic compounds (4-8). The structures were established via spectroscopic techniques and chemical transformations, and the absolute stereochemistry of 3 was determined by Mosher's esterification. A homogeneous fluorescence resonance energy transfer (FRET) quenching assay was used to determine the inhibitory activity of isolates (1-8) on the ribonuclease H enzymes from HIV-1, 2, human, and Escherichia coli. Among them, 6″-O-galloylsalidroside (6) showed potent inhibitory effects with an IC(50) value of 3.5 μM on HIV-2, and 1.7 μM on human RNase H, respectively.

Protective effect of components isolated from Lindera erythrocarpa against oxidative stress-induced apoptosis of H9c2 cardiomyocytes

Eight compounds were isolated from the methanol fraction of Lindera erythrocarpa and assessed for their ability to protect H9c2 cardiomyocytes against oxidative stress-induced cell death. Three of the compounds significantly reduced the release of lactate dehydrogenase from H9c2 cardiomyocytes treated with buthionine-[S,R]-sulfoximine and reduced the uptake of propidium iodide by these cells. These effects were concentration-dependent. The three inhibitory compounds were identified as (-)-epicatechin, avicularin and quercitrin by spectroscopic techniques including one- and two-dimensional NMR and mass spectroscopy.

Phenylpropanoids from the leaves of Acanthopanax koreanum and their antioxidant activity

By various chromatographic methods, one new phenylpropanoid, acanthopanic acid (1), and three known compounds, 1,2-O-dicaffeoylcyclopenta-3-ol (2), (4S)-α-terpineol 8-O-β-D-glucopyranoside (3), and rutin (4), were isolated from the methanol extract of the Acanthopanax koreanum leaves. Their structures were elucidated on the basis of spectroscopic analyses, and their antioxidant activities were evaluated by the intracellular reactive oxygen species (ROS) radical scavenging 2',7'-dichlorofluorescein diacetate assay. Among them, compounds 1, 2, and 4 showed significant scavenging capacity with IC(50) values of 3.8, 2.6, and 2.9 μM, respectively, and compound 3 showed weak scavenging capacity with the inhibition rate of 37% at 40 μM.

A case of bilateral ovarian synchronous tumors (left ovarian serous papillary adenocarcinoma and right ovarian malignant mixed Müllerian tumor)

Synchronous bilateral ovarian cancer is extremely rare and there is no established guideline for management. A case of a 58-year-old multiparous woman with bilateral ovarian synchronous malignant tumors is presented. The clinical consideration and treatment of related cases are discussed.

A multicenter, randomized, placebo-controlled, double-blind phase II trial evaluating the optimal dose, efficacy and safety of LC 15-0444 in patients with type 2 diabetes

AIM

The objective of this study was to evaluate the optimal dose, efficacy and safety of a novel dipeptidyl peptidase-4 (DPP-IV) inhibitor, LC15-0444, in Korean subjects with type 2 diabetes mellitus treated by diet and exercise.

METHODS

This study was a double-blind, randomized, multicenter and parallel-group, dose-range finding study. We enrolled 145 patients (91 men and 54 women) with a median age of 53 years and a median body mass index of 25.1 kg/m(2) . The median baseline fasting plasma glucose (FPG) was 8.1 mmol/l, the median HbA1c was 7.9% and the median time since the diagnosis of diabetes was 3 years. After 2 weeks of an exercise/diet programme followed by 2 weeks of a placebo period, the subjects were randomized to one of the four following groups for a 12-week active treatment period: placebo and 50, 100 or 200 mg of LC15-0444.

RESULTS

All three doses of LC15-0444 significantly reduced the HbA1c from baseline compared to the placebo group (-0.06 vs. -0.98, -0.74 and -0.78% in the placebo and 50, 100 and 200 mg groups, respectively), without a significant difference between the doses. Subjects with a higher baseline HbA1c (≥8.5%) had a greater reduction in HbA1c. Insulin secretory function, as assessed using homeostasis model assessment-beta cell, C-peptide and the insulinogenic index, improved significantly with LC15-0444 treatment. Insulin sensitivity, as assessed using homeostasis model assessment-insulin resistance, also improved significantly after 12 weeks of treatment. The 50 and 200 mg groups had significantly reduced total cholesterol and low-density lipoprotein cholesterol levels at 12 weeks compared to the placebo group. No dosage of LC15-0444 affected weight or waist circumference. The incidences of adverse events were similar in all study subjects.

CONCLUSIONS

LC15-0444 monotherapy (50 mg for 12 weeks) improved the HbA1c, FPG level, oral glucose tolerance test results, β-cell function and insulin sensitivity measures, and was well tolerated in Korean subjects with type 2 diabetes.

Inactivation of Pseudomonas aeruginosa PA01 biofilms by hyperthermia using superparamagnetic nanoparticles

The primary goal of this study was to develop a new strategy to inactivate bacterial biofilms using the thermal stress derived from superparamagnetic iron oxide nanoparticles (SPIONs) in an alternating current (AC) magnetic field. A large number of studies have examined the inactivation of bacterial biofilms using antimicrobial agents; however, there have been no attempts to inactivate biofilms by hyperthermia using SPIONs. In this study, a SPION solution was added to Pseudomonas aeruginosa (P. aeruginosa) PA01 biofilm, and heat was generated by placing the nanoparticle-containing biofilm in an AC magnetic field. The heating temperature was dependent on the concentration of the added SPION solution. More than 4 log inactivation of the PA01 biofilm was obtained using a 60 mg mL(-1) SPION solution in 8 min, and this resulted in a dramatic disintegration of the bacterial cell membrane in the biofilm. This inactivation was largely due to the thermal effect. Local heating of a specific area is also possible using this method, and the heating temperature can be easily adjusted by controlling the concentration of the SPION solution. Therefore, hyperthermia using magnetic nanoparticles holds promise as an effective tool for inactivating the bacterial biofilm.

Lupane-type triterpenoids from the steamed leaves of Acanthopanax koreanum and their inhibitory effects on the LPS-stimulated pro-inflammatory cytokine production in bone marrow-derived dendritic cells

Two new compounds, (20R)-3α-hydroxy-29-dimethoxylupan-23,28-dioic acid (1) and 3α-hydroxylup-20(29)-ene-23,28-dioic acid 28-O-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl] ester (2), and eight known lupane-type triterpenoids (3-10), were isolated from steamed leaves of Acanthopanax koreanum. Chemical structures were determined using a combination of spectroscopic analyses and chemical reactivity. Compounds 1-10 were evaluated for their inhibitory activities on lipopolysaccharide (LPS)-stimulated interleukin (IL)-12 production in bone marrow-derived dendritic cells (BMDCs). Compound 1 exhibited inhibitory activity with IC(50) value of 26.5 μM on IL-12 production, compared with IC(50) value of 29.6 μM for the positive control. Compound 1 also showed significant suppression of LPS-stimulated IL-6 and tumor necrosis factor-alpha (TNF-α) production.

Superoxide is a potential culprit of caspase-3 dependent endothelial cell death induced by lysophosphatidylcholine

Oxidative stress in the vascular wall has intimately been implicated in the apoptosis of human umbilical vein endothelial cells (HUVECs) by lysophosphatidylcholine (LPC). However, the major type of reactive oxygen species (ROS) in this apoptotic signaling pathway remains to be clarified. In this study, we report that superoxide mediate LPC-induced caspase-3 dependent apoptosis in cultured HUVECs. The stimulation of HUVECs with LPC evoked apoptosis and ROS generation, and inhibited nitric oxide (NO) production in a dose-dependent manner. The classical caspase-3 dependent apoptosis was determined after 16 hours treatment by Western blotting using an antibody against cleaved caspase-3. The caspase-3 activation induced by LPC was prominently inhibited by antioxidants or NO donors and enhanced by NO inhibitors. Especially, LPC-induced caspase-3 activation was inhibited by superoxide dismutase (SOD) and enhanced by ammonium tetrathiomolybdate, SOD inhibitor. Additionally, xanthine/xanthine oxidase mixture increased the caspase-3 activation but catalase failed to reduce this superoxide-induced caspase-3 activation. These findings indicate that the superoxide generation caused by LPC activates the caspase-3 which results in HUVECs death. This study reveals some evidences linking superoxide with caspase-3 activation and provides a new dimension to superoxide-mediated caspase-3 activation in developing the endothelial dysfunction and atherosclerosis.

Microheater based on magnetic nanoparticle embedded PDMS

A microheater was established by embedding magnetic nanoparticles into PDMS (MNP-PDMS). MNP-PDMS generated heat under an AC magnetic field and the temperature was controlled by varying the magnetic particle content and the magnetic field intensity. In this study, the MNP-PDMS chip was demonstrated to amplify the target DNA (732 bp) with > 90% efficiency compared to the conventional PCR thermocycler, and exhibited good performance in regards to temperature control. This system holds great promise for reliably controlling the temperature of thermal processes on an integrated microchip platform for biochemical applications.

An anti-influenza component of the bark of Alnus japonica

This study to identify anti-influenza components of the bark of Alnus japonica resulted in the isolation of four lupane-type triterpenes (1-4) and one steroid (5). Their structures were characterized on the basis of physicochemical properties, NMR evidence, and ESI-MS data compared with reported data in the literature. Betulinic aldehyde (3) exhibited a particularly strong anti-influenza effect against KBNP-0028 relative to a positive control.

SP600125 suppresses Cdk1 and induces endoreplication directly from G2 phase, independent of JNK inhibition

Cell cycle controls ensure that DNA replication (S phase) follows mitosis resulting in two precise copies of the genome. A failure of the control mechanisms can result in multiple rounds of DNA replication without cell division. In endoreplication, cells with replicated genomes bypass mitosis, then replicate their DNA again, resulting in polyploidy. Endoreplication from G2 phase lacks all hallmarks of mitosis. Using synchronized cells, we show that the c-Jun N-terminal kinase (JNK) inhibitor, SP600125, prevents the entry of cells into mitosis and leads to endoreplication of DNA from G2 phase. We show that cells proceed from G2 phase to replicate their DNA in the absence of mitosis. This effect of SP600125 is independent of its suppression of JNK activity. Instead, the inhibitory effect of SP600125 on mitotic entry predominantly occurs upstream of Aurora A kinase and Polo-like kinase 1, resulting in a failure to remove the inhibitory phosphorylation of Cdk1. Importantly, our results directly show that the inhibition of Cdk1 activity and the persistence of Cdk2 activity in G2 cells induces endoreplication without mitosis. Furthermore, endoreplication from G2 phase is independent of p53 control.

A new norlupane triterpene from the leaves of Acanthopanax koreanum increases the differentiation of osteoblastic MC3T3-e1 cells

A new norlupane-triterpene, 3alpha,11alpha-dihydroxy-20,23-dioxo-30-norlupane-28-oic acid (1), and four known compounds; 3alpha,11alpha-dihydroxy-23-oxo-lup-20(29)-en-28-oic acid (2), 3alpha,11alpha-dihydroxylup-20(29)-en-28-oic acid (3), ent-kaur-16-en-19-oic acid (4), and betulabuside B (5) were isolated from the methanolic extract of the leaves of Acanthopanax koreanum. Their chemical structures were elucidated by mass, 1D- and 2D-NMR spectroscopy. To investigate the bioactivities of these compounds, their effects on the differentiation of osteoblastic MC3T3-E1 cells were tested. Compounds 3 and 4 significantly increased osteoblastic cell growth and differentiation as assessed by the MTT assay and collagen content, respectively (p < 0.05). Compounds 1 and 5 significantly increased the growth of MC3T3-E1 cells and caused a significant elevation of osteoblastic cell differentiation as assessed by the alkaline phosphatase activity. These results suggest that the compounds isolated from A. koreanum leaves have a direct stimulatory effect on bone formation in vitro and may contribute to the prevention for osteoporosis.

Comparison of desaturation and resaturation response times between transmission and reflectance pulse oximeters

BACKGROUND

In general, there is a response time between actual arterial hypoxemia and its detection by pulse oximeters. We compared the desaturation and resaturation response times between two types of pulse oximeters, transmission and reflectance pulse oximeters, to find out which oximeter has a more rapid response time.

METHODS

Thirty-three ASA 1 or 2 patients were enrolled in this study. A transmission pulse oximeter was placed on the index finger and a reflectance pulse oximeter was placed on the forehead and monitored simultaneously. After the induction of general anesthesia without pre-oxygenation, we waited until the oxygen saturation value of any of two pulse oximeters declined to 90%, and then mask ventilation was started with 100% oxygen. Oxygen saturation was recorded at an interval of 2 s during this time.

RESULTS

The desaturation response time of SpO(2) to 95% after apnea was 82.0 s (interquartile range: 67.0-98.5 s) vs. 94.0 s (interquartile range: 84.0-106.5 s) (P<0.001) and SpO(2) to 90% was 94.0 s (interquartile range: 75.5-109.5 s) vs. 100.0 s (interquartile range: 84.5-114.5 s) (P<0.001) in the reflectance and transmission oximeters, respectively. The resaturation response time from mask ventilation to 100% SpO(2) was 23.2+/-5.6 vs. 28.9+/-7.6 s (P<0.001) in the reflectance and transmission oximeters, respectively.

CONCLUSION

In clinical situations in which rapid changes in oxygen saturation are expected, we recommend the forehead reflectance pulse oximeter because it responds more quickly in detecting oxygen desaturation and resaturation compared with the transmission pulse oximeter.

Does propofol and alfentanil-induced sedation cause periodic apnoea in chronic renal failure patients?

AIMS

There is evidence suggesting that the respiratory response to sedation is different in patients with sleep apnoea, which is common in patients with chronic renal failure (CRF). This study examined the respiratory response of sedation with propofol and alfentanil, whose pharmacokinetics are not affected by the renal function, in CRF patients.

METHODS

Chronic renal failure patients who underwent arteriovenous-fistular surgery (CRF group) and patients who underwent chemoport insertion (control group) were enrolled in this study. Sedation was induced by infusing propofol 1.5 micro/ml and alfentanil 0.2 micro/kg/min continuously in both groups. In the desaturation study, the respiratory rate and peripheral oxygen saturation in room air were checked. In the apnoea-hypopnoea study, the patient's sedation (Observer's Assessment of Alertness/Sedation) score, apnoea-hypopnoea index (AHI) was recorded using a portable ventilation effort recorder (microMesam) while applying 5 l/min of oxygen through a facial mask.

RESULTS

The desaturation event was more common (21.5/h vs. 2/h, p = 0.001) in the CRF patients. Apnoea and hypopnoea (AHI: 13.0 vs. 1.6, p = 0.012, per cent of patients with an AHI > 5: 53.3% vs. 7.1%, p = 0.014) occurred more frequently in the CRF patients but the sedation score was not different.

CONCLUSION

Chronic renal failure patients have a higher risk of developing apnoea and hypopnoea during sedation, which highlights the need for careful monitoring and management in these patients.

Anti-influenza diarylheptanoids from the bark of Alnus japonica

This study to investigate anti-influenza components from the bark of Alnus japonica resulted in the isolation of two rare acylated diarylheptanoids, named oregonoyl A (5) and oregonoyl B (6), along with nine known compounds (1-4 and 7-11). Their structures were elucidated on the basis of extensive spectroscopic and chemical methods. Antiviral testing of compounds 1-11 against KBNP-0028 (H9N2) avian influenza virus showed that platyphyllone (10) was strongly active, and platyphyllonol-5-xylopyranoside (9) was moderately active against KBNP-0028 as compared with the positive control, zanamivir, respectively.

Inhibitors of osteoclast formation from rhizomes of Cibotium barometz

Eight compounds (1-8) were isolated from a methanol extract of Cibotium barometz rhizomes including two new furan derivatives, cibotiumbarosides A (1) and B (2), and a new glycoglycerolipid, cibotiglycerol (4). Their structures were elucidated by chemical and spectroscopic methods. Compounds 2-5 each showed inhibition of osteoclast formation with no affect on BMM cell viability.

Stimulation of large-conductance Ca2+-activated K+ channels by the Na+/Ca2+ exchanger inhibitor dichlorobenzamil in cultured human umbilical vein endothelial cells and mouse aortic smooth muscle cells

We investigated the effects of the selective inhibitor of Na(+)/Ca(2+) exchanger (NCX), 2',4'- and 3',4'-dichlorobenzamil (DCB), on large-conductance Ca(2+)-activated K(+) (BK(Ca)) channels in cultured human umbilical vein endothelial cells (HUVECs) and fresh isolated mouse aortic smooth muscle cells (MASMCs) using the patch clamp techniques. Both kinds of DCB reversibly activated BK(Ca) currents in whole-cell clamped HUVECs or MASMCs. The EC(50) of 2',4'-DCB for BK(Ca) current activation in HUVECs was 2.64 +/- 0.10 muM. In inside-out and outside-out patches, 2',4'-DCB remarkably increased BK(Ca) channels activity. 2',4'-DCB increased open frequency, but had no significant effect on mean open time. In inside-out patches, 2',4'-DCB shifted the relationship curve between [Ca(2+)](i) and open probability (NP(o)) to the left; the [Ca(2+)](i) required to evoke half-maximal activation changed from 1087.45 +/- 142.91 nM to 500.24 +/- 66.83 nM by 10 muM 2',4'-DCB. In addition, 2',4'-DCB shifted the relationship curve between membrane potential and NP(o) to the left; the membrane potential to evoke half-maximal activation changed from 81.1 +/- 2.4 to 64.7 +/- 3.1 mV by 10 muM 2',4'-DCB. 3',4'-DCB also increased BK(Ca) channels activity. There was no significant difference in the effect of DCB on BK(Ca) channels between both excised patches. These results suggested that 2',4'- and 3',4'-DCB activate BK(Ca) channels activity in HUVECs and MASMCs by increasing the sensitivity of BK(Ca) channels to cytosolic free Ca(2+) and membrane potential. Our report would provide a consideration if they are used as NCX blocker in vascular endothelial cells or smooth muscle cells.

Long-term survival in a patient with ruptured hepatocellular carcinoma

A 57-yr-old woman previously diagnosed with chronic hepatitis B was admitted via the emergency room because she suddenly developed epigastric pain with abdominal distension. On computed tomography (CT), a round enhancing mass was found on the left hepatic lobe with ascites in the peritoneal space. Bloody ascites were found upon tapping the ascites, and this led to the diagnosis of ruptured hepatocellular carcinoma (HCC). The patient was immediately treated with transcatheter arterial chemoembolization (TACE) including 50 mg of adriamycin and 10 mL of lipiodol, and then we performed left lateral segmentectomy 20 days later. To prevent recurrence of HCC by any micrometastasis, the patient subsequently received 8 cycles of adjuvant systemic chemotherapy (a regimen of epirubicin (50 mg/m(2)), cisplatin (60 mg/m(2)) and 5-fluorouracil (200 mg/m(2))) at monthly intervals. After this, the patient has been regularly followed up and she shows no signs of tumor recurrence 7 years later. This case suggests that surgical resection and subsequent adjuvant systemic chemotherapy with using an ECF regimen may provide long-term survival for patients ruptured HCC.

Improved purification process for cholera toxin and its application to the quantification of residual toxin in cholera vaccines

A simplified method for the purification of cholera toxin was developed. The 569B strain of Vibrio cholerae, a recognized hyper-producer of cholera toxin, was propagated in a bioreactor under conditions that promote the production of the toxin. The toxin was separated from the bacterial cells using 0.2-microm crossflow microfiltration, the clarified toxin was passed through the membrane into the permeate, and the bacterial cells were retained in the retentate. The 0.2-microm permeate was then concentrated 3-fold and diafiltered against 10 mM phosphate buffer, pH 7.6, using 30-kDa crossflow ultrafiltration. The concentrated toxin was loaded onto a cation exchange column, the toxin was bound to the column, and most of the impurities were passed unimpeded through the column. The toxin was eluted with a salt gradient of phosphate buffer, pH7.0, containing 1.0M NaCl. The peak containing the toxin was assayed for cholera toxin and protein and the purity was determined to be 92%. The toxin peak had a low endotoxin level of 3.1 EU/microg of toxin. The purified toxin was used to prepare antiserum against whole toxin, which was used in a G(M1) ganglioside-binding ELISA to determine residual levels of toxin in an oral inactivated whole-cell cholera vaccine. The G(M1) ganglioside-binding ELISA was shown to be very sensitive and capable of detecting as little as 1 ng/ml of cholera toxin.

Knowledge representation of critical laboratory results in using the SAGE framework and challenges to its implementation

When a laboratory result is abnormal, the Computerized Critical Laboratory Results Alerting System should notify clinicians promptly. Use of this system can decrease the length of time spent in life-threatening situations, the average length of stay and the cost. 10 criteria oriented not to the individual but to a large number of patients were defined, these criteria were encoded using the SAGE framework. This type of modeling is utilized to validate a knowledge converter that converts the SAGE output to a knowledge engine.

Clinical decision support service architecture for EHR perspectives in Korea

We present architecture for implementing independent, extensible, and interoperable clinical decision support service in perspective of EHR. In this architecture, components for implementing independent knowledge service and interface mechanism with EHR service or existing hospital information system are identified. With our architecture, new CDS services can be easily scalable since new knowledge module can added without changing knowledge infrastructure or other hospital information system.