Anesthesia choice and its potential impact on endoluminal functional lumen imaging probe measurements in esophageal motility disorders

BACKGROUND AND AIMS

The widespread use of peroral endoscopic myotomy (POEM) has revolutionized the management of esophageal motility disorders (EMDs). The introduction of an endoluminal functional lumen imaging probe (EndoFLIP, Medtronic, Dublin, Ireland) can serve as a complementary diagnostic tool to assess the mechanical properties (ie, pressure, diameter, distensibility, topography) of the esophagus. During EndoFLIP measurements, different anesthesia techniques may induce variable degrees of neuromuscular blockade, potentially affecting esophageal motility and altering the results of EndoFLIP metrics. The aim of this study was to compare the impact of using total intravenous anesthesia (TIVA) versus general anesthesia with inhalational anesthetics (GAIA) on diagnostic EndoFLIP measurements.

METHODS

This retrospective study included all adult patients (≥18 years) undergoing EndoFlip during the POEM procedure at our institution between February 2017 and February 2022. Differences in pressure, diameter, and distensibility index were obtained by using propofol-based TIVA versus sevoflurane-based GAIA with a 30 mL and a 60 mL balloon. The differences were divided into terciles and compared between diagnoses by using univariate comparisons and logistic regression models.

RESULTS

A total of 49 patients were included (39% type I achalasia, 43% type II or III achalasia, and 18% jackhammer esophagus [JE]). Compared with spastic disorders (types II and III achalasia and JE), type I had lower values of pressure differences at 60 mL in univariate (3.75 vs 15.20, P = .001) and multivariate (adjusted odds ratio, .89; 95% confidence interval, .82-.978) analyses. Compared with type I, types II and III achalasia had higher rates of pressure differences at 60 mL in the univariate (9.85 vs 3.75, P = .04) analysis and nearly reached significance in the multivariate analysis (1.09; 95% confidence interval, 1-1.20). Compared with type I achalasia, JE exhibited higher values in pressure differences at 60 mL (27.7 vs 3.75, P < .001).

CONCLUSIONS

Esophageal pressure, as measured by EndoFLIP, was significantly reduced when patients were sedated with sevoflurane-based GAIA. The use of sevoflurane-based GAIA for diagnostic EndoFLIP may potentially lead to the misclassification of spastic disorders as type I achalasia. Propofol-based TIVA should therefore be considered over sevoflurane-based GAIA for sedation during the diagnostic test.

The Impact of Race and Sex on the Clinical Outcomes of Homeless Patients With Alcoholic Liver Disease: Propensity Score Matched Analysis of US Hospitals

BACKGROUND

Among patients with alcoholic liver disease (ALD), homelessness poses significant medical and psychosocial risks; however, less is known about the effects of race and sex on the hospital outcomes of admitted homeless patients with ALD.

METHODS

The National Inpatient Sample database from 2012 to 2017 was used to isolate homeless patients with ALD, and the cohort was further stratified by race and sex for comparisons. Propensity score matching was utilized to minimize covariate confounding. The primary endpoints of this study include mortality, hospital length of stay, and hospital costs; secondary endpoints included the incidence of liver complications.

RESULTS

There were 3972 females/males postmatch, as well as 2224 Blacks/Whites and 4575 Hispanics/Whites postmatch. In multivariate, there were no significant differences observed in mortality rate, length of stay, and costs between sexes. Comparing liver outcomes, females had a higher incidence of hepatic encephalopathy [adjusted odds ratio (aOR) 1.02, 95% CI: 1.01-1.04, P<0.001]. In comparing Blacks versus Whites, Black patients had higher hospitalization costs (aOR 1.13, 95% CI: 1.03-1.24, P=0.01); however, there were no significant differences in mortality, length of stay, or liver complications. In comparing Hispanics versus Whites, Hispanic patients had longer length of hospital stay (aOR 1.12, 95% CI: 1.06-1.19, P<0.001), greater costs (aOR 1.15, 95% CI: 1.09-1.22, P<0.001), as well as higher prevalence of liver complications including varices (aOR 1.04, 95% CI: 1.02-1.06, P<0.001), hepatic encephalopathy (aOR 1.03, 95% CI: 1.02-1.04, P<0.001), and hepatorenal syndrome (aOR 1.01, 95% CI 1.00-1.01, P=0.03). However, there was no difference in mortality between White and Hispanic patients.

CONCLUSIONS

Black and Hispanic ALD patients experiencing homelessness were found to incur higher hospital charges; furthermore, Hispanic patients also had greater length of stay and higher incidence of liver-related complications compared with White counterparts.

The Trends in Health Care Utilization and Costs Associated With Primary Liver Cancer: An Analysis of United States Hospitals Between 2016 and 2019

BACKGROUND

Primary liver cancer (PLC) has placed an increasing economic and resource burden on the health care system of the United States. We attempted to quantify its epidemiology and associated costs using a national inpatient database.

METHODS

Hospital discharge and insurance claims data from the National Inpatient Sample were used to conduct this analysis. Patients diagnosed with PLC (hepatocellular carcinoma or cholangiocarcinoma) were included in the study population, which was then stratified using patient demographics, comorbidities, degree of cancer spread, liver disease complications, and other descriptors. Trends were analyzed via regression curves for each of these strata from the years 2016 to 2019, with special attention to patterns in hospitalization incidence, inpatient mortality rate, total costs, and average per-capita costs. The resulting curves were evaluated using goodness-of-fit statistics and P-values.

RESULTS

Aggregate hospitalization incidence, inpatient mortality rates, and total costs were found to significantly increase throughout the study period (P=0.002, 0.002, and 0.02, respectively). Relative to their demographic counterparts, males, White Americans, and those older than 65 years of age contributed the largest proportions of total costs. These population segments also experienced significant increases in total expenditure (P=0.04, 0.03, and 0.02, respectively). Admissions deemed to have multiple comorbidities were associated with progressively higher total costs throughout the study period (P=0.01). Of the categorized underlying liver diseases, only admissions diagnosed with alcoholic liver disease or nonalcoholic fatty liver disease saw significantly increasing total costs (P=0.006 and 0.01), although hepatitis C was found to be the largest contributor to total expenses.

CONCLUSIONS

From 2016 to 2019, total costs, admission incidence, and inpatient mortality rates associated with PLC hospitalization increased. Strata-specific findings may be reflective of demographic shifts in the PLC patient populations, as well as changes in underlying chronic liver disease etiologies.

Benefits of EUS-guided gastroenterostomy over surgical gastrojejunostomy in the palliation of malignant gastric outlet obstruction: a large multicenter experience

BACKGROUND AND AIMS

Palliation of malignant gastric outlet obstruction (mGOO) allows resumption of peroral intake. Although surgical gastrojejunostomy (SGJ) provides durable relief, it may be associated with a higher morbidity, interfere with chemotherapy, and require an optimum nutritional status. EUS-guided gastroenterostomy (EUS-GE) has emerged as a minimally invasive alternative. We aimed to conduct the largest comparative series to date between EUS-GE and SGJ for mGOO.

METHODS

This multicenter retrospective study included consecutive patients undergoing SGJ or EUS-GE at 6 centers. Primary outcomes included time to resumption of oral intake, length of stay (LOS), and mortality. Secondary outcomes included technical and clinical success, reintervention rates, adverse events (AEs), and resumption of chemotherapy.

RESULTS

A total of 310 patients were included (EUS-GE, n = 187; SGJ, n = 123). EUS-GE exhibited significantly lower time to resumption of oral intake (1.40 vs 4.06 days, P < .001), at lower albumin levels (2.95 vs 3.33 g/dL, P < .001), and a shorter LOS (5.31 vs 8.54 days, P < .001) compared with SGJ; there was no difference in mortality (48.1% vs 50.4%, P = .78). Technical (97.9% and 100%) and clinical (94.1% vs 94.3%) success was similar in the EUS-GE and SGJ groups, respectively. EUS-GE had lower rates of AEs (13.4% vs 33.3%, P < .001) but higher reintervention rates (15.5% vs 1.63%, P < .001). EUS-GE patients exhibited significantly lower interval time to resumption of chemotherapy (16.6 vs 37.8 days, P < .001). Outcomes between the EUS-GE and laparoscopic (n = 46) surgical approach showed that EUS-GE had shorter interval time to initiation/resumption of oral intake (3.49 vs 1.46 days, P < .001), decreased LOS (9 vs 5.31 days, P < .001), and a lower rate of AEs (11.9% vs 17.9%, P = .003).

CONCLUSIONS

This is the largest study to date showing that EUS-GE can be performed among nutritionally deficient patients without affecting the technical and clinical success compared with SGJ. EUS-GE is associated with fewer AEs while allowing earlier resumption of diet and chemotherapy.

The Impact of Malnutrition on the Hospital and Infectious Outcomes of Patients Admitted With Alcoholic Hepatitis: 2011 to 2017 Analysis of US Hospitals

GOALS

We specifically evaluate the effect of malnutrition on the infection risks of patients admitted with alcoholic hepatitis using a national registry of hospitalized patients in the United States.

BACKGROUND

Malnutrition is a common manifestation of alcoholic hepatitis that affects patient outcomes.

STUDY

2011 to 2017 National Inpatient Sample was used to isolated patients with alcoholic hepatitis, stratified using malnutrition (protein-calorie malnutrition, sarcopenia, and weight loss/cachexia) and matched using age, gender, and race with 1:1 nearest neighbor matching method. Endpoints included mortality and infectious endpoints.

RESULTS

After matching, there were 10,520 with malnutrition and 10,520 malnutrition-absent controls. Mortality was higher in the malnutrition cohort [5.02 vs. 2.29%, P<0.001, odds ratio (OR): 2.25, 95% confidence interval (CI): 1.93-2.63], as were sepsis (14.2 vs. 5.46, P<0.001, OR: 2.87, 95% CI: 2.60-3.18), pneumonia (10.9 vs. 4.63%, P<0.001, OR: 2.51, 95% CI: 2.25-2.81), urinary tract infection (14.8 vs. 9.01%, P<0.001, OR: 1.76, 95% CI: 1.61-1.91), cellulitis (3.17 vs. 2.18%, P<0.001, OR: 1.47, 95% CI: 1.24-1.74), cholangitis (0.52 vs. 0.20%, P<0.001, OR: 2.63, 95% CI: 1.59-4.35), and Clostridium difficile infection (1.67 vs. 0.91%, P<0.001, OR: 1.85, 95% CI: 1.44-2.37). In multivariate models, malnutrition was associated with mortality [P<0.001, adjusted odds ratio (aOR): 1.61, 95% CI: 1.37-1.90] and infectious endpoints: sepsis (P<0.001, aOR: 2.42, 95% CI: 2.18-2.69), pneumonia (P<0.001, aOR: 2.19, 95% CI: 1.96-2.46), urinary tract infection (P<0.001, aOR: 1.68, 95% CI: 1.53-1.84), cellulitis (P<0.001, aOR: 1.46, 95% CI: 1.22-1.74), cholangitis (P=0.002, aOR: 2.27, 95% CI: 1.36-3.80), and C. difficile infection (P<0.001, aOR: 1.89, 95% CI: 1.46-2.44).

CONCLUSION

This study shows the presence of malnutrition is an independent risk factor of mortality and local/systemic infections in patients admitted with alcoholic hepatitis.

The impact of frailty on the postoperative outcomes of patients undergoing cholecystectomy: propensity score matched analysis of 2011-2017 US hospitals

BACKGROUND

Frailty is an aggregate variable that encompasses debilitating geriatric conditions, which potentially affects postoperative outcomes. In this study, we evaluate the relationship between clinical frailty and post-cholecystectomy outcomes using a national registry of hospitalized patients.

METHODS

2011-2017 National Inpatient Sample database was used to identify patients who underwent cholecystectomy. Patients were stratified using the Johns Hopkins ACG frailty definition into binary (frailty and no-frailty) and tripartite frailty (frailty, prefrailty, no-frailty) indicators. The controls were matched to study cohort using 1:1 propensity score-matching and postoperative outcomes were compared.

RESULTS

Post-match, using the binary term, frail patients (n = 40,067) had higher rates of mortality (OR 2.07 95%CI 1.90-2.25), length of stay, costs, and complications. In multivariate, frailty was associated with higher mortality (aOR 2.06 95%CI 1.89-2.24). When using tripartite frailty term, prefrail (n = 35,595) and frail (n = 4472) patients had higher mortality (prefrailty: OR 2.04 95%CI 1.86-2.23; frailty: OR 2.49 95%CI 1.99-3.13), length of stay, costs, and complications. In multivariate, prefrailty and frailty were associated with higher mortality (prefrailty: aOR 2.02 95%CI 1.84-2.21; frailty: aOR 2.54 95%CI 2.02-3.19).

CONCLUSION

This study shows the presence of frailty (and prefrailty) is an independent risk factor of adverse postoperative outcomes in patients undergoing cholecystectomy.

The impact of cirrhosis on the postoperative outcomes of patients undergoing splenectomy: Propensity score matched analysis of the 2011-2017 US hospital database

BACKGROUND & OBJECTIVE

While splenectomy is performed for various trauma and non-trauma indications, there is little information about the impact of cirrhosis on the post-splenectomy outcomes, despite the intricate physiological and vascular connection between the liver and the spleen.

METHODS

2011-2017 National Inpatient Sample was used to select patient cases who underwent the splenectomy procedure, who were further stratified using cirrhosis. The cirrhosis-absent controls were matched to the study cohort using propensity score matching with nearest neighbor matching method. Endpoints included mortality, length of stay, hospitalization costs, and postoperative complications.

RESULTS

There were 675 patients with cirrhosis and 675 matched controls identified from the database. Cirrhosis cohort had higher mortality (20.0 vs 7.26%, p < 0.001, OR = 3.19, 95% CI = 2.26-4.52) and hospitalization costs ($210,716 vs $186,673, p = 0.003), but shorter length of stay (11.8 vs 12.5d, p = 0.04). In terms of complications, cirrhosis cohorts had higher postoperative bleeding (7.26 vs 4.3%, p = 0.027, OR = 1.74, 95% CI = 1.09-2.80) and shock (3.7 vs 1.04%, p = 0.002, OR = 3.67, 95% CI = 1.58-8.54), and were more likely to be discharged to short-term hospitals and home with home health care. On multivariate analysis, presence of cirrhosis resulted in higher mortality (p < 0.001, aOR = 3.30, 95% CI = 2.33-4.69).

CONCLUSIONS

Cirrhosis is an independent risk factor of postoperative mortality in patients undergoing splenectomy; given this finding, further precautious and multidisciplinary care should be rendered in these at-risk patients with cirrhosis in the setting of splenectomy.

The Clinical Impact of Cirrhosis on the Hospital Outcomes of Patients Admitted With Influenza Infection: Propensity Score Matched Analysis of 2011-2017 US Hospital Data

BACKGROUND/OBJECTIVES

Patients with cirrhosis have liver-related immune dysfunction that potentially predisposes the patients to increased influenza infection risk. Our study evaluates this cross-sectional relationship using a national registry of hospital patients.

METHODS

This study included the 2011-2017 National Inpatient Sample database. From this, respiratory influenza cases were isolated and stratified using the presence of cirrhosis into a cirrhosis-present study cohort and cirrhosis-absent controls; propensity score matching method was used to match the controls to the study cohort (cirrhosis-present) using a 1:1 matching ratio. The endpoints included mortality, length of stay, hospitalization costs, and influenza-related complications.

RESULTS

Following the match, there were 2,040 with cirrhosis and matched 2,040 without cirrhosis admitted with respiratory influenza infection. Compared to the controls, cirrhosis patients had higher in-hospital mortality (7.79 vs 3.43% p < 0.001, OR 2.38 95% CI 1.78-3.17), longer length of stay (7.25 vs 6.52 d p < 0.001), higher hospitalization costs ($70,009 vs $65,035 p < 0.001), and were more likely be discharged to a skilled nursing facility and home healthcare (vs routine home discharges). In terms of influenza-related complications, the cirrhosis cohort had higher rates of sepsis (29.8 vs 22% p < 0.001, OR 1.51 95% CI 1.31-1.74). In the multivariate regression analysis, cirrhosis was associated with higher mortality (p < 0.001, aOR 2.31 95% CI 1.59-3.35) and length of stay (p = 0.018, aOR 1.03 95% CI 1.01-1.06). In subgroup analysis of patients with decompensated (n = 597) versus compensated cirrhosis (n = 1443), those with decompensated cirrhosis had higher rates of in-hospital mortality (12.7 vs 5.75% p < 0.001, OR 2.39 95% CI 1.72-3.32), length of stay (8.85 vs 6.59 d p < 0.001), and hospitalization costs ($92,858 vs $60,556 p < 0.001). In the multivariate analysis, decompensated cirrhosis was associated with increased mortality (p < 0.001, aOR 2.86 95% CI 1.90-4.32).

CONCLUSION

This study shows the presence of cirrhosis to result in higher hospital mortality and postinfluenza complications in patients with influenza infection.

Effect of temperature on optical and electronic properties of InGaP/InGaAIP multiple quantum wells

The optical and electronic properties in an InGaP/InGaAIP multiple quantum well (MQW) grown by using molecular-beam epitaxy utilizing the digital alloy technique were investigated through temperature-dependent photoluminescence (PL) measurements and numerical calculations. The high-resolution transmission electron microscopy images showed that the sample clearly displayed the InGaP wells and the InGaAIP barriers and separate confinement heterostructure layers. The PL measurements at various temperatures were performed to investigate the interband transitions of the InGaP/InGaAIP MQW. The electronic subband energies and the wavefunctions in the InGaP/InGaAIP MQW at several temperatures were determined by using a finite element method employing the standard 8-band k x p Lagrangian. The numerical results for optical interband transition energies from the ground state electron subband to the ground state heavy-hole subband of the InGaP/InGaAIP MQW at various temperatures were in reasonable agreement with the excitonic transition energies observed in the PL measurements.

Irradiation-induced shrinkage and expansion mechanisms of SiO2 circle membrane nanopores

20 nm diameter SiO(2) nanopore arrays on gradient-thickness membranes were formed by a focused electron beam with in situ transmission electron microscopy (TEM). Nanopore shrinkage was seen in nanopores on thicker membranes, with the rate of diameter change remaining constant during the shrinkage process. In contrast, pore expansion was observed in thinner membranes, with the expansion rate being constant at the initial stage but with a slight increase at the later stage. The geometry model of shrinkage and expansion of the nanopores in relation to the electron irradiation time was investigated by utilizing the TEM tilting method.

Apparatus and method for achieving reproducible measurements of diauxic lag length and anoxic net maximum specific growth rate

An apparatus for continuous growth of pure bacterial cultures under oxic conditions followed by a switch to anoxic batch conditions was designed. The application of this apparatus gave variability of measured parameters (diauxic lag length, anoxic net maximum specific growth rate) which were significantly lower than the variability of previously reported data. The improvement is attributed to more consistent nitrate reductase levels as a result of achieving steady state under oxic condition prior to switching to anoxic batch conditions.

Bioconversion studies in cultured cells of Corydalis species

Structural analysis of the metabolites of dopamine and salsolinol in cultured cells of Corydalis species was carried out using the combination of LC-MS and LC-NMR techniques. Metabolic pathways were clarified without the need to isolate the individual metabolites.

Measurement of glutathione in activated sludges

Thermal, electric, mechanical or oxidative stress seem a promising way to reduce the production of excess activated sludge during biological wastewater treatment. However, the adaptation and the resistance of the sludge microbial ecosystem to stress conditions is a major question as it may definitively limit the effect of some treatments. Defence mechanisms developed by aerobic organisms, in particular, in response to oxidative stress involve various antioxidant activities and compounds such as glutathione. An HPLC method was developed for measuring reduced and total glutathione (GSH and GSHt) in perchloric acid sludge extracts. The method was sensitive, highly specific and validated for linearity, precision and recovery. Considering the extraction yield and the oxidation of GSH during extract storage, the measured GSH concentration was estimated to represent 60% of the GSH content from activated sludges. GSHt ranged from 0.32 to 3.34micromolg(-1) volatile solids and the GSH/GSHt ratio ranged from 32% to 91%. Measurements performed on sludges stressed in precise conditions selected to reach a reduction of sludge production showed a decrease of GSH and GSHt concentrations with thermal, mechanical, electric and ozone stress.

Significance of denitrifying enzyme dynamics in biological nitrogen removal processes: a simulation study

Activated Sludge Model No. 1 (ASM1) was extended to include the enzyme kinetics of denitrifying bacteria switching between oxygen and nitrate as electron acceptors. The extended ASM1 (eASM1) model was applied to two different periodic process configurations, fed-batch and Biodenipho, commonly used for nitrogen removal from wastewater. Predictions of optimal unaerated volume fraction (UVF) by eASM1 were similar to those by ASM1 for both the fed-batch and Biodenipho processes. However, eASM1 predicted substantially longer optimal cycle lengths than ASM1 for both processes. Predictions of optimal UVF and cycle length for the Biodenipho process by eASM1 were closer to current operational values for the University of Florida Biodenipho process than predictions by ASM1.

In vitro effects of hydroxybenzaldehydes from Gastrodia elata and their analogues on GABAergic neurotransmission, and a structure-activity correlation

The present study was designed to characterize the modulatory effects of the constituents of Gastrodia elata and their analogues on the GABAergic neurotransmission. 4-Hydroxybenzaldehyde (1) and 4-hydroxy-3-methoxybenzaldehyde (4) inhibited potently the activity of GABA transaminase (IC(50) = 4.1 and 5.4 microg/ml, respectively), while the activity of another constituent, 4-hydroxybenzyl alcohol (2), was very weak. Further investigation with 10 analogues revealed a structure-activity correlation, suggesting that the aldehyde group and the hydroxy group at C-4 are necessary for the inhibitory effect on the enzyme activity. Some potent enzyme inhibitors were examined for the effect on the radioligands to the GABA(A) receptor complexes of rat cerebral cortices. Among them, the component 4 dose-dependently increased (20 - 30 %) the binding of [(3)H]flunitrazepam in the presence of GABA.

Biphasic inactivation kinetics of Escherichia coli in liquid whole egg by high hydrostatic pressure treatments

Kinetic studies on the isothermal high hydrostatic pressure (HHP) inactivation of Escherichia coli in liquid whole egg (LWE) were performed at 5 and 25 degrees C in the pressure range of 250-400 MPa. The characteristic tailing inactivation curves were described by a first-order biphasic model. As compared to a previous rheological study, it is suggested that the phase change of LWE during pressure treatment affects the inactivation rate of E. coli. Within the processing criteria where the rheological properties of LWE were still comparable to those of fresh LWE, HHP treatments at 5 degrees C induced more E. coli inactivations than those at 25 degrees C. From the results of approximately 3 log reductions of E. coli and over 5 log reductions of Pseudomonas and Paenibacillus, HHP treatment of LWE at 5 degrees C is regarded to be as effective as conventional thermal pasteurization. However, no post-process contamination and the consistency of temperature during preparation, HHP treatment, and storage provide clear processing advantages.

In vitro cytotoxicity of the protoberberine-type alkaloids

In vitro cytotoxic activities of 24 quaternary protoberberine alkaloids related to berberine have been evaluated using a human cancer cell line panel coupled with a drug sensitivity database. Extending the alkyl chain at position 8 or 13 strongly influenced the cytotoxic activity, that is, relative lipophilicity as well as the size of the substituent affects cytotoxicity. The highest level of activity was observed in 8- or 13-hexyl-substituted derivatives of berberine. Structure-activity relationships are described.

NMDA recepter-mediated neuroprotection by essential oils from the rhizomes of Acorus gramineus

Acori graminei Rhizoma (AGR) is shown to exhibit a number of pharmacological actions including sedation and anticonvulsive action. To further characterize its actions in the CNS, the present study evaluated the effects of essential oils (EO) from AGR on the excitotoxic neuronal cell death induced in primary rat cortical cell cultures. EO inhibited the glutamate-induced excitotoxicity in a concentration-dependent manner, with the IC50 of 0.241 mg/ml. EO exerted more potent neuroprotection against the toxicity induced by NMDA (IC50 = 0.139 mg/ml). In contrast, the AMPA-induced toxicity was not inhibited by EO. Receptor-ligand binding studies were performed to investigate the neuroprotective action mechanism. EO dramatically inhibited the specific bindings of a use-dependent NMDA receptorion channel blocker [3H]MK-801, indicating an NMDA receptor antagonist-like action. However, the bindings of [3H]MDL 105,519, a ligand selective for the glycine binding site of NMDA receptor, were not considerably inhibited. These results demonstrated that EO extracted from AGR exhibited neuroprotective effects on cultured cortical neurons through the blockade of NMDA receptor activity, and that the glycine binding site appeared not to be the major site of action.

4-Hydroxybenzaldehyde from Gastrodia elata B1. is active in the antioxidation and GABAergic neuromodulation of the rat brain

Ether fraction of G. elata methanol extract significantly inhibited the recovery time and severity induced by pentylenetetrazole (PTZ) treatment. Pretreatment of ether fraction of G. elata methanol extract successfully prevented diminution of brain GABA level in subconvulsive dose of PTZ-treated rats. 4-Hydroxybenzaldehyde, an analogue of p-hydroxybenzyl alcohol, showed an inhibitory effect on the GABA transaminase, and its inhibitory activity was higher than that of valproic acid, a known anticonvulsant. In the brain of PTZ-treated rats, brain lipid peroxidation was significantly increased, while it recovered to the control level after treatment with 4-hydroxybenzaldehyde. It may be concluded that antioxidation and positive modulation of GABAergic neuromodulation of 4-hydroxybenzaldehyde partially contribute to an antiepileptic and anticonvulsive activity of G. elata B1.

Antimutagenic activity of 5alpha-cholest-7-en-3beta-ol, a new component from the starfish asterina pectinifera

From the butanol fraction of the starfish Asterina pectinifera Müler et Troschel (Asteriidae), we have isolated a new component, 5alpha-cholest-7-en-3beta-ol. Its antigenotoxic and antimutagenic activities were examined by the SOS chromotest with Escherichia coli PQ37 and by Ames test with Salmonella typhimurium TA1538, respectively. 5alpha-Cholest-7-en-3beta-ol showed potent antigenotoxic activity against the mutagens, both MNNG and NQO. For 100% of antigenotoxicity, the concentration of the compound applied against MNNG and NQO were 10 microg and 5 microg per reaction tube, respectively. Its antimutagenic activity with S. typhimurium TA1538 against the mutagen MNNG was very effective. When its concentrations were varied from 1 up to 10 microg dose per plate, the inhibition ratio of revertant CFU of TA1538 per plate was increased accordingly, from 25.2 to 99.2%. These results suggest that 5alpha-cholest-7-en-3beta-ol possesses antigenotoxic and antimutagenic activity and might be useful as a chemopreventive agent.

A new steroidal alkaloid from the roots of Cynanchum caudatum

A new steroidal alkaloid, 12-O-nicotinoylsarcostin, gagamine (1), was isolated from the roots of Cynanchum caudatum Max. (Asclepiadaceae), together with a known alkaloid, gagaminine (2). Their structures were established using spectroscopic methods, some 13C-NMR data of 2 have to be revised.

Inhibitory effects of constituents of Gastrodia elata Bl. on glutamate-induced apoptosis in IMR-32 human neuroblastoma cells

The inhibitory effects of the constituents of Gastrodia elata Bl. (GE) on glutamate-induced apoptosis in human neuronal cells were investigated using IMR32 human neuroblastoma cells. Glutamate (GLU) induced DNA fragmentation, a hallmark of apoptosis, in a dose-dependent manner. GLU also induced a slow and sustained increase in intracellular Ca2+ concentration. Treatment with EGTA, an extracellular Ca2+ chelator, in a nominal Ca2+-free buffer solution abolished the GLU-induced intracellular Ca2+ increase, indicating that GLU stimulated Ca2+ influx pathway in the IMR32 cells. BAPTA, an intracellular Ca2+ chelator, significantly inhibited the GLU-induced apoptosis assessed by the flow cytometry measuring hypodiploid DNA content indicative of apoptosis, implying that intracellular Ca2+ rise may mediate the apoptotic action of GLU. Vanillin (VAN) and p-hydroxybenzaldehyde (p-HB), known constituents of GE, significantly inhibited both intracellular Ca2+ rise and apoptosis induced by GLU. These results suggest that the apoptosis-inhibitory actions of the constituents of GE may account, at least in part, for the basis of their antiepileptic activities. These results further suggest that intracellular Ca2+ signaling pathway may be a molecular target of the constituents of GE.

Structure-activity relationships of protoberberines having antimicrobial activity

13-Alkyl derivatives (2-6 and 8-12) of berberine (1) and palmatine (7) were subjected to in vitro antibacterial activity tests against Bacillus subtilis and Salmonella enteritidis. Antibacterial activity increased as the length of the C-13 aliphatic side chain increased. The effects of the oxygen-substituents on aromatic rings A, C, and D of protoberberinium salts 13-20 on the antimicrobial activity against Staphylococcus aureus, B. subtilis, S. enteritidis, Escherichia coli, and Candida albicans are also discussed. The change in lipophilicity of the protoberberinium salts caused by modification of the substituents appears to influence the antibacterial activity. 13-Hexylberberine (6) and 13-hexylpalmatine (12) exhibited the greatest antibacterial activity.

Antimicrobial activity of 8-alkyl- and 8-phenyl-substituted berberines and their 12-bromo derivatives

The 8-alkyl- (3-6), 8-phenyl- (7), 12-bromo- (8), 8-alkyl-12-bromo- (9-12), and 12-bromo-8-phenyl- (13) berberine derivatives were prepared and tested for their antimicrobial activity in vitro to evaluate structure-activity relationships. Introduction of the alkyl or phenyl group and the bromine atom into the C-8 and C-12 positions of berberine (1), respectively, led to significant increases of the antimicrobial activity. In both the 8-alkyl- and 8-alkyl-12-bromo-berberines (3-6 and 9-12, respectively), the antibacterial activity increased as the length of the aliphatic chain increased. The exception was the activity against Candida albicans and Escherichia coli, which did not always increase as the alkyl side chain lengthened. Among the compounds tested, 12-bromo-8-n-hexylberberine (12) was 64, 256, 128, 16, and 32 times more active against Staphylococcus aureus, Bacillus subtilis, Salmonella enteritidis, E. coli, and C. albicans, respectively, in comparison to the clinically used berberine. Compound 12 was also found to be 8, 16, and 128 times more active against S. aureus, S. enteritidis, and C.albicans, respectively, than kanamycin sulfate, but was of the same order of activity against B. subtilis, and only one-fourth as active against E. coli.

Structure-activity relationships of gagaminine and its derivatives on the inhibition of hepatic aldehyde oxidase activity and lipid peroxidation

In order to determine the structure-activity relationships for antioxidative effects of gagaminine, a steroidal alkaloid isolated from the roots of Cynanchum wilfordi (Asclepiadaceae), two derivatives identified as sarcostin and penupogenin were prepared from gagaminine by hydrolysis and reduction. These compounds were evaluated for the inhibitory effects on the aldehyde oxidase activity and on lipid peroxidation in vitro. Furthermore, their effects were compared with those of gagaminine and the related compounds, cinnamic acid and nicotinic acid. The results of this study prove that the cinnamoyl group in the structure of gagaminine is critical in inhibition of the aldehyde oxidase activity while the nicotinoyl group may be necessary for anti-lipid peroxidation of the compound.

Inhibitory effects of gagaminine, a steroidal alkaloid from Cynanchum wilfordi, on lipid peroxidation and aldehyde oxidase activity

Gagaminine, a steroidal alkaloid, was isolated for the first time from the root of Cynanchum wilfordi Hemsley (Asclepiadaceae), and its effects on lipid peroxidation and the activity of aldehyde oxidase (EC. 1.2.3.1) were investigated in vitro. This alkaloid suppressed significantly the formation of lipid peroxides in rat liver tissues and potently inhibited the hepatic aldehyde oxidase activity in a dose-dependent manner, with IC50 value of 0.8 microM (0.5 microg/ml). These results indicate that gagaminine is a potent natural antioxidant and may be useful for clinical tests.