The association between smoking cessation and lifestyle/genetic variant rs6265 among the adult population in Taiwan

Recent studies showed significant associations between socio-demographic, lifestyle factors, polymorphic variant rs6265, and smoking cessation behaviours. We examined rs6265 TT, TC and CC genotypes and their association with socio-demographic and other variables, including mental health status, drinking, exercise, and smoking behaviour among Taiwanese adults. Data on rs6265 were retrieved from the Taiwan Biobank, which contained genetic data collected between 2008 to 2019 from 20,584 participants (aged 30-70 years). Participants who smoked for more than 6 months prior to enrolment were categorized as smokers. If they had smoked and later quit for more than 6 months, they were classified as former smokers. Information regarding drinking, exercise, depression, and bipolar disorder were obtained through questionnaires and were categorized as either as affirmative (yes) or negative (no) responses. In contrast to previous studies, we found that the association between the polymorphism rs6265 and smoking behaviour was not significant (P-value = 0.8753). Males with lower education levels, young persons, and alcohol drinkers showed significant smoking behaviours (P-value < .0001). This population-based study indicates that rs6265 has no significant correlations with smoking cessation behaviour among adults in Taiwan.

Spine, hip, and femoral neck bone mineral density in relation to vegetarian type and status among Taiwanese adults

We determined the association of vegetarian type and status with bone mineral density (BMD) Z-scores at the spine, hip, and femoral neck. Compared to non-vegetarians, current vegetarians, especially vegans, lacto-vegetarians, and lacto-ovo-vegetarians had lower Z-scores at multiple sites. Sole reliance on a vegetarian diet might be detrimental to the bone.

PURPOSE

The impact of vegetarian diets on BMD is contentious. We determined the association of vegetarian type and status with the spine, hip, and femoral neck BMD Z-scores.

METHODS

We analyzed data from 20,110 Taiwan Biobank volunteers. BMD was measured using dual-energy X-ray absorptiometry (DXA). The vegetarian status (non-, former, and current vegetarians) and type (non-vegetarians, ovo-vegetarians, lacto-vegetarians, lacto-ovo-vegetarians, and vegans) were determined using questionnaires.

RESULTS

The participants consisted of 12,910 women and 7200 men, with a mean age of 55.5 years. Based on vegetarian status (reference: non-vegetarians), current vegetarians had significantly lower BMD Z-scores at the spine (unstandardized regression coefficient, B =  - 0.195, p = 0.006), left hip (B =  - 0.125, p = 0.008), and right hip (B =  - 0.100, p = 0.027), respectively. Based on vegetarian status and type (reference: non-vegetarians), current vegans and non-vegans had notably lower BMD Z-scores at specific skeletal sites. For non-vegans, the BMD Z-scores were significant at the spine (B = -0.184, p = 0.010), left hip (B =  - 0.124, p = 0.010), and left femoral neck (B =  - 0.125, p = 0.012). For current vegans, however, the BMD Z-scores were significant only at the right hip (B =  - 0.232; p = 0.028). Nonetheless, after stratifying vegetarian diet into more subgroups, current vegans exhibited a significant reduction in BMD Z-scores at the spine and right hip, with B-coefficients of - 0.326 and - 0.238, respectively. Current lacto-vegetarians also had significantly lower Z-scores (p < 0.05) at the spine (B =  - 0.459), left hip (B =  - 0.313), and right hip (B =  - 0.214). Moreover, current lacto-ovo-vegetarians had significantly lower Z-scores at the spine (B =  - 0.175) and left hip (B =  - 0.115).

CONCLUSION

Current vegetarians, particularly vegans, lacto-vegetarians, and lacto-ovo-vegetarians, demonstrated significantly lower BMD Z-scores at various skeletal sites compared to non-vegetarians. Sole reliance on a vegetarian diet might be detrimental to the bone.

The association between vegetarian diet and varicose veins might be more prominent in men than in women

Background

Varicose veins (VVs), a common vascular disease is associated with a huge medical burden. The prevalence in women surpasses that in men. The role of vegetarian diets in the pathogenesis of the disease remains inconclusive. In this study, we examined the risk of VVs in vegetarian and non-vegetarian men and women.

Methods

The study involved 9905 adults whose data were obtained from Taiwan Biobank between 2008 and 2020. Information on VVs, sex, and vegetarian diets was obtained from participants' self-responses to the Taiwan Biobank questionnaires.

Results

The study subjects consisted of 4,142 men and 5,763 women. About 12% of men and 35% of women had VVs. Study participants were predominantly non-vegetarians (91.84% were men and 88.24% were women). Women had a higher risk of VVs than men. The odds ratio (OR); 95% confidence interval (CI) was 3.414; 2.995-3.891. There was a significant interaction between sex and vegetarian diets (p = 0.0034). Women were at higher risk of VVs than men both in the vegetarian (OR = 1.877, 95% CI = 1.270-2.774) and non-vegetarian (OR = 3.674, 95% CI = 3.197-4.223) groups. Based on vegetarian diets, only vegetarian men had a higher risk of VVs (OR = 1.453, 95% CI = 1.069 to 1.976). Based on the sex-stratified model, the risk of VVs was significantly higher in vegetarian men (OR = 1.457, 95% CI = 1.072-1.979), and in vegetarian and non-vegetarian women with corresponding ORs (95% CI) of 3.101 (2.528-3.803) and 3.599 (3.140-4.124), respectively.

Conclusion

Women were more susceptible to varicose veins compared to men, regardless of diet. However, in terms of diet, only men who followed a vegetarian diet were at greater risk for developing VVs.

[Prediction of protection probability against Omicron BA.1, BA.4 and BA.5 variants in symptomatic infections with prototype strain based on neutralization antibody levels]

Objective: To predict the protection probability of different clinical outcomes after reinfection with Omicron variant in symptomatic and unvaccinated COVID-19 patients who infected with prototype strain. Methods: The data used in this study were derived from a systematic review and meta-analysis which systematically searched PubMed, Embase, Web of Science, and Europe PMC databases, included published and uploaded studies of dynamic changes of neutralizing antibodies in symptomatic COVID-19 patients from 1 January 2020 to 2 October 2022 and extracted the literature information, study design, serological experiment information and antibody results. According to the scatter distribution characteristics of antibody titer data, a generalized additive model based on Gaussian distribution was used to fit the titer value of neutralizing antibody based on logarithmic conversion and the dynamic change pattern of neutralizing antibody in symptomatic and unvaccinated COVID-19 patients infected with prototype strain over time was obtained. In this study, the fitted antibody titers of patients on the 28th, 51st, and 261st day after symptom onset was selected to predict the protection probability. Results: Neutralizing antibodies produced in symptomatic and unvaccinated patients infected with prototype strain could provide protection against Omicron reinfection, and the probability of protection gradually decreased with time. Neutralizing antibody level on day 28 after symptom onset provided protection probability of 30.3% (95%CI: 20.0%-45.5%) against reinfection, 51.5% (95%CI: 33.4%-75.9%) against symptomatic reinfection, and 91.2% (95%CI: 77.1%-97.7%) against severe reinfection caused by Omicron BA.5. The protection probability against Omicron BA.1, BA.4 and BA.5 reinfections decreased significantly 261 days after symptom onset, showing 9.6%-12.9%, 18.4%-23.9% and 63.1%-70.3% against three clinical outcomes, respectively. At the same time point and against the same clinical outcome, the protection probability of BA.1 was the highest, followed by BA.4 and BA.5. Conclusions: Neutralizing antibodies induced in symptomatic and unvaccinated COVID-19 patients previously infected with the prototype strain have limited protection probability against Omicron BA.5 reinfections and symptomatic reinfections. The protection probability against Omicron BA.5 reinfections is 30.3% 28 days after symptom onset and decreases to about 10% after 261 days. However, the protection probability against severe reinfections is considerable, with over 90% 28 days after symptom onset and still exceeding 60% after 261 days.

Associations Between Body Mass Index, WNT16 rs2908004 and Osteoporosis: Findings from Taiwan Biobank

Purpose

Osteoporosis is a degenerative disease that affects women and men of all races. We studied the association between body mass index (BMI), rs2908004 polymorphism of the WNT16 gene, and osteoporosis using data from Taiwan Biobank (TWB).

Patients and Methods

We analyzed data from 10,942 subjects aged 30 to 70. We defined osteoporosis based on a mean T-score of -2.5 and below in the hip. Body mass index was classified following the guidelines of the Health Promotion Administration. Imputation was carried out using the IMPUTE2 (v2.3.1) program. Multiple logistic regression was used for analysis. The odds ratios (ORs) and 95% confidence interval (CI) for osteoporosis were determined.

Results

In the multivariate regression model, variant rs2908004 had a significant association with osteoporosis. That is, the rs2908004-GA+AA genotype was associated with lower osteoporosis risk than the GG genotype (OR, 0.651; 95% CI = 0.544 to 0.780). Compared to normal-weight, underweight was significantly associated with a higher risk of osteoporosis (OR, 6.517; 95% CI = 4.624 to 9.186) while overweight and obesity were protective (OR, 0.176; 95% CI = 0.140 to 0.221 and 0.057; 95% CI = 0.039 to 0.083, respectively). There was an interaction between rs2908004 and BMI (p = 0.0148). Subgroup analyses (using rs2908004-GG/normal-weight as the reference group) indicated ORs of 7.66 (95% CI = 5.153 to 11.394) in the rs2908004-GG/underweight group and 3.002 (95% CI = 1.509 to 5.974) in the rs2908004-GA+AA/underweight group (95% CI = 1.509 to 5.974). Odds ratios were substantially lower in rs2908004-GG/obese, rs2908004-GG/overweight, GA+AA/normal-weight, rs2908004-GA+AA/overweight, and rs2908004-GA+AA/obese groups, respectively.

Conclusion

According to our study, underweight was associated with an increased risk of osteoporosis irrespective of WNT16 rs2908004 genotypes, while overweight and obesity were associated with a lower risk.

Risk of gallstones based on ABCG8 rs11887534 single nucleotide polymorphism among Taiwanese men and women

BACKGROUND

Gallstones are abnormal masses caused by impaired metabolism of cholesterol, bilirubin, or bile salts in the gallbladder or biliary tract. ATP-binding cassette subfamily G member 8 (ABCG8) is a protein that regulates cholesterol efflux from the liver. Genome-wide association studies (GWAS) and meta-analyses of GWAS revealed the ABCG8 rs11887534 variant as the most common genetic determinant of gallstones in humans. These findings have not been extensively replicated in Taiwanese. Therefore, we appraised the relationship between gallstones and rs11887534 in a relatively large Taiwanese sample.

METHODS

We retrieved data collected through questionnaires, physical and biochemical tests from the Taiwan Biobank Bank (TWB). The study participants comprised 7388 men and 13,880 women who voluntarily enrolled in the Taiwan Biobank project between 2008 and 2019. Gallstones were self-reported.

RESULTS

The overall sample size was 21,268 comprising 938 gallstone patients and 20,330 non-gallstone individuals. Among the participants, 20,640 had the GG and 628 had the GC + CC genotype. At p-value < 0.05, the baseline genotypes and gallstone status between men and women were not significantly different. The risk of gallstones was higher in participants having the GC + CC compared to the GG genotype: odds ratio (OR); 95% confidence interval (CI) = 1.698; 1.240-2.325), but was lower in men compared to women (OR = 0.763; 95% CI = 0.638-0.913). Compared to men with the rs11887534 GG genotype, women with the GG and GC + CC genotypes had a higher risk of gallstone (OR; 95% CI = 1.304; 1.087-1.565 for GG and 2.291; 1.514-3.467 for GC + CC). The positive association between GC + CC and gallstones was retained after we restricted the analysis to the female participants (OR; 95% CI = 1.789 = 1.208-2.648). Hormone use was associated with an elevated risk of gallstones (OR; 95% CI = 1.359; 1.107-1.668). Relative to GG and no hormone use, we found a significantly high risk among hormone users with the GC + CC genotype (OR; 95% CI = 3.596; 1.495-8.650).

CONCLUSIONS

The rs11887534 GC + CC genotype was independently associated with a higher risk of gallstones. This risk was much higher among women, especially those who used hormones for various gynecological purposes.

Research progress in bioremediation of petroleum pollution

With the enhancement of environmental protection awareness, research on the bioremediation of petroleum hydrocarbon environmental pollution has intensified. Bioremediation has received more attention due to its high efficiency, environmentally friendly by-products, and low cost compared with the commonly used physical and chemical restoration methods. In recent years, bacterium engineered by systems biology strategies have achieved biodegrading of many types of petroleum pollutants. Those successful cases show that systems biology has great potential in strengthening petroleum pollutant degradation bacterium and accelerating bioremediation. Systems biology represented by metabolic engineering, enzyme engineering, omics technology, etc., developed rapidly in the twentieth century. Optimizing the metabolic network of petroleum hydrocarbon degrading bacterium could achieve more concise and precise bioremediation by metabolic engineering strategies; biocatalysts with more stable and excellent catalytic activity could accelerate the process of biodegradation by enzyme engineering; omics technology not only could provide more optional components for constructions of engineered bacterium, but also could obtain the structure and composition of the microbial community in polluted environments. Comprehensive microbial community information lays a certain theoretical foundation for the construction of artificial mixed microbial communities for bioremediation of petroleum pollution. This article reviews the application of systems biology in the enforce of petroleum hydrocarbon degradation bacteria and the construction of a hybrid-microbial degradation system. Then the challenges encountered in the process and the application prospects of bioremediation are discussed. Finally, we provide certain guidance for the bioremediation of petroleum hydrocarbon-polluted environment.

[Effect of electroacupuncture combined with caudal epidural injection on functional rehabilitation of patients with lumbar hernia]

OBJECTIVE

To observe the effect of electroacupuncture (EA) combined with caudal epidural injection on subjective pain, walking capability, lumbar flexibility and muscle strength in patients with lumbar disc hernia (LDH).

METHODS

Sixty LDH patients were randomly allocated to the control group and the research group. The patients of the control group received ultrasound guided caudal epidural injection, and those of the research group received EA combined with ultrasound guided caudal epidural injection. Bilateral Jiaji (EX-B2) and adjunct points Guanyuanshu (BL26), Shenshu (BL23), Chengfu (BL36), Huantiao (GB30), Zhibian (BL54), etc. on the affected side were stimulated with EA (2 Hz/16 Hz, 5-8 mA) for 30 min each time, once every other day for 4 weeks, with 2 days' rest between every two weeks. The patients' pain was evaluated by using visual analogue scale (VAS), walking capability assessed by timed-up and go (TUG) test (time of walking back and forth in 3 m distance), lumbar flexibility (range of motion, ROM) detected by using an inclinometer and the strength of the lumbar flexor and extensor determined by using a push-pull dynamometer.

RESULTS

After the treatment, self-comparison showed that the VAS score and TUG-measured time in both groups were significantly decreased (P<0.01, P<0.05), and the post-bucking ROM and extension ROM in the research group, and the lumbar flexor and extensor muscle strength in both groups were obviously increased compared with their own pre-treatment (P<0.05). Comparison between two groups showed that the VAS score and TUG-measured time of the research group were significantly lower than those of the control group (P<0.01), while the lumbar flexor's ROM as well as the extensor's strength were significantly higher in the research group than in the control group (P<0.05).

CONCLUSION

For patients with LDH, EA combined with caudal epidural injection can alleviate pain, improve the walking capability, lumbar flexibility and strength of the lumbar extensor, and the therapeutic effect of the combined treatment is significantly better than that of simple caudal epidural injection.

Association of Age and Sex with Metabolic Syndrome in Taiwanese Adults

Objective

This study aimed to investigate the association of age and sex with metabolic syndrome (MS) in Taiwanese adults.

Methods

We extracted information of 4307 men and 4783 women aged 30–70 from the Taiwan Biobank.

Results

The interaction between age and sex on MS was significant (p-value = 0.0001). After stratification by sex, men and women aged 50–70 years (reference: 30≤age<50 years) had a higher risk of MS. The odds ratio (OR), 95% confidence interval (CI) was 2.316, 1.936–2.772 in men and 3.101, 2.561–3.754 in women. After stratification by age, men aged 50–70 years had a lower risk of MS compared to women (OR, 95% CI = 0.713, 0.598–0.851).

Conclusion

The interaction between age and sex on MS was significant. Sex-wise, both men and women aged 50–70 years had a higher likelihood of MS. Age-wise, men aged 50–70 years had a lower risk of MS compared to women.

Structural elucidation and antidiabetic activity of fucosylated chondroitin sulfate from sea cucumber Stichopus japonicas

A fucosylated chondroitin sulfate was isolated from the body wall of sea cucumber Stichopus japonicus (FCSsj), whose structure was characterized by NMR spectroscopy and HILIC-FTMS. At the ratio of 1.00:0.26:0.65, three fucosyl residues were found: 2,4-disulfated-fucose (Fuc2,4S), 4-sulfated-fucose (Fuc4S) and 3,4-disulfated-fucose (Fuc3,4S), which were only linked to the O-3 of glucuronic acid residues (GlcA). Besides mono-fucosyl moieties, di-fucosyl branches, namely Fuc2,4Sα(1→3)Fuc4S, were also found to be attached to the O-3 of GlcA. The antidiabetic activity of FCSsj was evaluated using glucosamine induced insulin resistant (IR) Hep G2 cells in vitro. It was found that FCSsj significantly promoted the glucose uptake and glucose consumption of IR-Hep G2 cells in a dose-dependent manner, and could alleviate the cell damage. Furthermore, FCSsj could promote the glycogen synthesis in the glucosamine-induced IR-Hep G2 cells. These results provided a supplement for studying the antidiabetic activity of FCSsj.

Interactive association between dietary fat and sex on CDH13 cg02263260 methylation

BACKGROUND

DNA methylation of Cadherin 13 (CDH13), a tumor suppressor gene is associated with gene repression and carcinogenesis. We determined the relation of dietary fat and sex with CDH13 cg02263260 methylation in Taiwanese adults.

METHODS

Data of 870 eligible participants (430 men and 440 women) between 30 and 70 years were obtained from the Taiwan Biobank (TWB) database. The association of dietary fat and sex with CDH13 cg02263260 methylation was determined using multiple linear regression.

RESULTS

The association between sex and cg02263260 methylation was significant: beta-coefficient (β) = 0.00532; 95% confidence interval (CI) = 0.00195-0.00868. Moreover, the interaction between sex and dietary fat on cg02263260 methylation was significant (P-value = 0.0145). After stratification by sex, the association of dietary fat with cg02263260 methylation was significant only in women. Specifically, high dietary fat was positively associated with cg02263260 methylation in women (β = 0.00597; 95% CI = 0.00061-0.01133) and the test for trend was significant (P-value = 0.0283).

CONCLUSION

High fat intake was significantly associated with higher cg02263260 methylation in women and the test for trend was significant. These findings suggest that the association of fat intake and CDH13 cg02263260 might vary by sex and CDH13 cg02263260 methylation levels in women might increase as fat intake increases.

AHRR cg05575921 methylation in relation to smoking and PM2.5 exposure among Taiwanese men and women

Background

Polycyclic aromatic hydrocarbon (PAH)-rich substances like cigarette smoke and PM_2.5 induce aryl hydrocarbon receptor (AHR)-mediated aryl hydrocarbon receptor repressor (AHRR) methylation. AHRR cg05575921 and coagulation factor II (thrombin) receptor-like 3 (F2RL3) cg03636183 methylation patterns are well-established biomarkers for smoking. Even though AHRR cg05575921 methylation has recently been associated with PM_2.5, the interaction between smoking and PM_2.5 on AHRR methylation is yet to be fully explored. We evaluated AHRR and F2RL3 CpG sites to identify potential significant markers in relation to PM_2.5 and smoking in Taiwanese adults.

Methods

DNA methylation and smoking data of 948 participants aged 30–70 years were obtained from the Taiwan Biobank Database (2008–2015), while PM_2.5 data were obtained from the Air Quality Monitoring Database (2006–2011).

Results

Smoking and PM_2.5 were independently associated with hypomethylation (lower levels) of AHRR cg05575921, AHRR cg23576855, F2RL3 cg03636183, and F2LR3 cg21911711 after multiple-comparison correction (Bonferroni P < 0.00028409). Cg05575921 was the most hypomethylated AHRR CpG site, while cg03636183 was the most hypomethylated F2RL3 CpG site. Overall, cg05575921 was the most hypomethylated CpG site: β = − 0.03909, P < 0.0001; − 0.17536, P < 0.0001 for former and current smoking, respectively (P-trend_smoking < 0.0001) and − 0.00141, P < 0.0001 for PM_2.5. After adjusting for F2RL3 cg03636183, smoking and PM_2.5 remained significantly associated with cg05575921 hypomethylation: β − 0.02221, P < 0.0001; − 0.11578, P < 0.0001 for former and current smoking, respectively (P-trend_smoking < 0.0001) and − 0.0070, P = 0.0120 for PM_2.5. After stratification by sex, smoking and PM_2.5 remained associated (P < 0.05) with cg05575921 hypomethylation in both men (β = − 0.04274, − 0.17700, and − 0.00163 for former smoking, current smoking, and PM_2.5, respectively) and women (β = − 0.01937, − 0.17255, and − 0.00105 for former smoking, current smoking, and PM_2.5, respectively). After stratification by residential area, former and current smoking remained associated (P < 0.05) with cg05575921 hypomethylation: β = − 0.03918 and − 0.17536, respectively (P-trend_smoking < 0.0001). Living in the central and southern areas was also associated (P < 0.05) with cg05575921 hypomethylation: β = − 0.01356 and − 0.01970, respectively (P-trend_area < 0.0001).

Conclusion

Smoking and PM_2.5 were independently associated with hypomethylation of cg05575921, cg23576855, cg03636183, and cg21911711. The most hypomethylated CpG site was cg05575921 and its association with smoking and PM_2.5 was dose-dependent.

Vegetarian Diets along with Regular Exercise: Impact on High-Density Lipoprotein Cholesterol Levels among Taiwanese Adults

Background and objectives: High-density lipoprotein cholesterol (HDL-C) is important for improving risk estimates of atherosclerotic cardiovascular disease. We investigated the effect of omnivore and diverse vegetarian diets in connection with exercise on HDL-C. Materials and Methods: Historical data of 9588 biobank participants (4025 exercisers and 5563 non-exercisers) aged 30-70 years were categorized as omnivores (n = 8589), former vegetarians (n = 544), lacto-ovo vegetarians (n = 417), and strict vegetarians (n = 38). We used multiple linear regression for analyses. Results: HDL-C levels were higher in exercisers compared to non-exercisers. Compared with omnivores, strict vegetarians had decreased levels of HDL-C (β = -5.705; p = 0.001) followed by lacto-ovo vegetarians (β = -3.900; p < 0.001) and former vegetarians (β = -0.329; p = 0.475). The test for trend was significant (p < 0.001). After categorization by exercise modalities, the β-value was -13.984 for strict vegetarians, -4.419 for lacto-ovo vegetarians, and -1.864 for former vegetarians, respectively (p < 0.05). There was an interaction between diet and exercise (p = 0.009). Omnivores who exercised regularly had significantly higher HDL-C, whereas strict vegetarians who exercised regularly had significantly lower HDL-C. Conclusions: In summary, strict vegetarian diets in conjunction with regular exercise might not serve as healthful behaviors to be implemented in everyday life considering the negative impact on HDL-C.

Predicative values of serum microRNA-22 and microRNA-126 levels for non-small cell lung cancer development and metastasis: a case-control study

Presented study aims to explore the predictive values of serum microRNA-22 (miR-22) and miR-126 levels for non-small cell lung cancer (NSCLC) development and metastasis.A total of 127 NSCLC patients who were admitted in the First People's Hospital of Yancheng City from May, 2013 to May, 2015 were selected as the case group, including 71 cases of adenocarcinoma and 56 cases of squamous cell carcinoma. There were 112 healthy individuals selected as the control group. The qRT-PCR was performed to testify the serum miR-22 and miR-126 levels. Logistic regression analysis was conducted to analyze independent factors influencing NSCLC metastasis and receiver operating characteristic (ROC) curve was drawn to analyze the sensitivity and specificity of serum miR-22 and miR-126 levels in predicting NSCLC developments and metastasis.The serum miR-22 level was significantly higher in the case group than that in the control group, while the serum miR-126 level was lower in the case group as compared with that in the control group. Compared with squamous cell carcinoma patients, serum miR-22 level significantly increased, while serum miR-126 level decreased in patients with adenocarcinoma. Patients at III + IV stage showed increased serum miR-22 level and relatively decreased serum miR-126 level as compared to patients at I + II stage. Serum miR-22 level elevated in patients with metastasis; in contrast serum miR-126 level reduced in comparison to those without metastasis. In patients with familial inheritance, serum miR-22 level increased but serum miR-126 level decreased as compared to those without familial inheritance. The specificity and sensitivity of serum miR-22 and miR-126 levels in predicting NSCLC development were 99.11%, 84.30%, 82.68% and 96.40%, respectively. The specificity and sensitivity of serum miR-22 and miR-126 levels in predicting NSCLC metastasis were 59.74%, 96.00%, 84.00% and 62.30%, respectively.Results indicated that serum miR-22 and miR-126 levels may be used as the predicative biomarkers for NSCLC development and metastasis.

The etiology and prognosis of super-refractory convulsive status epilepticus in children

BACKGROUND

Both refractory convulsive status epilepticus (SE) and super-refractory SE are medical emergencies. However, there are limited data on super-refractory SE in children. Thus, this study focuses on characterizing the demographics, outcomes, and prognostic factors for super-refractory SE in children.

METHODS

This study was a retrospective analysis of super-refractory SE treated in a tertiary referral center in Taiwan. The functional outcome was evaluated by modified Rankin scale (mRS). Significant functional decline was defined as an mRS difference (before hospital admission and at discharge) of more than 2. The variates and the follow-up mRS values were then analyzed statistically.

RESULTS

We enrolled 134 patients with 191 episodes of convulsive SE and identified 30 patients with 38 episodes of convulsive super-refractory SE. The incidence of convulsive super-refractory SE in the group with SE was 19.9%, and the age ranged from 2.5 months to 17 years. In-hospital mortality was 13.3%, which was much lower than that of adult cohorts. Newly acquired epilepsy and cognitive deficit occurred in 100% and 88.5%, respectively. Newly acquired epilepsy, as a sequel of super-refractory SE, was observed in all 18 patients (100%) who survived and had no history of epilepsy. Significant functional decline (mRS difference of more than 2) at discharge occurred in 76.7%. Poor functional outcome was associated with acute symptomatic etiology (P < 0.001) and the number of anesthetic agents (P = 0.002). The functional outcome improved after 1 year of follow-up in our population.

CONCLUSIONS

Super-refractory SE is associated with significant morbidity and mortality in children. However, the in-hospital mortality rate is much lower compared with adults. The functional outcome in children is associated with acute symptomatic etiology and the number of anesthetic agents and may improve after long-term follow-up.

Melt fluxing to elevate the forming ability of Al-based bulk metallic glasses

Salt-fluxing treatment is an effective technique to improve the glass-forming ability (GFA) of bulk metallic glass (BMG)-forming melts, as demonstrated before in Pd- and Fe-based systems. However, it has been challenging to develop similar fluxing protocol for more reactive melts, such as Al-rich BMG-forming systems. Here we design new fluxing agents, from a thermodynamics perspective that takes into account combined effects of physical absorption and chemical absorption (reaction) between the fluxing agents and oxide inclusions. MgCl₂-CaCl₂ composite salts were selected, and their fluxing effects were systematically studied on an Al₈₆Ni_6.75Co_2.25Y_3.25La_1.75 alloy, the best BMG-forming composition reported thus far for Al-rich alloy systems. The oxygen content was found to continuously decrease in the master alloy with increasing cycles of salt-fluxing treatment, with chlorate products on the surface suggesting concurrent physical absorption and chemical reaction. The fluxing treatment developed has enabled a record critical size (diameter) of 2.5 mm for Al-based BMGs. Our finding is thus an advance in developing highly desirable Al-based BMGs, and also provides guidance for designing processing protocol to produce larger-sized BMGs in other reactive systems.

[Association between ultrasound screening frequency and mortality in patients with hepatocellular carcinoma]

Objective: To discuss the association between ultrasound screening frequency and total mortality in patients with HCC before diagnosing HCC, and explore the optimal ultrasound screening frequency for HCC high-risk groups. Methods: Retrospectively collected clinical data of 615 cases of liver cirrhosis who developed to HCC from January 1, 2010 to December 31, 2015. Before diagnosing HCC, all patients were divided into five groups according to ultrasound screening frequency: 0-6, 7-12, 13-24, 25-36 months and not screened within 3 years (never screened). The chance to receive curative therapy, 5-year cumulative mortalities and independent factors of mortality in patients with HCC were analyzed. Results: Chances to receive curative therapy among the 0-6, 7-12, 13-24, 25-36 months and never screened groups were 38.2%, 27.2%, 25.4%, 23.8% and 19.7%, respectively (P<0.05). The 5-year overall mortality rates were 76.4%, 77.7%, 79.3%, 82.5% and 84.6%, respectively. Compared with 0-6 months, the adjusted OR of mortality for the other groups were 1.112, 1.235, 1.305 and 1.451, respectively (all P<0.05). Multivariate analysis showed that ultrasound screening frequency, curative treatment and Child-Pugh (class A/B) were the factors to affect long-term survival in patients with HCC (all P<0.05). Conclusion: For HCC high-risk groups, optimal ultrasound screening frequency is within 6 months, and high-frequency ultrasound screening can increase the chance of receiving curative treatment, reduce total mortality, and improve overall survival.

Complexity of Multi-Channel Electroencephalogram Signal Analysis in Childhood Absence Epilepsy

Absence epilepsy is an important epileptic syndrome in children. Multiscale entropy (MSE), an entropy-based method to measure dynamic complexity at multiple temporal scales, is helpful to disclose the information of brain connectivity. This study investigated the complexity of electroencephalogram (EEG) signals using MSE in children with absence epilepsy. In this research, EEG signals from 19 channels of the entire brain in 21 children aged 5-12 years with absence epilepsy were analyzed. The EEG signals of pre-ictal (before seizure) and ictal states (during seizure) were analyzed by sample entropy (SamEn) and MSE methods. Variations of complexity index (CI), which was calculated from MSE, from the pre-ictal to the ictal states were also analyzed. The entropy values in the pre-ictal state were significantly higher than those in the ictal state. The MSE revealed more differences in analysis compared to the SamEn. The occurrence of absence seizures decreased the CI in all channels. Changes in CI were also significantly greater in the frontal and central parts of the brain, indicating fronto-central cortical involvement of “cortico-thalamo-cortical network” in the occurrence of generalized spike and wave discharges during absence seizures. Moreover, higher sampling frequency was more sensitive in detecting functional changes in the ictal state. There was significantly higher correlation in ictal states in the same patient in different seizures but there were great differences in CI among different patients, indicating that CI changes were consistent in different absence seizures in the same patient but not from patient to patient. This implies that the brain stays in a homogeneous activation state during the absence seizures. In conclusion, MSE analysis is better than SamEn analysis to analyze complexity of EEG, and CI can be used to investigate the functional brain changes during absence seizures.

Convergence of PKC-dependent kinase signal cascades on NMDA receptors

Synaptic plasticity, or long-term potentiation (LTP), of excitatory synapses in the hippocampus contributes to learning and the establishment of spatial memories. In the CA1 region, induction of LTP enhances the function of postsynaptic alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptors (AMPARs) because of the Ca2+-calmodulin kinase II (CaMKII)-dependent phosphorylation of this subtype of glutamate receptor. Entry of Ca2+, via N-methyl-D-aspartate receptors (NMDARs), during strong synaptic stimulation provides the stimulus to trigger phosphorylation of AMPARs. However, this induction also requires activation of a protein kinase C (PKC)-dependent tyrosine kinase signal cascade and a concomitant upregulation of NMDARs. This review focuses upon NMDARs as potential targets of PKC and/or of the PKC-dependent tyrosine kinase cascade. PKC, acting via the CAKbeta/Src tyrosine kinase cascade, enhances NMDAR activation and may increase the number of receptors expressed in synapses. In contrast, direct phosphorylation of NMDARs by PKC increases the sensitivity of NMDA channel inactivation to intracellular Ca2+. In CAI neurons, PKC provides a point of convergence of control of NMDARs and synaptic plasticity for a wide variety of G-protein coupled and growth factor receptors.

Role of barium nitrate on the sulfur fixation of calcium oxide

In this paper, the effect of Ba(NO3)2 on the efficiency of sulfur fixation of calcium oxide during coal combustion was studied. The results showed that addition of barium nitrate to the CaO can enhance the sulfur removal rate of CaO significantly. The X-ray diffraction spectrum of residual ash of coal added some sulfur fixative expressed that Ba2+ can form a compound of Ba-Al-Si-O which encloses the CaSO4 to prevent it's decomposition, so Ba2+ can improve the action of sulfur fixation of CaO. The combustion character of the original coal and original coal added sulfur fixative was researched with thermal-gravity analyzer and the results expressed that adding some sulfur fixative to the coal will make the combustion character of coal change little.

In CA1 pyramidal neurons of the hippocampus protein kinase C regulates calcium-dependent inactivation of NMDA receptors

The NMDA subtype of the glutamate-gated channel exhibits a high permeability to Ca(2+). The influx of Ca(2+) through NMDA channels is limited by a rapid and Ca(2+)/calmodulin (CaM)-dependent inactivation that results from a competitive displacement of cytoskeleton-binding proteins from the NR1 subunit of the receptor by Ca(2+)/CaM (Zhang et al., 1998; Krupp et al., 1999). The C terminal of this subunit can be phosphorylated by protein kinase C (PKC) (Tingley et al., 1993). The present study sought to investigate whether PKC regulates Ca(2+)-dependent inactivation of the NMDA channel in hippocampal neurons. Activation of endogenous PKC by 4beta-phorbol 12-myristate 13-acetate enhanced peak (I(p)) and depressed steady-state (I(ss)) NMDA-evoked currents, resulting in a reduction in the ratio of these currents (I(ss)/I(p)). We demonstrated previously that PKC activity enhances I(P) via a sequential activation of the focal adhesion kinase cell adhesion kinase beta/proline-rich tyrosine kinase 2 (CAKbeta/Pyk2) and the nonreceptor tyrosine kinase Src (Huang et al., 1999; Lu et al., 1999). Here, we report that the PKC-induced depression of I(ss) is unrelated to the PKC/CAKbeta/Src-signaling pathway but depends on the concentration of extracellular Ca(2+). Intracellular applications of CaM reduced I(ss)/I(p) and occluded the Ca(2+)-dependent effect of phorbol esters on I(ss.) Moreover, increasing the concentration of intracellular Ca(2+) buffer or intracellular application of the inhibitory CaM-binding peptide (KY9) greatly reduced the phorbol ester-induced depression of I(ss). Taken together, these results suggest that PKC enhances Ca(2+)/CaM-dependent inactivation of the NMDA channel, most likely because of a phosphorylation-dependent regulation of interactions between receptor subunits, CaM, and other postsynaptic density proteins.

Deciphering the role of the electrostatic interactions involving Gly70 in eglin C by total chemical protein synthesis

Eglin c from the leech Hirudo medicinalis is a potent protein inhibitor of many serine proteinases including chymotrypsin and subtilisins. Unlike most small protein inhibitors whose solvent-exposed enzyme-binding loop is stabilized primarily by disulfide bridges flanking the reactive-site peptide bond, eglin c possesses an enzyme-binding loop supported predominantly by extensive electrostatic/H-bonding interactions involving three Arg residues (Arg48, Arg51, and Arg53) projecting from the scaffold of the inhibitor. As an adjacent residue, the C-terminal Gly70 participates in these interactions via its alpha-carboxyl group interacting with the side chain of Arg51 and the main chain of Arg48. In addition, the amide NH group of Gly70 donates an H-bond to the carbonyl C=O groups of Arg48 and Arg51. To understand the structural and functional relevance of the electrostatic/H-bonding network, we chemically synthesized wild-type eglin c and three analogues in which Gly70 was either deleted or replaced by glycine amide (NH(2)CH(2)CONH(2)) or by alpha-hydroxylacetamide (HOCH(2)CONH(2)). NMR analysis indicated that the core structure of eglin c was maintained in the analogues, but that the binding loop was significantly perturbed. It was found that deletion or replacement of Gly70 destabilized eglin c by an average of 2.7 kcal/mol or 20 degrees C in melting temperature. As a result, these inhibitors become substrates for their target enzymes. Binding assays on these analogues with a catalytically incompetent subtilisin BPN' mutant indicated that loss or weakening of the interactions involving the carboxylate of Gly70 caused a decrease in binding by approximately 2 orders of magnitude. Notably, for all four synthetic inhibitors, the relative free energy changes (DeltaDeltaG) associated with protein destabilization are strongly correlated (slope = 0.94, r(2) = 0. 9996) with the DeltaDeltaG values derived from a decreased binding to the enzyme.

Distinct roles of synaptic and extrasynaptic NMDA receptors in excitotoxicity

Excitatory synaptic activity governs excitotoxicity and modulates the distribution of NMDA receptors (NMDARs) among synaptic and extrasynaptic sites of central neurons. We investigated whether NMDAR localization was functionally linked to excitotoxicity by perturbing F-actin, a cytoskeletal protein that participates in targeting synaptic NMDARs in dendritic spines. Depolymerizing F-actin did not affect NMDA-evoked whole-cell currents. However, the number of dendritic NMDAR clusters and the NMDAR-mediated component of miniature spontaneous EPSCs were reduced, whereas the number of AMPA receptor clusters and AMPA receptor-mediated component of EPSCs was unchanged. This selective perturbation of synaptically activated NMDARs had no effect on neuronal death or the accumulation of (45)Ca(2+) evoked by applying exogenous NMDA or L-glutamate, which reach both synaptic and extrasynaptic receptors. However, it increased survival and decreased (45)Ca(2+) accumulation in neurons exposed to oxygen glucose deprivation, which causes excitotoxicity by glutamate release at synapses. Thus, synaptically and extrasynaptically activated NMDARs are equally capable of excitotoxicity. However, their relative contributions vary with the location of extracellular excitotoxin accumulation, a factor governed by the mechanism of extracellular neurotransmitter accumulation, not the synaptic activation of NMDARs.

Src potentiation of NMDA receptors in hippocampal and spinal neurons is not mediated by reducing zinc inhibition

The protein-tyrosine kinase Src is known to potentiate the function of NMDA receptors, which is necessary for the induction of long-term potentiation in the hippocampus. With recombinant receptors composed of NR1-1a/NR2A or NR1-1a/2B subunits, Src reduces voltage-independent inhibition by the divalent cation Zn2+. Thereby the function of recombinant NMDA receptors is potentiated by Src only when the Zn2+ level is sufficient to cause tonic inhibition. Here we investigated whether the Src-induced potentiation of NMDA receptor function in neurons is caused by reducing voltage-independent Zn2+ inhibition. Whereas chelating extracellular Zn2+ blocked the Src-induced potentiation of NR1-1a/2A receptors, we found that Zn2+ chelation did not affect the potentiation of NMDA receptor (NMDAR) currents by Src applied into hippocampal CA1 or CA3 neurons. Moreover, Src did not alter the Zn2+ concentration-inhibition relationship for NMDAR currents in CA1 or CA3 neurons. Also, chelating extracellular Zn2+ did not prevent the upregulation of NMDA single-channel activity by endogenous Src in membrane patches from spinal dorsal horn neurons. Taking these results together we conclude that Src-induced potentiation of NMDAR currents is not mediated by reducing Zn2+ inhibition in hippocampal and dorsal horn neurons.

Platelet-derived growth factor receptor-induced feed-forward inhibition of excitatory transmission between hippocampal pyramidal neurons

Growth factor receptors provide a major mechanism for the activation of the nonreceptor tyrosine kinase c-Src, and this kinase in turn up-regulates the activity of N-methyl-D-aspartate (NMDA) receptors in CA1 hippocampal neurons (1). Unexpectedly, applications of platelet-derived growth factor (PDGF)-BB to cultured and isolated CA1 hippocampal neurons depressed NMDA-evoked currents. The PDGF-induced depression was blocked by a PDGF-selective tyrosine kinase inhibitor, by a selective inhibitor of phospholipase C-gamma, and by blocking the intracellular release of Ca(2+). Inhibitors of cAMP-dependent protein kinase (PKA) also eliminated the PDGF-induced depression, whereas a phosphodiesterase inhibitor enhanced it. The NMDA receptor-mediated component of excitatory synaptic currents was also inhibited by PDGF, and this inhibition was prevented by co-application of a PKA inhibitor. Src inhibitors also prevented this depression. In recordings from inside-out patches, the catalytic fragment of PKA did not itself alter NMDA single channel activity, but it blocked the up-regulation of these channels by a Src activator peptide. Thus, PDGF receptors depress NMDA channels through a Ca(2+)- and PKA-dependent inhibition of their modulation by c-Src.

Specific coupling of NMDA receptor activation to nitric oxide neurotoxicity by PSD-95 protein

The efficiency with which N-methyl-D-aspartate receptors (NMDARs) trigger intracellular signaling pathways governs neuronal plasticity, development, senescence, and disease. In cultured cortical neurons, suppressing the expression of the NMDAR scaffolding protein PSD-95 (postsynaptic density-95) selectively attenuated excitotoxicity triggered via NMDARs, but not by other glutamate or calcium ion (Ca2+) channels. NMDAR function was unaffected, because receptor expression, NMDA currents, and 45Ca2+ loading were unchanged. Suppressing PSD-95 blocked Ca2+-activated nitric oxide production by NMDARs selectively, without affecting neuronal nitric oxide synthase expression or function. Thus, PSD-95 is required for efficient coupling of NMDAR activity to nitric oxide toxicity, and imparts specificity to excitotoxic Ca2+ signaling.

G-protein-coupled receptors act via protein kinase C and Src to regulate NMDA receptors

The N-methyl-D-aspartate (NMDA) receptor contributes to synaptic plasticity in the central nervous system and is both serine-threonine and tyrosine phosphorylated. In CA1 pyramidal neurons of the hippocampus, activators of protein kinase C (PKC) as well as the G-protein-coupled receptor ligands muscarine and lysophosphatidic acid enhanced NMDA-evoked currents. Unexpectedly, this effect was blocked by inhibitors of tyrosine kinases, including a Src required sequence and an antibody selective for Src itself. In neurons from mice lacking c-Src, PKC-dependent upregulation was absent. Thus, G-protein-coupled receptors can regulate NMDA receptor function indirectly through a PKC-dependent activation of the non-receptor tyrosine kinase (Src) signaling cascade.

Regulation of N-methyl-D-aspartate receptor function by constitutively active protein kinase C

The ability of the constitutively active fragment of protein kinase C (PKM) to modulate N-methyl-D-aspartate (NMDA)-activated currents in cultured mouse hippocampal neurons and acutely isolated CA1 hippocampal neurons from postnatal rats was studied using patch-clamp techniques. The responses of two heterodimeric combinations of recombinant NMDA receptors (NR1a/NR2A and NR1a/NR2B) expressed in human embryonic kidney 293 cells were also examined. Intracellular applications of PKM potentiated NMDA-evoked currents in cultured and isolated CA1 hippocampal neurons. This potentiation was observed in the absence or presence of extracellular Ca2+ and was prevented by the coapplication of the inhibitory peptide protein kinase inhibitor(19-36). Furthermore, the PKM-induced potentiation was not a consequence of a reduction in the sensitivity of the currents to voltage-dependent blockade by extracellular Mg2+. We also found different sensitivities of the responses of recombinant NMDA receptors to the intracellular application of PKM. Some potentiation was observed with the NR1a/NR2A subunits, but none was observed with the NR1a/NR2B combination. Applications of PKM to inside-out patches taken from cultured neurons increased the probability of channel opening without changing single-channel current amplitudes or channel open times. Thus, the activation of protein kinase C is associated with potentiation of NMDA receptor function in hippocampal neurons largely through an increase in the probability of channel opening.

Multiple sites of action of neomycin, Mg2+ and spermine on the NMDA receptors of rat hippocampal CA1 pyramidal neurones

1. The effects of neomycin on NMDA-evoked currents in isolated CA1 hippocampal pyramidal neurones were investigated and single channel activity was examined in outside-out patches taken from cultured hippocampal neurones. The effects of neomycin on two combinations of NMDA receptor subunits (NR1a-NR2A and NR1a-NR2B) expressed in human embryonic kidney (HEK293) cells were also studied. 2. Neomycin (0. 01-1 mM) caused a potentiation of NMDA-activated currents in all neurones examined. No evidence of a voltage-dependent depression was observed in whole-cell recordings. 3. In outside-out patch recordings relatively low concentrations (30 and 100 microM) of neomycin caused a voltage-dependent reduction in single channel current amplitude as well as a large increase in the frequency of channel opening. 4. In saturating concentrations of glycine, neomycin enhanced NMDA-activated currents and this glycine-independent enhancement was confirmed using recombinant NR1a-NR2B receptors. Neomycin substantially increased the potency of glycine for the receptor by reducing the rate of dissociation of glycine from the receptor. Neomycin demonstrated a glycine-dependent enhancement of currents mediated by the NR1a-NR2A combination of subunits but a paradoxical depression was observed in saturating concentrations of glycine. 5. Neomycin increased the rate of deactivation of glutamate-activated currents consistent with neomycin causing a reduction in the affinity of the receptor for agonist. 6. These results indicate that neomycin has multiple and complex effects on NMDA receptors.

Vagal afferent transmission in the NTS mediating reflex responses of the rat esophagus

In urethan-anesthetized rats, esophageal distension evoked volume-dependent reflex contractions with phase-locked multiunit discharges in the central subnucleus of the solitary tract complex (NTSC) and the nucleus ambiguus. During blockade of solitarial, but not peripheral, muscarinic cholinoceptors, the volume-response relationship of reflex contractions was shifted rightward with a depression in pressure wave amplitude. Concurrently, premotor NTSC responses were attenuated and nucleus ambiguus activity was abolished during esophagomotor inhibition. Both NTSC discharges and reflex responses were eliminated, or strongly inhibited, during blockade of excitatory amino acid receptors (EAARs) with 6-cyano-7-nitroquinoxaline-2,3-dione, gamma-glutamylglycine or 2-amino-7-phosphonoheptanoate. In brain stem slice preparations, whole cell recordings in the NTSC region revealed fast excitatory postsynaptic potentials (EPSPS) with spikes in response to electrical stimulation of the solitary tract. Although spiking was facilitated by muscarine, EPSPS were resistant to cholinoceptor antagonists but sensitive to EAAR blockers. We conclude that esophageal vagal afferents excite ipsilateral NTSC interneurons via activation of glutamate receptors of the DL-alpha-amino-3-hydroxy-5-methylisoxazole-propionic acid and N-methyl-D-aspartate subtypes. Cholinergic input to the NTSC probably derives from propriobulbar sources and serves to modulate the responsiveness of reflex interneurons.

Vagovagal reflex motility patterns of the rat esophagus

Esophageal reflex motility and its neural correlates were investigated in 94 urethan-anesthetized adult male albino rats. When distended by means of a stationary balloon, the cervical and thoracic esophageal portion responded with a single pressure wave (type I response), whereas the diaphragmatic (intercrural) segment exhibited rhythmic contractions (type II response). Balloon deflation resulted in an off response aboral to the balloon. Bilateral cervical vagotomy or systemic D-tubocurarine abolished all types of reflex responses. Both type I and type II responses were associated with multiunit discharges in the central subnucleus of the solitary tract complex (NTSC) and the compact formation of the nucleus ambiguus (AMBC). Type I discharges, consisting of single bursts, and type II discharges, consisting of rhythmic 0.6-Hz bursts, preceded intraesophageal pressure waves in a fixed phase relationship, persisted after contralateral vagotomy, and were eliminated by ipsilateral vagotomy. During neuromuscular paralysis, peak intraburst discharge rates were reduced in both the NTSC and AMBC, with a concomitant decrease in rhythmicity. It is concluded that bolusevoked peristalsis of the rat esophagus is 1) segmentally organized; 2) effected by a bilateral uncrossed reflex arc consisting of vagal viscerosensory, NTSC premotor, and AMBC motoneurons innervating the striated muscle tunic and 3) strongly facilitated by reafferent feedback.

Neurotrophin modulation of NMDA receptors in cultured murine and isolated rat neurons

Neurotrophin modulation of NMDA receptors in cultured murine and isolated rat neurons. J. Neurophysiol. 78: 2363-2371, 1997. Patch-clamp and calcium imaging techniques were used to assess the acute effects of the neurotrophins, brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and nerve growth factor (NGF), on the responses of cultured and acutely isolated hippocampal and cultured striatal neurons to the glutamate receptor agonist N-methyl--aspartic acid (NMDA). The effects of BDNF on NMDA-activated currents were examined in greater detail. Currents evoked by NMDA, and the accompanying changes in intracellular calcium, were enhanced by low concentrations of the neurotrophins (1-20 ng/ml). The potentiation by the neurotrophins was rapid in onset and offset (<1 s). The neurotrophins also reduced desensitization of these currents in most cells. The enhancement of NMDA-activated currents by BDNF was observed using both perforated and whole cell patch recording techniques and could be demonstrated in outside-out patches. Furthermore, its effects were not attenuated by pretreatment with the protein kinase inhibitors genistein or 1-(5-isoquinolynesulfony)2-methylpiperazine (H7). Therefore, the actions of BDNF do not appear to be mediated by phosphorylation. Similar enhancements were observed with NT-3 and NT-4 and with NGF despite the fact that hippocampal neurons lack TrkA receptors. All together this evidence suggests that the enhancement of NMDA-evoked currents is unlikely to be mediated through the activation of growth factor receptors. Modulation of NMDA responses by BDNF was dependent on the concentration of extracellular glycine. The most pronounced potentiation by BDNF was observed at low concentrations, whereas no potentiation was observed in saturating concentrations of glycine, suggesting that BDNF may have increased the affinity of the NMDA receptor for glycine. However, the competitive glycine-site antagonist 7-chloro-kynurenic acid blocked the enhancement by BDNF without shifting the dose-inhibition relationship for this antagonist, and Mg2+ consistently depressed the potentiation of NMDA-evoked currents by BDNF, indicating that BDNF does not alter glycine affinity. BDNF also reversibly increased the probability of opening of NMDA channels recorded from outside-out patches taken from cultured hippocampal neurons. Other unrelated peptides including dynorphin and somatostatin also caused a glycine-dependent enhancement of NMDA currents and depressed the currents in saturating concentrations of glycine. In contrast, a shortened analogue dynorphin (6-17), which lacks N-terminus glycine residues, and another peptide met-enkephalin were without effects on NMDA currents recorded in low concentrations of glycine. Our results suggest that neurotrophins and other peptides can serve as glycine-like ligands for the NMDA receptor.

Recruitment of functional GABA(A) receptors to postsynaptic domains by insulin

Modification of synaptic strength in the mammalian central nervous system (CNS) occurs at both pre- and postsynaptic sites. However, because postsynaptic receptors are likely to be saturated by released transmitter, an increase in the number of active postsynaptic receptors may be a more efficient way of strengthening synaptic efficacy. But there has been no evidence for a rapid recruitment of neurotransmitter receptors to the postsynaptic membrane in the CNS. Here we report that insulin causes the type A gamma-aminobutyric acid (GABA[A]) receptor, the principal receptor that mediates synaptic inhibition in the CNS, to translocate rapidly from the intracellular compartment to the plasma membrane in transfected HEK 293 cells, and that this relocation requires the beta2 subunit of the GABA(A) receptor. In CNS neurons, insulin increases the expression of GABA(A) receptors on the postsynaptic and dendritic membranes. We found that insulin increases the number of functional postsynaptic GABA(A) receptors, thereby increasing the amplitude of the GABA(A)-receptor-mediated miniature inhibitory postsynaptic currents (mIPSCs) without altering their time course. These results provide evidence for a rapid recruitment of functional receptors to the postsynaptic plasma membrane, suggesting a fundamental mechanism for the generation of synaptic plasticity.

A review of stress ulcer prophylaxis in the neurosurgical intensive care unit

STRESS ULCERS OCCUR frequently in intensive care unit patients who have intracranial disease. After major physiological stress, endoscopic evidence of mucosal lesions of the gastrointestinal tract appears within 24 hours of injury; 17% of these erosions progress to clinically significant bleeding. Gastrointestinal hemorrhage has been associated with mortality rates of up to 50%. The pathogenesis of stress ulcers may not be completely understood, but gastric acid and pepsin appear to play significant roles. Antacids, H2 antagonists, and sucralfate are effective prophylactic agents in the medical/surgical intensive care unit. Appropriate therapy for neurosurgical patients remains unclear, however. This review summarizes the current literature regarding the pathogenesis and therapy of stress ulcers in neurosurgical patients.

Clarification of an uncertain intron within the cDNA sequences of arrowhead proteinase inhibitors A and B

An uncertain intron of 87 bp within the cDNA sequences of arrowhead proteinase inhibitors A and B was clarified. By site-directed mutation with either a stop codon inside the uncertain intron or mutated codons at both its 5' and 3' ends, it was proved that there was neither a translation intron nor a protein intron present in the cDNA sequences of proteinase inhibitors A and B. The primary structure of inhibitor B was then reexamined by mass spectrometry molecular weight determination and partial amino acid sequencing. A 38 residue peptide was derived by degradation of inhibitor B with lysylendopeptidase, and purified, which was not found in the previous work, and its N-terminal part was none other than the missed 29 residue peptide encoded by the uncertain intron. The 38 residue peptide was very hydrophobic, while the 29 residue peptide it included was even more hydrophobic. The N-terminal part of the missed peptide was also aligned within a BrCN-degraded fragment of the inhibitor. In this paper the cause of the overlooking of this 29 residue peptide in the previous work and some unexpected problems which arose during the former sequence analysis are explained.

A step-wise protocol for stress ulcer prophylaxis in the neurosurgical intensive care unit

BACKGROUND

Neurosurgical patients are at risk for stress induced gastric erosion. Clinical criteria for monitoring stress ulcer prophylaxis (SUP) efficacy and predicting clinical bleeding are limited. SUP in the neurosurgical intensive care unit (NSICU) was evaluated utilizing a multidisciplinary quality assurance program with defined criteria for therapy.

METHODS

All patients admitted to the NSICU were managed using this protocol. Therapy was initiated with a single drug (cimetidine 300 mg IV every 6 hours, or continuous infusion up to 2400 mg/day) in 136 evaluable cases. Combination therapy was implemented if continued gastric pH < 4 and guaiac positive aspirates occurred (N = 45).

RESULTS

Significant correlations were observed between low gastric pH values and both GCS < 8 (P < or = 0.01) and length of ventilatory support (P < or = 0.005). Single agent therapy was more effective in patients with GCS > or = 8 (P < or = 0.001). Endoscopy was performed in 25 patients. No patient with GCS < 8 had pathologic lesions. The presence of asymptomatic gastrointestinal lesions was higher in patients requiring longer ventilatory support (P < or = 0.001) and intensive care unit stay (P < or = 0.0001). Patients requiring pentobarbital and vasopressors had statistically higher rates of clinical bleeding (P < 0.05). Patients with GCS < 8 had increased rates of pneumonia (P < or = 0.005) with a higher pneumonia rate when treated with combination therapy (P < or = 0.05). Overall, the incidence of clinical bleeding was 3.7%.

CONCLUSIONS

This protocol was effective for prospective monitoring of SUP efficacy and limited multiple drug therapy to patients at risk for clinical bleeding.

Inhibition of nicotinic cholinoceptor mediated current in vagal motor neurons by local anesthetics

The effects of local anesthetics on ligand-gated cation channel currents were examined in rat brainstem vagal motoneurons. Etidocaine (0.1-20 microM) blocked nicotinic cholinoceptor gated currents in cells voltage-clamped at -60 mV in a concentration-dependent manner, but at concentrations up to 100 microM did not inhibit glutamate receptor currents induced by (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA), N-methyl-D-aspartate (NMDA), or glutamate. Relative to etidocaine, procaine displayed about 10-fold lower potency in antagonizing acetylcholine and its inhibitory effect, unlike that of etidocaine, was rapidly reversed by washout. Ketamine (10 microM) caused a 2-fold larger decrease in NMDA current than acetylcholine current, but did not affect AMPA current. In conclusion, (i) etidocaine and procaine possess a moderately potent blocking activity at nicotinic cholinoceptor gated channels in brainstem vagal motoneurons and (ii) in contrast with ketamine, both agents showed similar selectivity in that neither inhibited glutamate receptor gated channels at concentrations up to 0.1 mM.

[Target therapy by monoclonal antibody against ovarian carcinoma conjugated with liposomes and adriamycin]

Conjugates of monoclonal antibody COC166-9 and adriamycin entrapped in liposome (MLA) were prepared in our laboratory. In vitro growth inhibition of SKOV3 ovarian carcinoma cell line was carried out by MLA and controls. Target therapies by MLA, adriamycin, normal mouse IgG instead of MAb, and control were given for 24 nude mice models with subcutaneous human ovarian carcinoma xenografts and 16 ascitic ovarian carcinoma respectively. MLA group showed the best therapeutic effect than all the other groups which gave a helpful clue to clinical use.

[Target therapy by monoclonal antibody against ovarian carcinoma conjugated with liposome and adriamycin]

Conjugates of monoclonal antibody (MAb) and adriamycin entrapped in liposome (MLA) were prepared by COC166-9. The MAb against ovarian serous adenocarcinoma was generated in our laboratory. Target therapies were done in nude mice model with subcutaneous tumor xenografts in 24 and ascitic carcinoma in 16 by MLA. The results demonstrated that MLA group presented the best therapeutic effect than all the other groups, which gave a very helpful clue to clinical target therapy of ovarian carcinoma in the future.

Anti-idiotypic monoclonal antibodies against anti-ovarian carcinoma monoclonal antibody COC166-9. Generation and application

Anti-idiotypic monoclonal antibody (Mab Ab2) by MAb COC166-9 against ovarian serous papillary adenocarcinoma was prepared. Hybridomas of Ab2 screened by sandwich ELISA and immunocompetitive inhibition tests were procured and named as 6B11 and 1H12. The number of their chromosomes were 93 and 91, and DNA analysis also proved the characteristics of hybridomas. These Ab2s could induce delayed type hypersensitivity (DTH), the cellular immune response. The results of the immune reaction of 6B11 with SKOV3 (ovarian carcinoma cell line) were similar to OC166-9 (Ag), the positive control, while 1H12 was weaker. Anti-anti-idiotypic antibody (Ab3) was also raised by 6B11 and 1H12 respectively. They all showed positive immunohistochemical stainings with ovarian serous adenocarcinoma tissue sections and immunocytochemical stainings with SKOV3 cells as was shown by COC166-9. In the antibody dependent cell mediated cytotoxicity (ADCC) tests, they showed no differences against SKOV3 as compared with COC166-9. We anticipate that 6B11 and 1H12 may be used as vaccines against ovarian carcinoma and may provide a clue for its prevention and treatment.

[The induction of specific immunity to human ovarian carcinoma cells by anti-idiotypic antibodies]

Monoclonal anti-idiotypic antibodies, 6B11 and H12, were employed instead of the tumor antigen to induce a specific cellular immunity to ovarian carcinoma cell line SKOV3. 6B11 and 1H12 carring the internal image of ovarian carcinoma antigen. BALB/c mice were immunized with 6B11 or 1H12 and then the mouse foot pad was attacked by the injection of target cell SKOV3 to stimulate a specific delayed-type hypersensitivity (DTH). The results showed that 6B11 induced a severe foot pad swelling (Mean thickness 0.93mm) as seen in the positive control (P > 0.05) induced by ovarian carcinoma antigen; the 1H12 induced swelling was significantly lower than the positive control (P < 0.05). Both 6B11 and 1H12 expressed the effective responses only to SKOV3, but not to the unrelated target cells. Pathological examinations found that there was marked infiltration of inflammatory cells in foot pad of mice primed by 6B11, while by 1H12, only induced a narrow pathological changes. These observations indicated that there would be some essential differences between 6B11 and 1H12 in the behavior of inducing the specific DTH to SKOK3. And as an idiotypic vaccine, 6B11 would be more powerful against ovarian carcinoma.

[Antigen mimicry of anti-idiotypic antibodies for human ovarian carcinoma antigen: generation and characterization of anti anti-idiotype antibodies]

The antigen mimicry of monoclonal anti-idiotypic antibodies 6B11 and 1H12 was investigated, which carrying the internal image of human ovarian carcinoma antigen. Anti-anti-idiotypic antibodies, obtained from the mice immunized with 6B11 or 1H12, binded to ovarian tumor antigen OC 166-9 specifically by enzyme linked immunosorbent assay (ELISA). Western blot analysis showed that Ab3 and Ab1 recognized the same antigenic protein. Through antibody dependent cell-mediated cytotoxicity (ADCC), Ab3 sera killed the ovarian carcinoma cell line SKOV3 specifically in vitro. These results suggest that 6B11 and 1H12 may substitute for the nominal antigen to stimulate a specific immune response and that they are potential candidates as idiotype vaccines against ovarian carcinomas.