Effect of SstI polymorphism of the apolipoprotein CIII gene and environmental factors on risks of hypertriglyceridemia in Taiwan aborigines

BACKGROUND

Hypertriglyceridemia (HTG) is a heterogeneous metabolic disorder. The aim of this study was to examine associations among genetic polymorphisms, SstI polymorphism of apolipoprotein CIII (ApoCIII) and Hind III polymorphism of lipoprotein lipase (LPL), environmental factors and risks of HTG.

METHODS AND RESULTS

Two hundred and forty-nine southern Taiwanese aborigines were recruited for a cross-sectional study, which included 90 subjects with triglyceride (TG)>150 mg/dl (HTG) and 159 with TG<or=150 mg/dl (NTG). The frequencies of SstI major allele (S1) and minor allele (S2) of ApoCIII were 66.1% and 33.9% in HTG and 73.6% and 26.4% in NTG (p<0.1). In female subjects, the frequencies of the S2 allele was significantly higher in HTG (0.38) than NTG (0.27) (p<0.04). The frequencies of the LPL HindIII major allele (H+) and minor allele (H-) were similar between HTG (H+ 84.3%; H- 15.7%) and NTG (H+ 78.9%; H- 21.1%). In a multivariate adjusted logistic model, education<or=6 year (odds ratio (OR)=3.71, 95% confidence interval (CI): 1.24-8.13), Amis tribe (OR=3.08, 95% CI: 1.41-6.77), body mass index (BMI)>or=25 (OR=2.22, 95% CI: 1.18-4.16), starchy food consumption>or=3 times/week (OR=1.89, 95% CI: 1.00-3.59) and ApoCIII S2S2 genotype (OR=3.35, 95% CI: 1.10-10.19) were independently (p<0.05) associated with HTG risks. Among ApoCIII S1S1, S1S2 and S2S2 genotypes, ApoCIII and TG concentrations increased (p<0.01) in a dose-responsive manner.

CONCLUSIONS

The ApoCIII S2 variant and environmental factors, including education, tribal background, BMI and starchy food intake, modulate the risks of HTG in aboriginal Taiwanese. Interaction between genetic and environmental factors warrants further investigation.

Contribution of somatic cell-associated activation of plasminogen to caseinolysis within the goat mammary gland

Functional regression of the mammary gland is partly reflected by proteolysis of milk protein and tissue protein. The involvement of the plasminogen activation system in degradation of milk protein and mammary tissue damage has been demonstrated under inflammatory conditions. In this study, mammary secretion from 23 dairy goats primarily grouped as lactation (milking twice daily) or involution (milking once daily or less) was used to determine the ratio of gravity-precipitated casein to total milk protein (casein ratio) as an index of caseinolysis, and activities of components of plasminogen activation system as well as their expressions on somatic cells. Based on the casein ratio, lactation goats were subcategorized as very active (71.8 +/- 1.0%) or less active (29.9 +/- 1.0%) in mammary function; involution goats were subcategorized as gradual (21.7 +/- 1.0%) or acute (5.9 +/- 0.2%) involution. This result suggests that caseinolysis occurred during regular lactation as well as during involution. On the other hand, activities of components of the plasminogen activation system in mammary secretion were increased along with the decreasing casein ratio, in contrast to the similar activities of their counterparts in circulation throughout various mammary statuses. Correlation analysis between casein ratio and activities of plasminogen activation system of goat milk indicated a significant negative relationship for plasmin (r = -0.64), plasminogen (r = -0.69), and urokinase-type plasminogen activator (uPA; r = -0.78) during involution but not during lactation. As for the cellular components of plasminogen activation system, there was an increase in immunoreactivity on somatic cells toward both monoclonal antibodies of human uPA and human uPA receptor under involution conditions suggesting their upregulation relative to lactation condition. Collectively, these results suggest that plasminogen activation system within the mammary gland differentially contribute to milk caseinolysis along the various stages of goat lactation. Meanwhile, a somatic cell-mediated local elevation of plasmin activity may be committed to extensive caseinolysis during involution.

Successful outpatient treatment of renal vein thrombosis by low-molecular weight heparins in 3 patients with nephrotic syndrome

Renal vein thrombosis (RV Thromb) is a serious complication ofnephrotic syndrome. Anticoagulation is usually recommended as the treatment of choice. This study reports 3 nephrotic patients diagnosed to have RVThromb combined with thromboembolic events. Low-molecular weight heparin (LMWHep) was given subcutaneously every 12 hours following the diagnosis of RVTromb, which continued at the outpatient clinic after an average of 11 in-hospital days. The patients visited the nephrology outpatient clinic every other week and underwent magnetic resonance image (MRI) studies at 6-week intervals for follow-up of patency of the involved renal vein. LMWHep was discontinued when MRI showed this patency. The average outpatient treatment period was 74 days. There was no recurrent RVThromb in the follow-up course of 6 months after discontinuation of LMWHep. Kidney function was preserved, as indicated by image studies and serial renal function tests. LMWHep produced a more predictable anti-coagulant effect, a superior bioavailability, a longer half-life and a dose-independent effect than unfractionated heparin and coumadin. These benefits made the outpatient treatment of RVThromb possible. Our report recommends outpatient treatment of RVThromb by LMWHep because it is feasible, effective and safe.

G-2548A polymorphism of the leptin gene is correlated with extreme obesity in Taiwanese aborigines

We examined the genetic associations of the G-2548A polymorphism in the promoter of the leptin (LEP) gene and the Gln223Arg (Q223R) polymorphism of the leptin receptor (LEPR) gene with obesity. Two hundred twenty-six obese aboriginal subjects (BMI > or = 27 kg/m2) and 182 aboriginal subjects with normal weight (BMI < 25 kg/m2) participated in this study. The polymorphisms of LEP G-2548A and LEPR Q223R were genotyped by polymerase chain reaction/restriction fragment length polymorphism, and their anthropometric characteristics were measured. Levels of leptin, triglycerides, and cholesterol were measured after overnight fasting. We found that the frequencies of the LEP G/G homozygote (22.6%) with Mendelian recessive (chi2 = 7.89, p = 0.005) and codominant (chi2 = 7.93, p = 0.02) models to be higher in the extremely obese subjects (BMI > or = 35 kg/m2) than in normal weight subjects (6.9%) but not in moderately obese subjects (35 > BMI > or = 27 kg/m2). There was no difference in genotypic frequency of the LEPR Q223R polymorphism between the extreme obese and control groups. We suggest that the LEP -2548 G/G homozygote plays a genetic recessive role in the development of extreme obesity in Taiwanese aborigines.

Prevalence and risk factors associated with dyslipidaemia in children and adolescents among ethnic groups in Taiwan

BACKGROUND

The mortality rates of cerebral and cardiovascular diseases are higher for aborigines than non-aborigines in Taiwan. Hypertriglyceridaemia and hypercholestolaemia are risk factors for cardiovascular diseases.

OBJECTIVES

To investigate the prevalence of dyslipidaemia and its associated risk factors in aborigine (Atayal, Paiwan and Bunun tribes) and non-aborigine (Fukein and Hakka Chinese) children and adolescents in Taiwan.

STUDY DESIGN

This was a cross-sectional study.

METHODS

In total, 718 males and 721 females, below 20 years of age, were recruited. Our study defined dyslipidaemia as serum triglyceride and cholesterol levels greater than 200 and 240 mg/dl, respectively.

RESULTS

The serum triglyceride level and the prevalence of hypertriglyceridaemia were similar in both aborigines and non-aborigines and both sexes, but the Bunun and Paiwan tribes had the highest prevalence of hypertriglyceridaemia in males (11.8-29.4%) and females (10.9-22.8%) compared with other aboriginal tribes (5.1-10.8% for males and 7.8-9.2% for females). Serum cholesterol concentrations and the prevalence of hypercholesterolaemia were lower in the aborigines than non-aborigines for both sexes (P<0.05), with the Atayal tribe having the lowest prevalence in males (1.1%) and females (2.1%) compared with other aboriginal tribes (2.4-4.5% for males and 5.7-8.0% for females). Using multivariate-adjusted logistic regression modelling, hypertriglyceridaemia was significantly associated with the Bunun tribe (odds ratio (OR)=3.2, 95% confidence intervals (CI) 1.6-6.1), hyperuricaemia (OR=1.8, 95% CI 1.2-2.6), hypercholesterolaemia (OR=3.3, 95% CI 1.7-6.4) and alcohol use (OR=2.8, 95% CI 1.2-6.6). Hypercholesterolaemia, after controlling for age and sex, was significantly associated with the Atayal tribe (OR=0.2, 95% CI 0.1-0.5), hypertriglyceridaemia (OR=3.5, 95% CI 1.8-6.7) and hyperuricaemia (OR=3.2, 95% CI=1.7-6.0).

CONCLUSIONS

For the young people of Taiwan, hypertriglyceridaemia is associated with hyperuricaemia, hypercholesterolaemia and alcohol use, and hypercholesterolaemia is associated with hypertriglyceridaemia and hyperuricaemia. Compared with non-aborigines, the young aborigines of some tribes have a higher prevalence of hypertriglyceridaemia and a lower serum cholesterol level.

Independent and combined effects of alcohol intake, tobacco smoking and betel quid chewing on the risk of esophageal cancer in Taiwan

A multicenter case-control study was conducted in northern and southern Taiwan to clarify the independent and combined effects of alcohol intake, tobacco smoking and betel quid chewing on the risk of esophageal cancer. A total of 513 patients with newly diagnosed and histopathologically confirmed squamous cell carcinoma of the esophagus and 818 gender, age and study hospital-matched controls were included. We found a significant dose-response relationship between the duration and intensity of consumption of the 3 substances and the development of this neoplasm in this site. Although the amount of alcohol consumed had a stronger effect on the risk of esophageal cancer than the number of years it was consumed, however, the number of years one smoked had a stronger effect on the risk than the amount of cigarettes consumed. The strongest risk factor of esophageal cancer was alcohol intake, with highest risk (OR = 13.9) being for those who consumed more than 900 g/day-year. Combined exposure to any 2 of 3 substances brought the risks up to 8.8-19.7 fold and, to all 3 substances, to 41.2-fold. A multiplicative interaction effect for alcohol drinkers who smoked on cancer risk was detected, whereas an additive interaction effect was found among drinkers who chewed. The combined effect of all 3 substances accounted for 83.7% of the attributable fraction of contracting esophageal cancer in this population. In conclusion, these results suggest that the intensity and the length of time alcohol and tobacco are used play different roles in the etiology of esophageal cancer. Alcohol separately interacts with tobacco and betel quid in a differently synergistic way in determining the development of this site of cancer.

Influence of surgeon volume on clinical and economic outcomes of laparoscopic cholecystectomy

BACKGROUND AND PURPOSE

The volume-outcome effect has been well documented in both medical treatment and surgery. The relationship of volume-outcome utilization in laparoscopic cholecystectomy has not been studied. The aims of this study were to examine whether the operational volume of individual surgeons is associated with the clinical and economic outcomes of patients with gallbladder diseases undergoing laparoscopic cholecystectomy.

METHODS

A retrospective study was made of all patients who underwent elective laparoscopic cholecystectomy in the Department of Surgery, Kaohsiung Medical University Hospital between January 1998 and April 2002. In total, 916 patients were operated on by 4 surgeons and the volume for each surgeon was 502, 192, 147, and 75 cases, respectively. Clinical and economic information for each patient was abstracted from medical charts and the financial division. Multiple logistic and linear regression models were used to examine the relationship between three outcome variables, complications, length of stay, total hospital charges, and surgeon volume while controlling for the severity of illness and other selected covariates (morbidity index).

RESULTS

Overall, a complication rate of 1.2% was identified. On average, the patient's stay in hospital was 4.7 days, and the average total hospital charge was TWD 49,581. After adjusting for covariates, three regression models indicated that the surgeon with the highest volume had the lowest complication rate, shortest length of stay, and lowest hospital charges.

CONCLUSIONS

The operative volume of individual surgeons not only had a positive impact on clinical outcomes, it also had greater effect on conservation of health care resources. The findings validate the theory of practice makes perfect.

Association between diet and esophageal cancer in Taiwan

BACKGROUND

Several studies have reported the importance of dietary factors in the development of esophageal cancer. The purpose of the present study was to evaluate the effects of several common dietary factors on the risk of squamous cell carcinoma of the esophagus in a Taiwanese population.

METHODS

The association between diet and esophageal cancer was examined in 284 male patients and 480 male controls, who were recruited during 6 year period.

RESULTS

Consumption of preserved and overheated foods was found to be associated with increased risk of esophageal cancer, whereas intake of fresh fruits, vegetables, and tea was inversely associated with this risk. Men who consumed fermented bean products, salted food and preserved/pickled vegetables more than once a week after age 40 years had a 3.4-fold risk (95% confidence interval (CI): 1.9-6.2), 2.3-fold risk (95%CI: 1.2-4.2), and 2.5-fold risk (95%CI: 1.3-4.5), respectively, compared to men eating these items less than once a week. It was further found that these preserved foods were more strongly associated with esophageal cancer among men who consumed fruit less than once per day than those who consumed fruits one or more times per day.

CONCLUSIONS

These results suggest that a high intake of preserved foods and overheated drinks might increase the risk of esophageal cancer, and intake of fruit, vegetables, and tea might be negatively associated with risk of esophageal cancer. The results also suggest that diet is an important factor in the development of esophageal cancer in Taiwan.

Challenges of assuring crew safety in space shuttle missions with international cargoes

The top priority in America's manned space flight program is the assurance of crew and vehicle safety. This priority gained greater focus during and after the Space Shuttle return-to-flight mission (STS-26). One of the interesting challenges has been to assure crew safety and adequate protection of the Space Shuttle, as a national resource, from increasingly diverse cargoes and operations. The control of hazards associated with the deployment of complex payloads and cargoes has involved many international participants. These challenges are examined in some detail along with examples of how crew safety has evolved in the manned space program and how the international partners have addressed various scenarios involving control and mitigation of potential hazards to crew and vehicle safety.

Effects of Glucose Concentration on in vitro Fertilization in BALB/c Mice

BALB/c mice are widely used in genetic, tumour and immunological studies. However, the mice demonstrate a lower reproduction rate, low fertility and small litters, because of their highly genetic homozygoisty. Based on in vitro fertilization (IVF), a routine technique for biomedical studies, it is worth to evaluate the effects to BALB/c mice on IVF efficiency. In order to test the genetic factor affecting the IVF efficiency of BALB/c, four reciprocal IVF tests of BALB/cByJ and FVB/NCrl mice were performed. The results showed that the average fertility of IVF sponsored by FVB/NCrl spermatozoa was 69.6%, but only 12.1% was obtained from BALB/cByJ strain. Effect of glucose contained in the culture medium to the IVF efficiency of BALB/cByJ was also evaluated. The results showed that the fertility of BALB/cByJ spermatozoa incubated with 0, 2.7, 5.5, 11.1 and 22.2 mm of glucose in the TYH medium were 6.8, 9.9, 13.9, 32.7 and 22.2%, respectively. It is showed that IVF efficiency of BALB/cByJ spermatozoa could be improved depending on the concentration of glucose in the IVF medium. According to the results, it is beleived that lower IVF of BALB/cByJ mice might be due to the genetic defect in spermatozoa and increasing glucose in the IVF medium which significantly affect the IVF efficiency of BALB/cByl via activating the spermatozoa.

Long chain polyunsaturate supplementation does not induce excess lipid peroxidation of piglet tissues

BACKGROUND

Addition of highly polyunsaturated fatty acids to infant formulas raises the possibility of increased lipid peroxidation.

AIM OF THE STUDY

We determined the effects of increasing levels of dietary docosahexaenoic acid (DHA) and arachidonic acid (AA) on lipid peroxidation and peroxidative potential in piglet tissues.

METHODS

Four groups of piglets (n = 6) were bottle-fed a formula containing one of four treatments: no long chain fatty acid (Diet 0) and three different levels of DHA/AA at 1-fold (0.3 %/0.6% FA; Diet 1) 2-fold (0.6 %/1.2% FA; Diet 2) and 5-fold (1.5%/3% FA; Diet 5) concentration used in some human infant formulas, and all with equal amount of vitamin E (5.7 IU/ 100 kcal formula) for four weeks.

RESULTS

There were no significant differences between the groups in conjugated diene and glutathione (GSH) levels in the liver, and thiobarbituric acid-reactive substance (TBARS) in plasma. TBARS levels of the erythrocyte membranes increased in a dose-dependent manner when in vitro oxidation was induced with 10 mM hydrogen peroxide (H(2)O(2)) for 30 minutes. The TBARS levels of the liver homogenates of the Diet 5 and Diet 2 groups were significantly different than those of the membranes of the Diet 0 group when the in vitro oxidation was induced with H(2)O(2).

CONCLUSION

The results show that dietary vitamin E effectively prevented lipid peroxidation at the LCP concentrations investigated and suggest that levels presently in infant formulas are sufficient.

Comparative analyses of multi-species sequences from targeted genomic regions

The systematic comparison of genomic sequences from different organisms represents a central focus of contemporary genome analysis. Comparative analyses of vertebrate sequences can identify coding and conserved non-coding regions, including regulatory elements, and provide insight into the forces that have rendered modern-day genomes. As a complement to whole-genome sequencing efforts, we are sequencing and comparing targeted genomic regions in multiple, evolutionarily diverse vertebrates. Here we report the generation and analysis of over 12 megabases (Mb) of sequence from 12 species, all derived from the genomic region orthologous to a segment of about 1.8 Mb on human chromosome 7 containing ten genes, including the gene mutated in cystic fibrosis. These sequences show conservation reflecting both functional constraints and the neutral mutational events that shaped this genomic region. In particular, we identify substantial numbers of conserved non-coding segments beyond those previously identified experimentally, most of which are not detectable by pair-wise sequence comparisons alone. Analysis of transposable element insertions highlights the variation in genome dynamics among these species and confirms the placement of rodents as a sister group to the primates.

Female-specific DNA sequences in geese

1. The OPAE random primers (Operon Technologies, Inc., CA) were used for random amplified polymorphic DNA (RAPD) fingerprinting in Chinese, White Roman and Landaise geese. One of these primers, OPAE-06, produced a 938-bp sex-specific fragment in all females and in no males of Chinese geese only. 2. A novel female-specific DNA sequence in Chinese goose was cloned and sequenced. Two primers, CGSex-F and CGSex-R, were designed in order to amplify a 912-bp sex-specific polymerase chain reaction (PCR) fragment on genomic DNA from female geese. 3. It was shown that a simple and effective PCR-based sexing technique could be used in the three goose breeds studied. 4. Nucleotide sequencing of the sex-specific fragments in White Roman and Landaise geese was performed and sequence differences were observed among these three breeds.

Negligible changes in piglet serum clinical indicators or organ weights due to dietary single-cell long-chain polyunsaturated oils

Single-cell oils are currently included in human infant formula as sources of the long-chain polyunsaturates (LCP) docosahexaenoic acid (DHA) and arachidonic acid (AA) in many countries, but have not yet been approved for use in the USA. We prepared four bovine-milk-based formulas with AA/DHA=0, 34/17, 68/34 and 170/85 (mg per 100 kcal formula) provided by two commercial single-cell oils. These levels correspond approximately to 0, 1, 2 and 5 times the concentrations used in infant formulas and, due to greater consumption of formula per unit body weight, resulted in daily consumption of approximately 0, 3, 6 and 16 times those anticipated for human infants. All other dietary fat (47% of calories) was provided by a vegetable oil blend used in commercial human infant formulas. Domestic piglets were allowed to nurse with the sow for 24 h after parturition, then removed to individual cages and maintained on one of the four diets. At 30 days of age the piglets were sacrificed, and serum collected and organs weighed. With litters treated as a blocked variable, no significant differences among groups were found by analysis of variance for the following serum assays: alkaline phosphatase, alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatinine, albumin, glucose, cholesterol, triglycerides, and total protein. No significant differences were found for hematocrit or body weight. No significant differences were found among groups for weights of liver, brain, heart, lung, spleen, kidneys or lung, analyzed as absolute weight and as a fraction of body weight. Hematoxylin/eosin liver sections examined by light microscopy showed no abnormalities as evaluated by an independent pathologist. DHA content in liver and heart and AA content in heart showed significant dose-related accumulation (P<0.05) and confirmed enhanced tissue accretion of DHA and AA from both oils. We conclude that single-cell oils in formula consumed for 1 month in amounts up to 16-fold greater than proposed for human infants in the USA did not result in clinical chemistry or histopathologic indications of toxic effects in neonatal pigs.

Efficacy of dietary arachidonic acid provided as triglyceride or phospholipid as substrates for brain arachidonic acid accretion in baboon neonates

Arachidonic acid (AA) is a long-chain polyunsaturate (LCP) present in human breast milk as both triglyceride (TG) and as phospholipid (PL). There has been little attention to the metabolic consequences of lipid form of AA in infant formulas. Our objective was to investigate the efficacy of dietary TG and PL as carriers of AA for accretion in the brain and associated organs of term baboon neonates consuming a formula with LCP composition typical of human milk. TG and phosphatidylcholine (PC) with [U-(13)C]-AA in the sn-2 position and with unlabeled 16:0 in the remaining positions (TG-AA* or PL-AA*, respectively) were used as tracers to study the tissue AA* incorporation. Baboon neonates received a single oral dose of either TG-AA* (n = 3) or PL-AA* (n = 4) at 18-19 d of life. Tissues were obtained 10 d later (28-29 d of life) and isotopic enrichment was measured. In the brain, 4.5% of the PL-AA* dose and 2.1% of the TG-AA* dose were recovered as brain AA*, respectively, indicating that PL was about 2.1-fold more effective than TG as a substrate for brain AA accretion. Preferential incorporation of PL-derived AA* over TG source of AA* was also observed in the liver, lung, plasma, and erythrocytes. Because of the quantitative predominance of TG-AA in formula, total brain AA accretion, expressed as absolute weight, was 5.0-fold greater from TG-AA than from PL-AA. We estimate that about half of postnatal brain AA accretion is derived from dietary preformed AA in term baboon neonates consuming a formula with lipid composition similar to that of human milk.

Development of a high-performance liquid chromatographic method for bioanalytical applications with sulpiride

An improved HPLC method using a silica gel column with fluorescence detection (excitation at 300 nm and emission at 365 nm) was developed for the determination of sulpiride concentrations in plasma. Analysis of sulpiride in plasma samples was simplified by a one-step liquid-liquid extraction after alkaline treatment of only 1 ml of plasma. The low limit of quantitation was 20 ng/ml with a coefficient of variation of less than 20%. A linear range was found from 20 to 1500 ng/ml. This HPLC method was validated with the precision for inter-day and intra-day runs being 0.36-8.01% and 0.29-5.25%, respectively, and the accuracy (standard deviation of mean, SD) for inter-day and intra-day runs being -1.58 to 5.02% and -2.14 to 5.21%, respectively. Bioequivalence of the two products was evaluated in 12 normal healthy male volunteers in a single-dose, two-period, two-sequence, two-treatment cross-over study. Sulpiride plasma concentrations were analyzed with this validated HPLC method. Results demonstrated that the two tablet formulations of sulpiride appear to be bioequivalent.

Repeated ingestion of grapefruit juice does not alter clozapine's steady-state plasma levels, effectiveness, and tolerability

BACKGROUND

Grapefruit juice can inhibit the gastrointestinal activity of cytochrome P450 (CYP) 3A4, while its effect on CYP1A2 remains controversial. Several grapefruit juice bioflavonoids also modulate the activity of the drug transporter P-glycoprotein in the gut and in the blood-brain barrier. Both CYP1A2 and CYP3A4 are involved in clozapine metabolism. This study investigated the effects of repeated ingestion of grapefruit juice on multiple-dose pharmacokinetics and pharmacodynamics of clozapine in schizophrenic patients.

METHOD

Clozapine therapy was initiated for fifteen treatment-resistant schizophrenic inpatients (DSM-IV criteria). The doses were individually titrated from day -35 to day -15 and then kept unchanged from day -14 to day 49. Regular-strength grapefruit juice (250 mL) was coadministered b.i.d. with each clozapine dose from day 15 to day 28. Plasma levels of clozapine and its main metabolites (norclozapine and clozapine N-oxide) were obtained, and clinical efficacy and safety assessments were completed prior to juice administration (days 0, 7, and 14), during the coadministration (days 17, 21, and 28), and after cessation of the juice (days 35, 42, and 49).

RESULTS

After reaching steady states, plasma concentrations of clozapine and its metabolites and Positive and Negative Syndrome Scale scores were not significantly altered by the effect of grapefruit juice ingestion. The Clinical Global Impressions scale scores, Calgary Depression Scale scores, and side effect profiles (by the Extrapyramidal Symptom Rating Scale, the UKU Side Effect Rating Scale, and thorough examinations including electrocardiography and electroencephalography) also remained constant during the study.

CONCLUSION

Consumption of regular-strength grapefruit juice, 250 mL b.i.d., for 14 days did not significantly impact clozapine metabolism, clinical efficacy, or tolerability. One reason is that enzymes other than CYP3A4 also mediate clozapine disposition. Also, grapefruit juice inhibits CYP3A4 in the gut, but not in the liver. The preliminary results also suggest that clozapine is unlikely to be a P-glycoprotein substrate. Further rigorous studies are necessary to reconfirm these findings.

Affinity, kinetics, and thermodynamics of E-selectin binding to E-selectin ligand-1

E-selectin is an endothelial adhesion molecule, which mediates the tethering and rolling of leukocytes on vascular endothelium. It recognizes the glycoprotein E-selectin ligand-1 (ESL-1) as a major binding partner on mouse myeloid cells. Using surface plasmon resonance, we measured the kinetics and affinity of binding of monomeric E-selectin to ESL-1 isolated from mouse bone marrow cells. E-selectin bound to ESL-1 with a fast dissociation rate constant of 4.6 s(-1) and a calculated association rate constant of 7.4 x 10(4) m(-1) s(-1). We determined a dissociation constant (K(d)) of 62 microm, which resembles the affinity of L-selectin binding to glycosylation-dependent cell adhesion molecule-1. The affinity of the E-selectin-ESL-1 interaction did not change significantly when the temperature was varied from 5 degrees C to 37 degrees C, indicating that the enthalpic contribution to the binding is small at physiological temperatures, and that, in contrast to typical protein-carbohydrate interactions, binding is driven primarily by favorable entropic changes. Interestingly, surface plasmon resonance experiments with recombinant ESL-1 from alpha 1,3-fucosyltransferase IV-expressing Chinese hamster ovary cells showed a very similar K(d) of 66 microm, suggesting that this fucosyltransferase is sufficient to produce fully functional recombinant ESL-1. Following the recent description of the affinity and kinetics of the selectin-ligand pairs L-selectin-glycosylation-dependent cell adhesion molecule-1 and P-selectin-P-selectin glycoprotein ligand-1, this is the first determination of the parameters of E-selectin binding to one of its naturally occurring ligands.

A metastatic pituitary carcinoid tumor successfully treated with gamma knife radiosurgery

Intracranial metastasis occurs in a certain number of patients with carcinoid tumor. However, carcinoid tumor with metastasis to the pituitary gland is extremely rare. Up to the present, no effective treatment for either a metastatic intracranial carcinoid tumor or a metastatic pituitary lesion of any origin has been documented. We have treated a case of metastatic carcinoid tumor of the pituitary gland with transsphenoidal tumor resection followed by gamma knife radiosurgery. A 59-year-old man presented with headache and left oculomotor palsy. He was treated at the same hospital for bronchial atypical carcinoid tumor one and a half years ago. Magnetic resonance image of the brain showed a pituitary tumor. There were no signs of recurrent or metastatic lesion elsewhere despite thorough investigation. Transsphenoidal approach for removal of tumor was done and the pathology turned out to be a metastatic carcinoid tumor. Subsequent gamma knife radiosurgery was given for residual tumor. The oculomotor palsy improved after radiosurgery. No neurological deficit occurred. Follow-up CT scan of the brain showed complete resolution of the tumor. We concluded that gamma knife radiosurgery could be used to treat a metastatic intracranial carcinoid tumor. It can also be used to treat a metastatic lesion of the pituitary gland without causing neurological deficit.

Loss of mismatch repair activity in simian virus 40 large T antigen-immortalized BPH-1 human prostatic epithelial cell line

Simian virus 40 large T antigen (SVLTAg) has been used to immortalize cells; however, the mechanism leading to immortalization is still unclear. We hypothesize that DNA mismatch repair (MMR) activity is important during SVLTAg-induced immortalization. To test this hypothesis, we used the SVLTAg-immortalized cell line BPH-1 derived from human benign prostate epithelial cells to analyze MMR activity and the expression of MMR genes (hMLH1, hPMS1, hPMS2, hMSH2, hMSH3, and hMSH6). The results demonstrated that BPH-1 cells were deficient in repairing G:T, A:C, and G:G mispairs in bacteriophage M13mp2. Reverse-transcription polymerase chain reaction experiments indicated MMR genes (hMSH3, hMSH6, and hPMS1) were expressed at a low level in BPH-1 cells. In contrast, all six MMR genes were expressed in human benign prostate hyperplasia tissues. Downregulation of hMSH3, hMSH6, and hPMS1 genes is not a result of the hypermethylation mechanism because demethylation with 5-aza-2'-deoxycytidine did not restore expression of these genes. Although the hMLH1 gene is expressed in BPH-1 cells, western blotting and exon analyses demonstrated that hMLH1 was mutated and/or deleted in BPH-1 cells.

Creation and activity of COS-1 cells stably expressing the F2 fusion of the human cholesterol side-chain cleavage enzyme system

A fusion construct for the human cholesterol side-chain cleavage enzyme system termed F2 (H(2)N-P450scc-adrenodoxin reductase-adrenodoxin-COOH), was stably expressed in nonsteroidogenic COS-1 cells. Multiple clones were obtained and analyzed, identifying the clone COS-F2-130 as the most active in converting 22R-hydroxycholesterol (22R-OH-C) to pregnenolone. The F2 fusion construct was properly transcribed and translated in COS-F2-130 cells, indicating that these cells did not proteolytically cleave the F2 protein. Steroid analyses show that the COS-F2-130 cells do not convert appreciable quantities of pregnenolone to other steroids. Isolated COS-F2-130 mitochondria showed enhanced steroidogenesis when incubated with biosynthetic N-62 StAR protein in vitro. The cells were easily transfectable with StAR expression vectors, showing that COS-F2-130 cells exhibited both StAR-independent and StAR-dependent activity. Transient expression of either full-length or N-62 StAR stimulated steroidogenesis to approximately 45% of the maximal steroidogenic capacity, as indicated by incubation with 22R-OH-C. Single, double, and triple transfections of individual vectors expressing P450scc, adrenodoxin reductase, and adrenodoxin demonstrated that the P450 moiety of the F2 fusion protein could only receive electrons from the covalently linked adrenodoxin moiety, but that free adrenodoxin reductase could foster activity of the fusion enzyme. COS-F2-130 cells provide a useful system for studying steroidogenesis, as these are the only cells described to date that convert cholesterol to pregnenolone but lack downstream enzymes that catalyze other steroidogenic reactions.

Parental concerns for the child with febrile convulsion: long-term effects of educational interventions

OBJECTIVE

To evaluate long-term effects of educational interventions on parental concerns for children with febrile convulsions (FC).

SUBJECTS AND METHODS

209 FC parents were recruited from southern Taiwan, and assigned into program or pamphlet groups by their choices. A questionnaire was used to examine the parental concerns at 4 time points: prior to the interventions, 3 months, 1 year, and 2 years after the interventions.

RESULTS

The concern scores were high before the interventions. Parents concerned that their child is apt to get a fever, has further seizures in the night, that FC results in potential brain damage and is life threatening. After interventions the concern scores were significantly lower for the program group than for the pamphlet group. The educational program was the most significant factor that influenced the change in parental concerns. The recurrence of FC did not significantly influence the change in the concern trajectory in the program group but showed a significant difference in the pamphlet group.

CONCLUSION

FC parental concerns decreased as time passed particularly in the program group. The educational program was the significant factor that influenced the change of concern trajectories, and the recurrent/non-recurrent factor influenced the change of concern only in pamphlet group. FC parental concerns should be assessed, and information given combined with emotional support.