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BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is caused by multiple factors including hepatic oxidative stress, lipotoxicity, and mitochondrial dysfunction. Obesity is among the risk factors for NAFLD alongside type 2 diabetes mellitus and hyperlipidemia. α- mangostin (α-MG) extracts from the pericarps of mangosteen (Garcinia mangostana Linn.) may regulate high fat diet-induced hepatic steatosis; however the underlying mechanisms remain unknown. The aim of this study was to investigate the regulatory effect of α-MG on high fat diet-induced hepatic steatosis and the underlying mechanisms related to mitochondrial functionality and apoptosis in vivo and in vitro. METHODS: Sprague Dawley (SD) rats were fed on either AIM 93-M control diet, a high-fat diet (HFD), or high-fat diet supplemented with 25 mg/day mangosteen pericarp extract (MGE) for 11 weeks. Thereafter, the following were determined: body weight change, plasma free fatty acids, liver triglyceride content, antioxidant enzymes (superoxide dismutase, SOD; glutathione, GSH; glutathione peroxidase, GPx; glutathione reductase GRd; catalase, CAT) and mitochondrial complex enzyme activities. In the in vitro study, primary liver cells were treated with 1 mM free fatty acid (FFA) (palmitate: oleate acid = 2:0.25) to induce steatosis. Thereafter, the effects of α-MG (10 µM, 20 µM, 30 µM) on total and mitochondria ROS (tROS, mitoROS), mitochondria bioenergetic functions, and mitochondrial pathway of apoptosis were examined in the FFA-treated primary liver cells. RESULTS: The MGE group showed significantly decreased plasma free fatty acids and hepatic triglycerides (TG) and thiorbarbituric acid reactive substances (TBARS) levels; increased activities of antioxidant enzymes (SOD, GSH, GPx, GRd, CAT); and enhanced NADH-cytochrome c reductase (NCCR) and succinate-cytochrome c reductase (SCCR) activities in the liver tissue compared with HFD group. In the in vitro study, α-MG significantly increased mitochondrial membrane potential, enhanced cellular oxygen consumption rate (OCR), decreased tROS (total ROS) and mitoROS (mitochondrial ROS) levels ; reduced Ca2+ and cytochrome c (cyt c) release from mitochondria, and reduced caspases 9 and 3 activities compared with control group. CONCLUSION: These findings demonstrate α-MG attenuated hepatic steatosis in high fat-diet fed rats potentially through enhanced cellular antioxidant capacity and improved mitochondrial functions as well as suppressed apoptosis of hepatocytes. The findings of study represent a novel nutritional approach on the use of α-MG in the prevention and management of NAFLD.

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The long-term species diversity patterns in marine fish communities are garnering increasing attention from ecologists and conservation biologists. However, current databases on quantitative abundance information lack consistent long-term time series, which are particularly important in exploring the possible underlying mechanism of community changes and evaluating the effectiveness of biodiversity conservation measures. Here we describe an impinged fish assemblage dataset containing 1, 283, 707 individuals from 439 taxa. Once a month over 19 years (1987-1990 and 2000-2014), we systematically collected the fish killed by impingement upon cooling water intake screens at two nuclear power plants on the northern coast of Taiwan. Because impingement surveys have low sampling errors and can be carried out over many years, they serve as an ideal sampling tool for monitoring how fish diversity and community structure vary over an extended period of time.

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BACKGROUND/AIMS: Hepatocellular carcinoma is commonly found in Asian countries and prognosis still remains unsatisfactory due to recurrence after surgical tumor resection. METHODOLOGY: We try to demonstrate the recurrence and survival time in 99 surgical patients grading by tumor cellular differentiation from surgical specimen. RESULTS: The rates of well, moderate, and poor differentiation were encountered in 21 cases (21.2%), 61 cases (61.6%) and 17 cases (17.7%), respectively. Small tumor (< 3 cm) was found in only one (5.9%) in the poor differentiation group and 38.1% and 37.7% in the well and moderate differentiation groups. Capsular invasion was found in 13 (61.9%), 39 (63.9%) and 7 (41.1%) in the well, moderate and poor differentiation group, respectively. We found 41.9% (18/43) and 22.4% (13/58) to be tumor free in capsule invasion (-) and (+) after a period of 18.1 and 29.9 months, respectively. However, the recurrent time was 10.6 and 11.3 months, respectively with no significant difference (p > 0.05). Vascular invasion was more frequent in the poor differentiation group (76.5%) than the well (23.8%) and moderate (60.7%) differentiation groups (P < 0.05). We found 23.5% (4/17) and 35% (21/60) to be tumor free but the recurrence time was 6.5 and 14.1 months for the vascular invasion (-) and (+), respectively. The residual median survival times were 6.5 and 14 months after recurrence, respectively. The tumor recurrence rates were 52.7% (11/21), 52.4% (32/61), and 35.5% (6/17) and recurrence times were 11.7, 11.9, and 4.5 months for the well, moderate and poor differentiation group respectively totally. The recurrence time of young age group (< 39 years old) was shorter than the others and there was no patient of well differentiation less than 40 years old. The recurrence time was shorter in the poor differentiation group but there was no significant difference according to age group. The median survival times were 22.2, 22.9, and 9.5 months for each group, respectively. CONCLUSIONS: Differentiation of hepatocellular carcinoma cell had a clinical significance and was found to be positively correlated with the invasive proclivity. The median survival time was longer in both the well and moderate differentiation group, but not in the poor differentiation group. The clinical data revealed that the extended operations performed upon the patients with poor differentiation effected the recurrence time but not the survival time.

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OBJECTIVE: To identify 18 steps to 3-component attitude scale construction. METHODS: Examples are provided to illustrate each step. RESULTS: The presentation primarily focused on specific steps in constructing meaningful health attitude scales. Further, the importance and concept of various forms of realibilty and validity are provided. Special attention is given to factors affectiving psychometric evidence. CONCLUSIONS: In order to meaningfully measure health related attitudes, researchers and evaluators should consider following the steps outline in the presentation.

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HIV/AIDS has intruded upon the geographic, political, ethnic, gender, and sexual orientation of communities all over the world. As of April 1999, Russia has recorded approximately 13,532 cases of HIV infection. Since the costs of treatment are expensive for many countries, and especially for Russia, educational intervention appears to offer the most effective and affordable solution. A quasi-experimental design, with pre/post tests and intervention (through video education)/control groups, was used to study 20 public schools in St. Petersburg, Russia. Results confirmed the lack of HIV/AIDS education in schools and insufficient information sources from parents, friends, and public health education. ANCOVA statistics demonstrated that use of video education significantly improved students' scores on knowledge and attitudes related to HIV/AIDS prevention. Thus, health educators should consider video education as an effective and efficient tool to present facts to a young audience when they face constraints of shortage of funds, lack of trained teachers, and scarcity of related information.

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Two forms of rat brain cytosolic diacylglycerol kinase (EC2.7.1.107) were separated by heparin-agarose column chromatography. These forms, designated DGK-I and DGK-II, were not interconvertible as determined by rechromatography. DGK-I and DGK-II had respective molecular masses of 88 and 180 kDa, as measured by Sepharose 6B chromatography. Both forms preferred diacylglycerol over monoacylglycerol and were insensitive to R59022. DGK-II, but not DGK-I, was activated by an activator substance prepared from chicken egg yolk. DGK-II was activated by a rat brain cytosolic activator and was exclusively sensitive to 5'-AMP-mediated inactivation. Further studies revealed that these two forms had the following distinct characteristics: (a) substrate specificity, (b) inhibition by heparin, (c) sensitivity to lysine-containing polyamino acids, and (d) responses to different phospholipids. In general, DGK-II was more responsive to various inhibitors and activators, making it a prime candidate for a regulatable enzyme.

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Cytosolic diacylglycerol kinase was irreversibly inactivated by 5'-AMP since the enzyme remained less active after the removal of 5'-AMP by P-10 gel chromatography. The inactivation was time-dependent, suggesting the involvement of a covalent bond modification. A reconstitution experiment detected a rat brain cytosolic mediator for the effect of 5'-AMP. A protein kinase rich fraction prepared from rat liver was also capable of restoring the sensitivity of diacylglycerol kinase-II to 5'-AMP. We propose that 5'-AMP-activated protein kinase is the mediator which inactivates diacylglycerol kinase-II, possibly by phosphorylation.

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Cytosolic diacylglycerol kinase was inhibited drastically by nucleoside monophosphate. The inhibition was relatively specific for adenosine-5'-monophosphate (5'-AMP), although uridine-5'-monophosphate was also effective. The effect of 5'-AMP on diacylglycerol kinase appeared to be indirect since the degree of inhibition lessened with the dilution of the cytosol and the more purified enzyme failed to respond to 5'-AMP. A 5'-AMP-dependent mediator is proposed to be involved in the inactivation of diacylglycerol kinase.

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Cupric ion (Cu2+), in complex form, functions as a selective oxidizing agent for a variety of compounds in the qualitative Benedict test. Cupric ion is reduced to cuprous ion (Cu+) in the reaction. We found that the cuprous ion formed in this type of redox reaction could be detected and quantified using 2,2'-bicinchoninic acid. This reagent produced an intense purple complex with cuprous ion. The color development in this modified Benedict test was dependent on pH, temperature, and time. The reaction is insensitive to ethanol and sodium dodecyl sulfate. This improved method of the Benedict test has enhanced sensitivity and makes the quantitation of compounds possible. This method should be useful for studies of Benedict-positive compounds which are available only in small amounts.

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We investigated whether or not synthetic polymers of amino acids affected the activity of rat diacylglycerol kinase. Among all the polypeptides of amino acids tested, only the polymers containing significant amounts of basic amino acid residues inhibited diacylglycerol kinase activity. Poly-L-lysine was a better inhibitor than poly-L-arginine. Both the density of positive charge and the nature of spacing amino acids of the inhibitory peptides were determining factors in interacting with the enzyme. Various polyamines were ineffective. Our observation indicated that the activity of diacylglycerol kinase might be controlled by a site which binds to a polycation.

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During the initial steps of the subcellular fractionation of rat brain homogenate, we recovered more than 100% of diacylglycerol kinase activity. The unusually high yields prompted us to examine the possibility that we had removed an endogenous inhibitor from diacylglycerol kinase during those steps. Our study revealed the existence of a potent inhibitor of diacylglycerol kinase in the crude synaptosomal-mitochondrial fraction (P2 pellet). The inhibitory substance was water soluble upon organic solvent extraction. The inhibitory activity of the substance was retained after extensive dialysis, suggesting the macromolecular nature of this compound. This substance may represent an important physiological regulator of diacylglycerol kinase.

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The displacement characteristics of [3H]5-hydroxytryptamine (5-HT1) binding by several serotonergic ligands were studied in the chick embryo brain. Although most of ligands tested displaced [3H]5-HT in a manner suggestive of a single site, displacement curves for (+/-)-8-hydroxy-dipropylaminotetralin (8-OH-DPAT), 5-methoxytryptamine, 5-methyltryptamine and 5-methoxy-N,N-dimethyltryptamine displayed non-unity Hill plots, suggesting multiple site interactions. However, if spiperone (2 microM) was included in the assays, the Hill coefficients of these compounds were all similarly increased toward unity, suggesting that 8-OH-DPAT as well as 5-methoxy and 5-methyl substituted tryptamines, have a high affinity for and can discriminate 5-HT1A binding sites in the chick embryo brain.

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We have investigated the effects of substituting lipoprotein depleted serum (LPDS) for normal fetal calf serum (FCS) in culture media on cholesterol ester concentrations and the activity of the ester hydrolases in cultured glioblastoma (C-6 glial) cells. Glial cells grown in media supplemented with 10% FCS contained 16-23% of total cholesterol as esterified sterol. Total sterol content of the cells cultured in media supplemented with LPDS was reduced by 55-75% as compared to cells cultured in FCS media and none of this sterol was in esterified form. Cholesterol ester hydrolase activity was maximal at pH values of 4.5 and 6.5 and required Triton X-100 for optimal activity. Cholesterol ester hydrolase activity at pH 4.5 was significantly higher in cells grown in FCS media than in cells cultured in LPDS media, but the activity at pH 6.5 was not significantly different. The protein: DNA ratio of cells cultured in FCS was higher than in cells cultured in LPDS. These findings indicate that the increase in cholesterol ester concentrations in cells is accompanied by increased activity of lysosomal cholesterol ester hydrolase; and suggest that, in cells cultured in FCS, the availability of free cholesterol for incorporation into cellular membranes is regulated by cholesterol ester hydrolase. The findings also indicate that changes in growth and differentiation of cells cultured in LPDS may be related to reduced availability of exogenous cholesterol.

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Three monoamine oxidase (MAO) inhibitors--pargyline, clorgyline and deprenyl--as well as the serotonin (5-HT, 5-hydroxytryptamine) releasing agent fenfluramine were administered to developing chick embryos and the effects on [3H]5-HT binding parameters and endogenous 5-HT levels were assessed. Multiple, but not acute, pretreatments with any of the three MAO inhibitors significantly increased 5-HT levels (p less than 0.01) and decreased receptor number (Bmax) to a maximum of 20% (p less than 0.01) without affecting the affinity (KD). When d,l-5-hydroxytryptophan (d,l-5-HTP) was similarly administered there were large increases in 5-HT levels (p less than 0.01), but no significant effects on either Bmax or KD. However, if d,l-5-HTP was co-administered with any of the MAO inhibitors there was a significant (p less than 0.01) enhancement of the MAO inhibitor-induced down-regulation to a maximum of about 40%. Multiple pretreatments with fenfluramine resulted in dose-related decreases in 5-HT levels (p less than 0.01) and Bmax (p less than 0.01) without affecting KD. The largest decrease in [3H]5-HT binding sites inducible by fenfluramine treatment alone was also about 40%. When given in combination with d,l-5-HTP, there was a potentiation of the down-regulation capabilities of fenfluramine at several different dosage levels; however, maximal down-regulation was also limited to 40%. Evidence was presented suggesting that these effects were not due to endogenous 5-HT or drugs remaining in the tissue preparation. The overall evidence implies that merely increasing endogenous 5-HT levels, as by precursor administration, does not necessarily induce down-regulation unless the 5-HT is also made available as functional 5-HT.

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The hypocholesterolemic agent 3 beta-(2-diethylaminoethoxy)androst-5-en-17-one . HCl (U18666A) is known to induce experimental epilepsy. The possibility that this drug interferes with cholesteryl ester formation in glioblastoma cells was examined. The incorporation of radioactive oleic acid into cellular cholesteryl ester was drastically and specifically inhibited by U18666A. The inhibitory effect of U18666A persisted in different oleic acid concentrations. Kinetic studies revealed the rapidity of U18666A action. U18666A was found to be ineffective in inhibiting acyl-CoA:cholesterol acyltransferase activity when it was added directly to the cell homogenates. In contrast, the acyltransferase activity was greatly diminished in homogenates derived from U18666A-treated cells. Thus, U18666A appeared to block cellular cholesteryl ester biosynthesis by indirectly inactivating acyl-CoA:cholesterol acyltransferase activity in a cell-dependent manner. The potent inhibition of cholesteryl ester formation by U18666A represents one unique aspect of the drug which might contribute to its ability to induce chronic epileptiform activity.

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The perturbation of cellular cholesteryl ester biosynthesis in glioblastoma C-6 cells by lidocaine was investigated. Lidocaine specifically inhibited the incorporation of radioactive oleic acid into cellular cholesteryl ester but had no significant effect on the incorporation of oleic acid into phosphatidylcholine. Oxygenated cholesterol-enhanced cholesteryl ester formation was less sensitive to lidocaine inhibition. Several other local anesthetics were compared. Lidocaine altered cholesteryl ester formation in time- and dose-dependent manners. Lidocaine was a powerful inhibitor initially and its potency declined with time. Lidocaine was capable of directly inhibiting acyl-CoA:cholesterol acyltransferase (ACAT) activity in broken cell homogenates. The lidocaine-mediated inhibition of cellular cholesteryl ester formation triggered an enhanced intracellular ACAT activity that was not fully expressed in the presence of lidocaine. The activation of ACAT activity by lidocaine might represent a compensatory mechanism by which the inhibitory effect of lidocaine was partially overcome with time.

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Saturable and specific binding sites for 5-[3H]hydroxytryptamine (5-HT, serotonin) characterized by a KD of 3.5-4.5 nM were detected in the chick embryo brain and were shown to develop linearly as a function of age, weight, and protein content. Saturation and displacement studies using unlabeled 5-HT as the displacing ligand suggested a single population of binding sites. However, displacement studies using 5-methoxytryptamine, lysergic acid diethylamide (LSD), 2-bromo-lysergic acid diethylamide (BOL), methysergide, and spiperone as competing ligands suggested the existence of subclasses of [3H]5-HT binding sites because the Hill coefficients were less than unity. When compared with the reported [3H]5-HT binding sites (5-HT1) in the rat forebrain, the IC50 values of the competing ligands were similar. However, the Hill coefficients for LSD and methysergide were less than unity which suggested that the [3H]5-HT binding sites in the chick embryo brain may be more similar to those found in rat spinal cord than rat forebrain. To study [3H]5-HT binding site regulation and development, various serotonergic compounds were injected into the chorioallantoic fluid of the eggs at different times during embryonic development. Multiple pretreatments with d,l-5-hydroxytryptophan, 5-HT, or BOL were found to have no significant effects on either the affinity (KD) or number (Bmax) of specific [3H]5-HT binding sites. Multiple pretreatments with p-chlorophenylalanine were found to increase the Bmax of specific [3H]5-HT binding by 23% (p less than 0.01) whereas multiple pretreatments with LSD were found to decrease the Bmax of specific binding by 45% (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

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Butyrate induced marked morphological changes in cultured human retinal pigment epithelial (RPE) cells. The cells assumed a flattened structure within six hours of exposure to butyrate. The butyrate-treated retinal pigment epithelial cells possessed an enhanced capacity to esterify retinol. Among all short chain organic acids tested, butyrate was by far the most effective, followed by pentanoate and hexanoate. The inductive effect of butyrate was specific for retinol esterification, since the incorporations of fatty acid into phosphatidyl choline and cholesteryl ester were not enhanced. Time-dependent, butyrate-enhanced retinol esterification may be related to the inhibition of cell proliferation. This represents the first report on the induction of retinol esterification in cultured retinal pigment epithelial cells.

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To investigate the perturbation of ubiquinone biosynthesis by a hypocholesterolemic drug, 3 beta-(2-diethylaminoethoxy)androst-5-en-17-one hydrochloride (U18666A), we measured the incorporation of radioactive mevalonate, methionine, tyrosine, and 4-hydroxybenzoic acid into ubiquinone in glioblastoma cells. These four precursors unanimously showed that ubiquinone biosynthesis was not significantly altered by U18666A, which blocked cholesterol biosynthesis at steps beyond mevalonate formation. The fluctuation of the endogenous mevalonate level had little effect on ubiquinone biosynthesis, implying the relative stability of cellular ubiquinone biosynthesis. Furthermore, exogenously added mevalonate did not have an appreciable effect on ubiquinone biosynthesis. The major ubiquinone produced in rat glioblastoma cells was identified as ubiquinone-9. The mevalonate-derived products accumulated in the U18666A-treated cells differed significantly from those reported in a broken cell study, suggesting the existence of delicate mechanisms regulating the formation of cholesterol intermediates.

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Caffeine, a well-known behavior stimulant, was found to activate the fatty acid release mechanism in glioblastoma cells. The enhancement of the liberation of fatty acids from esterified complex lipids by caffeine was time dependent. Cell density had a strong influence on the responsiveness to caffeine. The mobilization of unsaturated fatty acids were preferentially stimulated by caffeine. Therefore, caffeine may alter membrane structure and enhance eicosanoid biosynthesis.

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