Deficit of state-dependent risk attitude modulation in gambling disorder.

Gambling disorder (GD) is often considered as a problem of trait-like risk preference. However, the symptoms of GD cannot be fully understood by this trait view. In the present study, we hypothesized that GD patients also had problem with a flexible control of risk attitude (state-dependent strategy optimization), and aimed to investigate the mechanisms underlying abnormal risk-taking of GD. To address this issue, we tested GD patients without comorbidity (GD group: n=21) and age-matched healthy control participants (HC group: n=29) in a multi-step gambling task, in which participants needed to clear 'block quota' (required units to clear a block, 1000-7000 units) in 20 choices, and conducted a task-functional magnetic resonance imaging (fMRI) experiment. Behavioral analysis indeed revealed a less flexible risk-attitude change in the GD group; the GD group failed to avoid risky choice in a specific quota range (low-quota condition), in which risky strategy was not optimal to solve the quota. Accordingly, fMRI analysis highlighted diminished functioning of the dorsolateral prefrontal cortex (dlPFC), which has been heavily implicated in cognitive flexibility. To our knowledge, the present study provided the first empirical evidence of a deficit of state-dependent strategy optimization in GD. Focusing on flexible control of risk attitude under quota may contribute to a better understanding of the psychopathology of GDs.

Effects of gassericins A and T, bacteriocins produced by Lactobacillus gasseri, with glycine on custard cream preservation.

Lactobacillus gasseri LA39 and LA158 isolated from human-infant feces produce bacteriocins named gassericins A and T, respectively. Both gassericins have high heat stability (121 degrees C, 10 min), good pH tolerance (pH 2-11), and strong bactericidality against many gram-positive bacteria, especially lactic acid bacteria, and thus are expected to be effective food preservatives. A microwell plate assay against 12 strains of custard cream spoilage bacteria showed that the gassericins had broader antibacterial spectra than nisin A. Although the gassericins allowed gram-negative isolates to grow, they successfully inhibited the growth of all tested bacterial strains in microwells with the addition of glycine. Glycine was bacteriostatic against many strains except lactic acid bacteria. For practical use, gassericin A was efficiently produced by cultivation in a food-grade medium improved using cheese whey, nourishing proteose peptone, and surfactant yolk lecithin. The practical preservative effect of gassericin A and glycine was verified from the viability of 4 isolated strains, Bacillus cereus, Lactococcus lactis ssp. lactis, Achromobacter denitrificans, and Pseudomonas fluorescens, in custard creams. Custard cream containing 123 arbitrary units of gassericin A per milliliter entirely growth-inhibited the 2 gram-positive strains. In custard cream containing an insufficient amount of gassericin A (49 arbitrary units/mL), the gram-positive strains gradually grew but were completely inhibited by the addition of 0.5% (wt/wt) glycine. The 2 gram-negative strains did not multiply even in the additive-free custard cream, probably because of the unsuitable growth environment. This is the first report showing the combined effect of bacteriocin and glycine and their application for food preservation, which may be helpful for future use in the food industry.

Microbial community analysis of food-spoilage bacteria in commercial custard creams using culture-dependent and independent methods.

Custard cream is made from highly nutritive raw materials such as milk and sugar and is easily spoiled by the multiplication of specific microbial contaminants or residents. However, this spoilage microbial community has not been studied. We determined the spoilage microbiota in commercial custard creams using culture-dependent and independent methods. Using the culture-dependent analysis with various agar media, 185 bacterial colonies and 43 eukaryal colonies were isolated from 7 commercial custard cream products. All bacterial isolates were morphologically, physiologically, and genetically identified as bacilli, staphylococci, lactic acid bacteria, and psychrotrophic gram-negative rods. Using culture-independent molecular analysis, the PCR-denaturing gradient gel electrophoresis technique, spoilage of the commercial custard creams was found to be caused by bacilli, staphylococci, lactic acid bacteria, psychrotrophic gram-negative rods, Anoxybacillus sp., Caurobacter sp., and Streptococcus sp. bacteria. The detected spoilage bacteria were the same species as previously detected in spoiled milk products and shown in other reports, suggesting that spoilage bacteria in a raw material easily grow in processed foods made from milk. We determined the spoilage microbial communities in commercial custard creams, and these are the first data concerning spoilage microbiota in nonfermented processed foods using a culture-independent analysis. Our study will be useful for the manufacture and safe preservation of dairy products because the first step toward safe food preservation by food manufacturers is to understand the spoilage microbiota in a target food to select optimal preservatives and to reduce the use of food additives.

Prevention of second primary tumors by an acyclic retinoid, polyprenoic acid, in patients with hepatocellular carcinoma. Hepatoma Prevention Study Group.

BACKGROUND: In patients with hepatocellular carcinoma (hepatoma), the rate of recurrent and second primary hepatomas is high despite surgical resection and percutaneous ethanol-injection therapy. We developed an acyclic retinoid, polyprenoic acid, that inhibits hepatocarcinogenesis in the laboratory and induces differentiation and apoptosis in cell lines derived from human hepatoma. In a randomized, controlled study, we tested whether the compound reduced the incidence of recurrent and second primary hepatomas after curative treatment. METHODS: We prospectively studied 89 patients who were free of disease after surgical resection of a primary hepatoma or the percutaneous injection of ethanol. We randomly assigned the patients to receive either polyprenoic acid (600 mg daily) or placebo for 12 months. We studied the remnant liver by ultrasonography every three months after randomization. The primary end point of the study was the appearance of a histologically confirmed recurrent or new hepatoma. RESULTS: Treatment with polyprenoic acid significantly reduced the incidence of recurrent or new hepatomas. After a median follow-up of 38 months, 12 patients in the polyprenoic acid group (27 percent) had recurrent or new hepatomas as compared with 22 patients in the placebo group (49 percent, P = 0.04). The most striking difference was in the groups that had second primary hepatomas--7 in the group receiving polyprenoic acid as compared with 20 in the placebo group (P = 0.04 by the log-rank test). Cox proportional-hazards analysis demonstrated that as an independent factor, polyprenoic acid reduced the occurrence of second primary hepatomas (adjusted relative risk, 0.31; 95 percent confidence interval, 0.12 to 0.78). CONCLUSIONS: Oral polyprenoic acid prevents second primary hepatomas after surgical resection of the original tumor or the percutaneous injection of ethanol.

Ibudilast, an anti-allergic and cerebral vasodilator, modulates superoxide production in human neutrophils.

We evaluated the effect of ibudilast on superoxide generation in human neutrophils by chemiluminescence development using luciferine analog, FCLA. By incubating neutrophils with ibudilast (2-200 microM) for more than 10 minutes, fMLP- or PMA-induced chemiluminescence was enhanced. However, the fMLP-induced chemiluminescence was suppressed by incubation for less than 10 minutes. This suppressed effect was missing with PMA-induced chemiluminescence. On the both fMLP- and PMA-induced chemiluminescence, the priming effect of ibudilast was further enhanced by the treatment with H-7, a protein kinase C inhibitor. In contrast, the priming effect of ibudilast on the fMLP-induced chemiluminescence was abolished by the treatment with ST-638, a selective inhibitor of tyrosine kinase. Ibudilast showed a transient stimulatory effect on cyclic AMP accumulation which continued for only a few minutes. Ibudilast showed no significant effect on phospholipase D dependent chemiluminescence, 1,4,5 trisphosphate level, or protein kinase C activity. Ibudilast inhibited extracellular calcium influx. These results suggest that ibudilast acts on or through tyrosine kinase to achieved its priming effect on the fMLP-induced chemiluminescence. The early and transient increase in cyclic AMP level may explain the inhibitory effect of ibudilast on the fMLP-induced chemiluminescence after short time of incubation.

Heterogeneity of circulating and exudated polymorphonuclear leukocytes in superoxide-generating response to cyclic AMP and cyclic AMP-elevating agents. Investigation of the underlying mechanism.

It has been found that cyclic AMP and cyclic AMP-elevating agents inhibit formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated superoxide production from polymorphonuclear leukocytes (PMNs). The quantitative differences of this inhibitory effect on human and rabbit blood versus human salivary and rabbit peritoneal (tissue) PMNs were investigated. PMNs from all sources showed the same pattern of fMLP-stimulated superoxide generation, although it was slightly higher in tissue PMNs. However, treatment with salbutamol differentially blunted fMLP-stimulated superoxide production from blood PMNs compared with tissue PMNs in both human and rabbit. While it could inhibit production from blood PMNs by 30-60%, it had only a negligible effect on generation from tissue PMNs. Similarly, forskolin, phosphodiesterase IV inhibitor Ro-201724, and dibutryl cyclic AMP showed significantly higher inhibitory effects on superoxide generation from blood PMNs than tissue PMNs in both species. beta-Adrenergic receptors, cyclic AMP accumulation, and protein kinase A activity were investigated in blood versus tissue PMNs to clarify the mechanism underlying the above-mentioned differences. At the beta-adrenergic receptor level, no significant changes were detected in the number or the binding affinity of the receptors in tissue versus blood PMNs of human and rabbit. On the other hand, cyclic AMP accumulation was significantly higher in response to salbutamol and Ro-201724 in fMLP-stimulated blood versus tissue PMNs in human and rabbit. At the same time, blood PMNs showed significantly higher cyclic AMP-dependent protein kinase A activity than tissue PMNs in human and rabbit. We concluded that tissue PMNs are less responsive to the effect of cyclic AMP-elevating agents in terms of fMLP-stimulated superoxide inhibition. This is due to differences, at least, at two levels. The first is lower accumulation of cyclic AMP and the second is lower protein kinase A activity in tissue versus blood PMNs.

Opioid receptor interaction and adenylyl cyclase inhibition of dihydroetorphine: direct comparison with etorphine.

To find out the reason of weak addiction property of dihydroetorphine, we compared the affinities of dihydroetorphine to the type selective opioid receptor and inhibition effect on the adenylyl cyclase activity with those of etorphine. Dihydroetorphine and etorphine have almost the same binding affinities to all types (mu, delta, and kappa) of opioid receptors and antagonist binding sites, and have similar inhibition activities to forskolin stimulated adenylyl cyclase. However, dihydroetorphine showed significantly smaller value of DTNB-index compared with that of etorphine. This differentiation may explain partly the high analgesic with low dependence properties of dihydroetorphine.

Characterization of opioid receptors in the Mongolian gerbil cerebellum.

Characteristics of opioid receptors binding in the Mongolian gerbil cerebellum were determined by in vitro radioligand binding technique. Homogenate of cerebellar membranes possessed a binding capacity for 3H-DAMGO, a mu-agonist, and for 3H-diprenorphine, an antagonist of mu, delta and kappa-receptors. These bindings were saturable, and characterized by high affinity (Kd values: 1.55 +/- 0.43 nM for 3H-DAMGO and 0.56 +/- 0.20 nM for 3H-diprenorphine) and high density (Bmax: 127.8 +/- 23.8 fmoles/mg protein for 3H-DAMGO and 135.8 +/- 9.03 fmoles/mg protein for 3H-diprenorphine). Autoradiographically, the binding sites were predominantly located in the molecular layer of the cerebellum. 3H-DPDPE, a delta-agonist, showed only very small binding capacity to the cerebellar membranes. The kappa-agonist, 3H-U-69593, also showed very small binding capacity to the cerebellar membranes except in the early postnatal period. Thus, the gerbil cerebellum can be considered as a tissue containing a homogeneous population of mu-opioid receptors.

A proposal for purification of salivary polymorphonuclear leukocytes by combination of nylon mesh filtration and density-gradient method: a validation by superoxide- and cyclic AMP-generating responses.

Isolation and purification of salivary polymorphonuclear leukocytes (SPMNs) from accompanying epithelial cells was presented by using a density-gradient method with Ficoll. SPMNs samples prepared by already established methods (nylon mesh filtration) was compared with SPMNs samples after further purification by Ficoll (d = 1.083). Microscopically, SPMNs samples after nylon mesh filtration contain higher percentage of epithelial cells than SPMNs samples after Ficoll centrifugation. In response to stimulation of superoxide generation, both samples showed the same pattern of response. However, in response to forskolin and prostaglandin E1, cyclic AMP levels in samples after nylon mesh purification were significantly higher than in samples after Ficoll purification because of the presence of contaminating epithelial cells. We can conclude that, although nylon mesh filtration is satisfactory when we need to examine superoxide generation but further purification is necessary when we want to measure factors like intracellular cyclic AMP formation.

Effects of cytosine arabinoside on rat and rabbit embryos cultured in vitro.

The technique of rabbit whole embryo culture for 48 or 24 hr from day 9, 10 or 11 of gestation has been improved for elucidation of species differences. The effects of 1-beta-d-arabinofuranosylcytosine (ara-C) and its metabolite 1-beta-d-arabinofuranosyluracil (ara-U) on cultured rat and rabbit embryos were examined. Slc:SD rats on day 10.5 of gestation were explanted and cultured in rat serum containing ara-C (5-10 mug/ml) for 48 hr. Rabbit embryos of the Japanese White strain on day 9 or day 10 of gestation were explanted and cultured in rabbit serum containing ara-C (0.03-1.0 or 3-30 mug/ml) or ara-U (1.0 or 30 mug/ml) for 48 or 24 hr. Cultured rat embryos exposed to ara-C showed abnormalities of the head (malformations of the telencephalon, mesencephalon and rhombencephalon), mandible and limb bud, and short tail. Growth parameters, such as crown-rump length, head length, protein content and somite number, were reduced with increasing concentrations of ara-C. In the rabbit, embryos cultured from day 9 of gestation for 48 hr showed abnormalities of the head (telencephalon, rhombencephalon), mandible and limb bud with ara-C at 0.1 mug/ml and higher concentrations. Concentration-dependent decreases in crown-rump length, head length and protein content were observed. The findings in embryos cultured from day 10 of gestation were similar to those in embryos cultured from day 9. Ara-U produced no detectable abnormalities in embryos cultured for 48 hr from day 9 of gestation, or for 24 hr from day 10. These results indicate that ara-C has teratogenicity in vitro that is similar in both rat and rabbit embryos.

[Pharmacological studies on human urinary kallidinogenase (SK-827): cerebral protective effects].

We investigated the cerebral protective effects of human urinary kallidinogenase (SK-827) in rabbits. The following results were obtained: 1) At a dose of 5.0 x 10(-3) to 1.25 x 10(-2) PNA U/kg, SK-827 significantly inhibited the decrease of focal cerebral blood flow and the impairment of electrocorticogram (ECoG) activity in infarcted rabbits. 2) SK-827 at a dose of 2.5 x 10(-3) PNA U/kg inhibited the development of infarction area induced by internal carotid arterial injection of glass beads. 3) SK-827 at a dose of 2.5 x 10(-3) to 5.0 x 10(-3) PNA U/kg inhibited the decrease of cerebral cortical pO2 induced by 5% oxygen inhalation. 4) On subacute phase 7 days after the destruction of internal capsule, SK-827 at a dose of 1.25 x 10(-2) PNA U/kg improved the abnormality of spontaneous ECoG. These findings suggest that SK-827 minimizes the reduction of cerebral function induced by ischemia.

[Pharmacological studies on human urinary kallidinogenase (SK-827): effects on cerebral metabolism].

We investigated the effects of human urinary kallidinogenase (SK-827) on cerebral metabolism in normal and infarcted rabbits. SK-827 did not influence cerebral glucose and oxygen uptake in normal rabbits. In infarcted rabbits, cerebral glucose and oxygen uptake significantly decreased. SK-827 tended to inhibit the decrease of cerebral blood flow, and significantly inhibited the decrease of cerebral glucose and oxygen uptake in infarcted rabbits. Thus, SK-827 improved cerebral glucose metabolism in infarcted rabbits.

Pharmacological studies on cutaneous inflammation induced by ultraviolet irradiation (1): quantification of erythema by reflectance colorimetry and correlation with cutaneous blood flow.

This study was conducted to quantify the intensity of ultraviolet (UV) erythema in guinea pigs, a method for evaluating anti-inflammatory drugs, and to clarify any correlation of erythema with cutaneous blood flow. Skin color and cutaneous blood flow in non-administered and indomethacin-administered animals were measured by a colorimeter and a laser Doppler flowmeter over time after UV-irradiation treatment. Skin color was indicated by a XYZ colorimetric system and L*a*b* color space. In either colorimetric system, the values of two indices, x and y or a* and b*, increased along with the intensification of erythema. The increase in the chroma (C*) value calculated from a* and b* was UV-dose-dependent. This value was significantly suppressed by indomethacin 0.5-4 hr after irradiation, and it was found to be a clear and sensitive index for evaluating the suppressive effect of drugs. Cutaneous blood flow also increased with UV irradiation. Indomethacin significantly suppressed this increase 2-3 hr after UV irradiation. The changes of cutaneous blood flow correlated with those of C*. These results suggested C* was a suitable parameter to quantify UV erythema, and the change of skin color in UV erythema reflected the change of cutaneous blood flow.

Hypothermic prevention of the hippocampal damage following ischemia in Mongolian gerbils comparison between intraischemic and brief postischemic hypothermia.

The protective effect on ischemic hippocampal damage was compared between intra- and postischemic hypothermia in Mongolian gerbils and its regional preference was evaluated. Male Mongolian gerbils were subjected to transient forebrain ischemia and the hippocampus 7 days after ischemia was examined histologically. In the intraischemic hypothermia (29-31 degrees C) group, CA1 damage was completely prevented in spite of spontaneous postischemic hyperthermia. In contrast, the same degree of brief postischemic hypothermia exerted no preventive effect. While neurons in the subiculum and CA2 sector were also protected against ischemic damage by intraischemic hypothermia, injured pyramidal neurons were always seen in the CA4 sector.

Glucagon modulates superoxide generation in human polymorphonuclear leucocytes.

It has been found that leucocytes possess receptor sites for glucagon and glucagon was shown to increase during bacterial infection. To verify the interconnection between glucagon, leucocytes and bacterial infection we studied the effect of glucagon on superoxide generation and second messenger transduction in PMNs. We found that glucagon could not stimulate chemiluminescence by itself but it could enhance FMLP- but not PMA-induced chemiluminescence in a concentration (50-800 pg/ml) dependent manner. However, after incubation of PMNs with 10 microM of ST-638 (a tyrosine kinase inhibitor) the enhancement effect converted into inhibitory effect. We also found that glucagon treatment of PMNs increased both IP3 and cyclic AMP levels as second messengers. ST-638 greatly attenuated the IP3 increment in the glucagon-treated FMLP-stimulated PMNs. From these results we can conclude that glucagon could enhance superoxide generation from FMLP-stimulated PMNs by elevating IP3. Inhibition of IP3 increment by tyrosine kinase blockade uncover the inhibitory effect of the increasing cyclic AMP on superoxide production.

Effects of trypan blue on rat and rabbit embryos cultured in vitro.

Mouse and rat whole embryo cultures are widely used in teratogenicity studies. We attempted to improve the technique of culturing rabbit embryo. Rabbit embryos of the Japanese White strain were explanted on day 9, 10 or 11 of gestation and cultured for 24 or 48 hr. Rabbit embryos on day 9 of gestation were cultured in 100% rabbit serum with a gas mixture containing 20% O(2) for the first 24 hr and 95% O(2) for the following 24 hr. Rabbit embryos on day 10 or 11 of gestation were cultured in 100, 80 or 60% rabbit serum with a gas mixture of 95% O(2) for 48 or 24 hr. The development of embryos cultured for 48 hr from day 9 or day 10 or for 24 hr from day 11 was nearly the same as that of embryos that had developed in vivo. These results indicate that rabbit embryo culture is a useful and promising technique in teratogenicity studies. We then examined the effects of trypan blue on cultured rat and rabbit embryos. Slc:SD rat embryos on day 9.5 of gestation were explanted and cultured in rat serum exposed to trypan blue (300-2700 mug/ml) for 48 hr. Rabbit embryos on day 9 or 10 of gestation were explanted and cultured in rabbit serum containing trypan blue (300-2700 mug/ml) for 48 or 24 hr. Cultured rat embryos exposed to trypan blue showed neural tube abnormalities, and all growth parameters were suppressed with increasing concentrations of trypan blue. However, trypan blue had no effect on cultured rabbit embryos. These results indicate that trypan blue has species-specific effects on embryos.

[Affinity of Z-105 to the 1,4-dihydropyridine type calcium channel and several other receptor bindings in the central nervous system].

The affinity of a 1,4-dihydropyridine (DHP) type calcium channel blocker, NZ-105 ((+/-)-2-[benzyl (phenyl) amino] ethyl 1,4-dihydro-2, 6-dimethyl-5- (5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan- 2-yl)-4-(3-nitrophenyl)-3-pyridinecarboxylate hydrochloride ethanol), on the DHP-binding site in the central nervous system and various receptor sites were compared with nicardipine and diltiazem by the use of a receptor binding assay technique. NZ-105 exhibited a displacement effect against [3H]nimodipine in the rat brain DHP-binding site with a potency similar to that of nicardipine. Nicardipine also inhibited the specific binding of several other [3H]-labelled ligands to their receptor such as adrenergic alpha 1, alpha 2, beta, dopamine D1, D2, opioid mu, delta, and kappa-type receptors. Diltiazem also showed a similar inhibitory property. However, NZ-105 showed only weak inhibition against the binding to these receptors. These results suggest that Z-105 has strong affinity to the DHP-binding site in voltage-dependent calcium channels with higher specificity.

Effect of opioids on delayed neuronal death in the gerbil hippocampus.

The effect of opioids on delayed neuronal death was evaluated in the gerbil hippocampus. Male Mongolian gerbils were subjected to transient forebrain ischemia and neuronal density was evaluated in the hippocampus 7 days following ischemia. When hypothermia during and after ischemia was prevented, treatment with morphine, U-50488H, or naloxone provided no significant protection. In contrast, a spontaneous drop in rectal temperature to 32 degrees C at the end of ischemia produced near-complete protection of CA1 pyramidal neurons. No opioids modulate the protective effect of hypothermia.

Dopaminergic unique affinity of tetrahydroberberine and l-tetrahydroberberine-d-camphor sulfonate.

l-Tetrahydroberberine-d-camphor sulfonate (THB-CS) possessed an inhibitory effect on apomorphine-induced chewing movement in a similar manner to that of tetrahydroberberine (THB). Both compounds enhanced barbiturate-induced hypnosis. They did not have an anticonvulsant effect on convulsive seizures induced by bicuculline, pentetrazole or strychnine. THB and THB-CS blocked dopamine-stimulated adenylate cyclase activity. These compounds showed almost equipotent affinities to dopamine D1 (3H-SCH-23390) and D2 (3H-spiperone) receptors but did not have significant affinity to mu-opioid, muscarinic and alpha 2-adrenergic receptors, and benzodiazepine binding sites. Furthermore, both compounds did not elicit cataleptogenic behavior, even at very high doses. These data suggest that THB and THB-CS have a central depressant effect through both D1 and D2 dopaminergic receptors and may have different modes of action from that of standard neuroleptics.