A dynamic transfer model for the estimation of 14C radioactivity in Japanese radish (Daikon) plants

A dynamic compartment model was developed to describe C accumulation in the Japanese radish plant, which is an important crop in the area around Japan's first commercial nuclear fuel reprocessing plant in Rokkasho, Aomori, Japan. Photosynthetically fixed carbon is distributed into the leaf and the root compartments, and a part of the carbon accumulated in the leaf compartment is redistributed to the root compartment. The model parameters were estimated by using data obtained from exposure of the plant to CO2. The model estimates were in good agreement with the experimental observations, showing that the newly developed compartment model is applicable to assessment of the accumulation of C in Japanese radish plants around the nuclear facility. In this study, respiration rate was set to be proportional to the carbon mass of the compartment, though the respiration rate has been assumed generally to be proportional to the growth rate of the compartment. While the estimates using both respiration rates differed only slightly from each other, the ratio of the respiratory rate of the root to that of the leaf was too high in the case of the respiratory rate proportional to the growth rate.

Development of a dynamic transfer model of (14)C from the atmosphere to rice plants

A dynamic compartment model was investigated to describe (14)C accumulation in rice plants exposed to atmospheric (14)C with temporally changing concentrations. In the model, rice plants were regarded to consist of three compartments: the ear and the mobile and immobile carbon pools of the shoot. Photosynthetically fixed carbon moves into the ear and the mobile carbon pool, and these two compartments release a part of this carbon into the atmosphere by respiration. Carbon accumulated in the mobile carbon pool is redistributed to the ear, while carbon transferred into the immobile carbon pool from the mobile one is accumulated there until harvest. The model was examined by cultivation experiments using the stable isotope, (13)C, in which the ratios of carbon photosynthetically fixed at nine times during plant growth to the total carbon at the time of harvest were determined. The model estimates of the ratios were in relatively good agreement with the experimental observations, which implies that the newly developed compartment model is applicable to estimate properly the radiation dose to the neighboring population due to an accidental release of (14)C from nuclear facilities.

Age-related bias in function of natural killer T cells and granulocytes after stress: reciprocal association of steroid hormones and sympathetic nerves

Stress-associated immune responses were compared between young (8 weeks of age) and old (56 weeks) mice. Since stress suppresses the conventional immune system (i.e. T and B cells) but inversely activates the primordial immune system (i.e. extrathymic T cells, NKT cells, and granulocytes), these parameters were analysed after restraint stress for 24 h. The thymus became atrophic as a function of age, and an age-related increase in the number of lymphocytes was seen in the liver. Although the number of lymphocytes in both the thymus and liver decreased as the result of stress, the magnitude was much more prominent in the thymus. To determine stress-resistant lymphocyte subsets, two-colour immunofluorescence tests were conducted in the liver and spleen. NKT cells were found to be such cells in the liver of young mice. On the other hand, an infiltration of granulocytes due to stress was more prominent in the liver of old mice than in young mice. Liver injury as a result of stress was prominent in young mice. This age-related bias in the function of NKT cells and granulocytes seemed to be associated with a difference in the responses of catecholamines (high in old mice) and corticosterone (high in young mice) after stress. Indeed, an injection of adrenaline mainly induced the infiltration of granulocytes while that of cortisol activated NKT cells. The present results suggest the existence of age-related bias in the function of NKT cells and granulocytes after stress and that such bias might be produced by different responses of sympathetic nerves and steroid hormones between young and old mice.

[Absolute configuration of the diastereoisomer of 2-amino-3-(1,2-dicarboxyethylthio) propanoic acid from Amanita pantherina]

Four stereoisomers of 2-amino-3-(1,2-dicarboxyethylthio) propanoic acid were prepared by reaction of L- and D-cysteine with fumaric acid. The absolute configuration of the diastereoisomer of 2-amino-3-(1,2-dicarboxyethylthio) propanoic acid from Amanita pantherina were assigned as (2R, 1'R) and (2R, 1'S) by analysis of the optical properties. Pharmacological tests showed that all of the four stereoisomers inhibited the depolarization of NMDA on spinal motorneurones in newborn rats, The inhibition intensity of L-A, D-A and D-B were higher than that of L-B.

5-HT2A promoter polymorphism is not associated with anorexia nervosa in Japanese patients

Genetic factors have been implicated in playing a significant role in susceptibility to anorexia nervosa (AN). Among many candidate genes for AN, an association with the A allele of the -1438G/A polymorphism in the promoter region of the 5-HT2A receptor has been reported. However, these findings are controversial and all patients studied to date have been Caucasian. This study was designed to determine whether this association is reproducible in Japanese subjects. This case-control study of a cohort of 75 female Japanese AN sufferers and 127 normal female control subjects revealed no significant association between the 5-HT2A promoter polymorphism and AN. Thus, at least for Japanese subjects, the A-allele of the -1438G/A polymorphism in the promoter region of the 5-HT2A receptor gene does not contribute to a predisposition to AN.

Analysis of tumor necrosis factor-alpha gene promoter polymorphisms in anorexia nervosa

Elevated plasma tumor necrosis factor-alpha (TNFalpha) levels and enhanced spontaneous TNFalpha release from peripheral blood mononuclear cells in patients with anorexia nervosa (AN) have been reported. TNFalpha activates the hypothalamic-pituitary-adrenal axis and reduces food intake, which is characteristic of eating disorders. Recently, three novel polymorphisms in the 5'-flanking region of the TNFalpha gene were reported at positions -1031 (T --> C substitution), -863 (C --> A) and -857 (C --> T). Differences in these alleles are reportedly related to altered TNFalpha-transcriptional promoter activity. Therefore, we performed a case-control association analysis to determine whether any of those three polymorphisms in the TNFalpha promoter region were involved in a predisposition to AN. The results of our analysis of a cohort of 79 female Japanese AN sufferers and 127 normal female control subjects provide no support for the hypothesis that -1031T/C, -863 C/A and -857C/T polymorphisms in the TNFalpha gene promoter region influence the susceptibility to AN.

Aberrant brain activation following motor skill learning in schizophrenic patients as shown by functional magnetic resonance imaging

BACKGROUND

Motor skill learning may be impaired in schizophrenia. While functional brain imaging studies have shown reduced activation during motor task performance in schizophrenic patients, brain activity changes with motor skill learning in these patients have not been studied by functional imaging.

METHODS

A sequential complex motor task involving the right hand was performed by nine medicated schizophrenic patients and 10 age-matched healthy controls. Functional magnetic resonance images were obtained using a gradient echo, echoplanar imaging (EPI) pulse sequence before and after 1 week of training in performing the task.

RESULTS

Bilaterally, patients showed significantly less blood oxygenation level-dependent (BOLD) signal response in the premotor area (PMA) before beginning motor training than controls. BOLD signal response increased in the left PMA of schizophrenic patients after 1 week of motor training; in contrast, the signal decreased in the left PMA of control subjects. Training effects concerning the number of finger movement sequences achieved did not differ between groups. Daily neuroleptic dose did not significantly affect changes with training in BOLD signal response in the PMA.

CONCLUSIONS

These preliminary results suggest that schizophrenic patients have dysfunction of neural networks in areas including the PMA that are involved in executing a complex motor task. In terms of brain activity, motor learning may be less efficient or slower in the patients than in healthy subjects.

[Anorexia nervosa (AN)--epidemiology, cause, therapy, outcome]

The number of patients suffering from anorexia nervosa is rising steadily. More than 90 percent of patients are female in preadolescents or adolescents. AN is characterized by abnormal eating behavior and excessive loss of weight. The self-esteem is highly dependent on their body shape and weight. The purposes of behavior therapy for AN are to remove various types of avoidance behavior, to reestablish desirable eating behavior and social skill behavior. The course and outcome of AN are variable. Of patients admitted to our hospital to receive behavior therapy, 60 percent are mostly recovered, 30 percent exhibit a fluctuating pattern of weight gain followed by relapse, and 10 percent are chronically deteriorating course of the illness over many years. The long-term mortality from AN is about 6 percent.

Psychobehavioral and immunological characteristics of HTLV-1 carriers and non-carriers with persistently low natural killer cell activity

OBJECTIVE

To clarify the differences in immunological and psychobehavioral characteristics of HTLV-1 carriers and non-carriers with persistently low natural killer (NK) cell activity.

METHODS

The individuals with persistently low NK cell activity were divided into HTLV-1 carriers and non-carriers. NK cell activity, lymphocytic proliferation, lymphocyte subsets (CD4+, CD8+, CD16+, CD20+, CD56+), and psychobehavioral responses were examined.

PATIENTS

Of 296 outpatients with physical complaints, 30 patients with persistently low NK cell activity (10 HTLV-1 carriers and 20 HTLV-1 non-carriers) and 20 healthy controls negative for HTLV-1 antibody and with normal NK cell activity were randomly selected.

RESULTS

In HTLV-1 carriers with persistently low NK cell activity, no significant differences were observed in NK cell subsets (CD16+ and CD56+) and psychobehavioral responses compared with the healthy controls. In HTLV-1 non-carriers, NK cell subsets were significantly low, and depression, anxiety and fatigue were significantly greater than in healthy controls.

CONCLUSIONS

These findings suggest that persistently e low NK cell activity in HTLV-1 carriers might be reduced due to the HTLV-1 infection. On the other hand, the reduction in the NK cell activity in HTLV-1 non-carriers appears a to be related to depression, anxiety, and fatigue.

Characteristic regional cerebral blood flow patterns in anorexia nervosa patients with binge/purge behavior

OBJECTIVE

The authors' goal was to investigate the effect of imagining food on the regional cerebral blood flow (rCBF) of anorexia nervosa patients with and without habitual binge/purge behavior.

METHOD

The subjects included seven female patients with purely restrictive anorexia, seven female patients with anorexia and habitual binge/purge behavior, and seven healthy women. Single photon emission computed tomography examination was performed before and after the subjects were asked to imagine food. Changes in rCBF count ratios (percent change) were then calculated and compared. The subjects were also asked to assess their degree of fear regarding their control of food intake.

RESULTS

The anorexia nervosa patients with habitual binge/purge behavior had a significantly higher percent change in the inferior, superior, prefrontal, and parietal regions of the right brain than the patients with purely restrictive anorexia and the healthy volunteers. The patients with habitual binge/purge behavior also had the highest level of apprehension in regard to food intake.

CONCLUSIONS

Specific activation in cortical regions suggests an association between habitual binge/purge behavior and the food recognition process linked to anxiety in patients with anorexia nervosa.

Prevalence of anorexia nervosa and bulimia nervosa in a geographically defined area in Japan

OBJECTIVE

Little has been understood regarding the frequency of eating disorders in Japan. This study was designed to identify the prevalence of anorexia nervosa (AN) and bulimia nervosa (BN) in Japan.

METHOD

We asked doctors in all of the relevant medical facilities (130 hospitals and 1,326 clinics) in Niigata Prefecture to report patients with DSM-IV-diagnosed eating disorders who appeared or were admitted between 20-24 October 1997. The response rate was 94.4%.

RESULTS

The estimated point prevalences of AN and BN were 4.79 and 1.02, respectively, per 100,000 females. Specifically for the age group of 15-29 years, the prevalence of AN was 17.10 and that of BN 5.79.

DISCUSSION

The prevalence of AN and BN in Japan is lower than that for European Caucasian populations. This result may be due to cultural and ethnic differences and/or it may be a transient phenomenon.

Cytotoxic alkaloids of Pachysandra terminalis

Four steroidal alkaloids, epipachysamines B (1) and E (2), pachystermine A (3) and pachysamine E (4), were isolated as cytotoxic principles from the MeOH extract of the stems of Pachysandra terminalis SIEB. et ZUCC. (Buxaceae). These alkaloids showed cytotoxic activity against P388 and P388/ADR leukemia cells in vitro. Three of the alkaloids (1-3) were previously isolated from this plant material, and this is the first report of their cytotoxic activity. Pachysamine E (4) is a new alkaloid.

Psychosocial and clinical factors predicting resumption of work following acute myocardial infarction in Japanese men

We investigated psychosocial and clinical factors related to work resumption, delay in returning to work and level of work activity after an acute myocardial infarction in Japanese male patients. A total of 111 married male patients experiencing a first acute myocardial infarction, aged less than 66 years and in full-time employment participated. Interviews and questionnaires were administered during hospitalization to assess potential predictors of work-related outcomes, with follow-up (81.6%) after an average of 8 months. We found that failure to return to work was predicated independently by older age (P=0.019), an introverted personality (P=0.011) and the presence of depressive symptoms during hospitalization (P=0.031). Delay in returning to work was predicted by greater concerns about health (P=0.011), low social support (P=0.021), and a failure to recognise a link between stress, coping style and illness (P=0.001). Resuming work at a lower activity level than before infarction was associated with older age (P=0.008), higher health concerns (P=0.012), and patients' predictions of their lower work activity (P=0.001). Clinical indices of infarction size and disease severity did not predict work-related outcomes. We conclude that psychosocial factors are associated with work resumption in Japanese men characterised by a job-centred lifestyle, with different factors being important for different work outcomes. The psychosocial factors found to be important are similar to those identified in Western societies.

Gamma-mangostin, a novel type of 5-hydroxytryptamine 2A receptor antagonist

Gamma-mangostin, purified from the fruit hull of the medicinal plant Garcinia mangostana caused a parallel rightwards shift of the concentration/response curve for the contraction elicited by 5-hydroxytryptamine (5-HT) in the rabbit aorta (pA2 = 8.2) without affecting the contractile responses to KCl, phenylephrine (alpha1) or histamine (H1). The perfusion pressure response of rat coronary artery to 5-HT (5-HT2A) was reduced concentration dependently by gamma-mangostin (IC50 = 0.32 microM). 5-HT amplified, ADP-induced aggregation of rabbit platelets (5-HT2A) was inhibited by gamma-mangostin (IC50 = 0.29 microM), whereas that induced by thrombin was not affected, nor did gamma-mangostin affect 5-HT-induced contraction of the guinea-pig ileum (5-HT3)in the presence of 5-HT1, 5-HT2 and 5-HT4 receptor antagonists. Furthermore, 5-HT-induced contraction of the rat fundus (5-HT2B) and 5-HT-induced relaxation of the rabbit aorta in the presence of ketanserin (5-HT1) and carbachol-induced contraction of the guinea-pig ileum (muscarinic M3) were not affected by gamma-mangostin (5 microM). Gamma-mangostin inhibited [3H]spiperone binding to cultured rat aortic myocytes (IC50 = 3.5 nM). The Kd for [3H]spiperone binding was increased by gamma-mangostin (3 nM) from 11.7 to 27.4 nM without affecting Bmax. These results suggest that gamma-mangostin is a novel competitive antagonist, free from a nitrogen atom, for the 5-HT2A receptors in vascular smooth muscles and platelets.

I-123 iomazenil SPECT in patients with mental disorders

The purpose of this study is visual evaluation of the distribution of I-123 iomazenil in the brains of patients with various types of mental disorder and to examine whether chronic administration of a clinical dose of benzodiazepine (BZ) affects the binding of I-123 iomazenil to BZ receptors (BZR). The subjects were 10 patients with mental disorders (3 males and 7 females) with a mean age of 26.8 yrs (range 19-39 yrs). Four of 10 patients were administered BZ for over 3 months and the other six were free of BZ for over one month. The SPECT images were obtained at 5-25 min (early) and 170-190 min (delayed), after the bolus i.v. injection of 167 MBq of I-123 iomazenil, with a triple-head gamma camera. The images were visually evaluated and the washout ratios of each region were calculated. In visual analysis, abnormalities were recognized in 5 patients on the delaye SPECT. The abnormalities were recognized more frequently in the superior frontal lobe. The washout ratio was higher in the BZ (+) patient group than in the BZ (-) patient group. I-123 iomazenil is useful, because the SPECT image with I-123 iomazenil reflects the distribution of BZR on the brain and provides the different information from that obtained with perfusion SPECT, X-ray CT or MRI. The rapid washout of I-123 iomazenil from the brains of BZ (+) patients suggests that chronic administration of a clinical dose of BZ affects the binding of I-123 iomazenil to BZR.

A novel class of potent gamma-aminobutyric acid aminotransferase inhibitor, 3-(hydroxyamino)propylamine and analogues

Hydroxyamino analogues of gamma-aminobutyric acid (GABA) were synthesized and evaluated for inhibitory activity toward gamma-aminobutyric acid aminotransferase (GABA-T). The title compound, 3-(hydroxyamino)propylamine (HPA), showed a potent inhibitory activity. The inhibition is competitive with respect to GABA and the Ki value of GABA-T for HPA is 0.4 mmol. The activity of inhibition is comparable to those of aminoxyacetic acid and valproic acid. 3-(Hydroxyaminomethyl)piperidine (3HMP), a cyclic analogue of HPA, also showed a potent inhibitory activity, whereas 3-(methoxyamino)propylamine (OMe-HPA), 3-(N-hydroxy-N-methylamino)propylamine (NMe-HPA) and 4-(hydroxyamino)piperidine (4HP) showed weak activity.

[Novel types of receptor antagonists from the medicinal plant Garcinia mangostana]

A crude methanolic extract of the fruit hull of Garcinia mangostana L. inhibited the contraction of the isolated rabbit aorta induced by histamine and serotonin. The extract has been fractionated by silica gel chromatography, monitoring the pharmacological activity to give active compounds. On the basis of physicochemical data, the active substances were identified as alpha-mangostin and gamma-mangostin. To define the pharmacological properties of alpha-mangostin, the effect of alpha-mangostin on both histamine H1 and H2 receptors were examined by monitoring the mechanical responses of smooth muscles and measuring the radioligand binding to cultured vascular smooth muscle cells. The results suggest that alpha-mangostin acts as a selective and competitive histamine H1 receptor antagonist. The pharmacological actions of gamma-mangostin on 5-HT receptors were also investigated by using contractile response of vascular smooth muscle, platelet aggregation and radioligand binding studies. The results provide the evidence that gamma-mangostin is a selective and competitive 5-HT2A receptor antagonist. It is of great interest that the structures of alpha-mangostin and gamma-mangostin free from nitrogen atom are not resemble to the common structures of histamine and serotonin receptor antagonists. alpha-Mangostin and gamma-mangostin may become novel types of lead compounds for histamine and serotonin receptor antagonists.

Pharmacological properties of alpha-mangostin, a novel histamine H1 receptor antagonist

In the isolated rabbit thoracic aorta and guinea-pig trachea, alpha-mangostin inhibited histamine-induced contractions in a concentration-dependent manner in the presence or absence of cimetidine, a histamine H2 receptor antagonist. But KCl-, phenylephrine- or carbachol-induced contractions were not affected by alpha-mangostin. The concentration-contractile response curve for histamine was shifted to the right in a parallel manner by alpha-mangostin. In the presence of chlorpheniramine, a histamine H1 receptor antagonist, alpha-mangostin did not affect the relaxation of the rabbit aorta induced by histamine. In the guinea-pig trachea, alpha-mangostin had no effect on the relaxation induced by dimaprit, a histamine H2 receptor agonist. alpha-Mangostin caused a concentration-dependent inhibition of the binding of [3H]mepyramine, a specific histamine H1 receptor antagonist to rat aortic smooth muscle cells. Kinetic analysis of [3H]mepyramine binding indicated the competitive inhibition by alpha-mangostin. These results suggest that alpha-mangostin is a novel competitive histamine H1 receptor antagonist in smooth muscle cells.

Histaminergic and serotonergic receptor blocking substances from the medicinal plant Garcinia mangostana

A crude methanolic extract of the fruit hull of Mangosteen, Garcinia mangostana L. inhibited the contractions of isolated thoracic rabbit aorta induced by histamine and serotonin. The extract of the fruit hull has been fractionated by silica gel chromatography, monitoring the pharmacological activity to give alpha- and gamma-mangostin. On the basis of pharmacological data, it is suggested that alpha-mangostin and gamma-mangostin are a histaminergic and a serotonergic receptor blocking agent, respectively.

The mode of inhibitory action of alpha-mangostin, a novel inhibitor, on the sarcoplasmic reticulum Ca(2+)-pumping ATPase from rabbit skeletal muscle

alpha-Mangostin, the principal ingredient of the fruit hull of Garcinia mangostana, caused a concentration-dependent decrease in the activities of both Ca(2+)-ATPase and Ca(2+)-transport of the sarcoplasmic reticulum from rabbit skeletal muscle with an IC50 value of 5 microM. Neither Ca2+ release nor other enzyme activities were affected by alpha-mangostin. Kinetic analysis of the inhibitory effects of alpha-mangostin on Ca(2+)-ATPase suggests that the inhibition of the ATPase is a noncompetitive-type with respect to ATP or Ca2+. alpha-Mangostin may become a useful pharmacological tool for clarifying the physiological functions of Ca(2+)-pumping ATPase and sarcoplasmic reticulum.

The culture fluid of Isaira japonica yasuda augments anti-sheep red blood cell antibody response in mice

Isaria japonica YASUDA was cultured in a liquid medium, and its culture fluid (IJCE) was tested for stimulatory activity to humoral antibody production. IJCE significantly enhanced the production of anti-sheep red blood cell (SRBC) plaque forming cells (PFC) by oral ingestions at 10 and 30 mg/kg/d for 4 consecutive days, either before or after SRBC challenge. It also recovered the reduction of anti-SRBC PFC response and number of spleen cells caused by treatment with 5-fluorouracil. It is suggested that IJCE is a promising source for an immunomodulating tool or medicine.

Changes in taste responsiveness in patients with anorexia nervosa during behavior therapy

We evaluated the changes in taste responsiveness of anorexia nervosa (AN) patients during behavior therapy. Taste responsiveness of AN patients was lower at admission when compared to controls but it improved significantly over the course of treatment (p < 0.01). Taste responsiveness improved prior to increase in body weight. No significant correlation was noted between weight gain and improvement in taste responsiveness. The period required to reach a food intake of 1600 Kcal/day and the duration of hospitalization were highly correlated (r = 0.72, p < 0.05). Those who reached 1600 Kcal/day earlier showed more rapid improvements in taste responsiveness. These results suggest that decreased taste responsiveness in AN patients can rapidly improve and such early improvement may result in better progression of treatment.

Clinical features of patients with anorexia nervosa: assessment of factors influencing the duration of in-patient treatment

We investigated that factors affecting the duration of in-patient treatment of patients with anorexia nervosa by comparing pretreatment clinical features with the length of hospitalization in 55 patients. Only patients who had completed the entire course of treatment were included in our analysis. Longer hospitalization was correlated with: poor social adaptation; anxiety and/or personality disorders before onset; older age at onset; older age at admission to our hospital; lower minimum body weight after onset; lower body weight at admission; longer duration of illness; frequent previous hospital treatment and/or history of in-patient treatment for anorexia nervosa or other somatic disorders after onset; habitual stimulant (alcohol, coffee and/or cigarettes) abuse; and a history of stealing after onset. Step-wise regression analysis revealed that minimum body weight after onset and age at admission explained 47% of the variance in the duration of in-patient treatment. We also describe the nature of in patient treatment typically offered to patients with anorexia nervosa in Japan.

Percutaneous intracavitary antifungals for a patient with pulmonary aspergilloma; with a special reference to in vivo efficacies and in vitro susceptibility results

A 61-year-old man with pulmonary aspergilloma received two antifungals intracavitarily. Although clinical, serological and roentgenographic improvement were observed with fluconazole therapy, bronchial secretions continuously yielded Aspergillus fumigatus. When fluconazole was switched to amphotericin B, the pathogen was eradicated immediately. The minimal inhibitory concentrations (MICs) of the isolate were 400 micrograms/ml for fluconazole, and 0.2 microgram/ml for amphotericin B. Although the discrepancy between in vitro and in vivo efficacy of antifungals has been argued, it was suggested the drug of choice should be selected on the basis of the MIC results at least in the intracavitary antifungal therapy for pulmonary aspergilloma.

Comparison of regional cerebral blood flow in patients with eating disorders

We used single photon emission computed tomography (SPECT) with Tc-99m-HMPAO to examine the characteristics of regional cerebral blood flow (rCBF) in five patients with bulimia nervosa (BN), eight patients with anorexia nervosa (AN), and in nine healthy controls. The SPECT examinations were performed before and after food intake stimulus, and the values of the corrected ratio (R) for rCBF in 10 cerebral cortical regions before (Rbefore) and after eating (Rafter) were calculated. The asymmetry indices (AI) of the R values for the left and right side of each cortical region and the percent change from Rbefore to Rafter (%change) were computed. In comparison with the other two groups, BN patients showed significantly higher Rbefore values in the bilateral inferior frontal and left temporal regions. The AN patients showed significantly lower Rbefore values in the left parietal region than the control group. There were no significant differences in Rafter values among the three groups. The %change values in the AN group showed the greatest increase in 9 out of the 10 regions. In contrast to the positive values obtained from the 10 regions observed in the AN group, 5 out of the 10 regions in the BN group showed negative values. Among the three groups, significant differences in %change were observed on both sides of the inferior frontal, temporal, parietal, and occipital regions. These findings indicate that differences in cerebral function of BN and AN patients can be characterized through SPECT imaging.

Confluentic acid and 2'-O-methylperlatolic acid, monoamine oxidase B inhibitors in a Brazilian plant, Himatanthus sucuuba

Monoamine oxidase B (MAO-B) inhibitors were isolated from the bark of a Brazilian plant, Himatanthus sucuuba (SPR.). Assignments of the 1H- and 13C-NMR data using two dimensional (2D)-NMR techniques showed the active components to be known lichen depsides, confluentic acid (1) and 2'-O-methylperlatolic acid (2). The depside (1) showed selective inhibition of MAO-B with IC50 value of 0.22 microM.

Evaluation of depression in rats exposed to chronic (unpredictable) electric shock

The present study was undertaken to evaluate the applicability of a proposed behavioral stress paradigm as an animal model for depression. Rats were trained to press a lever under a fixed ratio (FR) 5 schedule in a Skinner box for 10 days and were subsequently exposed to a daily regimen of 20 cycles of FR 5 and 10 cycles of variable ratio (VR) 10 for about a week. This exposure resulted in a reduction of the number of lever presses and successful escapes compared to the level achieved after training. In addition, weight gain was significantly suppressed compared with other treatments. Acute and chronic administration of psychotropic drugs (imipramine and chlordiazepoxide) showed that treatment with imipramine increased both the number of lever presses and successful escapes while chlordiazepoxide increased only the number of lever presses. The results suggest that this simplified animal model utilizing chronic unpredictable electric shock may be useful in the study of human depression.

Russuphelins B, C, D, E and F, new cytotoxic substances from the mushroom Russula subnigricans Hongo

Five new chlorinated phenyl ethers, russuphelins B (2), C (3), D (4), E (5) and F (6) have been isolated from the mushroom Russula subnigricans Hongo, and their structures were elucidated by spectroscopic and chemical means. Russuphelins B (2), C (3) and D (4) exhibited cytotoxic activity in vitro against P388 leukemia cells.

(2R), (1'R) and (2R), (1'S)-2-amino-3-(1,2-dicarboxyethylthio)propanoic acids from Amanita pantherina. Antagonists of N-methyl-D-aspartic acid (NMDA) receptors

An antagonist of NMDA-sensitive glutamate receptors in rat brain membrane and rat spinal motoneurones was isolated from Amanita pantherina and identified as a diastereoisomeric mixture of 2-amino-3-(1,2-dicarboxyethylthio)propanoic acids. The mixture was separated and the absolute configurations of the components were determined as (2R), (1'R) and (2R), (1'S), by analysis of the optical properties.

5-Lipoxygenase inhibitors isolated from the mushroom Boletopsis leucomelas (Pers.) Fayod

Terphenyl compounds, tentatively named Bl-I (1), Bl-II (2), Bl-III (3), Bl-IV (4) and Bl-V (5), showing 5-lipoxygenase inhibitory activity have been isolated from the mushroom Boletopsis leucomelas (Pers.) Fayod. On the basis of physico-chemical and spectral evidence, they were concluded to be a series of cycloleucomelone-leucoacetates.

Russuphelin A, a new cytotoxic substance from the mushroom Russula subnigricans Hongo

A new cytotoxic substance, designated russuphelin A (1), has been isolated from the mushroom Russula subnigricans Hongo (Basidiomycetes). The structure was elucidated as 2,6-bis(2,6-dichloro-4-hydroxyphenyloxy)-1,4-dimethoxy-benzene on the basis of spectroscopic data and confirmed by total synthesis.

Repandiol, a new cytotoxic diepoxide from the mushrooms Hydnum repandum and H. repandum var. album

Repandiol, a new cytotoxic diepoxide has been isolated from the mushrooms Hydnum repandum and H. repandum var. album. The chemical structure was elucidated as (2R,3R,8R,9R)-4,6-decadiyne-2,3:8,9-diepoxy-1,10-diol on the basis of spectroscopic analysis. The structure was confirmed by the synthesis of optically active repandiol. Repandiol displayed potent cytotoxic activity against various tumor cells.

Cytokine-related immunopotentiating activities of paramylon, a beta-(1-->3)-D-glucan from Euglena gracilis

Paramylon, a beta-(1-->3)-D-glucan, isolated from Euglena gracilis, was tested for its adjuvant activity on the antibody response to sheep red blood cell (SRBC) in mice. Paramylon markedly enhanced anti-SRBC plaque-forming cell production at a dose of 10 mg/kg. It was also found that in vitro addition of lipopolysaccharide in culture to macrophages from paramylon-treated mice produced a large amount of interleukin 1 (IL-1) and there was a significant level of interleukin 6 (IL-6) induced transiently in the blood of these mice. As IL-1 and IL-6 play crucial roles in the immune response to T cell-dependent antigens like SRBC, the immunopotentiating effect of paramylon might be expressed through the action of these cytokines.

Selective inhibition of T-cell-dependent immune responses by bisbenzylisoquinoline alkaloids in vivo

The bisbenzylisoquinoline (BBI) alkaloids, chondocurine, tetrandrine, isotetrandrine and cepharanthine, were tested for immunosuppressive activity in mice. A plaque-forming cell (PFC) response to a T-cell-dependent antigen, sheep red blood cell, was significantly suppressed by a 7 day treatment of chondocurine or tetrandrine at 1 mg/kg/day and of isotetrandrine at 50 mg/kg/day, but not suppressed by cepharanthine treatment. The suppressive effect of chondocurine was greater when it was given after immunization rather than before or concurrently. However, it did not affect the PFC response to a T-cell-independent antigen, lipopolysaccharide. A delayed-type hypersensitivity was also suppressed by chondocurine treatment. There was no significant change in lymphocyte number and proportion of T-cell subsets in the BBI alkaloid-treated mice. These data suggest that there is selective inhibition by chondocurine and tetrandrine of the T-cell-dependent immune reactions.

Inhibitory effect of bisbenzylisoquinoline alkaloids on the quick death of mice treated with BCG/LPS

Three bisbenzylisoqinoline alkaloids, chondocurine (Chon), berbamine (Ber), and cycleanine (Cyc) were tested for their protective effect on the quick death of mice primed with bacillus Calmette Guerin (BCG) and elicited with lipopolysaccharide (LPS). Seven-consecutive treatments with Chon or Cyc at a dose of 10 mg/kg following BCG priming resulted in significant improvement in the survival rate. A single dose of Chon also protected the BCG/LPS-treated mice from death if it was given immediately after, not 4 h after, LPS elicitation. These data show that bisbenzylisoquinoline alkaloids can protect mice from the lethal toxicity induced by the BCG/LPS combination treatment by inhibiting the priming with BCG or the elicitation with LPS.