Correlation between overexpression of c-met gene and the progression of gastric cancer

The c-met oncogene encodes a receptor of hepatocyte growth factor (HGF), which has both mitogenic and motogenic activities. We have studied the c-met gene expression in gastric cancer by immunohistochemical method using an antibody specific to the c-met beta-chain. c-met immunoreactivity was preferentially localize on the cell membrane, and 55 (43%) of 127 primary gastric cancers showed c-met immunoreactivity. Strong correlation was found between c-met expression in large tumors, lymph node involvement, serosal invasion, as well as peritoneal dissemination. Furthermore, c-met positive tumors had a tendency to metastasize to more distant lymph node sites. Regarding the macroscopic type, Borrmann type 4 gastric cancer showed the highest incidence (12/16, 76%) of positive c-met expression. Patients with c-met positive tumor ran a significantly poorer prognosis than those with c-met negative one. These results indicate that the c-met protein participates in the progression and invasion of stomach cancer, and that c-met tissue status is a useful biological marker in gastric cancer.

Efficient generation of recombinant adenoviruses using adenovirus DNA-terminal protein complex and a cosmid bearing the full-length virus genome

An efficient method of constructing recombinant adenoviruses (Ads) has been established. The expression unit to be introduced into recombinant Ad was first inserted into the unique Swa I site of the full-length Ad genome cloned in a cassette cosmid. The cassette bearing the expression unit was then cotransfected into human embryonic kidney 293 cells together with the Ad DNA-terminal protein complex digested at several sites with Eco T22I or Ase I/EcoRI. The use of the parent Ad DNA-terminal protein complex instead of the deproteinized Ad genome DNA allowed very efficient recovery of the desired recombinant Ad, and the above restriction digestion drastically reduced regeneration of the parent virus. Several hundred virus clones were readily obtained in each experiment, and about 70% of the clones were the desired recombinant viruses. Furthermore, because the cassette contained the full-length Ad genome, any position of the genome could be easily modified to develop a new vector design. We established construction systems for two types of Ad vectors, the E1-substitution type and the E4-insertion type. This method may greatly facilitate the application of recombinant Ads and should be useful for further improvement of Ad vectors.

Dexamethasone inhibits insulin binding to insulin-degrading enzyme and cytosolic insulin-binding protein p82

We recently demonstrated that insulin specifically binds to several cytosolic insulin-binding proteins (CIBPs) including insulin-degrading enzyme (IDE) and CIBP p82 in cytosol isolated from H35 rat hepatoma cells. Insulin binding to these CIBPs was regulated by culture conditions, such as serum or insulin. In the present study, we examined the effect of dexamethasone on insulin binding to CIBPs in H35 cells. When the cells were treated with 100 nM dexamethasone for 24 hrs, insulin binding to IDE and CIBP p82 was decreased by about 50% without decreasing the expression level of IDE. Insulin added with the dexamethasone prevented the steroid's effect. Furthermore, dexamethasone directly blocked insulin binding to CIBPs in isolated cytosol. These results suggest that dexamethasone, directly or as a complex with other proteins, binds to IDE and CIBP p82 and changes their ability to bind insulin, possibly by inducing a conformational change or by blocking insulin binding sites. IDE was recently identified as a receptor accessory factor for androgen and glucocorticoid receptors and plays an important role in the regulation of gene transcriptional responses. Combined with previous reports, our findings suggest IDE and other CIBPs such as CIBP p82 may play a role in the cross-talk between insulin and the signal transduction pathways of steroid hormones.

Plasma thrombomodulin: usefulness as a blood access failure marker in hemodialysis patients

In 144 patients on hemodialysis (76 males and 68 females, median age 55.7 +/- 14.1 years, mean period on dialysis 44.1 +/- 33.3 months), thrombomodulin was determined by enzyme immunoassay prior to initiation of hemodialysis. The results showed that the mean thrombomodulin value of hemodialysis patients was 13.59 +/- 3.63 ng/ml which was significantly higher than the control value (3.20 +/- 0.90 ng/ml). The thrombomodulin values were significantly higher in patients with blood access failure (15.27 +/- 4.45 ng/ml) than in those without (13.11 +/- 3.31 ng/ml), and the rate of blood access failures was also significantly higher in those with thrombomodulin values of 15.0 ng/ml or higher than in those with values < 15.0 ng/ml. It was evident that there is a higher risk of blood access failure in patients with severe systemic vascular endothelial injury, and thrombomodulin is a useful marker of such an injury.

Piperastatin A, a new selective serine carboxypeptidase inhibitor produced by actinomycete. I. Taxonomy, production, isolation and biological activities

Piperastatin A (structure, N-formyl-allo Ile-Thr-Leu-Val-Pip-Leu-Pip, Pip = hexahydropyridadine-3-carboxylic acid; molecular weight, 809), a new inhibitor of serine carboxypeptidase was discovered in the fermentation broth of Streptomyces lavendofoliae MJ908-WF13. It was purified by activated charcoal chromatography, YMC gel ODS-A chromatography and centrifugal partition chromatography (CPC) by monitoring its inhibitory activity against carboxypeptidase Y (CP-Y), and finally obtained as colourless needles. Piperastatin A is a competitive inhibitor of the enzyme with Ki = 52 +/- 6.2 nM. Piperastatin A is a highly specific inhibitor of the serine carboxypeptidases, CP-Y and platelet deamidase with little effect on related enzymes, has no antimicrobial activity and has low toxicity.

Intracellular ionic changes induced by bullous pemphigoid IgG subclasses

To ascertain whether membrane signal transduction is induced by bullous pemphigoid (BP) antibody and whether cell lysis is induced by its complement activation, we assessed the intracellular Ca2+ concentration ([Ca2+]i), intracellular pH, membrane potential and morphology of living cells by following the time course of fluorescence intensity of Fluo-3/AM, Snaff-1/AM, Dioc-5 and Luciffer yellow, respectively. A transient increase of Fluo-3 fluorescence intensity in DJM-1 cells (a squamous cell carcinoma line) was revealed when the cells were incubated with 2 of five IgG1 BP antibodies. However, no transient increase of Fluo-3 fluorescence intensity was revealed when the cells were incubated with IgG2 and IgG4 BP antibodies. A transient increase of Fluo-3 fluorescence intensity was revealed in DJM-1 cells incubated with 3 of seven IgG1 and 1 of four IgG2 BP antibodies in an EGTA-containing low-Ca2+ medium. On the other hand, the Dioc-5 fluorescence intensity did not change significantly, though the increase of Fluo-3 fluorescence intensity was observed. The increase of Snarf-1 fluorescence intensity was revealed in DJM-1 cells incubated with 2 of five IgG1 BP antibodies, but was not revealed in the cells incubated with IgG2 or IgG4 of BP antibodies. Study of complement activation by BP IgG1 showed a transient increase of Fluo-3 fluorescence intensity of with 3 of five IgG1 BP antibodies when DJM-1 cells were incubated with complement-supplemented normal-Ca2+ medium. At the same time, however, endocytosis and cell lysis were not observed with 2 IgG1 BP antibodies which did induce an increase of Fluo-3 fluorescence intensity when Lucifer-yellow-loaded DJM-1 cells were incubated with complement-supplemented normal-Ca2+ medium. We examined next whether anti-180 kD BP antigen monoclonal antibodies (mAbs R-223 and 233) induce an increase of Fluo-3 fluorescence intensity. MAb R-223 did not induce any increase of Fluo-3 fluorescence intensity in DJM-1 cells, when incubated with normal- and low-Ca2+ media However, mAb R-223 induced a transient increase of Fluo-3 fluorescence intensity in DJM-1 cells when incubated with complement-supplemented normal-Ca2+ medium. MAb 233 did not induced an increase of Fluo-3 fluorescence intensity in DJM-1 cells when incubated with normal- and low-Ca2+ media. These results suggest that the BP IgG1 induces Ca2+ release from intracellular storage sites, however, the complement activated by BP IgG1 does not induce cell lysis. It could not be confirmed that anti-180 kD BP antigen antibody induced Ca2+ release from intracellular storage sites.

Adaptation to high-salt stress in Saccharomyces cerevisiae is regulated by Ca2+/calmodulin-dependent phosphoprotein phosphatase (calcineurin) and cAMP-dependent protein kinase

Ca2+/calmodulin-dependent phosphoprotein phosphatase (calcineurin, PP2B) of Saccharomyces cerevisiae is implicated in adaptation to high-salt conditions. Calcineurin mediates high salt-induced expression of the ENA1/PMR2 gene encoding the P-type ATPase, which is suggested to be involved in Na+ efflux. We identified the PDE1 gene encoding the low-affinity cAMP phosphodiesterase as a multicopy suppressor of the Li(+)- and Na(+)-sensitive calcineurin null mutant, suggesting that cAMP is a negative regulator of adaptation to high-salt stress. Genetic analysis indicated that calcineurin and cAMP act antagonistically in a common pathway for adaptation. The bcy1 disruption, which leads to constitutive cAMP-dependent protein kinase (PKA) activity inhibited high NaCl-induced expression of the ENA1/PMR2 gene, caused an elevation of the intracellular Na+ level and a growth defect in high-NaCl medium, all of which were analogous to the defects of a calcineurin mutant. A reduced cAMP level resulting from multiple copies of the PDE1 gene caused increased expression of the ENA1/PMR2 gene in response to high NaCl. We propose a model for the regulation of cation homeostasis, in which calcineurin antagonizes PKA to activate transcription of the ENA1/PMR2 gene in response to high-salt conditions.

Possible participation of autocrine and paracrine vascular endothelial growth factors in hypoxia-induced proliferation of endothelial cells and pericytes

Hypoxia is the principal factor that causes angiogenesis. These experiments were conducted to explore how it induces the proliferation of vascular cells, a key step in angiogenesis. Human umbilical vein endothelial cells and bovine retinal pericytes were grown in controlled atmosphere culture chambers containing various concentrations of oxygen. The numbers of both endothelial cells and pericytes increased significantly under hypoxic conditions; the O2 concentrations that achieved maximal growth promotion were 10% for endothelial cells and 2.5% for pericytes. Quantitative reverse transcription-polymerase chain reaction analysis revealed that mRNAs coding for the secretory forms of vascular endothelial growth factor (VEGF), a mitogen specific to endothelial cells, were present in both endothelial cells and pericytes and that their levels increased significantly in the two cell types as the atmospheric O2 concentration decreased. The two genes for VEGF receptors, kinase insert domain-containing receptor (kdr) and fms-like tyrosine kinase 1 (flt1), were found to be constitutively expressed in endothelial cells, and their relative mRNA levels were ranked in that order. On the other hand, only flt1 mRNA was detected in pericytes under hypoxic conditions. Furthermore, most antisense oligodeoxyribonucleotides complementary to VEGF mRNAs efficiently inhibited DNA synthesis in endothelial cells cultured under hypoxic conditions. These results indicate that autocrine and paracrine VEGFs may take part in the hypoxia-induced proliferation of endothelial cells.

Insulin-induced egr-1 expression in Chinese hamster ovary cells is insulin receptor and insulin receptor substrate-1 phosphorylation-independent. Evidence of an alternative signal transduction pathway

Insulin's effects primarily are initiated by insulin binding to its plasma membrane receptor and the sequential tyrosine phosphorylation of the insulin receptor and intracellular substrates, such as insulin receptor substrate-1 (IRS-1). However, studies suggest some insulin effects, including those at the nucleus, may not be regulated by this pathway. The present study compared the levels of insulin binding, insulin receptor and IRS-1 tyrosine phosphorylation, and phosphatidylinositol 3'-kinase activity to immediate early gene c-fos and egr-1 mRNA expression in Chinese hamster ovary (CHO) cells expressing only neomycin-resistant plasmid (CHONEO), overexpressing wild type human insulin receptor (CHOHIRc) or ATP binding site-mutated insulin receptors (CHOA1018K). Insulin binding in CHONEO cells was markedly lower than that in other cell types. 10 nM insulin significantly increased tyrosine phosphorylation of insulin receptor and IRS-1 in CHOHIRc cells. Phosphorylation of insulin receptor and IRS-1 in CHONEO and CHOA1018K cells was not detected in the presence or absence of insulin. Similarly, insulin increased phosphatidylinositol 3-kinase activity only in CHOHIRc cells. As determined by Northern blot, nuclear run-on analysis, and in situ hybridization, insulin induced c-fos mRNA expression, through transcription, in CHOHIRc cells but not in CHONEO and CHOA1018K cells, consistent with previous reports. In contrast, all three cell types showed a similar insulin dose-dependent increase of egr-1 mRNA expression through transcription. These data indicated that insulin-induced egr-1 mRNA expression did not correlate with the levels of insulin binding to insulin receptor or phosphorylation of insulin receptor and IRS-1. These results suggest that different mechanisms are involved in induction of c-fos and egr-1 mRNA expression by insulin, the former by the more classic insulin receptor tyrosine kinase pathway and the latter by a yet to be determined alternative signal transduction pathway.

Xanthogranulomatous cholecystis. Cell composition and a possible pathogenetic role of cell-mediated immunity

Thirty-three cases of xanthogranulomatous cholecystitis (XGC) exhibiting the typical morphologic features were studied by light and electron microscopy and immunohistochemical techniques. Incidence of XGC was 4.2% of the surgically resected gallbladder diseases. Histologically, the granulomatous lesion of XGC principally consisted of accumulations of foam cells and lymphocytes. Variable numbers of multinucleated giant cells, granulocytes and fibroblastic cells were also noted. With respect to the origin of foam cells, it was considered that the vast majority of foam cells were derived from monocytes/macrophages because they were invariably positive for KP1, HAM56, CD11b and CD68. Interspersed among macrophage foam cells, many T lymphocytes were identified. The subtyping of T cells indicated a heterogenous population composed of both CD4+ and CD8+ lymphocytes typically in a ratio of 1:2. Macrophages and T lymphocytes demonstrated a marked expression of HLA-DR antigen. Electron microscopic and immunohistochemical double-staining observation demonstrated intimate apposition of T lymphocytes to macrophages or macrophage foam cells. The results indicate that XGC is a granulomatous disorder characterized by accumulations of macrophage foam cells and T cells. Delayed type hypersensitivity reaction of cell-mediated immunity may be implicated in the pathogenesis of XGC.

Complete amino acid sequence of a zinc metalloendoprotease from Streptomyces caespitosus

We determined the complete amino acid sequence of a zinc metalloendoprotease from Streptomyces caespitosus (ScNP). Peptide fragments obtained by digestion of Rcm-ScNP with trypsin, ScNP and endoproteinase Asp-N were purified by reverse-phase HPLC and their amino acids were analyzed using an automatic sequencer. ScNP consisted of a single polypeptide chain of 132 amino acid residues with one disulfide bond between residues 99 and 112 (M(r) 14376). Thus, the number of amino acid residues determined for this enzyme is much lower than the number of residues previously reported for metalloendoproteases. The amino acid sequence indicated that although ScNP has the zinc-binding motif. His-Glu-Xaa-Xaa-His, which is found at the active site of most zinc metalloendoproteases, it does not share overall significant similarity to the sequences of other zinc metalloendoproteases. Moreover, an analysis of the X-ray structure of ScNP at 0.2-nm resolution (Kirisu et al., unpublished results) revealed that Asp93, together with two histidine residues in the zinc-binding motif (His83 and His87) and a water molecule, is a zinc ligand. We propose that ScNP, which bears the HEXXHXXGXXD motif, represents a novel subfamily of zinc-containing metalloendoproteases.

A histologically distinctive interstitial pneumonia induced by overexpression of the interleukin 6, transforming growth factor beta 1, or platelet-derived growth factor B gene

Interstitial pneumonia is characterized by alveolitis with resulting fibrosis of the interstitium. To determine the relevance of humoral factors in the pathogenesis of interstitial pneumonia, we introduced expression vectors into Wistar rats via the trachea to locally overexpress humoral factors in the lungs. Human interleukin (IL) 6 and IL-6 receptor genes induced lymphocytic alveolitis without marked fibroblast proliferation. In contrast, overexpression of human transforming growth factor beta 1 or human platelet-derived growth factor B gene induced only mild or apparent cellular infiltration in the alveoli, respectively. However, both factors induced significant proliferation of fibroblasts and deposition of collagen fibrils. These histopathologic changes induced by the transforming growth factor beta 1 and platelet-derived growth factor B gene are partly akin to those changes seen in lung tissues from patients with pulmonary fibrosis and markedly contrast with the changes induced by overexpression of the IL-6 and IL-6 receptor genes that mimics lymphocytic interstitial pneumonia.

Reversal of drug sensitivity in MDR subline of P388 leukemia by gene-targeted antisense oligonucleotide

We attempted to reverse multidrug resistance (MDR) by treatment with 25-mer antisense phosphorothioate oligonucleotide. The phosphorothioate analogs, the sequences of which are sense or antisense to the initiation codon of mouse mdr1 mRNA, were tested against murine leukemic P388/S and adriamycin-resistant P388/ADR cell lines. A weak inhibitory effect on the growth of P388/S and P388/ADR cells was observed at a sense and antisense oligonucleotide concentration of 30 microM. Using the monoclonal antibody to P-glycoprotein and a flow cytometry technique, we showed that the level of expression of P-glycoprotein in P388/ADR cells treated with antisense oligonucleotide was lower than when treated with sense oligonucleotide. The antisense oligonucleotide potentiated the growth-inhibitory effect of vinblastine on P388/ADR cells, whereas sense oligonucleotide did not. This was accompanied by an increase in vinblastine retention in the cells. The reversal of the resistance by antisense oligonucleotide was increased by the combination with 1 microM verapamil. These results suggest that the antisense oligonucleotide and low dose verapamil may be useful in circumventing the resistance to anticancer drugs of MDR tumors.

[Reproductive toxicity of iodixanol, a new non-ionic, iso-tonic contrast medium in rats and rabbits]

The reproductive toxicity of iodixanol, a non-ionic isotonic contrast medium, was investigated in rats and rabbits. Iodixanol was administered intravenously to male rats at doses of 0.3, 1.0 or 2.0 gI/kg/day for 80 days or more until successful copulation. Female rats were treated with iodixanol at the same dose levels for at least 14 days prior to and in the early stage of pregnancy. No remarkable adverse effects on fertility were noted at any dose level. Increased water consumption and swollen paws/face were observed among male rats receiving > 1.0 gI/kg/day. In addition, decreased food consumption was observed in males of the 2.0 gI/kg/day group. In female rats, no remarkable adverse effects were noted at any dose level. Iodixanol elicited no evidence of teratogenicity when administered during the fetal organogenesis period to pregnant rats and rabbits at doses of 0.3, 1.0 or 2.0 gI/kg/day. No remarkable changes were observed in rat or rabbit fetuses, nor in dams of any dose group. In a perinatal and postnatal dosing study in rats using doses of 0.3, 1.0 or 2.0 gI/kg/day, iodixanol did not adversely affect the reproductive performance of the treated parent animals and pre- and postnatal development of their offspring.

Chlordiazepoxide attenuates stress-induced activation of neurons, corticotropin-releasing factor (CRF) gene transcription and CRF biosynthesis in the paraventricular nucleus (PVN)

Corticotropin-releasing factor (CRF) plays a role in coordinating endocrine, autonomic, and behavioral responses to stressful stimuli. Benzodiazepines exert many effects which oppose those of CRF, including anxiolysis and suppression of the pituitary-adrenal axis. In the present study, we employed in situ analysis of CRF heteronucleous RNA (hnRNA) and c-fos mRNA to assess stimulus-induced CRF gene transcription rate following stress and its modulation by chlordiazepoxide (CDP). Male albino rats were exposed to restraint stress for 30 min and sacrificed 30 and 120 min after the onset of stress. Either CDP or vehicle was given intraperitoneally 60 min before stress. To determine plasma ACTH levels by immunoradiometric assay, another group of rats was decapitated 10 min after the onset of restraint stress. Restraint stress induced rapidly and significantly c-fos mRNA and CRF hnRNA expression in the PVN at the 30 min time point. Increases in both RNA copies were significantly inhibited by administration of CDP at doses of 5 and 10 mg/kg. CRF mRNA concentrations were increased significantly in the PVN 120 min after stress and again, CDP attenuated significantly these increases in the PVN. The plasma ACTH increase in response to stress was inhibited significantly by CDP administration at every dose tested. CDP did not change CRF mRNA levels in the non-stressed animal.(ABSTRACT TRUNCATED AT 250 WORDS)

Renal osteodystrophy in hemodialysis patients

Patterns of bone loss in the axial and appendicular skeleton were studied in 88 chronic hemodialysis patients (59 males and 29 females) and 60 normal volunteers (30 males and 30 females). The hemodialysis patients were properly medicated with phosphate binders and 1 alpha-OH D3 where necessary. The metacarpal index (MCI), sigma gray scale/diameter (sigma GS/D) and bone mineral content (BMC) were measured as bone mass indices, and the relationship investigated between clinical factors [age, duration of hemodialysis, serum phosphate (P), calcium (Ca), carboxy-terminal fragments of parathyroid hormone (C-PTH), osteocalcin (OC), alkaline phosphate (ALP) and Ca x P]. The bone loss in the hemodialysis patients was greater than that in the normal controls and was accelerated after menopause in women. However, the bone mass indices in a few of the hemodialysis patients of advanced age (over 60) showed higher values than those of the controls. The bone mass indices in male hemodialysis patients showed a negative correlation with the hemodialysis duration, C-PTH and OC, as did those in female patients with hemodialysis duration. On the other hand, BMC in female hemodialysis patients showed a negative correlation with P, C-PTH and Ca x P. In conclusion, age and the duration of hemodialysis are the most essential factors in skeletal and trabecular bone loss in male and female hemodialysis patients. Subsequent factors responsible for skeletal bone loss in male patients are C-PTH and OC, and those for trabecular bone loss in female patients are P, C-PTH and Ca x P. Control of the levels of C-PTH, OC, P and Ca x P is recommended for prevention of bone loss in hemodialysis patients.

Isolation of human T-cell leukemia virus type I from a transformed T-cell line derived spontaneously from lymphocytes of a seronegative Egyptian patient with mycosis fungoides

Mycosis fungoides (MF) is a rare form of cutaneous T-cell lymphoma that may be associated with human T-cell leukemia virus type I (HTLV-I) infection. Using the polymerase chain reaction, the HTLV-I pX region was constantly detected in the genomic DNA extracted from peripheral blood mononuclear cells (PBMCs) of an HTLV-I antibody-seronegative Egyptian MF patient enrolled in a study to isolate HTLV-I from North Africa. A CD4+ and interleukin-2 (IL-2) receptor-positive T-cell line was established when the phytohemagglutinin-stimulated PBMCs of that patient were maintained in IL-2-containing culture medium. The cell line (EMF) was initially IL-2 dependent and then became IL-2 independent after gradual withdrawal of the IL-2. The cells reacted positively with monoclonal antibodies specific for the HTLV-I Env or HTLV-I Gag proteins. Using the Southern blot analysis, HTLV-I provirus could be detected in the genomic DNA extracted from the EMF cells. Limited nucleotide sequence of the env region showed more than 95% homology between the EMF provirus and other known HTLV-I isolates. Western blot analysis of the cell lysates showed the expression of the HTLV-I structural proteins. These data imply that a transforming HTLV-I provirus may be present, at least in certain cases of MF, regardless of the presence or absence of the specific antibodies.

Receptor-mediated toxicity to pericytes of advanced glycosylation end products: a possible mechanism of pericyte loss in diabetic microangiopathy

The influence of advanced glycosylation end products (AGE) on bovine retinal pericytes was investigated. When pericytes were cultured with AGE-bovine serum albumin (BSA), pericyte growth was significantly retarded in a dose-dependent manner. They also exhibited an immediate toxicity to pericytes. However, MRC-5 human fibroblasts were totally resistant to AGE-BSA. Moreover, antisense oligonucleotides complementary to mRNA coding for AGE receptor were found to reverse the AGE-induced decrease in viable pericyte number, although the mRNA level was about one order of magnitude lower in pericytes than in the fibroblasts. These results indicate that pericytes may possess a peculiar sensitivity to AGE, and that AGE ligand-receptor interactions may play an important role in the pathogenesis of pericyte loss, the principal change in diabetic microangiopathies.

[A case of atopic dermatitis treated with stellate ganglion block--the change of serum IgE and blood eosinophil levels]

Stellate ganglion block (SGB) therapy was tried on a patient with severe adult type atopic dermatitis. SGB was performed 102 times in total and clinical symptoms improved gradually. Serum IgE and blood eosinophil levels, which correlate with disease severity, increased gradually following repeated SGB. After a series of SGB was stopped, clinical symptoms became worse and serum IgE and blood eosinophil levels increased again. We conclude that although SGB is presumably one of the effective therapies for severe adult type atopic dermatitis, it might be difficult to improve atopic constitution entirely because the patient was not cured completely following repeated SGB.

Male reproductive toxicity study of nefiracetam in rats

Sprague-Dawley male rats were administered nefiracetam orally at daily doses of 500 and 1500 mg/kg/day for 4 or 9 weeks. Although the copulation index was not affected by nefiracetam treatment, the fertility index was extremely low in the 1500 mg/kg/day group for both treatment periods. This high dose group consistently exhibited decreased testicular weights. Epididymal and prostate weights were also reduced in the 1500 mg/kg/day group after both 4- and 9-week treatments and in the 500 mg/kg/day group after the 9-week treatment. Severe degenerative changes such as degeneration of germ cells, loss of germ cells and atrophy of seminiferous tubules were observed in all rats of the 1500 mg/kg/day groups after both 4 and 9 weeks of treatment. Retention of spermatids in stage IX, X and XI seminiferous tubules was also noted after the 4- and 9-week treatments at 500 mg/kg/day. The testicular sperm head counts were markedly decreased following the 4- and 9-week treatments at 1500 mg/kg/day, and mildly reduced after the 4-weeks treatment at 500 mg/kg/day. From these results it is concluded that histopathological examination and the testicular sperm head count method are highly useful for detecting testicular toxicity and that testicular lesions caused by nefiracetam can be detected after 4 weeks of exposure.

Alcohol and aldehyde dehydrogenase genotypes and drinking behavior of Chinese living in Shanghai

Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), the principal enzymes responsible for oxidative metabolism of ethanol, exist in multiple, genetically determined molecular forms. Widely different kinetic properties in some of these isozymes account for the individual differences in alcohol sensitivity. In this study we used the polymerase chain reaction/restriction fragment length polymorphism method to determine the genotypes of the ADH2 and ALDH2 loci of alcoholic and nonalcoholic Chinese living in Shanghai. We also investigated the subjects' drinking patterns by means of semistructured interviews. The alcoholics had significantly lower frequencies of the ADH2(2) and ALDH2(2) alleles than did the nonalcoholics, suggesting the inhibitory effects of these alleles for the development of alcoholism. In the nonalcoholic subjects, ADH2(2) had little, if any, effect, despite the significant effect of the ALDH2(2) allele in decreasing the alcohol consumption of the individual. Taken together, these results fit the proposed hypothesis for the development of alcoholism, i.e., drinking behavior is greatly influenced by the individual's genotypes of alcohol-metabolizing enzymes, and the risk of becoming alcoholic is proportionate with the ethanol consumption of the individual.

Changing pattern of mental health utilization in Hachijojima

We have reviewed retrospectively 229 patients interviewed by the mental health team in the Hachijojima since the establishment of our services in 1987. The 6 year observation period was classified into three chronological stages for the purposes of identifying any change in the utilization pattern of the mental health services of the island. The rate of schizophrenia was observed to have decreased from 48% in the first 2 years of the study period to 28% in the last 2 years; while that of other mental disorders increased yearly. Interestingly, an increasing number of patients were referred to our services by professionals in areas other than mental health (from 42 to 77%), and patients without any history of psychiatric treatment were more frequently seen (from 36 to 75%) in the later part of the study period. These changes suggest the importance of access to mental health services.

Stress-induced activation of neuronal activity and corticotropin-releasing factor gene expression in the paraventricular nucleus is modulated by glucocorticoids in rats

Intronic in situ hybridization methodology provides a means of determining the rate of gene transcription under basal and stimulated conditions. In the present study, we have used intronic in situ hybridization to the corticotropin-releasing factor (CRF) gene to measure hypothalamic CRF gene transcription after stress as well as its modulation by glucocorticoids. Using this and conventional exonic in situ hybridization we examined the time course of changes in c-fos mRNA, and CRF heteronuclear RNA (hnRNA) and mRNA concentrations in the paraventricular nucleus (PVN) of male Wistar rats after restraint stress. In addition, we determined the effects of adrenalectomy and dexamethasone administration on c-fos and CRF gene expression in the PVN. Restraint stress induced a rapid induction (within 5 min) of c-fos mRNA and CRF hnRNA expression in the PVN. Both RNA concentrations peaked at 30 min then decreased and were undetectable 2 h after stress onset. In contrast, the concentration of CRF mRNA increased gradually and a significant elevation was first detected 60 min after the beginning of stress. Adrenalectomy augmented and dexamethasone pretreatment inhibited c-fos mRNA, CRF hnRNA, and mRNA induction after stress. The data suggest that stress-induced activation of neurons, CRF gene transcription, and CRF synthesis in the PVN are modulated by glucocorticoids.

TAN-1511 A, B and C, microbial lipopeptides with G-CSF and GM-CSF inducing activity

The microbial lipopeptides, TAN-1511 A, B and C, were isolated from the culture broth of Streptosporangium amethystogenes subsp. fukuiense AL-23456. Their structures were elucidated on the basis of their reactions and spectroscopic analyses. These lipopeptides were mixtures of molecules having different lengths of fatty acids. The metabolites stimulated the proliferation of bone marrow cells from BALB/c female mice at very low concentrations (concentration giving 30% increase: A and B, 0.313 ng/ml; C, 1.25 ng/ml). We confirmed that chemically synthesized TAN-1511 A analogue [(2R,6R)-2-tetradecanoylamino-6,7- bis(hexadecanoyloxy)-4-thiaheptanoyl-Gly-Gly-Gly-Glu-Thr-Thr -OH] stimulated the proliferation of bone marrow cells in a manner similar to that of natural TAN-1511 A. This analogue induced the secretion of both granulocyte colony stimulating factor (G-CSF) and granulocyte-macrophage colony stimulating factor (GM-CSF), and potentiated the generation of Gr-1 positive cells in the bone marrow cell culture. Moreover, it effected the G-CSF mediated restoration of granulocytopoiesis in a murine leukopenia model.

Synthesis and biological activities of TAN-1511 analogues

TAN-1511 analogues were synthesized and their effects on the proliferation of bone marrow cells were examined. To exert potent activity the following conditions are necessary: the configuration of the 2-amino-6,7-dihydroxy-4-thiaheptanoic acid moiety must be (2R,6R), long chain acyl groups (C14 to C18) must be bound to both hydroxyl groups, the amino group must be free or acylated with the long chain fatty acid (ca. C14) and the peptide moiety must have glutamic acid as a component. Among the synthesized compounds, trisodium (2R,6R)-2-amino-6,7-bis (hexadecanoyloxy)-4-thiaheptanoyl glycyl glutamyl glutamate, which has improved solubility, was effective in experimental leukocytopenia in mice.