Vasopressin V1 receptor in rat hippocampus is regulated by adrenocortical functions

Two subtypes of arginine vasopressin (AVP) receptors (V1 and V2) have been distinguished. In this study, we examined the characteristics of AVP binding in rat hippocampus and the effects of bilateral adrenalectomy and adrenal steroids on its [3H]AVP binding. [3H]AVP binding to rat liver and the hippocampal membranes was strongly inhibited by the V1 antagonist, OPC-21268. ADX resulted in a significant decrease in the Bmax of AVP binding in the hippocampus. Chronic treatment with aldosterone and corticosterone restored the ADX-induced reduction, but treatment with dexamethasone did not. These results suggest that the AVP V1 receptor in the hippocampus is regulated by adrenocortical neuroregulatory functions.

Trichinella spiralis: recovery of newborn larvae from cardiac tissues

Newborn larvae (NL) of Trichinella spiralis in cardiac tissues were recovered by incubating cardiac tissue blocks of mice and gerbils infected with T. spiralis in RPMI- 1640 medium supplemented with antibiotics and 5% FCS for 24 h in a humidified atmosphere of 5% CO2 in air at 37 degrees C. This technique is effective for the recovery of migrating NL in visceral tissues which are en route to skeletal muscles, and may help to clarify the involvement of NL in the pathogenesis of cardiac or cerebral lesions in trichinellosis.

[Experience of fluconazole granules and injection in pediatric patients]

Fluconazole (FLCZ) is an antifungal agent of triazole class and has been proven to be effective against deep-seated mycosis caused by Candida spp., Aspergillus spp. and Cryptococcus spp. This time, as we had an opportunity to use fluconazole granules, a new dosage form of the agent, we investigated its efficacy and safety in children with deep-seated mycosis together with the efficacy of the injectable form of the agent. FLCZ was administered to 6 patients with fungal infections for treatment and 5 compromised hosts with a high risk of fungal infections for evaluation of its prophylactic effect. The patients enrolled in the study were 11 in total, of whom 6 patients were evaluated for efficacy: fungal phlegmon in 2, esophageal candidiasis in 2, fungal bronchitis in 1 and oral mycosis in 1. Causative fungi for those infections were Candida albicans in 4 patients, Aspergillus, fumigatus in 1 and Aspergillus flavus in 1. The clinical efficacies were excellent in 3 patients and good in 3. The mycological efficacies were rated as eradicated in 5 patients and reduced in 1. In 5 patients to whom FLCZ was given prophylactically, development of neither fungal infection nor unknown fever was noted. No side effects nor clinical laboratory abnormalities were observed during treatment with either granules or injection, indicative of its safety in children.

[Clinical evaluation of aciclovir granules in the treatment of chickenpox in otherwise healthy children]

The efficacy and safety of aciclovir granules (containing 40% w/w aciclovir) were evaluated in the treatment of chickenpox in otherwise healthy children. Patients presenting with chickenpox received aciclovir granules at a dose of 20 mg/kg four times daily for five to seven days. Overall 51 children received treatment with aciclovir. A further 53 patients receiving conventional symptomatic therapy acted as a control. In the aciclovir group the overall efficacy rate was 92.2%. There were reductions in the numbers of lesions, fever, itching and the duration of symptoms. No adverse experiences were reported. Overall this formulation of aciclovir appears to be a safe and effective treatment for chickenpox in this patient population. However the need for anti-viral therapy in otherwise healthy children is still the subject of debate and it might be appropriate to identify sub-groups for whom such therapy is justified.

Gas-phase microsequencing of peptides and proteins with a fluorescent Edman-type reagent, fluorescein isothiocyanate

A fluorescent Edman-type reagent, fluorescein isothiocyanate (FITC), was adapted to a gas-phase sequencer fitted with a miniature reaction chamber. Fluorescein thiohydantion amino acids were identified by on-line gradient HPLC with fluorescence monitoring. The optimized protocol for the coupling reaction using FITC and phenylisothiocyanate, and the degree of washing to remove the excess reagents were established. Myoglobin (5 pmol) and lysozyme (5 pmol) were analyzed by the sequencer to obtain a 35-51% initial yield (I.Y.) and 82-88% repetitive yield (R.Y.) for the former, and 51-66% I.Y. and 91-92% R.Y. for the latter. These figures permitted 20-25 amino acid residues to be identified from the N-terminus of 5 pmol samples applied to the sequencer.

Cytotoxicity against varicella zoster virus infected targets in children with acute leukemia

To eliminate the role of natural killer (NK), antibody-dependent cell-mediated cytotoxicity (ADCC), and polymorphonuclear leukocyte (PMN)-mediated cytotoxicity in Varicella zoster virus (VZV) infections, peripheral blood mononuclear cell (PBMC)-mediated NK and ADCC, and phorbol myristate acetate-stimulated PMN-mediated cytotoxicity against VZV-infected targets were studied in children with leukemia. Natural killer and PMN-mediated cytotoxic activity was depressed for 6 months after complete remission and ADCC activity was depressed for 1 year after complete remission. The magnitude of three cytotoxic mechanisms in leukemic children gradually increased while they continued in complete remission. These results suggested that decreased cytotoxic activities of PBMC and PMN might contribute to serious VZV infections and susceptibility to herpes zoster in leukemic children.

Infection course of the strobilar stage of Taenia crassiceps in golden hamsters, with reference to host responses

The time course of intestinal infection of golden hamsters (Mesocricetus auratus) with Taenia crassiceps was monitored every 2 days up to day 26 postinfection (p.i.). The isolate used was originally obtained from Clethrionomys rutilus on St. Lawrence Island, Bering Sea (USA), and shows a high level of enteral establishment without parenteral infection. Following oral administration of various numbers (3, 15, 30, or 60) of metacestodes, proportional numbers of cestodes attached their scolices to the mucosa of the middle (one-third) segment of the small intestine. Except for animals given 3 metacestodes, dislocation of cestodes to the posterior parts of the intestine was noted on days 10-14 p.i. and began faster in animals that had received larger numbers of metacestodes. Concurrent with dislocation or elimination of cestodes, there existed distinct increases in intestinal eosinophil peroxidase and myeloperoxidase activities. The number of mast cells in the lamina propria peaked on day 16 p.i., and specific serum IgG began to increase within 1 week p.i. The level of all these changes was dose-dependent. In prednisolone-treated animals that received 60 metacestodes, dislocation of cestodes was not evident, and mucosal inflammatory changes were suppressed to a considerable extent. The findings of this study are discussed as a model for the study of canine taeniasis.

A randomized controlled trial of two acellular pertussis-diphtheria-tetanus vaccines in primary immunization in Ghana: antibody responses and adverse reactions

Two acellular pertussis vaccines combined with diphtheria and tetanus toxoids (APDT vaccines) were compared with a whole cell PDT (WCPDT) vaccine in primary immunization in Ghana. One is a liquid vaccine which is used for general immunization in Japan and the other is a freeze-dried vaccine newly developed as a heat-stable vaccine. Eighty-nine infants were recruited in the study. Sixty-eight who completed three doses of the immunization were assessed for immunological responses. Twenty-one dropped out because of sickness or moving from the study area. A total of 242 vaccinations in 89 infants were followed up for adverse reactions. Geometric mean titres (GMTs) to filamentous haemagglutinin in the two APDT vaccinees were significantly higher than in the WCPDT recipients. GMTs to pertussis toxin, diphtheria and tetanus toxoids were not significantly different among the three groups. Seropositive rates to pertussis antigens, tetanus and diphtheria toxoids were 94.4 to 100% in the two APDT vaccines. Systemic reactions within 7 days of inoculation were similarly low in the three groups, but significantly fewer infants had local reactions after either of the two APDT vaccines than after the WCPDT vaccine.

Interferon-gamma induces interleukin-3 release from peripheral blood eosinophils

Interferon-gamma (IFN-gamma) upregulates eosinophil effector functions and prolongs the in vitro survival of eosinophils. We examined the possible capacity of IFN-gamma to stimulate eosinophils to produce eosinophil-activating cytokines. Eosinophils purified from mild atopic volunteers were cultured with 100 U/ml IFN-gamma. Viability of eosinophils was counted and supernatants were tested for the presence of cytokines by neutralization of eosinophil viability-enhancing activity with specific antibodies to IFN-gamma, interleukin-5 (IL-5), IL-3, or granulocyte-macrophage colony-stimulating factor (GM-CSF). IFN-gamma-enhanced eosinophil viability was up to 95% on the 4th day of culture. Pretreatment with anti-IL-3 antibody partially blocked the IFN-gamma-enhanced eosinophil survival. IFN-gamma-stimulated eosinophil supernatants had eosinophil survival. IFN-gamma-stimulated eosinophil supernatants had eosinophil viability-enhancing activity that was blocked by pretreatment not only with anti-IFN-gamma but also with anti-IL-3. Antibodies to IL-5 or GM-CSF did not have the blocking effect. To further confirm the production of IL-3 by eosinophils, we performed reverse transcription polymerase chain reaction (RT-PCR) for IL-3 messenger RNA (mRNA) in IFN-gamma-stimulated eosinophils. Significant IL-3 mRNA expression in eosinophils was observed at 6 h of incubation with IFN-gamma. These results suggest that IFN-gamma stimulates the autocrine function of eosinophils and may play an important role in allergic inflammation.

Inhibition of varicella-zoster virus (VZV) glycoprotein expression by a human monoclonal antibody against VZV glycoprotein III

Effects of human monoclonal antibodies (MAbs) against varicella-zoster virus (VZV) glycoproteins (gp) on VZV glycoprotein expression were analyzed by flow cytometry. Human embryonic fibroblast (HEF) cells were inoculated with cell-free VZV and cultured in the presence of human MAbs. While human MAbs directed against gpI (V2) and -II (V1) did not affect VZV expression, a human MAb against gpIII (V3) inhibited expression of VZV gpI, -II, -III, and -IV. V3 also inhibited spread of VZV from infected to uninfected cells. Interferon-alpha, -beta, and -gamma and tumor necrosis factor-alpha were able to synergize with V3 and inhibit VZV gp expression. These results suggest that human MAb V3 may be useful for passive prophylaxis against VZV infection and for treatment of severe VZV infection.

[Clinical evaluation of S-1108 in children]

We administered S-1108 to 16 children with ages ranging from 7 month to 15 years at doses between 1.8 and 6.0 mg/kg x 3/day for 3 to 13 days. We evaluated the efficacy and safety of S-1108 in 11 children with respiratory tract infections, 3 urinary tract infections, and 2 skin infections. The efficacy rate of S-1108 was 100% and bacteriological eradication rate was 83.3%. No adverse effects were observed. These results suggested that S-1108 could be used safely in children.

Central administration of senktide, a tachykinin NK-3 agonist, has an antidiuretic action by stimulating AVP release in water-loaded rats

Intracerebroventricular (i.c.v.) injections of senktide (0.01-10 nmol), a tachykinin NK-3 agonist, had an antidiuretic action in water-loaded rats (4.5% body wt.). Pretreatment with OPC-31260 (1 mg/kg, i.v.), a non-peptide vasopressin V2 antagonist, inhibited the antidiuretic action induced by exogenous arginine vasopressin (AVP, 0.1 micrograms/kg, i.v.) and senktide (0.1 nmol, i.c.v.). In addition, senktide (11.8 nmol, i.c.v.) caused a marked increase of the plasma AVP level in conscious rats. These results suggest that the central NKB analogue senktide has an antidiuretic effect by stimulating AVP secretion from the pituitary gland through the NK-3 receptor in the hypothalamus.

Inhibition of c-Ha-ras gene expression by hammerhead ribozymes containing a stable C(UUCG)G hairpin loop

Catalytic RNAs recognize specific sequences of RNA and cleave at a specific site. In this study, we designed hammerhead ribozymes with a thermodynamically stable loop of the sequence 5'C(UUCG)G3' to prevent the aggregation of ribozymes with hammerhead structures. The cleavage activities of these ribozymes were examined using a synthetic pentadecamer with the sequence for the c-Ha-ras mRNA mutated at codon 12 (GGU-->GUU). For in vivo studies, we constructed a plasmid which expressed a highly active ribozyme targeted against the mutated c-Ha-ras mRNA. When this ribozyme-encoding gene and the activated c-Ha-ras gene were cotransfected into NIH3T3 cells, morphologically normal cells were obtained. We also determined that the expression of the c-Ha-ras gene was inhibited in these cells. These results show that ribozymes containing this stable hairpin loop are useful for the regulation of specific gene expression in vivo.

Mutation-spectrum of a true abasic site in codon 12 of a c-Ha-ras gene in mammalian cells

An abasic site is postulated to be a premutagenic lesion. We previously reported that a c-Ha-ras gene with an abasic site analogue at either the first or the second position of codon 12 induced the formation of foci by point-mutational activation of the gene [Kamiya et al. (1992) Nucleic Acids Res. 20, 4409-4415]. In this study we constructed c-Ha-ras genes with a true abasic site in codon 12. The ras genes were found to be activated in NIH3T3 cells by a mutation to A at the modified and flanking positions, and the flanking mutations were detected more frequently.

Defect of resistance in male gerbils, Meriones unguiculatus, vaccinated with gamma-irradiated cercariae of Schistosoma mansoni against a homologous challenge infection

Male Mongolian gerbils, Meriones unguiculatus, vaccinated with 500 20-krad gamma-irradiated cercariae of Schistosoma mansoni did not exhibit resistance against a homologous challenge infection. Gerbils appear promising as alternative laboratory hosts for the study of schistosomiasis.

Characterization of peptides in sea anemone venom collected by a novel procedure

Peptide neurotoxins were isolated from the venom obtained by electrical stimulation of the sea anemone Bunodosoma caissarum. This technique allows almost pure venom to be collected, and the animals to survive. Three neurotoxins (assayed on crustacean nerves) were isolated by gel filtration and reversed-phase high performance liquid chromatography. Hemolysins were also detected in the venom. The amino acid sequence of a major neurotoxin BcIII was determined. BcIII has 48 amino acid residues with six half-cystine residues. This sequence has homology with the type 1 long sea anemone neurotoxins. Two minor toxins (BcI and II) have similar amino acid composition and amino-terminal sequences to BcIII.

Acorn barnacle Megabalanus rosa lectin (BRA-3): cDNA cloning, gene structure and seasonal changes of mRNA and protein levels

We have isolated cDNA clones coding for a lectin (BRA-3) from the acorn barnacle, Megabalanus rosa. Sequence comparison of the cDNA clones has revealed polymorphism in the BRA-3 mRNA, which results from single-nucleotide (nt) differences at three positions. All three differences are within the coding region and cause conservative amino acid (aa) changes. The BRA-3 gene is composed of four exons, and the three single-nt differences are located on different exons. In addition, the BRA-3 mRNA and BRA-3 protein levels increased during early summer in a similar fashion, indicating that BRA-3 production is regulated mainly at the level of transcription.

Receptor-mediated specific biological activity of a beta-amyloid protein fragment for NK-1 substance P receptors

A beta-amyloid protein fragment AP21-35 (tetradeapeptide with amino acid residues 21-35) was found to be a highly selective agonist of substance P receptors (NK-1) among three tachykinin receptor subtypes. This peptide fragment contracted the smooth muscle preparations of guinea pig ileum in a dose dependent manner (EC50 = 22 microM). This activity was completely reversed by CP-96,345-1, a specific antagonist of NK-1 receptors, whereas atropine for NK-3 had no effect. The peptide was inactive in rat vas deferens which contains predominantly NK-2 receptors. These results indicated that AP21-35 is a highly selective agonist for NK-1 receptors. In the radio-ligand receptor binding assay using [125I]-Bolton-Hunter substance P to membranes from guinea pig ileum, the fragment exhibited a distinct dose-response curve (IC50 = 11 microM). All the present data strongly suggest that beta-amyloid protein function as a peptide ligand of substance P receptors with some pathophysiologic activities.

Cyclobutane thymine dimers in a ras proto-oncogene hot spot activate the gene by point mutation

ras proto-oncogenes with a cyclobutane-type thymine photodimer (cis-syn or trans-syn isomer) were constructed by replacement of a portion of the gene with a chemically synthesized fragment. When the genes were transfected by the calcium phosphate method into mouse NIH3T3 cells, they induced focus-formation, indicating that both photoproducts were mutagenic in mammalian cells. Sequence analysis of the ras gene fragments derived from the transformed cells showed that the genes were activated by a point mutation. The mutations detected most frequently were 3'-T-->A for the cis-syn isomer and 5'-T-->A for the trans-syn isomer. In contrast, a different trend of mutations was observed when a primer on a DNA template with a cis-syn dimer was extended in vitro by either DNA polymerase beta or alpha.

Pharmacological profiles of muscarinic receptors in the longitudinal smooth muscle of guinea pig ileum

We have examined the pharmacological subtypes of muscarinic receptors mediating phosphoinositide hydrolysis and contraction in the longitudinal smooth muscle of guinea pig ileum with the use of muscarinic antagonists. Carbachol increased the formation of 3H-inositol phosphates (IPs) in a dose-dependent manner in both ileal smooth muscle and the frontal cortex of rats. The rank order of muscarinic antagonists for inhibition of IP formation induced by carbachol was 4-DAMP = atropine > pirenzepine > AF-DX 116 in guinea pig ileal smooth muscle. In ileal smooth muscle, the inhibition by the M1 antagonist pirenzepine was about 15 times less than that by atropine. However, in the rat frontal cortex, the inhibition by pirenzepine was only about 3 times less than that by atropine. The inhibitory effect of the M2 antagonist AF-DX 116 was weak in both ileal muscle and the frontal cortex. The M3 antagonist 4-DAMP strongly inhibited carbachol-induced IP formation in ileal smooth muscle. The rank order of muscarinic antagonists for inhibition of contraction induced by 10(-7) M carbachol was atropine > or = 4-DAMP > pirenzepine > AF-DX 116. These results suggest that both IP formation and the contractile response induced by muscarinic agonists are mediated through the muscarinic M3 subtype in guinea pig ileum.

Increase of interleukin 2 receptor and CD45RO antigen on lymphocytes cultured with human cytomegalovirus

To determine the expression of interleukin 2 receptor (IL-2R) and the change of CD45RA and CD45RO antigen on lymphocytes in response to human cytomegalovirus (HCMV), peripheral blood mononuclear cells (PBMC) were cultured with HCMV antigen, and the expression of IL-2R and of CD45RA and CD45RO antigens on lymphocytes was analyzed by flow cytometry. The expression of IL-2R alpha (p55) and -beta (p75) was significantly increased on T cells obtained from CMV-seropositive donors following culture with the CMV antigen. An increased expression of IL-2R alpha and -beta was observed on both CD4+ and CD8+ cells, but the percentage of cells that expressed IL-2R was higher in CD4+ cells. The percentage of CD45RA+ cells was decreased and the percentage of CD45RO+ cells, especially of CD4+CD45RO+ cells, was increased when cultured with the CMV antigen. These observations suggest that switching of CD45RA+ cells to CD45RO+ cells occurred following stimulation with the CMV antigen. The expression of IL-2R and the activation of memory T cells are important to the recovery from and the protection against CMV infection.

The in vivo and in vitro postantibiotic effect of aminoglycosides using a clinically isolated micro-organism

We reported a case of abscess in which Serratia marcescens was isolated as the causative organism. We measured the postantibiotic effect (PAE) of dibekacin (DKB) and gentamicin (GM) against S. marcescens and studied the relationship between the clinical effect and the PAE. The minimal inhibitory concentration (MIC) of DKB against S. marcescens was 6.25 micrograms/mL and the serum concentration 30 min after infusion of 100 mg DKB was 5.99 micrograms/mL. The abscess was cured by the administration of DKB every 12 h. The PAE in vivo was 2.5, 2.9 and 3.3 h when DKB was administered at 50 mg/kg, 100 mg/kg and 200 mg/kg, respectively. This PAE is one of the reasons that infection can be effectively treated with intermittent administration, even if the serum concentration is below the MIC.