Prostaglandin E1 induces c-Fos and Myc proteins and protects rat hippocampal cells against hypoxic injury

We investigated the effects of prostaglandin (PG) E1 on the hypoxic injury of fetal rat hippocampal cells. Primary hippocampal cell cultures (embryonic day 18) were established and maintained. After 72 h in culture, PGE1 was added to the serum-free medium at a final concentration of 10(-5)-10(-9) M. Cultures were divided into two groups: The normoxia group was in culture for another 48 h, and the hypoxia group was exposed to 24 h of hypoxia followed by continuation of culture for another 24 h. As a quantitative measure of cell death, lactate dehydrogenase (LDH) activity was estimated in the culture medium. The LDH activity, released by the hypoxic insult, was significantly smaller with PGE1 treatment at 10(-6), 10(-7), and 10(-8) M (p < 0.01) and 10(-9) M (p < 0.05) compared with the control. No differences in the LDH activities were observed in the normoxia group. Glial culture was not affected by the hypoxia. Western blot analysis showed an increased induction of 62-kDa c-Fos and 58, 60, and 66 kDa Myc proteins in rat hippocampal cells with 10(-7) M PGE1 treatment. We conclude that PGE1 at concentrations of 10(-6)-10(-9) M protects rat hippocampal neurons against hypoxic insult.

Participation of ouabainlike compound in reduced renal mass-saline hypertension

We examined the role of ouabainlike compound in reduced renal mass-saline hypertension using a population of rats immunized with ouabain. To develop ouabain-immunized rats, ouabain-bovine serum albumin conjugates were injected subcutaneously three times at 4-week intervals. Titer determinations were made 2 weeks after the third immunization, and rats with high titers were used in the study. Immunoglobulin G fractions from ouabain-immunized rats effectively inhibited the contractile response of guinea pig aorta to exogenous ouabain (150 nmol). Fourteen ouabain-immunized and seven nonimmunized control rats underwent subtotal nephrectomy. An additional eight ouabain-immunized and six nonimmunized rats served as sham-operated rats. Four groups of rats drank 1% NaCl solution for 3 weeks, and systolic blood pressure was measured weekly by the tail-cuff method. Two groups of sham-operated rats remained normotensive. In contrast, two groups of subtotally nephrectomized rats developed hypertension. However, among these rats, systolic blood pressure was significantly lower in ouabain-immunized rats than in nonimmunized rats (161 +/- 5 versus 180 +/- 3 [+/- SEM) mm Hg, P < .01). The decrease in blood pressure was accompanied by a significant inhibition of aortic hypertrophy (P < .05). These results indicate that chronic blockade of circulating ouabainlike compound partly ameliorates reduced renal mass-saline hypertension and suggest that circulating ouabainlike compound may be involved in the pathophysiology in this model of hypertension.

Relationship between anti-aversive effects of salmon calcitonin and plasma levels of ACTH, beta-endorphin and prostaglandin E2 in mice

We investigated whether the anti-aversive effects of salmon calcitonin (SCT) was induced by increasing ACTH and beta-endorphin and/or by decreasing of prostaglandin E2 (PGE2) levels in plasma of mice to elucidate the mechanisms responsible for the analgesic effects of SCT. Intracerebroventricular (i.c.v.) injections of SCT inhibited acetic acid-induced aversive behavior (writhing) in a U-shaped dose response curve, the most effective dose being 0.1 IU/mouse. Intraperitoneal (i.p.) injections of acetic acid increased, but not significantly, the levels of plasma ACTH and PGE2, but not beta-endorphin, which are considered to be psychoneuroendocrines correlated with pain. SCT (0.1 IU/mouse, i.c.v.) significantly increased plasma ACTH levels (p < 0.05) and tended to increase beta-endorphin levels (p = 0.052) in acetic acid-treated mice, whereas no change in PGE2 level was observed (p > 0.1). These results suggest that the anti-aversive effects of SCT may be mediated, at least in part, by the activation of ACTH.

Effect of a single injection of psychoactive drugs on CCK mRNA in rat brain

The acute and long-term effects of a single injection of psychoactive drugs, methamphetamine or phencyclidine, were investigated by Northern blot to assess alterations in the cholecystokinin (CCK) mRNA in three areas of the rat brain. In the frontal cortex, there were no significant changes in CCK mRNA after the drug injection. In contrast, decreases in CCK mRNA were observed in the posterior cortex and the hippocampus from 30 min to 48 h after the drug treatment. The data suggest that CCK gene expression has different sensitivity to these psychoactive drugs within the cortices.

An expectorant, stepronin, reduces airway secretion in vitro

Stepronin (SPN) is clinically used as an expectorant, and thenoic acid (TA) is its metabolite. We examined the effects of these drugs on the bioelectric parameters [potential difference (PD), short circuit current (SCC), conductance (G)] of the posterior epithelial membrane of canine trachea and on those of the mucus glycoprotein secretion from feline tracheal isolated glands. PD and SCC were obtained using an Ussing chamber and G was calculated as the ratio SCC/PD. Neither SPN nor TA significantly altered the baseline values of PD and SCC. However, in the mucosal solution, both SPN and TA significantly inhibited PD and SCC evoked by isoproterenol (ISOP), whereas G remained unchanged. Amirolide did not alter the inhibitory action of SPN and TA. Mucus glycoprotein secretion from isolated glands was estimated by measuring trichloride acetic acid-precipitable [3H]-glycoconjugates. SPN and TA significantly reduced mucus glycoprotein secretion. Further, when stimulated by methacholine, these agents significantly inhibited mucus glycoprotein secretion from isolated glands. These findings suggest that SPN inhibits airway secretion in vitro by both decreasing Cl- secretion from epithelial cells and mucus glycoprotein secretion from submucosal glands.

Ethylene vinylacetate copolymer particles dissolved in polyvinyl alcohol (2,000-mer) solution as an embolic material for vascular anomalies. A preliminary study

We have prepared a new material for embolisation: ethylene vinylacetate copolymer dissolved in polyvinyl alcohol. When in contact with blood, polyvinyl alcohol rapidly becomes a soft gel, which is accompanied by wedging of the ethylene vinylacetate copolymer. We analysed the histopathology of intra-arterial microemboli in rats, after intracarotid injection of this material. We confirmed that it was applicable to embolisation for neurosurgical treatment.

The initial contraction of skinned muscle fibers on photorelease of ATP in the presence of ADP

1) We photoreleased ATP in skinned muscle fibers from rat psoas, and examined the effects of ADP on the ATP-induced isometric transient. 2) On release of ATP, the muscle stiffness initially falls at any [Ca2+]. ADP slowed this stiffness decrease, suggesting competition between ADP and ATP. Even in the presence of ADP, the rate of stiffness decrease was proportional to the amount of released ATP, but was not affected by Ca2+, P(i), or the fiber tension. 3) In the absence of ADP, the Ca2+ sensitive contraction occurs only after the initial phase. However, in the presence of ADP, the fiber developed tension during the initial phase before the late contraction. The initial contraction was insensitive to Ca2+, resistant to P(i) and BDM, larger on releasing more ATP, but not markedly influenced by the fiber tension. 4) Our results seem to suggest that, in the physiological reaction cycle, the cross-bridges develop significant force immediately after the binding of ATP, before releasing P(i).

Blood-borne macromolecule induces FGF receptor gene expression after focal ischemia

We have detected fibroblast growth factor receptor (FGFR) gene expression in the focal ischemia model. The FGFR gene expression in neurons can be explained by neuronal network disturbances, but the mechanism of astroglial gene expression remains uncertain. We speculated that blood-borne edema fluid may activate gene expression of astroglias. To prove this hypothesis, we compared the pattern's of gene expression of FGFR and distribution of edema fluid by using serial tissue sections of the middle cerebral artery (MCA) ischemia. The left MCA of twenty-four male Wistar rats were occluded, and sacrificed 1, 3, 4, 7 and 14 days later by transcardiac perfusion and fixation. The tissues were sliced thinly to 14 microns sections. Part of the tissue sections was used for in situ hybridization for rat FGFR with [35S]labeled RNA probes. The other part of the sections was used for immunostaining for albumin, immunoglobulin G (IgG) and IgM. The FGFR mRNA expression was evident in the lesion-side hemisphere. In the cortex, neurons mainly expressed FGFR gene in the cortex, whereas astroglias and capillary endothelium expressed FGFR in the corpus callosum and internal capsule. The albumin distributed cortex and white matter of the lesion-side and it extended to the contralateral side. The IgG distributed mainly in the lesion-side white matter, and in part extended to the contralateral side. The IgM only distribute to the infarcted area. When we compared topographical distribution of FGFR in the white matter and pattern of albumin, IgG and IgM distribution, pattern of IgG distribution correlated well to the area of FGFR expression.(ABSTRACT TRUNCATED AT 250 WORDS)

31P magnetic resonance spectroscopy of the medial temporal lobe of schizophrenic patients with neuroleptic-resistant marked positive symptoms

31P magnetic resonance spectroscopy was performed in 16 mediated schizophrenic patients with neuroleptic-resistant marked positive symptoms and in 16 healthy volunteers matched for age and sex in order to determine what changes in phosphorus metabolites are detected in such patients as compared to the controls. The schizophrenic patients showed an increased level of phosphodiesters in the bilateral medial temporal lobes. They also showed a decrease in the level of beta-ATP in the left medial temporal lobe. These findings suggest that schizophrenic patients with prominent positive symptoms refractory to neuroleptics may have a disturbance of bilateral membrane phospholipid and left-sided high-energy phosphate metabolism in the medial temporal lobe.

[Treatment of promyelocytic blast crisis of chronic myelogenous leukemia with all-trans-retinoic acid]

This paper describes the treatment of promyelocytic blast crisis of chronic myelogenous leukemia with all-trans-retinoic acid (ATRA). The patient, a 22-year-old male, was diagnosed to have APL and had been treated with busulfan and then with three and half years interferon (IFN) alpha in the chronic phase. A cytogenetic study of blast cells showed the t(1;17) (p11;q11) translocation as the second chromosomal abnormality without morphological abnormality of chromosome 15. Molecular analysis showed cells to have a chimera gene consisted of PML and retinoic acid receptor alpha genes. Though maturation and differentiation of leukemic cells were seen after ATRA therapy, hematological complete remission did not occur. The ineffectiveness of ATRA may be dut to different pathological conditions from de novo APL, or progressive reduction in plasma ATRA concentration as reported by Muindi et al. When our case was compared with a similar case reported by Wiernick et al., both cases were treated with IFN alpha in the chronic phases, had no t(15;17) translocation involving No.1 chromosome abnormality and did not develop complete remission after ATRA therapy.

Expression of basic fibroblast growth factor receptor messenger RNA in the periinfarcted brain tissue

The present study examined whether expression of basic fibroblast growth factor receptor (bFGFR) messenger ribonucleic acid (mRNA) was upregulated by focal ischemia. We have studied the in situ hybridization autoradiography for bFGFR mRNA in the rat model of middle cerebral artery (MCA) occlusion. Male Wistar rats were used for occlusion of the left MCA, and were sacrificed 1, 3, 7 and 14 days after MCA occlusion. In situ hybridization was performed on the brain sections of these animals and sham controls by using 35S-labeled antisense and sense (control) RNA probes for rat bFGFR. Expression of bFGFR mRNA was observed in the periinfarcted area of the rats within 1-14 days after MCA occlusion. Expression was evident in the whole hemisphere of the infarcted side, especially at 1 and 3 days after ischemia, but no expression was detected in the contralateral side. On microautoradiograms, the signals of bFGFR mRNA were detected in both neurons and non-neural cells located in the periinfarcted area. Upregulation of bFGFR mRNA detected in the periinfarcted brain tissue suggests that receptor-mediated action of bFGF may be related to preservation of neurons injured by ischemia.

Cloning, sequence and characterization of the polyphosphate kinase-encoding gene (ppk) of Klebsiella aerogenes

Polyphosphate kinase (PPK) catalyzes the formation of polyphosphate (polyP). The PPK-encoding gene (ppk) has been cloned from Klebsiella aerogenes ATCC9621. The gene possessed an open reading frame of 2055 bp capable of encoding a putative polypeptide with a deduced M(r) of 80,157. This polypeptide showed 93% similarity to the Escherichia coli PPK. The nucleotide sequence of the promoter region of K. aerogenes ppk differed from that of the previously sequenced E. coli ppk. A putative pho box sequence was found in the promoter region of K. aerogenes ppk. The expression of lacZ from the ppk promoter was increased in E. coli MV1184 under conditions of phosphate (Pi) limitation, but not in E. coli ANCS3 (phoB-), indicating that the ppk promoter is regulated by the phoB product. Increased levels of specific PPK activity were shown by expressing the cloned ppk at high levels, resulting in increased accumulation of polyP in E. coli.

[A case of marked eosinophilia in peripheral blood induced by rhGM-CSF]

A 53-year-old man underwent chemotherapy (CDDP, VDS, MMC) for treatment of lung cancer. He was given 125 micrograms/m2 of GM-CSF subcutaneously every day for 8 consecutive days, in order to prevent neutropenia. Three days after starting GM-CSF therapy, marked eosinophilia in peripheral blood was observed. The maximum eosinophil count was 89% of leukocytes. Nine days after stopping the treatment with GM-CSF, the number of eosinophils had normalized spontaneously. There were no clinical symptoms except for slight fever, up to 37.5 degrees C. Moreover, there was no relationship between the number of eosinophils and the serum levels of cytokines (IL-3, IL-5, GM-CSF), although we observed minimal but significant elevation of serum ECP level. This case indicates that GM-CSF may induce marked eosinophilia rather than widely stimulating granulocytes and monocytes.

Reproduction of progressive retinal degeneration (bright blindness) in sheep by administration of ptaquiloside contained in bracken

The process of occurrence of bright blindness, progressive retinal degeneration (PRD), in sheep was observed using two Suffolk ram lambs fed on a diet containing bracken powder. The first sign of the bright blindness was detected 4 months after the start of experiment. Based on these preliminary results, the amount of bracken powder necessary to induce PRD was estimated (experiment I). In the following experiment, ptaquiloside (PT), a norsesquiterpene glucoside of the illudane type isolated from bracken, which is a bracken carcinogen and a causative principle of cattle bracken poisoning was administered to two Suffolk ram lambs. It was clearly demonstrated in this experiment (experiment II) that PT present in bracken is also a causative principle of PRD.

IGF-II producing hepatic fibrosarcoma associated with hypoglycemia

A 67-year-old male was admitted with the complaint of weakness at hunger early in the morning, when blood glucose was less than 40 mg/dl. The abdominal ultrasonogram and computerized tomogram demonstrated a huge tumor in the right liver lobe. Hypoglycemia disappeared after transcatheter arterial embolization. Then hepatic lobectomy was performed. The tumor was histologically shown to be a fibrosarcoma. Insulin-like growth factor-II was intensely stained in the Golgi area of the tumor cells, suggesting its role in the mechanism of hypoglycemia.

Kinetics and mechanism of heterogeneous hydrolysis of poly[(R)-3-hydroxybutyrate] film by PHA depolymerases

The kinetics and mechanism of enzymatic degradation on the surface of poly[(R)-3-hydroxybutyrate] (P[(R)-3HB]) film have been studied using three types of extracellular poly(hydroxyalkanoate) (PHA) depolymerases from Alcaligenes faecalis, Pseudomonas picketti and Comamonas testosteroni. The monomer and dimer of 3-hydroxybutyric acid were produced during the course of the enzymatic degradation of P[(R)-3HB] film, and the rate of production was determined by monitoring the increase in absorbance at 210 nm on a spectrophotometer. The rate of enzymatic degradation increased to a maximum value with the concentration of PHA depolymerase, followed by a gradual decrease. The kinetic data were accounted for in terms of a heterogeneous enzymatic reaction, involving enzymatic degradation on the surface of P[(R)-3HB] film via two steps of adsorption and hydrolysis by a PHA depolymerase with binding and catalytic domains. The kinetic results suggest that the properties of the catalytic domains are very similar among the three PHA depolymerases, but that those of the binding domains are strongly dependent on the type of depolymerase.

Neuropharmacological characterization of voltage-sensitive calcium channels: possible existence of neomycin-sensitive, omega-conotoxin GVIA- and dihydropyridines-resistant calcium channels in the rat brain

We attempted to characterize the functional roles of subtypes of voltage-sensitive calcium channels in the brain. The maximal number of [125I]omega-conotoxin GVIA (omega-CTX) binding sites in rat brain associated with N-type calcium channels (N-channels) was approximately 10 times more than that of [3H]-PN200-110 associated with L-type calcium channels (L-channels). [125I]omega-CTX binding was inhibited by aminoglycoside antibiotics, neomycin and dynorphin A(1-13), but not by various classes of L-channel antagonists. A 6-hydroxydopamine-induced lesion of the striatum resulted in a marked reduction of both [125I]-omega-CTX and [3H]PN200-110 binding. Kainic acid-induced lesion of the striatum reduced [3H]PN200-110 binding by 57%, but did not reduce [125I]omega-CTX binding. Omega-CTX produced a small (18%) but significant reduction of potassium-stimulated Ca2+ influx into rat brain synaptosomes, although it produced a concentration-dependent inhibition in chick brain synaptosomes. Neomycin inhibited Ca2+ influx in both preparations in a concentration-dependent manner. Both omega-CTX and neomycin inhibited potassium-stimulated [3H]dopamine (DA) release from rat striatal slices. The L-channel antagonists had no effect on either Ca2+ influx or [3H]DA release. These results suggest that DA release in the striatum is regulated by Ca2+ influx through N-channels located in presynaptic nerve terminals, and that the most of the Ca2+ influx in rat brain appears to be governed by neomycin-sensitive, omega-CTX- and DHP-resistant calcium channels.

[Pathogenesis of idiopathic pulmonary fibrosis--is hepatitis C virus involved?]

Hepatitis C virus (HCV) is a new virus discovered in 1989. Since HCV is known to cause fibrotic changes in the liver, we studied whether HCV is involved in the pathogenesis of idiopathic pulmonary fibrosis (IPF). Firstly, we assessed anti-HCV antibodies by enzyme-linked immunosorbent assay (ELISA) in the sera obtained from 66 IPF patients (46 males and 20 females; mean age +/- SEM, 61.5 +/- 10.1). We observed a significantly high prevalence of anti-HCV antibodies in IPF compared with 9,464 age-matched controls (28.8% vs 3.66%, p < 0.05). To confirm the results, recombinant immunoblotting assay (RIBA) was conducted on the 19 ELISA-positive sera, and 8 sera (12.2%) were found to be definitely positive. Secondly, we searched for HCV in the blood of IPF patients by reverse transcription-polymerase chain reaction. As preliminary data, four out of 28 cases (14.3%), all of which were pathologically diagnosed as UIP, were positive for HCV. In conclusion, although further investigation is required, a high prevalence of anti-HCV antibodies and the existence of HCV itself in the blood may suggest the possibility that HCV infection plays an important role in the pathogenesis of IPF.

[Detection of HIV-1 proviral DNA in peripheral leukocytes by AMPLICOR HIV-1 test kit]

AMPLICOR HIV-1 test kits, which had been developed as an HIV-1 provirus detection test by PCR method, have been evaluated for its clinical diagnostic application. Sixty-six of HIV-1 antibody positive and 67 of HIV-1 antibody negative blood samples derived from hemophiliacs, who had received blood products, have been tested by AMPLICOR HIV-1. All of the results from AMPLICOR HIV-1 were consistent with those from antibody test and clinical aspects. Thirty-nine of HIV-1 antibody positive samples have been tested by AMPLICOR HIV-1 and virus isolation (culture method). Twelve of 39 (30.8%) were positive by virus isolation, and 39 of 39 (100%) were positive by AMPLICOR HIV-1. Two of new born infants from HIV-1 sero-positive mothers were tested by AMPLICOR HIV-1, and the result suggested that the kit would be useful for diagnosis of infants from sero-positive mothers. Based on these studies, AMPLICOR HIV-1 is considered as useful clinical diagnostic for HIV-1 proviral DNA detection.

Evaluation of masked neurological disorders in the chronic stage after middle cerebral artery occlusion in rats--methamphetamine-induced rotation and regional glucose metabolism in basal ganglia

Neurofunctional changes in rats in the chronic stage of focal cerebral ischemia induced by left middle cerebral artery (MCA) occlusion were examined. Neurological disorders and behavioral changes were observed with or without methamphetamine administration. Metabolic changes in the basal ganglia following methamphetamine intraperitoneal injection were evaluated by [14C]deoxyglucose autoradiography 30 days after occlusion. Neurological examination revealed persistent spontaneous rotation to the lesioned side in two of 18 rats, and forelimb flexion to the lesioned side in nine of 18 rats during a 28-day observation period after occlusion. Intraperitoneal administration of methamphetamine (4 mg/kg) induced full 360 degrees rotation toward the lesion side in 14 of 17 rats. The number of rotations was inversely correlated with the size of the intact striatum on the lesion side, especially in rats with cerebral infarct located only in the striatum. Rats with extensive cortical lesion in addition to striatal lesion did not demonstrate this relationship. Deoxyglucose autoradiography in methamphetamine-untreated rats showed symmetrical local cerebral glucose utilization in the basal ganglia except for the subthalamic nucleus, striatum and sensorimotor cortex. Autoradiography in methamphetamine-treated and MCA-occluded rats showed a remarkable increase in glucose utilization in the anterior striatum, entopeduncular nucleus, substantia nigra pars reticulata, and sensorimotor cortex contralateral to the occlusion side, but not on the lesioned side. Rotational movements observed in methamphetamine-treated rats are related to lack of stimulation of the basal ganglia system on the ischemic side.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of severe localized cerebral vasospasm following recurrent hemorrhage from middle cerebral artery aneurysm--case report

A 52-year-old female presented with localized but severe cerebral vasospasm induced by recurrent aneurysmal subarachnoid hemorrhage. The middle cerebral artery (MCA) aneurysm was clipped and the subarachnoid hematoma evacuated 1 day after recurrent hemorrhage. The cerebral vasospasm, localized in a region near the MCA aneurysm, was reduced by papaverine and nicardipine vasodilating agents delivered via an Ommaya cerebrospinal fluid reservoir placed at craniotomy.

Effect of an ultraviolet light-activated coating material on reduction of the leaching of methyl methacrylate and formaldehyde from denture acrylic resins

Effect of glazing with an ultraviolet light-activated coating material on reduction of the leaching of methyl methacrylate and formaldehyde from denture acrylic resins was quantitatively evaluated. Disks prepared from auto-polymerized resins were painted with the material and radiated with ultraviolet light. The disks were immersed in artificial saliva and the concentrations of methyl methacrylate and formaldehyde leached were determined by high-performance liquid chromatography and flow injection analysis. Compared to untreated controls, the glaze significantly decreased concentrations of both leachable substances. Treatment with an ultraviolet light-activated coating material is effective in suppressing the leaching of methyl methacrylate and formaldehyde from acrylic resins as well as in smoothing the denture surfaces.

Nitric oxide and nitric oxide synthase mRNA induction in mouse islet cells by interferon-gamma plus tumor necrosis factor-alpha

It has been shown that nitric oxide (NO) is involved in islet cell damage induced by interleukin-1 (IL-1). Here we show that interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) synergistically induced NO production and inducible NO synthase (iNOS) mRNA expression in mouse islet cells. Cycloheximide (CXH) did not prevent the iNOS mRNA expressions. The combination of IFN-gamma and TNF-alpha, which is highly cytotoxic to mouse islet cells, failed to destruct islet cells in the absence of L-arginine or in the presence of NG-monomethyl-L-arginine (NMMA). These observations suggest that NO is a primary effector in islet cell damage caused by IFN-gamma plus TNF-alpha.