Changes in monoamine turnover in the brain of cachectic mice bearing colon-26 tumor cells

Patients with cancer cachexia often suffer from psychiatric disorders. In the present study, we investigated the changes in monoaminergic activities in the brain in tumor-bearing mice with reference to the development of cachexia. Two clones, clone-5 (noncachectic clone) and clone-20 (cachectic clone), derived from the murine Colon-26 adenocarcinoma cell line (Nippon Roche Research Center), were inoculated subcutaneously at 1 x 10(6) cells/0.2 ml into the right lower back of BALB/c mice. In clone-20 mice, body weight and locomotor activity decreased significantly 10-15 days after tumor inoculation. The levels of noradrenaline, dopamine, and 3,4-dihydroxyphenylacetic acid showed no significant change among the three groups. The noradrenaline turnover rate in clone-20 mice was increased in cerebral cortex, hypothalamus, and midbrain. The 5-hydroxytryptamine turnover rate in clone-20 mice was increased in hippocampus, cerebral cortex, midbrain, and pons-medulla oblongata. In contrast, the dopamine turnover rate in clone-20 mice was decreased markedly in hippocampus, cerebral cortex, striatum, hypothalamus, and cerebellum. There was no significant change in amine turnover between control and clone-5 mice except for dopamine in hippocampus, cerebral cortex, and striatum and 5-hydroxytryptamine in striatum. No significant change in the levels of amino acids in the brain was observed among the three groups of mice. It is concluded that some of the psychiatric disorders from which cancer cachectic patients suffer might be ascribable to changes in monoaminergic activities in the brain.

Potent inhibition of cell density-dependent apoptosis and enhancement of survival by dimethyl sulfoxide in human myeloblastic HL-60 cells

Human myeloblastic cell line HL-60 cells undergo apoptosis during in vitro culture in a cell density-dependent manner, and this cell density-dependent apoptosis was observed when the concentration of cultured cells exceeded 8-10 x 10(5) cells/ml. Dimethyl sulfoxide (DMSO), a differentiation inducer of HL-60 cells, did not amplify, but rather potently inhibited, this apoptosis. In a low density culture condition, DMSO attenuated proliferation of HL-60 cells in spite of its inhibition of apoptosis. In contrast, DMSO did support cell survival under high cell density conditions, and DMSO-treated HL-60 cells reached an extremely high concentration of 2-3 x 10(6) cells/ml, a condition which could never be possible in a usual culture environment. Thus, DMSO exerted dual effects on cell proliferation, i.e., growth inhibition and apoptosis inhibition, and the sum of these effects resulted in an apparently distinct phenomenon according to the culture conditions including cell density.

Identification of spike protein residues of murine coronavirus responsible for receptor-binding activity by use of soluble receptor-resistant mutants

We previously demonstrated by site-directed mutagenesis analysis that the amino acid residues at positions 62 and 214 to 216 in the N-terminal region of mouse hepatitis virus (MHV) spike (S) protein are important for receptor-binding activity (H. Suzuki and F. Taguchi, J. Virol. 70:2632-2636, 1996). To further identify the residues responsible for the activity, we isolated the mutant viruses that were not neutralized with the soluble form of MHV receptor proteins, since such mutants were expected to have mutations in amino acids responsible for receptor-binding activity. Five soluble-receptor-resistant (srr) mutants isolated had mutations in a single amino acid at three different positions: one was at position 65 (Leu to His) (srr11) in the S1 subunit and three were at position 1114 (Leu to Phe) (srr3, srr4, and srr7) and one was at position 1163 (Cys to Phe) (srr18) in the S2 subunit. The receptor-binding activity examined by a virus overlay protein blot assay and by a coimmunoprecipitation assay showed that srr11 S protein had extremely reduced binding activity, while the srr7 and srr18 proteins had binding activity similar to that of wild-type cl-2 protein. However, when cell surface receptors were used for the binding assay, all srr mutants showed activity similar to that of the wild type or only slightly reduced activity. These results, together with our previous observations, suggest that amino acids located at positions 62 to 65 of S1, a region conserved among the MHV strains examined, are important for receptor-binding activity. We also discuss the mechanism by which srr mutants with a mutation in S2 showed high resistance to neutralization by a soluble receptor, despite their sufficient level of binding to soluble receptors.

Developmental capacity of bovine oocytes following inhibition of meiotic resumption by cycloheximide or 6-dimethylaminopurine

This study was conducted to assess the fertilizability and developmental capacity of bovine oocytes which had been maintained in meiotic arrest by either a protein synthesis inhibitor, cycloheximide (CHX), or an inhibitor of serine/threonine protein kinases, 6-dimethylaminopurine (6-DMAP). Both CHX and 6-DMAP reversibly prevented nuclear maturation of nearly all oocytes for 24 h. After the reversal of arrest, CHX-treated oocytes could be successfully matured and fertilized. They developed to the blastocyst stage at slightly lower rates than oocytes cultured without inhibition for 22 h prior to sperm addition but at higher rates than those incubated in a medium containing no inhibitors for 46 h prior to fertilization. Oocytes inhibited by CHX for 48 h matured and fertilized normally but failed to develop into blastocysts. Even though 6-DMAP-treated oocytes completed meiosis I after removal from the drug, the rates of fertilization and blastocyst formation were lower than for untreated oocytes or CHX-treated oocytes. Effects of adding FSH and/or estradiol-17 beta (E(2)) during CHX-inhibition for 24 h were also examined. Embryos from oocytes treated with CHX and E(2) or with CHX and FSH + E(2) developed into blastocysts at similar rates as the controls. Further development of inhibited oocytes was examined by transferring blastocysts derived from oocytes inhibited by CHX with FSH and E(2) for 24 h to recipient heifers. Two calves were obtained following transfer. These results indicate that CHX-inhibited oocytes retain developmental competence, while 6-DMAP-inhibited oocytes after the reversal of arrest have reduced capacities for fertilization and further development. The addition of FSH and E(2) during CHX-inhibition improves development to the blastocyst stage of the oocytes that are capable of initiating and maintaining pregnancy after embryo transfer to recipient animals.

Cell density-dependent apoptosis in HL-60 cells, which is mediated by an unknown soluble factor, is inhibited by transforming growth factor beta1 and overexpression of Bcl-2

We report a novel mode of apoptosis induction observed in human leukemic HL-60 cells. These cells spontaneously underwent apoptosis in the course of proliferation when the cell density became higher than 1 x 10(6)/ml. This occurred under ordinary in vitro culture conditions, with or without fetal calf serum. Even the low density cells were committed to undergo apoptosis if they were cultured under artificially concentrated conditions. Replacement of the culture supernatant of the low density cells by that of the high density ones resulted in apoptosis induction in the former cells. This apoptosis-inducing activity of the high density cell culture supernatant was completely eliminated by the action of trypsin but was fully restored following ultrafiltration by 3-kDa pore-sized membrane. A strong apoptosis-inducing activity was recovered from the culture supernatant of the high density HL-60 cells at a specific fraction in reverse-phase column chromatography. Neither an interleukin-beta converting enzyme inhibitor nor CPP-32 inhibitor blocked the induction of cell density-dependent apoptosis in HL-60 cells, although overexpression of Bcl-2 protein markedly attenuated the induction of this mode. Surprisingly, transforming growth factor-beta1 and activin A did not induce but, rather, inhibited the induction of cell density-dependent apoptosis. These data suggest that HL-60 cells release an unknown low molecular weight peptide-containing factor in response to an increase in cell density to induce apoptosis in an autocrine manner and that the interleukin-beta converting enzyme-independent intracellular machinery for this mode of apoptosis is strongly affected by signaling events through the transforming growth factor-beta1 receptor and by the action of Bcl-2 oncoprotein.

Subglottic stenosis in Wegener's granulomatosis limited to the head and neck region

Subglottic stenosis as a complication of Wegener's granulomatosis (WG) is a relatively rare lesion and is difficult to treat surgically once stenosis becomes sufficiently severe to cause inspiratory dyspnea. Thus, it is important to diagnose WG in its early stages to prevent troublesome subglottic stenosis from developing by initiating immunosuppressive therapy. The authors report on a 30-year-old woman suffering from subglottic stenosis of sudden onset due to protracted WG limited to the head and neck region. She had had exudative otitis media for 13 years and saddle nose and nasal crusting for five years. Repeated biopsies of the nasal mucosa and enzyme-linked immunosorbent assays for cytoplasmic patterns of antineutrophil cytoplasmic autoantibody (cANCA) had failed to establish the diagnosis. However, further histologic examination of the nasal mucosa showed vasculitis, and indirect immunofluorescence detected the presence of cANCA. Thus, the diagnosis of WG was confirmed 13 years after the appearance of the initial symptoms in the ear. The patient was given prednisolone (60 mg/day for five days), which greatly relieved the subglottic stenosis. The prednisolone dosage was then tapered to 5 mg/day.

Differential induction of apoptosis on human lymphoblastic leukemia Nalm-6 and Molt-4 cells by various antitumor drugs

To investigate how chemotherapy agents interact with the leukemic cell death pathway, we examined apoptosis of human lymphoblastic leukemia cells (Nalm-6 and Molt-4) treated with various anticancer drugs (etoposide (VP-16), camptothecin (CPT), adriamycin (ADR), cytosine arabinoside (Ara-C), methotrexate (MTX), 6 mercaptopurine (6MP), cyclophosphamide (CPM), vincristine (VCR) and prednisolone (PRD)) by flow cytometric procedures. The proportion of apoptotic cells was estimated from the presence of cells with a fractional DNA content in the DNA histograms after the incubation of drug-treated cells with a DNA extraction buffer. Treatment with Ara-C, CPT, VP-16 and ADR resulted in rapid apoptosis with 40-60% apoptotic cells by 8 h. Treatment with MTX, VCR, 6MP and PRD induced no apparent apoptosis until 12 h, but further treatments with these drugs resulted in apoptosis with 50% (MTX), 20-30% (6MP and VCR) and 5-10% (PRD) apoptotic cells, respectively, at 24 h. CPM induced apoptosis with 10-20% apoptotic cells at 10(-6) M, but higher doses (> 10(-5) M) caused a rapid cell death by necrosis. The cell cycle position of apoptotic cells was assessed by the terminal deoxynucleotidyl transferase (TdT) assay of DNA strand breaks combined with DNA staining. MTX, Ara-C, CPT, VP-16 and ADR preferentially induced apoptosis in the S phase. PRD and 6MP induced apoptosis in the G1 phase and G1 + S phases, respectively. CPM showed no cell cycle phase specificity. These findings suggested that the susceptibility of cells to apoptosis was not the sole determinant of cellular sensitivity of cytotoxic drugs.

Dual stimulatory and inhibitory effects of fluorine-substitution on mutagenicity: an extension of the enamine epoxide theory for activation of the quinoline nucleus

Nineteen mono- and di-fluorinated derivatives of quinoline, 1,7-phenanthroline, 1,10-phenanthroline, benzo[h]quinoline, and benzo[f]quinoline were subjected to analysis of their structure-mutagenicity relationships. For this purpose, six new fluorinated derivatives were synthesized. The results support that the enamine epoxide structure of the pyridine moiety, as well as the bay-region epoxide structure, is responsible for mutagenicity. Formation of K-region epoxides might involve a detoxification process rather than mutagenic activation.

Immunohistochemical localization of macrophage migration inhibitory factor (MIF) in tanycytes, subcommissural organ and choroid plexus in the rat brain

We investigated the immunohistochemical localization of the macrophage migration inhibitory factor (MIF) in the rat brain. In addition to epithelial ependymal cells lining the ventricular wall, tanycytes in the basomedial hypothalamus were heavily immunostained. The immunoreactive processes of tanycytes made contacts to sinusoidal capillaries and reached the pial surface forming an immuno-positive structure at the floor of the hypothalamus. Other immunoreactive cells contained the subcommissural organ in the roof of the third ventricle and the epithelial lamina of the choroid plexus. The localization of MIF in cells which have contact with cerebrospinal fluid and blood vessels suggests that MIF might play a role as a humoral factor in the brain.

Membrane localization, topology, and mutual stabilization of the rnfABC gene products in Rhodobacter capsulatus and implications for a new family of energy-coupling NADH oxidoreductases

The rnf genes in Rhodobacter capsulatus are unique nitrogen fixation genes that encode potential membrane proteins (RnfA, RnfD, and RnfE) and potential iron-sulfur proteins (RnfB and RnfC). In this study, we first analyzed the localization and topology of the RnfA, RnfB, and RnfC proteins. By activity and immunoblot analysis of expression of translational fusions to Escherichia coli alkaline phosphatase, RnfA protein was shown to span the chromatophore membrane with its odd-numbered hydrophilic regions exposed to periplasm. By alkaline treatment of membrane fractions and following immunoblot analysis using antibodies against recombinant proteins expressed in E. coli, both RnfB and RnfC proteins were revealed to situate at the periphery of the chromatophore membranes. Second, mutual interaction of the Rnf proteins was analyzed by immunochemical determinations of RnfB and RnfC proteins in rnf mutants and their complemented derivatives. The contents in cellular fractions indicated that RnfB and RnfC stabilize each other and that the presence of RnfA is necessary for stable existence of both proteins. These results support a hypothesis that the Rnf products are subunits of a membrane complex. Finally, we detected homologs of rnf genes in Haemophilus influenzae and Vibrio alginolyticus by data base searches and in E. coli by cloning of a fragment of an rnfA homolog followed by a data base search. Close comparisons revealed that RnfC has potential binding sites for NADH and FMN which are similar to those found in proton-translocating NADH:quinone oxidoreductases and that RnfA, RnfD, and RnfE show similarity to subunits of sodium-translocating NADH:quinone oxidoreductases. We predict that the putative Rnf complex represents a novel family of energy-coupling NADH oxidoreductases.

Identification of bradykinin, substance P, and neurokinin A in human dental pulp

Methodology was developed that uses reverse phase, high performance liquid chromatography (HPLC) to identify and quantify bradykinin, substance P, and neurokinin A contained in dental pulp tissue. Pulp tissue was prepared and homogenized from teeth frozen in liquid nitrogen, Known amounts of three substances found in inflamed tissue were added to the homogenized tissue and also to bovine serum albumin (BSA) (positive control), and supernatants were analyzed using HPLC. Other pulp tissue was prepared and analyzed without the addition of the substances. Recovery from the pulp and BSA with added substances was similar, with bradykinin recovered maximally. In pulp tissue without additions, all three substances were recovered. Thus HPLC appears to be a viable alternative to other methods for identification of these substances and allows for their quantification.

cDNA cloning, tissue distribution, and subcellular localization of horseshoe crab big defensin

A full-length cDNA for horseshoe crab big defensin with a strong antimicrobial activity was obtained from a hemocyte cDNA library. The open reading frame of the cDNA coded for an NH2-terminal signal sequence followed by a propeptide and the mature big defensin. The propeptide is linked to the mature protein through an -Arg-X-Lys/Arg-Arg- motif, the processing site for Kex2-like proteases. Northern blot analysis revealed that big defensin is expressed in all the tissues tested, suggesting that big defensin plays an important role not only in hemocytes but also in other tissues for host defense. The subcellular localization, determined by immunocytochemistry at ultrastructural level, confirmed the previous findings obtained by biochemical analysis that big defensin locates in both small and large granules in hemocytes. Big defensin is the first example to demonstrate the existence of broad tissue distribution in horseshoe crab.

Serologic survey for HTLV-I in Kanagawa Prefecture

To investigate the seroprevalence of HTLV-I in Kanagawa Prefecture (central Japan), we tested the sera of 8,264 healthy volunteers and 2,414 pregnant women. Of the 8,264 healthy volunteers, 66 (0.80%) were seropositive. The seroprevalence of HTLV-I in the pregnant women was 14/2,414 (0.58%), and this rate was almost identical to that in the healthy female volunteers 15 to 44 years of age (0.59%). These figures indicate that the seroprevalence of HTLV-I in Kanagawa Prefecture is very low and that sexual contact may not be an important contributory factor.

The seroprevalence of HTLV-I in patients with ocular diseases, pregnant women and healthy volunteers in the Kanto district, central Japan

HTLV-I has been shown to be related to the development of inflammatory diseases in various organs such as the eyes, lungs and joints. In south-west Japan where HTLV-I is highly endemic, the term 'HTLV-I associated complex' has been approved. To investigate the seroprevalence of HTLV-I in the Kanto district in central Japan, we have estimated the frequency of seropositivity to HTLV-I in 2,110 patients with various ocular diseases and 2,683 pregnant women, in addition to 5,336 healthy volunteers. Of the healthy volunteers, only 42 (0.79%) were seropositive, and the HTLV-I seroprevalence in pregnant women was also only 16/2,683 (0.60%) which was almost equal to that in female healthy volunteers aged 15-44 years (0.59%). In patients with various ocular diseases, however, there was significantly higher seroprevalence of HTLV-I (2.32%) compared with healthy volunteers in each sex (male: p = 0.0029; female: p = 0.000023). These results suggest that the seroprevalence of HTLV-I in the Kanto district is much lower than in south-west Japan. On the other hand, HTLV-I infection was shown to be correlated to ocular diseases also in the Kanto district. In particular, we found a higher seroprevalence of HTLV-I in patients with inflammatory ocular disease, such as endogenous uveitis, episcleritis, retinitis pigmentosa and degenerative choroiditis. This possibly suggests a causative role of HTLV-I in the development of these inflammatory ocular diseases also where HTLV-I is not endemic.

Modification of the carcinogenic potency of quinoline, a hepatocarcinogen, by fluorine atom substitution: evaluation of carcinogenicity by a medium-term assay

The potent mutagen, 5-fluoroquinoline (5-FQ), and non-mutagenic 3-fluoroquinoline (3-FQ) were tested for hepatocarcinogenicity using a medium-term assay system employing quinoline, a moderately mutagenic hepatocarcinogen, as a reference. F344 male rats were given a single i.p. injection of a submanifestational dose of diethylnitrosamine (DEN, 200 mg/kg). Then, quinoline, 3-FQ, or 5-FQ at two doses (0.1%, and 0.05%) was added to their diet for a period of 6 weeks, starting from 2 weeks after the DEN injection. Control groups were administered DEN alone. All rats were subjected to a partial (two-thirds) hepatectomy at the end of week 3 and sacrificed at the end of week 8. The number and areas of GST-P (placental glutathione S-transferase)-positive foci induced in the liver increased significantly as a result of treatment with 0.1% quinoline, and this increase was dramatic with 5-FQ at both doses, whereas no increases were noted with 3-FQ at either dose. Thus, the results of the medium-term carcinogenicity assay predicted that quinoline, a hepatocarcinogen, would be deprived of carcinogenicity by fluorine atom substitution at position 3, and would conversely be endowed with a higher carcinogenic capacity by substitution at position 5. A semi-quantitative relationship was demonstrated between carcinogenic and mutagenic potencies.

Site-specific mutagenesis of Rhodobacter capsulatus ferredoxin I, FdxN, that functions in nitrogen fixation. Role of extra residues

One of the two [4Fe-4S]-type clusters of the Rhodobacter capsulatus ferredoxin I, FdxN, was modified through site-specific mutagenesis of the distinctive features of the second cluster-binding motif, Cys38-X2-Cys41-X8-Cys50-X3-Cys54-X4-Cys59. First, various mutagenized products were tested to learn whether they could rescue the decreased capacity of an fdxN-null strain MSA1 to fix nitrogen: the phenotype of MSA1 was reassessed to Nifs (slow growth by nitrogen fixation) from our previous description of Nif- (Saeki, K., Suetsugu, Y., Tokuda, K., Miyatake, Y., Young, D. A., Marrs, B. L. and Matsubara, H. (1991) J. Biol. Chem. 266, 12889-12895). Substitution of Cys59 to Ser yielded an almost fully active product, while that of Cys54 did not. Gradual deletions and deletion-substitution of the 8 residues between Cys41 and Cys50 also yielded active products. Second, three of the modified FdxN proteins were subjected to purification. Only the GA protein, whose 8 residues between positions 42 and 49 were replaced by the Gly-Ala sequence, was purified. The GA protein and the authentic FdxN showed similar optical properties. The two clusters in the former had Em values of -490 and -430 mV, while those in the latter had an identical value of -490 mV, when determined by EPR analysis. It was concluded that: 1) Cys59 is not a ligand to [4Fe-4S] clusters but is important for structural integrity, 2) the residues between positions 42 and 49 may form a "loop-out" from a structure analogous to the Peptococcus aerogenes ferredoxin, and 3) the loop-out region does not have functional significance in nitrogen fixation but may be responsible for maintaining the highly negative redox potential of one of the two clusters.

Cloning of a serine proteinase inhibitor from bovine brain: expression in the brain and characterization of its target proteinases

A cDNA encoding of the serine proteinase inhibitor (serpin), B-43, was cloned from the cDNA library of the bovine brain. It encoded 378 amino acids, and the MW of the protein was estimated to be 42.6 kDa, which is consistent with that of the native B-43 purified from the bovine brain. The homology search revealed that B-43 belongs to the ovalbumin branch of the serpin superfamily. Among them, B-43 was most homologous to human placental thrombin inhibitor (PI-6) and its murine counterpart, with the amino acid identity of 76% and 71%, respectively. Northern blot analysis showed that the size of the transcript was 1.4 kb, and that the expression of B-43 in the bovine brain varied depending on the brain regions, i.e. a lower level of expression was observed in the cerebral cortex and the hippocampus compared to the level of expression that was observed in the medulla oblongata. [35S]-labeled B-43 protein was synthesized in vitro by using a rabbit reticulocyte lysate system, which formed complexes with proteinases such as thrombin, trypsin, alpha-chymotrypsin, and 7S nerve growth factor (NGF), but not with urokinase or plasmin. These results, together with the immunohistochemical localization of B-43 in astrocytes and in some neurons which was observed in the previous study suggest that B-43 may be involved in the regulation of serine proteinases present in the brain or extravasated from the blood.

Tropomyosin-binding site(s) on the Dictyostelium actin surface as identified by site-directed mutagenesis

To identify tropomyosin-binding site(s) on the surface of actin molecule, we examined the effect of mutagenesis introduced to subdomain 4 of actin. Because the sequence of Gln228-Ser232 of Dictyostelium actin differs from that of Tetrahymena actin that does not bind tropomyosin, the Dictyostelium/Tetrahymena chimeric actin was produced. Also, Lys238 and Glu241 were replaced with alanine (mutant 645) to study the role of charged residues which are located at both ends of a beta-sheet. As a control experiment, a negative charge was introduced near to the N-terminus (mutant 663). To facilitate the separation of mutant actins without affecting the normal function, Glu360 was replaced with histidine. As a control mutant to such mutants, the mutant 647 (E360H) was produced. Mutant actins were expressed in Dictyostelium cells. All mutant actins were functional: they (i) polymerize and (ii) activate ATPase activity of rabbit skeletal myosin subfragment-1 (S1). The mutant 663 (G2E) showed tropomyosin binding and activated myosin ATPase almost as well as rabbit skeletal actin. However, the tropomyosin binding of the mutant 645 (K238A/E241A/E360H) became magnesium dependent. The chimeric actin (mutant 646: QTAAS-to-KAYKE replacement and E360H) showed decreased tropomyosin binding even in the presence of magnesium ions. These results indicate that the tropomyosin-binding sites of "on"-state actin are on subdomain 4. Surprisingly, the chimeric actin showed more cooperative calcium regulation than rabbit skeletal actin in the presence of tropomyosin-troponin. The mutant actin 645 can hardly activate S1 ATPase irrespective of calcium concentration in the presence of tropomyosin-troponin, even though this actin by itself can activate S1 ATPase. The steric blocking or cooperative/allosteric mechanism of thin filament regulation is discussed.

Effects of nicotine and exposure to cigarette smoke on suppression of local graft-versus-host reaction induced by immobilization stress in mice

To study the effects of emotional stress on immunological activities and modification of these effects by nicotine or cigarette smoke, we evaluated the effects of immobilization stress on local graft-versus-host (GVH) reaction, a cell-mediated immune response, and the effects of nicotine and cigarette smoke on them. The effects of immobilization stress on GVH reaction and the effects of nicotine and cigarette smoke on them were evaluated in two experiments: in Experiment 1 by applying the stimulations before and immediately after spleen cell transplantation, and in Experiment 2, by applying stimulations after transplantation. Spleen cells of BALB/C mice were injected into the footpad of CBF1 mice, and GVH reaction was examined after 7 days by weighing the popliteal lymph nodes. Immobilization, nicotine administration and inhalation of cigarette smoke were performed either for 5 days before and immediately after the transplantation (Experiment 1) or for 5 days after transplantation (Experiment 2). The weight of the lymph nodes was markedly increased in the control group, indicating GVH reaction, but the reaction was suppressed by immobilization in both experiments. This suppression of GVH reaction by immobilization was antagonized by nicotine administration and exposure to cigarette smoke in Experiment 1 but not in Experiment 2. These findings suggest that nicotine and cigarette smoke induce recovery of immune response suppressed by immobilization stress, especially by increasing the competence of antigen recognition.

Induction of cardiac angiotensinogen mRNA and angiotensin converting enzyme (ACE) activity in isoproterenol-induced heart injury

Effects of isoproterenol (ISO) on the expression of cardiac angiotensinogen mRNA, angiotensin converting enzyme (ACE) activity, and mechanical functions in spontaneously hypertensive rats were investigated. In the acute phase, defined as within 24 h after the subcutaneous injection of ISO 85 mg/kg, cardiac angiotensinogen mRNA was slightly induced, but ACE activity was not. In the subacute phase, defined as within 8 d after ISO treatment on 2 successive d, both angiotensinogen mRNA expression and ACE activity in the heart were markedly induced. ACE activity in serum was not affected by ISO in either phase. In the subacute phase, ISO reduced body weight and blood pressure, increased ventricular weight and calcium content, and impaired cardiac mechanical function. Oral treatment with imidapril (10 mg/kg/d), an ACE inhibitor, 1 h before each ISO treatment and on the following 6 d, improved ventricular hypertrophy, the elevation of the left ventricular end diastolic pressure, the reduction in contractility, and the prolongation of the time constant. Imidapril significantly suppressed both serum and cardiac ACE activity but did not affect cardiac angiotensinogen mRNA expression in the subacute phase. These results indicate that enhancement of cardiac angiotensinogen mRNA and ACE activity is involved in ISO-induced cardiac dysfunction. Imidapril improved ISO-induced cardiac dysfunction, possibly by suppression of the local ACE activity as well as circulating ACE activity.

Presence of macrophage migration inhibitory factor (MIF) in ependyma, astrocytes and neurons in the bovine brain

We investigated the immunohistochemical localization of a cytokine macrophage migration inhibitory factor (MIF) in the bovine brain. MIF was present in the ependymal cell linings of the cerebral ventricles throughout. Double immunostaining of the section with anti-glial fibrillary acidic protein (GFAP) antibody and with anti-MIF antibody showed that the astrocytes present in subependymal layer were immunoreactive for MIF. In the hippocampus, the pyramidal cells in the CA3 and CA4 subfields and the granule cells of the dentate gyrus were immunoreactive. The bundles of mossy fibers were stained along their projections to CA3 and CA4 regions. The nuclei of the subpopulation of these MIF-immunoreactive cells were also immunostained. These results indicated the widespread distribution of a cytokine, MIF, in the bovine brain and suggested the possibility that MIF might play additional roles than a proinflammatory mediator role in the brain.

Intake ratio of water-insoluble dietary fiber to the water-soluble one in Japanese: an estimation on dietary records and the secular consideration on the national nutrition survey

Thirty-four foods were analyzed in order to determine the content of water-soluble dietary fiber (SDF) and insoluble dietary fiber (IDF). Using the results with the standard table for 227 foods, the intake ratio of IDF/SDF of an average Japanese was calculated for the period 1946-1990. The ratio was 3.22 in 1990 as calculated on the food intakes shown in the national nutrition survey, and the secular change was not detected since 1946 when the ratio was 3.30. The ratio was also shown to be well preserved between types of households including the age of the head. Using dietary records of 60 healthy city workers (average 42.8 years) for 4 weeks, however, the weekly average ratio for an individual was found to vary in the range of 2.25-5.13 although the total average for 60 individuals was 3.33. Thus, the well preserved IDF/SDF intake ratio for an average Japanese showed, on the contrary, a wide variation of food selection between each person.

The prevalence of Toxoplasma antibody in patients with various ocular diseases in central Japan

BACKGROUND

Ocular toxoplasmosis has been considered to be a largely asymptomatic infection because of the high seroprevalence of Toxoplasma antibodies and the low rate of clinical diagnosis. On the other hand, Toxoplasma infection has been reported to be associated with the other ocular disease. To investigate the association of Toxoplasma infection with the development of various ocular diseases, we studied Toxoplasma seroprevalence in patients with various ocular diseases.

METHODS

We investigated Toxoplasma seroprevalence in 982 patients with various ocular diseases in central Japan. Then we compared the seroprevalence of anti-Toxoplasma antibodies.

RESULTS

Of 982 patients with various ocular diseases, 122 (12.4%) had serological evidence of previous exposure to Toxoplasma gondii. There were no statistically significant differences among the patients with various ocular diseases. However, the seroprevalence in patients aged 40 to 99 years with macular degenerative lesions was significantly higher than that in patients without these lesions (P < 0.05, Yates' correction).

CONCLUSION

This result suggests that Toxoplasma infection could play some role in the development of a type of macular degenerative lesion.