Effects of an AT1 receptor antagonist, an ACE inhibitor and a calcium channel antagonist on cardiac gene expressions in hypertensive rats

1. This study was undertaken to determine whether the AT1 receptor directly contributes to hypertension-induced cardiac hypertrophy and gene expressions. 2. Stroke-prone spontaneously hypertensive rats (SHRSP) were given orally an AT1, receptor antagonist (losartan, 30 mg kg-1 day-1), an angiotensin converting enzyme inhibitor (enalapril 10 mg kg-1 day-1), a dihydropyridine calcium channel antagonist (amlodipine, 5 mg kg-1 day-1), or vehicle (control), for 8 weeks (from 16 to 24 weeks of age). The effects of each drug were compared on ventricular weight and mRNA levels for myocardial phenotype- and fibrosis-related genes. 3. Left ventricular hypertrophy of SHRSP was accompanied by the increase in mRNA levels for two foetal phenotypes of contractile proteins (skeletal alpha-actin and beta-myosin heavy chain (beta-MHC)), atrial natriuretic polypeptide (ANP), transforming growth factor-beta-1 (TGF-beta 1) and collagen, and a decrease in mRNA levels for an adult phenotype of contractile protein (alpha-MHC). Thus, the left ventricle of SHRSP was characterized by myocardial transition from an adult to a foetal phenotype and interstitial fibrosis at the molecular level. 4. Although losartan, enalapril and amlodipine lowered blood pressure of SHRSP to a comparable degree throughout the treatment, losartan caused regression of left ventricular hypertrophy of SHRSP to a greater extent than amlodipine (P < 0.01). 5. Losartan significantly decreased mRNA levels for skeletal alpha-actin, ANP, TGF-beta 1 and collagen types I, III and IV and increased alpha-MHC mRNA in the left ventricle of SHRSP. Amlodipine did not alter left ventricular ANP, alpha-MHC and collagen types I and IV mRNA levels of SHRSP. 6. The effects of enalapril on left ventricular hypertrophy and gene expressions of SHRSP were similar to those of losartan, except for the lack of inhibition of collagen type I expression by enalapril. 7. Unlike the hypertrophied left ventricle, there was no significant difference between losartan and amlodipine in the effects on non-hypertrophied right ventricular gene expressions of SHRSP. 8. Our results show that hypertension causes not only left ventricular hypertrophy but also molecular transition of myocardium to a foetal phenotype and interstitial fibrosis-related molecular changes. These hypertension-induced left ventricular molecular changes may be at least in part mediated by the direct action of local angiotensin II via the AT1, receptor.

Derivation of the aerosol size distribution from a bistatic system of a muitiwavelength laser with the singular value decomposition method

Estimation of aerosol size distributions from measurements of scattered light intensity by the use of a bistatic system with a multiwavelength laser is presented. We investigated the effects of inversion of the scattered intensity on calculated aerosol size distribution in a numerical experiment. Two model aerosol size distributions were used, one a Junge type widely known as a typical example of the size distribution of suspended particles in the atmosphere and the other a log-normal type as an example of the monodisperse distribution. A singular value decomposition was applied to the inversion to infer the size distribution from the kernel function and the scattered light intensity. In the physical experiment, the size distributions were successfully inferred from analysis of the scattered light intensity from an artificial polystyrene latex aerosol.

Endo.SK1: an inducible site-specific endonuclease from yeast mitochondria

Site-specific endonucleases have been found in various eukaryotic organelles such as mitochondria, chloroplasts and nuclei. These endonucleases initiate site-specific or homologous gene conversion in mitochondrial and nuclear DNA. Here, we report a new site-specific endonuclease activity, Endo.SK1, identified in mitochondria of strain SK1, a homothallic diploid strain of Saccharomyces cerevisiae. Nucleotide sequences around the Endo.SK1-cleavage sites are different from those of known yeast site-specific endonucleases. The Endo.SK1 activity is, at least partly, specified by a gene in the SK1-derived mitochondria. A novel feature of the Endo.SK1 activity is its inducibility: the endonuclease activity was induced by ca. 40-fold by transfer of cells from a glucose medium into an acetate medium, and was then repressed. This transient induction was independent of the ploidy level of the cells, and coincided with induction of fumarase, a mitochondrial enzyme involved in the TCA cycle. Co-induction and co-repression of the mitochondrial site-specific endonuclease activity and a respiration-related enzyme indicate that the endonuclease activity in regulated in response to physiological conditions, and suggest a possible role for the endonuclease in mitochondrial DNA metabolism.

Apoptosis-related fas antigen on memory T cells in aqueous humor of uveitis patients

To investigate the role of lymphocytes in the pathogenesis of uveitis, we analyzed the expression of memory markers, CD29 and CD45RO antigens, and apoptosis-related Fas antigen on T lymphocytes in the aqueous humor (AH) and peripheral blood (PB) from patients with uveitis. Using three-color flow cytometry, we assessed the number of T lymphocyte subsets that stained with fluorescence-conjugated anti-CD3, CD4, CD8, CD29, CD45RA, CD45RO, HLA-DR, and Fas monoclonal antibodies in the AH and PB from 19 patients with active uveitis who were diagnosed as having sarcoidosis, Vogt-Koyanagi-Harada disease, HLA-B27+ uveitis, or idiopathic uveitis. Cells from AH and PB were evaluated by light and electron microscopy before and after 6 h of incubation. The majority of lymphocytes in AH but not in PB, were CD3+HLA-DR+ (activated) T cells. The percentage of CD4+ lymphocytes was significantly higher in uveitic AH than in PBL (P < 0.01). While the percentage of CD4+ CD45RA+ (naive) cells within T cells was much lower in uveitic AH than in PB, the percentage of CD4+CD29+ or CD4+CD45RO+ (memory) cells was significantly higher in uveitic AH than in PBL (P < 0.01). Fas antigen was expressed preferentially on memory cells in uveitic AH. Apoptosis of cells in the AH was observed by microscopically following after incubation with no stimulation. Lymphocytes from the AH of patients with uveitis were more activated than those from PB. The majority of T lymphocytes from uveitic AH expressed memory markers and Fas antigen. Results suggest that an increase in the number of Fas+ memory T lymphocytes in AH is involved in the pathogenesis of uveitis.

Regional specification of motoneurons along the anterior-posterior axis is independent of the notochord

Cek8 and low affinity NGF receptor (LNGFR) are expressed at high levels on the chick spinal motoneurons of the brachial and lumbar segments from embryonic day (E) 5 to E7, but weakly on the motoneurons of the non-limb-innervating segments. We determined by means of heterotopic neural tube transplantation, that the expression of these molecules was already intrinsically determined at E2. We used these spatiotemporal specific molecules as markers of motoneuron subpopulations. To analyze how motoneurons acquire regional specification along the anterior-posterior (A-P) axis and in the transverse plane, we observed the expression of these molecules on ectopic motoneurons induced by implanting a supernumerary notochord or floor plate at E2. The ectopic motoneurons induced by the graft obtained from either the thoracic or lumbar segments had the same expression profile as the normal motoneurons at each A-P level. These findings suggest that regional specification of motoneurons, at least of Cek8 and LNGFR expression, is independent of the notochord and the floor plate and that the whole neural tube appears to be committed to differentiate into the motoneuron subtypes along the A-P axis at the operative stages.

Nucleotide sequence of a cDNA coding for cyclophilin of the sea urchin Hemicentrotus pulcherrimus

We present the nucleotide sequence of a cDNA coding for cyclophilin homologue of the sea urchin Hemicentrotus pulcherrimus. The 1,755-nucleotide sequence contains a 492-bp open reading frame corresponding to a translation product of 164 amino acids. Comparison of the deduced amino acid sequence with the previous data shows a high degree of conservation (approximately 80% homology). Southern blot analysis of genomic DNA suggests the presence of a multigene for sea urchin cyclophilin. Northern blot analysis indicates a mRNA size of approximately 3 kb and that message is accumulated at blastula stage.

Deletion mapping on chromosome 1p in well-differentiated gastric cancer

To define the region on the short arm of chromosome 1 that is thought to include one or more tumour-suppressor genes for gastric cancers, we carried out loss of heterozygosity (LOH) studies in 26 gastric adenocarcinomas, using three restriction fragment length polymorphism (RFLP) markers and nine microsatellite markers. All tumours were informative with at least one locus; three revealed replication errors (RERs) at multiple microsatellite loci, and interstitial or telomeric allelic deletions were observed in 12 cases. Deletion mapping of these tumours defined a commonly deleted region between two loci, D1S201 and D1S197, that are 13 cM apart. As two loci within the commonly deleted region, D1S57 (pYNZ2) and D1S62 (pTHI54), were mapped respectively to 1p35 and 1p34.3 by fluorescence in situ hybridisation, we conclude that a locus likely to contain a tumour-suppressor gene for gastric cancer is located within a 13 cM region encompassing two chromosomal bands.

Evaluation of sialyl Lewisx antigen in the skin and the sera of patients with psoriasis vulgaris

The roles of sialyl-Lewisx antigen were evaluated in the pathogenesis of psoriasis. Sialyl-Lewisx expression was investigated immunohistochemically in the epidermis of normal human skin and erythematous lesional skin of psoriasis vulgaris by avidin-biotin-peroxidase complex procedures. A few sialyl-Lewisx positive dendritic cells were detected in the epidermis of normal human skin. In 7 out of 9 cases of psoriasis vulgaris, the number of sialyl-Lewisx-positive epidermal dendritic cells increased in the erythematous lesion over the adjacent normal skin; there were no marked changes in the numbers of CD1a-positive cells in the epidermis between the two skin types. In the double immunofluorescence studies, more than half of the sialyl-Lewisx-positive epidermal cells in psoriatic erythema were stained with a monoclonal Lag antibody that specifically reacts with Birbeck granules and related structures of human Langerhans cells. Furthermore, we determined the changes in serum levels of sialyl-Lewisx antigens in patients with psoriasis. Although levels in the sera were not significantly elevated over those of controls, the increases correlated with the degree of disease activity. These findings suggest that sialyl-Lewisx antigen is possibly involved in the development of psoriasis.

Nitric oxide regulates NMDA-induced dopamine release in rat striatum

We investigated the effect of nitric oxide (NO) on N-methyl-D-aspartate (NMDA)-induced changes in levels of dopamine (DA) and its metabolite in the striatum using in vivo microdialysis. Local administration of 1mM NMDA into the striatum significantly augmented DA release in the striatum. Simultaneous administration of -5mM N(G)-nitro-L-arginine methyl ester (-NAME), a NO synthase inhibitor, into the striatum significantly potentiated NMDA-induced DA release. This effect of L-NAME was completely reversed in the presence of 50mM L-arginine (L-Arg). Administration of 1 mM NMDA significantly decreased the levels of dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA). This effect of NMDA was not affected by concurrent administration of L-NAME. This study provides in vivo evidence for the involvement of NO in NMDA-induced DA release.

Human ESP1/CRP2, a member of the LIM domain protein family: characterization of the cDNA and assignment of the gene locus to chromosome 14q32.3

The LIM domain is present in a wide variety of proteins with diverse functions and exhibits characteristic arrangements of Cys and His residues with a novel zinc-binding motif. LIM domain proteins have been implicated in development, cell regulation, and cell structure. A LIM domain protein was identified by screening a human cDNA library with rat cysteine-rich intestinal protein (CRIP) as a probe, under conditions of low stringency. Comparison of the predicted amino acid sequence with several LIM domain proteins revealed 93% of the residues to be identical to rat LIM domain protein, termed ESP1 or CRP2. Thus, the protein is hereafter referred to as human ESP1/CRP2. The cDNA encompasses a 1171-base region, including 26, 624, and 521 bases in the 5'-noncoding region, coding region, and 3'-noncoding regions, respectively, and encodes the entire ESP1/CRP2 of 208 amino acids (M(r), 22,496). Human ESP1/CRP2 protein has two LIM domains, and each shares 35.1% and 77 or 79% identical residues with human cysteine-rich protein (CRP) and rat CRIP, respectively. Northern blot analysis of ESP1/CRP2 in various human tissues showed distinct tissue distributions compared with CRP and CRIP, suggesting that each might serve related but specific roles in tissue organization or function. Using a panel of human-rodent somatic cell hybrids, the ESP1/CRP2 locus was assigned to chromosome 14. Fluorescence in situ hybridization, using cDNA and a genome DNA fragment of the ESP1/CRP2 as probes, confirms this assignment and relegates regional localization to band 14q32.3.

The receptor tyrosine kinase, Cek8, is transiently expressed on subtypes of motoneurons in the spinal cord during development

Receptor tyrosine kinases (RTKs) play important roles in cellular proliferation, differentiation, and survival. We performed reverse transcriptase-polymerase chain reactions (RT-PCR) from enriched embryonic day 5 (E5) chick motoneurons by panning to identify RTKs involved in the early development of motoneuron. In situ hybridization revealed that Cek8, a member of the eph family, was specifically expressed on motoneurons at the brachial and lumbar segments of the spinal cord which innervate limb muscles, and disappeared after the naturally occurring cell death period (E6-E11). Immunohistochemistry using an anti-Cek8 monoclonal antibody showed the localization of Cek8 protein at the cell bodies and axonal fibers of motoneurons and muscles. The unique expression of Cek8 suggests its involvement in cellular survival or cell-cell interactions for specific subpopulations of developing motoneurons.

[Quality control of surgery in multicenter study--interinstitutional and individual differences]

In a prospective randomized controlled trial (PRCT) of adjuvant chemotherapy for gastric cancer patients participated by 6 cancer center hospitals, inter-institutional and inter-individual differences about several factors related to the surgery and remote survivals were analyzed. From 1988 to 1992, 1,049 evaluable patients were enrolled and stratified to 6 groups according to the grade of the serosal invasion and curability, and analyzed statistically.

RESULTS

1) There were no inter-institutional differences about postoperative survival rate, but there were slight differences about patient's background factors and entry policy of each institution. 2) There were no inter-institutional differences about several factors related to the surgery such as operative time, bleeding volume during operation, and the length of the administration periods. 3) There were no inter-individual differences about the length of the administration periods, but there were a little differences about operative time and the volume of hemorrhage. When the PRCT of adjuvant chemotherapy of which the end point is survival would be designed, no inter-institutional differences about remote survival and surgical operation in each institution should be confirmed before starting the trial.

[Preliminary screening for antiviral AIDS drugs. VII. Report for fiscal year 1994]

Preliminary screening of antiviral AIDS drugs has been carried out using three different in vitro assay systems. Among 246 samples of different origin tested, six were shown to inhibit the growth of HIV in vitro. Two of the positive samples have hopeful signs, as the ranges of effective doses are wider than those of most of positive samples which had been found by us.

Novel designed enediynes: molecular design, chemical synthesis, mode of cycloaromatization and guanine-specific DNA cleavage

The molecular design and chemical synthesis of novel enediyne molecules related to the neocarzinostatin chromophore (1), and their chemical and DNA cleaving properties are described. The 10-membered enediyne triols 16-18 were effectively synthesized from xylitol (10) in a short step, and found to be quite stable when handled at room temperature. The representative and acylated enediyne 16 was cycloaromatized by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in cyclohexa-1,4-diene-benzene to give the benzenoid product 21 through a radical pathway. On the other hand, the enediyne 16 was cycloaromatized by diethylamine in dimethyl sulfoxide-Tris-HCl, pH 8.5 buffer to afford another benzenoid product 22 as a diethylamine adduct through a polar pathway. Furthermore, the enediynes 16-18 were found to exhibit guanine-specific DNA cleavage under weakly basic conditions with no additive.

[Serovar-distribution and drug-resistance of Salmonella strains isolated from domestic and imported cases in 1990-1994 in Tokyo]

A total of 3,647 non-typhoidal Salmonella strains consisting of 2,655 domestic strains and 992 imported strains isolated in Tokyo from 1990 to 1994, were examined for their serovar-distribution and their drug-resistance. The serological typing results showed that the domestic strains were classified into 15 O-groups and 96 serovars, and the imported strains were classified into 13 O-groups and 73 serovars. Among the serovars identified, Salmonella serovar Enteritidis (S. Enteritidis), S. Thompson, S. Hadar, S. Litchfield, and S. Tennessee were predominant in the domestic strains, whereas S. Hadar, S. Enteritidis, S. Anatum, S. Derby, and S. Blockley were predominant in the imported strains. The drug-resistance test using 9 drugs (CP, TC, SM, KM, ABPC, ST, NA, FOM, and NFLX) showed that 30.5% of the domestic strains and 40.5% of the imported strains were resistant to any of the drugs examined. The serovars of a high resistant rate during this period were S. Hadar (96.2%), S. Blockley (88.7%), S. Enteritidis (63.4%), S. Virchow (54.3%), and S. Typhimurium (51.3%) in the domestic strains and S. Krefeld (100%), S. Hadar (98.9%), S. Blockley (98.2%), S. Emek (83.3%), S. Kentucky (76.5%), S. Panama (69.2%), S. Derby (63.8%), S. Typhimurium (57.1%), S. Rissen (55.6%), and S. Agona (53.7%) in the imported strains. Drug-resistance patterns of the resistant isolates varied to 62 types. Prevalent patterns recognized were SM, TC.SM, TC.SM.KM, TC, TC.SM.KM.ABPC and CP.TC.SM.KM in the domestic strains and TC.SM, TC, CP.TC.SM.ST, TC.SM.KM, and CP.TC.SM.KM in the imported strains.

Expression of sarcoplasmic reticulum Ca2+ -ATPase mRNA in the hypertrophied heart of young spontaneously hypertensive rats

1. Recent evidence indicates that cardiac hypertrophy induced by pressure overload is associated with a decrease in sarcoplasmic reticulum (SR) Ca2+ -ATPase of myocytes, which may contribute to a diastolic dysfunction of the heart by causing intracellular Ca2+ overload. To elucidate whether or not this is also the case in genetic hypertension, we examined cardiac mRNA levels of SR Ca2+ ATPase in 11 week old spontaneously hypertensive rats (SHR) by northern blot analysis. 2. Furthermore, to test the effects of short-term inhibition of the renin-angiotensin system on its expression, we treated 10 week old SHR with angiotensin-converting enzyme inhibitors (alacepril and imidapril) or an AT1 receptor antagonist (SC-52458) for 7 days. 3. Though the left ventricular weight of SHR was significantly higher than that of Wistar-Kyoto (WKY) rats (277 +/- 6 vs 237 +/- 4 mg/100 g bodyweight, respectively, P < 0.05), the level of SR Ca2+ -ATPase mRNA showed no difference between SHR and WKY at this age. 4. Moreover, the aforementioned three drugs did not at all affect the SR Ca2+ -ATPase expression of SHR. 5. Thus, the expression of SR Ca2+ -ATPase was not down-regulated in the heart of 11 week old SHR, and seemed not to be mediated by angiotensin AT1 receptor at this age. Since some evidence on pressure-overloaded cardiac hypertrophy indicate that the decrease in SR Ca2+ -ATPase expression occur in prominent hypertrophy and in the failured heart, further studies on cardiac SR Ca2+ -ATPase expression in more aged SHR will be required.

Cerebral sparganosis mansoni--case report

An 80-year-old male with paresis of the right upper extremity underwent surgery for a suspected metastatic brain tumor. A live Sparganum mansoni worm was removed from the parietal lobe through a left parietal craniotomy. Retrospective evaluation of magnetic resonance (MR) images revealed ipsilateral ventricular dilatation, despite the presence of a mass lesion resembling a metastatic brain tumor. This interesting MR imaging finding is an important point for differentiating between a brain tumor and cerebral sparganosis.

[Species and serovar-distribution, and drug-resistance of Shigella strains isolated from imported and domestic cases from 1990 through 1994 in Tokyo]

A total of 446 Shigella strains consisting of 336 imported and 110 domestic strains isolated in Tokyo from 1990 to 1994 were examined for their species and serovar-distribution, and their drug-resistance. In both imported and domestic strains, S. sonnei was found to be the most prevalent species, followed by S. flexneri. In imported strains, however, the isolation frequency of S. flexneri, S. boydii and S. dysenteriae were higher than that of domestic strains, and the serovar of each species was distributed in a wider range than that of the domestic strains. Provisional new serovar Shigella strains were isolated from 8 imported cases and 2 domestic cases. The drug-resistance-test using 9 drugs (CP, TC, SM, KM, ABPC, ST, NA, FOM, and NFLX) showed that 82.7% of the imported strains and 89.1% of the domestic strains were resistant to any drugs examined. Drugs of a high resistant rate were SM, TC, ST for the both groups. Drug-resistance-patterns of the resistant isolates varied to 21 types. Among those, a triple drug-resistance-type with TC SM ST was found the most frequently in both groups. None of the strains were resistant to FOM or NFLX.

Suppression of vascular transforming growth factor-beta1 and extracellular matrix gene expressions by cilazapril and nifedipine in hypertensive rats

1. We investigated the protective effects of an angiotensin-converting enzyme inhibitor (ACEI) and a Ca antagonist on vascular injury in hypertension. 2. Thirteen week old stroke-prone spontaneously hypertensive rats (SHRSP) were orally given cilazapril (ACEI 10 mg per kg day) or nifedipine (Ca antagonist 30 mg kg per day) for 12 weeks. After the treatment, the aorta and superior mesenteric artery were excised, and subjected to the extraction of RNA. mRNA levels for the transforming growth factor-beta1 (TGF-beta1) and extracellular matrix components such as fibronectin (FN), collagen type I (CoI), type III (CoIII) and type IV (CoIV) and laminin, were measured by northern blot analysis, using each specific cDNA probe. 3. In the mesenteric artery of SHRSP, TGF-beta1 mRNA levels were increased compared with Wistar-Kyoto (WKY) rats, being accompanied by a significant increase in mRNA levels for FN, CoI, CoIII, CoIV and laminin. In the aorta, only TGF-beta1 and fibronectin mRNAs were increased in SHRSP, but collagen and laminin were not increased. 4. Both cilazapril and nifedipine, to similar extents, suppressed the above mentioned increased gene expressions in both mesenteric artery and aorta, being associated with the improvement of vascular hypertrophy. 5. These results suggest that TGF-beta1 may be responsible for smooth muscle cell hypertrophy and the increased deposition of extracellular matrix in hypertensive blood vessels. Both cilazapril and nifedipine may lessen hypertensive vascular thickening, by suppressing the gene expression of TGF-beta1 and extracellular matrix.

[Analysis of infiltrating lymphocytes in choroidal melanoma]

We performed immunohistochemistry on tumor infiltrating lymphocytes (TILs) in a 78-year-old man with choroidal malignant melanoma. Cell suspensions of TILs from fresh specimens and peripheral blood lymphocytes (PBLs) were stained with anti-CD3, anti-CD4, anti-CD8, anti-CD29, anti-CD45RA, and anti-human leukocyte antigen (HLA)-DR monoclonal antibodies and analyzed using three-color flow cytometry. In light microscopy, the number of infiltrating lymphocytes around the tumor was very small. Immunohistochemically, T lymphocytes were more numerous than B lymphocytes. Flow cytometric analysis showed that CD8+ cells were more numerous than CD4+ cells in CD3+ cells in TILs, and most of these cells also expressed HLA-DR antigen. CD29+ (memory) cells were increased and CD45RA+ (naive) cells were decreased in CD4+ cells in TILs as compared with PBLs. We concluded that the increase in the percentage of activated memory T lymphocytes and the decrease of naive T lymphocytes may reflect a localized antigen-specific immunological response in choroidal malignant melanoma.