Biomedical subjects

N Nishimura

Publications and source records attributed to N Nishimura.

At least 109 records · Page 6Linked to original sources

PubMed1997

[Efficacy and safety of intramuscular imipenem/cilastatin (IPM/CS) for complicated urinary tract infections].

An intramuscular preparation of imipenem/cilastatin (IPM/CS, 500 mg/500 mg) was administered to 59 patients with complicated urinary tract infections (UTI; cystitis and pyelonephritis) to evaluate its efficacy and safety. The obtained results are summarized as follows: In patients with cystitis, evaluations based on daily frequencies of administration were also performed. 1) According to the treating doctors, the drug showed an overall efficacy rate of 80% (45/56 patients). The efficacy rate was 89% in patients with cystitis treated by a u.i.d. regimen. Among patients treated by a b.i.d. regimen, the efficacy rate was 67% for cystitis cases and 84% for pyelonephritis cases. 2) When clinical efficacy was assessed according to the criteria for UTI drug efficacy evaluation, the drug was 'markedly effective' in 14 patients, 'effective' in 23, and ineffective in 11 patients, for an efficacy rate of 77% (37/48 patients). 3) The microbiological eradication rate was 88% (59/67 strains). The rate was 95% (20/21 strains) for Gram-positive bacteria and 85% (39/46 strains) for Gram-negative bacteria. The efficacy for Enterobacter faecalis and Pseudomonas aeruginosa was 100% and 73%, respectively. 4) As side effects, pain at the injection site was reported by one patient and abnormal laboratory test values were observed in 2 patients. All of these reactions were mild and resolved shortly after the completion of treatment. Based on these findings, it is concluded that this intramuscular preparation of IPM/CS is effective for treating complicated urinary tract infections.

Adolescent↗

PubMed1996

Cooperativity of stabilized mRNA and enhanced translation activity in the cell-free system.

Detailed analysis of cell-free translation, coupled transcription-translation in static conditions and a continuous flow system based on E. coli S30 extracts was performed. Degradation of template mRNA was the predominant trigger to terminate the protein synthesis. In a coupled system, mRNA was preserved by repeated transcription whereas the starvation of nucleotide triphosphates led to the termination of protein synthesis in less than 1 h. In the CFCF system, NTP was held at the level of initial concentration and therefore did not arrest the translation for 15 h. The accurate coupling of transcriptional rate and translational rate was also crucial to enhance the efficiency of protein synthesis.

Bacterial Proteins↗

PubMed1996

Testosterone-dependent induction of metallothionein in genital organs of male rats.

Metallothioneins (MTs) are a group of cysteine-rich heavy-metal-binding proteins. We have investigated MT gene expression in the ventral and dorsolateral lobes of the prostate and coagulating gland of male Wistar rats. In intact rats, both MT mRNA and MT were present in the dorsolateral lobe and coagulating gland but not in the ventral lobe. Orchidectomy caused involution of the above organs, and both MT mRNA and MT were considerably decreased or become undetectable. An injection of testosterone propionate into orchidectomized rats restored not only the size of these organs, but also MT mRNA and MT concentrations, particularly in the dorsolateral lobe and coagulating gland. In the dorsolateral lobe, no selective uptake of Zn2+ preceding the increase in MT was observed, suggesting that Zn2+ ions are not associated with the increased expression of the MT gene. The present result suggests that of the male auxiliary genital organs, the dorsolateral lobe and coagulating gland, but not the ventral lobe, contain MT, the biosynthesis of which is regulated by testosterone.

Animals↗

PubMed1996

The effect of docosahexaenoic acid on aggression in young adults. A placebo-controlled double-blind study.

41 students took either docosahexaenoic acid (DHA)-rich oil capsules containing 1.5-1.8 grams DHA/day (17 females and 5 males) or control oil capsules containing 97% soybean oil plus 3% fish oil (12 females and 7 males) for 3 mo in a double-blind fashion. They took a psychological test (P-F Study) and Stroop and dementia-detecting tests at the start and end of the study. The present study started at the end of summer vacation and ended in the middle of mental stress such as final exams. In the control group extraggression (aggression against others) in P-F Study was significantly increased at the end of the study as compared with that measured at the start (delta = +8.9%, P = 0.0022), whereas it was not significantly changed in the DHA group (delta = -1.0%). The 95% CI of differences between the DHA and control groups were -16.8 to -3.0%. DHA supplementation did not affect the Stroop and dementia-detecting tests. Thus, DHA intake prevented extraggression from increasing at times of mental stress. This finding might help understand how fish oils prevent disease like coronary heart disease.

Adult↗

PubMed1996

Saturable transport of valproic acid in rat choroid plexus in vitro.

In order to obtain in vitro evidence for a specific transport system of valproic acid (VPA) at the blood-cerebrospinal fluid (CSF) interface, the uptake of VPA by isolated rat choroid plexus was investigated. The uptake clearance of [3H]VPA decreased with the increase of the unlabeled VPA concentration in the incubation medium. Kinetic analysis yielded an apparent Km of 10.0 mM, Vmax of 0.0871 mumol s-1 g-1 and Kns, a permeability coefficient of the nonsaturable component, of 6.85 microL s-1 g-1, indicating that both saturable and nonsaturable systems may contribute to VPA uptake by choroid plexus. Organic anions, penicillin G, p-aminohippurate, salicylate, and probenecid significantly inhibited VPA uptake by choroid plexus. We suggest that VPA translocation through choroidal membrane is partly operated by the organic anion transport system. A significant decrease of VPA uptake induced by 2,4-dinitrophenol, stilbenedisulfonate, and hypothermia (10 degrees C) indicates the involvement of an energy-dependent, carrier-mediated transport system. These results demonstrate that VPA is actively transported through the rat choroidal epithelium via a saturable system probably shared by organic anions.

4-Chloromercuribenzenesulfonate↗

PubMed1996

Expression of estrogen receptor and proto-oncogene messenger ribonucleic acids in reproductive tracts of neonatally diethylstilbestrol-exposed female mice with or without post-puberal estrogen administration.

Perinatal treatment of female mice with natural and synthetic estrogens including diethylstilbestrol (DES) results in estrogen-independent persistent proliferation and cornification of the vaginal epithelium. The dynamics of the induction of estrogen receptor (ER), c-jun, c-fos and c-myc mRNAs by 17 beta-estradiol (E2) was examined in the uterus and vagina of neonatally DES-exposed and -unexposed ovariectomized adult mice. In the uterus of neonatally DES-unexposed ovariectomized mice, the expression of ER mRNA increased within 1 h after E2 administration and declined by 12 h thereafter. ER mRNA in the vagina decreased within 1 h after the stimulation and recovered by 12 h thereafter. In the uterus, c-jun and c-fos mRNAs increased in concentration within 1 h after E2 administration, showing a peak 3 h after the stimulation; they decreased with time thereafter. In the vagina, the concentration of c-jun and c-fos mRNAs increased rapidly, reaching a peak within 1 h after the stimulation. However, the expression of c-myc in uterus and vagina was not changed by postpuberal E2. These results suggest that estrogen regulation of ER and proto-oncogene mRNAs in the vagina differs from those in the uterus. In the neonatally DES-exposed ovariectomized adult mice, uterine ER mRNA expression levels were significantly higher than in the unexposed ovariectomized controls; however, vaginal levels were drastically lower than in the controls. Expression of c-jun and c-fos mRNAs was greater in both the uterus (3- and 6-fold, respectively) and the vagina (18- and 4-fold) of neonatally DES-exposed mice than in controls. The ER mRNA and the increased levels of c-fos and c-jun mRNAs in both uterus and vagina of neonatally DES-exposed ovariectomized mice were not further altered by post-puberal E2 and may be related to ovary-independent persistent changes in the genital tract.

Animals↗

PubMed1996

Evidence for developmentally regulated transcriptional, translational and post-translational control of metallothionein gene expression in hair follicles.

The distribution of metallothionein (MT) and MT mRNAs was examined in hair (wool) follicles, where high levels of cell proliferation are found and where the resulting cells provide a temporal record of differentiation events. MT was found in the cytoplasm and some nuclei of follicle bulb cells of the proliferative zone, outer root sheath cells and in basal layer cells of sebaceous glands and sweat glands. The population of 5-bromo-2'-deoxyuridine (BrdU)+ cells in these tissues overlapped, but were not completely coincident with the distribution of MT staining. MT mRNA expression in hair (wool) follicles was assessed by in situ hybridization with four gene-specific sheep MT (sMT) isoforms. Intense signals were obtained with the sMT-Ib probe in follicle bulb cells from the proliferative zone to the keratogenous zone. Signals from the sMT-Ia probe were present in the same cells, but were much weaker. No signals were detected using the sMT-Ic and sMT-II gene-specific probes. The findings suggest that: (1) MT is important in cell proliferation and/or cell differentiation in the hair follicle bulb; (2) MT translation is inhibited during cell differentiation and migration; and (3) tissue-specific expression of uncharacterized sMT isoforms is likely.

Animals↗

PubMed1996

Synthesis and structure-activity relationships of novel phenylcyanoguanidine derivatives as potassium channel openers.

3,5-Di-substituted phenylcyanoguanidine derivatives with halogen, cyano and/or nitro groups at the 3- and 5-positions of the benzene ring exhibited very strong smooth muscle relaxation activity in vitro, as compared to pinacidil. Among them, N-(3-chloro-5-cyanophenyl)-N'-cyano-N" -tert-pentylguanidine (5s) showed 27-fold more potent activity than pinacidil, and exhibited a stronger and more lasting antihypertensive effect than pinacidil by oral administration to spontaneously hypertensive rats. We propose a new pharmacophore model in which the essential factors for binding to the potassium channel are an NH and a bulky alkyl group.

Animals↗

PubMed1996

Effect of aging on the esophageal motor functions.

To clarify the changes of esophageal motility along with age, we performed esophageal manometry on 47 healthy volunteers, and compared the values of four groups under 49 years old (n = 11), 50 to 59 (n = 15), 60 to 69 (n = 11), and over 70 years old (n = 10). Resting lower esophageal sphincter (LES) pressure in the group over 70 years old showed the tendency of decrease, but not statistically significant. Nadir LES pressure on swallow-induced relaxation was not statistically different among 4 groups. On esophageal body testing, percentage of non-conduction sequence in the group 60 to 69 and over 70 years old was statistically higher compared with that of the group under 49 years old (p < 0.05) but spared in some elderly subjects. Percentage of simultaneous contractions was not statistically different among 4 groups. Peristaltic contraction amplitude in the group over 70 years old was significantly lower than that of the group under 49 years old both at the level of 5 cm above (p < 0.01) and 10 cm above LES (p < 0.05). We speculate that the influence of aging on esophageal motility is the reduced transmission sequence of peristalsis and contractility of esophageal body. This alteration along with age may differ from the pathological condition of scleroderma or diffuse esophageal spasm.

Adult↗

PubMed1996

Effect of estrogen on ontogenic expression of progesterone and estrogen receptors in rat uterus.

The ontogenic expression of progesterone and estrogen receptors (PR and ER) and effect of estrogen on these receptors were investigated immunohistochemically in rat uterus from the day of birth ( = 0 day) to 30 days of age. Uterine epithelial and stromal cells showed a negative PR immunoreaction at 0 day. The PR in the epithelial cell nuclei appeared by 5 days, while the stromal cells showed a negative PR reaction until 12 days. The staining of the stromal cells appeared from 12 to 15 days. In both the epithelial and stromal cells, the initiation of the PR appearance was not affected by ovariectomy performed at 0 day or 5 days prior to the appearance of PR in the epithelial and stromal cells. Estrogen injections from 0 day failed to initiate the appearance of PR in the epithelial cells, regardless of doses of estradiol-17 beta (0.1, 1 and 10 micrograms daily), but induced PR in the stromal cells. The staining of ER appeared at 5 days in the epithelial cells and at 1 day in the stromal cells, respectively. ER appeared after 2-3 daily injections of estrogen from 0 day depending upon the doses. These results suggest that steroid hormones secreted from neonatal ovary do not play any important role in ontogenic expression of PR during the postnatal uterine maturation.

Animals↗

PubMed1996

[A 4-week oral toxicity study of prulifloxacin (NM441) in rats followed by a 4-week recovery test].

A repeated dose toxicity study of prulifloxacin, a new antibacterial agent, was conducted in Sprague-Dawley rats. Male and female rats were given the test material orally for 4 weeks at doses of 0 (control), 30, 300 and 3000 mg/kg. After discontinuation of the treatment, a 4-week recovery test was also conducted. There was one case of death in the 3000 mg/kg group. Grayish green and soft feces, unkempt fur, transient deep respiration and decreased body weight gain were observed in the 3000 mg/kg group. Decreased food consumption and increased water intake were seen in the 300 and 3000 mg/kg groups. Ophthalmoscopic examination failed to show any abnormalities related to the treatment. In urinalysis, crystalline substance in the urinary sediments, cloudy urine and decreased Na+ excretion were observed in the 300 and 3000 mg/kg groups. Increased urine volume, lowered urine specific gravity and decreased K+ and Cl- excretions were seen in the 3000 mg/kg group. Hematologic examination showed decreased Hb, Ht, MCV and MCH and increased WBC in the 3000 mg/kg group. Blood chemical examination revealed increased BUN and decreased K+ and Cl- in the 3000 mg/kg group, and decreased K+ and gamma-globulin in the 300 mg/kg group. Pathological changes caused by the treatment were as follows. Cecal weight was increased in all dose groups. Cecal distention and swelling of its absorptive cells were seen in the 300 and 3000 mg/kg groups. In kidney, tubular nephrosis with crystalline substance was observed in the 300 and 3000 mg/kg groups, and its organ weight was increased in the 3000 mg/kg group. The above-mentioned changes were reversible except for decreased gamma-globulin, increased BUN and urine volume, and lowered urine specific gravity. Ulcer and small cavities associated with proliferation of fibrous tissue in the femoral articular cartilage were observed in the 3000 mg/kg group at the end of recovery period of 4 weeks. Plasma levels and urinary concentrations of active metabolite of the test material were increased in all dose groups with dose-related manner, whereby no sex difference was observed. No effects caused by the repeated dosing were seen in the plasma concentrations. Increased cecal weight in the 30 mg/kg group was considered to be attributable to the pharmacological effect of the test material. The results show that the NOAEL of prulifloxacin is 30 mg/kg for 4-week repeated dose toxicity in rats.

Administration, Oral↗

PubMed1996

A description and morphometric comparison of eggs from eight geographic populations of the South American malaria vector Anopheles (Nyssorhynchus) nuneztovari (Diptera:Culicidae).

The egg of Anopheles nuneztovari is described from scanning electron micrographs of specimens collected from western Venezuela. Morphometric measurements of egg samples from 3 localities in Venezuela, one in Suriname, and 4 in Brazil are compared and relationships analyzed by multivariate statistics. Morphological characters were similar in 2 geographical groups, one Venezuelan and the other Amazonian, that were distinguishable on the basis of differences in size and density of tubercles in the anterior deck region and area of pores in the dorsal plastron. Eggs from western Brazil did not cluster with other Amazonian collections. The distinction of Venezuelan from Amazonian eggs of An. nuneztovari is consistent with chromosomal, ecologic, and molecular evidence for regional genetic differentiation in this species.

Animals↗

PubMed1996

[A study on peak expiratory flow monitoring maneuver as compared to forced expiratory flow maneuver].

In this study, we tried to clarify the characteristics of peak expiratory flow (PEF) measurement maneuver as a tool of daily monitoring severity of asthma in accordance with peak expiratory flow rate (PEFR) of forced expiratory maneuver. PEF did not differ when measured either in the standing or sitting position. However, obese individuals may have higher PEF when measured in the standing position and subjects with emphysematous change may have higher PEF when measured in the sitting than in the standing position. PEF did not differ when measured either with or without nose clip. Expiration time and volume in PEF measurement requires only one fifth and a half of that of forced expiratory flow volume measurement, respectively. In 36% of asthmatic patients in whom PEF is measured daily, PEF measurements were thought to be measured after inspiring at about 90% of forced vital capacity. Although PEF is a well tolerated useful clinical parameter in the management of bronchial asthma, it has different characteristics from peak expiratory flow rate (PEFR) of forced expiratory volume measurement.

Adult↗

PubMed1996

Systemic chemotherapy alters interleukin-1 beta and its receptor antagonist production by human alveolar macrophages in lung cancer patients.

The purpose of this study was to determine whether cytotoxic chemotherapy influences the number and function of alveolar macrophages (AM) in patients with lung cancer. AM were obtained by bronchoalveolar lavage from 24 patients with lung cancer and 17 control patients. The functional integrity of AM was determined by their ability to produce interleukin-1 beta (IL-1 beta) and interleukin-1 receptor antagonist (IL-1ra) before and after platinum-containing systemic chemotherapy. The productions of IL-1 beta and IL-1ra were quantitated by enzyme immunoassays. The proportions of multinucleated cells among AM were significantly decreased after systemic chemotherapy in lung cancer patients. No significant difference in spontaneous and lipopolysaccharide (LPS)-stimulated IL-1 beta or IL-1ra production by AM was observed between lung cancer patients and control patients. Significant increase of IL-1 beta and significant decrease of IL-1ra production by AM were demonstrated in patients with small cell lung cancer who experienced response to systemic chemotherapy. These results suggest that systemic chemotherapy may influence functional roles of AM in the lung, and consideration of influence of systemic chemotherapy on host functions is important in cancer treatment.

Adult↗

PubMed1995

Molecular cloning and chromosomal assignment of the human brain-type phosphodiesterase I/nucleotide pyrophosphatase gene (PDNP2).

Phosphodiesterase I/nucleotide pyrophosphatase is a widely expressed membrane-bound enzyme that cleaves diester bonds of a variety of substrates. We have cloned brain-type cDNA for this enzyme from rat brain and designated it PD-I alpha (M. Narita, J. Goji, H. Nakamura, and K. Sano, 1994, J. Biol. Chem. 269: 28235-28242). In this study we have isolated cDNA and genomic DNA encoding human PD-I alpha. Human PD-I alpha cDNA, designated PDNP2 in HGMW nomenclature, has a 2589-nucleotide open reading frame encoding a polypeptide of 863 amino acids with a calculated M(r) of 99,034. Northern blot analysis revealed that human PD-I alpha transcript was present in brain, lung, placenta, and kidney. The database analysis showed that human PD-I alpha was identical with human autotaxin (ATX), a novel tumor motility-stimulating factor, except that human PD-I alpha lacks 156 nucleotides and 52 amino acids of human ATX. Human PD-I alpha and human ATX are likely to be alternative splicing products from the same gene. The 5' region of the human PDNP2 gene contains four putative binding sites of transcription factor Sp1 without typical TATA or CAAT boxes, and there is a potential octamer binding motif in intron 2. From the results of fluorescence in situ hybridization, the human PDNP2 gene is located at chromosome 8q24.1.

Base Sequence↗

PubMed1995

Cloning of a brain-type isoform of human Rab GDI and its expression in human neuroblastoma cell lines and tumor specimens.

Rab proteins, a family of Ras-related small GTP-binding proteins, play a key role in regulating intracellular vesicle trafficking. Rab GDP dissociation inhibitor (GDI3) forms a soluble complex with Rab proteins and thereby prevents the exchange of GDP for GTP. Recently, two isoforms of Rab GDI cDNA were isolated from rats and mice. In this study, we have isolated a brain-type isoform of human Rab GDI cDNA and examined its expression in neuroblastoma. We tentatively designate it as human Rab GDI alpha (hu GDI alpha) and another human Rab GDI, as human Rab GDI beta (hu GDI beta). Hu GDI alpha cDNA encodes a protein of 447 amino acids with a deduced molecular weight of 50,200. Northern blot analysis revealed that hu GDI alpha gene is expressed abundantly in the brain but much less in other tissues, while hu GDI beta gene is ubiquitously expressed. All human neuroblastoma cell lines and tumor specimens examined express hu GDI alpha gene to various extents, while a human T cell leukemia cell line, MOLT3, does not. The levels of both hu GDI alpha and beta mRNA were constant in a human neuroblastoma cell line, NB1, during its neuronal differentiation, while Rab3A and neurofilament-L gene expression and the number of neurosecretory granules were elevated at this condition. These results suggest that hu GDI alpha gene expression is not related to the differentiation state of neuronal cells.

Amino Acid Sequence↗

PubMed1995

Improvement of Escherichia coli cell-free system by utilization of cell extract having additional property. Problems and countermeasures.

In the Escherichia coli cell-free system, the modification of cell extract can be achieved by preparation of the strains carrying additional property or those being induced with a certain gene expression prior to harvesting. In this study, we analyzed the cell-free system with S30 extract containing T7 RNA polymerases (S30 extract-T7pol) prepared from E. coli BL21(DE3) strain, which includes T7 RNA polymerase from extrinsic genes by IPTG induction, as a model for the improvement of the cell-free system. The fact that a significant degree of mRNA degradation was observed in the cell-free system with S30 extract-T7pol indicates the increase of ribonuclease activity was an unfavorable influence derived from the cell-extract modification process. We also showed that this influence was settled by the addition of an effective ribonuclease inhibitor, such as copper (II) ion, to the reaction mixture.

Copper↗

PubMed1995

Serum aminotransferase levels as an indicator of the effectiveness of venesection for chronic hepatitis C.

BACKGROUND/AIMS: Iron cytotoxicity may play an important role in chronic hepatitis C. The effects of venesection suggest that a slight iron overload contributes to hepatic injury in subjects infected with hepatitis C virus. A better indication of the efficacy of venesection was studied in patients with and without overt iron overloading. METHODS: All 40 patients had chronic hepatitis C but none had hemochromatosis of a known etiology. A serum ferritin level of 10 ng/ml or less was chosen as the treatment goal. A mean blood volume of 2400 +/- 1100 ml was removed during treatments lasting 5 +/- 3 months. RESULTS: Treatment significantly reduced the mean serum levels of alanine aminotransferase activity from 128 +/- 74 to 63 +/- 28 IU/l (p < 0.01). The baseline enzyme activity was highly correlated with reduction in activity after treatment (r = 0.94, p < 0.01), but the baseline levels of ferritin and histochemistry for iron showed poor correlations with the reduction in enzyme activity (r = 0.63 with p < 0.01 and r = 0.38 with p < 0.05, respectively). CONCLUSIONS: Thus, serum levels of aminotransferases were a more important indicator for venesection than conventional indices of iron overload, probably because cytotoxic iron includes some reactive iron species rather than stored iron alone.

Adult↗