Biomedical subjects

M Taguchi

Publications and source records attributed to M Taguchi.

At least 37 records · Page 2Linked to original sources

PubMed1997

[Studies on bacillary dysentery cases of overseas travellers--during 1979 to 1995].

A total of 36,780,440 overseas travellers during 1979-1995 (17 years) were quarantined at Osaka and Kansai Airport Quarantine Station, 84,777 travellers reported themselves suffer from diarrhoea. Stools from 29,587 persons were bacteriologically examined. Various enteropathogenic bacteria were isolated from 9,766 (33.0%) patients of the stools examined. Isolated species were as follows: Plesiomonas shigelloides (3,234 cases); Salmonella spp. (2,236 cases); enterotoxgenic Escherichia coli (1,621 cases); Vibrio parahaemolyticus (1,959 cases); and Shigella spp. (1,242 cases). 1,278 different Shigella strains were isolated from 1,242 cases who were thus diagnosed as bacillary dysentery patients. The suspected regions or countries for infection of these cases were analysed. The serovars and antibiotic-sensitivities of the isolated strains were examined. Colicine typing of S. sonnei strains were also done. The results can be summarized as follows. 1) The most cases (53.4%) were infected in India. 2) The percentage distribution of sub-species of the strains was as follows; S. sonnei (57.8%), S flexneri (29.8%), S. boydii (8.4%), and S. dysenteriae (4.0%), respectively. 3) The major colicine type of S. sonnei strains were type 6 and 0. 4) The percentage of Antibiotic-resistant strains of each sub-species was S. dysenteriae (92.2%), S. sonnei (89.4%), S. flexneri (87.1%), and S. boydii (84.9%), respectively. The percentage of Antibiotic-resistant strains of S. flexneri were increased annually.

Adolescent↗

PubMed1997

[Effect of nitrous oxide on spinal dorsal horn WDR neuronal activity in cats].

The effects of nitrous oxide (75%) on the spinal dorsal born wide dynamic range (WDR) neuronal activity were studied in either spinal cord intact or spinal cord-transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left bind foot pads of intact or decerebrate, spinal cord-transected (L 1-2) cats. The experiment was divided into four sections as follows: (1) When 10 micrograms of bradykinin (BK) was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cord-transected cat, all of 6 WDR neurons gave excitatory responses which were not depressed by 75% nitrous oxide. (2) When the injection of 10 micrograms of BK into the femoral artery ipsilateral to the recording site was used in the spinal cord-intact cat, 6 of 15 WDR neurons (40%) gave excitatory responses, which were significantly depressed by 75% nitrous oxide, and 9 of 15 WDR neurons (60%) gave inhibitory responses, which were not affected by 75% nitrous oxide. (3) When 10 micrograms of bradykinin (BK) was injected into the femoral artery contralateral to the recording site as the noxious test stimulus in the spinal cord transected cat, 6 of 12 WDR neurons gave excitatory reasons, which were not depressed by 75% nitrous oxide. (4) When the injection of 10 micrograms of BK into the femoral artery contralateral to the recording site was used in the spinal cord-intact cat, 6 of 6 WDR neurons (100%) gave responses, which were affected by 75% nitrous oxide. We have observed that nitrous oxide reduces the excitation and inhibition of dorsal born WDR neuronal activities induced by BK injection in spinal cord-intact cats, but does not reduce the excitation of those in spinal cord-transected cats. This finding confirmed that the antinociceptive effect of nitrous oxide might be modulated by supraspinal descending inhibitory control systems. In addition our result showed that the supraspinal effect of nitrous oxide was mediated not only by an increase but also a decrease in a supraspinal descending inhibition.

Action Potentials↗

PubMed1997

[The effects of isoflurane on the formalin-induced activity in the spinal dorsal horn of transected cat].

Although the formalin test is widely used in rodents, the electrical response to this stimulus and the effect of isoflurane on this response, has not been well understood in cats. We have therefore examined the effect of isoflurane on spinal wide-dynamic-range neuronal activity evoked by a subcutaneous (s.c.) formalin injection in cats. In decerebrate, spinal cord-transected cats (L 1-2), a s.c. injection of formaldehyde solution (0.05 ml; 5%) was performed in the receptive fields of spinal wide-dynamic-range neurons at the hind paw. Isoflurane (1.5%) inhalation was given 20 mins prior to formalin injection or 5 mins after the formalin injection. The formalin injection elicited an immediate and continuous discharge or burst activity in the neurons that lasted at least 90 min. Inhaled isoflurane was found to markedly inhibit this neuronal discharge. At 30 mins after discontinuing of isoflurane, the neuronal activity in both groups recovered to approximately 55% of the control value. These results suggest that formalin injection will reliably produce a continuous burst of neuronal activity in the spinal dorsal horn of cats, and that this activity can be markedly reduced by isoflurane. The ability of isoflurane to inhibit this neuronal response was not temporally related to the formalin injection.

Administration, Inhalation↗

PubMed1996

Evaluation of a new solution containing trehalose for twenty-hour canine lung preservation.

We examined the efficacy of two new preservation solutions containing trehalose--an extracellular type (ET-K) of solution and an intracellular type (IT-K) of solution--in relation to that of Euro-Collins (EC) solution in 20-h canine lung preservation. Canine lungs were flushed with one of the three solutions (n = 5 for each solution) after pretreatment with PGE1 (20 micrograms/kg) and were stored for 20 h at 4 degrees C. The left lungs were transplanted and evaluated to 6 h post transplant. In the ET-K group, the arterial oxygen tension after reperfusion was significantly higher than in the IT-K and EC groups. The pulmonary vascular resistance, wet/dry weight ratio, and histological evaluation of each transplanted lung in the ET-K group were also better than in the IT-K and EC groups. This indicates that ET-K solution is useful for 20-h preservation of canine lung grafts.

Analysis of Variance↗

PubMed1996

Studies on the site of ethanol action in inducing prolactin release in male rats.

Hypersecretion of prolactin (PRL) has been implicated as one of the factors that mediate ethanol-induced hypogonadism, but the site(s) in the central nervous system where ethanol acts to lead to the stimulation of PRL secretion is unknown. To clarify the site(s) of ethanol action, medial basal hypothalamic deafferentation (MBHD) or medial basal hypothalamic ablation (MBHA) were performed stereotaxically in male rats, and their PRL secretory capacity in response to acute ethanol administration was compared with that of intact or sham-operated controls. In intact control rats, plasma immunoreactive PRL concentration increased markedly (P < .001 v saline injection) following ethanol 400 to 500 mg/100 g body weight (BW) intraperitoneally (IP). The PRL response was dose-related and reached a maximum plateau level at 15 minutes. Plasma PRL returned to a near-basal level by 60 minutes. The response was blocked completely (P < .001) by pretreatment with dopamine (1 mg per rat), a specific inhibitor of adenohypophyseal PRL secretion. In sham-operated rats and in MBHD and MBHA rats, ethanol (500 mg/100 g BW IP) induced a significant (P < .001 to .05) elevation of PRL relative to the respective saline treatment. The basal level was significantly (P < .005) lower in the MBHD group (5.3 +/- 0.9 ng/mL) and significantly (P < .001) higher in the MBHA group (101.1 +/- 15.7 ng/mL) than in the sham group (17.2 +/- 5.9 ng/mL). These results suggest the following: (1) acute ethanol administration stimulates PRL secretion from the pituitary in a dose-related manner, (2) ethanol appears to have direct stimulatory effects on adenohypophyseal PRL secretion, and (3) extrahypothalamic brain areas exert a stimulatory influence and the hypothalamus an inhibitory influence on basal PRL secretion.

Animals↗

PubMed1996

Hemodynamic effects of intravenous ephedrine in infants and children anesthetized with halothane and nitrous oxide.

The aim of this study was to evaluate the effect of age on the hemodynamic responses to intravenous (IV) ephedrine in pediatric patients anesthetized with halothane, nitrous oxide, and oxygen. One hundred ten pediatric patients, ranging in age from 0.1 to 15 yr, were assigned to receive 0.1 mg/kg (n = 55) or 0.2 mg/kg (n = 55) IV ephedrine. General anesthesia was maintained with 1.0 minimum alveolar anesthetic concentration (MAC) of halothane and 67% nitrous oxide in oxygen after tracheal intubation. Measurements of arterial blood pressure and heart rate were made at 1-min intervals for 10 min after ephedrine 0.1 or 0.2 mg/kg was injected IV as a bolus. Significant correlations were noted between age and changes in mean blood pressure (r = 0.37, P < 0.01 for the subjects receiving ephedrine 0.1 mg/kg; r = 0.63, P < 0.001 for the subjects receiving ephedrine 0.2 mg/kg), but not between age and changes in heart rate. The present results indicate that age correlates with the pressor but not the chronotropic effects of ephedrine in pediatric patients anesthetized with 1 MAC halothane and nitrous oxide.

Adolescent↗

PubMed1996

[Bacteriological studies of travellar's diarrhoea. 5) Analysis of enteropathogenic bacteria at Osaka Airport Quarantine Station from January 1992 through September 3rd, 1994].

During the last 2 years and 8 months before the closure of Osaka Airport Quarantine Station (from Jan. 1992 to Sep. 3, 1994), a total of 7,421,909 overseas travellers were quarantined. 15,919 reported themselves of suffering from diarrhoea. Bacteriological examination of a total of 6,031 individuals' stools were performed. 1) Various enteropathogenic bacteria were isolated from 31.2% of the stools examined. Isolated species were as follows: Plesiomonas shigelloides, 1,127 cases (59.9%); Vibrio parahaemolyticus, 293 cases (15.6%); Salmonella spp., 262 cases (13.9%); Shigella spp., 235 cases (12.5%); Aeromonas sobria, 93 cases (4.9%); V. cholerae non-O1, 69 cases (3.7%). 2) The enteropathogenic bacteria were isolated through out the year without any seasonal variation. 3) The major regions where the travellers were infected with the pathogens are as follows: V. cholerae non-O1 (NAG Vibrio) and enteropathogenic Escherichia coli, South-East and South-West Asia; Vibrio other than NAG, South-East and East Asia; Shigella, widely distributed but especially in India; P. shigelloides and Salmonella, widely distributed. 4) 2 strains of toxigenic (cholera toxin-producing) V. cholerae O139 were isolated from patients who had visited Indonesia and Thailand, respectively. 5) In 320 cases (17%), plural enteropathogenic bacteria were isolated from single patients, suggesting a high frequency of the mixed infections. 6) Among Shigella strains, S. sonnei were isolated the most, followed by S. flexneri (24.7%), S. boydii (8.8%) and S. dysenteriae (2.9%). 7) Among Salmonella serovers, Salmonella Enteritidis was isolated the most frequently (39 cases, 14.1%). 8) 218 (91.6%) of 238 Shigella strains and 103 (37.6%) of 276 Salmonella strains were resistant to one or more drugs tested (SM.CP.TC.KM.ABPC.NA.OFLX). 9) All of the 22 V. cholerae O1 strains were Ogawa, E1 Tor. Among them, 19 were toxigenic strains and 3 were non-toxigenic. 10) O4:K8 was the most frequently isolated serover of V. paraemolyticus. 87.4% of all V. parahaemolyticus strains were positive with thermostable direct hemolysin (TDH) gene, and 12.6% of them were positive with TDH-related hemolysin (TRH) gene by DNA-probe methods.

Diarrhea↗

PubMed1996

[Serological assay for diagnosis of verotoxin-producing Escherichia coli (VTEC) infection in the patients with diarrhea].

A total of 239 serum samples from 136 persons were used for bacterial agglutination assay (BA) against predominant three O-antigens of VTEC. All VTEC isolates from stools of 30 patients were only O157:H7 serotype (these patients are called group I). The levels of positive BA antibody titers (over 1:160) to O157-antigen were recognized in each patients as follows. The VTEC isolated patients with HUS or without HUS in group I were all of 13 (100%) and 14 (82.4%) in 17 patients, respectively. And 21 (65.6%) patients of group II (HUS patients with stool negative cultures, or stool cultures were not performed in 32 patients), and 6 (15.0%) patients of group III (family members of group I and II; 40 persons), were also recognized. In group IV (patients with diarrhea due to other pathogen than VTEC; 11 patients), and V (clinically healthy persons; 23 persons), none were recognized as positive BA antibody titers. All patients in the group II except one who had a positive BA antibody titer to O111, were not recognized to O111 and O26. A few VTEC-positive patients without gastrointestinal syndrome did not have significant agglutinating titers to O157-antigen on the days after VTEC isolation. However, almost all patients with diarrhea due to VTEC and HUS, and with VTEC but no HUS, had a level of positive BA antibody titer on the 5 day after onset of diarrhea. These results suggest that this serological assay is a very simple and useful tool for diagnosis of VTEC infection when VTEC are not detected by culture method due to antimicrobial treatment, or due to the lapse of many days after onset of diarrhea.

Antibodies, Bacterial↗

PubMed1996

Effects of green tea and tea catechins on the development of mammary gland.

To find whether green tea and tea catechins have effects on the development of mammary glands, virgin DDD mice were fed on diets containing green tea and tea catechins. The degree of mammary gland development was examined by duct-alveolar growth and DNA content. The results indicated that green tea, but not tea catechins, has a growth-promoting effect on mammary gland development.

Animals↗

PubMed1996

[Pre-emptive analgesia from intravenous administration of opioid: no effect with pentazocine].

The influence of timing of administration of preoperative pentazocine on pain and analgesic requirements after surgery was studied in 46 patients undergoing total abdominal hysterectomy. Twenty-three patients received thiamylal 5 mg.kg-1 on induction of anesthesia, followed by pentazocine 30 mg or 60 mg before surgical incision (group A). Twenty-three control patients received pentazocine 30 mg or 60 mg, 5 min after abdominal incision (group B). The visual analogue scales for pain 24 h after operation were 6.0 cm at 30 mg dose in group A or 5.3 cm at 60 mg dose in group A and 5.7 cm at 30 mg dose in group B or 4.7 cm at 60 mg dose in group B. There were no differences in the visual analogues scales. Pentazocine consumption in the first 24 h after surgery was 67.5 mg at 30 mg dose in group A or 52.5 mg at 60 mg dose in group A and 70.9 mg at 30 mg dose in group B or 51.8 mg at 60 mg dose in group B. We conclude that postoperative pentazocine consumption and pain scores are no different when pentazocine is given before or after skin incision for abdominal hysterectomy and that there is no clinically useful pre-emptive analgesic effect with these doses of pentazocine.

Adult↗

PubMed1995

Endothelin synthesis and receptors in human endometrium throughout the normal menstrual cycle.

This study was undertaken to investigate the presence of messenger RNA (mRNA) for prepro-endothelin-I (ET-1) and the known receptor subtypes (ETA and ETB) in human endometrium at different stages of the menstrual cycle obtained at hysterectomy. Northern blot analysis revealed expression of ET-1 mRNA in human endometrium during the normal menstrual cycle. The concentration of ET-1 mRNA in endometrial tissue was greater during the menstrual and proliferative phases than during the ovulatory and secretory phases. Immunoreactive ET-1 was secreted into the medium of isolated endometrial stromal cells. Oestradiol and progesterone significantly attenuated ET-1 release in endometrial stromal cells cultured for 6 days. ETA and ETB mRNA were also present in endometrial tissue of the normal cycle. The concentration of ETA receptor mRNA was greater in the proliferative phase than in the secretory phase, whereas expression of ETB mRNA increased in menstrual phase. ET-1 significantly increased extracellular accumulation of cyclic AMP (cAMP), intracellular generation of inositol phosphates and significantly enhanced DNA synthesis in cultured endometrial stromal cells from the proliferative phase. Our results showed that human endometrial cells synthesized and released ET-1, and contained ETA and ETB receptors which were functionally coupled to phosphoinositide breakdown and to adenylate cyclase with the increase of cAMP by ET-1 stimulation. Our findings suggest that ET-1 may have a potential autocrine and/or paracrine function in human endometrial stromal cells.

Cells, Cultured↗

PubMed1995

Attempt to discriminate between bovine viral-diarrhoea virus strains using polymerase chain reaction.

The polymerase chain reaction (PCR) was applied to detect bovine viral-diarrhoea mucosal-disease virus (BVDV). By the use of properly prepared primers, cytopathogenic NADL, Oregon C24V, Nose, T-20 and KS86-1(+) strains, and non-cytopathogenic New York-1, No. 12, and KS86-1(-) strains could be detected. The PCR system was applied to field isolates of the viruses. All the viruses were detected by the PCR. Four patterns of the PCR amplification were recognized, and it was possible to discriminate between some strains. These results corresponded with the serotype of BVDV, as determined by the serum-neutralizing test. The BVDV gene was detectable from the leucocytes of infected cattle using the PCR method. Moreover, it was possible to detect and discriminate BVDV strains using one PCR tube that included all primer pairs.

Animals↗

PubMed1995

Linkage of the athymic nude locus with the myeloperoxidase locus in the rat.

In rats of the BUF/Mna strain epithelial thymoma development is regulated by a single autosomal susceptible gene, Tsr-1. In pre-thymoma stage, BUF/Mna rats have extremely large thymuses, when compared with those of other strains of rats. The large thymus size of this strain is contributed by a thymus-enlargement gene, Ten-1. On the other hand, reduced thymus size and suppression of thymoma development were found in heterozygous BUF/Mna-rnu/+ rats. Linkage studies between RNU and microsatellite and restriction fragment length polymorphism markers in ([BUF/Mna-rnu/rnu x WKY/NCrj] F1 x WKY/NCrj)- and (WKY/NCrj x [BUF/Mna-rnu/rnu x WKY/NCrj] F1)- backcross rats have led to the localization of RNU on chromosome 10. The rat homolog of mouse Mpo (myeloperoxidase) was also assigned to the chromosome 10. The gene order on the chromosome was MYHSE (myosin heavy chain of embryonic skeletal muscle)--(1.0 centimorgan [cM])--SHBG (sex hormone-binding globulin)--(4.0 cM)--RNU (Rowett rat nude)--(10.0 cM)--MPO--(13.0 cM)--AEP (anion exchange protein). Conserved linkage of homologous loci mapped to rat chromosome 10 and mouse chromosome 11 supports the hypothesis that the RNU and MPO loci are rat homologs of the mouse nu and Mpo loci.

Animals↗

PubMed1995

Stimulation of human periodontal ligament fibroblast collagenase production by a gingival epithelial cell-derived factor.

To examine whether cell-to-cell interactions between human gingival epithelial cells (HGE) and periodontal ligament fibroblasts (PLF) or gingival fibroblasts (GF) take place in the periodontium, the effects on collagenase production by PLF and GF were analyzed after adding several concentrations of HGE-conditioned medium (HGE-CM) to PLF or GF culture. Collagenase production by both cell populations was stimulated by adding HGE-CM, which stimulated collagenase production by PLF to a greater extent than that by GF. The HGE-derived stimulatory factor had a molecular mass of approximately 20 kDa, and its stimulant effect was inhibited markedly in the presence of an anti-human interleukin-1 alpha (IL-1 alpha) neutralizing antibody, indicating that the factor was identical to, or antigenically cross-reactive with, IL-1 alpha. These results suggest that epithelial apical migration in the periodontium may occur after interstitial resident cells have released tissue-degrading enzymes, such as collagenase, and damaged the extracellular matrix, once a sufficient amount of IL-1 alpha-like factor for stimulating the production of proteolytic enzyme has been released by HGE in periodontal lesions.

Cells, Cultured↗

PubMed1995

Direct effect of danazol on the DNA synthesis and ultrastructure of human cultured endometrial stromal cells.

The direct effect of danazol on the DNA synthesis and ultrastructure of human cultured endometrial stromal cells was studied. The analysis of the [3H]thymidine incorporation in the endometrial stromal cells cultured for 10 days indicated that the DNA synthesis was inhibited in a dose-dependent manner by danazol and testosterone, but not by medroxyprogesterone. The effect of 10(-7) M of danazol was blocked by cyproterone acetate, but RU-486 did not show any influence. The observation of the ultrastructure of the cultured cells revealed that 10(-7) M of danazol increased cytoplasmic lysosomes; however, 10(-5) M of danazol destroyed cell organelles and cytoskeleton resulted from the cell death. These results indicated that the biological effects of danazol were mainly mediated by androgen receptors, and 10(-5) M of danazol exhibited the toxic effect on the endometrial stromal cells.

Cells, Cultured↗

PubMed1995

Synthesis and pharmacological evaluation of 1,2,3,4-tetrahydro-beta-carboline derivatives.

A series of 1,2,3,4-tetrahydro-beta-carbolines has been synthesized and evaluated for cerebral protecting effects against lipid peroxidation and potassium cyanide intoxication in mice. Most of the compounds synthesized had potent effects against lipid peroxidation. Among them, 1-(3,5-dimethoxyphenyl)-2-propyl-1,2,3,4-tetrahydro-beta-carboline (22) was found to have a combination of potent effects against both lipid peroxidation and potassium cyanide intoxication. Structure-activity relationships are discussed.

Animals↗

PubMed1994

Synthesis and antibacterial activity of thiazolopyrazine-incorporated tetracyclic quinolone antibacterial agents. 2.

A novel series of 8-(2-substituted morpholino)-9,1-[(N-methylimino) methano]-7-fluoro-5-oxo-5H-thiazolo[3,2-a]quinoline-4-carboxylic acids, designated 8a-j, with a unique tetracyclic structure were synthesized, and the in vitro and in vivo antibacterial activities against Gram-positive strains, including methicillin-resistant Staphylococcus aureus isolates (MRSA), and Gram-negative strains were evaluated. These morpholino derivatives, 8a-j, showed excellent in vitro antibacterial activities against Gram-positive bacteria. The substitutions at the C-2 position of the 8-morpholino moiety of compound 8 play an important role in the enhancement of in vivo antibacterial activity. The unsubstituted morpholino derivative 8a, the 2,6-dimethyl derivative 8c, and the 2-ethylmorpholino derivative 8d showed poor in vivo antibacterial activity, while 8b, 8f-h, and 8j exhibited good activities. The 2-(methoxymethyl)morpholino derivative, 8h, showed the most potent activity in vivo. The therapeutic effects of 8h on systemic infection against S. aureus IID 803 were over 10-fold more potent than that of ofloxacin. Compound 8h, which showed superior oral bioavailability, has a chiral center. The enantiomers of 8h were synthesized, and the in vitro and in vivo antibacterial activities were evaluated. Both enantiomers, (S)-8h and (R)-8h, and the racemic compound 8 exhibited similar activities in vitro and in vivo. Compounds 8b and 8f-h also showed good levels of antibacterial activity against MRSA strains. The morpholino derivatives with unique tetracyclic structures are characterized by strong antibacterial activities against MRSA strains.

4-Quinolones↗

PubMed1994

Synthesis and antibacterial activity of thiazolopyrazine-incorporated tetracyclic quinolone antibacterials.

A novel series of 8-substituted-9,1-[(N-methylimino)methano]- 7-fluoro-5-oxo-5H-thiazolo[3,2-alpha]-quinoline-4-carboxylic acids 5a-q having a unique thiazolopyrazine-incorporated tetracyclic structure were synthesized, and the in vitro and in vivo activities were determined against Gram-positive and Gram-negative bacteria. All compounds 5a-q had more potent activity than ofloxacin (6), which is one of the most popular quinolones, against Gram-positive and Gram-negative bacteria. The 8-pyrrolidinyl, 5a-e, and 8-morpholino, 5p, derivatives showed the most potent activity against Gram-positive bacteria. It is also significant that these compounds, 5a-q, showed more potent antibacterial activity against methicillin-resistant Staphylococcus aureus isolates (MRSA) than ofloxacin (6). The combination of the morpholino group and this unique tetracyclic thiazolopyrazine skeleton contributes to the enhancement of the antibacterial activity against MRSA isolates. The in vivo antibacterial activities of these compounds, 5a-q, were limited and depended on the structure of the 8-substituent. The 8-(4-alkyl-1-piperazinyl) derivatives 5g, 5h, 5j, and 5n provided good oral efficacy and exhibited more potent activity than ofloxacin (6) against the systematic infection with S. aureus IID 803 in mice.

Animals↗