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T Hirayama

Publications and source records attributed to T Hirayama.

At least 163 records · Page 9Linked to original sources
PubMed1995

[Bacteriological and clinical evaluation tazobactam/piperacillin in infectious diseases in surgical field].

We carried out bacteriological and clinical studies on tazobactam/piperacillin (TAZ/PIPC), a combination drug of piperacillin with the new beta-lactamase inhibitor tazobactam, in various infectious diseases in surgical field such as intra-abdominal infections (peritonitis and intra-abdominal abscess), hepatobiliary infections (cholecystitis, cholangitis and hepatic abscess) and secondary infections in wound, etc. The total number of cases treated with the combination drug was 164. Of these cases, 141 cases were assessable for clinical responses including 60 cases with intra-abdominal infections, 38 cases with hepatobiliary infections, and 43 cases with secondary infections. Clinical efficacy rates of the drug were 83.3% in cases with intra-abdominal infections, 86.8% in cases with hepatobiliary infections, and 95.3% in those with secondary infections, hence the overall efficacy rate was 87.9%. In the cases from which beta-lactamase producing strains were isolated, clinical efficacy rates were 84.8% in cases with intra-abdominal infections, 84.6% in those with hepatobiliary infections, and 96.2% in those with secondary infections, hence the overall efficacy rate was 88.9%. Bacteriological efficacy rates were 92.9% in cases with Gram-positive bacterial infections, 64.3% in those with Gram-negative bacterial infections, and 100% in those with anaerobic bacterial infections. Bacteriological efficacy rates were 84.2% in cases with single bacterial infections and 56.5% in those with multi-bacterial infections, and the overall bacteriological efficacy rate was 69.0%. In the cases of infections with beta-lactamase producing strains, bacteriological efficacy rates were 80.0% in cases with Gram-positive bacterial infections, 75.0% in those with Gram-negative bacterial infections, and 100% in those with anaerobic bacterial infections. They were 82.6% in cases with single bacterial infections and 57.9% in those with multi-bacterial infections; the overall bacteriological efficacy rate was 67.2%. The bacterial eradication rate was 79.9% against all the isolates, and it was 79.2% against beta-lactamase producing isolates. In addition, we compared the sensitivity distribution of the isolates to TAZ/PIPC with those to control drugs piperacillin (PIPC), cefotiam (CTM), ceftazidime (CAZ), sulbactam/cefoperazone (SBT/CPZ). The MIC50 and MIC90 values of TAZ/PIPC against all strains were 3.13 micrograms/ml and 50 micrograms/ml, respectively. MIC50 values show that TAZ/PIPC was two times less effective than CAZ and SBT/CPZ but four times more effective than CTM; furthermore, from the MIC90 values, TAZ/PIPC was four times more effective than PIPC, CTM and CAZ. The MIC50 and MIC90 values of TAZ/PIPC against beta-lactamase producing strains were 3.13 micrograms/ml and 50 micrograms/ml, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Abdominal Abscess↗
PubMed1994

Cloning and sequencing of the gene encoding Vibrio cholerae O1 fimbrial subunit (fimbrillin).

The gene encoding an 18 kDa fimbrial subunit of Vibrio cholerae O1 was identified in a fimbriate strain Bgd17. Mixed oligoprimers were prepared based on the amino acid sequence of the N-terminus and that from a cyanogen bromide-cleaved fragment of the fimbrillin. A PCR-amplified 185 bp DNA fragment was sequenced. This 185 bp fragment was further extended to 540 bp to 3' and 5' termini by RNA-PCR using a primer containing a random hexamer at its 3' end. This fragment did not contain the stop codons. It was further extended by a gene walking method using Eco RI cassette and its primers. Finally a 660 bp fragment was obtained and sequenced. This fragment contained the complete open reading frame of the structural subunit of the fimbriae, composed of 169 amino acids with a molecular mass of 17435.65 and a leader sequence of 6 or 9 amino acids. The deduced amino acid sequence of the polypeptide encoded by the gene, designated fimA, displayed a highly conserved sequence of MKXXXGFTLI EL of type 4 fimbriae.

Amino Acid Sequence↗
PubMed1994

Assessment of sister chromatid exchange in mouse embryos produced by microsurgical fertilization.

The treatment of male factor-related infertility has been approached with the advent of several methods for microsurgical fertilization, such as the partial dissection of the zona pellucida (PZD) and the injection of sperm into the perivitelline space (PVSI) of oocytes. These techniques are designed to increase sperm-oolemma interaction by circumventing passage of the sperm through the zona pellucida. The present study was performed to evaluate the influence of PZD and PVSI on the in vitro development of mouse embryos by assessing the rate of sister chromatid exchange (SCE). SCE is considered to be a sensitive indirect indicator of DNA lesions due to various conditions. Oocytes were cultured in vitro after PZD or PVSI and then examined for SCE. There was no significant difference in SCE between control and treatment groups of embryos and the values were similar to those reported by Saito et al. (Fertil Steril 41:460-464, 1984). The rate of SCE was low during the first two mitotic cycles, then increased from cycle two to three before declining slightly between the 3rd and 4th cycles of cell division. These data demonstrate that the direct interaction of sperm and oocyte by PZD or PVSI did not have an adverse effect on the development of mouse embryos as assessed by the rate of SCE.

Animals↗
PubMed1994

Attenuation of hemispheric swelling associated with acute subdural hematomas by excitatory amino acid antagonist in rats.

Acute subdural hematoma (ASDH) gives rise to a mass effect not only by itself but also through unilateral hemispheric swelling. The present study tested the hypothesis that hemispheric swelling is mediated by mechanisms which involve excitatory amino acids (EAAs). After removal of the subdural clot, introduced by homologous blood (0.1-0.2 ml), the % brain water was determined from the formula: ((wet weight--dry weight)/wet weight) x 100. The % brain water of the left hemisphere was significantly greater than that of the right hemisphere during the initial 6 hours after induction of ASDH in animals injected with 0.2 ml blood. A less marked but significant increase was observed in the animals injected with 0.1 ml blood. Systemic pretreatment with kynurenic acid (KYN; 800 mg/kg, i.p.), a broad-spectrum EAA antagonist, attenuated the increase in % brain water in the animals injected with 0.2 ml blood. In order to determine the changes in cerebral metabolism induced by the model of ASDH employed in the present study, we measured the cortical cytochrome oxidase (CYO) activity, a marker of mitochondrial respiration, in a separate group of animals. The CYO activity estimated densitometrically from the histochemical staining was not significantly altered in the animals injected with either 0.1 or 0.2 ml blood, suggesting absence of ischemia. These results indicated that the hemispheric swelling associated with thin ASDHs may be partially mediated by mechanisms other than ischemia, in which EAAs appear to be involved.

Animals↗
PubMed1994

Systemic management of cerebral edema based on a new concept in severe head injury patients.

Cerebral hypothermia treatment of critical brain injury patients was studied based on the management and control of cerebral thermo-pooling, synaptic excitation, hypermetabolic demand, and the systemic critical condition of the metabolic reserve. The initial pathophysiological changes after trauma included a progressive increase in brain tissue temperature. Such cerebral thermo-pooling, which reached a maximum of 43.8 degrees C, can change or damage the vascular proteins directly. The brain tissue temperature was influenced by four factors: 1. the cerebral metabolism, 2. the systemic excess energy metabolism, 3. the CPP that carries the systemic energy to the brain tissue, and 4. the cerebral blood flow that leads to washout of brain tissue temperature. Mild cerebral hypothermia (32-33 degrees C) managed by the whole body compartment cooling technique in the critical conditions of diffuse brain injury patients (GCS < 4) produced a good recovery in 8 of 10 patients. Continuous monitoring of the jugular venous oxygen saturation and BTT/TMT was effective for evaluating cerebral ischemia and oxygen metabolic disturbances even during cerebral hypothermia treatment.

Blood-Brain Barrier↗
PubMed1994

Metabolic activation of nitrodibenzofurans by rat liver in Salmonella/mutagenicity test.

The effect of metabolic activation on the mutagenicity of nitrodibenzofurans (NDF) by rat liver S9 was evaluated with S. typhimurium tester strains. Except for 1-nitrodibenzofuran (NDF), five tested NDFs were mutagenic in strains TA98 and TA98/1,8-DNP6 without S9 mix but were not mutagenic in strain TA98NR. NDFs mutagenized strain TA98NR with S9 mix, and the NAD(P)H system plus 3-methylcholanthrene-induced S9 (3-MC-S9) was the most effective. The specificity of S9 enzyme(s) participating in the activation of NDFs was different from that of endogenous enzyme(s) in strain TA98, i.e., the order of mutagenic potency of NDFs in strain TA98 without S9 mix was 2,8- = 2,7-->3-->2-->4-->1-nitrated dibenzofuran and 2-NDF and 2,8-dinitrodibenzofuran (DNDF) were more mutagenic than 3-NDF and 2,7-DNDF, respectively, in strain TA98NR with S9 mix. The mutagenic potency of 2-NDF, 4-NDF, 2,7-DNDF and 2,8-DNDF in strain TA98NR with S9 mix was stronger than those in strain TA98 without S9 mix and the cytosolic fraction of the 3-MC-S9 accounted for more of the activation than the microsomal fraction. Studies with electron donors and inhibitors indicated that xanthine oxidase and/or NAD(P)H-quinone oxido-reductase (NQOR) participated in the activation of NDFs. The mutagenic potency of NDFs in strain TA98NR with S9 mix (3-MC-S9) was reflected in the induction of NQOR by pretreatment of rats with 3-MC.

Animals↗
PubMed1994

Control of systemic hypertension with diltiazem, a calcium-antagonist, in patients with a mildly elevated intracranial pressure: a comparative study.

A cerebral vasodilatory action could represent a critical adverse effect of any drug used to control the systemic blood pressure (SBP) in patients with an elevated intracranial pressure (ICP), since such an action increases the ICP and thereby reduces the cerebral perfusion pressure (CPP). While several new calcium antagonists are now available, each drug exerts variable dilatory actions on the cerebral, coronary and peripheral vasculatures. Among these agents, diltiazem has been found to be sufficiently potent to control systemic hypertension but to have a less potent dilatory action on the cerebral vasculature in experimental animals. Based on such a characteristic, diltiazem appears to be an ideal drug for controlling systemic hypertension in patients with an elevated ICP. However, little has yet been investigated in the clinical setting. In the present study, the effects of three drugs, i.e., nitroglycerin, nicardipine and diltiazem, on the ICP were analysed retrospectively. Data were collected from patients who had demonstrated a mildly elevated ICP (mean ICP, 10-23 mmHg) and moderate systemic hypertension (mean SBP, 97-125 mmHg) during the period of 72 hours after surgical evacuation of spontaneous intracerebral haematomas. We reviewed the computer-based records of 385 patients, and identified 35 episodes in which the mean SBP was reduced by more than 10 mmHg by one of these three drugs alone during the initial 24 hours after haematoma evacuation.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Pig intestinal membrane-bound receptor (guanylyl cyclase) for heat-stable enterotoxin: cDNA cloning, functional expression, and characterization.

A cDNA encoding the receptor protein for a heat-stable enterotoxin (STa) produced by enterotoxigenic Escherichia coli was cloned from intestinal epithelial cells of a 10-week-old pig. The cDNA had an open reading frame of 3,219 base pairs and coded for a protein with 1,073 amino acid residues. The mature protein consisted of 1,050 amino acid residues with a molecular mass of ca. 121 kDa and was 87% and 82% identical with the human and rat protein, respectively. The CHO cell line overexpressing the pig recombinant STa receptor specifically bound to a photoaffinity-labeled analog of STa and showed marked elevation of the cellular content of cGMP in response to STa.

Amino Acid Sequence↗
PubMed1994

A girl having congenital chloride diarrhea treated with spironolactone for seven years.

We report on a girl having congenital chloride diarrhea (CCD) who has been followed for 7 years and 6 months sequentially. Dilated intestinal loops, marked enlargement of the abdominal circumference of the fetus and hydramnios were noted by ultrasound examination at 31 weeks of gestation. After delivery by cesarean section for hydramnios, she excreted profuse watery yellow green stools with marked abdominal distension. At 4 months of age, hypochloremia, hyponatremia and a high concentration of chloride in the stool were identified. She was diagnosed as having CCD. Because it was difficult to administer a large volume of potassium chloride (KCl), and sodium chloride (NaCl), we decided to administer spironolactone. After administration of spironolactone, we could generate correct serum electrolytes using less amounts of KCl. At 7 years and 6 months of age, her body size was within normal limits and her intellectual, mental and physical development had been normal. In spite of normal serum electrolytes, blood pH and the presence of chloriduria, secondary hyperaldosteronism was noted. We consider that spironolactone may be useful to decrease the amount of KCl administration in the neonatal period, but frequent measurements of renin, angiotensin and aldosterone would be necessary for adequate control in CCD cases.

Child↗
PubMed1994

A Ro/SS-A auto-antibody positive mother's infant revealed congenital complete atrioventricular block, followed by insulin dependent diabetes mellitus and multiple organ failure.

We experienced a congenital complete atrioventricular block infant who was born from a Ro/SS-A antibody positive mother. Ro/SS-A antibody was also found in this baby which was presumed to be mediated by the maternal placenta. Temporary cardiac pacing was required at birth and pacemaker implantation was performed at 9 months. At 11 months of age, the baby fell into shock and experienced multiple organ failure because of diabetes mellitus-induced coma. The association between congenital complete heart block and the Ro/SS-A antibody is well known. However, the accompaniment of insulin-dependent diabetes mellitus has not been reported previously. As the Ro/SS-A antigen appears in the cytoplasm of many tissues, the possibility of an association between Ro/SS-A antibody and diabetes mellitus is difficult to deny. We report this rare case to draw attention to the possibility that babies who are born from an Ro/SS-A antibody positive mother may develop diabetes mellitus as well as congenital complete heart block.

Adult↗
PubMed1994

Comparative study of five types of IABP balloons in terms of incidence of balloon rupture and other complications: a multi-institutional study.

The Multi-Institutional IABP Balloon Study Group in Japan (14 institutions) conducted a retrospective nonrandomized study to elucidate the incidence and type of IABP balloon-related complications relative to design and durability of five different clinically available balloons: TMP (n = 960), Kontron (n = 943). Datascope (n = 485), Mansfield (n = 226), and Aries (n = 189) balloons. A total of 2,803 patients (1,973 males, 830 females, mean age 62.1 years) spent a total of 243,856 h on the pump. Forty-nine balloons (1.7%) ruptured as recognized by the appearance of blood in the catheter (39 cases) or console alarm (4 cases). Ten patients required surgical removal of the balloon due to entrapment. Other IABP balloon-related complications requiring surgical intervention or with a lethal outcome occurred in 89 patients (3.2%). They included lower limb ischemia (61 cases), hematoma (11 cases), extensive dissection (6 cases), perforation (5 cases), entrapment without balloon rupture (3 cases), and mesenteric infarction (3 cases). The incidence of rupture, other major complications, and total complications, respectively, for each balloon was 0, 2.7, and 2.7 for TMP, 1.6, 4.3, and 5.9% for Kontron, 4.1, 1.9, and 6.0% for Datascope, 1.3, 2.7, and 4.0% for Mansfield, and 5.8, 3.7, and 9.5% for Aries. In conclusion, the TMP balloon demonstrates a significantly lower rate of rupture while the incidence of other complications for the 5 balloons is not significantly different.

Equipment Failure↗
PubMed1994

Muscle strength and fall rates among residents of Japanese and American nursing homes: an International Cross-Cultural Study.

OBJECTIVE: In Western society, aging if often associated with adoption of a sedentary lifestyle and associated disuse muscle atrophy and weakness. Recent studies suggest a relationship between quadriceps muscle weakness and falls in elderly residents of US nursing homes (NHs). We hypothesized that fall rates would be lower in Japanese NHs, where lifestyle differences such as squatting to toilet or sleeping on the floor may maintain quadriceps strength and result in fewer falls. Therefore, we examined the relationships between falls, muscle strength, lifestyle, and other clinical characteristics in residents of a Japanese and an American NH. DESIGN: Cross-culture, prospective, cohort study. MEASUREMENTS: We evaluated disease histories and current medications, quadriceps strength, and mobility of ambulatory American (n = 76) and Japanese (n = 89) NH residents, then followed these residents prospectively for the development of falls. Project staff from both sites trained together to assure uniform data ascertainment. MAIN RESULTS: During a 6-month follow-up period, fall rates were nearly 4-fold higher in the American than in the Japanese residents (49% vs 13%, respectively; P < 0.0001). In the American sample, fall rates declined with increasing muscle strength, while in Japan there was no relationship between fall rates and quadriceps strength. Residents also differed in number of medical diagnoses and use of medications, which were greater among American residents. The Japanese had slower gait speeds. Very few Japanese residents practiced squatting behaviors while living in the NH. CONCLUSIONS: The relationship between muscle weakness and falls is probably modified by multiple characteristics of the individual, their culture, and their environment. Information from cross-cultural studies may provide new insights into effective fall prevention strategies for nursing home residents.

Accidental Falls↗
PubMed1994

Early detection of anthracycline cardiotoxicity in children with acute leukemia using exercise-based echocardiography and Doppler echocardiography.

We performed both supine bicycle ergometer (BEx) and hand-grip (HGx) exercise tests to evaluate cardiac function in 13 asymptomatic children with leukemia who had completed a general treatment protocol. We calculated fractional shortening (FS), end-systolic stress-volume index (ESS/ESVI), left ventricular diastolic filing velocity ratio (A/E) and normalized peak rate of diastolic increase in left ventricular internal dimension (dLVDt/dt/LVDt). Before the exercise, we found that dLVDt/dt/LVDt was decreased in the high-dose anthracycline group (anthracycline cumulative dose of 480-570 mg/m2), even though other cardiac function parameters were not different from those in the control. In BEx, the percent change in ESS/ESVI decreased in an anthracycline cumulative dose-dependent fashion. In HGx, ESS/ESVI showed a decreased response only in the high-dose anthracycline group. Therefore, we conclude that: 1) the diastolic function parameter dLVDt/dt/LVDt might show abnormalities prior to other systolic function parameters, 2) the percent change in ESS/ESVI in BEx is the most sensitive parameter studied, and could detect cardiac function abnormalities even in the small-dose anthracycline group (anthracycline cumulative dose of 175 mg/m2), and 3) BEx is more suitable for the early detection of anthracycline cardiotoxicity than HGx.

Acute Disease↗
PubMed1994

[Noninvasive evaluation of chronic cumulative and acute cardiotoxicity induced by anthracycline in children with acute leukemia. Assessment of mainly left ventricular contractile state by M mode echocardiography].

The cardiotoxic effects of Daunomycin (DM) ad Adriamycin (ADR), Anthracyclines (ATC), were studied mainly by echocardiography to evaluate their chronic cumulative cardiotoxicity and acute cardiotoxicity during consolidation therapy. Electrocardiographic findings were less sensitive and therefore less reliable for evaluation of the chronic cumulative cardiotoxicity and acute cardiotoxicity induced by ATCs during consolidation therapy. With echocardiography ESS/ESVI, the index of the left ventricular contraction, had the highest sensitivity among indices for cardiotoxicity. SF was useful for easy measurement and calculation of cardiotoxicity. Evaluation of the chronic cumulative cardiotoxicity of ATC drugs indicated that cumulative doses of 300 mg/m2 or more resulted in abnormally low ESS/ESVI levels suggesting cardiotoxicity in many cases, and doses of 500 mg/m2 or more caused abnormally low levels in all cases. Evaluation of acute cardiotoxicity showed that post-consolidation therapy ESS/ESVI levels were significantly lower than pre-consolidation therapy levels in the group treated with doses of 500 mg/m2 or more, but the condition was reversible except in those patients with heart failure. As for the relation between cumulative doses and cardiotoxicity, the indices studied showed no differences between DM and ADR. These results indicate that careful follow-up mainly by echocardiography is required after doses reaching 300 mg/m2 or more of ATC drugs.

Adolescent↗
PubMed1994

[Echocardiographic evaluation of left ventricular hemodynamics in children with post-streptococcal acute glomerulonephritis].

Left ventricular hemodynamics were studied using M-mode and pulsed doppler echocardiography in 18 cases with post-streptococcal acute glomerulonephritis (PSAGN) during the acute phase. Both the ratio of left atrial to aortic dimension and the end-diastolic volume index increased in the acute phase compared with those in the recovery phase in each case (p < 0.01, p < 0.01). These results indicated that the increase in the preload was due to hypervolemia. End-systolic wall stress increased in the acute phase (p < 0.01), thereby the afterload was considered to have increased as well. But the value of systemic vascular resistance showed no significant difference in either phase. Therefore it seems the increase of the afterload was due to increasing blood pressure, which was mainly due to hypervolemia. The ratio of end-systolic wall stress to the end-systolic volume index (ESWS/ESVI) was significantly higher in the acute phase (p < 0.01). Stroke volume index (SI) was also increased in the acute phase (p < 0.01). The increase in SI was considered to be due to a more prominent increase in both the preload and left ventricular contractility than in the afterload. Left ventricular inflow patterns derived from pulsed doppler echocardiography also suggested a markedly increased preload and an increased afterload in the acute phase. These data showed that in the acute phase of PSAGN, left ventricular preload, contractility and afterload were increased due mainly to hypervolemia.

Acute Disease↗
PubMed1994

[Estimation of localization of the accessory pathway in WPW syndrome with a standard 12 lead electrocardiogram. Development of new criteria for children].

In 128 children with WPW syndrome, localization estimation was based on the accessory pathway (ACP) localization criteria of the standard 12 lead electrocardiogram for adults proposed by Gallagher et al., Iwa et al., Lindsay et al., and Reddy et al. The rate of consistency of each set of criteria with body surface mapping (BSM) (based on the criteria of Kamakura et al.) was examined along with evaluation of reliability. Among the localization criteria, the most reliable set for children was that developed by Iwa et al. The addition of the precordial lead QRS transitional zone to the criteria established by Iwa et al. was proposed as a means of making the criteria were appropriate for children with WPW syndrome. The consistency rate of localization with this new criterion was added with the results of BSM reached 93% including interpolations. Thus this new localization criterion was considered effective for the estimation of ACP localization in children with WPW syndrome.

Adolescent↗