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Biomedical subjects

S Hirata

Publications and source records attributed to S Hirata.

At least 73 records · Page 4Linked to original sources
PubMed1999

[A case of tracheal fistula after operation for esophageal cancer].

We have experienced a case of mediastinal abscess and tracheal fistula after operation for esophageal cancer and successfully closed by using intercostal muscle pedicle flap. A 61-year-old male underwent esophagectomy for advanced esophageal cancer. On the 12th postoperative day, mediastinal abscess caused by leakage was detected, and drainage of the mediastinal and thoracic cavity was performed. On the 29th postoperative day, tracheal fistula was detected, and operation was performed in order to close the fistula by using of intercostal muscle pedicle flap. His postoperative course was fair and general condition was improvement, esophageal reconstruction using of free jejunal graft was performed and oral ingestion was started.

Aged↗
PubMed1999

[Oral and dental health and oral and dental support of home patients--role of dental hygienist in the home service nursing station].

Home patients have few chances for going out, so communication with their family means a lot. Talking and eating are particular pleasures. Therefore, oral and dental health and oral and dental support are very important for home patients. A dental hygienist from our clinic visits and offers oral and dental health (oral care) and oral and dental support (oral rehabilitation) to home patients as part of a care plan with home care nurses. Moreover, as general conditions are closely related with oral function, maintaining oral and dental health and regular oral and dental support are very important in order to improve the quality of life (QOL) of home patients.

Aged↗
PubMed1998

Vascular endothelial growth factor inhibits apoptotic death in hematopoietic cells after exposure to chemotherapeutic drugs by inducing MCL1 acting as an antiapoptotic factor.

We reported previously that vascular endothelial growth factor (VEGF) inhibits the apoptotic death of hematopoietic cells that is induced by exposure to ionizing radiation (O. Katoh et al., Cancer Res., 55: 5687-5692, 1995). In this study, we show that VEGF also inhibits apoptotic cell death that is induced by exposure to the chemotherapeutic drugs etoposide and doxorubicin. To elucidate the molecular mechanisms underlying this inhibitory effect of VEGF, we examined expression levels of BCL2 family proteins in CMK86, a human leukemia cell line, after treatment with VEGF. Northern blotting and immunoblotting analyses revealed that the expression level of MCL1, a member of the BCL2 family, was increased by VEGF. Moreover, to examine the effects of MCL1 on apoptotic cell death induced by exposure to etoposide, we generated a clonal U937 myeloid leukemia cell line transfected with vectors that promoted the constitutive expression of MCL1. MCL1 decreased the caspase 3 activity induced by exposure to etoposide and increased the viability of the transfected cells after etoposide exposure. Therefore, MCL1 may be involved in the inhibitory effect of VEGF on apoptotic cell death.

Antineoplastic Agents↗
PubMed1998

The Krüppel-type zinc finger family gene, HKR1, is induced in lung cancer by exposure to platinum drugs.

To investigate the molecular mechanism associated with the signaling pathway of platinum drug administration, we focused on the C2H2-type zinc finger (ZNF) transcription factor gene family. Here we show cloning of a Krüppel-type ZNF gene, HKR1, which contains Krüppel-associated box (KRAB) domain and ZNF motifs. We found that mRNA expression of the HKR1 gene was induced in lung-cancer cell lines by exposure to cisplatin using Northern blot analysis. Moreover, we also found that HKR1 mRNA expression levels in lung cancers were higher than those in normal lung tissues, and that high expression levels in lung cancers were associated with antemortem platinum drug administration. These results suggest that HKR1 may be associated with the regulation of a signaling pathway involved in the progression of lung cancer or the acquisition of resistance to platinum drugs.

Adenocarcinoma↗
PubMed1998

Use of leaves as cushions to sit on wet ground by wild chimpanzees.

A new type of tool use, leaf cushion, by wild chimpanzees (Pan troglodytes verus) at Bossou, Guinea, was found. We report two cases: one is indirect evidence; the other is direct observation of a chimpanzee who used the tool. Both cases indicate that chimpanzees used a set of leaves as a cushion while sitting on wet ground. Chimpanzees at Bossou show various kinds of tool use, some of which are unique to the community. Most of these behavioral patterns are substance tool use for obtaining food, as at other study sites. The use of leaves as a cushion adds to the few instances of nonsubstance, elementary technology seen used by wild chimpanzees.

Animals↗
PubMed1998

Sequential changes in cardiac structure and function in patients with Duchenne type muscular dystrophy: a two-dimensional echocardiographic study.

BACKGROUND: Most patients with progressive muscular dystrophy of the Duchenne type (DMD) die of respiratory failure at approximately 20 years of age. However, some patients with DMD die of heart failure in relatively short periods of time. We investigated the long-term progression of cardiac impairment in patients with DMD by two-dimensional echocardiography. METHODS: We monitored 74 patients for 4 years with two-dimensional echocardiography. Patients were classified into four groups according to the 8-grade Swinyard-Dever system. We also evaluated the echocardiographic features of 22 other patients with DMD with studies performed within 1 year before their deaths. RESULTS: During the 4-year follow-up the left ventricle expanded, and regional left ventricular wall motion abnormalities developed in the posterior wall and apex. Almost all patients had myocardial dysfunction that progressed in parallel with their Swinyard-Dever stage. However, in a few patients who died of congestive heart failure, left ventricular dilation and circumferential left ventricular wall motion were severely impaired. CONCLUSIONS: Myocardial impairment is accelerated in patients with DMD who died of heart failure. Two-dimensional echocardiography is a useful tool for the early diagnosis of left ventricular dysfunction and provides useful information for the treatment of patients with DMD.

Adult↗
PubMed1998

The multiple untranslated first exons and promoters system of the oestrogen receptor gene in the brain and peripheral tissues of the rat and monkey and the developing rat cerebral cortex.

Recent studies on the human oestrogen receptor (ER) gene have revealed the complex system with the multiple untranslated first exons and promoters in the ER gene expression. Little information is however available on the system in the ER gene of the rat or nonhuman primate. The rat genomic library was first screened by the rat ER cDNA (0-1) probe. One of the four positive clones (lambda rEgE1) was subcloned and sequenced. The nucleotide sequence was found to contain the exon 0, the intron 0, and the exon 1 with its 3'-ends. The novel untranslated first exons, the exon ON and the exon OS, were further identified. These results indicated the presence of at least four subtypes of the rat ER mRNAs; the messages transcribed from promoter P-0 (ER mRNA (0-1)), putative promoter P-1 (ER mRNA (1-1)), promoter P-ON (ER mRNA (ON-1)) and promoter P-OS (ER mRNA (OS-1)). The P-O- or P-1 driven message (0-1) or (1-1) appeared to be expressed most strongly in major oestrogen central- (anterior pituitary, AP, hypothalamus-preoptic area, HPOA, and amygdala, AMG) and peripheral targets (uterus and ovary). The message (ON-1) was strongly expressed in the liver and kidney, but not in the HPOA, AMG, cerebral cortex, CC, and cerebellum, Ce. The OS-1 message was expressed variably but generally in the tissues examined except for the CC and Ce. Thus, the region- and tissue specific expression of the rat ER gene is likely to be regulated by the multiple untranslated exons and promoters system. Furthermore, when the ER mRNA subtypes were examined in the rat neonatal CC where the ER protein level rose transiently, considered as a model for the development of the ER or progestin receptor A and B isoforms, the expression of the ER mRNAs seemed to be differential postnatally, implicating some stage dependent usage of the promoters in the development. In the monkey, we identified the untranslated first exon OS, the homologue of the rat exon OS. Interestingly, the exon C was found to consist of two different exons, the exon OK and the exon OG. By the alternative usage of the promoters and the alternative splicing, at least six ER mRNA subtypes, that is, ER mRNAs (0-1), (1-1), (OS-1), (OS-OG-1), (OK-1) and (OK-OG-1) were identified in the monkey tissues. These messages were also differentially distributed in the monkey brain and other tissues. It was noteworthy that the P-OK driven messages were expressed almost exclusively in the monkey liver. These results have suggested that the systems of the multiple untranslated first exons and promoters and the alternative splicing are involved in the regulation of the region- and tissue specific expression of the ER gene in the brain and peripheral tissues of the rat and monkey. Stage-related usage of the promoters was also suggested in the ER gene expression in the CC of the postnatal rat in development.

Amino Acid Sequence↗
PubMed1998

Difference in incidence and transmission mode of methicillin-resistant Staphylococcus aureus among surgery, orthopedics, and pediatrics wards: a prospective study at a university hospital.

The incidence and circumstances of colonization by methicillin-resistant Staphylococcus aureus were prospectively investigated. Among 404 patients, 15 (3.7%) were carriers on admission, and 43 (10.6%) became colonized, mainly after surgical operation. A different mode of transmission was suggested in each ward.

Adult↗
PubMed1998

Effects of isoflurane on receptor-operated Ca2+ channels in rat aortic smooth muscle.

We have investigated the effects of isoflurane on receptor-operated Ca2+ channels (ROC) in vascular smooth muscle. In isolated rat thoracic aortic rings denuded of endothelium, the effects of isoflurane on phenylephrine-induced contraction and Ca2+ influx were evaluated in the presence of supramaximal doses of nifedipine or verapamil. Under isometric tension recording, the aortic rings were precontracted by phenylephrine 300 nmol litre-1 and exposed to 1.2%, 2.3% or 3.5% isoflurane. Phenylephrine-induced precontraction was enhanced with 2.3% isoflurane by mean 8.1 (SD 9.3)% (P < 0.05 vs 0% isoflurane). The constrictor effect of 2.3% isoflurane was not inhibited by depletion of intracellular Ca2+ stores with ryanodine 20 mumol litre-1, but was abolished in a Ca(2+)-free solution or by SK&F 96,365 30 mumol litre-1, an ROC blocker. Isoflurane-induced contraction was accompanied by increased intracellular free Ca2+ concentration, monitored using fura PE3. Unidirectional 45Ca2+ influx measurement in phenylephrine-stimulated aortic strips revealed that the mean amount of Ca2+ influx was significantly (P < 0.05) enhanced by 1.2% and 2.3% isoflurane, which were 117.1% and 119.7% of control values, respectively. Our results strongly suggest that isoflurane enhanced Ca2+ influx through ROC that had been submaximally activated by phenylephrine.

Anesthetics, Inhalation↗
PubMed1998

Thiopental attenuates relaxation and cyclic GMP production in vascular smooth muscle of endotoxin-treated rat aorta, independent of nitric oxide production.

As thiopental (thiopentone) suppresses cyclic GMP (cGMP) formation produced by nitric oxide donor drugs, we have tested if it suppresses cGMP formation and increases vascular tone after induction of calcium-calmodulin-independent nitric oxide synthase (iNOS). Rat aortic rings were treated with Escherichia coli lipopolysaccharide (LPS) 1 microgram ml-1 for 4 h, and the effects of thiopental on tension, cGMP concentrations and nitrite accumulation were determined. Thiopental 0.3 mmol litre-1 reduced the tension of phenylephrine-precontracted aortic rings before LPS treatment, but caused no significant effects on tension in the presence of L-arginine 10 mumol litre-1 after LPS treatment. L-Arginine 1 mumol litre-1 to 1 mmol litre-1 increased concentrations of cGMP in LPS-treated aorta in a concentration-dependent manner. This was reduced by thiopental 0.3-1 mmol litre-1. Treatment with L-arginine 1 mmol litre-1 increased concentrations of nitrite, the end product of nitric oxide; this was not affected by thiopental 1 mmol litre-1. We conclude that thiopental suppressed cGMP formation in iNOS-induced vascular smooth muscle without affecting nitric oxide production.

Anesthetics, Intravenous↗
PubMed1998

[Decongesting effect of tramazoline on nasal airway patency and nasal symptoms as evaluated by acoustic rhinometry: an objective study in 30 allergic and six non-allergic subjects].

In this prospective clinical study, we investigated the effect of the nasal decongestant tramazoline on nasal airway patency in 30 subjects with perennial nasal allergy to housedust mites and in six non-allergic volunteers who served as controls. The allergic subjects were further subdivided into groups, the severe group and the moderate group, according to the level of specific IgE. We used acoustic rhinometry as an objective method, and the nasal cavity volume (NCV) and the minimum cross-sectional area (MCA) were measured before and 10 minutes after nasal spraying. Before mucosal decongestion, the average NCV in the severe group was 5.94 cm3, which was significantly lower than those in the other two groups: 7 cm3 in the control group and 8.13 cm3 in the moderate group, respectively (P = 0.02). A more significant difference was found when the first 3-cm area of the NCV was evaluated (P = 0.009). Pharmacologic decongestion caused an increase in nasal patency by 54% from the baseline NCV values in the control group, 38% in the moderate group and 48% in the severe group. There was no significant difference among the three groups. Changes in nasal symptoms were also determined by questionnaire. The degree of improvement in subjective nasal congestion was more pronounced in the allergic groups than in the control group.

Acoustics↗
PubMed1998

[Intraoperative coronary artery spasm treated by percutaneous cardiopulmonary support in a patient with left lung cancer].

A 53-year-old man with left lung cancer underwent left upper lobectomy and extended mediastinal lymphadenectomy. Shortly before the end of the operation, electrocardiogram showed elevation of ST wave and multiple ventricular premature contractures first, then ventricular fibrillations, and finally cardiac arrest. Coronary artery spasm was strongly suspected. The patient was resuscitated by cardiac massage and countershock immediately, however, such attacks repeated several times. As medication and cardiac pacing were not effective, percutaneous cardiopulmonary support (PCPS) was established. The hemodynamics was stabilized with PCPS. He was weaned off PCPS the next day. He was discharged and has had no attack so far. PCPS is an excellent modality for intraoperative coronary spasm which is uncontrollable by medicines and other methods.

Carcinoma, Squamous Cell↗
PubMed1998

[Epidemiological study of allergic rhinitis in different districts].

We investigated the morbidity of allergic rhinitis in downtown, rural area and fishing village by questionnaire in October, 1996. The morbidity rate of allergic rhinitis was 35.7% (370 subjects out of 1036) in downtown, 27.5% (266 out of 966) in rural area and 12.9% (273 out of 2112) in fishing village, and that of adult was 36.2% (314 out of 868) downtown, 28.9% (137 out of 474) in rural area and 12.07% (199 out of 1649) in fishing village, and that of child was 33.3% (56 out of 168) in downtown, 26.22% (129 out of 492) in rural area and 15.98% (74 out of 463) in fishing village. The morbidity of Japanese cedar pollinosis was 17.37% (180 out of 1036) in downtown, 13.77% (133 out of 966) in rural area and 2.60% (55 out of 2112) in fishing village. There was statistical difference (p < 0.001) between the each district respectively. It was proved that the morbidity of allergic rhinitis in downtown was higher than the rural area or fishing village, and that in fishing village was the lowest in these districts.

Adolescent↗
PubMed1997

Prognostic value of Doppler transmitral flow velocity patterns in acute myocardial infarction.

Doppler transmitral flow patterns are partially dependent on age. We investigated the correlations between the age-adjusted transmitral flow patterns, hemodynamic indexes, and the coronary and clinical outcome in 206 patients with acute myocardial infarction (AMI) and 102 normal control subjects. The peak flow velocity at atrial contraction was significantly lower in 50 of the 206 patients (24%) (low-A group) than in the 102 normal controls. Pulmonary capillary wedge pressure was significantly higher in the low-A group than in the remaining 156 patients with AMI (20 +/- 7 vs 11 +/- 5 mm Hg, p <0.001), and the cardiac index and left ventricular ejection fraction were significantly lower (2.2 +/- 0.6 vs 2.9 +/- 0.7 L/min/m2, p <0.001; 38 +/- 15% vs 52 +/- 13%, p <0.001). The incidence of cardiogenic shock was significantly higher in the low-A group than in the other patients with AMI (42% vs 19%, p <0.001). Regression analysis demonstrated a significant association between decreased atrial filling velocity and increased in-hospital mortality as well as the incidence of heart failure in AMI (p <0.001). The 5-year mortality rate was also significantly higher in the low-A group (p <0.001). The age-adjusted transmitral flow pattern in AMI can identify patients with left ventricular dysfunction, which can lead to a poor prognosis.

Adult↗
PubMed1997

Mirizzi syndrome caused by xanthogranulomatous cholecystitis: report of a case.

Xanthogranulomatous cholecystitis (XGC) is a rare inflammatory disease of the gallbladder. In severe cases, inflammation extends to adjacent structures, and XGC is sometimes confused with a malignant neoplasm. We recently diagnosed XGC as the preoperative cause of Mirizzi syndrome in a patient based on the clinical course. The patient was admitted because of obstructive jaundice, with gallbladder carcinoma as the suspected cause. The gallbladder was swollen with gallstones and the serum level of carbohydrate antigen 19-9 (CA19-9) was 3070 U/ml at admission. A percutaneous transhepatic cholangiodrainage (PTCD) was done, and the common hepatic duct as well as the right and left hepatic ducts were found to be obstructed. Later, the CA19-9 level and swelling of the gallbladder decreased and the obstruction of the bile ducts disappeared. A cholecystectomy was performed and the intraoperative pathohistological diagnosis of chronic cholecystitis was made from frozen sections. The pathohistological diagnosis of XGC was made from paraffin-embedded sections. Mirizzi syndrome such as that seen in our patient is a rare complication of XGC. XGC occasionally causes extensive inflammation; thus, performing a conventional cholecystectomy can be unsafe. However, in our opinion, a total, not subtotal, cholecystectomy should be done whenever possible because the incidence of gallbladder carcinoma accompanied with XGC is higher than that with ordinary cholecystitis or gallstones.

CA-19-9 Antigen↗
PubMed1997

Studies on dynamic behavior of the biosensor based on immobilized glucoamylase-glucose oxidase membrane.

Frequency response of the glucose/maltose biosensors based on immobilized glucoamylase and glucose oxidase membranes of different thickness were investigated with the sinusoidal signal generator of substrate concentration. The results were modeled by the serial combination of the dead time and the first order response blocks, and time constants and dead times were estimated. The estimated value of time constant ranged from 4.5 to 13.2 s and that of the dead time from 3.2 to 7.7 s with the tendency that both time constant and dead time increase as membrane thickness increases and number of enzymatic reaction steps increases.

Biosensing Techniques↗
PubMed1997

Expression and distribution of cortical type aromatase mRNA variant in the adult rat brain.

Our previous study showed that a relatively high level of the aromatase mRNA existed in the cerebral cortex (CC) of the rat, where the aromatase activity was reported to be little or absent. To elucidate the identity of the aromatase mRNA in the CC of the rat, we investigated the 5'-region of the aromatase mRNA in the rat CC. When the sequence of the 5'-region of the cortical message was analysed by the 5'-rapid amplification of cDNA ends (5'-RACE) with the antisense primer for exon II using the RNA extracted from the CC, no clone could be isolated. However, the upstream sequence from the 5'-end of exon IV of the aromatase clones, isolated from the CC by RACE with the antisense primers for exon V, was different from that on the aromatase mRNA encoding the full translated region. The new sequence of the cortical type message, called the cortical type aromatase mRNA variant, was located on the intron upstream of exon IV in the genomic cDNA. Distribution of the brain aromatase message with exons III-V and the cortical type aromatase mRNA variant were analysed by the reverse transcription-polymerase chain reaction (RT-PCR) using total RNAs extracted from the hypothalamus-preoptic area (HPOA), amygdala (AMY) and CC. The PCR products with primers for exons III-V were generated from the HPOA and AMY, but not from the CC. On the other hand, the PCR products with primers for exon IIIv (cortical type aromatase mRNA variant specific)-V were detected in significant amounts in the CC as well as the HPOA and AMY. These results indicate the existence of the aromatase mRNA variant lacking exons I-III in the adult rat brain. This cortical type mRNA variant seemed to be widely distributed in the tissues.

Animals↗