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T Imada

Publications and source records attributed to T Imada.

At least 37 records · Page 2Linked to original sources
PubMed2000

Ileal duplication presenting as perforation: report of a case.

We describe herein the case of a 10-year-old boy in whom generalized peritonitis was caused by perforation of a tubular communicating ileal duplication cyst. Alimentary tract duplication cysts are rare congenital malformations, found primarily in children under the age of 15 years. The perforation was caused by heterotopic gastric mucosa within the duplication, giving rise to peptic ulceration in the adjacent intestinal mucosa. The presence of heterotopic gastric tissue is a primary cause of perforation that has been reported in as many as one third of patients with small intestine duplications; however, the detection of such ectopic tissue is time-consuming, and there is no readily available method of diagnosing tubular duplications. Although very few patients present with peritonitis as the initial manifestation, the possibility should be borne in mind when diagnosing and planning therapy for such emergencies, particularly in children.

Child↗
PubMed2000

Molecular modelling and conformational analysis of novel glycoprotein (Gp) IIb/IIIa antagonists. Molecular orbital calculation and the condensed heterocyclic derivatives.

A naphthalene compound was chosen as lead compound to develop a new series of fibrinogen receptor antagonists. Eight new compounds with different condensed heterocyclic parts were prepared and their in vitro activities were evaluated. 5-Amidinobenzofuran compound 2, 6-amidinobenzothiophene 7, and 5-amidinofuro[2,3-b]pyridine 8 were more active than lead compound 1. Molecular orbital calculation studies suggested the presence of a preferred spatial orientation between the amidine and the carboxylic acid.

Acetates↗
PubMed2000

Avian nephritis virus (ANV) as a new member of the family Astroviridae and construction of infectious ANV cDNA.

The complete RNA genome of the avian nephritis virus (ANV) associated with acute nephritis in chickens has been molecularly cloned and sequenced. Excluding the poly(A) tail, the genome comprises 6,927 nucleotides and contains three sequential open reading frames (ORFs). The first ORF (ORF 1a) contains a sequence encoding a serine protease motif, and the second ORF (ORF 1b) has a sequence encoding an RNA-dependent RNA polymerase. ORF 1a may be linked to the second ORF by a ribosomal frameshifting mechanism. The third ORF (ORF 2) may encode the virion structural proteins as a polyprotein precursor. Two RNAs, probably genonic and subgenonic RNA (7.5 and 3.0 kb), were detected in the cytoplasm of ANV-infected cells. ANV and human astroviruses have the same genonic organization, and both are characterized by the presence of two RNA bands. The amino acid homologies of the products of ORF 1a, 1b, and 2 were 20.3, 41.9, and 25.8% to products of the corresponding ORFs of human astrovirus serotype 1 (A/88 Newcastle strain). We have constructed a genonic-length cDNA clone of ANV to test whether the in vitro transcript is infectious. When a chicken kidney cell culture was transfected with RNA transcribed in vitro and the cDNA clone, infectious virus was produced with cytopathic effects in the absence of trypsin. These observations suggested that the ANV (G-4260 strain) is a new genus of the family Astroviridae.

Animals↗
PubMed2000

[The management of infectious mediastinitis after the open heart surgery].

Between October of 1992 and September of 1998, we performed 604 open heart operations. Among them, 12 cases (1.9%) were complicated with postoperative infectious mediastinitis. Five patients (Group A) were treated by conservative therapy which consists of open drainage and intermittent closed irrigation with dilute povidone iodine solution. Seven patients (Group B) were treated surgically in addition to the above-mentioned conservative treatment. Among those patients, one patient developed fatal complication. We have realized that mental care of the patients was also very important when long term hospitalization was necessitated. The hyperbaric oxygen therapy seemed to be also effective for postoperative mediastinitis caused by MRSA.

Aged↗
PubMed2000

[The management of aortic root replacement using the Top-Hat/Gelweave composite graft].

Composite graft replacement of the aortic root has become a routine procedure for annuloaortic ectasia (AAE) and aortic valve insufficiency (AR) with aortic dissection and the results have improved. We treated six cases of aortic root reconstruction using the Carrel patch method in 1998. The Top-Hat/Gelweave Composite graft fit together well and the procedure is technically similar to standard valve replacement. Upon measuring the valve size a Gelweave graft 1 mm larger than the valve size should be selected. There were no incidence of hemorrhage or postoperative hemolysis. Further long-term follow-up is necessary.

Aged↗
PubMed2000

[Retrograde continuous cold blood cardioplegia for combined aortic valve replacement and coronary artery bypass grafting].

Efficacy of retrograde continuous cold blood cardioplegia (RCBC) during aortic valve replacement combined with coronary bypass grafting was studied. Forty patients underwent elective aortic valve replacement, either combined with coronary bypass grafting (7 patients: group I), or isolated (33 patients: group II) using RCBC between 1996 and 1999 were analyzed retrospectively. Aortic cross clamp time was significantly prolonged in group I (150 +/- 33 min) compared to group II (109 +/- 32 min). The postoperative peak creatine kinase-MB levels were similar in both groups (73.3 +/- 23.9 versus 97.6 +/- 88.7 ng/ml). The doses of dopamine and dobutamine administered during 24 hours after surgery did not differ between the two groups (7.5 +/- 3.9 versus 6.5 +/- 5.5 mg/kg). The early (< 30-day) mortality was 0 in group I, and 3.0% in group II. These results suggest that RCBC is a safe method of myocardial protection in patients undergoing aortic valve replacement combined with coronary artery bypass grafting.

Aged↗
PubMed2000

[Combined 5-FU and CDDP in a gastric cancer patient undergoing hemodialysis--pharmacokinetics of 5-FU and CDDP].

The pharmacokinetics of 5-FU and CDDP was examined in a gastric cancer patient receiving regular hemodialysis (HD) for renal failure. The patient received combination chemotherapy of 5-FU and CDDP, then on the day of HD we measured the plasma concentration of 5-FU, total platinum, and non-protein-bound platinum of the patient. In the present case, the 5-FU concentration was kept at an almost even level during HD. Non-protein-bound platinum disappeared after being maintained in blood for a certain time when HD was started 30 minutes after the end of CDDP administration. From these findings, we conclude that combined 5-FU and low-dose CDDP therapy should be done by decreasing the dose of 5-FU, administrating CDDP only on the day the patient undergoes HD, and starting HD 30 minutes after the end of CDDP administration.

Adult↗
PubMed1999

Association between high serum alanine aminotransferase levels and more rapid development and higher rate of incidence of hepatocellular carcinoma in patients with hepatitis C virus-associated cirrhosis.

BACKGROUND: Many studies have demonstrated in animal experiments that persistent inflammation may accelerate the development of carcinoma. In this article, the question of whether the persistent elevation of serum alanine aminotransferase (ALT) levels (which represents the inflammatory necrosis of hepatocytes) correlates with the development of hepatocellular carcinoma (HCC) was studied in patients with early stage hepatitis C virus (HCV)-associated cirrhosis. METHODS: Sixty-nine consecutive patients with biopsy proven HCV-associated cirrhosis (mostly Child's Stage A) who had been followed for >5 years for the development of HCC were studied. They were subdivided into 3 groups according to their serum ALT levels: Group A was comprised of 28 patients whose annual average serum ALT level was persistently high (>/= 80 IU) (high ALT group), Group B was comprised of 28 patients whose annual average serum ALT level was persistently low (< 80 IU) (low ALT group), and Group C was comprised of 13 unclassified patients. The patients had been studied prospectively with frequent ultrasonography and magnetic resonance imaging or computed tomography for > 5 years. RESULTS: In the high ALT group HCC developed in 71.4% of patients compared with 25.0% in the low ALT group over the observation period (P < 0.005). The 5-year rate of incidence of HCC in the high ALT group was as high as 53.6% compared with only 7.1% in the low ALT group (P < 0.001). The expected interval between the diagnosis of cirrhosis and the development of HCC was 6.0 +/- 0.7 years (mean +/- standard error) in the high ALT group and 12.7 +/- 1.2 years in the low ALT group (P < 0.001). CONCLUSIONS: The results of the current study demonstrated that the development of HCC was more rapid in the high ALT group with HCV-associated cirrhosis.

Aged↗
PubMed1999

Dynamic cortical activation in mental image processing revealed by biomagnetic measurement.

The mental rotation task has been reported to activate the human parietal and extra-striate areas, based on the results of fMRI and PET analysis. In the present study, we investigated the dynamic properties of the distributed cortical activity related to mental rotation processes at high temporal resolution by means of brain magnetic field measurements and a linear inversion algorithm. Distributed neural activities during the mental rotation and control tasks were estimated for six subjects, and the differences in the activity distribution were analyzed. Statistically significant differences in the parietal and lateral posterior temporal region were detected 200-300 ms after the visual stimulus, indicating that the dorsal and ventral pathway were included in the mental image processing.

Adult↗
PubMed1999

Ipsilateral movement-evoked fields reconsidered.

The generation mechanism of movement-evoked fields (MEFs) is poorly known and the existence of ipsilateral MEFs is still in dispute. We recorded whole-scalp neuromagnetic activity from eight subjects who were pressing response keys alternately with the right 2nd and 4th digits, while keeping the left palm on the table containing the keys. Clear ipsilateral MEFs peaked 58 +/- 2 ms after the key touch, with sources in the hand area of the right primary somatosensory cortex. The ipsilateral MEFs decreased to half size when the resting left hand was palm up on the table. However, very similar responses were obtained when another person operated the response keys and the subjects just kept their left palm on the table. No signals were elicited when the subjects only viewed these actions with no hand contact to the table. The results indicate that the MEFs receive a strong contribution from tactile input. In our experiment the ipsilateral sensorimotor activation was triggered by the movement-related vibrations transmitted to the resting hand.

Adult↗
PubMed1999

Apoptosis and proliferative activity in thyroid tumors.

To clarify the growth mechanisms of thyroid tumors, we examined apoptotic cells in 61 thyroid tumors, consisting of 14 adenomas, 35 papillary carcinomas, 4 follicular carcinomas, and 8 undifferentiated carcinomas, using terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate digoxigenin-nick end labeling (TUNEL). The proliferative activity was also evaluated immunohistochemically using the monoclonal antibody to Ki-67 antigen (MIB-1) in the same tumors. The apoptotic index (AI) was expressed as a percentage of the TUNEL-positive cells in the tumor cells, and a proliferation index (PI), being the percentage of Ki-67 positive cells, was calculated for each tumor. The overall level of AI was very low in all histotypes of the thyroid tumors analyzed, the mean AI being 0.5 +/- 0.4 in adenoma, 0.4 +/- 0.3 in differentiated carcinoma, and 1.8 +/- 1.5 in undifferentiated carcinoma. The PI in the thyroid tumor subtypes was significantly lower in adenoma and differentiated carcinoma, at 0.5 +/- 0.7 and 1.1 +/- 0.7, respectively, than that in undifferentiated carcinoma at 14.5 +/- 3.7 (P < 0.05). There was no correlation between clinicopathological factors and AI or PI in differentiated thyroid carcinoma. Our findings suggest that apoptosis occurs infrequently in thyroid tumors, and that proliferative activity markedly differs according to the thyroid tumor subtypes. Moreover, the ratio between proliferating cells and apoptotic cells may reflect thyroid tumor progression.

Adenocarcinoma, Follicular↗
PubMed1999

Intrathoracic omental herniation through the esophageal hiatus: report of a case.

We report herein an extremely rare case of intrathoracic omental herniation through the esophageal hiatus. In fact, according to our review of the literature, only eight other cases have been reported, most of which were misdiagnosed as mediastinal lipoma after being identified as an intrathoracic mass. We report herein the ninth case of intrathoracic omental herniation through the esophageal hiatus. A 54-year-old obese woman was admitted to our hospital for investigation of a chest roentgenographic abnormality. She was asymptomatic, and her physical examination and laboratory data were all within normal limits. Her chest X-ray demonstrated a large, sharply-defined mass, and a computed tomography scan of the thorax indicated a large mediastinal mass with fat density. A thoracotomy was performed under the diagnosis of a mediastinal lipoma which revealed an encapsulated fatty mass, 10x7.5x6 cm in size, that proved to be an omental herniation through the esophageal hiatus. There was no herniation of the stomach or intestines into the thorax. The esophageal hiatus was repaired after the omental mass and hernia sac had been resected. This case report serves to demonstrate that whenever a mass of fat density is recognized in the lower thorax, an omental herniation should be borne in mind as a possible differential diagnosis.

Diagnosis, Differential↗
PubMed1999

Are there discrete distal-proximal representations of the index finger and palm in the human somatosensory cortex? A neuromagnetic study.

OBJECTIVE: The distal-proximal representations of the finger and palm in the first somatosensory cortex (SI) were studied in humans. METHODS: Somatosensory evoked magnetic fields (SEFs) from 11 subjects were measured, following mechanical stimulation of the skin by using a 122 channel whole head SQUID system. Sensory stimulus comprising of a 10 ms vibration at the frequency of 200 Hz was delivered to 6 successive sites in 3 cm increments, along the distal-proximal direction over the volar surface of the right index finger and palm. Using a single dipole model, the sources of the magnetic fields were estimated and mapped onto magnetic resonance images of each subject. ANOVA was used for statistics. RESULTS: Source localization was determined on the main peak (M50) of the SEFs. All of the sources were located in the area 3b of SI. Contrary to the well-defined distal-proximal representations in the hand area of simian SI cortex, there was no statistically significant differences between the locations of the dipoles in human SI cortex evoked by stimulation of different sites. CONCLUSION: The result, however, should be interpreted with caution, because it cannot be denied that the spatial separation of sources in the distal-proximal somatotopy is beyond the resolving capacity of magnetoencephalography (MEG). In addition, at variance with the discrete distal-proximal gradient in the mechanoreceptor density, there was no statistically significant differences between the signal strengths of the dipoles for stimulation of the different locations.

Adult↗
PubMed1999

Effect of trypsin inhibitor on reflux oesophagitis after total gastrectomy in rats.

OBJECTIVE: To characterise alkaline reflux oesophagitis after total gastrectomy in rats from the standpoints of cell proliferation and apoptosis and from its macroscopic and microscopic findings, and to evaluate the preventive and curative effects of camostat mesilate, a trypsin inhibitor. DESIGN: Open laboratory study. SETTING: University hospital, Japan. ANIMALS: 70 male Wistar rats. INTERVENTIONS: Total gastrectomy with Billroth II anastomosis (n = 30) and with Roux-en-Y anastomosis (n = 30) were used to establish reflux oesophagitis. Camostat mesilate was given for prevention and cure. The remaining 10 animals had a sham operation. MAIN OUTCOME MEASURES: Trypsin activity of the oesophagus, macroscopic and microscopic findings, bromodeoxyuridine (BrdU) and apoptotic cell labelling indices. RESULTS: Reflux oesophagitis was more common and extensive after Billroth II than Roux-en Y anastomosis. The BrdU labelling index was increased in oesophagitis, while the apoptotic index did not change. Camostat mesilate was effective in both preventing and treating oesophagitis. CONCLUSION: Trypsin has an important role in the development of reflux oesophagitis after total gastrectomy.

Animals↗
PubMed1999

Preparation and pharmacological evaluation of novel glycoprotein (Gp) IIb/IIIa antagonists. 1. The selection of naphthalene derivatives.

The synthesis and design using molecular modeling techniques for non-peptide, low molecular weight novel fibrinogen receptor (glycoprotein IIb/IIIa: Gp IIb/IIIa) antagonists, is reported. We used a highly potent serine protease inhibitor, Nafamostat, having an amidinonaphthyl unit as the starting compound. The compounds 4-(6-amidino-2-naphthylaminocarbonyl)phenoxyacetic acid (5a) and 4-(6-amidino-2-naphthalenecarboxamido)phenoxyacetic acid (5b) inhibited adenosin-5'-diphospate (ADP)-induced aggregation of human platelet-rich plasma (PRP) with IC50 values of 0.05 and 0.07 microM, respectively, and had lost their ability to inhibit a variety of serine proteases, including thrombin, factor Xa, plasmin and trypsin.

Adenosine Diphosphate↗
PubMed1999

Preparation and pharmacological evaluation of novel glycoprotein (Gp) IIb/IIIa antagonists. 2. Condensed heterocyclic derivatives.

A novel series of platelet receptor glycoprotein (Gp) IIb/IIIa antagonists with condensed heterocycles as their basic core was synthesized. In an in vitro assay, trans-4-(5-amidinobenzofuran-2-carboxamido)cyclohexyloxyacetic+ ++ acid 17e and trans-3-[4-(5-amidinobenzofuran-2- carboxamido)cyclohexyl]propionic acid 17f produced marked inhibitions with IC50 values of 0.018 and 0.006 microM, respectively in a human platelet adenosin-5'-diphospate (ADP)-induced aggregation assay; they also exhibited a wide spectrum of inhibition toward major aggregation agonists (ADP, collagen, thrombin, PMA (tumor promoter) and arachidonic acid). These compounds were > 2-3 orders of magnitude more effective in inhibiting platelet aggregation than human umbilical vein endothelial cell (HUVEC) binding. The oral administration of 10 mg/kg of either 17e and 17f to guinea pig, resulted in a 60% inhibition of ex vivo platelet aggregation after 5 h. Oral administration of ethyl trans-4-(5-amidinoben-zofuran-2- carboxamido)cyclohexyloxyacetate 18e (10 mg/kg) resulted in 80% inhibition of platelet aggregation in dogs for 6 h after oral administration with a return to baseline by 24 h. Ethyl trans-3-[4-(5-amidinobenzofuran-2-carboxamido)cyclohexyl]propionat e 18f (AR0598) produced 80% inhibition for 5 h after oral administration. Prodrug 18e showed a good profile in dogs with a long duration of action. 18e (AR0510) was selected as suitable clinical candidate for development as an orally active antithrombotic agent.

Adenosine Diphosphate↗
PubMed1999

Susceptibility of bovine naked 2- and 4-cell embryos and hatched blastocysts produced in vitro to infection with noncytopathogenic bovine viral diarrhea virus.

To investigate the susceptibility of early bovine embryos to noncytopathogenic bovine viral diarrhea virus (NCP BVDV), 2- and 4-cell embryos produced in vitro from which zona pellucida had been removed by pronase treatment, and hatched blastocysts were exposed to 10(6) TCID50/m/ of NCP BVDV No. 12 strain. The virus was detected in all embryo samples immediately prior to cultivation but not in the medium. After 24-hr culture, the virus was isolated from four media and two embryo samples in four experiments in the blastocyst group, and the viral antigen was demonstrated in the cytoplasm of the embryo cells by the immunofluorescent technique. By contrast, no virus was recovered from, or viral antigen detected in samples from the 2- and 4-cell embryo group in any of the experiments, even though they were exposed to the virus after removal of the zona pellucida. These findings suggest that 2- and 4-cell embryos are unlikely to be susceptible to NCP BVDV, but that blastocysts are capable of being infected with the virus. hatched blastocyst, noncytopathogenic bovine viral diarrhea virus.

Animals↗