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Biomedical subjects

J Kobayashi

Publications and source records attributed to J Kobayashi.

At least 109 records · Page 6Linked to original sources
PubMed2000

Outbreak of coccidioidomycosis in Washington state residents returning from Mexico.

In July 1996 the Washington State Department of Health (Seattle) was notified of a cluster of a flulike, rash-associated illness in a 126-member church group, many of whom were adolescents. The group had recently returned from Tecate, Mexico, where members had assisted with construction projects at an orphanage. After 1 member was diagnosed with coccidioidomycosis, we initiated a study to identify further cases. We identified 21 serologically confirmed cases of coccidioidomycosis (minimum attack rate, 17%). Twenty cases (95%) occurred in adolescents, and 13 patients (62%) had rash. Sixteen symptomatic patients saw 19 health care providers; 1 health care provider correctly diagnosed coccidioidomycosis. Coccidioides immitis was isolated from soil samples from Tecate by use of the intraperitoneal mouse inoculation method. Trip organizers were unaware of the potential for C. immitis infection. Travelers visiting regions where C. immitis is endemic should be made aware of the risk of acquiring coccidioidomycosis, and health care providers should be familiar with coccidioidomycosis and its diagnosis.

Adolescent↗
PubMed2000

Two-dimensional analysis of vocal fold vibration in unilaterally atrophied larynges.

OBJECTIVE: Considerable inconsistencies regarding the vibratory pattern of the vocal fold among patients with unilateral vocal fold paralysis (UVFP) have been reported. These differences are derived from differences in the position, stiffness, and atrophy of the paralyzed vocal fold and other factors among patients. The purpose of this study was to assess the effects of unilateral atrophy of the vocal fold on vocal fold vibration. METHODS: Seven excised canine larynges were studied. The unilateral recurrent laryngeal nerve was severed to cause vocal fold atrophy in four of the seven. The lateral and vertical displacements were monitored simultaneously with photoglottography and a laser Doppler vibrometer, respectively. Videostroboscopy of each larynx was also performed before and after the experiment to translate photoglottographic output into absolute lengths. Atrophy of the unilateral vocal fold was confirmed histologically. RESULTS: The lateral amplitude was significantly greater than the vertical amplitude in all larynges. The Lissajous trajectories in the normal larynges were shaped like a reverse crescent. Vibration in the unilaterally atrophied larynges was periodical and symmetrical in phase when the thyroid ala on the atrophied side was pressed medially. The lateral and vertical amplitudes on the atrophied side were significantly greater than those on the normal side. The Lissajous trajectories differed from those of the normal larynges. CONCLUSIONS: In the absence of a prephonatory glottal gap, periodical vibration occurs in unilaterally atrophied larynges and the amplitude of vibrations of the atrophied vocal fold is greater in the lateral and vertical directions than that of the normal fold. This implies that phonosurgical procedures aiming at closure of the prephonatory glottal gap may have a beneficial effect on hoarseness in UVFP patients, although displacements of the vocal folds during vibration are not symmetrical.

Animals↗
PubMed2000

Purification and characterization of an insect haemolymph protein promoting in vitro replication of the Bombyx mori nucleopolyhedrovirus.

We have identified a novel protein that promotes Bombyx mori nucleopolyhedrovirus (BmNPV) replication in vitro. This protein was purified from heat-treated haemolymph of B. mori larvae by gel filtration and ion exchange chromatography, and designated as promoting protein (PP). The molecular mass of native PP estimated by column chromatography and that of denatured PP estimated by SDS-PAGE were 9600 Da and 15200 Da, respectively, suggesting that native PP is composed of a single polypeptide and may behave in the column as if it is a smaller protein because of its conformation and/or adsorptive nature. Addition of the PP to the culture medium of SES-BoMo-15A cells derived from B. mori embryos resulted in the strong promotion of BmNPV replication. The promoting activity positively correlated with the amount of PP in the culture medium up to 1 microg/ml, above which maximum virus replication occurred and resulted in the highest budded virus production and polyhedrin promoter-mediated luciferase gene expression of 10000-fold and 6000-fold higher than those without PP, respectively. A cDNA encoding the PP precursor (prePP) was successfully cloned and sequenced. Comparison between the amino acid sequence deduced from the nucleotide sequence of prePP cDNA and the N-terminal 18 amino acids determined for the purified PP indicated that the prePP (154 amino acids) consisted of a mature PP polypeptide (136 amino acids) with a signal sequence at the N terminus. Recombinant PP expressed from the cDNA using a baculovirus vector was similar in molecular mass, immunoreactivity and promoting activity to the native PP.

Amino Acid Sequence↗
PubMed2000

Multidrug resistance reversal activity of taxoids from Taxus cuspidata in KB-C2 and 2780AD cells.

Some non-taxol-type taxoids having neither an oxetane ring at C-4 and C-5 nor an N-acylphenyl-isoserine group at C-13, such as taxuspine C, 2'-desacetoxyaustrospicatine, and 2-desacetoxytaxinine J, which were isolated from the Japanese yew Taxus cuspidata, increased cellular accu-mulation of vincristine (VCR) in multidrug-resistant 2780AD cells as potently as verapamil, and efficiently inhibited [(3)H]azidopine photolabeling of P-glycoprotein (P-gp). Taxuspine C, 2'-desacetoxyaustrospicatine, and 2-desacetoxytaxinine J at 10 microM completely reversed the resistance to colchicine, VCR, and taxol in KB-C2 cells, which overexpress P-gp, while taxinine and taxinine M showed no effect. Taxuspine C, 2'-desacetoxyaustrospicatine, and 2-desacetoxytaxinine J may be candidate pharmaceuticals for reversing multidrug resistance (MDR) and also may be good modifiers of MDR in cancer chemotherapy.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

A case of false median cleft of upper lip with IV-A holoprosencephaly that underwent cheiloplasty at 2.5 years of age.

Holoprosencephaly results from the incomplete development of midline structures within the cerebrum and encompasses a series of abnormalities of mid-facial development. Here, we report a case of male holoprosencephaly associated with false median cleft of upper lip. This patient belonged clinically to the DeMyer's group IV holoprosencephaly, semilobar type. An infant with this type of holoprosencephaly has been thought to die generally within 1 to 2 years after birth and to rarely benefit from an operation. In this case, the patient had cheiloplasty at the age of 2.5 years at the request of his parents and he lives currently, being 3 years and 2 months old.

Child, Preschool↗
PubMed2000

Preservation of collagen-induced whole blood platelet aggregation by tranexamic acid therapy in primary cardiac valve surgery.

Haemostatic disorder is one of the most common complications following cardiac surgery with cardiopulmonary bypass (CPB). Tranexamic acid reduces blood loss and allogeneic blood transfusion requirement in cardiac surgery. It had been thought that tranexamic acid inhibited fibrinolysis alone following CPB. In the present study, the haemostatic effects of tranexamic acid (20 mg/kg body weight bolus after induction of anaesthesia followed by continuous infusion at 2 mg/kg/h), including fibrinolysis and platelet function, were investigated in 22 patients (tranexamic acid group n = 12; control group n = 10) undergoing primary cardiac valve surgery. Fibrinolysis following CPB was reduced significantly in the tranexamic acid group. Following protamine administration, the reduction of collagen-induced whole blood platelet aggregation was mitigated significantly in the tranexamic acid group compared with the control group (36% reduction in the tranexamic acid group vs 58% in the control group; p = 0.011), although platelet counts did not differ between the two groups. In conclusion, tranexamic acid not only inhibits fibrinolysis directly, but also may preserve platelet function following CPB.

Adult↗
PubMed2000

Structure-activity relationships for the Ca2+-releasing activity of 6-hydroxy-beta-carboline analogues in skeletal muscle sarcoplasmic reticulum-the effects of halogen substitution at C-5 and C-7.

This study of structure-activity relationships of 6-hydroxy-beta-carboline analogues has been performed on the basis of quantitative measurement of Ca2+-releasing activity in the sarcoplasmic reticulum of skinned fibres of skeletal muscle. Substitution of halogens for hydrogens at the C-5 and C-7 positions and further introduction of a methyl group into the N-9 position of 6-hydroxy-beta-carboline resulted in Ca2+-releasing activity. The 50% effective concentrations of 5,7-dibromoeudistomin D, 5,7-dichloroeudistomin D, 5,7-diiodoeudistomin D, 9-methyl-5,7-dibromoeudistomin D, 9-methyl-5,7-dichloroeudistomin D, 9-methyl-5,7-diiodoeudistomin D, and caffeine were 5.6 x 10(-6), 6.3 x 10(-6), 7.8 x 10(-6), 2.1 x 10(-6), 2.0 x 10(-5), 3.7 x 10(-5), and 4.7 x 10(-4) M, respectively, indicating that these analogues are 10-200 times more potent than caffeine. Substitution of bromine by chlorine or iodine at the C-5 and C-7 positions markedly reduced the activity of the analogues with a methyl group at the N-9 position. These results suggest that halogens at the C-5 and C-7 positions in the beta-carboline skeleton are essential for Ca2+-releasing activity and that an N-9 methyl group also affects the activity of these analogues. Thus, these 6-hydroxy-beta-carboline analogues might become powerful tools for studying the molecular mechanism of Ca2+ release in the sarcoplasmic reticulum.

Animals↗
PubMed2000

The hypoglycemic effect of (7R*,9aS*)-7-phenyl-octahydroquinolizin-2-one in mice.

(-)-Multiflorine (1), which was isolated from leguminous plants, produced a hypoglycemic effect when administered to mice with streptozotocin-induced diabetes. (-)-Multiflorine has an enaminone type conjugation on the A-ring, which is unusual in lupine alkaloids. Proceeding on the assumption that the A-B ring is responsible for the activity, several compounds bearing quinolizidin-2-one were synthesized and their hypoglycemic effects were examined. The hypoglycemic effect of (7R*,9aS*)-7-phenyl-octahydroquinolizin-2-one was approximately 4 times stronger than that of (-)-multiflorine measured by oral glucose tolerance test in normal mice. This result indicates that compounds possessing the quinolizidin-2-one ring system as the basic structure may be possible lead compounds for a new type of diabetes drug.

Alkaloids↗
PubMed2000

Pyrinodemins B-D, potent cytotoxic bis-pyridine alkaloids from marine sponge amphimedon sp.

New bis-pyridine alkaloids, pyrinodemins B-D (1-3), have been isolated together with pyrinodemin A (4) and related 3-alkyl pyridine alkaloids 5-8 from the Okinawan marine sponge Amphimedon sp. and the structures were elucidated from spectroscopic data. Pyrinodemins B-D (1-3) showed potent cytotoxicity, while compounds 5-8 exhibited antimicrobial activity.

Alkaloids↗
PubMed2000

[Development of trace metal ion analysis].

Analyses of trace biologically essential or toxic ionic compounds found in the environment are very important. However, the lack of sensitivity and interference caused by coexisting components are often serious problems. To determine trace levels of metal ions without the above problems, new preconcentration and analytical methods have been developed. Firstly, three methods for the selective preconcentration of metal ions are shown below: 1) 3-Chloropyridazine-6-carbohydrazide was immobilized on glass beads supports to be used as a column packing material. Multi-metal ions were concentrated on the column and eluted selectively with several buffers and hydrochloric acid. The eluate was analyzed off-line by flame atomized-atomic absorption spectrometry (AAS). This method was able to determine sub-ppb levels of cupper- and cadmium-ions in environmental samples. 2) Salicylideneamino-2-thiophenol was immobilized on the supports. Aluminum ion was concentrated selectively on the column and eluted with nitric acid. The eluate was analyzed off-line by flameless-AAS or on-line by flow injection analysis using pyrocatechol violet for a post-column colorimetric reagent. These methods were able to determine ppb-ppt levels of aluminium in environmental samples and were suitable for its state-analysis. 3) Bathocuproinesulfonic acid was immobilized on the supports. Copper ion was concentrated selectively on the column and eluted with nitric acid. The eluate was analyzed on-line by flow injection analysis using bathocuproinesulfonic acid. This method was able to determine sub-ppb levels of copper in environmental samples. On the other hand, to analyze simultaneously trace metal ions and anions, capillary electrophoresis was performed using ethylenediaminetetraacetic acid as an electrolyte component. Simultaneous determination of several ions in mineral waters was achieved by the system.

Chelating Agents↗
PubMed2000

Cardiac transplantation under new legislation for organ transplantation in Japan: report of two cases.

During the past 2 years since new legislation for organ transplantation from brain-dead donors came into effect in Japan, 3 cardiac transplants have been carried out, 2 of which were performed at the National Cardiovascular Center (NCVC). The recipient cases were 46- and 25-year-old male patients who suffered from end-stage dilated cardiomyopathy and had been listed for cardiac transplantation in the Japan Organ Transplantation Network as status I candidates. The first patient was supported by the use of a paracorporeal air-driven left ventricular assist device of the NCVC type, and had a moderate degree of renal and hepatic dysfunction at the time of transplantation. Donor hearts were transported from distant hospitals (Tokyo and Miyagi prefecture) and the transportation time was 1 h 33 min and 2h 4 min, respectively. The operation was performed by the standard technique (Lower-Shumway) in the first patient and by the bicaval anastomosis technique in the second patient. Reperfusion of the transplanted heart was performed retrogradely through the coronary sinus utilizing leukocyte-depleted blood with a gradual increase in temperature. Total ischemic time was 3 h 34 min and 3 h 35 min, respectively. Weaning from the cardiopulmonary bypass was easy and uneventful in each patient. Immunosuppressive therapy was conducted with OKT-3 induction in the first patient because of the coexisting renal dysfunction and with a triple immunosuppressive regimen for both patients. Routine endomyocardial biopsy showed acute rejection of less than grade Ib, and the patients were discharged on the 65th and 46th postoperative day, respectively. At present, both patients are in the NYHA class I state and are ready to return to work. The uneventful recovery seen in these patients shows the advances made in transplant medicine, including the progress and improvement of immunosuppressive therapy, surgical techniques, myocardial protection, and detection and treatment of infection. Further efforts are required to fully establish the cardiac transplantation program in Japan.

Adult↗
PubMed2000

A clinical feature of hyperlipidemia in patients with central diabetes insipidus.

In this study, we analyzed plasma lipid and lipoprotein levels before and after treatment with 1-desamino-8-D-arginine vasopressin (DDAVP) in subjects with partial and complete central diabetes insipidus (DI) in order to determine how a shortage and supplement of this hormone affect plasma lipid metabolism. The subjects consisted of 6 patients with partial and 6 with complete central DI. After treatment with DDAVP through nasal cavity, plasma total cholesterol (TC) level did not decrease either in complete or partial form. Plasma triglyceride (TG) levels decreased from 306+/-175 mg/dl to 198+/-91 (35% decrease, p=0.027) in complete form, while TG did not change significantly in partial form. A detailed investigation of plasma lipoprotein metabolism during treatment with DDAVP was carried out in 3 of the 6 subjects with complete form of DI. Lipoprotein lipase activity and mass in post-heparin plasma from those three subjects tended to increase after treatment with DDAVP, along with the complete disappearance of an unusual lipoprotein between low density lipoprotein (LDL) and very low density lipoprotein (VLDL) as analyzed by polyacrylamide gel electrophoresis. These results suggest that the DDAVP treatment has a favorable effect on lipid and lipoprotein metabolism, especially triglyceride-rich lipoproteins, either directly or through modifying factors contributing to lipid metabolism.

Administration, Intranasal↗
PubMed2000

Long-term (14 years) effect of LDL apheresis on obstructive changes in aortocoronary saphenous-vein bypass grafts in a case of heterozygous familial hypercholesterolemia with the LDL receptor proline664 to leucine mutation.

A 61-year-old Japanese woman with heterozygous familial hypercholesterolemia (FH), type 2 diabetes mellitus and coronary artery disease underwent coronary artery bypass grafting (CABG) utilizing a saphenous vein graft at the age of 46, in June 1984, 6 months before low density lipoprotein (LDL) apheresis was started. She had received LDL apheresis every two weeks, along with combined drug treatment since the age of 47 (December 1984). She had bilateral xanthelasma and Achilles tendon xanthomas. Her fasting baseline serum total cholesterol and triglyceride level were 464 mg/dl and 57 mg/dl, respectively at the age of 47 when she visited our hospital for the first time. Analysis of the genomic DNA from the patient revealed heterozygous amino acid substitution of Leu for Pro664 in the LDL receptor gene. She was diagnosed as type 2 diabetes mellitus at the age of 53. Combined treatment in the steady state yielded a pretreatment LDL cholesterol level of 230+/-14 mg/dl and a posttreatment level of 57+/-7.6. All grafts were widely patent after as long as 14 years since CABG, suggesting that LDL apheresis combined with drug therapy is highly effective in preventing the occlusion of bypass grafts in a patient with heterozygous FH and type 2 diabetes mellitus.

Aorta↗
PubMed2000

[An experience with the Ross operation utilizing cryopreserved pulmonary homografts procured by and stored in our homograft valve bank].

Eight patients, 4 males and 4 females ranging in age from 10 to 54 years (mean 27 +/- 13 years) underwent the Ross operation using a cryopreserved pulmonary homograft harvested by and cryopreserved in our institutional "Tissue Bank". Seven patients had a congenital bicuspid aortic valve and 3 patients had had healed infective endocarditis of the aortic valve. Four young female patients wanted to have a baby after operation. The Ross procedure was carried out utilizing aortic root replacement techniques in all patients. All patients survived and are currently in NYHA class 1, but 2 cardiac events occurred in 2 patients during the mean follow-up term of 29 +/- 19 months. The one was the anastomic stenosis between the homograft and distal pulmonary artery treated by balloon dilatation and the other was ventricular tachycardia eventually managed by the insertion of an ICD. Pulmonary autograft valve regurgitation is present in 3 patients, but it is not progressive up to the present time. Pulmonary homograft valves function well in all patients. The Ross operation for adolescents and young adults should become more popular along with more easy availability of homograft valves based upon the establishment of the "Homograft Valve Bank" system in Japan.

Adolescent↗
PubMed2000

An epidemiological study on Opisthorchis viverrini infection in Lao villages.

The prevalence of liver fluke, Opisthorchis viverrini, infection in rural and urban communities was studied in Khammouane Province in Lao PDR. The infection was the commonest among the villagers examined, showing the positive rates of 52.9% and 55.0% in two rural communities and 60.7% in an urban community, respectively. The infection rate reached up to 20% or more within 4 years after birth and increased with age to a plateau in the age group over 20 years. The highest prevalence rate was over 80% in the age group of 35-54 years. The age-related patterns of infection in males and females were almost the same, although there were some sex-related differences by village and by age group. Infection with Opisthorchis viverrini appears to be a serious public health problem strongly associated with the frequent eating habit of raw fish in low land Laos.

Adolescent↗