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Biomedical subjects

K Shibata

Publications and source records attributed to K Shibata.

At least 415 records · Page 23Linked to original sources

Developmental differences of angiotensinogen mRNA in the preoptic area between spontaneously hypertensive and age-matched Wistar-Kyoto rats.

In order to know the possible involvement of the central angiotensin system in hypertension, angiotensinogen mRNA (AomRNA) levels of eight discrete brain areas were measured by Northern blot hybridization analysis in the spontaneously hypertensive rats (SHR), compared with those in age-matched normotensive Wistar-Kyoto rats (WKY). In 16-week-old SHR (hypertensive stage), AomRNA levels in the preoptic area (POA), but not in the ventromedial hypothalamus, lateral hypothalamus and mammillary body, among the hypothalamic nuclei, were higher (approximate 50%) than in WKY. There were no differences in other brain areas, such as the striatum, septum, amygdala and cerebellum between both the strains. The AomRNA levels in POA were already higher (38%) in 4-week-old SHR (prehypertensive stage) without significance, and the difference was augmented (82%) in 7-week-old SHR (evolving stage). These results suggest that the developmental changes of AomRNA levels at POA may be related in some aspect to hypertension process.

Aging↗

An attempt to substitute the cell binding domain of human fibronectin in lambda phage J protein: computer design and expression.

We superimposed hydropathic indexes of the human fibronectin cell binding domain (CBD) on the lambda phage J protein by computer, and substituted 22 amino acids from the fibronectin CBD for a part of the lambda phage J protein. The fibronectin cell binding domain -Arg-Gly-Asp-Ser- (-RGDS-) localizes at the junction of hydrophobicity and hydrophilicity. We selected a similar hydrophobic-to-hydrophilic junction in the J protein region for substitution. This junction corresponds to 150 bp of the PstI fragment of J protein cDNA. We synthesized 150 bp of the relevant PstI fragment that includes the cell binding domain region. The region was then constructed by serial cloning as an expression vector, pJCBD. The vector pJCBD expressed the fused protein named JCBD (M(r) 32 kDa) in E coli XL1-BLUE. The expressed JCBD protein was identified by Western blot analysis in the extract of the pJCBD carrying bacterial lysate using both rabbit anti-lambda phage antiserum and anti-CBD of fibronectin antibody. The JCBD protein appeared to recognize retinoblast cell membrane RGDS-directed receptors, detected by enzyme-linked immuno-sorbent assay and also by binding competition assay with synthetic pentapeptides, Gly-Arg-Gly-Asp-Ser (GRGDS) and Gly-Arg-Gly-Glu-Ser (GRGES). The former competitor inhibited completely fibronectin CBD-dependent binding activity of JCBD, the latter had no inhibitory activity. These results suggest that certain functional proteins engineered by computer design between human fibronectin cell binding domain and lambda phage J protein can be produced.

Amino Acid Sequence↗

Role of intramolecular high-mannose chains in the folding and assembly of soybean (Glycine max) lectin polypeptides: studies by the combined use of spectroscopy and gel-filtration size analysis.

It was previously reported [Nagai, K. & Yamaguchi, H. (1993) J. Biochem. 113, 123-125] that intramolecular high-mannose chains are essential for reconstitution of soybean lectin from denatured subunits. To obtain more detailed information on the role of the intramolecular high-mannose chains in the folding and assembly of soybean lectin polypeptides, the effects of asparagine-linked oligosaccharides, Man9GlcNAc2Asn (M9-Asn) and Glc1-3Man9GlcNAc2Asn (GM9-Asn), on the reconstitution of soybean lectin from denatured subunits were examined by comparison with the denaturation features of the lectin with varying concentrations of guanidine hydrochloride. The combined use of spectroscopy and size-analysis by gel filtration revealed that both the folding and assembly of denatured subunit polypeptides were completely prevented in the presence of 300 microM M9-Asn, whereas the same concentration of GM9-Asn only interfered with the polypeptide assembly, exhibiting no significant effect on the polypeptide folding. These results, considered together with those in the previous report, indicate that the sugar branch Man alpha 1-2Man-alpha 1-2Man linked to the 3 position of the beta-mannosyl residue of the high-mannose chains functions in the folding of the subunit polypeptides, and that other branches participate in the subunit assembly.

Asparagine↗

Plasma-depleted platelet concentrates prepared with a new washing solution.

In certain clinical situations, complete removal of the plasma proteins from the platelet concentrates (PCs) is necessary by washing prior to transfusion. A simple electrolyte solution with a pH of 6.5 was developed for washing PCs. The platelet-rich plasma collected with acid-citrate-dextrose solution by apheresis in a 0.6-liter polyolefin bag was centrifuged. After removal of the supernatant plasma from pelleted platelet buttons, 200 ml of a washing solution consisting of 90 mM NaCl, 5 mM KCl, 3 mM MgCl2, 17 mM NaH2PO4, 8 mM Na2HPO4, 23 mM Na acetate, 17 mM Na3 citrate, 23.5 mM glucose, 2 mM adenine, 0.1% dextran, and 28.8 mM maltose (pH 6.5) was added to the pelleted platelet button. Steam sterilization of the solution was carried out under nitrogen to avoid caramelization of glucose. After resuspension of the pelleted platelet button with a washing solution and a second centrifugation, Seto additive solution (Seto sol, pH 7.4) was introduced into the bag to resuspend the platelet buttons for storage for 3 days at 22 degrees C. All of these procedures were completed within 3 h using a sterile docking device. In washed PCs, 99.1% of the plasma was removed and platelet recovery was 96%. The washed PCs were compared for 3 days with plasma-poor PCs consisting of 11% plasma and 89% Seto solution. There were no significant differences in percent hypotonic shock response, aggregation, energy metabolism, and morphology of platelets between the two groups during 3 days, except for significant swelling of 3-day-old platelets in washed PCs.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Platelets↗

Antiandrogen. II. Oxygenated 2-oxapregnane steroids.

Oxygenated derivatives of 2-oxachlormadinone acetate (17-acetoxy-6-chloro-2-oxapregna-4,6-diene-3,20-dione) at C11, C15, and C16 were prepared as potential antiandrogenic agents. Biological evaluation showed the 15 beta-hydroxyl compound to have a high potent antiandrogenic activity when tested in the castrated male rat.

Androgen Antagonists↗

UK-1, a novel cytotoxic metabolite from Streptomyces sp. 517-02. I. Taxonomy, fermentation, isolation, physico-chemical and biological properties.

A new benzoxazole, UK-1, was isolated from the mycelial cake of an actinomycete strain 517-02. Based on morphological, cultural and physiological characteristics, strain 517-02 was seemed to be a close relative of Streptomyces morookaense. UK-1 showed potent cytotoxic activity against B16, HeLa and P388 cells and did not show any antimicrobial activity.

Animals↗

[Two cases with acquired immunodeficiency syndrome in our hospital].

We report two cases of AIDS whom we have recently experienced. One patient was a 54-year-old man who admitted our hospital due to third degree burn. In this case, we did not know whether or not he was suffered from AIDS, when he was delivered by the ambulance. In autopsy, pneumocystis carinii pneumonia and renal tuberculosis were found in addition to marked decrease of T cells in lymph nodes. The other patient was a 40-year-old man with remarkable symptoms of central nervous system. Route of infection of HIV is unknown. He had dementia, left hemiplegia, bulbar palsy, progressed to rigid decorticate posture and died of respiratory arrest due to involvement of the brain stem, despite of treatment including use of 3'-azido-2',3'-dideoxythymidine (AZT). Magnetic resonance (MR) images showed progressive cerebral atrophy and a diffuse high signal intensity area of cerebral white matter on T2-weighted MR images, suggesting the diagnosis of HIV-induced encephalopathy.

Acquired Immunodeficiency Syndrome↗

Optimal shape of prosthesis for tricuspid valve replacement.

To develop an optimal prosthesis for use in the tricuspid valve, we determined the change in cardiac performance associated with the change in shape of the anulus of the tricuspid valve using a metal ring of variable flat ratio (defined as the long/short axis). In experiment I in an isolated autoperfusion model with six dogs, the left ventricular stroke work under a constant left atrial pressure of 7 mm Hg were, in grams per beat per minute, 11.88 +/- 0.52 with a flat ratio of 1.0, 11.88 +/- 0.70 with a flat ratio of 1.3, 16.23 +/- 0.61 with a flat ratio of 1.6, and 11.22 +/- 0.38 with a flat ratio of 2.3 (mean +/- standard error of the mean). The volume was significantly higher with a flat ratio of 1.6 than with the other ratios (p < 0.05). In experiment II with six dogs in vivo, the blood flow of the pulmonary trunk artery was 0.57 +/- 0.03 L/min with a flat ratio of 1.0, 0.66 +/- 0.03 L/min with a flat ratio of 1.6, and 0.58 +/- 0.03 L/min with a flat ratio of 2.3; the flow was significantly larger with a ratio of 1.6 than with the other ratios (p < 0.05). Right ventriculography was performed in five dogs. The percentage of radial shortening of the apex close to the acute margin was 19.4% +/- 3.1% with a flat ratio of 1.0 and 49.2% +/- 5.1% with a flat ratio of 1.6 (p < 0.05). In conclusion, the best hemodynamic results were obtained with a flat ratio of 1.6, which showed more advantageous hemodynamics than do the ratios of conventional circular prostheses.

Animals↗

[A case of advanced gastric cancer responding well by preoperative chemotherapy with CDDP and MMC].

A 35-year-old female who suffered advanced gastric cancer (classified Borrmann type 3) with para-aortic lymph nodes swelling received chemotherapy preoperatively. These lymph nodes, which could be detected by abdominal CT scan, were highly suspected of metastasis from gastric cancer. The regimens of neoadjuvant chemotherapy were Mitomycin C (MMC) 8 mg/m2 and Cis-platinum (CDDP) 75 mg/m2, administered intravenously as one course. After she was given these two courses, we performed total gastrectomy, pancreatico-splenectomy, and lymph-adenectomy curatively. The patient has been maintained in an outpatient clinic for one and half years without any evidence of recurrence.

Adult↗

[A case of hypersensitivity pneumonitis induced by toluene diisocyanate presenting with transient bronchoconstriction].

A 50-year-old male spray paint worker was admitted with non-productive cough and dyspnea on exertion. Chest X-ray and chest CT showed diffuse interstitial shadows in the bilateral lung fields. After admission, the symptoms and chest X-ray findings improved over several days, and he was followed as an outpatient. He then developed nocturnal dyspnea with wheezing and dry cough every day. About two months later, chest X-ray showed more severe diffuse interstitial shadows which did not disappear after admission. Bronchoalveolar lavage and transbronchial lung biopsy revealed allergic exudative interstitial pneumonia, and he was treated with steroid therapy. Paint contains toluene diisocyanate, and challenge test to toluene diisocyanate was positive. In the early course, this case presented with bronchoconstriction; bronchial reversibility and bronchial hyperresponsiveness to methacholine were positive. Bronchoconstriction may cause worsening of respiratory symptoms in patients with hypersensitivity pneumonitis induced by isocyanates.

Alveolitis, Extrinsic Allergic↗

[An adult case of chickenpox with multiple nodular shadows on chest roentgenogram].

An adult case of chickenpox with a chest roentgenogram revealing multiple nodular shadows of 5 to 20 mm in diameter is reported. These shadows were different from those in previously reported varicella pneumonia cases especially with respect to size. Pulmonary function test showed disturbance in diffusion capacity, and bronchoalveolar lavage fluid analysis revealed a decreased CD4/CD8 ratio. Transbronchial lung biopsy showed mild alveolitis and focal exudation and hemorrhage into the alveolar space, which were thought to correspond to the relatively large nodules on the chest roentgenogram. These findings suggest that multiple nodular shadows on the chest roentgenogram may been seen in some patients with chickenpox.

Adult↗

[Peritoneal dialysis following open heart surgery in children].

From 1982 to 1991, 13 (3.9%) of 336 children who underwent open heart surgery required peritoneal dialysis postoperatively, including 5 with transposition of the great arteries, 4 with tetralogy of Fallot, 2 with ventricular septal defect, 1 each with atrioventricular canal defects and total anomalous pulmonary venous connection. Patients ages ranged from 12 days to 4 years (mean, 1 year and 4 months). The infusion catheter was directed toward diaphragm from the right lower quadrant, and the drainage catheter was placed in the pelvis from the left upper quadrant. Dialysis solution was instilled and drained simultaneously. Seven children (54%) recovered renal function, with six (46%) longterm survivors. Differences between patients who did and did not recovered renal function (Group A and Group B respectively) were examined. No significant intergroup difference existed in age or weight. PD was initiated significantly sooner in Group B (1.2 +/- 0.8 days) than in Group A (3.2 +/- 1.9 days) (p < 0.05). The negative fluid balance was 88.0 +/- 31 mL/kg/day in Group A and 78.4 +/- 25.0 mL/kd/day (NS). BUN and serum creatinine concentrations were slightly elevated in both group, but were not significant different. Patients in Group A were dialyzed from 3 days to 21 days (mean 9.9 +/- 6.4 days), and patients in Group B were dialyzed from 1 day to 14 days (mean 5.3 +/- 5.2 days) (NS). The central venous pressure (CVP) in Group A decreased while blood pressure (BP) and renal perfusion pressure (RPP) increased following initiation of PD. CVP increased in Group B, while BP and RPP decreased. All patients died of low cardiac output syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗

[Etiology of cholelithiasis].

The incidence of gallstone has been gradually increased in the last few decades in Japan and the recent study revealed that approximately 15% of the autopsy cases had biliary stones. In the last 25 year interval, the nature of gallstones was greatly changed. In detail, the incidences of cholesterol gallstone and black stone were increased from 46.7% to 66.9% and from 0.8% to 12.1%, respectively, whereas that of calcium bilirubinate stone was decreased from 41.5% to 21.0% of the whole cholelithiasis cases. The factors influencing these changes were probably due to recent increase of fat diet intake and decrease of ascariasis by improvement of environmental hygiene. However, the factors that caused the change in black stone has not been defined.

Adolescent↗

[Effect of Na-L-glutamate on mitochondrial function of ATP synthesis after prolonged preservation in rat heart].

We studied the effect of Na-L-glutamate (Glu) on mitochondrial functions of ATP synthesis after prolonged hypothermic preservation of rat hearts. We divided isolated rat hearts into the following three groups: group A, hearts without immersion as control; group B, hearts immersed in Euro-Collins solution (E-C) without Glu for 24 h at 4 degrees C; group C, hearts immersed in E-C with 10mM Glu for 24 h at 4 degrees C. Number of each group used was 6. Mitochondrial functions of ATP production were determined by measuring respiratory control index (RCI). P/O ratio and state III respiration rate. The ability of ATP production (oxidative phosphorylation rate, OPR) was calculated. RCI and P/O ratio of groups B and C were significantly lower than those of group A. RCI and P/O ratio of group C were significantly higher than that of group B. S3 rates of groups B and C were significantly lower than those of group A. S4 rate of group B was significantly higher than those of groups A and C. OPRs of groups B and C were significantly lower than that of group A. OPR of group C was significantly higher than that of group B. We concluded that Na-L-glutamate effectively protected mitochondrial functions to synthesize ATP during prolonged hypothermic preservation.

Adenosine Triphosphate↗

[Two resected cases of malignant fibrous histiocytoma originated from the thoracic soft tissues].

Two resected cases, a 56-year-old man and a 49-year-old man, of malignant fibrous histiocytoma originated from the soft tissues of chest wall were reported. In both cases, MFH was histologically diagnosed prior to our radical operation. One patient received an incisional biopsy and the other was a recurrent case after excisional resection in other hospital. We resected the whole chest wall together with the tumor sufficiently apart from the tumor margin. In one patient the defect of chest wall was reconstructed with the material made of bone cement which sandwiched between 2 sheets of marlex heavy mesh and covered by latissimus dorsi muscle flap on it. The other was reconstructed with single sheet of marlex heavy mesh and covered by rectus abdominis muscle flap. Recurrence was not seen in either of two patients, in spite of the general acknowledgment that MFH recurs frequently and locally. We considered that the extended wide resection including the whole chest wall should be performed, and that marlex heavy mesh and the pedunculated musculo-cutaneous flap was useful for the reconstruction of chest wall defect.

Histiocytoma, Benign Fibrous↗

[Imaged thoracoscopic surgery for bronchogenic cyst in posterior mediastinum--a case report].

A 44-year-old female with bronchogenic cyst in the posterior mediastinum was treated successfully by employing imaged thoracoscopic surgical methods in the same way as laparoscopic cholecystectomy. The patient was placed in the left lateral decubitus position. A first 3.5 cm skin incision was made in the seventh intercostal space on the mid-axillary line. A 10 mm, 0-degree Olympus wide angle telescope was inserted for observation into the thoracic cavity. And three more small skin incisions were done. A grasping forceps, a padron retractor and an electrode with J-hook tip were introduced through each incision. The cyst was completely dissected almost with the J-hook electrode. She was discharged on the 10th-postoperative day without complication and with minimal pain. We suggest that an indication of the imaged endoscopic surgery could be established for some benign mediastinal tumors.

Adult↗