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Biomedical subjects

K Nishimura

Publications and source records attributed to K Nishimura.

At least 199 records · Page 11Linked to original sources

Isolation and characterization of a light-sensitive mutant of Escherichia coli K-12 with a mutation in a gene that is required for the biosynthesis of ubiquinone.

Cells with a novel mutation that is lethal when the cells are exposed to visible light were isolated from Escherichia coli K-12. The mutation was mapped at 63 min on the linkage map of the E. coli chromosome, and the gene, designated visB, was cloned and sequenced. From its map position and the evidence that the gene product VisB exhibits homology with flavin monooxygenase of Pseudomonas fluorescens, the visB gene was deduced to be identical to the ubiH gene, which is a gene required for the biosynthesis of ubiquinone and is thought to be similar to the gene for flavin monooxygenase. The photosensitive phenotype appears to be due to the accumulation of the substrate for the reaction catalyzed by the visB (ubiH) gene product because other mutations that block earlier steps in the biosynthesis of ubiquinone can reverse the photosensitivity. The accumulated intermediates may produce active species of oxygen in the mutant bacteria upon illumination by visible light, and these active oxygen species may cause the death of the cells by a mechanism similar to that associated with mutations in visA (hemH).

Amino Acid Sequence

Usual interstitial pneumonia: histologic correlation with high-resolution CT.

The authors reviewed 46 cases of idiopathic pulmonary fibrosis with usual interstitial pneumonia (UIP), correlating findings on high-resolution computed tomographic (HRCT) scans with findings in specimens obtained at open lung biopsy and autopsy. The following HRCT findings were observed: (a) an accumulation of small cystic spaces with thick walls, (b) air bronchiolograms within areas of intense lung attenuation, (c) rugged pleural surfaces, (d) irregularly thickened pulmonary vessels, (e) bronchial wall thickening, and (f) slightly increased lung attenuation. Macroscopic honeycombing correlating with small cystic spaces was demonstrated at HRCT and pathologic examination. Air bronchiolograms in the areas of intense lung attenuation (ie, microscopic honeycombing) corresponded to dilated bronchioles (greater than 1 mm in diameter) with fibrosis. Irregularly thickened vessels and bronchial walls and irregular pleural surfaces were the result of fibrosis in the periphery of the secondary pulmonary lobules. Areas of slightly increased lung attenuation seen on the HRCT scans correlated with patchy alveolar septal fibrosis or inflammation. The authors conclude that microscopic honeycombing and a perilobular distribution in UIP may be clearly identified with HRCT.

Adult

Diffuse panbronchiolitis: correlation of high-resolution CT and pathologic findings.

Diffuse panbronchiolitis (DPB) is characterized by chronic airflow limitation and airway inflammation with bronchiolar lesions. Chest radiographs of patients with DPB usually show small nodular shadows throughout both lungs. The authors investigated the nature and pathogenesis of the radiologic features of DPB by correlating high-resolution computed tomographic (HRCT) findings with histopathologic features. The HRCT images of nine patients with DPB were compared with the observations made with inflated lung specimens. The HRCT findings of DPB included centrilobularly distributed, small rounded areas of attenuation; branched linear areas of attenuation, contiguous with the small rounded areas; dilated airways with thick walls, also common outside secondary pulmonary lobules; and decreased lung attenuation in peripheral areas due to air trapping caused by bronchiolar narrowing in the subpleural zones. The authors believe that HRCT best demonstrates this characteristic location of small rounded areas of attenuation associated with dilated airways.

Adult

Importance of hydrolysis of amino acid moiety in water-soluble prodrugs of disodium cromoglycate for increased oral bioavailability.

The relationship between physicochemical properties and oral absorption was investigated in prodrugs for the oral delivery of disodium cromoglycate (DSCG). To improve the lipophilicity of DSCG, various lipophilic moieties were introduced into the twin carboxyl groups. However, this did not lead to improved oral absorption in rabbits because of loss of water solubility, in spite of improved lipophilicity. Water-soluble prodrugs, in which an amino acid was introduced into a hydroxy group by ester linkage in addition to ethyl residues at twin carboxyl groups of DSCG, were synthesized and examined for oral absorption in rabbits and rats. The oral absorption of these prodrugs was affected by the species of amino acids introduced as a water-soluble moiety. Therefore, we examined the relation between the oral absorption of water-soluble prodrugs and the hydrolysis rate of the amino acid moiety. A good linear correlation was obtained between the oral absorption and the hydrolysis rate constant catalyzed by digestive enzymes, trypsin or alpha-chymotrypsin. It was thus concluded that the amino acid moiety of water-soluble prodrugs must be rapidly hydrolyzed to a permeable lipophilic prodrug still possessing the ethyl moiety at twin carboxyl groups in the small intestinal tract for good oral absorption.

Administration, Oral

Characteristics of 1,3-bis-(2-ethoxycarbonylchromon-5-yloxy)-2-((S)- lysyloxy)propane dihydrochloride (N-556), a prodrug for the oral delivery of disodium cromoglycate, in absorption and excretion in rats and rabbits.

The absorption and excretion of 1,3-bis-(2-ethoxycarbonylchromon-5-yloxy)-2- ((S)-lysyloxy)propane dihydrochloride (N-556), which is a prodrug for the oral delivery of disodium cromoglycate (DSCG), were studied in rats and rabbits. In both animal species, the plasma concentration of DSCG after oral administration of N-556 peaked within 1.0 h, and thereafter declined with a half-life of about 1.2 h in rats and rabbits. The area under the plasma DSCG level versus time curve (AUC) increased in proportion to the dose of N-556 in both animals. The bioavailability of N-556 as calculated from AUC was about 6% in rats and 40% in rabbits, whereas that of DSCG was only 0.1% in rats and 2.5% in rabbits. About 2% and 15% of the dose were respectively excreted as DSCG in the urine and bile after the oral administration of N-556 in rats. The ratio of biliary excretion to urinary excretion (B/U) after the oral administration of N-556 was about twice that after the intravenous injection of DSCG. In rabbits, the urinary and biliary excretions of DSCG after oral administration of N-556 were about 25% and 5%, respectively. The B/U ratio after the oral administration of N-556 in rabbits was similar to that after intravenous administration of DSCG. The difference in the systemic bioavailability of N-556 between rats and rabbits thus appears to be due to a first-pass effect, in addition to a difference in the absorption rate.

Absorption

Bronchiolitis obliterans organizing pneumonia. Clinical features and differential diagnosis.

The clinical features of 34 Japanese patients with bronchiolitis obliterans organizing pneumonia (BOOP) are discussed. Thirty-two patients (94 percent) had symptoms of cough, fever, or dyspnea. On chest roentgenograms, bilateral patchy infiltrates were seen most frequently in 23 patients (68 percent), followed by small linear opacities in five (15 percent), both patchy infiltrates and reticulonodular opacities in four (12 percent), and reticulonodular opacities in two (6 percent). The bronchoalveolar lavage fluid (BALF) cell findings obtained from 26 patients revealed an increase in the percentage of lymphocytes in 20 patients (77 percent), neutrophils in 15 (58 percent), and eosinophils in 16 (62 percent), and a decrease in the CD4+/CD8+ ratio in 14 of 23 patients (61 percent). Corticosteroids were administered to 25 patients. Except for one patient who died, the prognosis was good in all patients. Further, in patients without corticosteroid therapy, the prognosis was good.

Adrenal Cortex Hormones

Response to oral corticosteroid in patients with chronic obstructive pulmonary disease.

We studied the effect of 30 mg of prednisolone on 29 Japanese patients with chronic obstructive pulmonary disease (COPD). The mean value of the baseline forced expiratory volume in one second (FEV1; mean +/- SEM) was 1.14 +/- 0.12 l (46.9 +/- 3.9% pred) and the FEV1 following the steroid trial was 1.30 +/- 0.12 l (53.7 +/- 4.3% pred). Post-trial FEV1--baseline FEV1/predicted FEV1 was 6.8 +/- 1.9%. Five patients (17%) had more than a 15% increase in FEV1 as a percentage of predicted FEV1. Post-trial FEV1/baseline FEV1 was 117.3 +/- 4.3%, and 12 patients (41%) had more than a 20% increase in FEV1 after the trial. Acute bronchodilator response to beta-agonist correlated positively with the response to corticosteroid. Baseline spirometries, blood eosinophil counts, serum IgE levels, sputum eosinophil counts, family history of asthma, and history of paroxysmal dyspnea did not vary across responders and non-responders. Patients with severe COPD should be treated to achieve the best possible pulmonary functions indicated by a steroid trial within the limit of acceptable levels of adverse effects.

Aged

Heterotopic intestinal membrane in a retroperitoneal tumor.

Plain abdominal X-rays of a 13-year-old girl with chief complaints of back pain revealed calcification in the upper left abdomen. A calcified tumor was confirmed at the dorsal side of the pancreatic tail upon admission. A completely formed colic membrane free of all other germ layers was discovered within the tumor, leading to a diagnosis of heterotopic colonic membrane. To our knowledge, there have been no other cases of heterotopic intestinal tissue of this type, so we consider this an extremely rare case worth reporting.

Adolescent

Effects of cyclic and continuous total enteral nutrition on 24-h rhythms of body temperature and urinary excretions.

To clarify the relationship between the pattern of diet intake and circadian rhythm in man, we measured body temperature and urinary excretions at 4-h intervals over a 24-h period in 18 patients who were in vegetative states and had been receiving total enteral nutrition (TEN) for at least 4 weeks. One group of patients was given a liquid diet intraduodenally and continuously throughout a day (continuous TEN), whereas the two other groups received their daily enteral feeding during a restricted time of day, either in the daytime from 0800 h to 2000 h (diurnal TEN) or in the nighttime from 2000 h to 0800 h (nocturnal TEN). In the diurnal TEN group, there was a clear body temperature rhythm with a peak at 2000 h, whose pattern was similar to the well-established body temperature rhythm in normal subjects. The nocturnal TEN group also showed a temperature rhythm, but the peak appeared at 0400 h. The continuous TEN group did not show any consistent body temperature rhythms. These effects of the schedule of TEN were quite similar to those on the circadian cortisol rhythm reported previously (J. Nutr. Sci. Vitaminol., 35, 639-647, 1989). In contrast to the body temperature rhythm, the rhythm of urinary excretions of water, sodium and potassium was little influenced by the schedule of TEN, showing a normal pattern with more excretions during the daytime in every group. Essentially the same effects were confirmed in a patient who received the three schedules of TEN in rotation for 5 weeks of each schedule.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged

[Usefulness of MR angiography in renal tumor].

MR angiography using a gradient-echo, pulse sequence FLASH (fast, low-angle shot) method during breath-hold with a "MAGNETOM H-15" scanner (1.5 Tesla; Siemens Medical System) was performed on 27 patients with renal tumor at our clinic between February 20, 1990 and September 30, 1991 and we studied to evaluate its usefulness. Of these 27 patients, 22 patients including one patient under hemodialysis treatment had renal cell carcinoma and one patient had oncocytoma pathologically proven from the excised specimens. The remaining four patients including two patients associated with inferior vena caval tumor thrombus were clinically diagnosed as renal cell carcinoma based on the result of imaging examinations such as excretory urography, ultrasonography, computed tomography and conventional angiography. However, they could not be operated on because their tumors were too advanced. By reconstruction of the data of consecutive coronal scans of the abdomen with Maximum Intensity Projection (MIP), the MR angiography could in all cases delineate abdominal blood vessels such as the abdominal aorta, inferior vena cava and renal arteries and veins simultaneously without any intravenous contract materials. Our present study revealed that MR angiography has some advantages, especially with regard to preoperative angiographic information about the abdomen of patients with renal tumor. That is, MR angiography can delineate many kinds of arteries and veins of the abdomen simultaneously and in a broader range, as well as it can be performed on the patients with hypersensitivity to iodinated contrast materials or renal insufficiency in a usual fashion.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma

[Renal kallikrein-kinin system].

The renal kallikrein-kinin system seems to participate in the regulation of blood pressure, control of sodium and water excretion, renal vascular resistance and renin release. By using ultrastructural immunocytochemistry, in situ hybridization or polymerase chain reaction experiments with the appropriate cDNA probes, kallikrein and kininogen were observed to exist and be synthesized in different types of cells of the nephron. Recently, new finding of a kinin receptor has been reported, since specific kinin receptor antagonists have become available. The localization of components of kallikrein-kinin system in the kidneys and its relation to renal function is discussed.

Animals

RFLP analysis in the TNF-beta gene and the susceptibility to alloreactive NK cells in Behçet's disease.

Behçet's disease is known to be associated with HLA-B51. To address the possibility that a non-human leukocyte antigen (HLA) gene closely linked to the HLA-B gene, such as tumor necrosis factor (TNF)-alpha, TNF-beta, or ECl (the locus that determines the susceptibility to alloreactive natural killer [NK] cells), is involved in the susceptibility to Behçet's disease, NcoI and EcoRI restriction fragment length polymorphisms in the TNF-beta gene and the susceptibility to lysis by alloreactive NK cells were investigated in Behçet's patients. In our NcoI restriction fragment length polymorphism (RFLP) analysis in the TNF-beta gene, the frequency of the NcoI 5.5 kb homozygote was decreased considerably in the patients, especially those with the ocular lesions, in relation to the healthy controls. However, no significant difference was observed between these groups in the EcoRI RFLP band distribution in this gene or the in susceptibility to lysis by alloreactive NK cells. These results indicated that a non-HLA gene located around the TNF gene region centromic of the HLA-B gene was a candidate to control the genetic susceptibility to Behçet's disease.

Base Sequence

[Urinary N-acetyl-beta-D-glucosaminidase and gamma-glutamyl-transpeptidase activities for evaluation of renal disturbance in patients with multiple myeloma].

The activities of N-acetyl-beta-D-glucosaminidase (NAG), gamma-glutamyl-transpeptidase (gamma-GTP) and NAG isoenzyme were measured in the urine of 20 patients with multiple myeloma (IgG/IgA type/Bense Jones type; 15/1/4 cases) and 25 healthy controls to evaluate these activities as indicators of renal disturbance in multiple myeloma. NAG isoenzyme fractions in urine were measured by agarose electrophoresis-m-cresol sulfonphthaleinyl-NAG reaction. Mean urinary NAG activity in the patients with myeloma was significantly higher than that in the controls (20.1 +/- 3.3 vs 4.3 +/- 0.3U/g. cr; p < 0.001). Urinary NAG activity in these patients correlated positively with the dose (mg/g. cr) of urinary protein (r = 0.755; p < 0.01), most of which were considered to be light chain protein, but not with creatinine clearance. Each urinary NAG isoenzyme fraction (NAG-1, -2, -3) was higher in the patients than that in the controls, and especially NAG-2 fraction (A form) showed a highly positive correlation with the dose of urinary protein. Urinary gamma-GTP activity in the patients did not differ from that in the controls, but urinary NAG/gamma-GTP ratio was higher in the patients, and reversely correlated with creatinine clearance (r = -0.721; p < 0.01). It is suggested that the elevation of urinary NAG activity results from the damage of lysosome in proximal tubular cells by urinary light chain protein and its degradation products. Therefore, urinary NAG activity may be a good index for proximal tubular disturbance, and NAG/gamma-GTP ratio may be an index for the extensive damage of nephrons in addition to the damage of tubular cells in multiple myeloma.

Acetylglucosaminidase

[A case of aortic valve stenosis and regurgitation with idiopathic thrombocytopenic purpura].

A patient of aortic valvular disease with idiopathic thrombocytopenic purpura underwent aortic valvular replacement. We report a preventive measure against the intra and postoperative bleeding. The patient was a 67-year-old man. He was diagnosed as aortic valvular stenosis with regurgitation. There was no abnormal data about the coagulation test. Thrombocyte count was 8.2 x 10(4)/mm3, but thrombocytopenic life span had shortened 3.8 days. So, we used gamma-globulin 400 mg/kg/day for 5 days before the day of operation and infused blood platelets on the day of operation. There was no problem intra and postoperative period. On the 14th postoperative day thrombocyte count increased to 22.9 x 10(4)/mm3, and thrombocytopenic life span returned to normal range (7.6 days). But on the 45th day of postoperation, thrombocyte count decreased to 11.0 x 10(4)/mm3. We think that many gamma-globulin medication is a useful method to prevent intra and postoperative bleeding resulting from idiopathic thrombocytopenic purpura.

Aged

[A comparison of bronchodilating drugs in the treatment of stable COPD].

The purpose of this study was to establish the optimal bronchodilating drug among therapies currently available for clinical treatment of the stable phase of chronic obstructive pulmonary disease (COPD). The efficacy of ipratropium bromide 40 micrograms, salbutamol 200 micrograms, and ipratropium bromide 40 micrograms plus salbutamol 200 micrograms was compared in 14 patients with COPD. Daily PEFR was obtained during the last seven days of a 2 week period incorporating drug inhalation four times daily. FEV1 and FVC were assessed on the final day of the treatment period. In the absence of bronchodilating medication, FEV1 was 1.27 +/- 0.13 l (52.9 +/- 5.1% pred). With ipratropium bromide 40 micrograms alone, FEV1 was 1.43 +/- 0.13 l (59.8 +/- 5.3% pred). A similar value was obtained for salbutamol 200 micrograms: 1.45 +/- 0.14 l (61.0 +/- 5.4% pred). However, FEV1 following the administration of ipratropium bromide 40 micrograms in combination with salbutamol 200 micrograms was 1.51 +/- 0.13 l (63.6 +/- 5.3% pred). The percent increase in FEV1 (compared to the value obtained without medication) was significantly higher with combined ipratropium bromide 40 micrograms plus salbutamol 200 micrograms (122.2 +/- 3.8%) than with either ipratropium bromide 40 micrograms (114.8 +/- 5.5%) or salbutamol 200 micrograms (116.5 +/- 4.4%) alone. Furthermore, the daily post-dilator PEFR improved significantly more with the combined therapy four times a day (311 +/- 29 l/min) than with either ipratropium bromide 40 micrograms (296 +/- 30 l/min) or salbutamol 200 micrograms (303 +/- 29 l/min) therapy alone. There was no discernible difference between results obtained with ipratropium bromide 40 micrograms versus salbutamol 200 micrograms.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation

[Acute lymphoblastic leukemia with extensive demyelinated lesion of the brain stem during complete remission].

A case of acute lymphoblastic leukemia (ALL) which showed extensive demyelinated lesion of the brain stem during complete remission is presented. A 13 year-old girl who was diagnosed as ALL in February, 1987 was treated according to the TCCSG L84-11 protocol, which induced complete remission in June, 1987. Her condition had been stable until April, 1988 when she abruptly complained of gait disturbance, vertigo and anorexia. She was subsequently admitted to our hospital. At the time of admission, she had ataxic gait, horizontal nystagmus towards right at dextroversion, bilateral exaggerated patellar tendon reflex, emotional incontinence, urinary incontinence and left 6th and 7th nerve palsy. In the middle of May, right spastic hemipalesia and hypesthesia became apparent. Left caudal pontine-basal lesion was suspected and was confirmed by MRI. Her synptoms progressed. Five months after admission, suffered repeated central apnea and died. Autopsy disclosed extensive cervical spinal cord. Cerebrum and cerebellum were intact. No evident findings suggesting the etiology were obtained. Whole skull radiation, intrathecal methotrexate, cytosine arabinoside and hydrocortisone might have contributed to the development of the demyelinated lesion.

Adolescent