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Biomedical subjects

K Nishimura

Publications and source records attributed to K Nishimura.

At least 487 records · Page 27Linked to original sources

CT and pathological correlation of pulmonary sarcoidosis.

In CT the presence of mediastinal or hilar lymphadenopathies and thickened bronchovascular bundles are landmarks for the diagnosis of pulmonary sarcoidosis. The major CT findings for parenchymal involvement are thickened bronchovascular bundles, large parenchymal nodules, pleural or subpleural nodules, ground-glass opacities, local lung volume loss (distortion of the lung parenchyma), and microscopic and macroscopic honeycombing. The thickened bronchovascular bundles correspond histologically to granulomas, either with or without perigranulomatous fibrosis in the connective tissue sheath around the pulmonary vessels and airways. Conglomerate granulomas are represented on CT by high-attenuation nodules, and the ground-glass opacities are caused by the summation of a number of small granulomas in the interstitium.

Adult↗

Right ventricular function evaluated by volumetric analysis during left heart bypass in a canine model of postischemic cardiac dysfunction.

Right ventricular function during left heart bypass was evaluated by volumetric analysis with a conductance catheter in 12 dogs with postischemic cardiac dysfunction. The conductance catheter was used to assess the volumetric status of the right ventricle and thereby allowed a right ventricular pressure-volume curve to be obtained, in which transient volume loading on the right ventricle was applied. The following right ventricular properties during left heart bypass were assessed and compared with properties measured without left heart bypass, by means of load-independent parameters: maximum elastance, stroke work/end-diastolic volume relation, end-diastolic pressure/volume relation, and stroke work/end-diastolic pressure relation. The stroke volume derived from the conductance catheter and the electromagnetic flow probe showed good linear correlation (r2 = 0.733 to 0.975). After initiation of left heart bypass, maximum elastance did not change significantly, although volume intercept significantly increased, from 1.2 +/- 7.3 to 3.6 +/- 7.9 ml (p < 0.05). End-diastolic pressure/volume relation was well fitted to the exponential curve (EDP = e(k1.EDV+k2)) and was shifted to the right and downward during left heart bypass; the slope k1 significantly decreased, from 0.12 +/- 0.06 to 0.10 +/- 0.07 (p < 0.01). Stroke work/end-diastolic volume relation and stroke work/end-diastolic pressure relation were closely fitted to the linear regression, and their slopes were significantly increased during left heart bypass, from 0.14 +/- 0.08 to 0.18 +/- 0.08 (p < 0.05) and from 0.22 +/- 0.15 to 0.34 +/- 0.19 (p < 0.01), respectively. These results suggest that the decompression of the left ventricle and septal shifting by left heart bypass provide good diastolic compliance and good systolic performance because of afterload unloading of the right ventricle. Thus the left heart bypass improved the overall right ventricular performance, particularly at higher end-diastolic pressures, in dogs with postischemic cardiac dysfunction.

Animals↗

Evaluation of serum KL-6 levels in patients with pulmonary tuberculosis.

SETTING: KL-6, a human MUC-1 mucin preferentially expressed on type II pneumocytes, is a sensitive serum marker for evaluating alveolar damage of interstitial pneumonia and pulmonary fibrosis. Some patients with pulmonary tuberculosis develop severe respiratory dysfunction caused by extensive pulmonary fibrosis, compensatory emphysema and fibrous pleural thickening. OBJECTIVE: To evaluate the clinico-pathological significance of KL-6 in pulmonary tuberculosis. DESIGN: Serum KL-6 levels were measured in sera from 57 patients with active pulmonary tuberculosis and 38 healthy controls by a sandwich-type enzyme-linked immunosorbent assay. Immunohistochemistry was performed by an avidin-biotin-peroxidase complex method. RESULTS: KL-6 levels were significantly higher in the patients than in the healthy controls (518 +/- 693 [SD] vs 227 +/- 91 U/ml, P < 0.001) and increased significantly according to the extent of pulmonary lesions evaluated by chest X-ray (P < 0.001). There was a significant negative correlation between serum KL-6 levels and % vital capacity (VC) (r = 0.642, P < 0.05). KL-6 was strongly expressed on proliferated type II pneumocytes and cuboidal epithelial cells adjacent to thickened intralobular septa and pleura. CONCLUSIONS: In pulmonary tuberculosis, serum KL-6 originates from proliferated type II pneumocytes and cuboidal epithelial cells, and is a useful marker presenting the degree and extent of pulmonary fibroproductive lesions.

Aged↗

Two-dimensional intravenous coronary arteriography using above-K-edge monochromatic synchrotron X-ray.

RATIONALE AND OBJECTIVES: For intravenous (i.v.) coronary arteriography, a real-time two-dimensional (2D) imaging system is being developed using above-K-edge monochromatic X-rays alone. The potential diagnostic value of this system was examined in the current study. METHODS: The angiographic system consisted of an asymmetric silicon (311) monocrystal, an image intensifier, and a charged-coupled device camera. It was constructed at the beam line of the Tristan Accumulation Ring. Monochromatic X-rays of 33.32 keV were used, and each image was recorded over 2 msec. RESULTS: Ventricular wall motion and the anatomy of the coronary arteries could be seen in dogs by sequential images obtained without subtraction. The left anterior descending coronary artery, left circumflex coronary artery, and right coronary artery and the branches of these vessels were observed. The parts of the coronary arteries overlapping the aorta and left ventricle were revealed somewhat during washout of the contrast material. CONCLUSION: For a 2D imaging system, monochromatic i.v. coronary angiography using an energy above the iodine K-edge might be able to image the coronary arteries without subtraction. However, the image quality needs to be improved by increasing the X-ray flux, decreasing background radiation scatter from the object, and decreasing contamination with 99-keV X-rays.

Animals↗

The role of surgery in advanced neuroblastoma.

Recently we performed multi-modal therapy including chemotherapy with bone marrow transplantation (BMT), surgery, and local irradiation in the treatment of advanced neuroblastoma. As a result, all Stage III patients survived, and 4 out of 8 Stage IV patients who underwent our original systemic gross complete resection achieved long-term survival, 4y8m, 5y8m, 5y6m and 5y5m, respectively. Long-term survival patients were treated by local irradiation, brain surgery and intensive induction chemotherapy before primary site operation, and when resolution of distant metastases was obtained, the primary site was resected completely, followed by postoperative supralethal chemotherapy with BMT. The purpose of this report is to elucidate the role of surgery in advanced neuroblastoma based on our clinical results.

Bone Marrow Transplantation↗

Overcoming the metastasis-enhancing potential of human tumor necrosis factor alpha by introducing the cell-adhesive Arg-Gly-Asp sequence.

A mutein, F4168, of human tumor necrosis factor alpha (hTNF-alpha) containing the cell-adhesive Arg-Gly-Asp (RGD) sequence near the N terminus was constructed. In contrast to hTNF-alpha, the mutein had binding activity to B16F10/L5 melanoma cells similar to that of fibronectin or laminin, indicating that the adhesive nature of the RGD sequence is conferred upon hTNF-alpha. Introduction of the RGD sequence did not alter the antitumor potential of hTNF-alpha. Simultaneous injection of F4168 and B16F10/L5 melanoma cells into mice did not enhance metastasis formation in lungs, whereas hTNF-alpha significantly promoted it. Enhancement of spontaneous lymph node metastasis of B16F10/L5 cells was also evident in TNF-alpha- but not in F4168-treated mice. In the spontaneous lymph node metastasis model of MethA fibrosarcoma, F4168 injection inhibited metastasis formation more effectively than hTNF-alpha. B16F10/L5 melanoma cells treated with hTNF-alpha enhanced not only their binding activity to laminin but also their invasive potential into Matrigel, whereas F4168 showed no such enhancement. These results suggest that F4168 is a low-toxicity mutein of hTNF-alpha.

Amino Acid Sequence↗

Novel mutein of tumor necrosis factor alpha (F4614) with reduced hypotensive effect.

To eliminate systemic toxicity, including the hypotension associated with human tumor necrosis factor alpha (TNF-alpha), we constructed mutant proteins (muteins) by mean of genetic engineering. A novel mutein, F4614, containing mutations of 5Thr-->Gly and 6Pro-->Asp, which resulted in the introduction of cell-adhesive Arg-Gly-Asp and 29Arg-->Val, had remarkably reduced hypotensive effects and lower lethality. We present evidence that the Arg-->Val mutation at position 29 is largely responsible for the reduced hypotensive effect. This effect of F4614 was thought to be closely correlated with its low inducibility of nitric oxide and prostaglandin E2 in vivo. In addition, the therapeutically effective dose of F4614 to MethA fibrosarcoma-transplanted mice was increased compared with that of TNF-alpha, indicating a wide therapeutic index. These results indicated that F4614 has several advantages as a systemic therapeutic drug in the treatment of cancer.

Amino Acid Sequence↗

Cloning and identification of the hemG gene encoding protoporphyrinogen oxidase (PPO) of Escherichia coli K-12.

Cells of the VSR751 strain, which was previously isolated as a photoresistant revertant of the visA-deleted (hemH-deleted) strain of Escherichia coli K-12, accumulated uroporphyrin (uro), coproporphyrin (copro) and protoporphyrin IX (proto), but did not accumulate as much protoporphyrin as cells of the parental strain (hemH-deleted). Therefore, we concluded that strain VSR751 must be defective in protoporphyrinogen oxidase (PPO), the product of the hemG gene. By complementation analysis using VSR751, we isolated and identified this gene. The hemG gene is located at 86 mim on the E. coli chromosome, just upstream of the rrnA operon, and is transcribed clockwise in the same direction as the rrnA operon. This gene encodes a 181-amino acid protein with a calculated molecular mass of about 21 kDa. Sequence analysis revealed the presence of flavodoxin motif, suggesting tha a cofactor of this enzyme is flavin mononucleotide, which is consistent with the previous report that the mammalian PPO had the flavin cofactor.

Amino Acid Sequence↗

Outbreak of pertussis in highly immunized adolescents and its secondary spread to their families.

An outbreak of pertussis was recognized in a highly immunized sixth-grade class of schoolchildren. Among 43 children aged 11-12 years in the class, 38 had been immunized with three doses or more of DTP containing whole-cell pertussis vaccine, two with two doses of DTP and three children were unimmunized. The last DTP vaccines had been given 6-10 years before the outbreak. A total of eight children with pertussis suffering paroxysmal coughing attacks for 3 weeks or more were identified, seven being fully immunized and one unimmunized. Among the eight cases, two were confirmed by both culture and serology and one by serology alone. The attack rate in fully immunized children was 18.4% (7/38). Secondary spread of pertussis was identified in five of the households from which the eight patients originated. A total of six cases of pertussis from these five households were identified, and two of these were culture-confirmed. These observations suggest that vaccine-induced immunity weakens considerably 6-10 years after vaccination, and that booster immunization with DTP instead of DT is therefore recommended for the control of pertussis.

Child↗

A case report of Stevens-Johnson syndrome with Mycoplasma pneumoniae infection.

We encountered an 8 year old boy who suffered from Stevens-Johnson syndrome with Mycoplasma pneumoniae infection. He had multiple erythema with vesicles in oral mucosa, and on his palms and feet, trunk and genital regions. We treated him with prednisolone (1 mg/kg per day) and antibiotics. His skin lesions improved dramatically, and a persistent fever and toxic general condition also showed dramatic improvement. Although the use of corticosteroids for Stevens-Johnson syndrome has recently been controversial, we thought that administration of corticosteroids was an effective treatment for some selective cases of Stevens-Johnson syndrome. The patient reported in this study had many beneficial effects in response to corticosteroid treatment.

Cefamandole↗

Recent studies of the centrifugal blood pump with a magnetically suspended impeller.

We have been developing a centrifugal blood pump with a magnetically suspended impeller. To improve pump efficiency, we investigated the pump performances of many kinds of impeller vanes and diffusers, as well as the flow in the gap between the impeller discs and the pump housing. We found the vanes and the diffusers with high pump efficiency; however, high efficiency does not mean low hemolysis. It seems important to prevent generation of small-sized eddies with high shear stress. Hemolysis tests are carried out to find the optimal vane profile and gap clearance. The index of hemolysis and temperature change of our pump is better than those of the Biopump. Short-term in vivo studies show that the layer of white thrombi adheres to the machined rough surface of polycarbonate, which composes the narrow gap (0.2 mm) between the impeller and the pump wall, but a smooth surface coated with silicon prevents adhesion of that layer.

Animals↗

[Epidemic of influenza in Kyushu-Okinawa District (April 1994-March 1995)].

The prevalence of influenza in Kyushu-Okinawa District in April 1994- March 1995 was studied as the prevalence of influenza virus, to determine the sero-type of influenza viruses isolated in Kyushu- Okinawa District prefectures and cities. As a result, three sero-types of influenza viruses, i.e. type A/H1N1, type H3N2 and type B, were isolated in Kyushu-Okinawa District in this season, but most of the isolates were type A/H3N2 and type B. Weekly changes of reported influenza patients and period of virus isolation at local public health institutes revealed that influenza epidemics of the earlier part in this season was caused by type A/H3N2 and the latter part due to type B. Type A/H3N2 spread all over Kyushu-Okinawa District in a shorter period (about 2 weeks) through the westside of Kyushu and down south, and type B stayed about one month in northern Kyushu and took about 7 weeks to spread all over Kyushu-Okinawa District. Based on these results, the spread of influenza virus in Kyushu-Okinawa District was visualized on the isopleth maps.

Disease Outbreaks↗

Comparative dose-response study of three anticholinergic agents and fenoterol using a metered dose inhaler in patients with chronic obstructive pulmonary disease.

BACKGROUND: Inhaled anticholinergics and beta agonists are widely used in the treatment of patients with chronic obstructive pulmonary disease (COPD). However, dosage requirements have not been thoroughly evaluated and comparative dose-response data for these agents are limited. METHODS: Twenty men with stable COPD of mean (SD) age 69.4 (5.8) years and FEV1 0.93 (0.38) litres were studied in randomised, double blind, crossover, placebo controlled experiments. All of the patients received two, four, eight, and 16 puffs of ipratropium bromide (20 micrograms/puff), flutropium bromide (30 micrograms/puff), oxitropium bromide (100 micrograms/puff), fenoterol (200 micrograms/puff), or placebo in random order on five separate days. Doses were administered by a metered dose inhaler at intervals of 60 minutes to give cumulative doses of two, six, 14, and 30 puffs. Five mg of nebulised salbutamol was administered 60 minutes after the patient had received the final 16 puffs of each regimen. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), heart rate, and blood pressure were measured five minutes before each treatment and 30 minutes after treatment with nebulised salbutamol. RESULTS: FEV1 and FVC reached a plateau after administration of a cumulative dose of 14 puffs of ipratropium bromide (280 micrograms) or flutropium bromide (420 micrograms), and after six puffs of oxitropium bromide (600 micrograms). There were no differences with respect to maximum increases in FEV1 and FVC amongst the three anticholinergic agents. However, after six puffs oxitropium bromide produced a greater increase in FEV1 than either ipratropium bromide or flutropium bromide. Fenoterol caused a greater increase in both FEV1 and FVC than the three anticholinergic agents after six puffs, as well as a greater increase in pulse rate. Oxitropium bromide produced a greater increase in pulse rate than the other anticholinergics after 14 puffs. The incidence of side effects was dose-related and notable adverse effects were reported after 30 puffs of ipratropium bromide, 14 puffs of oxitropium bromide, and two puffs of fenoterol. CONCLUSIONS: Oxitropium bromide produced a greater bronchodilator effect than either ipratropium bromide or flutropium bromide when used at doses of less than six puffs, without apparent side effects. There were, however, no differences in maximal response between these drugs. Fenoterol may have a greater peak bronchodilator effect than the anticholinergic agents but it causes more adverse effects, even at lower doses. Depending upon the balance between efficacy and side effects, oxitropium bromide may be preferred in the treatment of patients with COPD.

Aged↗

Effect of acupuncture at the Hoku point on vibration-induced finger flexion reflex in man: comparison between press needle technique, electroacupuncture, and in-situ technique.

Effects of press needle technique (PN), electroacupuncture (EA), or in-situ technique (IS) on vibration-induced finger flexion reflex (VFR) were examined in 31 healthy adults. VFR, which is tonic finger flexion evoked by vibration applied to the finger tip, was induced by vibrating the volar side of the middle finger tip before and after acupuncture. Acupuncture was applied to the Hoku point on both sides. The three techniques, each studied on separate days, inhibited VFR and there was no significant difference in VFR inhibition among the three techniques (percentage of pre-acupuncture VFR was 71.5 +/- SE 2.2% after PN, 72.6 +/- SE 2.4% after EA, and 75.6 +/- SE 2.8% after IS). The results suggest that afferent signals from muscles contracting due to electrical stimulation had no significant effect on the reflex arcs of VFR; and that the intradermal stimulation by acupuncture played a significant role in VFR inhibition.

Acupuncture Therapy↗

Clinicopathological study on upper urinary tract tumors and associated bladder tumors.

We reviewed 82 patients with 83 upper urinary tract tumors and investigated those who had associated bladder tumors. Of these patients, 7 (9%) had previous bladder tumors, 14 (17%) had concurrent bladder tumors, and 18 (22%) subsequently developed bladder tumors. As 1 patient subsequently developed a bladder and a upper urinary tract tumor at different times, 38 patients (46%) had associated bladder tumors. The time interval between the occurrence of a previous bladder tumor and the subsequent upper urinary tract tumor was 11 to 144 months (mean: 41 months), while that between an upper urinary tract tumor and the subsequent bladder tumor was 3-31 months (mean: 12 months). Most of the previous bladder tumors were papillary, multiple, and noninvasive (pT1 or less). Multiple upper urinary tract tumors were associated with a high incidence of concurrent bladder tumors, while high-grade (G2, G3) or invasive (pT2 or more) upper urinary tract tumors were associated with a high incidence of concurrent and subsequent bladder tumors. Patients with concurrent bladder tumors had a worse prognosis than those with previous or subsequent bladder tumors due to the increased incidence of high-stage tumors at either the upper tract or bladder site. Our findings suggest that tumor cell implantation is a possible mechanism for the recurrence of bladder tumors and upper urinary tract tumors.

Adult↗

Pulmonary lymphangioleiomyomatosis: a report of 46 patients including a clinicopathologic study of prognostic factors.

The clinical and pathologic features of 46 patients from Japan, Korea, and Taiwan with pulmonary lymphangioleiomyomatosis (LAM) were studied. Only two (5%) among 40 evaluable treatments were assessed to be effective. Some prognostic factors of LAM were recognized. A reduction of the forced expiratory volume in one second/forced vital capacity (FEV1/FVC) ratio was a poor prognostic factor at 2 yr after the first examination, with a statistically significant difference (p < 0.05). An increase in the percentage of predicted total lung capacity (%TLC) correlated with a poor prognosis at 2, 3, and 5 yr after the first examination, with statistically significant differences (p < 0.05). Histologically, two types of pulmonary lesions were observed; a predominantly cystic type and a predominantly muscular type. Patients with predominantly cystic LAM lesions showed a tendency to a poor prognosis from 2 to 5 yr after the biopsy. Among open lung biopsy findings, higher grades of abnormal areas were unfavorable as a prognostic factor from 2 to 5 yr after the biopsy, with statistically significant differences (p < 0.05). Higher grades of cystic lesions correlated inversely with survival at 2, 4, and 5 yr after the lung biopsy, with statistically significant differences (p < 0.05).

Adult↗

Surface-coil magnetic resonance imaging of the internal auditory canal and the inner ear. Preliminary report.

Parasagittal surface-coil magnetic resonance imaging of the internal auditory canal and the inner ear was performed. We used T2-weighted fast spin-echo sequences to visualize the inner ear and the individual nerves in the internal auditory canal with high contrast in a short acquisition time. Computer-assisted quantitative measurement of the nerves was performed to estimate the cross-sectional areas and the diameters of the nerves. The average diameters of the facial nerve, the cochlear nerve, and the vestibular nerve of normal-hearing individuals were, respectively, 1.1 +/- 0.2 mm (mean +/- SD), 1.2 +/- 0.2 mm, and 1.5 +/- 0.2 mm. In the cerebellopontine angle, the average diameter of the eighth nerve was 1.8 +/- 0.2 mm. Two patients with unilateral and bilateral hearing loss were also presented. In the patient with unilateral deafness, the cochlear nerve of the diseased side was not identified and the eighth cranial nerve diameter was smaller than that of the normal side. In the patient with bilateral deafness, fibrosis of the inner ear and atrophy of the eight nerve were demonstrated in the ear with posttraumatic deafness. The present method may represent a new approach to the assessment of pathologic processes involving the inner ear and the nerves in the internal auditory canal.

Adult↗

N-Alkylphthalimides: structural requirement of thalidomidal action on 12-O-tetradecanoylphorbol-13-acetate-induced tumor necrosis factor alpha production by human leukemia HL-60 cells.

Phthalimide analogs N-substituted with n-butyl, tert-butyl, hexyl and adamantyl groups were designed and prepared as simplified analogs of thalidomide and methylthalidomide. All the compounds prepared except N-n-butylphthalimide showed thalidomidal activity on 12-O-tetradecanoylphorbol-13-acetate-induced tumor necrosis factor (TNF)-alpha production by human leukemia HL-60 cells. Among the investigated compounds, including thalidomide and methylthalidomide, N-adamantylphthalimide showed the most potent TNF-alpha production-enhancing activity.

Humans↗