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Biomedical subjects

T Okubo

Publications and source records attributed to T Okubo.

At least 343 records · Page 19Linked to original sources
PubMed1992

[A case of intrathoracic chest wall type lipoma].

Intrathoracic lipoma is a comparatively rare disease. We have recently experienced a case of intrathoracic chest wall type lipoma associated with Charcot-Marie-Tooth disease. The case was a 16-year-old man, in whom preoperative examination of his foot-drop due to Charcot-Marie-Tooth disease pointed out an abnormal chest shadow. Image diagnosis led to intrathoracic chest wall type lipoma. The tumor was easily resectable and was lipoma pathohistologically as well. The literature presented us with 22 cases of such lipoma, which appeared to be predominant for age not more than 10 and age 41-60 and to occur favorably in postero-superior chest wall. Preoperative diagnosis of the present disease became possible to a certain extent by means of CT, MRI. However, in view of imperfect differentiation between lipoma and liposarcoma, surgical resection should be considered, if possibly. No case of intrathoracic lipoma associated with Charcot-Marie-Tooth disease had been reported in the literature, and the causal relationship there between also remains unknown, but to be further examined.

Adolescent↗
PubMed1992

Effect of thyroid hormone on in vivo contractility of the canine diaphragm.

This study was designed to examine the effects of long-term (4 wk) administration of thyroid hormone on the in vivo contractility of the canine diaphragm. We implanted a pair of piezoelectric crystals chronically in the left crural and costal parts of the diaphragm by a midline laparotomy. Contractility was assessed by changes in the shortening of muscle fibers after twitch stimulation of both the crural and the costal parts of the diaphragm and in the transdiaphragmatic pressure (Pdi) after tetanic stimulation (10 to 100 Hz). As a reference, we also studied the response of the quadriceps femoris. Pretreatment measurements were taken 2 wk after surgery. Then, dogs assigned to the hyperthyroid group were given thyroid powder, 0.6 g/kg/day, orally for 4 wk. The control group was fed a diet without thyroid powder for 4 wk. Serum free-T4 level (RIA) in the hyperthyroid group (n = 9) increased from 0.68 +/- 0.07 to 5.72 +/- 0.95 ng/dl (mean +/- SE) (p less than 0.01). Pdi decreased 30 to 40% at all frequencies (p less than 0.05) except 10 Hz. Twitch shortening of the crural and costal parts, compared with pretreatment state, decreased significantly by 47.7 +/- 13.1 and 48.1 +/- 15.0%, respectively (p less than 0.05). The maximal rate of relaxation became significantly faster, by 63.5% (p less than 0.05), in the crural part, whereas that of the costal part tended to become faster but not to a significant extent. In the quadriceps femoris, although twitch force showed no change, both the maximal rate of contraction and maximal rate of relaxation became faster, and tetanic force decreased. Histologic examination of hyperthyroid dogs showed vacuolization and loss of fiber area of the diaphragm. These observations suggest that thyroid hormone impairs contractility of both the crural and costal parts of the diaphragm similarly, and that the decrease in contractility may be due to a loss of muscle mass and summation impairment of twitch contraction, which differs from that in other skeletal muscles.

Animals↗
PubMed1992

[Surgical analysis of mediastinal lymphangioma--analysis of 7 cases].

Mediastinal lymphangioma is a very rare disease. In this study, we evaluated 7 surgically treated cases of mediastinal lymphangioma. Four males and 3 females with ages ranging from 5 months to 74 years (average 31.4 years) were examined. Four patients were asymptomatic but had abnormal shadows on their chest X-ray. Of the remaining patients, one had hoarseness and another had superior vena cava syndrome and both had dyspnea. The other patient was discovered because of cervical tumor. Multiple lymphangiomas were found in only 2 patients. One patient had 4 tumors and the other had 2 tumors in the mediastinum. Of all lymphangiomas, 2 were found in the superior mediastinum, 2 in the anterior mediastinum, 3 in the median mediastinum and 3 in the posterior mediastinum. All patients had cystic lymphangioma including 1 with capillary lymphangioma and 1 with cavernous lymphangioma. Median sternotomy was performed in 3 of the patients and posterolateral thoracotomy was performed in the remainder. The cervical tumor was removed by local incision. Complete resection of the lymphangiomas was performed and no recurrence was observed after surgery.

Adult↗
PubMed1991

Increase in intracellular calcium induced by stimulating histamine H1 receptors in macrophage-like P388D1 cells.

The addition of histamine to macrophage-like P388D1 cells resulted in a dose-dependent increase in intracellular calcium [Ca2+]i measured by fura-2 in single cells. The maximum level of [Ca2+]i was obtained by addition of 1 x 10(-4) M histamine. The increase was primarily due to release from the intracellular store. The addition of an H1 specific antagonist pyrilamine before histamine treatment inhibited the increase reversibly, while an H2 specific antagonist cimetidine had no inhibitory effect. Histamine also resulted in a dose-dependent increase in cGMP but not in cAMP. These data suggest the existence of histamine H1 receptors in these cells and histamine may have some biological effect on the function of macrophages via [Ca2+]i and cGMP as the second messengers.

Animals↗
PubMed1991

Discordant gene and surface expression of the T-cell receptor/CD3 complex in adult T-cell leukemia cells.

Cell surface expression of the T-cell receptor (TCR)/CD3 complex on the cells from 11 acute type adult T-cell leukemia (ATL) and 4 lymphoma type ATL patients was examined by flow cytometry. Cells from 10 of 11 acute ATL patients were TCR alpha beta+ and CD3+, and their mean fluorescence intensities were low (TCR alpha beta, 25.3-84.6; CD3, 22.8-87.8). Cells from two of four lymphoma type ATL did not express this complex, and the other two were CD3+, TCR alpha beta-. In contrast, the mean fluorescence intensity of the TCR/CD3 complex in cells from a patient with T4 chronic lymphocytic leukemia was not low (TCR alpha beta, 129.9; CD3, 117.1). mRNA expressions of the TCR alpha, beta, and CD3 gamma, delta, epsilon, and zeta chains were examined by Northern blots. ATL cells from two acute and two lymphoma types expressed amounts of this complex equal to or greater than those expressed by T4 chronic lymphocytic leukemia. CD3 delta and TCR beta mRNA in ATL and T4 chronic lymphocytic leukemia cells were equally stable to actinomycin D treatment. The synthesis of CD3 zeta protein by ATL cells was detected by Western blotting assay. On the basis of these findings, we discuss the possible involvement of the TCR/CD3 complex in activation of ATL cells.

Adult↗
PubMed1991

[Determination of bromide ion concentration in urine using a head-space gas chromatography and an ion chromatography--biological monitoring for methyl bromide exposure].

A head-space gas chromatography (GC) and an ion chromatography coupled with a conductive detector (IC) were used to evaluate levels of bromide ion in urine. The GC method followed by methylation with dimethyl sulfate, showed higher accuracy (2.7% of relative standard deviation) and lower minimum detection limit (0.4 mg/l) compared to the IC procedure of those values which were 8.7% and 1.0 mg/l. The correlation coefficient between the analytical results of 15 urinary samples by the two methods was 0.793. The bromide ion concentrations detected in 36 urine samples of workers exposed to methyl bromide were averaged at 13.3 +/- 7.7 mg/l. The average bromide ion of the non-exposed group was 7.1 +/- 2.1 mg/l (n = 6). Exposed methyl bromide concentrations of workers were monitored with passive samplers during their work shifts (8 hr). No significant correlation between exposed methyl bromide and bromide ion concentrations in urine was observed.

Bromides↗
PubMed1991

Work-related bladder cancer risks in male Japanese workers: estimation of attributable fraction and geographical correlation analysis.

One hundred and forty-nine relative risks (RRs) on occupations and bladder cancer were extracted from 27 case-control studies and geometric means were calculated for 27 occupations as summary RRs. Those in high risk occupations, among whom the summary RRs significantly exceeded unity, were found to be petroleum workers (RR = 3.51), dye workers (RR = 3.38), machinists (RR = 2.76), drivers (RR = 2.22), rubber workers (RR = 2.19), printers (RR = 2.12), clothing/tailors (RR = 2.10), wood workers/carpenters (RR = 1.70), miners (RR = 1.68), textile workers (RR = 1.63), mechanics (RR = 1.54), engineers (RR = 1.54), leather workers (RR = 1.49), painters (RR = 1.48) and chemical workers (RR = 1.44). The estimated numbers of male bladder cancers in 1980 in the high risk and other occupations were 820 and 2065 cases, respectively. The estimated number of work-related bladder cancer was 548 cases, the attributable fraction being 19% in active employees and 12% in the entire population. The geographical distribution of male bladder cancer deaths in Japan was positively correlated with the distributions of workers in the transport/communications industry and in tertiary industries including services, wholesale, retail, finance and insurance, whereas it was negatively correlated with the distribution of workers in the agricultural industry. These findings suggest that workers in certain industries may be at high risk of bladder cancer, but lifestyle modification associated with urbanization and industrialization could be an alternative explanation.

Analysis of Variance↗
PubMed1991

In vitro activity of YM133, a new semisynthesized macrolide.

YM133, the 4"-O-(4-methoxyphenyl)acetyltylosin, is a new macrolide. The in vitro activity of YM133 was compared with those of erythromycin, josamycin, and rokitamycin by an agar dilution method. YM133 inhibited 90% of the tested isolates of Streptococcus pneumoniae, Legionella spp., and anaerobic bacteria at less than or equal to 1.56 micrograms/ml. The drug inhibited 90% of erythromycin-resistant staphylococci and Streptococcus pyogenes at less than or equal to 50 micrograms/ml. YM133 showed activity against erythromycin-, josamycin-, and rokitamycin-resistant (MIC greater than or equal to 100 micrograms/ml) strains of staphylococci, streptococci, Bacteroides spp., and Clostridium spp. Enterococci were less susceptible to other YM133-like macrolides. Unlike other macrolides, YM133 showed killing activity, and the MBC/MIC ratios of YM133 for several strains were 1:32, whereas those of erythromycin were 4:1,024. In a time-kill curve study, the reduction of viable cells started within 2 h after the addition of YM133.

Anti-Bacterial Agents↗
PubMed1991

Expiratory muscle fatigue in normal subjects.

We examined expiratory muscle fatigue during expiratory resistive loading in 11 normal subjects. Subjects breathed against expiratory resistances at their own breathing frequency and tidal volume until exhaustion or for 60 min. Respiratory muscle strength was assessed from both the maximum static expiratory and inspiratory mouth pressures (PEmax and PImax). At the lowest resistance, PEmax and PImax measured after completion of the expiratory loaded breathing were not different from control values. With higher resistance, both PEmax and PImax were decreased (P less than 0.05), and the decrease lasted for greater than or equal to 60 min. The electromyogram high-to-low frequency power ratio for the rectus abdominis muscle decreased progressively during loading (P less than 0.01), but the integrated EMG activity did not change during recovery. Transdiaphragmatic pressure during loading was increased 3.6-fold compared with control (P less than 0.05). These findings suggest that expiratory resistive loaded breathing induces muscle fatigue in both expiratory and inspiratory muscles. Fatigue of the expiratory muscles can be attributed directly to the high work load and that of the inspiratory muscles may be related to increased work due to shortened inspiratory time.

Adult↗
PubMed1991

Interpersonal awareness and smoking behavior in the workplace.

A questionnaire survey was conducted in small-scale production companies in Japan to examine "interpersonal awareness" and smoking behavior in the workplace. Interpersonal awareness (IA) of smokers is defined as awareness of other people's presence when smoking. Study participants were 1048 smokers and 744 nonsmokers, contrasted by worksite: office or production. Controlling for selected baseline variables, office work smokers, who smoked more in the workplace than production work smokers (77.4% vs 51.6%, p < .001), had a higher IA in the workplace (75.5% vs 58.9%, p < .001) but did not differ in IA at home (69.7% vs 66.0%). In male smokers of both worksites, degree of IA in the workplace correlated positively with that at home (rs = .36, p < .001, office; rs = .45, p < .001, production), and daily cigarette consumption correlated negatively with degree of IA at home (rs = -.44, p < .001, office; rs = -.17, p < .001, production). A predilection for smoking more at home than in the workplace correlated with higher IA in the workplace for male office smokers (rs = -.21, p < .01). In contrast, a predilection for smoking more at home than in the workplace correlated with lower degree of IA at home for production smokers of both sexes (rs = 20, p < .001, male; rs = .53, p < .05, female). Interpersonal awareness is deemed an important behavioral factor for smoking workers.

Adult↗
PubMed1991

Preferential proliferation of anti-DNA producing cells of NZB mice in NZB.xid recipients.

B cells from autoimmune NZB mice were transferred into unmanipulated non-autoimmune NZB.xid mice. The number of antibody-producing cells against various antigens in recipient mice was monitored at varying time after cell transfer using ELISPOT assay. NZB B cells producing antibody against all antigens we examined were able to proliferate in NZB.xid mice, which supports the idea of polyclonal B cell activation. However, anti-DNA producing cells proliferated most rapidly, and anti-BrMRBC producing cells proliferated more rapidly than B cells of other antigenic specificities. The percentage of anti-DNA producing cells in total immunoglobulin-producing cells increased over time whereas the percentage of anti-ovalbumin producing cells kept the same level. This indicates directly the preferential proliferation of NZB anti-DNA producing cells in NZB.xid mice. The result shows the responsibility of antigen-specific stimulation or activation on autoimmunity in the context of polyclonal B cell activation.

Actins↗
PubMed1991

Acute unclassified leukemia originating from undifferentiated cells with the aberrant rearrangement and expression of immunoglobulin and T-cell receptor genes.

To analyze the development pathways of early hematopoietic cells, we studied the rearrangement and expression of the immunoglobulin (Ig) and T-cell receptor (TCR) genes in 12 patients with acute unclassified leukemia (AUL). Leukemia cells from these patients were negative for myeloperoxidase staining and failed to express B-cell, T-cell, or megakaryocyte associated antigens. The expression of the CD7 antigen, myeloid associated antigens, or both was detected in three patients each. Ig and/or TCR gene rearrangements were detected in seven of the 12 patients, and five had rearrangement of both the Ig and TCR genes. Full length mature TCR gene transcripts were not demonstrated in most of the patients showing TCR gene rearrangements. In contrast, cells from two patients with germline configurations of the Ig and TCR genes tested expressed truncated forms of both Ig and TCR genes. These results suggest that AUL may generally originate from undifferentiated cells with an aberrant rearrangement and/or expression of the Ig and TCR genes.

Acute Disease↗
PubMed1991

[A case of graft-versus-host disease following irradiated fresh blood transfusion].

We reported a case of a fatal graft-versus-host disease (GVHD) which developed in a 65-year-old, male patient which was considered to have been induced by irradiated fresh blood donated by his son after a coronary bypass surgery. Fresh blood was obtained from his relatives, and a 15 Gy irradiation was performed before transfusion. The diagnosis of acute GVHD was made by clinical symptoms and histological examinations of the skin and the bone marrow. He died of sepsis on the 19th post-operative day. The HLA typing of the lymphocytes, revealed that the patient had A 2, A 24, Bw 52, Bw 62, Cw 4, DR 2, and his son had A 24, Bw 52, DR 2. A 24 and Bw 52 were homogeneous making his son histocompatible with one of the patient's haplotype. This might well be attributable to the occurrence of GVHD in this case, meaning that 15 Gy irradiation was not sufficient for the prevention of this disease.

Aged↗
PubMed1991

[Successful management of mycotic abdominal arteriovenous fistula complicated with infective endocarditis--a case report].

A 56-year-old man, who had been febrile for one month, suddenly had severe left foot pain. He also became dyspneic. Embolic occlusion of left femoral artery as well as severe acute aortic regurgitation due to Staphylococcus endocarditis was demonstrated by arteriography and echocardiography. The patient underwent emergency aortic valve replacement and above knee amputation of left foot at the same time. Postoperatively he continued to be hypotensive and, at 6th postoperative day, abdominal vascular bruit was first observed. Aortography revealed left common iliac aneurysm with an arterio-venous fistula. The aneurysm was excised and venous opening of the fistula was oversewn. Aortic end was reconstructed with bifurcated prosthetic graft. Antibiotic therapy was continued 6 weeks. His postoperative course was uneventful.

Aneurysm, Infected↗
PubMed1991

Measurement of leukotriene C4 and D4 in arterial blood of asthmatic patients during remission.

We measured the amounts of leukotriene C4 and D4 in the arterial blood of asthmatic patients during remission and compared these with the amounts of leukotrienes in the arterial blood of asthmatic patients during acute asthma, which had been reported in our previous study. Leukotriene C4 and D4 was detected in five patients during remission at 50.68 +/- 8.28 and 36.68 +/- 17.31 pg/mL (mean +/- SD), respectively. In five control subjects, the amounts of leukotriene C4 and D4 were 78.22 +/- 34.65 and 55.06 +/- 13.54 pg/mL (mean +/- SD), respectively. As cited in our previous report, the amounts of leukotriene C4 and D4 in arterial blood of asthmatic patients during acute asthma were 523.33 +/- 737.06 and 495 +/- 304.48 pg/mL. Hence, there were no significant differences in the leukotriene C4 and D4 values between asthmatic patients during remission and control subjects, whereas there was a significant difference in the leukotriene D4 values between asthmatic patients during acute asthma and, asthmatic patients during remission or control subjects (P less than .01). In addition, the leukotriene C4 values in asthmatic patients during acute asthma were larger than in asthmatic patients during remission or control subjects without a significant difference. The amounts of leukotriene C4 and D4 in arterial blood of asthmatic patients may reflect the degree of severity of acute asthma.

Adult↗
PubMed1990

[Thin-section computed tomography of the normal minor fissure].

The minor fissure was studied with thin computed tomographic (CT) sections (2 mm thickness, 3 mm interval) in 50 patients. It showed high density line or area in all patients. In nine patients CT sections were not obtained through the all region of the minor fissure. Of other 41 patients the fissure was complete in 12 (29%), slightly incomplete in 18 (44%), half incomplete in 7 (17%), and considerably incomplete in 4 (10%). The upper surface of the middle lobe appeared to be upwardly convex in all 50 patients. The location of the highest portion of the minor fissure was hilar in 12 (24%) of 50 patients, medial 1 (2%), anterior 0 (0%), lateral 8 (16%), posterior 3 (6%), dorsal 10 (20%), central 12 (24%), others 2 (4%), and indeterminate 2 (4%). The minor fissure was higher medially than laterally in 22 (44%) patients, and higher posteriorly than anteriorly in 40 (80%) patients. The lowest portion of the minor fissure was anterior in 20 (40%) patients, lateral in 4 (8%), and posterior 3 (6%). The anterior vein of the anterior segment of the right upper lobe (V3b) came in contact with the minor fissure in 20 (40%) patients. In 18 (90%) of these 20 patients minor fissure medial to V3b was incomplete partially. Three dimensional reconstruction image of the minor fissure improved understanding of the anatomy. Familiarity with the anatomic detail of the minor fissure and with variations in the relationships of the upper and middle lobes is useful in localization or extension of a lesion.

Adult↗
PubMed1990

[Problems in the current education and training system for occupational health physicians in Japan and strategies to solve them].

Occupational Health Physician (OHP) has been defined as a title in the Occupational Safety and Health Law since 1972 when the Law was first implemented. The Law stipulates that each manager of an establishment with 50 or more workers is requested to appoint an OHP from among qualified physicians. The small number of applicants to OHP, especially from the younger generation, has continued for more than twenty years causing the average age of OHPs in Japan to rise. The shortage of successors to OHPs in active service is also very serious. A rapid increase in the number of graduates from medical schools is expected in the near future and as a result many untrained physicians in occupational health will flow into this field. It is necessary to establish an educational and training system which is related to an OHP certification system, so that the ability of OHP can be improved and that they will be able to expand their specialty. To reach this final goal, analyses and planning on the following issues of OHP must be done comprehensively; responsibilities, specialty, educational methods and course, necessary number to be trained and its allocation, and cooperation with other specialists in the field. It is also crucial to establish an effective relationship between the occupational health service system and the community health service system. Some suggestions are made to promote these issues.

Adult↗