Biomedical subjects

S Tsuru

Publications and source records attributed to S Tsuru.

At least 19 recordsLinked to original sources

PubMed1995

Bioelectrical impedance measuring method for standing load evaluation.

A bioelectrical impedance method was used to evaluate the workload in standing jobs. This method is designed to indirectly evaluate swelling of the lower leg by measuring the change in the rate of impedance of the lower leg. In this paper, we studied the relationship between the methods used for swelling evaluation, and studied the measuring conditions of the impedance method by using bioelectrical models. Furthermore, impedance in ten male subjects in three types of standing conditions was measured to check the validity of the model analysis. The results are as follows: 1) The result of theoretical analysis showed that the change in impedance caused by leg swelling is equal to the value obtained by the leg volume measuring method, and twice as great as the value obtained by the leg circumference measuring method. The rate of change in impedance at low frequency is about 4 times greater than that at high frequency. The low frequency impedance measuring method is therefore much more sensitive than the other methods. 2) The results of experimental studies showed that the impedance in the lower legs was reduced as the function of time when quietly standing for 30 mins. The change in the rate of impedance was 6.86 +/- 4.54% (mean +/- SD). This rate is 3-5 times greater than the data reported by other researchers who used volume measurement or impedance measurement at high frequency. This difference fits the results of model analysis, and proved the validity of model analysis and the usefulness of the impedance method as an index of the standing load.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Improvement of macrophage dysfunction by administration of anti-transforming growth factor-beta antibody in EL4-bearing hosts.

An experimental therapy for improvement of macrophage dysfunction caused by transforming growth factor-beta (TGF-beta) was tried in EL4 tumor-bearing mice. TGF-beta was detected in cell-free ascitic fluid from EL4-bearers, but not in that from normal mice, by western blot analysis. The ascites also showed growth-suppressive activity against Mv1Lu cells, and the suppressive activity was potentiated by transient acidification. To investigate whether the functions of peritoneal macrophages were suppressed in EL4-bearers, the abilities to produce nitric oxide and tumor necrosis factor-alpha (TNF-alpha) upon lipopolysaccharide (LPS) stimulation were measured. Both abilities of macrophages in EL4-bearing mice were suppressed remarkably on day 9, and decreased further by day 14, compared with non-tumor-bearing controls. TGF-beta activity was abrogated by administration of anti-TGF-beta antibody to EL4-bearing mice. While a large amount of TGF-beta was detected in ascitic fluid from control EL4-bearers, little TGF-beta was detectable in ascites from EL4-bearers given anti-TGF-beta antibody. Furthermore, while control macrophages exhibited little or no production of nitric oxide and TNF-alpha on LPS stimulation in vitro, macrophages from EL4-bearers administered with anti-TGF-beta antibody showed the same ability as normal macrophages. These results clearly indicate that TGF-beta contributes to macrophage dysfunction and that the administration of specific antibody for TGF-beta reverses macrophage dysfunction in EL4-bearing hosts.

Animals↗

PubMed1994

A simple apparatus using inclinometer for monitoring working postures.

A new apparatus was developed for evaluating a load on the low back caused by working postures by measuring upper body inclination. This apparatus consists of an inclinometer and a portable unit. The inclinometer that uses a magnetic resistance sensor is attached to the upper body of the subject. The portable unit, controlled by a one-chip CPU, is enclosed in a cloth case and carried by the subject on his waist belt. The inclination is measured at a certain interval and recorded in the memory of the portable unit. All the recorded data are later transferred to a host computer and then analyzed. According to the theoretical analysis by using a simple mathematical model, upper body inclination changes according to the height of work places, and one cm difference in height causes more than one degree of upper body inclination. A model work of material handling was carried out to collect sample data. Two male subjects lifted ten boxes onto a platform from a stand in several heights. Both stooped and squat lifting methods were used as the lifting protocol. The mean and standard deviation (SD) of the upper body inclination during work decreased according to the lift distance only in stooped lifting. As a practical application, working postures during the task of changing diapers for handicapped people were analyzed with out apparatus. A female subject changed diapers eight times at different height of beds. The mean value of inclination decreased according to the height of the beds.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Granulocyte colony-stimulating factor enhances the extracellular emission of reactive oxygen from neutrophils stimulated with formylmethionylleucylphenylalanine.

Pretreatment of neutrophils with granulocyte colony-stimulating factor (G-CSF) enhanced luminol-dependent chemiluminescence emission by the stimulation of formylmethionylleucylphenylalanine (FMLP), opsonized zymosan, and zymosan. The intensity of the priming effects was in the following order: FMLP > zymosan > opsonized zymosan. However, the priming effect of G-CSF was not detected by the stimulation of phorbol myristate acetate. The reaction curve with the stimulation of FMLP showed a bimodal shape, and the elevation of the first peak by the priming effect was further prominent in comparison with the elevation of the second peak. This indicates that G-CSF mainly enhances the extracellular release of oxygen radicals in response to the stimulation with FMLP. This is the first report investigating intra- and extracellular events in chemiluminescence reaction of neutrophils primed with G-CSF.

Cytochalasin B↗

PubMed1993

Evaluation of tumor markers in patients with squamous cell carcinoma in the oral cavity.

Serum levels of six tumor markers (carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCCA), immunosuppressive acidic protein (IAP), alpha-fetoprotein (AFP), ferritin (FER), and carbohydrate antigen 19-9 (CA 19-9)) were simultaneously measured in 29 patients with primary squamous cell carcinoma (SCC) of the oral cavity to determine their significance. The positive rates were 34.5% for CEA, 41.4% for SCCA, 51.7% for IAP, 0% for AFP, 10.3% for FER, and 6.9% for CA 19-9 in patients with oral SCC. Therefore, CEA, SCCA, and IAP levels, of which the positive rates were significantly different (P < 0.01) from those of control patients without oral cancer, were considered to be of diagnostic value. The sensitivity (69.0%) and accuracy (90.3%) of the combination assay with these three tumor markers proved to be higher than those obtained with individual markers. A combination assay with CEA, SCCA, and IAP could be useful for the screening of patients with oral cancer.

Adult↗

PubMed1993

Therapeutic effect of granulocyte colony-stimulating factor and cephem antibiotics against experimental infections in neutropenic mice induced by cyclophosphamide.

Effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) against severe infections in cyclophosphamide (CY)-induced neutropenic mice were investigated by its single use or by its combination with cephem antibiotics. Treatment with rhG-CSF increased the number of peripheral blood leucocytes and strikingly shortened the duration of the neutropenic state. Most of the regained population in the peripheral blood leucocytes were neutrophils. Functions of neutrophils, such as phagocytic activity, superoxide release, and expression of Mac-1 molecules, were remarkably enhanced by administration of rhG-CSF. When rhG-CSF was administered to CY-induced neutropenic mice before infection, protective effects against various kinds of bacteria were remarkable. On the other hand, such remarkable effects were not observed when rhG-CSF was administered after infections. However, even in the case of post-infectious treatment, a combination therapy of rhG-CSF with cephem antibiotics, particularly with Cefodizime (CDZM), showed a significant improvement in the survival rate and a decrease in the number of viable bacteria in the liver. These results suggest that a combination therapy of rhG-CSF with cephem antibiotics, especially with CDZM, is an efficient regime against severe infections in patients with neutropenia induced by a heavy anti-tumour chemotherapy.

Animals↗

PubMed1993

Therapeutic effect of granulocyte colony-stimulating factor (G-CSF) on the protection against Listeria infection in SCID mice.

Anti-listerial activity in SCID mice as well as in control C.B-17 mice was augmented by granulocyte colony-stimulating factor (G-CSF). After 1 x 10(3) colony-forming units of Listeria monocytogenes (strain EGD) were intravenously inoculated, mice were intraperitoneally injected with G-CSF at a daily dose of 500 micrograms/kg for 5 days. The numbers of viable bacteria in the liver were significantly lower in G-CSF-treated SCID and C.B-17 mice than in non-treated mice. The surface marker analyses on gamma delta T-cell receptor (TcR), Mac-1 and F4/80, and dichlorofluorescein oxidative activity, showed a possible contribution of activated neutrophils, but not gamma/delta T cells nor activated macrophages, to the augmentation of anti-listerial activity in SCID mice. This study is one of the first reports on the anti-microbial effect of G-CSF in therapeutic use.

Animals↗

PubMed1992

Increased mitochondrial uptake of rhodamine 123 by CDDP treatment.

Rhodamine 123 (R 123) is a positively charged dye at physiological pH that accumulates specifically in the mitochondria of living cells without cytotoxic effect. In the present study, the uptake of R 123 by EL-4 lymphoma cells in culture with anticancer agents was measured by flow cytometry. Changes in R 123 uptake during the cultivation period were compared with cell distribution at different phases of the cell cycle. According to the increase in the proportion of S phase cells, mitochondrial synthesis increased, giving rise to a maximal fluorescence intensity of about 1.3-fold. Synchronous cultures showed the same relationship between increased mitochondrial uptake of R 123 and the S phase fraction as was observed in normal cultures. After treatment with 10(-3) M 5-fluorouracil (5-FU) for 1 h, EL-4 cells showed an increased binding of R 123 per cell followed by an accumulation of early S phase cells transiently. However, uptake of R 123 decreased 24 h later. On the contrary, after treatment with 10 micrograms/ml of cis-diamminedichloroplatinum (CDDP), a G2 + M block was observed from 12 h of reseeding and accumulation of the G2 + M cells continued. In this case, high uptake of R 123 continued during the observation period. From these results, mitochondrial synthesis seemed to increase according to the increment in proportion of S phase when the acceleration of the cell cycle turnover was augmented or the cycle was blocked in S phase by 5-FU. CDDP inhibited the cell division at G2 + M phase and caused increased R 123 fluorescence per cell. The stainability of R 123 may indicate the activity of cell division and may be a good way of evaluating the efficacy of antitumor drugs on the cells.

Cell Cycle↗

PubMed1992

Enhancement of host defense by Y-25510, (+-)-3-[4-(2-dimethylamino-1-methylethoxy)phenyl]-1H-pyrazolo[3,4 -b] pyridine-1-acetic acid, a novel synthetic compound. A comparison with recombinant human granulocyte colony-stimulating factor in 5-fluorouracil-treated mice.

The effect of a novel synthetic compound, Y-25510, (+-)-3-[4-(2-dimethylamino-1-methylethoxy)phenyl]-1H-pyrazolo[3,4 -b] pyridine-1-acetic acid, on recovery from long-lasting leukopenia induced by 5-fluorouracil was compared with that of recombinant human granulocyte colony-stimulating factor (rhG-CSF). When mice were administered i.p. with 5-FU (200 mg/kg) on days 0 and 7, intravenous administration of Y-25510 (100 and 1000 micrograms/kg) prevented the decrease in the peripheral leukocyte and neutrophil number and accelerated the recovery from leukopenia. Subcutaneous administration of rhG-CSF (50 micrograms/kg) did not prevent leukopenia but accelerated the recovery from leukopenia. In particular, peripheral neutrophil number increased over a normal level. The administration of Y-25510 (10, 100 and 1000 micrograms/kg) restored the decrease in the number of bone marrow cells, spleen cells, lymphocytes, neutrophils and monocytes. The administration of rhG-CSF (50 micrograms/kg) restored the decrease in the number of bone marrow cells, spleen cells, and neutrophils but not that of lymphocytes and monocytes. In fractions of bone marrow cells on day 21, the administration of Y-25510 (1000 micrograms/kg) showed a tendency of restoring the decrease in neutrophil number. In conclusion, the administration of Y-25510 prevented leukopenia and accelerated the recovery from leukopenia in the 5-FU-treated mice. It is suggested that the mechanism of the restorative action of Y-25510 is different from that of rhG-CSF. In a number of immature bone marrow cells Y-25510 has a potent stimulatory effect on the recovery from the decrease in number of hematopoietic cells, keeping a balance in number of each blood cell.

Adjuvants, Immunologic↗

PubMed1992

AIDS-like disproportion of minor T-cell subsets in Japanese patients with Wegener's granulomatosis.

Fifteen Japanese patients with Wegener's granulomatosis (WG) were evaluated according to their lymphocyte subset abnormalities. Two colour immunofluorescent flow cytometry was used to distinguish the lymphocyte subset alterations. WG group showed a decrease in the percentage of CD4+ cells and the increase of CD8+ cells. Within the NK cell family, the functionally unidentified CD8+57+ cells were markedly elevated. The disproportion of the lymphocyte subsets (CD4+ decreases CD8+57+ increases) were similar to those of Acquired Immunodeficiency Syndrome (AIDS) and AIDS relating complexes (ARC). To assess silent infection of Human immunodeficiency virus (HIV), the polymerase chain reaction (PCR) was done for all patients to selectively amplify specific HIV proviral DNA sequences in peripheral blood mononuclear cells, HIV-1 proviral DNA was not found in any patients but these changes of WG might suggest a possible adaptive response to unknown viral infection.

AIDS-Related Complex↗

PubMed1992

Is injectable collagen truly safe?

Most patients have no response to injectable collagen or silicone, but some cases may have positive or 'undersea' (= clinically negative but immunologically positive) response to collagen. From the results of the Macrophage migration inhibition test, the relative immunogenicity was augmented most when we used implants with the following combination. The first immunization was collagen and the second one was collagen with silicone. The augmented antigenicity might be enough to cause an allergic reaction to the patients who had no response to each implant alone.

Adjuvants, Immunologic↗

PubMed1992

Intracellular hydrogen peroxide production by peripheral phagocytes from diabetic patients. Dissociation between polymorphonuclear leucocytes and monocytes.

Although the standard assays for reactive oxygen species have been based on the measurement of those released into the extracellular environment, the microbicidal capacity to the engulfed microorganisms is mainly dependent on those released into the intracellular environment, such as phagosomes. We studied intracellular oxidative activities of individual phagocytes by dichlorofluorescein (DCFH) oxidation assay to investigate the relationship between the reactive oxygen species released intracellularly and the impaired microbicidal capacity in diabetic patients. Time courses of intracellular production of hydrogen peroxide by polymorphonuclear leucocytes (PMNL) and monocytes were observed at the resting condition and after the stimulation with phorbol myristate acetate (PMA; 160 nM) by flow cytometry. Thirty-four patients with non-insulin-dependent diabetes mellitus (NIDDM) and 23 age-matched healthy volunteers were subjected to the studies. PMNL from patients with NIDDM showed a significantly decreased capacity to produce hydrogen peroxide after the stimulation (P less than 0.05 at 15 min, P less than 0.01 at 30 and 45 min). By contrast, intracellular hydrogen peroxide production by monocytes at the resting condition and an early stimulatory phase (8 min after the stimulation) was significantly (P less than 0.01) enhanced in patients with NIDDM compared with that in controls. Both the changes of intracellular hydrogen peroxide production observed in PMNL and monocytes from patients with NIDDM were in association with an increased haemoglobin Alc level in erythrocytes, but did not relate to total cholesterol and triglyceride levels in the serum. The possible mechanisms of these dissociated changes in hydrogen peroxide producing capacity of phagocytes from patients with NIDDM are discussed.

Adult↗

PubMed1992

Reduced CD4-CD8 T cell ratios in patients with Wegener's granulomatosis.

All of the patients with Wegener's granulomatosis (WG), whom we studied, exhibited abnormalities in lymphocyte subsets. We used two-color immunofluorescence flow cytometry to examine the lymphocyte subset alterations. WG group showed a decrease in the percentage of CD4+ cells and an increase of CD8+ cells. Within the NK cell family, functionally unidentified CD8+57+ cells were markedly increased in number. The disproportion of these lymphocyte subsets (CD4+ decreases, CD8+57+ increases) was similar to that seen in Acquired Immunodeficiency Syndrome (AIDS) and AIDS related complex (ARC).

Adult↗

PubMed1992

[Structure of communication between physicians and patients from the viewpoint of community health].

Understanding the structure and problems of communication between physicians and patients should be achieved before introducing a medical information network system for community health. To this end a questionnaire survey was performed on 2,362 patients who saw physicians in medical facilities in a certain district of Hiroshima city. As a result, it was revealed that 'explanations given by doctors' and 'explanatory ability of patients' were mutually closely related and formed a basis for other aspects of communication and patient behavior. Satisfaction with the explanation given by physicians declined with examination time of less than 5 minutes and examination in hospitals rather than in clinics. Explanatory ability of patients decreased as age of patients increased and showed a remarkable decrease in patients of more than 80 years old. This suggested the existence of risk that information necessary for safe examinations may not be transmitted to physicians. These results pointed out the importance of a supporting system of communication especially for the elderly patient.

Communication↗

PubMed1992

Depression of early protection against influenza virus infection by cyclophosphamide and its restoration by protein-bound polysaccharide.

Relationship between depression of early protection against influenza virus infection and the decrease in the number of peripheral polymorphonuclear leukocytes in cyclophosphamide-treated mice was investigated using protein-bound polysaccharide (PSK), which had been shown to exert a potent restorative effect on leukocytopenia in immunocompromised hosts. Following intranasal inoculation with influenza virus (1.5 x 10(3) PFU) into untreated mice, the pulmonary virus titer progressively increased during 3 days and decreased gradually from the day 7 after infection. The treatment of mice with cyclophosphamide (150 mg/kg) 2 days before infection markedly enhanced the pulmonary virus multiplication from the early phase of infection, and the higher virus titer was maintained thereafter. When mice were given cyclophosphamide after PSK-treatment, virus titers from the early to late phases of infection were lower than those in untreated mice.

Adjuvants, Immunologic↗

PubMed1992

[Production of reactive oxygen species by rat alveolar macrophages. Dissociation between the intracellular and extracellular release of hydrogen peroxide].

In order to clarify the features of reactive oxygen species produced by rat alveolar macrophages (AMs), the concentrations of intracellular and extracellular hydrogen peroxide were measured under various experimental conditions. Intracellular hydrogen peroxide was measured by DCFH method using a flow cytometer, while the extracellularly released fraction was measured by scopoletin method using a spectrophotometer. The concentration of intracellular hydrogen peroxide after stimulation with opsonized zymosan (10 micrograms/ml) was significantly higher than that after stimulation with phorbol myristate acetate (PMA; 100 ng/ml). On the other hand, hydrogen peroxide released extracellularly after stimulation with PMA was significantly greater that that after stimulation with opsonized zymosan. These results indicate that the soluble membrane stimulant and the phagocytic particles have different mechanisms in activating the production of hydrogen peroxide in AMs. That is, hydrogen peroxide induced by PMA was mainly released extracellularly, while that induced by zymosan was mainly released into the intracellular environment. At rest, the concentration of intracellular hydrogen peroxide in rat AMs was high. Potassium cyanate, a known mitochondrial inhibitor, suppressed the intracellular hydrogen peroxide in AMs not only at rest but also after stimulations, indicating that most of the reactive oxygen species released into the intracellular environment in AM are produced by mitochondria. From these results, in order to gain a closer insight into the function of AMs, it is very important to distinguish the oxidative metabolites produced intracellularly which are related to bactericidal function from those of the extracellularly released fraction which give rise to lung damage.

Animals↗

PubMed1991

Effects of macrophage colony-stimulating factor on reduction of viable bacteria and survival of mice during Listeria monocytogenes infection: characteristics of monocyte subpopulations.

Mice could well tolerate infection with a lethal dose of Listeria monocytogenes after intraperitoneal preinjections with 250 micrograms of macrophage colony-stimulating factor (M-CSF) per kg of body weight for 5 days. The characteristic changes in the surface markers (Mac-1, LFA-1, and F4/80) of peripheral monocytes were also investigated in order to analyze the mechanism of protection by M-CSF. This investigation shows the excellent effect of intraperitoneal preinjections of M-CSF on the reduction of viable Listeria organisms and the improvement of survival after an intravenous Listeria infection.

Animals↗

PubMed1991

Enhanced resistance against Listeria monocytogenes achieved by pretreatment with granulocyte colony-stimulating factor.

Phagocytosis, H2O2 production, Mac-1 expression, and in vivo elimination of Listeria monocytogenes were enhanced in granulocyte colony-stimulating factor (G-CSF)-treated mice. Transfer of polymorphonuclear leukocytes prolonged survival of mice infected with a lethal dose of L. monocytogenes. G-CSF augments the functions of polymorphonuclear leukocytes and thus plays a role in protection.

Animals↗