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Biomedical subjects

S Uda

Publications and source records attributed to S Uda.

At least 19 recordsLinked to original sources
PubMed1998

Mesangial proliferative nephritis in man is associated with increased expression of the cell survival factor, Bcl-2.

Although most studies suggest that the hypercellularity in mesangial proliferative nephritis is due to increased cell proliferation, we hypothesized that it may also be due to increased expression of survival factors that may block their removal (apoptosis). We therefore studied the expression of apoptosis preventing/delaying the bcl-2 gene product in the glomerulus with various human glomerulonephritides. Immunohistochemistry for Bcl-2, proliferating cell associated protein (Ki-67) and alpha-smooth muscle actin (alpha-SMA) was performed on 55 biopsied kidney tissues: 6 cases of orthostatic proteinuria as a control (OP); 6 cases of diffuse proliferative lupus nephritis (WHO type IV, LN-MPGN); 24 cases of IgA nephropathy (IgA); 9 cases of minimal change nephrosis and 10 cases of idiopathic membranous nephropathy. The number of Ki-67-positive cells and the expression of alpha-SMA in the glomerulus were significantly higher in LN-MPGN and IgA. There was a significant positive correlation between glomerular Bcl-2 expression and glomerular cell proliferation evaluated by the number of Ki-67-positive cells (r=0.605, p < 0.01) or glomerular alpha-SMA expression (r=0.674, p < 0.01). Glomerular expression of Bcl-2 in IgA or LN-MPGN was significantly higher than that in OP (p < 0.01 and p < 0.05 vs. OP, respectively). The Bcl-2-positive cells were present in mesangial locations and demonstrated a perinuclear pattern. These results suggest that maintenance of glomerular hypercellularity in human glomerular diseases is partly due to the prevention of mesangial cell death via Bcl-2 expression.

Actins↗
PubMed1997

Cationic Surfactant Adsolubilization of 2-Naphthol and Naphthalene with Titanium Dioxide Having Dodecyl Chain

Adsolubilization of 2-naphthol and naphthalene by cationic surfactant-adsorbed layers formed on titanium dioxides with or without a dodecyl chain was investigated. The cationic surfactants used were dodecyltrimethylammonium bromide and 1,2-bis(dodecyldimethylammonio) ethane dibromide (2RenQ). It was found that the adsolubilized amounts of 2-naphthol and naphthalene increase and reach a maximum and then decrease for both surfactants and titanium dioxides with or without the dodecyl chain, where in the absence of surfactants the incorporated amount of naphthalene on the titanium dioxide with the dodecyl chain is markedly large. The adsolubilized amounts of 2-naphthol and naphthalene were enhanced with the titanium dioxide with the dodecyl chain by adsorption of surfactants, in particular 2RenQ. The admicellar partitioning coefficients also showed that naphthalene is adsolubilized preferentially rather than 2-naphthol and the surface treatment with the dodecyl chain enhances the adsolubilization for two adsolubilizates. Copyright 1997 Academic Press. Copyright 1997Academic Press

Journal Article↗
PubMed1997

Trunk rotation monitor using angular velocity sensors.

To monitor the low back risk imposed by asymmetric postures at workplaces, a method using angular velocity sensors was studied. According to a simple model analysis, trunk rotation could be calculated from the angular velocities measured at both the waist and shoulder and from the inclination of each angular velocity sensor. We thus developed a new detector consisting of an angular velocity sensor (ENC-05D, Murata, Japan) for detecting angular velocity and an acceleration sensor (ADXL05, Analog Devices, USA) for measuring inclination. The precision of the angular velocity sensor was high as the correlation coefficient between the output of the sensor and the true value was 0.9996. When the detectors were affixed to a subject and compared with data measured by a Vicon System 370 (Oxford Metrics, UK), the correlation coefficients between the two methods were 0.949 and 0.815 during model tasks of box transfer and box lifting, respectively. In a model of lifting boxes at different rates, the mean and standard deviation increased according to the task speed. This method was shown to be of practical use for monitoring trunk rotation.

Biomechanical Phenomena↗
PubMed1997

Swell-preventing effect of intermittent exercise on lower leg during standing work.

This study investigated the effectiveness of several possible exercises for performance during standing work in order to prevent lower leg swelling and relieve subjective complaints. Volume changes in the lower leg were measured using bioelectrical impedance plethysmography in 13 healthy male subjects aged 23-36 years. Subjective complaints of leg pain, leg dullness and whole body fatigue were also recorded. Measurements were performed at two-minute intervals during a one-hour period of standing with insertions of one-minute of exercise every 10 min. The exercises were knee-bending, foot-stepping, walking, and heel-raising. The change rates of impedance over one hour were 2.2%, 4.0%, 4.6%, and 6.3%, respectively, indicating that leg volume was increased under all exercise conditions. Among exercises, the swell-preventing effect of knee-bending was strongest, and that of heel-raising was weakest. Heel-raising also yielded the highest number of subjective complaints. Knee-bending, which uses the thigh and calf muscles simultaneously, was considered the most effective for suppressing lower-leg swelling and minimizing subjective complaints.

Adult↗
PubMed1996

[Role of apoptosis in the progression of secondary hyperparathyroidism].

In many tissues, cell proliferation is counterbalanced by apoptosis. Hyperparathyroidism is one of the most important complications in long term dialysis patients and is characterized by remarkable cell proliferation of parathyroid cells. Therefore, alteration in the regulation and clearance of excess cells by apoptosis may occur in hyperparathyroidism. In the present study, we evaluated the expression of Ki-67 (proliferative cell associated protein) and Bcl-2(apoptosis-preventing molecules), and the number of apoptotic cells in the nodular lesion of parathyroid glands with secondary hyperparathyroidism(2 degrees HPT), as compared with primary hyperparathyroidism(1 degree HPT) for clarification of the role of apoptosis in the development of 2 degrees HPT. The number of Ki-67+ cells was remarkably increased in 2 degrees HPT(12.02 +/- 10.87, mean +/- SD) compared to in 1 degree HPT(0.81 +/- 0.53) (p < 0.01). However, the number of apoptotic cells was significantly decreased in 2 degrees HPT(0.10 +/- 0.06) compared to in 1 degree HPT(0.31 +/- 0.19) (p < 0.05). To the contrary, Bcl-2+ cells were increased in 2 degrees HPT(0.35 +/- 0.23) compared to in 1 degree HPT(0.10 +/- 0.13) (p < 0.05). These results suggest that the mechanisms of parathyroid cell proliferation are different in each nodular lesion of 1 degree HPT and 2 degrees HPT. Furthermore, the remarkable proliferation of parathyroid glands may have been due to the reduction of the apoptotic process via Bcl-2 expression in 2 degrees HPT.

Adult↗
PubMed1995

A case of laparoscopic complication: injury of the left common iliac vessels and subsequent acute compartment syndrome of the left leg.

A 45-year-old Japanese woman underwent a laparoscopy-assisted vaginal hysterectomy. Insertion of a trocar injured the left common iliac artery and vein, which were repaired within 2.5 hours. Postoperatively the patient presented an acute compartment syndrome of the left leg. Fasciotomy and rehabilitation rescued her from functional disturbances.

Acute Disease↗
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↗
PubMed1992

Significance of peritoneal macrophages on fertility in mice.

OBJECTIVE: To elucidate the role of peritoneal macrophages in infertility, we investigated how the presence of peritoneal macrophages would affect fecundity in mice. Moreover, we also studied the effects of interleukin-1 on embryonic development. STUDY DESIGN: Mice were administered OK-432 intraperitoneally to induce macrophage infiltration of the peritoneal cavity; ovulation was then induced and animals were mated. On day 13 of gestation, fetuses were counted. After injection of OK-432 or interleukin-1, the mice were mated. Three days later, embryos were collected and the stage of embryo development was determined. RESULTS: In mice given OK-432 (n = 33), four (12%) became pregnant and the mean litter number was 6.0 +/- 3.6, whereas in the control group 23 of 30 mice (77%; p < 0.01) became pregnant and the litter number was 14.1 +/- 5.3 (p < 0.01). OK-432 and interleukin-1 administered intraperitoneally significantly suppressed embryo development (p < 0.01). CONCLUSION: Increased numbers of peritoneal macrophages negatively affect fecundity, probably by suppressing embryonic development.

Animals↗
PubMed1992

High performance liquid chromatography of 99mTc labeled human serum albumin using an N-methylpyridinium polymer column.

Human serum albumin (HSA) labeled with 99mTc (99mTc-HSA) was analyzed by high performance liquid chromatography using a 4-vinylpyridinium polymer column which specifically resolved albumin components such as human mercaptalbumin (HMA), human non-mercaptalbumins (HNA), etc. The 99mTc-HSA radiochromatogram revealed that 99mTc-HSA consisted of several components. The radiochromatographic profile was similar to that of 99mTc-HMA prepared with 99mTc and separated HMA. This suggested that HMA participated mainly in 99mTc-labeling of HSA. When HSA was labeled with a stoichiometric concentration of 99Tc, the HMA peak was significantly decreased and new peaks were revealed by absorbance at 280 nm. From these results, the role of HMA in labeling HSA with 99mTc was elucidated.

Chromatography, High Pressure Liquid↗
PubMed1992

The role of the peritoneal macrophage on the infertility associated with endometriosis.

In investigating the cause of infertility in patients with endometriosis, not only organic disturbances, but also other factors must be considered. I here discuss the participation of interleukin-1 (IL-1) in peritoneal fluid (PF) in infertility and embryonal developmental failure in animal experiment. I next investigated the mechanism for this in mice. The number of corpora lutea and the state of cleavage of the fertilized ovum 96 hours after hCG administration under influence of M phi and IL-1 were investigated. Further in a culture system of human endometrial interstitial cells, the content of intracellular glycogen, which is a source of energy for the growth of the fertilized ovum after implantation, as well as the influence of IL-1 on enzymes metabolizing intracellular glycogen were investigated. As the result, it is considered that M phi in the peritoneal cavity secrete IL-1, which has no influence on ovulation, but inhibits cleavage of the fertilized ovum, decreases the content of intracellular glycogen in the endometrium, and disturbs the environment for ovular growth after implantation, resulting in infertility.

Animals↗
PubMed1991

[The role of the peritoneal macrophage in infertility associated with endometriosis--animal experiment].

In this study, the role of the peritoneal macrophage (M phi) in the infertility of endometriosis patients was investigated through clinical and animal experiments. In addition, the effect of prednisolone as a treatment of infertility caused by endometriosis was evaluated in animal experiments. The number of M phi and the level of IL-1 in the peritoneal fluid were measured. The results showed that the number of M phi and the level of IL-1 increased in 1/3 of patients with endometriosis. Next, the effect of M phi and IL-1 on the pregnancy rate and the number of conceptions was studied in animal experiments. The conception rate and littler number significantly decreased when M phi increased in the animal peritoneal cavity after injection of OK-432. In the experiment with IL-1 injection into the peritoneal cavity, similar results were obtained, and in the group of animal with suppression of M phi function due to prednisolone administration, both of the rate of pregnancy and the number of litters increased remarkably. It can therefore be assumed that the mechanism of infertility in women with endometriosis is associated with peritoneal M phi, or, more specifically, with M phi-produced IL-1.

Animals↗