Biomedical subjects

A Minami

Publications and source records attributed to A Minami.

At least 19 recordsLinked to original sources

PubMed2001

Analysis of transforming activity of human synovial sarcoma-associated chimeric protein SYT-SSX1 bound to chromatin remodeling factor hBRM/hSNF2 alpha.

Human synovial sarcoma has been shown to exclusively harbor the chromosomal translocation t(X;18) that produces the chimeric gene SYT-SSX. However, the role of SYT-SSX in cellular transformation remains unclear. In this study, we have established 3Y1 rat fibroblast cell lines that constitutively express SYT, SSX1, and SYT-SSX1 and found that SYT-SSX1 promoted growth rate in culture, anchorage-independent growth in soft agar, and tumor formation in nude mice. Deletion of the N-terminal 181 amino acids of SYT-SSX1 caused loss of its transforming activity. Furthermore, association of SYT-SSX1 with the chromatin remodeling factor hBRM/hSNF2 alpha, which regulates transcription, was demonstrated in both SYT-SSX1-expressing 3Y1 cells and in the human synovial sarcoma cell line HS-SY-II. The binding region between the two molecules was shown to reside within the N-terminal 181 amino acids stretch (aa 1--181) of SYT-SSX1 and 50 amino acids (aa 156--205) of hBRM/hSNF2 alpha and we found that the overexpression of this binding region of hBRM/hSNF2 alpha significantly suppressed the anchorage-independent growth of SYT-SSX1-expressing 3Y1 cells. To analyze the transcriptional regulation by SYT-SSX1, we established conditional expression system of SYT-SSX1 and examined the gene expression profiles. The down-regulation of potential tumor suppressor DCC was observed among 1,176 genes analyzed by microarray analysis, and semi-quantitative reverse transcription--PCR confirmed this finding. These data clearly demonstrate transforming activity of human oncogene SYT-SSX1 and also involvement of chromatin remodeling factor hBRM/hSNF2 alpha in human cancer.

Agar↗

PubMed2001

Cadmium toxicity in synaptic neurotransmission in the brain.

Chronic exposure to cadmium causes central nervous system disorders, e.g. olfactory dysfunction. To clarify cadmium toxicity in synaptic neurotransmission in the brain, the movement of cadmium in the synapses was examined using in vivo microdialysis. One and 24 h after injection of (109)CdCl(2) into the amygdala of rats, (109)Cd release into the extracellular space was facilitated by stimulation with high K(+), suggesting that cadmium taken up by amygdalar neurons is released into the synaptic clefts in a calcium- and impulse-dependent manner. Moreover, to examine the action of cadmium in the synapses, the amygdala was perfused with artificial cerebrospinal fluid containing 10-30 microM CdCl(2). The release of excitatory neurotransmitters, i.e. glutamate and aspartate, into the extracellular space was decreased during perfusion with cadmium, while the release of inhibitory neurotransmitters, i.e. glycine and gamma-amino butyric acid (GABA), into the extracellular space was increased during the period. These results suggest that cadmium released from the amygdalar neuron terminals affect the degree and balance of excitation-inhibition in synaptic neurotransmission.

Amygdala↗

PubMed2001

Zinc homeostasis in the brain of adult rats fed zinc-deficient diet.

Zinc concentration and (65)Zn uptake in the brain of rats fed zinc-deficient diet for 12 weeks were examined, based on a previous finding of the impairment of learning behavior by the zinc deprivation. Zinc concentrations in the brain, except for the hippocampal formation, did not decrease significantly in zinc-deficient rats, whereas zinc concentration in the liver of the zinc-deficient rats was approximately half that of control rats. When zinc-deficient rats were subjected to brain autoradiography with (65)Zn, (65)Zn concentration in any brain region of zinc-deficient rats was significantly higher than in control rats 6 days after injection of (65)ZnCl(2). The increase rate of (65)Zn concentration in the brain by the zinc deprivation was approximately 150%, and was similar to those in the liver and serum, suggesting that dietary zinc deprivation may cause a scarcity of zinc in the brain, in addition to the peripheral tissues such as the liver. These results indicate that the adult brain is responsive to dietary zinc deprivation. In the brain of zinc-deficient rats, the increase rate of (65)Zn concentration in the hippocampal formation seemed to be low compared to those in other brain regions. The hippocampal formation may be the most responsive to dietary zinc deprivation in the adult brain. The present finding demonstrates that zinc homeostasis in the brain is altered by chronically dietary zinc deprivation.

Animal Feed↗

PubMed2001

Effects of major histocompatibility complex matching on graft survival in allogeneic rat limb transplantation.

Differences in the major histocompatibility complex (MHC) between recipients and donors present a problem because of immunologic responses in graft rejection. The purpose of this study is to clarify the efficacy of MHC matching against acute graft rejection of allogeneic limb transplants in rats. Right hindlimb transplantations were performed using various MHC-mismatched pairs of inbred rats. The rats were classified into 5 groups according to the differences in subregions of the RT1 (rat MHC) between the recipient and the donor: group 1, RT1-A,B,D barrier (the differences of RT1-A,B,D subregions); group 2, RT1-A barrier; group 3, RT1-B,D barrier; group 4, RT1-B barrier; and group 5, RT1-D barrier. The mean survival time significantly decreased in group 1 and increased in group 4. The results suggest that MHC matching clearly improves survival of transplanted limbs. Specifically, both RT1-A and D matching is the most effective compatibility in prolonging survival time of allogeneic limb transplants in rats.

Animals↗

PubMed2000

AMP-Activated protein kinase is activated by the stimulations of G(q)-coupled receptors.

The AMP-activated protein kinase (AMPK) functions as a metabolic sensor that monitors cellular AMP and ATP levels. Platelet-activating factor (PAF) activates endogeneous AMPKalpha1 in Chinese hamster ovary cells expressing the PAF receptor coupled with both G(i) and G(q), but its activity was not inhibited after treatment with islet-activating protein. Norepinephrine and bradykinin also activated AMPKalpha1 in cells expressing the G(q)-coupled alpha(1b)-adrenergic receptor and bradykinin receptor, respectively. Stimulations of the G(i)-coupled alpha(2A)-adrenergic receptor, fMet-Leu-Phe receptor, prostaglandin EP3alpha receptor, and G(s)-coupled beta(2)-adrenergic receptor did not activate AMPKalpha1. AMPKalpha1 thus is activated specifically by stimulation of G(q)-coupled receptors. G(q)-coupled receptors transmit the signal for GLUT4 translocation and glucose uptake through an insulin-independent pathway. However, direct activation of AMPKalpha1 with treatment of 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside did not trigger GLUT4 translocation nor stimulate glucose uptake in our cells. Thus, activation of AMPKalpha1 via G(q) is not sufficient to trigger GLUT4 translocation or stimulate glucose uptake.

AMP-Activated Protein Kinases↗

PubMed2000

Coracoacromial arch decompression in rotator cuff surgery.

In rotator cuff surgery it is important to obtain adequate decompression of the coracoacromial arch. However, it is difficult to localize the impingement site preoperatively. Based on histological and morphological studies and the clinical findings in 45 patients and 15 cadavers, we have tried to determine the impingement site. In addition, as a part of these investigations, we assessed the clinical outcome for 100 patients. Soft tissue decompression was indicated in 12 shoulders, anterior acromioplasty in 67 and anterior acromioplasty with coracoplasty in 21. According to Neer's criteria there were 92 satisfactory and 8 unsatisfactory results. The mean postoperative UCLA score was 33.4 points and the results were rated excellent in 78, good in 18 and fair in 4.

Acromion↗

PubMed2000

Effect of the lipoprotein lipase activator NO-1886 on adriamycin-induced nephrotic syndrome in rats.

Hyperlipidemia associated with nephrotic syndrome may play a role in the deterioration of renal function. Tsutsumi et al have previously reported that the novel compound NO-1886 increases lipoprotein lipase (LPL) activity, resulting in a reduction of plasma triglycerides and an elevation of high-density lipoprotein (HDL) cholesterol in normal rats. The aim of this study was to ascertain whether NO-1886 suppresses the renal injury by treatment of the hyperlipidemia in an Adriamycin (Kyowa Hakko Kogyo, Tokyo, Japan) induced nephrosis rat model fed a high-protein diet that induced renal dysfunction and tubulointerstitial injury. Administration of Adriamycin caused hyperlipidemia, proteinuria, and edema with ascites in rats in 4 weeks. Furthermore, a combination of Adriamycin and a high-protein diet increased plasma creatinine and blood urea nitrogen (BUN) and decreased plasma albumin. Histologically, in Adriamycin-treated rats, marked interstitial cellular infiltration, tubular lumen dilation, and tubular cast formation in the kidney were observed. NO-1886 decreased plasma triglyceride and increased HDL cholesterol in Adriamycin-induced nephrotic rats. NO-1886 treatment reduced plasma creatinine and BUN levels and increased plasma albumin in Adriamycin-treated rats; it also ameliorated the ascites and proteinuria. Histologically, NO-1886-treated rats showed a quantitatively significant preservation of tubulointerstitial lesions. These data suggest that NO-1886 may have a protective effect against Adriamycin-induced nephrosis with tubulointerstitial nephritis in rats by a modification of the plasma lipid disorder.

Animals↗

PubMed2000

Force distribution through the wrist joint in patients with different stages of Kienböck's disease: using computed tomography osteoabsorptiometry.

The pattern of subchondral bone density has been considered to reflect the stress distribution that occurs under physiologic loading conditions. To determine the force distribution through the wrist joint with Kienböck's disease in living subjects, we applied a computed tomography osteoabsorptiometry and investigated the subchondral bone density pattern across the radio-carpal joint of 6 normal subjects and 10 patients suffering from Kienböck's disease (Lichtman's stage IIIA, 5 patients; stage IIIB, 5 patients). A single density maximum was found in each scaphoid and lunate fossa in all normal subjects. Among the subjects with Kienböck's disease, the current analysis demonstrated that the density maximum area significantly increased in the scaphoid fossa and decreased in the lunate fossa from stage IIIA to IIIB group. These findings indicate that the load is shifted away from the lunate to the scaphoid with the progression of Kienböck's disease in living subjects.

Absorptiometry, Photon↗

PubMed2000

Modification of the Sauvé-Kapandji procedure with extensor carpi ulnaris tenodesis.

The Sauvé-Kapandji procedure is a useful treatment option for osteoarthritis of the distal radioulnar joint. Recent reports of a painful unstable proximal ulnar stump prompted us to develop a method of stabilizing the proximal stump of the ulna during the Sauvé-Kapandji procedure by using a half-slip of the extensor carpi ulnaris. Thirteen osteoarthritic wrists (8 primary and 5 traumatic) in 8 men and 5 women with an average age of 50 years were treated by this method. The length of the follow-up periods averaged 36 months. Pain improved in all patients after surgery but pain was elicited over 1 ulnar stump by direct pressure. Both pronation/supination and flexion/extension had statistically significant improvement with the exception of flexion. Grip strength improved in all wrists after surgery. Postoperative x-rays improved alignment in both coronal and lateral planes. Stabilization of the proximal ulnar stump associated with Sauvé-Kapandji procedure is a useful procedure to prevent an unstable ulnar stump in the treatment of osteoarthritis of the distal radioulnar joint.

Adult↗

PubMed2000

Experimental study of vascularized bone grafts: hypertrophy of the grafted bone.

The mechanism underlying hypertrophy of experimentally vascularized bone grafts was studied in 15-week-old rats. The segmental ulna was grafted to the tibial defect with an external fixator. In experiment 1, 24 rats were classified into four groups to evaluate conventional (non-vascularized), cuff (periosteum-encased, non-vascularized), and vascularized bone grafts, and vascularized segmental grafts with fracture. In experiment 2, 12 rats were classified into two groups according to the presence of mechanical loading. This involved vascularized bone grafts with external fixators, and vascularized bone grafts with external fixators removed after bone union. The bone dynamics of the grafts were investigated by several methods, including roentgenographic analysis, histologic studies, and fluorochrome labeling. In experiment 1, a slight bone formation was recognized in the conventional bone graft, while irregular bone formation with creeping substitution was observed in the cuff graft. The vascularized bone graft showed significant hypertrophy; hypertrophy of the vascularized bone with fracture was greater than that without fracture. In experiment 2, markedly circumferential bone formation was observed after removal of the external fixator, while slight new bone formation was observed during the late postoperative period in bone with an external fixator. These results suggest that hypertrophy can be promoted by artificial fracture of the grafted bone, and that mechanical loading is an important factor for remodeling of grafted bone.

Animals↗

PubMed2000

Taurine improves insulin sensitivity in the Otsuka Long-Evans Tokushima Fatty rat, a model of spontaneous type 2 diabetes.

BACKGROUND: Taurine, a potent antioxidant, has been reported to improve streptozotocin-induced diabetes mellitus, in which the development of diabetes results from an attack by oxygen free radicals on pancreatic beta cells. However, taurine also increases the excretion of cholesterol via conversion to bile acid and would be expected to improve insulin resistance. OBJECTIVE: The effects of taurine on insulin sensitivity were examined in a model rat of insulin resistance and type 2 diabetes-the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. DESIGN: Male OLETF rats were divided into 2 groups at the age of 16 wk: a taurine-supplemented group and an unsupplemented group. As a nondiabetic control, Long-Evans-Tokushima-Otsuka rats were used. An oral-glucose-tolerance test and hyperinsulinemic euglycemic clamp were performed at the ages of 23 and 25 wk. RESULTS: The OLETF rats had hyperglycemia and insulin resistance and they had a greater accumulation of abdominal fat than did control rats. Abdominal fat accumulation, hyperglycemia, and insulin resistance were significantly lower in the taurine-supplemented group than in the unsupplemented group. Serum and liver concentrations of triacylglycerol and cholesterol were significantly higher in the OLETF rats than in the control rats and were significantly lower in the taurine-supplemented group than in the unsupplemented group, presumably because of the increased secretion of cholesterol into bile acid. Taurine-supplemented rats also showed higher nitric oxide secretion, evidenced by increased urinary excretion of nitrite. CONCLUSION: Taurine effectively improves metabolism in OLETF rats by decreasing serum cholesterol and triacylglycerol, presumably via increased secretion of cholesterol into bile acid and decreased production of cholesterol because of increased nitric oxide production.

Adipose Tissue↗

PubMed2000

Survey on antibody against parapoxvirus among cattle in Japan.

A seroepidemiological survey was performed on antibody against parapoxvirus among cattle in Japan using the agar gel immunodiffusion test and enzyme-linked immunosorbent assay. A total 1,819 sera were collected from cattle in various parts of Japan for the survey. The positive rates were in the range of 40 to 98%, and the reactors increased gradually in number with advancing age. These results indicate that parapoxvirus infection is already prevalent among cattle in Japan. It remains to be elucidated, however, whether the antibodies detected have been produced by infection of the same virus or other viruses that belong to the genus parapoxvirus.

Animals↗

PubMed2000

Vascularised fibular grafts. An experience of 102 patients.

The results and complications of 104 vascularised fibular grafts in 102 patients are presented. Bony union was ultimately achieved in 97 patients, with primary union in 84 (84%). The mean time to union was 15.5 weeks (8 to 40). In 13 patients, primary union was achieved at one end of the fibula and secondary union at the other end. In these patients, the mean time to union was 31.1 weeks (24 to 40). Five patients failed to achieve union, with a resultant pseudarthrosis (3 patients) or amputation (2 patients). There were various complications. Immediate thrombosis occurred in 14 cases. In two of 23 patients with osteomyelitis, infection recurred at two and six months after surgery, respectively. Both patients had active osteomyelitis less than one month before the operation. Bony infection occurred in a patient with a synovial sarcoma of the forearm one year after surgery. In 15 patients, 19 fractures of the fibular graft occurred after bony union, all except one within one year after union. In patients in whom an external fixator had been used, fracture occurred soon after its removal. Union was difficult to achieve in cases of congenital pseudarthrosis of the tibia. Appropriate alignment of the fibular graft is an important factor in preventing stress fracture. The vascularised fibula should be protected during the first year after union. Postoperative complications at the donor site included transient palsy of the superficial peroneal nerve in three patients, contracture of flexor hallucis longus in two and valgus deformity of the ankle in three. Vascularised fibular grafts are useful in the reconstruction of massive bony defects. We believe that meticulous preoperative planning, including choosing which vessels to select in the recipient and the type of fixation devices to use, and care in the introduction of the vascularised fibula, can improve the results and prevent complications.

Adolescent↗

PubMed1999

Identification of macrophage migration inhibitory factor (MIF) in rat peripheral nerves: its possible involvement in nerve regeneration.

Macrophage migration inhibitory factor (MIF) is known as a pluripotent immunoregulatory cytokine involved in T-cell activation and inflammatory responses; however, no study on this protein in the peripheral nervous systems has been carried out. We here demonstrated for the first time expression of MIF mRNA and MIF protein in rat sciatic nerves by reverse transcription-polymerase chain reaction, Western blotting, and immunohistochemistry. Immunohistochemical analysis revealed positive staining of MIF, which was largely observed in Schwann cells. Furthermore, we examined MIF mRNA expression in the sciatic nerves by Northern blot analysis in the case of nerve transection. In both proximal and distal segments, the level of MIF mRNA started to increase 12 h after the nerve transection. The level remained high from 24 h up to day 7 after the injury. During the period from days 14 to 21, MIF mRNA sharply decreased to the pre-transection level. In immunohistochemistry, positive staining of MIF was largely observed in axons as well as non-neuronal cells in proximal segments at day 4 after transection. In the distal segments, contrastingly, endoneurial fibroblasts or Schwann cells migrating into neuronal fibers showed positive staining with Wallerian degeneration. Although the precise functions of MIF in the peripheral nerves remain to be elucidated, the present results could represent a major departure from the current state of knowledge, revealing a novel function in the degenerative-regenerative process.

Animals↗

PubMed1999

Two cases of inflammatory bowel disease with multiple myeloma.

A significant increase has been reported in reticuloendothelial neoplasms in patients with inflammatory bowel diseases. We present two rare cases of multiple myeloma in patients with inflammatory bowel diseases. One was in a 58-year-old woman with ulcerative colitis, and the other was in a 59-year old woman with Crohn's disease. In both patients, multiple myeloma occurred during long-term observation of inflammatory bowel disease and during the inactive stage of intestinal inflammation. The multiple myeloma appeared to have resulted from monoclonal gammopathy of undertermined significance in both patients, and was diagnosed by characteristic serum and bone marrow findings. Our findings suggested that multiple myeloma should be particularly considered in women of middle or advanced age with ulcerative colitis or Crohn's colitis and serum monoclonal gammopathy.

Female↗

PubMed1999

Surgical repair of acute collateral ligament injuries in digits with the Mitek bone suture anchor.

Eighteen acute grade III collateral ligament injuries were treated by using the Mitek bone suture anchor. Seven were thumb metacarpophalangeal joint injuries, and eleven were finger proximal interphalangeal joint injuries. Seventeen patients were followed more than 12 months after surgery. All patients were able to use the digits in daily living activities within 5 weeks after surgery, and return to their original work or sports activities within 12 weeks. Pain was completely relieved in 15 patients. Loss of joint motion averaged 7 degrees. In all joints the postoperative lateral stress angle was within 10 degrees of that of the contralateral digit.

Adolescent↗

PubMed1999

The effects of wrist distraction on carpal kinematics.

Changes in carpal kinematics under wrist distraction were studied in fresh cadaveric specimens. A magnetic tracking device measured kinematic motions of the scaphoid, lunate, and third metacarpal relative to the fixed radius in 3 planes of passive motion (coronal, sagittal, and "dart throwers") under progressive distraction loads. The change in percent contribution of the radiocarpal and midcarpal joints was calculated. Radiocarpal motion during extension was decreased as increasing traction was applied, but it increased with flexion. Motion of the scaphoid relative to the lunate was smaller in the oblique plane, resulting in less radiocarpal motion than in the sagittal plane. In the coronal plane, traction had little effect on radial deviation, but ulnar angulation of the scaphoid was greater with ulnar deviation of the wrist. These results suggest that different degrees of tension exist in the palmar and dorsal ligaments with the wrist under traction and during different planes of wrist motion. If wrist motion is desired during fixed traction, such as used clinically with external fixation, the dart-throwers motion (wrist extension with radial deviation and wrist flexion with ulnar deviation) appears to have the least impact on radiocarpal motion. If greater radiocarpal motion is desired, however, such as during postoperative mobilization, flexion-extension and radioulnar deviation will create more radiocarpal motion than the dart-thrower's motion.

Biomechanical Phenomena↗

PubMed1999

Cilostazol, a phosphodiesterase inhibitor, improves insulin sensitivity in the Otsuka Long-Evans Tokushima Fatty Rat, a model of spontaneous NIDDM.

AIM: Angiotensin converting enzyme inhibitors and alpha1-adrenergic blockers improve insulin sensitivity, the mechanism of which was considered, at least in part, to be due to the increased blood flow to muscle. The present study aimed to clarify whether cilostazol, a phosphodiesterase inhibitor, improves insulin sensitivity in a model of spontaneous non-insulin dependent diabetes mellitus (NIDDM), Otsuka Long-Evans Tokushima Fatty (OLETF) rat. METHODS: OLETF rats were divided into the two groups at the age of 16 weeks: the cilostazol-supplemented group (cilostazol 40 mg/kg/day) and the normal-diet group. As a non-diabetic control, we used Long-Evans-Tokushima-Otsuka rats (non-diabetic rats). Oral glucose tolerance test and hyperinsulinemic euglycemic clamp was performed at the ages of 23 and 25 weeks, respectively. Serum levels of lipids and leptin were measured. RESULTS: Body weight and abdominal fat was increased in OLETF rats but cilostazol supplementation did not alter them. Insulin sensitivity, as measured by the hyperinsulinemic euglycemic clamp technique, was significantly decreased in OLETF rats (glucose infusion rate: 73.5 +/- 10.0 vs. 41.5 +/- 9.8 micromol/min/kg body weight, p < 0.01). Cilostazol supplementation improved insulin sensitivity partially but significantly 51.0 +/- 5.7 micromol/min/kg body weight, p < 0.05) in OLETF rats at 25 weeks of age, although it did not decrease serum levels of glucose, lipids or leptin. However, this effect was not observed in non-diabetic rats. CONCLUSION: Cilostazol, which is used in diabetic patients for the treatment of obstructive disease of artery, is expected to have a beneficial effect on insulin sensitivity in NIDDM.

Abdomen↗