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N Matsui

Publications and source records attributed to N Matsui.

At least 91 records · Page 5Linked to original sources
PubMed1998

Establishment of a non-union model using muscle interposition without osteotomy in rats.

Many attempts have described a standard experimental model for fracture non-union in laboratory conditions, but the majority of them produced after an experimental osteotomy, so it is different from clinical disturbed fracture healing. The purpose of this study is to establish a standard method for producing fracture non-union with only muscle interposed into the fracture site in rats. Bilateral tibial fractures were made in forty-eight male Wister rats by three point bending and we surgically interposed the distal end of the tibialis anterior muscle into the fracture site. They were sacrificed at 1, 2, 3, 6, 12, 24, 48, and 96 weeks after fracture. The rentgenograms were obtained, and the fractured tibias were harvested in each time period and investigated histologically and immunohistochemically. The rentgenogram at six weeks, in the non-union rats, showed abundant callus at each end of the fracture fragments, but no bridging callus. The histological finding with hematoxylin and eosin, at this point, shows no bridging soft callus, and small isolated regions of cartilage were observed only where the bone was not covered by the muscle. The proliferating cell nuclear antibody immunostaining which is associated with cell proliferation was abruptly lost in chondrocytes at two weeks. This early disappearance of chondrocytes without endochondral ossification may be a significant etiological factor in the development of a non-union. This non-union model is technically simple and reproducible, and dose not require periosteal stripping or surgical osteotomy to produce an artificial bone gap.

Animals↗
PubMed1998

MaMi, a human endometrial stromal sarcoma cell line that constitutively produces interleukin-6, interleukin-8, and monocyte chemoattractant protein-1.

BACKGROUND: Uterine endometrial stromal sarcoma is a rare neoplasm with a morphology that closely resembles that of the proliferative endometrial stroma. To understand its pathologic characteristics, we established a novel cell line, MaMi, from a primary culture of an endometrial stromal sarcoma obtained from a 65-year-old Japanese woman. METHODS: We observed the morphology of MaMi cells and performed immunohistochemical analysis on the primary tumor and transplants in nude mice. Prolactin, insulin-like growth factor-binding protein-1, interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1, intercellular adhesion molecule-1, E-selectin, vascular cell adhesion molecule-1, and fibronectin production in the culture medium of MaMi cells were also examined. RESULTS: MaMi cells were shown to exhibit a fibroblast-like morphology in vitro, and they adopted a more elongated appearance in response to 12-O-tetradecanoyl phorbol-13-acetate (TPA). On injection into nude mice, the cells gave rise to subcutaneous tumors. Immunohistologically, both the primary tumor and MaMi cell-induced tumors stained positively with antibodies to neuron-specific enolase or vimentin. MaMi cells constitutively produced IL-6, IL-8, and monocyte chemoattractant protein-1 in vitro. Interleukin-1beta, (100 pmol/L), tumor necrosis factor-alpha (1 nmol/L), and lipopolysaccharide (1 microg/mL) each increased the release of IL-6, IL-8, and monocyte chemoattractant protein-1 by MaMi cells. TPA (10 nmol/L) also stimulated the production of IL-6 and IL-8 by these cells, but inhibited that of monocyte chemoattractant protein-1. CONCLUSIONS: We demonstrated that MaMi cells closely resemble proliferative endometrial stromal cells not only morphologically, but also functionally. This cell line may prove valuable in understanding the role of cytokines produced by tumor cells in the pathogenesis of endometrial stromal sarcoma and may also be useful as an in vitro model of functioning endometrial stromal cells.

Aged↗
PubMed1997

Reduction of hyponatremia in a schizophrenic with polydipsia-hyponatremia syndrome by surgical intervention.

In a chronic schizophrenic with polydipsia-hyponatremia syndrome, we observed physiological data consecutively before and after a successful LAPIDES vesicostomy for his bladder retention. Although his polydipsia was unchanged, frequency of hyponatremia was significantly reduced after the operation. We found that bladder retention might be one of the factors relevant to the prediction of hyponatremia from diurnal weight gain.

Adult↗
PubMed1997

Effect of acid-base disturbances on aldosterone secretion in man.

The present study was carried out to elucidate whether changes in blood pH induced by administration of alkalinizing and acidifying agents influence aldosterone secretion in man. Since aldosterone secretion is known to be regulated by various factors such as the renin-angiotensin system, adrenocorticotropic hormone (ACTH), and serum potassium concentration, these indices were simultaneously measured during manipulation. Oral administration of tris hydroxymethyl aminomethane (THAM) resulted in a moderate but not significant decrease in serum aldosterone together with an increase in blood pH, whereas plasma renin activity (PRA) remained unchanged and serum potassium was elevated. ACTH and cortisol decreased significantly. Following CaCO3 ingestion, blood pH, serum potassium concentration, and hormones did not change significantly compared with before ingestion. NH4Cl ingestion showed a significant fall of blood pH and serum cortisol, on the other hand, aldosterone increased significantly compared with CaCO3 ingestion. Following NaHCO3 ingestion, serum aldosterone decreased with an increase in blood pH compared with before ingestion, while serum cortisol and PRA did not change significantly. The overall results of experiments using THAM, CaCO3, NaHCO3, and NH4Cl led to the conclusion that under acid-base disturbances a change in aldosterone can not be induced by either renin-angiotensin or ACTH. We suggest that under acid-base disturbances blood pH may be related, at least, in part to changes in aldosterone in humans.

Acid-Base Imbalance↗
PubMed1997

The treatment of enchondromas in the hand by endoscopic curettage without bone grafting.

Nine patients with enchondromas in the hand were treated by endoscopic curettage of the tumour without bone grafting. The procedure was performed on an out-patient basis using axillary block anaesthesia. New bone formation and remodelling of the lesions were observed in all patients. There were no postoperative fractures, infections, recurrences or other complications. Functional recovery was rapid. We conclude that endoscopic curettage without bone grafting is an effective treatment of enchondroma in the hand.

Adolescent↗
PubMed1997

Quasi-steadiness approximation for the two-compartment solute kinetic model.

We analytically solved the equation of the variable volume, two-compartment solute kinetic model (TCSKM). From the solution, we constructed an expression of weekly concentration profiles developing in the patient's body by routine hemodialyses. Obtained formulas can be used to calculate Kt/V, solute reduction index (SRI), the solute generation rate (G) per unit distribution volume (V), and a mass transfer coefficient (MTC) between the two compartments. To estimate these parameters, the formulas only need three-point data during a dialysis, that is, pre-, one-hour, and post-dialysis solute concentrations instead of four that would otherwise be needed. A 48 hour data point is not required. The weekly concentration profiles can be easily calculated by the formulas. As examples of clinical applications, we calculated Kt/V, G/V, and SRI of urea, Cr, and uric acid using plasma data of 121 hemodialyzed patients. Then the results were compared with the single-compartment solute kinetic model (SCSKM). The obtained mean MTC/V values, that is, 1.08 (1/hr) for urea, 0.53 (1/hr) for Cr, and 1.11 (1/hr) for uric acid, were consistent with the previous works. SCSKM overestimated the mean G/V by 7.1%, 15.9%, and 10.0%, and the mean SRI by 6.7%, 18.6%, and 10.0%, for urea, Cr, and uric acid, respectively. The solute distribution volume ratio of TCSKM to SCSKM, (V)TCSKM/(V)SCSKM, depended on the value of MTC/V and the hemodialysis duration. Using pedometers, we measured the total number of steps the patients took during a week. We found that the total number of steps in a week was significantly correlated with the Cr generation rate (r = 0.285, P < 0.03), but that it was not significantly correlated with the other generation rates (r = 0.204, P > 0.09 for urea, and r = 0.209, P > 0.08 for uric acid). These data suggest that the Cr generation rate is related to the patient's physical activity. We conclude that the formulas can estimate an adequate dialysis prescription for the hemodialyzed patient.

Humans↗
PubMed1997

Gliostatin/platelet-derived endothelial cell growth factor as a clinical marker of rheumatoid arthritis and its regulation in fibroblast-like synoviocytes.

The objective was to assess the congruity of gliostatin/platelet-derived endothelial cell growth factor (GLS PD-ECGF) with other clinical markers of rheumatoid arthritis (RA) and to define its molecular mechanism of action in the complicated cytokine network during RA pathogenesis. Immunoassay systems were used to quantify GLS or cytokine levels in laboratory and clinical samples. Expression levels of GLS were determined by reverse transcription-polymerase chain reaction methods. The GLS levels in synovial fluid were correlated with interleukin-1 (IL-1) and IL-8. The serial data of serum GLS levels reflected well changes in the disease activity during the clinical course of four representative patients with RA. In cultured fibroblast-like synoviocytes, tumour necrosis factor-alpha (TNF-alpha), IL-1, IL-6 and IL-8 induced GLS expression. In conclusion, our results suggest that the serum GLS level, mostly derived from cytokine-stimulated synoviocytes, was a useful clinical marker of RA.

Arthritis, Rheumatoid↗
PubMed1997

Protective effects of polysaccharide fucoidin on myocardial ischemia-reperfusion injury in rats.

We tested whether polysaccharide fucoidin, which inhibits leukocyte rolling in the mesenteric venule, has protective effects in the rat myocardial 30-min ischemia and 6-h reperfusion injury model. Intravenous infusion of fucoidin (27 microg/kg/min from 10 min before to 6 h after reperfusion) significantly attenuated myocardial infarct size 6 h after reperfusion. In this ischemia and reperfusion heart model, expression of P-selectin (determined immunohistochemically) was observed on the venular endothelial cells in the heart 30 min after reperfusion and also was sustained after 6 h. Neutrophil infiltration as estimated by myeloperoxidase activity significantly increased 2 h after reperfusion and kept increasing with time until 6 h after reperfusion. Four-hour infusion of fucoidin after reperfusion significantly reduced neutrophil infiltration, whereas the 2-h infusion of fucoidin did not. These results indicate that neutrophil infiltration and myocardial injury are attributed to expression of P-selectin after reperfusion, and that one of the inhibitory mechanisms of fucoidin seems to be blockade of P-selectin-mediated neutrophil rolling on the vessel wall.

Animals↗
PubMed1997

Insulin-like growth factor-binding protein-1 in human follicular fluid: a marker for oocyte maturation.

In order to investigate the role of insulin-like growth factors (IGFs) in human ovulation, we evaluated the concentrations of IGF-binding proteins (IGFBPs) in human follicular fluid (FF). The concentrations of IGFBP-1 in the FFs of 15 women undergoing in vitro fertilization and embryo transfer were measured and related to those of 17beta-estradiol (E2), progesterone and androstenedione in the FFs. IGFBP-1 levels in the FFs were positively correlated with those of E2 and progesterone. No correlation was found between the IGFBP-1 and androstenedione levels in FFs. The concentrations of IGFBP-1 were significantly increased in the FFs which contained mature oocytes compared with those of immature oocytes, whereas IGFBP-3 in FFs tended to decrease as oocytes matured. It is suggested that IGFs may play important roles in human preovulatory processes, and that IGFBP-1 may be a valuable biochemical marker in the evaluation of oocytes.

Androstenedione↗
PubMed1997

Osteoblasts express types I and II activin receptors during early intramembranous and endochondral bone formation.

Increasing evidence suggests a potential role for activin in bone formation. However, the cognate receptors through which activins function with respect to skeletal tissues have not yet been identified. Identification and regulation of expression of these receptors are necessary prerequisites to understanding the role of activins in bone metabolism. We detected mRNAs for three activin receptors, type I (ActRI), type II (ActRII), and type IIB (ActRIIB), in multiple skeletal tissues in rat, including tibia and costochondral growth plate, and also in cultured osteoblasts. To gain information about the relationship between receptor expression and different skeletal cell functions, we evaluated expression of the three receptors in a semiquantitative manner during the early stages of fracture healing, a model for rapid bone formation. Relatively high levels of ActRI and ActRII expression were detected in the callus at 7, 10, and 14 days after fracture, times that correlate with the interval of rapid intramembranous bone formation and the initiation of endochondral bone formation. Expression of the ActRIIB in the fracture callus was strikingly lower than either ActRI or ActRII. Immunostaining of the fracture callus and the newborn rat femur with an anti-ActRII antibody localized the receptor to osteoblasts at regions of membranous and endochondral bone formation. No staining of osteoblasts in fracture callus or bone was seen with an anti-ActRIIB antibody. These results provide strong evidence of the identification of the principal receptors through which activins could function in the skeletal system and further shed light on activin's mechanism of action in bone formation.

Activin Receptors↗
PubMed1997

Changes in urinary excretion of pyridinium cross-links during Spacelab-J.

In SLJ-1 we proposed to study three major objectives. They were; 1. hormonal changes associated with fluid and electrolyte metabolism, 2. the effect of space flight on the circadian rhythms of endocrine and metabolic systems, 3. the changes in the indices of the bone and muscle metabolism during space flight. In this report, the changes in the bone metabolism during Spacelab-J will be presented with a special emphasis on urinary excretion of pyridinium cross-links. Timed urine samples from three Japanese payload specialists were obtained for 3 days from May 19 to 21, 1991 (one year before the launch = L-1 year). Immediately before the launch (L-3 to L-0), urine samples were obtained from a payload specialist who was on board the Space Shuttle Endeavor (PS). During the inflight period (flight from September 3 to 10 in 1992), urine samples from the PS were collected by using Urine Monitoring System (UMS). After the landing, they were obtained from the PS for three days (R+0-R+2). Various parameters related to bone metabolism such as hydroxyproline, pyridinium cross-links and calcium were determined. It was noted that excretion of hydroxyproline decreased during the preflight periods when compared with that in the control L-1 year period. The average excretory rate during control period was 846.2 +/- 198.7 milligrams/hour (mean +/- SD), while those in the preflight 474.6 +/- 171.1 milligrams/hour, suggesting the diminished collagen intake during the preflight period. Average excretion rate of pyridinium cross-links during the first 4 mission days (MD0-MD3) was similar to that of preflight and control L-1 year period. However, it was significantly increased during the last 4 mission days (MD4-MD7). It returned to the preflight level during postflight days (R+0-R+2). Increased urinary excretion of calcium during the last 4 mission days were also observed. These results suggest that increase in bone resorption could occur during relatively short stay in microgravity.

Aerospace Medicine↗
PubMed1997

[Double negative adult T-cell leukemia with hemophagocytic syndrome].

A 79-year-old woman was admitted with general fatigue, jaundice and hepatosplenomegaly. Perpheral blood examination showed 8.0 g/dl Hb, 15 x 10(3)/microliter platelet and 10,490/microliter leukocytes with 86% abnormal lymphocytes. Immunophenotypic analysis of abnormal lymphocytes demonstrated CD2(+), CD3(+/-), CD4(-), and CD8(-). Serum antibody for HTLV-1 was positive. In addition, the monoclonal integration of HTLV-1 proviral DNA into the genome of leukemic cells was demonstrated on Southern blot hybridization. Bone marrow revealed ATL cell in vasion with myelofibrosis and hemophagocytic cell proliferation. Therefore, adult T-cell leukemia with hemophagocytic syndrome was diagnosed. She was treated with methyl prednisolone pulse therapy and gammaglobulin. But she died of hepatic failure 14 days after hospitalization. On autopsy, EB virus LMP-1 was detected in ATL cells in bone marrow. ATL with hemophagocytosis is relatively rare. The association of both pathological states was discussed.

Aged↗
PubMed1996

Identification of a dual leucine zipper kinase involved in rat fracture repair.

Complete cDNA sequence was obtained for a gene found to be expressed at a high level during fracture healing in the rat. Comparison of the amino acid sequence (deduced from the cDNA sequence) with known sequences showed 99% identity with mouse Dual Leucine Zipper Kinase (mDLK) and 96% identity with human Zipper Protein Kinase (hZPK). Relative quantitation by RT-PCR indicates abundant expression of this gene in cultured chondrocytes, growth plate and brain tissue. Further, regulated expression of this gene has been observed during fracture healing in rat femur fracture model; maximum gene expression in this model appears to coincide with chondrogenesis and bone formation. Since DLK has been shown to function in the mitogen activated signaling (MAP) pathway, these results provide the first evidence for the involvement of this signaling pathway in fracture healing.

Amino Acid Sequence↗
PubMed1996

Changes in responses of wide dynamic range neurons in the spinal dorsal horn after dorsal root or dorsal root ganglion compression.

STUDY DESIGN: The electrophysiologic responses of wide dynamic range neurons in the spinal dorsal horn by compression of the dorsal root or of the dorsal root ganglion were investigated. OBJECTIVES: This study identified differences between the compression of the dorsal root against the compression of the dorsal root ganglion by examining the responses of wide dynamic range neurons. SUMMARY OF BACKGROUND DATA: The wide dynamic range neurons studied were known to be excited by primary afferent fibers, not only combined A delta and C-nociceptive fibers but also low threshold mechanoreceptive A beta fibers and A delta fibers of down hairs. Thus, the wide dynamic range neurons are classified as nociceptive neurons. METHODS: Extracellular activities of 32 wide dynamic range neurons were recorded from the laminae 4-6 of the seventh lumbar cord in anesthetized cats. A microvessel clip (40 g) was applied to compress the dorsal root or the dorsal root ganglion. RESULTS: Dorsal root compression produced only an initial burst (about 10-40 seconds). Prolonged repetitive firings were rarely maintained. In contrast, dorsal root ganglion compression resulted in a maintained repetitive firing throughout the period of compression. After release of compression of the dorsal root and the dorsal root ganglion, responses to brushing were facilitated, and the low threshold center of the receptive field expanded. CONCLUSIONS: These findings are consistent with the previous report that the radicular pain associated with a herniated intervertebral disc initially results from compression of the dorsal root ganglion.

Animals↗