Search PubMed⌕ Search

Biomedical subjects

K Kurisu

Publications and source records attributed to K Kurisu.

At least 289 records · Page 16Linked to original sources

[Effects of open-heart surgery on renal function].

Effects of open-heart surgery on renal function were studied in 38 patients who had uneventful postoperative course with no sign of acute renal failure. Of these, 19 underwent aorto-coronary bypass grafting (Group 1) and 19 underwent valve replacement (Group 2). During cardiopulmonary bypass (CPB), renal plasma flow (RPF) and glomerular filtration rate (GFR) significantly decreased in both groups as compared to the preoperative values. The decreased GFR remained significantly low on the day of operation in both groups and returned to the preoperative level on the 1st postoperative day (POD) in group 1 and on the 3rd POD in group 2. On the other hand, plasma antidiuretic hormone (ADH) level markedly increased during CPB and remained significantly higher than the preoperative level through the 1st POD. Despite the decreased GFR and increased ADH, however, urinary flow markedly increased during CPB in both groups and remained at significantly higher level than the preoperative values through the 3rd POD in group 1 and through the 5th POD in group 2. Fractional excretion of sodium significantly increased during CPB in both groups and remained high through the 1st POD in group 1 and through the 3rd POD in group 2. These data demonstrate that the renal function of urine concentration is disturbed in the early phase following open-heart surgery even in the patients who have uneventful postoperative course.

Adult↗

Immunofluorescence localization of type I and type III collagen and fibronectin in mouse dental tissues in late development and during molar eruption.

Affinity-purified antibodies produced intense staining for type I collagen in alveolar bone matrix and predentine, and moderate staining in the dentine matrix, lamina propria, connective tissue invaginating into papillary layer of the enamel organ, dental sac and periodontal ligament. No staining occurred in oral epithelium, stellate reticulum, stratum intermedium, ameloblasts and odontoblasts. Fibronectin was distributed similarly except at the interface between the epithelial diaphragm and pre-odontoblasts where type I collagen was absent but fibronectin was present. In contrast, type III collagen showed strong staining in the periodontal ligament and lamina propria but no staining in bone matrix, predentine, dentine and at the interface between the epithelial diaphragm and pre-odontoblasts. The staining pattern for type III collagen was similar to that of type I and fibronectin in other tissues including endosteal reticular tissue, the connective tissue invaginating into papillary layer and the extracellular matrix of the pulp.

Alveolar Process↗

Effects of retinoic acid on receptors for epidermal growth factor in mouse palatal mesenchymal cells in vitro.

Retinoic acid (RA), one of the inducers of cleft palate in vivo, specifically increased the 125I-epidermal growth factor (EGF) binding capacity of embryonic palatal mesenchymal cells; the increase was completely inhibited by actinomycin D, suggesting that transcription is required for this change. When the increase in EGF receptors was related to the stimulation of DNA synthesis by EGF in the presence of various concentrations of RA, the maximum stimulation of [3H]-thymidine by EGF was at 10(-9) M RA, but the maximum increase in the number of EGF receptors was at 10(-6) M RA. Thus the increase in the number of EGF receptors cannot be related to EGF-stimulated DNA synthesis.

Animals↗

Immunocytochemical demonstration of simultaneous synthesis of types I, III and V collagen and fibronectin in mouse embryonic palatal mesenchymal cells in vitro.

An immunocytochemical study was made on the palatal mesenchymal cells obtained from mouse embryos during palatal development with special reference to synthesis of types of collagen and fibronectin in vitro. Most cells showed positive staining with antibodies against the four proteins examined. The staining for type I collagen was most intense among the four proteins and was distributed perinuclearly. The staining for type III collagen was quite similar as that for type I collagen but less intense, whereas that for type V collagen was weak and its staining pattern was different from those for types I and III collagen in that the surface of the plasma membrane, in addition to the perinuclear cytoplasm, showed weak staining for type V collagen. Antibodies to fibronectin showed perinuclear and extracellular fibrous staining. These data suggest that palatal mesenchymal cells synthesize types I, III, and V collagen and fibronectin simultaneously.

Animals↗

Immunoelectron microscopic localization of fibronectin in the smooth muscle layer of mouse small intestine.

We studied the ultrastructural distribution of fibronectin in the smooth muscle layer of mouse small intestine with affinity-purified antibodies using the immunogold technique. Fibronectin was present over the pericellular area extending from the cell membrane to the extracellular matrix beyond the basal lamina. Distribution of the glycoprotein over the pericellular area was heterogeneous, i.e., it was localized more abundantly in the narrow space between smooth muscle cells, the gaps having a width of 60-80 nm where the two dense bands in adjacent cells matched each other. Such localization suggests that fibronectin contributes to cell adhesion. Within the basement membrane, gold label was localized both in lamina lucida and lamina densa, more densely in the latter than in the former. Fibronectin was also co-distributed with collagen fibers in the extracellular matrix. Within smooth muscle cells, gold particles were observed on rough endoplasmic reticulum and secretory vesicle-like structures. These results suggest that smooth muscle cells synthesize fibronectin and secrete it as a component of the basal lamina and extracellular matrix.

Animals↗

Ossified prolactinoma: case report.

The authors report a case of ossified prolactinoma that was identified as a calcified nodule on the roentgenograms. Histologically, the ossified tissues were diffuse, and the osteoid was mineralized in various degrees, subsequently forming bones. Adenoma cells were sparse among the ossified tissues. This is probably the first report of ossified pituitary adenoma associated with osteoid metaplasia. The pathogenesis of osteoid metaplasia in pituitary adenomas is possibly due to proliferative connective tissue resulting from degeneration of the pituitary adenoma; this connective tissue may possess osteogenic potency.

Adult↗

Effect of retinoic acid on in vitro proliferation activity and glycosaminoglycan synthesis of mesenchymal cells from palatal shelves of mouse fetuses.

To clarify the mechanism by which retinoid causes cleft palate, we investigated the effect of retinoic acid (RA) on proliferation activity and glycosaminoglycan (GAG) synthesis in mouse fetuses palatal mesenchymal (MFPM) cells. MFPM cells were incubated for 1-11 days with various concentrations of RA to examine its effect on growth rate. Also, confluent cultures were incubated with [3H]glucosamine or [35S]sulfate in the presence of various concentrations of RA to investigate the effect of RA on GAG synthesis. RA remarkably inhibited the growth of MFPM cells in a dose-dependent manner. RA also inhibited the synthesis of GAGs, with sulfated GAGs being more severely affected than hyaluronic acid. These data suggest that the inhibition of proliferation activity and GAG synthesis of palatal mesenchymal cells might be involved in the induction of cleft palate by retinoic acid.

Animals↗

Normal bone marrow adherent cell-conditioned medium corrects the impaired differentiation of cultured mononuclear phagocytes from vitamin D-deficient rats.

There is increasing evidence that 1,25 dihydroxyvitamin D3 acts directly to differentiate and activate cells of mononuclear phagocyte lineage (MNP). However, it seems possible that in bone marrow this hormone may modulate the differentiation of MNP via the factor elaborated by the stromal cells or the macrophages. We tested this hypothesis using two separate culture systems of bone marrow cells from vitamin D-replete (D+) and -deficient (D-) rats. The animals were maintained from the third day of lactation on D+ or D- diet for up to 105 days. In vivo studies showed that the long-term D- state resulted in a depletion of acid phosphatase-positive macrophagelike cells and osteoclasts in bones. After a 14 day incubation period, cultures of D- bone marrow cells contained an increased number of fibroblastoid cell colonies and a reduced number of macrophages attached to fibroblastoid cells, compared with the controls. When D+ bone marrow cells were cultured for 4 days in the presence of supernatants obtained from 14 day cultures of D- bone marrow (marrow adherent cell-conditioned medium, MACCM), the differentiation of MNP into macrophages was inhibited. Impaired differentiation was almost complete in D- bone marrow cell cultures to which D- MACCM was added. These cultures consisted of only 6.6% macrophages compared with 53.9% in the control cultures. However, when D- bone marrow cells were cultured with D+ MACCM, differentiation was restored and 75.4% of the cells were macrophages. These results suggest that a paucity of macrophages and osteoclasts in D- rats is in part, if not entirely, a result of a failure of stromal cells and/or macrophages in the bone marrow to release a factor(s) necessary for differentiation of MNP and osteoclast precursors.

Animals↗

Interaction between epidermal growth factor and triamcinolone acetonide in mouse palatal mesenchymal cells in vitro.

Palatal mesenchymal cells from mouse embryos (MEPM cells) had a high number of specific receptors for epidermal growth factor (EGF). At 37 degrees C, the number of high-affinity receptors (dissociation constant, Kd of 6.0 X 10(-10) M) was 2.0 X 10(5) per cell and of low-affinity receptors (Kd of 2.9 X 10(-9) M), 3.8 X 10(5) per cell. At 2 degrees C, a single class of receptors (Kd of 4.8 X 10(-9) M) was detected at 1.8 X 10(5) per cell. Triamcinolone acetonide, a potent cleft-palate-inducing agent, slightly inhibited the recovery of 125I-labelled EGF binding capacity in MEPM cells after down regulation of EGF receptors; it did not affect the binding properties of 125I-labelled EGF in these cells.

Animals↗

Effect of glucocorticoid on glycosaminoglycans synthesis in cultured mouse embryonic palatal mesenchymal cells.

The effect of glucocorticoids (GC) on the synthesis of glycosaminoglycans (GAGs) in mesenchymal cells obtained from palatal shelves of mouse embryos was studied. Both hyaluronic acid (HA) synthesis and sulfated GAG synthesis were inhibited with triamcinolone acetonide (TA) in a concentration-dependent manner. However, the degree of inhibition of synthesis with TA was greater for HA than for the sulfated GAGs. To determine whether the inhibitory effects of TA on HA and sulfated GAGs synthesis were mediated through GC receptors, we performed experiments using progesterone, vitamin B6, and molybdate. The inhibitory effect of TA was antagonized by all three. The results obtained in the present study suggest that the inhibition of synthesis of HA and sulfated GAGs with GC is mediated through GC receptors and is involved in cleft palate induction by GC.

Animals↗

[Skull base metastasis of prostatic cancer presenting as exophthalmos--a case report].

A 72-year-old man was admitted to our hospital complaining of diplopia and right exophthalmos. Craniography and CT scan showed thickening of the right orbital roof and no intracranial lesion. Total acid phosphatase and prostatic acid phosphatase were high. Bone scintigraphy revealed high uptake at that lesion and the right pelvis. Unroofing of the right orbit and opening of the optic canal were performed in order to reduce intraorbital pressure. Microscopic examination revealed a metastatic lesion of prostatic cancer. Postoperatively, the patient was treated with "Honvan" and the course has been good.

Aged↗

Immunocytochemical study of collagen in epidermal growth factor (EGF)-treated osteoblastic cells.

The alteration of collagen components in clone MC3T3-E1 cells by epidermal growth factor (EGF) was investigated immunocytochemically, using antibodies to type I and type III collagens. EGF transformed those cells that had become more slender than those of control cultures. Type I and type III collagens were observed in the same cells in both EGF-treated and control cultures. Type I collagen was decreased by EGF, whereas type III collagen appeared to be increased. However, no cells with only type III collagen were observed, suggesting that EGF influences collagen metabolism in clone MC3T3-E1 cells.

Animals↗

Effects of epidermal growth factor on osteoblastic cells in vitro.

The effect of epidermal growth factor (EGF) on clone MC3T3-El cells that have osteoblastic activity was examined by phase-contrast microscopy and electron microscopy; hydroxyproline content, collagen synthesis, collagen pattern, and alkaline phosphatase (ALP) activity were also determined. We found that EGF (0.4 ng/ml) transformed the cells from their normal polygonal shape to a spindle-like morphology by 8 h. This hormone also caused dose-related suppression of hydroxyproline content and ALP activity which was detectable 2 days and 1 day, respectively, after EGF addition. Indomethacin did not affect hydroxyproline content and ALP activity, suggesting that the effect of EGF on the cells may not be mediated by prostaglandins. Epidermal growth factor at concentrations of 2 to 50 ng/ml significantly decreased collagen synthesis in the cells, whereas protein synthesis was stimulated. Electron microscopy demonstrated that collagen fiber formation was also reduced by EGF; an immature type of fibril was observed compared with the typical cross-striated one in the controls. Moreover, the hormone treatment also resulted in the appearance of type III collagen in addition to the type I already present in the cells. These suppressive effects of EGF on MC3T3-El cells in vitro suggest that this hormone may be involved in bone remodelling in vivo as well.

Alkaline Phosphatase↗

Effect of triamcinolone acetonide on proliferation and collagen and glycosaminoglycan syntheses in palatal mesenchymal cells from the mouse fetus.

The present study was performed 1) to demonstrate the direct effects of triamcinolone acetonide (TA) at various concentrations on mouse fetal palatal mesenchyme (MFPM) cells with special reference to proliferating activity and collagen and glycosaminoglycan syntheses, and 2) to determine whether the effects of TA were glucocorticoid (GC) receptor-mediated. A low concentration of TA (10(-10) M) stimulated proliferating activity and hyaluronic acid (HA) synthesis. As TA concentrations were increased, proliferating activity and collagen synthesis were suppressed in a concentration-dependent manner, with especially marked suppression occurring at 10(-7) -10(-5) M. Rather mild reductions were observed in the rates of HA and total cellular protein synthesis. Further, it was demonstrated that MFPM cells have a single population of specific, high-affinity, saturable GC receptors which have an apparent dissociation constant (Kd) of 17 nM; and there are 24.2 X 10(4) binding sites per cell. Moreover, antagonistic effects of progesterone were observed on proliferating activity and collagen synthesis, suggesting that the responses of the cells to GC are receptor-mediated. The results show that MFPM cells are capable of responding to both physiological and pharmacological levels of GC directly, suggesting that either endogenous or exogenous high levels of GC may have the potential to interfere with mouse palate formation by perturbing the proliferating activity and synthesis of macromolecules in palatal mesenchymal cells.

Animals↗

An effective fixative for glucocorticoid receptors in fetal tissues.

As a preliminary study in an autoradiographic study of glucocorticoid (GC) receptor localization in orofacial tissues of mouse fetuses, a search was made to determine the most effective fixative for preservation of the GC-receptor complex. Twelve-day-old mouse fetuses were administered tritiated triamcinolone acetonide (3H-TAC) intraamniotically and subsequently processed by one of the following three procedures: freeze-drying, prefixation with Karnovsky's fixative, or "the catechin fixative" (Karnovsky's fixative containing 1% D-catechin) and postfixation with osmium tetroxide. Light microscopic autoradiography and liquid scintillation counting of the specimens revealed that the catechin fixative gave the best results for fixation of the steroid-receptor complex and preservation of tissue structure. Light and electron microscopic autoradiographic studies of the time course of the localization of 3H-TAC in palatal shelves supported the catechin fixative as being the most effective in preservation of GC-receptor or ligand complexes.

Animals↗