Modification by magnesium of the excitatory effect of oxytocin on electrical and mechanical activities of pregnant human myometrium.
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Electrophysiology↗
Biomedical subjects
S Kanda
Publications and source records attributed to S Kanda.
Effects of cytokines on the growth of cultured rabbit renal cortical tubular cells.
The effects of various cytokines including interleukin-1 beta, -2, and -6, tumor necrosis factor-alpha, and granulocyte-macrophage colony stimulating factor on the DNA synthesis of cultured rabbit renal cortical tubular cells were investigated. Among these cytokines, it was found that only interleukin-1 beta could stimulate the DNA synthesis of cultured renal tubular cells, while interleukin-6 mildly suppressed the DNA synthesis of such cells. Interleukin-1 beta and -6 are produced by mesangial cells. The above results suggest that these cytokines may regulate the growth of tubular cells via the urinary flow in the nephron.
Animals↗
Hepatocyte growth factor is a potent mitogen for cultured rabbit renal tubular epithelial cells.
Hepatocyte growth factor (HGF), which is a potent growth factor of adult rat hepatocytes in primary culture, also strongly stimulated DNA synthesis of rabbit renal tubular epithelial cells in secondary culture. Its mitogenic activity was dose-dependent, being detectable at 3 ng/ml and maximal at 30 ng/ml. Over 20% of the cells were shifted to the S-phase by HGF alone, judging by the labeling index. HGF had additive effects with EGF, acidic fibroblast growth factor (a-FGF), and insulin. Transforming growth factor-beta 1 (TGF-beta 1) strongly inhibited DNA synthesis of renal tubular cells stimulated by HGF. The growth of renal tubular epithelial cells was also regulated by cell density: DNA synthesis stimulated by HGF was high at lower cell density and was strongly suppressed at high cell density. These results suggest that HGF may act as a renotropic factor in compensatory renal growth or renal regeneration in vivo.
Animals↗
Testicular development in Chinese Meishan boars.
The developmental process of the testis and age-related changes in the morphology of rete testicular spermatozoa were investigated in Meishan boars at 1 to 364 days of age. Testicular weight and the diameter of seminiferous tubules increased rapidly until 150 to 180 days of age. Leptotene stage spermatocytes, round spermatids and spermatozoa were first found in the section of seminiferous tubules at 30 to 45, 60 and 75 days of age, respectively. However, after 105 to 120 days of age, most rete testicular spermatozoa were morphologically normal. These results indicate that Meishan boars reach puberty as early as 75 days of age, though the testes acquire the ability to produce morphologically normal spermatozoa at about 120 days.
Journal Article↗
Computed tomography of maxillofacial infection.
Eighteen patients with maxillofacial infections, who had trismus and swelling of the masseteric region, were investigated by CT. Spread of infection was evaluated with particular reference to the fascial spaces. The masticator space was divided into four parts and the changes in each were assessed together with the surrounding fascial spaces. There were changes in the masseter muscle and infection had spread into the upper parts of the masticator space in more than half of the patients. There was a fall in the CT value in the affected muscles, whereas it was raised in the parotid gland and adipose tissue. The clinical importance of CT is shown to have a significant role in the diagnosis and follow-up of maxillofacial infections.
Adipose Tissue↗
Transient increase in renal epidermal growth factor content after unilateral nephrectomy in the mouse.
A sensitive enzyme-linked immunosorbent assay for mouse epidermal growth factor was established for measurement of the content of epidermal growth factor in the remaining kidney after uninephrectomy. In 5-week-old male mice, the renal epidermal growth factor content before uninephrectomy was 355 +/- 97 ng/g wet tissue with a 2.1-fold increase on the first day after uninephrectomy, whereafter it gradually decreased. In 15-week-old mature male mice, the renal epidermal growth factor content increased 1.7-fold on the first day after uninephrectomy. Immunohistochemical analysis showed that epidermal growth factor was present in the distal tubular cells and that the staining intensity was increased on the first day after uninephrectomy. During the course of compensatory renal growth, no significant alteration of epidermal growth factor content was observed in plasma or in the submaxillary gland. Our data suggest that the increase in renal epidermal growth factor content after uninephrectomy is due to an increased production of epidermal growth factor in the kidney itself. The significance of this phenomenon is discussed.
Animals↗
[Echocardiographic manifestations of excessive pulmonary artery banding in patients with transposition of the great arteries without ductal or ventricular shunt].
Recently, pulmonary arterial banding (PAB) and the Blalock-Taussig shunting operation (B-T) have been performed as a preparatory procedure for Jatene's operation for patients with complete transposition of the great arteries (TGA) without patent ductus arteriosus (PDA) or ventricular septal defect (VSD). We reviewed the echocardiographic findings of 29 patients after PAB and B-T. Four cases had abnormal catheterization data after PAB and B-T (Group 1). Twenty-five control cases with successful two-stage Jatene's operation exhibited normal data (Group 2). We studied 1) the grade of distortion of the interventricular septum as the a/b ratio on two-dimensional echocardiogram (2-DE), 2) the left ventricular (LV) shortening fraction (LVSF), 3) the thickening fraction (ThF), 4) the LV posterior wall thickness in diastole (LVPWTd) on M-mode echocardiogram, and 5) the LV inflow tract (LVIT) flow pattern on pulsed Doppler echocardiogram. In Group 1, all cases revealed LVSF less than 0.19 (control group: 0.40-0.56), ThF less than 0.18 (control group: 0.43-0.81), the a/b ratio higher than 0.88 (control group: 0.53-0.79), and LVPWTd thicker than 0.67 cm (control group: 0.45-0.59 cm). These data are markedly deviated from the range of the control data (p < 0.01). All cases in Group 1 had LVIT flow lacking the rapid filling phase, which was recognized in the control group. These abnormal echocardiographic findings suggest LV failure in adaptation against excessive after-load due to very tight PAB, and these figures are very different from the control group. These unusual postoperative cardiac abnormalities can be detected noninvasively using 2-DE and Doppler echocardiography.(ABSTRACT TRUNCATED AT 250 WORDS)
Echocardiography↗
The expression of actin mRNA in megakaryocytes demonstrated in paraffin sections, and epoxy resin semi-thin and thin sections by in situ hybridization.
Megakaryocytes of dog bone marrow were utilized as target cells for identifying actin mRNA expressing cells on semi-thin and thin sections. After in situ hybridization with radioisotope-labeled probes was performed on paraffin sections, gelatin capsules containing freshly prepared epoxy resin were placed on the sections. The resin was solidified and detached from the slide glass, and semi-thin and thin sections were obtained. The signals showing actin mRNA expression were detected on megakaryocytes in these sections by light and electron microscopy.
Actins↗
Salivary SPECT and factor analysis in Sjögren's syndrome.
Salivary SPECT and factor analysis in Sjögren's syndrome were performed in 17 patients and 6 volunteers as controls. The ability of SPECT to detect small differences in the level of uptake can be used to separate glands from background even when uptake is reduced as in the patients with Sjögren's syndrome. In control and probable Sjögren's syndrome groups the uptake ratio of the submandibular gland to parotid gland on salivary SPECT (S/P ratio) was less than 1.0. However, in the definite Sjögren's syndrome group, the ratio was more than 1.0. Moreover, the ratio in all patients with sialectasia, which is characteristic of Sjögren's syndrome, was more than 1.0. Salivary factor analysis of normal parotid glands showed slowly increasing patterns of uptake and normal submandibular glands had rapidly increasing patterns of uptake. However, in the definite Sjögren's syndrome group, the factor analysis patterns were altered, with slowly increasing patterns dominating both in the parotid and submandibular glands. These results suggest that the S/P ratio in salivary SPECT and salivary factor analysis provide additional radiologic criteria in diagnosing Sjögren's syndrome.
Adult↗
Sensitive assay system for bile acids and steroids having hydroxyl groups utilizing high-performance liquid chromatography with peroxyoxalate chemiluminescence detection.
3 alpha- or 3 beta-hydroxysteroids, such as bile acids (free and glycine and taurine conjugates), 3 beta-hydoxy-5-cholenic acid, pregnanediol, 5-pregnene-3 beta, 20 beta-diol and 5-pregnene-3-beta,20 alpha-diol, were converted to 3-oxosteroids by enzymatic reaction using immobilized hydroxysteroid dehydrogenase, derivatized with dansylhydrazine to the corresponding dansyl hydrazones and purified by gel permeation chromatography. The dansyl hydrazones were chromatographed on a C18 column with a tetrahydrofuran-containing eluent and detected at the level of a few femtomoles by a peroxyoxalate chemiluminescence post-column reaction using bis[4-nitro-2-(3,6,9-trioxadecyloxycarbonyl)phenyl] oxalate as a chemilumigenic reagent. The dansyl hydrazones of chenodeoxycholic acid and deoxycholic acid (free and glycine and taurine conjugates) in particular, which coeluted under the chromatographic conditions above, were separated using an eluent including acetonitrile and 2,6-di-O-methyl-beta-cyclodextrin and detected in the same way.
Bile Acids and Salts↗
Studies on the effects of imidazole on the peroxyoxalate chemiluminescence detection system for high performance liquid chromatography.
The catalytic effect of bases (imidazole, pyridine, Tris and triethylamine) on the peroxyoxalate chemiluminescence (PO-CL) reaction for high performance liquid chromatography (HPLC) was investigated. Imidazole increased PO-CL intensity extraordinarily, whereas the other bases (pyridine, Tris and triethylamine) did not. The peak heights of dipyridamole (coronary vasodilator) obtained using the eluents containing buffers were largest at pH 7.0, a few times less at pH 6.0 and pH 5.0, 100 times less at pH 4.0 and a few hundred times less at pH 3.0. The eluents containing buffers at pH 3, 4, 5, 6 or 7 each with imidazole increased the peak heights by a few to ten times as compared with those without imidazole, and those peak heights were within one order of magnitude. On the other hand, the eluent containing buffer at pH 2 did not affect the peak heights with or without imidazole. Bis(4-nitro-2-(3,6,9-trioxadecyloxycarbonyl)phenyl) oxalate (TDPO) alone and bis(2,4-dinitrophenyl)oxalate (DNPO) plus TDPO were recommended to be used against eluents containing buffers of pH 5-7 and pH 3-4, respectively. Dipyridamole and benzydamine hydrochloride (anti-inflammatory drug) were separated on the ODS column and detected by the present system. The detection limits of dipyridamole and benzydamine hydrochloride were 40 amol and 270 fmol, respectively.
Chromatography, High Pressure Liquid↗
A new method for the high performance liquid chromatographic determination of TA-870, a dopamine prodrug (catechol ester compound).
A new method for the high performance liquid chromatographic (HPLC) determination of N-(N-acetyl-L-methionyl)-O,O-bis(ethoxycarbonyl)dopamine (TA-870), a dopamine prodrug, in biological fluid has been developed. In order to measure with an electrochemical detector (ECD), TA-870 was passed first through an immobilized carboxylesterase column to be converted to the electrochemically active deethoxycarbonylated TA-870 (DEC-TA-870). The properties of this carboxylesterase immobilized on Sepharose 4B were examined by this flow injection system. Hydrolysis of TA-870 with this immobilized carboxylesterase was a maximum at pH 7-8 and 50 degrees C, and the activity decreased in the presence of organic solvent such as acetonitrile. For the determination of TA-870 in biological fluids, an HPLC-immobilized enzyme-ECD system using a column-switching technique was developed. The blood was deproteinized with ethanol, and TA-870 in the ethanol extracts was adsorbed in Bond Elut C18. The dichloromethane eluate from Bond Elut C18 was injected into the HPLC system. The HPLC apparatus was composed of three pumps, two separation columns (LiChrosorb Si 60 and mu Bondasphere), a trap column (Bond Elut), an enzyme column, ECD and the column-switching system. The calibration curve for TA-870 in blood was linear in the range from 2 to 200 ng/mL. This new assay method might be useful also for the determination of other catechol ester compounds.
Animals↗
Transforming growth factor beta-like activity in human hydrocele fluid.
In this study transforming growth factor beta (TGF-beta)-like activity in human hydrocele fluid was investigated. Inhibition of DNA synthesis of adult rat hepatocytes in primary culture and stimulation of colony formation of normal rat kidney (NRK) fibroblasts, clone 49F in soft agar were observed in all acidified hydrocele fluids and these activities were neutralized by the specific antibody raised against human native TGF-beta. In samples obtained from recurrent cases of hydrocele, TGF beta-like activity was observed in its active form (without acidification). These results suggest that human hydrocele fluid contains TGF beta-like activity and that the active form of TGF-beta in recurrent hydrocele fluid may be responsible for the recurrence of the disease even after repeated aspiration.
Animals↗
Some electrical properties of human pregnant myometrium.
Membrane properties of the human pregnant myometrium were investigated with the conventional microelectrode and patch clamp methods. The majority of preparations produced spontaneous action potentials at a very low frequency, and action potentials were inhibited in sodium-deficient or calcium-free solutions. With the patch clamp technique with 120 mmol/L cesium-20 mmol/L tetraethylammonium in the pipette, the inward current was evoked by a depolarizing pulse above -40 mV from a holding potential of -60 mV and maximum amplitude was obtained at 0 mV. At a holding potential of -100 mV, the inward current could be evoked with less positive depolarizing pulses, and the membrane potential that evoked the maximum amplitude of inward current was shifted to a more negative potential. Single-channel current recording revealed that two types of calcium channels existed in human pregnant myometrium, with single-channel conductances of 12 and 29 pS. One of the calcium channels (12 pS) was inactivated at a holding potential of -60 mV.
Action Potentials↗
Ovarian development in Meishan pigs.
Ovaries collected from a total of 35 Meishan gilts of various ages were morphologically and histologically examined. Vesicular follicles were first observed in ovarian sections at 45 d of age. Simultaneously, protruding follicles appeared on the surface of the ovaries, and then ovarian weight increased rapidly with an increasing number of protruding follicles. About half of the gilts between 75 and 90 d of age had ovaries with corpora lutea, indicating that some of them had started estrous cycles before reaching 75 d of age. In Meishan gilts treated with exogenous gonadotropins, ovaries were stimulated as early as 45 d of age. These results suggest that the precocity of Meishan gilts may include the development of vesicular follicles in the ovaries at an early age.
Journal Article↗
The effect of transforming growth factor-beta on the alkaline phosphatase activity in rabbit renal cortical tubular cell cultures.
The effect of various growth regulators including epidermal growth factor and transforming growth factor-beta on the alkaline phosphatase activity of rabbit renal cortical tubular cells has been investigated in a serum-free culture. As a result, it was found that transforming growth factor-beta, known to be a growth inhibitor of renal tubular cells, increased the alkaline phosphatase activity of the tubular cells dose-dependently and that cycloheximide blocked any increase in the activity of this factor. In contrast, epidermal growth factor decreased the alkaline phosphatase activity in the tubular cells.
Alkaline Phosphatase↗
A study of growth regulators of renal cortical tubular cells in the rabbit liver.
Two growth regulators, a growth stimulator for cultured renal tubular cells and a growth inhibitor, were observed in this study in rabbit liver homogenate after a unilateral nephrectomy. These regulators appeared in the liver on the third day after this nephrectomy, decreased on the seventh day, and disappeared by the fourteenth day. The growth stimulatory activity, termed a tubular cell growth factor (TuCGF), was a heat- and acid stable 15 to 20 KDa protein. The additive effects of TuCGF on the epidermal growth factor (EGF), the insulin-like growth factor-I (IGF-I), and the fibroblast growth factor (FGF) were observed; the results suggest that TuCGF differs from EGF, IGF-I, or FGF. In contrast, the growth inhibitory activity, termed a tubular cell growth inhibitor (TuCGI), was a heat- and acid-labile protein with a molecular weight of about 150 to 200 KDa. This factor potently inhibited the DNA synthesis of tubular cells in the presence of insulin and EGF. These results suggest that TuCGI is not identical with transforming growth factor-beta (TGF-beta). The regulation of these activities by target cell density is also discussed.
Animals↗
Identification of a protein increasing in serum of Nagase analbuminemic rats bearing intestinal tumors as an isotype of T-kininogen.
Increase in an unidentified protein was observed in serum of Nagase analbuminemic rats (NAR) bearing intestinal tumors induced by azoxymethane. This protein seemed to be a polymer of a protein of 73 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and so was tentatively named 73K-protein. The serum concentration of 73K-protein in NAR bearing intestinal tumors was 11.9 +/- 2.2 mg/ml (mean +/- SD, n = 5), whereas that in control NAR was 2.0 +/- 0.2 mg/ml. Increase of the serum 73K-protein level was also observed in Sprague-Dawley rats bearing intestinal tumors, skin tumors, subcutaneous sarcomas, or mammary tumors and in ACI rats bearing urinary bladder tumors. On double immunodiffusion analysis, the 73K-protein was not detected in mouse, guinea pig, pig, horse, or human serum. A cDNA clone bearing the sequence encoding 73K-protein was isolated from a cDNA library constructed from rat liver mRNA. The nucleotide sequence of the 73K-protein showed 98.8% and 96.9% homologies with the sequences of the 3'-proximal domains of the cDNAs for TI- and TII-kininogen, respectively. Therefore, the 73K-protein was concluded to be an isotype of T-kininogen.
Amino Acid Sequence↗