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K Yanagida

Publications and source records attributed to K Yanagida.

At least 73 records · Page 4Linked to original sources
PubMed1991

Thermostability of sperm nuclei assessed by microinjection into hamster oocytes.

Nuclei isolated from spermatozoa of various species (golden hamster, mouse, human, rooster, and the fish tilapia) were heated at 60 degrees-125 degrees C for 20-120 min and then microinjected into hamster oocytes to determine whether they could decondense and develop into pronuclei. Mature, mammalian sperm nuclei, which are stabilized by protamine disulfide bonds, were moderately heat resistant. For example, they remained capable of pronucleus formation even after pretreatment for 30 min at 90 degrees C. Indeed, a temperature of 125 degrees C (steam) was required to inactivate hamster sperm nuclei completely. On the other hand, nuclei of rooster and tilapia spermatozoa and those of immature hamster and mouse spermatozoa, which are not stabilized by protamine disulfide bonds, were sensitive to heating; although some of them decondensed after exposure to 90 degrees C, none formed male pronuclei. Furthermore, nuclei of mature hamster sperm became heat labile when they were pretreated with dithiothreitol to reduce their protamine disulfide bonds. These observations suggest that the thermostability shown by the nuclei of mature spermatozoa of eutherian mammals is related to disulfide cross-linking of sperm protamines.

Animals↗
PubMed1991

[Kinetics of immune complex deposition and influence of decomplementation on their clearance in cationized antigen induced acute serum sickness].

Using a murine acute serum sickness model caused by cationized bovine gamma-globulin (CBGG), the histological findings, accumulation of CBGG in the organs and the effect of decomplementation for the clearance of immune complex (IC) were investigated. The accumulation of CBGG increased in the lungs in the presence of anti-CBGG antibody 1 hour after injection of CBGG, but did not change in the kidneys. This suggests that CBGG forms IC in situ in the kidneys, and that circulating IC accumulates in the lungs. Decomplementation did not influence the uptake of CBGG immediately after challenge but delayed the clearance of CBGG in the kidneys, lungs, liver and spleen. A beneficial role of the complement system in the clearance of IC even for those formed in situ was recognized. Histological changes, cellular infiltration and microvascular destruction, evoked in the lungs in this experimental model immediately after challenge, were not seen in the kidney, suggesting the different modes of complement activation in these organs.

Animals↗
PubMed1991

[The relationship between complement C3 receptors (CR1, CR3) on polymorphonuclear leukocytes and complement fragments during hemodialysis].

The expression of complement receptor type 1 (CR1) and type 3 (CR3) on polymorphonuclear leukocytes (PMNs) and generation of complement fragments, C3a, C5a, C4d, iC3b and Bb, were studied in patients during hemodialysis using cuprammonium rayon (Cu) membranes. Furthermore, the relation between the expression of CR1 and CR3 on PMNs from healthy donors and complement fragments was investigated. The expression of CR1 and CR3 on PMNs increased during hemodialysis. Plasma C3a, C5a and iC3b levels increased in the first 15 minutes and then decreased at 120 minutes of dialysis. But plasma Bb level remained high until the end of hemodialysis. Purified Bb had no effect on the expression of CR1 and CR3 on PMNs, but C5a augmented those expression in vitro. Nafamostat mesilate, an artificial proteinase inhibitor, inhibited augmentation of complement receptors on PMNs in concentration dependent fashion. C5a generated through the activation of complement was thought to take an important role in the increased expression of CR1 and CR3 on PMNs.

Aged↗
PubMed1991

[Complement fragments in patients with bronchial asthma].

In this study, we investigated the pharmacological reactions induced by ibudilast to the complement system with the aim of clarifying the functional relation of the complement system to allergic reactions and pathology in patients with bronchial asthma. Complement hemolytic activities (CH50 and ACH50), complement profile, anaphylatoxins (C3a and C5a) and complement fragments (Bb, iC3b and C4d) were measured in 20 patients with bronchial asthma. One of antiasthmatic activities induced by ibudilast was concluded to be brought about though inactivation of the alternative complement pathway working on type III allergic reaction. Ibudilast increased the complement fragment Bb in the patients' plasma with the fairly controlled bronchial asthma. This increase in circulating Bb was suspected to be a result of inactivation of intermediate complement complexes, for example C3b.Bb.P, because the amounts in plasma of C3 and C5 showed no changes, while those of factor, B, P, H and I were decreased by ibudilast administration in patients with fairly controlled bronchial asthma. This antiasthmatic ability of ibudilast was restrained in those patients whose peripheral leukocytopenia was advanced before ibudilast administration, and in those whom ibudilast did not provoke an increase in the plasma level of iC3b, or did not prevent the serum level of C5 from increasing. In those unfairly controlled cases, enough anaphylatoxins, especially C5a might be produced to make the margination of peripheral neutrophils to the lung and increase CR3 on neutrophils binding with iC3b.

Adult↗
PubMed1991

[Treatment of iron overload with combination of recombinant human erythropoietin and phlebotomy].

A patient of Coombs negative autoimmune hemolytic anemia was massively transfused of 162 units concentrated red blood cells in 3 months and developed iron overload disease which was confirmed by liver biopsy. Hemolysis was successfully treated with high-dose methyl-prednisolone therapy and splenectomy. To treat iron overload, we administered recombinant human erythropoietin (Epo) in combination with phlebotomy. Total iron removed for 5 months was about 4 g. Thus, combination of Epo and phlebotomy was effective for the treatment of iron overload disease. Furthermore, we compared a degree of clinical effect of subcutaneous administration of Epo with that of intravenous administration in the clinical course and found the former more effective.

Adult↗
PubMed1990

Variation in the cholesterol/phospholipid ratio in human spermatozoa and its relationship with capacitation.

The cholesterol/phospholipid (C/PL) ratio was determined for spermatozoa from eight men with normal semen parameters. There was a close correlation between the C/PL ratio and the rate of sperm capacitation as assessed by the hamster egg penetration test. A lower C/PL ratio correlated with a faster capacitation time. This supports the notion that the loss or reduction of membrane cholesterol constitutes an important step of capacitation in human spermatozoa.

Adult↗
PubMed1990

Automated semen analysis shows an increase in sperm concentration and motility with time in Makler chambers having excess sample volume.

The sperm concentration and motility within a Makler chamber increased markedly after 3-5 min of settling when one large drop (approximately 24 microliters) of semen was loaded in the chamber. The values remained stable when a 5-microliter volume was loaded and were intermediate with a 10-microliter volume. In order to obtain accurate data, it is necessary to load the Makler chamber with a semen volume of no more than 5 microliters.

Automation↗
PubMed1990

[Immunoglobulin class and light chain type of oligoclonal bands in CSF in children with CNS infectious diseases].

Agarose gel electrophoresis and immunofixation of CSF and serum from 16 patients aged from 1 day to 13 years with CNS infectious diseases (5 with purulent meningitis, 5 with aseptic meningitis, 4 with acute encephalitis, 1 with subdural empyema and 1 with SSPE) revealed oligoclonal IgG bands in 10 cases. In 4 cases, a high CSF/serum albumin ratio was recognized without an increase of IgG-index, probably representing a systemic immune response. Neither IgA nor IgM bands were recognized. IgG light chain was examined in 7 cases and IgG kappa bands predominated in 6 cases. IgG lambda bands predominance presented in only one case. Free IgG kappa or lambda chain was not found. These results suggested that the measurement of not only IgG-index but oligoclonal bands may have a diagnostic usefulness to know about local production of immunoglobulins in CSF.

Adolescent↗
PubMed1990

[A simplified method for the assessment of C1 esterase inhibitor function].

From the result that the activated form of C1-s(C1-s) prolonged the kinetics of hemolysis via complement, this assay was applied to assess C1 esterase inhibitor (C1INH) function. In the kinetic assay, the complement hemolytic activity was evaluated by the time which required to cause 50% reduction of the initial turbidity of sensitized sheep erythrocytes, and was expressed as T1/2. (1) T1/2 of pooled normal human sera (p-NHS) showed dose-dependent prolongation by the addition of various amounts of C1-s. (2) Preincubation of various amounts of functionally pure C1INH with the constant amounts of C1-s inhibited dose-dependently the prolongation of T1/2 by C1-s. (3) The C1INH activity of NHS was 840 +/- 80 units/ml (n = 6) and that of the C1INH deficient serum was 80 units/ml, which were calculated from the standard curve established by the addition of various amounts of purified C1INH. This test requiring only C1-s and sensitized sheep erythrocytes is simple technically and high in sensitivity, and seems to be useful for the routine assay for C1INH function of human sera.

Animals↗
PubMed1990

[Plasma levels of complement fragments during hemodialysis in patients with chronic renal failure].

The kinetics of hemodialysis-induced leukopenia and generation of complement fragments including C3a, C5a, C4d, iC3b and Bb were investigated in 14 patients during hemodialysis using cellulose acetate (CA), cuprophan (Cu) and ethylenevinyl alcohol (EVA) membranes. A marked leukopenia in the first 15 minutes was observed in CA and Cu. Plasma C3a levels were higher in CA than in Cu and EVA. Plasma C5a levels were higher in CA and Cu than in EVA. There was a negative correlation between the white blood cell counts and plasma C5a levels at 15 minutes (gamma = -0.85, p less than 0.001). Plasma C4d levels showed no increase in all membranes. Plasma iC3b levels were higher significantly in Cu than in CA and EVA. Plasma Bb levels in the first 15 minutes increased significantly in all membranes, and furthermore continued to increase till the end of hemodialysis in CA and Cu. This study revealed that all the membranes tested activated the complement via the alternative pathway to produce Bb, iC3b, C3a and C5a. C5a was thought to take an important role in transient leukopenia. Furthermore, Bb was accumulated during hemodialysis in CA and Cu, and its biological effects on patients undergoing hemodialysis should be studied.

Adult↗
PubMed1989

[Changes of complement in immune complex glomerulonephritis induced by cationized antigen].

Complement system takes an important role in the pathogenesis of immune complex glomerulonephritis. In this study the precise changes of serum complement and its deposition in the glomeruli were investigated in the mice models induced with cationized bovine gamma-globulin (CBGG). Balb/c mice preimmunized with CBGG were injected intravenously with CBGG three times every 24 hours. Proteinuria and hypoalbuminemia have developed from day 3 until the death on day 9-13 of progressed azotemia. This nephritis resembled to mesangial proliferative glomerulonephritis histopathologically. Immunofluorescent study revealed granular deposits of CBGG, IgG, A, M and C3 along the glomerular capillary loop. Serum C3 decreased to about 50% of normal controls within 1 hour after challenge of antigen and plasma C3 conversion evaluated by crossed-immunoelectrophoresis, occurred in accordance with C3 reduction and then decreased. Immunofluorescent study showed a big difference in the mode of deposition among IgG, CBGG and C3. The most intense deposits of C3 in the glomeruli were seen 12 hours after challenge of CBGG, and then gradually decreased until the next challenge. IgG and CBGG antigen deposited most intensely soon after the challenge of antigen, and gradually decreased. These results led us to conclude that there existed two phases of complement activation in this immune complex induced mice glomerulonephritis; an early phase activation of complement by antigen-antibody complexes in the circulation and later phase activation of complement by immune complexes after deposition of them in situ glomeruli.

Animals↗
PubMed1989

[MRI findings in studies of distal myopathy with rimmed vacuoles].

A case of distal myopathy with rimmed vacuoles was studied with MRI, which showed a characteristic distribution of the affected muscles. A 41-year-old man who presented a slowly progressive weakness in his lower legs starting 11 years previously was admitted to our hospital of further investigation. Neurological examinations showed muscular wasting and weakness in the neck flexors, the flexors of the forearm, the flexors and adductors of the thigh and the extensors of the lower legs. Needle electromyography showed a myopathic pattern. Muscle biopsy revealed a variation in fiber size, an increase in internal nuclei, fatty infiltration and scattered rimmed vacuoles in a histochemical study. Electron microscopy revealed that rimmed vacuoles contained numerous lamellar bodies and glycogen particles. T1 and T2 weighted MRI showed high signals in the m. adductor of thigh m. biceps femoris, m. semimembranosus, m. semitendinosus, m. tibialis anterior, m. tibialis posterior, m. extensor digitorum longus, m. extensor digitorum brevis, m. peroneus, and m. gastrocnemius. There were three merits for the application of MRI to distal myopathy, (1) easy detection of the affected muscles as fatty change is expressed with a high signal intensity by MRI, (2) no affection by the presence of bones in MRI, and (3) the possibility to have a transverse section and a sagittal and coronal section in MRI. In this case MRI was very useful to detect the affected muscles and to observe the progress.

Adult↗
PubMed1988

Changes in the motility pattern of human spermatozoa during in vitro incubation.

Suspensions of capacitating human spermatozoa were analyzed for movement characteristics using high-speed videomicrography. The status of the acrosome reaction was also assessed by the zona-free hamster ova penetration test. (1) Movement characteristics of human spermatozoa were classified into 4 types (A, B, C, D). Type A: The movement was active, but its progressive orientation was irregular. Type B: The spermatozoa moved with a wide amplitude of the end of tail. Type C: The amplitude of the tail decreased, and the linear velocity of progression increased. Type D: The whole part of tail showed wavelike rhythmical movements, and the velocity more increased. (2) Movement characteristics of human spermatozoa in vitro gradually changed from Type A to B, C and D. As the spermatozoa classified Type D moved very powerfully and this motility pattern was obviously different from the other types, it was considered hyperactivation of human spermatozoa. The Type D was found from 2 or 3 hr of incubation, and after 3 or 4 hr most of the spermatozoa showed Type D. (3) The motility pattern of human spermatozoa changed to the Type D before the spermatozoa penetrate into zona-free hamster oocytes. It suggested that the hyperactivation occurred before the acrosome reaction takes place.

Animals↗
PubMed1985

[Ammonia in the intestinal contents from germfree rats].

The values of pH and the concentrations of nitrogen (N) and ammonia in the middle part of the small intestinal and cecal contents of germfree (GF) and conventionalized (CVZ) seven-week-old rats were compared. The pH of the small intestinal and cecal contents of GF rats was higher than that of CVZ rats. There was no difference in total N per fresh weight in contents from the middle part of the small intestine between GF and CVZ, whereas total N per fresh weight of the cecal contents was higher in CVZ than in GF rats. The ammonia concentrations per fresh weight or per total N in the intestinal and cecal contents of CVZ rats were higher than those of GF rats.

Ammonia↗