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K Yanagida

Publications and source records attributed to K Yanagida.

At least 37 records · Page 2Linked to original sources
PubMed1999

The usefulness of a piezo-micromanipulator in intracytoplasmic sperm injection in humans.

Intracytoplasmic sperm injection (ICSI) has wide clinical application. In order to achieve good results with this method, it is important to restrict the possibility of oocyte injury as much as possible, and securely inject spermatozoa into the ooplasm. For this purpose, we clinically applied piezo-ICSI, which employs a micromanipulator with piezoelectric elements, to humans, and compared the results with those obtained by conventional ICSI. Conventional ICSI and piezo-ICSI were used in 279 cycles and 335 cycles respectively. Piezo-ICSI showed significantly more favourable results, with a survival rate of 88.1% (conventional ICSI: 81.4, P < 0.001), a fertilization rate of 79.4% (conventional ICSI: 66.4%, P < 0.001), and a pregnancy rate of 23.1% (conventional ICSI: 14.9%, P < 0.05). In piezo-ICSI, the needle used is not sharpened and has a flat tip. However, deformation of the oocyte during insertion of the needle is restrained by vibration of the piezo, and the oolemma is punctured readily and securely by the piezo pulse, at the site where the spermatozoon is injected. Piezo-ICSI is a promising new technique for human ICSI that should improve the survival, fertilization and pregnancy rates after ICSI.

Adult↗
PubMed1999

Successful fertilization and pregnancy following ICSI and electrical oocyte activation.

In a total of 1048 intracytoplasmic sperm injection (ICSI) cycles, motile spermatozoa from four out of 424 patients (0.9%) failed to fertilize oocytes, despite an apparently successful ICSI procedure. No activation was observed in these injected oocytes. The spermatozoa from three of the four patients were injected into unfertilized mouse oocytes by ICSI (mouse test) to evaluate their oocyte activating ability. The oocyte activation rate of the spermatozoa of patients A, B, and C in the mouse test was 46, 100, and 86% respectively (control: 100%). Simultaneous injection of two spermatozoa from patient A into the mouse oocytes increased the oocyte activating rate to 89% (sham control: 29%). 100% fertilization rates were obtained for patients A and B by combining ICSI and electrical stimulation, and this resulted in pregnancy and the birth of healthy twins for the partner of patient A. Thus, it is considered that the spermatozoa of these patients are not lacking sperm factors but that the activity of these factors is depressed. The combination of ICSI and electrical stimulation is effective in these cases.

Animals↗
PubMed1999

Prenatal diagnosis of intrapericardial teratoma: a case report.

A hydropic fetus that exhibited intrapericardial teratoma with marked pericardial effusion was prenatally diagnosed. Intrauterine pericardiocentesis was performed to diagnose and to treat hydrops. Pericardiocentesis for tamponade secondary to a fetal intrapericardial teratoma might prevent fetal death and premature delivery.

Adult↗
PubMed1999

Risk of recurrence of fetal chromosomal aberrations: analysis of trisomy 21, trisomy 18, trisomy 13, and 45,X in 1,076 Japanese mothers.

OBJECTIVE: To evaluate the risk of recurrence of fetal chromosomal aberrations in women who had offspring with numeric chromosomal abnormalities. SUBJECTS AND METHODS: This collaborative study consisted of 1,076 Japanese women with a history of offspring with trisomy-21, -18, -13, or 45,X. Second-trimester amniocenteses were performed, resulting in 1,248 fetal karyotypes that were analyzed with reference to prior offspring karyotypes and maternal age. RESULTS: Of the 842 women with trisomy-21 offspring, 10 conceived another such fetus. In 2 women with 3 or more such offspring, parental mosaicism of trisomy-21 was suspected. The incidence of recurrence of trisomy-21 increased with age, and significantly exceeded the incidence of trisomy-21 fetuses in the general population. None of the 170 women with trisomy-18 offspring, and none of the 46 women with trisomy-13 offspring, had another such fetus. Of the 18 women with 45,X offspring, 1 with mos 45,X/46,XX had another such fetus. CONCLUSIONS: The risk of recurrence of trisomy-21 is affected by maternal age and parental germline mosaicism. The risk of recurrence of trisomy-18 or -13 appears to be much lower than that of trisomy-21. Women who give birth to more than 1 offspring with 45,X should be examined for mos 45,X/46,XX.

Adult↗
PubMed1999

Re-assessment of stage I uterine cervical carcinoma according to revised JSGO (1997) staging.

BACKGROUND: The Japanese Society of Gynecologist and Obstetrician (JSGO) revised criteria for early uterine cervical cancer. OBJECTIVE: In this study, we investigated the value of the revised JSGO criteria. METHOD: Retrospective review was performed for 70 patients with tumors limited to the uterine cervix who were classified stage I under old JSGO criteria. RESULT: Forty patients were re-classified into stage IA1 and 4 patients into stage IA2. Incidence of lymph-vascular infiltration (LVI) in stage IA1 and IA2 were 5% and 25%. There was one patient with stage IA1 disease who had nodal metastasis and no patients with stage IA2 disease. There were 14 patients with stage IB1 disease and 12 patients with stage IB2 disease. Mortality of patients with stage IB2 disease was 25% and significantly higher than that of patients with stage IA and IB1 disease (P<0.001 and <0.05) CONCLUSION: Although the revised JSGO criteria for early cervical cancer are acceptable for assessment of patients, the therapy of patients is still controversial. We recommend that patients with stage IA1 and negative LVI should have less radical hysterectomy and patients with stage IA1 with LVI or stage IA2, IB should have radical hysterectomy.

Adult↗
PubMed1998

New method of Helmholtz coil alignment.

A new alignment method for Helmholtz coils is proposed. This method is based on a probe, whose axis is the same as the alignment axis. This probe includes one magnetic sensor, whose position is slightly shifted from the probe axis, and which is set perpendicular to the axis. Using this probe, the tilt and shift of the magnetic centre of Helmholtz coils can be aligned to within an order of 0.1 mrad and 0.1 mm, respectively. Moreover, by this method, effects of terrestrial magnetism and tilt of the magnetic sensor can be removed from the measurement. This alignment method is presented along with an estimate of the alignment accuracy of the SPring-8 linac injector.

Journal Article↗
PubMed1998

Introduction of a new scale into reversed-phase high-performance liquid chromatography of pyridylamino sugar chains for structural assignment.

Addition of a monosaccharide residue to a pyridylaminated (PA)-N-linked sugar chain results in an increment or decrement in the elution time on reversed-phase HPLC, the difference being defined as the partial elution time of the residue. Based on this principle, an empirical rule was deduced, which states that the elution time is roughly equal to the sum of the partial elution times of the component sugar residues [Anal. Biochem., 167 (1987) 321-326]. In practice, however, some partial elution times obtained from different pairs of mother PA-sugar chains are found to deviate, and consequently the closeness of the elution times of PA-sugar chains calculated therefrom to the observed times is reduced in such cases. To improve the reliability of the additivity rule and to generalize elution times so that they are less dependent on minor alterations in the elution conditions, we have devised a new scale for elution time, which we have named a reversed-phase scale. The elution times on the reversed-phase scale (the R values) are read from a conversion curve constructed using the elution times of eight selected standard PA-sugar chains. The partial elution times on the reversed-phase scale of 22 monosaccharide residues were calculated from the R values of 93 PA-sugar chains. The R values obtained by summing the partial elution times of all the component monosaccharide residues became much closer to the R values obtained from the reversed-phase scale, compared to the results obtained using the previous method. In addition, the R values were less influenced by minor change in the elution conditions. These features of the new scale allow more accurate structural assignment of sugar chains.

Amino Sugars↗
PubMed1998

Dysgerminoma with syncytiotrophoblastic giant cells arising from 46,XX pure gonadal dysgenesis.

BACKGROUND: Dysgerminoma with syncytiotrophblastic giant cells is a rare ovarian tumor. Only ten cases of this tumor have been reported, and all tumors developed in normal ovaries. This report presents a case of dysgerminoma with syncytiotrophoblastic giant cells arising in a patient with 46,XX pure gonadal dysgenesis. CASE: An 18-year-old phenotypic female of normal height without somatic anomalies with nonfunctional ovaries underwent a bilateral gonadectomy for a right ovarian tumor and left streak gonad. The tumor revealed a dysgerminoma containing scattered syncytiotrophoblastic giant cells. Her serum hCG was elevated, and hCG was demonstrated within syncytiotrophoblastic giant cells immunohistochemically. The clinical diagnosis was stage Ia dysgerminoma with syncytiotrophoblastic giant cells. Her karyotype was 46,XX and the sex-determining region Y gene was not detected in tumor DNA by polymerase chain reaction analysis. CONCLUSION: This rare gonadal tumor may arise from dysgenetic gonads in addition to gonadoblastoma and pure dysgerminoma. It is an example of tumorgenesis in pure gonadal dysgenesis with no identifiable Y chromosome component.

Adolescent↗
PubMed1998

Comparison of the media for isolation and storage of round spermatid nuclei before intracytoplasmic injection.

PURPOSE: This study investigated whether K(+)-rich medium is better than pure NaCl solution or Na(+)-rich cell culture medium for handling round spermatid nuclei prior to injection into oocytes (ROSNI). METHODS: Round spermatids of the mouse were isolated and stored in isotonic NaCl, a cell culture medium (CZB), or a nucleus isolation medium (NIM) before injection into oocytes. The rates of normal fertilization, embryonic development in vitro, and birth of normal offspring after transfer of embryos to foster mothers were determined. RESULTS: In vitro development of ROSNI-produced zygotes to blastocysts was the same when "naked" spermatid nuclei were exposed briefly to three media. However, a long (60-min) exposure of the nuclei to Na(+)-rich medium was detrimental. In K(+)-rich NIM "naked" spermatid nuclei best retained their ability to participate in normal embryonic development. CONCLUSION: NIM was better than Na(+)-rich medium for retaining isolated spermatids competent to participate in normal embryonic development.

Animals↗
PubMed1998

Influence of oocyte preincubation time on fertilization after intracytoplasmic sperm injection.

During the intracytoplasmic sperm injection (ICSI) procedure, the collected oocytes are incubated until just before ICSI. The ideal preincubation time of oocytes was investigated in 544 treatment cycles. Oocyte retrieval was carried out 35 h after human chorionic gonadotrophin administration. Oocytes were cultured for between 1 and 11 h before ICSI. Embryo transfer was performed 48 h after oocyte collection. The survival, fertilization and cleavage rates of injected oocytes indicated no statistically significant differences between oocytes preincubated for different lengths of time. The proportion of good-quality embryos (grades 1 and 2) was lower at 9-11 h of preincubation time than for all the other preincubation times (P < 0.001). No statistically significant differences were detected in the pregnancy rate between each group (mean: 15.9%), although the pregnancy rate at 9-11 h of preincubation time appeared to be low (7.7%). These results suggest that the oocyte retained sufficient potential for fertilization between 1 and 9 h after oocyte collection in ICSI. For the researchers who practise more complex ICSI procedures than IVF, it would be convenient to be able to perform ICSI at any time between 1 and 9 h after oocyte collection.

Adult↗
PubMed1998

Evaluation of immunostaining for MIB1 and nm23 products in uterine cervical adenocarcinoma.

In this study, we evaluated whether proliferative activity and metastatic potential are prognostic factors in adenocarcinoma of the cervix. Formalin-fixed, paraffin-embedded sections from 34 patients with cervical adenocarcinoma or adenosquamous carcinoma were immunostained with monoclonal antibody MIB1, expressed in proliferating cells, and anti-nm23 antibody, reacts with metastasis suppression gene products. MIB1 positivity ranged from 0.2 approximately 54.7% with a mean of 21.4%. The level did not differ significantly between various clinicopathological categories. Although patient survival of high or low MIB1 expressing tumor was not significantly different, the disease-free interval of high (> or =25%) expressing tumor was significantly lower than that of low (<25%) expressing tumor. Strong and medium expression for nm23 were detected in 7 (21%) and 3 (9%) of patients. Tumor with strong nm23 expression tended to have a higher relapse rate. Although the survival of strong and weakly nm23 expressing tumor was not significantly different, the disease-free survival of strong nm23 expressing tumor was lower than that of weakly nm23 expressing tumor. MIB1 and nm23 immunostaining might be some of prognostic indicators of recurrence in cervical adenocarcinoma. In cervical adenocarcinoma, the nm23 gene products may not function as metastatic suppression but reflect proliferative activity.

Adenocarcinoma↗
PubMed1998

[A case of systemic lupus erythematosus complicated with marked intestinal edema and paralytic ileus].

A 43-years-old female was admitted to our hospital because of facial erythema and photosensitivity in 1983 and was diagnosed as systemic lupus erythematosus (SLE). She was treated with betamethazone 2.5 mg/day as an outpatient. Abdominal pain and diarrhea were developed in September, 1995. So she was admitted to our hospital and diagnosed as having paralytic ileus. Ultrasonography showed marked intestinal edema. Forbidden oral intake and given antibiotics, she was satisfactorily improved in a few days, but the symptoms got worse soon. We forbid oral intake again. We performed a pulse therapy with 1 g of methylprednisolone and increased a dose of betamethasone 2.5 to 4.0 mg/day, but the symptoms were not improved. Since October 6th, serum creatinine level (s-CRE) increased to 8.1 mg/dl at October, 20th. We suspected the worsening of SLE nephropathy or drug-induced nephropathy, so we stopped a medication of pravastatin and used 50 mg/day of azathioprine. Moreover, we did a pulse therapy of methylprednisolone and a plasmapheresis. By these treatments, s-CRE level returned to normal range and paralytic ileus was completely improved. The cause of hypercreatininemia was suspected to be rhabdomyolysis due to pravastatin. The main cause of paralytic ileus with intestinal edema was suspected to be vascular disturbance of superior mesenteric arteries. We consider that pulse therapy and plasmapheresis are useful for a patient of SLE with marked intestinal edema and paralytic ileus.

Adult↗
PubMed1997

Pituitary adenylate cyclase-activating polypeptide (PACAP) is an islet substance serving as an intra-islet amplifier of glucose-induced insulin secretion in rats.

1. We examined whether pituitary adenylate cyclase-activating polypeptide with 38 or 27 residues (PACAP-38 or PACAP-27) serves as an intra-islet regulator of glucose-induced insulin secretion in rats. PACAP antiserum specific for PACAP-38 and PACAP-27 was used to neutralize the effect of endogenous PACAP in islets. PACAP release from islets was bioassayed using the response of cytosolic Ca2+ concentration ([Ca2+]i) in single beta-cells, monitored by dual-wavelength fura-2 microfluorometry. Expression of PACAP mRNA was studied by reverse transcription-polymerase chain reaction (RT-PCR), while expression of PACAP was studied by metabolic labelling and immunoblotting. Localization of PACAP receptors was studied immunohistochemically. 2. High glucose-stimulated insulin release from isolated islets was attenuated by PACAP antiserum but not by non-immune sera. 3. The islet incubation medium with high glucose (Med) possessed a capacity, which was neutralized by PACAP antiserum, to increase [Ca2+]i in beta-cells. PACAP antiserum also neutralized the [Ca2+]i-increasing action of synthetic PACAP-38 and PACAP-27, but not that of vasoactive intestinal polypeptide (VIP) and glucagon. 4. Both Med and synthetic PACAP increased [Ca2+]i in beta-cells only in the presence of stimulatory, but not basal, glucose concentrations. In contrast, ATP, a substance that is known to be released from beta-cells, increased [Ca2+]i in beta-cells at both and stimulatory glucose concentrations. 5. Expression of PACAP mRNA and biosynthesis of PACAP-38 were detected in islets and a beta-cell line, MIN6. 6. Immunoreactivity for PACAP-selective type-I receptor was observed in islets. 7. [Ca2+]i measurements combined with immunocytochemistry with insulin antiserum revealed a substantial population of glucose-unresponsive beta-cells, many of which were recruited by PACAP-38 into [Ca2+]i responses. 8. These results indicate that PACAP-38 is a novel islet substance that is synthesized and released by islet cells and then, in an autocrine and/or paracrine manner, potentiates and arouses beta-cell responses to glucose, thereby amplifying glucose-induced insulin secretion in islets.

Adenosine Triphosphate↗
PubMed1997

[Small increase of CR1 and CR3 by C5a-receptors on polymorphonuclear leukocytes in systemic lupus erythematosus].

One of the anaphylatoxins, C5a, is known to increase the expression of the complement receptors, CR1 and CR3, on PMNs which play important roles in the phagocytosis. We measured the expression of these receptors before and after the stimulation with C5a and C5a-receptors (C5aR) on PMNs in patients with systemic lupus erythematosus (SLE). PMNs from 16 patients and 11 normal controls were tested. All the patients with SLE were administered with prednisolone orally and were in the inactive stage. The CR1 expression in SLE was significantly weak (p < 0.01) before and after stimulation with 4.55 nM (50 micrograms/ml) of C5a. There was no significant difference of CR3 expression before stimulation. However, after the stimulation with C5a, the increase of CR3 on PMNs from SLE was significantly small (p < 0.01). C5aR on PMNs showed no difference between the two groups. However, the expression of C5aR was significantly suppressed in patients treated with a high dosage of prednisolone (> = 10 mg/day) compared to those with a low dosage of prednisolone (< 10 mg/day). There was no significant difference of CR1 and CR3 expression between these groups. It is concluded that the increase of CR1 and CR3 on PMNs by C5a in small in SLE, of which impaired increase is not due to C5aR on PMNs, and that the expression of C5aR is suppressed by prednisolone.

Antigens, CD↗
PubMed1997

Fertilization using male germ line-cells.

In recent years, favorable results have been achieved in patients suffering from azoospermia by microinsemination of spermatozoa taken from their testes. Microinsemination is being introduced in the treatment of patients who have no spermatozoa in their testes via their spermatid and spermatocyte. There are still doubts relating to immature male germ line-cells, such as whether they have, oocyte activating factors, the level of stability of DNA of cell nuclei, and the differences in chromosome numbers. The relatively few cases of gestation using the human spermatid treatment may be due to embryological problems resulting from the instability of nuclear DNA and the insufficiency of oocyte activating factors, which are the result of imperfect microinjection techniques. Improvements in techniques for the clinical application of spermatid and secondary spermatocyte, as well as the collection of basic data to confirm embryological safety are therefore necessary.

Animals↗
PubMed1996

The relationship between acridine orange fluorescence of sperm nuclei and the fertilizing ability of human sperm.

OBJECTIVE: To determine whether the outcome of IVF can be predicted by acridine orange (AO) nuclear fluorescence of sperm. DESIGN: Based on the fact that AO nuclear fluorescence color after acid treatment reflects maturity (green fluorescence) or immaturity (yellow to red fluorescence) of spermatozoa, the relationships between sperm maturity and the outcome of IVF, subzonal insemination, or intracytoplasmic sperm injection (ICSI) were investigated. SETTING: The IVF program at the Obstetrics and Gynecology Hospital, Fukushima Medical College. PATIENTS: Sixty-eight patients undergoing 68 IVF treatment cycles. MAIN OUTCOME MEASURES: Acridine orange fluorescence of sperm nuclei and successful oocyte fertilization. RESULTS: conventional semen parameters (sperm concentration and percentages of motile or morphologically normal spermatozoa in semen) did not correlate with the incidence of spermatozoa with green AO fluorescent (mature) nuclei. When > or = 50% of spermatozoa in semen samples exhibited green AO nuclear fluorescence, IVF was always successful. When green AO nuclear fluorescence was < 50%, only 39% of IVF treatment cycles (13/33) were successful. Only green AO fluorescent spermatozoa were able to bind efficiently human zona pellucida. When the incidence of green AO fluorescent spermatozoa was < 50%, no pregnancy resulted even though an average of 26% of the oocytes could be fertilized by ICSI. CONCLUSIONS: The spermatozoa which fertilized oocytes in vivo and in IVF were limited to those whose nuclei exhibited green AO fluorescence. Intracytoplasmic sperm injection may be the method of choice when the incidence of green AO nuclear fluorescence is low regardless of the results of semen analysis.

Acridine Orange↗
PubMed1996

Radiographical evaluation of bone maturation in Japanese black beef cattle.

Epiphyseal ossification in the radius, ulna, metacarpus, proximal phalanx and tuber calcaneus was examined radiographically in Japanese Black beef cattle. The grade of standard ossification was assessed monthly for each epiphysis. Bone maturations could be divided into 8 grades for the distal radius and distal ulna, 7 grades for the distal metacarpus, 5 grades for the proximal phalanx, and 8 grades for the tuber calcaneus, respectively. The closure of the epiphyseal line completed at the earliest (12-14 months of age) on the proximal phalanx, and at the latest (35-37 months of age) on the distal ulna. Changes in gradings were steep at 0 to 5 months of age but became almost constant after 10 months of age in all the epiphyses. There were no significant differences in bone maturation between the cattle with different sex and breeding conditions.

Aging↗