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S Tachikawa

Publications and source records attributed to S Tachikawa.

At least 37 records · Page 2Linked to original sources
PubMed1996

A frozen-thawed in vitro-matured bovine oocyte derived calf with normal growth and fertility.

The growth and fertility of a female calf obtained from a frozen-thawed bovine oocyte was assessed. The birth weight of the calf was lower than the mean birth weight of calves from in vitro fertilized embryos (IVF-controls) and calves obtained by artificial insemination (AI-controls). The growth rate of the calf up to 6 months was slower than that of the IVF-controls, but similar to that of the AI-controls. When the calf developed into a heifer (200 kg), she was inseminated with frozen semen and 280 days later delivered a male calf. The chromosoms of this cow were normal. These findings suggest that the growth and fertility of the calf derived from the frozen oocyte are normal.

Animals↗
PubMed1994

Developmental competence of bovine oocytes frozen at different cooling rates.

Experiments were conducted to determine the optimal cooling conditions for improving the developmental competence of in vitro-matured bovine oocytes when frozen in 1.6 M 1,2-propanediol. Bovine oocytes were cooled from 0 degree to -5.5 degrees C at 1 degree C/min, seeded, and then cooled to -30 degrees C at different cooling rates (0.3 degree, 0.6 degree or 0.9 degree C/min) and then plunged into LN2. When frozen-thawed oocytes were fertilized in vitro, the proportions of fertilization and developmental competence did not differ among the three groups frozen at different cooling rates. The findings indicated that a cooling rate of less than 1.0 degree C/min in the freezing procedure did not affect the developmental competence of postthaw in vitro-matured bovine oocytes.

Animals↗
PubMed1994

[Byssinosis].

Explore the source record for details and available documents.

Byssinosis↗
PubMed1993

Successful vitrification of bovine blastocysts, derived by in vitro maturation and fertilization.

Bovine blastocysts were produced through maturation, fertilization, and development in vitro. For vitrification, solutions designated EFS, GFS, and PFS were prepared; these were 40% ethylene glycol, 40% glycerol, and 40% propylene glycol, respectively, diluted in modified phosphate-buffered saline (PBS) containing 30% Ficoll + 0.5 M sucrose. The embryos were exposed to the solutions in one step at room temperature, kept in the solutions for various times, vitrified in liquid nitrogen, and warmed rapidly. When the embryos were vitrified in EFS solution after 1 or 2 min exposure, the postwarming survival rate, assessed by the reexpansion of the blastocoel, was 74-77%. However, when the exposure time was extended to 3 min or longer, this rate dropped to 7-0%. This reduction was attributed to the toxicity of ethylene glycol. Of the embryos vitrified in GFS solution, 53% survived when they were cooled after 1 min exposure; as the duration of the exposure increased, the survival rate increased, reaching a peak (72%) at 4 min. The rate then decreased gradually with exposure time. In PFS solution, embryos surviving after vitrification were recovered only with 1 min exposure (33%), reflecting the high toxicity of propylene glycol. After vitrification in EFS or GFS solution, two embryos were nonsurgically transferred into each of 14 recipient animals. Of the 14 recipients, ten (71%) became pregnant; two resulted in early stillbirths, four recipients delivered twins (four alive and four stillborn), and two delivered single live calves, demonstrating the effectiveness of this simple vitrification method for the cryopreservation of in-vitro-produced bovine blastocysts.

Animals↗
PubMed1993

Developmental capacity of bovine oocytes frozen in different cryoprotectants.

Iso-osmolar concentrations of 1.6 M of 1,2-propanediol, glycerol and dimethylsulfoxide were compared for their effectiveness as cryoprotectants for in vitro-matured bovine oocytes. Survival, defined as the number of morphologically normal oocytes, after freeze-thawing in 1,2-propanediol (49.8%) was significantly higher (P<0.01) than in glycerol (28.6%) or dimethylsulfoxide (32.6%). After insemination, the fertilization rate of morphologically normal oocytes frozen-thawed in 1,2-propanediol (57.9%) was higher (P<0.05) than that of those frozen in dimethylsulfoxide (38.3%). However, the proportion of surviving oocytes developing to blastocysts was not different among the 3 groups.

Journal Article↗
PubMed1993

Effects of different lots of semen from the same bull on in vitro development of bovine oocytes fertilized in vitro.

The effectiveness of 8 different lots of semen from the same bull on the in vitro development of bovine oocytes fertilized in vitro was evaluated. Cleavage and development rates to the blastocyst stage were not significantly different among the 8 lots of semen. However, the cleavage and development rates varied no more than +/-11 and +/-6%, respectively, in overall rates. A maximum of 35.2 and 27.9% difference in cleavage and development rates to the blastocyst stage, respectively, was observed using a single straw from the same semen lot for insemination in 4 trials. This variation tended to be higher than that observed for the cleavage and development rates of oocytes after insemination with double straws from a single lot. These results indicate that the developmental capacity of embryos after insemination are affected by factors associated with a different semen lot from the same bull and with different straws from a single lot.

Journal Article↗
PubMed1993

Small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features of the thoracic wall: a case report with histological, immunohistochemical and ultrastructural examinations.

A case of small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features is presented. The tumor was encountered in a 32 year old Japanese woman with an initial presentation of palpable tumor in the left lateral region of the thorax. The resected tumor was a partially well encapsulated whitish medullary one and consisted of small round and spindle tumor cells, together with so-called rhabdoid cells in the small round cell area. Although pseudorosettes were often observed, true rosette formation could not be detected anywhere. Ultrastructurally, despite a histologic variety of tumor cells, most tumor cells possessed numerous mitochondria, some of which occasionally contained abnormal filamentous or crystalloid structures. Various amounts of microfilaments were present in most tumor cells and microtubules were present in a few. A minority of small round cells possessed a small number of neurosecretory granules, especially in short cytoplasmic processes. A positive immunoreaction for neuron specific enolase was found by immunohistochemical examination in several small round tumor cells and for neurofilaments in lesser numbers. Despite the lack of S-100 protein, MB2 was detected in both small round and spindle cells. On the basis of these findings, the tumor of the present case corresponds to malignant peripheral nerve sheath tumor with neuronal differentiation and oncocytic features.

Adult↗
PubMed1993

Effect of washing, antibiotics and trypsin treatment of bovine embryos on the removal of adhering K99+ Escherichia coli.

Bovine embryos with the intact zona pellucida were exposed in vitro to K99+ Escherichia coli (K99 E. coli). The recommended procedures for washing and treating embryos were then evaluated for their effectiveness in removing or killing the adherent bacteria. After 10-step washing, bacteria were recovered not only from the embryos exposed to E. coli suspensions but also from those treated with trypsin during washing. On the other hand, no bacteria were recovered from any embryos treated with antibiotics (gentamicin; 50 micrograms/ml) in culture medium before washing, indicating that the recommended washing procedures with appropriate antibiotics assure that zona pellucida-intact bovine embryos are free from E. coli.

Animals↗
PubMed1993

Effect of trypsin treatment of in vitro fertilized bovine embryos on their subsequent survival and development.

The object of this study was to determine whether several washings with trypsin affected the survival and development of in vitro fertilized (IVF) bovine embryos. The embryos developed to blastocysts 7-8 days after insemination, were washed 12 times in washing medium (modified Dulbecco's phosphate-buffered saline (mPBS) containing 20% fetal bovine serum (FBS): 25 mM Hepes TCM199 with Earle's salts = 1:1), or in a series of three washes in the washing medium, two in mPBS containing 0.3% bovine serum albumin (BSA), two in 0.25% trypsin in Hank's solution (without Ca++ and Mg++) for a total time in the trypsin of 60 to 90 sec and five in the washing medium. After washing, the embryos were either cultured in vitro or cryopreserved. The fresh and frozen-thawed embryos were either cultured for 72 hr in vitro for evaluating development or transferred nonsurgically to recipient cows. Development of fresh and frozen-thawed embryos in vitro in control-washed and trypsin-washed embryos did not differ. Pregnancy rates did not differ (P > 0.05) among recipient cows receiving control-washed or trypsin-washed embryos, and transferring fresh or frozen-thawed embryos. These results indicate that the treatment of bovine IVF embryos with trypsin during washing did not have a positive effect on embryonic development.

Animals↗
PubMed1993

[Effects of sevoflurane on hemodynamics during the induction of anesthesia compared with those of isoflurane, enflurane and halothane].

The effects of sevoflurane (S), isoflurane (I), enflurane (E) and halothane (H) on hemodynamics were studied in 50 patients during the inhalation of 1.5 MAC of each anesthetic before the surgery. Mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI) and stroke volume index (SVI) were measured noninvasively using the automatic blood pressure manometer and the ultrasonic Doppler method (Accucom). There were significant differences between E and H in MAP, CI, SVRI and SVI. The values of CI, SVRI, SVI with S, as well as with I, were between those of E and H. These results indicate that sevoflurane causes the depression of blood pressure mostly by decreasing afterload during the induction of anesthesia, although the decrement with sevoflurane, as well as that with isoflurane, is less than that with enflurane.

Adult↗
PubMed1992

Microcytic variant of thymoma: histological and immunohistochemical findings in two cases.

Two cases of microcytic variant of thymoma are presented. Both tumours were well encapsulated with a yellow-whitish colour and soft consistency. Microscopically, they consisted of round cells, having ample vacuolated cytoplasm. Fat droplets were not detected in one case where fat staining was performed. Immunohistochemically, the tumour cells were strongly positive for AE1/AE3, MB1, MB2, and LN1 and faintly positive for epithelial membrane antigen. They lacked any other leucocyte antigens. Leu 7 showed a positive immunoreaction in a ring-like or homogeneous pattern, compatible with the cytoplasmic vacuoles or cytoplasm. Ultrastructurally, the vacuoles resembled cystically dilated rough-surfaced endoplasmic reticulum. Desmosome-like structures (case 1) and intermediate junctions (case 2) were identified between adjacent cells. These findings indicate that the present tumours belong to a category of microcystic thymoma. The vacuoles were attributed to excess accumulation of Leu-7-positive material, probably in the cystically dilated endoplasmic reticulum.

Antigens, Differentiation↗
PubMed1992

Developmental capacity of bovine oocytes cryopreserved after maturation in vitro and of frozen-thawed bovine embryos derived from frozen mature oocytes.

The present study was conducted 1) to investigate the post-thaw developmental capacity of in vitro mature bovine oocytes (Metaphase II) frozen by 1.6 M of 1,2-propanediol and 2) to confirm the viability of frozen bovine embryos derived from frozen mature oocytes. The cleavage and developmental rates to the blastocyst stage of frozen-thawed mature oocytes were significantly lower (P<0.01) than that of nonfrozen oocytes. When mature oocytes were treated with hyaluronidase, trypsin, or base solution (solution control) before processing to remove the cumulus cells, the developmental rates to the blastocyst stage of frozen-thawed oocytes were 2.8% (5/180), 3.1% (9/295) and 1.1% (1/89), respectively. The viability and developmental capacity of frozen-thawed bovine embryos derived from frozen mature oocytes were not different from those of frozen-thawed bovine embryos derived from nonfrozen mature oocytes (control). Furthermore, nonfrozen and frozen-thawed embryos derived from frozen-thawed mature oocytes were nonsurgically transferred to recipient cows. One of the four and one of the two recipient cows became pregnant, respectively. The results of this study demonstrated the viability of embryos obtained from frozen-thawed bovine oocytes at Metaphase II followed by in vitro fertilization and culture to the blastocyst stage in vitro.

Journal Article↗
PubMed1992

A case of pulmonary adenocarcinoma with sarcomatous elements initially manifested as a submucosal tumor of the stomach.

A case of pulmonary adenocarcinoma, which was initially manifested as a gastric submucosal tumor, is presented. Endoscopy showed a submucosal tumor in the fundic region in a 79-year-old Japanese woman. Initial biopsy specimens of the stomach revealed atypical spindle cell proliferation, suggesting primary leiomyosarcoma of the stomach. However, biopsy specimens obtained one year later were diagnosed as malignant lymphoma or malignant histiocytosis of the stomach. Autopsy revealed a large necrotic lesion in the right S8 region with metastases in multiple organs. Microscopy demonstrated well to moderately differentiated adenocarcinoma containing spindle or pleomorphic sarcomatous elements. Metastatic nodules including the gastric tumors all showed sarcomatous elements with no epithelial component. Immunohistochemistry showed positive reactions for keratin, epithelial membrane antigen, and carcinoembryonic antigen in areas of carcinoma, whereas most of the sarcomatous elements revealed no positivity for any of the antibodies used, except for focal keratin and EMA positivity in the primary site. This is a rare case of pulmonary adenocarcinoma with sarcomatous elements discovered as a gastric tumor at initial diagnosis, resulting from metastasis of the sarcomatous element in the submucosa.

Adenocarcinoma↗
PubMed1992

Clear cell hepatocellular carcinoma with abundant myxoid stroma.

A case of the clear cell variant of hepatocellular carcinoma with an abundant myxoid stroma is presented. The tumor occurred in a 55-year-old Japanese man, and swelling of the scrotum was the initial symptom. The patient underwent high-level orchiectomy, and the pathologic diagnosis was a metastatic tumor on the surface of the processus vaginalis and intact testis. Extensive examination failed to show a primary site. Subsequent autopsy revealed a large hepatic tumor and metastatic nodules with a prominent myxoid appearance in multiple organs. Histologically, each tumor consisted of uniform small tumor cells with clear cytoplasm attributed to abundant accumulation of glycogen particles, and an abundant myxoid stroma was also present. The tumor cells were positive for keratin, alpha 1-antitrypsin, alpha 1-antichymotrypsin, liver ferritin, prealbumin, and fibrinogen, but lacked alpha-fetoprotein. These findings indicated that this case was hepatocellular carcinoma of the clear cell type with a prominent myxoid stroma.

Antibodies, Monoclonal↗
PubMed1992

[Prophylactic effect of ulinastatin on cisplatin-induced renal disorders in lung cancer patients].

In order to determine whether ulinastatin (US) can prevent renal dysfunction due to cisplatin (CDDP) or not, we comparatively studied serum BUN, serum creatinine (Cr), creatinine clearance (Ccr), urine gamma-glutamyl transpeptidase (gamma-GTP) excretion, urine N-acetyl-beta-D-glucosaminidase (NAG) excretion, fractional excretion of Na (FENa) and urine beta 2-microglobulin excretion between one group of 10 patients receiving single treatment with CDDP and another group of 10 patients receiving combination treatment with CDDP+US, in 20 subjects with primary lung cancer. In the US combination treatment group, urine gamma-GTP excretion, urine NAG excretion, and FENa elevation were significantly inhibited. Urine beta 2-microglobulin excretion was inhibited. In summary, US was considered to have a preventive effect against renal toxicity due to CDDP.

Aged↗
PubMed1991

Transitional cell carcinoma with sarcomatous elements in the urinary tract. Six cases examined by immunohistochemistry.

We report six cases of carcinoma showing sarcomatous change in the urinary tract examined by conventional histochemistry and immunohistochemistry. All of the cases were transitional cell carcinoma with or without focal squamous cell carcinoma. Sarcomatous components resembling spindle cell sarcoma with a marked myxoid stroma or chondrosarcomatous element were also observed in all cases. The sarcomatous elements were closely associated with the areas of squamous cell carcinoma in three cases. Various histochemical staining procedures demonstrated mesenchymal features in the stroma of sarcomatous areas. By immunohistochemical examination, the epithelial components showed positive reactions for keratin, epithelial membrane antigen and, focally, carcinoembryonic antigen. The sarcomatous components revealed a positive immunoreaction for keratin but lacked other epithelial markers in all cases. Chondrosarcomatous elements in two cases were positive for both keratin and S-100 protein. These findings indicate that sarcomatous elements in carcinoma may represent mesenchymal metaplasia with partial or complete loss of epithelial features. However, further study will be necessary in order to determine whether heterogeneous elements, such as chondrosarcomatous areas, are epithelial or truly mesenchymal in origin.

Aged↗
PubMed1991

[An MRI and SPECT study of frozen gait without other manifestations of parkinsonism in the elderly].

The authors have sometimes experienced cases of frozen gait without any other manifestations of parkinsonisms in the elderly, so we examined these cases using MR imaging and SPECT imaging. The group with frozen gait (4 cases, aged 78 to 82 years) which failed to respond to L-dopa therapy, had no limb-kinetic apraxia or frontal signs, but did exhibit "kinésie paradoxale". The clinical symptoms of case 4 were consistent with so-called "pure akinesia". CT findings in this group failed to elucidate the pathogenesis of frozen gait. MR imaging of all of the cases except for the case of pure akinesia (case 4) revealed a high signal intensity areas in subcortical lesions (especially the frontal area). Case 4 had only a few spotty high-signal intensity areas. We then compared 6 cases which have the same lesions (on MRI) as cases 1-3 without frozen gait in cases 1-3 using 123I-IMP SPECT. Relatively low accumulation of radionuclide in the frontal area was observed in these cases. Case 4 had a slightly low perfusion area in the frontal lobe. However in the patient treated with L-threo-DOPS, accumulation of radionuclide in the frontal area increased slightly after L-threo-DOPS therapy. It appears that one of the reasons for frozen gait in the elderly is incomplete infarct of the subcortical white matter with a low perfusion area in the frontal cortex. Furthermore, in some cases of frozen gait it is difficult to distinguish between cases with white matter disorders and cases of pure akinesia on the basis of clinical symptoms and CT alone.

Amphetamines↗