著者
Risako KAWATA Tatsuhito II Tatsuya HORI Yukino MACHIDA Kazuhiko OCHIAI Daigo AZAKAMI Toshiyuki ISHIWATA Masaki MICHISHITA
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.81, no.2, pp.186-189, 2019 (Released:2019-02-09)
参考文献数
17
被引用文献数
1

A 14-year and 8-month-old intact male Amur tiger presented with an enlarged left testis, measuring 5.7 × 5.5 × 4.5 cm. The cut surface was mottled dark red to reddish brown in color. Microscopically, the enlarged left testis comprised round or polygonal neoplastic cells arranged in a diffuse sheet pattern. These neoplastic cells had a hyperchromatic nucleus and an abundant eosinophilic cytoplasm. Immunohistochemically, these neoplastic cells were positive for vimentin, chromogranin A, synaptophysin, melan-A, inhibin-α, and S100 and negative for desmin and WT-1. Based on these morphological and immunohistochemical findings, the tumor was diagnosed as a Leydig cell tumor.
著者
Masanori KOBAYASHI Akiko SAITO Yoshikazu TANAKA Masaki MICHISHITA Masato KOBAYASHI Mami IRIMAJIRI Takeharu KANEDA Kazuhiko OCHIAI Makoto BONKOBARA Kimimasa TAKAHASHI Tatsuya HORI Eiichi KAWAKAMI
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.79, no.4, pp.719-725, 2017 (Released:2017-04-05)
参考文献数
32
被引用文献数
23

Canine prostate cancer (cPCa) is an untreatable malignant neoplasm resulting in local tissue invasion and distant metastasis. MicroRNAs (miRs) are small non-coding RNAs that function as oncogenes or tumor suppressors. The purpose of this study was to characterize the expression of miRs that are altered in cPCa tissue. The expression levels of 277 mature miRs in prostatic tissue (n=5, respectively) were compared between the non-tumor and tumor groups using real-time PCR. Five miRs (miR-18a, 95, 221, 222 and 330) were up-regulated, but 14 miRs (miR-127, 148a, 205, 299, 329b, 335, 376a, 376c, 379, 380, 381, 411, 487b and 495) were down-regulated specifically in cPCa (P<0.05). These miRs have potential use as early diagnosis markers for cPCa and in miR-based therapy.
著者
Masanori KOBAYASHI Akiko SAITO Yoshikazu TANAKA Masaki MICHISHITA Masato KOBAYASHI Mami IRIMAJIRI Takeharu KANEDA Kazuhiko OCHIAI Makoto BONKOBARA Kimimasa TAKAHASHI Tatsuya HORI Eiichi KAWAKAMI
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.16-0279, (Released:2017-02-27)
被引用文献数
23

Canine prostate cancer (cPCa) is an untreatable malignant neoplasm resulting in local tissue invasion and distant metastasis. MicroRNAs (miRs) are small non-coding RNAs that function as oncogenes or tumor suppressors. The purpose of this study was to characterize the expression of miRs that are altered in cPCa tissue. The expression levels of 277 mature miRs in prostatic tissue (n=5, respectively) were compared between the non-tumor and tumor groups using real-time PCR. Five miRs (miR-18a, 95, 221, 222 and 330) were up-regulated, but 14 miRs (miR-127, 148a, 205, 299, 329b, 335, 376a, 376c, 379, 380, 381, 411, 487b and 495) were down-regulated specifically in cPCa (P<0.05). These miRs have potential use as early diagnosis markers for cPCa and in miR-based therapy.
著者
Toshihiko TSUTSUI Tatsuya HORI Hisako OKAZAKI Ayuko TANAKA Masataka SHIONO Makoto YOKOSUKA Eiichi KAWAKAMI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.63, no.4, pp.401-405, 2001 (Released:2001-05-10)
参考文献数
7
被引用文献数
25 29

In dogs, embryo transfer (ET) techniques such as induciton of excessive ovulation and synchronization of estrus have not progressed well. Therefore, using embryos at various developmental stages, ET was investigated in dogs from a beagle colony in which the ovulation days were close, as estimated by the progesterone level. Embryos were recovered 8-11 days after ovulation (4-9 days after mating) by excising the oviducts and uteri (excision method) in 16 animals and by surgical flushing of the uteri at laparotomy (surgical method) in 3 animals. In 24 dogs with -4 to +2 days of difference in the timing of ovulation between donor and recipient dogs, 1-10 embryos at the 8-cell to blastocyst stages were transferred per animal. The mean embryo recovery rate by the excision method (97.1%) was significantly higher than that by the surgical method (42.5%) (p<0.01). Twelve (57.1%) of 21 animals with -1 to +2 days difference in ovulation day became pregnant after the transfer of 8-cell to blastocyst stage embryos. Although 3 dogs with -4 to -2 days of difference of ovulation day underwent ET of morula or compacted morula, none of these dogs became pregnant. The mean ratio of the number of newborns to the number of transferred embryos was only 51.9%. The mean duration of the period between ovulation and delivery in the pregnant recipients was 65.8 days, which tended to be longer than that in natural mating. These results demonstrate that pregnancy can be induced by ET at the 8-cell to blastocyst stage in dogs with -1 to +2 days difference in ovulation day.
著者
Tatsuya HORI Hitoshi USHIJIMA Taku KIMURA Masanori KOBAYASHI Eiichi KAWAKAMI Toshihiko TSUTSUI
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.16-0037, (Released:2016-04-03)
被引用文献数
5

Canine embryos (8-cell to blastocyst stages) frozen–thawed using the slow-freezing method with glycerol (four recipients) or dimethyl sulfoxide (three recipients) as a cryoprotectant and vitrified–warmed using the Cryotop method (five recipients) were surgically transferred into the unilateral uterine horn of recipient bitches. As a result, the morphology of embryos frozen–thawed using the slow-freezing method was judged to be normal, but no conception occurred in any of the recipient bitches. Two of the five bitches that received transferred embryos (morula to early blastocyst stages) vitrified–warmed using the Cryotop method became pregnant and produced normal pups (1/9 embryos, 11.1% and 1/6 embryos, 17.0%). It was concluded that the Cryotop method was more appropriate for canine embryo cryopreservation than the slow-freezing method, which is used for the cryopreservation of embryos of other mammalian species.
著者
Masanori KOBAYASHI Tatsuya HORI Eiichi KAWAKAMI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.13-0053, (Released:2013-04-30)
被引用文献数
4 7

In healthy male dogs, peripheral plasma testosterone (T), prostaglandin E2 (PGE2), and seminal plasma PGE2 levels were measured before, during, and after ejaculation and semen quality was examined after oral administration of PGE2. Plasma T and PGE2 levels did not change during these periods, but seminal plasma PGE2 level in the first and second fraction was significantly higher than that at 0–5 and 5–10 min after the start of ejaculation of the third fraction. Semen volume but not quality increased after PGE2 administration. In conclusion, large amounts of PGE2 are released from the prostate gland during the early part of ejaculation and that PGE2 plays an essential role in secretion of seminal plasma.
著者
Masanori KOBAYASHI Chie TSUZUKI Marika KOBAYASHI Hinano TSUCHIYA Yume YAMASHITA Kanako UENO Moe ONOZAWA Masato KOBAYASHI Eiichi KAWAKAMI Tatsuya HORI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.21-0174, (Released:2021-05-20)
被引用文献数
1

Oxidative stress owing to an imbalance between reactive oxygen species and antioxidants, such as coenzyme Q10 (CoQ10), is a major contributor to male infertility. We investigated the effects of the reduced form of CoQ10 (ubiquinol) supplementation on semen quality in dogs with poor semen quality. Three dogs received 100 mg of ubiquinol orally once daily for 12 weeks. Semen quality, serum testosterone, and seminal plasma superoxide dismutase (SOD) activity were examined at 2-week intervals from 2 weeks before ubiquinol supplementation to 4 weeks after the treatment. Ubiquinol improved sperm motility, reduced morphologically abnormal sperm, and increased seminal plasma SOD activity; however, it had no effect on testosterone level, semen volume, and sperm number. Ubiquinol supplementation could be used as a non-endocrine therapy for infertile dogs.
著者
Eiichi KAWAKAMI Tatsuya HORI Toshihiko TSUTSUI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.61, no.10, pp.1107-1111, 1999-10-25 (Released:2000-04-12)
参考文献数
33
被引用文献数
12 14

The effects of a cryptorchid testis on the contralateral testis were investigated after artificially producing unilateral cryptorchidism in 8 beagle dogs. Bilateral testicular biopsy and collection of spermatic vein blood and peripheral vein blood were performed at the time of the operation to produce the cryptorchidism and 52 weeks later. The testicular tissue was used for histological examination by light microscopy and measurement of the testicular transferrin (Tf) concentration by enzyme immunoassay. Plasma testosterone (T), estradiol-17β (E2), and luteinizing hormone (LH) levels were measured by radioimmunoassay. Semen was collected weekly and its quality was examined. No spermatogenesis was observed in the cryptorchid testes at 52 weeks after the operation, and the number of germ cells in the contralateral testes had decreased but the number of Sertoli cells did not change. The Tf concentration in both testes had also decreased. The mean total number of sperm between 48 and 52 weeks after the operation (194 × 106) was less than half the number before the operation (510 × 106). Mean spermatic vein plasma T levels (51 ng/ml) in the cryptorchid testes 52 weeks after the cryptorchid operation were significantly lower than before the operation (91 ng/ml; P<0.05). By contrast, spermatic vein plasma E2 levels (80 pg/ml) were significantly higher than the values before the operation (51 pg/ml P<0.05). The peripheral plasma LH levels decreased. These findings indicate that a large quantity of E2 secreted by the cryptorchid testis inhibits the endocrine and spermatogenic functions of the contralateral testis in the dog. In particular, it is assumed that dysfunction of the contralateral testis is associated with Sertoli cell dysfunction suggested by the low Tf concentration.
著者
Masanori KOBAYASHI Tatsuya HORI Eiichi KAWAKAMI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.18-0108, (Released:2018-06-22)

Two dogs with low plasma testosterone (T) levels and poor semen quality were administered one tablet of 12.5 mg clomiphene citrate orally per day at 2-day intervals for 4 weeks. Plasma T levels, total sperm count, and sperm motility in both dogs temporarily increased between 3 and 6 weeks after the start of treatment. These results indicate that poor semen quality in dogs with low plasma T level can be improved by oral administration of clomiphene citrate.
著者
Eiichi KAWAKAMI Masanori KOBAYASHI Tatsuya HORI Takeharu KANEDA
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.77, no.12, pp.1711-1714, 2015 (Released:2016-01-01)
参考文献数
15
被引用文献数
1 13 1

Four dogs with poor semen quality, low seminal plasma superoxide dismutase (SOD) activity and low blood plasma testosterone (T) levels were orally administered one vitamin E tablet containing 50 mg α-tocopheryl acetate per dog daily for 4 weeks. The mean values of semen quality were temporarily improved after the start of vitamin E treatment and the values of 4, and 5 weeks after that were significantly different from those before the treatment (P<0.05–0.001). The mean blood plasma T and seminal plasma SOD activity values slightly increased in the 4 dogs after the treatment. The results of the present study indicate that poor semen quality in dogs with low seminal plasma SOD can be improved by vitamin E treatment.
著者
Eiichi KAWAKAMI Masanori KOBAYASHI Tatsuya HORI Takeharu KANEDA
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.15-0294, (Released:2015-08-02)
被引用文献数
1 13

Four dogs with poor semen quality, low seminal plasma superoxide dismutase (SOD) activity and low blood plasma testosterone (T) levels were orally administered one vitamin E tablet containing 50 mg α-tocopheryl acetate per dog daily for 4 weeks. The mean values of semen quality were temporarily improved after the start of vitamin E treatment and the values of 4, and 5 weeks after that were significantly different from those before the treatment (P<0.05–0.001). The mean blood plasma T and seminal plasma SOD activity values slightly increased in the 4 dogs after the treatment. The results of the present study indicate that poor semen quality in dogs with low seminal plasma SOD can be improved by vitamin E treatment.
著者
Tatsuya HORI Tetsuya ATAGO Masanori KOBAYASHI Eiichi KAWAKAMI
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.14-0421, (Released:2015-02-01)
被引用文献数
2 18

Canine epididymal sperm was collected from the cauda epididymis using two different methods (flushing and mincing) to compare the qualities (the percentage of progressively motile, viable, morphologically abnormal, immature and intact acrosomes) before and after freezing and thawing. No significant difference was noted in the quality of the cauda epididymal sperm immediately after collection and after freezing-thawing between the collection methods, although the mean levels of sperm quality with the flushing method were slightly better than that of the mincing methods. The flushing method is simple and free of blood contamination, although the vas deferens was too small to be perfused in only one dog, and our results suggest that the flushing method is preferable to the mincing method for collecting sperm from the canine cauda epididymis.
著者
Masanori KOBAYASHI Miho WADA Tatsuya HORI Eiichi KAWAKAMI
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.13-0545, (Released:2014-01-16)
被引用文献数
3 10

Superoxide dismutase (SOD) activity in flushings from oviducts and uterine horns of 8 anestrous, 5 estrous, and 7 diestrous bitches was measured. SOD activity in oviductal fluid in estrous bitches was significantly higher than that in anestrous and diestrous bitches (P<0.01). SOD activity in uterine fluid of diestrous bitches was, however, significantly higher than that in anestrous and estrous bitches (P<0.01). Additionally, sperm collected from normal dogs were incubated in MEM and in MEM containing SOD (SOD-MEM) for 24h. The percentages of sperm with viability, motility, and hyperactivation in SOD-MEM were higher than those in MEM. SOD produced in oviduct and uterus may be able to maintain or improve sperm quality and fertility in the dog.
著者
Masanori KOBAYASHI Tatsuya HORI Eiichi KAWAKAMI
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.75, no.9, pp.1249-1252, 2013 (Released:2013-10-01)
参考文献数
20
被引用文献数
2 7

In healthy male dogs, peripheral plasma testosterone (T), prostaglandin E2 (PGE2) and seminal plasma PGE2 levels were measured before, during and after ejaculation, and semen quality was examined after oral administration of PGE2. Plasma T and PGE2 levels did not change during these periods, but the seminal plasma PGE2 level of combined the first and second fractions was significantly higher than those at 0–5 and 5–10 min after the start of ejaculation of the third fraction. Semen volume but not quality increased after PGE2 administration. In conclusion, large amounts of PGE2 are released from the prostate gland during the early part of ejaculation, and PGE2 plays an essential role in secretion of seminal plasma.
著者
Tatsuya HORI Ryuta YOSHIKUNI Masanori KOBAYASHI Eiichi KAWAKAMI
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.13-0303, (Released:2013-10-01)
被引用文献数
6

The objective of the present study was to determine an optimum temperature and extender for short-term transport of canine ejaculated semen. There was no significant difference on the qualities of semen diluted two kinds of extender, egg yolk Tris-citrate fructose (EYT-FC) or glucose (EYT-GC) extender between the 2°C or 8°C or 12°C and 4°C control groups during storage for up to 48 hr, while the 16–24°C groups showed decreased sperm motility during storage for 48 hr. However, 2°C group showed slightly lower sperm motility and slightly higher sperm abnormality than 4°C group. Therefore, we concluded that semen qualities can be maintained for up to 48 hr when canine semen samples are extended with EYT-FC or EYT-GC and stored at the range of 4–12°C.
著者
Eiichi KAWAKAMI Tomoko YAGI Masanori KOBAYASHI Tatsuya HORI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.74, no.2, pp.201-204, 2012 (Released:2012-03-02)
参考文献数
14
被引用文献数
2 2

A Beagle dog (3 years old) that ejaculated high percentages (mean ± SE: 29.1 ± 1.2%) of sperm with a knobbed acrosome abnormality and a low number of sperm and that also had a low plasma testosterone (T) level was given 10 subcutaneous injections of 1 μg of gonadotropin-releasing hormone analogue (GnRH-A) at 3-day intervals. The plasma T level and number of sperm increased 12-14 weeks after the first injection. Although the percentages of sperm with knobbed acrosome abnormality did not change after the GnRH-A therapy, the number of sperm and percentage of actively motile sperm increased after the therapy, and a bitch gave birth to 5 healthy puppies after intravaginal artificial insemination with fresh semen collected 14 weeks after the first injection.