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Biomedical subjects

Toshitaka Horiuchi

Publications and source records attributed to Toshitaka Horiuchi.

7 recordsLinked to original sources

Abnormal spermatogenesis in mice unable to synthesize ascorbic acid.

Although exposure to environmental toxicants, including endocrine-disrupting chemicals, is thought to be a possible cause of male infertility, the pathogenesis of male reproductive disorders remains unclear. In the present study, we used Gulo-/- mutant mice, which are unable to synthesize ascorbic acid, to study the importance of dietary vitamin C (VC) on spermatogenesis. Regular chow containing approximately 110 mg/kg VC is unable to support the growth of these mutant mice, but a VC supplement in their drinking water (330 mg/L) is able to ameliorate the VC deficiency. Testes of Gulo-/- mutants born from heterozygous mothers without VC supplement (VC-deficient mice) and those born from mothers given a VC supplement (VC-sufficient mice) were examined by morphological and biochemical analyses. Morphological analysis revealed that apoptosis of spermatocytes occurred frequently in VC-deficient mice at 20 days of age. Two-dimensional electrophoresis analysis revealed the specific disappearance of heat-shock protein (Hsp) 70 in the testes of 20-day-old VC-deficient mice. In the present study, the relationship between the apoptosis of spermatocytes and Hsp70 in VC-deficient mice is discussed.

Animals↗

Application study of intracytoplasmic sperm injection for golden hamster and cattle production.

This paper describes several technical improvements and our results in hamster intracytoplasmic sperm injection (ICSI), hamster round spermatid injection (ROSI) and bovine ICSI. The hamster is the mammalian species in which ICSI was first tried to produce fertilized oocytes. However, until recently, no live offspring following ICSI have ever been obtained. We reported the birth of live offspring following hamster ICSI. Improved points to success were 1) performing hamster ICSI in a dark room with a small incandescent lamp and manipulating both oocytes and fertilized eggs under microscope with a red light source and 2) injecting sperm heads without acrosomes. Under controlled illumination, the majority of the oocytes injected with acrosomeless sperm heads were fertilized normally, cleaved, and developed into morulae. Nine live offspring (19%) were born by transfer of hamster ICSI-derived embryos. Furthermore, we reported the birth of live offspring following hamster ROSI. About 70% of oocytes injected with round spermatids broken before injection were fertilized normally and about half of them developed to morulae and blastocysts. Three (5%) live young were born by transfer of hamster ROSI-derived embryos. On the other hand, in cattle, the main improvements were 1) injection of spermatozoa immobilized by scoring their tail just before injection into oocytes, and 2) additional ethanol activation 4 h after ICSI. About 70% of oocytes injected were activated 4 h after ICSI, and about 30% of them developed to blastocysts. Twenty-four live calves (39%) were born by non-surgical transfer of ICSI-derived embryos. Those results shows that, at present, live offspring are able to be obtained following hamster ICSI, ROSI and bovine ICSI, but further improvement is required due to higher production efficiency of offspring.

Acrosome↗

Full-term development of hamster embryos produced by injection of round spermatids into oocytes.

The golden hamster is a mammal in which microinjection of round spermatids into oocytes (ROSI) was first attempted. However, no live ROSI offspring have ever been obtained in this species. This is the first report of live hamster offspring obtained by round spermatid injection. Over 90% of oocytes, injected with round spermatids, were activated without any additional stimulation. The proportion of the oocytes that were fertilized normally and that developed to morulae and blastocysts was higher when the plasma membranes of the spermatids were broken before injection, as compared with when the membranes were left intact. Five percent of 57 ROSI morulae/blastocysts developed into live offspring after transfer to foster mothers.

Animals↗

[Retrospective analysis of postoperative nausea and vomiting after craniotomy].

BACKGROUND: Postoperative nausea and vomiting are important complications after craniotomy. METHODS: One hundred and seventy eight patients who had undergone brain tumor resection at Nara Medical University were retrospectively divided to one of two groups; with or without PONV within 24 hours postoperatively. Variables compared between the groups include gender, age, weight, height, site of surgery (supratentorial versus infratentorial craniotomy), size of brain tumor, type of anesthesia (inhalation versus intravenous anesthesia with nitrous oxide), intraoperative fentanyl dose, duration of surgery as well as anesthesia, and intraoperative posture. RESULTS: PONV occurred in 87 patients (49%). The incidence of PONV in patients undergoing infratentorial craniotomy was significantly higher than that in patients undergoing supratentorial craniotomy (75% vs 45%, P = 0.0011). There were no significant associations between PONV and other variables analyzed. CONCLUSIONS: These results indicate that the incidence of PONV after brain tumor resection is high and infratentorial surgery is a risk factor for PONV. Strategies for the prevention of PONV after craniotomy are required.

Anesthesia, General↗

[Functional characteristics of pharmacy services related to home care--results from two pharmaceutical association surveys in suburban and old town areas].

In order to investigate the implementation about pharmacy services focusing on home care and to identify differences in functional characteristics in accordance with pharmacy location, questionnaire surveys were conducted on all 75 pharmacies belonging to T-City Pharmaceutical Association in a suburban area and on all 161 belonging to K-Ward Pharmaceutical Association in a central downtown district. Using data, a principal component analysis was performed. The following services were investigated: medication guidance for patients and their families; provision of drug information to patients; management of patients' drug history; dispensing; advice to physicians; inquiries; management of prescriptions for home infusion services; sales of items such as over-the-counter [OTC] drugs [commercially available drugs that do not require a physician's prescription]; display and catalogue sales of nursing items; consultation on home care; holding events such as health education programs; guidance for drug management by home visits; and information exchange with other medical professionals and social workers. The results of these surveys were as follows. (1) The following services were regularly performed in both urban and suburban areas: medication guidance for patients and their families; provision drug information to patients; management of patients' drug history; dispensing; advice to physicians; inquiries; and sales of OTC drugs. (2) The following services were not difficiently regularly performed in both areas: display and catalogue sales of nursing items; consultation on home care; holding events such as health education programs; guidance for drug management by home visits; and information exchange. (3) As to principal component analysis, pharmacy functions were divided into 3 components and the dispensing service strongly influenced the functional characteristics in T-City. Whereas, in K-Ward, pharmacy functions were divided into 4 components and consultation and information exchange were strong influences. (4) Home care-relate pharmacy services were closely associated with information exchange on both areas. This implies that enforcing information exchange among pharmacists and other health practitioners and social welfare practitioners is an essential factor to expand implementation of home-care related pharmacy services.

Community Pharmacy Services↗

Full-term development of golden hamster oocytes following intracytoplasmic sperm head injection.

The golden hamster is the mammalian species in which intracytoplasmic sperm injection (ICSI) was first tried to produce fertilized oocytes. Thus far, however, there are no reports of full-term development of hamster oocytes fertilized by ICSI. Here we report the birth of hamster offspring following ICSI. Keys to success were 1) performing ICSI in a dark room with a small incandescent lamp and manipulating both oocytes and fertilized eggs under a microscope with a red light source and 2) injecting sperm heads without acrosomes. All oocytes injected with acrosome-intact sperm heads died within 3 h after injection, while those oocytes injected with acrosomeless sperm heads survived injection. Under illumination with red light in a dark room, the majority of the oocytes injected with acrosomeless sperm heads were fertilized normally (77%), cleaved (91%), and developed into morulae (49%). Of the 47 morulae transferred to five recipient females, nine (19%) developed to live offspring.

Acrosome↗