Biomedical subjects

Takehiko Hatano

Publications and source records attributed to Takehiko Hatano.

3 recordsLinked to original sources

PubMed2005

Thoracoscopic diaphragmatic procedures under artificial pneumothorax.

Diaphragmatic plication is technically simple using a conventional operative technique, but it requires a large skin incision and rib injury. We present an alternative technique for thoracoscopic plication of the diaphragm and evaluate the advantages of the procedure. Six patients (five with diaphragmatic eventration and one with diaphragmatic hernia with a sac) ranging in age from 8 to 20 months were treated by this method. Three of the six cases were right-sided, and three were left-sided. The operation was performed under artificial pneumothorax using carbon dioxide gas at 4 mmHg. Three trocars for laparoscopy were inserted at the 4th and 5th intercostal spaces. An adequate operative view was obtained by pressing the diaphragm throughout the operation. The eventrated diaphragm was plicated with several rows of nonabsorbable sutures in the anterolateral-to-posterolateral direction to prevent injury to the main phrenic nerve. A tight diaphragm was confirmed by decompressing the artificial pneumothorax. The technique was successfully performed in all cases, and the patients' postoperative courses were uneventful. During the operation, the hemodynamic effects of carbon dioxide gas at 4 mmHg were minimal. Over a mean follow-up period of 3.1 years (range, 1-6 years), no recurrence of diaphragmatic eventration was seen. Judging from the satisfactory postoperative course, this procedure is suitable for children with all forms of diaphragmatic eventration.

Diaphragmatic Eventration↗

PubMed2003

Prepubertal zearalenone exposure suppresses N-methyl-N-nitrosourea-induced mammary tumorigenesis but causes severe endocrine disruption in female Sprague-Dawley rats.

The effect of prepubertal exposure to zearalenone, an estrogenic mycotoxin, on N-methyl-N-nitrosourea (MNU)-induced mammary tumorigenesis and its influence on reproductive organs were examined in female Sprague-Dawley rats. Prepubertal rats were treated daily with either 0.1 or 10 mg/kg body weight of zearalenone between 15 and 19 days of age and compared with zearalenone-untreated animals (30 rats in each group). Six rats in each group were autopsied at 28 days of age, and their growth was evaluated. All remaining rats were given 50 mg/kg body weight MNU at 28 days of age and followed by monitoring for occurrence of mammary tumors > or =1 cm in diameter. Zearalenone did not affect body weight increase, and mammary glands showed similar development at 28 days of age (time at carcinogen administration). Both low- and high-dose zearalenone treatment significantly reduced incidence of mammary tumors > or =1 cm in diameter but did not influence latency (time between MNU administration and harvest of mammary tumor > or =1 cm in diameter) compared with untreated controls. Zearalenone dose dependently suppressed the number of histologically detected tumors (carcinomas) and multiplicity; the suppression was significant with high-dose treatment. However, high-dose treatment caused significantly earlier vaginal opening, both low- and high-dose treatment significantly caused irregularity of estrous cycle (persistent estrus or prolonged diestrus) at 8 to 10 wk of age, and zearalenone dose dependently increased the number of anovulatory rats (ovaries without newly formed corpora lutea) at 37 wk of age. Thus, short-duration zearalenone treatment in the prepubertal period suppressed subsequent mammary cancer occurrence but also severely damaged ovarian functions. This suggests that ingestion of foods containing zearalenone in the infantile period can have dramatic effects in later life.

Animals↗

PubMedDate not supplied

Nepalese breast cancer in relation to reproductive factors: comparison between Nepalese and Japanese cases.

The characteristics of Nepalese breast cancer in relation to reproductive factors have not been studied. One hundred and nine Nepalese breast cancer patients were compared with 108 Japanese breast cancer patients and the expression of estrogen (ER) and progesterone receptor (PgR) was evaluated immunohistochemically in 27 Nepalese breast cancer cases. In the Nepalese cases, the age at menarche was significantly older (14.1 vs 13.3 years), while the age at menopause was similar (49.0 vs 49.9 years). The mean age at first full-term pregnancy was significantly lower (20.6 vs 26.6 years), the average number of children was significantly larger (3.1 vs 2.1) and the cumulative duration of lactation was significantly longer (26.9 vs 17.1 months) in the Nepalese cases. In both groups, approximately 60% of breast cancer was premenopausal. The average age of Nepalese breast cancer patients, particularly premenopausal breast cancer patients, was significantly lower (38.6 vs 44.9 years). ER and PgR expression was 11% and 15%, respectively, in Nepalese breast cancer. Nepalese breast cancers were in an advanced stage when discovered. Nepalese breast cancer cases, particularly premenopausal breast cancer patients, were seen at a relatively young age with late menarche, early first full-term pregnancy, long duration of lactation and a large number of children, when compared with Japanese cases. Breast cancer in Nepal may involve mechanisms independent of estrogen exposure.

Adult↗