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951.
Sheep experience well-documented seasonal changes in reproductive activity and voluntary food intake (VFI). Within the hypothalamus, neurones that express neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) have been implicated in the regulation of reproduction and appetite. In this study, we aimed to determine the extent to which the expression of these two neuronal systems is linked to the seasonal reproductive cycle and/or the seasonal appetite cycle. VFI in our sheep reaches a nadir in August with no difference occurring between December and February. We examined the brains of ovariectomized (OVX) female sheep (n=5-7) that were killed during the breeding season (February) or during the early or late nonbreeding season (August and December, respectively). The brains of these animals were perfused with paraformaldehyde and processed for in situ hybridization histochemistry, using ribonucleotide probes labelled with 35S. The number of NPY and POMC cells and the number of silver grains per cell were counted using an image analysis system. For NPY, the number of cells counted in the arcuate nucleus/median eminence region and the number of silver grains per cell was significantly lower in animals killed during August than in animals killed in February or December. The number of grains per cell over NPY cells was also significantly lower in animals killed during August. For POMC, the number of cells was lower in February than in August and December. Similarly, the number of grains per cell for POMC were lower in February than in August and December. VFI was significantly lower in animals during August than at other times of the year. We conclude that in OVX ewes: (i) NPY gene expression is lower at the time of the year when VFI is reduced and (ii) POMC gene expression is greater at the time of the nonbreeding season than during the breeding season. Because these results were obtained in OVX animals, the changes appear to be independent of alterations in the secretion and/or action of ovarian steroids. Thus, the activity of NPY neurones appears to relate to changes in appetite whereas changes in POMC expression may be relevant to the seasonal breeding cycle.  相似文献   
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PURPOSE: Young women who undergo chemotherapy for breast cancer face serious consequences to their reproductive health. Research in this area has previously focused on men, or on childhood cancer survivors. We sought to explore self-report of reproductive health counseling in young women undergoing chemotherapy for breast cancer. PATIENTS AND METHODS: A total of 166 premenopausal women aged < or = 50 years were recruited from oncology offices in academic and private practices in four northeastern states, as part of a randomized controlled clinical trial aimed at stress reduction. Women were asked a variety of questions regarding diagnosis and treatment, including whether they received any counseling regarding early menopause and fertility issues. RESULTS: Sixty-eight percent and 34% of women reported recalling a discussion with a physician regarding early menopause or fertility, respectively. In multivariate analysis, hormonal therapy and early stage of disease were associated with significantly increased odds of recall of a discussion regarding menopause. Difficulty communicating with medical team was associated with increased odds of recalling a discussion regarding fertility, whereas older age and anxiety in medical situations were associated with decreased odds. CONCLUSION: Many women fail to recall discussions regarding the reproductive health impact of chemotherapy. Demographic, psychological, and disease-related variables are related to recalling such discussions. Counseling about premature menopause and fertility changes is an overlooked aspect of preparation for adjuvant chemotherapy in young premenopausal women with breast cancer. Future research should explore this issue further.  相似文献   
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PURPOSE: Liposomal lurtotecan (OSI-211) is a liposomal formulation of the water-soluble topoisomerase I inhibitor lurtotecan (GI147211), which demonstrated superior levels of activity compared with topotecan in preclinical models. We studied two schedules of OSI-211 in a randomized design in relapsed ovarian cancer to identify the more promising of the two schedules for further study. PATIENTS AND METHODS: Eligible patients had measurable epithelial ovarian, fallopian, or primary peritoneal cancer that was recurrent after one or two prior regimens of chemotherapy. Patients were randomly assigned to receive either arm A (OSI-211 1.8 mg/m(2)/d administered by 30-minute intravenous infusion on days 1, 2, and 3 every 3 weeks) or arm B (OSI-211 2.4 mg/m(2)/d administered by 30-minute intravenous infusion on days 1 and 8 every 3 weeks). The primary outcome measure was objective response, which was confirmed by independent radiologic review, and a pick the winner statistical design was used to identify the schedule most likely to be superior. RESULTS: Eighty-one patients were randomized between October 2000 and September 2001. The hematologic toxic effects were greater on arm A than on arm B (grade 4 neutropenia, 51% v 22%, respectively), as was febrile neutropenia (26% v 2.4%, respectively). Of the 80 eligible patients, eight patients (10%) had objective responses; six responders (15.4%; 95% CI, 6% to 30%) were in arm A and two responders (4.9%; 95% CI, 1% to 17%) were in arm B. CONCLUSION: The OSI-211 daily for 3 days intravenous schedule met the statistical criteria to be declared the winner in terms of objective response. This schedule was also associated with more myelosuppression than the schedule of OSI-211 administered in arm B.  相似文献   
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PURPOSE: To describe clinical features, therapeutic approaches, and prognostic factors in pediatric patients with atypical teratoid/rhabdoid tumors (ATRT) treated at St Jude Children's Research Hospital (SJCRH). PATIENTS AND METHODS: Primary tumor samples from patients diagnosed with ATRT at SJCRH between July 1984 and June 2003 were identified. Pathology review included histologic, immunohistochemical analysis, and fluorescence in situ hybridization for SMARCB1 (also known as hSNF5/INI1) deletion. Clinical records of patients with pathologic confirmation of ATRT were reviewed. RESULTS: Thirty-seven patients were diagnosed with ATRT at SJCRH during the 19-year study interval. Six patients were excluded from this clinical review based on pathologic or clinical criteria. Of the remaining 31 patients, 22 were younger than 3 years. Posterior fossa primary lesions and metastatic disease at diagnosis were more common in younger patients with ATRT. All patients underwent surgical resection; 30 received subsequent chemotherapy. The majority of patients aged 3 years or older received postoperative craniospinal radiation. Two-year event-free (EFS) and overall survival (OS) of children aged 3 years or older (EFS, 78% + 14%; OS, 89% +/- 11%) were significantly better than those for younger patients (EFS, 11% +/- 6%; OS, 17% +/- 8%); EFS, P = .009 and OS, P = .0001. No other clinical characteristics were predictive of survival. Three of four patients 3 years or older with progressive disease were successfully rescued with ifosfamide, carboplatin, and etoposide therapy. CONCLUSION: Children presenting with ATRT before the age of 3 years have a dismal prognosis. ATRT presenting in older patients can be cured using a combination of radiation and high-dose alkylating therapy. Older patients with relapsed ATRT can have salvage treatment using ICE chemotherapy.  相似文献   
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