MR vascular imaging with a fast gradient refocusing pulse sequence and reformatted images from transaxial sections

The authors present a method for obtaining magnetic resonance (MR) images of intra- and extracranial vessels from thin contiguous transaxial sections. A section-selective gradient refocusing pulse sequence with a short repetition time caused flow-related enhancement from spins that flowed perpendicular to the transaxial sections. The signal was further enhanced by means of flow compensation gradients to rephase any phase shifts resulting from moving spins in the presence of the imaging gradients. Coronal and sagittal sections, reformatted from multiple transaxial sections, are shown to have excellent vessel contrast without the use of contrast material. These images were obtained in 12 minutes of acquisition time from as many as 60 sections of 3-mm thickness. Such a technique shows significant promise for MR angiography.     

Ovarian cyclicity, hormones, and behavior as markers of aging in female pigtailed macaques (Macaca nemestrina)

Age-related differences in reproductive function were studied to identify variables suitable for a battery of noninvasive tests used to measure aging rate. Twenty-seven adult female pigtailed macaques, ranging in age from 8 to 31 years, were studied in a cross-sectional design. Perineal tumescence, menses, and activity in the home environment were recorded daily. Sexual behavior, when paired with unfamiliar males of three age groups, was observed six times in the early follicular phase of two ovarian cycles. Estradiol, LH, and FSH were measured twice during the same time period. Of the behavioral measures, mount, present, and activity were found to be lower in old than in young females. Of the physiological measures, ovarian cyclicity was less regular, estradiol was lower, and FSH and LH were higher in old compared to young females. Correlations between measures suggested two dimensions of reproductive function, a behavioral dimension and a physiological dimension.     

瘦素有望成为诊治肿瘤的一个关键点

对瘦素与肿瘤的最新研究进展进行综述，并阐明瘦素参与调节肿瘤发生、发展的可能机制，它可能有望成为早期诊治肿瘤的一个关键点。     

Carbohydrate biguanides as potential hypoglycemic agents

A series of monosaccharides containing a biguanide functionality was prepared and evaluated for hypoglycemic activity. Among the analogues prepared were those involving D-glucose substituted on the 6- or 1-position (19 and 24), D-galactose substituted on the 6-position (7), and D-arabinose (31). The target compounds were evaluated in a modified rat glucose-tolerance test (oral glucose load/oral drug, 100 mg/kg). Compounds 8 [6-biguanidino-1,2:3,5-bis-O-(1-methylethylidene)-6-deoxy-al pha-D- glucofuranose] and 23 [methyl 6-biguanidino-6-deoxy-2,3,4-O-tribenzyl-alpha-D-glucopyra nos ide] were the most active, exhibiting nearly equivalent hypoglycemic activity to that of phenformin (1) and metformin (2), as measured by the inhibition of the rise of blood glucose. Compound 31 was somewhat less active with 26% inhibition, as compared to 64% inhibition with 1 and 41% inhibition with 2.     

Growth stimulation of T47D human breast cancer cells by the anti-progestin RU486

Our laboratory has previously reported that physiological levels of progestins stimulate growth of the human breast cancer cell line T47D. We have also determined that the antiprogestin RU486 inhibits this stimulation. Here we present the unexpected finding that RU486 alone also stimulates growth of these breast cancer cells. Thus, RU486 exhibits both antagonist and agonist-like activity, in a manner somewhat reminiscent of the antiestrogen tamoxifen. To our knowledge, this is the first report of stimulation of breast cancer growth by RU486.     

Thyrotoxicosis associated with distant metastatic follicular carcinoma of the thyroid

In a man with metastatic follicular carcinoma of the thyroid, thyrotoxicosis developed after total thyroidectomy and was successfully treated with antithyroid medications. Treatment with radioactive iodine decreased the size of the distant metastasis and eventually diminished thyroid hormone production. Follicular carcinoma complicated by hyperthyroidism requires vigorous control of the hypermetabolic state. Treatment with radioactive iodine can effectively reduce metabolic complications and tumor bulk, and yields a remission rate as high as 33%.     

What advice are oncologists and surgeons in the United Kingdom giving to breast cancer patients about physical activity?

Evidence has shown that physical activity may attenuate the negative physical, psychological and functional effects of treatment in women diagnosed with breast cancer. Physical activity levels also decline substantially during and after completion of treatment for cancer, highlighting the importance of strategies to promote participation in regular physical activity in this population. Oncologists and surgeons may serve as an influential source of motivation to be physically activity in cancer patients, by conveying the importance of a healthy lifestyle. The primary purpose of the present study was to investigate whether oncologists and surgeons routinely discuss physical activity with their breast cancer patients and to investigate the nature of any information/advice provided during consultations. A secondary aim was to examine whether physically active oncologists and surgeons were more likely to provide advice about physical activity to patients, than inactive oncologists and surgeons. A brief postal questionnaire was sent to 710 consultant breast cancer oncologists and surgeons throughout the UK and 102 responded (response rate = 14.4%). Of responders, most (55.9%) did not routinely discuss physical activity with their patients. Amongst oncologists/surgeons (clinicians) who did offer advice, most focussed on discussing the benefits of physical activity for physical and functional health gains and for facilitating weight control and maintenance. A number of clinicians indicated they advised patients that physical activity may decrease risk of recurrence and improve survival, despite the lack of evidence from RCTs to support this suggestion. There was no significant association between the physical activity status of oncologists/surgeons and the likelihood that they discussed physical activity with patients. Educational strategies aimed at encouraging clinicians to promote physical activity in consultations need to be targeted widely amongst the cancer clinician community.