106 research outputs found
Total uterine artery blood volume flow rate in nulliparous women (TVFR) is associated with birthweight and gestation at delivery
OBJECTIVES: To investigate the relationship between total uterine artery blood volume flow rate (TVFR) and birthweight and gestation at delivery and to establish normal ranges of TVFR through pregnancy. METHODS: A prospective cohort study at University College London Hospital, in which 334 nulliparous women booking for antenatal care had measurement of TVFR by transabdominal ultrasound at 12, 20 and 24 weeks. RESULTS: 551 scans were performed. There was a significant and positive correlation between total uterine blood volume flow at 11-13 weeks (TVFR1) and 22-26 weeks (TVFR2) and birthweight. For every 100 unit increase in TVFR1 and TVFR2, there was a 45 g and 27 g increase in birthweight respectively. There was also a positive association between TVFR1 and gestation at delivery, with a 1.4 day increase in gestation for every 100 unit increase of TVFR1. CONCLUSION: Ultrasound measurement of TVFR in the first trimester is significantly associated with both birth weight and gestation at delivery
Multiple growth factor independence in rat mammary carcinoma cells
In previous studies we demonstrated that rat mammary tumor (RMT) cells that are serially transplantable consist of cells that are independent of growth factors strictly required by normal rat mammary epithelial (RME) cells for growth in serum-free culture. The present studies were designed to determine the extent of the growth factor independence of several cell lines derived from these tumors and to determine if the cells that expressed growth factor independence in vitro are also tumorigenic in vivo . Cells from a transplantable mammary carcinoma (8–12 RMT) were seeded into culture in serum-free medium in the absence of either insulin (IN), epidermal growth factor (EGF), or cholera toxin (CT), and cell populations independent of the individual factors were developed. Next, the three growth factor independent populations were tested for their ability to grow in the absence of multiple growth factors. 8–12 RMT cells did not lose proliferative potential when multiple growth factors were deleted from the medium. Indeed, 8–12 RMT cells could be serially propagated in serum-free medium supplemented solely with bovine serum albumin (BSA) and ethanolamine. Cell lines independent of single growth factors were also developed from two other transplantable tumors (1–9 RMT and 7–15 RMT). In contrast to the 8–12 RMT-derived cell lines, deletion of additional growth factors from the media of the 1–9 RMT and 7–15 RMT-derived cells resulted in dramatic losses in growth potential. These results suggest that independence of individual growth factors is mediated by different mechanisms, since cells from different tumors can stably express independence of one, two, or three or more factors. Examination of conditioned media of four different RMT cell lines indicates that independence of EGF is mediated by autocrine factors. By contrast, there is no evidence for an autocrine factor that mediates independence of insulin-like growth factors. Thus, cell lines derived from serially transplantable RMTs are independent of either single or multiple growth factors, and independence of individual growth factors appears to be mediated by separate mechanisms.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44197/1/10549_2005_Article_BF01980969.pd
Phenotypic analysis of fetal blood leucocytes: potential for prenatal diagnosis of immunodeficiency disorders.
Recent technological advances allow the detection and quantitation of subsets of leucocytes using monoclonal antibodies. We have taken advantage of this to study the ontogeny of fetal blood leucocytes, using very small blood samples obtained at fetoscopy. By 14 weeks gestation T cells represent 35 per cent or more of fetal leucocytes and the distribution of the helper/inducer and suppressor/cytotoxic subsets is similar to that of adults. B lymphocytes before 16 1/2 weeks are low (4-20 per cent), but rise to a mean of 28 per cent in 17-26 week fetuses. Granulocytic cells, many of which are phenotypically immature, represent 18-34 per cent of total leucocytes. The methodology employed is very reliable and offers the opportunity for the prenatal diagnosis of some immunodeficiency disorders, since using the same reagents we have diagnosed children with severe combined immunodeficiency shortly after birth
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