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P Bennett

Publications and source records attributed to P Bennett.

At least 109 records · Page 6Linked to original sources
PubMed1994

The relative abundance of type 1 to type 2 cyclo-oxygenase mRNA in human amnion at term.

The onset of labor in humans is associated with an increase in prostaglandin production. One of the key steps is the conversion of arachidonic acid to prostaglandin E2 by cyclo-oxygenase (Cox). Cox has been found to exist as two distinct genes, Cox-1 and Cox-2. We have used RT-PCR to study the relative abundance of mRNA from each Cox gene in amnion at term. Quantitation of PCR efficiency indicated an approximate 100 fold excess of Cox-2 messenger RNA over that for Cox-1. These data point to the importance of Cox-2 in the increased prostaglandin synthesis associated with labor. Further studies should therefore focus on the control mechanisms for Cox-2.

Amnion↗
PubMed1994

Human maternal uniparental disomy for chromosome 16 and fetal development.

Two severely growth-retarded fetuses found to have maternal uniparental disomy (UPD) for chromosome 16 and trisomy 16 placental mosaicism both had an unfavourable outcome. Antenatally, the first case was complicated by an unexplained raised maternal serum alpha-fetoprotein concentration, preterm premature rupture of the membranes, and growth retardation detectable at 21 weeks' gestation, whilst the other had an unexplained raised maternal serum human chorionic gonadotrophin level, a two-vessel cord on ultrasound, and cessation of growth at 25 weeks. At post-mortem, both babies had an imperforate anus. Fetal maternal UPD may explain the poor outcome that occurs in some cases of confined placental mosaicism for chromosome 16 and is also associated with specific fetal abnormalities.

Adult↗
PubMed1994

Cognitive-behavioural interventions in cardiac rehabilitation.

Evidence pertaining to the efficacy of cognitive-behavioural interventions, broadly defined, in cardiac rehabilitation is reviewed. Primary concerns lie with risk reduction and with the amelioration of psychological distress following myocardial infarction. The available data permit few definitive conclusions. The available data, on balance, suggest that programmes targeted at reducing Type A behaviours, smoking cessation, increasing exercise, or which teach stress management techniques, may be effective in reducing psychological distress and increasing effective coping, although frequently only in the short-term; it is more difficult to point to long-lasting advantage in this context. In addition, psychological interventions of this sort would seem to be associated with positive behavioural change. However, there is, as yet, little concerted evidence that such changes afford benefits in terms of coronary heart disease mortality or morbidity. Nevertheless, the pessimism of these conclusions may reflect shortcomings in study design and the failure to optimally match patients to programmes rather than an intrinsic lack of efficacy of the interventions.

Adaptation, Psychological↗
PubMed1994

The expression of phospholipase A2 and lipocortins (annexins) I, II and V in human fetal membranes and placenta in association with labour.

We have studied the expression of the cellular, type two phospholipase A2 and lipocortins (annexins) I, II and V in human amnion, chorion-decidua and placenta using northern analysis. We found no difference in the expression of phospholipase A2 or lipocortin V in tissues obtained before or after labour. Lipocortin I expression was found to decrease in amnion and placenta but increase in chorion decidua with the onset of labour, while expression of lipocortin II increased only in amnion. These results support the hypothesis that the increased phospholipase A2 activity in the fetal membranes and placenta which is associated with labour is not due to increased phospholipase A2 gene expression, but that post translational control of phospholipase A2 activity may be mediated through changes in lipocortin I expression.

Annexin A1↗
PubMed1994

Sex hormone levels in postmenopausal women with advanced metastatic breast cancer treated with CGS 169 49A.

30 postmenopausal patients with metastatic breast cancer were treated with three different doses of fadrozole hydrochloride (CGS 169 49A), a non-steroidal competitive aromatase inhibitor. The effect of 0.5, 1 and 2 mg given twice daily upon the levels of oestrogens, their androgen precursors and upon the concentration of sex hormone binding globulin (SHBG) was investigated after 1 and 3 months and then every 3 months until progression of disease. A significant reduction in the serum concentration of oestrone (P < 0.0001) was obtained at all doses. Also, the serum concentration of oestrone sulphate was significantly reduced (P < 0.0001). However, after 1 month, the concentration was significantly different from pretreatment levels (P < 0.01) only at the 4 mg daily dose. A decline was also observed in the concentration of SHBG (P < 0.05), with a concomitant elevation of the percentage non-SHBG-bound oestradiol. The androgens, testosterone and dehydroepiandrosterone sulphate, were unaltered during treatment, while androstendione was significantly elevated at the 2 mg daily dose (P < 0.001).

Aged↗
PubMed1994

Clinical utility of fetal RhD typing in alloimmunized pregnancies by means of polymerase chain reaction on amniocytes or chorionic villi.

OBJECTIVE: Our purpose was to describe the clinical utility of a deoxyribonucleic acid amplification method for determining fetal RhD status in alloimmunized pregnancies STUDY DESIGN: Six RhD-negative women with alloimmunized pregnancies and heterozygous partners underwent amniocentesis (n = 5) or chorionic villus sampling (n = 1). Fetal RhD type was determined by polymerase chain reaction and results disclosed to the attending physicians. RESULTS: Knowledge of the fetal RhD status avoided further invasive procedures in two pregnancies and facilitated the timing or performance of intrauterine transfusions in the remainder. CONCLUSIONS: In alloimmunized pregnancies the ability to RhD-type the fetus in amniotic fluid avoids the risks of fetomaternal hemorrhage and increased sensitization associated with fetal blood sampling or chorionic biopsy. This allows more rational pregnancy management, avoiding invasive procedures in the presence of an RhD-negative fetus, or planning therapeutic interventions or offering termination of pregnancy in the presence of an RhD-positive fetus.

Amniotic Fluid↗
PubMed1994

Pre-eclampsia I: the midwife and detection.

Midwives must be alert to the possibility of pre-eclampsia by: Taking accurate and detailed genetic histories. Taking consistent blood pressure measurements. Testing urine for protein at every visit. Observing generalised oedema. Advising clients that headaches and epigastric pain should not be ignored. Fetal monitoring for intrauterine growth retardation.

Female↗
PubMed1993

Immunoreactive inhibin-production in post-menopausal women with malignant epithelial ovarian tumors.

In post-menopausal women with a malignant epithelial ovarian tumor the follicle stimulating hormone (FSH) level was found to be significantly lower compared with healthy controls. We demonstrated immunoreactive (i.r.) inhibin in 20% of controls which was elevated to 60% of women with an ovarian tumor and correlating strongly to FSH in the tumor group (P = 0.0002). Steroid hormone levels were comparable in the two groups. In women with ovarian tumors the survival time for the i.r. inhibin-producing women was found to be 4.6 years compared with 0.9 year, or 5.1 times longer than in the non-producing women (P = 0.002). The site of i.r. inhibin production in these post-menopausal women is unknown, but i.r. inhibin production by the developing ovarian tumor or by the post-menopausal ovary may be regarded as a defense mechanism against an elevated gonadotrophin level (the gonadotrophin theory) which would promote further tumor growth. The recent suggestion that the alpha subunit of inhibin is a tumor suppressor gene is consistent with these results. The serum i.r. inhibin or alpha subunit concentrations might be used as an aid to diagnosis or as a prognostic indicator of survival in women with an ovarian carcinoma.

Aged↗
PubMed1993

The post-operative gonadotropin level in post-menopausal women with epithelial ovarian cancer.

Serial estimates of the post-operative hormone levels were made in 15 women subjected to oophorectomy because of ovarian carcinoma. All women were post-menopausal. Pre-operatively, they had significantly lower follicle stimulating hormone (FSH) levels compared with an age-matched control group. Blood samples were collected after a median time of 8 months (139-378 days). After oophorectomy, significantly higher FSH values were found (P = 0.0002), whereas the luteinizing hormone (LH) values were not significantly changed. The inhibin, estradiol and progesterone values were found to be significantly lowered compared with the pre-operative sample. Total and unbound testosterone levels were significantly lower while dehydroepiandrosterone sulphate (DHEAS) and androstenedione levels were unchanged compared with the original sample and compared with controls. Most likely, estradiol and progesterone are produced by the epithelial malignant tumors, as the post-operative values are completely comparable with the primarily included healthy controls. The FSH is suppressed by inhibin and only to a minor degree by the steroid hormones as indicated by the correlation coefficients. Of great interest is the question whether inhibin production is random, or defensive, lowering the gonadotropin levels or influencing tumor growth in some hitherto unknown fashion.

Aged↗
PubMed1993

The effect of short and long duration exercise on serum erythropoietin concentrations.

The effects of short and long duration exercise on serum erythropoietin concentrations [EPO]s were studied in seven male cross-country skiers of national team standard and eight male marathon runners, respectively. The short duration exercise was performed as 60 min of cycling at an intensity of 80%-95% of maximal heart rate. Arterial blood oxygen saturations monitored by pulse-oximetry remained unchanged throughout exercise. The partial pressure of O2 at which haemoglobin was half-saturated with O2 calculated from forearm venous blood gas tension and blood O2 saturation, and the erythrocyte 2,3-diphosphoglycerate did not change significantly during the exercise. Blood lactate concentrations were increased at the end of exercise [from 1.3 (SEM 0.1) to 3.6 (SEM 0.3) mmol.l-1]. The [EPO]s determined (by enzyme-linked immunosorbent assay) pre-exercise, 5 min, 6 h, 19 h, and 30 h after the exercise were unchanged [from 16.1 (SEM 2.6) to 19.1 (SEM 3.2), 17.9 (SEM 3.0), 17.0 (SEM 2.5), and 18.6 (SEM 2.9) U.l-1, respectively]. The [EPO]s were not correlated to the earlier parameters. The long duration exercise consisted of habitual training, a 3 week break from training followed by 2 and 4 weeks of re-training. The [EPO]s, body fat (BF), and serum free-testosterone concentrations determined at the end of each period remained unchanged. The maximal oxygen uptakes were decreased after the break from training and increased during retraining (P = 0.04). Body mass (mb) increased after the break in training (P = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Hormonal factors and prognosis in epithelial ovarian cancer: a multivariate analysis.

When a significantly lower follicle stimulating hormone (FSH) level was found in patients with epithelial ovarian carcinoma, it was decided to analyze the influence of hormonal factors on prognosis. Thirteen factors were tested for prognostic significance in 35 women with epithelial ovarian carcinoma. Age, FIGO-stage, histopathological grade, residual tumor, treatment, gonadotrophins and steroid hormones were tested. By univariate log-rank testing a significantly shorter survival time was found for patients with ascending FIGO-stage, residual tumor mass, estradiol < 0.10 nmol/l, progesterone < 2.0 nmol/l and DHEAS < 1300 nmol/l. In the Cox model the independently significant prognostic factors found were residual tumor mass (P < 0.001) with a risk estimate of 2.65, progesterone (P < 0.05) with a risk estimate of 0.29 for a progesterone level > 2.0 nmol/l and total testosterone (P < 0.03) with a risk estimate of 0.29 for a total testosterone level > 1.15 nmol/l. The present findings, together with the assumption that an elevated gonadotrophin level may induce ovarian tumor growth (the gonadotrophin theory), earlier findings of estrogen and progesterone receptors in human ovarian cancer, and the in vitro demonstration of gonadotrophin-growth-stimulation of human malignant epithelial tumors, justify a thorough investigation of the interaction between steroid hormones and receptors, gonadotrophins, tumor bulk and survival in future research protocols.

Adenocarcinoma↗
PubMed1993

Expression of a common cellular phospholipase A2 by human intrauterine tissues.

A subclone of the three prime (3') end of a human extrapancreatic phospholipase cDNA has been generated using the polymerase chain reaction. This has been used to detect mRNA transcripts in RNA extracted from human amnion, chorion-decidua, placenta and myometrium. The carboxyl-terminus of phospholipases A2 is poorly conserved but hybridisation remained stable under conditions of high stringency. This supports the hypothesis that these tissues express a common cellular phospholipase A2 which is identical to that expressed in platelets.

Amnion↗