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Biomedical subjects

S Campbell

Publications and source records attributed to S Campbell.

At least 289 records · Page 16Linked to original sources
PubMed1996

Intrafollicular hemodynamics before the administration of human chorionic gonadotropin in women at risk of the ovarian hyperstimulation syndrome.

OBJECTIVE: To test the hypothesis that alteration of intrafollicular hemodynamics precedes the ovarian hyperstimulation syndrome (OHSS). DESIGN: A prospective study. SETTING: The IVF unit and the Doppler imaging laboratory of King's College Hospital, London. PATIENTS: Twenty-four women undergoing IVF and considered to have an exaggerated response to ovarian stimulation and hence at risk of OHSS. INTERVENTIONS: Transvaginal Doppler imaging of the intrafollicular blood flow was performed before hCG administration to determine the indexes of intrafollicular hemodynamics. MAIN OUTCOME MEASURES: Moderate or severe OHSS. RESULTS: There was no statistically significant difference in mean age (32.63 +/- 1.77 versus 31.48 +/- 3.87), duration of infertility (6.00 +/- 2.19 versus 5.29 +/- 2.73), maximum peak systolic velocity (0.25 +/- 0.16 versus 0.26 +/- 0.21 m/s), mean of six maximal peak systolic velocity (0.15 +/- 0.04 versus 0.21 +/- 0.10), minimum pulsatility index (0.76 +/- 0.26 versus 0.59 +/- 0.23), mean of six minimal pulsatility indexes (0.89 +/- 0.30 versus 0.79 +/- 0.14), minimum resistance index (0.47 +/- 0.06 versus 0.41 +/- 0.10), and mean of six minimal resistance indexes (0.56 +/- 0.05 versus 0.53 +/- 0.06) of intrafollicular blood flow between the women who developed moderate or severe OHSS and matched controls. CONCLUSION: Measurement of intrafollicular hemodynamics before hCG administration does not predict the development of the OHSS.

Adult↗
PubMed1996

Transvaginal three-dimensional ultrasound: reproducibility of ovarian and endometrial volume measurements.

OBJECTIVE: To assess the reproducibility of ovarian and endometrial volume measurements obtained using transvaginal three-dimensional (3D) ultrasound (US). DESIGN: Prospective clinical study. SETTING: A tertiary referral center for assisted reproduction. PATIENTS: Forty women undergoing ovarian stimulation for IVF-ET using the long protocol of GnRH agonist. INTERVENTION: Three observers independently measured 20 stored ovarian scanned volumes and 20 endometrial volumes. Also, ovarian volume was calculated from three diameters obtained by two-dimensional (2D) US. MAIN OUTCOME MEASURE: Analysis of variance, the paired Student's t-test, and calculation of intraclass and interclass correlation coefficients were used for statistical analysis. RESULTS: Three-dimensional ovarian volume measurements were not significantly different from ovarian volume calculated from three diameters (7.98 versus 7.58 mL). The mean endometrial volume measurement was 3.56 mL. The intraobserver coefficient of variation for both ovarian and endometrial volume was 8%. The interobserver coefficient of variation was 9% for ovarian volume and 11% for endometrial volume. Intraclass and interclass correlation coefficients were 0.95 and 0.95 for ovarian volume and 0.90 and 0.82, respectively, for endometrial volume. CONCLUSION: Transvaginal 3D US produces highly reproducible ovarian and endometrial volume measurements.

Embryo Transfer↗
PubMed1996

Ultrasound diagnosis of polycystic ovary syndrome.

The US diagnostic criteria of the PCO have been refined with each successive advance in US technology. Diagnostic accuracy has evolved from a mere appreciation of overall ovarian size to the recognition of characteristic follicular patterns of distribution and subtle textural changes in the ovarian stroma. The most consistent features are the presence of multiple small follicles arranged around, or scattered through, a dense echogenic ovarian stroma, although recognition of the latter is highly subjective. Sophisticated innovations such as 3D US, together with colour and pulsed Doppler US, should improve the objectivity of observations and allow quantitative analysis of the ovarian stroma, which is known to be the source of the characteristic hyperandrogenaemia in PCOS. Valid comparative studies of women with normal and polycystic ovaries should now be feasible and will hopefully bring us closer to understanding the pathogenesis of this fascinating condition.

Female↗
PubMed1996

Alteration of in vitro human decidual endothelial cell growth, endothelin-1 and prostaglandin secretion, by growth factors and intracellular calcium.

Endothelial cells isolated from umbilical veins (HUVEC) and from decidual biopsies collected at caesarean section delivery (DEC) from both normal (N DEC) and pre-eclamptic (PE DEC) women, were maintained in culture until passage 2, when the effect on growth of removing heparin/ECGS (endothelial cell growth supplement) from the culture medium was assessed, and the effects of heparin-free incubation and of the Ca2+ ionophore A23187 on endothelin-1, prostacyclin and prostaglandin E2 secretion over a 24 h period were examined. Cell growth slowed significantly in all three cell types in the absence of heparin/ECGS, and cell death occurred in 1/3 samples of HUVEC, 4/6 of N DEC, but 0/2 of PE DEC over 4 days. During the 24 h incubation for prostaglandin in medium without these growth factors, there was further cell death in N DEC. The addition of A23187 to this stress led to a reduction in cell number in both N DEC and HUVEC, and to a lesser extent in PE DEC. Prostaglandin and endothelin-1 levels were higher in the absence of heparin/ECGS in all cell types There was significant suppression of endothelin-1 secretion at 24 h incubation, and stimulation of prostaglandin secretion by A23187. Incubation without heparin/ECGS magnified the effect of A23187 on prostaglandin secretion, although the proportional change was similar if compared to controls without heparin/ECGS. Withdrawal of heparin/ECGS from the medium altered the balance of PGE2/PGI2 secretion by HUVEC, but not DEC. Endothelial cells require the presence of heparin/ECGS for optimum growth and viability, and N DEC are particularly dependent on these growth factors. PE DEC appear relatively 'hardy' in this regard. The addition of a further potentially toxic stimulus may result in cell death, and experiments to be conducted in limited medium must take this into account. There are both qualitative and quantitative differences in the effects of these stimuli on secretion of vasoactive substances, between decidual and umbilical vein endothelial cells.

Calcimycin↗
PubMed1996

Blood flow changes in the intraovarian arteries during the periovulatory period: relationship to the time of day.

Intraovarian blood flow was assessed by transvaginal color and pulsed Doppler ultrasound prospectively in six women during the periovulatory period. All patients had regular ovulatory menstrual cycles and a mid-luteal serum progesterone level consistent with spontaneous ovulation in the preceding cycle. Each patient underwent serial transvaginal ultrasound examination and Doppler assessment of blood flow in the ovarian stroma and in the wall of the dominant follicle or corpus luteum. When the mean follicular diameter was > 16 mm or day -2 from the estimated day of ovulation was reached, patients were scanned at 6-h intervals at 06.00, 12.00, 18.00 and 24.00 until follicular rupture, to investigate the presence of circadian rhythms. The pulsatility index (PI) and the maximum peak systolic blood flow velocity (Vmax) were calculated as Doppler indices of impedance to blood flow and velocity, respectively. A venous blood sample was taken at each visit for subsequent hormonal analysis. There was no significant circadian fluctuation in either mean follicular Vmax or mean follicular PI before or after the luteinizing hormone (LH) surge. Similarly, mean Vmax and mean PI in the non-dominant ovarian stroma did not show any significant fluctuation over the same periods. The mean PI in the dominant ovarian stroma showed daily fluctuations with the highest values occurring most commonly at 06.00 and the nadir in the afternoon and late evening. This fluctuation was the reverse of the circadian variation previously demonstrated in the uterine artery. However, in contrast to the uterine artery, comparison between the mean PI values in the dominant ovarian stroma at 06.00 and 18.00 only approached significance after the LH surge. The dominant ovarian stroma Vmax tended to rise during the day, although the differences between 06.00 and 18.00 were also not significant. Although there are fluctuations in Doppler blood flow indices in the dominant ovarian stroma, further studies are necessary to demonstrate whether this represents a significant circadian rhythm.

Adult↗
PubMed1996

Doppler ultrasound of the uterine arteries: the importance of bilateral notching in the prediction of pre-eclampsia, placental abruption or delivery of a small-for-gestational-age baby.

The use of Doppler studies of the uterine arteries in the prediction of pre-eclampsia and intrauterine growth retardation has had mixed success. The introduction of color Doppler imaging and the use of the "notch' to define an abnormal waveform have helped to improve the predictive value of uterine artery Doppler screening. The aim of this study was to evaluate the use of uterine artery Doppler in a group of women of mixed race and parity. This study was a prospective, cross-sectional analysis of 1326 unselected women who were screened with continuous wave uterine Doppler at 19-21 weeks, as part of a fetal anomaly/dating scan. A total of 214 women with abnormal uterine artery waveforms (notching) were referred for assessment at 24 weeks; 191 attended and had color Doppler imaging/pulsed Doppler studies of both uterine arteries. Data from 185 pregnancies were suitable for analysis. There were abnormal uterine Doppler findings (uni- or bilateral notching) in 110 patients at 24 weeks; 48 had bilateral notching. The sensitivity of notching for the prediction of proteinuric pregnancy-induced hypertension (PPIH) was similar in primiparas (76.9%), multiparas (77.7%), African-Caribbean women (82.6%) and Caucasian women (71.4%). The sensitivity of bilateral notching for the prediction of PPIH requiring delivery before 34 weeks was 81.2%, and 57.6% for babies small for gestational age (SGA), with positive predictive values of 27% (PPIH), 31.2% (SGA) and 37.5% (any complication). Patients with persistent bilateral notching are particularly at risk of developing PPIH or delivering an SGA baby before 34 weeks' gestation; they warrant increased surveillance, and may be a group that could benefit from prophylactic therapies.

Abruptio Placentae↗
PubMed1996

The diagnostic value of endometrial thickness and volume measurements by three-dimensional ultrasound in patients with postmenopausal bleeding.

We compared endometrial thickness and volume in patients with postmenopausal bleeding, and examined the value of each parameter in differentiating between benign and malignant endometrial pathology. A total of 103 patients with a history of postmenopausal bleeding were recruited into the study. Patients who were taking hormone replacements therapy or other hormonal preparations with a known effect on the endometrium were excluded. Each patient underwent three-dimensional ultrasonography for the measurement of endometrial thickness and volume. In 97 cases both of these measurements were obtained and the results were compared to the histological diagnosis after endometrial biopsy or dilatation and curettage. Endometrial cancer was diagnosed in 11 patients. The mean endometrial thickness was 29.5 mm (SD 12.59) and the mean volume was 39.0 ml (SD 34.16). In the remaining 86 patients there were eight cases with endometrial hyperplasia and seven with endometrial polyps. The endometrial thickness and volume in patients with benign pathology was 15.64 mm (SD 5.26) and 5.47 ml (SD 6.32), respectively. In 71 patients with atrophic or normal endometrium the mean thickness and volume was 5.29 mm (SD 3.97) and 0.91 ml (SD 1.71), respectively. Receiver operating characteristic curves showed endometrial volume to be superior to endometrial thickness for the diagnosis of endometrial cancer. The optimal cut-off value of endometrial thickness for the diagnosis of cancer was 15 mm, with the test sensitivity of 83.3% and positive predictive value of 54.5%. With the cut-off level of 13 ml for endometrial volume measurement the sensitivity was 100% and the positive predictive value 91.7%. Both the thickness and volume were higher in patients with advanced and less differentiated cancers. The measurements of endometrial volume was superior to that of endometrial thickness as a diagnostic test for the detection of endometrial cancer in symptomatic postmenopausal women.

Aged↗
PubMed1996

Fetal sexing by ultrasound in the second trimester: maternal preference and professional ability.

The study was planned to determine the proportion of parents that wish to know the sex of their fetus at the 20-week anomaly scan, and to investigate our ability to diagnose correctly the sex of the fetus when undertaken as part of a routine scan. A total of 472 patients gave their informed consent. An attempt was made to identify the genitalia as part of the routine scan. No extra time was allowed to determine the sex of the fetus. Altogether 353 (74.7%) women wanted to know the sex, of which four (0.9%) wanted to know but did not want their partners to know. In 50 (10.6%) cases, it was not possible to determine the fetal sex in the time allowed. When the sex was identified, it was correct in 408 (96.7%) cases, and incorrect in 14 (3.3%) cases. Where the parents wanted to know the sex of the fetus, 24 (6.8%) scans were inconclusive, 319 (97%) were correctly identified, and ten (3%) were incorrectly identified (six male, four female). There were no terminations of pregnancy. The majority of prospective parents wish to know the sex of their child, and, in most cases, it is possible to determine the fetal sex at the time of the routine anomaly scan. During the time allowed, the fetal sex was undetermined in one in ten cases, and 3% were sexed incorrectly. If parents wish to know the gender of their fetus, it would appear reasonable to provide this information, provided that the parents are aware of the failure and error rates of sex identification using ultrasound.

Attitude↗
PubMed1996

Diagnosis and treatment of early cervical pregnancy: a review and a report of two cases treated conservatively.

We report two cases of cervical pregnancy which were diagnosed by ultrasound at 5 and 8 weeks' gestation. In both cases a gestational sac was visualized below the internal os and color Doppler examination demonstrated peritrophoblastic blood flow characteristic of early implantation. Both patients were successfully treated with systemic methotrexate. Including these two cases, a total of 83 early cervical pregnancies have been reported in the literature over the last 10 years. Of these, 40 patients were primarily treated by conservative surgery, 40 by non-surgical methods using methotrexate or potassium chloride, and the remaining three by other chemotherapeutic agents. The likelihood of being cured was similar in the surgical and non-surgical groups (odds ratio 1.1; 95% confidence interval 0.4-3.2). However, patients who were primarily treated by surgery were more likely to sustain major hemorrhage (odds ratio 8.0; 95% confidence interval 2.4-26.5) and to require hysterectomy (odds ratio 7.4; 95% confidence interval 0.9-63.8) than those treated medically. This indicates that non-surgical methods should be used for primary treatment of cervical pregnancy, while surgery should be reserved for those patients in whom medical therapy is not successful.

Adult↗
PubMed1996

Blood flow changes in the ovarian and uterine arteries during the normal menstrual cycle.

OBJECTIVE: Our purpose was to study the hemodynamic changes in the uterine and intraovarian vessels during the normal menstrual cycle and to relate the vascular changes to hormonal index values. STUDY DESIGN: Seven women who had bilateral tubal patency, a normal pelvis on laparoscopy, and regular ovulatory cycles underwent serial transvaginal ultrasonography on menstrual cycle day 2, daily from estimated day of ovulation-6, hourly from estimated day of ovulation-2, or when the mean follicular diameter was > 16 mm (whichever was earlier) until 6 hours after follicular rupture and once 7 days after follicular rupture. At each scan uterine and intraovarian blood flow was assessed with transvaginal color Doppler ultrasonography and serum concentrations of follicle-stimulating hormone, luteinizing hormone, estradiol, and progesterone assessed by fluoroimmunoassay. RESULTS: In one case there was evidence of a luteinized unruptured follicle and the patient was therefore excluded from analysis. In the other six women there was spontaneous ovulation at a mean of 39 hours after the onset of the luteinizing hormone surge. On the side with the dominant follicle, follicular and ovarian stromal peak systolic blood flow velocity rose significantly during the menstrual cycle with no significant change in pulsatility index. The changes in blood flow velocity correlated significantly with changes in serum follicle-stimulating hormone, luteinizing hormone and progesterone concentrations. There were no significant changes in either blood flow velocity or pulsatility index in the contralateral ovary. Uterine artery time-averaged maximum velocity on the side of the developing ovarian follicle increased during the menstrual cycle with no significant change in the contralateral vessel. Uterine artery pulsatility index on the side of the developing follicle declined during the midluteal phase and was significantly lower than on the contralateral side. The changes in time-averaged maximum velocity correlated with the changes in serum estradiol and progesterone concentrations. CONCLUSION: The vascular changes in the wall of the dominant ovarian follicle and ovarian stroma during the menstrual cycle are consistent with activity of angiogenic-like factors. The decline in uterine artery resistance during the midluteal phase may reflect optimal vascularity for implantation of the blastocyst.

Adult↗
PubMed1996

Localization of endothelin receptors in human uterus throughout the menstrual cycle.

Quantitative autoradiography employing the ETA selective ligand [125I]PD 151242 and the ETB selective ligand [125I]BQ3020 was used to assess the localization of ETA and ETB receptors in human uterus throughout the menstrual cycle. ETA and ETB receptors were present in endometrium and myometrium across the menstrual cycle. In myometrium, neither ETA nor ETB receptor density showed any detectable change across the menstrual cycle. ETA receptors were expressed in stroma throughout the endometrium and showed an increase in density in proliferative endometrium compared with secretory and menstrual endometrium. Endometrial ETB receptors were expressed at low density in the proliferative phase. In the early secretory phase there was an increase in ETB receptor density in the glandular epithelium of the basal region of the endometrium but not in functional endometrium. In the late secretory phase ETB receptor expression was increased in glandular epithelium throughout the endometrium. The highest density of ETB receptors was seen in menstrual endometrium, where they were present in stromal as well as epithelial cells. These results suggest that ovarian steroid hormones may play a role in the control of expression of ETA and ETB receptors in endometrial stromal and epithelial cells respectively.

Autoradiography↗
PubMed1996

Associations between ultrasound indices of follicular blood flow, oocyte recovery and preimplantation embryo quality.

The aim of this study was to elucidate possible relationships between ultrasound indices of follicular blood flow, oocyte recovery and the subsequent production and morphological quality of preimplantation embryos. A total of 27 women with bilateral tubal occlusion, undergoing treatment for infertility by in-vitro fertilization and embryo transfer, contributed data from 29 cycles. Transvaginal ultrasonography with colour Doppler imaging and pulsed Doppler spectral analysis was used to obtain indices of blood flow for each follicle immediately before it was aspirated. The main outcome measures for each follicle were the pulsatility index, peak systolic velocity, recovery or non-recovery of an oocyte and the subsequent production or non-production of an embryo. A total of 126 follicles were studied, 102 oocytes were recovered and 58 embryos (49 at grades I or II) were produced. There were six clinical pregnancies (pregnancy rate 27.3% per embryo transfer, 22.2% per patient). There was a significant correlation (P < 0.0001, chi2 test) between whether or not follicular blood flow was detected and whether or not an oocyte was recovered. The sensitivity of a test based on the presence of detectable blood flow and the subsequent recovery of an oocyte was 74% and the positive predictive value was 93%. The peak systolic velocity (PSV, measured in cm/s, mean +/- SD) in follicles with detectable blood flow was significantly higher in follicles that were associated with the production of a preimplantation embryo (19.7 +/- 10.8) compared with those that were not (9.9 +/- 5.3, P < 0.0001, Student's t-test). There was a 70% chance of producing a grade I or II embryo if the follicular blood velocity was >/=10 cm/s, compared with 14% if the PSV was <10 cm/s, or 18% if no blood flow was detected. We conclude that there is a physiological relationship between follicular blood velocity, oocyte recovery and the production of a high-grade preimplantation embryo, which may form the basis of a useful clinical test.

Adult↗
PubMed1996

Ultrasound derived indices of follicular blood flow before HCG administration and the prediction of oocyte recovery and preimplantation embryo quality.

The principal aim of the study was to relate ultrasound-derived indices of blood flow in individual follicles on the day of, but before, the administration of human chorionic gonadotrophin (HCG) to the subsequent recovery of oocytes and the production of preimplantation embryos. Data were obtained from 21 women (aged 29-43 years) with bilateral tubal occlusion, who were undergoing treatment by in-vitro fertilization (IVF) and embryo transfer. Transvaginal ultrasonography with colour Doppler imaging and pulsed Doppler spectral analysis were used to measure follicular volume and derive indices of blood flow. The end-points for each follicle were the volume, peak systolic velocity (PSV), pulsatility index (PI), and the recovery or non-recovery of an oocyte, the subsequent production or non-production of a preimplantation embryo and the morphological grade of each embryo. A total of 94 follicles were studied; 74 oocytes were recovered (79%) and 40 embryos (33 grade I or II) were produced. There were four clinical pregnancies (pregnancy rate 25.0% per transfer, 19.0% per patient). There was a significant correlation between whether or not follicular blood flow was detected and whether or not an oocyte was recovered (P < 0.05, chi 2 test). The values for volume and PI were not clinically useful. The PSV (cm/s, mean +/- SD) was higher in follicles that were associated with the production of an embryo (12.7 +/- 5.9) compared with those that were not (8.5 +/- 5.0; P < 0.05, Student's t-test). The probability of producing a grade I or grade II embryo was 75% if the PSV was > or = 10 cm/s. The corresponding value was 40% if the PSV was < 10 cm/s and 24% if blood flow was not detected (i.e. PSV < 3 cm/s). There was a significant increase (P < 0.05, Student's t-test) in the PSV before aspiration in those follicles associated with the subsequent production of an embryo. We conclude that the value for PSV, before the administration of HCG, can be used to identify follicles with a high probability of producing an oocyte and a high grade preimplantation embryo. The information may also be used to time the administration of HCG to achieve the optimum number and quality of embryos for patient management.

Adult↗
PubMed1996

In-vivo study of diazepam transfer across the first trimester human placenta.

Diazepam transfer by the first trimester human placenta was investigated at pregnancy termination between 6 and 12 weeks of gestation. Fetal fluid samples were obtained from the exocoelomic and amniotic cavities of 65 pregnancies between 8 and 25 min following the i.v. administration of 0.1 mg/kg diazepam to the mother. Diazepam was detected in one-third of coelomic fluid samples and two-thirds of amniotic fluid samples. Maternal serum and urine diazepam concentrations correlated negatively and positively respectively, with time from drug injection to sampling. Individual diazepam concentrations were low on the fetal side, and the corresponding concentrations were independent of maternal serum concentrations and the time from drug injection to sampling. Amniotic fluid diazepam content increased significantly with advancing gestational age. A multiple regression analysis showed that the diazepam content of the coelomic fluid was not influenced by maternal serum diazepam concentration, the time from drug injection to sampling or gestational age, whereas only gestational age contributed to the diazepam content of amniotic fluid. These data demonstrate that the placental transfer of diazepam occurs from week 6 of gestation, indicate a preferential transfer of this drug to the amniotic cavity and suggest that diazepam may accumulate in fetal circulation and tissues during organogenesis.

Adult↗
PubMed1996

A comparison of the inactive urinary kallikrein:creatinine ratio and the angiotensin sensitivity test for the prediction of pre-eclampsia.

OBJECTIVE: To determine the relation between the inactive urinary kallikrein: creatinine ratio (IUK:Cr) and the angiotensin sensitivity test (AST) at 28 weeks of gestation and to assess each as a screening test for pre-eclampsia. DESIGN: Prospective interventional study. SUBJECTS: Four hundred and fifty-nine normotensive nulliparous women recruited from hospital antenatal clinics. SETTING: John Radcliffe Maternity Hospital, Oxford, and Queen Charlotte's and Chelsea Hospital, London. INTERVENTIONS: A urine sample for IUK:Cr measurement was provided before performing the AST at 28 weeks of gestation. Those women who demonstrated increased sensitivity to angiotensin II were entered into a randomised placebo controlled trial of low dose aspirin for the prevention of pre-eclampsia (CLASP). MAIN OUTCOME MEASURES: The development of pre-eclampsia. RESULTS: The IUK:Cr ratio was significantly lower in those women who showed increased sensitivity to angiotensin II (P < 0.0001 Student's t test). The sensitivity and specificity for detecting pre-eclampsia were, respectively, 22% and 85% for the AST and 67% and 75% for the IUK:Cr. Low-dose aspirin (60 mg) had no effect on the pregnancy outcome. CONCLUSION: There appears to be some relation between the IUK:Cr and AST tests in pregnancy. However, in this population, the IUK:Cr ratio was a better screening test for pre-eclampsia than the AST, but overall neither test was a powerful predictor for the syndrome.

Angiotensin II↗