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Michael de Swiet

Publications and source records attributed to Michael de Swiet.

10 recordsLinked to original sources

Obstretic medicine: interdisciplinary care for pregnancy and for women wishing to conceive.

The concept of 'obstetrical medicine' was established in the late 19th century, but overshadowed during most of the 20th century by dramatic improvements in surgical, anesthetic, antimicrobial therapeutics, and obstetrical methods and practice. During the last quarter of the 20th century the causes of maternal morbidity and mortality increasingly became pre-existing hereditable and acquired medical disorders and treatable or preventable medical complications of pregnancy. The role of obstetric medicine re-emerged because of surgical, therapeutic, and medical success. New professional associations have been formed to support, through education and research, the growth in numbers of clinicians from many specialties concerned with the medical care of the pregnant patient.

Cause of Death↗

Mid-trimester placentation assessment in high-risk pregnancies using maternal serum screening and uterine artery Doppler.

OBJECTIVE: To determine the value of uterine artery velocimetry and mid-trimester maternal serum AFP/hCG measurements in predicting pregnancy complications in a high-risk group of pregnant patients. METHODS: Eighty-eight patients with chronic hypertension, previous preeclampsia, and thrombophilia were included. Maternal serum AFP/hCG was examined between 15-16 weeks gestation. Levels > 3 multiple of median (MoM) for hCG and > 2 MoM for AFP were considered abnormal. Color Doppler ultrasound was performed at 23-24 weeks gestation. Diastolic notching and pulsatility index (PI) above the 95th percentile were considered abnormal. RESULTS: Thirty-three patients had abnormal uterine artery waveform: 8 patients had abnormal maternal serum hCG and 5 had abnormal maternal serum AFP. Bilateral abnormal uterine artery waveform was associated with pregnancies complicated by lower gestational age at delivery (p=0.05) and birth weight (p<0.01), higher rates of preeclampsia (p=0.006), SGA (p=0.0001), preterm delivery (p=0.0001), and cesarean section rate (p<0.0001) in comparison to patients with normal uterine artery Doppler. Pregnant women with elevated hCG had higher rates of preeclampsia (p=0.006); preterm delivery (p=0.005) and SGA (P=0.03) and, lower birth weight (p=0.001). No significant differences were noted for clinical outcomes according to AFP data. Conclusions. Abnormal uterine artery waveform is superior to maternal serum hCG for identification of placental pathology leading to preterm delivery, low birth weight, and preeclampsia in high-risk pregnant patients.

Adult↗

Association of raised titres of antibodies to Chlamydia pneumoniae with a history of pre-eclampsia.

OBJECTIVE: To establish the prevalence of Chlamydia pneumoniae (C. pneumoniae) infection in a pregnant UK population and to investigate whether C. pneumoniae infection is more common in women with a previous history of pre-eclampsia. DESIGN: Prospective study. SETTING: Academic Hospital. POPULATION: Ninety-one pregnant women (54 parous and 37 nulliparous) at 16-22 weeks of gestation were studied. Of the parous women, 32 had a previous history of pre-eclampsia. METHODS: Peripheral blood was drawn for C. pneumoniae antibodies between 16-22 and 28-40 weeks of gestation. C. pneumoniae antibodies were measured using a solid-phase enzyme immunoassay. According to pregnancy outcome, women were categorised into normal, gestational hypertension and pre-eclampsia groups. MAIN OUTCOME MEASURES: Serum levels of IgG, IgA and IgM C. pneumoniae antibodies. RESULTS: Prevalence of seropositivity to C. pneumoniae was 77%. Parous women had significantly higher levels of IgA and IgM C. pneumoniae antibodies than nulliparous women (P < 0.04). Parous women with previous pre-eclampsia were found to have higher levels of antibodies than parous women with a normal obstetric history (P< or = 0.003). There was no difference in the antibody levels in women with different pregnancy outcomes. CONCLUSIONS: The longitudinal data do not indicate an association between C. pneumoniae infection and pre-eclampsia. However, the subgroup analysis of parous women demonstrated raised C. pneumoniae antibodies in the women with previous pre-eclampsia, and therefore suggests that there may be an association between C. pneumoniae and the disease in this group.

Adult↗

Preeclampsia with abnormal liver function tests is associated with cholestasis in a subgroup of cases.

OBJECTIVE: To investigate whether women with preeclampsia and abnormal liver function tests have raised serum bile acids. DESIGN: Measurement of serum bile acids in serum specimens collected at the John Radcliffe Hospital, Oxford. SETTING: Imperial College School of Medicine. SAMPLE: Stored sera from 37 women with preeclampsia and abnormal liver function tests and from 19 controls. METHODS: Enzymic total bile acid assay. MAIN OUTCOME MEASURES: Total bile acid levels. RESULTS: Women with preeclampsia and abnormal liver function tests had higher median bile acid levels than controls (5.7 vs. 3.2, p = 0.01). The reason for the raised median serum bile acid levels in the patient group is that three (8%) women with preeclampsia had markedly raised serum bile acids levels. There were no obvious clinical or biochemical features specific to these patients. CONCLUSIONS: The pathological mechanisms causing hepatic impairment in some women with preeclampsia may predispose to cholestasis. As some women with preeclampsia and abnormal liver function complain of pruritus, we recommend checking the serum bile acids in this group of women. If these acids are raised the fetal prognosis may be adversely affected.

Adrenergic alpha-Agonists↗

Taurocholate induces changes in rat cardiomyocyte contraction and calcium dynamics.

Obstetric cholestasis is characterized by raised bile acids, and can be complicated by intrauterine death. We have shown that the bile acid taurocholate causes loss of synchronous beating, bradycardia and cessation of contraction in cultured rat cardiomyocytes [Williamson, Gorelik, Eaton, Lab, de Swiet and Korchev (2001) Clin. Sci. 100, 363-369]. The aim of the present study was to investigate the effect of taurocholate on cardiomyocytes further. We demonstrated a reduced rate of contraction and proportion of beating cells when rat cardiomyocytes were exposed to increasing concentrations of taurocholate (0.1-3.0 mM); more marked at higher concentrations (P<0.001). Using scanning ion-conductance microscopy, we also demonstrated reduced amplitude of contraction and calcium transients with taurocholate. Our observations indicate that taurocholate affects calcium release from the sarcoplasmic reticulum and this parallels changes in contractile function. The relationship between the contraction amplitude and calcium transient is not linear, particularly at higher concentrations of taurocholate. We observed different effects in individual cultured neonatal cells; a reversible reduction in rate and amplitude of contraction in some, and irreversible oscillatory (fibrillatory) cessation of beating in others. The effects were more marked with higher concentrations. The contraction amplitude was also reduced in adult cardiomyocytes. The changes were reversible following removal of taurocholate in adult, but not in neonatal, cardiomyocytes exposed to higher concentrations (>0.3 mM) (P<0.001). In conclusion we have demonstrated that the bile acid taurocholate can cause different types of dysrhythmia in individual cardiomyocytes. These results provide further support for the hypothesis that obstetric cholestasis may produce cardiac-related sudden intrauterine death.

Animals↗