Fetal growth restriction: a workshop report

Intrauterine growth restriction (IUGR) is associated with significantly increased perinatal morbidity and mortality as well as cardiovascular disease and glucose intolerance in adult life. A number of disorders from genetic to metabolic, vascular, coagulative, autoimmune, as well as infectious, can influence fetal growth by damaging the placenta, leading to IUGR as a result of many possible fetal, placental and maternal disorders. Strict definitions of IUGR and of its severity are needed in order to eventually distinguish among different phenotypes, such as gestational age at onset, degree of growth restriction and presence of hypoxia. This report explores and reviews some of the most recent developments in both clinical and basic research on intrauterine growth restriction, by seeking mechanisms that involve genetic factors, utero-placental nutrient availability and vascular growth factors. New exciting findings on the genomic imprinting defects potentially associated with IUGR, and the placental anomalies associated with the decreased nutrient transport are summarized. Moreover, recent data on angiogenic growth factors as well as new information arising from application of gene chip technologies are discussed.

Fetal growth restriction: a workshop report

Intrauterine growth restriction (IUGR) is associated with significantly increased perinatal morbidity and mortality as well as cardiovascular disease and glucose intolerance in adult life. A number of disorders from genetic to metabolic, vascular, coagulative, autoimmune, as well as infectious, can influence fetal growth by damaging the placenta, leading to IUGR as a result of many possible fetal, placental and maternal disorders. Strict definitions of IUGR and of its severity are needed in order to eventually distinguish among different phenotypes, such as gestational age at onset, degree of growth restriction and presence of hypoxia. This report explores and reviews some of the most recent developments in both clinical and basic research on intrauterine growth restriction, by seeking mechanisms that involve genetic factors, utero-placental nutrient availability and vascular growth factors. New exciting findings on the genomic imprinting defects potentially associated with IUGR, and the placental anomalies associated with the decreased nutrient transport are summarized. Moreover, recent data on angiogenic growth factors as well as new information arising from application of gene chip technologies are discussed.

Managing genital infection in community family planning clinics: an alternative approach to holistic sexual health service provision

OBJECTIVE

To pilot and evaluate sexually transmitted infection (STI) management in community family planning clinics (FPCs).

METHODS

Number of STI tests taken, positive results, infections treated, contacts traced/treated, referrals to specialist services and time from testing to treatment were documented as well as age and sex of the population tested.

RESULTS

STI tests taken increased from 233 to 308/month and male clients seen increased from 114 to 147/month across all clinics. Chlamydia prevalence rates in one large clinic increased from 6.7% to 11.9%. 82% of those with STIs in this clinic were treated. Of 44 clients treated for chlamydia, 84% had partner notification performed, 0.43 contacts were treated for every client with chlamydia and referrals to specialist services decreased. 70% of STIs were detected in clinic users under the age of 25 and 45.5% of clients tested under the age of 16 had an STI. Before STI treatment was available at FP clinics 52% of clients with STIs attended specialist services after referral and time from testing to treatment was 19 days. Managing STIs in the community increased treatment rates to 82% with a testing to treatment time of 10 days.

CONCLUSIONS

The management of uncomplicated genital infection in community FPCs working in partnership with specialist services is a feasible and effective approach to holistic sexual health service provision.

Conventional digital subtraction x-ray angiography versus magnetic resonance angiography in the evaluation of carotid disease: patient satisfaction and preferences

AIM

To compare conventional digital subtraction x-ray angiography (DSA) and contrast-enhanced magnetic resonance angiography (MRA) of the carotid arteries in terms of patient satisfaction and preferences.

METHODS

One hundred and sixty-seven patients with symptomatic carotid artery disease, who underwent both DSA and MRA, were prospectively recruited in this study. Patients' perceptions of each method were assessed by the use of a questionnaire after each procedure. Main outcome measures were anxiety, pain, satisfaction rate and patient preferences.

RESULTS

DSA generated more anxiety and pain during the procedure, but the severity of these ill-effects was mild. Satisfaction rates for each method were similar. More patients were, however, willing to have a repeat MRA compared with DSA (67 versus 41%). The majority of patients (62%) preferred MRA over DSA (31%). The shorter MRA imaging time was found to be a significant factor in patients' acceptance of the technique. The main reasons cited by patients for their dislike of a particular procedure was noise and claustrophobia for MRA and invasiveness, pain and post-procedural bed rest for DSA.

CONCLUSIONS

MRA is the method that is preferred by the majority of patients, although the actual disutility of DSA may be small. Assuming equal diagnostic accuracy, our data supports replacement of DSA by MRA for routine carotid imaging.

Effect of adding dopexamine to intraoperative volume expansion in patients undergoing major elective abdominal surgery † †This article is accompanied by the Editorial

BACKGROUND

The contribution of low-dose dopexamine to outcome, when given to increase cardiac output in patients already treated with fluids during major abdominal surgery, is not yet known.

METHOD

We carried out a randomized double-blind placebo-controlled trial. All 100 patients studied were given fluid infusions during surgery guided by stroke volume measurements made with an oesophageal Doppler probe. Patients were randomized to receive dopexamine at the rate of 0.25 microg kg(-1) min(-1) or saline 0.9% (control) for the first 24 h after the start of surgery. The primary outcome measure was the incidence of postoperative morbidity.

RESULTS

There were no statistically significant differences between groups in the incidence of postoperative complications, the length of hospital stay, the incidence of morbidity and the use of critical care facilities. The patients randomized to receive dopexamine had significantly more pre-existing disease than the control patients. Mortality in both groups was significantly less than predicted by the POSSUM (Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity) risk prediction score.

CONCLUSION

We could not demonstrate an advantage to using low-dose dopexamine in high-risk patients during major abdominal surgery.

Instrumentation used to measure residential magnetic fields and currents

The equipment used to measure magnetic fields and electric currents in residences is described. The instrumentation consisted of current transformers, magnetic field probes and locally designed and built signal conditioning modules. The data acquisition system was capable of unattended recording for extended time periods. The complete system was calibrated to verify its response to known physical inputs.

Regional and urban Victorian diabetic youth: clinical and quality-of-life outcomes

OBJECTIVES

To compare groups of urban and regional Victorian diabetic children and assess their quality of life, diabetes knowledge, access to services and metabolic control.

METHODS

Forty-seven children from three regional Victorian communities (Horsham, Warrnambool and Sale; n = 16, 18 and 13, respectively) were compared with 120 age-, sex- and duration of diabetes-matched children attending the Royal Children's Hospital (RCH) diabetes clinic in Melbourne. Quality of life, diabetes knowledge, use of services, and metabolic control were assessed using the child health questionnaire (CHQ PF-50/CF-80); a diabetes-knowledge questionnaire; access to a diabetes nurse educator (DNE), dietitian and complication screening; and indices of mean HbA1C (values are taken every 3 months in the 'yearly HbA1C'), respectively.

RESULTS

Comparisons of CHQ data showed that regional diabetic youth scored significantly lower on most subscales. The greatest deficits were seen in areas of mental health, self-esteem, parent impact (emotional) and family cohesion. Diabetes knowledge and median yearly HbA1C for patients were not significantly different between the regional and urban centres (8.1%, 8.9%, 8.4% and 8.6% at RCH, Horsham, Warrnambool and Sale, respectively). Patients in regional centres had reportedly less access to team-based diabetes care.

CONCLUSIONS

Regional youth in Victoria, with similar levels of metabolic control and diabetes knowledge as their urban counterparts, have a markedly lower quality of life, implying a negative synergy between diabetes and the demands of regional lifestyles.

Treatment of systemic lupus erythematosus with mycophenolate mofetil

Mycophenolate mofetil is an immunosuppressive drug that is of established efficacy in renal transplantation. It inhibits the de novo pathway of purine synthesis and therefore lymphocyte proliferation. Mycophenylate mofetil has been shown to ameliorate the severity of renal injury in murine models of lupus nephritis. Recent studies suggest that it may also be effective in the treatment of patients with lupus nephritis when used in conjunction with steroids. These observations need to be confirmed in adequately sized randomised-controlled studies.

Signalling pathways regulating the dephosphorylation of Ser729 in the hydrophobic domain of protein kinase Cepsilon upon cell passage

We have recently demonstrated that in quiescent fibroblasts protein kinase C (PKC) epsilon(95) is phosphorylated at Ser(729), Ser(703), and Thr(566) and that upon passage of quiescent cells phosphorylation at Ser(729) is lost, giving rise to PKCepsilon(87). Ser(729) may be rephosphorylated later, suggesting cycling between PKCepsilon(87) and PKCepsilon(95). Here we show that the dephosphorylation at Ser(729) is insensitive to okadaic acid, calyculin, ascomycin C, and cyclosporin A, suggesting that dephosphorylation at this site is not mediated through protein phosphatases 1, 2A or 2B. We demonstrate that this dephosphorylation at Ser(729) requires serum and cell readhesion and is sensitive to rapamycin, PD98059, chelerythrine, and Ro-31-8220. These results suggest that the phosphorylation status of Ser(729) in the hydrophobic domain at Ser(729) is regulated independently of the phosphorylation status of other sites in PKCepsilon, by a mTOR-sensitive phosphatase. The mitogen-activated protein kinase pathway and PKC are also implicated in regulating the dephosphorylation at Ser(729).

XAFS at the Pacific Northwest Consortium-Collaborative Access Team undulator beamline

The Pacific Northwest Consortium-Collaborative Access Team (PNC-CAT) has begun operating an insertion device beamline at the Advanced Photon Source. The beamline has been extensively used for XAFS studies. This paper summarizes its capabilities, and our initial operational experience. The beamline is based on APS undulator A, and incorporates full undulator scanning. The monochromator is liquid nitrogen cooled and has both Si(111) and Si(311) crystals in a side-by-side configuration. Crystal changes only take a few minutes. The crystals cover the energy range from 3-50 keV with fluxes as high as 2x10(13) ph/sec. Microbeams can be produced using Kirkpatrick-Baez mirrors (spot size 1-3 microm) or tapered capillaries (sub-microm spots). When these optics are combined with a 13-element Ge detector, the beamline provides powerful microbeam imaging and spectroscopy capabilities. Experimental examples from the environmental field and in-situ UHV film growth will be discussed.

Heterogenous nature of flow-mediated dilatation in human conduit arteries in vivo: relevance to endothelial dysfunction in hypercholesterolemia

Flow-mediated dilatation (FMD) of conduit arteries is dependent on an intact endothelium, although the mechanisms are not fully understood. Using high-resolution ultrasound, we examined the role of endothelial mediators in radial artery dilatation in response to transient (short period of reactive hyperemia) and sustained (prolonged period of reactive hyperemia, hand warming, or an incremental infusion of acetylcholine into the distal radial artery) hyperemia. After short episodes of reactive hyperemia, FMD was abolished by local infusion of the nitric oxide synthesis inhibitor N:(G)monomethyl-L-arginine (5.3+/-1.2% versus 0.7+/-0.7%, P:<0.001). In contrast, basal vessel diameter and dilatation after prolonged episodes of reactive hyperemia, hand warming, and distal infusion of acetylcholine were not attenuated by nitric oxide synthesis inhibition. Inhibition of cyclooxygenase or local autonomic nervous system blockade also had no effect on FMD. Patients with hypercholesterolemia exhibited reduced FMD in response to transient hyperemia, but the response to sustained hyperemia was normal. These data suggest heterogeneity of endothelial responses to blood flow that are dependent on the characteristics of the flow stimulus. Dilatation after brief episodes of hyperemia is mediated by release of nitric oxide, whereas dilatation during sustained hyperemia is unaffected by NO synthesis inhibition. Hypercholesterolemia seems to differentially affect these pathways with impairment of the nitric oxide-dependent pathway and preservation of non nitric oxide-mediated dilatation to sustained flow stimuli.

Acute systemic inflammation impairs endothelium-dependent dilatation in humans

BACKGROUND

We tested the hypothesis that endothelial dysfunction underlies the association between an acute inflammatory episode and the transiently increased risk of a cardiovascular event by examining the effects of an experimental inflammatory stimulus on endothelium-dependent vasodilation.

METHODS AND RESULTS

Salmonella typhi vaccine was used to generate a systemic inflammatory response in healthy volunteers. In 12 subjects, dilatation of the brachial artery to flow and to sublingual nitroglycerin (NTG) was recorded (conduit vessel response), and in 6 subjects, venous occlusion plethysmography was used to measure forearm blood flow during intrabrachial infusion of the endothelium-dependent dilators acetylcholine (ACh) and bradykinin (BK) and the endothelium-independent dilators NTG and verapamil (resistance vessel response). Responses were assessed 16 hours before and 8 and 32 hours after vaccination. Vaccination resulted in elevations in white cell count and serum levels of interleukin-6 and interleukin-1 receptor antagonist. Eight hours after vaccination, resistance vessel responses to BK (P:=0.0099) and ACh (P:=0.0414) were markedly attenuated, and brachial artery flow-mediated dilatation was depressed. Resistance vessel responses to verapamil and NTG were unchanged, as was the conduit vessel response to NTG. Thirty-two hours after vaccination, resistance vessel responses to BK and ACh had returned to normal.

CONCLUSIONS

S typhi vaccine generates a mild inflammatory reaction associated with temporary but profound dysfunction of the arterial endothelium in both resistance and conduit vessels to both physical and pharmacological dilator stimuli. This finding might explain the association between infection and inflammation and the enhanced risk of an acute cardiovascular event.

The junctional multidomain protein AF-6 is a binding partner of the Rap1A GTPase and associates with the actin cytoskeletal regulator profilin

The AF-6 protein is a multidomain protein that contains two potential Ras-binding domains within its N terminus. Because of this feature, AF-6 has been isolated in both two-hybrid and biochemical approaches and is postulated to be a potential Ras-effector protein. Herein, we show that it is specifically the first Ras-binding domain of AF-6 that mediates this interaction and that the Ras-related Rap1A protein can associate with this motif even more efficiently than the oncogenic Ha-, K-, and N-Ras GTPases. We further demonstrate that both Ras and Rap1 interact with full-length AF-6 in vivo in mammalian cells and that a fraction of Rap1 colocalizes with AF-6 at the membrane. Dominant active Rap1A, in contrast to Ras, when introduced into epithelial MDCK and MCF-7 cells, does not perturb AF-6-specific residency in cell-cell adhesion complexes. In a pursuit to gain further understanding of the role of AF-6 in junctions, we identified profilin as an AF-6-binding protein. Profilin activates monomeric actin units for subsequent polymerization steps at barbed ends of actin filaments and has been shown to participate in cortical actin assembly. To our knowledge, AF-6 is the only integral component in cell-cell junctions discovered thus far that interacts with profilin and thus could modulate actin modeling proximal to adhesion complexes.

CD28-B7 blockade prevents the development of experimental autoimmune glomerulonephritis

Experimental autoimmune glomerulonephritis (EAG), an animal model of Goodpasture's disease, can be induced in Wistar Kyoto (WKY) rats by a single injection of rat glomerular basement membrane (GBM) in adjuvant. EAG is characterized by circulating and deposited anti-GBM antibodies, accompanied by focal necrotizing glomerulonephritis with crescent formation. The role of T cells in the pathogenesis of EAG remains unclear. T-cell costimulation is provided by ligation of CD28 with either B7.1 (CD80) or B7.2 (CD86) on antigen-presenting cells, and can be inhibited by a soluble form of CTLA4 (CTLA4-Ig) that binds to both B7.1 and B7.2. We examined the effect of CD28-B7 blockade on the development of EAG using native CTLA4-Ig or mutant CTLA4-Ig (Y100F-Ig), which selectively blocks B7.1. Native CTLA4-Ig treatment ameliorated EAG by several measures, including the levels of circulating anti-GBM antibodies, albuminuria, the deposition of IgG and fibrin in the glomeruli, the severity of glomerular abnormalities, and the numbers of infiltrating T cells and macrophages. Y100F-Ig resulted in a similar reduction in the severity of nephritis, but produced no overall reduction in circulating anti-GBM antibodies, although there was a reduction in IgG2a antibodies. We concluded that CD28-B7 blockade reduced autoantibody production and cellular infiltration of glomeruli, and prevented target organ injury. Our results suggest a key role for B7. 1 in costimulation of Th1-like autoimmune responses in the rat, and show that glomerular injury in EAG is largely dependent on cell-mediated mechanisms.

Lack of human leukocyte antigen-G expression in extravillous trophoblasts is associated with pre-eclampsia

Pre-eclampsia, a common complication of first pregnancies, is thought to result from a poorly perfused placenta and may reflect an abnormal maternal immune reaction to the hemiallogenic fetus. Human leukocyte antigen (HLA)-G, a major histocompatibility tissue-specific antigen expressed in extravillous trophoblast cells (fetal-derived), may protect trophoblasts from maternal-fetal immune intolerance and allow these cells to invade the uterus. Through RNA in-situ hybridization analysis, we studied the expression pattern of HLA-G in normal placentae and placentae from pregnancies complicated by severe pre-eclampsia. In normal placenta we found HLA-G expression in the anchoring extravillous trophoblasts with an increasing gradient of expression in the more invasive cells. However, in nine out of 10 pre-eclamptic placentae HLA-G expression was absent or reduced. We conclude that HLA-G is normally expressed in invasive trophoblasts and HLA-G expression is defective in most pre-eclamptic placentae. We propose that trophoblasts lacking HLA-G are vulnerable to attack by the maternal immune system. These defective trophoblasts will be unable to invade the maternal spiral arteries effectively, thereby developing vessels which cannot adequately nourish the developing placenta. This poorly perfused placenta may initiate the systemic cascade of events associated with pre-eclampsia.