Factors associated with first thrombosis in patients presenting with obstetric antiphospholipid syndrome (APS) in the APS Alliance for Clinical Trials and International Networking Clinical Database and Repository: a retrospective study.

OBJECTIVE: To evaluate the subsequent rate of thrombosis among women with obstetric antiphospholipid syndrome (Ob-APS) in a multicentre database of antiphospholipid antibody (aPL)-positive patients, and the clinical utility of the adjusted Global Antiphospholipid Syndrome Score (aGAPSS), a validated tool to assess the likelihood of developing new thrombosis, in this group of patients. DESIGN: Retrospective study. SETTING: The Antiphospholipid Syndrome Alliance for Clinical Trials and International Networking Clinical Database and Repository. POPULATION: Women with Ob-APS. METHODS: Comparison of clinical and laboratory characteristics and measurement of aGAPSS in women with Ob-APS, with or without thrombosis, after initial pregnancy morbidity (PM). MAIN OUTCOME MEASURES: Risk factors for thrombosis and aGAPSS. RESULTS: Of 550 patients, 126 had Ob-APS; 74/126 (59%) presented with thrombosis, and 47 (63%) of these women developed thrombosis after initial PM, in a mean time of 7.6 ± 8.2 years (4.9/100 patient years). Younger age at diagnosis of Ob-APS, additional cardiovascular risk factors, superficial vein thrombosis, heart valve disease, and multiple aPL positivity increased the risk of first thrombosis after PM. Women with thrombosis after PM had a higher aGAPSS compared with women with Ob-APS alone [median 11.5 (4-16) versus 9 (4-13); P = 0.0089]. CONCLUSION: Based on a retrospective analysis of our multicentre aPL database, 63% of women with Ob-APS developed thrombosis after initial obstetric morbidity; additional thrombosis risk factors, selected clinical manifestations, and high-risk aPL profile increased the risk. Women with subsequent thrombosis after Ob-APS had a higher aGAPSS at entry to the registry. We believe that aGAPSS is a valid tool to improve risk stratification in aPL-positive women. TWEETABLE ABSTRACT: More than 60% of women with obstetric antiphospholipid syndrome had thrombosis after initial pregnancy morbidity.

Antiphospholipid antibodies in women with severe preeclampsia and placental insufficiency: a case-control study.

Objective Preterm delivery for preeclampsia or placental insufficiency (PREPI) is a clinical criterion for antiphospholipid syndrome (APS), but no prior prospective studies have used the international classification criteria for APS. Our objective is to determine the proportion of women with PREPI who test positive for aPL using international criteria for antiphospholipid antibody (aPL) assays. Methods We conducted a prospective, case-control study of 148 women delivered < 36 weeks because of PREPI compared to 148 controls. PREPI cases delivered < 36 weeks were compared to matched controls. Cases and controls were tested for aPL. Demographic variables were compared with chi-squared and Wilcoxon-rank-sum statistics. Rates of + aPL were compared using adjusted odds ratios (aORs) for maternal body mass index (BMI) and Caucasian race. Positive aPL (+aPL) was defined as lupus anticoagulant (LA), anticardiolipin (aCL) immunoglobulin G (IgG) (GPL) or immunoglobulin M (IgM) (MPL) ≥ 40, or anti-ß2-glycoprotein I (aß2GPI) IgG (SGU) or IgM (SMU) ≥ 40. Results Controls were more likely to be Caucasian (87% vs 70%, p = 0.006) and had lower BMIs (BMI 26 vs 33, p < 0.001). Positive aPL were found more commonly in cases than controls (11.5% vs 1.4%, aOR 8.9 (95% CI 1.9-41.4)). In + aPL cases, 76% had + LA, 41% had + aCL, and 24% had + aß2GPI. Conclusion Women requiring early delivery for PREPI are more likely to have aPL (and thus APS) than controls. This is the first prospective study using both obstetric definitions and laboratory criteria in accordance with APS international criteria.

Preconception antiphospholipid antibodies and risk of subsequent early pregnancy loss.

Objectives To prospectively estimate the association of preconception antiphospholipid antibodies (aPL) with subsequent pregnancy loss using a cohort design. aPL have been associated with recurrent early pregnancy loss (EPL) prior to 10 weeks in previous case-control studies. Prospective ascertainment of pregnancy loss is challenging, as most women do not seek care prior to EPL. Methods Secondary analysis of the Effects of Aspirin in Gestation and Reproduction trial of preconception low-dose aspirin. Preconception anticardiolipin (aCL) and anti-ß2-glycoprotein-I (a-ß2-I) were assessed in 1208 women with one or two prior pregnancy losses and no more than two prior live births. Comparison cohorts were defined by positive aPL (+aPL) or negative aPL (-aPL) status. All women were followed for six menstrual cycles while trying to conceive; if successful, they underwent an ultrasound at 6-7 weeks' gestation. EPL was defined as loss prior to 10 weeks' gestation; embryonic loss was loss after visualization of an embryo but prior to 10 weeks; clinical loss was any loss after visualization of an embryo (with or without fetal cardiac activity detected). Results In total, 14/1208 (1%) tested positive for +aPL. 786/1208 (65%) women had positive human chorionic gonadotropin during the study period, of which 9/786 (1%) had +aPL. Of the 786 pregnant women, 589 (75%) had live births and 24% had pregnancy losses. Women with +aPL experienced EPL at similar rates as women with -aPL, 44% vs 21% (aRR 2.4, 95% confidence interval (CI) 0.5-10.9). Embryonic loss was more common in women with +aCL IgM (aRR 4.8, 95% CI 1.0-23.0) and in women with two positive aPL. Clinical pregnancy loss was more common in women with positive a-ß2-I IgM (50% vs 16.5%, aRR 3.7, 95% CI 1.3-10.8). Conclusion Positive levels of aPL are rare in women with one or two prior pregnancy losses and are not clearly associated with an increased rate of subsequent loss. Clinical trial registration The original source study was registered at ClinicalTrials.gov (#NCT00467363).

Bleeding complications and antithrombotic treatment in 264 pregnancies in antiphospholipid syndrome.

Purpose The purpose of this study was to evaluate the safety of antithrombotic treatments prescribed during pregnancy in patients with antiphospholipid syndrome (APS). Methods This international, multicenter study included two cohorts of patients: a retrospective French cohort and a prospective US cohort (PROMISSE study). Inclusion criteria were (1) APS (Sydney criteria), (2) live pregnancy at 12 weeks of gestation (WG) with (3) follow-up data until six weeks post-partum. According to APS standard of care, patients were treated with aspirin and/or low-molecular weight heparin (LMWH) at prophylactic (pure obstetric APS) or therapeutic doses (history of thrombosis). Major bleeding was defined as abnormal blood loss during the pregnancy and/or post-partum period requiring intervention for hemostasis or transfusion, or during the peripartum period greater than 500 mL and/or requiring surgery or transfusion. Other bleeding events were classified as minor. Results Two hundred and sixty-four pregnancies (87 prospectively collected) in 204 patients were included (46% with history of thrombosis, 23% with associated systemic lupus). During pregnancy, treatment included LMWH ( n = 253; 96%) or low-dose aspirin ( n = 223; 84%), and 215 (81%) patients received both therapies. The live birth rate was 89% and 82% in the retrospective and prospective cohorts, respectively. Adverse pregnancy outcomes occurred in 28% of the retrospective cohort and in 40% of the prospective cohort. No maternal death was observed in either cohort. A combined total of 45 hemorrhagic events (25%) occurred in the retrospective cohort, but major bleeding was reported in only six pregnancies (3%). Neither heparin nor aspirin alone nor combined therapy increased the risk of hemorrhage. We also did not observe an increased rate of bleeding in the case of a short interval between last LMWH (less than 24 hours) or aspirin (less than five days) doses and delivery. Only emergency Caesarean section was significantly associated with an increased risk of bleeding (odds ratio (OR) 5.03 (1.41-17.96); p=.016). In the prospective cohort, only one minor bleeding event was reported (vaginal bleeding). Conclusion Our findings support the safety of antithrombotic therapy with aspirin and/or LMWH during pregnancy in high-risk women with APS, and highlight the need for better treatments to improve pregnancy outcomes in APS. PROMISSE Study ClinicalTrials.gov identifier: NCT00198068.

Laboratory evaluation of anti-phospholipid syndrome: a preliminary prospective study of phosphatidylserine/prothrombin antibodies in an at-risk patient cohort.

Immunoglobulin (Ig)G/IgM autoantibodies to phosphatidylserine/prothrombin (aPS/PT) were evaluated individually and in combination with criteria anti-phospholipid (aPL) tests in a prospectively ascertained cohort of patients at risk for anti-phospholipid syndrome (APS). One hundred and sixty (160) consecutive requests for lupus anti-coagulant (LAC) from the University of Utah Health Sciences Center were identified during 8 weeks. Of these, 104 unique patients had additional requests for cardiolipin (aCL) and/or beta2 glycoprotein I (aß2 GPI) IgG and/or IgM; samples were retained and analysed for aPS/PT, aCL and/or aß2 GPI IgG and IgM antibodies. Following testing, a comprehensive chart review was performed and patients categorized according to their clinical diagnosis. Individual and combined sensitivities, specificities, odd ratios (OR), diagnostic accuracy for specific tests or combinations by receiver operating characteristic (ROC), area under the curve (AUC) analyses and correlations between test results were determined. The sensitivities of aPS/PT IgG/IgM (54·6/45·5%) were lower than LAC (81·8%) but higher relative to aCL IgG/IgM (27·3/0%) or aß2 GPI IgG/IgM (27·3/0%). The best correlation between LAC and any aPL test was observed with aPS/PT (P = 0·002). There was no significant difference in the diagnostic accuracies for any panel with LAC: LAC/aß2 GPI IgG/aCL IgG [AUC 0·979, OR 475·4, 95% confidence interval (CI) 23·1-9056·5, P = 0·0001 and LAC/aß2 GPI IgG/aPS/PT IgG or LAC/aPS/PT IgG/aCL IgG (AUC 0·962, OR 265·3, 14·2-4958·2, P = 0·0001). The high correlation between LAC and aPS/PT IgG/IgM in this preliminary study suggest that this marker may be useful in the evaluation of APS. More studies to determine the optimal aPL antibody tests combination are needed.

Differentiation of genetic abnormalities in early pregnancy loss.

OBJECTIVE: To characterize the types of genetic abnormalities and their prevalence in early pregnancy loss at different developmental stages. We hypothesized that the prevalence of genetic abnormalities in pregnancy loss would differ across developmental stages. METHODS: Women with a pregnancy loss at < 20 weeks' gestation (n = 86) were enrolled at the time of diagnosis. Maternal tissue without a fetal component was found in 13 samples. Chromosomal microarray analysis (CMA) was performed on 74 samples (including two samples from a twin pregnancy); 15 were pre-embryonic (no visible embryo on ultrasound examination), 31 were embryonic (embryo; 6 + 0 to 9 + 6 weeks' gestation) and 28 were fetal (fetus; 10 + 0 to 19 + 6 weeks' gestation) losses. The twin pregnancy was found to be monochorionic diamniotic and was subsequently treated as a single sample in our analysis. Nine samples that underwent CMA were excluded from analysis because of 100% maternal-cell contamination. RESULTS: The overall prevalence of genetic abnormalities differed across developmental stages (9.1% pre-embryonic, 69.2% embryonic and 33.3% fetal; P < 0.01). This difference persisted when comparing pre-embryonic with embryonic samples (P < 0.01) and embryonic with fetal samples (P = 0.02) but not pre-embryonic with fetal samples (P = 0.12). Additionally, the prevalence of aneuploidy differed significantly across developmental stages (0.0% in pre-embryonic samples vs 65.4% in embryonic samples vs 25.9% in fetal samples, P < 0.001). Abnormalities were most common in embryonic cases, followed by fetal and then pre-embryonic. Maternal cell contamination (MCC) was noted in 47.4% of 46,XX cases assessed. CONCLUSIONS: Genetic abnormalities detected by CMA are more likely to occur in the embryonic period than in pre-embryonic or fetal stages. MCC is common in early pregnancy loss and should be excluded when results demonstrate a 46,XX karyotype.

Nonclinical parameters affecting primary cesarean rates in the United States.

OBJECTIVE: Cesarean is the single most common operation in United States and has reached epidemic proportions in recent decades. Our objective was to study the effect of nonclinical parameters on primary cesarean rates in a large contemporary population. STUDY DESIGN: We designed a retrospective multicenter study using data obtained from electronic medical records from 19 U.S. hospitals between 2005 and 2007 (Consortium on Safe Labor Database), which included 145,764 term, singleton, nonanomalous, vertex, live births that included labor. The impact of nonclinical parameters (patient and provider characteristics, time of delivery, institutional policies, and insurance type) was investigated using modified Poisson regression methodology and classification and regression tree analysis. RESULTS: There were 125,517 vaginal and 20,247 cesarean deliveries. Using the multivariable model, the nonclinical parameters with statistical significance for primary cesarean were delivery during evening hours, a male provider, public insurance, and nonwhite race (p < 0.001). CONCLUSIONS: Cesarean rates are associated with several nonclinical factors. Further investigation into these factors might help to develop strategies to reduce their influence and hence the rates of cesarean.

Obstetric antiphospholipid syndrome: current uncertainties should guide our way.

The subject of obstetric antiphospholipid syndrome (APS) has been reviewed dozens of times, and there is little doubt that the international APS community has done well in bringing APS to the attention of clinicians around the world. However, the evolution of clinical practice, at least in the US, also has convinced us that our field would benefit from further clinical study. For example, the number of women diagnosed with 'APS', but who do not meet the revised Sapporo criteria, seems to have increased. It is now common practice for women with recurrent miscarriage or prior fetal death to be treated with heparin, even in the presence of indeterminate or low titer antiphospholipid antibody (aPL) levels and even after only one positive test. In part, this common practice derives from confusion on the part of many clinicians and patients regarding the diagnosis of APS as well as the clinical and laboratory criteria for the syndrome. In part, this derives from the common practice of so-called 'empiric treatment' in US reproductive medicine, often driven as much by patients as by clinicians. This brief commentary focuses on areas of uncertainty that we see as deserving of new or renewed study for the sake of improving our understanding of APS and best patient care.

Clinical relevance of multiple antibody specificity testing in anti-phospholipid syndrome and recurrent pregnancy loss.

We wanted to evaluate whether testing for anti-phosholipid antibodies other than anti-cardiolipin (aCL) and anti-beta-2 glycoprotein I (abeta2GPI) immunoglobulin (Ig)G and IgM identifies patients with recurrent pregnancy loss (RPL) who may be positive for anti-phospholipid syndrome (APS). In a cross-sectional study comprising 62 patients with APS, 66 women with RPL, 50 healthy blood donors and 24 women with a history of successful pregnancies, we tested IgM and IgG antibodies to phosphatidic acid, phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl glycerol, phosphatidyl inositol and phosphatidyl serine with and without beta-2 glycoprotein I (beta2GPI) from a single manufacturer as well as aCL and abeta2GPI antibodies. Diagnostic accuracies of individual and combined anti-phospholipid (aPL) assays were assessed by computing sensitivities, specificities, positive predictive values and negative predictive values together with their 95% confidence intervals. There was a general trend for increased sensitivities in the presence of beta2GPI co-factor with significant effect for certain specificities. The overall combined sensitivity of the non-recommended aPL assays was not significantly higher than that of the aCL and aB2GPI tests. Multiple aPL specificities in RPL group is not significantly different from controls and therefore of no clinical significance.

Detection of viral bioagents using a shear horizontal surface acoustic wave biosensor.

Viruses are of high medical and biodefense concern and their detection at concentrations well below the threshold necessary to cause health hazards continues to be a challenge with respect to sensitivity, specificity, and selectivity. Ideally, assays for accurate and real time detection of viral agents would not necessitate any pre-processing of the analyte, which would make them applicable for example to bodily fluids (blood, sputum) and man-made as well as naturally occurring bodies of water (pools, rivers). We describe herein a robust biosensor that combines the sensitivity of surface acoustic waves (SAW) generated at a frequency of 325MHz with the specificity provided by antibodies for the detection of viral agents. A lithium tantalate-based SAW transducer with silicon dioxide waveguide sensor platform featuring three test and one reference delay lines was used to adsorb antibodies directed against either Coxsackie virus B4 or the category A bioagent Sin Nombre virus (SNV), a member of the genus Hantavirus, family Bunyaviridae, negative-stranded RNA viruses. Rapid detection (within seconds) of increasing concentrations of viral particles was linear over a range of order of magnitude for both viruses, although the sensor was approximately 5 x 10(5)-fold more sensitive for the detection of SNV. For both pathogens, the sensor's selectivity for its target was not compromised by the presence of confounding Herpes Simplex virus type 1. The biosensor was able to detect SNV at doses lower than the load of virus typically found in a human patient suffering from hantavirus cardiopulmonary syndrome (HCPS). Further, in a proof-of-principle real world application, the SAW biosensor was capable to selectively detect SNV agents in complex solutions, such as naturally occurring bodies of water (river, sewage effluent) without analyte pre-processing. This is the first study that reports on the detection of viral agents using an antibody-based SAW biosensor that has the potential to be used as a hand-held and self-contained device for rapid viral detection in the field.

Bacterial lipopolysaccharide-mediated fetal death. Production of a newly recognized form of inducible cyclooxygenase (COX-2) in murine decidua in response to lipopolysaccharide.

Maternal infection is a cause of spontaneous abortion and preterm labor in humans, but the pathophysiology is unclear. We hypothesized that eicosanoids play an important role in infection-driven pregnancy loss. To investigate this hypothesis, we administered lipopolysaccharide (LPS) to pregnant C3H/HeN mice and found that LPS administration caused fetal death in a dose-dependent fashion. Pretreatment with indomethacin significantly decreased the proportion of fetal death from 83% to < 25% in mice injected with 10 micrograms of LPS. Also, decidual explants from LPS-treated mice produced significantly more inflammatory eicosanoids, including prostaglandins E2 and F2 alpha and thromboxane B2, than controls. We investigated the regulatory mechanisms responsible for increased decidual prostanoid production in response to LPS. Western and Northern blots demonstrated that decidual protein and mRNA levels of a recently recognized highly inducible form of cyclooxygenase, COX-2, were substantially increased in mice treated with LPS. Induction of COX-2 was rapid: mRNA was detected 30 min after LPS injection. In contrast, another form of cyclooxygenase, COX-1, was only minimally induced in response to LPS. Our data indicate that LPS induces decidual prostanoid production via increased COX-2 expression. Since LPS-mediated fetal death is markedly diminished by pretreatment with indomethacin, COX-2-mediated eicosanoid production is likely a key pathophysiologic event in LPS-mediated fetal death.

Antiphospholipid antibodies are directed against epitopes of oxidized phospholipids. Recognition of cardiolipin by monoclonal antibodies to epitopes of oxidized low density lipoprotein.

The optimal clinical management of patients with antiphospholipid antibody syndrome (APS) is uncertain because of a lack of an underlying hypothesis to explain why antiphospholipid autoantibodies (aPL) form to such ubiquitous compounds as phospholipids (PL). In this paper, we demonstrate that many, if not most, aPL are actually directed at neoepitopes of oxidized PL, or neoepitopes generated by adduct formation between breakdown products of oxidized PL and associated proteins. Each cardiolipin (CL) molecule contains four unsaturated fatty acids and is highly susceptible to oxidation, particularly upon exposure to air. Yet, standard anticardiolipin antibodies (aCL) immunoassays routinely bind CL to microtiter wells by evaporation of the ethanol solvent overnight at 4 degrees C. Using a variety of techniques, we demonstrated that rapid oxidation occurs when CL is plated and exposed to air. Sera from apo E-deficient mice, which have high autoantibody titers to oxidized low density lipoprotein, showed a striking time-dependent increase in binding to CL that was exposed to air for increasing periods of time. Monoclonal antibodies to oxidized LDL, cloned from the apo E-deficient mice, also bound to oxidized CL. Both sera and affinity-purified aCL-IgG from APS patients bound to CL progressively as it was oxidized. However, the monoclonal antibodies from apo E-deficient mice, or sera or aCL-IgG from APS patients did not bind to a reduced CL analog that was unable to undergo peroxidation. These data demonstrate that many aPL are directed at neoepitopes of oxidized phospholipids, and suggest that oxidative events may be important in the pathophysiology of APS. In turn, this suggests new therapeutic strategies, possibly including intensive antioxidant therapy.

International consensus statement on an update of the classification criteria for definite antiphospholipid syndrome (APS).

New clinical, laboratory and experimental insights, since the 1999 publication of the Sapporo preliminary classification criteria for antiphospholipid syndrome (APS), had been addressed at a workshop in Sydney, Australia, before the Eleventh International Congress on antiphospholipid antibodies. In this document, we appraise the existing evidence on clinical and laboratory features of APS addressed during the forum. Based on this, we propose amendments to the Sapporo criteria. We also provide definitions on features of APS that were not included in the updated criteria.

Anticardiolipin antibodies from patients with the antiphospholipid antibody syndrome recognize epitopes in both beta(2)-glycoprotein 1 and oxidized low-density lipoprotein.

BACKGROUND: We recently suggested that many anticardiolipin antibodies bind only to oxidized cardiolipin (OxCL) and/or to OxCL-beta(2)-glycoprotein 1 (beta(2)GP1) adducts but not to a "reduced" cardiolipin that is unable to undergo oxidation. To test this hypothesis, we investigated 24 sera, 4 protein A-purified IgG fractions, and 3 human monoclonal antibodies that were all isolated from patients with antiphospholipid antibody syndrome (APS); testing was also performed in 7 controls. Two monoclonal antibodies (IS3 and IS4) were selected for binding to CL and one was selected for binding to beta(2)GP1 (LJB8). METHODS AND RESULTS: By chemiluminescent immunoassay, all APS sera samples bound only to OxCL and not to reduced CL, and the binding was inhibited >95% by OxCL but not reduced CL. All purified IgG fractions bound to beta(2)GP1 but only when the beta(2)GP1 was plated on microtiter wells coated with OxCL. All 3 monoclonal antibodies bound only to OxCL. On Western blots, IS4 and LJB8 bound to beta(2)GP1 as well as to delipidated apoB of oxidized LDL but not to native apoB. IS3 also bound to oxidized apoB on Western blot. Covalent modification of beta(2)GP1 with oxidation products of CL made it more antigenic for APS serum samples, for purified IgG fractions, and for the monoclonal antibodies. CONCLUSIONS: These data support the hypothesis that oxidation of CL is needed to generate epitopes for many anticardiolipin antibodies and that some of these epitopes are covalent adducts of OxCL with beta(2)GP1 or apoB.

Comparative study of 0° X-cut and Y + 36°-cut lithium niobate high-voltage sensing.

A comparison study between Y + 36° and 0° X-cut lithium niobate (LiNbO3) was performed to evaluate the influence of crystal cut on the acoustic propagation to realize a piezoelectric high-voltage sensor. The acoustic time-of-flight for each crystal cut was measured when applying direct current (DC), alternating current (AC), and pulsed voltages. Results show that the voltage-induced shift in the acoustic wave propagation time scaled quadratically with voltage for DC and AC voltages applied to X-cut crystals. For the Y + 36° crystal, the voltage-induced shift scales linearly with DC voltages and quadratically with AC voltages. When applying 5 µs voltage pulses to both crystals, the voltage-induced shift scaled linearly with voltage. For the Y + 36° cut, the voltage-induced shift from applying DC voltages ranged from 10 to 54 ps and 35 to 778 ps for AC voltages at 640 V over the frequency range of 100 Hz-100 kHz. Using the same conditions as the Y + 36° cut, the 0° X-cut crystal sensed a shift of 10-273 ps for DC voltages and 189-813 ps for AC voltage application. For 5 µs voltage pulses, the 0° X-cut crystal sensed a voltage induced shift of 0.250-2 ns and the Y + 36°-cut crystal sensed a time shift of 0.115-1.6 ns. This suggests a frequency sensitive response to voltage where the influence of the crystal cut was not a significant contributor under DC, AC, or pulsed voltage conditions. The measured DC data were compared to a 1-D impedance matrix model where the predicted incremental length changed as a function of voltage. When the voltage source error was eliminated through physical modeling from the uncertainty budget, the combined uncertainty of the sensor (within a 95% confidence interval) decreased to 0.0033% using a Y + 36°-cut crystal and 0.0032% using an X-cut crystal for all the voltage conditions used in this experiment.

The regulation of endothelin production in human umbilical vein endothelial cells: unique inhibitory action of calcium ionophores.

Endothelins (ETs) are a recently discovered family of small proteins that have potent long-lasting vasoconstrictive activities. Increased circulating concentrations of ETs have been found in hypertensive and renal disorders, including pregnancy-induced hypertension (PIH). PIH has been postulated to be the end result of endothelial cell damage and aberrant calcium metabolism. We evaluated the effects of calcium ionophores, calcium channel blockers, and two forms of cellular damage on ET production by human umbilical vein endothelial cells (HUVEC). Cells were grown to confluence and then incubated for 16 h with these treatments: physical trauma ("scratching"), oxidant damage (hydrogen peroxide, 1-20 mM), ionomycin (0.25-2.0 microM), A-23187 (10(-9)-10(-5) M), verapamil (0.22-22.0 microM), and nifedipine (2-200 micrograms/mL). ET production was determined using a commercial RIA that detects ET-1 and ET-2. Physical trauma enhanced ET production, whereas oxidant damage had the opposite effect. Both ionomycin and A-23187 caused concentration-dependent inhibition of ET production. Neither verapamil nor nifedipine consistently altered ET production. We conclude that specific forms of cellular damage can stimulate HUVEC ET production, although oxidant damage may be slightly inhibitory. Thus, enhanced ET levels in PIH may represent endothelial cell activation, rather than damage. HUVEC ET production is regulated in an inverse manner by intracellular calcium concentrations, suggesting a negative feedback from mediators of ET action on cells.

The factor V Leiden mutation which predisposes to thrombosis is not common in patients with antiphospholipid syndrome.

Antiphospholipid syndrome is associated with venous, arterial, and placental thrombosis, possibly through autoantibody impairment of phospholipid-dependent protein C activation. Recently, a missense mutation in the factor V gene (1691 G-->A) has been identified that results in an abnormal factor V product (1). This mutation, known as the Leiden mutation, causes an amino acid substitution of glutamine for arginine at position 506 in the factor V molecule and renders the protein resistant to proteolytic inactivation by activated protein C and thus predisposes to thrombosis (2, 3). We hypothesized that some individuals with antiphospholipid syndrome may also carry the Leiden mutation, and thus have a "second hit" predisposition to thrombosis. To test this hypothesis, allele-specific hybridization and allele-specific restriction analysis were used to test for the Leiden mutation in thirty women with the antiphospholipid syndrome, 10 of whom had a history of thrombosis. None of the women were heterozygous or homozygous for the factor V mutation. We conclude that the presence of the factor V Leiden mutation is not a prerequisite for the thrombotic events in patients with antiphospholipid syndrome, due to the occurrence of thrombosis seen in patients lacking the factor V mutation.

Histologic features of placentas and abortion specimens from women with antiphospholipid and antiphospholipid-like syndromes.

OBJECTIVE: Antiphospholipid syndrome is characterized by recurrent pregnancy loss, thrombosis, and antiphospholipid antibodies. However, some women with clinical features of antiphospholipid syndrome test negative for antiphospholipid antibodies ("antiphospholipid-like syndrome"). Women with antiphospholipid and antiphospholipid-like syndromes have serum immunoglobulin G that harms murine pregnancy, suggesting that the mechanisms of fetal death may be similar in both groups. The objective of our study was to determine whether patients with antiphospholipid and antiphospholipid-like syndromes share pathophysiology by comparing the histology of gestational tissues from these groups. METHODS: Placenta and abortion specimens were obtained from 44 pregnancies in 26 women with antiphospholipid syndrome and 37 pregnancies in 21 women with antiphospholipid-like syndrome. Of these, 16 pregnancies with antiphospholipid syndrome and 8 with antiphospholipid-like syndrome were treated with a variety of medications intended to improve pregnancy outcome. Placentas from 31 elective pregnancy terminations and 40 pregnancies complicated by idiopathic preterm delivery served as an additional control group. Twenty histologic parameters were systematically assessed by a single investigator who was blinded to the clinical status of the specimens. Histopathologic findings were compared among groups using multivariate logistic regression analysis. RESULTS: Antiphospholipid syndrome pregnancies included 15 spontaneous abortions, 13 fetal deaths, and 16 live births. Pregnancies in the antiphospholipid-like syndrome group resulted in 5 spontaneous abortions, 30 fetal deaths, and one live birth. Gestational tissues from antiphospholipid and antiphospholipid-like syndrome pregnancies were similar for every histologic feature tested. Decidua from women with both antiphospholipid and antiphospholipid-like syndromes had more necrosis, acute and chronic inflammation, and vascular thrombus compared to controls. Placental tissue from antiphospholipid and antiphospholipid-like syndrome pregnancies showed more infarction, intravascular fibrin deposition, syncytial knot formation, and fibrosis than controls. Histologic features were variable within groups. There were no histologic differences in tissues from live births and pregnancy losses, or in treated and untreated pregnancies. CONCLUSIONS: Placental histopathology is similar in antiphospholipid and antiphospholipid-like syndrome pregnancies, suggesting that these disorders may share pathophysiology. Histologic findings in women with APS are non-specific and may not differentiate between women with APS and APS-like syndromes.

Long-term stability of grafted polyethylene glycol surfaces for use with microstamped substrates in neuronal cell culture.

Crucial to long-term stability of neuronal micropatterns is functional retention of the underlying substratum while exposed to cell culture conditions. We report on the ability of covalently bound PEG films in long-term cell culture to continually retard protein adhesion and cell growth. PDMS microstamps were used to create poly-d-lysine (PDL) substrates permissive to cell attachment and growth, and polyethylene glycol (PEG) substrates were used to minimize protein and cell adhesion. Film thickness was measured using null ellipsometry and atomic force microscopy (AFM). Organosilane film structure was examined using Fourier transform infrared (FT-IR) spectroscopy. Long-term film stability in cell culture conditions was tested by immersion in 0.1 M sodium phosphate buffer pH 7.4 for up to one month. Null ellipsometry and water contact measurements indicated that organosilane films were stable up to one month, whereas the PEG film thickness declined rapidly after day 25. Hippocampal cells plated at 200 cells/mm2 on uniform PEG substrates gave a steady increase in biofilm thickness on PEG films throughout the culture, possibly from proteins of neuronal origin. We found that all the layers in the cross-linking procedure were stable in cell culture conditions, with the exception of PEG, which degraded after day 25.

Antiphospholipid antibodies and reproductive outcome: the current state of affairs.

Antiphospholipid antibodies were first linked to pregnancy loss more than 20 years ago, and the condition known as antiphospholipid syndrome is perhaps the most convincing 'immunologic' disturbance other than anti-erythrocyte and anti-platelet alloimmunization disorders. Specific criteria for the antiphospholipid syndrome have been delineated, the anticardiolipin assay has been standardized, and authorities agree on laboratory criteria defining lupus anticoagulant. Nonetheless, considerable confusion exists regarding antiphospholipid syndrome and related reproductive problems. The state of affairs primarily derives from two problems: the first is the premature introduction of non-standardized antiphospholipid assays into clinical use without rigorous standardization and prior to convincing proof of clinical utility. As a result, well-intending, but less well-versed clinicians sometimes make the diagnosis of antiphospholipid syndrome in women who are negative for lupus anticoagulant and anticardiolipin antibodies. This is especially confusing in the face of of growing evidence that the relevant in vivo antiphospholipid antigen is formed by a complex between beta 2-glycoprotein 1 and phospholipids. A second major problem is that of unwarranted discrepancies in the clinical and laboratory features of patients considered to have a diagnosis of antiphospholipid syndrome. This problem is most apparent in the case selection for pregnancy-loss treatment series and trials. Many series have included women with predominantly pre-embryonic and embryonic pregnancy losses, while others included a large majority of patients with one or more second or third trimester pregnancy losses. Some treatment trials purposefully excluded patients with a history of thrombosis or systemic lupus erythematosus, features found in nearly 50% of patients in other series. Though most authorities require the presence of either lupus anticoagulant or medium-to-high titer IgG anticardiolipin antibodies to make a diagnosis of antiphospholipid syndrome, in some series no more than half of the study patients had lupus anticoagulant and as many as 20% had only IgM anticardiolipin antibodies. It is very unlikely that patients with such disparate clinical and laboratory findings have the same autoimmune syndrome, and a stated or implicit diagnosis of antiphospholipid syndrome in such a wide variety of women is scientifically unsound and clinically dangerous. The relationship between antiphospholipid antibodies and poor reproductive outcomes must be approached through rigorous scientific study and appropriate treatments established by well-designed clinical trials.