Angiogenic imbalance in pre-eclampsia and fetal growth restriction: enhanced soluble fms-like tyrosine kinase-1 binding or diminished production of placental growth factor?

OBJECTIVES

To assess levels of total placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and free PlGF in women with pre-eclampsia (PE) with or without a small-for-gestational-age (SGA) neonate in order to establish whether low free PlGF levels associated with PE and SGA are due to enhanced sFlt-1 binding or decreased PlGF production.

METHODS

This was a secondary analysis of a prospective multicenter cohort study involving 407 pregnancies with suspected or confirmed PE, in which total PlGF levels were calculated from measured sFlt-1 and free PlGF levels. The control group included women who were suspected to have PE at a certain point in pregnancy but did not develop PE. The analysis was stratified according to whether PE was early- or late-onset (gestational age < 34 weeks vs ≥ 34 weeks) and according to the presence of SGA at birth, which was used as a proxy of fetal growth restriction in the absence of Doppler ultrasound and biometric data.

RESULTS

In early-onset PE, both women with and those without SGA had lower free (19 and 45 pg/mL) and total (44 and 100 pg/mL) PlGF levels compared with women without PE (free and total PlGF, 300 and 381 pg/mL, respectively). SGA alone did not affect free and total PlGF in this condition (free and total PlGF, 264 and 352 pg/mL, respectively). Observations in women with late-onset PE were similar, although the changes were more modest. Both SGA (gestational age < 34 weeks) and PE were individually associated with increased sFlt-1 and, in women with both PE and SGA, the upregulation of sFlt-1 occurred in a synergistic manner, thus resulting in the highest sFlt-1/free PlGF ratio in this group. This occurred in both early- and late-onset PE.

CONCLUSIONS

Particularly in pregnancies with early-onset PE and SGA, diminished PlGF production is an important cause of low free PlGF levels. Under such conditions, sFlt-1 lowering is unlikely to restore the angiogenic balance. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Prediction of pre-eclampsia-related complications in women with suspected or confirmed pre-eclampsia: development and internal validation of clinical prediction model

OBJECTIVE

A model that can predict reliably the risk of pre-eclampsia (PE)-related pregnancy complications does not exist. The aim of this study was to develop and validate internally a clinical prediction model to predict the risk of a composite outcome of PE-related maternal and fetal complications within 7, 14 and 30 days of testing in women with suspected or confirmed PE.

METHODS

The data for this study were derived from a prospective, multicenter, observational cohort study on women with a singleton pregnancy and suspected or confirmed PE at 20 to < 37 weeks' gestation. For the development of the prediction model, the possible contribution of clinical and standard laboratory variables, as well as the biomarkers soluble fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF) and their ratio, in the prediction of a composite outcome of PE-related complications, consisting of maternal and fetal adverse events within 7, 14 and 30 days, was explored using multivariable competing-risks regression analysis. The discriminative ability of the model was assessed using the concordance (c-) statistic. A bootstrap validation procedure with 500 replications was used to correct the estimate of the prediction model performance for optimism and to compute a shrinkage factor for the regression coefficients to correct for overfitting.

RESULTS

Among 384 women with suspected or confirmed PE, 96 (25%) had an adverse PE-related outcome at any time after hospital admission. Important predictors of adverse PE-related outcome included sFlt-1/PlGF ratio, gestational age at the time of biomarker measurement and protein-to-creatinine ratio as continuous variables. The c-statistics (corrected for optimism) for developing a PE-related complication within 7, 14 and 30 days were 0.89, 0.88 and 0.87, respectively. There was limited overfitting, as indicated by a shrinkage factor of 0.91.

CONCLUSIONS

We propose a simple clinical prediction model with good discriminative performance to predict PE-related complications. Determination of its usefulness in clinical practice awaits further investigation and external validation. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Evidence for increased breakthrough rates of SARS-CoV-2 variants of concern in BNT162b2-mRNA-vaccinated individuals

The BNT162b2 mRNA vaccine is highly effective against SARS-CoV-2. However, apprehension exists that variants of concern (VOCs) may evade vaccine protection, due to evidence of reduced neutralization of the VOCs B.1.1.7 and B.1.351 by vaccine sera in laboratory assays. We performed a matched cohort study to examine the distribution of VOCs in infections of BNT162b2 mRNA vaccinees from Clalit Health Services (Israel) using viral genomic sequencing, and hypothesized that if vaccine effectiveness against a VOC is reduced, its proportion among breakthrough cases would be higher than in unvaccinated controls. Analyzing 813 viral genome sequences from nasopharyngeal swabs, we showed that vaccinees who tested positive at least 7 days after the second dose were disproportionally infected with B.1.351, compared with controls. Those who tested positive between 2 weeks after the first dose and 6 days after the second dose were disproportionally infected by B.1.1.7. These findings suggest reduced vaccine effectiveness against both VOCs within particular time windows. Our results emphasize the importance of rigorously tracking viral variants, and of increasing vaccination to prevent the spread of VOCs.

Copeptin and mid-regional pro-atrial natriuretic peptide in women with suspected or confirmed pre-eclampsia: comparison with sFlt-1/PlGF ratio

OBJECTIVES

Arginine vasopressin (AVP) and atrial natriuretic peptide (ANP) may contribute to the pathogenesis of pre-eclampsia (PE), but their role remains to be elucidated. Our aims were to evaluate the surrogates of AVP and ANP, C-terminal pro-AVP (copeptin) and mid-regional pro-ANP (MR-proANP), as biomarkers for the prediction of PE-related pregnancy complications and whether they are associated with angiogenic markers and/or clinical manifestations of PE.

METHODS

This was a retrospective analysis of a prospective cohort study that enrolled pregnant women with suspected or confirmed PE, between December 2013 and April 2016. From each patient, a blood sample was obtained at study entry and serum levels of copeptin, MR-proANP, soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) were measured. We evaluated the ability of sFlt-1, PlGF, sFlt-1/PlGF ratio, copeptin and MR-proANP, assessed either alone or combined with traditional predictors (gestational age, parity, diastolic blood pressure and proteinuria), to predict maternal complications and fetal/neonatal complications. Models were compared using concordance statistic (C-index).

RESULTS

A total of 526 women were evaluated in the study. Women with confirmed PE displayed elevated serum copeptin and MR-proANP levels in comparison to those with suspected PE but no hypertensive disease of pregnancy. When combined with traditional predictors, the sFlt-1/PlGF ratio displayed a higher C-index than copeptin and MR-proANP (0.76, 0.63 and 0.67, respectively, vs 0.60 for the traditional predictors alone) for the prediction of maternal complications. Similarly, for the prediction of fetal/neonatal complications, the sFlt-1/PlGF ratio displayed a higher C-index than copeptin and MR-proANP when added to the traditional model (0.83, 0.79 and 0.80, respectively, vs 0.79 for the traditional predictors alone). When subdividing women according to sFlt-1/PlGF ratio (≥ 85 vs < 85), no differences in copeptin levels were observed, while MR-proANP level was elevated in women with sFlt-1/PlGF ratio ≥ 85. Multiple regression analysis revealed that copeptin and MR-proANP were independent determinants of proteinuria.

CONCLUSIONS

Copeptin and MR-proANP have limited value in predicting PE-related complications when compared with the sFlt-1/PlGF ratio. However, both copeptin and MR-proANP were associated with proteinuria, with copeptin exerting this effect independently of the sFlt-1/PlGF ratio. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Novel plasma biomarkers in arrhythmogenic cardiomyopathy: the role of ST2 and GDF-15 in predicting biventricular involvement

Background

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart muscle disease characterized by fibrofatty replacement of the myocardium and ventricular arrhythmias. Biventricular (BiV) involvement in ARVC may lead to heart failure.

Purpose

This study aimed to investigate the role of novel plasma biomarkers soluble (s)ST2, Galectin-3 (Gal-3) and GDF-15 in predicting BiV involvement and adverse outcomes in ARVC patients.

Methods

ARVC patients from two independent cohorts were studied. 108 patients were included from the discovery cohort and 47 patients were included from a second validation cohort. All patients had a definite ARVC diagnosis at time of blood withdrawal. sST2, Gal-3 and GDF-15 were independently correlated with NT-proBNP, left ventricular (LV) ejection fraction, late gadolinium enhancement by cardiac magnetic resonance (CMR) imaging and clinical outcome.

Results

ARVC patients with LV involvement had higher levels of sST2 and GDF-15 as compared to controls and patients with isolated right ventricular involvement. sST2 and GDF-15 significantly correlated to late gadolinium enhancement on CMR and also correlated to adverse heart failure outcomes. Gal-3 was elevated in ARVC patients with and without LV involvement as compared to controls. The combined use of the three biomarkers (NT-proBNP, sST2 and GDF-15) showed the best performance in predicting LV involvement in both the discovery and the validation cohort. Plasma drawn from coronary arteries and coronary sinus showed a transmyocardial elevation of sST2.

Conclusion

Our study shows that sST2 and GDF-15 may predict BiV involvement and the combined use of NT-proBNP, sST2 and GDF-15 shows the best prediction of LV involvement in ARVC. Transmyocardial elevation of sST2 suggests that this biomarker is produced by myocardial tissue in ARVC.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Fuwai ARVC Program was supported by CAMS Innovation Fund for Medical Sciences and the National Natural Science Foundation of China, Zurich ARVC Program was supported by grants from the Schwyzer Foundation and Baugarten Foundation

Soluble fms-like tyrosine kinase-1 and placental growth factor kinetics during and after pregnancy in women with suspected or confirmed pre-eclampsia

OBJECTIVES

To assess the evolution of the soluble fms-like tyrosine kinase-1 (sFlt-1) to placental growth factor (PlGF) ratio in women with suspected or confirmed pre-eclampsia (PE), and to investigate the changes in sFlt-1 and PlGF levels in pre-eclamptic women after delivery.

METHODS

This was an exploratory study in which secondary analysis was performed on a prospective cohort study that enrolled women with a singleton pregnancy and suspected or confirmed PE from 18 weeks' gestation, carried out between December 2013 and April 2016 at the Department of Obstetrics of the Erasmus Medical Center in Rotterdam. sFlt-1 and PlGF were determined using Roche Diagnostics Elecsys assays in two groups of patients. In the first group, patients with suspected or confirmed PE had sFlt-1 and PlGF levels measured at least twice during their pregnancy. Changes in these biomarkers over the course of pregnancy were compared for patients in this group with a baseline sFlt-1/PlGF ratio of ≤ 38 and for those with a ratio > 38. In the second group, sFlt-1 and PlGF levels of women with PE or HELLP syndrome were measured before and after delivery. For this group, pre- and postpartum sFlt-1 and PlGF levels were compared and half-lives were calculated.

RESULTS

Women with suspected or confirmed PE for whom sFlt-1 and PlGF levels were measured at least twice during pregnancy (n = 46) had a median gestational age at inclusion of 26 weeks (range, 18-40 weeks). In 27 of the 30 patients with sFlt-1/PlGF ratio ≤ 38 at baseline, thereby ruling out PE, the sFlt-1/PlGF ratio remained stable for up to 100 days. In the remaining three patients with a ratio ≤ 38 and in most of the 16 patients with a ratio > 38, the ratio increased further. For women diagnosed with PE or HELLP syndrome for whom sFlt-1 and PlGF levels were measured before and after delivery (n = 26), median gestational age at inclusion was 29 weeks (range, 16-37 weeks) and median time between antepartum measurement and delivery was 2 days (range, 1-17 days). In this group, after delivery, sFlt-1 dropped to < 1% of its pre-delivery value, with a half-life of 1.4 ± 0.3 days, while PlGF dropped to ∼30% of its pre-delivery value, with a half-life of 3.7 ± 4.3 days.

CONCLUSIONS

Based on this small cohort, up to 10% of pregnant women admitted with suspected or confirmed PE presenting with a sFlt-1/PlGF ratio of ≤ 38 display a rise in sFlt-1/PlGF ratio in subsequent weeks, implying that repeat determination of the sFlt-1/PlGF ratio is required to exclude definitively a diagnosis of PE. Furthermore, the rapid and pronounced decline in sFlt-1 levels after delivery in patients with PE/HELLP syndrome suggests that sFlt-1, in contrast to PlGF, is almost entirely derived from the placenta. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Effect of Twice-Yearly Denosumab on Prevention of Bone Mineral Density Loss in De Novo Kidney Transplant Recipients: A Randomized Controlled Trial

We conducted an open-label, prospective, randomized trial to assess the efficacy and safety of RANKL inhibition with denosumab to prevent the loss of bone mineral density (BMD) in the first year after kidney transplantation. Ninety kidney transplant recipients were randomized 1:1 2 weeks after surgery to receive denosumab (60 mg at baseline and 6 months) or no treatment. After 12 months, total lumbar spine areal BMD (aBMD) increased by 4.6% (95% confidence interval [CI] 3.3-5.9%) in 46 patients in the denosumab group and decreased by -0.5% (95% CI -1.8% to 0.9%) in 44 patients in the control group (between-group difference 5.1% [95% CI 3.1-7.0%], p < 0.0001). Denosumab also increased aBMD at the total hip by 1.9% (95% CI, 0.1-3.7%; p = 0.035) over that in the control group at 12 months. High-resolution peripheral quantitative computed tomography in a subgroup of 24 patients showed that denosumab increased volumetric BMD at the distal tibia and radius (all p < 0.05). Biomarkers of bone turnover (C-terminal telopeptide of type I collagen, procollagen type I N-terminal propeptide) markedly decreased with denosumab (all p < 0.0001). Episodes of cystitis and asymptomatic hypocalcemia occurred more often with denosumab, whereas graft function, rate of rejections, and incidence of opportunistic infections were similar. In conclusion, denosumab increased BMD in the first year after kidney transplantation but was associated with more frequent episodes of urinary tract infection.

Trophoblast invasion: assessment of cellular models using gene expression signatures

Invasive, extravillous trophoblasts (EVT) of the human placenta are critically involved in successful pregnancy outcome since they remodel the uterine spiral arteries to increase blood flow and oxygen delivery to the placenta and the developing fetus. To gain more insights into their biological role different primary cell culture models are commonly utilised. However, access to early placental tissue may be limited and primary trophoblasts rapidly cease proliferation in vitro impairing genetic manipulation. Hence, trophoblastic cell lines have been widely used as surrogates to study EVT function. Although the cell lines share some molecular markers with their primary counterpart, it is unknown to what extent they recapitulate the invasive phenotype of EVT. Therefore, we here report the first thorough GeneChip analyses of SGHPL-5, HTR-8/SVneo, BeWo, JEG-3 and the novel ACH-3P trophoblast cells in comparison to previously analysed primary villous cytotrophoblasts (CTBs) and extravillous trophoblasts (EVTs). Analyses of approximately 14,000 commonly expressed genes revealed that EVTs most closely resemble CTBs with considerable differences to the group of choriocarcinoma cells (JEG-3, BeWo, ACH-3P) and the group of SV40 Large T Antigen-selected cell types (SGHPL-5, HTR-8/SVneo). Similarly, analyses of 912 genes discriminating EVT from CTB, or 370 EVT-specific genes did not unravel a particular cell line with close similarity to any of the primary cell types, although molecular signatures common to EVT and each group of cell lines could be identified. Considering the diversity of mRNA expression patterns it is suggested that molecular studies in trophoblast cell lines require verification of the critical steps in an appropriate primary model system.

A worldwide multicentre comparison of assays for cerebrospinal fluid biomarkers in Alzheimer's disease

BACKGROUND

Different cerebrospinal fluid (CSF) amyloid-beta 1-42 (Abeta(1-42)), total Tau (Tau) and Tau phosphorylated at threonine 181 (P-Tau) levels are reported, but currently there is a lack of quality control programmes. The aim of this study was to compare the measurements of these CSF biomarkers, between and within centres.

METHODS

Three CSF-pool samples were distributed to 13 laboratories in 2004 and the same samples were again distributed to 18 laboratories in 2008. In 2004 six laboratories measured Abeta(1-42), Tau and P-Tau and seven laboratories measured one or two of these marker(s) by enzyme-linked immunosorbent assays (ELISAs). In 2008, 12 laboratories measured all three markers, three laboratories measured one or two marker(s) by ELISAs and three laboratories measured the markers by Luminex.

RESULTS

In 2004, the ELISA intercentre coefficients of variance (interCV) were 31%, 21% and 13% for Abeta(1-42), Tau and P-Tau, respectively. These were 37%, 16% and 15%, respectively, in 2008. When we restricted the analysis to the Innotest (N = 13) for Abeta(1-42), lower interCV were calculated (22%). The centres that participated in both years (N = 9) showed interCVs of 21%, 15% and 9% and intra-centre coefficients (intraCV) of variance of 25%,18% and 7% in 2008.

CONCLUSIONS

The highest variability was found for Abeta(1-42). The variabilities for Tau and P-Tau were lower in both years. The centres that participated in both years showed a high intraCV comparable to their interCV, indicating that there is not only a high variation between but also within centres. Besides a uniform standardization of (pre)analytical procedures, the same assay should be used to decrease the inter/intracentre variation.

Human chorionic gonadotrophin attenuates NF-kappaB activation and cytokine expression of endometriotic stromal cells

Recently, a clinical study provided evidence that treatment of endometriotic women with human chorionic gonadotrophin (hCG) alleviates disease-related pain and sleeplessness suggesting therapeutic effects of the hormone. Since endometriosis is associated with aberrant concentrations of inflammatory mediators in the peritoneal fluid, we investigated whether hCG may affect cytokine-dependent activation of the key-regulatory transcription factor NF-kappaB and expression of two nuclear factor kappa B (NF-kappaB)-inducible genes, tumour necrosing factor (TNF-alpha) and interleukin (IL)-1beta, in stromal cells isolated from ectopic endometriotic tissues. Electrophoretic mobility shift assay revealed that treatment of these cultures with the urinary preparation hCG-A suppressed TNF-alpha- or IL-1beta-induced NF-kappaB DNA-binding activity, whereas another urinary hCG preparation (hCG-B) was less effective. Recombinant alphahCG or epidermal growth factor (EGF), a contaminant of some urinary hCG preparations, did not alter cytokine-dependent NF-kappaB activation. Immunofluorescene of its p65 subunit revealed that pre-incubation with hCG-A strongly decreased TNF-alpha-dependent nuclear expression of NF-kappaB. Accordingly, hCG-A diminished IL-1beta-induced TNF-alpha transcript levels and protein release measured by quantitative real-time PCR and enzyme-linked immunosorbent assay. The hormone also attenuated TNF-alpha-dependent mRNA expression of IL-1beta. Western blot analyses revealed that hCG-A impaired TNF-alpha-mediated phosphorylation and degradation of the inhibitor IkappaBalpha suggesting that the hormone may reduce nuclear import of NF-kappaB by stabilizing its inhibitor. The data suggest that hCG attenuates inflammation-dependent NF-kappaB activation and cytokine expression that could provide one explanation for the beneficial role of the hormone in endometriotic patients.

Effects of Different Human Chorionic Gonadotrophin Preparations on Trophoblast Differentiation

Recent evidence from the literature suggested that hCG preparations purified from urine of pregnant women, which are widely used in in vitro studies and IVF programs, may contain contaminants such as EGF. To determine the putative biological effects of the contaminating growth factor, we here investigated distinct trophoblast differentiation processes in the presence of various hCG compounds. Western blot analyses indicated that treatment of trophoblastic SGHPL-5 cells and purified term trophoblasts with potentially EGF-contaminated hCG (hCG-A) resulted in auto-phosphorylation of the EGF receptor at tyrosine 1173 whereas supplementation of another urine-purified hCG preparation (hCG-B), recombinant holo-hCG or recombinant alphahCG had no effects. Phosphorylation was specifically blocked by the EGF receptor inhibitor PD153035. Urinary hCG-A was most effective in promoting invasion of SGHPL-5 cells through Matrigel-coated transwells, but increased invasiveness was also observed in the presence of hCG-B or recombinant holo-hCG. Similarly, the extent of syncytialisation of term trophoblasts, quantitated by nuclei in desmoplakin-negative areas, was highest upon addition of hCG-A or recombinant EGF as a control. PD153035 reduced invasion and fusion of trophoblasts supplemented with hCG-A, but did not diminish the effects provoked by hCG-B. In conclusion, the data suggest that the EGF contamination of hCG considerably affects trophoblast function. Experiments using EGF-free hCG preparations demonstrate that the hormone increases trophoblast invasion and syncytialisation.

Tumour necrosis factor-alpha impairs chorionic gonadotrophin beta-subunit expression and cell fusion of human villous cytotrophoblast

Growth factors expressed at the fetal-maternal interface modulate hormone expression of placental trophoblasts. The aim of this study was to investigate the effects of different cytokines on hCG subunit mRNA expression in differentiating villous cytotrophoblasts. Quantitative real-time PCR revealed a 1.8- and 6.9-fold increase of hCG-alpha and hCG-beta mRNA levels, respectively, between 36 and 60 h of term trophoblast syncytialization. Compared with controls, neither interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-10, IL-13 and IL-15 nor tumour necrosis factor (TNF)-alpha significantly altered hCG-alpha mRNA expression. Similarly, the ILs did not affect hCG-beta transcript levels. In contrast, TNF-alpha suppressed hCG-beta mRNA 3.8- and 1.8-fold at 36 and 60 h of term trophoblast differentiation. Accordingly, hCG secretion was impaired by TNF-alpha but not by the different ILs. Moreover, TNF-alpha reduced luciferase expression of reporter plasmids harbouring the proximal hCG-beta5 promoter to 35 and 77%, respectively, in primary term trophoblasts and trophoblastic SHGPL-5 cells. In addition, counting of nuclei in syncytialized, desmoplakin-negative areas revealed a 1.9-fold reduction of term trophoblast fusion in the presence of TNF-alpha. Similarly, floating explant cultures prepared from first trimester-denuded villi recovered the syncytium 2.8-fold less efficiently during 72 h of cytokine treatment. Concomitantly, TNF-alpha impaired induction of endogenous and secreted hCG-beta protein levels in these cultures. The data suggest that TNF-alpha decreases hCG-beta mRNA and protein expression by reducing gene transcription and trophoblast cell fusion. Suppression of these processes by TNF-alpha could partly explain the adverse effects of the cytokine on placental function and pregnancy outcome.

TNFalpha-mediated induction of PAI-1 restricts invasion of HTR-8/SVneo trophoblast cells

The pro-inflammatory cytokine TNFalpha has numerous effects on placental trophoblasts. Here, we investigated the effects of the cytokine on gene expression and function of the extravillous trophoblast cell line HTR-8/SVneo. Wound healing and Matrigel invasion assays demonstrate that TNFalpha impairs motility and invasiveness. In contrast, counting of cumulative cell numbers and FACS analyses revealed that the cytokine did neither affect proliferation nor distribution of cell cycle phases. Immunocytochemistry of the cytokeratin 18 neo-epitope suggests that TNFalpha did not induce apoptosis in HTR-8/SVneo cells. Gelatine zymography and enzyme activity assays of supernatants of TNFalpha-treated cells demonstrate elevation of the pro- and active form of MMP-9 suggesting that increased expression of the protease cannot overcome the TNFalpha-inhibitory effect on cell invasion. Semi-quantitative RT-PCR analyses suggest that the cytokine may not alter mRNA levels of uPA and tPA. However, elevated expression of PAI-1 was detected by RT-PCR, as well as by Northern and Western blot analyses. Supplementation of PAI-1-blocking antibodies restored invasion of TNF-alpha-incubated HTR-8/SVneo cells through Matrigel-coated transwells. In addition, immunocytochemistry revealed nuclear accumulation of the p65 subunit of NFkappaB in the presence of the cytokine. EMSA indicated TNFalpha-induced binding of the inflammatory transcription factor to an NFkappaB consensus sequence and to the NFkappaB recognition site located in the PAI-1 promoter. The data suggest that TNFalpha restricts trophoblast invasion mainly by increasing the expression of PAI-1. Induction of the inhibitor may involve TNFalpha-stimulated activation of NFkappaB.

Production of pro- and anti-inflammatory cytokines of human placental trophoblasts in response to pathogenic bacteria

OBJECTIVE

We studied the production of cytokines in purified cultures of human term trophoblasts in the presence of pathogenic strains of Escherichia coli, Bacteroides fragilis, Mycoplasma hominis, Staphylococcus aureus, and Streptococcus agalactiae, which have been identified in intrauterine infections.

METHODS

Human villous trophoblasts were isolated from term placentas after cesarean section and purified by several steps. After 6, 12, and 24 hours of incubation with the different heat-inactivated bacteria, interleukin-1beta (IL-1beta), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-10 (IL-10) as well as tumor necrosis factor-alpha (TNF-alpha) were measured from supernatants by commercially available enzyme-linked immunosorbent assay. Expression of cytokine mRNAs was determined by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTS

In nonstimulated cultures, low (IL-1beta and TNF-alpha) and high (IL-6, IL-8, and IL-10) basal secretion of cytokines was detectable. The pathogenic microorganisms induced a dose- and time-dependent release of IL-1beta, IL-6, IL-8, and IL-10, whereas TNF-alpha secretion was not elevated. E coli was the most potent inducer followed by B fragilis, S agalactiae, S aureus, and M hominis. Transcripts encoding IL-1beta, IL-6, IL-8, or IL-10 were elevated in the RT-PCR reactions, suggesting that transcriptional mechanisms contribute to elevated cytokine expression.

CONCLUSION

Pathogenic microorganisms stimulated mRNA expression and polypeptide release of pro- and anti-inflammatory cytokines from placental trophoblasts. Induction of both inflammation-promoting and inflammation-inhibiting cytokines by bacterial products could play a role in modulating the inflammatory response associated with chorioamnionitis.

The Knee Society Index of Severity for failed total knee arthroplasty: practical application

Previous classifications of severity for total knee arthroplasty revisions have been based largely on bone loss of the femur and tibia. These approaches failed to address the more technically difficult issues in revision surgery such as surgical exposure, contractures, extremity alignment, implant removal, soft tissue stability (in the anteroposterior and in the sagittal planes), extensor mechanism integrity, and patellar revisability. Through the Knee Society, the authors developed a severity index that incorporated these latter factors into one measure. The current authors describe the application of the Knee Society Index of Severity for failed total knee arthroplasty and its method of scoring.

The Knee Society Index of Severity for failed total knee arthroplasty: development and validation

Compared with primary knee replacement, total knee arthroplasty revision surgery is a more complex procedure and accounts for greater expenditures of healthcare resources at each clinical stage. Overall, patients having revision procedures have poorer functional outcomes and higher complication rates than patients having primary arthroplasty. Despite the expanded scope of revision problems and the rapidly emerging technology in revision surgery, the long-term success of any method remains in question. Because there is little consensus on the timing of revision surgery, optimal surgical reconstruction, and the type of prosthesis to be implanted, the Knee Society began development of an Index of Severity for Failed Total Knee Arthroplasty. Fifty-four percent of Knee Society members completed an 82-item questionnaire that determined their clinical impression about potential risk factors for the outcomes of revision surgery for failed total knee replacements. Using these results, a consensus group developed the final version of the index. The result of the nominal group process was the Knee Society Index of Severity, which was based on eight distinct domains. Each domain was divided into attributes and weights based on the questionnaire responses and consensus meeting. Actual case scenarios from five institutions were used to test interrater reliability and validity. The interrater reliability of the average score of all ratings was 0.95; the correlation of the criterion rating with the mean rating was 0.77. When three outliers were not included, the Pearson product correlation increased to 0.92. These data support the application of the Knee Society Index of Severity as a critical component of risk factor studies, effectiveness research, and cost-effectiveness analysis involving revisions of total knee replacements.

Reliability and intraoperative validity of preoperative assessment of standardized plain radiographs in predicting bone loss at revision hip surgery

BACKGROUND

The most challenging aspect of revision hip surgery is the management of bone loss. A reliable and valid measure of bone loss is important since it will aid in future studies of hip revisions and in preoperative planning. We developed a measure of femoral and acetabular bone loss associated with failed total hip arthroplasty. The purpose of the present study was to measure the reliability and the intraoperative validity of this measure and to determine how it may be useful in preoperative planning.

METHODS

From July 1997 to December 1998, forty-five consecutive patients with a failed hip prosthesis in need of revision surgery were prospectively followed. Three general orthopaedic surgeons were taught the radiographic classification system, and two of them classified standardized preoperative anteroposterior and lateral hip radiographs with use of the system. Interobserver testing was carried out in a blinded fashion. These results were then compared with the intraoperative findings of the third surgeon, who was blinded to the preoperative ratings. Kappa statistics (unweighted and weighted) were used to assess correlation. Interobserver reliability was assessed by examining the agreement between the two preoperative raters. Prognostic validity was assessed by examining the agreement between the assessment by either Rater 1 or Rater 2 and the intraoperative assessment (reference standard).

RESULTS

With regard to the assessments of both the femur and the acetabulum, there was significant agreement (p < 0.0001) between the preoperative raters (reliability), with weighted kappa values of >0.75. There was also significant agreement (p < 0.0001) between each rater's assessment and the intraoperative assessment (validity) of both the femur and the acetabulum, with weighted kappa values of >0.75.

CONCLUSIONS

With use of the newly developed classification system, preoperative radiographs are reliable and valid for assessment of the severity of bone loss that will be found intraoperatively.

Revision total hip arthroplasty with the use of structural acetabular allograft and reconstruction ring: a case series with a 10-year average follow-up

From 1980 through 1993, 20 consecutive massive structural acetabular allografts and reconstruction rings were performed in 19 patients. In all cases, the magnitude of the acetabular bone deficiency was such that the allograft supported >50% of the cup. The allograft was necessary to restore normal anatomy, bone stock, and leg length. Of the 19 patients who met the inclusion criteria, 7 subjects died of unrelated causes, and 3 subjects failed and underwent resection arthroplasty, 1 (8%) for graft resorption and 2 (15%) for recurrent dislocation. The remaining 9 patients (10 allografts) had a minimum follow-up of 5 years and average follow-up of 10.5 years. The cohort was analyzed using radiographic and outcome data collection questionnaires (AAOS/HKOD, WOMAC, SF-36). The study supports the use of massive structural allografts and reconstruction rings and achieves satisfactory results in 77% (10 of 13) of the patients. We believe these results reveal an impressive outcome for what used to be thought of as a salvage operation.

Promoter elements and transcription factors involved in differentiation-dependent human chorionic gonadotrophin-alpha messenger ribonucleic acid expression of term villous trophoblasts

Differentiation of primary villous cytotrophoblasts into syncytia is associated with increasing production of alpha and beta human CG subunits, which is predominantly governed at the level of messenger RNA expression. Here, we present a detailed study on the mechanisms involved in the differentiation-dependent regulation of the trophoblast-specific CGalpha gene promoter. Site-directed mutations in each of the five DNA-elements of the composite enhancer were performed to investigate the contribution of the individual regulatory sequences to the overall transcriptional activity of the promoter at two different stages of trophoblast in vitro differentiation. We show that deletion of one cyclic AMP response element (CRE) did not affect CGalpha promoter activity in cytotrophoblasts; however, it reduced transcription by 33% in differentiating cultures. Removal of both CREs almost abolished transcription at early and later stages of in vitro differentiation. Upon mutation the enhancer elements alphaACT, JRE, and CCAAT significantly decreased luciferase reporter transcription; however their contribution to the total promoter activity did not change during in vitro differentiation. Contrary to that, mutated TSE diminished promoter activity by 19% during 12 and 48 h of cultivation but reduced luciferase expression by 78% between 48 and 84 h of differentiation. In electrophoretic mobility shift assay, the TSE interacted with activating protein (AP)-2alpha in both primary trophoblasts and choriocarcinoma cells. While CRE-interacting proteins were detectable 12 h after isolation, the TSE-binding complex did not appear before 36 h of in vitro differentiation. During syncytium formation increasing protein expression of activating transcription factor (ATF)-1, cAMP response element-binding protein (CREB)-1, and AP-2alpha was observed on Western blots. Moreover, phosphorylated CREB-1 and ATF-1 accumulated between 24 and 78 h of trophoblast cultivation. By fluorescence immunohistochemistry, we show that CREB-1 was predominantly expressed in syncytiotrophoblasts, whereas ATF-1 and AP-2alpha localized to the syncytium and some cytototrophoblasts as well as to stromal and endothelial cells of the placental villus. Phosphorylated CREB-1/ATF-1 and the coactivator protein CBP were primarily detected in syncytial nuclei, suggesting the presence of functional, cAMP-dependent transcriptional complexes in the differentiated tissue. In agreement to the in vivo situation, phosphorylated CREB-1/ATF-1 were observed in nuclei of the differentiated trophoblast cultures. The activity of the CGalpha promoter as well as CREB-1/ATF-1 phosphorylation increased upon elevation of cAMP levels and overexpression of the catalytic subunit of protein kinase A. Additionally, we demonstrate that overproduction of the enzyme enhanced protein expression and binding of AP-2alpha to the TSE. We conclude that differentiation-dependent transcription of the CGalpha gene in villous trophoblasts is mainly governed by increasing expression of AP-2alpha and PKA-dependent phosphorylation of CREB-1 and ATF-1.

Understanding economic evaluations: a review of the knee arthroplasty literature

The study reviewed the literature to appraise the quality, quantity, and type of economic evaluation as it pertains to the knee arthroplasty literature. A computerized bibliographic search of MEDLINE from 1966-1996 was conducted, revealing a total of 43,178 articles dealing with cost analysis, of which 1611 were orthopedic. Of the economic orthopedic studies, only 63 dealt with the topic of knee arthroplasty. These studies were retrieved, of which only 40 papers met the inclusion criteria. These 40 studies were evaluated for methodological soundness based on established economic principles. None of the 40 studies met the established criteria to form a comprehensive economic evaluation. These results indicate that the orthopedic literature is lacking in economically sound evaluations, and guidelines are offered to aid orthopedists in appraising and improving the quality of economic studies.

Economic evaluations in the hip arthroplasty literature: lessons to be learned

Readers are increasingly encountering articles dealing with health economic evaluations that compare various surgical strategies, leaving orthopaedists with the challenge of determining which program is cost-efficient and truly pertains to their setting. This study carries out a systematic review of the literature to appraise the quality, quantity, and type of economic evaluation as it pertains to the hip arthroplasty literature. To identify all relevant articles, we conducted a comprehensive computerized bibliographic search of Medline from 1966 to 1996. This search produced 1,611 abstracts that were screened. Studies that were incorporated met the following inclusion criteria: i) formal economic analysis, ii) an intervention specific to hip arthroplasty, and iii) the perspective of the study was evident (ie, patient, provider, society). These studies were appraised with regards to methodologic soundness based on 8 established economic principles. Only 68 articles from the 138 retrieved met the study criteria. Only 2 of the 68 articles met all 8 criteria of a comprehensive economic evaluation. The hip arthroplasty literature is deficient in methodologically sound economic evaluations. Several guidelines are introduced to aid orthopaedists in appraising the various economic studies, and recommendations are made to improve the quality of these studies in the orthopaedic literature. We suggest that the generation of such information should rank high on the priority list of the orthopaedic profession, granting agencies, and governments.

Cyclic AMP- and differentiation-dependent regulation of the proximal alphaHCG gene promoter in term villous trophoblasts

Although the regulatory mechanisms controlling alpha and beta human chorionic gonadotrophin (HCG) expression have been investigated in choriocarcinoma cell model systems, little is known about the regulation of HCG subunit synthesis in non-tumourigenic trophoblasts. We therefore investigated alphaHCG mRNA transcription in villous cytotrophoblasts isolated from term placentae and have shown for the first time that the proximal alphaHCG gene promoter is functional in these cells. By establishing conditions which allow efficient transient transfection of immunopurified cells, we have demonstrated that a 363 bp sequence in the proximal 5' flanking region of the alphaHCG gene is sufficient to direct trophoblast-specific expression of a luciferase reporter. After 12-60 h cultivation, an increase in endogenous alphaHCG mRNA expression could be detected, indicating that aggregated villous trophoblasts undergo biochemical differentiation. Concomitantly, we observed induction of alphaHCG promoter-driven luciferase activity, suggesting that the 363 bp sequence of the proximal 5' flanking region is sufficient to direct differentiation-dependent increase of alphaHCG mRNA. Continuous luciferase expression required functional cAMP-response elements (CREs), since deletion of both recognition sequences eliminated differentiation-dependent transcription of the reporter. Elevation of cAMP values increased transcription of the wild-type construct; however, it did not affect promoter activity of the mutant plasmid. Moreover, we have demonstrated that during in-vitro differentiation, CREs interacted with increasing amounts of phosphorylated activating transcription factor/cyclic AMP response element-binding protein (ATF-1/CREB-1) suggesting that these cAMP-dependent DNA-binding factors are major determinants in regulating alphaHCG gene expression in villous trophoblasts.

Study of the role of parvo virus B19 in arthropathies of Egyptian adult cases

This work was done to assess the relation between HPV B19 infection and arthropathies in Egyptian adults cases. For this purpose 40 rheumatoid arthritis (RA) cases, 10 osteoarthritis cases and 10 systemic lupus erythematosus (SLE) cases were selected to represent different types of arthropathies. The selection of cases was based on clinical diagnosis and laboratory tests (ESR, Hb level, Rose waller, detection of antinuclear antibodies and detection of hidden rheumatoid factor). HPV B19 IgM and IgG were searched for by ELISA test in their sera as indicator of the state of HPV B19 infection. A control group was also included in this study, as 30 healthy persons with no previous complaint of rheumatic symptoms. HPV B19 IgM was detected in 60% of patients with RA, 40% of osteoarthritis cases and None of the SLE cases. Positive cases were more among females with long duration of illness affecting both big and small joints. These results indicated a possible causal association between acute HPV B19 and arthropathy. As regards HPV B19 IgG, it was detected in 57% of RA cases, 60% of osteoarthritis cases and 40% of SLE. The difference in IgG was statistically insignificant from the control group (46.7%). The presence of HPV B19 IgG antibodies indicates previous exposure to the virus but does not indicate its time. Detection of HPV B19 IgM or rising titer of HPV B19 IgG may lead to early diagnosis of HPV B19 arthropathies.

Special matrix for use with glass ionomer in restoring molars with Class V root surface lesions

A simple method of making a custom matrix for molar root lesions has been described. The matrix provides anatomic form to the restoration and reduces the chairside time required to contour and finish the restoration.

Effects of thyroid state alterations in ovo on the plasma levels of thyroid hormones and on the populations of fibers in the plantaris muscle of male and female chickens

Propylthiouracil (PTU), thyroxine (T4) or thyreoliberin (TRH) were injected in ovo to modify the thyroid state of chicken embryos. Significant sexual differences were observed in the effects of these treatments on the plasma concentrations of thyroid hormones and on plantaris muscle characteristics (DNA, RNA, populations of muscle fibers) in 3- and 35-day old male and female chickens. The T4 plasma concentration is lower in control males; it is decreased in PTU treated females and in the T4 treated females at 35 days. The T3 plasma concentration is lowered at 3 days in all treated chickens and also at 35 days in the TRH treated animals. The slow (STnO) and the fast (FTOG) fibers of the plantaris are always more numerous in males. In controls, the number of FTOG fibers remains steady between 3 and 35 days; at the same time, the number of STnO fibers rises in males only. Both PTU and T4 treatments increase the number of the FTOG and the STnO fibers respectively before and after the 3rd day. TRH treatment increases the number of STnO fibers at 3 and 35 days in males, but reduces it at 3 days in females. Thus changes in the number of FTOG fibers can be induced during in ovo myogenesis, whereas the number of STnO fibers may increase after hatching.

Clinical behavior of silver-palladium alloy castings: a five-year comparative clinical study

A 5-year clinical comparison between silver palladium alloys (Albacast and Ney 76) and gold alloy (Firmilay) was conducted. Clinical evaluations for the castings of these materials placed in the same patients, were recorded immediately after cementation, at 3 months, 6 months, 1.5 years, 3 years, and 5 years. The changes in surface tarnish, discoloration, polish, and plaque accumulation was compared. The results indicated that gold alloys responded slightly better than Ney 76 alloy, but similar to Albacast alloy with adequate correlation between the four criteria evaluated.