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Stanniocalcin‐1 (STC‐1) is a multi‐functional glycosylated peptide present in the plasma of healthy women postpartum and increased further in pregnancies complicated by preeclampsia. Although the STC‐1 gene is expressed by the placenta what regulates its secretion and from which cells at the feto‐maternal interface is unknown. Here, we demonstrate for the first time that the syncytiotrophoblast and cytotrophoblast are a major site of STC‐1 protein expression in first trimester placental tissue. Further, in response to low oxygen, first trimester chorionic villous tissue from pregnancies at increased risk of developing preeclampsia secreted significantly more STC‐1 than normal tissue under the same conditions. Using the human trophoblast cell line BeWo we have shown that low oxygen increased the secretion of STC‐1 but it required co‐stimulation with the Adenosine‐3', 5'‐cyclic monophosphate (cAMP) analogue, 8‐Bromo adenosine‐3', 5'‐cyclic monophosphate cAMP (8 Br‐cAMP) to reach significance. Inhibition of Hypoxia inducible factor 2α (HIF‐2α) and the Phosphatidylinositol‐3 kinase (PI3‐Kinase)/AKT/Serum and glucocorticoid‐induced kinase‐1(SGK‐1) pathway resulted in significant inhibition of STC‐1 secretion. As both low oxygen and cAMP are known to play a central role in placental function, their regulation of STC‐1 points to a potentially important role in the maintenance of a normal healthy pregnancy and we would hypothesize that it may act to protect against prolonged placental hypoxia seen in preeclampsia.

Introduction: Covid-19 (CV19) infection is associated with pulmonary embolism (PE). We sought to detail the presence of PE, clinical, laboratory features, and outcomes of those with PE and CV19 compared to CV19 and no PE. Methods: Retrospective analysis of all computed tomography pulmonary angiogram (CTPA) studies undertaken at our hospital during the peak of the pandemic between 29/2-3/5/2020. We included all inpatients with positive CV19 swab or classical or probable features of CV19 on CTPA. All CTPAs were reviewed by certified radiologists. The patient's electronic health records were reviewed for clinical data. Results: Total 132 (45.9%) of CTPAs met inclusion criteria. Presence of PE was 31 (23.5%), with 13 (41.9%) being central, and 18 (58.1%) peripheral. Men (70.4%, P0.04) and white ethnicity (58.1%, P0.03) were significantly associated with PE. No association was seen between CTPA radiographic severity of CV19 and presence of PE. Thromboprophylaxis was administered to 73.2% of the cohort prior to CTPA, no association (P0.29) between administration and diagnosed PE. No difference in vital observations in the 24hrs prior to CTPA as detected. Median Ddimer and Troponin T were significantly elevated (P

Various studies found an association of different renin-angiotensin system (RAS) components with gestational duration and preterm birth, as well as with preeclampsia. Approximately 25% of first-time pregnant women develop a mild to severe hypertension in pregnancy or even preeclampsia. Based on recently published single-cell RNA-sequencing, we hypothesized an alternative RAS function in placenta and furthermore, an implication in hypertensive disorders in pregnancy. Placental RAS expression and localization was analyzed via quantitative polymerase chain reaction and in situ mRNA padlock probes. Tissue was collected from first-trimester elective termination (n=198), from healthy third-trimester controls (n=54), from early-onset preeclamptic (n=54) and age-matched controls (n=29), as well as first-trimester placentae from women with a high uterine artery resistance index (high-risk for preeclampsia, n=9) and controls (n=8). Serum levels of Ang (angiotensin) I to IV from women before and after conception were measured via mass spectrometry (n=10). Placental explants were cultured in 2.5% oxygen with Ang II, candesartan, and leptin. Seahorse XF96 MitoStress assays assessed trophoblast metabolism. Here, we show that maternal angiotensin acts on placental LNPEP (leucine aminopeptidase), that is, angiotensin IV-receptor and fetal angiotensin on placental AGTR1 (angiotensin II receptor type 1). Maternal circulating RAS shifts towards Ang IV in pregnancy. Ang IV decreases trophoblastic mitochondrial respiration and increases placental leptin via placental LNPEP. Lower placental LNPEP in preeclampsia and in first-trimester patients at high-risk for preeclampsia suggests a new alternative route in maternal RAS signaling and may contribute to hypertension and disease in pregnancy. The study shows how hypertensive disorders in pregnancy may be connected metabolic alterations that finally seem to contribute to the multifactorial disease in pregnancy, preeclampsia.

Transformation of the uterine spiral arteries (SAs) during pregnancy is critical to support the developing fetus, and is impaired in some pregnancy disorders, including preeclampsia. Decidual natural killer (dNK) cells play a role in SA remodeling, although their interactions with fetal trophoblast remain unclear. A uterine artery Doppler resistance index (RI) in the first trimester of pregnancy can be used as a proxy measure of the extent of SA remodeling; we have used this technique to characterize dNK cells from pregnancies with normal (normal RI) and impaired (high RI) SA remodeling, which display least and highest risk of developing preeclampsia, respectively. We examined the impact of dNK cell secreted factors on trophoblast motility, chemoattraction, and signaling pathways to determine the contribution of dNK cells to SA transformation. We demonstrated that the chemoattraction of the trophoblast by dNK cells is impaired in pregnancies with high RI, as is the ability to induce trophoblast outgrowth from placental villous explants. These processes are dependent on activation of the extracellular signal–regulated kinase 1/2 and phosphatidylinositol 3-kinase–Akt signaling pathways, which were altered in trophoblasts incubated with secreted factors from dNK cells from high RI pregnancies. Therefore, by characterizing pregnancies using uterine artery Doppler RI before dNK cell isolation, we have identified that impaired dNK-trophoblast interactions may lead to poor placentation. These findings have implications for pregnancy pathological conditions, such as preeclampsia.

Background Information. Tumour cells can be induced to undergo apoptosis after treatment with the tumour necrosis factor -related death-inducing ligand (TRAIL). Although human pancreatic cancer cells show varying degrees of response they can be sensitised to the pro-apoptotic effects of TRAIL in the presence of celastrol, a natural compound extracted from the plant Tripterygium wilfordii Hook F. One important aspect of the cellular response to TRAIL is the control of protein synthesis, a key regulator of which is the eukaryotic initiation factor 4E-binding protein, 4E-BP1. Results. We examined the effects of celastrol and TRAIL in several pancreatic cancer cell lines. In cells that are normally resistant to TRAIL, synergistic effects of TRAIL plus celastrol on commitment to apoptosis and inhibition of protein synthesis were observed. These were associated with a strong up-regulation and dephosphorylation of 4E-BP1. The enhancement of 4E-BP1 expression, which correlated with a threefold increase in the level of the 4E-BP1 transcript, was blocked by inhibitors of reactive oxygen species and the JNK protein kinase. When the expression of 4E-BP1 was reduced by an inducible micro-RNA, TRAIL-mediated apoptosis was inhibited. Conclusion. These results suggest that 4E-BP1 plays a critical role in the mechanism by which TRAIL and celastrol together cause apoptotic cell death in human pancreatic tumour cells.

Aims In early human pregnancy placental trophoblasts migrate along uterine spiral arteries (SAs) and remodel these vessels into wide-bore conduits in a process essential for successful pregnancy. Until 10–12 weeks gestation trophoblasts plug spiral arteries, resulting in slow, high-resistance blood flow. This work examined the consequences of these low shear stress conditions on trophoblast migration, adhesion molecule expression, and attraction to chemotactic factors. Methods and results Trophoblasts were cultured on fibronectin or human endothelial cells for 6–12 h under 0.5–6 dyne/cm2 shear stress using the BioFlux200 system, and imaged by time-lapse microscopy. Computer-based imaging algorithms were developed to automatically quantify migration. Chemotaxis assays were run using parallel flow. Trophoblasts cultured on fibronectin or endothelial cells did not undergo directional migration in 0.5 and 2 dyne/cm2 cultures; however, in 4 and 6 dyne/cm2 trophoblasts migrated with the direction of flow ( n = 4, P < 0.001). Shear stresses did not affect the speed of trophoblast migration, or adhesion molecule expression (E-selectin, α4, β1, and αvβ3 integrin). Trophoblasts cultured on endothelial cells migrated into media containing interleukin-8, macrophage chemoattractant protein-1, or Regulated-upon-Activation-Normal-T-cell-Expressed-and-Secreted (RANTES) ( n = 5, P < 0.05). Conclusions Shear stress increases trophoblast migration in the direction of flow, challenging the idea that trophoblasts migrate down spiral arteries retrograde to flow. This suggests that low shear stresses generated by trophoblast plugging of spiral arteries in the first trimester may favour arterial remodelling by preventing the migration with flow seen at higher shear stresses, allowing trophoblasts to migrate down the arteries in response to alternate stimuli such as uterine or endothelial cell-derived chemotactic factors.

Summary Background Southern Africa has a high incidence of bacterial meningitis in adults, often associated with HIV co-infection. Mortality exceeds 50%, even with appropriate antibiotic therapy, and is not improved with corticosteroids. Glycerol adjuvant therapy reduces long-term morbidity in bacterial meningitis in children, and its use is being promoted. We aimed to assess the effectiveness of glycerol as an adjuvant therapy for adults with bacterial meningitis in Africa. Methods The study was done in two phases. First, in an open-label dose-finding study, 45 adult patients with symptoms, signs, and cerebrospinal fluid findings consistent with bacterial meningitis received either 50 mL, 75 mL, or 100 mL of glycerol four times a day for 4 days. We then did a randomised, double-blind, placebo-controlled trial of oral glycerol in adults with bacterial meningitis. Patients with clinical and cerebrospinal fluid findings suggestive of bacterial meningitis were randomly assigned in blocks of 12 by use of a random number list produced by an independent statistician to receive either glycerol or an equivalent volume of sugar solution. Glycerol and placebo were indistinguishable by colour or taste. The primary outcome was mortality at 40 days, with secondary outcomes including disability and mortality restricted to pneumococcal disease. All patients were analysed for the primary outcome excluding those who were lost to follow-up. This trial is registered at controlled-trials.com, number ISRCTN70121840. Findings 75 mL glycerol four times a day was the highest tolerated dose, and was used for the main study. 265 patients were assigned treatment: 137 glycerol and 128 placebo. The trial was stopped early on the advice of the data and safety monitoring board after a planned interim analysis. By day 40, 61 (49%) of 125 patients in the placebo group and 86 (63%) of 136 in the glycerol group had died (adjusted odds ratio 2·4, 95% CI 1·3–4·2, p=0·003). There was no benefit from glycerol for death and disability by day 40, and glycerol did not improve death and disability by day 40 or death at day 40 in patients with proven bacterial disease or pneumococcal disease. Two serious adverse events occurred that were possibly due to the study drug. Interpretation Oral glycerol therapy cannot be recommended as an adjuvant therapy in adults with bacterial meningitis in resource-poor settings with a high HIV prevalence. Funding Meningitis Research Foundation.

The renin-angiotensin (Ang) system is important during placental development. Dysregulation of the renin-Ang system is important in preeclampsia (PE). Female rats transgenic for the human angiotensinogen gene crossed with males transgenic for the human renin gene develop the PE syndrome, whereas those of the opposite cross do not. We used this model to study the role of Ang II in trophoblast invasion, which is shallow in human PE but deeper in this model. We investigated the following groups: PE rats, opposite-cross rats, Ang II–infused rats (1000 ng/kg per day), and control rats. Ang II infusion increased only circulating Ang II levels (267.82 pg/mL), opposite cross influenced only uteroplacental Ang II (13.52 fmol/mg of protein), and PE increased both circulating (251.09 pg/mL) and uteroplacental (19.24 fmol/mg of protein) Ang II. Blood pressure and albuminuria occurred in the models with high circulating Ang II but not in the other models. Trophoblast invasion increased in PE and opposite-cross rats but not in Ang II–infused rats. Correspondingly, uterine artery resistance index increased in Ang II–infused rats but decreased in PE rats. We then studied human trophoblasts and villous explants from first-trimester pregnancies with time-lapse microscopy. Local Ang II dose-dependently increased migration by 75%, invasion by 58%, and motility by 282%. The data suggest that local tissue Ang II stimulates trophoblast invasion in vivo in the rat and in vitro in human cells, a hitherto fore unrecognized function. Conceivably, upregulation of tissue Ang II in the maternal part of the placenta represents an important growth factor for trophoblast invasion and migration.

Rats harboring the human angiotensinogen and human renin genes develop preeclamptic features in pregnancy. The preeclamptic rats exhibit a deeper trophoblast invasion associated with a reduced resistance index by uterine Doppler. Doxycycline inhibits matrix metalloproteinase activity. We tested the hypothesis that matrix metalloproteinase inhibition reduces trophoblast invasion with subsequent changes in placental perfusion. Preeclamptic and pregnant control Sprague-Dawley rats were treated with doxycycline (30 mg/kg of body weight orally) from gestational day 12 until day 18. Placental perfusion was assessed using a micromarker contrast agent. The animals were euthanized on day 18 of pregnancy; biometric data were acquired, and trophoblast invasion was analyzed. Doxycycline resulted in intrauterine growth retardation and lighter placentas in both groups. Maternal body weight was not affected. As shown earlier, preeclamptic rats exhibited a deeper endovascular trophoblast invasion. However, doxycycline treatment reduced trophoblast invasion in the preeclamptic rats. The physiological spiral artery remodeling, as assessed by the deposition of fibrinoid and α-actin in the spiral artery contour, was significantly reduced by doxycycline. The vascularity index, as assessed by perfusion measurement of the placenta, was reduced after doxycycline treatment in preeclamptic rats. Thus, matrix metalloproteinase inhibition with doxycycline leads to reduced trophoblast invasion and associated reduced placental perfusion. These studies are the first to show that reducing trophoblast-induced vascular remodeling decreases subsequent placental perfusion. Our model allows the study of dysregulated trophoblast invasion and vascular remodeling in vivo to gain important insights into preeclampsia-related mechanisms.

In early pregnancy, fetal trophoblasts selectively invade and remodel maternal spiral arteries. A healthy pregnancy is dependent on this adaptation to allow sufficient maternal blood to reach the placenta and the developing fetus. However, little is known of the role played by trophoblasts in this adaptation process. In this study, the interactions between trophoblast cells (TC) and vascular smooth muscle cells (VSMC) were examined using novel live cell image analysis methods which allow quantitative assessment of the behaviour of these two cell types in co-culture. TC and VSMC were simultaneously tracked in co-culture and, for each cell type, directionality, speed and the cell-cell interaction were assessed. The overall migratory behaviour of TC was markedly different in the presence of VSMC with co-cultured TC migrating further with directional movement while mono-cultured TC moved more randomly. Furthermore, TC were shown to specifically target VSMC, suggesting that invading TC may initiate targeted vascular remodelling. Analysis of movement behaviour and cell-cell attraction will be useful in other co-culture systems in addition to answering important questions in the reproductive field.

Remodeling of the uterine spiral arteries during pregnancy transforms them from high to low resistance vessels that lack vasoconstrictive properties. This process is essential to meet the demand for increased blood flow imposed by the growing fetus. Loss of endothelial and smooth muscle cells (SMC) is evident in remodeled arteries but the mechanisms underlying this transformation remain unknown. This study investigated the hypothesis that fetal trophoblast invading from the placenta instigate remodeling by triggering cell death in vascular SMC. Specifically, a role for trophoblast-derived death inducing cytokine tumor necrosis factor-α–related apoptosis-inducing ligand (TRAIL) was investigated. Expression of the activating TRAIL receptors R1 and R2 was detected by flow cytometry on human aortic SMC and by immunohistochemistry on spiral artery SMC. Recombinant human TRAIL induced human aortic SMC apoptosis, which was inhibited by antibodies against TRAIL-R1 or -R2. Perfusion of denuded spiral artery segments with recombinant human TRAIL also induced SMC apoptosis. Trophoblasts isolated from first trimester placenta expressed membrane-associated TRAIL and induced apoptosis of human aortic SMC; apoptosis was significantly inhibited by a recombinant human TRAIL-R1:Fc construct. Trophoblast within the first trimester placental bed also expressed TRAIL. These data show that: 1) TRAIL causes SMC death; 2) trophoblast produce the apoptotic cytokine TRAIL; and 3) trophoblast induce SMC apoptosis via a TRAIL-dependent mechanism. We conclude that TRAIL produced by trophoblast causes apoptosis of SMC and thus may contribute to SMC loss during spiral artery remodeling in pregnancy.

Objectives Activin A, a TGFβ family member, circulates in the maternal blood at increasing concentrations throughout gestation during a healthy pregnancy. The circulating concentration of activin A is further increased in pre-eclampsia (PE), a hypertensive disorder of pregnancy that is marked by systemic maternal vascular endothelial cell dysfunction. The effect of increasing activin A concentrations on the maternal vascular endothelium is unknown. The study aim was to investigate the effect of physiological and pathological activin A concentrations observed in normotensive and PE pregnancies respectively, on vascular endothelial cell function. Methods and results Immunostaining demonstrated the presence of the activin A receptor, ACVR2A, in SGHEC-7 cells used to model the vascular endothelium. SGHEC-7 cells were treated with activin A concentrations representative of concentrations throughout gestation in normotensive (0–10ng/ml) and PE (50ng/ml) pregnancies. xCELLigence functional assays revealed that normotensive activin A concentrations increased SGHEC-7 proliferation and migration, which was inhibited by PE concentrations. Additionally, fluorescence based assays showed that PE concentrations increased endothelial permeability. None of the tested activin A concentrations affected cell apoptosis. PE concentrations also resulted in an imbalance of the vasoactive factors eNOS , PTGIS and EDN1 , as determined by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assays. Conclusion Compared with normotensive activin A concentrations, the higher PE activin A concentrations resulted in abnormal endothelial functions, which may contribute to the systemic maternal vascular endothelial cell dysfunction observed in the disorder.

During pregnancy, trophoblasts migrate from the placenta into uterine spiral arteries, transforming them into wide channels that lack vasoconstrictive properties. In pathological pregnancies, this process is incomplete. To define the fundamental events involved in spiral artery remodeling, we have studied the effect of trophoblasts on vascular smooth muscle cells (SMCs). Here we demonstrate for the first time that apoptosis of SMCs can be initiated by invading trophoblasts. When trophoblasts isolated from normal placenta (primary trophoblasts) or conditioned medium was perfused into spiral or umbilical artery segments, apoptosis of SMCs resulted. Culture of human aortic SMCs (HASMCs) with primary trophoblasts, primary trophoblast-conditioned medium, or a trophoblast-derived cell line (SGHPL-4) also significantly increased SMC apoptosis. Fas is expressed by spiral artery SMCs, and a Fas-activating antibody triggered HASMC apoptosis. Furthermore, a Fas ligand (FasL)-blocking antibody significantly inhibited HASMC apoptosis induced by primary trophoblasts, SGHPL-4, or trophoblast-conditioned medium. Depleting primary trophoblast-conditioned medium of FasL also abrogated SMC apoptosis in vessels in situ. These results suggest that apoptosis triggered by the release of soluble FasL from invading trophoblasts contributes to the loss of smooth muscle from the walls of spiral arteries during pregnancy. Copyright © American Society for Investigative Pathology.

BACKGROUND: Invasion of trophoblast into the uterine environment is crucial for establishing a successful pregnancy. Physiological production of nitric oxide (NO) by extravillous trophoblasts results in significant pro-invasive effects. NO synthesis is competitively inhibited by methylated arginine analogues such as asymmetric dimethylarginine (ADMA) but not the enantiomer symmetric dimethylarginine (SDMA). Within cells, the concentration of ADMA is regulated by the activity of the enzyme dimethylarginine dimethylaminohydrolase (DDAH). The aim of this study was to examine DDAH expression and function in trophoblasts. METHODS AND RESULTS: DDAH-1 and DDAH-2 messenger RNA and protein were demonstrated in first trimester placental tissue, primary extravillous trophoblasts and extravillous trophoblast-derived cell lines. DDAH activity was demonstrated in both cells and tissue. Overexpression of DDAH-1 in trophoblasts led to a number of significant changes, including an 8-fold increase in enzymatic activity, a 59% decrease in production of ADMA (but not SDMA), a 1.9-fold increase in NO and a 1.6-fold increase in cyclic guanosine monophosphate (cGMP) production. Functional assays showed that increased DDAH activity led to significantly increased cell motility and invasion in response to hepatocyte growth factor (HGF). CONCLUSIONS: DDAH may play an important role in the regulation of extravillous trophoblast function via its effects on ADMA and NO production.

Objective We investigated the hypothesis that antiphospholipid antibodies (aPL) have a detrimental effect on human extravillous trophoblast (EVT) differentiation into giant multinucleated cells "in vitro." Design The EVT were isolated from the placental chorion using enzymatic digestion and Percoll gradient centrifugation. After 24, 36, and 48 hours in culture, giant multinuclear cells (GMC) were identified by immunohistochemistry using antibodies to cytokeratin 7 and counted. Setting An academic research laboratory. Patient(s) Placentas were donated by women having an elective cesarean section for a normal pregnancy at term. Main outcome measure(s) This model was then used to investigate the effect of two different monoclonal aPL to β 2 -glycoprotein 1 (IIC5 and ID2), and control mouse IgG antibody on EVT differentiation. Result(s) Freshly isolated EVT were nonproliferative but moved together losing their intervening cell walls and differentiated into GMC. Maximal numbers of GMC were detected after 48 hours of culture. The aPL, IIC5, and ID2 significantly inhibited GMC formation, whereas the mouse IgG control had no effect. Conclusion(s) Antiphospholipid antibodies can inhibit EVT differentiation and GMC formation "in vitro" suggesting that a failure of trophoblast differentiation and subsequent uteroplacental development may be an underlying pathology in antiphospholipid syndrome-associated pregnancy loss.

Decidual natural killer (dNK) cells have been shown to both promote and inhibit trophoblast behavior important for decidual remodeling in pregnancy and have a distinct phenotype compared to peripheral blood NK cells. We investigated whether different levels of oxygen tension, mimicking the physiological conditions of the decidua in early pregnancy, altered cell surface receptor expression and activity of dNK cells and their interactions with trophoblast. dNK cells were isolated from terminated first-trimester pregnancies and cultured in oxygen tensions of 3%, 10%, and 21% for 24 h. Cell surface receptor expression was examined by flow cytometry, and the effects of secreted factors in conditioned medium (CM) on the trophoblast cell line SGHPL-4 were assessed in vitro. SGHPL-4 cells treated with dNK cell CM incubated in oxygen tensions of 10% were significantly more invasive (P < 0.05) and formed endothelial-like networks to a greater extent (P < 0.05) than SGHPL-4 cells treated with dNK cell CM incubated in oxygen tensions of 3% or 21%. After 24 h, a lower percentage of dNK cells expressed CD56 at 21% oxygen (P < 0.05), and an increased percentage of dNK cells expressed NKG2D at 10% oxygen (P < 0.05) compared to other oxygen tensions, with large patient variation. This study demonstrates dNK cell phenotype and secreted factors are modulated by oxygen tension, which induces changes in trophoblast invasion and endovascular-like differentiation. Alterations in dNK cell surface receptor expression and secreted factors at different oxygen tensions may represent regulation of function within the decidua during the first trimester of pregnancy.

Potassium channel α-subunits encoded by KCNQ1-5 genes form voltage-dependent channels (KV7), modulated by KCNE1-5 encoded accessory proteins. The aim was to determine KCNQ and KCNE mRNA expression and assess protein expression/localisation of the KCNQ3 and KCNE5 isoforms in first trimester placental tissue. Placentae were obtained from women undergoing elective surgical termination of pregnancy (TOP) at ≤10 weeks' (early TOP) and >10 weeks' (mid TOP) gestations. KCNQ1-5 expression was unchanged during the first trimester. KCNE5 expression increased in mid TOP vs. early TOP samples (P = 0.022). This novel study reports mRNA and protein expression of KV7 channels in first trimester placentae.

NG,NG-dimethylarginine is an endogenous inhibitor of nitric oxide synthesis produced by endothelial cells and found in the plasma and urine of normal adults. We have examined the ability of NG, NG-dimethylarginine, produced by endothelial cells (SGHEC-7), to regulate the production of nitric oxide by lipopolysaccharide-stimulated mouse macrophage cells (J774.2). Stimulation of SGHEC-7 or J774.2 cells with lipopolysaccharide had no effect on their release of NG,NG-dimethylarginine into the culture supernatant. Stimulation of J774.2 cells with lipopolysaccharide for 24 h significantly stimulated nitric oxide production by J774.2 but not SGHEC-7 cells. When lipopolysaccharide-stimulated J774.2 cells were co-cultured with endothelial cells for 24 h, there was a significant inhibition of nitrite accumulation. The inhibition observed was dependent on the endothelial cell number (12 +/- 5% [mean +/- SEM] following incubation with 0.6 x 105 cells, up to 47 +/- 8% with 4.8 x 105 cells). The inhibitory effect of endothelial cells was prevented by incubation with increasing concentrations of L-arginine; the IC50 was 2.9 +/- 0.6 mM arginine. Western blot analysis indicated that the expression of inducible nitric oxide synthase was not inhibited by co-culture with SGHEC-7 cells. The results presented here demonstrate that NG,NG-dimethylarginine synthesized by endothelial cells may inhibit nitric oxide synthase in adjacent cells and play a role in the regulation of nitric oxide synthesis by macrophages.

A subpopulation of CF-1 mice is unusual in its sensitivity to the avermectins, abamectin and ivermectin, with neurotoxicity occurring at 100-fold lower doses than in other species and mouse strains. We have shown that the sensitive CF-1 mice are deficient in P-glycoprotein in the intestinal epithelium and brain capillary endothelium, tissues forming the principle barriers for penetration into the systemic circulation and central nervous system, respectively. Consistent with the role of P-glycoprotein as a barrier to tissue entry, the plasma and tissue levels of radiolabeled ivermectin in the sensitive mice were markedly higher than in the insensitive mice, particularly in brain, the target organ for toxicity. Insensitive CF-1 and CD-1 mice showed abundant levels of P-glycoprotein in these tissues and tolerated doses of abamectin at least 50-fold the minimum toxic dose in the sensitive subgroup. In view of these findings in CF-1 mice with both abamectin and the structural analog ivermectin, which is used extensively in the treatment of human filariasis with no evidence of neurotoxicity, it is likely that this protein, found in human brain endothelium, is highly conserved in the human population.

Summary The Malawi Adult Meningitis Score prediction tool accurately estimates risk of clinical outcome from bacterial meningitis in sub-Saharan Africa. Clinical trial analysis by risk stratification reveals more severe outcomes in low-risk groups receiving adjunctive glycerol compared to placebo., Background. Acute bacterial meningitis (ABM) in adults residing in resource-poor countries is associated with mortality rates >50%. To improve outcome, interventional trials and standardized clinical algorithms are urgently required. To optimize these processes, we developed and validated an outcome prediction tool to identify ABM patients at greatest risk of death. Methods. We derived a nomogram using mortality predictors derived from a logistic regression model of a discovery database of adult Malawian patients with ABM (n = 523 [65%] cerebrospinal fluid [CSF] culture positive). We validated the nomogram internally using a bootstrap procedure and subsequently used the nomogram scores to further interpret the effects of adjunctive dexamethasone and glycerol using clinical trial data from Malawi. Results. ABM mortality at 6-week follow-up was 54%. Five of 15 variables tested were strongly associated with poor outcome (CSF culture positivity, CSF white blood cell count, hemoglobin, Glasgow Coma Scale, and pulse rate), and were used in the derivation of the Malawi Adult Meningitis Score (MAMS) nomogram. The C-index (area under the curve) was 0.76 (95% confidence interval, .71–.80) and calibration was good (Hosmer-Lemeshow C-statistic = 5.48, df = 8, P = .705). Harmful effects of adjunctive glycerol were observed in groups with relatively low predicted risk of poor outcome (25%–50% risk): Case Fatality Rate of 21% in the placebo group and 52% in the glycerol group (P < .001). This effect was not seen with adjunctive dexamethasone. Conclusions. MAMS provides a novel tool for predicting prognosis and improving interpretation of ABM clinical trials by risk stratification in resource-poor settings. Whether MAMS can be applied to non-HIV-endemic countries requires further evaluation.

Introduction Circulating activin A concentrations are significantly higher in pre-eclampsia (PE) compared with those in a normotensive pregnancy. We and others have previously identified ACVR2A, which codes for the activin A binding receptor, as a maternal PE susceptibility gene with reduced expression in PE. The PE-associated rs1424954 genetic polymorphism also results in decreased receptor expression. Objective Given that PE is characterised by systemic vascular endothelial dysfunction, we used an in vitro cell-line model to investigate how reduced ACVR2A expression modifies the response of maternal vascular endothelial cells to normotensive and PE activin A concentrations. Methods The SGHEC-7 cell line was used as a model of vascular endothelial cells. ACVR2A expression was silenced using siRNA transfection and confirmed with real-time PCR and immunoblotting. A non-targeting siRNA was used as a negative control (NC). Following a 72 h transfection, SGHEC-7s were treated for 24 h with activin A concentrations representative of normotensive (0, 10 ng/ml) and PE (50 ng/ml) pregnancies. SGHEC-7 proliferation was determined using the electrical impedance-based xCELLigence system, while permeability was measured with a Millipore fluorescence-based assay. Student’s t test and one-way ANOVA with Bonferroni’s post-hoc test where appropriate were used for statistical evaluations. Each experiment was performed at least n = 3 times. A p -value of Results ACVR2A siRNA markedly reduced ACVR2A mRNA and protein levels by 78% ( p p p p p p p Conclusions This study demonstrates that decreased expression of the ACVR2A receptor, in addition to activin A, can also result in dysfunctional vascular endothelial proliferation and permeability. Therefore, the altered expression of the ACVR2A receptor, resulting from a genetic predisposition, may modify the threshold required for activin A to impact vascular endothelial function, thereby exacerbating systemic vascular endothelial dysfunction in PE.

Impaired trophoblast invasion is associated with pregnancy disorders such as early pregnancy loss and preeclampsia. There is evidence to suggest that the consumption of caffeine during pregnancy may increase the risk of pregnancy loss; however, little is known about the direct effect of caffeine on normal trophoblast biology. Our objectives were to examine the effect of caffeine on trophoblast migration and motility after stimulation with epidermal growth factor (EGF) and to investigate the intracellular signaling pathways involved in this process. Primary first-trimester extravillous trophoblasts (EVT) and the EVT-derived cell line SGHPL-4 were used to study the effect of caffeine on EGF-stimulated cellular motility using time-lapse microscopy. SGHPL-4 cells were further used to study the effect of caffeine and cAMP on EGF-stimulated invasion of fibrin gels. The influence of caffeine and cAMP on EGF-stimulated intracellular signaling pathways leading to the activation of Akt were investigated by Western blot analysis. Caffeine inhibits both EGF-stimulated primary EVT and SGHPL-4 cell motility. EGF stimulation activates phosphatidylinositol 3-kinase, and Akt and caffeine inhibit this activation. Although cAMP inhibits both motility and invasion, it does not inhibit the activation of Akt, indicating that the effects of caffeine seen in this study are independent of cAMP. Further investigation indicated a role for mammalian target of rapamycin complex 2 (mTORC2) as a target for the inhibitory effect of caffeine. In conclusion, we demonstrate that caffeine inhibits EGF-stimulated trophoblast invasion and motility in vitro and so could adversely influence trophoblast biology in vivo.

Kisspeptin, originally identified as metastatin, important in preventing cancer metastasis, has more recently been shown to be important in pregnancy. Roles indicated for kisspeptin in pregnancy include regulating trophoblast invasion and migration during placentation. The pregnancy-specific disorder pre-eclampsia (PE) is now accepted to begin with inadequate trophoblast invasion and the current study therefore sets out to characterise placental expression of both kisspeptin (KISS1) and its receptor (KISS1R) throughout pregnancy and in PE. Placental tissue was obtained from women undergoing elective surgical termination of early pregnancy (n=10) and from women following Caesarean section at term in normal pregnancy (n=10) and with PE (n=10). Immunohistochemistry of paraffin embedded sections and western immunoblotting were performed to assess protein localisation and expression. Quantitative real-time PCR was carried out to evaluate mRNA expression of both KISS1 and KISS1R. Protein and mRNA expression was found to mirror each other with KISS1 expression found to be reduced in PE compared with that in normal term pregnancy. Interestingly, KISS1R expression at both the mRNA and protein levels was found to be increased in PE compared with that in normal term pregnancy. The current findings of increased KISS1R expression may represent a mechanism by which functional activity of KISS1 is higher in PE than in normal pregnancy. Higher levels of activity of KISS1R may be involved in inhibition of trophoblast invasion and angiogenesis, which are associated with PE.

Background The local actions of glucocorticoids in the placenta can be modulated by 11β-hydroxysteroid dehydrogenase (11βHSD) enzymes, which catalyse inter-conversion of cortisol with its inert metabolite, cortisone, and are known to be expressed in the term placenta and decidua. However, the expression and activity of these enzymes have not been well characterised in the first trimester placenta. The aim of this study was to compare 11βHSD2 expression and activity in first trimester placental tissue from pregnancies at either relatively low or high risk of developing pre-eclampsia as determined by Doppler ultrasound. Methods Enzyme expression was assessed by western blot analysis and immunohistochemistry while 11βHSD enzyme activities were quantified using radiometric conversion of [3H]-cortisol in the presence of NADP + or NAD + . Results 11βHSD2 was expressed in syncytiotrophoblast of first trimester placenta, and there was no difference in the level of expression of placental 11βHSD2 protein between 9 high pre-eclampsia risk and 14 low pre-eclampsia risk pregnancies. NAD + -dependent cortisol oxidation was elevated 3-fold in placental tissue from pregnancies at higher risk of pre-eclampsia than in normal pregnancies (50.9 ± 15.9 versus 18.3 ± 1.9 pmol cortisone/mg protein.10 min, n = 11 & 12, respectively; P Conclusions Expression of 11βHSD2 is thought to protect the fetus from exposure to maternal cortisol. While other studies have suggested that 11βHSD2 is down regulated in term pre-eclamptic placentae, our study suggests that there is increased cortisol inactivation in first trimester placenta prior to week 10 of gestation, from pregnancies at higher risk of developing pre-eclampsia.

The angiotensin II (ANG II) receptor has recently been shown to exhibit subtypes with respect to antagonist binding. Of particular interest are the potent nonpeptide antagonists, DUP 753 and PD 121981, which exhibit selectivity for the subtype 1 (AT1) and subtype 2 (AT2) receptors, respectively. We used these high-affinity antagonists in competition with 125I-[Sar1,Ile8]ANG II to determine autoradiographically the distribution of these ANG II-receptor subtypes in the renal cortex of rats and rhesus monkeys. Binding of the radioligand to receptor in sections of rat renal cortex was inhibited by DUP 753; inhibition by PD 121981 was not detected. By contrast, AT1 and AT2 receptors are present in the renal cortex of rhesus monkeys in regionally distinct structures. DUP 753 inhibited binding to the ANG II receptor in glomeruli. PD 121981 inhibited binding to arterial smooth muscle and the juxtaglomerular (JG) apparatus. The JG apparatus also exhibits radioligand binding, which is inhibited by DUP 753. The effect of DUP 753 and PD 123177 (a more water-soluble analogue of PD 121981) on changes in plasma renin activity was examined to determine if one or both of these subtypes participate in the ANG II-mediated negative feedback of control of renin release. Although DUP 753 increased plasma renin activity to the same extent as the angiotensin-converting enzyme inhibitor, enalaprilat, in rats and rhesus monkeys, the AT2 antagonists did not affect renin release in either species. Thus both subtypes of ANG II receptor are present in rhesus monkey cortex, but a function for only the AT1 subtype was demonstrated.

Progesterone is indispensable for differentiation of human endometrial stromal cells (HESCs) into decidual cells, a process that critically controls embryo implantation. We now show an important role for androgen receptor (AR) signaling in this differentiation process. Decreased posttranslational modification of the AR by small ubiquitin-like modifier (SUMO)-1 in decidualizing cells accounted for increased responsiveness to androgen. By combining small interfering RNA technology with genome-wide expression profiling, we found that AR and progesterone receptor (PR) regulate the expression of distinct decidual gene networks. Ingenuity pathway analysis implicated a preponderance of AR-induced genes in cytoskeletal organization and cell motility, whereas analysis of AR-repressed genes suggested involvement in cell cycle regulation. Functionally, AR depletion prevented differentiation-dependent stress fiber formation and promoted motility and proliferation of decidualizing cells. In comparison, PR depletion perturbed the expression of many more genes, underscoring the importance of this nuclear receptor in diverse cellular functions. However, several PR-dependent genes encode for signaling intermediates, and knockdown of PR, but not AR, compromised activation of WNT/β-catenin, TGFβ/SMAD, and signal transducer and activator of transcription (STAT) pathways in decidualizing cells. Thus, the nonredundant function of the AR in decidualizing HESCs, centered on cytoskeletal organization and cell cycle regulation, implies an important role for androgens in modulating fetal-maternal interactions. Moreover, we show that PR regulates HESC differentiation, at least in part, by reprogramming growth factor and cytokine signal transduction.

BACKGROUND: During pregnancy, extravillous trophoblast invades the uterine wall and enters the spiral arteries. Remodelling ensues, with loss of vascular smooth muscle cells (SMCs) to create high flow, low resistance vessels. Pregnancies complicated by pre-eclampsia are characterized by incomplete arterial remodelling. Endovascular trophoblast is not easily accessible for studies to establish the pathogenesis of pre-eclampsia, so we have developed a model appropriate to carry out mechanistic studies of vessel wall transformation. METHODS AND RESULTS: Segments of human spiral artery were perfused with the choriocarcinoma cell line, BeWo; cells invaded the vessel wall and induced apoptosis of vascular SMC. Perfusion of vessels with BeWo-conditioned medium also induced SMC apoptosis, indicating the presence of a soluble apoptotic factor. BeWo express Fas ligand (FasL) and tumour necrosis factor-related apoptosis-inducing ligand (TRAIL). Treatment of BeWo-conditioned medium with antibodies against FasL inhibited vascular SMC apoptosis in vitro. Antibodies that blocked TRAIL receptor function had no effect. Extracellular matrix degradation is also a prerequisite for vascular remodelling; BeWo express matrix metalloproteinase-12 (MMP-12) and BeWo-conditioned medium increased MMP-12 expression in spiral artery SMC. CONCLUSIONS: BeWo induce arterial remodelling via FasL- and MMP-12-dependent mechanisms. BeWo-derived factors up-regulate protease expression in spiral artery SMC to facilitate matrix breakdown. © The Author 2007. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved.

BACKGROUND: Heparin can significantly reduce pregnancy complications in women with certain thrombophilias, such as antiphospholipid syndrome. Recent reports suggest that heparin may act by mechanisms other than anticoagulation. However, the effect of heparin on trophoblast biology in the absence of thrombophilia has not been extensively investigated. Therefore, this study aimed to evaluate trophoblast invasion, using an established cell line and primary extravillous trophoblasts (EVTs), following exposure to heparin and fractionated heparin. METHODS: An EVT cell line (SGHPL-4) was used to study invasion in the presence of hepatocyte growth factor (HGF) and varying concentrations of fractionated and unfractionated heparin. These experiments were repeated using first trimester primary EVTs. RESULTS: Both forms of heparin significantly reduced HGF-induced invasion in the SGHPL-4 cell line. This suppression of invasion appeared to be dose-dependent for fractionated heparin. In primary EVT cells, fractionated heparin also demonstrated significant suppression of invasion. CONCLUSIONS: Heparin has the potential to reduce trophoblast invasion in cell lines and first trimester EVT cells. This article highlights the need for further evaluation of these medications in vitro and in vivo, especially when used in the absence of thrombophilic disorders.

Tumours derived from DLD-1 colon adenocarcinoma cells, transfected to either overexpress inducible nitric oxide synthase (clone iNOS-19) or with empty vector (pBAN2R), were utilised to test the hypothesis that tumour expression of iNOS (a) increases tumour angiogenesis and (b) modulates the anti-tumour activity of the vascular disrupting agent ZD6126. Overexpression of iNOS by clone iNOS-19 cells and murine xenografts was confirmed by the Griess assay and western blot analysis respectively. Clone iNOS-19 tumours grew more rapidly than pBAN2R tumours. Tumour perfusion, assessed by Hoechst 33342 uptake, was significantly greater in the clone iNOS-19 tumours (P < 0.001). A significant reduction in the perfusion of only the pBAN2R tumours, compared with control, was obtained 24 h after treatment with an intermediate dose of 100 mg/kg ZD6126 (P < 0.001), whereas 200 mg/kg significantly reduced the perfusion of both tumour types (P < 0.001). Whilst pBAN2R tumour necrosis increased in a dose-dependent manner, significant at 100 and 200 mg/kg ZD6126 (P < 0.05), intermediate doses did not induce a similar degree of necrosis in clone iNOS-19 tumours. A significant reduction in splenic perfusion was found 24 h after treatment with 100 mg/kg ZD6126, primarily associated with the red pulp. Overexpression of iNOS increases tumour growth, the degree of functionally perfused vasculature and angiogenesis, and also confers resistance to the vascular disrupting agent ZD6126.

Background— Experimental evidence suggests that estrogens stimulate the production of nitric oxide (NO) by vascular endothelial cells. This effect has been attributed to increased expression and enzymatic activity of both the constitutive and inducible isoforms of NO synthase. In this study, we have investigated whether estrogens regulate the metabolism or release of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO synthase. Methods and Results— The concentration of ADMA in the plasma of 15 postmenopausal women was 0.722±0.04 μmol/L (mean±SEM). Two weeks after subcutaneous implantation with estradiol, there was an increase in plasma estradiol concentration from 0.693±0.075 to 0.81±87 nmol/L, which was accompanied by a significant fall in plasma ADMA concentration to 0.588±0.03 μmol/L ( P =0.006). Human and murine endothelial cell lines previously cultured in estrogen-free medium and then exposed to 17β-estradiol showed a dose-dependent decrease in the release of ADMA. This reached statistical significance at 10 −14 mol/L 17β-estradiol and was accompanied by a corresponding increase in the activity of dimethylarginine dimethylaminohydrolase (DDAH), an enzyme that catalyzes the metabolism of ADMA. Conclusions— We have demonstrated that estrogens can alter the catabolism and release of ADMA in vitro and reduce the circulating concentration in vivo. We therefore propose that increased DDAH activity and the subsequent fall in ADMA could contribute to the positive effect of estrogen on NO synthesis.

Apoptosis is thought to play an important regulatory role in placental development and inappropriate trophoblast apoptosis has been implicated in complications of pregnancy such as pre-eclampsia. Here we show that apoptosis of a human extravillous trophoblast-derived cell line (SGHPL-4) can be regulated by nitric oxide (NO). Nitric oxide produced exogenously by the addition of NO donors was able to delay or inhibit apoptosis induced by a combination of tumour necrosis factor alpha and actinomycin D and to suppress the activity of caspase 3. Treatment with hepatocyte growth factor (HGF) stimulated expression of the inducible isoform of NO synthase and was also able to protect SGHPL-4 cells from caspase 3 activation and apoptosis. The inhibition of basal NO production with NO synthase inhibitors was shown to sensitise cells to apoptotic stimuli and to reduce the level of endogenous caspase 3 nitrosylation. The anti-apoptotic effects of NO in these extravillous trophoblast cells appear to be mediated through the production of cyclic GMP as inhibitors of soluble guanylate cyclase inhibited the protective effect of both HGF and NO donors.

There is accumulating evidence that deficient trophoblast invasion of the placental bed spiral arteries is crucial to the pathogenesis of pre-eclampsia and intrauterine growth restriction. However, the factors which regulate the process of trophoblast invasion remain unclear. We have investigated whether extravillous trophoblast invasion and motility are mediated by the angiogenic growth factors, vascular endothelial growth factor (VEGF) and placental growth factor (PlGF). The SGHPL-4 extravillous trophoblast cell line was utilized. Expression of mRNA for the receptors of VEGF and PlGF (KDR and flt-1) was determined using the reverse transcriptase polymerase chain reaction. An in vitro model of invasion assessed the number and length of trophoblast processes invading into an extracellular matrix. The motility of cells under standard culture conditions was also quantified. The effect of the addition of VEGF and PlGF (±heparin) on trophoblast invasion and motility was determined. The effect of VEGF and PlGF (±heparin) on SGHPL-4 cell proliferation was assessed by cell counts at 24, 48 and 72h post-addition of growth factor. The SGHPL-4 cells expressed mRNA for the flt-1 but not the KDR receptor. The addition of VEGF resulted in a significant decrease in the number of trophoblast processes formed ( P 0.02); this effect was not influenced by the addition of heparin. However, there was no effect on the length of processes formed in response to VEGF (±heparin). The addition of PlGF had no effect on either the number or the length of processes formed. The addition of VEGF increased the motility of the SGHPL-4 cells ( P 0.002); the addition of heparin prevented this VEGF-induced increase in motility. The addition of PlGF had no effect on SGHPL-4 motility (±heparin). Neither growth factor had any effect on the proliferative ability of SGHPL-4 cells. Contrary to our hypothesis, we did not find that the angiogenic growth factors, VEGF and PlGF, mediated the in vitro invasion of trophoblast cells into an extracellular matrix. However, VEGF did increase trophoblast motility. Our findings of an effect of VEGF on trophoblast motility (and possibly invasion) suggests the presence of functional receptors, which can mediate the actions of VEGF. Caution must be exercised before any extrapolation to the in vivo situation, however, it could be speculated that the increased motility in response to VEGF may be an initial response to attract trophoblast cells to the decidua, and that VEGF might then limit the degree to which trophoblast cells invade.

Naproxen sodium was administered to cynomolgus monkeys (Macaca fascicularis) by oral gavage at daily doses of 44, 88, or 176 mg/kg for 2 wk (2 monkeys/gender) or of 44 mg/kg for 13 wk (4 monkeys/gender). Body weight loss occurred in at least one monkey in all naproxen sodium-dosed groups in the 2-wk (up to 16% loss) and 13-wk (up to 22% loss) studies. Increases in plasma naproxen concentrations were dose proportional between 44 and 88 mg/kg but were less than dose proportional between 88 and 176 mg/kg. Up to 2-fold increases in creatinine and/or serum urea nitrogen values as well as higher renal weights occurred in monkeys receiving 176 mg/kg for 2 wk or 44 mg/kg for 13 wk. Microscopically, renal changes were observed in all naproxen sodium-dosed groups. Renal findings after 2 wk of exposure included increased interstitial ground substance, tubular dilatation, and tubulointerstitial nephritis; in the 13-wk study, cortical tubular atrophy and interstitial fibrosis were also observed. These studies identify the kidney as the target organ of naproxen sodium in cynomolgus monkeys.

Captopril, an angiotensin II-converting enzyme inhibitor, ameliorates the renal mesangial lesions associated with subtotal nephrectomy, a process associated with increased mesangial macromolecular flux and injury. In the present study uninephrectomized rats with proteinuria and focal glomerular sclerosis had increased mesangial heat-aggregated human IgG (AHIgG) uptake. However, uninephrectomized rats treated daily with captopril, which failed to develop either glomerular lesions or proteinuria, also had significantly elevated mesangial AHIgG levels. Our results suggest that increased mesangial macromolecular flux may occur independent of altered glomerular permselectivity changes and proteinuria and appears to be related to glomerular hyperfiltration rather than glomerular hypertension. Further, glomerular mesangial sclerosis may not be the direct result of increased mesangial macromolecular flux.

The biphasic shape of the survival curve of 99 patients with aplastic anemia suggested that there may be at least two subgroups of patients with this disease, one with a very short survival and another with a longer survival. Patients who survived for 4 mo or less after the first clinic visit (group A) were different from the patients who survived longer (group B) with respect to their modes of onset, sex, intervals from the onset of symptoms to first clinic visit, and initial hematologic values. These differences suggested that short survival could be predicted from data available at the first contact with the physician. From these measurements, a prognostic index could be calculated which was useful in identifying the patients in group A. Although this method of prognostication needs further testing, if validated, it may prove useful in selecting patients for therapeutic trials and could explain the divergent results in previous studies of androgen treatment of aplastic anemia. When our androgen-treated subjects were compared with subjects with a similar prognostic index who had not received androgens, a beneficial effect of androgen therapy on survival could not be demonstrated.

The ultrastructural and erythrokinetic characteristics of vitamin E deficiency in swine were investigated in an effort to evaluate the suitability of the swine disorder as a model of the human congenital dyserythropoietic anemias. The dominant erythrokinetic abnormality in vitamin E deficient pigs, as in the CDAs, is ineffective erythropoiesis. As in some patients with CDA, the activity of a number of erythrocyte enzymes was increased. Distinctive ultrastructual changes previously described in patients with CDA were found in normoblasts from vitamin E deficient pigs. The morphologic, erythrokinetic, biochemical and ultrastructural similarities between vitamin E deficiency in swine and the CDAs in man appear to justify the study of the animal disorder as a model of the human disease. A complete hematologic response was elicited by the administration not only of vitamin E, but also, as in the previous studies of vitamin E deficiency in monkeys, by hexahydrocoenzyme Q4. The partial hematologic response occurring after deletion of tocopherol stripped corn oil from the diet indicates that factors other than the dietary lack of vitamin E are important in the pathogenesis of this disorder.

The azide-resistant ferroxidase activity of fresh, undialyzed human serum, either normal or from patients with Wilson's disease, can be accounted for by citrate and by the incomplete inhibition of ceruloplasmin ferroxidase activity in 1 mM concentrations of NaN3. Prolonged dialysis of serum at pH 5.5 resulted in the development of appreciable ferroxidase activity when the dialyzed serum was assayed at pH 6.0 in acetate buffer. This activity could not be accounted for by either citrate or ceruloplasmin and corresponds to the ferroxidase II activity reported by others. Since this activity was not detected in human serum under physiologic conditions and its activity was a function of the pH, duration and temperature of dialysis, its physiologic role in iron metabolism has not been established.

Three-hundred and ninety-nine patients with acute leukemia examined during the period 1947-1964 were divided into three sequential series and their survival, from diagnosis to death, was compared. A statistically significant increase in duration of survival for myeloblastic leukemia from a median of 2 to 5 months occurred between series I and series III. This is the first convincing evidence that 6-mercaptopurine therapy influences survival in myeloblastic leukemia. A steady increase in median survival of patients with lymphoblastic leukemia from 4 to 8 to 12 months was found in the three series. The results of analysis of these series are compared to other reported series. The hypothesis —that the longer survivals reported for patients treated in hematology clinics compared to that of patients selected from population areas reflects patient selection—was examined and appeared unlikely.

SummaryStudies were undertaken to characterize more definitively the effect of endotoxin upon neutrophil kinetics. The data presented herein indicate that the neutrophil response to endotoxin in the mouse is dose related. With relatively small doses of endotoxin, neutrophilia appeared earlier, was of greater magnitude and was not preceded by neutropenia. After larger doses, neutropenia persisted for several hours and was later followed by neutrophilia.The response in marrow neutrophils was determined at 6 and 16 hours following the injection of endotoxin in order to correlate changes occurring in the marrow with those observed in the blood. Smaller doses of endotoxin resulted in an earlier and greater degree of blood neutrophilia than did larger doses but fewer cells were released from the marrow after small doses than after large doses.At least 2 dose related kinetic events explain the neutrophil changes occurring after the administration of endotoxin. With small doses of endotoxin, the acceleration of r...

1. A total of 70 swine were fed a diet consisting only of evaporated cow’s milk. Copper and iron were added to the diet of 10 of the pigs. Iron only was added to the diet of 46 of the pigs. Copper only was added to the diet of 10 of the pigs. Four pigs received neither iron or copper. 2. The animals deficient in copper developed skeletal abnormalities, microcytic hypochromic anemia, leukopenia, neutropenia, normoblastic hyperplasia of the bone marrow, hypoferremia, an increase in the iron-binding capacity of the plasma, hypocupremia and reduced erythrocyte copper as well as tissue copper. No abnormality in porphyrin metabolism was observed and tissue as well as erythrocyte catalase activity was not significantly reduced. Following the administration of copper, the blood of the animals was rapidly and completely restored to normal. 3. The animals deficient in iron developed a severe microcytic, hypochromic anemia, normoblastic hyperplasia of the bone marrow, hypoferremia and an increase in the total iron-binding capacity of the plasma. No abnormality in copper or porphyrin metabolism was observed in these animals except for a slight elevation in the plasma copper level and a marked increase in liver copper. 4. The animals deficient in both copper and iron developed all of the manifestations noted in the copper-deficient pigs. These changes occurred more rapidly and to a greater degree than in the swine with a deficiency of either element alone. 5. The morphologic and biochemical similarities between anemia due to copper deficiency and anemia due to iron deficiency suggest that in copper-deficient swine there is an abnormality in the metabolism of iron and that, furthermore, the anemia may be the consequence of this abnormality.

1. The amount of free coproporphyrin and protoporphyrin its the erythrocytes of twenty normal male subjects was found to be 0.76 ± 0.26 and 31.3 ± 11.9 µg./100 ml. of packed RBC, respectively. In ten normal female subjects the values were 0.71 ± 0.23 and 44.6 ± 19.6 µg./100 ml. of packed RBC, respectively. 2. In eighteen male patients with chronic infection, mean values of 1.53 ± 0.61 µg./100 ml. of packed RBC for free erythrocyte coproporphyrin and 181.2 ± 90.6 µg./100 ml. of packed RBC for free erythrocyte protoporphyrin were found.