Phagocytosis of heat‐killed Staphylococcus aureus by eosinophils: comparison with neutrophils

Eosinophils are characterized by several functional properties, such as chemotaxis, adhesion, superoxide anion production, and degranulation. In this article, we have studied the role of bacterial ingestion by eosinophils in comparison with that by neutrophils. Eosinophils and neutrophils were purified by using the Percoll gradient method followed by selection with CD16‐coated immunomagnetic beads and centrifugation through a Ficoll‐Hypaque gradient combined with dextran sedimentation, respectively. Both cells were preincubated with anti‐FcγRIIa mAb (CD32 mAb), anti‐FcγRIIIb mAb (CD16 mAb), anti‐CR3 (CD11b mAb), or anti‐CR1 (CD35 mAb) before being examined for phagocytosis of opsonized heat‐killed Staphylococcus aureus (S. aureus). Phagocytosis and production of hydrogen peroxide were simultaneously measured by flow cytometry using S. aureus labeled with propidium iodide and stained with 2′,7′‐dichlorofluorescein diacetate. Eosinophils showed significantly lower activity than neutrophils in both phagocytosis and hydrogen peroxide production. Phagocytosis by both cells was decreased by heat‐inactivated serum. Phagocytosis by neutrophils was significantly inhibited by CD16 mAb and CD32 mAb, whereas that by eosinophils was only inhibited by CD35 mAb. Whereas the mechanism of phagocytosis by neutrophils was mediated by CD16 and CD32, that of eosinophils was modulated by complement receptor 1 (CD35).     

A case of West syndrome with atypical massive gray matter heterotopia that is well controlled by ACTH therapy

A 4 month old female infant with atypical asymmetrical massive gray matter heterotopia diagnosed as West syndrome is described. Her seizure initially appeared as afebrile general tonic and clonic convulsion and progressed to typical West syndrome consisting of clusters of myoclonic spasms of the extremities, mainly on the left side, accompanied by head and eye deviation to the right side. Electroencephalogram (EEG) presented typical hypsarrhythmia and cranial computerized tomography (CT) and magnetic resonance imaging (MRI) showed massive heterotopic gray matter in the right hemisphere with the same density or intensity as cortical gray matter. Single photon emission computed tomography (SPECT), using N-isopropyl-p-¹²³I-iodoamphetamine (¹²³I-IMP), demonstrated decreased blood flow in the ectopic lesion. Although clinical response to several anti-epileptic drugs was poor, her seizures were well controlled by relatively low dose adrenocorticotropic hormone (ACTH) therapy of 0.015 mg/kg per day followed by a combination of valproic acid and clonazepam.     

Bile acids influence hepatic chemiluminescence in normal and oxidative-stressed rats†

The aim of the present study was to clarify whether bile acids influence chemiluminescence (CL) in the liver in vivo. Hepatic CL was determined on the surface of the liver of anaesthetized rats by using a photon counter. In normal rats, hepatic CL was significantly decreased 30 min after enteral administration of chenodeoxycholic acid (CDCA) or deoxycholic acid (DCA), but returned to its initial level 3 h later, after part of the CDCA administered was metabolized. Ursodeoxycholic acid (UDCA) and cholic acid had no effect on CL. In contrast, hepatic CL was markedly increased 30 min after CDCA or DCA administration in rats given either buthionine sulphoximine (BSO), an inhibitor of γ-glutamylcysteine synthetase, or diethyldithiocarbamate (DDC), an inhibitor of both superoxide dismutase and glutathione peroxidase. Chenodeoxycholic acid further increased the CL of BSO- or DDC-treated rats during inhalation of oxygen via a tracheal cannula. Coadministration of UDCA eliminated the effects of CDCA on the hepatic CL of normal and BSO- or DDC-treated rats with or without oxygen inhalation. We conclude that cytotoxic bile acids, such as CDCA, increase CL in the antioxidants-depleted or oxidative-stressed liver in vivc, but that UDCA prevents CDCA from developing CL.     

Clinical pharmacological study of a plasma‐derived factor VIIa and factor X mixture (MC710) in haemophilia patients with inhibitors – Phase I trial

Summary. MC710, a combined product of plasma‐derived activated factor VII (FVIIa) and factor X (FX) at a protein weight ratio of 1:10, is a novel bypassing agent for haemostasis in haemophilia patients with inhibitors. In this study, pharmacokinetic (PK), pharmacodynamic (PD) parameters and safety of single doses of MC710 were investigated in 11 male haemophilia patients with inhibitors in a non‐bleeding state. This was a multi‐centre, open‐labelled, non‐randomized, active controlled crossover, dose‐escalation study of five doses (20–120 μg kg⁻¹ of FVIIa) with re‐administration of different MC710 dosages to the same subjects. The active controls were NovoSeven (120 μg kg⁻¹) and/or FEIBA (50 and 75 U kg⁻¹) which were used to compare PD parameters. The area under the curve (AUC) and maximum plasma concentration (C_max) of MC710 active ingredients increased dose‐dependently within the range of 20 and 120 μg kg⁻¹. After administration of MC710, activated partial thromboplastin time (APTT) was dose‐dependently improved and prothrombin time (PT) was shortened to approximately 6 s at 10 min, and APTT improvement and PT shortening effects were maintained until 12 h after administration of MC710 at all doses. No serious or severe adverse event was observed after administration of MC710; furthermore, several diagnostic marker values and those changes did not indicate any signs of disseminated intravascular coagulation (DIC). These results suggest that MC710 would have haemostatic potential equal to or greater than NovoSeven and FEIBA and was be tolerable when given at doses up to 120 μg kg⁻¹.     

Haemophilia A: effects of inhibitory antibodies on factor VIII functional interactions and approaches to prevent their action

Factor VIII (FVIII) is an essential component of the intrinsic pathway of blood coagulation. Normal functioning of FVIII requires its interactions with other components of the coagulation cascade. In the circulation, it exists as a complex with von Willebrand factor (vWF). Upon activation by thrombin or activated factor X (FXa), activated FVIII (FVIIIa) functions as a cofactor for the serine protease factor IXa. Their complex assembled on the phospholipid surface activates FX to FXa, which consequently participates in formation of thrombin, the key protease of the coagulation cascade. Genetic deficiency in FVIII results in a coagulation disorder haemophilia A, which is treated by infusions of FVIII products. Approximately 25-30% of patients develop antibodies inhibiting FVIII activity (FVIII inhibitors). The major epitopes of inhibitors are located within the A2, C2 and A3 domains of the FVIII molecule. The inhibitory effects of antibodies are manifested at various stages of the FVIII functional pathway, including FVIII binding to vWF, activation of FVIII by thrombin, and FVIIIa incorporation into the Xase complex. We summarize the current knowledge of the FVIII sites involved in interaction with its physiological ligands and different classes of inhibitory antibodies and describe their inhibitory mechanisms. We outline the strategies aimed to overcome the effects of inhibitory antibodies such as development of human/porcine FVIII molecules, resistant to inhibitors. We also discuss approaches to modulate the antibody response, as well as efforts to develop a long-term immunotolerance to FVIII protein.     

Social support and pregnancy:II. Its relationship with depressive symptoms among Japanese women

Abstract In a questionnaire survey among 1329 first-trimester pregnant women, both the husband support measures and unwanted pregnancy ('stressor' agent in pregnancy) showed significant effects on an elevated score of the cognitive disturbance subscale of the Zung's self-rating depression scale (SDS), while only unwanted pregnancies showed an effect on an elevated score of the dysphoric mood subscale of the SDS. However, no interaction was observed between the husband support measures and unwanted pregnancy, therefore the effect of the husband's social support on the cognitive disturbance score was not that of a buffer, but rather a main effector. Finally, multiple regression analyses showed that the dysphoric mood score was preceded by unwanted pregnancy, premenstrual irritability, public self-consciousness, and maternal overprotection; while the cognitive disturbance score was preceded by unwanted pregnancy, husband reduced 'given' and 'giving' support, maternal reduced care and overprotection, paternal reduced care, low annual income, low private self-consciousness, and smoking. These findings suggest that the husband's support for a pregnant woman is effective only in reducing cognitive symptoms, and that different symptomatic constellations have different sets of psychosocial correlates.     

A consensus statement on clinical trials of bypassing agent prophylaxis in inhibitor patients

Summary. The haemophilia literature increasingly contains reports describing the use of bypassing agent prophylaxis (BAP) in patients with severe haemophilia A and inhibitors. However, it is difficult to interpret and compare the results and draw conclusions about treatment efficacy because of small patient numbers and a lack of standardization among BAP studies. This article presents consensus recommendations for standardizing future BAP clinical trials developed by an international panel of haemophilia opinion leaders.