Characterization of the neutrophil molecules identified by quinine- dependent antibodies from two patients

BACKGROUND: Two patients with episodic pancytopenia and renal failure associated with quinine (Qn) ingestion were previously found to have Qn- dependent antibodies that reacted with red cells, platelets, and neutrophils. The purpose of these studies was to characterize the neutrophil antigens recognized by Qn-dependent antibodies from these two patients. STUDY DESIGN AND METHODS: The neutrophil molecules recognized by the Qn-dependent antibodies in the sera from the two patients were analyzed by immunoprecipitation using 125I-labeled neutrophils. Neutrophils from 13 different donors were tested. RESULTS: The Qn-dependent antibodies from Patient 1 immunoprecipitated a 60-kDa molecule on neutrophils from seven donors and an 85-kDa molecule on neutrophils from three donors. The Qn-dependent antibodies from Patient 2 reacted with a 32-kDa molecule on neutrophils from 5 donors, a 60-kDa molecule on neutrophils from 9 donors, and an 85-kDa molecule on neutrophils from 10 donors. Neutrophil-specific antigen NB1 is also located on a 60-kDa glycoprotein (GP). While the antibody in serum from Patient 1 did not show specificity for NB1, the antibody from Patient 2 detected the 60-kDa molecule on NB1-positive neutrophils from 9 of 11 donors tested and did not detect the 60-kDa molecule on NB1-negative neutrophils from 2 donors. In a monoclonal antibody immobilization of granulocyte antigens assay, the Qn-dependent antibody from both patients reacted with the 60-kDa molecule carrying NB1. The Qn- dependent antibody from a third patient, Patient 3, was previously found to react with an 85-kDa GP and the 60-kDa NB1 GP. To determine if the Qn-dependent antibodies from Patients 2 and 3 recognized the same 85-kDa GP, neutrophils were treated with serum from Patient 3 plus Qn to remove the 85-kDa GP. Then, serum from Patient 2 plus Qn no longer immunoprecipitated the 85-kDa GP. CONCLUSION: The antigens recognized by Qn-dependent neutrophil antibodies were located on molecules of 85, 60, and 32 kDa. Qn-dependent antibodies from two patients reacted with the same 85-kDa GP and those from three patients reacted with the same 60-kDa GP. The 60-kDa molecule recognized by the Qn-dependent antibodies carried the NB1 antigen.     

Mathematical analysis of isovolemic hemodilution indicates that it can decrease the need for allogeneic blood transfusion

BACKGROUND: The implementation of acute isovolemic hemodilution prior to surgical blood loss is a strategy used in an attempt to diminish the need for or obviate allogeneic transfusion and to avert the potential, attendant complications. Studies examining the efficacy of this technique have produced conflicting results. STUDY DESIGN AND METHODS: The present mathematical analysis was undertaken to resolve these conflicts by determining the efficacy of hemodilution and examining the influence of the variables affecting the outcome. Efficacy was defined as the volume of additional blood loss permitted and the volume and number of units of allogeneic blood saved from transfusion. A mathematical analysis evaluated the impact of circulating blood volume and initial and target hematocrits on the efficacy of isovolemic hemodilution. It was assumed that 1) hemodilution was completed before surgical blood loss; 2) transfusion of removed blood was begun when the target hematocrit was reached and lost surgical blood was replaced at a rate that maintained the target hematocrit; 3) allogeneic transfusion was begun after all autologous blood drawn was transfused; 4) normovolemia was maintained; and 5) a unit of allogeneic blood contains 175 mL of red cells. RESULTS: The analysis showed that isovolemic hemodilution can result in substantial additional allowable surgical blood loss that can diminish the need for or obviate allogeneic transfusion of red cells. Larger circulating blood volume, higher initial hematocrits, and lower target hematocrits increase the efficacy of hemodilution. Removal and isovolemic replacement of 1 to 2 units of blood provide minimal potential savings, as does hemodilution to a circulating (target) hematocrit of 30 percent. The extension of hemodilution to a hematocrit of (or below) 20 percent allows a disproportionately greater surgical blood loss and diminishes the need for allogeneic transfusion. It allows, for example, an additional 4.5 L of surgical blood loss, which represents a savings of 4 units of allogeneic blood when a patient with an initial blood volume of 5.0 L and a hematocrit of 45 percent undergoes isovolemic hemodilution to a hematocrit of 15 percent. CONCLUSION: Isovolemic hemodilution can diminish or in some circumstances eliminate the need for allogeneic transfusion.     

Design and synergistic effect of nano-sized epoxy-NiCo2O4 nanocomposites for anticorrosion applications

In the present work, we evaluated the corrosion inhibition properties of a ligand and mixed metal oxide nanocomposite. The ligand and mixed nickel–cobalt complex were synthesized using 1-naphthoic acid and aminoguanidine with the formulae [C₁₁H₇O₂(CN₄H₅)(CN₄H₆)]·H₂O and {Ni–Co[(CH₅N₄)₂(C₁₁H₇O₂)₂]}·H₂O, respectively. After their synthesis, physicochemical techniques such as CHNS analysis, infrared and UV-visible spectroscopy, thermal analysis, and X-ray diffraction (XRD) were employed to characterize both the synthesized ligand and nickel–cobalt complex. The metal oxide prepared from the decomposition of the metal complex was also characterized using several techniques to confirm its bonding and structure. In addition, the corrosion inhibition efficiency of the epoxy-ligand and epoxy-NiCo₂O₄ nanocomposite on mild steel (MS) in 3 M hydrochloric acid (HCl), 1.5 M sulfuric acid (H₂SO₄), and 0.5 M phosphoric acid (H₃PO₄) solution was examined and compared using weight loss measurements, Tafel plots, isotherms and electrochemical impedance spectroscopy (EIS). The results from the electrochemical studies disclosed that the epoxy coating of mixed metal oxides with 0.8 ppm concentration yielded excellent corrosion protection. The SEM images of mild steel and mild steel coated with epoxy-ligand/epoxy-NiCo₂O₄ in HCl confirmed the anti-corrosive behavior of the synthesized compounds. Hence, the as-prepared material can be a next-generation tool for sustainable anti-corrosive coatings.

This study reports the synthesis of nano-sized epoxy-NiCo₂O₄ nanocomposites and their anti-corrosive efficiency to attain sustainable development.     

Protein tyrosine phosphatase receptor type delta (PTPRD) gene in an animal model of restless legs syndrome

The pathophysiology of the restless legs syndrome (RLS) is related to dopaminergic dysfunction, reduced iron and variations in gene expression, such as the protein tyrosine phosphatase receptor type delta gene (PTPRD). Animal models could be key to achieving a mechanistic understanding of RLS and to facilitate efficient platforms for evaluating new therapeutics. Thus, the aim of this study was to evaluate the expression of PTPRD, of genes and proteins associated with RLS, the sleep patterns and the cardiovascular parameters in an animal model of RLS (spontaneously hypertensive rat [SHR]). Rats were divided into two groups: (i) Wistar-Kyoto and (ii) SHR. Cardiovascular parameters were assessed by tail plethysmography. Polysomnography was used to analyse the sleep pattern (24 h). For the PTPRD analyses, quantitative polymerase chain reaction (qPCR) and indirect enzyme-linked immunosorbent assay (ELISA) techniques were used. To evaluate the tyrosine hydroxylase enzyme, dopamine transporter (DAT) and type 2 dopaminergic receptor, qPCR and Western Blotting techniques were used. For the quantification of iron, ferritin and transferrin, the ELISA method was used. SHRs had higher blood pressure, alterations in sleep pattern, lower expression of protein content of PTPRD, lower expression of DAT, and lower serum concentrations of ferritin. These data suggest that the behavioural, physiological, and molecular changes observed in SHRs provide a useful animal model of RLS, reinforcing the importance of this strain as an animal model of this sleep disorder.     

Cannabidiol reduces lipopolysaccharide-induced nociception via endocannabinoid system activation

Bacterial infections are often accompanied by fever and generalized muscle pain. However, the treatment of pain with an infectious aetiology has been overlooked. Thus, we investigated the impact of cannabidiol (CBD) in bacterial lipopolysaccharide (LPS)-induced nociception. Male Swiss mice received intrathecal (i.t.) LPS injection, and the nociceptive threshold was measured by the von Frey filaments test. Spinal involvement of the cannabinoid CB₂ receptor, toll-like receptor 4 (TLR4), microglia and astrocytes were evaluated by i.t. administration of their respectively antagonists or inhibitors. Western blot, immunofluorescence, ELISA and liquid chromatography-mass spectrometry were used to assess Cannabinoid CB₂ receptors and TLR4 spinal expression, proinflammatory cytokines and endocannabinoid levels. CBD was administered intraperitoneally at 10 mg/kg. The pharmacological assay demonstrated TLR4 participation in LPS-induced nociception. In addition, spinal TLR4 expression and proinflammatory cytokine levels were increased in this process. CBD treatment prevented LPS-induced nociception and TLR4 expression. AM630 reversed antinociception and reduced CBD-induced endocannabinoids up-regulation. Increased spinal expression of the cannabinoid CB₂ receptor was also found in animals receiving LPS, which was accompanied by reduced TLR4 expression in CBD-treated mice. Taken together, our findings indicated that CBD is a potential treatment strategy to control LPS-induced pain by attenuating TLR4 activation via the endocannabinoid system.