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Thalassaemia is one of the commonest inherited genetic disorders world-wide with around 25,000 births of the most severely affected transfusion dependent children annually. Patients with transfusion dependent thalassaemia require regular blood transfusions to maintain life but because of this will develop iron overload. To remove the excess iron, patients are required to take iron chelation therapy (ICT). ICT requires lifelong adherence to treatment to prevent end organ damage from developing. Many of these preventable complications make adherence to therapy more complex for patients. In this review, we focus on two commonly encountered patient scenarios and discuss how different psychological models and a relational theory can be used to understand and support adherence to treatment., Competing Interests: Dr Farrukh T Shah reports personal fees from Celgene International, Bluebird bio Inc, Novartis Pharma AG, Vertex Pharmaceuticals, Chiesi Ltd, Bristol Myers Squibb Pharmaceuticals Ltd, Silence Therapeutics plc, and Agios Pharmaceuticals Ltd, outside the submitted work. The authors report no other conflicts of interest in this work., (© 2022 Eziefula et al.)

Early reports have demonstrated the occurrence of glyoxylate cycle enzymes in several Leishmania species. However, these results have been underestimated because genes for the two key enzymes of the cycle, isocitrate lyase (ICL) and malate synthase (MS), are not annotated in Leishmania genomes. We have re-examined this issue in promastigotes of Leishmania amazonensis. Enzyme activities were assayed spectrophotometrically in cellular extracts and characterized partially. A 40 kDa band displaying ICL activity was visualized on zymograms of the extracts. By immunoblotting with mouse antibodies against ICL from Bacillus stearothermophilus, a band of approximately 40 kDa was identified, coincident with the relative molecular mass of the activity band revealed on zymograms. Indirect immunofluorescence of intact promastigotes showed that the recognized antigen is distributed as a punctuated pattern, mainly distributed beneath the subpellicular microtubules, over a diffused cytoplasmic stain. These results clearly demonstrate the existence of an apparent ICL activity in L. amazonensis promastigotes, which is associated to a 40 kDa polypeptide and distributed both diffused and as punctuate aggregates in the cytoplasm. The relevance of this activity is discussed.

In the present work we have studied in vitro the effect of increasing red cell Ca 2+ ions on human erythrophagocytosis by peripheral monocyte-derived autologous macrophages. In addition, the relative contribution to phagocytosis of phosphatidylserine exposure, autologous IgG binding, complement deposition and Gárdos channel activity was also investigated. Monocytes were obtained after ficoll-hypaque fractionation and induced to transform by adherence to glass coverslips, for 24 h at 37°C in a RPMI medium, containing 10% fetal calf serum. Red blood cells (RBC) were loaded with Ca 2+ using 10 μM A23187 and 1 mM Ca-EGTA buffers, in the absence of Mg 2+ . Ca 2+ -loaded cells were transferred to above coverslips and incubated for 2 h at 37°C under various experimental conditions, after which phagocytosis was assessed by light microscopy. Confirming earlier findings, phagocytosis depended on internal Ca 2+ . Accordingly; it was linearly raised from about 2-15% by increasing the free Ca 2+ content of the loading solution from 0.5 to 20 μM, respectively. Such a linear increase was virtually doubled by the presence of 40% autologous serum. At 7 μM Ca 2+ , the phagocytosis degree attained with serum was practically equal to that obtained with either 2 mg/ml affinity-purified IgG or 40% IgG-depleted serum. However, phagocytosis was reduced to levels found with Ca 2+ alone when IgG-depleted serum was inactivated by heat, implying an involvement of complement. On the other hand, phagocytosis in the absence of serum was markedly reduced by preincubating macrophages with phosphatidylserine-containing liposomes. In contrast, a similar incubation in the presence of serum affected it partially whereas employing liposomes made only of phosphatidylcholine essentially had no effect. Significantly, the Gárdos channel inhibitors clotrimazole (2 μM) and TRAM-34 (100 nM) fully blocked serum-dependent phagocytosis. These findings show that a raised internal Ca 2+ promotes erythrophagocytosis by independently triggering phosphatidylserine externalization, complement deposition and IgG binding. Serum appeared to stimulate phagocytosis in a way dependent on Gárdos activity. It seems likely that Ca 2+ promoted IgG-binding to erythrocytes via Gárdos channel activation. This can be an important signal for clearance of senescent human erythrocytes under physiological conditions.

New synthetic compounds based on tetrahydroindenoquinoline structure were evaluated for their in vitro antileishmanial activities. The seven compounds assayed have antiproliferative activities against promastigotes of Leishmania mexicana. Compound 1 and 3 were the most active (IC50 1.0 μg/ml) and showed high selectivity towards the parasite. These compounds were selected to evaluate their effect on promastigote morphology and mitochondrial transmembrane potential as well as on the amastigote capability to survive into macrophages J774 cell line. Whereas compound 1 affected the promastigote cell cycle, compound 3 induced morphological changes and the total collapse of the mitochondrial transmembrane potential, a hallmark of apoptosis. Both compounds also affected the amastigote form of the parasite, decreasing their survival rate in J774 macrophages. Due to the greatest selectivity index, the apparent effect as apoptotic inducer and its sustained inhibition on intracellular amastigote replication, compound 3 is the best candidate to be tested in vivo. This compound is worth considering for the development of new antileishmanial drugs., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

With the purpose of studying the antigenic role that factors excreted by Leishmania amastigotes might have during murine infection, immunoblots were carried out with sera from C57BL/6 and BALB/c mice infected with two strains of Leishmania (L.) amazonensis, NR and IFLA/BR. Both strains differ widely in virulence in BALB/c mice. BALB/c but not C57BL/6 sera recognized several excretion products. The excreted antigens showed a strong response towards IgG1 and IgG2a isotypes whilst they reacted only weakly against IgG2b and IgG3. A low-molecular weight antigen (about 20 kDa) excreted by both Leishmania strains was strongly recognized by IgG1 from BALB/c mice sera infected with IFLA/BR, the most virulent strain. Sera from NR infected mice were incapable of recognizing this antigen in spite of its presence in NR excreted products. The results indicate that the humoral immune response to excreted antigens of amastigotes depends on both the host genetic background and the parasite strain.

We report the successful removal of a severed and impacted Dormia basket from an elderly patient with choledocholithiasis. One aspect of the case that increased its difficulty is that the basket had become trapped in the bile duct by attaching to an immobile stone that had formed on suture material from a prior biliary operation. Severed baskets that become entrapped in the bile duct are unusual complications of endoscopic bile duct stone removal which used to require surgical intervention. More recent reports suggest that retained baskets can be removed endoscopically in conjunction with some form of lithotripsy. The method used to remove the retained basket in our case involved advancing a Soehendra lithotripter over a looped guidewire after first shrinking the stone with extracorporeal shock wave and laser lithotripsy.