Total absence of protein 4.2 and partial deficiency of band 3 in hereditary spherocytosis

Unlike previously reported cases with total protein 4.2 deficiency due to mutations in the EPB42 gene, we describe a total deficiency in protein 4.2 with normal EPB42 alleles. Hereditary spherocytosis (HS) was observed in a Japanese woman (unsplenectomized) and her daughter (splenectomized). The mother showed a partial deficiency in band 3 and a proportional reduction in protein 4.2. She was heterozygous for a novel allele of the EPB3 gene, allele Okinawa, which contains the two mutations that define the Memphis II polymorphism (K56E, AAG → GAG, and P854L, CCG → CTG) and, additionally, the mutation: G714R, GGG → AGG, located in a highly conserved position of transmembrane segment 9. The latter change was responsible for HS. In trans to allele Okinawa, the daughter displayed allele Fukuoka: G130R, GGA → AGA, an allele known to alter the binding of protein 4.2 to band 3. The daughter presented with a more pronounced decrease of band 3, and lacked protein 4.2, resulting in aggravated haemolytic features. Although the father was not available for study, heterozygosity for allele Fukuoka has been documented in another individual who showed no clinical or haematological signs, and a normal content of band 3. We suggest that band 3 Okinawa binds virtually all the protein 4.2 in red cell precursors, band 3 Fukuoka being unable to do so, and that the impossibility of band 3 Okinawa incorporation into the membrane leads to degradation of the band 3 Okinawa protein 4.2 complex. In contrast, band 3 Fukuoka, free of bound protein 4.2, could then incorporate normally into the bilayer. Thus, protein 4.2 would not appear in the daughter's red cell membrane.     

A case of hepatic alveolar echinococcosis contracted in Belgium

We report herein the case of a Belgian 76-year-old woman who developed a hepatic tumour suspected to be a breast cancer metastasis. Radiological imaging and guided biopsies were not contributive. The patient underwent an explorative laparoscopy with frozen sections that did not provide further diagnosis, and an open left bisegmentectomy was performed during the same anaesthesia. Histopathological examination of the hepatic mass showed Echinococcus multilocularis metacestodes, demonstrating alveolar echinococcosis. As our patient denied any travel in foreign countries and has undergone regular abdominal ultrasonographies since her mastectomy, it is highly likely that this alveolar echinococcosis had been contracted in Belgium. If some imported cases may be seldom managed in Belgium, to our knowledge, this case is the first occurrence of alveolar echinococcosis contracted in Belgium. This report, added to the demonstration of E. multilocaris infection of 50% of red foxes in Southern Belgium, and the potential infection of domestic cats and dogs, should attract attention of the medical community on the possible outbreak of endemic alveolar echinococcosis in Belgium, and on the related public health concerns.     

Strychnogucines A and B, two new antiplasmodial bisindole alkaloids from Strychnos icaja

A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by means of spectroscopic data interpretation. Compound 2 was highly active in vitro and compound 1 moderately active against four strains of Plasmodium falciparum. Strychnogucine B (2) was more active against a chloroquine-resistant strain than against a chloroquine-sensitive one (best CI(50), 80 nM against the W2 strain). In addition, this compound showed a selective antiplasmodial activity with 25-180 times greater toxicity toward P. falciparum, relative to cultured human cancer cells (KB) or human fibroblasts (WI38).     

New antimalarial and cytotoxic sungucine derivatives from Strychnos icaja roots

Reinvestigation of Strychnos icaja Baillon resulted in the isolation of vomicine, isostrychnine and of three new sungucine derivatives, named isosungucine (8), 18-hydroxy-sungucine (9) and 18-hydroxy-isosungucine (10). They were identified by detailed spectroscopic methods. The complete 1H- and 13C-NMR study of sungucine was also realized. Some of these compounds were highly active against Plasmodium falciparum in vitro and more particularly against the chloroquine-resistant strain. Compound 10 showed a selective antiplasmodial activity, with > 100-fold greater toxicity towards Plasmodium falciparum, relative to cultured human cancer cells (KB and HeLa lines) or fibroblasts (WI38).     

Cholesterol crystallization in human atherosclerosis is triggered in smooth muscle cells during the transition from fatty streak to fibroatheroma

Recent studies have shown that in addition to being major constituents of the atheromatous core, solid cholesterol crystals (CCs) promote atherosclerotic lesion development and rupture by causing mechanical damage and exerting cytotoxic and pro‐inflammatory effects. These findings suggest that targeting CCs might represent a therapeutic strategy for plaque stabilization. However, little is known about how cholesterol crystallization is initiated in human atherothrombotic disease. Here, we investigated these mechanisms. We performed a thorough immunohistological analysis of non‐embedded, minimally processed human aortic tissues, combining polarized light and fluorescence microscopy. We found that CC formation was initiated during the fatty streak to fibroatheroma transition in tight association with the death of intralesional smooth muscle cells (SMCs). Cholesterol‐loaded human SMCs were capable of producing CCs in vitro, a process that was enhanced by type I collagen and by inhibition of autophagy and cholesterol esterification. The fibrous transition, which was characterized by increased type I collagen expression, was associated with changes in the expression of autophagy and cholesterol flux‐related genes, including a decrease in the autophagic adapter p62 and an increase in the cholesterol intracellular transporter Niemann–Pick C1. Collagen was identified as a potent inducer of these changes in SMCs. Collagen‐induced changes in cholesterol metabolism and autophagy flux in smooth muscle foam cells at the fibrolipid transition likely contribute to initiate cholesterol crystallization in human atherosclerosis. Also, our data are in support of a protective role of autophagy against CC formation. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Plasmid-mediated florfenicol resistance in Pasteurella trehalosi

OBJECTIVES: A florfenicol-resistant Pasteurella trehalosi isolate from a calf was investigated for the presence and the location of the gene floR. METHODS: The P. trehalosi isolate 13698 was investigated for its in vitro susceptibility to antimicrobial agents and its plasmid content. A 14.9 kb plasmid, designated pCCK13698, was identified by transformation into Pasteurella multocida to mediate resistance to florfenicol, chloramphenicol and sulphonamides. The plasmid was sequenced completely and analysed for its structure and organization. RESULTS: Plasmid pCCK13698 exhibited extended similarity to plasmid pHS-Rec from Haemophilus parasuis including the region carrying the parA, repB, rec and int genes. Moreover, it revealed similarities to plasmid RSF1010 in the parts covering the mobC and repA-repC genes and to plasmid pMVSCS1 in the parts covering the sul2-catA3-strA gene cluster. Moreover, the floR gene area corresponded to that of transposon TnfloR. In addition, two complete insertion sequences were detected that were highly similar to IS1593 from Mannheimia haemolytica and IS26 from Enterobacteriaceae. Several potential recombination sites were identified that might explain the development of plasmid pCCK13698 by recombination events. CONCLUSIONS: The results of this study showed that in the bovine pathogen P. trehalosi, floR-mediated resistance to chloramphenicol and florfenicol was associated with a plasmid, which also carried functionally active genes for resistance to sulphonamides (sul2) and chloramphenicol (catA3). This is to the best of our knowledge the first report of resistance genes in P. trehalosi and only the second report of the presence of a florfenicol-resistance gene in target bacteria of the family Pasteurellaceae.     

Liver fibrosis regression and progression during controlled hepatitis B virus infection among HIV–HBV patients treated with tenofovir disoproxil fumarate in France: a prospective cohort study

Introduction : Long‐term tenofovir disoproxil fumarate (TDF) use has been associated with significant regression of liver fibrosis during hepatitis B virus (HBV) mono‐infection, yet little is known during HIV–HBV coinfection. The aim of this study was to evaluate the evolution of liver fibrosis and its determinants in TDF‐treated coinfected patients. Methods : In this prospective cohort study, 167 HIV–HBV‐infected patients initiating TDF‐containing antiretroviral therapy were included. Fibrosis was assessed using the FibroTest® at baseline and every six to twelve months. Risk factors for fibrosis progression (F0–F1–F2 to F3–F4) and regression (F3–F4 to F0–F1–F2) were evaluated. Results : At baseline, 134 (80.2%) patients had detectable HBV‐DNA (median = 4.93 log₁₀ IU/mL, IQR = 2.94–7.15) and 104 (62.3%) had hepatitis B “e” antigen‐positive serology. Median follow‐up was sixty months (IQR = 36–93). In the 47 (28.1%) patients with F3–F4 baseline fibrosis, 7/47 (14.9%) regressed to F0–F1–F2 at last follow‐up visit. Fibrosis regression was significantly associated with higher CD4+ cell counts (P = 0.009) and lower fasting triglyceride levels (P = 0.007) at TDF‐initiation. In the 120 (71.9%) patients with F0–F1–F2‐baseline fibrosis, 20/120 (16.7%) progressed to F3–F4 at last follow‐up visit. Fibrosis progression was associated with male gender (P = 0.01), older age (P = 0.001), from low/moderate HBV‐endemic country (P = 0.007), lower nadir CD4+ cell count (P = 0.03), higher fasting glycaemia (P = 0.03) and anaemia (P = 0.004) at TDF‐initiation. Control of HBV replication at end of follow‐up was extensive (88.1%), while no HBV‐related factors emerged as predictors of progression/regression. Incidence of severe liver‐related events was low (n = 4, rate = 0.5/100 person‐years). Conclusions : Liver fibrosis levels are stable for most coinfected patients undergoing TDF, despite control of HBV replication. Nevertheless, a concerning amount of liver fibrosis progression did occur, which could be partly explained by metabolic abnormalities and past severe immunosuppression and requires further evaluation.