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Lymphoma is a blood cancer comprising various subtypes. Although effective therapies are available, some patients fail to respond to treatment and can suffer from side effects. Antioxidant systems, especially the thioredoxin (Trx) and glutathione (GSH) systems, are known to enhance cancer cell survival, with thioredoxin reductase (TrxR) recently reported as a potential anticancer target. Since the GSH system can compensate for some Trx system functions, we investigated its response in three lymphoma cell lines after inhibiting TrxR activity with [Au(d2pype)2]Cl, a known TrxR inhibitor. [Au(d2pype)2]Cl increased intracellular reactive oxygen species (ROS) levels and induced caspase-3 activity leading to cell apoptosis through inhibiting both TrxR and glutathione peroxidase (Gpx) activity. Expression of the tumour suppresser gene TXNIP increased, while GPX1 and GPX4 expression, which are related to poor prognosis of lymphoma patients, decreased. Unlike SUDHL2 and SUDHL4 cells, which exhibited a decreased GSH/GSSG ratio after treatment, in KMH2 cells the ratio remained unchanged, while glutathione reductase and glutaredoxin expression increased. Since KMH2 cells were less sensitive to treatment with [Au(d2pype)2]Cl, the GSH system may play a role in protecting cells from apoptosis after TrxR inhibition. Overall, our study demonstrates that inhibition of TrxR represents a valid therapeutic approach for lymphoma.

Tuberculosis and parasitic diseases, such as giardiasis, amebiasis, leishmaniasis, and trypanosomiasis, all urgently require improved treatment options. Recently, it has been shown that antitubercular bicyclic nitroimidazoles such as pretomanid and delamanid have potential as repurposed therapeutics for the treatment of visceral leishmaniasis. Here, we show that pretomanid also possesses potent activity against Giardia lamblia and Entamoeba histolytica, thus expanding the therapeutic potential of nitroimidazooxazines. Synthetic analogues with a novel nitroimidazopyrazin-one/-e bicyclic nitroimidazole chemotype were designed and synthesized, and structure–activity relationships were generated. Selected derivatives had potent antiparasitic and antitubercular activity while maintaining drug-like properties such as low cytotoxicity, good metabolic stability in liver microsomes and high apparent permeability across Caco-2 cells. The kinetic solubility of the new bicyclic derivatives varied and was found to be a key parameter for future optimization. Taken together, these results suggest that promising subclasses of bicyclic nitroimidazoles containing different core architectures have potential for further development.

Therapeutic treatment of tuberculosis (TB) is becoming increasingly problematic due to the emergence of drug resistant Mycobacterium tuberculosis (Mt). Thus, new targets for anti-TB drug discovery need to be identified to combat and eradicate this disease. One such target is hypoxanthine-guanine phosphoribosyltransferase (HGPRT) which synthesises the 6-oxopurine nucleoside monophosphates essential for DNA/RNA production. [3R,4R]-4-Hypoxanthin-9-yl-3-( (S)-2-hydroxy-2-phosphonoethyl)oxy-1-N-(phosphonopropionyl)pyrrolidine and [3R,4R-4-guanin-9-yl-3-((S)-2-hydroxy-2-phosphonoethyl)oxy-1-N-(phosphonopropionyl)pyrrolidine (compound 6) are the most potent inhibitors of MtHGPRT yet discovered having K-i values of 60 nM. The crystal structure of the MtHGPRT.6 complex was obtained and compared with that of human HGPRT in complex with the same inhibitor. These structures provide explanations for the 60-fold difference in the inhibition constants between these two enzymes and a foundation for the design of next generation inhibitors. In addition, crystal structures of MtHGPRT in complex with two pyrrolidine nucleoside phosphosphonate inhibitors plus pyrophosphate provide insights into the final stage of the catalytic reaction. As the first step in ascertaining if such compounds have the potential to be developed as anti-TB therapeutics, the tetra-(ethyl L-phenylalanine) tetraamide prodrug of 6 was tested in cell based assays. This compound arrested the growth of virulent Mt not only in its replicating phase (IC50 of 14 mu M) but also in its latent phase (IC50 of 29 mu M). Furthermore, it arrested the growth of Mt in infected macrophages (MIC50 of 85 mu M) and has a low cytotoxicity in mammalian cells (CC50 of 132 +/- 20 mu M). These inhibitors are therefore viewed as forerunners of new anti-TB chemotherapeutics. (C) 2018 Elsevier Masson SAS. All rights reserved.

Point mutations in DNA are useful biomarkers that can provide critical classification of disease for accurate diagnosis and to inform clinical decisions. Conventional approaches to detect point mutations are usually based on technologies such as real-time polymerase chain reaction (PCR) or DNA sequencing, which are typically slow and require expensive lab-based equipment. While rapid isothermal strategies such as recombinase polymerase amplification (RPA) have been proposed, they tend to suffer from poor specificity in discriminating point mutations. Herein, we describe a novel strategy that enabled exquisite point mutation discrimination with isothermal DNA amplification, using mismatched primers in conjunction with a two-round enrichment process. As a proof of concept, the method was applied to the rapid and specific identification of drug-resistant Mycobacterium tuberculosis using RPA under specific conditions. The assay requires just picogram levels of genomic DNA input, is sensitive and specific enough to detect 10% point mutation loading, and can discriminate between closely related mutant variants within 30 min. The assay was subsequently adapted onto a low-cost 3D-printed isothermal device with real-time analysis capabilities to demonstrate a potential point-of-care application. Finally, the generic applicability of the strategy was shown by detecting three other clinically important cancer-associated point mutations. We believe that our assay shows potential in a broad range of healthcare screening processes for detecting and categorizing disease phenotypes at the point of care, thus reducing unnecessary therapy and cost in these contexts.

Background Prior work using simulation for assessing intubation skills has largely focused on the use of observer-generated performance measures in the form of checklists and global ratings scales. Purpose The purpose of our work was to investigate whether patient-centered simulation data could be used to quantify learner's performance during direct laryngoscopy. Methods We designed a pretest/posttest prospective intervention study of residents' ( n = 25) intubation skills. Results When assessing validity, all of the patient-centered simulation variables showed significant correlations with the previously validated observer-generated performance measures (r = 0.331–0.463, P ≤ 0.001). When assessing reliability, there were significant correlations between all of the sensor variables, confirming moderate to high inter-item reliability (r = 0.259–0.794, P ≤ 0.05). The observer-generated performance measures showed significant improvement in use of the Macintosh blade (T1 = 2.10/5.00, T2 = 3.64/5.00, P = 0.001). However, this was not the case for the Miller blade (T1 = 1.30/5.00, T2 = 1.75/5.00, P = 0.119). Overall, the patient-centered simulation variables provided a high level of detail regarding performance improvement areas. Conclusion This study presents a multilevel analysis of sensor-generated simulation data. As the sensors provide sound, formative data regarding patient contact, the outputs may be used for specific criterion measures and detailed performance feedback.

Human tuberculosis is a chronic infectious disease affecting millions of lives. Because of emerging resistance to current medications, new therapeutic drugs are needed. One potential new target is hypoxanthine-guanine phosphoribosyltransferase (MtHGPRT), a key enzyme of the purine salvage pathway. Here, newly synthesized acyclic nucleoside phosphonates (ANPs) have been shown to be competitive inhibitors of MtHGPRT with Ki values as low as 0.69 μM. Prodrugs of these compounds arrest the growth of a virulent strain of M. tuberculosis with MIC50 values as low as 4.5 μM and possess low cytotoxicity in mammalian cells (CC50 values as high as >300 μM). In addition, the first crystal structures of MtHGPRT (2.03–2.76 A resolution) have been determined, three of these in complex with novel ANPs and one with GMP and pyrophosphate. These data provide a solid foundation for the further development of ANPs as selective inhibitors of MtHGPRT and as antituberculosis agents.

We introduced writing activities into a project style third year undergraduate biomolecular science laboratory to assist the students to produce a final report in the form of a journal article. To encourage writing while the experimental work was proceeding, the embedded writing activities required ongoing analysis of experimental data. After formative feedback from peers and teaching staff, the revised work was incorporated directly into the prepared journal framework. Surveys of student attitudes showed significant improvements in confidence in their ability to write an introduction, produce figure legends, distinguish results from discussion and generate a logical flow of information. Attitudes towards report writing became significantly more positive and the training was highly rated. Key factors that contributed to the perceived benefits were use of the student’s own data, the chance to incorporate revised work directly into their reports and the realisation that they were performing tasks of direct relevance to their future careers.

In this paper we describe how we fostered learning by modifying an existing course which covered topics relevant to biosciences. This course was offered predominantly to first year undergraduate science, biomedical science and environment students. The students were trained to find reliable scientific information via computer searches, and shown ways to use and cite references. Small teams of students used Internet resources to find, evaluate and summarise information for 15 minute presentations. An initial lack of confidence in presentation ability improved significantly over this period. The students identified the computer workshop format, the presentations and the interesting lectures as outstanding course features. The structure facilitated student-centred learning by providing interdisciplinary research topics that were considered interesting, relevant and authentic. The learning environment supported the diversity of abilities and interests of the students. Other positive student outcomes were the formation of friendships, a broadened interest in science, discovery of possible career paths, and greater confidence in their ability to find good references. The provision of computers with Internet access in the students' workshops changed the previously tutor-led approach to a student-centred format, ideal for ensuring active learning. The choice of interesting, multidisciplinary topics and lecturers also helped mitigate the possible negative effect of a student cohort drawn from diverse disciplines.

All solid organs contain resident monocyte-derived cells that appear early in organogenesis and persist throughout life. These cells are critical for normal development in some organs. Here we report the use of a previously described transgenic line, with EGFP driven by the macrophage-restricted Csf1r (c-fms) promoter, to image macrophage production and infiltration accompanying organogenesis in many tissues. Using microarray analysis of FACS-isolated EGFP-positive cells, we show that fetal kidney, lung and brain macrophages show similar gene expression profiles irrespective of their tissue of origin. EGFP-positive cells appeared in the renal interstitium from 12 days post coitum, prior to nephrogenesis, and maintain a close apposition to renal tubules postnatally. CSF-1 added to embryonic kidney explants increased overall renal growth and ureteric bud branching. Expression profiling of tissue macrophages and of CSF-1-treated explants showed evidence of the alternate, pro-proliferative (M2) activation profile, including expression of macrophage mannose receptor (CD206), macrophage scavenger receptor 2 (Msr2), C1q, CD163, selenoprotein P, CCL24 and TREM2. This response has been associated with the trophic role of tumour-associated macrophages. These findings suggest a trophic role of macrophages in embryonic kidney development, which may continue to play a similar role in postnatal repair.

The E11.5 mouse metanephros is comprised of a T-stage ureteric epithelial tubule sub-divided into tip and trunk cells surrounded by metanephric mesenchyme (MM). Tip cells are induced to undergo branching morphogenesis by the MM. In contrast, signals within the mesenchyme surrounding the trunk prevent ectopic branching of this region. In order to identify novel genes involved in the molecular regulation of branching morphogenesis we compared the gene expression profiles of isolated tip, trunk and MM cells using Compugen mouse long oligo microarrays. We identified genes enriched in the tip epithelium, sim-1, Arg2, Tacstd1, Crlf-1 and BMP7; genes enriched in the trunk epithelium, Innp1, Itm2b, Mkrn1, SPARC, Emu2 and Gsta3 and genes spatially restricted to the mesenchyme surrounding the trunk, CSPG2 and CV-2, with overlapping and complimentary expression to BMP4, respectively. This study has identified genes spatially expressed in regions of the developing kidney involved in branching morphogenesis, nephrogenesis and the development of the collecting duct system, calyces, renal pelvis and ureter.

In many instances, kidney dysgenesis results as a secondary consequence to defects in the development of the ureter. Through the use of mouse genetics a number of genes associated with such malformations have been identified, however, the cause of many other abnormalities remain unknown. In order to identify novel genes involved in ureter development we compared gene expression in embryonic day (E) 12.5, E15.5 and postnatal day (P) 75 ureters using the Compugen mouse long oligo microarrays. A total of 248 genes were dynamically upregulated and 208 downregulated between E12.5 and P75. At E12.5, when the mouse ureter is comprised of a simple cuboidal epithelium surrounded by ureteric mesenchyme, genes previously reported to be expressed in the ureteric mesenchyme, foxC1 and foxC2 were upregulated. By E15.5 the epithelial layer develops into urothelium, impermeable to urine, and smooth muscle develops for the peristaltic movement of urine towards the bladder. The development of these two cell types coincided with the upregulation of UPIIIa, RAB27b and PPARgamma reported to be expressed in the urothelium, and several muscle genes, Acta1, Tnnt2, Myocd, and Tpm2. In situ hybridization identified several novel genes with spatial expression within the smooth muscle, Acta1; ureteric mesenchyme and smooth muscle, Thbs2 and Col5a2; and urothelium, Kcnj8 and Adh1. This study marks the first known report defining global gene expression of the developing mouse ureter and will provide insight into the molecular mechanisms underlying kidney and lower urinary tract malformations.