Discovery and optimization of 3-(4-aryl/heteroarylsulfonyl)piperazin-1-yl)-6-(piperidin-1-yl)pyridazines as novel,CNS penetrant pan-muscarinic antagonists

This letter describes the synthesis and structure activity relationship (SAR) studies of structurally novel M₄ antagonists, based on a 3-(4-aryl/heteroarylsulfonyl)piperazin-1-yl)-6-(piperidin-1-yl)pyridazine core, identified from a high-throughput screening campaign. A multi-dimensional optimization effort enhanced potency at human M₄ (hM₄ IC₅₀s < 200 nM), with only moderate species differences noted, and with enantioselective inhibition. Moreover, CNS penetration proved attractive for this series (rat brain:plasma K_p = 2.1, K_p,uu = 1.1). Despite the absence of the prototypical mAChR antagonist basic or quaternary amine moiety, this series displayed pan-muscarinic antagonist activity across M_1-5 (with 9- to 16-fold functional selectivity at best). This series further expands the chemical diversity of mAChR antagonists.     

Efficacy of a New Educational Tool to Improve Handrubbing Technique amongst Healthcare Workers: A Controlled,Before-After Study

Introduction

Hand hygiene is a key component of infection control in healthcare. WHO recommends that healthcare workers perform six specific poses during each hand hygiene action. SureWash (Glanta Ltd, Dublin, Ireland) is a novel device that uses video-measurement technology and immediate feedback to teach this technique. We assessed the impact of self-directed SureWash use on healthcare worker hand hygiene technique and evaluated the device''s diagnostic capacity.

Methods

A controlled before-after study: subjects in Group A were exposed to the SureWash for four weeks followed by Group B for 12 weeks. Each subject''s hand hygiene technique was assessed by blinded observers at baseline (T₀) and following intervention periods (T₁ and T₂). Primary outcome was performance of a complete hand hygiene action, requiring all six poses during an action lasting ≥20 seconds. The number of poses per hand hygiene action (maximum 6) was assessed in a post-hoc analysis. SureWash''s diagnostic capacity compared to human observers was assessed using ROC curve analysis.

Results

Thirty-four and 29 healthcare workers were recruited to groups A and B, respectively. No participants performed a complete action at baseline. At T₁, one Group A participant and no Group B participants performed a complete action. At baseline, the median number of poses performed per action was 2.0 and 1.0 in Groups A and B, respectively (p = 0.12). At T₁, the number of poses per action was greater in Group A (post-intervention) than Group B (control): median 3.8 and 2.0, respectively (p<0.001). In Group A, the number of poses performed twelve weeks post-intervention (median 3.0) remained higher than baseline (p<0.001). The area under the ROC curves for the 6 poses ranged from 0.59 to 0.88.

Discussion

While no impact on complete actions was demonstrated, SureWash significantly increased the number of poses per hand hygiene action and demonstrated good diagnostic capacity.     

Assessment of the Incremental Benefit of Computer-Aided Detection (CAD) for Interpretation of CT Colonography by Experienced and Inexperienced Readers

Objectives

To quantify the incremental benefit of computer-assisted-detection (CAD) for polyps, for inexperienced readers versus experienced readers of CT colonography.

Methods

10 inexperienced and 16 experienced radiologists interpreted 102 colonography studies unassisted and with CAD utilised in a concurrent paradigm. They indicated any polyps detected on a study sheet. Readers’ interpretations were compared against a ground-truth reference standard: 46 studies were normal and 56 had at least one polyp (132 polyps in total). The primary study outcome was the difference in CAD net benefit (a combination of change in sensitivity and change in specificity with CAD, weighted towards sensitivity) for detection of patients with polyps.

Results

Inexperienced readers’ per-patient sensitivity rose from 39.1% to 53.2% with CAD and specificity fell from 94.1% to 88.0%, both statistically significant. Experienced readers’ sensitivity rose from 57.5% to 62.1% and specificity fell from 91.0% to 88.3%, both non-significant. Net benefit with CAD assistance was significant for inexperienced readers but not for experienced readers: 11.2% (95%CI 3.1% to 18.9%) versus 3.2% (95%CI -1.9% to 8.3%) respectively.

Conclusions

Concurrent CAD resulted in a significant net benefit when used by inexperienced readers to identify patients with polyps by CT colonography. The net benefit was nearly four times the magnitude of that observed for experienced readers. Experienced readers did not benefit significantly from concurrent CAD.     

Ontogenetic shift in diet of a large elapid snake is facilitated by allometric change in skull morphology

Evolutionary Ecology - As snakes are limbless, gape-limited predators, their skull is the main feeding structure involved in prey handling, manipulation and feeding. Ontogenetic changes in prey...     

Functional analysis of lipid metabolism in Magnaporthe grisea reveals a requirement for peroxisomal fatty acid beta-oxidation during appressorium-mediated plant infection

The rice blast fungus Magnaporthe grisea infects plants by means of specialized infection structures known as appressoria. Turgor generated in the appressorium provides the invasive force that allows the fungus to breach the leaf cuticle with a narrow-penetration hypha gaining entry to the underlying epidermal cell. Appressorium maturation in M. grisea involves mass transfer of lipid bodies to the developing appressorium, coupled to autophagic cell death in the conidium and rapid lipolysis at the onset of appressorial turgor generation. Here, we report identification of the principal components of lipid metabolism in M. grisea based on genome sequence analysis. We show that deletion of any of the eight putative intracellular triacylglycerol lipase-encoding genes from the fungus is insufficient to prevent plant infection, highlighting the complexity and redundancy associated with appressorial lipolysis. In contrast, we demonstrate that a peroxisomally located multifunctional, fatty acid beta-oxidation enzyme is critical to appressorium physiology, and blocking peroxisomal biogenesis prevents plant infection. Taken together, our results indicate that, although triacylglycerol breakdown in the appressorium involves the concerted action of several lipases, fatty acid metabolism and consequent generation of acetyl CoA are necessary for M. grisea to complete its prepenetration phase of development and enter the host plant.     

PRODUCTION AND CELLULAR LOCALIZATION OF NEUTRAL LONG‐CHAIN LIPIDS IN THE HAPTOPHYTE ALGAE ISOCHRYSIS GALBANA AND EMILIANIA HUXLEYI1

Isochrysis galbana Parke, Emiliania huxleyi (Lohm.) Hay and Mohler, and some related prymnesiophyte algae produce as neutral lipids a set of polyunsaturated long‐chain (C_37–39) alkenones, alkenoates, and alkenes (PULCA). These biomarkers are widely used for paleothermometry, but the biosynthesis and cellular location of these unique lipids remain largely unknown. By staining with the fluorescent lipophilic dye Nile Red, we found that I. galbana and E. huxleyi, like many other algae, package their neutral lipid into cytoplasmic vesicles or lipid bodies. We found that these lipid bodies increase in abundance under nutrient limitation and disappear under prolonged darkness and show that this pattern correlates well with the concentration of PULCA as measured by TLC. In addition, we show that lipid vesicles purified by sucrose density gradient centrifugation consist predominantly of PULCA. We also found significant pools of neutral lipid associated with chloroplasts, and PULCA component profiles in lipid vesicles and chloroplasts are similar. Examination of cell ultrastructure shows conspicuous cytoplasmic and chloroplast lipid bodies, and we suggest that PULCA may be synthesized in chloroplasts and then exported to cytoplasmic lipid bodies for storage and eventual metabolism. Our results connect and extend prior observations of lipid bodies and membrane‐unbound PULCA in I. galbana and E. huxleyi, as well as the behavior of PULCA during nutrient and light stress.     

Recent Advances in CRISPR‐Cas9 Genome Editing Technology for Biological and Biomedical Investigations

The Type II CRISPR‐Cas9 system is a simple, efficient, and versatile tool for targeted genome editing in a wide range of organisms and cell types. It continues to gain more scientific interest and has established itself as an extremely powerful technology within our synthetic biology toolkit. It works upon a targeted site and generates a double strand breaks that become repaired by either the NHEJ or the HDR pathway, modifying or permanently replacing the genomic target sequences of interest. These can include viral targets, single‐mutation genetic diseases, and multiple‐site corrections for wide scale disease states, offering the potential to manage and cure some of mankind's most persistent biomedical menaces. Here, we present the developing progress and future potential of CRISPR‐Cas9 in biological and biomedical investigations, toward numerous therapeutic, biomedical, and biotechnological applications, as well as some of the challenges within. J. Cell. Biochem. 119: 81–94, 2018. © 2017 Wiley Periodicals, Inc.     

Multidirectional differentiation in neuroendocrine neoplasms

Histopathological and experimental observations indicate that tumors composed wholly or in part of neuroendocrine elements may arise in tissues derived from ectoderm (including neuroectoderm), mesoderm, and endoderm. These tumors frequently exhibit multidirectional differentiation as manifested by multihormonality and by the presence of morphological features indicative of divergent differentiation both in vivo and in vitro. The existence of stem cells, plasticity of differentiated cells, microenvironmental influences, and random events are factors which might all interact to determine the characteristics of any particular tumor. The production of characteristic regulatory peptide products in association with tumors of specific histological subtypes and with other neuroendocrine markers suggests mechanisms for nonrandom activation of multiple genes common to neuroendocrine-programmed cells. Future studies applying new molecular biological techniques to intact tissues and to in vitro models may help to clarify the mechanisms that regulate the expression of the neuroendocrine phenotype in normal and neoplastic states.     

Opt-Out Panel Testing for HIV,Hepatitis B and Hepatitis C in an Urban Emergency Department: A Pilot Study

Objectives

Studies suggest 2 per 1000 people in Dublin are living with HIV, the level above which universal screening is advised. We aimed to assess the feasibility and acceptability of a universal opt-out HIV, Hepatitis B and Hepatitis C testing programme for Emergency Department patients and to describe the incidence and prevalence of blood-borne viruses in this population.

Methods

An opt-out ED blood borne virus screening programme was piloted from March 2014 to January 2015. Patients undergoing blood sampling during routine clinical care were offered HIV 1&2 antibody/antigen assay, HBV surface antigen and HCV antibody tests. Linkage to care where necessary was co-ordinated by the study team. New diagnosis and prevalence rates were defined as the new cases per 1000 tested and number of positive tests per 1000 tested respectively.

Results

Over 45 weeks of testing, of 10,000 patient visits, 8,839 individual patient samples were available for analysis following removal of duplicates. A sustained target uptake of >50% was obtained after week 3. 97(1.09%), 44(0.49%) and 447(5.05%) HIV, Hepatitis B and Hepatitis C tests were positive respectively. Of these, 7(0.08%), 20(0.22%) and 58(0.66%) were new diagnoses of HIV, Hepatitis B and Hepatitis C respectively. The new diagnosis rate for HIV, Hepatitis B and Hepatitis C was 0.8, 2.26 and 6.5 per 1000 and study prevalence for HIV, Hepatitis B and Hepatitis C was 11.0, 5.0 and 50.5 per 1000 respectively.

Conclusions

Opt-out blood borne viral screening was feasible and acceptable in an inner-city ED. Blood borne viral infections were prevalent in this population and newly diagnosed cases were diagnosed and linked to care. These results suggest widespread blood borne viral testing in differing clinical locations with differing population demographic risks may be warranted.