Next-generation neuropeptide Y receptor small-molecule agonists inhibit mosquito-biting behavior.

BACKGROUND: Female Aedes aegypti mosquitoes can spread disease-causing pathogens when they bite humans to obtain blood nutrients required for egg production. Following a complete blood meal, host-seeking is suppressed until eggs are laid. Neuropeptide Y-like receptor 7 (NPYLR7) plays a role in endogenous host-seeking suppression and previous work identified small-molecule NPYLR7 agonists that inhibit host-seeking and blood-feeding when fed to mosquitoes at high micromolar doses. METHODS: Using structure-activity relationship analysis and structure-guided design we synthesized 128 compounds with similarity to known NPYLR7 agonists. RESULTS: Although in vitro potency (EC50) was not strictly predictive of in vivo effect, we identified three compounds that reduced blood-feeding from a live host when fed to mosquitoes at a dose of 1 µM-a 100-fold improvement over the original reference compound. CONCLUSIONS: Exogenous activation of NPYLR7 represents an innovative vector control strategy to block mosquito biting behavior and prevent mosquito-human host interactions that lead to pathogen transmission.

Lead Optimization of Small Molecule ENL YEATS Inhibitors to Enable In Vivo Studies: Discovery of TDI-11055.

Eleven-nineteen leukemia (ENL) is an epigenetic reader protein that drives oncogenic transcriptional programs in acute myeloid leukemia (AML). AML is one of the deadliest hematopoietic malignancies, with an overall 5-year survival rate of 27%. The epigenetic reader activity of ENL is mediated by its YEATS domain that binds to acetyl and crotonyl marks on histone tails and colocalizes with promoters of actively transcribed genes that are essential for leukemia. Prior to the discovery of TDI-11055, existing inhibitors of ENL YEATS showed in vitro potency, but had not shown efficacy in in vivo animal models. During the course of the medicinal chemistry campaign described here, we identified ENL YEATS inhibitor TDI-11055 that has an improved pharmacokinetic profile and is appropriate for in vivo evaluation of the ENL YEATS inhibition mechanism in AML.

Next Generation Neuropeptide Y Receptor Small Molecule Agonists Inhibit Mosquito Biting Behavior.

Female Aedes aegypti mosquitoes can spread disease-causing pathogens when they bite humans to obtain blood nutrients required for egg production. Following a complete blood meal, host-seeking is suppressed until eggs are laid. Neuropeptide Y-like Receptor 7 (NPYLR7) plays a role in endogenous host-seeking suppression and previous work identified small molecule NPYLR7 agonists that suppress host-seeking and blood feeding when fed to mosquitoes at high micromolar doses. Using structure activity relationship analysis and structure-guided design we synthesized 128 compounds with similarity to known NPYLR7 agonists. Although in vitro potency (EC50) was not strictly predictive of in vivo effect, we identified 3 compounds that suppressed blood feeding from a live host when fed to mosquitoes at a 1 µM dose, a 100-fold improvement over the original reference compound. Exogenous activation of NPYLR7 represents an innovative vector control strategy to block mosquito biting behavior and prevent mosquito/human host interactions that lead to pathogen transmission.

Small-Molecule Inhibition of the Acyl-Lysine Reader ENL as a Strategy against Acute Myeloid Leukemia.

The chromatin reader eleven-nineteen leukemia (ENL) has been identified as a critical dependency in acute myeloid leukemia (AML), but its therapeutic potential remains unclear. We describe a potent and orally bioavailable small-molecule inhibitor of ENL, TDI-11055, which displaces ENL from chromatin by blocking its YEATS domain interaction with acylated histones. Cell lines and primary patient samples carrying MLL rearrangements or NPM1 mutations are responsive to TDI-11055. A CRISPR-Cas9-mediated mutagenesis screen uncovers an ENL mutation that confers resistance to TDI-11055, validating the compound's on-target activity. TDI-11055 treatment rapidly decreases chromatin occupancy of ENL-associated complexes and impairs transcription elongation, leading to suppression of key oncogenic gene expression programs and induction of differentiation. In vivo treatment with TDI-11055 blocks disease progression in cell line- and patient-derived xenograft models of MLL-rearranged and NPM1-mutated AML. Our results establish ENL displacement from chromatin as a promising epigenetic therapy for molecularly defined AML subsets and support the clinical translation of this approach. SIGNIFICANCE: AML is a poor-prognosis disease for which new therapeutic approaches are desperately needed. We developed an orally bioavailable inhibitor of ENL, demonstrated its potent efficacy in MLL-rearranged and NPM1-mutated AML, and determined its mechanisms of action. These biological and chemical insights will facilitate both basic research and clinical translation. This article is highlighted in the In This Issue feature, p. 2483.

Upper Eyelid Reconstruction Surgeries; Comparison Of Outcomes Between Reverse Tenzel Flap Versus Cutler Beard Flap Procedure.

BACKGROUND: Objective of this study was to compare Reverse Tenzel flap and Cutler Beard flap for upper eyelid defects. METHODS: This interventional study was carried out at occuloplasty department of LRBT (Layton Rahamatullah Benevoloent Trust), Karachi. Patients diagnosed with upper eye lid defect between 50 and 75 years were included after ethical approval from institutional ethical review committee and briefing patients about study dynamics. The patients were randomly divided in two groups, group A in whom reverse tanzel flap was done, while in group B Cutler beard procedure was done. Main outcome measure was eyelid contour, complete lid closure and surgical procedure time. SPSS version 25.0 was used for data analysis. RESULTS: Reverse Tenzel flap mean age 64.00±6.17 years, mean duration of surgery 33±5.78 minutes, and mean healing time 2.2±0.41 weeks. Cutler Beard flap mean age 59.60±6.26 years, mean duration of surgery 32±5.78 minutes, and mean healing time 5.7±0.8 in 3 weeks. 60% of patients were female. 30 (50%) patients each underwent Reverse Tenzel flap and Cutler Beard flap. In Reverse Tenzel flap, no complications were observed. In Cutler Beard flap, 06 (20%) patients reported mild entropion, 04 (13.3%) retraction of flap and 02 (6.7%) were found to have mild incomplete lid closure. CONCLUSIONS: Reverse Tenzel flap was superior to Cutler Beard flap as it reported no complications, being single stage surgery with early healing. Cutler-Beard flap reported mild entropion and retraction of flaps which required second surgery and delayed healing.

Treatment of Chronic Large and Persistent Macular Hole by a new technique in a Tertiary Care Hospital.

OBJECTIVE: To assess the anatomical and functional outcomes of treating chronic persistent large macular hole by macular hole hydrodissection technique in a tertiary eye care hospital. METHODS: This interventional case series study was conducted in the Vitreoretinal department of LRBT Tertiary Teaching Eye Hospital, Karachi, from October 2017 to March 2018, with follow-ups till February 2019. The study included eighteen cases of chronic (symptoms of loss of central vision ≥ 2years), persistent (previously failed macular hole surgery), large (aperture diameter of ≥ 400µm) macular hole. Out of the eighteen patients, eight (44.4%) were males and ten (55.6%) were females. All operated patients underwent macular hole hydrodissection by balanced salt solution using a silicone soft tip extrusion cannula. Patients were followed up post operatively to assess post-operative complications and surgical results. RESULTS: Among eighteen patients with a mean aperture diameter of 477.1±102.9 µm and basal diameter of 849.4± 92.6µm, complete anatomical closure was achieved in sixteen (88.8%). Five (27.7%) out of the eighteen patients achieved best corrected visual acuity improvement of 6/36, whereas seven (38.8%) patients reached up to a BCVA of 6/60, with maximum improvement of two lines. The mean post-operative follow-up was 332.3± 46.7 days. CONCLUSION: Macular hole hydrodissection is a relatively new emerging technique with promising results for the closure of chronic persistent large macular hole.

Role of Concomitant Internal Limiting Membrane (ILM) Peeling During Rhegmatogenous Retinal Detachment (RRD) Surgery in Preventing Postoperative Epiretinal Membrane (ERM) Formation.

OBJECTIVE: To investigate the role of concomitant Internal Limiting Membrane (ILM) peeling during surgery for macula off Rhegmatogenous Retinal Detachment (RRD) in preventing postoperative Epiretinal Membrane (ERM) formation; and its effect on the visual acuity. METHODS: This was a prospective, quasi-experimental study conducted from August 2018 to July 2019 at LRBT Tertiary Eye Care hospital, Karachi. Fifty-six patients with macula off RRD were divided into groups A (with ILM peeling) and B (without ILM peeling) via non-probability convenience sampling. All patients underwent standard 3 ports pars plana vitrectomy with silicon oil tamponade. In Group-A, ILM was stained using 0.5% ICG. Patients were evaluated clinically and by spectral domain optical coherence tomography (SD-OCT), pre- and post-operatively. Main outcomes recorded were best corrected visual acuity (BCVA) and occurrence of ERM on SD-OCT. RESULTS: There were 26 patients in Group-A and 30 patients in Group-B. At six months' follow-up, ERM had not developed in any case in Group-A compared to five patients (16.7%) in Group-B. There was no statistical difference in mean BCVA change from baseline. CONCLUSION: ILM peeling during vitrectomy for RRD prevents the formation of macular ERM post-operatively. This may reduce the need of a second vitrectomy. However, visual outcomes were comparable to the non-ILM peeling vitrectomy.

Dual Plasmepsin-Targeting Antimalarial Agents Disrupt Multiple Stages of the Malaria Parasite Life Cycle.

Artemisin combination therapy (ACT) is the main treatment option for malaria, which is caused by the intracellular parasite Plasmodium. However, increased resistance to ACT highlights the importance of finding new drugs. Recently, the aspartic proteases Plasmepsin IX and X (PMIX and PMX) were identified as promising drug targets. In this study, we describe dual inhibitors of PMIX and PMX, including WM382, that block multiple stages of the Plasmodium life cycle. We demonstrate that PMX is a master modulator of merozoite invasion and direct maturation of proteins required for invasion, parasite development, and egress. Oral administration of WM382 cured mice of P. berghei and prevented blood infection from the liver. In addition, WM382 was efficacious against P. falciparum asexual infection in humanized mice and prevented transmission to mosquitoes. Selection of resistant P. falciparum in vitro was not achievable. Together, these show that dual PMIX and PMX inhibitors are promising candidates for malaria treatment and prevention.

Synthesis of amino heterocycle aspartyl protease inhibitors.

Aspartyl proteases are important pharmacological targets. Historically aspartyl proteases have been commonly targeted with transition state derived peptidomimetics. The strategy to develop aspartyl protease inhibitors has undertaken a dramatic paradigm shift in the last 10 years. The pharmaceutical industry in 2005 disclosed several scaffolds or "head groups" that prompted the field to move beyond peptidomimetic derived inhibitors. Since the discovery of the first amino heterocycle aspartyl protease inhibitor, the amino hydantoin, industry and academia have positioned themselves for a foothold on the new molecular space, designing a variety of related "head groups". Both the design and synthetic efforts involved in constructing these scaffolds are varied and complex. Here we highlight the synthetic strategies used to access these amino heterocycle scaffolds.

Discovery of aminoquinazoline derivatives as human A(2A) adenosine receptor antagonists.

Novel bicyclic adenosine A(2A) antagonists with an aminoquinazoline moiety were designed and synthesized. The optimization of the initial lead compound based on in vitro and in vivo activity has led to the discovery of a potent and selective class of adenosine A(2A) antagonists. The structure-activity relationships of this novel series of bicyclic aminoquinazoline derivatives as adenosine A(2A) antagonists are described in detail.

Iminopyrimidinones: a novel pharmacophore for the development of orally active renin inhibitors.

The development of renin inhibitors with favorable oral pharmacokinetic profiles has been a longstanding challenge for the pharmaceutical industry. As part of our work to identify inhibitors of BACE1, we have previously developed iminopyrimidinones as a novel pharmacophore for aspartyl protease inhibition. In this letter we describe how we modified substitution around this pharmacophore to develop a potent, selective and orally active renin inhibitor.

Cultured representatives of two major phylogroups of human colonic Faecalibacterium prausnitzii can utilize pectin, uronic acids, and host-derived substrates for growth.

Faecalibacterium prausnitzii is one of the most abundant commensal bacteria in the healthy human large intestine, but information on genetic diversity and substrate utilization is limited. Here, we examine the phylogeny, phenotypic characteristics, and influence of gut environmental factors on growth of F. prausnitzii strains isolated from healthy subjects. Phylogenetic analysis based on the 16S rRNA sequences indicated that the cultured strains were representative of F. prausnitzii sequences detected by direct analysis of fecal DNA and separated the available isolates into two phylogroups. Most F. prausnitzii strains tested grew well under anaerobic conditions on apple pectin. Furthermore, F. prausnitzii strains competed successfully in coculture with two other abundant pectin-utilizing species, Bacteroides thetaiotaomicron and Eubacterium eligens, with apple pectin as substrate, suggesting that this species makes a contribution to pectin fermentation in the colon. Many F. prausnitzii isolates were able to utilize uronic acids for growth, an ability previously thought to be confined to Bacteroides spp. among human colonic anaerobes. Most strains grew on N-acetylglucosamine, demonstrating an ability to utilize host-derived substrates. All strains tested were bile sensitive, showing at least 80% growth inhibition in the presence of 0.5 µg/ml bile salts, while inhibition at mildly acidic pH was strain dependent. These attributes help to explain the abundance of F. prausnitzii in the colonic community but also suggest factors in the gut environment that may limit its distribution.

Novel phosphorus radical-based routes to horsfiline.

[reaction: see text]. Radicals derived from the phosphorus reagents, ethylpiperidine hypophosphite (EPHP) and diethylphosphine oxide (DEPO), are used in two related approaches to synthesis of the alkaloid horsfiline (1). In particular, DEPO proves beneficial for effecting cyclizations at 80 degrees C that are difficult or impossible with Bu(3)SnH.

Direct conversion of N-methoxy-N-methylamides (Weinreb amides) to ketones via a nonclassical Wittig reaction.

[reaction: see text] N-Methoxy-N-methylamides (Weinreb amides) are converted efficiently into ketones by reaction with alkylidenetriphenylphosphoranes and in situ hydrolysis of the product.

Diethylphosphine oxide (DEPO): high-yielding and facile preparation of indolones in water.

[reaction: see text] Indolones are prepared in excellent yield at 80 degrees C in water by radical reaction (aryl radical formation, hydrogen atom abstraction, cyclization, and rearomatization) mediated by the reagent diethylphosphine oxide (DEPO). The reaction features V-501 as a water-soluble initiator; no other additives are needed. The process proceeds at a much lower temperature than is required for efficient reaction with toxic tributyltin hydride in benzene and permits significantly higher isolated yields than the corresponding reaction mediated by ethylpiperidine hypophosphite (EPHP).