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The design of potent indoleamine 2,3-dioxygenase 1 (IDOl) enzyme inhibitors targeting immunopathic neuroinflammation has emerged as an area of interest for the treatment of Alzheimer's disease (AD); additionally, recent findings on the clinical benefits of antibodies preventing [beta]-amyloid (Aft) aggregation have renewed efforts to discover small molecule anti-aggregants targeting proteopathic protein misfolding. Exploiting an endogenous tryptophan-like scaffold, we describe the design and synthesis of small-molecule inhibitors of both immunopathic and proteopathic processes, thus presenting the possibility of single therapeutics acting simultaneously on multiple AD pathogeneses. Specifically, investigations on compounds that inhibit both IDOl (in human recombinant enzyme, transfected HEK293 cells, and interferon-[gamma] stimulated human microglia assays) and Aft aggregation (in thioflavin-T and biotinylated-A[beta] oligomeric assays) are presented. Five compounds have been identified with high potency against both targets, identifying (E)-3-styryl indoles as useful tool compounds for developing Alzheimer's therapeutics. Brain penetration of these compounds via passive diffusion or active transport was predicted using Blood-Brain Barrier Score and Brain Exposure Efficiency Score calculations, respectively; the effects of efflux (pgp, BCRP), and influx (OCT1, OCT2) transporters were similarly predicted. Structure-activity relationships were rationalised with molecular docking and molecular dynamics simulations, which also provide insights for future lead compound optimisation. Key words: Alzheimer's disease, tryptophan, IDO-1, amyloid-[beta], neuroinflammation, neuroimmunology La conception de puissants inhibiteurs de l'indoleamine 2,3 dioxygenase 1 (IDOl) ciblant la neuro-inflammation immunopathique constitue desormais un nouveau champ d'interet pour le traitement de la maladie d'Alzheimer (alzheimer). En outre, des donnees recentes sur les bienfaits cliniques des anticorps empechant l'agregation de la beta-amyloide (Aft) ont ravive les efforts visant a decouvrir de petites molecules antiagregantes qui ciblent le mauvais repliement proteopathique des proteines. En exploitant une structure endogene de type tryptophane, nous avons concu et synthetise des inhibiteurs a petite molecule qui ciblent a la fois les processus immunopathiques et proteopathiques, ouvrant ainsi la voie a des monotherapies agissant simultanement sur plusieurs processus pathogenes de l'alzheimer. En particulier, nous presentons des experiences portant sur des composes qui inhibent a la fois IDOl (dans des essais avec des enzymes recombinantes humaines, des cellules HEK293 transferees et des microglies humaines stimulees par 1'interferon [gamma]) et l'agregation de l'A[beta] (dans des essais de liaison avec la thioflavine-T et d'inhibition de l'oligomerisation de l'A[beta] biotinylee). Nous avons identifie cinq composes presentant une forte affinite pour les deux cibles, ce qui nous a permis de definir les (E) 3 styrylindoles comme des composes pouvant servir d'outils pour le developpement d'agents therapeutiques contre l'alzheimer. La penetration cerebrale de ces composes par diffusion passive ou transport actif a ete estimee a l'aide de calculs de l'indice penetration de la barriere hematoencephalique (<< Score BBB >>) et de l'indice d'efficacite de l'exposition cerebrale (<< Score BEE >>), respectivement. Les effets des transporteurs d'efflux (P gp, BCRP) et d'influx (OCT1, OCT2) ont ete egalement ete estimes par calculs. Nous avons rationalise les relations structure-activite a l'aide de simulations d'amarrage moleculaire et de dynamique moleculaire, qui fournissent egalement des informations pour roptimisation d'eventuels composes tetes de serie. [Traduit par la Redaction] Mots-cles : maladie d'Alzheimer, tryptophane, IDOl, beta-amyloide, neuro-inflammation, neuro-immunologie, Introduction The neuropathology of Alzheimer's disease (AD) involves the brain's innate and adaptive immune systems, resulting in a complex inflammatory state that involves not only aggregation of [beta]-amyloid (Aft) and [...]

Background We evaluated the differential impact of levofloxacin administered for the prophylaxis of bloodstream infections compared with broad-spectrum beta-lactam (BSBL) antibiotics used for the treatment of neutropenic fever on the gut microbiome in patients with hematologic malignancy. Methods Stool specimens were collected from patients admitted for chemotherapy or stem cell transplant in the setting of the evaluation of diarrhea from February 2017 until November 2017. Microbiome characteristics were compared among those exposed to levofloxacin prophylaxis vs those who received BSBL antibiotics. Results Sixty patients were included, most with acute myeloid leukemia (42%) or multiple myeloma (37%). The gut microbiome of patients with BSBL exposure had significantly reduced Shannon's alpha diversity compared with those without (median [interquartile range {IQR}], 3.28 [1.73 to 3.71] vs 3.73 [3.14 to 4.31]; P =.01). However, those with levofloxacin exposure had increased alpha diversity compared with those without (median [IQR], 3.83 [3.32 to 4.36] vs 3.32 [2.35 to 4.02]; P =.03). Levofloxacin exposure was also associated with a trend toward lower risk of dominance of non-Bacteroidetes genera compared with those without levofloxacin exposure (3 [14%] vs 15 [38%]; P =.051). Conclusions The impact of antibiotics on the gut microbiome varies by class, and levofloxacin may disrupt the gut microbiome less than BSBLs in this patient population. [ABSTRACT FROM AUTHOR]

Mutations in the genome of SARS-CoV-2 can affect the performance of molecular diagnostic assays. In some cases, such as S-gene target failure, the impact can serve as a unique indicator of a particular SARS-CoV-2 variant and provide a method for rapid detection. Here, we describe partial ORF1ab gene target failure (pOGTF) on the cobas SARS-CoV-2 assays, defined by a ≥2-thermocycle delay in detection of the ORF1ab gene compared to that of the E-gene. We demonstrate that pOGTF is 98.6% sensitive and 99.9% specific for SARS-CoV-2 lineage BA.2.12.1, an emerging variant in the United States with spike L452Q and S704L mutations that may affect transmission, infectivity, and/or immune evasion. Increasing rates of pOGTF closely mirrored rates of BA.2.12.1 sequences uploaded to public databases, and, importantly, increasing local rates of pOGTF also mirrored increasing overall test positivity. Use of pOGTF as a proxy for BA.2.12.1 provides faster tracking of the variant than whole-genome sequencing and can benefit laboratories without sequencing capabilities.

The severe acute respiratory coronavirus-2 (SARS-CoV-2) is the cause of the global outbreak of COVID-19. Evidence suggests that the virus is evolving to allow efficient spread through the human population, including vaccinated individuals. Here, we report a study of viral variants from surveillance of the Delaware Valley, including the city of Philadelphia, and variants infecting vaccinated subjects. We sequenced and analyzed complete viral genomes from 2621 surveillance samples from March 2020 to September 2021 and compared them to genome sequences from 159 vaccine breakthroughs. In the early spring of 2020, all detected variants were of the B.1 and closely related lineages. A mixture of lineages followed, notably including B.1.243 followed by B.1.1.7 (alpha), with other lineages present at lower levels. Later isolations were dominated by B.1.617.2 (delta) and other delta lineages; delta was the exclusive variant present by the last time sampled. To investigate whether any variants appeared preferentially in vaccine breakthroughs, we devised a model based on Bayesian autoregressive moving average logistic multinomial regression to allow rigorous comparison. This revealed that B.1.617.2 (delta) showed 3-fold enrichment in vaccine breakthrough cases (odds ratio of 3; 95% credible interval 0.89-11). Viral point substitutions could also be associated with vaccine breakthroughs, notably the N501Y substitution found in the alpha, beta and gamma variants (odds ratio 2.04; 95% credible interval of1.25-3.18). This study thus overviews viral evolution and vaccine breakthroughs in the Delaware Valley and introduces a rigorous statistical approach to interrogating enrichment of breakthrough variants against a changing background. IMPORTANCE SARS-CoV-2 vaccination is highly effective at reducing viral infection, hospitalization and death. However, vaccine breakthrough infections have been widely observed, raising the question of whether particular viral variants or viral mutations are associated with breakthrough. Here, we report analysis of 2621 surveillance isolates from people diagnosed with COVID-19 in the Delaware Valley in southeastern Pennsylvania, allowing rigorous comparison to 159 vaccine breakthrough case specimens. Our best estimate is a 3-fold enrichment for some lineages of delta among breakthroughs, and enrichment of a notable spike substitution, N501Y. We introduce statistical methods that should be widely useful for evaluating vaccine breakthroughs and other viral phenotypes.