The pseudo‐natural product rhonin targets RHOGDI

For the discovery of novel chemical matter generally endowed with bioactivity, strategies may be particularly efficient that combine previous insight about biological relevance, e.g., natural product (NP) structure, with methods that enable efficient coverage of chemical space, such as fragment-based design. We describe the de novo combination of different 5-membered NP-derived N-heteroatom fragments to structurally unprecedented “pseudo-natural products” in an efficient complexity-generating and enantioselective one-pot synthesis sequence. The pseudo-NPs inherit characteristic elements of NP structure but occupy areas of chemical space not covered by NP-derived chemotypes, and may have novel biological targets. Investigation of the pseudo-NPs in unbiased phenotypic assays and target identification led to the discovery of the first small-molecule ligand of the RHO GDP-dissociation inhibitor 1 (RHOGDI1), termed Rhonin. Rhonin inhibits the binding of the RHOGDI1 chaperone to GDP-bound RHO GTPases and alters the subcellular localization of RHO GTPases

The pseudo‐natural product rhonin targets RHOGDI

For the discovery of novel chemical matter generally endowed with bioactivity, strategies may be particularly efficient that combine previous insight about biological relevance, e.g., natural product (NP) structure, with methods that enable efficient coverage of chemical space, such as fragment-based design. We describe the de novo combination of different 5-membered NP-derived N-heteroatom fragments to structurally unprecedented “pseudo-natural products” in an efficient complexity-generating and enantioselective one-pot synthesis sequence. The pseudo-NPs inherit characteristic elements of NP structure but occupy areas of chemical space not covered by NP-derived chemotypes, and may have novel biological targets. Investigation of the pseudo-NPs in unbiased phenotypic assays and target identification led to the discovery of the first small-molecule ligand of the RHO GDP-dissociation inhibitor 1 (RHOGDI1), termed Rhonin. Rhonin inhibits the binding of the RHOGDI1 chaperone to GDP-bound RHO GTPases and alters the subcellular localization of RHO GTPases

Thresholds of Toxicological Concern for Cosmetics-Related Substances: New Database, Thresholds, and Enrichment of Chemical Space

A new dataset of cosmetics-related chemicals for the Threshold of Toxicological Concern (TTC) approach has been compiled, comprising 552 chemicals with 219, 40, and 293 chemicals in Cramer Classes I, II, and III, respectively. Data were integrated and curated to create a database of No-/Lowest-Observed-Adverse-Effect Level (NOAEL/LOAEL) values, from which the final COSMOS TTC dataset was developed. Criteria for study inclusion and NOAEL decisions were defined, and rigorous quality control was performed for study details and assignment of Cramer classes. From the final COSMOS TTC dataset, human exposure thresholds of 42 and 7.9 μg/kg-bw/day were derived for Cramer Classes I and III, respectively. The size of Cramer Class II was insufficient for derivation of a TTC value. The COSMOS TTC dataset was then federated with the dataset of Munro and colleagues, previously published in 1996, after updating the latter using the quality control processes for this project. This federated dataset expands the chemical space and provides more robust thresholds. The 966 substances in the federated database comprise 245, 49 and 672 chemicals in Cramer Classes I, II and III, respectively. The corresponding TTC values of 46, 6.2 and 2.3 μg/kg-bw/day are broadly similar to those of the original Munro dataset

BCG scarring and improved child survival : a combined analysis of studies of BCG scarring

Bacillus Calmette–Guérin (BCG) vaccine against tuberculosis (TB) is recommended given at birth in TB-endemic areas. Currently, BCG vaccination programmes use “BCG vaccination coverage by 12 months of age” as the performance indicator. Previous studies suggest that BCG-vaccinated children, who develop a scar, have better overall survival compared with BCG-vaccinated children, who do not develop a scar. We summarized the available studies of BCG scarring and child survival. A structured literature search for studies with original data and analysis of BCG scarring and mortality. Combined analyses on effect of BCG scarring on overall mortality. We identified six studies covering seven cohorts, all from Guinea-Bissau, West Africa, with evaluation of BCG scarring amongst BCG-vaccinated children and follow-up for mortality. Determinants for BCG scarring were BCG strain, intradermal injection route, size of injection wheal, and co-administered vaccines and micronutrients. In a combined analysis, having a BCG scar vs. no BCG scar was associated with a mortality rate ratio (MRR) of 0.61 (95% CI: 0.51–0.74). The proportion with a BCG scar varied from 52 to 93%; the estimated effect of a BCG scar was not associated with the scar prevalence. The effect was strongest in the first (MRR = 0.48 (0.37–0.62)) and second (MRR = 0.63 (0.44–0.92)) year of life, and in children BCG-vaccinated in the neonatal period (MRR = 0.45 (0.36–0.55). The effect was not explained by protection against TB. Confounding and genetic factors are unlikely to explain the strong association between BCG scarring and subsequent survival. Including “BCG scar prevalence” as a BCG vaccination programme performance indicator should be considered. The effect of revaccinating scar-negative children should be studied

Néoglycoprotéines à sonde paramagnétique

1-Deoxy-1(N-hydroxyamino)-D-glucitol has been fixed onto human and bovine serumalbumin through a pentamethylene spacer arm. The modified proteins were purified by dialysis, electrophoresis and high pressure liquid chromatography to insure, in particular, a complete removal of low molecular weight starting materials. The fixation of the sugar derivative onto the protein was established by an increase in sugar content and the obtention of usable e.s.r. spectra from the nitroxide free radicals, obtained from the spontaneous oxidation of the N-hydroxyamino group. E.s. r. hyperfine coupling constants gave information on the conformation of the magnetic probe

Effects of the nitric oxide donor, DEA/NO on cortical spreading depression.

NoCortical spreading depression (CSD) is a transient disruption of local ionic homeostasis that may promote migraine attacks and the progression of stroke lesions. We reported previously that the local inhibition of nitric oxide (NO) synthesis with N¿-nitro-L-arginine methyl ester (L-NAME) delayed markedly the initiation of the recovery of ionic homeostasis from CSD. Here we describe a novel method for selective, controlled generation of exogenous NO in a functioning brain region. It is based on microdialysis perfusion of the NO donor, 2-(N,N-diethylamino)-diazenolate-2-oxide (DEA/NO). As DEA/NO does not generate NO at alkaline pH, and as the brain has a strong acid-base buffering capacity, DEA/NO was perfused in a medium adjusted at alkaline (but unbuffered) pH. Without DEA/NO, such a microdialysis perfusion medium did not alter CSD. DEA/NO (1, 10 and 100 ¿M) had little effect on CSD by itself, but it reversed in a concentration-dependent manner the effects of NOS inhibition by 1 mM L-NAME. These data demonstrate that increased formation of endogenous NO associated with CSD is critical for subsequent, rapid recovery of cellular ionic homeostasis. In this case, the molecular targets for NO may be located either on brain cells to suppress mechanisms directly involved in CSD genesis, or on local blood vessels to couple flow to the increased energy demand associated with CS

Using BCG vaccine to enhance non-specific protection of health care workers during the COVID-19 pandemic: A structured summary of a study protocol for a randomised controlled trial in Denmark

OBJECTIVES: The Bacille Calmette-Guérin (BCG) vaccine against tuberculosis is associated with non- specific protective effects against other infections, and significant reductions in all-cause morbidity and mortality have been reported. We aim to test whether BCG vaccination may reduce susceptibility to and/or the severity of COVID-19 and other infectious diseases in health care workers (HCW) and thus prevent work absenteeism.The primary objective is to reduce absenteeism due to illness among HCW during the COVID-19 pandemic. The secondary objectives are to reduce the number of HCW that are infected with SARS-CoV-2, and to reduce the number of hospital admissions among HCW during the COVID-19 pandemic. HYPOTHESIS: BCG vaccination of HCW will reduce absenteeism by 20% over a period of 6 months. TRIAL DESIGN: Placebo-controlled, single-blinded, randomised controlled trial, recruiting study participants at several geographic locations. The BCG vaccine is used in this study on a different indication than the one it has been approved for by the Danish Medicines Agency, therefore this is classified as a phase III study. PARTICIPANTS: The trial will recruit 1,500 HCW at Danish hospitals.To be eligible for participation, a subject must meet the following criteria: Adult (≥18 years); Hospital personnel working at a participating hospital for more than 22 hours per week.A potential subject who meets any of the following criteria will be excluded from participation in this study: Known allergy to components of the BCG vaccine or serious adverse events to prior BCG administration Known prior active or latent infection with Mycobacterium tuberculosis (M. tuberculosis) or other mycobacterial species Previous confirmed COVID-19 Fever (>38 C) within the past 24 hours Suspicion of active viral or bacterial infection Pregnancy Breastfeeding Vaccination with other live attenuated vaccine within the last 4 weeks Severely immunocompromised subjects. This exclusion category comprises: a) subjects with known infection by the human immunodeficiency virus (HIV-1) b) subjects with solid organ transplantation c) subjects with bone marrow transplantation d) subjects under chemotherapy e) subjects with primary immunodeficiency f) subjects under treatment with any anti-cytokine therapy within the last year g) subjects under treatment with oral or intravenous steroids defined as daily doses of 10 mg prednisone or equivalent for longer than 3 months h) Active solid or non-solid malignancy or lymphoma within the prior two years Direct involvement in the design or the execution of the BCG-DENMARK-COVID trial Intervention and comparator: Participants will be randomised to BCG vaccine (BCG-Denmark, AJ Vaccines, Copenhagen, Denmark) or placebo (saline). An adult dose of 0.1 ml of resuspended BCG vaccine (intervention) or 0.1 ml of sterile 0.9% NaCl solution (control) is administered intradermally in the upper deltoid area of the right arm. All participants will receive one injection at inclusion, and no further treatment of study participants will take place. MAIN OUTCOMES: Main study endpoint: Days of unplanned absenteeism due to illness within 180 days of randomisation.Secondary study endpoints: The cumulative incidence of documented COVID-19 and the cumulative incidence of hospital admission for any reason within 180 days of randomisation.Randomisation: Randomisation will be done centrally using the REDCap tool with stratification by hospital, sex and age groups (+/- 45 years of age) in random blocks of 4 and 6. The allocation ratio is 1:1.Blinding (masking): Participants will be blinded to treatment. The participant will be asked to leave the room while the allocated treatment is prepared. Once ready for injection, vaccine and placebo will look similar, and the participant will not be able to tell the difference.The physicians administering the treatment are not blinded.Numbers to be randomised (sample size): Sample size: N=1,500. The 1,500 participants will be randomised 1:1 to BCG or placebo with 750 participants in each group.Trial Status: Current protocol version 5.1, from July 6, 2020.Recruitment of study participants started on May 18, 2020 and we anticipate having finished recruiting by the end of December 2020. TRIAL REGISTRATION: The trial was registered with EudraCT on April 16, 2020, EudraCT number: 2020-001888-90, and with ClinicalTrials.gov on May 1, 2020, registration number NCT04373291.Full protocol: The full protocol is attached as an additional file, accessible from the Trialswebsite (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol

BCG vaccination-induced emergency granulopoiesis provides rapid protection from neonatal sepsis

Death from sepsis in the neonatal period remains a serious threat for millions. Within 3 days of administration, bacille Calmette-Guérin (BCG) vaccination can reduce mortality from neonatal sepsis in human newborns, but the underlying mechanism for this rapid protection is unknown. We found that BCG was also protective in a mouse model of neonatal polymicrobial sepsis, where it induced granulocyte colony-stimulating factor (G-CSF) within hours of administration. This was necessary and sufficient to drive emergency granulopoiesis (EG), resulting in a marked increase in neutrophils. This increase in neutrophils was directly and quantitatively responsible for protection from sepsis. Rapid induction of EG after BCG administration also occurred in three independent cohorts of human neonates

A novel disorder involving dyshematopoiesis, inflammation, and HLH due to aberrant CDC42 function

Hemophagocytic lymphohistiocytosis (HLH) is characterized by immune dysregulation due to inadequate restraint of overactivated immune cells and is associated with a variable clinical spectrum having overlap with more common pathophysiologies. HLH is difficult to diagnose and can be part of inflammatory syndromes. Here, we identify a novel hematological/autoinflammatory condition (NOCARH syndrome) in four unrelated patients with superimposable features, including neonatal-onset cytopenia with dyshematopoiesis, autoinflammation, rash, and HLH. Patients shared the same de novo CDC42 mutation (Chr1:22417990C>T, p.R186C) and altered hematopoietic compartment, immune dysregulation, and inflammation. CDC42 mutations had been associated with syndromic neurodevelopmental disorders. In vitro and in vivo assays documented unique effects of p.R186C on CDC42 localization and function, correlating with the distinctiveness of the trait. Emapalumab was critical to the survival of one patient, who underwent successful bone marrow transplantation. Early recognition of the disorder and establishment of treatment followed by bone marrow transplant are important to survival