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Federico, D.

Publications and source records attributed to Federico, D..

4 recordsLinked to original sources

Next Generation TB Drug Combinations from the Pan-TB Consortium: Combination Efficacy and Contributions of Individual Agents, Evaluated in a BALB/c Mouse TB Model

The Project to Accelerate New Treatments for Tuberculosis (PAN-TB) aims to accelerate development of shorter, simpler and safer pan-TB combinations. We previously identified 3 out of 25 first-generation novel PAN-TB 4-drug combinations, that cured 90% of mice in less than 3 months, at clinically relevant doses in the relapsing mouse model of TB. These regimens include BPa830Sut, BPa286Sut and BQSut286 (B: bedaquiline; Pa: pretomanid; 830: GSK3211830; 286: GSK2556286; Sut: sutezolid; Q: quabodepistat). Here, we assess the efficacy of these combinations where the original candidates are substituted next-generation or more advanced compounds (ganfeborole (656) for 830, sorfequiline, S for B, TBD09 for Sut and TBD11 for 286) and the individual contributions of specific agents. Six novel regimens demonstrated bactericidal activity more rapid than comparators PHMZ (Rifapentine P, Isoniazid H, Moxifloxacin M, Pyrazinamide Z) and BPaMZ. Modelled cure/relapse data showed that SPa286Sut, SPaSut and SPa656Sut cured 90% of mice in about 1 month, while SPa286, SPaQTBD11 and SPaTBD09 in less than 2 months, faster than PHMZ. Consistent with our previous findings, the fastest-curing regimens centered on a diarylquinoline (S), a nitroimidazole (Pa) and an oxazolidinone (TBD09 or Sut) together with an Rv1625c agonist (TBD11 or 286), DprE1 inhibitor (Q) or a LeuRS inhibitor (656). Notably, significant contributions to sterilizing efficacy were demonstrated for S in all combinations and for Pa, Sut, TBD09, Q and TBD11 or 286 in specific S-containing combinations. These findings suggest potential for these novel agents and combinations to improve treatment of both DS-and DR-TB.

pharmacology and toxicology↗

Gene-Culture Coevolution Favours the Emergence of Traditions in Mate Choice through Conformist Social Learning

The emergence of cultural traditions has long been considered to depend on sophisticated social learning mechanisms, particularly conformist transmission exhibiting a disproportionate bias towards majority behaviours. We challenge this assumption by demonstrating that gene-culture coevolutionary dynamics can fundamentally alter the conditions required for tradition formation, especially in the context of mate choice. Using simulation models of mate choice where female preferences are socially transmitted and male traits are genetically inherited, we show that the interaction between cultural and genetic transmission creates novel evolutionary dynamics. In a first model (the Cultural Model) representing classical cultural evolution scenarios, we show that traditions emerge only when conformity disproportionately amplifies majority behaviours. In a second model (the Gene-Culture Model), we introduce a distinction between learned behaviours and realized behaviours and show that when mate choice depends on both conformist learning and male trait availability, even simple social learning strategies can establish persistent traditions. In this context, majority exaggeration is no longer a necessary property of social learning for traditions to arise. This occurs because positive frequency-dependent interactions between preference and trait dynamics provide an additional mechanism that reinforces majority behaviours beyond conformist learning. Our findings have broader implications for cultural evolution theory, suggesting that many behaviours that depend on resource availability may exhibit tradition-like patterns under less stringent social learning conditions than previously assumed. By distinguishing between preference and choice, and demonstrating the importance of gene-culture interactions, this study advocates for more integrated approaches to understanding cultural evolution that consider the interplay between multiple inheritance systems.

evolutionary biology↗

A modeling-based framework to evaluate forgiveness of TB drug combinations in a BALB/c relapsing mouse model.

Tuberculosis (TB) remains a leading cause of death due to an infectious agent. Adherence to long and complex TB treatments is supported by methods including directly observed therapy. The negative impact of missed drug doses on clinical outcomes is well-established, highlighting both the importance of adherence support and methods to quantify the ability of a regimen to continue exerting a biologic effect, during gaps in dosing known as "forgiveness" property. To explore the value of the BALB/c Relapsing Mouse Model of TB in evaluating treatment forgiveness, we assessed the impact of weekend dose holidays on the bactericidal, including RS ratio(R), and sterilizing efficacy of RHZE/RH and BPaMZ in perspective of each drug exposure. The cure/relapse data from this study plus multiple historical studies were used to identify a nonlinear mixed-effects Emax model that was used to estimate time to cure 50% and derive time to cure 90% mice (T90). Expected time-dependent bactericidal activity and reductions in RS ratio were observed for both treatments, with more rapid decreases for the BPaMZ groups. The weekend dosing holiday significantly decreased reductions in lung CFU and RS ratio earlier in RHZE/RH treatment, but no such effect was observed for BPaMZ. Similarly, the predicted T90 was significantly greater for RHZE/RH (but not BPaMZ), with weekend doses omitted. No major drug exposure difference was observed between the 2 dosing schedules. Our results suggest BPaMZ is more forgiving of missed doses than RHZE/RH and suggests utility of this methodology to support evaluation of TB treatment forgiveness.

pharmacology and toxicology↗

Chromatin structure changes in Daphnia populations upon exposure to environmental cues - or - The discovery of Wolterecks \"Matrix\"

Phenotypic plasticity is an important feature of biological systems that is likely to play a major role in the future adaptation of organisms to the ongoing global changes. It may allow an organism to produce alternative phenotypes in responses to environmental cues. Modifications in the phenotype can be reversible but are sometimes enduring and can even span over generations. The notion of phenotypic plasticity was conceptualized in the early 20th century by Richard Woltereck. He introduced the idea that the combined relations of a phenotypic character and all environmental gradients that influence on it can be defined as \"norm of reaction\". Norms of reaction are specific to species and to lineages within species, and they are heritable. He postulated that reaction norms can progressively be shifted over generations depending on the environmental conditions. One of his biological models was the water-flee daphnia. Woltereck proposed that enduring phenotypic modifications and gene mutations could have similar adaptive effects, and he postulated that their molecular bases would be different. Mutations occurred in genes, while enduring modifications were based on something he called the Matrix. He suggested that this matrix (i) was associated with the chromosomes, (ii) that it was heritable, (iii) it changed during development of the organisms, and (iv) that changes of the matrix could be simple chemical substitutions of an unknown, but probably polymeric molecule. We reasoned that the chromatin has all postulated features of this matrix and revisited Wolterecks classical experiments with daphnia. We developed a robust and rapid ATAC-seq technique that allows for analyzing chromatin of individual daphnia and show here (i) that this technique can be used with minimal expertise in molecular biology, and (ii) we used it to identify open chromatin structure in daphnia exposed to different environmental cues. Our result indicates that chromatin structure changes consistently in daphnia upon this exposure confirming Wolterecks classical postulate.

evolutionary biology↗