Discovery of CDC42 Inhibitors with a Favorable Pharmacokinetic Profile and Anticancer In Vivo Efficacy.

We previously reported trisubstituted pyrimidine lead compounds, namely, ARN22089 and ARN25062, which block the interaction between CDC42 with its specific downstream effector, a PAK protein. This interaction is crucial for the progression of multiple tumor types. Such inhibitors showed anticancer efficacy in vivo. Here, we describe a second class of CDC42 inhibitors with favorable drug-like properties. Out of the 25 compounds here reported, compound 15 (ARN25499) stands out as the best lead compound with an improved pharmacokinetic profile, increased bioavailability, and efficacy in an in vivo PDX tumor mouse model. Our results indicate that these CDC42 inhibitors represent a promising chemical class toward the discovery of anticancer drugs, with ARN25499 as an additional lead candidate for preclinical development.

Tezacaftor is a direct inhibitor of sphingolipid delta-4 desaturase enzyme (DEGS).

BACKGROUND: We recently demonstrated that 48 h exposure of primary human bronchial epithelial (hBE) cells, obtained from both CF (F508del homozygous) and non-CF subjects, to the triple drug combination Elexacaftor/Tezacaftor/Ivacaftor (ETI) results in a CFTR genotype-independent modulation of the de novo synthethic pathway of sphingolipids, with an accumulation of dihydroceramides (dHCer). Since dHCer are converted into ceramides (Cer) by the action of a delta-4 sphingolipid desaturase (DEGS) enzyme, we aimed to better understand this off-target effect of ETI (i.e., not related to CFTR rescue) METHODS: hBE cells, both F508del and wild-type, were cultured to create fully differentiated bronchial epithelia. We analyzed Cer and dHCer using an LC-MS based method previously developed by our lab. DEGS expression levels in differentiated hBE cells lysates were quantified by western blot analysis. RESULTS: We demonstrated that 1) dHCer accumulate in hBE with time following prolonged ETI exposure, that 2) similar inhibition occurs in wild-type primary human hepatocytes and that 3) this does not result in an alteration of DEGS expression. We then proved that 4) ETI is a direct inhibitor of DEGS, that 5) Tezacaftor is the molecule responsible for this effect, that 6) the inhibition is concentration dependent. Finally, after repeated oral administration of ETI to naïve, non-CF, mice, we observed a slight accumulation of dHCer in the brain. CONCLUSIONS: We believe that further investigations on Tezacaftor should be envisaged, particularly for the use of ETI during pregnancy, breastfeeding and in the early stages of development. DEGS dysfunction and dHCer accumulation causes impairment in the development of the nervous system, due to a derangement in myelin formation and maintenance.

Schiff Base-Based Hydrogel Embedded with In Situ Generated Silver Nanoparticles Capped by a Hyaluronic Acid-Diethylenetriamine Derivative for Wound Healing Application.

In this study, hydrogels were produced using a Schiff base reaction between two hyaluronic acid derivatives: one containing aldehyde groups (HA-Ald) and the other holding a diethylenetriamine with terminal amino groups (HA-DETA). The DETA portion promotes the in situ growth, complexation, and stabilization of silver nanoparticles (AgNPs), eliminating the need for external reducing agents. The reaction between HA-DETA and HA-Ald leads to the formation of imine bonds, which results in dynamically pH-responsive cross-linking. While the DETA capping ability helped in embedding the AgNPs, the on/off pH environmental responsivity of the hydrogel allows for a controlled and on-demand release of the drug, mainly when bacterial infections cause pH variation of the wound bed. The injectable hydrogels resulted in being highly compatible in contact with blood red cells, fibroblasts, and keratinocytes and capable of having a proliferative effect on an in vitro wound scratch model. The pH-responsive hydrogels showed proper antibacterial activity againstPseudomonas aeruginosaandStaphylococcus aureus, common bacterial strains presented in wound infections. Finally, in vivo wound model studies demonstrated an overall speeding up in the wound healing rate and advanced wound conditions in the experimental group treated with the hydrogels compared to control samples.

PFAS-free superhydrophobic chitosan coating for fabrics.

In view of health and environmental concerns, together with the upcoming restrictive regulations on per- and polyfluoroalkyl substances (PFAS), less impactful materials must be explored for the hydrophobization of surfaces. Polysaccharides, and especially chitosan, are being explored for their desirable properties of film formation and ease of modification. We present a PFAS-free chitosan superhydrophobic coating for textiles deposited through a solvent-free method. By contact angle analysis and drop impact, we observe that the coating imparts hydrophobicity to the fabrics, reaching superhydrophobicty (θA = 151°, θR = 136°) with increased amount of coating (from 1.6 g/cm2). This effect is obtained by the combination of chemical water repellency of the modified chitosan and the nano- and micro-roughness, assessed by SEM analysis. We perform a comprehensive study on the durability of the coatings, showing good results especially for acidic soaking where the hydrophobicity is maintained until the 8th cycle of washing. We assess the degradation of the coating by a TGA-IR investigation to define the compounds released with thermal degradation, and we confirm the coating's biodegradability by biochemical oxygen consumption. Finally, we demonstrate its biocompatibility on keratinocytes (HaCaT cell line) and fibroblasts (HFF-1 cell line), confirming that the coating is safe for human skin cells.

Vision-based omnidirectional indoor robots for autonomous navigation and localization in manufacturing industry.

In this paper, we present a new generation of omnidirectional automated guided vehicles (omniagv) used for transporting materials within a manufacturing factory with the ability to navigate autonomously and intelligently by interacting with the environment, including people and other entities. This robot has to be integrated into the operating environment without significant changes to the current facilities or heavy redefinitions of the logistics processes already running. For this purpose, different vision-based systems and advanced methods in mobile and cognitive robotics are developed and integrated. In this context, vision and perception are key factors. Different developed modules are in charge of supporting the robot during its navigation in the environment. Specifically, the localization module provides information about the robot pose by using visual odometry and wheel odometry systems. The obstacle avoidance module can detect obstacles and recognize some object classes for adaptive navigation. Finally, the tag detection module aids the robot during the picking phase of carts and provides information for global localization. The smart integration of vision and perception is paramount for effectively using the robot in the industrial context. Extensive qualitative and quantitative results prove the capability and effectiveness of the proposed AGV to navigate in the considered industrial environment.

Natural Plasmodium infections in Brazilian wild monkeys: Reservoirs for human infections?

Four hundred and forty-eight samples of total blood from wild monkeys living in areas where human autochthonous malaria cases have been reported were screened for the presence of Plasmodium using microscopy and PCR analysis. Samples came from the following distinct ecological areas of Brazil: Atlantic forest (N = 140), semideciduous Atlantic forest (N = 257) and Cerrado (a savannah-like habitat) (N = 51). Thick and thin blood smears of each specimen were examined and Plasmodium infection was screened by multiplex polymerase chain reaction (multiplex PCR). The frequency of Plasmodium infections detected by PCR in Alouatta guariba clamitans in the São Paulo Atlantic forest was 11.3% or 8/71 (5.6% for Plasmodium malariae and 5.6% for Plasmodium vivax) and one specimen was positive for Plasmodium falciparum (1.4%); Callithrix sp. (N = 30) and Cebus apella (N = 39) specimens were negative by PCR tests. Microscopy analysis was negative for all specimens from the Atlantic forest. The positivity rate for Alouatta caraya from semideciduous Atlantic forest was 6.8% (16/235) in the PCR tests (5.5, 0.8 and 0.4% for P. malariae, P. falciparum and P. vivax, respectively), while C. apella specimens were negative. Parasitological examination of the samples using thick smears revealed Plasmodium sp. infections in only seven specimens, which had few parasites (3.0%). Monkeys from the Cerrado (a savannah-like habitat) (42 specimens of A. caraya, 5 of Callithrix jacchus and 4 of C. apella) were negative in both tests. The parasitological prevalence of P. vivax and P. malariae in wild monkeys from Atlantic forest and semideciduous Atlantic forest and the finding of a positive result for P. falciparum in Alouatta from both types of forest support the hypothesis that monkeys belonging to this genus could be a potential reservoir. Furthermore, these findings raise the question of the relationship between simian and autochthonous human malaria in extra-Amazonian regions.

Phagocytic activity mediated via FcyR, FcuR, and CR3 and H2O2 release during ontogeny of mouse macrophages

Mouse macrophage phagocytic activity was studied during ontogenetic development by comparing the abilities of infant and adult mouse macrophages to ingest opsonized particles via FcãR, FcìR, or CR3. These studies were performed on resident, BCG-, and thioglycollate-stimulated peritoneal macrophages. The percent of ingestion and the index of maximal phagocytosis mediated via FcãR is lower in infant than in adult mouse macrophages. However, the adherence mediated by FcãR is similar to that seen with adult cells. Similar results were obtained when phagocytosis was mediated via FcìR or CR3, reaching adult levels during ontogenetic development. We also studied the age-dependent release of H2O2 by peritoneal cells before and after incubation with phorbol myristate acetate. Interestingly, the capacity of peritoneal cells from infant animals to generate H2O2 after BCG infection is similar to that observed in adult mice. Our results suggest that the adherence and phagocytosis mediated by FcãR, although at lower levels than in adults, and the production of microbicidal H2O2 may be relevant for mouse survival during the first days of life.

Mycoplasma pulmonis e/ou Mycoplasma arthritidis em animais de laboratório (ratos e camundongos) de diferentes biotérios / Mycoplasma pulmonis and Mycoplasma arthriditis in rodents from animal houses

Ratos e camundongos de três biotérios com e um sem barreiras microbianas foram bacteriologicamente estudados quanto à presença de micoplasma, através da perfusäo de pulmäo com lavado traqueobrônquico e lavado de ouvido. Caracterizou-se a presença destas bactérias pela formaçäo de colônias em "ovo frito", coloraçäo de Dienes, resistência à digitonina, catabolismo da glicose, hidrólise da arginina, reduçäo do tetrazólio e produçäo de filme e manchas. A identificaçäo das cepas isoladas foi através da inibiçäo de crescimento. No biotério com barreiras microbianas, os micoplasmas näo foram detectados. Entretanto, isolou-se Mycoplasma pulmonis e Mycoplasma arthritidis em biotérios sem barreiras. Nas instalaçöes sem barreiras microbianas com amostragem representativa, detectou-se M. pulmonis em 20//dos camundongos Swiss, 14,28//na linhagem C57B1/6J e em 83,78//na amostragem dos ratos. Encontrou-se M. arthritidis em 5,4//dos ratos, através da lavagem de ouvido. Ambas as espécies estavam presentes em 2,7//dos ratos. Os anti-soros utilizados näo identificaram uma cepa isolada de hamster. M. pulmonis foi identificado em ratos de um grupo de animais procedentes de outros 2 biotérios. A taxa de infecçäo por micoplasma näo pôde ser estabelecida porque os ratos e camundongos foram especialmente selecionados para a pesquisa de micoplasma devido a sua origem a aspectos clínicos. Os autores sugerem que a pesquisa de micoplasma em animais de laboratório seja freqüente, com amostragem representativa e com a identificaçäo destes microrganismos para o aprimoramento de seu controle

Desempenho reprodutivo de ratos Wistar mantidos em dois sistemas de criaçäo na colônia convencional do Biotério Central da Faculdade de Medicina USP / Breeding performance of Wistar rats bred in two systems at the conventional Animal House of the Faculdade de Medicina-USP

O sistema monogâmico de acasalamento empregado na criaçäo de ratos Wistar do Biotério Central (DTAEP) da Faculdade de Medicina da USP mostrou-se insuficiente para o fornecimento da quantidade de ratos machos requerida pelos laboratórios de investigaçäo médica. No intuito de aumentar a produçäo e, ao mesmo tempo, aproveitar o excesso de fêmeas produzidas, foi introduzido na colônia o sistema de harém cross-fostered. Neste estudo foi analisada, em um período de 17 meses, a performance reprodutiva dos animais criados em cada um dos sistemas utilizados. Os resultados obtidos mostraram que o sistema monogâmico teve maior produtividade e forneceu os jovens reprodutores para a propagaçäo da colônia. Por outro lado, o harém pode ser dirigido para a produçäo de ratos machos. Concluiu-se que a manutençäo simultânea dos dois sistemas de criaçäo foi adequada para atender tanto às necessidades dos laboratórios quanto à reposiçäo da colônia

Rabies in the State of Säo Paulo: the rodents question

Compulsaram-se dados epidemiológicos a respeito de agressäo por roedores no período de 1976 a 1985, nos registros do Instituto Pasteur de Säo Paulo (Brasil). Observou-se que de 367 379 pessoas agredidas, 22 250 foram vítimas de roedores. Os roedores mais implicados nesses acidentes foram os urbanos, sendo que a captura foi um fator limitante para o envio de amostras ao laboratório. O diagnóstico laboratorial realizado em 1083 amostras de roedores näo revelou nenhum caso positivo no período, embora a raiva estivesse presente em outras espécies animais. Conclui-se que, sendo a raiva rara entre os roedores, é necessário que se realizem provas de identificaçäo do vírus quando houver suspeita de caso positivo; e que, näo existindo casos relatados de óbitos humanos por raiva relacionados a roedores, existe a possibilidade de reduçäo dos tratamentos anti-rábico pós-exposiçäo a estes animais