Anthelmintic screening of five palmatilobae species used in Traditional Medicine in Katanga Province (DR Congo)

Aim of the study: resistance to known anthelmintics has become a growing concern. Based on 2017-2019 ethnomedical and ethnoveterinary surveys carried out in Katanga Province, several species of shrub locally identified as Vitex species (Lamiaceae) are used to treat helminthiases. In this study, 5 of these species, including different morphotypes, were selected for in vitro screening in order to search for new anthelmintic lead compounds. Method: n-heptane, dichloromethane (DCM), ethyl acetate (EtOAc) and methanol (MeOH) extracts of selected plants (leaves, root barks and stem barks) were evaluated for their anthelmintic activity. The experiment was assessed using a standard motility assay on the N2 wild-type Caenorhabditis elegans strain. Results: anthelmintic activity was confirmed by the calculation of motility inhibition. The following extracts, tested at 200 μg extract/mL, were significantly active on this model (average ± SD; n = 3; positive control, levamisole, 50 μM : 98.7 ± 4.3% of motility inhibition) : Oldfieldia dactylophylla (Welw. ex Oliv.) (Picrodendraceae; locally misidentified as V. congolensis De Wild and T. Durand) [DCM leaves (71.0 ± 5.7%), MeOH stem barks (90.0 ± 7.3%) and MeOH stem roots (97.0 ± 5.9%)] ; V. doniana Sweet [EtOAc leaves (64.0 ± 4.4%)] ; V. fischeri Gürke [n-heptane leaves (98.0 ± 7.8%)] ; V. madiensis subsp. Milanjiensis (Britten) F. White [DCM leaves 3-5 leaflets (65.0 ± 5.6%) and 5 leaflets (69.0 ± 6.6%)] and V. mombassae Vatke [DCM leaves 3-5 leaflets (62.0 ± 8.1%)]. Conclusion: the motility inhibitions measured on the N2 wild-type Caenorhabditis elegans model provide support for the traditional use of these plants and call for further studies to develop compounds as possible treatments for parasitic worm infections. The misidentification of Oldfieldia dactylophylla seems to be general in the study region.Phytokat : Conditions pour l'intégration de la médecine traditionnelle aux soins de santé modernes: caractérisation, validation biologique et culture ex situ de plantes médicinale

Homelessness in Europe and the United States: A comparison of prevalence and public opinion

Random samples of 250-435 adults were interviewed by telephone in five different nations (N = 1,546): Belgium, Germany, Italy, the UK, and the United States. The interview included questions on respondent attitudes, knowledge, and opinions regarding homelessness; respondents' own personal experiences with homelessness and homeless people; and demographic characteristics of the respondents. The highest rates for lifetime literal homelessness were found in the UK (7.7%) and United States (6.2%), with the lowest rate in Germany (2.4%), and intermediate rates in Italy (4.0%) and Belgium (3.4%). Less compassionate attitudes toward the homeless were also found on many dimensions in the United States and the UK. Possible explanations of these findings, drawn from various theoretical perspectives, and policy implications are provided

Synthesis of Polyurethanes Using Organocatalysis: A Perspective

Organocatalysis has become an invaluable tool for polymer synthesis, and its utility has been demonstrated in ring-opening, anionic, zwitterionic, and group-transfer polymerizations. Despite this, the use of organocatalysis in other polymerization reactions such as step-growth polymerizations remains underexplored, relative to more traditional metal-based polymerizations. Recently, the use of organic bases such as guanidines, amidines, N-heterocyclic carbenes, and organic "strong or super-strong" Bronsted acids to catalyze the synthesis of metal-free polyurethanes has shown to be competitive to commercially widely used dibutyltin dilaurate and dibutyltin diacetate catalysts. This Perspective article highlights recent advances in organocatalyst design for isocyanate-based polyurethane synthesis with the aim of comparing the activity and selectivity of each of the new catalytic reactions to each other and the traditional metal-based catalysts. The article also draws attention to new trends in isocyanate-free polyurethane synthesis and the key role that organocatalysis is playing in these innovative polymerization processes