High-throughput screening of metal-porphyrin-like graphenes for selective capture of carbon dioxide

Nanostructured materials, such as zeolites and metal-organic frameworks, have been considered to capture CO2. However, their application has been limited largely because they exhibit poor selectivity for flue gases and low capture capacity under low pressures. We perform a high-throughput screening for selective CO2 capture from flue gases by using first principles thermodynamics. We find that elements with empty d orbitals selectively attract CO2 from gaseous mixtures under low CO2 pressures (similar to 10(-3) bar) at 300 K and release it at similar to 450 K. CO2 binding to elements involves hybridization of the metal d orbitals with the CO2 pi orbitals and CO2-transition metal complexes were observed in experiments. This result allows us to perform high-throughput screening to discover novel promising CO2 capture materials with empty d orbitals (e.g., Sc- or V-porphyrin-like graphene) and predict their capture performance under various conditions. Moreover, these findings provide physical insights into selective CO2 capture and open a new path to explore CO2 capture materialsopen

Risks to Birds Traded for African Traditional Medicine: A Quantitative Assessment

Few regional or continent-wide assessments of bird use for traditional medicine have been attempted anywhere in the world. Africa has the highest known diversity of bird species used for this purpose. This study assesses the vulnerability of 354 bird species used for traditional medicine in 25 African countries, from 205 genera, 70 families, and 25 orders. The orders most represented were Passeriformes (107 species), Falconiformes (45 species), and Coraciiformes (24 species), and the families Accipitridae (37 species), Ardeidae (15 species), and Bucerotidae (12 species). The Barn owl (Tyto alba) was the most widely sold species (seven countries). The similarity of avifaunal orders traded is high (analogous to ‘‘morphospecies’’, and using Sørensen’s index), which suggests opportunities for a common understanding of cultural factors driving demand. The highest similarity was between bird orders sold in markets of Benin vs. Burkina Faso (90%), but even bird orders sold in two geographically separated countries (Benin vs. South Africa and Nigeria vs. South Africa) were 87% and 81% similar, respectively. Rabinowitz’s ‘‘7 forms of rarity’’ model, used to group species according to commonness or rarity, indicated that 24% of traded bird species are very common, locally abundant in several habitats, and occur over a large geographical area, but 10% are rare, occur in low numbers in specific habitats, and over a small geographical area. The order with the highest proportion of rare species was the Musophagiformes. An analysis of species mass (as a proxy for size) indicated that large and/or conspicuous species tend to be targeted by harvesters for the traditional medicine trade. Furthermore, based on cluster analyses for species groups of similar risk, vultures, hornbills, and other large avifauna, such as bustards, are most threatened by selective harvesting and should be prioritised for conservation action.University of the Witwatersrand SPARC Prestigious and URC Postdoctoral Fellowships; National Research Foundatio

Ruthenium complex containing 1,3-thiazolidine-2-thione inhibits hepatic cancer stem cells by suppressing Akt/mTOR signalling and leading to apoptotic and autophagic cell death

\ua9 2024 The AuthorsHepatic cancer is one of the main causes of cancer-related death worldwide. Cancer stem cells (CSCs) are a unique subset of cancer cells that promote tumour growth, maintenance, and therapeutic resistance, leading to recurrence. In the present work, the ability of a ruthenium complex containing 1,3-thiazolidine-2-thione (RCT), with the chemical formula [Ru(tzdt)(bipy)(dppb)]PF6, to inhibit hepatic CSCs was explored in human hepatocellular carcinoma HepG2 cells. RCT exhibited potent cytotoxicity to solid and haematological cancer cell lines and reduced the clonogenic potential, CD133+ and CD44high cell percentages and tumour spheroid growth of HepG2 cells. RCT also inhibited cell motility, as observed in the wound healing assay and transwell cell migration assay. RCT reduced the levels of Akt1, phospho-Akt (Ser473), phospho-Akt (Thr308), phospho-mTOR (Ser2448), and phospho-S6 (Ser235/Ser236) in HepG2 cells, indicating that interfering with Akt/mTOR signalling is a mechanism of action of RCT. The levels of active caspase-3 and cleaved PARP (Asp214) were increased in RCT-treated HepG2 cells, indicating the induction of apoptotic cell death. In addition, RCT modulated the autophagy markers LC3B and p62/SQSTM1 in HepG2 cells and increased mitophagy in a mt-Keima-transfected mouse embryonic fibroblast (MEF) cell model, and RCT-induced cytotoxicity was partially prevented by autophagy inhibitors. Furthermore, mutant Atg5-/- MEFs and PentaKO HeLa cells (human cervical adenocarcinoma with five autophagy receptor knockouts) were less sensitive to RCT cytotoxicity than their parental cell lines, indicating that RCT induces autophagy-mediated cell death. Taken together, these data indicate that RCT is a novel potential anti-liver cancer drug with a suppressive effect on CSCs

Piplartine eliminates CD34+ AML stem/progenitor cells by inducing oxidative stress and suppressing NF-κB signalling

Data availability: Data will be made available on request.Supplementary information is available online at: https://www.nature.com/articles/s41420-024-01909-4#Sec20 .Author notes: These authors contributed equally: Cristina Pina, Daniel P. Bezerra.Acute myeloid leukaemia (AML) is a haematological malignancy characterised by the accumulation of transformed myeloid progenitors in the bone marrow. Piplartine (PL), also known as piperlongumine, is a pro-oxidant small molecule extracted from peppers that has demonstrated antineoplastic potential in solid tumours and other haematological malignancies. In this work, we explored the potential of PL to treat AML through the use of a combination of cellular and molecular analyses of primary and cultured leukaemia cells in vitro and in vivo. We showed that PL exhibits in vitro cytotoxicity against AML cells, including CD34+ leukaemia-propagating cells, but not healthy haematopoietic progenitors, suggesting anti-leukaemia selectivity. Mechanistically, PL treatment increased reactive oxygen species (ROS) levels and induced ROS-mediated apoptosis in AML cells, which could be prevented by treatment with the antioxidant scavenger N-acetyl-cysteine and the pancaspase inhibitor Z-VAD(OMe)-FMK. PL treatment reduced NFKB1 gene transcription and the level of NF-κB p65 (pS536), which was depleted from the nucleus of AML cells, indicating suppression of NF-κB p65 signalling. Significantly, PL suppressed AML development in a mouse xenograft model, and its combination with current AML treatments (cytarabine, daunorubicin and azacytidine) had synergistic effects, indicating translational therapeutic potential. Taken together, these data position PL as a novel anti-AML candidate drug that can target leukaemia stem/progenitors and is amenable to combinatorial therapeutic strategies.This work received financial support and fellowships from the Brazilian agencies Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Brazil), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Brazil) and Fundação de Amparo à Pesquisa do Estado da Bahia (FAPESB, Brazil). Work in the Pina lab was funded by a British Society for Haematology Early-stage Research Grant (33932) and a BRIEF award by Brunel University London (2020–2022)

Syzygium jambolanum treatment improves survival in lethal sepsis induced in mice

<p>Abstract</p> <p>Background</p> <p>The leaves and the fruits from <it>Syzygium jambolanum </it>DC.(Myrtaceae), a plant known in Brazil as sweet olive or 'jambolão', have been used by native people to treat infectious diseases, diabetes, and stomachache. Since the bactericidal activity of <it>S. jambolanum </it>has been confirmed <it>in vitro</it>, the aim of this work was to evaluate the effect of the prophylactic treatment with <it>S. jambolanum </it>on the <it>in vivo </it>polymicrobial infection induced by cecal ligation and puncture (CLP) in mice.</p> <p>Methods</p> <p>C57Bl/6 mice were treated by the subcutaneous route with a hydroalcoholic extract from fresh leaves of <it>S. jambolanum </it>(HCE). After 6 h, a bacterial infection was induced in the peritoneum using the lethal CLP model. The mice were killed 12 h after the CLP induction to evaluate the cellular influx and local and systemic inflammatory mediators' production. Some animals were maintained alive to evaluate the survival rate.</p> <p>Results</p> <p>The prophylactic HCE treatment increased the mice survival, the neutrophil migration to infectious site, the spreading ability and the hydrogen peroxide release, but decreased the serum TNF and nitrite. Despite the increased migration and activation of peritoneal cells the HCE treatment did not decrease the number of CFU. The HCE treatment induced a significant decrease on the bone marrow cells number but did not alter the cell number of the spleen and lymph node.</p> <p>Conclusion</p> <p>We conclude that the treatment with <it>S. jambolanum </it>has a potent prophylactic anti-septic effect that is not associated to a direct microbicidal effect but it is associated to a recruitment of activated neutrophils to the infectious site and to a diminished systemic inflammatory response.</p

Relação entre aleitamento materno e hábitos de sucção não nutritivos

Este estudo objetivou identificar o tipo e o período de tempo de aleitamento recebido por crianças e verificar a associação com hábitos de sucção não nutritivos. Trata-se de um estudo transversal, retrospectivo, no qual foi aplicado um questionário em 330 mães ou responsáveis por crianças de 3 a 6 anos matriculadas em pré-escolas de Araçatuba (SP), após consentimento livre e esclarecido. Observou-se que 86,4% das mães amamentaram seus filhos. Quanto ao período de tempo, apenas 33,4% delas amamentaram exclusivamente no peito após seis meses de vida. O tempo médio de amamentação materna exclusiva recebida foi 3,84 meses e o de aleitamento complementar foi de 11,68 meses. Do total, 53,3% relataram que os filhos apresentavam hábitos de sucção não nutritivos, e destes 70,45% não foram amamentados exclusivamente no peito durante os seis primeiros meses de vida, existindo associação significativa entre os dois (pThis study sought to identify the type and duration of breastfeeding received by children and establish the association with non-nutritive suction habits. A retrospective, transversal study was conducted using a questionnaire given to 330 mothers or persons responsible for 3 to 6-year-old children registered in kindergartens in Araçatuba, State of São Paulo, after obtaining their free and informed consent. It was revealed that 86.4% of mothers breastfed their children. With respect to duration, only 33.4% of these mothers breastfed exclusively after 6 months. The average time of exclusive breastfeeding received by children was 3.84 months and complementary breastfeeding was 11.68 months. Of this total, 53.3% reported that their infants manifested non-nutritive suction habits and of these children, 70.45% were not exclusively breastfed for the first 6 months, there being a significant association between both (p<=0.05). Pacifier use was the most frequent habit (44.4%), showing a statistically significant association with breastfeeding time (p<0.0001). It was concluded that breastfeeding was practiced, albeit for a lesser duration than considered indispensable for the baby's development, there being an association between duration and type of breastfeeding and non-nutritive suction habits

Dre-miR-2188 Targets Nrp2a and Mediates Proper Intersegmental Vessel Development in Zebrafish Embryos

BACKGROUND: MicroRNAs (miRNAs) are a class of small RNAs that are implicated in the control of eukaryotic gene expression by binding to the 3'UTR of target mRNAs. Several algorithms have been developed for miRNA target prediction however, experimental validation is still essential for the correct identification of miRNA targets. We have recently predicted that Neuropilin2a (Nrp2a), a vascular endothelial growth factor receptor which is essential for normal developmental angiogenesis in zebrafish, is a dre-miR-2188 target. METHODOLOGY: Here we show that dre-miR-2188 targets the 3'-untranslated region (3'UTR) of Nrp2a mRNA and is implicated in proper intersegmental vessel development in vivo. Over expression of miR-2188 in zebrafish embryos down regulates Nrp2a expression and results in intersegmental vessel disruption, while its silencing increases Nrp2a expression and intersegmental vessel sprouting. An in vivo GFP sensor assay based on a fusion between the GFP coding region and the Nrp2a 3'UTR confirms that miR-2188 binds to the 3'UTR of Nrp2a and inhibits protein translation. CONCLUSIONS: We demonstrate that miR-2188 targets Nrp2a and affects intersegmental vessel development in zebrafish embryos