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Tomato (Solanum lycopersicum L.) is rich in nutrients and has been an important target for enhancing the accumulation of various metabolites. Tomato also contains cholesterol-derived molecules, steroidal glycoalkaloids (SGAs), which contribute to pathogen defence but are toxic to humans and considered anti-nutritional compounds. Previous studies suggest the role of various transcription factors in SGA biosynthesis; however, the role of light and associated regulatory factors has not been studied in tomato. Here, we demonstrated that SGA biosynthesis is regulated by light through the ELONGATED HYPOCOTYL 5 homolog, SlHY5, by binding to light-responsive G-boxes present in the promoters of structural and regulatory genes. SlHY5 complemented Arabidopsis (Arabidopsis thaliana) and tobacco (Nicotiana tabacum) hy5 mutants at molecular, morphological, and biochemical levels. CRISPR/Cas9-based knockout tomato plants, SlHY5CR, showed down-regulation of SGA and phenylpropanoid pathway genes, leading to a significant reduction in SGA (α-tomatine and dehydrotomatine) and flavonol contents, whereas plants overexpressing SlHY5 (SlHY5OX) showed the opposite effect. Enhanced SGA and flavonol levels in SlHY5OX lines provided tolerance against Alternaria solani fungus, while SlHY5CR lines were susceptible to the pathogen. This study advances our understanding of the HY5-dependent light-regulated biosynthesis of SGAs and flavonoids and their role in biotic stress in tomatoes.
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A/B testing is widely used to tune search and recommendation algorithms, to compare product variants as efficiently and effectively as possible, and even to study animal behavior. With ongoing investment, due to diminishing returns, the items produced by the new alternative B show smaller and smaller improvement in quality from the items produced by the current system A. By formalizing this observation, we develop closed-form analytical expressions for the sample efficiency of a number of widely used families of slate-based comparison tests. In empirical trials, these theoretical sample complexity results are shown to be predictive of real-world testing efficiency outcomes. These findings offer opportunities for both more cost-effective testing and a better analytical understanding of the problem.
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This review summarizes the structural and synthetic aspects of heterocyclic molecules incorporating an atom of a hypervalent main-group element. The term "hypervalent" has been suggested for derivatives of main-group elements with more than eight valence electrons, and the concept of hypervalency is commonly used despite some criticism from theoretical chemists. The significantly higher thermal stability of hypervalent heterocycles compared to their acyclic analogs adds special features to their chemistry, particularly for bromine and iodine. Heterocyclic compounds of elements with double bonds are not categorized as hypervalent molecules owing to the zwitterionic nature of these bonds, resulting in the conventional 8-electron species. This review is focused on hypervalent heterocyclic derivatives of nonmetal main-group elements, such as boron, silicon, nitrogen, carbon, phosphorus, sulfur, selenium, bromine, chlorine, iodine(III) and iodine(V).
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The nanoscale arrangement of ligands can have a major effect on the activation of membrane receptor proteins and thus cellular communication mechanisms. Here we report on the technological development and use of tailored DNA origami-based molecular rulers to fabricate "Multiscale Origami Structures As Interface for Cells" (MOSAIC), to enable the systematic investigation of the effect of the nanoscale spacing of epidermal growth factor (EGF) ligands on the activation of the EGF receptor (EGFR). MOSAIC-based analyses revealed that EGF distances of about 30-40 nm led to the highest response in EGFR activation of adherent MCF7 and Hela cells. Our study emphasizes the significance of DNA-based platforms for the detailed investigation of the molecular mechanisms of cellular signaling cascades.
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Fator de Crescimento Epidérmico , Receptores ErbB , Humanos , DNA/química , Fator de Crescimento Epidérmico/química , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Células HeLa , Ligantes , Transdução de SinaisRESUMO
Recent studies propose that primary transcripts of miRNAs (pri-miRNAs) contain small Open Reading Frames (ORFs) capable of encoding miRNA-encoded peptides (miPEPs). These miPEPs can function as transcriptional regulators for their corresponding pri-miRNAs, ultimately enhancing mature miRNA accumulation. Notably, pri-miR408 encodes the functional peptide miPEP408, regulating expression of miR408 and its target genes, providing plant tolerance to stresses. While miPEPs are crucial regulators, the factors governing them are have not been studied in detail. Here, we explored the light-dependent regulation of miPEP408 in Arabidopsis. Expression analysis during dark-light transitions revealed light-induced transcription and accumulation of the miPEP408. As the promoter of miR408 contains cis-acting elements responsible for binding to the bZIP-type transcription factor ELONGATED HYPOCOTYL5 (HY5), known for light-mediated regulation in plants, we studied its involvement in the regulation of miR408. Analysis of HY5 mutant (hy5-215), complemented line (HY5OX/hy5), and CONSTITUTIVE PHOTOMORPHOGENIC 1 mutant (cop1-4) plants supported HY5's positive regulation of miPEP408. Grafting and GUS assays further suggested the role of HY5 as a shoot-root mobile signal inducing light-dependent miPEP408 expression. This study underscores the regulatory impact of light on small peptides, exemplified by miPEP408, mediated by the key transcription factor HY5.
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Proteínas de Arabidopsis , Arabidopsis , MicroRNAs , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ligação Proteica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
MicroRNAs (miRNAs) are small non-coding RNAs that play a central role in regulating various developmental and biological processes. The expression of miRNAs is differentially modulated in response to various biotic and abiotic stresses. Recent findings have shown that some pri-miRNAs encode small regulatory peptides known as microRNA-encoded peptides (miPEPs). miPEPs regulate the growth and development of plants by modulating corresponding miRNA expression; however, the role of these peptides under different stress conditions remains unexplored. Here, we report that pri-miR408 encodes a small peptide, miPEP408, that regulates the expression of miR408, its targets, and associated phenotype in Arabidopsis. We also report that miR408, apart from Plantacyanin (ARPN) and Laccase3 (LAC3), targets a glutathione S-transferase (GSTU25) that plays a role in sulfur assimilation and exhibits a range of detoxification activities with the environmental pollutant. Plants overexpressing miR408 showed severe sensitivity under low sulfur (LS), arsenite As(III), and LS + As(III) stress, while miR408 mutants developed using the CRISPR/Cas9 approach showed tolerance. Transgenic lines showed phenotypic alteration and modulation in the expression of genes involved in the sulfur reduction pathway and affect sulfate and glutathione accumulation. Similar to miR408 overexpressing lines, the exogenous application of synthetic miPEP408 and miPEP408OX lines led to sensitivity in plants under LS, As(III), and combined LS + As(III) stress compared to the control. This study suggests the involvement of miR408 and miPEP408 in heavy metal and nutrient deficiency responses through modulation of the sulfur assimilation pathway.
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Arabidopsis , Arsênio , Fenômenos Biológicos , MicroRNAs , Arabidopsis/metabolismo , Arsênio/toxicidade , Arsênio/metabolismo , Estresse Fisiológico/genética , Glutationa/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Enxofre/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Throughout evolution, plants have developed strategies to confront and alleviate the detrimental impacts of abiotic stresses on their growth and development. The combat strategies involve intricate molecular networks and a spectrum of early and late stress-responsive pathways. Plant peptides, consisting of fewer than 100 amino acid residues, are at the forefront of these responses, serving as pivotal signalling molecules. These peptides, with roles similar to phytohormones, intricately regulate plant growth, development and facilitate essential cell-to-cell communications. Numerous studies underscore the significant role of these small peptides in coordinating diverse signalling events triggered by environmental challenges. Originating from the proteolytic processing of larger protein precursors or directly translated from small open reading frames, including microRNA (miRNA) encoded peptides from primary miRNA, these peptides exert their biological functions through binding with membrane-embedded receptor-like kinases. This interaction initiates downstream cellular signalling cascades, often involving major phytohormones or reactive oxygen species-mediated mechanisms. Despite these advances, the precise modes of action for numerous other small peptides remain to be fully elucidated. In this review, we delve into the dynamics of stress physiology, mainly focusing on the roles of major small signalling peptides, shedding light on their significance in the face of changing environmental conditions.
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Reguladores de Crescimento de Plantas , Plantas , Reguladores de Crescimento de Plantas/metabolismo , Plantas/metabolismo , Desenvolvimento Vegetal , Peptídeos/metabolismo , Estresse Fisiológico/genéticaRESUMO
Owing to their high reactivity and selectivity, variations in the spin ground state and a range of possible pathways, high-valent FeIV =O species are popular models with potential bioinspired applications. An interesting example of a structure-reactivity pattern is the detailed study with five nonheme amine-pyridine pentadentate ligand FeIV =O species, including N4py: [(L1 )FeIV =O]2+ (1), bntpen: [(L2 )FeIV =O]2+ (2), py2 tacn: [(L3 )FeIV =O]2+ (3), and two isomeric bispidine derivatives: [(L4 )FeIV =O]2+ (4) and [(L5 )FeIV =O]2+ (5). In this set, the order of increasing reactivity in the hydroxylation of cyclohexane differs from that with cyclohexadiene as substrate. A comprehensive DFT, ab initio CASSCF/NEVPT2 and DLPNO-CCSD(T) study is presented to untangle the observed patterns. These are well reproduced when both activation barriers for the C-H abstraction and the OH rebound are taken into account. An MO, NBO and deformation energy analysis reveals the importance of π(pyr) â π*xz (FeIII -OH) electron donation for weakening the FeIII -OH bond and thus reducing the rebound barrier. This requires that pyridine rings are oriented perpendicularly to the FeIII -OH bond and this is a subtle but crucial point in ligand design for non-heme iron alkane hydroxylation.
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PURPOSE: To compare disease-free survival (DFS), overall survival (OS), and adverse events (AEs) among muscle-invasive urothelial carcinoma (MIUC) patients receiving adjuvant immune checkpoint inhibitors (ICIs) versus placebo/observation following radical surgery. METHODS: This was a systematic review/meta-analysis of all published phase 3 randomized controlled trials. MEDLINE, EMBASE, and Cochrane were searched from inception until April 4, 2024. Pooled hazard ratios (HR) and relative risks (RR), plus confidence intervals (CI), were generated using frequentist random-effects modeling. RESULTS: Three trials were identified: IMvigor010, CheckMate 274, and AMBASSADOR. In the overall cohort, adjuvant ICIs significantly improved DFS by 23% (HR = 0.77, 95% CI = 0.65-0.90). No DFS benefit was observed in patients with upper tract disease (HR = 1.19, 95% CI = 0.86-1.64). The highest magnitude of DFS benefit was observed among patients who had received prior neoadjuvant chemotherapy (HR = 0.69) and pathologic node-positive disease (HR = 0.75). A similar DFS benefit was observed irrespective of tumor PD-L1 status. Pooled OS demonstrated a 13% non-significant benefit (HR = 0.87, 95% CI = 0.75-1.01). Grade ≥ 3 immune-mediated AEs occurred in 8.6% and 2.1% of ICI and placebo/observation patients, respectively (RR = 4.35, 95% CI = 1.02-18.5). AEs leading to treatment discontinuation occurred in 14.3% and 0.9% of patients, respectively. CONCLUSION: Adjuvant ICIs confer a DFS benefit following radical surgery for MIUC, particularly among node-positive patients and those who received prior neoadjuvant chemotherapy. The lack of benefit for upper tract disease suggests that alternate adjuvant approaches, including chemotherapy, should be considered for these patients. Tumor PD-L1 status is not a predictive biomarker, highlighting the need for biomarkers in this setting.
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Carcinoma de Células de Transição , Inibidores de Checkpoint Imunológico , Neoplasias da Bexiga Urinária , Humanos , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/cirurgia , Quimioterapia Adjuvante , Inibidores de Checkpoint Imunológico/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxa de Sobrevida , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgiaRESUMO
Bacterial strain H4R21T was isolated from beech rhizosphere soil sampled in the forest experimental site of Montiers (Meuse, France). It effectively weathers minerals, hydrolyses chitin and produces quorum sensing signal molecules. The strain is aerobic and Gram-stain-negative. Phylogenetic analysis based on its 16S rRNA gene sequence indicated that strain H4R21T belongs to the genus Collimonas with high sequence similarity to C. arenae Ter10T (99.38â%), C. fungivorans Ter6T(98.97â%), C. pratensis Ter91T (98.76â%), C. humicola RLT1W51T (98.46â%) and C. silvisoli RXD178 T (98.46â%), but less than 98â% similarity to other strains of the genus Collimonas. The predominant quinone in H4R21T is ubiquinone-8 (Q8). The major polar lipids are diphosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and lipid. The major fatty acids identified were C12â:â0, C12:0 3-OH, C16ââ:ââ0 and C17:0âcyclo. The digital DNA G+C content of the genomic DNA was 59.5âmol%. Furthermore, the strain could be clearly distinguished from its closely related type strains by a combination of phylogenomic and in silico DNA-DNA hybridization results, and phenotypic characteristics. Therefore, strain H4R21T represents a novel species within the genus Collimonas, for which the name Collimonas rhizosphaerae sp. nov. is proposed, with strain H4R21T (=CFBP 9203T=DSM 117599T) as the type strain.
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Fagus , Filogenia , Rizosfera , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Fagus/microbiologia , Ácidos Graxos , França , Hibridização de Ácido Nucleico , Fosfolipídeos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , UbiquinonaRESUMO
AIMS: Geophytic plants have evolved to develop underground storage organs (USO) in the active growing season to withstand harsh environments as well as to coordinate growth and reproduction when conditions are favourable. Saffron is an autumn flowering geophyte and an expensive spice crop restricted to certain geographical locations in the world. Saffron, being sterile, does not produce seeds and thus propagates only through corms, the quality of which determines its yield. Corm development in saffron is unexplored and the underlying molecular mechanism is still elusive. In this study, we performed an extensive characterisation of the transcriptional dynamics in the source (leaf) and sink (corm) tissues during corm development in saffron. KEY RESULTS: Via morphological and transcriptome studies, we identified molecular factors regulating corm development process in saffron, which defined corm development into three stages: the initiation stage demonstrates enhanced vegetative growth aboveground and swelling of shoot base belowground due to active cell division & carbohydrate storage; the bulking stage comprises of increased source and sink strength, active photosynthesis, circadian gating and starch accumulation; the maturation stage represents reduced source and sink strength, lowered photosynthesis, sugar transport, starch synthesis and cell cycle arrest. UTILITY: The global view of transcriptional changes in source and sink identifies similar and new molecular factors involved in the saffron corm development process compared to USO formation in other geophytes and provides a valuable resource for dissecting the molecular network underlying the corm development. We propose a hypothetical model based on data analysis, of how molecular factors via environmental cues can regulate the corm development process in saffron.
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Crocus , Crocus/genética , Crocus/metabolismo , Transcriptoma/genética , Folhas de Planta , Amido/metabolismoRESUMO
Reported are the synthesis and detailed studies of the iron(IV)-tosylimido complexes of two isomeric pentadentate bispidine ligands (bispidines are 3,7-diazabicyclo[3.3.1]nonane derivatives). This completes a series of five tosylimido complexes with comparable pentadentate amine/pyridine ligands, where the corresponding [(L)FeIVâO]2+ oxidants have been studied in detail. The characterization of the two new complexes in solution (UV-vis-NIR, Mössbauer, HR-ESI-MS) shows that these oxidants have an intermediate spin (S = 1) electronic ground state. The reactivities have been studied as oxidants in C-H activation at 1,3-cyclohexadiene and nitrogen atom transfer to thioanisole. For the latter substrate, the entire set of data for the five ligands and for both nitrogen and oxygen atom transfer is now available and the interesting observation is that oxygen atom transfer is, as expected, generally faster than nitrogen atom transfer, with the exception of the two ligands that have four and three pyridine groups oriented parallel to the Fe-O and Fe-N axes. A thorough DFT analysis indicates that this is due to steric effects in the case of the [(L)FeIVâO]2+ species, which are less important in the [(L)FeIVâNTs]2+ compounds due to partial electron transfer from the thioanisole substrate to the iron(IV)-tosylimido oxidant.
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Designing highly active and robust earth abundant trifunctional electrocatalysts for energy storage and conversion applications remain an enormous challenge. Herein, we report a trifunctional electrocatalyst (CrCo/CoN4@CNT-5), synthesized at low calcination temperature (550 °C), which consists of Co-N4 single atom and CrCo alloy nanoparticles and exhibits outstanding electrocatalytic performance for the hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction. The catalyst is able to deliver a current density of 10 mA cm-2 in an alkaline electrolytic cell at a very low cell voltage of â¼1.60 V. When the catalyst is equipped in a liquid rechargeable Zn-air battery, it endowed a high open-circuit voltage with excellent cycling durability and outperformed the commercial Pt/C+IrO2 catalytic system. Furthermore, the Zn-air battery powered self-driven water splitting system is displayed using CrCo/CoN4@CNT-5 as sole trifunctional catalyst, delivering a high H2 evolution rate of 168 µmol h-1. Theoretical calculations reveal synergistic interaction between Co-N4 active sites and CrCo nanoparticles, favoring the Gibbs free energy for H2 evolution. The presence of Cr not only enhances the H2O adsorption and dissociation but also tunes the electronic property of CrCo nanoparticles to provide optimized hydrogen binding capacity to Co-N4 sites, thus giving rise to accelerated H2 evolution kinetics. This work highlights the importance of the presence of small quantity of Cr in enhancing the electrocatalytic activity as well as robustness of single-atom catalyst and suggests the design of the multifunctional robust electrocatalysts for long-term H2 evolution application.
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We report a competent and selective hydrosilylation of nitriles and tertiary amides catalyzed by the readily available zinc bis(hexamethyldisilazide) under solvent-free and mild conditions, making it a sustainable and desirable alternative to existing methods. Both protocols afforded high conversion, superior selectivity, and a broad substrate scope, from electron-withdrawing to electron-donating and heterocyclic substitutions.
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Copper iodide, an environmentally friendly material abundant in nature, holds great significance for room temperature thermoelectric (TE) applications owing to its high Seebeck coefficient and optical transparency. However, to fully unlock its thermoelectric potential and match the performance of conventional TE materials, there is a need to further enhance its electrical conductivity. In this study, we have successfully synthesized nano-crystalline powders of both undoped and aluminium-doped CuI at room temperature using the chemical precipitation method in an ethanol medium. The concentration of aluminium dopant has been optimized to maximize TE performance. At 400 K, the highest TE power factor and figure of merit achieved are 79 µW m-1 K-2 and 0.08, respectively, for CuI doped with 0.1 mol% Al. This enhancement in TE properties can be attributed to the increased carrier density resulting from aluminium doping. The impact of aluminium doping on the temperature-dependent thermal conductivity has been investigated, and the findings are explained by the decay mechanism of optical phonons, supported by the anharmonic phonon coupling theory. Our work delves into the evolution of structural, thermal, optical, and TE properties of CuI upon aluminium (Al) doping. The results provide valuable insights into the future application of CuI in transparent thermoelectric and optoelectronic fields.
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This article investigates the relaxation dynamics of the ionized 2a1 state of a water molecule within a water dimer. The study was motivated by findings from two previous pieces of research that focused on the relaxation behaviors of the inner-valence ionized water dimer. The present study discloses an observation indicating that water dimers display specific fragmentation patterns following inner-valence ionization, depending on the position of the vacancy. Vacancies were created in the 2a1 state of the proton-donating water molecule (PDWM) and proton-accepting water molecule (PAWM). Utilizing Born-Oppenheimer molecular dynamics simulations, the propagation of the 2a1 ionized state was carried out for both scenarios. The results revealed proton transfer occurred when the vacancy resided in the PDWM, accompanied by the closing of decay channels for O-H bond distance (RO-H) > 1.187 Š(matching Richter et al.'s findings). Conversely, when vacancy was on PAWM, we observed no closing of decay channels (aligning with Jahnke et al.'s findings). This difference translates to distinct fragmentation pathways. In PDWM cases, 2a1 state ionization leads to H3O+ -OH⢠formation. In contrast, PAWM vacancies result in decay pathways leading to H2O+-H2O+ products.
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Herbicides are applied for effective weed management in order to increase the crop yield. In recent decades, the overuse of these chemicals has posed adverse effects on different biotic components of the environment. Pretilachlor has been widely used during last few decades for weed management in paddy crop. Its excessive use may prove fatal for environment, various organisms, and nontarget plants. Thus, it is pertinent to know the extent to which herbicide residues remain in environment. The potential mobility and the release rate of herbicide in the soil are important factors governing ecotoxicological impact and degradation rate. Therefore, several techniques are being investigated for its effective removal from the contaminated sites. Furthermore, efforts have also been made to study the degradation of pretilachlor by various physicochemical processes, resulting into the formation of different types of metabolites. This review summarizes the available information on environmental fate, various degradation processes, microbial biotransformation, metabolites formed, ecotoxicological effects, techniques for detection in environmental samples, effect of safener, and various control release formulations for sustained release of pretilachlor in applied fields. The information so obtained will be very advantageous in deciding the future policies for safe and judicious use of the herbicide by maintaining health and environmental sustainability.
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Herbicidas , Herbicidas/toxicidade , Solo/química , Acetanilidas/químicaRESUMO
The objective of the present study was to identify genomic regions influencing economic traits in Murrah buffaloes using weighted single step Genome Wide Association Analysis (WssGWAS). Data on 2000 animals, out of which 120 were genotyped using a double digest Restriction site Associated DNA (ddRAD) sequencing approach. The phenotypic data were collected from NDRI, India, on growth traits, viz., body weight at 6M (month), 12M, 18M and 24M, production traits like 305D (day) milk yield, lactation length (LL) and dry period (DP) and reproduction traits like age at first calving (AFC), calving interval (CI) and first service period (FSP). The biallelic genotypic data consisted of 49353 markers post-quality check. The heritability estimates were moderate to high, low to moderate, low for growth, production, reproduction traits, respectively. Important genomic regions explaining more than 0.5% of the total additive genetic variance explained by 30 adjacent SNPs were selected for further analysis of candidate genes. In this study, 105 genomic regions were associated with growth, 35 genomic regions with production and 42 window regions with reproduction traits. Different candidate genes were identified in these genomic regions, of which important are OSBPL8, NAP1L1 for growth, CNTNAP2 for production and ILDR2, TADA1 and POGK for reproduction traits.
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Búfalos , Estudo de Associação Genômica Ampla , Feminino , Animais , Búfalos/genética , Lactação/genética , Genoma/genética , Leite , Genômica , Fenótipo , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
Chronic diseases like cancer and diabetes are the major public health concerns of India and worldwide. Nowadays, plant-derived products are in great demand for the treatment of these diseases. Pumpkin seeds are traditionally implicated for their pharmacological properties, as exemplified by benign prostatic hyperplasia. Earlier, pumpkin seed proteins were extracted by the Osborne method, and their functional and nutritional qualities were evaluated. Here, the aim is to assess in vitro, the anticancer and antidiabetic properties of seed protein fractions. HepG2, MDA-MB-231, and MCF-7 cell lines were treated with water-soluble (WF) and alkali-soluble fractions (AF) to assess cytotoxicity, while pancreatic ß-cells and insulin resistance (IR) - HepG2 cell lines were treated with WF to evaluate the antidiabetic potential. WF and AF showed cytotoxic effects towards HepG2 and MDA-MB-231 cell lines, suggesting apoptosis-mediated anticancerous activity. WF potentiates glucose-stimulated insulin secretion in pancreatic ß-cells, in a dose-dependent manner. In IR-HepG2 cell line studies, control, metformin, and WF-treated groups showed uptake of glucose, when compared to the diabetic group, which is well-correlated with the upregulated expressions of GLUT2 and GLUT4 transporters in these groups. These results indicate that proteins from WF and AF may have anticancerous and antidiabetic properties and thus have the potential to utilize pumpkin proteins in the management of cancer and diabetes.
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Interest is growing in transition metal-free compounds for small molecule activation and catalysis. We discuss the opportunities arising from synthesizing sodium-doped amorphous silicon-boron-nitride (Na-doped a-SiBN). Na+ cations and 3-fold coordinated BIII moieties were incorporated into an amorphous silicon nitride network via chemical modification of a polysilazane followed by pyrolysis in ammonia at 1000 °C. Emphasis is placed on the mechanisms of hydrogen (H2) activation within Na-doped a-SiBN structure. This material design approach allows the homogeneous distribution of Na+ and BIII moieties surrounded by SiN4 units contributing to the transformation of the BIII moieties into 4-fold coordinated geometry upon encountering H2, potentially serving as frustrated Lewis acid (FLA) sites. Exposure to H2 induced formation of frustrated Lewis base (FLB) N-= sites with Na+ as a charge-compensating cation, resulting in the in situ formation of a frustrated Lewis pair (FLP) motif (≡BFLA···Hδ-···Hδ+···:N-(Na+)=). Reversible H2 adsorption-desorption behavior with high activation energy for H2 desorption (124 kJ mol-1) suggested the H2 chemisorption on Na-doped a-SiBN. These findings highlight a future landscape full of possibilities within our reach, where we anticipate main-group-mediated small molecule activation will have an important impact on the design of more efficient catalytic processes and the discovery of new catalytic transformations.