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1.
Front Fungal Biol ; 5: 1418145, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39309730

RESUMO

Over a billion years of fungal evolution has enabled representatives of this kingdom to populate almost all parts of planet Earth and to adapt to some of its most uninhabitable environments including extremes of temperature, salinity, pH, water, light, or other sources of radiation. Cryomyces antarcticus is an endolithic fungus that inhabits rock outcrops in Antarctica. It survives extremes of cold, humidity and solar radiation in one of the least habitable environments on Earth. This fungus is unusual because it produces heavily melanized, meristematic growth and is thought to be haploid and asexual. Due to its growth in the most extreme environment, it has been suggested as an organism that could survive on Mars. However, the mechanisms it uses to achieve its extremophilic nature are not known. Comparative genomics can provide clues to the processes underlying biological diversity, evolution, and adaptation. This effort has been greatly facilitated by the 1000 Fungal Genomes project and the JGI MycoCosm portal where sequenced genomes have been assembled into phylogenetic and ecological groups representing different projects, lifestyles, ecologies, and evolutionary histories. Comparative genomics within and between these groups provides insights into fungal adaptations, for example to extreme environmental conditions. Here, we analyze two Cryomyces genomes in the context of additional psychrophilic fungi, as well as non-psychrophilic fungi with diverse lifestyles selected from the MycoCosm database. This analysis identifies families of genes that are expanded and contracted in Cryomyces and other psychrophiles and may explain their extremophilic lifestyle. Higher GC contents of genes and of bases in the third positions of codons may help to stabilize DNA under extreme conditions. Numerous smaller contigs in C. antarcticus suggest the presence of an alternative haplotype that could indicate the sequenced isolate is diploid or dikaryotic. These analyses provide a first step to unraveling the secrets of the extreme lifestyle of C. antarcticus.

2.
World J Methodol ; 14(3): 91058, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39310236

RESUMO

BACKGROUND: Hepatitis C virus (HCV) infection progresses through various phases, starting with inflammation and ending with hepatocellular carcinoma. There are several invasive and non-invasive methods to diagnose chronic HCV infection. The invasive methods have their benefits but are linked to morbidity and complications. Thus, it is important to analyze the potential of non-invasive methods as an alternative. Shear wave elastography (SWE) is a non-invasive imaging tool widely validated in clinical and research studies as a surrogate marker of liver fibrosis. Liver fibrosis determination by invasive liver biopsy and non-invasive SWE agree closely in clinical studies and therefore both are gold standards. AIM: To analyzed the diagnostic efficacy of non-invasive indices [serum fibronectin, aspartate aminotransferase to platelet ratio index (APRI), alanine aminotransferase ratio (AAR), and fibrosis-4 (FIB-4)] in relation to SWE. We have used an Artificial Intelligence method to predict the severity of liver fibrosis and uncover the complex relationship between non-invasive indices and fibrosis severity. METHODS: We have conducted a hospital-based study considering 100 untreated patients detected as HCV positive using a quantitative Real-Time Polymerase Chain Reaction assay. We performed statistical and probabilistic analyses to determine the relationship between non-invasive indices and the severity of fibrosis. We also used standard diagnostic methods to measure the diagnostic accuracy for all the subjects. RESULTS: The results of our study showed that fibronectin is a highly accurate diagnostic tool for predicting fibrosis stages (mild, moderate, and severe). This was based on its sensitivity (100%, 92.2%, 96.2%), specificity (96%, 100%, 98.6%), Youden's index (0.960, 0.922, 0.948), area under receiver operating characteristic curve (0.999, 0.993, 0.922), and Likelihood test (LR+ > 10 and LR- < 0.1). Additionally, our Bayesian Network analysis revealed that fibronectin (> 200), AAR (> 1), APRI (> 3), and FIB-4 (> 4) were all strongly associated with patients who had severe fibrosis, with a 100% probability. CONCLUSION: We have found a strong correlation between fibronectin and liver fibrosis progression in HCV patients. Additionally, we observed that the severity of liver fibrosis increases with an increase in the non-invasive indices that we investigated.

3.
Chem Commun (Camb) ; 60(77): 10776-10779, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39252561

RESUMO

We report the design, synthesis, photoswitching and computational studies of N-methyl arylazo-3,5-(di-2-pyridyl)pyrazole and its N-alkyl pyridinium derivatives with an ionic center proximally located to the azo group. Besides achieving excellent photoswitching characteristics, particularly at longer wavelengths, and tuning Z isomer stability due to the effects of counter ions and pH, the utility of neutral and ionic photoswitches for pH modulation by light was achieved.

4.
Breed Sci ; 74(1): 37-46, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39246437

RESUMO

We review the undertaking of a field trial of low asparagine wheat lines in which the asparagine synthetase gene, TaASN2, has been knocked out using CRISPR/Cas9. The field trial was undertaken in 2021-2022 and represented the first field release of genome edited wheat in Europe. The year of the field trial and the period since have seen rapid changes in the regulations covering both the field release and commercialisation of genome edited crops in the UK. These historic developments are reviewed in detail. Free asparagine is the precursor for acrylamide formation during high-temperature cooking and processing of grains, tubers, storage roots, beans and other crop products. Consequently, work on reducing the free asparagine concentration of wheat and other cereal grains, as well as the tubers, beans and storage roots of other crops, is driven by the need for food businesses to comply with current and potential future regulations on acrylamide content of foods. The topic illustrates how strategic and applied crop research is driven by regulations and also needs a supportive regulatory environment in which to thrive.

5.
ACS Appl Mater Interfaces ; 16(37): 49790-49800, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39231029

RESUMO

Today's extensive use of inorganic fertilizers in agricultural techniques has increased the concentration of nitrate in drinking water beyond safety limits, causing serious health problems in humans such as thyroidism and methemoglobinemia. Therefore, the present work describes the synthesis of a benzimidazolium salt-based fluorescent chemosensor (KG3) via a multistep synthesis which detects nitrate ions in aqueous medium. This was validated using various analytical techniques such as fluorescence spectroscopy, UV-visible spectroscopy, and electrochemical studies with a detection limit of 0.032 µM without any interference from other active water pollutants. Subsequently, KG3 is further modified with the help of iron oxide nanoparticles (Fe3O4 NPs) and silica to obtain the SiO2@Fe3O4-KG3 nanocomposite, which was immobilized over a polyether sulfone membrane and evaluated for removal of nitrate ions from groundwater with a removal efficiency of 96%. Moreover, the engineered composite membrane can serve as a solid-state fluorescence sensor to detect NO3- ions, which was demonstrated through a portable mobile-based prototype employing a hue, saturation, and value parameter model.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 325: 125042, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39232312

RESUMO

A novel fluorenone-naphthyl pendant sensor (FTU) possessing thiourea functionality has been synthesized via a simple condensation method and utilized for the recognition of F- and Hg2+ ions in the solution of CH3CN. The addition of F- and Hg2+ ions to the FTU solution led to the appearance of red-shifted absorption bands at 340 and 315 nm, respectively. On the other hand, in the fluorescence spectrum, the two-fold decrease in fluorescence intensity of probe FTU was observed with F- ions; while complete quenching of the fluorescence intensity was noticed with Hg2+ ions at 423 nm. The limit of detection values of F- and Hg2+ ions were found to be 1.02 & 29.1 nM, respectively, measured by UV-vis studies and 0.0185 & 0.81 nM, respectively, measured by fluorescence studies, which are less than recommended by WHO. DFT computational assessments and 1H NMR titration experiments pointed to F- induced deprotonation of thiourea NH signals. However, the chelation-enhanced quenching effect (CHEQ) was held responsible for fluorescence quenching with Hg2+ addition. Moreover, the in-situ formed FTU + F- complex was utilized for secondary sensing of drug sobisis. Furthermore, the real-world applicability of sensor FTU has been successfully scrutinized for the recognition of F- ions in the toothpaste samples. In addition, molecular docking studies revealed that FTU exhibited excellent antibacterial potency towards different gram-positive as well as negative strains.

7.
Lancet Glob Health ; 12(10): e1693-e1705, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39178880

RESUMO

The south Asian region (SAR) is home to 1·74 billion people, corresponding to 22% of the global population. The region faces several challenges pertaining to changing epidemiology, rapid urbanisation, and social and economic concerns, which affect health outcomes. Primary health care (PHC) is a cost-effective strategy to respond to these challenges through integrated service delivery, multi-sectoral action, and empowered communities. The PHC approach has historically been an important cornerstone of health policy in SAR countries. However, the region is yet to fully reap the benefits of PHC-oriented health systems. Our introductory paper in this Lancet Series on PHC in the SAR describes the existing PHC delivery structure in five SAR nations (ie, Bangladesh, India, Nepal, Pakistan, and Sri Lanka) and critically appraises PHC performance to identify its enablers and barriers. The paper proposes investing in a shared culture of innovation and collaboration for revitalisation of PHC in the region.


Assuntos
Atenção Primária à Saúde , Humanos , Atenção Primária à Saúde/organização & administração , Nepal , Ásia , Índia , Sri Lanka , Bangladesh , Paquistão , Política de Saúde , Ásia Meridional
8.
Bioconjug Chem ; 35(9): 1283-1299, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39207940

RESUMO

Lipid nanoparticles have been recognized as a powerful weapon for delivering various imaging and therapeutic agents to the localized solid tumors, especially brain tumors individually or in combination. Promisingly, lipid-based nanosystems have been considered as safe delivery systems which are even approved by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). One recent spotlight of lipid nanoparticles as COVID-19 mRNA vaccines where lipid nanoparticles play an important role in effectively protecting and delivering mRNA to the desired cells. As of now, successive progress in lipid-based nanocarriers, viz., nanoliposomes, solid lipid nanoparticles, ionizable lipid nanostructures, etc., with better biochemical and biophysical stabilities, has been noticed and reported. Moreover, lipid nanostructures have been considered as versatile therapeutics platforms for a variety of diseases due to their biocompatibility, ability to protect and deliver therapeutics to the localized site, and better reproducibility and reliability. However, lipid nanoparticles still face morphological and biochemical changes upon their in vivo administration. These changes alter the specific biological and pathological response of lipid nanoparticles during their personalized brain tumor theranostics. Second, lipid nanomedicine still faces major challenges of zero premature leakage of loaded cargo, long-term colloidal stability, and off targeting. Herein, various lipid-based nanomedicines for brain tumor imaging and therapeutics "theranostics" have been reviewed and summarized considering major aspects of preclinical and clinical studies. On the other hand, engineering and biological challenges of lipid theranostics systems with relevant advantages and guidelines for clinical practice for different brain tumors have also been discussed. This review provides in-depth knowledge of lipid nanoparticle-based theranostics agents for brain tumor imaging and therapeutics.


Assuntos
Neoplasias Encefálicas , Lipídeos , Nanopartículas , Nanomedicina Teranóstica , Humanos , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/diagnóstico por imagem , Nanomedicina Teranóstica/métodos , Nanopartículas/química , Lipídeos/química , Animais , COVID-19 , Lipossomos/química , Sistemas de Liberação de Medicamentos/métodos
9.
Stud Health Technol Inform ; 316: 1999-2003, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39176885

RESUMO

In Canada, extreme heat occurrences present significant risks to public health, particularly for vulnerable groups like older individuals and those with pre-existing health conditions. Accurately predicting indoor temperatures during these events is crucial for informing public health strategies and mitigating the adverse impacts of extreme heat. While current systems rely on outdoor temperature data, incorporating real-time indoor temperature estimations can significantly enhance decision-making and strengthen overall health system responses. Sensor-based technologies, such as ecobee smart thermostats installed in homes, enable effortless collection of indoor temperature and humidity data. This study evaluates the efficacy of deep learning models in predicting indoor temperatures during heat waves using smart thermostat data, to enhance public health responses. Utilizing ecobee smart thermostats, we analyzed indoor temperature trends and developed forecasting models. Our findings indicate the potential of integrating IoT and deep learning into health warning systems, enabling proactive interventions, and improving sustainable health care practices in extreme heat scenarios. This approach highlights the role of digital health innovations in creating the resilient and sustainable healthcare systems against climate-related health adversities.


Assuntos
Aprendizado Profundo , Previsões , Canadá , Humanos , Calor Extremo , Temperatura Alta , Habitação
10.
Plant Physiol Biochem ; 215: 109030, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39137683

RESUMO

Globally, metal/metalloid(s) soil contamination is a persistent issue that affects the atmosphere, soil, water and plant health in today's industrialised world. However, an overabundance of these transition ions promotes the excessive buildup of reactive oxygen species (ROS) and ion imbalance, which harms agricultural productivity. Plants employ several strategies to overcome their negative effects, including hyperaccumulation, tolerance, exclusion, and chelation with organic molecules. Polyamines (PAs) are the organic compounds that act as chelating agents and modulate various physiological, biochemical, and molecular processes under metal/metalloid(s) stress. Their catabolic products, including H2O2 and gamma amino butyric acid (GABA), are also crucial signalling molecules in abiotic stress situations, particularly under metal/metalloid(s) stress. In this review, we explained how PAs regulate genes and enzymes, particularly under metal/metalloid(s) stress with a specific focus on arsenic (As), boron (B), cadmium (Cd), chromium (Cr), and zinc (Zn). The PAs regulate various plant stress responses by crosstalking with other plant hormones, upregulating phytochelatin, and metallothionein synthesis, modulating stomatal closure and antioxidant capacity. This review presents valuable insights into how PAs use a variety of tactics to reduce the harmful effects of metal/metalloid(s) through multifaceted strategies.


Assuntos
Metaloides , Poliaminas , Poliaminas/metabolismo , Metaloides/metabolismo , Metaloides/toxicidade , Plantas/metabolismo , Plantas/efeitos dos fármacos , Metais/metabolismo , Metais/toxicidade , Estresse Fisiológico/efeitos dos fármacos
11.
Iran J Pathol ; 19(2): 160-169, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39118793

RESUMO

Background & Objective: p16 has different roles in the nuclear and cytoplasmic locations. The nuclear localization of the p16 protein explains its role in cell cycle regulation. Cytoplasmic expression was considered an artifact in the initial years, but there is evidence to prove that cytoplasmic localization is real and that p16 has different roles in the nuclear and cytoplasmic locations. We aimed to study the immunoexpression of p16 protein in the nuclear and cytoplasmic locations of the epithelial and stromal compartments of fibroadenoma, invasive breast carcinoma, and a select number of phyllodes tumors. Methods: The study included a total of 107 patients, comprising 51 cases of invasive breast carcinoma, 51 cases of fibroadenoma, 4 cases of benign phyllodes tumors, and 1 case of lobular carcinoma in situ (LCIS). The p16 immunohistochemistry was evaluated for nuclear and cytoplasmic localization in the epithelial and stromal compartments of the tumors. Results: Of the 51 fibroadenoma cases, 23 showed strong nuclear p16 epithelial expression, but no case showed cytoplasmic expression. In 19/51 cases, stromal cells also showed strong p16 nuclear expression. Moderate stromal p16 expression was observed in 3 out of 4 cases of benign phyllodes. Out of the 51 cases of invasive carcinoma, 31 showed moderate to strong nuclear p16 immunopositivity, while 27 cases exhibited cytoplasmic p16 expression. We found a statistically significant correlation between moderate to strong nuclear p16 immunoexpression and the molecular subtype of breast carcinoma. Conclusion: The cytoplasmic localization of p16 immunohistochemistry is not seen in epithelial components of fibroadenoma, while it is seen frequently in breast carcinoma. Nuclear p16 expression has a statistically significant correlation with molecular subtypes of breast carcinoma.

12.
NPJ Syst Biol Appl ; 10(1): 75, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013872

RESUMO

Mathematical models of biochemical reaction networks are an important and emerging tool for the study of cell signaling networks involved in disease processes. One promising potential application of such mathematical models is the study of how disease-causing mutations promote the signaling phenotype that contributes to the disease. It is commonly assumed that one must have a thorough characterization of the network readily available for mathematical modeling to be useful, but we hypothesized that mathematical modeling could be useful when there is incomplete knowledge and that it could be a tool for discovery that opens new areas for further exploration. In the present study, we first develop a mechanistic mathematical model of a G-protein coupled receptor signaling network that is mutated in almost all cases of uveal melanoma and use model-driven explorations to uncover and explore multiple new areas for investigating this disease. Modeling the two major, mutually-exclusive, oncogenic mutations (Gαq/11 and CysLT2R) revealed the potential for previously unknown qualitative differences between seemingly interchangeable disease-promoting mutations, and our experiments confirmed oncogenic CysLT2R was impaired at activating the FAK/YAP/TAZ pathway relative to Gαq/11. This led us to hypothesize that CYSLTR2 mutations in UM must co-occur with other mutations to activate FAK/YAP/TAZ signaling, and our bioinformatic analysis uncovers a role for co-occurring mutations involving the plexin/semaphorin pathway, which has been shown capable of activating this pathway. Overall, this work highlights the power of mechanism-based computational systems biology as a discovery tool that can leverage available information to open new research areas.


Assuntos
Mutação , Receptores Acoplados a Proteínas G , Transdução de Sinais , Humanos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Mutação/genética , Neoplasias Uveais/genética , Neoplasias Uveais/metabolismo , Biologia de Sistemas/métodos , Modelos Biológicos , Melanoma/genética , Melanoma/metabolismo , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo
13.
Sci Rep ; 14(1): 15433, 2024 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965354

RESUMO

The COVID-19 pandemic continues to challenge healthcare systems globally, necessitating advanced tools for clinical decision support. Amidst the complexity of COVID-19 symptomatology and disease severity prediction, there is a critical need for robust decision support systems to aid healthcare professionals in timely and informed decision-making. In response to this pressing demand, we introduce BayesCovid, a novel decision support system integrating Bayesian network models and deep learning techniques. BayesCovid automates data preprocessing and leverages advanced computational methods to unravel intricate patterns in COVID-19 symptom dynamics. By combining Bayesian networks and Bayesian deep learning models, BayesCovid offers a comprehensive solution for uncovering hidden relationships between symptoms and predicting disease severity. Experimental validation demonstrates BayesCovid 's high prediction accuracy (83.52-98.97%). Our work represents a significant stride in addressing the urgent need for clinical decision support systems tailored to the complexities of managing COVID-19 cases. By providing healthcare professionals with actionable insights derived from sophisticated computational analysis, BayesCovid aims to enhance clinical decision-making, optimise resource allocation, and improve patient outcomes in the ongoing battle against the COVID-19 pandemic.


Assuntos
Teorema de Bayes , COVID-19 , Aprendizado Profundo , Pandemias , COVID-19/epidemiologia , COVID-19/virologia , Humanos , SARS-CoV-2/isolamento & purificação , Sistemas de Apoio a Decisões Clínicas , Inteligência Artificial
14.
Br J Haematol ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978231

RESUMO

Sickle cell disease (SCD) is one of the most common genetic disorders in the world predominantly affecting economically disadvantaged populations. There is a notable discrepancy between the growing adult SCD population and available diagnostic and therapeutic interventions for SCD. Sickle cell hepatopathy (SCH) is an all-inclusive term to describe the acute and chronic liver manifestations of SCD. The pathophysiology of SCH follows no defined pattern or sequence that poses challenges to clinicians and researchers alike. Evidence is lacking for this underreported disease at various levels from diagnostic to therapeutic options. This paper reviews the basic pathophysiology, clinical features, biochemical and radiological findings of various SCH manifestations and outlines the management of each condition. Old and new therapy options in SCD including hydroxyurea, red blood cell exchange transfusion, ursodeoxycholic acid, voxelotor, l-glutamine and crizanlizumab have been reviewed to investigate the role of these options in treating SCH. The role of liver transplant, haematopoietic stem cell transplant and gene therapy in SCH patients have been reviewed.

15.
J Econ Entomol ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001690

RESUMO

The clover seed weevil, Tychius picirostris Fabricius (Coleoptera: Curculionidae), is a major pest in Oregon white clover seed crops. Reliance on synthetic pyrethroid insecticides and limited availability of diverse modes of action (MoAs) has increased insecticide resistance selection in regional T. picirostris populations, emphasizing the need to evaluate novel chemistries and rotational strategies for effective insecticide resistance management (IRM). The efficacy of 8 foliar insecticide formulations for managing T. picirostris adult and larval life stages was determined in small and large-plot field trials across 2 crop years. In both years, bifenthrin (Brigade 2EC), the grower's standard, showed negligible adult and larval suppression. Insecticide formulations with isocycloseram and cyantraniliprole active ingredients reduced adult and larval populations when applied at BBCH 59-60 (prebloom) and BBCH 65-66 (full bloom) growth stages, respectively. While differences in T. picirostris abundance were observed among insecticide treatments, seed yield differences were not detected in large-plot trials. Larval abundance was correlated with reduced seed yield, and an economic threshold of ≥3 larvae per 30 inflorescences was determined as a conservative larval threshold to justify foliar applications of diamide insecticides. Additional commercial white clover seed fields were surveyed to compare larval scouting techniques, including a standard Berlese funnel and a grower's do-it-yourself funnel. Both larval extraction techniques were correlated and provided similar estimates of larval abundance. These findings demonstrate new MoAs, optimal insecticide application timing, and larval monitoring methods that can be incorporated into an effective T. picirostris IRM program in white clover seed crops.

16.
Bull World Health Organ ; 102(7): 476-485C, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38933479

RESUMO

Objective: To assess the availability of information on indicators of the World Health Organization and United Nations Children's Fund primary health-care measurement framework in Bangladesh, India, Nepal, Pakistan and Sri Lanka and to outline the opportunities for and challenges to using the framework in these countries. Methods: We reviewed global and national data repositories for quantitative indicators of the framework and conducted a desk review of country documents for qualitative indicators in February-April 2023. We assessed data sources and cross-sectional survey tools to suggest possible sources of information on framework indicators that were not currently reported in the countries. We also identified specific indicators outside the framework on which information is collected in the countries and which could be used to measure primary health-care performance. Findings: Data on 54% (32/59) of the quantitative indicators were partially or completely available for the countries, ranging from 41% (24/59) in Pakistan to 64% (38/59) in Nepal. Information on 41% (66/163) of the qualitative subindicators could be acquired through desk reviews of country-specific documents. Information on input indicators was more readily available than on process and output indicators. The feasibility of acquiring information on the unreported indicators was moderate to high through adaptation of data collection instruments. Conclusion: The primary health-care measurement framework provides a platform to readily assess and track the performance of primary health care. Countries should improve the completeness, quality and use of existing data for strengthening of primary health care.


Assuntos
Atenção Primária à Saúde , Nações Unidas , Organização Mundial da Saúde , Humanos , Atenção Primária à Saúde/organização & administração , Nepal , Bangladesh , Paquistão , Índia , Estudos Transversais , Sri Lanka , Indicadores de Qualidade em Assistência à Saúde
17.
Langmuir ; 40(25): 12911-12924, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38691550

RESUMO

Multifunctional carbon-based materials exhibit a large number of unprecedented active sites via an electron transfer process and act as a desired platform for exploring high-performance electroactive material. Herein, we exemplify the holistic design of a heterometallic nanostructured material (MWCNTs@KR-6/Mn/Sn/Pb) formed by the integration of metals (Mn2+, Sn2+, and Pb2+) and a dipodal ligand (KR-6) at the surface of multiwalled carbon nanotubes (MWCNTs). First, MWCNTs@KR-6 was readily synthesized via a noncovalent approach, which was further sequentially doped by Mn2+, Sn2+, and Pb2+ to give MWCNTs@KR-6/Mn/Sn/Pb. The designed material showed excellent electrochemical activity for the discrimination of insecticides belonging to structurally different classes. In contrast to that of the individual building components, both the stability and electrochemical activity of heterometallic nanostructured material were remarkably enhanced, resulting in a magnificent electrochemical performance of the developed material. Hence, the current work reports a comprehensive synthetic approach for MWCNTs@KR-6/Mn/Sn/Pb synthesis by synergizing unique properties of the heterometallic complex with MWCNTs. This work also offers a new insight into the design of multifunctional carbon-based materials for discrimination of different analytes on the basis of their redox potential.

18.
Chemistry ; 30(45): e202401239, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38818941

RESUMO

Herein, we describe water-soluble heteroaryl azopyridinium ionic photoswitches (HAPIPs). We aim to combine variations in five-membered heterocycles, their substitutions, N-alkyl groups at pyridinium nitrogen, the position of pyridinium center relative to azo group, counterions, and solvents, in achieving better photoswitching. Through these studies, we successfully tuned the half-life of Z isomers of the resultant HAPIPs between seconds to days in water. Extensive spectroscopic studies and density functional theory (DFT) computations unravelled the factors responsible for thermal relaxation behavior. Considering the versatility of these photoswitches, the tunability of half-lives and photoswitching in aqueous medium allows the scope of applications in several fields.

19.
J Exp Bot ; 75(10): 2773-2775, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764322
20.
ACS Appl Bio Mater ; 7(6): 4162-4174, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38769764

RESUMO

The escalating threat of antimicrobial resistance has become a global health crisis. Therefore, there is a rising momentum in developing biomaterials with self-sanitizing capabilities and inherent antibacterial properties. Despite their promising antimicrobial properties, metal nanoparticles (MNPs) have several disadvantages, including increased toxicity as the particle size decreases, leading to oxidative stress and DNA damage that need consideration. One solution is surface functionalization with biocompatible organic ligands, which can improve nanoparticle dispersibility, reduce aggregation, and enable targeted delivery to microbial cells. The existing research predominantly concentrates on the advancement of peptide-based hydrogels for coating materials to prevent bacterial infection, with limited exploration of developing surface coatings using organogels. Herein, we have synthesized organogel-based coatings doped with MNPs that can offer superior hydrophobicity, oleophobicity, and high stability that are not easily achievable with hydrogels. The self-assembled gels displayed distinct morphologies, as revealed by scanning electron microscopy and atomic force microscopy. The cross-linked matrix helps in the controlled and sustained release of MNPs at the site of bacterial infection. The synthesized self-assembled gel@MNPs exhibited excellent antibacterial properties against harmful bacteria such as Escherichia coli and Staphylococcus aureus and reduced bacterial viability up to 95% within 4 h. Cytotoxicity testing against metazoan cells demonstrated that the gels doped with MNPs were nontoxic (IC50 > 100 µM) to mammalian cells. Furthermore, in this study, we coated the organogel@MNPs on cotton fabric and tested it against Gram +ve and Gram -ve bacteria. Additionally, the developed cotton fabric exhibited superhydrophobic properties and developed a barrier that limits the interaction between bacteria and the surface, making it difficult for bacteria to adhere and colonize, which holds potential as a valuable resource for self-cleaning coatings.


Assuntos
Antibacterianos , Cobre , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Prata , Propriedades de Superfície , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Nanopartículas Metálicas/química , Prata/química , Prata/farmacologia , Cobre/química , Cobre/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Géis/química
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