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Giant exoplanets orbiting close to their host stars are unlikely to have formed in their present configurations1. These 'hot Jupiter' planets are instead thought to have migrated inward from beyond the ice line and several viable migration channels have been proposed, including eccentricity excitation through angular-momentum exchange with a third body followed by tidally driven orbital circularization2,3. The discovery of the extremely eccentric (e = 0.93) giant exoplanet HD 80606 b (ref. 4) provided observational evidence that hot Jupiters may have formed through this high-eccentricity tidal-migration pathway5. However, no similar hot-Jupiter progenitors have been found and simulations predict that one factor affecting the efficacy of this mechanism is exoplanet mass, as low-mass planets are more likely to be tidally disrupted during periastron passage6-8. Here we present spectroscopic and photometric observations of TIC 241249530 b, a high-mass, transiting warm Jupiter with an extreme orbital eccentricity of e = 0.94. The orbit of TIC 241249530 b is consistent with a history of eccentricity oscillations and a future tidal circularization trajectory. Our analysis of the mass and eccentricity distributions of the transiting-warm-Jupiter population further reveals a correlation between high mass and high eccentricity.
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An effective strategy was employed for the rapid development of a supramolecular metallohydrogel of Mg(II) ion (i.e., Mg@PEHA) using pentaethylenehexamine (PEHA) as a low-molecular-weight gelator in aqueous medium under ambient conditions. The mechanical stability of the synthesized Mg@PEHA metallohydrogel was characterized by using rheological analysis, which showed its robustness across different angular frequencies and oscillator stress levels. The metallohydrogel exhibited excellent thixotropic behavior, which signifies that Mg@PEHA has a self-healing nature. Field emission scanning electron microscopy and transmission electron microscopy images were utilized to explore the rectangular pebble-like hierarchical network of the Mg@PEHA metallohydrogel. Elemental mapping through energy-dispersive X-ray spectroscopy analysis confirmed the presence of primary chemical constituents in the metallohydrogel. Fourier transform infrared spectroscopy spectroscopy provided insights into the possible formation strategy of the metallohydrogel. In this work, Schottky diode structures in a metal-semiconductor-metal geometry based on a magnesium(II) metallohydrogel (Mg@PEHA) were constructed, and the charge transport behavior was observed. Additionally, a resistive random access memory (RRAM) device was developed using Mg@PEHA, which displayed bipolar resistive switching behavior at room temperature. The researchers investigated the switching mechanism, which involved the formation or rupture of conduction filaments, to gain insights into the resistive switching process. The RRAM device demonstrated excellent performance with a high ON/OFF ratio of approximately 100 and remarkable endurance of over 5000 switching cycles. RRAM devices exhibit good endurance, meaning they can endure a large number of read and write cycles without significant degradation in performance. RRAM devices have shown promising reliability in terms of long-term performance and stability, making them suitable for critical applications that require reliable memory solutions. Significant inhibitory activity against the drug-resistant Klebsiella pneumonia strain and its biofilm formation ability was demonstrated by Mg@PEHA. The minimum inhibitory concentration value of the metallohydrogel was determined to be 3 mg/mL when it was dissolved in 1% DMSO. To study the antibiofilm activity, an MTT assay was performed, revealing that biofilm inhibition (60%) commenced at 1 mg/mL of Mg@PEHA when dissolved in 1% DMSO. Moreover, in the mouse excisional wound model, Mg@PEHA played a crucial role in preventing postoperative wound infections and promoting wound healing.
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Rise in climate change-induced drought occurrences have amplified pollution of metal(loid)s, deteriorated soil quality, and deterred growth of crops. Rice straw-derived biochars (RSB) and cow manure-enriched biochars (CEB) were used in the investigation (at doses of 0%, 2.5%, 5%, and 7.5%) to ameliorate the negative impacts of drought, improve soil fertility, minimize arsenic pollution, replace agro-chemical application, and maximize crop yields. Even in soils exposed to severe droughts, 3 months of RSB and CEB amendment (at 7.5% dose) revealed decreased bulk density (13.7% and 8.9%), and increased cation exchange capacity (6.0% and 6.3%), anion exchange capacity (56.3% and 28.0%), porosity (12.3% and 7.9%), water holding capacity (37.5% and 12.5%), soil respiration (17.8% and 21.8%), and nutrient contents (especially N and P). Additionally, RSB and CEB decreased mobile (30.3% and 35.7%), bio-available (54.7% and 45.3%), and leachable (55.0% and 56.5%) fractions of arsenic. Further, pot experiments with Bengal gram and coriander plants showed enhanced growth (62-188% biomass and 90-277% length) and reduced arsenic accumulation (49-54%) in above ground parts of the plants. Therefore, biochar application was found to improve physico-chemical properties of soil, minimize arsenic contamination, and augment crop growth even in drought-stressed soils. The investigation suggests utilisation of cow manure for eco-friendly fabrication of nutrient-rich CEB, which could eventually promote sustainable agriculture and circular economy. With the increasing need for sustainable agricultural practices, the use of biochar could provide a long-term solution to enhance soil quality, mitigate the effects of climate change, and ensure food security for future generations. Future research should focus on optimizing biochar application across various soil types and climatic conditions, as well as assessing its long-term effectiveness.
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Arsênio , Carvão Vegetal , Secas , Poluentes do Solo , Solo , Carvão Vegetal/química , Arsênio/análise , Solo/química , Poluentes do Solo/análise , Esterco/análise , Oryza/crescimento & desenvolvimento , Desenvolvimento Vegetal/efeitos dos fármacos , BovinosRESUMO
Nanomaterial synthesis is a growing study area because of its extensive range of uses. Nanoparticles' high surface-to-volume ratio and rapid interaction with various particles make them appealing for diverse applications. Traditional physical and chemical methods for creating metal nanoparticles are becoming outdated because they involve complex manufacturing processes, high energy consumption, and the formation of harmful by-products that pose major dangers to human health and the environment. Therefore, there is an increasing need to find alternative, cost-effective, dependable, biocompatible, and environmentally acceptable ways of producing nanoparticles. The process of synthesizing nanoparticles using microbes has become highly intriguing because of their ability to create nanoparticles of varying sizes, shapes, and compositions, each with unique physicochemical properties. Microbes are commonly used in nanoparticle production because they are easy to work with, can use low-cost materials, such as agricultural waste, are cheap to scale up, and can adsorb and reduce metal ions into nanoparticles through metabolic activities. Biogenic synthesis of nanoparticles provides a clean, nontoxic, ecologically friendly, and sustainable method using renewable ingredients for reducing metals and stabilizing nanoparticles. Nanomaterials produced by bacteria can serve as an effective pollution control method due to their many functional groups that can effectively target contaminants for efficient bioremediation, aiding in environmental cleanup. At the end of the paper, we will discuss the obstacles that hinder the use of biosynthesized nanoparticles and microbial-based nanoparticles. The paper aims to explore the sustainability of microorganisms in the burgeoning field of green nanotechnology.
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In this study, we evaluated gamete quality parameters of mature male koi carp (Cyprinus carpio) exposed to three different concentrations (1, 10, and 100 µg/L) of di-(2-ethylhexyl) phthalate (DEHP). After 60 days of exposure, there was a significant decrease in the gonadosomatic index (GSI) of males exposed to 10 and 100 µg/L of DEHP. Histological analysis of the testes revealed impaired histoarchitecture, including inflammatory cells, intratubular vacuoles, and swollen seminiferous tubules in treatment groups. Gamete quality parameters like sperm production, motility, spermatocrit, and sperm density values were significantly decreased at the 10 and 100 µg/L concentrations. Biochemical compositions, including glucose, cholesterol, and total protein levels, were significantly changed in the treatment groups. Similarly, the ionic compositions of seminal fluid (Na, K, Ca, and Mg) also varied in the treatment groups. Furthermore, the 11-ketotestosterone levels were decreased, and the 17-ß estradiol levels were increased in the DEHP-treated groups. The mRNA expression levels of reproduction-related genes, including Fshr, Lhr, Ar, Erα, and Erß, were significantly changed in the DEHP-treated males in a dose-dependent manner. In conclusion, the findings of this study confirmed that environmentally relevant exposure to DEHP may contribute to a decline in the gamete quality of male fishes.
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Tropical fruits are defined as fruits that are grown in hot and humid regions within the Tropic of Cancer and Tropic of Capricorn, covering most of the tropical and subtropical areas of Asia, Africa, Central America, South America, the Caribbean and Oceania. Depending on the cultivation area covered, economic value and popularity these tropical fruits are divided into major and minor tropical fruits. There is an annual increment of 3.8% in terms of commercialization of the tropical fruits. In total 26 minor tropical fruits (Kiwifruit, Lutqua, Carambola, Tree Tomato, Elephant apple, Rambutan, Bay berry, Mangosteen, Bhawa, Loquat, Silver berry, Durian, Persimon, Longan, Passion fruit, Water apple, Pulasan, Indian gooseberry, Guava, Lychee, Annona, Pitaya, Sapodilla, Pepino, Jaboticaba, Jackfruit) have been covered in this work. The nutritional composition, phytochemical composition, health benefits, traditional use of these minor tropical fruits and their role in food fortification have been portrayed.
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Frutas , Malus , Frutas/química , Antioxidantes/análise , Alimento Funcional , Compostos Fitoquímicos/análiseRESUMO
Shigella flexneri is a gram-negative bacterial pathogen that causes dysentery. Critical for disease is the ability of Shigella to use an actin-based motility (ABM) process to spread between cells of the colonic epithelium. ABM transports bacteria to the periphery of host cells, allowing the formation of plasma membrane protrusions that mediate spread to adjacent cells. Here we demonstrate that efficient protrusion formation and cell-to-cell spread of Shigella involves bacterial stimulation of host polarized exocytosis. Using an exocytic probe, we found that exocytosis is locally upregulated in bacterial protrusions in a manner that depends on the Shigella type III secretion system. Experiments involving RNA interference (RNAi) indicate that efficient bacterial protrusion formation and spread require the exocyst, a mammalian multi-protein complex known to mediate polarized exocytosis. In addition, the exocyst component Exo70 and the exocyst regulator RalA were recruited to Shigella protrusions, suggesting that bacteria manipulate exocyst function. Importantly, RNAi-mediated depletion of exocyst proteins or RalA reduced the frequency of protrusion formation and also the lengths of protrusions, demonstrating that the exocyst controls both the initiation and elongation of protrusions. Collectively, our results reveal that Shigella co-opts the exocyst complex to disseminate efficiently in host cell monolayers.
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Extensões da Superfície Celular/metabolismo , Disenteria Bacilar/microbiologia , Exocitose , Shigella flexneri/fisiologia , Sistemas de Secreção Tipo III/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas ral de Ligação ao GTP/metabolismo , Actinas/metabolismo , Proteínas de Bactérias/metabolismo , Células CACO-2 , Extensões da Superfície Celular/microbiologia , Células HeLa , Interações Hospedeiro-Patógeno , Humanos , Interferência de RNARESUMO
A panchromatic triad and a charge-separation unit are joined in a crossbar architecture to capture solar energy. The panchromatic-absorber triad (T) is comprised of a central free-base porphyrin that is strongly coupled via direct ethyne linkages to two perylene-monoimide (PMI) groups. The charge-separation unit incorporates a free-base or zinc chlorin (C or ZnC) as a hole acceptor (or electron donor) and a perylene-diimide (PDI) as an electron acceptor, both attached to the porphyrin via diphenylethyne linkers. The free-base porphyrin is common to both light-harvesting and charge-separation motifs. The chlorin and PDI also function as ancillary light absorbers, complementing direct excitation of the panchromatic triad to produce the discrete lowest excited state of the array (T*). Attainment of full charge separation across the pentad entails two steps: (1) an initial excited-state hole/electron-transfer process to oxidize the chlorin (and reduce the panchromatic triad) or reduce the PDI (and oxidize the panchromatic triad); and (2) subsequent ground-state electron/hole migration to produce oxidized chlorin and reduced PDI. Full charge separation for pentad ZnC-T-PDI to generate ZnC+-T-PDI- occurs with a quantum yield of â¼30% and mean lifetime â¼1 µs in dimethyl sulfoxide. For C-T-PDI, initial charge separation is followed by rapid charge recombination. The molecular designs and studies reported here reveal the challenges of balancing the demands for charge separation (linker length and composition, excited-state energies, redox potentials, and medium polarity) with the constraints for panchromatic absorption (strong electronic coupling of the porphyrin and two PMI units) for integrated function in solar-energy conversion.
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Perileno , Porfirinas , Transporte de Elétrons , ImidasRESUMO
Electronic interactions between tetrapyrroles are utilized in natural photosynthetic systems to tune the light-harvesting and energy-/charge-transfer processes in these assemblies. Such interactions also can be employed to tailor the electronic properties of tetrapyrrolic dyads and larger arrays for use in materials science and biomedical research. Here, we have utilized static and time-resolved optical spectroscopy to characterize the optical absorption and emission properties of a set of chlorin and bacteriochlorin dyads with varying degrees of through-bond (TB) and through-space (TS) interactions between the constituent macrocycles. The dyads consist of two chlorins or two bacteriochlorins joined by a linker that utilizes a triple-double-triple-bond (enediyne) motif in which the double-bond portion is an ester-substituted ethylene or o-phenylene unit. The photophysical studies are coupled with density functional theory (DFT) calculations to probe the ground-state molecular orbital (MO) characteristics of the dyads and time-dependent DFT calculations (TDDFT) to elucidate excited-state properties. The latter include electronic characteristics of the singlet excited-state manifold and the absorption transitions to these states from the electronic ground state. A comparison of the MO and calculated spectral properties of each dyad with the linker present versus disrupted (by eliminating the double-bond portion) gives insight into the relative contributions of TB versus TS interactions to the electronic properties of the dyads. The results show that the TB and TS contributions are additive (constructively interfere), which is not always the case for molecular dyads. Most of the dyads have shorter lifetimes of the lowest singlet excited state compared to the parent monomer, which derives from increased S1 â S0 internal conversion. The enhancement is greater for the dyads in benzonitrile than in toluene. The studies provide insights into the nature of the electronic interactions between the constituents in the tetrapyrrole arrays and how these interactions dictate the spectral properties and excited-state decay characteristics.
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Fotossíntese , Tetrapirróis , Eletrônica , Transferência de Energia , Análise Espectral , Tetrapirróis/químicaRESUMO
Medicinal plants have considerable potential as antimicrobial agents due to the presence of secondary metabolites. This comprehensive overview aims to summarize the classification, morphology, and ethnobotanical uses of Euphorbia neriifolia L. and its derived phytochemicals with the recent updates on the pharmacological properties against emerging infectious diseases, mainly focusing on bacterial, viral, fungal, and parasitic infections. The data were collected from electronic databases, including Google Scholar, PubMed, Semantic Scholar, ScienceDirect, and SpringerLink by utilizing several keywords like 'Euphorbia neriifolia', 'phytoconstituents', 'traditional uses', 'ethnopharmacological uses', 'infectious diseases', 'molecular mechanisms', 'COVID-19', 'bacterial infection', 'viral infection', etc. The results related to the antimicrobial actions of these plant extracts and their derived phytochemicals were carefully reviewed and summarized. Euphol, monohydroxy triterpene, nerifoliol, taraxerol, ß-amyrin, glut-5-(10)-en-1-one, neriifolione, and cycloartenol are the leading secondary metabolites reported in phytochemical investigations. These chemicals have been shown to possess a wide spectrum of biological functions. Different extracts of E. neriifolia exerted antimicrobial activities against various pathogens to different extents. Moreover, major phytoconstituents present in this plant, such as quercetin, rutin, friedelin, taraxerol, epitaraxerol, taraxeryl acetate, 3ß-friedelanol, 3ß-acetoxy friedelane, 3ß-simiarenol, afzelin, 24-methylene cycloarenol, ingenol triacetate, and ß-amyrin, showed significant antimicrobial activities against various pathogens that are responsible for emerging infectious diseases. This plant and the phytoconstituents, such as flavonoids, monoterpenoids, diterpenoids, triterpenoids, and alkaloids, have been found to have significant antimicrobial properties. The current evidence suggests that they might be used as leads in the development of more effective drugs to treat emerging infectious diseases, including the 2019 coronavirus disease (COVID-19).
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Tratamento Farmacológico da COVID-19 , Doenças Transmissíveis Emergentes , Euphorbia , Doenças Transmissíveis Emergentes/tratamento farmacológico , Etnobotânica , Etnofarmacologia , Humanos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Fitoterapia , Extratos Vegetais/farmacologiaRESUMO
Wendlandia tinctoria var. grandis (Roxb.) DC. (Family: Rubiaceae) is a semi-evergreen shrub distributed over tropical and subtropical Asia. The present research intended to explore the pharmacological potential of the stem extract of W. tinctoria, focusing on the antioxidant, hypoglycemic, and antidiarrheal properties, and to isolate various secondary metabolites as mediators of such activities. A total of eight phenolic compounds were isolated from the dichloromethane soluble fraction of the stem extract of this plant, which were characterized by electrospray ionization (ESI) mass spectrometric and 1H NMR spectroscopic data as liquiritigenin (1), naringenin (2), apigenin (3), kaempferol (4), glabridin (5), ferulic acid (6), 4-hydroxybenzoic acid (7), and 4-hydroxybenzaldehyde (8). The dichloromethane soluble fraction exhibited the highest phenolic content (289.87 ± 0.47 mg of GAE/g of dried extract) and the highest scavenging activity (IC50 = 18.83 ± 0.07 µg/mL) against the DPPH free radical. All of the isolated compounds, except 4-hydroxybenzaldehyde, exerted a higher antioxidant effect (IC50 = 6.20 ± 0.10 to 16.11 ± 0.02 µg/mL) than the standard butylated hydroxytoluene (BHT) (IC50 = 17.09 ± 0.01 µg/mL). Significant hypoglycemic and antidiarrheal activities of the methanolic crude extract at both doses (200 mg/kg bw and 400 mg/kg bw) were observed in a time-dependent manner. Furthermore, the computational modeling study supported the current in vitro and in vivo findings, and the isolated constituents had a higher or comparable binding affinity for glutathione reductase and urase oxidase enzymes, glucose transporter 3 (GLUT 3), and kappa-opioid receptor, inferring potential antioxidant, hypoglycemic, and antidiarrheal properties, respectively. This is the first report of all of these phenolic compounds being isolated from this plant species and even the first demonstration of the plant stem extract's antioxidant, hypoglycemic, and antidiarrheal potentials. According to the current findings, the W. tinctoria stem could be a potential natural remedy for treating oxidative stress, hyperglycemia, and diarrhea. Nevertheless, further extensive investigation is crucial for thorough phytochemical screening and determining the precise mechanisms of action of the plant-derived bioactive metabolites against broad-spectrum molecular targets.
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Hiperglicemia , Rubiaceae , Antidiarreicos , Antioxidantes/química , Apigenina , Benzaldeídos , Hidroxitolueno Butilado , Diarreia , Radicais Livres , Proteínas Facilitadoras de Transporte de Glucose , Glutationa Redutase , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/farmacologia , Quempferóis , Cloreto de Metileno , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Receptores OpioidesRESUMO
Coronopus didymus (Brassicaceae) commonly known as lesser swine cress has been reported to be used for its pharmacological activities. This study aimed to evaluate the medicinal potential of C. didymus extracts against cancer, diabetes, infectious bacteria and oxidative stress and the identification of bioactive compounds present in these extracts. The effects of using different solvents for the extraction of C. didymus on the contents of major polyphenols and biological activities were investigated. Plant sample was shade dried, ground to a fine powder, and then soaked in pure acetone, ethanol and methanol. The highest contents of major polyphenols were found in methanol-based extract, i.e., chlorogenic acid, HB acid, kaempferol, ferulic acid, quercetin and benzoic acid with 305.02, 12.42, 11.5, 23.33, 975.7 and 428 mg/g of dry weight, respectively, followed by ethanol- and acetone-based extracts. The methanol-based extract also resulted in the highest antioxidant activities (56.76%), whereas the highest antiproliferative (76.36) and alpha glucosidase inhabitation (96.65) were demonstrated in ethanol-based extracts. No antibacterial property of C. didymus was observed against all the tested strains of bacteria. Further studies should be focused on the identification of specific bioactive compounds responsible for pharmacological activities.
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Brassicaceae , Lepidium , Acetona , Animais , Antioxidantes/farmacologia , Ácido Benzoico , Ácido Clorogênico , Etanol , Hipoglicemiantes/farmacologia , Quempferóis , Metanol , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Pós , Quercetina , Solventes , Suínos , alfa-GlucosidasesRESUMO
In the current decade, nanoparticles are synthesized using solvents that are environmentally friendly. A number of nanoparticles have been synthesized at room temperature using water as a solvent, such as gold (Au) and silver (Ag) nanoparticles. As part of nanotechnology, nanoparticles are synthesized through biological processes. Biological methods are the preferred method for the synthesis of inorganic nanoparticles (AgNPs) as a result of their simple and non-hazardous nature. Nanoparticles of silver are used in a variety of applications, including catalysts, spectrally selective coatings for solar absorption, optical objectives, pharmaceutical constituents, and chemical and biological sensing. Antimicrobial agents are among the top uses of silver nanoparticles. In the current study, silver nanoparticles were biologically manufactured through Madhuca longifolia, and their antibacterial activity against pathogenic microorganisms, anticancer, anti-inflammatory, and antioxidant activities were assessed. UV-Vis spectroscopy, XRD (X-ray diffraction), transmission electron microscopy, Zeta Potential, and FTIR were used to characterize silver nanoparticles. The current work describes a cheap and environmentally friendly method to synthesize silver nanoparticles from silver nitrate solution by using plant crude extract as a reducing agent.
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Anti-Infecciosos , Madhuca , Nanopartículas Metálicas , Antibacterianos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Ouro/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Substâncias Redutoras , Prata/farmacologia , Nitrato de Prata , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Difração de Raios XRESUMO
Heterocyclic compounds containing nitrogen and sulfur, especially those in the thiazole family, have generated special interest in terms of their synthetic chemistry, which is attributable to their ubiquitous existence in pharmacologically dynamic natural products and also as overwhelmingly powerful agrochemicals and pharmaceuticals. The thiazolidin-2,4-dione (TZD) moiety plays a central role in the biological functioning of several essential molecules. The availability of substitutions at the third and fifth positions of the Thiazolidin-2,4-dione (TZD) scaffold makes it a highly utilized and versatile moiety that exhibits a wide range of biological activities. TZD analogues exhibit their hypoglycemic activity by improving insulin resistance through PPAR-γ receptor activation, their antimicrobial action by inhibiting cytoplasmic Mur ligases, and their antioxidant action by scavenging reactive oxygen species (ROS). In this manuscript, an effort has been made to review the research on TZD derivatives as potential antimicrobial, antioxidant, and antihyperglycemic agents from the period from 2010 to the present date, along with their molecular mechanisms and the information on patents granted to TZD analogues.
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Anti-Infecciosos , Produtos Biológicos , Compostos Heterocíclicos , Tiazolidinedionas , Agroquímicos , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Ligases , Nitrogênio , PPAR gama , Preparações Farmacêuticas , Espécies Reativas de Oxigênio , Enxofre , Tiazóis , Tiazolidinedionas/químicaRESUMO
Street dust samples were collected from industrial and commercial cities (Jamshedpur and Ranchi during monsoon and post-monsoon seasons) for detecting the levels of Cr, Cd, Cu, Ni, Pb, Zn, As, Co, Al, and Mn. The industrial city recorded higher metal concentrations compared to commercial. Similar trend of pseudo-total metal concentrations was observed in both the seasons at industrial city (Al > Mn > Zn > Cr > Pb > Cu > Ni > Cd) and only monsoon season at commercial city (Al > Mn > Zn > Cu > Cr > Pb > Ni > Cd). Zn > Cd was the most bioaccessible metal throughout the cities (monsoon and post-monsoon). The geochemical parameters (Igeo, EF, CF) were highest for Cd and lowest for Ni (both cities for the two seasons). Pollution Load Indices (PLI zone) were highest during the post-monsoon season in the industrial city. The highest carcinogenic risk was posed by Cr ranging from 1.87E-05 to 4.80E-05, in both the cities through ingestion and inhalation pathways. Children were found at higher risks, while the bioaccessible fractions posed neither carcinogenic nor non-carcinogenic threats to the population. Principal component analysis and correlation analysis indicated the influence of vehicular and industrial emissions, especially steel industry and coal-based thermal power plants as the major source of metals in street-dust. The outcomes of this work will be useful in providing baseline information of pollution along with their consequent environmental and human health risks of Jharkhand state.
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Poeira , Metais Pesados , Criança , China , Cidades , Poeira/análise , Monitoramento Ambiental , Poluição Ambiental/análise , Humanos , Metais Pesados/análise , Medição de RiscoRESUMO
A unique facile process has been adopted for fast assembly of a poly(N-vinyl imidazole) cross-linked ß-cyclodextrin hydrogel through microwave-assisted free radical polymerization, using N,N'-methylenebis(acrylamide) cross-linker. The copolymer possesses positive surface charge, one of the characteristic properties of an ideal hemostatic hydrogel. The functionalized imidazole-based hydrogel demonstrates rapid, superior blood coagulation kinetics under in vitro and in vivo conditions. On application to a major renal arterial hemorrhagic model, this hydrogel shows better blood clotting kinetics, leading to complete hemostasis in as few as â¼144 ± 7 s. Additionally, 350 µL of whole blood was clotted instantly, in â¼35 s, and therefore, reinforcing its hemostatic potential. The hydrogel demonstrates excellent biocompatibility, when seeded with human dermal fibroblast cells, retaining the native property of its predecessor. In addition, the hydrogel presents excellent hemocompatibility when tested with whole blood with the highest hemolytic ratio of 1.07 ± 0.05%. Moreover, it also demonstrates potential as a carrier for sustained release of an anesthetic drug, lidocaine hydrochloride monohydrate (â¼83% in 24 h). The rapid hemostatic behavior of the hydrogel is coupled with its cytocompatibility and hemocompatibilty properties along with controlled drug release characteristics. These behaviors evidently demonstrate it to be an excellent alternative for a superior hemostatic material for severe hemorrhagic conditions.
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Hemostáticos , beta-Ciclodextrinas , Hemostasia , Hemostáticos/farmacologia , Humanos , Hidrogéis/farmacologia , Imidazóis/farmacologia , beta-Ciclodextrinas/farmacologiaRESUMO
Biochar was produced from wheat straw (Triticum aestivum), rice straw (Oryza sativa), and kitchen waste at varying pyrolysis temperatures (300°C-700 °C). The biochars were screened depending on their production and physicochemical properties for the adsorptive removal of arsenic (As). The morphological analysis by Field emission scanning electron microscope revealed a porous biochar surface. Spectroscopic characterization of biochars indicated the co-existence of minerals, carboxyl, carbonyl, amide, and hydroxyl groups, which implies the suitability of biochar to immobilize metal (loid)s from soils. Changes in peaks were observed in Fourier-transform infrared and X-ray diffraction images after As sorption indicating the involvement of chemisorption. The thermogravimetric analysis and a low H/C value derived from the CHNS analyzer confirmed the high stability of biochar. The BET analysis was used to estimate the surface areas of wheat straw (15.8 m2 g-1), rice straw (12.5 m2 g-1), and kitchen waste (2.57 m2 g-1) -derived biochars. Batch sorption studies were performed to optimize experimental parameters for maximum removal of As. Maximum removal of As was observed for wheat straw-derived biochar (pyrolyzed at 500 °C) at 8 mg L-1 initial concentration (IC), 7.5 % dose, 25 °C temperature, and 60 min contact time (83.7 ± 0.06 %); in rice straw-derived biochar (pyrolyzed at 500 °C) at 8 mg L-1 IC, 7.5 % dose, 25 °C temperature, 90 min contact time (83.6 ± 0.37 %); and in kitchen waste-derived biochar (pyrolyzed at 500 °C) at 8 mg L-1 IC, 5 % dose, 25 °C temperature, 60 min contact time (76.7 ± 0.16 %). The sorption model parameters suggested the possibility of chemisorption, physisorption, diffusion, and ion exchange for the removal of As. Therefore, it could be recommended to farmers that instead of disposing or burning straws and waste openly, they could adopt the process of charring to generate livelihood security and mitigation of geogenic contaminants from the soil/water dynamic systems.
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Arsênio , Oryza , Adsorção , Carvão Vegetal , Pirólise , SoloRESUMO
BACKGROUND: Cabozantinib is a multikinase inhibitor of MET, VEGFR, AXL, and RET, which also has an effect on the tumour immune microenvironment by decreasing regulatory T cells and myeloid-derived suppressor cells. In this study, we examined the activity of cabozantinib in patients with metastatic platinum-refractory urothelial carcinoma. METHODS: This study was an open-label, single-arm, three-cohort phase 2 trial done at the National Cancer Institute (Bethesda, MD, USA). Eligible patients were 18 years or older, had histologically confirmed urothelial carcinoma or rare genitourinary tract histologies, Karnofsky performance scale index of 60% or higher, and documented disease progression after at least one previous line of platinum-based chemotherapy (platinum-refractory). Cohort one included patients with metastatic urothelial carcinoma with measurable disease as defined by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Two additional cohorts that enrolled in parallel (patients with bone-only urothelial carcinoma metastases and patients with rare histologies of the genitourinary tract) were exploratory. Patients received cabozantinib 60 mg orally once daily in 28-day cycles until disease progression or unacceptable toxicity. The primary endpoint was investigator-assessed objective response rate by RECIST in cohort one. Response was assessed in all patients who met the eligibility criteria and who received at least 8 weeks of therapy. All patients who received at least one dose of cabozantinib were included in the safety analysis. This completed study is registered with ClinicalTrials.gov, NCT01688999. FINDINGS: Between Sept 28, 2012, and Oct, 20, 2015, 68 patients were enrolled on the study (49 in cohort one, six in cohort two, and 13 in cohort three). All patients received at least one dose of cabozantinib. The median follow-up was 61·2 months (IQR 53·8-70·0) for the 57 patients evaluable for response. In the 42 evaluable patients in cohort one, there was one complete response and seven partial responses (objective response rate 19%, 95% CI 9-34). The most common grade 3-4 adverse events were fatigue (six [9%] patients), hypertension (five [7%]), proteinuria (four [6%]), and hypophosphataemia (four [6%]). There were no treatment-related deaths. INTERPRETATION: Cabozantinib has single-agent clinical activity in patients with heavily pretreated, platinum-refractory metastatic urothelial carcinoma with measurable disease and bone metastases and is generally well tolerated. Cabozantinib has innate and adaptive immunomodulatory properties providing a rationale for combining cabozantinib with immunotherapeutic strategies. FUNDING: National Cancer Institute Intramural Program and the Cancer Therapy Evaluation Program.
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Anilidas/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Piridinas/uso terapêutico , Neoplasias Urológicas/tratamento farmacológico , Adulto , Idoso , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Platina/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
Panchromatic absorbers that have robust photophysical properties enable new designs for molecular-based light-harvesting systems. Herein, we report experimental and theoretical studies of the spectral, redox, and excited-state properties of a series of perylene-monoimide-ethyne-porphyrin arrays wherein the number of perylene-monoimide units is stepped from one to four. In the arrays, a profound shift of absorption intensity from the strong violet-blue (B y and B x) bands of typical porphyrins into the green, red, and near-infrared (Q x and Q y) regions stems from mixing of chromophore and tetrapyrrole molecular orbitals (MOs), which gives multiplets of MOs having electron density spread over the entire array. This reduces the extensive mixing between porphyrin excited-state configurations and the transition-dipole addition and subtraction that normally leads to intense B and weak Q bands. Reduced configurational mixing derives from moderate effects of the ethyne and perylene on the MO energies and a more substantial effect of electron-density delocalization to reduce the configuration-interaction energy. Quantitative oscillator-strength analysis shows that porphyrin intensity is also shifted into the perylene-like green-region absorption and that the ethyne linkers lend absorption intensity. The reduced porphyrin configurational mixing also endows the S1 state with bacteriochlorin-like properties, including a 1-5 ns lifetime.
RESUMO
Signaling driven by hepatocyte growth factor (HGF) and MET receptor facilitates conspicuous biological responses such as epithelial cell migration, 3-D morphogenesis, and survival. The dynamic migration and promotion of cell survival induced by MET activation are bases for invasion-metastasis and resistance, respectively, against targeted drugs in cancers. Recent studies indicated that MET in tumor-derived exosomes facilitates metastatic niche formation and metastasis in malignant melanoma. In lung cancer, gene amplification-induced MET activation and ligand-dependent MET activation in an autocrine/paracrine manner are causes for resistance to epidermal growth factor receptor tyrosine kinase inhibitors and anaplastic lymphoma kinase inhibitors. Hepatocyte growth factor secreted in the tumor microenvironment contributes to the innate and acquired resistance to RAF inhibitors. Changes in serum/plasma HGF, soluble MET (sMET), and phospho-MET have been confirmed to be associated with disease progression, metastasis, therapy response, and survival. Higher serum/plasma HGF levels are associated with therapy resistance and/or metastasis, while lower HGF levels are associated with progression-free survival and overall survival after treatment with targeted drugs in lung cancer, gastric cancer, colon cancer, and malignant melanoma. Urinary sMET levels in patients with bladder cancer are higher than those in patients without bladder cancer and associated with disease progression. Some of the multi-kinase inhibitors that target MET have received regulatory approval, whereas none of the selective HGF-MET inhibitors have shown efficacy in phase III clinical trials. Validation of the HGF-MET pathway as a critical driver in cancer development/progression and utilization of appropriate biomarkers are key to development and approval of HGF-MET inhibitors for clinical use.