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Solvatochromic studies in conjunction with NCQDs and analysis of material at different pH levels provide valuable insights about the process of metal ion sensing. Metal ion sensing holds significant importance in various fields like environment monitoring, biomedical diagnostics and various industrial purpose. The detection of metal ions by mixing the nitrogen-doped quantum dots (NCQDs) in the solvent at different pH levels for the analysis of the photoluminescence spectra is the unique property to achieve selective metal ion detection. In present study, the synthesis of NCQDs was performed by the use of flowers of Tecoma stans. The synthesis of NCQDs to best of our knowledge using flowers of Tecoma stans as natural carbon source via hydrothermal process has been done for the first time. The NCQDs exhibit absorption bands ranging from 190 to 450 nm, with the energy band gap varying from 3.55 to 5.42 eV when mixed with different solvent such as, 1-4 dioxane, acetone, acetonitrile, ethyl- acetate, ethanol, methanol and toluene. The fluorescence spectra exhibited highly intense range from approximately 390 to 680 nm across various solvents. XRD analysis further confirmed the crystalline nature of the particles with an average size of 6.96 nm. Different peak positions of the FTIR spectra support functional groups having C-H stretching, C = O (carbonyl) stretching, and C = C stretching vibrations. In the study a notable solvatochromic shift was observed, indicating sensitivity to change in solvent polarity. Additionally, the investigation of the ratio of ground to excited state dipole moment based on solvatochromic shift yielded a value of 3.30. This provide valuable information about optical and electronic properties of NCQDs. Overall, our study sheds light on the unique properties of NCQDs synthesized from Tecoma stans flowers and their potential applications in metal ion sensing, pH probing, and solvent polarity studies.
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A new type of heavy-metal free single-element nanomaterial, called sulfur quantum dots (SQDs), has gained significant attention due to its advantages over traditional semiconductor QDs for several biomedical and optoelectronic applications. A straightforward and rapid synthesis approach for preparing highly fluorescent SQDs is needed to utilize this nanomaterial for technological applications. Until now, only a few synthesis approaches have been reported; however, these approaches are associated with long reaction times and low quantum yields (QY). Herein, we propose a novel optimized strategy to synthesize SQDs using a mix of probe sonication and heating, which reduces the reaction time usually needed from 125 h to a mere 15 min. The investigation employs cavitation and vibration effects of high energy acoustic waves to break down the bulk sulfur into nano-sized particles in the presence of highly alkaline medium and oleic acid. In contrast to previous reports, the obtained SQDs exhibited excellent aqueous solubility, desirable photostability, and a relatively high photoluminescence QY up to 10.4% without the need of any post-treatment. Additionally, the as-synthesized SQDs show excitation-dependent emission and excellent stability in different pH (2-12) and temperature (20 °C-80 °C) environments. Hence, this strategy opens a new pathway for rapid synthesis of SQDs and may facilitate the use of these materials for biomedical and optoelectronic applications.
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Aspergillus fumigatus is an opportunistic pathogen that primarily affects the lungs and frequently elicits an allergic immune response in human hosts via inhalation of its airborne asexual spores (conidia). In immunocompromised individuals, the conidia of this fungus can germinate in the lung and result in severe systemic infections characterised by widespread tissue and organ damage. Conversely, in healthy hosts, the innate immune system is instrumental in eliminating the conidia and preventing disease progression. As with numerous other pathogenic fungi, A. fumigatus possesses a set of virulence factors that facilitate its infective mechanism and the circumvention of immune defences in susceptible hosts. The intrinsic capacity of A. fumigatus to form complex 3D-structured biofilms, both on biotic and abiotic surfaces, represents a key determinant of its evasion of the host immune system and resistance to antifungal drugs. This review delineates the pivotal role of A. fumigatus biofilm structure and function as a significant virulence factor in pathogenic infections, such as aspergilloma and invasive pulmonary aspergillosis (IPA). Additionally, we discuss the importance for the development of novel antifungal drugs as drug-resistant strains continue to evolve. Furthermore, co-infections of A. fumigatus with other nosocomial pathogens have a substantial impact on patient's health outcomes. In this context, we provide a brief overview of COVID-19-associated pulmonary aspergillosis (CAPA), a recently documented condition that has gained attention due to its associated high degree of severity.
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Aspergilose , COVID-19 , Aspergilose Pulmonar , Humanos , Aspergillus fumigatus , Aspergilose/microbiologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Virulência , Fatores de Virulência , Imunidade , BiofilmesRESUMO
The use of microbial bioinoculants for managing plant diseases and promoting plant growth is an effective alternative approach to integrated farming. One of the devastating phytopathogens is Macrophomina phaseolina (Tassi) Goid. It is an omnipresent fungus infecting more than 500 plant species. It causes charcoal rot disease in soybean leading to 30-50% yield loss. Soybean Glycine max (L.) oil seed crop produced globally is highly susceptible to M. phaseolina. India is the fifth largest producer of soybean in the world. Madhya Pradesh is the largest soybean-producing state in India; Around 70% yield loss of soybean is accounted to M. phaseolina infection in India. Control of charcoal rot is the requisite of the current situation. Chemical control is not feasible due to saprophytic nature and prolonged survival of Macrophomina phaseolina. Chemical fungicides are expensive, toxic, hazardous, and cause pollution. Biological control is an effective approach to control this devastating fungus. The rhizosphere of soil is rich in beneficial microflora competent to suppress plant pathogens and also promote plant growth. PGPR have well-developed mechanisms that impart antagonistic traits to them. PGPR produces various antifungal metabolites siderophores and HCN which inhibit fungal growth, and can be used as potent BCA. Pseudomonas and Bacillus species have been reported effective against M. phaseolina. The mechanisms and antifungal compounds produced by these bacteria to control charcoal rot can be studied extensively. BCA or the metabolites secreted by them have the potential to develop effective bioformulations for soybean at the commercial level for sustainable agriculture.
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Ascomicetos/fisiologia , Glycine max/microbiologia , Interações Microbianas , Controle Biológico de Vetores , Doenças das Plantas/prevenção & controle , Rizosfera , Índia , Doenças das Plantas/microbiologia , Óleo de SojaRESUMO
Plants absorb sulphate, the oxidized form of elemental sulphur (S°), from soil. Sulphur-oxidizing bacteria play a key role in transformation of sulphur in soil. Oil seed crops require high amount of sulphur and it plays an important role in the formation of proteins, vitamins and enzymes. It increases yield, oil content and protein content in oil seed crops. Sulphur is the important constituent of amino acids, viz. methionine, cystine, and cysteine. It necessitates various enzymatic, metabolic processes such as photosynthesis and nitrogen fixation. In the last few years, the prominence of sulphur in oil seed crop nutrition has been accepted as widespread occurrence of its inadequacy in agricultural soil. Approximately 41% of Indian soil is deficient in sulphur. The soil microbial population is the major enforcement behind sulphur transformation. They mineralize, immobilize, oxidize and reduce the elemental and other reduced forms of sulphur. The main step in transformation is oxidation carried out by microorganisms to convert sulphur into sulphate. The chemolithotrophic bacteria belonging to genus Thiobacillus are of primary importance; there are heterotrophic bacteria also which can oxidize sulphur in soil. The pH reduction at the time of oxidation helps in mineralization and absorption of other essential nutrients also. This property of sulphur-oxidizing bacteria (SOB) shows their potential to be used as bioinoculants. Bioformulations prepared using carrier-based formulations, immobilization, biostimulation, etc., are sustainable forms of fertilizers. These SOB inoculants can be used to increase the fertility and sulphate production in soil.
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Bactérias/metabolismo , Produtos Agrícolas/microbiologia , Microbiologia do Solo , Solo/química , Enxofre/metabolismo , Inoculantes Agrícolas/metabolismo , Bactérias/classificação , Fertilizantes , Oxirredução , Sementes/metabolismo , Sulfatos/metabolismoRESUMO
Radiation frost events, which have become more common in the Mediterranean Basin in recent years, inflict extensive damage to tropical/subtropical fruit crops. During radiation frost, sub-zero temperatures are encountered in the dark, followed by high light during the subsequent clear-sky day. One of the key processes affected by these conditions is photosynthesis, which, when significantly inhibited, leads to the enhanced accumulation of reactive oxygen species (ROS) and damage. The use of 'chemical priming' treatments that induce plants' endogenous stress responses is a possible strategy to improve their coping with stress conditions. Herein, we studied the effects of priming with sodium hydrosulfide (NaHS), a donor of hydrogen sulfide (H2 S), on the response of photosynthesis to overnight frost and day high-light conditions in 'Hass' avocado (Persea americana Mill). We found that priming with a single foliar application of NaHS had positive effects on the response of grafted 'Hass' plants. Primed plants exhibited significantly reduced inhibition of CO2 assimilation, a lower accumulation of hydrogen peroxide as well as lower photoinhibition, as compared to untreated plants. The ability to maintain a high CO2 assimilation capacity after the frost was attained on the background of considerable inhibition in stomatal conductance. Thus, it was likely related to the lower accumulation of ROS and photodamage observed in primed 'Hass' plants. This work contributes toward the understanding of the response of photosynthesis in a subtropical crop species to frost conditions and provides a prospect for chemical priming as a potential practice in orchards during cold winters.
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Temperatura Baixa , Persea/fisiologia , Fotossíntese , Sulfetos/farmacologia , Frutas , Luz , Persea/efeitos dos fármacosRESUMO
The concurrence of microorganisms in niches that are hostile like extremes of temperature, pH, salt concentration and high pressure depends upon novel molecular mechanisms to enhance the stability of their proteins, nucleic acids, lipids and cell membranes. The structural, physiological and genomic features of extremophiles that make them capable of withstanding extremely selective environmental conditions are particularly fascinating. Highly stable enzymes exhibiting several industrial and biotechnological properties are being isolated and purified from these extremophiles. Successful gene cloning of the purified extremozymes in the mesophilic hosts has already been done. Various extremozymes such as amylase, lipase, xylanase, cellulase and protease from thermophiles, halothermophiles and psychrophiles are of industrial interests due to their enhanced stability at forbidding conditions. In this review, we made an attempt to point out the unique features of extremophiles, particularly thermophiles and psychrophiles, at the structural, genomic and proteomic levels, which allow for functionality at harsh conditions focusing on the temperature tolerance by them.
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γ-Glutamylcyclotransferase initiates glutathione degradation to component amino acids l-glutamate, l-cysteine and l-glycine. The enzyme is encoded by three genes in Arabidopsis thaliana, one of which (GGCT2;1) is transcriptionally upregulated by starvation for the essential macronutrient sulfur (S). Regulation by S-starvation suggests that GGCT2;1 mobilizes l-cysteine from glutathione when there is insufficient sulfate for de novo l-cysteine synthesis. The response of wild-type seedlings to S-starvation was compared to ggct2;1 null mutants. S-starvation causes glutathione depletion in S-starved wild-type seedlings, but higher glutathione is maintained in the primary root tip than in other seedling tissues. Although GGCT2;1 is induced throughout seedlings, its expression is concentrated in the primary root tip where it activates the γ-glutamyl cycle. S-starved wild-type plants also produce longer primary roots, and lateral root growth is suppressed. While glutathione is also rapidly depleted in ggct2;1 null seedlings, much higher glutathione is maintained in the primary root tip compared to the wild-type. S-starved ggct2;1 primary roots grow longer than the wild-type, and lateral root growth is not suppressed. These results point to a role for GGCT2;1 in S-starvation-response changes to root system architecture through activity of the γ-glutamyl cycle in the primary root tip. l-Cysteine mobilization from glutathione is not solely a function of GGCT2;1.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Glutationa/metabolismo , Raízes de Plantas/metabolismo , Enxofre/deficiência , gama-Glutamilciclotransferase/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/genética , Butionina Sulfoximina/farmacologia , Cisteína/metabolismo , DNA Bacteriano/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Meristema/metabolismo , Modelos Biológicos , Mutação/genética , Fenótipo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , gama-Glutamilciclotransferase/genéticaRESUMO
The toxicity of azetidine-2-carboxylic acid (A2C), a structural analogue of L-proline, results from its incorporation into proteins due to misrecognition by prolyl-tRNA synthetase (ProRS). The growth of Arabidopsis thaliana seedling roots is more sensitive to inhibition by A2C than is cotyledon growth. Arabidopsis contains two ProRS isozymes. AtProRS-Org (At5g52520) is localized in chloroplasts/mitochondria, and AtProRS-Cyt (At3g62120) is cytosolic. AtProRS-Cyt mRNA is more highly expressed in roots than in cotyledons. Arabidopsis ProRS isoforms were expressed as His-tagged recombinant proteins in Escherichia coli. Both enzymes were functionally active in ATP-PPi exchange and aminoacylation assays, and showed similar Km for L-proline. A major difference was observed in the substrate specificity of the two enzymes. AtProRS-Cyt showed nearly identical substrate specificity for L-proline and A2C, but for AtProRS-Org the specificity constant was 77.6 times higher for L-proline than A2C, suggesting that A2C-sensitivity may result from lower amino acid specificity of AtProRS-Cyt. Molecular modelling and simulation results indicate that this specificity difference between the AtProRS isoforms may result from altered modes of substrate binding. Similar kinetic results were obtained with the ProRSs from Zea mays, suggesting that the difference in substrate specificity is a conserved feature of ProRS isoforms from plants that do not accumulate A2C and are sensitive to A2C toxicity. The discovery of the mode of action of A2C toxicity could lead to development of biorational weed management strategies.
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Aminoácidos/metabolismo , Aminoacil-tRNA Sintetases/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Ácido Azetidinocarboxílico/farmacologia , Aminoacil-tRNA Sintetases/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cotilédone/efeitos dos fármacos , Cotilédone/genética , Cotilédone/crescimento & desenvolvimento , Cotilédone/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Especificidade por Substrato , Zea mays/efeitos dos fármacos , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismoRESUMO
Positivity of microscopy and culture was greater (P < 0.0001) in men with urethral discharge syndrome (65.8%) than in women with vaginal/cervical discharge (0.5%), indicating that basic diagnostic tests may not be cost-effective for diagnosis of vaginal/cervical discharge syndrome. Microscopy when compared with culture showed sensitivity, specificity, positive predictive value and negative predictive value of 95.4%, 77.6%, 84.6%, and 95.3%, in men, whereas in women, it was 77.8%, 99.9%, 92.1%, and 99.9%, respectively.
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Gonorreia/diagnóstico , Neisseria gonorrhoeae/isolamento & purificação , Análise Custo-Benefício , Feminino , Gonorreia/microbiologia , Humanos , Índia , Masculino , Microscopia , Sensibilidade e Especificidade , Doenças Uretrais/diagnóstico , Doenças Uretrais/microbiologia , Vagina/microbiologia , Descarga Vaginal/diagnóstico , Descarga Vaginal/microbiologiaRESUMO
Antimicrobial susceptibility testing of 258 Neisseria gonorrhoeae isolates by Etest determined that 60.1% were multidrug resistant (MDR), while 5% of the strains had decreased susceptibility to currently recommended extended-spectrum cephalosporins (ESCs). Among these, 84.5% of MDR strains and 76.9% of strains that had decreased susceptibility to ESCs were susceptible to gentamicin. No MDR isolate was resistant to gentamicin. These in vitro results suggest that gentamicin might be an effective treatment option for the MDR strains and in dual therapy for gonorrhea. However, further research regarding the clinical treatment outcomes is essential.
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Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Gentamicinas/farmacologia , Neisseria gonorrhoeae/efeitos dos fármacos , Cefalosporinas/farmacologia , Feminino , Gonorreia/dietoterapia , Gonorreia/microbiologia , Humanos , Índia , Masculino , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/crescimento & desenvolvimento , Neisseria gonorrhoeae/isolamento & purificaçãoRESUMO
OBJECTIVES: XDR Neisseria gonorrhoeae imposes the threat of untreatable gonorrhoea. Gentamicin is considered for future treatment; however, no interpretation criteria for the CLSI and calibrated dichotomous sensitivity (CDS) disc diffusion (DD) techniques are available for N. gonorrhoeae. We investigated the in vitro gentamicin activity by MIC and DD methods, proposed DD breakpoints and determined DD ranges for 10 international quality control (QC) strains. METHODS: Gentamicin susceptibility of 333 N. gonorrhoeae isolates, including 323 clinical isolates and 10 QC strains, was determined. MIC determination (Etest) and DD methods (CLSI and CDS) were performed. The relationship between MIC, inhibition zone diameter and annular radius was determined by linear regression analysis and the correlation coefficient (r) was calculated. RESULTS: Gentamicin MICs for the QC strains were within published ranges. Of the 323 clinical isolates, according to published breakpoints 75.9%, 23.5% and 0.6% were susceptible, intermediately susceptible and resistant, respectively. Based on error minimization with MICs of ≤4, 8-16 and ≥32 mg/L, breakpoints proposed are susceptible ≥16 mm, intermediately susceptible 13-15 mm and resistant ≤12 mm for the CLSI method and susceptible ≥6 mm, less susceptible 3-5 mm and resistant ≤2 mm for the CDS technique. CONCLUSIONS: Low resistance to gentamicin was identified and gentamicin might be a future treatment option for gonorrhoea. Tentative gentamicin zone breakpoints were defined for two DD methods and QC ranges for 10 international reference strains were established. Our findings suggest that in resource-poor settings where MIC testing is not a feasible option, the DD methods can be used to indicate gentamicin resistance.
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Antibacterianos/farmacologia , Gentamicinas/farmacologia , Testes de Sensibilidade Microbiana/normas , Neisseria gonorrhoeae/efeitos dos fármacos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Uroporphyrinogen III methyl transferase (UPM1) and Sirohydrochlorin ferrochelatase (SIRB) are the important genes involved in the biosynthesis of siroheme, the prosthetic group of nitrite reductases (NiR) and sulfite reductases (SiR) involved in nitrogen and sulfur assimilation. Both UPM1 and SIRB could be potential candidate genes targeted for sustainable agriculture especially in N-deficient soil. The phylogenetic analysis revealed that these genes are highly conserved among algae, bryophytes and vascular plants including dicots and monocots. The Arabidopsis proteins UPM1 and SIRB have close similarity with Camelina sativa followed by Brassica napus, Brassica rapa, and Brassica oleracea of the family brassicaceae. The tissue specific expression studies revealed that both the gene are expressed in stem, flower and silique and have highest expression in leaves where the protein content is quite high. The in silico promoter analysis revealed the presence of several light-responsive elements like GATA box, G box, I box, SORLIP2, SORLIP5, SORLREP3 and SORLREP4. Therefore, expression of both the genes was minimal in etiolated seedlings and was upregulated in light. Photo-regulation of transcript abundance of UPM1 and SIRB involved in the biosynthesis of siroheme the cofactor involved in 6 electron reduction of NO2- and SO32- by NiR and SiR is crucial as the gene expression of latter two enzymes along with other N and S assimilatory enzymes are also modulated by light.
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Sulfur is required for the biosynthesis of cysteine, methionine and numerous other metabolites, and thus is critical for cellular metabolism and various growth and developmental processes. Plants are able to sense their physiological state with respect to sulfur availability, but the sensor remains to be identified. Here we report the isolation and characterization of two novel allelic mutants of Arabidopsis thaliana, sel1-15 and sel1-16, which show increased expression of a sulfur deficiency-activated gene ß-glucosidase 28 (BGLU28). The mutants, which represent two different missense alleles of SULTR1;2, which encodes a high-affinity sulfate transporter, are defective in sulfate transport and as a result have a lower cellular sulfate level. However, when treated with a very high dose of sulfate, sel1-15 and sel1-16 accumulated similar amounts of internal sulfate and its metabolite glutathione (GSH) to wild-type, but showed higher expression of BGLU28 and other sulfur deficiency-activated genes than wild-type. Reduced sensitivity to inhibition of gene expression was also observed in the sel1 mutants when fed with the sulfate metabolites Cys and GSH. In addition, a SULTR1;2 knockout allele also exhibits reduced inhibition in response to sulfate, Cys and GSH, consistent with the phenotype of sel1-15 and sel1-16. Taken together, the genetic evidence suggests that, in addition to its known function as a high-affinity sulfate transporter, SULTR1;2 may have a regulatory role in response to sulfur nutrient status. The possibility that SULTR1;2 may function as a sensor of sulfur status or a component of a sulfur sensory mechanism is discussed.
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Proteínas de Transporte de Ânions/genética , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Mutação , Enxofre/metabolismo , Sequência de Aminoácidos , Proteínas de Transporte de Ânions/química , Proteínas de Transporte de Ânions/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Cisteína/administração & dosagem , Glutationa/administração & dosagem , Dados de Sequência Molecular , Homologia de Sequência de AminoácidosRESUMO
Consuming hygienic and secure food has become challenging for everyone. The preservation of excess food without negatively affecting its nutritional values, shelf life, freshness, or effectiveness would undoubtedly strengthen the food industry. Nanotechnology is a new and intriguing technology that is currently being implemented in the food industry. Metal-based nanomaterials have considerable potential for use in packaging and food processing. These materials have many advanced physical and chemical characteristics. Since these materials are increasingly being used in food applications, there are certain negative health consequences related to their toxicity when swallowed through food. In this article, we have addressed the introduction and applications of metal/metal oxide nanoparticles (MNPs), food processing and food packaging, applications of MNPs-based materials in food processing and food packaging, health hazards, and future perspectives.
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In this study, we demonstrated the fabrication of multicontact hierarchical probes for the in vitro detection of serotonin levels. The basic three-dimensional (3D) bendable prototypes with 3 (C1), 6 (C2), or 9 (C3) contact surfaces were printed from polymeric resin via the digital light processing (DLP) technique. We chose ultrasonicated carbon fiber strands to transform these designs into multicontact carbon fiber electrodes (MCCFEs). The exposed carbon fiber (CF) surfaces were modified with aminopropyl alkoxysilane (APTMS), followed by the subsequent loading of palladium nanoclusters (PdNPs) to build active recording sites. CF functionalization with PdNPs was achieved by the wet chemical reduction of Pd(II) to Pd(0). The MCCFE configurations demonstrated an enhancement in the electroactive surface area and an improved voltammetric response toward 5-HT oxidation by increasing the points of the contacts (i.e., from C1 to C3). These MCCFEs are comparable to 3D-protruding electrodes as they can enable multipoint analyte detection. Along with the electrode patterns, morphological irregularities associated with both Pd-doped and undoped CFs supported the creation of proximal diffusion layers for facile mass transfer. Low detection limits of 0.8-10 nM over a wide concentration range, from 0.005 nM to 1 mM, were demonstrated. The MCCFE sensors had a relatively low standard deviation value of â¼2%. This type of sensitive and cost-effective electrochemical sensor may prove useful for collecting electrical impulses and long-term monitoring of 5-HT in vivo in addition to in vitro testing.
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Nanoestruturas , Serotonina , Fibra de Carbono , Oxirredução , EletrodosRESUMO
The programmed fabrication of oral dosage forms is associated with several challenges such as controlled loading and disintegration. To optimize the drug payload, excipient breakdown, and site-specific sustained release of hydrophobic drug (sulfamethoxazole, SM), we propose the development of acrylate polymer tablets enclosed with drug-loaded polycaprolactone (PCL) films. The active pharmaceutical ingredient (API) is physisorbed into the porous iron (Fe)-based metal-organic framework (MOF) and later converted to tangible PCL films, which, upon folding, are incorporated into the acrylate polymer matrices (P1/P2/P3). X-ray powder diffraction (XRPD) analysis and scanning electron microscopy (SEM) micrographs confirmed the stability and homogeneous distribution of MOF within the 50 µm thick film. Adsorption-desorption measurements at ambient temperatures confirmed the decrease in the BET surface area of PCL films by 40%, which was â¼3.01 m/g, and pore volume from 30 to 9 nm. The decrease in adsorption and surface parameters could confirm the gradual accessibility of SM molecules once exposed to a degrading environment. Fourier transform infrared (FTIR) analyses of in vitro dissolution confirmed the presence of the drug in the MOF-PCL film-enclosed tablets and concluded the cumulative SM release at pH â¼ 8.2 which followed the order SM@Fe-MOF < P1/P2/P3 < PCL-SM@Fe-MOF < P1/PCL-SM@Fe-MOF < P3/PCL-SM@Fe-MOF. The results of the study indicate that the P3/PCL-SM@Fe-MOF assembly has potential use as a biomedical drug delivery alternative carrier for effective drug loading and stimuli-responsive flexible release to attain high bioavailability.
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Materiais Biocompatíveis , Preparações de Ação Retardada , Teste de Materiais , Estruturas Metalorgânicas , Tamanho da Partícula , Poliésteres , Estruturas Metalorgânicas/química , Poliésteres/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Preparações de Ação Retardada/química , Liberação Controlada de Fármacos , Propriedades de Superfície , Portadores de Fármacos/química , Polímeros/químicaRESUMO
Fungal-bacterial combinations have a significant role in increasing and improving plant health under various stress conditions. Metabolites secreted by fungi and bacteria play an important role in this process. Our study emphasizes the significance of secondary metabolites secreted by the fungus Serendipita indica alone and by an actinobacterium Zhihengliuella sp. ISTPL4 under normal growth conditions and arsenic (As) stress condition. Here, we evaluated the arsenic tolerance ability of S. indica alone and in combination with Z. sp. ISTPL4 under in vitro conditions. The growth of S. indica and Z. sp. ISTPL4 was measured in varying concentrations of arsenic and the effect of arsenic on spore size and morphology of S. indica was determined using confocal microscopy and scanning electron microscopy. The metabolomics study indicated that S. indica alone in normal growth conditions and under As stress released pentadecanoic acid, glycerol tricaprylate, L-proline and cyclo(L-prolyl-L-valine). Similarly, d-Ribose, 2-deoxy-bis(thioheptyl)-dithioacetal were secreted by a combination of S. indica and Z. sp. ISTPL4. Confocal studies revealed that spore size of S. indica decreased by 18% at 1.9 mM and by 15% when in combination with Z. sp. ISTPL4 at a 2.4 mM concentration of As. Arsenic above this concentration resulted in spore degeneration and hyphae fragmentation. Scanning electron microscopy (SEM) results indicated an increased spore size of S. indica in the presence of Z. sp. ISTPL4 (18 ± 0.75 µm) compared to S. indica alone (14 ± 0.24 µm) under normal growth conditions. Our study concluded that the suggested combination of microbial consortium can be used to increase sustainable agriculture by combating biotic as well as abiotic stress. This is because the metabolites released by the microbial combination display antifungal and antibacterial properties. The metabolites, besides evading stress, also confer other survival strategies. Therefore, the choice of consortia and combination partners is important and can help in developing strategies for coping with As stress.
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Due to an increase in industrialization and urbanization, massive amounts of solid waste biomass are speedily accumulating in our environment, which poses several adverse effects on habitat and human health thus becoming a matter of discussion in the environmental community. With reference to the circular economy, continuous efforts have been put forward for setting up an organised management approach in combination with an efficient treatment technique for increasing the profitable utilization of solid waste. This review aims to provide a systematic discussion on the recent thermochemical technologies employed for converting waste biomass generated from different sources into valuable products like biochar, bio-oil, heat, energy and syngas. The article further focuses on a few important aspects of thermochemical conversion of waste biomass to useful products like technical factors affecting thermochemical processes, applications of by-products of thermochemical conversion, and biological pretreatment of waste biomass. The review assists interesting recent and scientific trends for boosting up the systematic management and valorization of solid waste through low-cost, efficient, environment-friendly and sustainable technologies.
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The plant rhizosphere is regarded as a microbial hotspot due to a wide array of root exudates. These root exudates comprise diverse organic compounds such as phenolic, polysaccharides, flavonoids, fatty acids, and amino acids that showed chemotactic responses towards microbial communities and mediate significant roles in root colonization. The rhizospheric microbiome is a crucial driver of plant growth and productivity, contributing directly or indirectly by facilitating nutrient acquisition, phytohormone modulation, and phosphate solubilization under normal and stressful conditions. Moreover, these microbial candidates protect plants from pathogen invasion by secreting antimicrobial and volatile organic compounds. To enhance plant fitness and yield, rhizospheric microbes are frequently employed as microbial inoculants. However, recent developments have shifted towards targeted rhizosphere engineering or microbial recruitments as a practical approach to constructing desired plant rhizospheres for specific outcomes. The rhizosphere, composed of plants, microbes, and soil, can be modified in several ways to improve inoculant efficiency. Rhizosphere engineering is achieved through three essential mechanisms: a) plant-mediated modifications involving genetic engineering, transgenics, and gene editing of plants; b) microbe-mediated modifications involving genetic alterations of microbes through upstream or downstream methodologies; and c) soil amendments. These mechanisms shape the rhizospheric microbiome, making plants more productive and resilient under different stress conditions. This review paper comprehensively summarizes the various aspects of rhizosphere engineering and their potential applications in maintaining plant health and achieving optimum agricultural productivity.