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1.
Angew Chem Int Ed Engl ; 62(37): e202307140, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37471684

RESUMEN

Elucidating single-atom effects on the fundamental properties of nanoparticles is challenging because single-atom modifications are typically accompanied by appreciable changes to the overall particle's structure. Herein, we report the synthesis of a [Cu58 H20 PET36 (PPh3 )4 ]2+ (Cu58 ; PET: phenylethanethiolate; PPh3 : triphenylphosphine) nanocluster-an atomically precise nanoparticle-that can be transformed into the surface-defective analog [Cu57 H20 PET36 (PPh3 )4 ]+ (Cu57 ). Both nanoclusters are virtually identical, with five concentric metal shells, save for one missing surface copper atom in Cu57 . Remarkably, the loss of this single surface atom drastically alters the reactivity of the nanocluster. In contrast to Cu58 , Cu57 shows promising activity for click chemistry, particularly photoinduced [3+2] azide-alkyne cycloaddition (AAC), which is attributed to the active catalytic site in Cu57 after the removal of one surface copper atom. Our study not only presents a unique system for uncovering the effect of a single-surface atom modification on nanoparticle properties but also showcases single-atom surface modification as a powerful means for designing nanoparticle catalysts.

2.
BMC Vet Res ; 18(1): 364, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36192746

RESUMEN

BACKGROUND: Selecting American mink (Neovison vison) for tolerance to Aleutian mink disease virus (AMDV) has gained popularity in recent years, but data on the outcomes of this activity are scant. The objectives of this study were to determine the long-term changes in viremia, seroconversion and survival in infected mink. Mink were inoculated intranasally with a local isolate of Aleutian mink disease virus (AMDV) over 4 years (n = 1742). The animals had been selected for tolerance to AMDV for more than 20 years (TG100) or were from herds free of AMDV (TG0). The progenies of TG100 and TG0, and their crosses with 25, 50 and 75% tolerance ancestry were also used. Blood samples were collected from each mink up to 14 times until 1211 days post-inoculation (dpi) and were tested for viremia by PCR and for anti-AMDV antibodies by counter-immunoelectrophoresis (CIEP). Viremia and CIEP status were not considered when selecting replacements. Low-performing animals were pelted and the presence of antibodies in their blood and antibody titer were measured by CIEP, and viremia and viral DNA in seven organs (n = 936) were tested by PCR. RESULTS: The peak incidences of viremia (66.7%) and seropositivity (93.5%) were at 35 dpi. The incidence of viremia decreased over time while the incidence of seroconversion increased. The least-squares means of the incidence of PCR positive of lymph node (0.743) and spleen (0.656) were significantly greater than those of bone marrow, liver, kidneys, lungs and small intestine (0.194 to 0.342). Differences in tolerant ancestry were significant for every trait measured. Incidences of viremia over time, terminal viremia, seropositivity over time, AMDV DNA in organs and antibody titer were highest in the susceptible groups (TG0 or TG25) and lowest in the tolerant groups (TG100 or TG75). CONCLUSION: Previous history of selection for tolerance resulted in mink with reduced viral replication and antibody titer. Viremia had a negative effect and antibody production had a positive effect on survival and productivity.


Asunto(s)
Virus de la Enfermedad Aleutiana del Visón , Enfermedad Aleutiana del Visón , Anticuerpos Antivirales , Formación de Anticuerpos , Visón , Viremia , Enfermedad Aleutiana del Visón/sangre , Enfermedad Aleutiana del Visón/inmunología , Enfermedad Aleutiana del Visón/mortalidad , Enfermedad Aleutiana del Visón/virología , Virus de la Enfermedad Aleutiana del Visón/genética , Virus de la Enfermedad Aleutiana del Visón/inmunología , Virus de la Enfermedad Aleutiana del Visón/aislamiento & purificación , Animales , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , ADN Viral/análisis , Femenino , Masculino , Visón/sangre , Visón/inmunología , Visón/virología , Tasa de Supervivencia , Viremia/sangre , Viremia/inmunología , Viremia/veterinaria , Viremia/virología , Replicación Viral
3.
Sensors (Basel) ; 22(14)2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35890758

RESUMEN

Cache-enabled networks suffer hugely from the challenge of content caching and content delivery. In this regard, cache-enabled device-to-device (D2D) assisted multitier cellular networks are expected to relieve the network data pressure and effectively solve the problem of content placement and content delivery. Consequently, the user can have a better opportunity to get their favored contents from nearby cache-enabled transmitters (CETs) through reliable and good-quality links; however, as expected, designing an effective caching policy is a challenging task due to the limited cache memory of CETs and uncertainty in user preferences. In this article, we introduce a joint content placement and content delivery technique for D2D assisted multitier cellular networks (D2DMCN). A support vector machine (SVM) is employed to predict the content popularity to determine which content is to be cached and where it is to be cached, thereby increasing the overall cache hit ratio (CHR). The content request is satisfied either by the neighboring node through the D2D link or by the cache-enabled base stations (BSs) of the multitier cellular networks (MCNs). Similarly, to solve the problem of optimal content delivery, the Hungarian algorithm is employed aiming to improve the quality of satisfaction. The simulation results indicate that the proposed content placement strategy effectively optimizes the overall cache hit ratio of the system. Similarly, an effective content delivery approach reduces the request content delivery delay and power consumption.


Asunto(s)
Algoritmos , Conducta Alimentaria , Simulación por Computador
4.
Sensors (Basel) ; 22(3)2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35161456

RESUMEN

Decoupled data and control planes in Software Defined Networks (SDN) allow them to handle an increasing number of threats by limiting harmful network links at the switching stage. As storage, high-end servers, and network devices, Network Function Virtualization (NFV) is designed to replace purpose-built network elements with VNFs (Virtualized Network Functions). A Software Defined Network Function Virtualization (SDNFV) network is designed in this paper to boost network performance. Stateful firewall services are deployed as VNFs in the SDN network in this article to offer security and boost network scalability. The SDN controller's role is to develop a set of guidelines and rules to avoid hazardous network connectivity. Intruder assaults that employ numerous socket addresses cannot be adequately protected by these strategies. Machine learning algorithms are trained using traditional network threat intelligence data to identify potentially malicious linkages and probable attack targets. Based on conventional network data (DT), Bayesian Network (BayesNet), Naive-Bayes, C4.5, and Decision Table (DT) algorithms are used to predict the target host that will be attacked. The experimental results shows that the Bayesian Network algorithm achieved an average prediction accuracy of 92.87%, Native-Bayes Algorithm achieved an average prediction accuracy of 87.81%, C4.5 Algorithm achieved an average prediction accuracy of 84.92%, and the Decision Tree algorithm achieved an average prediction accuracy of 83.18%. There were 451 k login attempts from 178 different countries, with over 70 k source IP addresses and 40 k source port addresses recorded in a large dataset from nine honeypot servers.

5.
Pak J Pharm Sci ; 35(1(Supplementary)): 287-295, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35228190

RESUMEN

SSTIs (Skin and soft tissue infections) are the most commonly occurring infections among all age groups. This study aimed to create an herbal emulgel for the treatment of bacterial skin infections as many bacteria have developed strong resistance against antibiotics. Spilanthe acmella plant extract contains spilanthol which has strong anti-bacterial properties. Methanolic S. acmella extract-based emulgels being promising drug delivery systems have been evaluated for various parameters like physical characteristics, viscosity, pH, spreading coefficient, Bioadhesive strength determination, Extrudability, antioxidant and antibacterial activity. 200µg/100µl exhibited the highest antioxidative activity 60.01±0.28% radical scavenging activity. MIC values of pure extract found in the range of 0.83±0.21 to 1.66±0.41µg/100µl, MBC values found in the range of 1.66±0.41 to 3.33±0.83µg/100µl for all strains of bacteria. Statistically significant antibacterial activity of all extract containing emulgels was observed against S. aureus, P. aeruginosa, E. coli p-value = 0.00, while maximum antibacterial effect all formulations have produaced zone of inhibitions against E. Coli p-value = 0.00. The current study thus suggests the use of S. acmella extract-based emulgel for the treatment of bacterial skin infections caused by S. aureus, P. aeruginosa and E. coli.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Asteraceae/química , Extractos Vegetales/farmacología , Antibacterianos/química , Antioxidantes/química , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química
6.
Pak J Pharm Sci ; 34(4(Supplementary)): 1621-1628, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34799340

RESUMEN

Given the substantial benefits of grape seed extract (GSE) in reducing oxidative stress, the study aimed development, characterization and comparative analysis of GSE-based formulations. The development entailed extraction of GSE from Vitisvinifera L. HPLC confirmed catechin, epicatechin, gallic acid, epicatechingallate and procyanidin dimers. Storage of Formulations observed, Stability & rheological parameters determined. Olive oil used as a permeability enhancer. Presence of the highest oleic acid content (65-86%) in Olive oil, skin permeability within the stratum corneum was enhanced hence better transdermal skin absorption. Using two-way ANOVA, and T-test, efficacy of formulations and impact on slowing down skin aging by countering exogenous factors of oxidative stress determined. Non-invasive biophysical technique showed emulgel substantially reduced roughness, scaliness, winkles, and sebum content by 55%, 26%, 23.9% and 30.3% respectively enhancing elasticity and hydration by 50% and 32.2% respectively. Emulsion reduced roughness, scaliness, winkles and sebum content 14%, 13%, 21% and 26.13% respectively enhancing elasticity and hydration 45.3% and 29.85% respectively. The formulations significantly offset exogenous factors of aging and impact on free radicals and oxidative stress and may be safe to incorporate bio-active botanical antioxidants for evaluation of derma cosmetic benefits in management of dehydrated and aged facial skin.


Asunto(s)
Antioxidantes/farmacología , Extracto de Semillas de Uva/farmacología , Piel/efectos de los fármacos , Adulto , Antioxidantes/química , Formas de Dosificación , Femenino , Extracto de Semillas de Uva/química , Humanos , Envejecimiento de la Piel
7.
Small ; 16(21): e1906674, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31984626

RESUMEN

Multidrug resistance of bacteria is a major challenge due to the wide-spread use of antibiotics. While a range of strategies have been developed in recent years, suppression of bacterial activity and virulence via their network of extracellular amyloid has rarely been explored, especially with nanomaterials. Here, silver nanoparticles and nanoclusters (AgNPs and AgNCs) capped with cationic branched polyethylenimine polymer are synthesized, and their antimicrobial potentials are determined at concentrations safe to mammalian cells. Compared with the ultrasmall AgNCs, AgNPs entail stronger binding to suppress the fibrillization of FapC, a major protein constituent of the extracellular amyloid matrix of Pseudomonas aeruginosa. Both types of nanoparticles exhibit concentration-dependent antibiofilm and antimicrobial properties against P. aeruginosa. At concentrations of 1 × 10-6 m or below, both the bactericidal activity of AgNCs and the antibiofilm capacity of AgNPs are associated with their structure-mediated bio-nano interactions but not ion release. For AgNPs, specifically, their antibiofilm potency correlates with their capacity of FapC fibrillization inhibition, but not with their bactericidal activity. This study demonstrates the antimicrobial potential of safe nanotechnology through the novel route of amyloidosis inhibition.


Asunto(s)
Amiloide , Proteínas Bacterianas , Biopelículas , Nanopartículas del Metal , Pseudomonas aeruginosa , Plata , Amiloide/efectos de los fármacos , Animales , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas/efectos de los fármacos , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Unión Proteica/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/genética , Plata/química , Plata/farmacología
8.
Chemistry ; 26(49): 11209-11219, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32227539

RESUMEN

The use of water splitting modules is highly desired for the sustainable production of H2 as a future energy carrier. However, the sluggish kinetics and demand of high anodic potential are the bottlenecks for half-the cell oxygen evolution reaction (OER), which severely hamper the overall conversion efficiency. Although transition metal oxides based electrocatalysts have been envisioned as cost-effective and potential contenders for this quest, nevertheless, their low conductivity, instability, and limited number of active sites are among the common impediments that need to be addressed to eventually enhance their inherent catalytic potential for enhanced OER activity. Herein, the controlled assembly of transition metal oxides, that is, Cu@CuOx nanoclusters (NCs, ≈2 nm) and Co@CoOx beaded nanoclusters (BNCs, ≈2 nm), on thiol-functionalized graphene oxide (G-SH) nanosheets is reported to form novel and highly efficient electrocatalysts for OER. The thiol (-SH) functionality was incorporated by selective epoxidation on the surface of graphene oxide (GO) to achieve chemically exfoliated nanosheets to enhance its conductivity and trapping ability for metal oxides in nanoscale dimensions (≈2 nm). During the electrocatalytic reaction, overpotentials of 290 mV and 310 mV are required to achieve a current density of 10 mA cm-2 for BNCs and NCs, respectively, and the catalysts exhibit tremendous long-term stability (≈50 h) in purified alkaline medium (1 m KOH) with no dissolution in the electrolyte. Moreover, the smaller Tafel slopes (54 mV/dec for BNCs and 66 mV/dec for NCs), and a Faradic efficiency of approximately 96 % indicate not only the selectivity but also the tailored heterogeneous electrons transfer (HET) rate, which is required for fast electrode kinetics. It is anticipated that such ultrasmall metal oxide nanoclusters and their controlled assembly on a conducting surface (G-SH) may offer high electrochemical accessibility and a plethora of active sites owing to the drastic decrease in dimensions and thus can synergistically ameliorate the challenging OER process.

9.
J Sep Sci ; 43(20): 3921-3930, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32844548

RESUMEN

This study aims to introduce a simple, sensitive, and cost-effective method for the simultaneous determination of acetamiprid and its main metabolite 6-chloronicotinic acid in environmental samples by using a nonsuppressed ion chromatography hyphenated with an online postcolumn photoinduced fluorescence detection system. The fluorescence detector wavelengths λex /λem  = 257/382 nm was set for up to 6.0 min for acetamiprid, while λex /λem  = 231/370 nm programmed for 6-chloronicotinic acid for the rest of the analysis time. Both samples were treated by applying miniaturized quick, easy, cheap, effective, rugged, and safe method before the separation of analytes on an IonPac® AS11-HC column by pumping 40 mM NaOH having minuscule content of acetonitrile (5%, v/v) as an eluent. Both intrinsically nonfluorescent analytes were turned-on by online postcolumn photoinduced derivatization, avoiding the need for complex chemical derivatization or addition of a postcolumn extra pump. The developed method was appraised for the analysis of environmental samples, exhibiting excellent linearity (0.050-10 µg/mL) with a correlation coefficient greater than 0.9993 for both analytes. Whereas, obtained limit of detection (0.025-0.0072 µg/mL), recoveries (98.02-116.00%), and inter- and intraday precision (≤3.02 %) were satisfactory for both compounds in environmental samples.

10.
Chem Soc Rev ; 48(2): 415-427, 2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30462112

RESUMEN

The dramatic increase in antimicrobial resistance for pathogenic bacteria constitutes a key threat to human health. The Centers for Disease Control and Prevention has recently stated that the world is on the verge of entering the "post-antibiotic era", one where more people will die from bacterial infections than from cancer. Recently, nanoparticles (NPs) have emerged as new tools that can be used to combat deadly bacterial infections. Nanoparticle-based strategies can overcome the barriers faced by traditional antimicrobials, including antibiotic resistance. In this tutorial review, we have highlighted multiple nanoparticle-based approaches to eliminate bacterial infections, providing crucial insight into the design of elements that play critical roles in creating antimicrobial nanotherapeutics. In particular, we have focused on the pivotal role played by NP-surface functionality in designing nanomaterials as self-therapeutic agents and delivery vehicles for antimicrobial cargo.


Asunto(s)
Portadores de Fármacos/química , Farmacorresistencia Bacteriana/efectos de los fármacos , Nanopartículas/toxicidad , Antibacterianos/farmacología , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Humanos , Nanopartículas/química , Nanopartículas/uso terapéutico , Polímeros/química , Propiedades de Superficie
11.
Sensors (Basel) ; 20(7)2020 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-32283800

RESUMEN

Faults and failures are familiar case studies in centralized and decentralized tracking systems. The processing of sensor data becomes more severe in the presence of faults/failures and/or noise. Effective schemes have been presented for decentralized systems, in the presence of faults only. In some practical scenarios of systems, there are certain interruptions in addition to these faults. These interruptions may occur in the form of noise. However it is expected that the decision about the sensor data is difficult in the presence of noise. This is because the noise adversely affects the communication amongst sensors and the processing unit. More complexity is expected when there are faults and noise simultaneously. To deal with this problem, in addition to existing fault detection and isolation schemes, the Kalman filter is employed. Here, a generic discussion is provided, which is equally applicable to other situations. This work addresses various faults in the presence of noise for decentralized tracking systems. Local single faults and multiple faults in the presence of noise are the core issues addressed in this paper. The proposed work is comprised of a general scenario for a decentralized tracking system followed by a case study of a target tracking scenario with and without noise. The presented schemes are also tested for different types of faults. The proposed work presents effective tracking in the presence of noise and faults. The results obtained demonstrate the acceptable performance of the scheme of this work.

12.
AAPS PharmSciTech ; 21(2): 68, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31950394

RESUMEN

Microneedle patch is a prominent strategy with minimal invasion and painless application to improve skin penetration of drug molecules. Herein, we report microneedle patch (MNP) as an alternative to the oral route for the systemic delivery of tacrolimus (TM), an immunosuppressant drug. Thiolated chitosan (TCS) based microneedle patch was fabricated and characterized in vitro and in vivo for its mechanical strength, skin penetration, drug release, and skin irritation. The MNP having 225 needles with 575 µm showed good mechanical properties in terms of tensile strength and percentage elongation. The skin penetration showed 84% penetration with no breakage. Histology of the mice skin after insertion showed the penetration of needles into the dermis. In vitro release and ex vivo permeation studies through Franz diffusion cell showed the sustained release (82.5%) of TM from the MNP with significantly higher (p < 0.05) skin permeation as compared with controls, respectively. Moreover, in vivo biocompatibility in rats showed the safety of the material and patch. Thus, the TCS microneedle patch has the potential to be developed as a transdermal delivery system for tacrolimus with improved bioavailability and sustained release over a longer period.


Asunto(s)
Quitosano/química , Inmunosupresores/administración & dosificación , Tacrolimus/administración & dosificación , Parche Transdérmico , Animales , Cámaras de Difusión de Cultivos , Disulfuros/química , Sistemas de Liberación de Medicamentos , Diseño de Equipo , Microinyecciones , Agujas , Ratas , Piel/metabolismo , Compuestos de Sulfhidrilo , Resistencia a la Tracción
13.
J Pak Med Assoc ; 70(8): 1418-1424, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32794498

RESUMEN

Metabesity refers to metabolic aberrations associated with obesity. These include low- grade inflammation, mitochondrial dysfunction, and changes in gut microbiome. Along with a genetic component, the phenotypes in metabesity are largely the result of sedentary lifestyle and unhealthy eating habits. Metabesity is associated with several co-morbidities including an increased risk for cardiovascular conditions like hypertension, heart failure, myocardial infarction, stroke, and sudden death. Insulin resistance, high blood pressure and glucose levels, visceral adiposity, progressive atherosclerosis, dyslipidaemia and fatty liver are common in obese individuals. Obesity increases the risk for and overall mortality due to cancer. Metabesity adversely impacts endocrine balances in the body and increases the risk of degenerative conditions like dementia. Metabesity is an impending epidemic of huge public health implications with enormous clinical, socioeconomic, and humanistic burden. Interventions to combat sedentary lifestyle and unhealthy eating should be introduced early in life to prevent the onset and progression of metabesity. This review also summarizes the experts' recommendation from Pakistan to manage the rising metabesity concern in their geography based on the literature evidences.


Asunto(s)
Enfermedades Cardiovasculares , Hígado Graso , Resistencia a la Insulina , Humanos , Obesidad/epidemiología , Obesidad/prevención & control , Pakistán , Factores de Riesgo
14.
J Relig Health ; 59(5): 2458-2468, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31273673

RESUMEN

This study focused on examining the effects of personality traits in moderating relationship between religiosity and mental health of university students. It was conducted on a sample of (N = 372) university students aged between 20 and 26 years equated to gender: 186 male and 186 female students at Bahauddin Zakariya University Multan. The religiosity, mental health and personality traits were measured by using the scale of Religiosity of Islam, Inventory of Mental Health and Big Five Inventory, respectively. The correlation analyses showed the significant relationship of religiosity with behavioral control but negatively associated with anxiety and depression as two dimensions of mental health. The results further demonstrated that openness to experience and agreeableness as traits of students' personality considerably moderated the relationship of religiosity and mental health.


Asunto(s)
Salud Mental , Universidades , Adulto , Ansiedad , Femenino , Humanos , Masculino , Personalidad , Inventario de Personalidad , Estudiantes , Adulto Joven
15.
Chemistry ; 25(2): 548-555, 2019 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-30270511

RESUMEN

A very simple and facile methodology is used to prepare dithiocarbamate-functionalized hollow microporous organic capsules (HMOCs-DTC), which exhibit excellent stability, a high surface area, and appropriate microporous architecture. In this strategy, SiO2 particles are used as templates to construct PS-DVB-MAA microspheres, and then dithiocarbamate groups are grafted onto them. The dithiocarbamate-functionalized hypercrosslinked microporous organic capsules (HMOCs-DTC/GC) are then used as an electrode material for the detection of CuII ions. Cyclic voltammetry (CV) and electron impedance spectroscopy (EIS) are exploited to study the electrochemical potential of the designed material. The placement of functional groups (dithiocarbamate) at the mesopore interface effectively enhances the mass transfer, which facilitates the more selective detection of CuII ions. The high sensitivity of the modified electrode is expressed in terms of current (Ip ) enhancement at extremely low concentrations of CuII ions. Thus, a functional and robust porous material (HMOCs-DTC) presents a sensitive sensing ability, displaying the calibration response over a wide linear range (2.50×10-11 -3.50×10-10 m), with a lowest limit of detection of 1.02×10-11 m. Indeed, these HMOCs present a new class of porous polymers possessing extraordinarily high scalability but avoiding complex and expensive synthetic methodologies, promoting its practical utilization.

16.
Langmuir ; 35(27): 8996-9003, 2019 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-31189312

RESUMEN

Tainting of waterbodies with noxious industrial waste is the gravest environmental concern of the day that continues to wreak inevitable havoc on human health. To cleanup these hard-to-remove life-threatening water contaminants, we have prepared hierarchically porous poly(acrylic acid) beads by emulsion templating. These emulsion-templated macroporous polymer beads not only mediate the synthesis of Fe3O4 nanoparticles inside their porous network using a coprecipitation approach but, in turn, create diverse anchoring sites to immobilize an additional poly(acrylic acid) active layer onto the nanocomposite beads. These post-synthetically modified nanocomposite beads with macropores and abundant acrylic acid moieties offer the ready mass transfer and fair advantage of relatively higher overall negative charge to efficiently adsorb lead [Pb(II)] and crystal violet with impressive performance-even superior to many of the materials explored in this regard so far. Furthermore, the strong entanglement of nanoparticles in the porous polymeric scaffolds tackles the curb of trade-off between all-round effective remediation and secondary pollution and the millimeter size eases their processing and recovery during the adsorption tests, thereby making these materials practically worthwhile.

17.
Langmuir ; 35(40): 13165-13173, 2019 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-31525878

RESUMEN

Emulsion templating has emerged as a cutting-edge technique to prepare a wide array of porous polymer-metal nanocomposites with intriguing properties. Using this strategy, we set out to prepare novel hierarchically porous poly(vinylsulfonic acid) beads, which were then used for the in situ production of silver nanoparticles to obtain poly(vinylsulfonic acid)-Ag nanocomposite beads via a facile approach. Owing to their multimodal macro-meso-/microporosity that accounts for their decent BET surface areas (170.75-197.74 m2/g) and easier mass diffusion and transport together with the synergistic benefits of very small silver nanoparticles (down to ∼3.77 nm), the nanocomposite beads are found effective to remove Hg(II) and RhB and to kill Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. The adsorption capacities (167.98-190.58 mg/g) of these materials for Hg(II) surpass some recently reported benchmark materials. The larger size (1.56 ± 0.20-1.50 ± 0.14 mm) of the beads that helps favor the handling and subsequent recovery for recycling is also very useful to further broaden the horizons of these materials to develop decentralized water treatment systems.

18.
Mikrochim Acta ; 186(2): 127, 2019 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-30684013

RESUMEN

This study reports on a simple approach for the fabrication of an electrode modified with biocompatible C-dot wrapped ZnO nanoparticles for selective photoelectrochemical monitoring of H2O2 released from living cells. The biocompatibility of the ZnO nanoparticles was confirmed through in-vitro cellular testing using the MTT assay on Huh7 cell lines. The ZnO nanoparticles wrapped with dopamine-derived C-dots possess numerous catalytically active sites, excessive surface defects, good electrical conductivity, and efficient separation ability of photo-induced electrons and holes. These properties offer highly sensitive and selective non-enzymatic photo-electrochemical monitoring of H2O2 released from HeLa cells after stimulation with N-formylmethionyl-leucyl-phenylalanine. The sensor has a wide linear range (20-800 nM), low detection limit (2.4 nM), and reliable reproducibility, this implying its suitability for biological and biomedical applications. Graphical abstract Schematic of the fabrication of ZnO nanoparticles by using a plant extract as a reducing agent. Wrapping of ZnO with C-dots enhances the photoelectrocatalytic efficacy. Sensitive and selective photoelectrochemical monitoring of H2O2 released from cancer cells is demonstrated.


Asunto(s)
Carbono/química , Electroquímica/instrumentación , Peróxido de Hidrógeno/metabolismo , Procesos Fotoquímicos , Puntos Cuánticos/química , Supervivencia Celular , Electrodos , Células HeLa , Humanos , Límite de Detección , Óxido de Zinc/toxicidad
19.
Trop Anim Health Prod ; 51(6): 1357-1365, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30706330

RESUMEN

The first objective of the present study was to evaluate if the antibodies induced by the live LaSota and killed Newcastle disease (sub-genotype VIIi) vaccines protect the chickens against exposure with pathogenic avian avulavirus-1 (AAvV-1) of chicken and/or pigeon origins. The second objective was to study the effect of vaccines on stressed birds (dexamethasone, aflatoxin, and heat stressed) with respect to antibody production and protection against pathogenic AAvV-1 challenge. Sixty-one-day-old Hubbard chickens were divided into six groups (gA-gF) with ten animals each. All the groups received LaSota (105 EID50, 0.1 ml per chick) on days 7 and 27 via eye drop and one intramuscular injection of a killed vaccine (sub-genotype VIIi) (107.5 EID50, 1 ml) on day 18, except the control birds received the PBS only. Moreover, group gC-DEX received dexamethasone intramuscularly at a dose rate of 1-mg/kg body weight daily; gD-AFLA had received aflatoxin as oral gavage at a dose rate of 30 ppb daily, and gE-HEAT was kept under heat stressed (38 °C) till challenged. All the groups were challenged with AAvV-1 strain of chicken origin of sub-genotype VIIi, except the group gA-pigeon was challenged with pigeon-origin strain (sub-genotype VIm). The result showed that the gA-pigeon and gB-chicken vaccinate showed 100% and 80% protection. The immunosuppressive birds produced low pre-challenge HI titer, and protection was observed at 40%, 50%, and 70% in gC-DEX, gD-AFLA, and gE-HEAT, respectively. Our findings suggest the stress factors such as aflatoxin in the feed and dexamethasone are immunosuppressive in nature and suppress the immune response and its associated protective role during infection.


Asunto(s)
Enfermedad de Newcastle/prevención & control , Virus de la Enfermedad de Newcastle/inmunología , Animales , Anticuerpos Antivirales/genética , Pollos/inmunología , Genotipo , Vacunas de Productos Inactivados , Vacunas Virales/inmunología
20.
Appl Microbiol Biotechnol ; 101(20): 7715-7728, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28920150

RESUMEN

This study examines the bioremediation potential and cadmium-induced cellular response on a molecular level in Candida tropicalis 3Aer. Spectroscopic analysis clearly illustrated the involvement of yeast cell wall components in biosorption. Cadmium bioaccumulation was confirmed by TEM, SEM, and EDX examination. TEM images revealed extracellular as well as cytoplasmic and vacuolar cadmium nanoparticle formation, further validated by presence of ycf1 gene and increased biosynthesis of GSH under cadmium stress. Fourteen proteins exhibited differential expression and during cellular redox homeostasis are found to involve in nitrogen metabolism, nucleotide biosynthesis, and carbohydrate catabolism. Interestingly, C. tropicalis 3Aer is equipped with nitrile hydratase enzyme, rarely been reported in yeast. It has the potential to remove nitriles from the environment. The Cd+2 toxicity not only caused growth stasis but also upregulated the cysteine biosynthesis, protein folding and cytoplasmic detoxification response elements. The present study suggests that C. tropicalis 3Aer is a potential candidate for bioremediating environmental pollution by Cd+2.


Asunto(s)
Cadmio/metabolismo , Candida tropicalis/efectos de los fármacos , Candida tropicalis/fisiología , Cationes Bivalentes/metabolismo , Contaminantes Ambientales/metabolismo , Cadmio/toxicidad , Candida tropicalis/genética , Candida tropicalis/ultraestructura , Cationes Bivalentes/toxicidad , Contaminantes Ambientales/toxicidad , Perfilación de la Expresión Génica , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Espectrometría por Rayos X , Estrés Fisiológico
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