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1.
Mol Pharm ; 20(2): 1382-1393, 2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36583939

RESUMEN

The study aimed to improve the treatment of impetigo with naturally occurring quercetin and its copper-quercetin (Cu-Q) complex by preparing sustained-release (SR) nanoparticles of polycaprolactone (PCL). The solvent evaporation method was used for the copper-quercetin (Cu-Q) complex formation, and their PCL nanoparticles (PCL-NPs, Q-PCL-NPs, and Cu-Q-PCL-NPs) were prepared by the high-pressure homogenization method. Synthesis of nanoparticles was confirmed by their physicochemical and antibacterial properties of quercetin against Gram-positive as well as Gram-negative bacteria. The percentage loading efficiency of quercetin and release in 100 mM of phosphate buffer pH 7.4 and 5.5 at 37 °C was found to be more than 90% after 24 h with the zero-order release pattern. Minimum inhibitory concentration of nanoparticles was found to increase threefold in the case of Cu-Q-PCL-NPs may be due to the synergistic antibacterial behavior. Scanning electron microscopy showed spherical nanoparticles, and surface roughness was confirmed by atomic force microscopy analysis. Fortunately, no sign of irritation on rat skin even at 3%, was seen. In vitro antioxidant assay by 2,2-diphenyl-1-picrylhydrazyl reduction was found to be ≤80 ± 0.02% which confirmed their scavenging activity. Interestingly, for the ex vivo study, the tape-stripping model was applied against Staphylococcus aureus containing rats and showed the formation of the epidermal layer within 4-5 days. Confirmation of antibacterial activity of pure quercetin, from Cu-Q complex, and their SR release from Q-PCL-NPs and Cu-Q-PCL-NPs was considered an effective tool for the treatment of skin diseases and can be used as an alternative of already resistant ciprofloxacin in impetigo.


Asunto(s)
Impétigo , Nanopartículas , Ratas , Animales , Quercetina/farmacología , Quercetina/uso terapéutico , Quercetina/química , Cobre/química , Preparaciones de Acción Retardada , Nanopartículas/química , Antibacterianos/farmacología , Antibacterianos/química
2.
Nanotechnology ; 34(47)2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37671986

RESUMEN

This study emphasizes the significance of optimizing heat transmission, energy conversion, and thermal management in electronic devices, renewable energy systems, and emerging technologies like thermoelectric devices and energy storage systems. The aim is to enhance heat transfer efficiency for improved performance and lifespan of electronic equipment. The research utilizes a mathematical flow analysis to study a water-based ternary nanofluid's flow and thermal characteristics in a vertical microfluidic channel driven by peristalsis and electroosmosis. The ternary-hybrid nanofluid (THNF), comprising copper, silver, and alumina nanoparticles dissolved in water, is examined considering induced magnetic fields. The study delves into fluid flow, heat absorption, and mixed convection, using Debye-Hückel, lubrication, and long wavelength approximations. Results show that THNF exhibits superior heat transmission compared to pure water. Increasing solid volume fraction of nanoparticles decreases THNF's temperature. Induced magnetic fields impact the system. This research could influence thermal pipe heat sinks and bioengineered medical devices design.

3.
J Biol Phys ; 46(1): 45-65, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32052248

RESUMEN

The study of heat and electroosmotic characteristics in the flow of a third-order fluid regulated by peristaltic pumping is examined by using governing equations, i.e., the continuity equation, momentum equation, energy equation, and concentration equation. The wavelength is considered long compared to its height and a low Reynolds number is assumed. The velocity slip condition is employed. Analytical solutions are performed through the perturbation technique. The expressions for the dimensionless velocity components, temperature, concentration, and heat transfer rate are obtained. Pumping features were computed numerically for discussion of results. Trapping and heat transfer coefficient distributions were also studied graphically. The findings of the present study can be applied to design biomicrofluidic devices like tumor-on-a-chip and organ-on-a-chip.


Asunto(s)
Electroósmosis/instrumentación , Calor , Hidrodinámica , Modelos Teóricos
4.
Bioconjug Chem ; 30(1): 13-28, 2019 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-30508381

RESUMEN

For SLN lymph node biopsy (SLNB), SLN mapping has become a standard of care procedure that can accurately locate the micrometastases disseminated from primary tumor sites to the regional lymph nodes. The broad array of SLN mapping has prompted the development of a wide range of SLN tracers, rationally designed for noninvasive and high-resolution imaging of SLNs. At present, conventional SLN imaging probes (blue dyes, radiocolloids, and few other small-molecular dyes), although serving the clinical needs, are often associated with major issues such as insufficient accumulation in SLN, short retention time, staining of the surgical field, and other adverse side effects. In a recent advancement, newly designed fluorescent nanoprobes are equipped with novel features that could be of high interest in SLN mapping such as (i) a unique niche that is not met by any other conventional SLN probes, (ii) their adoptable synthesis method, and (ii) excellent sensitivity facilitating high resolution SLN mapping. Most importantly, lots of effort has been devoted for translating the fluorescent nanoprobes into a clinical setup and also imparting the multimodal imaging abilities of nanoprobes for the excellent diagnosis of life-threatening diseases such as cancer. In this review, we will provide a detailed roadmap of the progress of a wide variety of current fluorescent molecular probes and emphasize the future of nanomaterial-based single/multimodal imaging probes that have true potential translation abilities for SLN mapping.


Asunto(s)
Colorantes Fluorescentes/química , Sondas Moleculares/química , Biopsia del Ganglio Linfático Centinela/métodos , Animales , Humanos , Verde de Indocianina/química , Metástasis Linfática , Micrometástasis de Neoplasia , Teoría Cuántica , Ganglio Linfático Centinela/patología , Solubilidad
5.
Pak J Pharm Sci ; 32(3 (Supplementary)): 1137-1143, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31303582

RESUMEN

The aim of study was cross linking of high molecular weight chitosan nanoparticles containing 5-fluorouracil to improve dissolution rate and ultimately enhance its bioavailability by reverse emulsion/micelles method and cross-linking agent i.e. glutaraldehyde (GA 25% aqueous solution in water). The nature and outer morphologies were evaluated by scanning electron microscopy (SEM). Drug release models were functional to support way from cross linked NPs. Cross linking of 5-fluorouracil with glutaraldehyde improved dissolution rate. Mean dissolution time of 5-fluorouracil decreased significantly upon reverse emulsion/cross linking as encapsulated drug is protective and thermally stable within cross linked chitosan NPs. FTIR studies showed formation of intermolecular hydrogen bonding between 5-fluorouracil and GA-co-CHNPs. DSC studies indicated a less crystalline state of 5-fluorouracil in cross linking. SEM showed spherical nanoparticles with somewhat rough surface. 5-FU release followed Korsmeyer-Peppas model which indicate diffusion and dissociation control drug release from GA-co-CH-NPs. 5-FU cross linked chitosan nanoparticles can be safe and useful tool for other chemotherapeutic agents.


Asunto(s)
Quitosano/química , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Fluorouracilo/farmacocinética , Nanopartículas/química , Disponibilidad Biológica , Rastreo Diferencial de Calorimetría , Reactivos de Enlaces Cruzados/química , Estabilidad de Medicamentos , Fluorouracilo/química , Glutaral/química , Enlace de Hidrógeno , Microscopía Electrónica de Rastreo , Peso Molecular , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
6.
J Sep Sci ; 39(4): 793-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26632078

RESUMEN

In the present work, novel molecularly imprinted polymer porous beads for the selective separation of copper ions have been synthesized by combining two material-structuring techniques, namely, molecular imprinting and oil-in-water-in-oil emulsion polymerization. This method produces monodisperse spherical beads with an average diameter of ∼2-3 mm, in contrast to adsorbents produced in the traditional way of grinding and sieving. Field-emission scanning electron microscopy indicates that the beads are porous in nature with interconnected pores of about 25-50 µm. Brunner-Emmett-Teller analysis shows that the ion-imprinted beads possess a high surface area (8.05 m(2) /g), and the total pore volume is determined to be 0.00823 cm(3) /g. As a result of the highly porous nature and ion-imprinting, the beads exhibit a superior adsorption capacity (84 mg/g) towards copper than the non-imprinted material (22 mg/g). Furthermore, selectivity studies indicate that imprinted beads show splendid recognizing ability, that is, nearly fourfold greater selective binding for Cu(2+) in comparison to the other bivalent ions such as Mn(2+) , Ni(2+) , Co(2+) , and Ca(2+) . The imprinted composite beads prepared in this study possess uniform porous morphology and may open up new possibilities for the selective removal of copper ions from waste water/contaminated matrices.

7.
Analyst ; 140(21): 7366-72, 2015 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-26381602

RESUMEN

Salmonella enterica serotype Typhi (S. Typhi) is the causative agent of typhoid fever and remains a major health threat in most of the developing countries. The prompt diagnosis of typhoid directly from the patient's blood requires high level of sensitivity and specificity. Some of us were the first to report PCR based diagnosis of typhoid. This approach has since then been reported by many scientists using different genomic targets. Since the number of bacteria circulating in the blood of a patient can be as low as 0.3 cfu ml(-1), there is always a room for improvement in diagnostic PCR. In the present study, the role of different types of nanoparticles was investigated to improve the existing PCR based methods for diagnosis and strain typing of S. Typhi (targeting Variable Number of Tandem Repeats [VNTR]) by using optimized PCR systems. Three different types of nanoparticles were used i.e., citrate stabilized gold nanoparticles, rhamnolipid stabilized gold and silver nanoparticles, and magnetic iron oxide nanoparticles. The non-specific amplification was significantly reduced in VNTR typing when gold and silver nanoparticles were used in an appropriate concentration. More importantly, the addition of nanoparticles decreased the non-specificity to a significant level in the case of multiplex PCR thus further validating the reliability of PCR for the diagnosis of typhoid.


Asunto(s)
Técnicas de Tipificación Bacteriana , Nanopartículas del Metal/química , Reacción en Cadena de la Polimerasa/métodos , Salmonella typhi/clasificación , Fiebre Tifoidea/diagnóstico , Fiebre Tifoidea/microbiología , Proteínas Bacterianas/química , Cartilla de ADN/química , Proteínas de Escherichia coli/genética , Compuestos Férricos/química , Flagelina , Oro/química , Magnetismo , Repeticiones de Minisatélite , Nanotecnología/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Plata/química , Temperatura
8.
Sci Rep ; 14(1): 20767, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39237537

RESUMEN

This study aims to enhance the tribological properties of automotive applications by examining the effects of TiC content on the microstructure, mechanical properties, and wear behavior. This study investigates the production of Al-TiC composite strips using a novel multi-step densification process combining mechanical alloying and hot rolling with TiC concentrations ranging from 0 to 12 vol%. The novelty of this work lies in its comprehensive approach to developing and analyzing Al-TiC composite strips using a multistep densification method. This study integrates microstructural analysis, mechanical property evaluation, and detailed tribological behavior assessment under different wear loads (5-25 N). A key innovation is the application of the Abbott Firestone method to analyze worn surfaces, providing insights into optimal wear conditions. The study reveals that increasing the TiC content to 12 vol% significantly improves densification, hardness (up to 268.8% increase), and wear resistance (up to 95% improvement at a 5N load). Dry ball-on-flat sliding wear tests at loads of 5-25N demonstrate that TiC particles hindered complete delamination wear in the composite strips. The Abbott Firestone method analysis of worn surfaces indicated an optimal exploitation zone in the Al-6 vol% TiC composite at both low and high wear loads. This comprehensive approach provides valuable insights into optimizing Al-TiC composites for enhanced performance in automotive components that require improved wear resistance.

9.
Sci Rep ; 14(1): 2862, 2024 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-38311645

RESUMEN

More focus has recently been placed on enhancing the strength, elastic modulus, coefficient of thermal expansion (CTE), wear and corrosion resistance, and other qualities of aluminum (Al) alloys by varying the quantity of ceramics added for a range of industrial uses. In this regard, Al-4.2-Cu-1.6Mg matrix nanocomposites reinforced with nano-ZrO2 particles have been created using the powder metallurgy approach. The microstructure and particle size distributions of the produced powders were analyzed using a diffraction particle size analyzer, XRD, TEM, and SEM. To achieve good sinterability, the powders were compacted and sintered in argon. The sintered nanocomposites' mechanical, elastic, and physicochemical characteristics were measured. Additionally, the behavior of corrosion, wear, and thermal expansion were examined. The results showed a decrease in the particle sizes of the Al-Cu-Mg alloy by adding ZrO2 nanoparticles up to 45.8 nm for the composite containing 16 wt.% ZrO2. By increasing the sintering temperature to 570 °C, the densification of nanocomposites was enhanced. Also, the coefficient of thermal expansion and wear rate remarkably decreased by about 28 and 37.5% by adding 16 wt.% ZrO2. Moreover, microhardness yield, strength, and Young's modulus were enhanced to 161, 145, and 64%, respectively, after adding 16 wt.% ZrO2. In addition, increasing the exposure time was responsible for decreasing the corrosion rate for the same sample.

10.
Int J Biol Macromol ; 277(Pt 4): 134167, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39067724

RESUMEN

Diarrhea is a globally major problem especially Escherichia coli induced diarrhea becoming fatal nowadays in developing countries. Colon-targeted chitosan microspheres (Ms) comprising of lipase­zinc and lipase­copper complexes were prepared, loaded with Attapulgite (Cts-Li-Zn-ATG/Ms and Cts-Li-Cu-ATG/Ms) for the treatment of bacterial diarrhea. Thin layer chromatography (TLC) and Fourier-transform infrared spectroscopy (FTIR) studies were used for confirmation of proposed lipase-metal complexes. Ms showed particle size range 18 ± 0.24 to 23 ± 0.83 µm, zeta potential -13.7 ± 0.71 to -29.3 ± 1.34 mV, PDI 0.5 ± 0.04 to 1.0 ± 0.07 and hemolytic activity was found to be <5 ± 1.25 %. After coating with Eudragit S-100 for colon targeting, in-vitro % drug release of ATG at pH 7.4 was 80 ± 0.21 % for Eud-Cts-Li-Zn-ATG/Ms while it was increased to 83 ± 0.54 % for Eud-Cts-Li-Cu-ATG/Ms within 7 h, respectively. In-vivo anti-diarrheal activity of Eud-Cts-Li-Zn-ATG/Ms and Eud-Cts-Li-Cu-ATG/Ms was performed by oral challenge on albino mice having infectious diarrhea colonized with E. coli. Results revealed significant anti-diarrheal effect of proposed Eud-Cts-Li-Cu-ATG/Ms in terms of weight gain from 24 ± 0.12 g to 26.05 ± 0.31 g, which was 2-fold increase as compared to Eud-Cts-Li-Zn-ATG/Ms. Conclusively, Eud-Cts-Li-Cu-ATG/Ms provides an innovative alternate for the treatment of bacterial diarrhea with additional support of chitosan and lipase for nutritional support and immunity which was compromised in diarrheal patients.


Asunto(s)
Quitosano , Cobre , Diarrea , Escherichia coli , Lipasa , Compuestos de Magnesio , Microesferas , Compuestos de Silicona , Cobre/química , Quitosano/química , Animales , Diarrea/tratamiento farmacológico , Diarrea/microbiología , Escherichia coli/efectos de los fármacos , Ratones , Compuestos de Magnesio/química , Compuestos de Magnesio/farmacología , Lipasa/metabolismo , Compuestos de Silicona/química , Compuestos de Silicona/farmacología , Liberación de Fármacos , Portadores de Fármacos/química , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología
11.
Sci Rep ; 14(1): 19023, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39152151

RESUMEN

Owing to their exceptional mechanical properties, the various welding wires used to combine aluminum can meet the needs of many engineering applications that call for components with both good mechanical and lightweight capabilities. This study aims to produce high-quality welds made of AA7075 aluminum alloy using the GTAW technique and various welding wires, such as ER5356, ER4043, and ER4047. The microstructure, macrohardness, and other mechanical characteristics, such as tensile strength and impact toughness, were analyzed experimentally. To check the fracture surface of the AA7075 welded joints, the specimens were examined using optical and scanning electron microscopy (SEM). A close examination of the samples that were welded with ER5356 welding wire revealed a fine grain in the weld zone (WZ). In addition, the WZ of the ER4043 and ER4047 welded samples had a coarse grain structure. Because the hardness values of the welded samples were lower in the WZ than in the base metal (BM) and heat-affected zone (HAZ), the joints filled with ER5356 welding wire provided the highest hardness values compared to other filler metals. Additionally, the ER4047 filler metal yielded the lowest hardness in the weld zone. The welding wire of ER5356 produced the greatest results for ultimate tensile stress, yield stress, welding efficiency, and strain-hardening capacity (Hc), whereas the filler metal of ER4043 produced the highest percentage of elongation. In addition, the ER4047 fracture surface morphology revealed coarser and deeper dimples than the ER5356 fine dimples in the welded joints. Finally, the highest impact toughness was obtained at joints filled with the ER4047 filler metal, whereas the lowest impact toughness was obtained at the BM.

12.
ACS Appl Mater Interfaces ; 15(37): 43321-43331, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37668507

RESUMEN

The emergence of antimicrobial resistance is an alarming global health concern and has stimulated the development of novel functional nanomaterials to combat multi-drug-resistant (MDR) bacteria. In this work, we demonstrate for the first time the synthesis and application of surfactin-coated silver nanoparticles as an efficient antibacterial and antibiofilm agent against the drug-resistant bacteria Pseudomonas aeruginosa for safe dermal applications. Our in vivo studies showed no significant superficial dermal irritation, edema, and erythema, while microscopic analysis revealed that surfactin-coated silver nanoparticles caused no pathological alterations at the applied concentrations. These results support the potential use of surfactin-coated silver nanoparticles against drug-resistant bacterial biofilm infections and in skin wound dressing applications.


Asunto(s)
Nanopartículas del Metal , Pseudomonas aeruginosa , Plata/farmacología , Antibacterianos/farmacología , Biopelículas
13.
J Nanosci Nanotechnol ; 12(3): 1967-71, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22755006

RESUMEN

The conducting metal oxide (ZnO, Cu2O) films were used for fabrication of p-n heterojunction by rf sputtering and electrodeposition techniques respectively. The as synthesized films were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV spectroscopy and electrical techniques. The electrical properties of the p-Cu2O/n-ZnO heterojunction were examined using the current-voltage measurements. The current-voltage (I-V) result showed that potential barrier was higher than the turn-on voltage, which was attributed to the presence of the interface defect states. The PN junction parameters such as ideality factor, barrier height, and series resistance were determined using conventional forward bias current-voltage characteristics. The annealing of Cu2O increase the crystallinity size and which enhance the photo current from 1.6 mA/cm2 to 3.7 mA/cm2. The annealing of respective film resulted in a decrease of these parameters with an increase in efficiency of solar cell from 0.14% to 0.3% at 350 degrees C.

14.
West Indian Med J ; 61(2): 139-44, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23155958

RESUMEN

AIM: To study the correlation of nasal Staphylococcus aureus carrier status in patients on haemodialysis, infected by hepatitis C virus (HCV), hepatitis B virus (HBV), and their sociodemographic features. SUBJECTS AND METHODS: A survey, including patients' sociodemographic features, was applied to patients by physicians in face to face interviews. Medical records regarding their serologic data were recorded from haemodialysis centres. Nasal swab samples of 2 cm depth from both nostrils of patients were obtained for nasal culture. Samples were inoculated in 5% sheep blood agar and incubated in an incubator at a temperature of 37 degrees C for 24 hours. The results were studied by the same microbiologist. RESULTS: A total of 185 patients were enrolled in the study. According to culture results, 14.1% of patients (n = 26) had methicillin sensitive Staphylococcus aureus (MSSA) and 1.1% (n = 2) had methicillin resistant Staphylococcus aureus (MRSA). Status of viral hepatitis was 3.8% (n = 8), 10.8% (n = 20) for HBV and HCV respectively. Forty per cent (n = 8) of patients with HBV (+) had MSSA carrier status. Statistically significant positive correlation between MSSA and HCV carrier was detected (r = 0.325, p = 0.001) but not between HBV carrier and MSSA (p = 0.255). CONCLUSION: In the present study, significant positivity was detected between MSSA carrier status and HCV in patients on haemodialysis and who have lived together with < or = 2 family members at home. Particularly, statistically significant correlation between HCV(+) and MSSA carrier was observed.


Asunto(s)
Portador Sano/microbiología , Hepatitis B/microbiología , Hepatitis C/microbiología , Cavidad Nasal/microbiología , Diálisis Renal , Staphylococcus aureus/aislamiento & purificación , Anciano , Femenino , Hepatitis B/complicaciones , Hepatitis C/complicaciones , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Persona de Mediana Edad , Factores Socioeconómicos
15.
Braz J Biol ; 84: e261849, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35544798

RESUMEN

Frequent outbreaks of avian influenza H9N2 virus in Pakistan revealed that this subtype has become endemic in the poultry industry and, besides economic losses, poses a threat to public health. The present study describes the molecular characterization and pathological alterations in naturally infected broiler chickens with the current H9N2 field strain and their phylogenomic dynamics. In this study, tissue samples (trachea, lung, kidney and intestine) from 100 commercial chicken flocks were collected from July 2018 to August 2019. Samples were subjected to molecular detection, phylogeny and subsequent pathological examination. The complete length of the HA gene was successfully amplified in five samples. Nucleotide sequencing revealed positive samples placed in a clade belonging to the B2 sub-lineage of the G1 genotype and categorized as LPAIV based on the amino acid sequence of the HA gene at the cleavage site (PAKSSR/G). Genetic analysis of the haemagglutinin (HA) gene revealed nt: 80.5%-99.5%; aa: 83.8%-98.9% homology to H9N2 strains reported previously from Pakistan, neighbouring countries, and (A/Quail/Hong Kong/G1/97). Gross lesions include a slight airsacculitis, mild hemorrhages, diffuse congestion and purulent exudate in tracheal mucosa, fibrinonecrotic cast in the trachea lumen and mild pulmonary congestion. Histopathological alterations include sloughing of epithelial cells and infiltration of inflammatory cells in the trachea, mononuclear cells (MNCs) infiltration, pulmonary congestion and exudate in the lumen of parabronchi, peritubular congestion in the kidneys with degeneration of tubular epithelial cells and degenerative changes in the intestinal villi epithelial cells and goblet cell hyperplasia. Immunohistochemistry analysis confirmed the presence of AIVH9N2 antigen in the trachea, lungs, kidney and intestine. Electron microscopy revealed ultrastructural changes in the trachea, including degenerated cilia, mitochondrial swelling and enlarged endoplasmic reticulum. Based on all essential analysis, the present study revealed the distribution of the H9N2 virus of G1 genotype in Punjab, Pakistan, with mild to moderate pathogenicity.


Asunto(s)
Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Animales , Pollos , Subtipo H9N2 del Virus de la Influenza A/genética , Gripe Aviar/epidemiología , Pakistán/epidemiología , Filogenia , Aves de Corral
16.
Curr Top Med Chem ; 22(13): 1046-1067, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34961445

RESUMEN

The rapid emergence of multidrug-resistant bacterial strains highlights the need for the development of new antimicrobial compounds/materials to address associated healthcare challenges. Meanwhile, the adverse side effects of conventional antibiotics on human health urge the development of new natural product-based antimicrobials to minimize the side effects. In this respect, we concisely review the recent scientific contributions to develop natural product-based nano-antibiotics. The focus of the review is on the use of flavonoids, peptides, and cationic biopolymer functionalized metal/metal oxide nanoparticles as efficient tools to hit the MDR bacterial strains. It summarizes the most recent aspects of the functionalized nanoparticles against various pathogenic bacterial strains for their minimal inhibitory concentrations and mechanism of action at the cellular and molecular levels. In the end, the future perspectives to materialize the in vivo applications of nano-antimicrobials are suggested based on the available research.


Asunto(s)
Antiinfecciosos , Productos Biológicos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Bacterias , Farmacorresistencia Bacteriana Múltiple , Humanos , Pruebas de Sensibilidad Microbiana
17.
J Phys Chem A ; 115(50): 14502-9, 2011 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-22044256

RESUMEN

Perdew-Wang proposed generalized gradient approximation (GGA) is used in conjunction with ultrasoft pseudopotential to investigate the structural, elastic constant, and vibrational properties of wurtzite GaN. The equilibrium lattice parameters, axial ratio, internal parameter, bulk modulus, and its pressure derivative are calculated. The effect of pressure on equilibrium lattice parameters, axial ratio, internal parameter (u), relative volume, and bond lengths parallel and perpendicular to the c-axis are discussed. At 52 GPa, the relative volume change is observed to be 17.8%, with an abrupt change in bond length. The calculated elastic constants are used to calculate the shear wave speeds in the [100] and [001] planes. The finite displacement method is employed to calculate phonon frequencies and the phonon density of states. The first- and second-order pressure derivative and volume dependent Gruneisen parameter (γ(j)) of zone-center phonon frequencies are discussed. These phonon calculations calculated at theoretical lattice constants agree well with existing literature.

18.
J Phys Chem A ; 115(24): 6622-8, 2011 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-21604728

RESUMEN

The ab initio pseudopotential (PP) method within the generalized gradient approximation (GGA) has been used to investigate the electronic, elastic constants, and optical properties of zinc-blende GaN. An underestimated band gap along with higher DOS and squeezed energy bands around the fermi level is obtained. The d-band effect is briefly discussed for electronic band structure calculations. With the help of elastic constants, acoustic wave speeds are calculated in [100], [110], and [111] planes. The dielectric constant, refractive index, and its pressure coefficient are well illustrated. The effect of hydrostatic pressure is explicated for all these properties. The results of the present study are evaluated with the existing experimental and first-principle calculations.

19.
Artículo en Inglés | MEDLINE | ID: mdl-34909685

RESUMEN

Nanotheranostics is an emerging frontier of personalized medicine research particularly for cancer, which is the second leading cause of death. Supramolecular aspects in theranostics are quite allured to achieve more regulation and controlled features. Supramolecular nanotheranostics architecture is focused on engineering of modular supramolecular assemblies benefitting from their mutable and stimuli-responsive properties which confer an ultimate potential for the fabrication of unified innovative nanomedicines with controlled features. Amalgamation of supramolecular approaches to nano-based features further equip the potential of designing novel approaches to overcome limitations seen by the conventional theranostic strategies, for curing even the lethal diseases and endowing personalized therapeutics with optimistic prognosis, endorsing their clinical translation. Among many potential nanocarriers for theranostics, lipid nanoparticles (LNPs) have shown various promising advances in theranostics and their formulation can be tailored for several applications. Despite the great advancement in cancer nanotheranostics, there are still many challenges that need to be highlighted to fill the literature gap. For this purpose, herein, we have presented a systematic overview on the subject and proposed LNPs as the potential material to manage cancer via non-invasive approaches by highlighting the use of supramolecular approaches to make them robust for cancer theranostics. We have concluded the review by entailing the future perspectives of lipid nanotheranostics towards clinical translation.

20.
Biol Methods Protoc ; 6(1): bpab010, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34084942

RESUMEN

Cotton production is seriously affected by the prevalent cotton leaf curl disease (CLCuD) that originated from Nigeria (Africa) to various parts of Asia including Pakistan, India, China and Philippines. Due to CLCuD, Pakistan suffers heavy losses approximately 2 billion USD per annum. Numerous reports showed that CLCuD is associated with multiple species of begomoviruses, alphasatellites and a single species of betasatellite, that is 'Cotton leaf curl Multan betasatellite' (CLCuMuB). The most prevalent form of CLCuD is the combination of 'Cotton leaf curl Kokhran virus'-Burewala strain (CLCuKoV-Bur) and CLCuMuB. Thus, the availability of an in-field assay for the timely detection of CLCuD is important for the control and management of the disease. In this study, a robust method using the loop-mediated isothermal amplification (LAMP) assay was developed for the detection of CLCuD. Multiple sets of six primers were designed based on the conserved regions of CLCuKoV-Bur and CLCuMuB-ßC1 genes. The results showed that the primer set targeting the CLCuMuB-ßC1 gene performed best when the LAMP assay was performed at 58°C using 100 ng of total plant tissue DNA as a template in a 25 µl reaction volume. The limit of detection for the assay was as low as 22 copies of total purified DNA template per reaction. This assay was further adapted to perform as a colorimetric and real-time LAMP assay which proved to be advantageously applied for the rapid and early point-of-care detection of CLCuD in the field. Application of the assay could help to prevent the huge economic losses caused by the disease and contribute to the socio-economic development of underdeveloped countries.

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