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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 325: 125124, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39303335

RESUMEN

The escalating concern regarding the adverse effects of metal ion toxicity on both human health and environmental ecosystems necessitates the development of efficient detection methodologies. This study presents a focused investigation on the selective and sensitive detection of Cu(II) ions employing hybrid magnetic nanoparticles derived from chalcone-based bis-organosilane. These nanoparticles exhibit a notably low detection limit in the nano-scale range, rendering the sensor highly sensitive to Copper(II) ion detection while maintaining robust anti-interference capabilities, even in the presence of diverse metal ions. Real sample analysis confirms the sensor's efficacy in detecting Cu(II) ions below WHO-prescribed levels. Computational analyses reveal molecular interactions and biological activities, including potent antibacterial and antioxidant properties, suggesting promising applications. Furthermore, the biological effectiveness of chalcone-derived bis-organosilane is investigated, unveiling notable antibacterial efficacy and also exhibiting potential as a scavenger of free radicals, indicating promising applications in both antibacterial and antioxidant domains.

2.
RSC Adv ; 14(22): 15374-15390, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38741961

RESUMEN

In this study, two novel chalcone-derived 1,2,3-triazole-appended positional isomers (probe 6 and probe 9) were synthesized via the 'CuAAC' (Cu(i) - catalysed alkyne azide cycloaddition) methodology for the purpose of metal ion detection. The synthesized probes underwent characterization utilizing standard spectroscopic methodologies including FTIR, NMR (1H and 13C), and mass spectrometry. Subsequently, the sensing capabilities of these probes were explored using UV-Vis and fluorescence spectroscopy, wherein their selective recognition potential was established for Pb(ii) and Cu(ii), both of which can pose serious health hazards when prevalent in the environment above permissible limits. Both the probes exhibited fairly low limits of detection (LoD), determined as 5.69 µM and 6.55 µM in the case of probe 6 for Pb(ii) and Cu(ii) respectively; whereas the probe 9 exhibited an LoD of 5.06 µM and 7.52 µM for Pb(ii) and Cu(ii), respectively. The job's plot for the probe demonstrates the formation of a 1 : 1 complex between the metal and ligand. Furthermore, the interaction of the free probes with the metal ions in the metal-ligand complex was elucidated through 1H NMR analysis and validated theoretically using Density Functional Theory (DFT) simulations with the B3LYP/6-311G++(d,p) and B3LYP/LANL2DZ basis sets for geometry optimization of the probes and their corresponding metal complexes. These findings offer a reliable approach to Cu(ii) and Pb(ii) ion detection and can be further used for the potential applications in environmental monitoring and analytical chemistry.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 299: 122854, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37196553

RESUMEN

The development of a ligand for their selective and sensitive detection is required due to the widespread use of Cu2+ in many industrial processes and the potential threat to human health. Herein, we report a bis-triazole linked organosilane (5) derived from the Cu(I) catalyzed azide-alkyne cycloaddition reaction. The synthesized compound 5 was characterized by (1H and 13C) NMR spectroscopic and mass spectrometry techniques. The UV-Visible and Fluorescence experiments of the designed compound 5 were performed with various metal ions, revealing its high selectivity and sensitivity to Cu2+ ions in MeOH: H2O (8:2, v/v, pH = 7.0, PBS buffer) solution. The selective fluorescence quenching upon addition of Cu2+ to the compound 5 is due to Photo-induced electron transfer process (PET). The limit of detection of compound 5 to Cu2+ was calculated as 2.56 × 10-6 M and 4.36 × 10-7 M through UV-Visible and Fluorescence titration data, respectively. The possible mechanism of 1:1 binding of 5 with Cu2+ could be affirmed by the density functional theory (DFT). Further, it was found that compound 5 showed a reversible behavior towards Cu2+ ions by the accumulation of sodium salt of CH3COO- which can be used in the construction of molecular logic gate where Cu2+ and CH3COO- are considered as inputs and the absorbance at 260 nm as output. Moreover, the molecular docking studies provide useful information about compound 5's interaction with the tyrosinase enzyme (PDB ID- 2Y9X).


Asunto(s)
Colorantes Fluorescentes , Compuestos de Organosilicio , Humanos , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia/métodos , Monofenol Monooxigenasa , Simulación del Acoplamiento Molecular , Triazoles , Iones/análisis
4.
Mol Biotechnol ; 65(9): 1432-1443, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36637627

RESUMEN

Group A rotavirus causes acute gastroenteritis in young ones of animals worldwide and is responsible for a high rate of their morbidity and mortality leading to huge economic losses. Developing affordable and safer vaccine on large scale is imperative to reach cattle population worldwide for the long-term control of diarrhea. Rotavirus middle capsid protein layer, VP6, is the most immunogenic and highly conserved protein that induces immune responses against rotavirus. In the present study, bovine group A rotavirus VP6 protein has been expressed for the first time in a highly nutritious and palatable forage crop, Trifolium alexandrinum, using Agrobacterium tumefaciens-mediated stable nuclear transformation. Transgenic nature of the shoots regenerated from cotyledon explants and rooted on hygromycin-containing medium was confirmed by polymerase chain reaction (PCR), Southern blot hybridization, reverse transcription-PCR (RT-PCR) and quantitative real-time PCR (qPCR), and protein expression and quantification by Western blot and enzyme-linked immune-sorbent assay (ELISA), respectively. The transformation efficiency of 2.10% was obtained. The highest amount of VP6 protein produced in a transgenic line was 402 ng/g fresh weights (0.03% of total soluble protein). Oral feeding of transgenic leafy shoots expressing VP6 protein stimulated systemic immunity by inducing significantly higher titers of anti-VP6 serum IgG antibodies in rabbit to reduce rotavirus infection. These transgenic fodder plants offer safer vaccine produced on large scale at low cost with reduced regulatory issues to improve livestock's health and wealth. These plants would be used as alternative to the current live attenuated vaccines to protect young calves against rotavirus infection.


Asunto(s)
Infecciones por Rotavirus , Vacunas contra Rotavirus , Rotavirus , Trifolium , Animales , Bovinos , Conejos , Rotavirus/genética , Infecciones por Rotavirus/prevención & control , Infecciones por Rotavirus/veterinaria , Egipto , Anticuerpos Antivirales , Proteínas de la Cápside/genética , Antígenos Virales , Vacunas de Subunidad , Inmunidad
5.
Sci Total Environ ; 858(Pt 2): 159594, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36280050

RESUMEN

The present study aims to produce nanocomposites of silica based organosilane as sensitive and selective fluorescent sensor for the recognition of 2,4 dichlorophenoxyacetic acid (2,4-D). Hydrazone tethered triazole functionalized organosilane has been synthesized by the condensation reaction of 4-hydroxybenzaldehyde and phenyl hydrazine followed by Cu(I) catalysed cycloaddition of azide with alkyne. The prepared compound has been further grafted over silica surface and the synthesized materials were characterized by FT-IR, NMR (1H and 13C), XRD, mass spectrometry and FE-SEM spectral analyses. The prepared organosilane and its HSNPs have been utilized as an effective emission probe for the selective detection of 2,4 D with good linear relationship in the range of 0-160 µM and 0-115 µM and LOD value of 46 nM and 13.5 nM respectively. In the presence of other active species, the sensor shows minimal interference while the comparison with the previously reported techniques suggests it to be more desirable for the sensitive and selective detection of 2,4 D. Further, the real sample application for detection of 2,4 D was analyzed in field water and the HSNPs based sensing system gave recovery percentage of above 98 %.


Asunto(s)
Herbicidas , Nanocompuestos , Compuestos de Organosilicio , Dióxido de Silicio/química , Espectroscopía Infrarroja por Transformada de Fourier , Herbicidas/análisis , Nanocompuestos/química , Ácido 2,4-Diclorofenoxiacético/análisis , Agua/química , Fenoxiacetatos
6.
Nature ; 607(7917): 69-73, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35794269

RESUMEN

Quantum networks promise to provide the infrastructure for many disruptive applications, such as efficient long-distance quantum communication and distributed quantum computing1,2. Central to these networks is the ability to distribute entanglement between distant nodes using photonic channels. Initially developed for quantum teleportation3,4 and loophole-free tests of Bell's inequality5,6, recently, entanglement distribution has also been achieved over telecom fibres and analysed retrospectively7,8. Yet, to fully use entanglement over long-distance quantum network links it is mandatory to know it is available at the nodes before the entangled state decays. Here we demonstrate heralded entanglement between two independently trapped single rubidium atoms generated over fibre links with a length up to 33 km. For this, we generate atom-photon entanglement in two nodes located in buildings 400 m line-of-sight apart and to overcome high-attenuation losses in the fibres convert the photons to telecom wavelength using polarization-preserving quantum frequency conversion9. The long fibres guide the photons to a Bell-state measurement setup in which a successful photonic projection measurement heralds the entanglement of the atoms10. Our results show the feasibility of entanglement distribution over telecom fibre links useful, for example, for device-independent quantum key distribution11-13 and quantum repeater protocols. The presented work represents an important step towards the realization of large-scale quantum network links.

7.
Case Rep Dent ; 2013: 845405, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24222867

RESUMEN

Filippi syndrome is an autosomal recessive condition characterized by variable soft tissue syndactyly of the fingers and toes, microcephaly, pre- and postnatal growth retardation, mildly abnormal craniofacial appearance, and mental retardation. We report on a child with Filippi syndrome who shows syndactyly of fingers, severe postnatal growth retardation, postnatal microcephaly, and moderate to severe mental retardation. In addition, there is a mildly dysmorphic face along with ocular and a number of dental abnormalities. Radiologically, hands demonstrate bony syndactyly, without any hypoplasia of bones. This phenotype can easily be classified in the group of craniodigital syndromes, but it is difficult to make a more clearly defined diagnosis, based on other minor anomalies, because of the presence of overlapping features. On the basis of various pathognomic features, we conclude that our patient could be an additional case of Filippi syndrome. Moreover, newly recognised features in this patient may be due to variability in phenotypic expression.

8.
Int J Clin Pediatr Dent ; 5(1): 14-9, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25206128

RESUMEN

AIM: The purpose of this study was to assess skeletal age and establish relationship between mandibular canine calcification and skeletal age. MATERIALS AND METHODS: The study included 147 females aged 10 to 13 years. The subjects were divided into three groups: Group I-comprising of 10 to 11 years old female; Group II-comprising of 11 to 12 years old female; Group III-12 to 13 years female. OPG and hand and wrist radiographs of left side for each subject were taken with prior consent of their parents. The calcification status of canine was evaluated from orthopantomograms according to scores given in Demirjian's method. The stages of ossification of various carpal bones were evaluated using radiographic atlas of Greulich-Pyle and skeletal age was calculated. RESULTS: Data collected was statistically analyzed. CONCLUSION: The results drawn from this study showed that a strong correlation was observed for canine calcification stage F for 10 to 11 years and for stage G in 11 to 12 years and 12 to 13 years respectively. How to cite this article: Malik P, Rana V, Rehani U. To Evaluate the Relationship between Mandibular Canine Calcification Stages and Skeletal Age. Int J Clin Pediatr Dent 2012;5(1): 14-19.

9.
Int J Clin Pediatr Dent ; 3(3): 207-10, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-27616845

RESUMEN

Osteopetrosis is a rare metabolic disease.(1) Dental abnormalities may be attributed to the pathological changes in osteopetrosis. Patients with osteopetrosis are especially susceptible to osteomyelitis of mandible.(1) A 13-year-old girl presented with complaint of jaw swelling on left side. The radiograph of left mandible (lateral oblique view) showed small sequestrum with irregularity and erosions of the man-dibular cortical margins. This case report aims at diagnosis and treatment of osteopetrosis with superadded mandibular osteomyelitis-a are entity.

10.
Lancet Infect Dis ; 6(6): 374-82, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16728323

RESUMEN

To evaluate the evidence for the use of probiotics in the prevention of acute diarrhoea, we did a meta-analysis of the available data from 34 masked, randomised, placebo-controlled trials. Only one trial was community based and carried out in a developing country. Most of the remaining 33 studies were carried out in a developed country in a health-care setting. Evaluating the evidence by types of acute diarrhoea suggests that probiotics significantly reduced antibiotic-associated diarrhoea by 52% (95% CI 35-65%), reduced the risk of travellers' diarrhoea by 8% (-6 to 21%), and that of acute diarrhoea of diverse causes by 34% (8-53%). Probiotics reduced the associated risk of acute diarrhoea among children by 57% (35-71%), and by 26% (7-49%) among adults. The protective effect did not vary significantly among the probiotic strains Saccharomyces boulardii, Lactobacillus rhamnosus GG, Lactobacillus acidophilus, Lactobacillus bulgaricus, and other strains used alone or in combinations of two or more strains. Although there is some suggestion that probiotics may be efficacious in preventing acute diarrhoea, there is a lack of data from community-based trials and from developing countries evaluating the effect on acute diarrhoea unrelated to antibiotic usage. The effect on acute diarrhoea is dependent on the age of the host and genera of strain used.


Asunto(s)
Diarrea/prevención & control , Probióticos/uso terapéutico , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Humanos , Lactobacillus/crecimiento & desarrollo , Probióticos/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto , Saccharomyces/crecimiento & desarrollo
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