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1.
Nanotechnology ; 34(21)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36807225

RESUMO

A substrate for surface-enhanced Raman spectroscopy (SERS) in a sandwich configuration, noble metal/analyte/defect-rich metal oxide, is demonstrated for the detection of methylene blue(MB). The sandwich structure (Ag/MB/SUMoO3) is fabricated by physical vapour deposition of Ag nanoparticles over the MB analytes that are adsorbed on sea urchin MoO3(SUMoO3). SUMoO3are grown on a glass substrate by chemical bath deposition. The morphology of the fabricated sandwich structures shows serrated spikes of MoO3from the core region decorated with strings of silver nanoparticles. The silver-decoration and the oxygen defects of SUMoO3promote absorption in the visible region and facilitate charge transfer between MB and SUMoO3, which are beneficial for achieving superior SERS properties in this configuration compared to the contribution from individual components alone. The sandwich structure is able to detect the MB molecule up to 100 nM with an enhancement factor of 8.1 × 106. The relative standard deviation of SERS intensity for the 1618 cm-1peak of MB across the substrate is 29.2%. The configuration offers stability to SERS substrate under ambient conditions. The combined effect of charge transfer, surface plasmon resonance, and MB resonance results in the improved SERS detection of MB molecules with the Ag/MB/SUMoO3sandwich structure.

2.
Cureus ; 14(2): e22253, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35350487

RESUMO

Background The present study assessed the efficacy of the residential, group-based, intensive holistic lifestyle intervention on glycaemic control. Materials and methods A one-group pre and post-intervention study was conducted among 145 people with diabetes for a period of one year from February 2019 to January 2020. The study population underwent "Brahma Kumaris Raja Yoga lifestyle" intervention. Outcome variables were changes in HbA1c levels and anthropometric parameters (like weight, BMI, etc.). Paired t-test was used to compare normally distributed numeric variables. Results The mean age was 52.39±5.79 years, with a male-female ratio close to 1:1. Mean HbA1c at baseline was 9.06±2.1%. The mean weight and BMI were 71.03±12.84 kg and 28.28±4.83kg/m2, respectively. Mean HbA1c value had shown a reduction of 1.60% (95%CI 1.17 to 1.90, p <0.001) at three months and 1.58% (95% CI 1.13-1.87, p<0.001) reduction at a six-month follow-up. Between the third and sixth months, there was no significant change in the HbA1c value. Mean weight reduced by 0.79 kg (95% CI 0.08-1.08, p=0.023) at six-month follow-up and mean BMI decreased by 0.31 units from baseline to three months (95% CI 0.05-0.56, p=0.017). A statistically significant reduction was observed in waist circumference at the third month (MD=1.61 95% CI =0.95 to 2.28, P<0.001) and sixth month (MD=1.53, 95% CI 0.82-2.25, p<0.001) follow-up. Conclusion This residential, group-based, intensive holistic lifestyle intervention showed a significant decrease in HbA1c levels and anthropometric parameters at three- and six-months follow-up, thereby improving the overall health and wellbeing of people with diabetes.

3.
Langmuir ; 36(26): 7332-7344, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32510224

RESUMO

The rapid, ultralow detection, degradation, and complete removal of pesticides demand the design of potential substrates. Herein, we discussed gold nanorods (Au NRs) as the potential substrate for the naked eye detection and degradation of two common and broad-spectrum pesticides, chlorpyrifos (CPF) and malathion (MLT), up to 0.15 ppt concentration within 2 min. Under certain environmental conditions, both the pesticides degraded and adsorbed on the surface of Au NRs. The degraded moieties of CPF and MLT on the surface of Au NRs formed side-to-side and end-to-end interactions, respectively, leading to a long-range assembly. This shows that no external agent is required, and only CPF and MLT analytes are quite enough for the formation of assembly of Au NRs. Assembly of Au NRs is confirmed by transmission electron microscopy (TEM) analysis, and degradation is supported by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and gas chromatography-mass spectrometry (GC-MS) analyses. Au NRs were recovered and reused for four consecutive cycles. The fast and ultralow detection of pesticides demonstrates that Au NRs are a potential substrate for the detection and degradation of pesticides.

4.
Geroscience ; 42(1): 271-285, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31786733

RESUMO

Wild-type Canton-S flies of Drosophila melanogaster were treated with ellagic acid at 100 µM and 200 µM concentrations. Longevity assay showed male flies fed with 200 µM ellagic acid displayed longer mean lifespan and maximum lifespan than control flies. Female flies fed with 200 µM ellagic acid laid less number of eggs than control. The eclosion time was less in female flies fed with 200 µM ellagic acid. Ellagic acid fed female flies performed better than male flies and control flies for heat shock tolerance and starvation stress. Male flies treated with 100 µM ellagic acid recovered faster from cold shock compared with control flies. Male and female flies treated with ellagic acid displayed increased survival following exposure to 5% hydrogen peroxide. Gene expression studies displayed upregulated expressions of CAT, dFOXO, ATG1, and SOD2 in ellagic acid-treated male flies, and upregulated expressions of dFOXO, CAT, and SOD2 in ellagic acid-treated female flies. Results from these studies show the pro-longevity effect of ellagic acid on Drosophila melanogaster.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Animais , Proteínas de Drosophila/genética , Ácido Elágico/farmacologia , Feminino , Peróxido de Hidrogênio , Longevidade , Masculino
5.
ACS Omega ; 4(11): 14569-14578, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31528811

RESUMO

Tribological studies of the 2D nanoadditives such as MoS2 and graphene are mostly performed in base oils such as SN500, SN150, or paraffin. We have focused on their effect in lubrication properties of industrial oils (e.g., axle, transmission, and compressor oils) along with SN500 oil employing a four-ball tester. Two types of graphene powders (GpowA with fewer defects than GpowC), MoS2 powder, and their physical mixtures are chosen as nanoadditives. The tribology performance for 0.05 wt% of additives in various industrial oils is evaluated by monitoring the coefficient of friction (COF) during rubbing and wear scar diameter (WSD) of the steel balls after rubbing. Elemental analysis and electron microscopy have been performed on the wear surfaces for evidence of any tribofilm formation. GpowA favors antifriction for axle and transmission oils with 40% reduction in axle oil, whereas it improved antiwear properties in most of the oils. GpowC shows a COF decrement by 12% only for compressor oil, but contribute to wear reduction in all oils. The observed COF reduction is attributed to the compatibility of nonfunctionalized GpowA with nonpolar axle oil and functionalized GpowC with polar compressor oil. MoS2 shows a decrease in the COF and WSD in most industrial oils; the best being 60% COF and 7% WSD reduction in axle oil. For additives in oils that favor antiwear, flakes or particles are observed on the wear surface supported by the higher elemental contribution of the constituents from the wear region. The mixtures of GpowA or C with MoS2, however, does not seem to favor improvement in the COF or WSD in industrial oils. With assistance from oleylamine surfactants, the lubrication properties of most additives are improved, particularly for the mixtures with 12-15% COF reduction and 4-7% WSD reduction in compressor oil. The study indicates that a large sheet size of high-quality graphene aids antifriction and addition of surfactant molecules facilitates a co-operative effect between MoS2 and graphene for improved tribology.

6.
Nanoscale Adv ; 1(6): 2426-2434, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-36131958

RESUMO

Enhancing the surface-enhanced Raman scattering (SERS) activity of semiconductor metal oxide nanostructures by controlling the morphology and oxygen vacancies towards trace detection of organics is of significant interest. In this study, MoO3 with a novel sea urchin morphology is synthesized employing chemical bath deposition and consists of hundreds of ∼15 µm long spikes originating from the core forming 20-40 micron globular structures. The spikes taper to form 20 nm sharp tips. SERS of rhodamine 6G (R6G) over MoO3 sea urchins has been investigated and compared to that of 1D h-MoO3 nanorod arrays. The SERS activity is morphology dependent and the sea urchin-like morphology exhibits higher SERS activity with an enhancement factor (EF) of the order 105 and a detection limit of 100 nM, while for h-MoO3 nanorods, the corresponding values are 103 and 1 µM, respectively. X-ray photoelectron spectroscopy reveals a high concentration of Mo+5 states in sea urchins indicating lattice oxygen vacancies. The observed EF is quite high for a metal oxide substrate and is attributed to the enhanced charge transfer between analyte molecules and the substrate promoted by the oxygen vacancies along with surface defects and hydroxyl groups on MoO3 sea urchins providing more active sites for the adsorption of probe molecules. The role of oxygen vacancies is confirmed by the lower EF value exhibited by the stoichiometric 1D h-MoO3. Raman mapping of a single sea urchin is achieved with good R6G intensity and indicates that the tips of spiky features are involved in SERS enhancement. The reusability of substrates is shown for repeated cycles of R6G adsorption by UV irradiation exploiting the photocatalytic activity of MoO3 nanostructures.

7.
J Clin Diagn Res ; 7(12): 3094-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24551740

RESUMO

Amyloid involvement of the tongue is almost always secondary to systemic amyloidosis. Isolated amyloidosis of the tongue is relatively rare and it accounts for less than 9% of all types of amyloidosis. We are presenting a case of a 54-year-old male patient who complained of an enlarged tongue and bilateral multiple swellings on the lateral borders of the tongue, which had been there since one year. Bilaterally symmetrical, violaceous, purpuric patches interspersed with nodules were seen surrounding the eyes. Histopathologically, the lesion exhibited homogenous eosinophilic amyloid-like material. Special staining with Congo red showed amyloid material as peach red colour under light microscopy and as apple green birefringence under polarized light. Based on these observations, a definitive diagnosis of amyloidosis of tongue was made. Amyloidosis of tongue is uncommon and its features resemble those of a benign tumour. A battery of tests is necessary to differentiate localized amyloidosis from its systemic forms.

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