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1.
Opt Express ; 32(4): 6597-6608, 2024 Feb 12.
Article En | MEDLINE | ID: mdl-38439359

High temporal resolution is essential for ultra-fast pump-probe experiments. Arrival time jitter and drift measurements, as well as their control, become critical especially when combining XUV or X-ray free-electron lasers (FELs) with optical lasers due to the large scale of such facilities and their distinct pulse generation processes. This paper presents the application of a laser pulse arrival time monitor that actively corrects the arrival time of an optical laser relative to the FEL's main optical clock. Combined with post-analysis single pulse jitter correction this new approach improves the temporal resolution for pump-probe experiments significantly. Benchmark measurements on photo-ionization of xenon atoms performed at FLASH beamline FL26, demonstrate a sub-50 fs FWHM overall temporal resolution.

2.
Adv Sci (Weinh) ; 11(12): e2306586, 2024 Mar.
Article En | MEDLINE | ID: mdl-38225711

Caged compounds are frequently used in life science research. However, the light used to activate them is commonly absorbed and scattered by biological materials, limiting their use to basic research in cells or small animals. In contrast, hard X-rays exhibit high bio-permeability due to the difficulty of interacting with biological molecules. With the main goal of developing X-ray activatable caged compounds, azo compounds are designed and synthesized with a positive charge and long π-conjugated system to increase the reaction efficiency with hydrated electrons. The azo bonds in the designed compounds are selectively cleaved by X-ray, and the fluorescent substance Diethyl Rhodamine is released. Based on the results of experiments and quantum chemical calculations, azo bond cleavage is assumed to occur via a two-step process: a two-electron reduction of the azo bond followed by N─N bond cleavage. Cellular experiments also demonstrate that the azo bonds can be cleaved intracellularly. Thus, caged compounds that can be activated by an azo bond cleavage reaction promoted by X-ray are successfully generated.

4.
Acc Chem Res ; 56(23): 3404-3416, 2023 Dec 05.
Article En | MEDLINE | ID: mdl-37956385

ConspectusClimate change poses unprecedented challenges, demanding efforts toward innovative solutions. Amid these efforts, chemical looping stands out as a promising strategy, attracting attention for its CO2 capture prowess and versatile applications. The chemical looping approach involves fragmenting a single reaction, often a redox reaction, into multiple subreactions facilitated by a carrier, frequently a metal oxide. This innovative method enables diverse chemical transformations while inherently segregating products, enhancing process flexibility, and fostering autothermal properties. An intriguing facet of this novel technique lies in its capacity for CO2 utilization in processes like dry reforming and gasification of carbon-based feeds such as natural gas and biomass. Central to the success of chemical looping technology is a profound understanding of the intricacies of redox chemistry within these processes. Notably, nanoscaled oxygen carriers have proven effective, characterized by their extensive surface area and customizable structure. These carriers hold substantial promise, enabling reactions under milder conditions.This Account offers a concise overview of the mechanisms, benefits, opportunities, and challenges associated with nanoscaled carriers in chemical looping applications, with a focus on CO2 utilization. We delve into the nuances of redox chemistry, shedding light on ionic diffusion and oxygen vacancy─two key elements that are crucial in designing oxygen carriers. This discussion extends to nanospecific factors such as the particle size effect and gas diffusivity. Through the application of density functional theory simulations, insights are drawn regarding the impact of nanoparticle size on syngas production in chemical looping. Interestingly, nanosized iron oxide (Fe2O3) carriers exhibit elevated syngas selectivity and constrained CO2 formation at the nanoscale. Moreover, the reactivity enhancement of mesoporous SBA-16 supported Fe2O3 over mesoporous SBA-15 supported Fe2O3 is elucidated through Monte Carlo simulations that emphasize the superiority of the 3-dimensional interconnected porous network of SBA-16 in enhancing gas diffusion, thereby amplifying reactivity compared to the 2-dimensional SBA-15. Furthermore, we explore prevalent nanoscaled carriers, focusing on their amplified performance in CO2 utilization schemes. These encompass the integration of nanoparticles with mesoporous supports to enhance surface area, the adoption of nanoscale core-shell architectures to enhance diffusion, and the dispersion of nanoscaled active sites on microsized carriers to accelerate reactant activation. Notably, our mesoporous-supported Fe2O3 nanocarrier facilitates methane dissociation and oxidation by reducing energy barriers, thereby promoting methane conversion. The Account proceeds to outline key challenges and prospects for nanoscaled carriers in chemical looping, concluding with a glance into future research directions. We also shine a spotlight on our research group's efforts in innovating oxygen carrier materials, supplemented by discussions on indispensable elements that are essential for successful scale-up deployment.

5.
Sci Adv ; 9(44): eadi8500, 2023 Nov 03.
Article En | MEDLINE | ID: mdl-37910611

The topological phase revolutionized wave transport, enabling integrated photonic interconnects with sharp light bending on a chip. However, the persistent challenge of momentum mismatch during intermedium topological mode transitions due to material impedance inconsistency remains. We present a 100-Gbps topological wireless communication link using integrated photonic devices that conserve valley momentum. The valley-conserved silicon topological waveguide antenna achieves a 12.2-dBi gain, constant group delay across a 30-GHz bandwidth and enables active beam steering within a 36° angular range. The complementary metal oxide semiconductor-compatible valley-conserved devices represent a major milestone in hybrid electronic-photonic-based topological wireless communications, enabling terabit-per-second backhaul communication, high throughput, and intermedium transport of information carriers, vital for the future of communication from the sixth to X generation.

6.
Cancer Cell Int ; 23(1): 236, 2023 Oct 11.
Article En | MEDLINE | ID: mdl-37821962

BACKGROUND: Breast cancer (BC) is the most common malignancy with very high incidence and relatively high mortality in women. The PIK3CA gene plays a pivotal role in the pathogenicity of breast cancer. Despite this, the mutational status of all exons except exons 9 and 20 still remains unknown. METHODS: This study uses the whole exome sequencing (WES) based approach to identify somatic PIK3CA mutations in Indian BC cohorts. The resultant hotspot mutations were validated by droplet digital PCR (ddPCR). Further, molecular dynamics (MD) simulation was applied to elucidate the conformational and functional effects of hotspot position on PIK3CA protein. RESULTS: In our cohort, PIK3CA showed a 44.4% somatic mutation rate and was among the top mutated genes. The mutations of PIK3CA were confined in Exons 5, 9, 11, 18, and 20, whereas the maximum number of mutations lies within exons 9 and 20. A total of 9 variants were found in our study, of which 2 were novel mutations observed on exons 9 (p.H554L) and 11 (p.S629P). However, H1047R was the hotspot mutation at exon 20 (20%). In tumor tissues, there was a considerable difference between copy number of wild-type and H1047R mutant was detected by ddPCR. Significant structural and conformational changes were observed during MD simulation, induced due to point mutation at H1047R/L position. CONCLUSIONS: The current study provides a comprehensive view of novel as well as reported single nucleotide variants (SNVs) in PIK3CA gene associated with Indian breast cancer cases. The mutation status of H1047R/L could serve as a prognostic value in terms of selecting targeted therapy in BC.

7.
bioRxiv ; 2023 Oct 19.
Article En | MEDLINE | ID: mdl-37905113

We present a novel quantitative immunoassay for CD63 EVs (extracellular vesicles) and a constituent surface cargo, EGFR and its activity state, that provides a sensitive, selective, fluorophore-free and rapid alternative to current EV-based diagnostic methods. Our sensing design utilizes a charge-gating strategy, with a hydrophilic anion exchange membrane and a charged silica nanoparticle reporter. With sensitivity and robustness enhancement by the ion-depletion action of the membrane, this hydrophilic design with charged reporters minimizes interference from dispersed proteins and fluorophore degradation, thus enabling direct plasma analysis. With a limit of detection of 30 EVs/µL and a high relative sensitivity of 0.01% for targeted proteomic subfractions, our assay enables accurate quantification of the EV marker, CD63, with colocalized EGFR by an operator/sample insensitive universal normalized calibration. Glioblastoma necessitates improved non-invasive diagnostic approaches for early detection and monitoring. Notably, we target both total and "active" EGFR on EVs; with a monoclonal antibody mAb806 that recognizes a normally hidden epitope on overexpressed or mutant variant III EGFR. This approach offers direct glioblastoma detection from untreated human patient samples. Analysis of glioblastoma clinical samples yielded an area-under-the-curve (AUC) value of 0.99 and low p-value of 0.000033, significantly surpassing the performance of existing assays and markers.

8.
Heliyon ; 9(9): e20345, 2023 Sep.
Article En | MEDLINE | ID: mdl-37809659

Objective: To evaluate the surgical visual outcomes of three-piece rigid scleral fixated intraocular lens (SFIOL) implantation in subjects with deficient posterior capsule following complications of cataract extraction. Design: Retrospective 4-year cohort study. Participants: Data from 174 eyes that underwent SFIOL combined with pars plana vitrectomy (PPV) between January 2018 and March 2022 and follow-up exams were included. Methods: Demographic characteristics including primary indications for surgery, history of trauma, laterality, baseline and best-corrected visual acuity (BCVA), refraction as spherical equivalent (SE), intraocular pressure (IOP), duration of follow-up, and complications were analyzed. Results: The mean preoperative BCVA was 1.38 ± 0.46 logarithm of the minimum angle of resolution (logMAR), which improved significantly to 0.37 ± 0.22 logMAR. The baseline refractive status measured in spherical equivalent (SE) was 4.1 ± 6.2 Diopters (D), and the postoperative status was -0.4 ± 0.97 D. Early postoperative complications included hypotony (n = 1; 0.57%, vitreous hemorrhage (n = 3; 1.72%), elevated IOP (n = 8; 4.59%), mild dilated pupil (n = 1; 0.57%) and corneal edema (n = 16; 9.19%). Late complications included in this study were retinal detachment (n = 1; 0.57%), cystoid macular edema (CME) (n = 1; 0.57%), primary glaucoma (n = 1; 0.57%), secondary glaucoma (n = 13; 7.47%), zonular dehiscence (n = 3; 1.72%), retinal pigment epithelium (RPE) changes (n = 3; 1.72%), choroidal coloboma (n = 2; 1.14%), posterior dislocation of posterior chamber IOL (PCIOL) (n = 1; 0.57%), corneal decompensation (n = 1; 0.57%), retinal hemorrhage (n = 1; 0.57%), macular hole (n = 1; 0.57%), chronic uveitis (n = 1; 0.57%), mild non-proliferative diabetic retinopathy (NPDR) (n = 3; 1.72%), and mild NPDR with diabetic macular edema (DME) (n = 1; 0.57%). Conclusion: Integrating IOL implantation with vitrectomy various posterior segment complications were resolved in the same setting without attempting a second surgery.

9.
Front Genet ; 14: 1235260, 2023.
Article En | MEDLINE | ID: mdl-37593116

Background: Hepatitis B virus (HBV) infection is one of the major causes of chronic liver disease, which progresses from chronic hepatitis B (CHB) to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Early detection and laboratory-based screening of hepatocellular carcinoma are still major challenges. This study was undertaken to determine whether the cancer hallmark gene signatures that are released into circulation as circulating tumour DNA (ctDNA) can be used as a liquid biopsy marker for screening, early detection, and prognosis of HCC. Methods: A total of 130 subjects, including HBV-HCC (n = 80), HBV-cirrhotic and non-cirrhotic (n = 35), and healthy (n = 15) controls, were evaluated for TP53 and beta-catenin (CTNNB1) gene hotspot mutations in ctDNA by Sanger-based cycle sequencing and droplet digital PCR (ddPCR) assays. Mutation detection frequency, percentage mutant fractions, and their association with tumour stage, mortality, and smoking habits were determined. Results: Sanger-based cycle sequencing was carried out for 32 HCC patients. Predict SNP Tools analysis indicated several pathogenic driver mutations in the ctDNA sequence, which include p.D228N, p.C229R, p.H233R, p.Y234D, p.S240T, p.G245S, and p.R249M for TP53 gene exon 7 and p.S33T for CTNNB1 gene exon 3. The TP53 c.746G>T (p.R249M) mutation was detected predominately (25% cases) by sequencing, but there was no dominant mutation at position c.747G>T (p.R249S) that was reported for HBV-HCC patients. A dual-probe ddPCR assay was developed to determine mutant and wild-type copy numbers of TP53 (p.R249M and p.R249S) and CTNNB1 (p.S45P) and their percentage mutant fraction in all 130 subjects. The TP53 R249M and CTNNB1 S45P mutations were detected in 31.25% and 26.25% of HCC patients, respectively, with a high mutant-to-wild-type fraction percentage (1.81% and 1.73%), which is significant as compared to cirrhotic and non-cirrhotic patients. Poor survival was observed in HCC patients with combined TP53 and CTNNB1 gene driver mutations. The TP53 R249M mutation was also significantly (p < 0.0001) associated with smoking habits (OR, 11.77; 95% CI, 3.219-36.20), but not the same for the TP53 R249S mutation. Conclusion: Screening of ctDNA TP53 and CTNNB1 gene mutations by ddPCR may be helpful for early detection and identifying the risk of HCC progression.

10.
J Phys Chem Lett ; 14(31): 7126-7133, 2023 Aug 10.
Article En | MEDLINE | ID: mdl-37534743

Recent developments in X-ray free-electron lasers have enabled a novel site-selective probe of coupled nuclear and electronic dynamics in photoexcited molecules, time-resolved X-ray photoelectron spectroscopy (TRXPS). We present results from a joint experimental and theoretical TRXPS study of the well-characterized ultraviolet photodissociation of CS2, a prototypical system for understanding non-adiabatic dynamics. These results demonstrate that the sulfur 2p binding energy is sensitive to changes in the nuclear structure following photoexcitation, which ultimately leads to dissociation into CS and S photoproducts. We are able to assign the main X-ray spectroscopic features to the CS and S products via comparison to a first-principles determination of the TRXPS based on ab initio multiple-spawning simulations. Our results demonstrate the use of TRXPS as a local probe of complex ultrafast photodissociation dynamics involving multimodal vibrational coupling, nonradiative transitions between electronic states, and multiple final product channels.

11.
Cureus ; 15(7): e41495, 2023 Jul.
Article En | MEDLINE | ID: mdl-37551235

Background Dementia is an age-related gradual loss of memory that is progressive in nature. Presently, the most common cause of dementia is Alzheimer's disease (AD), which is treated with donepezil, an anticholinesterase. But it only provides short-term symptomatic improvement. Liraglutide, which is an anti-diabetic drug, stimulates the anti-apoptotic pathway of nerve damage, which helps in regenerating nerve cells; so, it may help in dementia cases. Therefore, this study aimed to explore the effect of liraglutide on learning and memory and to compare its effect with donepezil in diazepam-induced amnesic albino rats. Methodology Twenty healthy male Albino rats weighing 150-200 grams were taken and divided into four groups: A, B, C, and D. Group A rats were normal rats, whereas the rats in groups B, C, and D were made amnesic by the intraperitoneal (i.p.) administration of 0.1 mg per kg of diazepam. Immediately after producing amnesia, group B rats received normal saline, group C received liraglutide, and group D received donepezil through the intraperitoneal route as test drugs. Group A rats received only normal saline. The amnesic effect was measured by the escape latency period, which was measured by using a Morris Water Maize (MWM) instrument. Escape latency is the time (in seconds) to locate the platform from the starting point. The amnesic effect is shown by an increase in escape latency and the anti-amnesic effect by a decrease in escape latency. Escape latency was recorded at 0 hr, 1 hr, 2 hr, 3 hr, and 4 hr after test drug administration. Results Group B rats showed an increase in escape latency, which shows the amnesic effect of diazepam. When group C and group D amnesic rats were treated with liraglutide and donepezil, respectively, a one-hour after-treatment increase in escape latency was seen but after two hours, both groups showed a decrease in escape latency, which indicates the anti-amnesic effect of both drugs. When groups C and D were compared, and the post-hoc highly significant difference (HSD) test was used, there was no significant difference between the two drugs, although the liraglutide-treated group (C) showed a lower anti-amnesic effect. However, group C showed a significant effect as compared to group B rats (p-value <0.05), which indicates the anti-amnesic property of liraglutide as compared to normal saline. Conclusion Liraglutide shows an anti-amnesic property. Since it works by a mechanism different from donepezil, it can be used as add-on therapy with donepezil in dementia patients.

12.
Life Sci ; 328: 121893, 2023 Sep 01.
Article En | MEDLINE | ID: mdl-37392778

Growing evidences suggest that excess generation of highly reactive free oxygen/nitrogen radicals (ROS/RNS) are largely due to hyperglycemia causes oxidative stress. Further, excess accumulation of ROS/RNS in cellular compartments aggravates the development and progression of diabetes and its associated complications. Impaired wound healing in diabetic condition is a known vital complication all around the world. Thus, an antioxidant agent having the potential for hindering the oxidative/nitrosative stress triggered diabetic skin complication is required. The present investigation was carried out to understand the impact of silica coated gold nanoparticle (Au@SiO2 NPs) on high glucose (HG)-induced keratinocyte complications. We demonstrated that HG environment enhanced the ROS and RNS accumulations and reduced in cellular antioxidant capacities in keratinocte cells, however, Au@SiO2 NPs treatment restored the HG effect. Furthermore, excess production of ROS/RNS was associated with mitochondrial dysfunction, characterized by loss of mitochondrial membrane potential (ΔΨm), and increased in mitochondrial mass, which was restored by Au@SiO2 NPs treatment in keratinocyte cells. In addition, HG-induced excess production of ROS/RNA caused an increased in the biomolecules damage including lipid peroxidation (LPO), and protein carbonylation (PC), 8-oxoguanine DNA glycosylase-1 (OGG1) expression and increased 8-hydroxydeoxyguanosine (8-OHdG) accumulations in DNA, leading to activation of ERK1/2MAPK, AKT and tuberin pathway, inflammatory reaction, and finally apoptotic cell death. In conclusion, our findings showed that Au@SiO2 NPs treatment improved the HG-induced keratinocytes injury by suppressing the oxidative/nitrosative stress, elevating the antioxidant defence system, thereby inhibiting the inflammatory mediators and apoptosis, which may be a therapeutic cure for the diabetic keratinocyte problems.


Diabetes Mellitus , Metal Nanoparticles , Nanoparticles , Humans , Antioxidants/pharmacology , Antioxidants/metabolism , Reactive Oxygen Species/metabolism , Silicon Dioxide/toxicity , Silicon Dioxide/metabolism , Gold/pharmacology , Signal Transduction , Metal Nanoparticles/toxicity , Oxidative Stress , Diabetes Mellitus/metabolism , Keratinocytes/metabolism , Apoptosis
13.
Opt Express ; 31(8): 12880-12893, 2023 Apr 10.
Article En | MEDLINE | ID: mdl-37157438

The generation of below-threshold harmonics in gas-jets constitutes a promising path towards optical frequency combs in the vacuum ultra-violet (VUV) spectral range. Of particular interest is the 150 nm range, which can be exploited to probe the nuclear isomeric transition of the Thorium-229 isotope. Using widely available high-power, high-repetition-rate Ytterbium-based laser sources, VUV frequency combs can be generated through the process of below-threshold harmonic generation, in particular 7th harmonic generation of 1030 nm. Knowledge about the achievable efficiencies of the harmonic generation process is crucial for the development of suitable VUV sources. In this work, we measure the total output pulse energies and conversion efficiencies of below-threshold harmonics in gas-jets in a phase-mismatched generation scheme using Argon and Krypton as nonlinear media. Using a 220 fs, 1030 nm source, we reach a maximum conversion efficiency of 1.1 × 10-5 for the 7th harmonic (147 nm) and 0.78 × 10-4 for the 5th harmonic (206 nm). In addition, we characterize the 3rd harmonic of a 178 fs, 515 nm source with a maximum efficiency of 0.3%.

14.
Life Sci ; 326: 121796, 2023 Aug 01.
Article En | MEDLINE | ID: mdl-37230378

Chronic pain is a common and debilitating condition with a huge social and economic burden worldwide. Currently, available drugs in clinics are not adequately effective and possess a variety of severe side effects leading to treatment withdrawal and poor quality of life. The ongoing search for new therapeutics with minimal side effects for chronic pain management remains a high research priority. Erythropoietin-producing human hepatocellular carcinoma cell receptor (Eph) is a tyrosine kinase receptor that is involved in neurodegenerative disorders, including pain. The Eph receptor interacts with several molecular switches, such as N methyl d-aspartate receptor (NMDAR), mitogen-activated protein kinase (MAPK), calpain 1, caspase 3, protein kinase a (PKA), and protein kinase Cy (PKCy), which in turn regulates pathophysiology of chronic pain. Here we highlight the emerging evidence of the Ephs/ephrin system as a possible near-future therapeutic target for the treatment of chronic pain and discuss the various mechanism of its involvement. We critically analyse the present status of Eph receptor system and conclude that extrapolating the pharmacological and genetic approaches using a strong therapeutic development framework could serve as next-generation analgesics for the management of chronic pain.


Chronic Pain , Ephrins , Humans , Ephrins/metabolism , Receptor, EphA1/metabolism , Chronic Pain/drug therapy , Quality of Life , Signal Transduction
15.
Cell Rep Med ; 4(4): 101003, 2023 04 18.
Article En | MEDLINE | ID: mdl-37044090

Targeting germline (gl-) precursors of broadly neutralizing antibodies (bNAbs) is acknowledged as an important strategy for HIV-1 vaccines. The VRC01-class of bNAbs is attractive because of its distinct genetic signature. However, VRC01-class bNAbs often require extensive somatic hypermutation, including rare insertions and deletions. We describe a BG505 SOSIP trimer, termed GT1.2, to optimize binding to gl-CH31, the unmutated common precursor of the CH30-34 bNAb lineage that acquired a large CDRH1 insertion. The GT1.2 trimer activates gl-CH31 naive B cells in knock-in mice, and B cell responses could be matured by selected boosting immunogens to generate cross-reactive Ab responses. Next-generation B cell sequencing reveals selection for VRC01-class mutations, including insertions in CDRH1 and FWR3 at positions identical to VRC01-class bNAbs, as well as CDRL1 deletions and/or glycine substitutions to accommodate the N276 glycan. These results provide proof of concept for vaccine-induced affinity maturation of B cell lineages that require rare insertions and deletions.


HIV Seropositivity , HIV-1 , Mice , Animals , Broadly Neutralizing Antibodies , Antibodies, Neutralizing , HIV-1/genetics , HIV Antibodies , Vaccination
16.
Nat Commun ; 14(1): 557, 2023 02 02.
Article En | MEDLINE | ID: mdl-36732521

Cardiovascular disease-related deaths (one-third of global deaths) can be reduced with a simple screening test for better biomarkers than the current lipid and lipoprotein profiles. We propose using a highly atheroprotective subset of HDL with colocalized PON1 (PON1-HDL) for superior cardiovascular risk assessment. However, direct quantification of HDL proteomic subclasses are complicated by the peroxides/antioxidants associated with HDL interfering with redox reactions in enzymatic calorimetric and electrochemical immunoassays. Hence, we developed an enzyme-free Nanoparticle-Gated Electrokinetic Membrane Sensor (NGEMS) platform for quantification of PON1-HDL in plasma within 60 min, with a sub-picomolar limit of detection, 3-4 log dynamic range and without needing sample pretreatment or individual-sample calibration. Using NGEMS, we report our study on human plasma PON1-HDL as a cardiovascular risk marker with AUC~0.99 significantly outperforming others (AUC~0.6-0.8), including cholesterol/triglycerides tests. Validation for a larger cohort can establish PON1-HDL as a biomarker that can potentially reshape cardiovascular landscape.


Cardiovascular Diseases , Humans , Cardiovascular Diseases/diagnosis , Proteomics , Risk Factors , Lipoproteins , Heart Disease Risk Factors , Aryldialkylphosphatase , Cholesterol, HDL
17.
J Colloid Interface Sci ; 632(Pt A): 196-215, 2023 Feb 15.
Article En | MEDLINE | ID: mdl-36413945

In the present study, the excellent photocatalytic activity of n-ZnO/n-SnO2 heterojunction integrated with reduced graphene oxide nanosheets was explored towards the elimination of different organic pollutants viz. p-bromophenol, bisphenol A, and ofloxacin from water. n-ZnO/n-SnO2 heterojunction was decorated with a different weight percentage of reduced graphene oxide via a facile refluxing method. The structural, morphological and optical properties of the as-prepared n-ZnO/n-SnO2 heterojunction-reduced graphene oxide nanocomposites were investigated systematically. XRD, Raman and FT-IR confirmed the hexagonal wurtzite and tetragonal rutile structures of ZnO and SnO2 crystals in different nanocomposites. Cube and spherical-shaped surface structures were demonstrated by TEM and FE-SEM analysis for ZnO and SnO2, respectively. The maximum photocatalytic productivity of nanocomposite with 5 wt% reduced graphene oxide was observed at about 98.64 % and 98.50 % towards the elimination of p-bromophenol and bisphenol A, respectively after 180 min exposure of UV light. Similarly, this productivity was also observed at about 99.13 % towards the elimination of ofloxacin after 120 min irradiation of UV light. The outstanding photocatalytic activity of nanocomposite with 5 wt% reduced graphene oxide has been proven by the presence of homotypic n-ZnO/n-SnO2 and reduced graphene oxide nanosheets owing to the synergistic effect amongst them resulting in remarkable separation of charge carriers, which is responsible for the larger rate of reactive oxygen species generation and enhanced photodegradation of p-bromophenol, bisphenol A and ofloxacin. In this study, the results illustrated that the photocatalytic degradation of p-bromophenol, bisphenol A and ofloxacin using n-ZnO/n-SnO2 heterojunction-reduced graphene oxide nanocomposites is predominantly based on the hydroxyl radicals and superoxide radical anion as main reactive oxygen species as compared to 1O2. A reasonable photodegradation mechanism using prepared nanocomposites under investigation has also been proposed.


Anti-Bacterial Agents , Zinc Oxide , Reactive Oxygen Species , Spectroscopy, Fourier Transform Infrared , Temperature , Ofloxacin
18.
Life Sci ; 312: 121208, 2023 Jan 01.
Article En | MEDLINE | ID: mdl-36427546

Growing evidence indicates that skin injuries are a common complication of diabetes. However, the cellular and molecular mechanisms of high glucose (HG) environment trigger nitrosative stress-mediated inflammation and apoptosis in keratinocytes remains unknown. Here we investigated whether reactive nitrogen species (RNS) induced by HG environment restrain antioxidant activity, and mitochondrial dysfunction leading to inflammation, and apoptosis via stress signaling pathways in keratinocytes. Our results established that the HG environment enhanced the production of nitric oxide (NO) and peroxynitrite anion (ONOO-) by inducible NO synthase (iNOS) in keratinocytes. Overproduction of RNS in HG environment suppress the antioxidants activity leading to mitochondrial dysfunction, characterized by loss of mitochondrial membrane potential (ΔΨm), increase in mitochondrial mass, decrease in mitochondrial transcription factor A(TFAM), increase in mitochondrial DNA (mtDNA) displacement loop (D-loop) and decrease in glycolytic flux concentration, which was attenuated by pharmacological inhibitors of NO/ONOO-, Nω-Nitro-l-argininemethyl ester hydrochloride (NAME)/hydralazine hydrochloride (Hyd.HCl). Excess production of RNS in HG environment restrained 8-oxoguanine DNA glycosylase-1 (OGG1) expression and increased 8-hydroxydeoxyguanosine (8-OHdG) accumulations in DNA were regulated by NO or ONOO-. Further, HG-induced RNA production caused an increase in the production of inflammatory mediators accompanied by activation of ERK1/2MAPK/Akt/tuberin-mTOR/IRF3 signaling cascade, lipid peroxidation (LPO), and protein carbonylation (PC) reactions followed by breakdown the cell-cell communication and apoptosis. Pre-treatment of cell with NAME/Hyd.HCl, diminished the expression of ERK1/2MAPK/Akt/tuberin-mTOR/IRF3, inflammatory mediators, and attenuated apoptosis in keratinocytes. Together, our results indicated that excess production of RNS in HG environment triggered inflammation and apoptosis, mediated by activation of ERK1/2MAPK/Akt/tuberin-mTOR/IRF3 signaling cascades in keratinocytes.


Proto-Oncogene Proteins c-akt , Reactive Nitrogen Species , Humans , Reactive Nitrogen Species/metabolism , Tuberous Sclerosis Complex 2 Protein/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Reactive Oxygen Species/metabolism , Oxidative Stress , Apoptosis , Inflammation/metabolism , Keratinocytes/metabolism , TOR Serine-Threonine Kinases/metabolism , Mitochondria/metabolism , Antioxidants/pharmacology , Inflammation Mediators/metabolism , Glucose/pharmacology , Glucose/metabolism
19.
Indian J Pediatr ; 90(9): 873-879, 2023 09.
Article En | MEDLINE | ID: mdl-35867274

OBJECTIVE: To compare the efficacy of gabapentin as add-on therapy to trihexyphenidyl in the treatment of children with dyskinetic cerebral palsy (CP). METHODS: An open-labelled, randomized, controlled trial was conducted among children aged 3-9 y with dyskinetic CP [Gross Motor Functional Classification System (GMFCS) 4-5]. Participants were assigned into two groups: gabapentin with trihexyphenidyl (n = 30) and trihexyphenidyl alone (n = 30). Dyskinesia Impairment Scale (DIS), Dystonia Severity Assessment Plan (DSAP), and International Classification of Functioning, Disability, and Health-Children and Youth Version (ICF-CY) were measured at baseline, 4 and 12 wk. RESULTS: There was significant reduction in baseline dystonia in both the groups (DIS: p < 0.001; DSAP: p = 0.007; ICF-CY: p < 0.001) but when data were compared between the groups, there was no significant difference in the severity of dystonia at 4 wk and at 12 wk (DIS: p = 0.09; DSAP: p = 0.49; ICF-CY: p = 0.25). Constipation was the commonest side effect observed in both the groups [3 (11.5%) vs. 4 (14.3%)]. CONCLUSION: Trihexyphenidyl alone is as effective as combination of gabapentin with trihexyphenidyl in decreasing the severity of dystonia at 12 wk. Hence, there is no added benefit of gabapentin as add-on therapy for dystonia among children with dyskinetic CP. TRIAL REGISTRATION: CTRI/2019/04/018603.


Cerebral Palsy , Dystonia , Adolescent , Humans , Cerebral Palsy/drug therapy , Trihexyphenidyl/therapeutic use , Gabapentin/therapeutic use , Dystonia/drug therapy
20.
Molecules ; 27(23)2022 Nov 25.
Article En | MEDLINE | ID: mdl-36500313

Natural products are being targeted as alternative anticancer agents due to their non-toxic and safe nature. The present study was conducted to explore the in vitro anticancer potential of Justicia adhatoda (J. adhatoda) leaf extract. The methanolic leaf extract was prepared, and the phytochemicals and antioxidant potential were determined by LCMS analysis and DPPH radical scavenging assay, respectively. A docking study performed with five major alkaloidal phytoconstituents showed that they had a good binding affinity towards the active site of NF-κB. Cell viability assay was carried out in five different cell lines, and the extract exhibited the highest cytotoxicity in MCF-7, a breast cancer cell line. Extract-treated cells showed a significant increase in nitric oxide and reactive oxygen species production. Cell cycle analysis showed an arrest in cell growth at the Sub-G0 phase. The extract successfully inhibited cell migration and colony formation and altered mitochondrial membrane potential. The activities of superoxide dismutase and glutathione were also found to decrease in a dose-dependent manner. The percentage of apoptotic cells was found to increase in a dose-dependent manner in MCF-7 cells. The expressions of caspase-3, Bax, and cleaved-PARP were increased in extract-treated cells. An increase in the expression of NF-κB was found in the cytoplasm in extract-treated cells. J. adhatoda leaf extract showed a potential anticancer effect in MCF-7 cells.


Breast Neoplasms , Justicia , Humans , Female , Justicia/chemistry , Methanol/chemistry , NF-kappa B/pharmacology , Breast Neoplasms/drug therapy , Plant Extracts/pharmacology , Plant Extracts/chemistry , MCF-7 Cells , Plant Leaves , Apoptosis
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