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1.
Nature ; 599(7886): 628-634, 2021 11.
Article in English | MEDLINE | ID: mdl-34662886

ABSTRACT

A major goal in human genetics is to use natural variation to understand the phenotypic consequences of altering each protein-coding gene in the genome. Here we used exome sequencing1 to explore protein-altering variants and their consequences in 454,787 participants in the UK Biobank study2. We identified 12 million coding variants, including around 1 million loss-of-function and around 1.8 million deleterious missense variants. When these were tested for association with 3,994 health-related traits, we found 564 genes with trait associations at P ≤ 2.18 × 10-11. Rare variant associations were enriched in loci from genome-wide association studies (GWAS), but most (91%) were independent of common variant signals. We discovered several risk-increasing associations with traits related to liver disease, eye disease and cancer, among others, as well as risk-lowering associations for hypertension (SLC9A3R2), diabetes (MAP3K15, FAM234A) and asthma (SLC27A3). Six genes were associated with brain imaging phenotypes, including two involved in neural development (GBE1, PLD1). Of the signals available and powered for replication in an independent cohort, 81% were confirmed; furthermore, association signals were generally consistent across individuals of European, Asian and African ancestry. We illustrate the ability of exome sequencing to identify gene-trait associations, elucidate gene function and pinpoint effector genes that underlie GWAS signals at scale.


Subject(s)
Biological Specimen Banks , Databases, Genetic , Exome Sequencing , Exome/genetics , Africa/ethnology , Asia/ethnology , Asthma/genetics , Diabetes Mellitus/genetics , Europe/ethnology , Eye Diseases/genetics , Female , Genetic Predisposition to Disease/genetics , Genetic Variation , Genome-Wide Association Study , Humans , Hypertension/genetics , Liver Diseases/genetics , Male , Mutation , Neoplasms/genetics , Quantitative Trait, Heritable , United Kingdom
2.
Nature ; 586(7831): 749-756, 2020 10.
Article in English | MEDLINE | ID: mdl-33087929

ABSTRACT

The UK Biobank is a prospective study of 502,543 individuals, combining extensive phenotypic and genotypic data with streamlined access for researchers around the world1. Here we describe the release of exome-sequence data for the first 49,960 study participants, revealing approximately 4 million coding variants (of which around 98.6% have a frequency of less than 1%). The data include 198,269 autosomal predicted loss-of-function (LOF) variants, a more than 14-fold increase compared to the imputed sequence. Nearly all genes (more than 97%) had at least one carrier with a LOF variant, and most genes (more than 69%) had at least ten carriers with a LOF variant. We illustrate the power of characterizing LOF variants in this population through association analyses across 1,730 phenotypes. In addition to replicating established associations, we found novel LOF variants with large effects on disease traits, including PIEZO1 on varicose veins, COL6A1 on corneal resistance, MEPE on bone density, and IQGAP2 and GMPR on blood cell traits. We further demonstrate the value of exome sequencing by surveying the prevalence of pathogenic variants of clinical importance, and show that 2% of this population has a medically actionable variant. Furthermore, we characterize the penetrance of cancer in carriers of pathogenic BRCA1 and BRCA2 variants. Exome sequences from the first 49,960 participants highlight the promise of genome sequencing in large population-based studies and are now accessible to the scientific community.


Subject(s)
Databases, Genetic , Exome Sequencing , Exome/genetics , Loss of Function Mutation/genetics , Phenotype , Aged , Bone Density/genetics , Collagen Type VI/genetics , Demography , Female , Genes, BRCA1 , Genes, BRCA2 , Genotype , Humans , Ion Channels/genetics , Male , Middle Aged , Neoplasms/genetics , Penetrance , Peptide Fragments/genetics , United Kingdom , Varicose Veins/genetics , ras GTPase-Activating Proteins/genetics
3.
Am J Hum Genet ; 108(7): 1350-1355, 2021 07 01.
Article in English | MEDLINE | ID: mdl-34115965

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), a respiratory illness that can result in hospitalization or death. We used exome sequence data to investigate associations between rare genetic variants and seven COVID-19 outcomes in 586,157 individuals, including 20,952 with COVID-19. After accounting for multiple testing, we did not identify any clear associations with rare variants either exome wide or when specifically focusing on (1) 13 interferon pathway genes in which rare deleterious variants have been reported in individuals with severe COVID-19, (2) 281 genes located in susceptibility loci identified by the COVID-19 Host Genetics Initiative, or (3) 32 additional genes of immunologic relevance and/or therapeutic potential. Our analyses indicate there are no significant associations with rare protein-coding variants with detectable effect sizes at our current sample sizes. Analyses will be updated as additional data become available, and results are publicly available through the Regeneron Genetics Center COVID-19 Results Browser.


Subject(s)
COVID-19/diagnosis , COVID-19/genetics , Exome Sequencing , Exome/genetics , Genetic Predisposition to Disease , Hospitalization/statistics & numerical data , COVID-19/immunology , COVID-19/therapy , Female , Humans , Interferons/genetics , Male , Prognosis , SARS-CoV-2 , Sample Size
4.
Chembiochem ; 25(2): e202300652, 2024 01 15.
Article in English | MEDLINE | ID: mdl-37921481

ABSTRACT

The increase in antibacterial drug resistance is threatening global health conditions. Recently, antibacterial photodynamic therapy (aPDT) has emerged as an effective antibacterial treatment with high cure gain. In this work, three Zn(II) complexes viz., [Zn(en)(acac)Cl] (1), [Zn(bpy)(acac)Cl] (2), [Zn(en)(cur)Cl] (3), where en=ethylenediamine (1 and 3), bpy=2,2'-bipyridine (2), acac=acetylacetonate (1 and 2), cur=curcumin monoanionic (3) were developed as aPDT agents. Complexes 1-3 were synthesized and fully characterized using NMR, HRMS, FTIR, UV-Vis. and fluorescence spectroscopy. The HOMO-LUMO energy gap (Eg), and adiabatic splittings (ΔS1-T1 and ΔS0-T1 ) obtained from DFT calculation indicated the photosensivity of the complexes. These complexes have not shown any potent antibacterial activity under dark conditions but the antibacterial activity of these complexes was significantly enhanced upon light exposure (MIC value up to 0.025 µg/mL) due to their light-mediated 1 O2 generation abilities. The molecular docking study suggested that complexes 1-3 interact efficiently with DNA gyrase B (PDB ID: 4uro). Importantly, 1-3 did not show any toxicity toward normal HEK-293 cells. Overall, in this work, we have demonstrated the promising potential of Zn(II) complexes as effective antibacterial agents under the influence of visible light.


Subject(s)
Coordination Complexes , Curcumin , Photochemotherapy , Humans , Curcumin/pharmacology , Molecular Docking Simulation , Coordination Complexes/chemistry , Density Functional Theory , HEK293 Cells , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Zinc/chemistry
5.
Langmuir ; 40(23): 12226-12238, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38814099

ABSTRACT

We have red-shifted the light absorbance property of a Re(I)-tricarbonyl complex via distant conjugation of a ferrocene moiety and developed a novel complex ReFctp, [Re(Fctp)(CO)3Cl], where Fctp = 4'-ferrocenyl-2,2':6',2″-terpyridine. ReFctp showed green to red light absorption ability and blue emission, indicating its potential for photodynamic therapy (PDT) application. The conjugation of ferrocene introduced ferrocene-based transitions, which lie at a higher wavelength within the PDT therapeutic window. The time-dependent density functional theory and excited state calculations revealed an efficient intersystem crossing for ReFctp, which is helpful for PDT. ReFctp elicited both PDT type I and type II pathways for reactive oxygen species (ROS) generation and facilitated NADH (1,4-dihydro-nicotinamide adenine dinucleotide) oxidation upon exposure to visible light. Importantly, ReFctp showed effective penetration through the layers of clinically relevant 3D multicellular tumor spheroids and localized primarily in mitochondria (Pearson's correlation coefficient, PCC = 0.65) of A549 cancer cells. ReFctp produced more than 20 times higher phototoxicity (IC50 ∼1.5 µM) by inducing ROS generation and altering mitochondrial membrane potential in A549 cancer cells than the nonferrocene analogue Retp, [Re(CO)3(tp)Cl], where tp = 2,2':6',2″-terpyridine. ReFctp induced apoptotic mode of cell death with a notable photocytotoxicity index (PI, PI = IC50dark/IC50light) and selectivity index (SI, SI = normal cell's IC50dark/cancer cell's IC50light) in the range of 25-33.


Subject(s)
Antineoplastic Agents , Ferrous Compounds , Light , Metallocenes , Ferrous Compounds/chemistry , Ferrous Compounds/pharmacology , Humans , Metallocenes/chemistry , Metallocenes/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/radiation effects , Antineoplastic Agents/chemical synthesis , Reactive Oxygen Species/metabolism , Density Functional Theory , Photochemotherapy , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Photosensitizing Agents/radiation effects , Photosensitizing Agents/chemical synthesis , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Coordination Complexes/radiation effects , Coordination Complexes/chemical synthesis , Cell Line, Tumor , Drug Screening Assays, Antitumor , Red Light
6.
Inorg Chem ; 63(16): 7493-7503, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38578920

ABSTRACT

The relentless increase in drug resistance of platinum-based chemotherapeutics has opened the scope for other new cancer therapies with novel mechanisms of action (MoA). Recently, photocatalytic cancer therapy, an intrusive catalytic treatment, is receiving significant interest due to its multitargeting cell death mechanism with high selectivity. Here, we report the synthesis and characterization of three photoresponsive Ru(II) complexes, viz., [Ru(ph-tpy)(bpy)Cl]PF6 (Ru1), [Ru(ph-tpy)(phen)Cl]PF6 (Ru2), and [Ru(ph-tpy)(aip)Cl]PF6 (Ru3), where, ph-tpy = 4'-phenyl-2,2':6',2″-terpyridine, bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline, and aip = 2-(anthracen-9-yl)-1H-imidazo[4,5-f][1,10] phenanthroline, showing photocatalytic anticancer activity. The X-ray crystal structures of Ru1 and Ru2 revealed a distorted octahedral geometry with a RuN5Cl core. The complexes showed an intense absorption band in the 440-600 nm range corresponding to the metal-to-ligand charge transfer (MLCT) that was further used to achieve the green light-induced photocatalytic anticancer effect. The mitochondria-targeting photostable complex Ru3 induced phototoxicity with IC50 and PI values of ca. 0.7 µM and 88, respectively, under white light irradiation and ca. 1.9 µM and 35 under green light irradiation against HeLa cells. The complexes (Ru1-Ru3) showed negligible dark cytotoxicity toward normal splenocytes (IC50s > 50 µM). The cell death mechanistic study revealed that Ru3 induced ROS-mediated apoptosis in HeLa cells via mitochondrial depolarization under white or green light exposure. Interestingly, Ru3 also acted as a highly potent catalyst for NADH photo-oxidation under green light. This NADH photo-oxidation process also contributed to the photocytotoxicity of the complexes. Overall, Ru3 presented multitargeting synergistic type I and type II photochemotherapeutic effects.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Light , Pyridines , Ruthenium , Humans , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Catalysis , Cell Proliferation/drug effects , Cell Survival/drug effects , Coordination Complexes/chemical synthesis , Coordination Complexes/pharmacology , Drug Screening Assays, Antitumor , Green Light , HeLa Cells , Molecular Structure , Photochemical Processes , Pyridines/chemistry , Pyridines/pharmacology , Reactive Oxygen Species/metabolism , Ruthenium/chemistry , Ruthenium/pharmacology
7.
Forensic Sci Med Pathol ; 20(1): 106-116, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37071347

ABSTRACT

Forensic age assessments are crucial in the evaluation of criminal responsibility and preventing false age claims. Of all the methods available, the Greulich and Pyle (GP) atlas is most commonly used for age estimation purposes. Therefore, the current study sought to analyze the reliability and applicability of the GP standard and, additionally, to determine any possible association between the socioeconomic status (SES), food habits, and estimated skeletal maturity in the North Indian population. The study included 627 (334 males and 293 females) healthy children up to 19 years of age with varying SES and food habits. The skeletal age (SA) was estimated by three different evaluators using the GP atlas. The chronological mean age (CA) and SA were compared in different age cohorts. A paired t-test and a Pearson chi-square test were applied to show the difference between CA and estimated SA and the association of skeletal maturity with SES and food habits. The estimated skeletal age in males was retarded by 0.142 years or 1.72 months (p ≤ 0.05), whereas in females, it was retarded by 0.259 years or 3.12 months (p ≤ 0.05). In males, the GP method has significantly underestimated SA in age cohorts 3-4, 4-5, 6-7, 7-8, 8-9, and 12-13, whereas it overestimated in 10-11 and 18-19 years. However, in females, the SA was significantly underestimated in age groups 10-11, 12-13, and 14-15, respectively. Estimated skeletal maturity had no significant association with SES and food habits. The current study concludes that the GP atlas may not be applicable to North India's population. The observed difference in assessed skeletal maturity may be due to geographical region, genetics, hormonal effects, etc., which require further investigation. Hence, population-specific standards are necessary to determine the bone age of Indian children accurately.


Subject(s)
Age Determination by Skeleton , Asian People , Child , Male , Female , Humans , Infant , Reproducibility of Results , Age Determination by Skeleton/methods
8.
Chembiochem ; 24(6): e202200597, 2023 03 14.
Article in English | MEDLINE | ID: mdl-36385722

ABSTRACT

Sonodynamic therapy (SDT) for cancer treatment is gaining attention owing to its non-invasive property and ultrasound's (US) deep tissue penetration ability. In SDT, US activates the sonosensitizer at the target deep-seated tumors to generate reactive oxygen species (ROS), which ultimately damage tumors. However, drawbacks such as insufficient ROS production, aggregation of sonosensitizer, off-target side effects, etc., of the current organic/nanomaterial-based sonosensitizers limit the effectiveness of cancer SDT. Very recently, metal complexes with tunable physiochemical properties (such as sonostability, HOMO to LUMO energy gap, ROS generation ability, aqueous solubility, emission, etc.) have been devised as effective sonosensitizers, which could overcome the limitations of organic/nanomaterial-based sonosensitizers. This concept introduces all the reported metal-based sonosensitizers and delineates the prospects of metal complexes in cancer sonodynamic therapy. This new concept of metal-based sonosensitizer can deliver next-generation cancer drugs.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Neoplasms , Ultrasonic Therapy , Humans , Reactive Oxygen Species , Coordination Complexes/pharmacology , Coordination Complexes/therapeutic use , Neoplasms/drug therapy , Neoplasms/pathology , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor
9.
Chembiochem ; 24(10): e202300033, 2023 05 16.
Article in English | MEDLINE | ID: mdl-36763497

ABSTRACT

Four new CoII complexes, [Co(bpy)2 (acac)]Cl (1), [Co(phen)2 (acac)]Cl (2), [Co(bpy)2 (cur)]Cl (3), [Co(phen)2 (cur)]Cl (4), where bpy=2,2'-bipyridine (1 and 3), phen=1,10-phenanthroline (2 and 4), acac=acetylacetonate (1 and 2), cur=curcumin monoanion (3 and 4) have been designed, synthesized and fully characterized. The X-ray crystal structures of 1 and 2 indicated that the CoN4 O2 core has a distorted octahedral geometry. The photoactivity of these complexes was tuned by varying the π conjugation in the ligands. Curcumin complexes 3 and 4 had an intense absorption band near 435 nm, which made them useful as visible-light photodynamic therapy agents; they also showed fluorescence with λem ≈565 nm. This fluorescence was useful for studying their intracellular uptake and localization in MCF-7 breast cancer cells. The acetylacetonate complexes (1 and 2) were used as control complexes to understand the role of curcumin. The white-light-triggered anticancer profiles of the cytosol targeting complexes 3 and 4 were investigated in detail. These non-dark toxic complexes displayed significant apoptotic photo-cytotoxicity (under visible light) against MCF-7 cells through ROS generation. The control complexes 1 and 2 did not induce significant cell death in the light or dark. Interestingly, 1-4 produced a remarkable antibacterial response upon light exposure. Overall, the reported results here can increase the boundary of the CoII -based anticancer and antibacterial drug development.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Curcumin , Photochemotherapy , Humans , Curcumin/pharmacology , Curcumin/chemistry , Hydroxybutyrates , Pentanones , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Coordination Complexes/pharmacology , Coordination Complexes/chemistry , Anti-Bacterial Agents/pharmacology
10.
J Org Chem ; 88(1): 626-631, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36522290

ABSTRACT

Recently, interest has been given to developing photocatalytic anticancer drugs. This area of research is dominated by metal complexes. Here, we report the potential of lysosome/mitochondria targeting cyanine appended bipyridine compounds as the organic photocatalytic anticancer agents. The organocatalyst (bpyPCN) not only exhibits light-induced NADH oxidation but also generates intracellular ROS to demonstrate anticancer activity. This is the first example of organic compound induced catalytic NADH photo-oxidation in an aqueous solution and in cancer cells.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Neoplasms , 2,2'-Dipyridyl/pharmacology , Oxidation-Reduction , NAD , Antineoplastic Agents/pharmacology
11.
Indian J Public Health ; 67(3): 370-375, 2023.
Article in English | MEDLINE | ID: mdl-37929377

ABSTRACT

Background: Thyroid dysfunction (TD) is considered a common cause of secondary hypertension (HT). Therefore, correcting TD may help in quicker and sustained achievement of desired blood pressure goals. However, there is a paucity of literature from India which estimates the relationship of HT with TD. Objectives: The objective of the study was to estimate the prevalence of TD with HT and to identify associated factors among Indian population. Materials and Methods: The survey data of the National Family Health Survey 4 (NFHS-4), conducted in India during 2015-2016, were analyzed using R statistical software for estimating the relationship between a history of HT and TD among women (N = 687246) aged 15-49 years and men (N = 108492) aged 15-54 years. Descriptive statistical tests and logistic regression were applied. Results: Among the persons suffering from the TD, the prevalence of HT was 32.8%, which was significantly higher than the prevalence of HT (21.9%) in euthyroid individuals. Further, the prevalence of TD was higher among hypertensive adults (2.5%) compared to nonhypertensive (1.5%). Conclusions: The study reported a higher prevalence of TD among the hypertensive persons and higher prevalence of HT among cases of TD. Therefore, screening for thyroid disorders should be routinely considered for better management of HT.


Subject(s)
Hypertension , Thyroid Diseases , Male , Adult , Humans , Female , Prevalence , India/epidemiology , Thyroid Diseases/epidemiology , Thyroid Diseases/diagnosis , Hypertension/epidemiology , Risk Factors , Health Surveys
12.
Chembiochem ; 23(15): e202200201, 2022 08 03.
Article in English | MEDLINE | ID: mdl-35438233

ABSTRACT

Immunotherapy has made great progress in clinical cancer treatment in recent years, but its therapeutic efficacy is significantly limited by the lack of immunogenicity in the tumor microenvironment. Pyroptosis is a type of programmed cell death in which the dying cancer cells produce inflammatory cytokines to relieve the immuno-suppressive microenvironment and thus increase anti-tumor immunity. Reactive oxygen species (ROS) produced during photodynamic therapy (PDT) are one of the efficient activators that induce pyroptosis. Recently, a few photosensitizers have emerged with the ability to induce immunogenic cancer cell death via pyroptosis, opening a new field for PDT. This highlight introduces the latest research on antitumor strategies achieved by the combination of immunotherapy and photodynamic therapy through photo-pyroptosis.


Subject(s)
Neoplasms , Photochemotherapy , Cell Line, Tumor , Humans , Immunotherapy , Neoplasms/drug therapy , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Pyroptosis , Tumor Microenvironment
13.
Int J Obes (Lond) ; 46(10): 1925-1935, 2022 10.
Article in English | MEDLINE | ID: mdl-35978103

ABSTRACT

BACKGROUND: There is now good evidence that events during gestation significantly influence the developmental well-being of an individual in later life. This study aimed to investigate the relationships between intrauterine growth trajectories determined by serial ultrasound and subsequent markers of adiposity and inflammation in the 27-year-old adult offspring from the Raine Study, an Australian longitudinal pregnancy cohort. METHODS: Ultrasound fetal biometric measurements including abdominal circumference (AC), femur length (FL), and head circumference (HC) from 1333 mother-fetal pairs (Gen1-Gen2) in the Raine Study were used to develop fetal growth trajectories using group-based trajectory modeling. Linear mixed modeling investigated the relationship between adult body mass index (BMI), waist circumference (WC), and high-sensitivity C-reactive protein (hs-CRP) of Gen2 at 20 (n = 485), 22 (n = 421) and 27 (n = 437) years and the fetal growth trajectory groups, adjusting for age, sex, adult lifestyle factors, and maternal factors during pregnancy. RESULTS: Seven AC, five FL and five HC growth trajectory groups were identified. Compared to the average-stable (reference) group, a lower adult BMI was observed in two falling AC trajectories: (ß = -1.45 kg/m2, 95% CI: -2.43 to -0.46, P = 0.004) and (ß = -1.01 kg/m2, 95% CI: -1.96 to -0.05, P = 0.038). Conversely, higher adult BMI (2.58 kg/m2, 95% CI: 0.98 to 4.18, P = 0.002) and hs-CRP (37%, 95% CI: 9-73%, P = 0.008) were observed in a rising FL trajectory compared to the reference group. A high-stable HC trajectory associated with 20% lower adult hs-CRP (95% CI: 5-33%, P = 0.011). CONCLUSION: This study highlights the importance of understanding causes of the unique patterns of intrauterine growth. Different fetal growth trajectories from early pregnancy associate with subsequent adult adiposity and inflammation, which predispose to the risk of diabetes and cardiometabolic disease.


Subject(s)
Adiposity , C-Reactive Protein , Adult , Australia/epidemiology , Biomarkers , Female , Fetal Development , Gestational Age , Humans , Inflammation , Obesity , Pregnancy , Ultrasonography, Prenatal , Young Adult
14.
Soft Matter ; 17(39): 8902-8914, 2021 Oct 13.
Article in English | MEDLINE | ID: mdl-34545899

ABSTRACT

The microstructure and properties of calcium-silicate-hydrate (C-S-H) gels are largely controlled by the physicochemical environment during their precipitation. However, the role of the steric repulsive environment induced by the pore solution chemistry on the kinetics, structure, and properties of C-S-H gels remains unclear. Here, we develop two potential formalisms, namely sinusoidal and polynomial, to simulate the role of steric repulsions in C-S-H. The results show excellent agreement with experimental observations of precipitation kinetics and elastic properties. We demonstrate that the repulsive interactions result in delayed precipitation and percolation, and an open and branched microstructure. Interestingly, the elastic properties (which are equilibrium properties) are also significantly affected by these second-neighbor interactions. Overall, the present study demonstrates that the kinetics, structure, and equilibrium properties of colloidal gels are controlled by the steric repulsions induced by the chemical environment.

15.
Appl Opt ; 58(10): 2687-2694, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-31045071

ABSTRACT

High-speed optical amplitude modulation is important for optical communication systems and sensors. Moreover, nano-optical modulators are important for developing optical-communication-aided high-speed parallel-operation processors and micro-biomedical sensors for inside-blood-capillary examinations or microsurgery operations. In this paper, we have designed a plasmonic resonant tunable metasurface with barium titanate (BTO) as a nanoscale optical modulator with a high modulation index and high speed. The BTO operated well in the VIS and near-IR ranges, enabling tunable optical devices with zero dispersion and high speed. The results obtained by rigorous finite-element method simulations have shown that the hypothesized device has good potential for fast modulation in related applications, e.g., modulators in nano-optical systems, nano-optical switches and nanosensors.

16.
Nanotechnology ; 27(16): 165703, 2016 Apr 22.
Article in English | MEDLINE | ID: mdl-26954366

ABSTRACT

We demonstrated three-dimensional PMMA-based photonic crystal (3D-PC) nanostructures attached to Au nanoparticles (AuNPs), which undergo self-organization into super lattice planes and enhance the fluorescence properties. This new structure exhibited interesting tunable spectral, peak broadening plasmonic behavior because of strong plasmonic interaction at high laser powers. The presented work provides an important tool to improve the efficiency of dye laser applications.

17.
Chem Res Toxicol ; 28(6): 1133-43, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-25915446

ABSTRACT

Past observational and toxicity studies have established an association between the deaths of children and consumption of Cassia occidentalis (CO) seeds. We recently reported chemical evidence of this association following the identification of toxic anthraquinones (AQs), viz. aloe-emodin, chrysophanol, emodin, physcion, and rhein, in CO seeds (Panigrahi, G. K. et al. (2015), Chem. Res. Toxicol. DOI: 10.1021/acs.chemrestox.5b00056 ). Of these five AQs, earlier studies have shown rhein to be the most cytotoxic AQ in hepatocytes. Therefore, the present study was designed to investigate the effect of rhein on rat primary hepatocytes. Results indicated that rhein (50 µM) causes apoptosis in rat primary hepatocytes by generating reactive oxygen species (ROS), increasing intracellular Ca(2+), decreasing the mitochondrial membrane potential, and depleting intracellular glutathione content. At the molecular level, rhein-induced DNA damage results in overexpression of γ-H2AX protein (2.5-fold), thereby causing enhancement of p53 (4.5-fold) and p21 (3.6-fold), leading to intrinsic pathway-mediated apoptosis involving Bax, bcl2, cytochrome c, caspases 3 and 9, and poly-ADP ribose polymerase. Further, it was observed that rhein-induced ROS generation is also involved in the modulation of signaling molecules like MAPK kinases, including ERK1/2, p38, and JNK, and mitochondrial energetics proteins, including complexes II-V, p-AMPK, and Sirt-1. It was shown that 100 nM cyclosporine A was the most effective among the different protective agents at preventing apoptosis in hepatocytes by interfering in various metabolic pathways which were found to be altered by rhein.


Subject(s)
Anthraquinones/toxicity , Apoptosis/drug effects , Cyclosporine/pharmacology , Hepatocytes/drug effects , Hepatocytes/metabolism , Animals , Cell Survival/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Male , Metabolic Networks and Pathways/drug effects , Rats , Rats, Wistar , Structure-Activity Relationship , Time Factors
18.
Biochem Genet ; 52(3-4): 137-52, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24243146

ABSTRACT

Sequence-related amplified polymorphism markers were used to assess the genetic structure in three natural populations of Morus alba from trans-Himalaya. Multilocation sampling was conducted across 14 collection sites. The overall genetic diversity estimates were high: percentage polymorphic loci 89.66%, Nei's gene diversity 0.2286, and Shannon's information index 0.2175. At a regional level, partitioning of variability assessed using analysis of molecular variance (AMOVA), revealed 80% variation within and 20% among collection sites. Pattern appeared in STRUCTURE, BARRIER, and AMOVA, clearly demonstrating gene flow between the Indus and Suru populations and a geographic barrier between the Indus-Suru and Nubra populations, which effectively hinders gene flow. The results showed significant genetic differentiation, population structure, high to restricted gene flow, and high genetic diversity. The assumption that samples collected from the three valleys represent three different populations does not hold true. The fragmentation present in trans-Himalaya was more natural and less anthropogenic.


Subject(s)
Morus/genetics , Gene Flow , Genetic Markers , Genetic Structures , Genetic Variation , Genetics, Population , Geography , India , Phylogeny , Polymorphism, Genetic
19.
J Med Chem ; 67(8): 6537-6548, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38603561

ABSTRACT

Herein, we have compared the effectivity of light-based photoactivated cancer therapy and ultrasound-based sonodynamic therapy with Re(I)-tricarbonyl complexes (Re1-Re3) against cancer cells. The observed photophysical and TD-DFT calculations indicated the potential of Re1-Re3 to act as good anticancer agents under visible light/ultrasound exposure. Re1 did not display any dark- or light- or ultrasound-triggered anticancer activity. However, Re2 and Re3 displayed concentration-dependent anticancer activity upon light and ultrasound exposure. Interestingly, Re3 produced 1O2 and OH• on light/ultrasound exposure. Moreover, Re3 induced NADH photo-oxidation in PBS and produced H2O2. To the best of our knowledge, NADH photo-oxidation has been achieved here with the Re(I) complex for the first time in PBS. Additionally, Re3 released CO upon light/ultrasound exposure. The cell death mechanism revealed that Re3 produced an apoptotic cell death response in HeLa cells via ROS generation. Interestingly, Re3 showed slightly better anticancer activity under light exposure compared to ultrasound exposure.


Subject(s)
Antineoplastic Agents , Phenanthrolines , Humans , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Ligands , HeLa Cells , Phenanthrolines/chemistry , Phenanthrolines/pharmacology , Rhenium/chemistry , Rhenium/pharmacology , Coordination Complexes/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/chemical synthesis , Coordination Complexes/radiation effects , Apoptosis/drug effects , Light , Reactive Oxygen Species/metabolism , Ultrasonic Therapy , Photochemotherapy , Drug Screening Assays, Antitumor , Neoplasms/drug therapy
20.
Int J Low Extrem Wounds ; : 15347346241246339, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38659348

ABSTRACT

Chronic wounds have long been a significant public health concern, but the true impact of these wounds is unknown since research designs and measuring techniques vary, leading to inconsistent estimates. The definition of a wound is a loss of epithelial continuity caused by damage to the tissue. The following conditions can cause chronic wounds: panniculitis, pyoderma gangrenosum, traumatic, neurological, metabolic, hematologic, neoplastic, or infection-related. The growing global incidence of diabetes and the aging population necessitate greater attention to chronic wounds. Regrettably, it is sad that significant healthcare institutions have overlooked wound research. The study of health-related illnesses and occurrences in particular populations, including their distribution, frequency, and determinants, and the application of this research to control health problems.

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