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1.
J Am Chem Soc ; 146(13): 8928-8938, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38526298

RESUMO

Understanding the effect of noncovalent interactions of intermediates at the polarized catalyst-electrolyte interface on water oxidation kinetics is key for designing more active and stable electrocatalysts. Here, we combine operando optical spectroscopy, X-ray absorption spectroscopy (XAS), and surface-enhanced infrared absorption spectroscopy (SEIRAS) to probe the effect of noncovalent interactions on the oxygen evolution reaction (OER) activity of IrOx in acidic and alkaline electrolytes. Our results suggest that the active species for the OER (Ir4.x+-*O) binds much stronger in alkaline compared with acid at low coverage, while the repulsive interactions between these species are higher in alkaline electrolytes. These differences are attributed to the larger fraction of water within the cation hydration shell at the interface in alkaline electrolytes compared to acidic electrolytes, which can stabilize oxygenated intermediates and facilitate long-range interactions between them. Quantitative analysis of the state energetics shows that although the *O intermediates bind more strongly than optimal in alkaline electrolytes, the larger repulsive interaction between them results in a significant weakening of *O binding with increasing coverage, leading to similar energetics of active states in acid and alkaline at OER-relevant potentials. By directly probing the electrochemical interface with complementary spectroscopic techniques, our work goes beyond conventional computational descriptors of the OER activity to explain the experimentally observed OER kinetics of IrOx in acidic and alkaline electrolytes.

2.
J Am Chem Soc ; 146(13): 8915-8927, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38517290

RESUMO

A barrier to understanding the factors driving catalysis in the oxygen evolution reaction (OER) is understanding multiple overlapping redox transitions in the OER catalysts. The complexity of these transitions obscure the relationship between the coverage of adsorbates and OER kinetics, leading to an experimental challenge in measuring activity descriptors, such as binding energies, as well as adsorbate interactions, which may destabilize intermediates and modulate their binding energies. Herein, we utilize a newly designed optical spectroelectrochemistry system to measure these phenomena in order to contrast the behavior of two electrocatalysts, cobalt oxyhydroxide (CoOOH) and cobalt-iron hexacyanoferrate (cobalt-iron Prussian blue, CoFe-PB). Three distinct optical spectra are observed in each catalyst, corresponding to three separate redox transitions, the last of which we show to be active for the OER using time-resolved spectroscopy and electrochemical mass spectroscopy. By combining predictions from density functional theory with parameters obtained from electroadsorption isotherms, we demonstrate that a destabilization of catalytic intermediates occurs with increasing coverage. In CoOOH, a strong (∼0.34 eV/monolayer) destabilization of a strongly bound catalytic intermediate is observed, leading to a potential offset between the accumulation of the intermediate and measurable O2 evolution. We contrast these data to CoFe-PB, where catalytic intermediate generation and O2 evolution onset coincide due to weaker binding and destabilization (∼0.19 eV/monolayer). By considering a correlation between activation energy and binding strength, we suggest that such adsorbate driven destabilization may account for a significant fraction of the observed OER catalytic activity in both materials. Finally, we disentangle the effects of adsorbate interactions on state coverages and kinetics to show how adsorbate interactions determine the observed Tafel slopes. Crucially, the case of CoFe-PB shows that, even where interactions are weaker, adsorption remains non-Nernstian, which strongly influences the observed Tafel slope.

3.
Circulation ; 145(12): 877-891, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-34930020

RESUMO

BACKGROUND: Sequencing Mendelian arrhythmia genes in individuals without an indication for arrhythmia genetic testing can identify carriers of pathogenic or likely pathogenic (P/LP) variants. However, the extent to which these variants are associated with clinically meaningful phenotypes before or after return of variant results is unclear. In addition, the majority of discovered variants are currently classified as variants of uncertain significance, limiting clinical actionability. METHODS: The eMERGE-III study (Electronic Medical Records and Genomics Phase III) is a multicenter prospective cohort that included 21 846 participants without previous indication for cardiac genetic testing. Participants were sequenced for 109 Mendelian disease genes, including 10 linked to arrhythmia syndromes. Variant carriers were assessed with electronic health record-derived phenotypes and follow-up clinical examination. Selected variants of uncertain significance (n=50) were characterized in vitro with automated electrophysiology experiments in HEK293 cells. RESULTS: As previously reported, 3.0% of participants had P/LP variants in the 109 genes. Herein, we report 120 participants (0.6%) with P/LP arrhythmia variants. Compared with noncarriers, arrhythmia P/LP carriers had a significantly higher burden of arrhythmia phenotypes in their electronic health records. Fifty-four participants had variant results returned. Nineteen of these 54 participants had inherited arrhythmia syndrome diagnoses (primarily long-QT syndrome), and 12 of these 19 diagnoses were made only after variant results were returned (0.05%). After in vitro functional evaluation of 50 variants of uncertain significance, we reclassified 11 variants: 3 to likely benign and 8 to P/LP. CONCLUSIONS: Genome sequencing in a large population without indication for arrhythmia genetic testing identified phenotype-positive carriers of variants in congenital arrhythmia syndrome disease genes. As the genomes of large numbers of people are sequenced, the disease risk from rare variants in arrhythmia genes can be assessed by integrating genomic screening, electronic health record phenotypes, and in vitro functional studies. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier; NCT03394859.


Assuntos
Arritmias Cardíacas , Testes Genéticos , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/genética , Predisposição Genética para Doença , Testes Genéticos/métodos , Genômica , Células HEK293 , Humanos , Fenótipo , Estudos Prospectivos
4.
Nanotechnology ; 34(22)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36827701

RESUMO

In the present study, we describe a facile strategy for the easy removal of the heavy metal ion, Pb (II) using biosynthesized copper ferrite (CuFe2O4) Nanoparticles (Nps) prepared via a cost-effective and eco-friendly method usingPimenta dioicaleaf extract. The structural characterization was performed using UV-Visible, FT-IR, XRD, XPS, TG, SEM - EDS and TEM techniques. Various characterization techniques showed that the biosynthesized CuFe2O4nanoparticles have spherical shape with minimum aggregation and possess a size range between 7 and 16 nm. Batch experiments were carried out to analyze the adsorption efficiency of CuFe2O4Nps by varying different experimental conditions such as pH, adsorbent dose and initial metal ion concentration. From the atomic absorption spectroscopy results, the optimum removal efficiency (99.69%) occurred at a contact time of 90 min in the solution having pH 6 with 0.06 g of nanoadsorbent. The experimental data were analyzed using adsorption isotherm and fitted with kinetic models. In the present study, we report the the highest removal efficiency of 99.69% for Pb (II) ions with minimum experimental parameters which is greater than other similar reported studies. The novel CuFe2O4nanosorbent synthesized in the present study is highly effective in eliminating toxic pollutants. They also possess outstanding recycling characteristics for the effective removal of Pb (II) ions from aqueous media.This cost-effective and ecofriendly strategy could be utilized for addressing the emerging water contamination.

5.
Curr Oncol Rep ; 25(4): 379-386, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36808556

RESUMO

PURPOSE OF REVIEW: There is a paucity of evidence for managing perioperative anticoagulation in patients with cancer. This review aims to provide clinicians who provide care for patients with cancer an overview of the available information and strategies needed to provide optimal care in a perioperative setting. RECENT FINDINGS: There is new evidence available around the management of perioperative anticoagulation in patients with cancer. The new literature and guidance were analyzed and summarized in this review. Management of perioperative anticoagulation in individuals with cancer is a challenging clinical dilemma. The approach to managing anticoagulation requires clinicians to review both disease and treatment specific patient factors that can contribute to both thrombotic and bleed risks. A thorough patient-specific assessment is essential in ensuring patients with cancer receive appropriate care in the perioperative setting.


Assuntos
Neoplasias , Trombose , Humanos , Anticoagulantes/uso terapêutico , Assistência Perioperatória , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Trombose/etiologia , Trombose/prevenção & controle , Trombose/tratamento farmacológico , Neoplasias/complicações , Neoplasias/tratamento farmacológico
6.
J Am Chem Soc ; 144(19): 8454-8459, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35511107

RESUMO

Water oxidation is the step limiting the efficiency of electrocatalytic hydrogen production from water. Spectroelectrochemical analyses are employed to make a direct comparison of water oxidation reaction kinetics between a molecular catalyst, the dimeric iridium catalyst [Ir2(pyalc)2(H2O)4-(µ-O)]2+ (IrMolecular, pyalc = 2-(2'pyridinyl)-2-propanolate) immobilized on a mesoporous indium tin oxide (ITO) substrate, with that of an heterogeneous electrocatalyst, an amorphous hydrous iridium (IrOx) film. For both systems, four analogous redox states were detected, with the formation of Ir(4+)-Ir(5+) being the potential-determining step in both cases. However, the two systems exhibit distinct water oxidation reaction kinetics, with potential-independent first-order kinetics for IrMolecular contrasting with potential-dependent kinetics for IrOx. This is attributed to water oxidation on the heterogeneous catalyst requiring co-operative effects between neighboring oxidized Ir centers. The ability of IrMolecular to drive water oxidation without such co-operative effects is explained by the specific coordination environment around its Ir centers. These distinctions between molecular and heterogeneous reaction kinetics are shown to explain the differences observed in their water oxidation electrocatalytic performance under different potential conditions.

7.
J Am Chem Soc ; 144(17): 7622-7633, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35442661

RESUMO

Metal oxides and oxyhydroxides exhibit state-of-the-art activity for the oxygen evolution reaction (OER); however, their reaction mechanism, particularly the relationship between charging of the oxide and OER kinetics, remains elusive. Here, we investigate a series of Mn-, Co-, Fe-, and Zn-doped nickel oxides using operando UV-vis spectroscopy coupled with time-resolved stepped potential spectroelectrochemistry. The Ni2+/Ni3+ redox peak potential is found to shift anodically from Mn- < Co- < Fe- < Zn-doped samples, suggesting a decrease in oxygen binding energetics from Mn- to Zn-doped samples. At OER-relevant potentials, using optical absorption spectroscopy, we quantitatively detect the subsequent oxidation of these redox centers. The OER kinetics was found to have a second-order dependence on the density of these oxidized species, suggesting a chemical rate-determining step involving coupling of two oxo species. The intrinsic turnover frequency per oxidized species exhibits a volcano trend with the binding energy of oxygen on the Ni site, having a maximum activity of ∼0.05 s-1 at 300 mV overpotential for the Fe-doped sample. Consequently, we propose that for Ni centers that bind oxygen too strongly (Mn- and Co-doped oxides), OER kinetics is limited by O-O coupling and oxygen desorption, while for Ni centers that bind oxygen too weakly (Zn-doped oxides), OER kinetics is limited by the formation of oxo groups. This study not only experimentally demonstrates the relation between electroadsorption free energy and intrinsic kinetics for OER on this class of materials but also highlights the critical role of oxidized species in facilitating OER kinetics.

8.
Arch Microbiol ; 203(1): 219-231, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32803348

RESUMO

Goldfish farming gained more attention among the ornamental fishes in aquaculture industry. The occurrence of bacterial infections and further antimicrobial treatment lead to the major crisis of antibiotic resistance in aquaculture. We have isolated diverse enterobacteriaceae groups which affect the goldfish and identified their response towards 46 antimicrobials of 15 different classes. Thirteen significant bacterial isolates such as Edwardsiella tarda, Serratia marcescens, Klebsiella aerogenes, Proteus penneri, P. hauseri, Enterobacter cloacae, E. cancerogenus, E. ludwigii, Citrobacter freundii, E. coli, Kluyvera cryocrescens, Plesiomonas shigelloides and Providencia vermicola were recovered from the infected fish with the Shannon-wiener diversity index of 2.556. Multiple antibiotic resistance (MAR) index was found to be maximum for P. penneri (0.87) and minimum for C. freundii and E. cloacae (0.22), highlighting the hyper antibiotic selection pressure in the farm. The minimum concentration of antibiotics required to inhibit most of the resistant isolates was found to be > 256 mcg/ml. All the isolates were susceptible towards ciprofloxacin. Plasmid curing and further AMR tests could reveal the location of antibiotic resistance genes mainly as plasmids which determine the large extent of AMR spread through horizontal gene transfer. This study is the first of its kind to investigate the antimicrobial resistance profile of enterobacteriaceae recovered from goldfish, before and after plasmid curing.


Assuntos
Antibacterianos/farmacologia , Infecções por Enterobacteriaceae/veterinária , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Doenças dos Peixes/microbiologia , Carpa Dourada/microbiologia , Animais , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Água Doce , Transferência Genética Horizontal/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , beta-Lactamases/genética
9.
Lett Appl Microbiol ; 71(1): 108-116, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31602688

RESUMO

The indiscriminate use of antimicrobials in aquaculture results in antibiotic selection pressure and proliferation of antimicrobial resistant (AMR) bacteria. Frequent assessment of antimicrobial resistance in aquaculture environment is inevitable so as to reduce the passage of clinically important AMR from aquatic to other environment. The present study analysed the antimicrobial resistance of pathogens associated with diseased koi carp and goldfish from an ornamental fish farm. Phenotypic and genotypic characterization of the recovered isolates from both fishes revealed significant pathogens in aquaculture such as Aeromonas, Edwardsiella tarda, Acinetobacter, Lactococcus, Citrobacter, Enterobacter and Comamonas. Shannon-Wiener diversity of koi isolates (2·359) was found to be higher than that of goldfish (1·864). Antibiotic susceptibility testing using disc diffusion with 47 antibiotics revealed significant resistance pattern of Acinetobacter, Comamonas, Klebsiella and Enterobacter from goldfish and Edwardsiella, Aeromonas, Lactococcus, Enterobacter and Acinetobacter from koi with higher multiple antibiotic resistance indexes (>0·3). The minimum inhibitory concentration of antibiotics for the major resistant isolates was found to be very high with >256 µg. All the isolates were susceptible to amoxicillin, kanamycin, cefepime, cefexime, cefotaxime, ceftazidime, doripenem, ciprofloxacin and norfloxacin, recommending their successful application in the farm. SIGNIFICANCE AND IMPACT OF THE STUDY: Antimicrobial resistance is a major threat faced in aquaculture industry. The current study provides baseline information regarding the antibiotic resistance patterns of diverse pathogens recovered from ornamental koi carp and goldfish. The higher MAR index of pathogens and greater MIC of antibiotics for the resistant isolates highlighted the intense use of antibiotics in aquaculture farm. The potential of the pathogens to exhibit resistance even towards the new generation antibiotics remind the need of prudent use of antibiotics and continuous monitoring and surveillance programmes.


Assuntos
Antibacterianos/farmacologia , Bactérias/genética , Carpas/microbiologia , Água Doce/microbiologia , Carpa Dourada/microbiologia , Animais , Aquicultura , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Fazendas , Peixes/microbiologia , Humanos , Testes de Sensibilidade Microbiana
11.
Pharmacol Res ; 105: 134-45, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26808083

RESUMO

Eventhough the role of BRCA1/2 in hereditary prostatic cancer is being unleashed at a rapid rate; their optimal clinical management remains undefined. Cancer stem cells are thought to be responsible for cancer chemoresistance and relapse, thus they represent a significant concern for cancer prognosis and therapy. In this study, we have analyzed the effect of Plumbagin (PB) and structurally related naphthaquinones on BRCA1/2 silenced prostate cancer cells and the ability of PB to target stem cells. Our cell proliferation studies showed that both PC-3 and DU145 cells were more sensitive to PB, though all the compounds induced mitochondrial potential loss, DNA fragmentation and morphological changes which are indicative of apoptosis. Both BRCA1/2 siRNA transfected PC-3 and DU145 cells exhibited increased sensitivity to PB. Gene expression profiling post PB treatment in BRCA1/2 silenced cells revealed that PB has a putative role in tumor suppression in BRCA defective cancers. Using flow cytometric analysis we have proved that PB has the putative ability to directly target CSCs. Overall studies suggest that PB's antitumour mechanisms holds promise for novel therapeutic approaches against BRCA mutated cancers as well as CSCs.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Proteína BRCA1/genética , Proteína BRCA2/genética , Naftoquinonas/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Próstata/efeitos dos fármacos , Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia
12.
Reprod Domest Anim ; 51(6): 855-869, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27569719

RESUMO

The objective of this study was to document the expression and localization of angiopoietin (ANGPT) family members comprising of angiopoietin (ANGPT1 and ANGPT2), and their receptors (Tie1 and Tie2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle, and the modulatory role of ANGPT1 and ANGPT2 alone or in combinations on progesterone (P4 ) secretion and mRNA expression of phosphotidylinositide-3kinase-protein kinase B (PI3K-AKT), phosphoinositide-dependent kinase (PDK), protein kinase B (AKT), Bcl2 associated death promoter (BAD), caspase 3 and von willebrand factor (vWF) in luteal cells obtained from midluteal phase (MLP) of oestrous cycle in buffalo. Real-time RT-PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors whereas, the P4 secretion was assessed by RIA. The mRNA and protein expression of ANGPT1 and Tie2 was maximum (p < .05) in mid luteal phase (MLP) of oestrous cycle. The ANGPT2 mRNA and protein expression was maximum (p < .05) in early luteal phase, decreased in MLP and again increased in late luteal phase of oestrous cycle. ANGPT family members were localized in luteal cells and endothelial cells with a stage specific immunoreactivity. P4 secretion was highest (p < .05) with 100 ng/ml at 72 hr when luteal cells were treated with either protein alone. The mRNA expression of PDK, AKT and vWF was highest (p < .05) and BAD along with caspase 3 were lowest (p < .05) at 100 ng/ml at 72 hr of incubation period, when cultured luteal cells were treated with either protein alone or in combination. To conclude, our study explores the steroidogenic potential of angiopoietins to promote P4 secretion, luteal cell survival and angiogenesis through an autocrine and paracrine actions in buffalo CL.


Assuntos
Angiopoietinas/metabolismo , Búfalos/fisiologia , Corpo Lúteo/metabolismo , Ciclo Estral/fisiologia , Neovascularização Fisiológica/fisiologia , Progesterona/metabolismo , Angiopoietinas/genética , Animais , Western Blotting , Caspase 3/genética , Caspase 3/metabolismo , Sobrevivência Celular/fisiologia , Células Cultivadas , Feminino , Regulação da Expressão Gênica/fisiologia , Células Lúteas/fisiologia , Fosfatidilinositóis/genética , Fosfatidilinositóis/metabolismo , Progesterona/genética , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de TIE/genética , Receptores de TIE/metabolismo , Proteína de Morte Celular Associada a bcl/genética , Proteína de Morte Celular Associada a bcl/metabolismo , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo
13.
Mater Horiz ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884595

RESUMO

Electrochemical nitrate (NO3-) reduction to ammonia (NH3), which is a high value-added chemical or high-energy density carrier in many applications, could become a key process overcoming the disadvantages of the Haber-Bosch process; however, current electrocatalysts have severe drawbacks in terms of activity, selectivity, and stability. Here, we report the hydrogen radical (H*) pathway as a solution to overcome this challenge, as demonstrated by efficacious electrochemical NO3- reduction to NH3 over the Fe-polyoxometalate (Fe-POM)/Cu hybrid electrocatalyst. Fe-POM, composed of Preyssler anions ([NaP5W30O110]14-) and Fe cations, facilitates efficient H* generation via H2O + e- → H* + OH-, and H* transfer to the Cu sites of the Fe-POM/Cu catalyst enables selective NO3- reduction to NH3. Operando spectroelectrochemical spectra substantiate the occurrence of the H* pathway through direct observation of Fe redox related to H* generation and Cu redox related to NO3- binding. With the H* pathway, the Fe-POM/Cu electrodes exhibit high activity for NO3- reduction to NH3 with 1.44 mg cm-2 h-1 in a 500 ppm NO3-/1 M KOH solution at -0.2 V vs. RHE, which is about 36-fold higher than that of the pristine Cu electrocatalyst. Additionally, it attains high selectivity with a faradaic efficiency of up to 97.09% at -0.2 V vs. RHE while exhibiting high catalytic stability over cycles.

14.
Nat Commun ; 15(1): 1928, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431651

RESUMO

The molecule-metal interface is of paramount importance for many devices and processes, and directly involved in photocatalysis, molecular electronics, nanophotonics, and molecular (bio-)sensing. Here the photostability of this interface is shown to be sensitive even to room light levels for specific molecules and metals. Optical spectroscopy is used to track photoinduced migration of gold atoms when functionalised with different thiolated molecules that form uniform monolayers on Au. Nucleation and growth of characteristic surface metal nanostructures is observed from the light-driven adatoms. By watching the spectral shifts of optical modes from nanoparticles used to precoat these surfaces, we identify processes involved in the photo-migration mechanism and the chemical groups that facilitate it. This photosensitivity of the molecule-metal interface highlights the significance of optically induced surface reconstruction. In some catalytic contexts this can enhance activity, especially utilising atomically dispersed gold. Conversely, in electronic device applications such reconstructions introduce problematic aging effects.

15.
J Educ Health Promot ; 12: 49, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113438

RESUMO

BACKGROUND: The usage of smartphones has become common among adolescents, despite knowing the health-related problems of the user. Currently, the availability of electronic gadgets has become economical and this has an impact on society, especially on the behavior of adolescents. MATERIALS AND METHODS: A cross-sectional survey design was used to find the pattern of smartphone usage, smartphone addiction, and subjective health problems associated with smartphone usage. The data were obtained from 270 nursing students using the convenient sampling technique using a sociodemographic proforma, semi-structured questionnaire on the pattern of smartphone usage, Smartphone Addiction Scale, self-reported subjective health problems questionnaire, and study habits scale. STATISTICAL ANALYSIS: Descriptive and inferential statistics was used for the analysis using SPSS 16.0. RESULTS: The study findings revealed that most of the participants 243 (90.0%) were using 4G phones. The majority 88 (32.60%) of the participants were using a smartphone for less than 2 hours at a stretch in a day. Most uses of a smartphone were in the night 155 (57.40%). The main usage of a smartphone was for entertainment purposes 213 (78.90%). Most of the participants 196 (72.6%) were moderately addicted to smartphones. One-third 109 (40.2%) of the participants complained of headache, followed by straining of the eyes 83 (30.6%). CONCLUSION: The awareness of smartphone addiction and health-related problems associated with smartphone usage has been shown to decrease its impact. The study concluded that it is very much necessary to identify the pattern of smartphone usage, to prevent the consequences of addiction and health problems associated with smartphone usage.

16.
BMC Genomics ; 13: 455, 2012 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-22950736

RESUMO

BACKGROUND: For many analytical methods the efficiency of DNA amplification varies across the genome and between samples. The most affected genome regions tend to correlate with high C + G content, however this relationship is complex and does not explain why the direction and magnitude of effects varies considerably between samples. RESULTS: Here, we provide evidence that sequence elements that are particularly high in C + G content can remain annealed even when aggressive melting conditions are applied. In turn, this behavior creates broader 'Thermodynamically Ultra-Fastened' (TUF) regions characterized by incomplete denaturation of the two DNA strands, so reducing amplification efficiency throughout these domains. CONCLUSIONS: This model provides a mechanistic explanation for why some genome regions are particularly difficult to amplify and assay in many procedures, and importantly it also explains inter-sample variability of this behavior. That is, DNA samples of varying quality will carry more or fewer nicks and breaks, and hence their intact TUF regions will have different lengths and so be differentially affected by this amplification suppression mechanism - with 'higher' quality DNAs being the most vulnerable. A major practical consequence of this is that inter-region and inter-sample variability can be largely overcome by employing routine fragmentation methods (e.g. sonication or restriction enzyme digestion) prior to sample amplification.


Assuntos
Genoma Humano/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Composição de Bases/genética , Humanos
17.
J Biomol Struct Dyn ; 40(18): 8602-8614, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-33896364

RESUMO

A novel Schiff base was synthesized by the condensation of imidazole-2-carboxaldehyde with l-histidine in an equimolar ratio. The prepared Schiff base was characterized by elemental analysis and spectral characterization techniques. It was then complexed with a series of 3-d metal(II) ions like manganese, iron, cobalt, nickel, copper and zinc. The coordination properties, nature of bonding and stability of the complexes were deduced from elemental analysis, IR, UV-vis, 1H NMR, mass, electronic spectra, magnetic, conductivity and thermogravimetric analysis. IR studies support the tridentate behaviour of Schiff base as well as its coordination to the central metal ion through an azomethine nitrogen, deprotonated carboxylic oxygen and imidazole ring nitrogen atoms of histidine. The electronic spectra and magnetic moment data demonstrate that the complexes have an octahedral geometry, except zinc complex, which has a tetrahedral geometry. In vitro antimicrobial activity of the synthesized compounds has been shown to exhibit excellent antibacterial and antifungal activities. The antibacterial property of the prepared Schiff base was further confirmed by conducting a docking study of target proteins involved in the antibacterial mechanism.Communicated by Ramaswamy H. Sarma.


Assuntos
Complexos de Coordenação , Bases de Schiff , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Cobalto/química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cobre/química , Histidina , Imidazóis/farmacologia , Ferro , Ligantes , Manganês , Simulação de Acoplamento Molecular , Níquel/química , Nitrogênio , Oxigênio , Bases de Schiff/química , Bases de Schiff/farmacologia , Zinco/química
18.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 2): 3536-3540, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36160947

RESUMO

India was severely affected by the second wave of coronavirus disease (COVID­19), leading to sudden expansive spread of Mucormycosis, presenting with sinusitis, blackish mucus secretions, discolouration of palate, facial pain, swelling and blurring of vision. Hyperglycemia, hypercoagulable state and elevated levels of serum ferritin were the major contributing factors in progression of the deadly disease. To highlight the correlation between Diabetes Mellitus, hyperferritenimia and elevated levels of D-Dimer with increased rate of incidence and poor prognosis of the disease. This study was undertaken in KLES Dr Prabhakar Kore Hospital & MRC, Belagavi, including 30 patients, between April to July 2021. Serum ferritin, HbA1C and D-Dimer were evaluated for patients on admission, along with the other routine blood investigations. The mean age was 50 years (49.99 ± 1.8), with a male predominance of 83.33% (25 Male patients). 93.33% patients had uncontrolled Diabetes Mellitus with a mean value of 10.12% (± 0.37) indicating Diabetes Mellitus to be the prime risk factor. The raised levels of serum ferritin with a mean of 662.01 ng/ml (± 129.18) and high levels of D-Dimer (Mean- 761.33 ± 151.8 ng/ml) also demonstrated their role as interlinked factors. Mucor epidemic was caused by convergence of interlinked risk factors. Awareness of red flag clinical features, prompt diagnosis, early initiation of treatment with amphotericin-B with aggressive surgical debridement are essential for successful outcome, to avoid high rate of mortality and morbidity rates in the mucormycosis patients.

19.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 3): 5836-5840, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36742649

RESUMO

Necrotizing fasciitis is severe inflammation of the muscle sheath that leads to necrosis of the subcutaneous tissue and adjacent fascia. The disease entity is more commonly described in adults and the literature seems quite sparse with respect to children and even lesser in neonates. Monomicrobial infection with necrotizing fasciitis in Neck following insect bite is rare and even rarer in neonates. 07 day old neonate had history of rapid onset discoloration and swelling of the Right side of Neck following an insect bite which was followed fever and irritability and eventually black discoloration. The neonate was irritable with excessive crying, had tachycardia, tachypnea and was febrile. There was a diffuse swelling in the right side of neck with multiple patchy areas of tissue necrosis in form of blackening of the skin over the swelling Management: Necrotizing fasciitis was identified early and the neonate prepped for surgery. All the biochemical parameters were WNL. CRP was raised. Empirical treatment with Cefotaxime, Clindamycin and cloxacillin started and neonate taken for local debridement. All necrotic tissue was removed including tail of parotid. Over next 5 days serial debridement and wound wash with Hydrogen peroxidase, Betadine, saline and metronidazole was done. The edges of the wound became healthy with no new slough formation and necrotic tissue. An early diagnosis and definitive management with both surgery and antibiotics is the key to a reduce mortality in the neonates. It needs to be followed up with good local wound care.

20.
Energy Environ Sci ; 15(5): 1988-2001, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35706421

RESUMO

The operating conditions of low pH and high potential at the anodes of polymer electrolyte membrane electrolysers restrict the choice of catalysts for the oxygen evolution reaction (OER) to oxides based on the rare metals iridium or ruthenium. In this work, we investigate the stability of both the metal atoms and, by quantitative and highly sensitive 18O isotope labelling experiments, the oxygen atoms in a series of RuO x and IrO x electrocatalysts during the OER in the mechanistically interesting low overpotential regime. We show that materials based on RuO x have a higher dissolution rate than the rate of incorporation of labelled oxygen from the catalyst into the O2 evolved ("labelled OER"), while for IrO x -based catalysts the two rates are comparable. On amorphous RuO x , metal dissolution and labelled OER are found to have distinct Tafel slopes. These observations together lead us to a full mechanistic picture in which dissolution and labelled OER are side processes to the main electrocatalytic cycle. We emphasize the importance of quantitative analysis and point out that since less than 0.2% of evolved oxygen contains an oxygen atom originating from the catalyst itself, lattice oxygen evolution is at most a negligible contribution to overall OER activity for RuO x and IrO x in acidic electrolyte.

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