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1.
Discov Nano ; 19(1): 103, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884869

RESUMO

Graphene-based nanomaterials (graphene, graphene oxide, reduced graphene oxide, graphene quantum dots, graphene-based nanocomposites, etc.) are emerging as an extremely important class of nanomaterials primarily because of their unique and advantageous physical, chemical, biological, and optoelectronic aspects. These features have resulted in uses across diverse areas of scientific research. Among all other applications, they are found to be particularly useful in designing highly sensitive biosensors. Numerous studies have established their efficacy in sensing pathogens and other biomolecules allowing for the rapid diagnosis of various diseases. Considering the growing importance and popularity of graphene-based materials for biosensing applications, this review aims to provide the readers with a summary of the recent progress in the concerned domain and highlights the challenges associated with the synthesis and application of these multifunctional materials.

2.
Asian Pac J Cancer Prev ; 25(6): 1911-1920, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38918651

RESUMO

INTRODUCTION: Lung cancer is one of the commonest cause of cancer associated mortality worldwide. Platelets have emerged as key players in cancer development and progression by supporting tumor growth, and dissemination. In the present systematic review, we analyzed RNA transfer between cancer cells and platelets and explored potential role of different platelet RNA profiles as onco-signature in diagnosis, subtyping, disease progression and treatment monitoring in carcinoma lung carcinoma. MATERIALS AND METHODS: The study followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and Cochrane Manual of Systematic Reviews and Meta-analysis that included seven studies on patients with lung cancer, with data on tumor-educated platelets, and control group. The outcome measured was based on sensitivity, specificity, and ROC. PUBMED, SCOPUS, Central Cochrane Registry of Controlled Trials and Science Direct databases were searched using specific search terms until October 2023. QUADAS - 2 tool was used to assess quality, risk of bias and applicability concerns. RESULTS: The analysis revealed AUC > 70% for different platelet mRNAs, with sensitivity and specificity of more than 60 %. AUC and sensitivity were highest for ITGA2B (AUC 0.922; sensitivity 92.8%). lncRNA GTF2H2-1 was the most specific platelet RNA. On QUADAS-2 tool, 3/7 articles were unclear in reference standards, patient flow timing, and 1/7 had high bias in both aspects. For applicability, 1/7 studies were unclear in reference standards, and 2/7 in index tests. CONCLUSION: TEP RNA can aid in early diagnosis of lung cancer and of proven utility in its early-stage detection. TEP RNA can also monitor disease progression and treatment response.


Assuntos
Biomarcadores Tumorais , Plaquetas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Biomarcadores Tumorais/sangue , Plaquetas/patologia , Plaquetas/metabolismo , Prognóstico , RNA Longo não Codificante/genética , RNA Longo não Codificante/sangue
3.
J Neurosci Rural Pract ; 15(2): 182-193, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38746499

RESUMO

Memory deficits are observed across psychiatric disorders ranging from the prodrome of psychosis to common mental disorders such as anxiety, depression, and dissociative disorders. Memory deficits among patients recovering from psychiatric disorders could be directly related to the primary illness or secondary to the adverse effect of a treatment such as Electroconvulsive Therapy (ECT). The trouble in the meaningful integration of working-memory and episodic memory is the most commonly affected domain that requires routine assessments. An update on the recent trends of methods of assessment of memory deficits is the first step towards understanding and correcting these deficits to target optimum recovery. A systematic literature search was conducted from October 2018 to October 2022 to review the recent methods of assessment of memory deficits in psychiatric disorders. The definition of 'Memory deficit' was operationalized as 'selective processes of memory, commonly required for activities of daily living, and affected among psychiatric disorders resulting in subjective distress and dysfunction'. We included 110 studies, most of them being conducted in western countries on patients with schizophrenia. Other disorders included dementia and mild cognitive impairment. Brief Assessment of Cognition in Schizophrenia, Cambridge Automated Neuropsychological Test Battery, California Verbal Learning Test, Trail Making Test Part A and B, Rey Auditory Verbal Learning Test, Wechsler Memory Scale, Wechsler Adults Intelligence Scale-IV were the most common neuropsychological assessments used. Mini-Mental State Examination and Montreal Cognitive Assessment were the most common bedside assessment tools used while Squire Subjective Memory Questionnaire was commonly used to measure ECT-related memory deficits. The review highlights the recent developments in the field of assessment of memory deficits in psychiatric disorders. Findings recommend and emphasize routine assessment of memory deficits among psychiatric disorders in developing countries especially severe mental illnesses. It remains interesting to see the role of standardized assessments in diagnostic systems given more than a decade of research on memory deficits in psychiatric disorders.

4.
Nanoscale ; 16(20): 9642-9658, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38644768

RESUMO

Silver Cluster-Assembled Materials (SCAMs) represent a new frontier of crystalline extended solids hallmarked by their customizable structures, commendable stabilities, and unique physical/chemical properties. Since their discovery in 2017, the diversity of organic linkers has endowed SCAMs with ingenious architectures and the application scenario has expanded beyond photoluminescence sensing to environmental sustainability and biomedical applications. It is critically important to chronicle these recent key advances and review the progress of SCAMs that can enable translating the material discoveries into real implementation. Herein, we provide a succinct overview of the trajectory of SCAM research, with crucial insights into atomic-level structural correlations with the phenomena at the nanoscale and discuss the gaps and opportunities that are still open in addition to charting a roadmap for future research directions.

5.
J Neurosci Rural Pract ; 15(1): 16-28, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476438

RESUMO

Objectives: D-dimer levels are increased in stroke and cancer. Cancer patients are at a higher risk of stroke. However, the evidence is unclear if high D-dimer in stroke patients can suggest the diagnosis of concomitant cancer or the development of stroke in a cancer patient. The objective is to assess the evidence available on the baseline D-dimer level in stroke patients with and without cancer. Materials and Methods: We conducted the systematic review and meta-analysis using the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We searched PUBMED, Cochrane, ScienceDirect, and Scopus for potentially eligible articles published till June 2023. All the review steps were iterative and done independently by two reviewers. The Newcastle-Ottawa scale tool was used to assess the quality of included studies for case control and cohort studies and the Agency for Healthcare Research and Quality tool for cross-sectional studies. The qualitative synthesis is presented narratively, and quantitative synthesis is shown in the forest plot using the random effects model. I2 of more than 60% was considered as high heterogeneity. Results: The searches from all the databases yielded 495 articles. After the study selection process, six papers were found eligible for inclusion in the qualitative and quantitative synthesis. In the present systematic review, 2651 patients with ischemic infarcts are included of which 404 (13.97%) patients had active cancer while 2247 (86.02%) did not. The studies included were of high quality and low risk of bias. There were significantly higher baseline D-dimer levels in stroke patients with cancer than in non-cancer patients with a mean difference of 4.84 (3.07-6.60) P < 0.00001. Conclusion: D-dimer is a simple and relatively non-expensive biomarker that is increased to significant levels in stroke patients, who have cancer and therefore may be a tool to predict through screening for active or occult cancer in stroke patients.

6.
J Environ Manage ; 354: 120261, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354608

RESUMO

The future of reactive nitrogen (N) for subtropical lowland rice to be characterised under diverse N-management to develop adequate sustainable practices. It is a challenge to increase the efficiency of N use in lowland rice, as N can be lost in various ways, e.g., through nitrous oxide (N2O) or dinitrogen (N2) emissions, ammonia (NH3) volatilization and nitrate (NO3-) leaching. A field study was carried out in the subsequent wet (2021) and dry (2022) seasons to assess the impacts of different N management strategies on yield, N use efficiency and different N losses in a double-cropped rice system. Seven different N-management practices including application of chemical fertilisers, liquid organic fertiliser, nitrification inhibitors, organic nutrient management and integrated nutrient management (INM) were studied. The application of soil test-based neem-coated urea (NCU) during the wet season resulted in the highest economic yield, while integrated nutrient management showed the highest economic yield during the dry season. Total N losses by volatilization of NH3, N2O loss and leaching were 0.06-4.73, 0.32-2.14 and 0.25-1.93 kg ha-1, corresponding to 0.06-5.84%, 0.11-2.20% and 0.09-1.81% of total applied N, respectively. The total N-uptake in grain and straw was highest in INM (87-89% over control) followed by the soil test-based NCU (77-82% over control). In comparison, recovery efficiency of N was maximum from application of NCU + dicyandiamide during both the seasons. The N footprint of paddy rice ranged 0.46-2.01 kg N-eq. t-1 during both seasons under various N management. Ammonia volatilization was the process responsible for the largest N loss, followed by N2O emissions, and NO3- leaching in these subtropical lowland rice fields. After ranking the different N management practices on a scale of 1-7, soil test-based NCU was considered the best N management approach in the wet year 2021, while INM scored the best in the dry year 2022.


Assuntos
Oryza , Nitrogênio/análise , Agricultura/métodos , Amônia/análise , Solo , Fertilizantes/análise , Óxido Nitroso/análise
7.
Small ; 20(20): e2307666, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38279566

RESUMO

Discovery of new topology covalent organic frameworks (COFs) is a mainstay in reticular chemistry and materials research because it not only serves as a stepwise guide to the designed construction of covalent-organic architectures but also helps to comprehend function from structural design point-of-view. Proceeding on this track, the first 3D COF, TUS-38, with the topology is constructed by reticulating a planar triangular 3-c node of D3h symmetry with a tetragonal prism 8-c node of D2h symmetry via [3 + 8] reversible imine condensation reaction. TUS-38 represents a twofold interpenetrated multidirectional pore network with a high degree of crystallinity and structural integrity. Interestingly, stemming from the nitrogen-rich s-triazine rings with electron-deficient character and ─C â• N─ linkages composing the TUS-38 framework that benefit to the charge-transfer and hence dipole-dipole electrostatic interactions between the framework and iodine in addition to exclusive topological characteristics of the exotic the net, TUS-38 achieves an exemplary capacity for iodine vapor uptake reaching 6.3 g g-1. Recyclability studies evidence that TUS-38 can be reused at least five times retaining 95% of its initial adsorption capacity; while density functional theory (DFT) calculations have heightened the understanding of the interactions between iodine molecules and the framework.

8.
J Biomed Opt ; 29(1): 017002, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38213472

RESUMO

Significance: The photoacoustic (PA) technique, a noninvasive pump-probe technique, has found interesting applications in biomedical tissue diagnosis over the last decade. To take it a step further to clinical applications, the PA technique needs to be designed as an instrument focusing on a compact design, reducing the cost, and quickly providing a quantitative diagnosis. Aim: This work presents a design and characterization of a cost-effective, compact PA sensing instrument for biomedical tissue diagnosis. Approach: A compact laser diode case design is developed to house several laser diodes for PA excitation, and a pulsed current supply unit is also developed in-house to power the laser diodes to generate a 25 ns current pulse at a frequency of 20 kHz. After PA experimental data acquisition, the signal's frequency spectra were calculated to characterize the tissue quantitatively and correlated with their mechanobiological properties. Results: The corresponding dominant frequency peak in the PA spectral response (PASR) study was low in the fibrofatty normal breast tissue 0.26±0.03 MHz, compared to the dominant frequency peak of 1.60±0.016 MHz in the fibrocystic disease tissue, which had increased glandular and stromal elements, thereby increased tissue density. The histopathological findings correlated with the PASR results, and the fibrocystic breast disease tissue exhibited a higher dominant frequency peak and energy compared to the normal breast tissue. Conclusions: We experimented with an in vitro PASR study of fibrocystic human breast tissues and successfully differentiated different tissue types using quantitative spectral parameters peak frequency, mean frequency, and spectral energy. This gives the potential to take this technique further for cost-effective and quick clinical applications.


Assuntos
Lasers Semicondutores , Técnicas Fotoacústicas , Humanos , Análise Custo-Benefício , Análise Espectral , Técnicas Fotoacústicas/métodos
9.
Small ; 20(2): e2304210, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37626458

RESUMO

Due to their high designability, unique geometric and electronic structures, and surface coordination chemistry, atomically precise metal nanoclusters are an emerging class of functional nanomaterials at the forefront of materials research. However, the current research on metal nanoclusters is mainly fundamental, and their practical applications are still uncharted. The surface binding properties and redox activity of Au24 Pt(PET)18 (PET: phenylethanethiolate, SCH2 CH2 Ph) nanoclusters are herein harnessed as an high-efficiency electrocatalyst for the anchoring and rapid conversion of lithium polysulfides in lithium-sulfur batteries (LSBs). Au24 Pt(PET)18 @G composites are prepared by using the large specific surface area, high porosity, and conductive network of graphene (G) for the construction of battery separator that can inhibit polysulfide shuttle and accelerate electrochemical kinetics. Resultantly, the LSB using a Au24 Pt(PET)18 @G-based separator presents a high reversible specific capacity of 1535.4 mA h g-1 for the first cycle at 0.2 A g-1 and a rate capability of 887 mA h g-1 at 5 A g-1 . After 1000 cycles at 5 A g-1 , the capacity is 558.5 mA h g-1 . This study is a significant step toward the application of metal nanoclusters as optimal electrocatalysts for LSBs and other sustainable energy storage systems.

10.
Chemistry ; 30(6): e202303474, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38078517

RESUMO

The implacable rise of carbon dioxide (CO2 ) concentration in the atmosphere and acute water stress are one of the central challenges of our time. Present-day chemistry is strongly inclined towards more sustainable solutions. Covalent organic frameworks (COFs), attributable to their structural designability with atomic precision, functionalizable chemical environment and robust extended architectures, have demonstrated promising performances in CO2 trapping and water harvesting from air. In this Review, we discuss the major developments in this field as well as sketch out the opportunities and shortcomings that remain over large-scale COF synthesis, device engineering, and long-term performance in real environments.

11.
J Neurosci Rural Pract ; 14(4): 593-598, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38059255

RESUMO

Pineal cysts are usually benign, fluid-filled sacs and most pineal cysts are asymptomatic. Sudden death specifically related to pineal cysts is extremely uncommon. A literature review of the pertinent databases, including PubMed, Google Scholar, Scopus, and Web of Science, was carried out to review the existing literature describing sudden death in patients with pineal cysts. In the evaluation of 49 articles, it was found that four reports discussed the unexpected death of patients who had pineal cysts. A total of four cases of sudden death and a pineal cyst were reported. There were 75% females and a mean age of 29 (range: 20-45). Cyst size on average was 1.3 cm (1.2-1.5). In each case, the cause of death and the involvement of important brain structures were confirmed by autopsy results. A pathological analysis of the pineal region and the surrounding brain tissue revealed a variety of lesions. Vascular malformation was found in one case, adding another layer of complexity to the study of sudden death syndrome. In this research, the authors highlight the fact that patients with pineal cysts can experience serious, even fatal, complications. Increased vigilance and early detection through neuroimaging and neurological assessments are required due to the wide variety of clinical manifestations and underlying mechanisms. To explain the mechanism and enhance the management and prevention of sudden deaths associated with pineal cysts, additional research with larger sample sizes is required.

12.
PLoS One ; 18(12): e0295679, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38128032

RESUMO

This work focuses on the utilization of counter-propagating plane waves for optical manipulation, which provides a unique approach to control the behavior of Rayleigh and Dipolar nanoparticles immersed in a homogeneous or heterogeneous medium. Our study presents an interesting finding of a repulsive force between plasmonic-chiral heterodimers where the particles move away from each other in both near and far field regions. Interestingly, this repulsive thrust supports the wave like nature of light for the case of homogeneous background but particle type nature of light for heterogenous background. At first, we have investigated the theory underlying the optical trapping of the chiral particle and the impact of this phenomenon on the overall repulsive behavior of the heterodimers placed in air (homogeneous) background. After that, our proposed set-up has further been investigated putting in air-water interface (heterogenous background) and by varying light angle only a little bit. Our observation for this interface case is suggesting the transfer of Minkowski momentum of photon to each optically pulled Rayleigh or dipolar particle of the dimer set, which ultimately causes a broad-band giant repulsive thrust of the dimers. However, in absence of the other particle in the cluster, a single half-immersed particle does not experience the pulling force for the broad-band spectrum. The 'common' reason of the observed repulsive thrust of the dimers for both the aforementioned cases has been attributed to "modified" longitudinal Optical Binding Force (OBF). Technically, this work may open a new way to control the repulsion and attraction between the nanoparticles both in near and far field regions by utilizing the background and the counter-propagating waves. We also believe that this work manifests a possible simple set-up, which will support to observe a background dependent wave 'or' particle nature of light experimentally.


Assuntos
Nanopartículas , Pinças Ópticas
13.
Ann Neurosci ; 30(4): 251-255, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38020397

RESUMO

Ewing's Sarcomas (ES)/Peripheral neuroectodermal tumour (pPNET) are heterogenous group of rare, highly malignant, undifferentiated primitive round-cell neoplasms of neuroectodermal origin. pPNETs are seldom observed to involve the spine of which Spinal Intradural Extramedullary Extraosseous Primary ES/pPNET are extremely rare. We report a case of a 23-year-old male with complaints of low backache and hip pain radiating to the left inguinal region for four months. Radiology findings were suggestive of a neurogenic tumour. Cytomorphology, histomorphology and immunohistochemistry evaluation were done. Diagnosis was consistent with ES/pPNET. Careful correlation between clinical history, cytomorphology, histopathology, immunohistochemical and molecular analysis can help to distinguish primary spinal ES/PNET from other primary spinal tumours and will help clinicians to start treatment at the earliest.

15.
Nanoscale ; 15(40): 16299-16306, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37718910

RESUMO

Silver cluster-assembled materials (SCAMs) have garnered significant interest as promising platforms for different functional explorations. Their atomically precise structures, intriguing chemical/physical properties, and remarkable luminescent capabilities make them highly appealing. However, the properties of these materials are primarily determined by their structural architecture, which is heavily influenced by the linker molecules used in their assembly. The choice of linker molecules plays a pivotal role in shaping the structural characteristics and ultimately determining the unique properties of SCAMs. To this end, the first SCAM with an intriguing (3,6)-connected kgd topology, [Ag12(StBu)6(CF3COO)6(TPBTC)6]n (termed TUS 3), TPBTC = benzene-1,3,5-tricarboxylic acid tris-pyridin-4-ylamide, has been synthesized by reticulating C6-symmetric Ag12 cluster cores with C3-symmetric tripodal pyridine linkers. Due to the structutural architecture of the linker molecule, TUS 3 posseses a luminescent porous framework structure where each two-dimensional (2D) layers are non-covalently linked with each other to form a three dimensional (3D) framework and ultimately offers uniaxial open channels. The compact mesoporous structural architecture not only gives the excellent surface area but also offers impressive stability of this material even in water medium. Taking advantage of these properties, TUS 3 shows brilliant catalytic activity in the reduction of hexacyanoferrate(III) using sodium borohydride in aqueous solutions.

17.
Nanoscale Horiz ; 8(11): 1509-1522, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37772632

RESUMO

The quest for cleaner pathways to the production of fuels and chemicals from non-fossil feedstock, efficient transformation of raw materials to value-added chemicals under mild conditions, and control over the activity and selectivity of chemical processes are driving the state-of-the-art approaches to the construction and precise chemical modification of sustainable nanocatalysts. As a burgeoning category of atomically precise noble metal nanoclusters, copper nanoclusters (Cu NCs) benefitting from their exclusive structural architecture, ingenious designability of active sites and high surface-to-volume ratio qualify as potential rationally-designed catalysts. In this Minireview, we present a detailed coverage of the optimal design strategies and controlled synthesis of Cu NC catalysts with a focus on tuning of active sites at the atomic level, the implications of cluster size, shape and structure, the ligands and heteroatom doping on catalytic activity, and reaction scope ranging from chemical catalysis to emerging photocatalysis and electrocatalysis.

18.
Environ Monit Assess ; 195(9): 1099, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37632560

RESUMO

Mitigating the atmospheric greenhouse effect while enhancing the inherent soil quality and productive capacity is possible through soil carbon (C) sequestration, which has a significant potential to counteract the adverse effects of agroecosystem level C emission through natural and anthropogenic means. Although rice is the most important food in India, feeding more than 60% of the country's population, it is commonly blamed for significant methane (CH4) emissions that accelerate climate change. Higher initial soil organic matter concentrations would create more CH4 under the flooded soil conditions, as reducible soil C is a prerequisite for CH4 generation. In India, rice is generally cultivated in lowlands under continuous flooding. Less extensive organic matter breakdown in lowland rice agroecosystems often significantly impacts the dynamics of soil active and passive C pools. Change from conventional to conservation agriculture might trap a significant quantity of SOC. The study aims to investigate the potential of rice-based soils to sequester C and reduce the accelerated greenhouse effects through modified farming practices, such as crop residue retention, crop rotation, organic farming, varietal selection, conservation agriculture, integrated nutrient management, and water management. Overall, lowland rice agroecosystems can sequester significant amounts of SOC, but this potential must be balanced against the potential for CH4 emissions. Management practices that reduce CH4 emissions while increasing soil C sequestration should be promoted and adopted to maximize the sustainability of rice agroecosystems. This review is important for understanding the effectiveness of the balance between SOC sequestration and CH4 emissions in lowland rice agroecosystems for adopting sustainable agricultural practices in the context of climate change.


Assuntos
Oryza , Solo , Carbono , Sequestro de Carbono , Monitoramento Ambiental , Metano
19.
Dalton Trans ; 52(33): 11581-11590, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37548356

RESUMO

A pentadentate Cu(II) complex, [CuII(dpaq)](ClO4) (1), featuring a redox active ligand, H-dpaq (H-dpaq = 2-[bis(pyridine-2-ylmethyl)]amino-N-quinolin-8-yl-acetamidate), catalyses four-electron reduction of dioxygen by decamethylferrocene (Fc*) in the presence of trifluoroacetic acid (CF3COOH) in acetone at 298 K. No catalytic oxygen reduction was observed in the presence of stronger Brønsted acids than CF3COOH, such as perchloric acid (HClO4) or trifluoromethanesulphonic acid (HOTf). In contrast, facile catalytic reduction of O2 occurs by Fc* with 1 and HClO4 or HOTf in dimethylformamide (DMF). The use of CF3COOH as the proton source in DMF results in the suppression of O2 reduction under otherwise identical reaction conditions. While the O2 reduction reactions in DMF are linearly dependent on the pKa of Brønsted acids, the acid dependence on catalytic O2-reduction reactivity by 1 in acetone showed complete reversal. Cyclic voltammetry studies using p-chloranil as the probe substrates in the presence of acids in the solvents reveal that the strengths of the protonic acids increase significantly in acetone compared to that in DMF. The amidate-N in [CuII(dpaq)](ClO4) (1) undergoes protonation in the presence of HClO4 or HOTf in DMF to form [CuII(H-dpaq)]2+ (1-H+), but not in the presence of CF3COOH. Enhanced acid strength of CF3COOH in acetone, however, effectively protonates 1 and triggers O2 reduction. Protonation of 1 with HClO4 or HOTf in acetone results in the change of its coordination environment, and this protonated species does not trigger O2 reduction. Detailed kinetic studies indicate that 1-H+ undergoes reduction by two-electrons and the reduced species binds O2 to form a Cu(II)-superoxo intermediate. This is followed by a rate-determining proton-coupled electron-transfer (PCET) reduction to generate the Cu(II)-hydroperoxo intermediate. While catalytic O2 reduction in acetone occurs predominantly via a 4e-/4H+ pathway, product selectivity (H2O vs. H2O2) in DMF depends upon the concentration of the reductant (Fc*). While dioxygen reduction to H2O2 is favoured at low [Fc*], mechanistic studies suggest that O2 reduction with high [Fc*] proceeds via a [2e- + 2e-] mechanism, where the released H2O2 during catalysis is further reduced to water.

20.
Cancer Biomark ; 38(2): 203-214, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545224

RESUMO

BACKGROUND: miRNAs play a crucial role in the genesis of cancer, either as tumor suppressor genes or as oncogenes. Single Nucleotide Polymorphisms (SNPs) in the seed region of microRNAs (miRNAs) can dysregulate their levels in the tissues and thereby affect carcinogenesis. The association of SNP in miR-146a (rs2910164) with the risk of oral squamous cell carcinoma (OSCC) has not been understood. OBJECTIVE: In the present study, we have determined the association and functional significance of miR-146a (rs2910164) SNP with susceptibility to OSCC predisposition. METHODS: In the present case-control study, we enrolled 430 subjects from central India (215 OSCC cases and 215 healthy controls). We performed genotyping by Kompetitive Allele Specific PCR (KASP), and their correlation with OSCC susceptibility was analyzed. miRNA expression profiling in tumor tissues and adjacent normal tissues from six OSCC patients was done by a NanoString n-Counter-based assay. Subsequently, gene ontology and pathway analysis were performed with FunRich version 3.13. RESULTS: The CC genotype of rs2910164 miR-146a was significantly associated with the increased risk for OSCC (CC vs GC, OR = 2.62; 95% CI: 1.48-4.66; p value = 0.001). However, the GC genotype was protective with GC vs CC (OR = 0.38, 95%CI =0.21-0.67, p-value = 0.001), and GC vs GG (OR = 0.58, 95%CI = 0.37-0.89, p-value = 0.01). CONCLUSION: Our finding suggests that SNP rs2910164 of miR-146a may be a genetic risk factor for OSCC susceptibility in the Central India population. However, more extensive multicenter studies are required to validate these findings.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , MicroRNAs , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Neoplasias Bucais/genética , MicroRNAs/genética , Genótipo , Estudos de Casos e Controles
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