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1.
Philos Trans A Math Phys Eng Sci ; 382(2272): 20230220, 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38679049

RESUMEN

We present the formation of quasi-periodic cool spicule-like jets in the solar atmosphere using 2.5-D numerical simulation in two-fluid regime (ions+neutrals) under the presence of thermal conduction and ion-neutral collision. The nonlinear, impulsive Alfvénic perturbations at the top of the photosphere trigger field aligned magnetoacoustic perturbations due to ponderomotive force. The transport of energy from Alfvén pulse to such vertical velocity perturbations due to ponderomotive force is considered as an initial trigger mechanism. Thereafter, these velocity perturbations steepen into the shocks followed by quasi-periodic rise and fall of the cool jets transporting mass in the overlying corona. This article is part of the theme issue 'Partially ionized plasma of the solar atmosphere: recent advances and future pathways'.

2.
Mol Neurobiol ; 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38228842

RESUMEN

The iPSC-derived 3D models are considered to be a connective link between 2D culture and in vivo studies. However, the sensitivity of such 3D models is yet to be established. We assessed the sensitivity of the hiPSC-derived 3D spheroids against 2D cultures of neural progenitor cells. The sub-toxic dose of Sodium Arsenite (SA) was used to investigate the alterations in miRNA-proteins in both systems. Though SA exposure induced significant alterations in the proteins in both 2D and 3D systems, these proteins were uncommon except for 20 proteins. The number and magnitude of altered proteins were higher in the 2D system compared to 3D. The association of dysregulated miRNAs with the target proteins showed their involvement primarily in mitochondrial bioenergetics, oxidative and ER stress, transcription and translation mechanism, cytostructure, etc., in both culture systems. Further, the impact of dysregulated miRNAs and associated proteins on these functions and ultrastructural changes was compared in both culture systems. The ultrastructural studies revealed a similar pattern of mitochondrial damage, while the cellular bioenergetics studies confirm a significantly higher energy failure in the 2D system than to 3D. Such a higher magnitude of changes could be correlated with a higher amount of internalization of SA in 2D cultures than in 3D spheroids. Our findings demonstrate that a 2D culture system seems better responsive than a 3D spheroid system against SA exposure.

3.
Med J Armed Forces India ; 79(Suppl 1): S385-S386, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38144632
4.
Heliyon ; 9(11): e21701, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38027742

RESUMEN

Nowadays, the toxicity of lead in metal-halide perovskites is the most precarious obstruction in the commercialization of perovskite-based optoelectronic devices. However, Pb-free metal halide perovskites as environment-friendly materials because of their exceptional properties, such as band-gap tunability, narrow emission spectra, low toxicity and easy solution-processability, are potential candidates for optoelectronic applications. Recently, literature reported the poor structural stability and low-emission intensity of Bi-based perovskite NCs. Still, this paper focuses on the fabrication of Formamidinium (FA)-based Bi mixed halide and Methylammonium(MA)-based Bi-pure halide perovskites using Ligand-Assisted Reprecipitation Technique (LARP) technique. XRD diffraction patterns of FA-based perovskites were slightly broad, signifying the nanocrystalline form and limited size of perovskite nanocrystals. While the XRD diffraction patterns of MA3Bi2X9 (X = Cl/Br/I) perovskites were narrow, signifying the amorphous nature and larger size of perovskite nanocrystals. The peak positions were varied in MA-based bismuth halide perovskites with respect to the halide variation from Br to Cl to I ions. The optical study shows the variation in band gap and average lifetime with respect to halide variation leading to enhanced optical properties for device applications. The band-gap of FA3Bi2BrxCl1-x & FA3Bi2IxCl1-x perovskites was calculated to be around 3.7 & 3.8 eV, respectively, while in MA-halide perovskites the band-gap was calculated to be 2.8 eV, 3.1 eV & 3.4 eV with respect to halide variation from I to Cl to Br in perovskite samples using Tauc's plot respectively. Moreover, simulation is carried out using the SCAPS-1D software to study the various parameters in MA & FA-based Bi-pure or mixed halide perovskites. Here, we discussed the variation in efficiency with respect to the thickness variation from 100 to 500 nm for MA3Bi2I9 halide perovskites. These MA3Bi2I9 halide perovskites show minimum efficiency of 4.65 % at 100 nm thickness, while the perovskite sample exhibits maximum efficiency of 10.32 % at 500 nm thickness. Thus, the results stated that the thickness of absorber layers directly affects the device characteristics for optoelectronic applications.

5.
Indian J Pharmacol ; 55(2): 108-118, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37313936

RESUMEN

BACKGROUND AND OBJECTIVES: Induced pluripotent stem cells (iPSCs) derived three-dimensional (3D) model for rare neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS) is emerging as a novel alternative to human diseased tissue to explore the disease etiology and potential drug discovery. In the interest of the same, we have generated a TDP-43-mutated human iPSCs (hiPSCs) derived 3D organoid model of ALS disease. The high-resolution mass spectrometry (MS)-based proteomic approach is used to explore the differential mechanism under disease conditions and the suitability of a 3D model to study the disease. MATERIALS AND METHODS: The hiPSCs cell line was procured from a commercial source, grown, and characterized following standard protocols. The mutation in hiPSCs was accomplished using CRISPR/Cas-9 technology and predesigned gRNA. The two groups of organoids were produced by normal and mutated hiPSCs and subjected to the whole proteomic profiling by high-resolution MS in two biological replicates with three technical replicas of each. RESULTS: The proteomic analysis of normal and mutated organoids revealed the proteins associated with pathways of neurodegenerative disorders, proteasomes, autophagy, and hypoxia-inducible factor-1 signaling. Differential proteomic analysis revealed that the mutation in TDP-43 gene caused proteomic deregulation, which impaired protein quality mechanisms. Furthermore, this impairment may contribute to the generation of stress conditions that may ultimately lead to the development of ALS pathology. CONCLUSION: The developed 3D model represents the majority of candidate proteins and associated biological mechanisms altered in ALS disease. The study also offers novel protein targets that may uncloud the precise disease pathological mechanism and be considered for future diagnostic and therapeutic purposes for various neurodegenerative disorders.


Asunto(s)
Esclerosis Amiotrófica Lateral , Células Madre Pluripotentes Inducidas , Humanos , Proteoma , Esclerosis Amiotrófica Lateral/diagnóstico , Esclerosis Amiotrófica Lateral/genética , Proteómica , Diagnóstico Precoz , Proteínas de Unión al ADN , Organoides
6.
3 Biotech ; 13(5): 147, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37124988

RESUMEN

Carbon in many different forms especially, Graphene, Carbon nanotubes (CNTs), and Fullerene is emerging as an important material in the areas of the biomedical field for various applications. This review comprehensively describes the nano antibiotic effect of carbon-based nanocomposites: epicenter on graphene, carbon nanotubes, and fullerene Composites. It summarises the studies conducted to evaluate their antimicrobial applications as they can disrupt the cell membrane of bacteria resulting in cell death. The initial section gives a glimpse of both "Gram"-positive and negative bacteria, which have been affected by Graphene, CNTs, and Fullerene-based nanocomposites. These bacteria include Staphylococcus Aureus, Bacillus Thuringiensis, Enterococcus faecalis, Enterococcus faecium, Bacillus subtilis, Escherichia coli, Klebseilla pneumoniae, Pseudomonas aeroginosa, Pseudomonas syringae , Shigella flexneri,Candida Albicans, Mucor. Another section is dedicated to the insight of Graphene, and its types such as Graphene Oxide (GO), Reduced graphene oxide (rGO), Graphene Nanoplatelets (GNPs), Graphene Nanoribbons (GNRs), and Graphene Quantum Dots (GQDs). Insight into CNT, including both the types SWCNT and MWCNT, studied, followed by understanding fullerene is also reported. Another section is dedicated to the antibacterial mechanism of Graphene, CNT, and Fullerene-based nanocomposites. Further, an additional section is dedicated to a comprehensive review of the antibacterial characteristics of Graphene, CNT, and nanocomposites based on fullerene. Future perspectives and recommendations have also been highlighted in the last section.

7.
Biomass Convers Biorefin ; : 1-27, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36817514

RESUMEN

Bamboo, the fastest-growing plant, has several unique characteristics that make it appropriate for diverse applications. It is low-cost, high-tensile, lightweight, flexible, durable, and capable of proliferating even in ineffectual areas (e.g., incline). This review discusses the unique properties of bamboo for making charcoal and biochar for diverse applications. To produce bamboo charcoal and biochar, this study reports on the pyrolysis process for the thermal degradation of organic materials in an oxygen-depleted atmosphere under a specific temperature. This is an alternative method for turning waste biomass into products with additional value, such as biochar. Due to various advantages, bamboo charcoal is preferred over regular charcoal as it has four times the absorption rate and ten times more surface area reported. According to the reports, the charcoal yield ranges from 24.60 to 74.27%. Bamboo chopsticks were the most useful source for producing charcoal, with a high yield of 74.27% at 300 °C in nitrogen, but the thorny bamboo species have a tremendous amount of minimal charcoal, i.e., 24.60%. The reported biochar from bamboo yield ranges from 32 to 80%. The most extensive biochar production is produced by the bamboo D. giganteus, which yields 80% biochar at 300 °C. Dry bamboo stalks at 400 °C produced 32% biochar. One of the sections highlights biochar as a sustainable solution for plastic trash management produced during the COVID-19 pandemic. Another section is dedicated to the knowledge enhancement about the broad application spectrum of the charcoal and biochar. The last section highlights the conclusions, future perspectives, and recommendations on the charcoal and biochar derived from bamboo.

8.
Environ Technol ; 44(3): 416-430, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34433389

RESUMEN

This work reports the preparation of nano lignin-rich fraction material via green technology from the holistic use of lignocellulosic biomass bamboo. The bamboo is first chemically treated, followed by acid precipitation to extract bamboo-derived macro lignin-rich fraction material. The nano lignin-rich fraction material was then prepared via ultrasonication technique from the extracted bamboo-derived macro lignin-rich fraction material. The confirmation of the distinct lignin functional groups in the extracted lignin-rich fractions has been done by FTIR. Surface morphology by FESEM and TEM revealed spherical nano-lignin-rich fraction materials from extracted bamboo-derived macro lignin-rich fraction materials. DPPH assays indicated that both the obtained fractions depict beneficial antioxidant characteristics. They were found to be effective in terms of their antibacterial activity against both gram-positive bacteria Staphylococcus aureus (S.aureus) and gram-negative bacteria Escherichia coli (E.coli), using the disc diffusion method. These fractions have UV blocking property, and nano-lignin-rich fraction material acts as a more potential UV blocking agent than others. Thus, the nano-lignin-rich fraction material has great potential as a high antioxidant, antibacterial, and UV blocking agent useful in biomedical applications.Highlights Extraction of macro-lignin rich fraction material using chemical treatment of lignocellulosic biomass bamboo via refluxing followed by acid precipitation.Preparation of nano-lignin rich fraction material from extracted bamboo-derived macro-lignin rich fraction material via ultrasonication technique as a green technology.Structural and surface morphology of the extracted macro-lignin & nano lignin-rich fraction materials have been analyzed by XRD, FTIR, EDX, SEM and TEM.The macro lignin & nano lignin-rich fraction materials showed good antioxidant, antibacterial activity and UV-blocking properties, but the nano-lignin rich fraction material exhibited more efficient properties.


Asunto(s)
Antioxidantes , Lignina , Antioxidantes/farmacología , Lignina/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antibacterianos/farmacología , Antibacterianos/química , Escherichia coli
9.
Nanoscale Adv ; 4(13): 2902-2912, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-36131997

RESUMEN

Variation in the transmitted light intensity from metal oxide thin films with moisture content provides a great opportunity to use them for humidity sensing. Herein, we have developed a novel and simple humidity sensor based on ZnO nanorod (ZNR) thin films which work as transmission-based sensing elements in an in-house fabricated sensing setup. The ZNR sensing element shows excellent linear sensing performance in the relative humidity (RH) range 10-90% and does not show any hysteresis. A maximum change in optical power of ∼95 µW is observed with the change in RH in the range 10-90%, for the sample with the smallest crystallite size (ZNR1) and highest pore diameter of the ZNR film. Also, a maximum sensitivity of 1.104 µW/% RH is observed for the ZNR1 sample which drops to 0.604 µW/% RH for the highest crystallite size sample (ZNR4). The presence of oxygen vacancies and the micro-porous nature of the film allow the absorption of water vapour on the film which deflects light at different angles that vary with the moisture content. The experimental results suggest that the ZNR film with a smaller crystallite size and larger pore diameter is more sensitive for humidity measurements. Further, an improved sensing performance is perceived in ZNRs because of the larger surface area of the nanorods. The ZNR based sensing elements do not suffer from ageing effects and exhibit high repeatability (88.74%). Further, the humidity sensor has a response time of 62 seconds and recovery time of 100 seconds which can be considered as a fairly quick response.

10.
Environ Monit Assess ; 194(11): 827, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36156160

RESUMEN

The current research focuses on the use of different simulation techniques in the future prediction of the crucial aerosol optical properties over the highly polluted Indo-Gangetic Basin in the northern part of India. The time series model was used to make an accurate forecast of aerosol optical depth (AOD) and angstrom exponent (AE), and the statistical variability of both cases was compared in order to evaluate the effectiveness of the model (training and validation). For this, different models were used to simulate the monthly average AOD and AE over Jaipur, Kanpur and Ballia during the period from 2003 to 2018. Further, the study was aimed to construct a comparative model that will be used for time series statistical analysis of MODIS-derived AOD550 and AE412-470. This will provide a more comprehensive information about the levels of AOD and AE that will exist in the future. To test the validity and applicability of the developed models, root-mean-square error (RMSE), mean absolute error (MAE), mean absolute percent error (MAPE), fractional bias (FB), and Pearson coefficient (r) were used to show adequate accuracy in model performance. From the observation, the monthly mean values of AOD and AE were found to be nearly similar at Kanpur and Ballia (0.62 and 1.26) and different at Jaipur (0.25 and 1.14). Jaipur indicates that during the pre-monsoon season, the AOD mean value was found to be highest (0.32 ± 0.15), while Kanpur and Ballia display higher AOD mean values during the winter season (0.72 ± 0.26 and 0.83 ± 0.32, respectively). Among the different methods, the autoregressive integrated moving average (ARIMA) model was found to be the best-suited model for AOD prediction at Ballia based on fitted error (RMSE (0.22), MAE (0.15), MAPE (24.55), FB (0.05)) and Pearson coefficient r (0.83). However, for AE, best prediction was found at Kanpur based on RMSE (0.24), MAE (0.21), MAPE (22.54), FB (-0.09) and Pearson coefficient r (0.82).


Asunto(s)
Contaminantes Atmosféricos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , India , Meteorología
11.
Lett Appl Microbiol ; 75(6): 1596-1606, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36086890

RESUMEN

In this study, a fungal plant growth promoter Penicillium oxalicum T4 isolated from non-rhizosphere soil of Arunachal Pradesh, India, was screened for different plant growth promoting traits in a gnotobiotic study. Though inoculation improved the overall growth of the plants, critical differences were observed in root architecture. Confocal Laser Scanning Microscope, Scanning electron microscope and the stereo microscopic study showed that inoculated wheat plants could develop profuse root hairs as compared to control. Root scanning indicated improvement in cumulative root length, root area, root volume, number of forks, links, crossings, and other parameters. A confocal scanning laser microscope indicated signs of endophytic colonization in wheat roots. Gene expression studies revealed that inoculation of T4 modulated the genes affecting root hair development. Significant differences were marked in the expression levels of TaRSL4, TaEXPB1, TaEXPB23, PIN-FORMED protein, kaurene oxidase, lipoxygenase, ACC synthase, ACC oxidase, 9-cis-epoxycarotenoid dioxygenase, and ABA 8'-hydroxylase genes. These genes contribute to early plant development and ultimately to biomass accumulation and yield. The results suggested that P. oxalicum T4 has potential for growth promotion in wheat and perhaps also in other cereals.


Asunto(s)
Penicillium , Triticum , Reguladores del Crecimiento de las Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/microbiología , Penicillium/genética
13.
Front Genet ; 13: 924287, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35991541

RESUMEN

Pusa 391, a mega desi chickpea variety with medium maturity duration is extensively cultivated in the Central Zone of India. Of late, this variety has become susceptible to Fusarium wilt (FW), which has drastic impact on its yield. Presence of variability in the wilt causing pathogen, Fusarium oxysporum f.sp. ciceri (foc) across geographical locations necessitates the role of pyramiding for FW resistance for different races (foc 1,2,3,4 and 5). Subsequently, the introgression lines developed in Pusa 391 genetic background were subjected to foreground selection using three SSR markers (GA16, TA 27 and TA 96) while 48 SSR markers uniformly distributed on all chromosomes, were used for background selection to observe the recovery of recurrent parent genome (RPG). BC1F1 lines with 75-85% RPG recovery were used to generate BC2F1. The plants that showed more than 90% RPG recovery in BC2F1 were used for generating BC3F1. The plants that showed more than 96% RPG recovery were selected and selfed to generate BC3F3. Multi-location evaluation of advanced introgression lines (BC2F3) in six locations for grain yield (kg/ha), days to fifty percent flowering, days to maturity, 100 seed weight and disease incidence was done. In case of disease incidence, the genotype IL1 (BGM 20211) was highly resistant to FW in Junagarh, Indore, New Delhi, Badnapur and moderately resistant at Sehore and Nandyal. GGE biplot analysis revealed that IL1(BGM20211) was the most stable genotype at Junagadh, Sehore and Nandyal. GGE biplot analysis revealed that IL1(BGM 20211) and IL4(BGM 20212) were the top performers in yield and highly stable across six environments and were nominated for Advanced Varietal Trials (AVT) of AICRP (All India Coordinated Research Project on Chickpea) in 2018-19. BGM20211 and BGM 20212 recorded 29 and 28.5% average yield gain over the recurrent parent Pusa 391, in the AVT-1 and AVT-2 over five environments. Thus, BGM20211 was identified for release and notified as Pusa Manav/Pusa Chickpea 20211 for Madhya Pradesh, Gujarat and Maharashtra, Southern Rajasthan, Bundhelkhand region of Uttar Pradesh states by the Central Sub-Committees on Crop Standards, Notification and Release of Varieties of Agricultural Crops, Ministry of Agriculture and Farmers Welfare, Government of India, for commercial cultivation in India (Gazette notification number S.O.500 (E) dt. 29-1-2021).Such pyramided lines give resilience to multiple races of fusarium wilt with added yield advantage.

14.
Dalton Trans ; 51(33): 12558-12568, 2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-35920308

RESUMEN

The rapid development of efficient and cost-effective catalysts is essential for the oxygen evolution reaction. Herein, nanostructured spinels LiMn2O4, delithiated λ-MnO2, and Li4Mn5O12 have been synthesized at low temperatures and are investigated as electrocatalysts for alkaline water oxidation reactions. Among the nanostructured spinels, LiMn2O4, delithiated λ-MnO2, and Li4Mn5O12, the former spinel which is classical LiMn2O4 with 1/6th of the Mn replaced by Li outperforms for the OER that shows a current density of 5 mA cm-2 at a lowest overpotential of 430 mV and Tafel slope of 74 mV per decade. Electrochemical impedance studies revealed the least value of charge transfer resistance of the Li4Mn5O12 spinel and suggest fast reaction kinetics for the oxygen evolution reaction as compared to other spinels. The XPS and TEM of Li4Mn5O12, recorded after a 12-hour stability test for oxygen evolution activity, confirm that the oxidation state of Mn and the morphology of Li4Mn5O12 remain intact even after the electrocatalytic reaction, however, it undergoes amorphization. The higher activity of Li4Mn5O12 synthesized in the present work is attributed to the low temperature synthesis resulting in the formation of a nanostructured Li rich spinel with a high surface area, along with an increased percentage of ionic bonding and the presence of 3D Li diffusion channels. The role of Li was further supported by XPS studies that revealed a shift in Li 1s binding energy as well as quantitative reduction relative to Mn for Li4Mn5O12 after a long term test.

15.
J Inorg Organomet Polym Mater ; 32(9): 3355-3367, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35599970

RESUMEN

Design of antimicrobial tiles seems necessary to combat against contagious diseases, especially COVID-19. In addition to personal hygiene, this technology facilitates public hygiene as antimicrobial tiles can be installed at hospitals, schools, banks, offices, lobbies, railway stations, etc. This review is primarily focused on preparing antimicrobial tiles using an antimicrobial layer or coatings that fight against germs. The salient features and working mechanisms of antimicrobial tiles are highlighted. This challenge is a component of the exploratory nature of nanoarchitectonics, that also extends farther than the realm of nanotechnology. This nanoarchitectonics has been successful at the laboratory scale as antimicrobial metal nanoparticles are mainly used as additives in preparing tiles. A detailed description of various materials for developing unique antimicrobial tiles is reported here. Pure metal (Ag, Zn) nanoparticles and a mixture of nanoparticles with other inorganic materials (SiO2,, TiO2, anatase, nepheline) have been predominantly used to combat microbes. The developed antimicrobial tiles have shown excellent activity against a wide range of Gram-positive and Gram-negative bacteria. The last section discussed a hypothetical overview of utilizing the antimicrobial tiles against SARS-CoV-2. Overall, this review gives descriptive knowledge about the importance of antimicrobial tiles to create a clean and sustainable environment.

16.
ACS Appl Mater Interfaces ; 14(17): 20220-20229, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35451828

RESUMEN

Mechanical components are exposed to a rigorous environment in a number of applications including engineering, aerospace, and automobiles. Thus, their service lifetime and reliability are always on the verge of risk. Protective coatings with high hardness are required to enhance their service lifetime and minimize the replacement cost and waste burden. Hydrogenated amorphous carbon including nitrogen-incorporated films, that are commonly deposited by plasma-enhanced chemical vapor deposition, are widely used for commercial protective coating applications. However, their mechanical hardness still falls into the moderate hard regime. This needs to be substantially enhanced for advanced applications. Here, we report the synthesis of very hard nanostructured hydrogenated carbon-nitrogen hybrid (n-C:H:N) films. The optimized n-C:H:N film displays a hardness of about 36 GPa, elastic modulus of 360 GPa, and reasonably good elastic recovery (ER) of 62.7%. The mechanical properties of n-C:H:N films are further tailored when nitrogen pressure is tuned during the growth. The realized remarkably improved mechanical properties are correlated with the films' structural properties and experimental growth conditions. We also conducted density functional theory calculations that show the trend for the elastic modulus of the amorphous carbon films with varying nitrogen concentrations matches well with experimentally measured values. Finally, we probed load-dependent mechanical properties of n-C:H:N films and found an anomalous behavior; some of the mechanical parameters, for instance, ER, reveal an irregular trend with indentation load, which we explain in the framework of the film-substrate composite concept. Overall, this work uncovers many unknown and exciting mechanical phenomena that could pave the way for new technological developments.

18.
J Endovasc Ther ; 29(5): 678-691, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34955053

RESUMEN

BACKGROUND: Carotid plaque morphology plays an important role in determining outcome of carotid artery stenting (CAS). Intravascular ultrasound (IVUS) and its extension VH (Virtual Histology)-IVUS evaluate plaque characteristics in real time and guide decision making during stenting. To date, there is no consensus about indications of IVUS and its validated methods. This systematic review and meta-analysis aims to evaluate the clinical utility of IVUS in carotid artery interventions (CAS) and develop a future consensus for research and practice parameters. METHODS: A systematic review and meta-analysis was performed of the English literature articles published till February 2021. Studies reporting on IVUS parameters and findings and also its performance compared with other imaging modalities were included in review. Pooled prevalence with 95% confidence intervals (CI) was calculated. The statistical analysis was conducted in R version 3.6.2. RESULTS: A total of 2015 patients from 29 studies were included. Proportional meta-analysis was performed on 1566 patients from 11 studies. In 9 studies, stroke/transient ischemic attack (TIA) had a pooled prevalence of 4% (95% CI 3%-5%) while asymptomatic stroke had a pooled prevalence of 46% (95% CI 31%-62%) in 4 studies following IVUS. Two studies reported that IVUS detected more plaque protrusion compared with angiography (n=33/396 vs 11/396). IVUS led to stent type or size change in 8 of 48 cases which were missed on angiography in 3 other studies. Concordance between VH-IVUS and true histology was good at 80% to 85% reported in 2 studies. CONCLUSIONS: This systematic review and meta-analysis showed, though IVUS fared better to computed tomography (CT)/magnetic resonance (MR) angiography for better stent selection during CAS, with low to moderate risk of bias in the studies included. However, large scale, preferably randomized controlled studies are needed to predict its role in determining clinical outcome.


Asunto(s)
Estenosis Carotídea , Placa Aterosclerótica , Accidente Cerebrovascular , Arterias Carótidas/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/terapia , Humanos , Angiografía por Resonancia Magnética , Placa Aterosclerótica/patología , Valor Predictivo de las Pruebas , Stents , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Resultado del Tratamiento , Ultrasonografía Intervencional
19.
Indian J Pathol Microbiol ; 64(4): 633-637, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34673578

RESUMEN

BACKGROUND: Tanycytic ependymoma (TE) (WHO grade II) is a rare and morphologically distinct variant of ependymoma with only 77 cases reported worldwide so far. Variable clinical and radio-pathological features lead to misdiagnosis as WHO grade 1 tumors. On imaging, differentials of either schwannoma, meningioma, low-grade glial (like angiocentric glioma), or myxopapillary ependymoma are considered. In this study, we aim to discuss clinical, radiological, and pathological features of TE from our archives. METHOD: We report clinicopathological aspects of six cases of TE from archives of tertiary care center between 2016 and 2018. Detailed histological assessment in terms of adequate tissue sampling and immunohistochemistry was done for each case. RESULT: The patient's age ranged between 10 and 53 years with a slight male predilection. Intraspinal location was seen in two cases (intramedullary and extramedullary), three cases were cervicomedullary (intramedullary), and one was intracranial. One case was associated with neurofibromatosis type 2. Four cases mimicked as either schwannoma or low-grade glial tumor on squash smears. On imaging, ependymoma as differential was kept in only two cases and misclassified remaining either as low-grade glial or schwannoma. DISCUSSION: In initial published reports, the spine is the most common site (50.4%) followed by intracranial (36.4%) and cervicomedullary (3.9%). They have also highlighted the challenges in diagnosing them intraoperatively and radiologically. Treatment is similar to conventional ependymoma if diagnosed accurately. A multidisciplinary approach with the integration of neurosurgeon, neuroradiologist, and neuropathologist is required for accurate diagnosis and better treatment of patients.


Asunto(s)
Encefalopatías/fisiopatología , Ependimoma/diagnóstico , Ependimoma/fisiopatología , Ependimoma/terapia , Inmunohistoquímica/métodos , Neoplasias Glandulares y Epiteliales/fisiopatología , Enfermedades de la Médula Espinal/fisiopatología , Adolescente , Adulto , Encefalopatías/diagnóstico por imagen , Niño , Ependimoma/diagnóstico por imagen , Femenino , Técnicas Histológicas , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Glandulares y Epiteliales/diagnóstico por imagen , Enfermedades de la Médula Espinal/diagnóstico por imagen , Adulto Joven
20.
Nano Lett ; 21(21): 8960-8969, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34714644

RESUMEN

Lubricity, a phenomenon which enables the ease of motion of objects, and wear resistance, which minimizes material damage or degradation, are important fundamental characteristics for sustainable technology developments. Ultrathin coatings that promote lubricity and wear resistance are of huge importance for a number of applications, including magnetic storage and micro-/nanoelectromechanical systems. Conventional ultrathin coatings have, however, reached their limit. Graphene-based materials that have shown promise to reduce friction and wear have many intrinsic limitations such as high temperature and substrate-specific growth. To address these concerns, a great deal of research is currently ongoing to optimize graphene-based materials. Here we discover that angstrom-thick carbon (8 Å) significantly reduces interfacial friction and wear. This lubricant shows ultrahigh optical transparency and can be directly deposited on a wide range of surfaces at room temperature. Experiments combined with molecular dynamics simulations reveal that the lubricating efficacy of 8 Å carbon is further improved via interfacial nitrogen.

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