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1.
J Funct Biomater ; 15(4)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38667539

RESUMO

Three-dimensional (3D) bioprinting is a fast prototyping fabrication approach that allows the development of new implants for tissue restoration. Although various materials have been utilized for this process, they lack mechanical, electrical, chemical, and biological properties. To overcome those limitations, graphene-based materials demonstrate unique mechanical and electrical properties, morphology, and impermeability, making them excellent candidates for 3D bioprinting. This review summarizes the latest developments in graphene-based materials in 3D printing and their application in tissue engineering and regenerative medicine. Over the years, different 3D printing approaches have utilized graphene-based materials, such as graphene, graphene oxide (GO), reduced GO (rGO), and functional GO (fGO). This process involves controlling multiple factors, such as graphene dispersion, viscosity, and post-curing, which impact the properties of the 3D-printed graphene-based constructs. To this end, those materials combined with 3D printing approaches have demonstrated prominent regeneration potential for bone, neural, cardiac, and skin tissues. Overall, graphene in 3D bioprinting may pave the way for new regenerative strategies with translational implications in orthopedics, neurology, and cardiovascular areas.

2.
Cureus ; 16(3): e55642, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38586766

RESUMO

This case report discusses the intricate diagnostic and therapeutic challenges faced by a 23-year-old Indian male who presented with altered consciousness, a holo-cranial headache, right-sided hemiparesis, and subsequent neurological symptoms. The patient's dietary habits, leading to vitamin B12 and folic acid deficiencies resulting in hyperhomocysteinemia, along with binge alcohol drinking leading to dehydration, were identified as the main causes of cerebral venous sinus thrombosis (CVST) in this case. The case was complicated by an additional cerebral hemorrhage. The patient received a comprehensive treatment regimen involving antiepileptic medications, intravenous fluids, and anticoagulation therapy. A decline in the Glasgow Coma Scale score prompted further interventions. Collaborative decision-making, involving neurologists, neurosurgeons, and the patient's relatives, steered the treatment course, ultimately favoring continued medical management over decompression surgery. Notably, the patient exhibited remarkable progress in mobility, achieving the ability to walk with support by the end. This case report contributes valuable insights to the understanding of CVST, emphasizing the significance of nutritional considerations, especially in vegetarians, and underscoring the importance of thorough diagnostic evaluations in complex clinical scenarios.

3.
Nanoscale ; 16(15): 7467-7479, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38511345

RESUMO

A high-temperature pyrolysis-controlled coordination reconstruction resulted in a single-Ni-atom structure with a Ni-Nx-C structural unit (x = N atom coordinated to Ni). Pyrolysis of Ni-phen@ZIF-8-RF at 700 °C resulted in NiNP-NC-700 with predominantly Ni nanoparticles. Upon elevating the pyrolysis temperature from 700 to 900 °C, a coordination reconstruction offers Ni-Nx atomic sites in NiSA-NC-900. A combined investigation with X-ray absorption spectroscopy, X-ray photoelectron spectroscopy, and soft X-ray L3-edge spectroscopy suggests the stabilization of low-valent Niδ+ (0 < δ < 2) in the Ni-N-C structural units. The oxygen evolution reaction (OER) is a key process during water splitting in fuel cells. However, OER is a thermodynamically uphill reaction with multi-step proton-coupled electron transfer and sluggish kinetics, due to which there is a need for a catalyst that can lower the OER overpotentials. The adsorption energy of a multi-step reaction on a single metal atom with coordination unsaturation tunes the adsorption of each oxygenated intermediate. The promising OER activity of the NiSA-NC-900/NF anode on nickel foam was followed by the overall water splitting (OWS) using using NiSA-NC-900/NF as anode and Pt coil as the cathodic counterpart, wherein a cell potential of 1.75 V at 10 mA cm-2 was achieved. The cell potential recorded with Pt(-)/(+)NiSA-NC-900/NF was much lower than that obtained for other cells, i.e., Pt(-)/NF and NF(-)/(+)NF, which enhances the potentials of low-valent NiSAs for insightful understanding of the OER. At a constant applied potential of 1.61 V (vs. RHE) for 12 h, an small increase in current for initial 0.6 h followed by a constant current depicts the fair stability of catalyst for 12 h. Our results offer an insightful angle into the OER with a coordinatively reconstructed single-Ni-atom structure at lower valency (<+2).

4.
Artigo em Inglês | MEDLINE | ID: mdl-38458653

RESUMO

OBJECTIVES: To evaluate the value of Spinal Instability Neoplastic Score (SINS) in patients with spine metastasis who subsequently developed or did not develop metastatic spinal cord compression (MSCC). METHODS: In this single institutional retrospective descriptive observational study, of 589 patients with MSCC who were referred for radiotherapy, 34 patients (with 41 compression sites) met the inclusion criteria: availability of diagnostic MRI spine pre-development of MSCC (MRI-1) and at the time of MSCC development (MRI-2) (CordGroup).For comparison, NoCordGroup consisted of 152 patients (160 sites) treated with radiotherapy to spinal metastases. SINS was compared between the two groups. RESULTS: In CordGroup, the median interval between MRI-1 and MRI-2 was 11 weeks. The median SINS was 8 (range: 4-14) and 9 (range: 7-14) on MRI-1 and MRI-2, respectively. In NoCordGroup, the median SINS was 6 (range: 4-10). CONCLUSIONS: Our study showed a trend in difference in SINS value between the two groups. This difference should be a subject of future prospective research in this patient population with poor survival.

5.
Biomolecules ; 14(2)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38397377

RESUMO

A monolayer of endothelial cells (ECs) lines the lumen of blood vessels and, as such, provides a semi-selective barrier between the blood and the interstitial space. Compromise of the lung EC barrier due to inflammatory or toxic events may result in pulmonary edema, which is a cardinal feature of acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome (ARDS). The EC functions are controlled, at least in part, via epigenetic mechanisms mediated by histone deacetylases (HDACs). Zinc-dependent HDACs represent the largest group of HDACs and are activated by Zn2+. Members of this HDAC group are involved in epigenetic regulation primarily by modifying the structure of chromatin upon removal of acetyl groups from histones. In addition, they can deacetylate many non-histone histone proteins, including those located in extranuclear compartments. Recently, the therapeutic potential of inhibiting zinc-dependent HDACs for EC barrier preservation has gained momentum. However, the role of specific HDAC subtypes in EC barrier regulation remains largely unknown. This review aims to provide an update on the role of zinc-dependent HDACs in endothelial dysfunction and its related diseases. We will broadly focus on biological contributions, signaling pathways and transcriptional roles of HDACs in endothelial pathobiology associated mainly with lung diseases, and we will discuss the potential of their inhibitors for lung injury prevention.


Assuntos
Células Endoteliais , Histona Desacetilases , Histona Desacetilases/metabolismo , Células Endoteliais/metabolismo , Epigênese Genética , Zinco/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Pulmão/metabolismo , Histonas/metabolismo
6.
Med Res Rev ; 44(1): 365-405, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37589449

RESUMO

Diabetes and its complications, Alzheimer's disease (AD), and Parkinson's disease (PD) are increasing gradually, reflecting a global threat vis-à-vis expressing the essentiality of a substantial paradigm shift in research and remedial actions. Protein glycation is influenced by several factors, like time, temperature, pH, metal ions, and the half-life of the protein. Surprisingly, most proteins associated with metabolic and neurodegenerative disorders are generally long-lived and hence susceptible to glycation. Remarkably, proteins linked with diabetes, AD, and PD share this characteristic. This modulates protein's structure, aggregation tendency, and toxicity, highlighting renovated attention. Gut microbes and microbial metabolites marked their importance in human health and diseases. Though many scientific shreds of evidence are proposed for possible change and dysbiosis in gut flora in these diseases, very little is known about the mechanisms. Screening and unfolding their functionality in metabolic and neurodegenerative disorders is essential in hunting the gut treasure. Therefore, it is imperative to evaluate the role of glycation as a common link in diabetes and neurodegenerative diseases, which helps to clarify if modulation of nonenzymatic glycation may act as a beneficial therapeutic strategy and gut microbes/metabolites may answer some of the crucial questions. This review briefly emphasizes the common functional attributes of glycation and gut microbes, the possible linkages, and discusses current treatment options and therapeutic challenges.


Assuntos
Doença de Alzheimer , Diabetes Mellitus , Microbioma Gastrointestinal , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doença de Alzheimer/tratamento farmacológico , Reação de Maillard
7.
Sci Transl Med ; 15(726): eadh9902, 2023 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-38091406

RESUMO

New drugs for visceral leishmaniasis that are safe, low cost, and adapted to the field are urgently required. Despite concerted efforts over the last several years, the number of new chemical entities that are suitable for clinical development for the treatment of Leishmania remains low. Here, we describe the discovery and preclinical development of DNDI-6174, an inhibitor of Leishmania cytochrome bc1 complex activity that originated from a phenotypically identified pyrrolopyrimidine series. This compound fulfills all target candidate profile criteria required for progression into preclinical development. In addition to good metabolic stability and pharmacokinetic properties, DNDI-6174 demonstrates potent in vitro activity against a variety of Leishmania species and can reduce parasite burden in animal models of infection, with the potential to approach sterile cure. No major flags were identified in preliminary safety studies, including an exploratory 14-day toxicology study in the rat. DNDI-6174 is a cytochrome bc1 complex inhibitor with acceptable development properties to enter preclinical development for visceral leishmaniasis.


Assuntos
Leishmaniose Visceral , Leishmaniose , Ratos , Animais , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Modelos Animais de Doenças
8.
ACS Appl Bio Mater ; 6(10): 4060-4080, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37787456

RESUMO

Self-powered biofuel cells (BFCs) have evolved for highly sensitive detection of biomarkers such as noncodon micro ribonucleic acids (miRNAs) in the presence of interfering substrates. Self-charging supercapacitive BFCs for in vivo and in vitro cellular microenvironments represent the most prevalent sensing mechanism for diagnosis. Therefore, self-powered biosensing (SPB) with a capacitor and contact separation with a triboelectric nanogenerator (TENG) offers electrochemical and colorimetric dual-mode detection via improved electrical signal intensity. In this review, we discuss three major components: stretchable self-powered BFC design, miRNA sensing, and impedance spectroscopy. A specific focus is given to 1) assembling of sensors for biomarkers, 2) electrical output signal intensification, and 3) role of supercapacitors and nanogenerators in SPBs. We outline the key features of stretchable SPBs and the sequence of miRNA sensing by SPBs. We have emphasized the need of a supercapacitor and nanogenerator for SPBs in the context of advanced assembly of the sensing unit. Finally, we outline the role of impedance spectroscopy in the detection and estimation of biomarkers. We highlight key challenges in SPBs for biomarker sensing, which needs improved sensing accuracy, integration strategies of electrochemical biosensing for in vitro and in vivo microenvironments, and the impact of miRNA sensing on cancer diagnostics. This article attempts a specific focus on the accuracy and limitations of sensing unit for miRNA biomarkers and associated tool for boosting electrical signal intensity for a potential big step further.


Assuntos
Fontes de Energia Bioelétrica , MicroRNAs , Eletricidade , Biomarcadores , Microambiente Celular
9.
J Pharm Bioallied Sci ; 15(Suppl 2): S1093-S1096, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37693965

RESUMO

Background: HNSCC (head and neck squamous cell carcinoma) is a serious global health problem, with estimated more than 550,000 new cases and 300,000 deaths annually. More than 90% of these malignancies are oral squamous cell carcinoma (OSCC). Materials and Methods: Patients selected were asked to fill the detailed structured case history proforma and thorough clinical examination, structured, pre-designed, pre-evaluated (UW-QOL) UW Questionnaire version 4 on quality of life (QOL) of oral squamous cell carcinoma patients containing thirteen subjective questionnaires and three global questionnaires. All the patients of OSCC after one month (1 month) of radiation and chemotherapy were assessed for quality of life by questionnaire. Result: Post-treatment QOL assessment of OSCC patients reveals a number of problems such as chewing, swallowing, saliva, lack of activity, and mood disturbances. Preoperative clinical features including tumor site, tumor stage, and extent of mouth opening have a significant impact on post-treatment problems in different ways. Conclusion: The need to balance clinician's need and use of health-related quality of life (HRQOL) data against patient's burden should be considered in the selection process.

10.
J Pharm Bioallied Sci ; 15(Suppl 2): S1132-S1135, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37694000

RESUMO

Introduction: The pulp is the most negatively impacted tissue during decalcification since it comprises the soft tissue components. The most effective decalcifying agent would be safest for cells and tissues while yet removing all traces of calcium. It has to get the job done quickly and have good staining properties. Aim and Objective: The goal of this research was to identify the most effective decalcifying agent for diagnostic purposes via a qualitative investigation of tissue preservation and a comparison of the efficiency of several decalcifying agents on human permanent teeth, covering both hard and soft tissue components. Materials and Methods: Fifty premolars from people aged 14 to 30 who needed them pulled for orthodontics were included in the research. Participants in the research were divided into five groups of ten. Group A, Group B, Group C, Group D, and Group E make up the total of five groups. In this investigation, we compared the efficiency of five decalcifying chemicals and analyzed their staining patterns and effects on tooth tissue. Fifty premolar teeth from participants aged 14-30 years old were removed for orthodontic therapy. For the research, they were split up into five groups of ten. Group A contains 5% ethylenediaminetetraacetic acid (EDTA), Group B contains 10% formic acid, Group C contains 5% Trichoraticectic acid, Group D contains 5% nitric acid, and Group E contains 5% formalin-nitric acid. Result: Regardless of the specifics of the chosen decalcification solution, all procedures benefit from the inclusion of external stimuli. None of the variables were used in the current investigation; it was conducted only to compare various decalcifying chemicals. Conclusion: When time is not a concern, neutral EDTA may be recommended for preservation and presentation because of its ability to maintain soft-tissue integrity and provide high-quality staining. The formalin-nitric acid solution was one agent that appeared to strike a good compromise between speed and tissue preservation.

11.
ACS Infect Dis ; 9(10): 1964-1980, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37695781

RESUMO

We discovered dibenzannulated medium-ring keto lactams (11,12-dihydro-5H-dibenzo[b,g]azonine-6,13-diones) as a new antimalarial chemotype. Most of these had chromatographic LogD7.4 values ranging from <0 to 3 and good kinetic solubilities (12.5 to >100 µg/mL at pH 6.5). The more polar compounds in the series (LogD7.4 values of <2) had the best metabolic stability (CLint values of <50 µL/min/mg protein in human liver microsomes). Most of the compounds had relatively low cytotoxicity, with IC50 values >30 µM, and there was no correlation between antiplasmodial activity and cytotoxicity. The four most potent compounds had Plasmodium falciparum IC50 values of 4.2 to 9.4 nM and in vitro selectivity indices of 670 to >12,000. They were more than 4 orders-of-magnitude less potent against three other protozoal pathogens (Trypanosoma brucei rhodesiense, Trypanosoma cruzi, and Leishmania donovani) but did have relatively high potency against Toxoplasma gondii, with IC50 values ranging from 80 to 200 nM. These keto lactams are converted into their poorly soluble 4(1H)-quinolone transannular condensation products in vitro in culture medium and in vivo in mouse blood. The similar antiplasmodial potencies of three keto lactam-quinolone pairs suggest that the quinolones likely contribute to the antimalarial activity of the lactams.


Assuntos
Antimaláricos , Quinolonas , Trypanosoma cruzi , Camundongos , Animais , Humanos , Antimaláricos/farmacologia , Antimaláricos/química , Lactamas , Trypanosoma brucei rhodesiense
12.
Indian J Otolaryngol Head Neck Surg ; 75(3): 1511-1516, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37636778

RESUMO

Aims: The present study examines the role of demographic and pathological features of primary tumours in predicting neck metastasis in early oral cavity cancers, which has been a matter of debate. Methods: A single-centre, retrospective, institution review was conducted of all the patients presented to our centre from January 2014 to December 2021. Patient characteristics were compared between the two lymph node groups (lymph node positive and lymph node negative) and significant prognostic factors were determined. Results: A total of 462 oral squamous cell carcinoma (OSCC) patients were included, 407 male and 55 female. Tobacco chewing (59.2%) was a major habit with buccal mucosa (49.5%) and tongue (44.8%) as primary sites. The majority of the patient's histology was of SCC (96.8%) with grade II (moderately differentiated, 74.5%). Univariate logistic regression analysis to predict lymph node metastasis showed pT size (< 0.001), LVI (< 0.001), and PNI (< 0.001) as significant tumor characteristics. On multivariate, pT size (OR-1.58, P - 0.0001) and LVI (OR-19.70, P - 0.0001) were reported to be statistically significant to predict lymph node metastasis. Conclusion: Reporting and studying the clinico-pathological features of primary tumors can give vital information in predicting the neck node metastasis in OSCC patients.

13.
J Oral Pathol Med ; 52(9): 849-859, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37573872

RESUMO

BACKGROUND: Translationally controlled tumour protein (TCTP) is a multifunctional protein elevated in multiple cancers. However, studies on its role in oral carcinogenesis and prognosis are rare. We recently reported the role of its interacting partner, MCL1, in oral cancer progression and outcome. Hence, the present study aimed to assess TCTP expression in oral tumorigenesis and its association with patient outcomes alone and in combination with MCL1. METHODS: TCTP expression was assessed by immunohistochemistry and immunoblotting in oral tissues and cells, respectively. Cell viability post siRNA/dihydroartemisinin treatment was analysed by tetrazolium salt assay. Cell survival, invasion and tumorigenic potential post TCTP knockdown were assessed by clonogenic, Matrigel and soft-agar assays, respectively. The association of TCTP with patient outcome was analysed by Kaplan-Meier and Cox regression. RESULTS: TCTP was significantly overexpressed in oral premalignant lesions (p < 0.0001), oral tumours (p < 0.0001) and oral dysplastic and cancer cells versus normal oral mucosa and also in recurrent (p < 0.05) versus non-recurrent oral tumours. Further, elevated TCTP was significantly (p < 0.05) associated with poor recurrence free survival (RFS) and poor overall survival (OS; hazard ratio = 2.29; p < 0.05). Intriguingly, the high co-expression of TCTP and MCL1 further reduced the RFS (p < 0.05) and OS (p < 0.05; hazard-ratio = 3.49; p < 0.05). Additionally, TCTP knockdown decreased survival (p < 0.05), invasion (p < 0.01) and in vitro tumorigenic potential (p < 0.0001). Dihydroartemisinin treatment reduced TCTP levels and viability of oral cancer cells. CONCLUSION: Our studies demonstrate an oncogenic role of TCTP in oral cancer progression and poor outcome. Thus, TCTP may be a potential prognostic marker and therapeutic target in oral cancers.


Assuntos
Artemisininas , Neoplasias Bucais , Humanos , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias Bucais/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteína Tumoral 1 Controlada por Tradução
14.
Biomedicines ; 11(6)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37371733

RESUMO

Vascular barrier dysfunction is characterized by increased permeability and inflammation of endothelial cells (ECs), which are prominent features of acute lung injury (ALI), acute respiratory distress syndrome (ARDS), and sepsis, and a major complication of the SARS-CoV-2 infection and COVID-19. Functional impairment of the EC barrier and accompanying inflammation arises due to microbial toxins and from white blood cells of the lung as part of a defensive action against pathogens, ischemia-reperfusion or blood product transfusions, and aspiration syndromes-based injury. A loss of barrier function results in the excessive movement of fluid and macromolecules from the vasculature into the interstitium and alveolae resulting in pulmonary edema and collapse of the architecture and function of the lungs, and eventually culminates in respiratory failure. Therefore, EC barrier integrity, which is heavily dependent on cytoskeletal elements (mainly actin filaments, microtubules (MTs), cell-matrix focal adhesions, and intercellular junctions) to maintain cellular contacts, is a critical requirement for the preservation of lung function. EC cytoskeletal remodeling is regulated, at least in part, by Ser/Thr phosphorylation/dephosphorylation of key cytoskeletal proteins. While a large body of literature describes the role of phosphorylation of cytoskeletal proteins on Ser/Thr residues in the context of EC barrier regulation, the role of Ser/Thr dephosphorylation catalyzed by Ser/Thr protein phosphatases (PPases) in EC barrier regulation is less documented. Ser/Thr PPases have been proposed to act as a counter-regulatory mechanism that preserves the EC barrier and opposes EC contraction. Despite the importance of PPases, our knowledge of the catalytic and regulatory subunits involved, as well as their cellular targets, is limited and under-appreciated. Therefore, the goal of this review is to discuss the role of Ser/Thr PPases in the regulation of lung EC cytoskeleton and permeability with special emphasis on the role of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A) as major mammalian Ser/Thr PPases. Importantly, we integrate the role of PPases with the structural dynamics of the cytoskeleton and signaling cascades that regulate endothelial cell permeability and inflammation.

15.
Front Immunol ; 14: 1181991, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342350

RESUMO

For the efficacy of COVID-19 vaccines, emergence of variants accumulating immune-escape mutations remains a major concern. We analyzed the anti-variant (n = 10) neutralization activity of sera from COVID-19 patients infected with Wuhan (B.1), Kappa, and Delta variants and COVISHIELD vaccine recipients with (prepositives) or without (prenegatives) prior antibody positivity using V- PLEX ACE2 Neutralization Kit from MSD. MSD and PRNT50 correlated well (r = 0.76-0.83, p < 0.0001). Despite the least antibody positivity in Kappa patients, anti-variant neutralizing antibody (Nab) levels in the responders were comparable with Delta patients. Vaccinees sampled at 1 month (PD2-1) and 6 months (PD2-6) post-second dose showed the highest seropositivity and Nab levels against the Wuhan strain. At PD2-1, the responder rate was variant-dependent and 100% respectively in prenegatives and prepositives. Nab levels against B.1.135.1, B.1.620, B.1.1.7+E484K (both groups), AY.2 (prenegatives), and B.1.618 (prepositives) were lower than that of Wuhan. At PD2-6, positivity decreased to 15.6%-68.8% in the prenegatives; 3.5%-10.7% of prepositives turned negative for the same four variants. As against the decline in Nab levels in 9/10 variants (prenegatives), a further reduction was seen against the same four variants in the prepositives. These variants possess immune-evasion-associated mutations in the RBD/S region. In conclusion, our data show that the Nab response of patients to multiple variants depends on the infecting variant. We confirm superiority of hybrid immunity in neutralizing multiple variants. Depending on the infecting variant pre- or postvaccination, immune response to different vaccines in different populations will vary and impact protection against emerging variants. The MSD platform provides an excellent alternative to live virus/pseudovirus neutralization tests.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , ChAdOx1 nCoV-19 , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Índia , Anticorpos Neutralizantes , Imunização
16.
Chemistry ; 29(38): e202301117, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37147877

RESUMO

Environmental protection associated with renewable energy is among the most critical challenges for translational ion-capture based on capacitive storage of ions in electrical double layers at the interface of electrode and electrolyte. Electric double-layer capacitance with charge induction and faradaic pseudo-capacitance with charge transfer classifies the capacitance of the electrochemical interface. The electrochemical interface in most energy technologies involves porous and pseudocapacitive redox materials that offer varying degrees of electrolyte confinement. In this review, we discuss the factors affecting water desalination, such as the effect of nanopores for ion capture, the ion sieving effect, the effect of hydration energy, and hydration radius in the carbon sub-nanometer pore. Moreover, the surface phenomena of electrodes, including carbon corrosion, and the potential of zero charge to control the oxidation of carbon electrodes are explained along with protection mechanisms. The various capacitive deionization (CDI) operations and the corresponding electrochemical cell technologies are briefly introduced, including the significance of double-layer charging materials with faradaic intercalation, which suffer less from co-ion expulsion. Finally, we revisit the effects of various nanoarchitectures and the construction of capacitive deionization electrodes for clean water technology.


Assuntos
Carbono , Purificação da Água , Carbono/química , Capacitância Elétrica , Íons , Eletrodos , Água
17.
Small ; 19(29): e2301675, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37170689

RESUMO

Precise configurations of isolated metal atoms in nitrogen-doped carbon materials with 2D single or multilayers and 3D nanoarchitectures are gaining attention owing to their good stability and activity at high current densities. Atomic metal-Nx moieties, which utilize maximum atoms to attain high intrinsic activity and novel electronic architecture of support materials, facilitate strong interaction between the central metal atom and support matrix. However, resource consumption is considerably high due to the inferior atomic utilization of active sites. Therefore, energy-efficient electrochemical processes are needed to develop advanced isolated single-atom architecture, which would provide high atom-utilization and good durability. Herein, the concepts of atomically dispersed metal sites in single-atom and alloy architectures and their electronic features associated with structural evolution are discussed. Opportunities and challenges associated with the use of isolated single-atoms in 2D materials are discussed based on their unique electronic defects, low-valence central metals, mechanical flexibility, and maximum access to metal sites. This insightful revisit into the engineering of single-atom and alloy architectures would provide a profound understanding of electronic modulations and regulation of geometric characteristics, and unravels potential directions for electrochemical energy conversion, charge storage, and sensing processes.

18.
ACS Appl Mater Interfaces ; 15(20): 24329-24345, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37186804

RESUMO

Catalysts consisting of metal-metal hydroxide/oxide interfaces are highly in demand for advanced catalytic applications as their multicomponent active sites will enable different reactions to occur in close proximity through synergistic cooperation when a single component fails to promote it. To address this, herein we disclosed a simple, scalable, and affordable method for synthesizing catalysts consisting of nanoscale nickel-nickel oxide-zinc oxide (Ni-NiO-ZnO) heterojunctions by a combination of complexation and pyrolytic reduction. The modulation of active sites of catalysts was achieved by varying the reaction conditions of pyrolysis, controlling the growth, and inhibiting the interlayer interaction and Ostwald ripening through the efficient use of coordinated acetate and amide moieties of Zn-Ni materials (ZN-O), produced by the reaction between hydrazine hydrate and Zn-Ni-acetate complexes. We found that the coordinated organic moieties are crucial for forming heterojunctions and their superior catalytic activity. We analyzed two antagonistic reactions to evaluate the performance of the catalysts and found that while the heterostructure of Ni-NiO-ZnO and their cooperative synergy were crucial for managing the effectiveness and selectivity of the catalyst for dehydrogenation of aryl alkanes/alkenes, they failed to enhance the hydrogenation of nitro arenes. The hydrogenation reaction was influenced by the shape, surface properties, and interaction of the hydroxide and oxide of both zinc and nickel, particularly accessible Ni(0). The catalysts showed functional group tolerance, multiple reusabilities, broad substrate applicability, and good activity for both reactions.

19.
Indian Pediatr ; 60(7): 553-556, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37078483

RESUMO

OBJECTIVE: To assess QT interval abnormalities among children with breath-holding spells. METHODS: This case control study included 204 children (104 cases of breath-holding spells and 100 healthy children) younger than 3 years. Breath-holding spells were evaluated for age of onset, type (pallid/cyanotic), triggering factors, frequency and presence of family history. Twelve- lead surface electrocardiogram (ECG) was analyzed for QT interval (QT), corrected QT interval (QTc), QT dispersion (QTD) and QTc dispersion (QTcD) in milliseconds. RESULTS: The mean (SD) QT, QTc, QTD and QTcD interval in milliseconds were 320 (0.05), 420 (0.07), 61.15 (16.20), 102.3 (17.24), respectively for breath-holding spells as compared to control group [300 (0.02), 370 (0.03), 38.6(14.28), 78.6 (14.28), respectively] (P<0.001). Similarly, pallid breath-holding spells had prolonged mean (SD) QT, QTc, QTD and QTcD interval in milliseconds [380 (0.04), 520 (0.08), 78.88 (10.78), 123.33 (10.28), respectively] as compared to cyanotic spells [310 (0.04), 400 (0.04), 57.44 (14.64), 97.90 (15.03), respectively] (P<0.001). The mean QTc interval was 590 (0.03) and 400 (0.04) milliseconds in prolonged and non-prolonged QTc group, respectively (P<0.001). CONCLUSION: Abnormal QT, QTc, QTD and QTcD were observed among children with breath-holding spells. ECG should be strongly considered, especially in pallid, frequent spells occurring at younger age and having positive family history, to identify long QT syndrome.


Assuntos
Suspensão da Respiração , Eletrocardiografia , Síndrome do QT Longo , Síndrome do QT Longo/diagnóstico , Estudos de Casos e Controles , Humanos , Criança , Cianose
20.
J Cataract Refract Surg ; 49(1): 76-83, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36026712

RESUMO

PURPOSE: To assess phase retardation and corneal sublayer thickness repeatability using ultrahigh-resolution polarization-sensitive optical coherence tomography (PS-OCT). SETTING: Narayana Nethralaya Eye Hospital, Bangalore. DESIGN: Observational. METHODS: In this study, all eyes were imaged using a custom-built ultrahigh-resolution PS-OCT and high-resolution hybrid OCT (MS-39). The repeatability of phase retardation en face maps and corneal sublayer thickness profiles was evaluated. The reflectivity and phase retardation were calculated from the 2 orthogonal polarization channels to generate en face maps of phase retardation and corneal sublayer thicknesses. 3 consecutive measurements of all participants were acquired for each eye. For each measurement, the participant was asked to sit back and was realigned again. The repeatability was assessed using the intraclass correlation coefficient (ICC). RESULTS: The study included 20 healthy eyes of 20 participants. The phase retardation en face maps showed preferential arrangement of collagen fibrils with least retardation in the apex and maximum retardation in the periphery. The phase retardation showed excellent repeatability (ICC >0.95) in all zones. The Bowman layer and stromal layer thicknesses were measured with excellent repeatability (ICC >0.93 and >0.99, respectively). Significant differences ( P < .05) in stromal layer thickness were observed between MS-39 and PS-OCT. The repeatability of epithelial thickness measurements was better with PS-OCT than MS-39. CONCLUSIONS: The combinational assessment of corneal birefringence and sublayer thicknesses shows the advanced potential of ultrahigh-resolution PS-OCT in routine clinical practice over current OCT devices.


Assuntos
Córnea , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Reprodutibilidade dos Testes , Índia , Refração Ocular , Paquimetria Corneana
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