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The study presents a series of examples of magnetic nanoparticle systems designed for the diagnosis of viral diseases. In this interdisciplinary work, we describe one of the most comprehensive synthetic approaches for the preparation and functionalization of smart nanoparticle systems for rapid and effective RT-PCR diagnostics and isolation of viral RNA. Twelve different organic ligands and inorganic porous silica were used for surface functionalization of the Fe3O4 magnetic core to increase the number of active centres for efficient RNA binding from human swab samples. Different nanoparticle systems with common beads were characterized by HRTEM, SEM, FT-IR, XRD, XPS and magnetic measurements. We demonstrate the application of the fundamental models modified to fit the experimental zero-field cooling magnetization data. We discuss the influence of the nanoparticle shell parameters (morphology, thickness, ligands) on the overall magnetic performance of the systems. The prepared nanoparticles were tested for the isolation of viral RNA from tissue samples infected with hepatitis E virus-HEV and from biofluid samples of SARS-CoV-2 positive patients. The efficiency of RNA isolation was quantified by RT-qPCR method.
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COVID-19 , Nanopartículas de Magnetita , RNA Viral , SARS-CoV-2 , Dióxido de Silício , Dióxido de Silício/química , Humanos , Nanopartículas de Magnetita/química , RNA Viral/genética , RNA Viral/isolamento & purificação , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/virologia , Propriedades de Superfície , Patologia Molecular/métodos , Viroses/diagnóstico , Viroses/virologiaRESUMO
OBJECTIVES: This study aimed to examine the psychometric properties of the P4 suicide screener in a multinational sample. The primary goal was to evaluate the reliability and validity of the scale and investigate its convergent validity by analyzing its correlation with depression, anxiety, and substance use. STUDY DESIGN: The study design is a cross-sectional self-report study conducted across 42 countries. METHODS: A cross-sectional, self-report study was conducted in 42 countries, with a total of 82,243 participants included in the final data set. RESULTS: The study provides an overview of suicide ideation rates across 42 countries and confirms the structural validity of the P4 screener. The findings indicated that sexual and gender minority individuals exhibited higher rates of suicidal ideation. The P4 screener showed adequate reliability, convergence, and discriminant validity, and a cutoff score of 1 is recommended to identify individuals at risk of suicidal behavior. CONCLUSIONS: The study supports the reliability and validity of the P4 suicide screener across 42 diverse countries, highlighting the importance of using a cross-cultural suicide risk assessment to standardize the identification of high-risk individuals and tailoring culturally sensitive suicide prevention strategies.
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Comparação Transcultural , Ideação Suicida , Humanos , Estudos Transversais , Psicometria , Reprodutibilidade dos Testes , Prevenção do SuicídioRESUMO
Characterization of the aromatic ammonia-lyase from Loktanella atrilutea (LaAAL) revealed reduced activity towards canonical AAL substrates: l-Phe, l-Tyr, and l-His, contrasted by its pronounced efficiency towards 3,4-dimethoxy-l-phenylalanine. Assessing the optimal conditions, LaAAL exhibited maximal activity at pHâ 9.5 in the ammonia elimination reaction route, distinct from the typical pH ranges of most PALs and TALs. Within the exploration of the ammonia source for the opposite, synthetically valuable ammonia addition reaction, the stability of LaAAL exhibited a positive correlation with the ammonia concentration, with the highest stability in 4â M ammonium carbamate of unadjusted pH of ~9.5. While the enzyme activity increased with rising temperatures yet, the highest operational stability and highest stationary conversions of LaAAL were observed at 30 °C. The substrate scope analysis highlighted the catalytic adaptability of LaAAL in the hydroamination of diverse cinnamic acids, especially of meta-substituted and di-/multi-substituted analogues, with structural modelling exposing steric clashes between the substrates' ortho-substituents and catalytic site residues. LaAAL showed a predilection for ammonia elimination, while classifying as a tyrosine ammonia-lyase (TAL) among the natural AAL classes. However, its distinctive attributes, such as genomic context, unique substrate specificity and catalytic fingerprint, suggest a potential natural role beyond those of known AAL classes.
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Amônia-Liases , Biocatálise , Amônia-Liases/metabolismo , Amônia-Liases/química , Especificidade por Substrato , Amônia/metabolismo , Amônia/química , Concentração de Íons de Hidrogênio , Domínio Catalítico , Modelos MolecularesRESUMO
Among various metal-organic frameworks (MOFs), the zeolitic imidazole framework (ZIF), constructed by the regular arrangement of 2-methylimidazole and metal ions, has garnered significant attention due to its distinctive crystals and pore structures. Variations in the sizes and shapes of ZIF crystals have been reported by changing the synthesis parameters, such as the molar ratios of organic ligands to metal ions, choice of solvents, and temperatures. Nonetheless, the giant ZIF-8 single crystals beyond the typical range have rarely been reported. Herein, we present the synthesis of millimeter-scale single crystal ZIF-8 using the solvothermal method in N,N-diethylformamide. The resulting 1-mm single crystal is carefully characterized through N2 adsorption-desorption isotherms, scanning electron microscopy, and other analytical techniques. Additionally, single-crystal X-ray diffraction is employed to comprehensively investigate the framework's mobility at various temperatures.
Millimeter-sized ZIF-8 single crystals were synthesized using the solvothermal method. These crystals exhibit a notable BET surface area of 1681 m2âg−1 and demonstrate a reversible change in their crystal structure.
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Endothelial dysfunction is a leading cause of corneal blindness in developed countries and the only available treatment is the endothelial transplantation. However, the limited availability of suitable donors remains a significant challenge, driving the exploration of alternative regenerative therapies. Advanced Therapy Medicinal Products show promise but must adhere to strict regulations that prohibit the use of animal-derived substances. This study investigates a novel culture methodology using Plasma Rich in Growth Factors (PRGF) as the only source of growth factors for primary cultures of human corneal endothelial cells (CECs). CECs were obtained from discarded corneas or endothelial rings and cultured in two different media: one supplemented with xenogeneic factors and other xenogeneic-free, using PRGF. Comprehensive characterization through immunofluorescence, morphological analyses, trans-endothelial electrical resistance measurements, RNA-seq, and qPCR was conducted on the two groups. Results demonstrate that CECs cultured in the xenogeneic-free medium exhibit comparable gene expression, morphology, and functionality to those cultured in the xenogeneic medium. Notably, PRGF-expanded CECs share 46.9% of the gene expression profile with native endothelium and express all studied endothelial markers. In conclusion, PRGF provides an effective source of xenogeneic-free growth factors for the culture of CECs from discarded corneal tissue. Further studies will be necessary to demonstrate the applicability of these cultures to cell therapies that make clinical translation possible.
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Células Endoteliais , Endotélio Corneano , Animais , Humanos , Células Endoteliais/metabolismo , Córnea/metabolismo , Terapia Baseada em Transplante de Células e Tecidos , Células CultivadasRESUMO
Fruiting bodies (sporocarps, sporophores or basidiomata) of mushroom-forming fungi (Agaricomycetes) are among the most complex structures produced by fungi. Unlike vegetative hyphae, fruiting bodies grow determinately and follow a genetically encoded developmental program that orchestrates their growth, tissue differentiation and sexual sporulation. In spite of more than a century of research, our understanding of the molecular details of fruiting body morphogenesis is still limited and a general synthesis on the genetics of this complex process is lacking. In this paper, we aim at a comprehensive identification of conserved genes related to fruiting body morphogenesis and distil novel functional hypotheses for functionally poorly characterised ones. As a result of this analysis, we report 921 conserved developmentally expressed gene families, only a few dozens of which have previously been reported to be involved in fruiting body development. Based on literature data, conserved expression patterns and functional annotations, we provide hypotheses on the potential role of these gene families in fruiting body development, yielding the most complete description of molecular processes in fruiting body morphogenesis to date. We discuss genes related to the initiation of fruiting, differentiation, growth, cell surface and cell wall, defence, transcriptional regulation as well as signal transduction. Based on these data we derive a general model of fruiting body development, which includes an early, proliferative phase that is mostly concerned with laying out the mushroom body plan (via cell division and differentiation), and a second phase of growth via cell expansion as well as meiotic events and sporulation. Altogether, our discussions cover 1 480 genes of Coprinopsis cinerea, and their orthologs in Agaricus bisporus, Cyclocybe aegerita, Armillaria ostoyae, Auriculariopsis ampla, Laccaria bicolor, Lentinula edodes, Lentinus tigrinus, Mycena kentingensis, Phanerochaete chrysosporium, Pleurotus ostreatus, and Schizophyllum commune, providing functional hypotheses for ~10 % of genes in the genomes of these species. Although experimental evidence for the role of these genes will need to be established in the future, our data provide a roadmap for guiding functional analyses of fruiting related genes in the Agaricomycetes. We anticipate that the gene compendium presented here, combined with developments in functional genomics approaches will contribute to uncovering the genetic bases of one of the most spectacular multicellular developmental processes in fungi. Citation: Nagy LG, Vonk PJ, Künzler M, Földi C, Virágh M, Ohm RA, Hennicke F, Bálint B, Csernetics Á, Hegedüs B, Hou Z, Liu XB, Nan S, M. Pareek M, Sahu N, Szathmári B, Varga T, Wu W, Yang X, Merényi Z (2023). Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes. Studies in Mycology 104: 1-85. doi: 10.3114/sim.2022.104.01.
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In the present study, an eco-friendly method for the preparation of carbon quantum dots (CQDs) is demonstrated using hydrothermal treatment of laurel leaves. The optical and structural characteristics of the prepared CQDs are investigated using transmission electron microscopy (TEM), X-ray photoelectron (XPS), fluorescent and UV-visible spectroscopies, Fourier transform infrared (FTIR), and X-ray diffraction (XRD). The quartz crystal microbalance (QCM) sensor designed and modified with CQDs is capable of detecting formaldehyde vapors in the presence of other interfering chemical-vapor analytes. The changes in the frequency of the QCM sensor are linearly correlated with the injected formaldehyde concentrations. The sensing properties of formaldehyde, including sensitivity and reversibility, are investigated. Detection of formaldehyde in the presence of humidity is carefully discussed for home or workplace room environment use. The adsorption kinetics of various VOCs vapors are also calculated and discussed.
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Pontos Quânticos , Pontos Quânticos/química , Carbono/química , Técnicas de Microbalança de Cristal de Quartzo , Microscopia Eletrônica de Transmissão , FormaldeídoRESUMO
The purpose of this review is to outline our understanding of the nature, mechanism and physiological significance of light-induced reversible reorganizations in closed Type II reaction centre (RC) complexes. In the so-called 'closed' state, purple bacterial RC (bRC) and photosystem II (PSII) RC complexes are incapable of generating additional stable charge separation. Yet, upon continued excitation they display well-discernible changes in their photophysical and photochemical parameters. Substantial stabilization of their charge-separated states has been thoroughly documented-uncovering light-induced reorganizations in closed RCs and revealing their physiological importance in gradually optimizing the operation of the photosynthetic machinery during the dark-to-light transition. A range of subtle light-induced conformational changes has indeed been detected experimentally in different laboratories using different bRC and PSII-containing preparations. In general, the presently available data strongly suggest similar structural dynamics of closed bRC and PSII RC complexes, and similar physical mechanisms, in which dielectric relaxation processes and structural memory effects of proteins are proposed to play important roles.
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Fotossíntese , Complexo de Proteína do Fotossistema II , Complexo de Proteína do Fotossistema II/metabolismoRESUMO
Formic acid (HCOOH) is an important intermediate in chemical synthesis, pharmaceuticals, the food industry, and leather tanning and is considered to be an effective hydrogen storage molecule. Direct contact with its vapor and its inhalation lead to burns, nerve injury, and dermatosis. Thus, it is critical to establish efficient sensing materials and devices for the rapid detection of HCOOH. In the present study, we introduce a chemical sensor based on a quartz crystal microbalance (QCM) sensor capable of detecting trace amounts of HCOOH. This sensor is composed of colloidal phenyl-terminated carbon nitride (Ph-g-C3N4) quantum nanoflakes prepared using a facile solid-state method involving the supramolecular preorganization technology. In contrast to other synthetic methods of modified carbon nitride materials, this approach requires no hard templates, hazardous chemicals, or hydrothermal treatments. Comprehensive characterization and density functional theory (DFT) calculations revealed that the QCM sensor designed and prepared here exhibits enhanced detection sensitivity and selectivity for volatile HCOOH, which originates from chemical and hydrogen-bonding interactions between HCOOH and the surface of Ph-g-C3N4. According to DFT results, HCOOH is located close to the cavity of the Ph-g-C3N4 unit, with bonding to graphitic carbon and pyridinic nitrogen atoms of the nanoflake. The sensitivity of the Ph-g-C3N4-nanoflake-based QCM sensor was found to be the highest (128.99 Hz ppm-1) of the substances studied, with a limit of detection (LOD) of HCOOH down to a sub-ppm level of 80 ppb. This sensing technology based on phenyl-terminated attached-g-C3N4 nanoflakes establishes a simple, low-cost solution to improve the performance of QCM sensors for the effective discrimination of HCOOH, HCHO, and CH3COOH vapors using smart electronic noses.
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The present study aimed to develop a reliable dynamic measurement technique, which can be used directly in the outpatient setting, based on dorsal subluxation of the scaphoid on scaphoid shift test. This study was designed to evaluate feasibility and to quantify dorsal subluxation of the scaphoid in relation to the lunate. Based on a scaphoid shift test under ultrasonography, a standardized 3D test model was developed to measure subluxation. Sagittal subluxation ranged between 0 and 6 mm, as checked on the implemented scale. Four hand surgeons trained in ultrasonography (experience level II-V) performed blinded measurements (total of 52, n = 13 per investigator) with a standardized measurement protocol. Dorsal subluxation of the scaphoid was measured in relation to the lunate. Interobserver reliability on intraclass correlation coefficient (ICC) was excellent, at 0.97 (95% confidence interval, 0.930-0.992). Mean overall absolute measurement error was 0.27 mm ± 0.21. Dorsal subluxation of the scaphoid can thus be accurately measured on ultrasound with excellent interobserver reliability, quantifying and improving clinical assessment of scapholunate instability.
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Instabilidade Articular , Ligamentos Articulares , Estudos de Viabilidade , Humanos , Instabilidade Articular/cirurgia , Ligamentos Articulares/cirurgia , Reprodutibilidade dos Testes , UltrassonografiaRESUMO
BACKGROUND: Intra-articular fractures are associated with posttraumatic arthritis if inappropriately treated. Exact reduction of the joint congruency is the main factor to avoid the development of arthrosis. Aim of this study was to evaluate feasibility of computer-assisted surgical planning and 3D-printed patient-specific instrumentation (PSI) for treatment of distal intraarticular radius fractures. METHOD: 7 Patients who suffered a distal intraarticular radius fracture were enrolled in this prospective case series. Preoperative CT-scan was recorded, whereupon a 3D model was computed for surgical planning and design of PSI for surgical navigation. Postoperative accuracy and joint congruency were assessed. Patients were followed-up 3, 6 and 12 months postoperatively. RESULTS: Mean follow-up was 16 months. Over all range of motion was restored and flexion, extension and pronation showed significant recovery, p < 0.05. Biggest intraarticular joint step-off and gap reduced from average 2.49 (± 1.04) to 0.8 mm (± 0.44), p < 0.05 and 6.12 mm (± 1.04) to 2.21 mm (± 1.16), p < 0.05. Average grip strength restored (3-16 months) from 20.33 kg (± 7.12) to 39.3 kg (± 19.55) p < 0.05, 100% of the healthy contralateral side. 3D-accuracy for guided fragments was 2.07 mm (± 0.64) and 8.59° (± 2.9) and 2.33 mm (± 0.69) and 12.86° (± 7.13), p > 0.05 for fragments reduced with ligamentotaxis. CONCLUSION: Computer-assisted and PSI navigated intraarticular radius fracture treatment is feasible, safe and accurate. The benefits of this method, however, do not outstand the additional effort. LEVEL OF EVIDENCE: IV.
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Fraturas Intra-Articulares , Fraturas do Rádio , Adolescente , Adulto , Idoso , Placas Ósseas , Computadores , Feminino , Fixação Interna de Fraturas , Humanos , Fraturas Intra-Articulares/diagnóstico por imagem , Fraturas Intra-Articulares/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Amplitude de Movimento Articular , Cirurgia Assistida por Computador , Resultado do TratamentoRESUMO
Metal-organic frameworks (MOFs) are a versatile source of carbon nanoarchitectures in gas sensing applications (Torad et al., 2019). Herein, several types of nanoporous carbons (NPCs) have been prepared by in-situ carbothermal treatment of zeolitic imidazolate frameworks (ZIFs) under different inert atmospheres to achieve a highly sensitive discrimination of vaporized aromatic compounds. In this study, we demonstrate how different carbonization conditions under the flow of N2 or H2 gases affect the surface area and the degree of graphitization of the resulting NPCs polyhedrons, and their consequent effect on the sensing performance in terms of sensitivity and selectivity toward toxic volatile hydrocarbons. A growth of carbon nanotubes (CNTs) is observed on the surface of polyhedral NPCs after careful carbonization of ZIF crystals under H2 atmosphere. The fabricated quartz crystal microbalance (QCM) sensor with CNT-containing NPCs demonstrates increased sensitivity and selectivity towards toxic volatile aromatic hydrocarbons over the aliphatic analogues, suggesting the rich growth of hairy graphitic-like CNTs on the surface of carbon framework act as highly selective sensing antennae for vapor molecular discrimination of toxic aromatic hydrocarbons. Despite of increased selectivity towards volatile aromatic compounds, however, the surface area of CNT-rich NPCs derived from hybrid ZIFs and ZIF-67 is greatly sacrificed as compared to CNT-free NPCs from ZIF-8 polyhedron. In the case of Co-containing ZIF-67, the rich growth of hair-like CNTs, which is induced by the presence of Co, is observed during carbothermal reduction under a flow of H2 gas, thus allowing ultra-selective detection of aromatic hydrocarbons in the vapor phase, such as benzene (C6H6) and toluene (C6H5CH3) over their aliphatic analogue, c-hexane (c-C6H12) of same molecular mass, size and vapor pressure.
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Constructing heterostructures with advanced architectures is an effective strategy for enhancing the crystallinity and functional performance of covalent organic frameworks (COFs). Herein, a novel core-shell heterostructure integrating a metal-organic framework (MOF)-derived graphitic carbon core (GC) and a well-arranged COF shell, termed MOF-GC@COF, is reported. ZIF-67 dodecahedra are first chemically etched with a weak organic acid and further converted to MOF-GC via thermal pyrolysis. In the subsequent step, ß-ketoenamine-linked COF nanofibers are vertically assembled on the surface of the MOF-GC cores to generate the MOF-GC@COF heterostructure. As a proof-of-concept application, the as-prepared MOF-GC@COF heterostructure is used as an effective quartz crystal microbalance (QCM) sensor for the adsorption of formaldehyde. Benefiting from the synergistic effect of the hybrid composition and the advantages of the core-shell heterostructure, the newly prepared MOF-GC@COF heterostructure exhibits excellent sensing performance toward formaldehyde with rapid adsorption kinetics, high sensitivity, and superior selectivity.
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Malunions of the forearm and hand cause significant disability. Moreover, intraarticular deformities may contribute to early onset osteoarthritis. Such conditions require precise surgical correction in order to improve functional outcomes and prevent early or late complications. The purpose of this study was to describe the technical advantages of accurate anatomical reconstruction using 3D guided osteotomies and patient specific instruments (PSI) in multiple joints of the hand and forearm. Acquisition of three-dimensional (3D) datasets and surgical implementation of PSI was performed in a series of patients between December 2014 and July 2017. Patients had intra- or extra-articular malunions of the forearm, radiocarpal joint, trapeziometacarpal joint, or proximal interphalangeal joint. A previously described 3D surface model that incorporates CT data was used for segmentation (Mimics®, Materialise™, Belgium). For all the cases, CT scans of both forearms were acquired to use the contralateral uninjured side as the anatomic reconstruction template. Computer-assisted assessment of the deformity, the preoperative plan, and the design of PSI are described. Outcomes were determined by evaluating step-off correction, fusion, changes in range of motion (ROM) and grip strength. Six patients were included in the study; all achieved fusion. Improved clinical outcomes including pain reduction, better ROM and grip strength were obtained. Complete correction of intraarticular step-off was achieved in all cases with intraarticular malunions. 3D guided osteotomies are an established surgical treatment option for malunions of the hand and forearm. 3D analysis is a helpful diagnostic tool that provides detailed information about the underlying deformity. PSI can be developed and used for surgical correction with maximal accuracy for both intraarticular step-off and angular deformity.
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Articulações do Carpo/cirurgia , Articulações dos Dedos/cirurgia , Fraturas Mal-Unidas/cirurgia , Imageamento Tridimensional , Cirurgia Assistida por Computador , Articulação do Punho/cirurgia , Adolescente , Adulto , Articulações do Carpo/diagnóstico por imagem , Feminino , Articulações dos Dedos/diagnóstico por imagem , Fraturas Mal-Unidas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Osteotomia , Cuidados Pré-Operatórios , Estudos Retrospectivos , Articulação do Punho/diagnóstico por imagem , Adulto JovemRESUMO
BACKGROUND: Branched-chain amino acid (BCAA) concentrations must be tracked and maintained within an optimal range to minimize disease phenotypes in patients with maple syrup urine disease (MSUD). In 2014, the Hospital for Sick Children (SickKids) implemented a dried blood spot (DBS) home monitoring system, allowing patients to track BCAA concentrations without the inconvenience of having to travel to the hospital. METHODS: We conducted a retrospective chart review study (nâ¯=â¯15) to assess the impacts of DBS monitoring implementation on biochemical control. Furthermore, we explored relationships among various MSUD patient parameters, including monitoring frequency, age, biochemical control, and hospitalizations. RESULTS: There was a 35% increase in the proportion of LEU concentrations that met recommended targets post-DBS monitoring implementation. Monitoring frequency was positively associated with better biochemical control in the newborn period (râ¯=â¯0.68, pâ¯=â¯0.046). Frequency of hospital visits decreased steadily throughout life. CONCLUSION: DBS monitoring has resulted in a sharp increase in monitoring frequency, which is further correlated with biochemical control. Younger patients are more likely to visit the hospital and respond better to increased monitoring efforts. We recommend that DBS monitoring be adopted by other centers more broadly to improve metabolic control in MSUD patients.
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Aminoácidos de Cadeia Ramificada/sangue , Teste em Amostras de Sangue Seco , Doença da Urina de Xarope de Bordo/sangue , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Doença da Urina de Xarope de Bordo/terapia , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
2D transition metal dichalcogenides (TMDs) have received widespread interest by virtue of their excellent electrical, optical, and electrochemical characteristics. Recent studies on TMDs have revealed their versatile utilization as electrocatalysts, supercapacitors, battery materials, and sensors, etc. In this study, MoS2 nanosheets are successfully assembled on the porous VS2 (P-VS2 ) scaffold to form a MoS2 /VS2 heterostructure. Their gas-sensing features, such as sensitivity and selectivity, are investigated by using a quartz crystal microbalance (QCM) technique. The QCM results and density functional theory (DFT) calculations reveal the impressive affinity of the MoS2 /VS2 heterostructure sensor toward ammonia with a higher adsorption uptake than the pristine MoS2 or P-VS2 sensor. Furthermore, the adsorption kinetics of the MoS2 /VS2 heterostructure sensor toward ammonia follow the pseudo-first-order kinetics model. The excellent sensing features of the MoS2 /VS2 heterostructure render it attractive for high-performance ammonia sensors in diverse applications.
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Hard- and soft-templating approaches are one of potential strategies for the fabrication of functional nanoporous carbon materials with desired morphologies and properties. Enormous efforts have been paid for understanding the synthetic mechanisms that strongly influence the materials design and applications. All of these investigations are crucial to encourage the application of hard- and soft-templating approaches for the precise synthesis of nanoporous carbon materials. In this review, we mainly summarize significant works employing different synthetic methods for making carbon materials with various pore sizes and functionalities. The content of the review article contains: (i) Hard-templating synthesis of microporous carbon from zeolites; (ii) Hard-templating synthesis of mesoporous carbon from mesoporous silica; (iii) Hard-templating synthesis of macroporous carbon; and (iv) Soft-templating synthesis of mesoporous carbon. This review aims to provide a detailed glimpse of hard- and soft-templating approaches for future development of functional nanoporous carbon materials.
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Functionalization of mesoporous silica KIT-6 with ß-cyclodextrin (ß-CD) was successfully realized via post-grafting method as a new adsorbent for environmental remediation of methylene blue (MB) dye from aqueous solutions. The mesostructure properties were characterized by transmission electron microscope (TEM), low-angel X-ray diffraction (XRD), Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA) and N2 sorption isotherm. The remarkable adsorption of MB into ß-CD-KIT-6 adsorbent was studied using UV-visible spectroscopy. The ß-CD-KIT-6 exhibited higher adsorption capacity compared with unmodified-KIT-6. The adsorption behavior of MB into the ß-CD-KIT-6 and unmodified-KIT-6 was carefully investigated using different kinetic and isotherm models. The adsorption process followed a pseudo-second order kinetic model and well-fitted to Langmuir isotherm. The thermodynamic parameters were evaluated and the adsorption of MB was found to be an exothermic and spontaneous process. The adsorption of MB into the ß-CD-KIT-6 was highly dependent on the solution pH.
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Conjugated linoleic acid (CLA) has been shown to activate the nuclear receptor PPAR-γ and modulate metabolic and immune functions. Despite the worldwide use of CLA dietary supplementation, strong scientific evidence for its proposed beneficial actions are missing. We found that CLA-supplemented diet reduced mucosal damage and inflammatory infiltrate in the dextran sodium sulfate (DSS)-induced colitis model. Conditional deletion of PPAR-γ in macrophages from mice supplemented with CLA diet resulted in loss of this protective effect of CLA, suggesting a PPAR-γ-dependent mechanism mediated by macrophages. However, CLA supplementation significantly worsened colorectal tumor formation induced by azoxymethane and DSS by inducing macrophage and T-cell-producing TGF-ß via PPAR-γ activation. Accordingly, either macrophage-specific deletion of PPAR-γ or in vivo neutralization of latency-associated peptide (LAP, a membrane-bound TGF-ß)-expressing cells abrogated the protumorigenic effect of CLA. Thus, the anti-inflammatory properties of CLA are associated with prevention of colitis but also with development of colorectal cancer.
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Colite/imunologia , Neoplasias Colorretais/imunologia , Doenças Inflamatórias Intestinais/imunologia , Ácidos Linoleicos Conjugados/metabolismo , Macrófagos/imunologia , PPAR gama/metabolismo , Linfócitos T/imunologia , Ácido Aminossalicílico/metabolismo , Animais , Carcinogênese , Células Cultivadas , Colite/induzido quimicamente , Neoplasias Colorretais/induzido quimicamente , Sulfato de Dextrana , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , PPAR gama/genética , Fator de Crescimento Transformador beta/metabolismoRESUMO
OBJECTIVE/BACKGROUND: Asymmetric dimethylarginine (ADMA) inhibits nitric oxide (NO) synthesis and is a marker of atherosclerosis. This study examined the correlation between pre-operative l-arginine and ADMA concentration during carotid endarterectomy (CEA), and jugular lactate indicating anaerobic cerebral metabolism, jugular S100B reflecting blood-brain barrier integrity, and with factors of surgical intervention. METHODS: The concentration of l-arginine, ADMA, and symmetric dimethylarginine was measured in blood taken under regional anaesthesia from the radial artery of 55 patients prior to CEA. Blood gas parameters, concentration of lactate, and S100B were also serially measured in blood taken from both the radial artery and the jugular bulb before and after carotid clamping, and after release of the clamp. To estimate anaerobic metabolism, the jugulo-arterial ratio of CO2 gap/oxygen extraction was calculated. RESULTS: Positive correlation was found between pre-operative ADMA levels and the ratio of jugulo-arterial CO2 gap/oxygen extraction during clamp and reperfusion (p = .005 and p = .01, respectively). An inverse correlation was found between the pre-operative l-arginine concentration and jugular lactate at each time point (both p = .002). The critical pre-operative level of l-arginine was determined by receiver operator curve analysis. If l-arginine was below the cutoff value of 35 µmol/L, jugular S100B concentration was higher 24 h post-operatively (p = .03), and jugular lactate levels were increased during reperfusion (p = .02). The median pre-operative concentration of l-arginine was lower in patients requiring an intra-operative shunt than in patients without need of shunt (median: 30.3 µmol/L [interquartile range 24.4-34.4 µmol/L] vs. 57.6 µmol/L [interquartile range 42.3-74.5 µmol/L]; p = .002). CONCLUSION: High pre-operative ADMA concentration predicts poor cerebral perfusion indicated by elevated jugulo-arterial CO2 gap/oxygen extraction. Low pre-operative l-arginine concentration predicts the need for a shunt. The inverse correlation between pre-operative l-arginine concentration and both jugular lactate and S100B during carotid clamping suggests a protective role of the NO donor l-arginine.