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2.
Analyst ; 149(3): 947-957, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38197180

RESUMO

The construction of a new electrochemical sensing platform based on a copper metal-organic framework (Cu-MOF) heterostructure is described in this paper. Drop-casting Cu-MOF suspension onto the electrode surface primed the sensor for glutathione detection. The composition and morphology of the Cu-MOF heterostructure were investigated using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FT-IR), and UV-visible spectroscopy. The Cu-MOF heterostructure can identify glutathione (GSH) with an enhanced sensitivity of 0.0437 µA µM-1 at the detection limit (LOD; 0.1 ± 0.005 µM) and a large dynamic range of 0.1-20 µM. Boosting the conductivity and surface area enhances electron transport and promotes redox processes. The constructed sensors were also adequately selective against interference from other contaminants in a similar potential window. Furthermore, the Cu-MOF heterostructure has outstanding selectivity, long-term stability, and repeatability, and the given sensors have demonstrated their capacity to detect GSH with high accuracy (recovery range = 98.2-100.8%) in pharmaceutical samples.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Cobre/química , Estruturas Metalorgânicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Preparações Farmacêuticas , Técnicas Eletroquímicas
3.
Molecules ; 28(23)2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38067644

RESUMO

Contaminants of Emerging Concern (CECs), a new category of contaminants currently in the limelight, are a major issue of global concern. The pervasive nature of CECs and their harmful effects, such as cancer, reproductive disorders, neurotoxicity, etc., make the situation alarming. The perilous nature of CECs lies in the fact that even very small concentrations of CECs can cause great impacts on living beings. They also have a nature of bioaccumulation. Thus, there is a great need to have efficient sensors for the detection of CECs to ensure a safe living environment. Electrochemical sensors are an efficient platform for CEC detection as they are highly selective, sensitive, stable, reproducible, and prompt, and can detect very low concentrations of the analyte. Major classes of CECs are pharmaceuticals, illicit drugs, personal care products, endocrine disruptors, newly registered pesticides, and disinfection by-products. This review focusses on CECs, including their sources and pathways, health effects caused by them, and electrochemical sensors as reported in the literature under each category for the detection of major CECs.


Assuntos
Praguicidas , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Praguicidas/análise , Monitoramento Ambiental
4.
PLoS One ; 18(12): e0296470, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38157362

RESUMO

While systemic corticosteroids quicken patient recovery during acute exacerbations of COPD, they also have many adverse effects. The optimal duration of corticosteroid administration remains uncertain. We performed a systematic review and meta-analysis to compare patient outcomes between short- (≤7 days) and long- (>7 days) corticosteroid regimens in adults with acute exacerbations of COPD. MEDLINE, EMBASE, CENTRAL, and hand searches were used to identify eligible studies. Risk of bias was assessed using the Cochrane RoB 2.0 tool and ROBINS-I. Data were summarized as ORs (odds ratios) or MDs (mean differences) whenever possible and qualitatively described otherwise. A total of 11532 participants from eight RCTs and three retrospective cohort studies were included, with 1296 from seven RCTs and two cohort studies eligible for meta-analyses. Heterogeneity was present in the methodology and settings of the studies. The OR (using short duration as the treatment arm) for mortality was 0.76 (95% CI = 0.40-1.44, n = 1055). The MD for hospital length-of-stay was -0.91 days (95% CI = -1.81--0.02 days, n = 421). The OR for re-exacerbations was 1.31 (95% CI = 0.90-1.90, n = 552). The OR for hyperglycemia was 0.90 (95% CI = 0.60-1.33, n = 423). The OR for infection incidence was 0.96 (95% CI = 0.59-1.156, n = 389). The MD for one-second forced expiratory volume change was -18.40 mL (95% CI = -111.80-75.01 mL, n = 161). The RCTs generally had low or unclear risks of bias, while the cohort studies had serious or moderate risks of bias. Our meta-analyses were affected by imprecision due to insufficient data. Some heterogeneity was present in the results, suggesting population, setting, and treatment details are potential prognostic factors. Our evidence suggests that short-duration treatments are not worse than long-duration treatments in moderate/severe exacerbations and may lead to considerably better outcomes in milder exacerbations. This supports the current GOLD guidelines. Trial registration: Our protocol is registered in PROSPERO: CRD42023374410.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Adulto , Humanos , Estudos Retrospectivos , Progressão da Doença , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Corticosteroides/uso terapêutico
5.
Materials (Basel) ; 16(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38004995

RESUMO

Super-sensitive malathion detection was achieved using a nonenzymatic electrochemical sensor based on a CuO/ZnO-modified glassy carbon electrode (GCE). Due to the high affinity between the Cu element and the sulfur groups in malathion, the developed CuO-ZnO/GCE sensor may bond malathion with ease, inhibiting the redox signal of the Cu element when malathion is present. In addition to significantly increasing the ability of electron transfer, the addition of 3D-flower-like ZnO enhances active sites of the sensor interface for the high affinity of malathion, giving the CuO-ZnO/GCE composite an exceptional level of sensitivity and selectivity. This enzyme-free CuO-ZnO/GCE malathion sensor demonstrates outstanding stability and excellent detection performance under optimal operating conditions with a wide linear range of malathion from 0 to 200 nM and a low detection limit of 1.367 nM. A promising alternative technique for organophosphorus pesticide (OP) determination is offered by the analytical performance of the proposed sensor, and this method can be quickly and sensitively applied to samples that have been contaminated with these pesticides.

6.
Cell Rep Med ; 4(10): 101212, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37774704

RESUMO

Pediatric patients with relapsed or refractory rhabdomyosarcoma (RMS) have dismal cure rates, and effective therapy is urgently needed. The oncogenic receptor tyrosine kinase fibroblast growth factor receptor 4 (FGFR4) is highly expressed in RMS and lowly expressed in healthy tissues. Here, we describe a second-generation FGFR4-targeting chimeric antigen receptor (CAR), based on an anti-human FGFR4-specific murine monoclonal antibody 3A11, as an adoptive T cell treatment for RMS. The 3A11 CAR T cells induced robust cytokine production and cytotoxicity against RMS cell lines in vitro. In contrast, a panel of healthy human primary cells failed to activate 3A11 CAR T cells, confirming the selectivity of 3A11 CAR T cells against tumors with high FGFR4 expression. Finally, we demonstrate that 3A11 CAR T cells are persistent in vivo and can effectively eliminate RMS tumors in two metastatic and two orthotopic models. Therefore, our study credentials CAR T cell therapy targeting FGFR4 to treat patients with RMS.


Assuntos
Receptores de Antígenos Quiméricos , Rabdomiossarcoma , Animais , Criança , Humanos , Camundongos , Linhagem Celular Tumoral , Imunoterapia Adotiva , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Receptores de Antígenos Quiméricos/genética , Rabdomiossarcoma/tratamento farmacológico
7.
Cancers (Basel) ; 15(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37627061

RESUMO

Rhabdomyosarcoma (RMS) is the most common pediatric soft tissue sarcoma. Despite decades of clinical trials, the overall survival rate for patients with relapsed and metastatic disease remains below 30%, underscoring the need for novel treatments. FGFR4, a receptor tyrosine kinase that is overexpressed in RMS and mutationally activated in 10% of cases, is a promising target for treatment. Here, we show that futibatinib, an irreversible pan-FGFR inhibitor, inhibits the growth of RMS cell lines in vitro by inhibiting phosphorylation of FGFR4 and its downstream targets. Moreover, we provide evidence that the combination of futibatinib with currently used chemotherapies such as irinotecan and vincristine has a synergistic effect against RMS in vitro. However, in RMS xenograft models, futibatinib monotherapy and combination treatment have limited efficacy in delaying tumor growth and prolonging survival. Moreover, limited efficacy is only observed in a PAX3-FOXO1 fusion-negative (FN) RMS cell line with mutationally activated FGFR4, whereas little or no efficacy is observed in PAX3-FOXO1 fusion-positive (FP) RMS cell lines with FGFR4 overexpression. Alternative treatment modalities such as combining futibatinib with other kinase inhibitors or targeting FGFR4 with CAR T cells or antibody-drug conjugate may be more effective than the approaches tested in this study.

8.
Molecules ; 28(14)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37513259

RESUMO

Carbon materials with elusive 0D, 1D, 2D, and 3D nanostructures and high surface area provide certain emerging applications in electrocatalytic and photocatalytic CO2 utilization. Since carbon possesses high electrical conductivity, it expels the photogenerated electrons from the catalytic surface and can tune the photocatalytic activity in the visible-light region. However, the photocatalytic efficiency of pristine carbon is comparatively low due to the high recombination of photogenerated carriers. Thus, supporting carbon materials, such as graphene, CNTs (Carbon nanotubes), g-C3N4, MWCNs (Multiwall carbon nanotubes), conducting polymers, and its other simpler forms like activated carbon, nanofibers, nanosheets, and nanoparticles, are usually combined with other metal and non-metal nanocomposites to increase the CO2 absorption and conversion. In addition, carbon-based materials with transition metals and organometallic complexes are also commonly used as photocatalysts for CO2 reduction. This review focuses on developing efficient carbon-based nanomaterials for the photoconversion of CO2 into solar fuels. It is concluded that MWCNs are one of the most used materials as supporting materials for CO2 reduction. Due to the multi-layered morphology, multiple reflections will occur within the layers, thus enhancing light harvesting. In particular, stacked nanostructured hollow sphere morphologies can also help the metal doping from corroding.

9.
Can J Public Health ; 114(5): 840-855, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165142

RESUMO

OBJECTIVES: The aims of the study are to identify trends in the socio-demographic, health, and work profiles of Canadian carer-employees (CEs) over time, as well as the gender difference in the intensity of caring. METHODS: Cross-sectional data from cycles 26 and 32, collected in 2012 and 2018 respectively, of the Canadian General Social Survey (GSS) were used. Logistic, multinomial logistic, and linear regressions were used to estimate how caregiving is associated with caregivers' health, well-being, and work in both cycles. Regressions from both cycles were then compared with chi-square tests for significant differences over time. RESULTS: The proportion of male CEs grew between 2012 and 2018, and women were no longer more likely to be a CE. The intensity of care for female CEs was significantly increased from 2012 to 2018 as compared with their male counterparts. General health (2018: OR = 0.25[0.11, 0.61] vs. 2012: OR = 0.33[0.15, 0.72]) and life satisfaction ([Formula: see text] = -0.42[0.54, -0.30] vs. [Formula: see text] = -0.22[-0.30, -0.14]) were significantly worsened with respect to the role of CEs from 2012 to 2018. CONCLUSION: Our study provides the evidence that CEs' health and well-being have worsened over time, especially for female CEs, indicating that the needs of CEs are growing at a faster rate than the supports available. The results are meaningful in informing and justifying the provision of CE supports at work in order to sustain CEs in the workplace, such as the carer-friendly workplace policies.


RéSUMé: OBJECTIFS: Notre étude vise à cerner les tendances du profil sociodémographique, sanitaire et professionnel des employés soignants (ES) canadiens au fil du temps, ainsi que les différences entre les sexes dans l'intensité des soins. MéTHODE: Nous avons utilisé les données transversales des cycles 26 et 32, collectées en 2012 et en 2018 respectivement, de l'Enquête sociale générale (ESG) du Canada. Nous avons fait appel à la régression logistique, à la régression logistique multinomiale et à la régression linéaire pour estimer les associations entre la prestation de soins et la santé, le bien-être et le travail des soignants lors des deux cycles. Nous avons ensuite comparé les régressions des deux cycles avec les analyses du khi-carré pour cerner les écarts significatifs dans le temps. RéSULTATS: La proportion d'ES de sexe masculin a augmenté entre 2012 et 2018, et les femmes n'affichaient plus une probabilité accrue d'être des ES. L'intensité des soins chez les ES de sexe féminin a augmenté de façon significative entre 2012 et 2018 comparativement à leurs homologues masculins. La santé générale (2018 : RC = 0,25[0,11, 0,61] vs 2012 : RC = 0,33[0,15, 0,72]) et la satisfaction à l'égard de la vie ([Formula: see text] = -0,42[0,54, -0,30] vs [Formula: see text] = -0,22[-0,30, -0,14]) se sont significativement dégradées en ce qui a trait au rôle des ES entre 2012 et 2018. CONCLUSION: Notre étude prouve que la santé et le bien-être des ES se sont dégradées au fil du temps, surtout chez les femmes, ce qui montre que les besoins des ES augmentent plus rapidement que le soutien disponible. Ces résultats contribueront à éclairer et à justifier la prestation de mesures d'aide aux ES afin de les appuyer dans leurs milieux de travail, comme par exemple des politiques conçues pour les soignants en milieu de travail.


Assuntos
Cuidadores , Local de Trabalho , Humanos , Masculino , Feminino , Estudos Transversais , Canadá , Condições de Trabalho
10.
Wellbeing Space Soc ; 4: 100123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36510579

RESUMO

The aim of this analysis is to assess the potential ways that the COVID-19 pandemic has impacted Canadian carer-employees (CEs) and identify the needs CEs feel is required for them to continue providing care. We assess the similarities and differences in the stresses CEs faced during COVID-19 globally across countries in the G7, Australia, Spain, Brazil, Taiwan, India, and China. We aim to compare Canada against global trends with respect to the challenges of the COVID-19 pandemic, as well as the supports in place for CEs. The study utilized 2020 Carer Well-Being Index at the country level. Descriptive data on Canadian CEs is first reviewed, followed by comparisons, by country, on responses relating to: (a) time spent caring; (b) sources of support; (c) impact on paid work and career, and; (d) emotional/mental, financial, and physical health. The relationship between government support and emotional/mental health is also explored. When compared to pre-pandemic times, CEs in Canada on average spent more time caregiving, with 34% reporting more difficulty balancing their paid job and caring responsibilities. Seventy-one percent of CEs feel their mental health has deteriorated. Thirty-four percent of Canadian CEs received support from the government, and only 30% received support from their employers. Globally, there was a similar trend, with CEs experiencing deteriorating mental health, work impacts, and unmet needs during the pandemic. Comparing the well-being of Canadian CEs with other countries provides an opportunity to evaluate areas where Canadian policies and programs have been effective, as well as areas needing improvement.

11.
Chemosphere ; 310: 136865, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36244422

RESUMO

Castor cake is a major by-product generated after castor oil extraction and has been widely used as an organic fertilizer. Once applied to soil, a toxic alkaloid ricinine in castor cake may be released into soils and subsequently taken up by crops, which poses a potential threat to food safety and human health. However, the environmental fate of castor cake derived ricinine in agroecosystems remains unclear. In this study, the release and metabolism of ricinine in soils were conducted using soil pot experiments with different castor cake application rates. The analytical methodology of ricinine quantification in soil pore water was first established using solid phase extraction (SPE) coupled with liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF/MS). A non-target screening workflow associated with LC-QTOF/MS and SIRIUS platform was further developed to identify ricinine metabolites in soil pore water. After castor cake application, the ricinine concentrations in soil pore water significantly increased to 297-7990 µg L-1 at 1 day and then gradually decreased to 62.1-3460 µg L-1 at 7 days and 1.70-279 µg L-1 at 14 days for the selected two tested soils with castor cake application rates of 2, 10, and 20 g castor cake/kg soil. In addition, two ricinine metabolites R-194 and R-180 were tentatively identified and one ricinine metabolite N-demethyl-ricinin was confirmed through authentic reference standard for the first time by the developed non-target screening workflow. This study highlights the release and metabolism of toxic alkaloid ricinine in soils once applied castor cake as an organic fertilizer. Ricinine could be released into soil pore water in a short-term after castor cake application and then undergo demethylation, hydroxylation, and hydroxylation followed by methylation metabolisms over time in agroecosystems.


Assuntos
Alcaloides , Fertilizantes , Humanos , Fertilizantes/análise , Solo , Óleo de Rícino , Fluxo de Trabalho , Cromatografia Líquida , Alcaloides/análise , Espectrometria de Massas , Água/análise
12.
Nanomaterials (Basel) ; 12(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36432216

RESUMO

Heavy metals are one of the most important classes of environmental pollutants which are toxic to living beings. Many efforts are made by scientists to fabricate better sensors for the identification and quantification of heavy metal ions (HMI) in water and food samples to ensure good health. Electrocatalysts have been demonstrated to play an important role in enhancing the sensitivity and selectivity of HMI detection in electrochemical sensors. In this review, we presented morphologically well-tuned nanomaterials used as efficient sensor materials. Based on the molecular dimensions, shapes, and orientation, nanomaterials can be classified into 0-D, 1-D, 2-D, and 3-D nanomaterials. Active surface areas with significant exposure of active sites and adsorption-desorption abilities are extensively varied with dimensionality, which in turn ultimately influence the sensing performance for HMI.

13.
Front Immunol ; 13: 847106, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35911725

RESUMO

Within the family Herpesviridae, sub-family ß-herpesvirinae, and genus Roseolovirus, there are only three human herpesviruses that have been described: HHV-6A, HHV-6B, and HHV-7. Initially, HHV-6A and HHV-6B were considered as two variants of the same virus (i.e., HHV6). Despite high overall genetic sequence identity (~90%), HHV-6A and HHV-6B are now recognized as two distinct viruses. Sequence divergence (e.g., >30%) in key coding regions and significant differences in physiological and biochemical profiles (e.g., use of different receptors for viral entry) underscore the conclusion that HHV-6A and HHV-6B are distinct viruses of the ß-herpesvirinae. Despite these viruses being implicated as causative agents in several nervous system disorders (e.g., multiple sclerosis, epilepsy, and chronic fatigue syndrome), the mechanisms of action and relative contributions of each virus to neurological dysfunction are unclear. Unresolved questions regarding differences in cell tropism, receptor use and binding affinity (i.e., CD46 versus CD134), host neuro-immunological responses, and relative virulence between HHV-6A versus HHV-6B prevent a complete characterization. Although it has been shown that both HHV-6A and HHV-6B can infect glia (and, recently, cerebellar Purkinje cells), cell tropism of HHV-6A versus HHV-6B for different nerve cell types remains vague. In this study, we show that both viruses can infect different nerve cell types (i.e., glia versus neurons) and different neurotransmitter phenotypes derived from differentiated human neural stem cells. As demonstrated by immunofluorescence, HHV-6A and HHV-6B productively infect VGluT1-containing cells (i.e., glutamatergic neurons) and dopamine-containing cells (i.e., dopaminergic neurons). However, neither virus appears to infect GAD67-containing cells (i.e., GABAergic neurons). As determined by qPCR, expression of immunological factors (e.g., cytokines) in cells infected with HHV-6A versus HHV6-B also differs. These data along with morphometric and image analyses of infected differentiated neural stem cell cultures indicate that while HHV-6B may have greater opportunity for transmission, HHV-6A induces more severe cytopathic effects (e.g., syncytia) at the same post-infection end points. Cumulatively, results suggest that HHV-6A is more virulent than HHV-6B in susceptible cells, while neither virus productively infects GABAergic cells. Consistency between these in vitro data and in vivo experiments would provide new insights into potential mechanisms for HHV6-induced epileptogenesis.


Assuntos
Herpesviridae , Herpesvirus Humano 6 , Células-Tronco Neurais , Efeito Citopatogênico Viral , Herpesvirus Humano 6/fisiologia , Humanos , Internalização do Vírus
14.
J Clin Invest ; 132(16)2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35852863

RESUMO

Chimeric antigen receptor (CAR) T cell therapies targeting single antigens have performed poorly in clinical trials for solid tumors due to heterogenous expression of tumor-associated antigens (TAAs), limited T cell persistence, and T cell exhaustion. Here, we aimed to identify optimal CARs against glypican 2 (GPC2) or CD276 (B7-H3), which were highly but heterogeneously expressed in neuroblastoma (NB), a lethal extracranial solid tumor of childhood. First, we examined CAR T cell expansion in the presence of targets by digital droplet PCR. Next, using pooled competitive optimization of CAR by cellular indexing of transcriptomes and epitopes by sequencing (CITE-Seq), termed P-COCC, we simultaneously analyzed protein and transcriptome expression of CAR T cells to identify high-activity CARs. Finally, we performed cytotoxicity assays to identify the most effective CAR against each target and combined the CARs into a bicistronic "OR" CAR (BiCisCAR). BiCisCAR T cells effectively eliminated tumor cells expressing GPC2 or CD276. Furthermore, the BiCisCAR T cells demonstrated prolonged persistence and resistance to exhaustion when compared with CARs targeting a single antigen. This study illustrated that targeting multiple TAAs with BiCisCAR may overcome heterogenous expression of target antigens in solid tumors and identified a potent, clinically relevant CAR against NB. Moreover, our multimodal approach integrating competitive expansion, P-COCC, and cytotoxicity assays is an effective strategy to identify potent CARs among a pool of candidates.


Assuntos
Neuroblastoma , Receptores de Antígenos Quiméricos , Antígenos de Neoplasias/genética , Antígenos B7 , Linhagem Celular Tumoral , Glipicanas/genética , Humanos , Imunoterapia Adotiva , Neuroblastoma/genética , Neuroblastoma/terapia , Receptores de Antígenos de Linfócitos T/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Nanomaterials (Basel) ; 11(12)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34947731

RESUMO

Hydrogen is considered to be a very efficient and clean fuel since it is a renewable and non-polluting gas with a high energy density; thus, it has drawn much attention as an alternative fuel, in order to alleviate the issue of global warming caused by the excess use of fossil fuels. In this work, a novel Cu/ZnS/COF composite photocatalyst with a core-shell structure was synthesized for photocatalytic hydrogen production via water splitting. The Cu/ZnS/COF microspheres formed by Cu/ZnS crystal aggregation were covered by a microporous thin-film COF with a porous network structure, where COF was also modified by the dual-effective redox sites of C=O and N=N. The photocatalytic hydrogen production results showed that the hydrogen production rate reached 278.4 µmol g-1 h-1, which may be attributed to its special structure, which has a large number of active sites, a more negative conduction band than the reduction of H+ to H2, and the ability to inhibit the recombination of electron-hole pairs. Finally, a possible mechanism was proposed to effectively explain the improved photocatalytic performance of the photocatalytic system. The present work provides a new concept, in order to construct a highly efficient hydrogen production catalyst and broaden the applications of ZnS-based materials.

16.
Ultrason Sonochem ; 80: 105824, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34763211

RESUMO

To harvest the photon energy, a sequenceof perovskite-type oxides of LaCoxFe1-xO3 (0 ≤x≤1) nanostructures with distinct 'Cobalt' doping at the position of B-site are successfully prepared via a simple ultrasonic approach as photocatalyst. The crystallinity, phase identification, microstructure, and morphology of perovskite nanocomposites were analyzed to better understand their physicochemical properties. The catalytic efficiency was assessedusing Congo Red (CR) dye by visible light irradiation for 30 min. Applying terephthalic acid as a probe molecule, the formation of hydroxyl radicals during the processes was investigated. The photocatalytic efficacy was measured by varying different Co/Fe stoichiometric molar ratios and noticed the order of sequence is 0.2 > 0.6 > 0.4 > 0.8 > 0.5 > 0 > 1 after 30 min of reaction time. Finally using LaCo0.2Fe0.8O3 nanostructures, cycling studies (n = 3) were performed to determine its photostability and reusability. The photocatalytic methodology proposed in this study was discussed extensively.

17.
Environ Technol ; : 1-11, 2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34057402

RESUMO

Polymers are highly promising materials for capturing carbon dioxide (CO2), a greenhouse gas. Hence in this work, we prepared phyllosilicate supported mesoporous polymer via reversible addition-fragmentation chain transfer (RAFT) polymerisation, which is the one among the controlled radical polymerisation. The mesoporous material anchored on dodecanethiol trithiocarbonate acts as a chain transfer agent (CTA) for the polymerisation of chloromethyl styrene and further conversion to quaternary ammonium compound which is effective to trap CO2 using tertiary amine. The synthesised porous phyllosilicate/polymer nanocomposites have been characterised by using various analytical tools. The CO2 sorption experiments were carried out by passing CO2 onto the synthesised porous phyllosilicate/polymer nanocomposites. The sorption kinetics was monitored by X-Ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR) spectra in the presence of carbonate were obtained by reaction of quaternary ammonium hydroxide and CO2. The phyllosilicate anchored macromolecular CTA (macro-CTA) and the surface-initiated polymer nanocomposites encompassed apparent surface areas of 94.5 and 26.8 m2 g-1, respectively. In addition, the total pore volumes calculated for the macro-CTA and polymer were found to be 0.27 and 0.095 cm3g-1, while the average pore sizes were 14.24 and 11.46 nm, respectively. The CO2 sorption capacity of the phyllosilicate/polymer nanocomposites, monitored at different temperatures, is the fastest for 25°C but slower for the sample treated at 50°C which may due to the dipole and quadrupole interaction.

18.
Angew Chem Int Ed Engl ; 60(28): 15225-15229, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33855792

RESUMO

Inhaled gene therapy poses a unique potential of curing chronic lung diseases, which are currently managed primarily by symptomatic treatments. However, it has been challenging to achieve therapeutically relevant gene transfer efficacy in the lung due to the presence of numerous biological delivery barriers. Here, we introduce a simple approach that overcomes both extracellular and cellular barriers to enhance gene transfer efficacy in the lung in vivo. We endowed tetra(piperazino)fullerene epoxide (TPFE)-based nanoparticles with non-adhesive surface polyethylene glycol (PEG) coatings, thereby enabling the nanoparticles to cross the airway mucus gel layer and avoid phagocytic uptake by alveolar macrophages. In parallel, we utilized a hypotonic vehicle to facilitate endocytic uptake of the PEGylated nanoparticles by lung parenchymal cells via the osmotically driven regulatory volume decrease (RVD) mechanism. We demonstrate that this two-pronged delivery strategy provides safe, wide-spread and high-level transgene expression in the lungs of both healthy mice and mice with chronic lung diseases characterized by reinforced delivery barriers.


Assuntos
Compostos de Epóxi/química , Fulerenos/química , Técnicas de Transferência de Genes , Pneumopatias/terapia , Nanopartículas/química , Doença Crônica , Humanos , Pneumopatias/metabolismo
19.
J Plast Reconstr Aesthet Surg ; 74(5): 1013-1021, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33446463

RESUMO

BACKGROUND: Chimeric anterolateral thigh free flaps (ALT) have been commonly used for head and neck defects, which require two epithelial lined surfaces. However, because of unpredictable vascular anatomy, it is a challenge to consistently elevate large chimeric flaps with multiple perforators based on the Lateral Circumflex Femoral Artery (LCFA). Here, we present our method to reliably harvest a chimeric flap from the ALT territory and investigate its long-term outcomes when used in the reconstruction of extensive head and neck defects. METHODS: A prospective review of practice consisting of 27 patients, between January 2011 and April 2019, with extensive through-and-through head and neck defects, which require dual paddle flaps underwent reconstruction with chimeric ALT harvested with a portion of distal vastus lateralis. The age of the patients ranged from 32 to 68 years (mean 53.2 years). RESULTS: Flap length ranged from 17 to 30 cm (mean, 25.6 cm). The mean flap area was 261.6 cm2 (range, from 225 to 340 cm2). The mean ischemia time was 162.9 min (range, from 59 to 269 min). At a mean follow-up time of 33.4 months (range, from 4 to 91 months), four patients died of cancer recurrence. For the other 23 patients, 4 required revision to achieve better cosmetic lip competence. All flaps survived with two recorded returns to theater for pedicle exploration associated with partial flap loss only. CONCLUSION: Harvesting the chimeric ALT with a portion of vastus lateralis distally negates the need for tenuous intramuscular perforator dissection. It is a reliable option for head and neck surgery, which require composite reconstruction. Using this technique produces a good functional cosmetic outcome. It also allows large defects to be reconstructed in a single sitting with free tissue transfer.


Assuntos
Retalhos de Tecido Biológico/transplante , Neoplasias de Cabeça e Pescoço/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Coxa da Perna/cirurgia , Adulto , Idoso , Estética , Retalhos de Tecido Biológico/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Coxa da Perna/irrigação sanguínea
20.
Expert Opin Drug Deliv ; 18(5): 595-606, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33218265

RESUMO

Introduction: Airway mucus gel layer serves as a key delivery barrier that limits the performance of inhaled drug delivery nanoparticles. Conventional nanoparticles are readily trapped by the airway mucus and rapidly cleared from the lung via mucus clearance mechanisms. These nanoparticles cannot distribute throughout the lung airways, long-reside in the lung and/or reach the airway epithelium. To address this challenge, strategies to enhance particle penetration through the airway mucus have been developed and proof-of-concept has been established using mucus model systems..Areas covered: In this review, we first overview the biochemical and biophysical characteristics that render the airway mucus a challenging delivery barrier. We then introduce strategies to improve particle penetration through the airway mucus. Specifically, we walk through two classes of approaches, including modification of physicochemical properties of nanoparticles and modulation of barrier properties of airway mucus.Expert opinion: State-of-the-art strategies to overcome the airway mucus barrier have been introduced and experimentally validated. However, data should be interpreted in the comprehensive context of therapeutic delivery from the site of administration to the final destination to determine clinically-relevant approaches. Further, safety should be carefully monitored, particularly when it comes to mucus-altering strategies that may perturb physiological functions of airway mucus.


Assuntos
Nanopartículas , Preparações Farmacêuticas , Sistemas de Liberação de Medicamentos , Humanos , Pulmão , Muco
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