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1.
Pak J Pharm Sci ; 34(3(Supplementary)): 1056-1062, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34602432

RESUMO

Recent studies on prevalence of urinary tract infection indicate that approximately one third population of the world has been suffering from this disease. The current study was designed to evaluate the antibacterial activity of aqueous-ethanolic extracts (30/70) of Tribulus terrestris (TT), Vaccinium macrocarpon (VM), Cuminum cyminum (CC), Rheum emodi (RE), Piper cubeba (PC) and their compound formulation "Crano-cure" against Escherichia coli, Klebsiella pneumonia, Staphylococcus saprophyticus and Proteus mirabilis through disc diffusion method and agar well methods compared with standard Ciprofloxacin. DPPH radical scavenging methods were applied for antioxidant activities and phytochemical analysis was also performed to detect the phytoconstituents. All the plants exhibited potent antibacterial strength while Crano-cure showed most potent results comparable with that of standard drug. The zone of inhibition produced by disk diffusion test was 26±0.34, 26±0.75, 26±0.00, 18±0.64, 22.5±0.52, 29±0.39, 32±0.00 mm and for agar well diffusion test 23±0.67, 22±0.46, 23±0.77, 20±0.00, 22±0.46, 24±0.52, 33±0.00 mm against Tribulus terrestris, Cuminum cyminum, Rheum emodi, Piper cubeba, Vaccinium macrocarpon, crano-cure and ciprofloxacin. Similarly, percentage inhibition for antioxidant potential was 78.74, 24.57, 58.75, 20.23, 88.88, 90.12 and 92.35 respectively. The tested plants exhibited remarkable antibacterial and antioxidant activities.

2.
J Plant Res ; 134(6): 1225-1242, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34505187

RESUMO

Despite its major role in global isoprene emission, information on the environmental control of isoprene emission from tropical trees has remained scarce. Thus, in this study, we examined the relationship between parameters of G-93 isoprene emission formula (CT1, CT2, and α), growth temperature and light intensity, photosynthesis (ɸ, Pmax), isoprene synthase (IspS) level, and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway metabolites using sunlit and shaded leaves of four tropical trees. The results showed that the temperature dependence of isoprene emission from shaded leaves did not differ significantly from sunlit leaves. In contrast, there was a lower saturation irradiance in shaded leaves than in sunlit leaves, the same as temperate plants. The photosynthesis rate of shaded leaves showed lower saturation irradiance, similar to the light dependence of isoprene emission. In most cases, the concentration of MEP pathway metabolites was of lower tendency in shaded leaves versus in sunlit leaves, whereas no significant difference was noted in IspS level between sunlit and shaded leaves. Correlation analysis between these parameters found that CT1 of the G-93 parameter was positively correlated with the concentration of DXP and DMADP, whereas CT2 correlated with the concentration of MEP and the average air temperature for the past 48 h. Similarly, α closely associated with the initial slope (ɸ) of photosynthesis rate, and the basal emission factor is also linked to the photon flux of past days. These results suggest that growth conditions may control the temperature dependence of isoprene emission from tropical trees via the changes in the profiles of MEP pathway metabolites, causing alteration in the parameters of the isoprene emission formula.

3.
Cornea ; 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34483268

RESUMO

PURPOSE: The aim of this study was to evaluate the influence of scleral lens on corneal curvature and corneal thickness in keratoconic patients. METHODS: Scheimpflug imaging was captured before lens insertion, immediately after removal at 6 hours, and, again, the next day morning. Anterior flat, steep, and maximal keratometry (Kflat, Ksteep, and Kmax, respectively) and pachymetry values were compared. RESULTS: Minimal corneal flattening was observed for all 3 curvature parameters immediately after lens removal but was not statistically significant. The average Kflat was 0.28 ± 0.31 (D) flatter (P = 0.37), Ksteep was 0.37 ± 0.09 (D) flatter (P = 0.11), and Kmax was 0.19 ± 0.24 (D) flatter (P = 0.53), which returned to baseline level after one night of lens removal. After 6 hours of a 16-mm scleral lens wear, central corneal pachymetry showed that a marginal thickening of 7.76 ± 3.00 µm (P = 0.06) was causing 1.77 ± 0.67% of corneal edema, which returned to baseline after one night of lens removal. There was no significant correlation noted between corneal flattening and change in corneal thickness (r = 0.09, P = 0.78) and between central corneal clearance and change in corneal curvature (r = -0.23, P = 0.51). CONCLUSIONS: Minimal transient alteration in the anterior corneal curvature and corneal thickness was observed after 6 hours of scleral lens wear. These temporary changes regressed to baseline after overnight discontinuation of the lens.

4.
Eye Contact Lens ; 47(10): 578-580, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34369409

RESUMO

ABSTRACT: This case report details the efficacy of in-clinic customized scleral lens trial with self-preserved antibiotic eye drop in the liquid reservoir, in promoting fast healing of persistent corneal epithelial defect (PED). A 57-year-old man with a PED following injury, not responding to conventional treatment, underwent an in-clinic therapeutic trial of prosthetic replacement of ocular surface ecosystem device, to promote epithelial healing. After device wear with antibiotic eye drop in the liquid reservoir for 8 hrs during the day on five consecutive days and pressure patching at night with antibiotic eye ointment, there was complete resolution of the PED. Prosthetic replacement of ocular surface ecosystem scleral lenses are an effective treatment modality for PED. In-clinic daytime lens wear with night time pressure patching is a cost-effective option. Expert supervision avoids patient learning curve issues. Corneal re-epithelization happens because of the moisture and protection of the fragile healing epithelium afforded by these high DK lenses.


Assuntos
Doenças da Córnea , Ecossistema , Doenças da Córnea/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Esclera , Acuidade Visual
5.
Sensors (Basel) ; 21(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34372186

RESUMO

We propose a physical activity recognition and monitoring framework based on wearable sensors during maternity. A physical activity can either create or prevent health issues during a given stage of pregnancy depending on its intensity. Thus, it becomes very important to provide continuous feedback by recognizing a physical activity and its intensity. However, such continuous monitoring is very challenging during the whole period of maternity. In addition, maintaining a record of each physical activity, and the time for which it was performed, is also a non-trivial task. We aim at such problems by first recognizing a physical activity via the data of wearable sensors that are put on various parts of body. We avoid the use of smartphones for such task due to the inconvenience caused by wearing it for activities such as "eating". In our proposed framework, a module worn on body consists of three sensors: a 3-axis accelerometer, 3-axis gyroscope, and temperature sensor. The time-series data from these sensors are sent to a Raspberry-PI via Bluetooth Low Energy (BLE). Various statistical measures (features) of this data are then calculated and represented in features vectors. These feature vectors are then used to train a supervised machine learning algorithm called classifier for the recognition of physical activity from the sensors data. Based on such recognition, the proposed framework sends a message to the care-taker in case of unfavorable situation. We evaluated a number of well-known classifiers on various features developed from overlapped and non-overlapped window size of time-series data. Our novel dataset consists of 10 physical activities performed by 61 subjects at various stages of maternity. On the current dataset, we achieve the highest recognition rate of 89% which is encouraging for a monitoring and feedback system.


Assuntos
Dispositivos Eletrônicos Vestíveis , Algoritmos , Exercício Físico , Feminino , Humanos , Gravidez , Reconhecimento Psicológico , Tempo
6.
Environ Monit Assess ; 193(9): 575, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392406

RESUMO

Motor vehicles operating on the road are a significant source of Particulate Matter (PM) emissions depending on the fuels used in the vehicles. Gasoline and Diesel vehicles are directly responsible for the tailpipe PM emissions (specifically PM2.5: particles ≤ 2.5 µm), known as primary PM2.5 emissions. The other major direct emissions from the vehicles, which include volatile organic compounds (VOCs), and nitrogen oxides (NOx) contribute to the formation of secondary organic PM, also known as secondary organic aerosols (SOA), through some inter-related chemical reactions. The SOAs are highly toxic and contribute to a portion of total PM emissions. In this research, emission scenarios of both primary PM2.5 and SOA for a car-dependent expanding Australian city (Adelaide) were analyzed. The variability of traffic characteristics on road was considered and conducted a probabilistic emissions inventory for tailpipe primary PM2.5 and precursors, while statistical analysis of the probable chemical conversion ratios was considered for the SOA inventory. It was found that the tailpipe emissions from the vehicles were higher than the air quality standard, while the SOA contribution from the vehicles was not significantly high but contributed to the increase of total PM concentration. The analysis of the chemical transformation of SOA precursors justified the importance of conducting more detailed emissions modelling for sustainable urban air quality planning.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Austrália , Monitoramento Ambiental , Gasolina/análise , Material Particulado/análise , Emissões de Veículos/análise
7.
Appl Environ Microbiol ; 87(18): e0091521, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34260305

RESUMO

Rice is an important source of food for more than half of the world's population. Bacterial panicle blight (BPB) is a disease of rice characterized by grain discoloration or sheath rot caused mainly by Burkholderia glumae. B. glumae synthesizes toxoflavin, an essential virulence factor that is required for symptoms of the disease. The products of the tox operons, ToxABCDE and ToxFGHI, are responsible for the synthesis and the proton motive force (PMF)-dependent secretion of toxoflavin, respectively. The DedA family is a highly conserved membrane protein family found in most bacterial genomes that likely function as membrane transporters. Our previous work has demonstrated that absence of certain DedA family members results in pleiotropic effects, impacting multiple pathways that are energized by PMF. We have demonstrated that a member of the DedA family from Burkholderia thailandensis, named DbcA, is required for the extreme polymyxin resistance observed in this organism. B. glumae encodes a homolog of DbcA with 73% amino acid identity to Burkholderia thailandensis DbcA. Here, we created and characterized a B. glumae ΔdbcA strain. In addition to polymyxin sensitivity, the B. glumae ΔdbcA strain is compromised for virulence in several BPB infection models and secretes only low amounts of toxoflavin (∼15% of wild-type levels). Changes in membrane potential in the B. glumae ΔdbcA strain were reproduced in the wild-type strain by the addition of subinhibitory concentrations of sodium bicarbonate, previously demonstrated to cause disruption of PMF. Sodium bicarbonate inhibited B. glumae virulence in rice, suggesting a possible non-toxic chemical intervention for bacterial panicle blight. IMPORTANCE Bacterial panicle blight (BPB) is a disease of rice characterized by grain discoloration or sheath rot caused mainly by Burkholderia glumae. The DedA family is a highly conserved membrane protein family found in most bacterial genomes that likely function as membrane transporters. Here, we constructed a B. glumae mutant with a deletion in a DedA family member named dbcA and report a loss of virulence in models of BPB. Physiological analysis of the mutant shows that the proton motive force is disrupted, leading to reduction of secretion of the essential virulence factor toxoflavin. The mutant phenotypes are reproduced in the virulent wild-type strain without an effect on growth using sodium bicarbonate, a nontoxic buffer that has been reported to disrupt the PMF. The results presented here suggest that bicarbonate may be an effective antivirulence agent capable of controlling BPB without imposing an undue burden on the environment.


Assuntos
Burkholderia , Oryza/microbiologia , Doenças das Plantas/microbiologia , Força Próton-Motriz , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Burkholderia/efeitos dos fármacos , Burkholderia/genética , Burkholderia/metabolismo , Burkholderia/patogenicidade , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Cebolas/microbiologia , Pirimidinonas/metabolismo , Bicarbonato de Sódio/farmacologia , Triazinas/metabolismo , Virulência , Fatores de Virulência/metabolismo
8.
PLoS One ; 16(7): e0254318, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34314420

RESUMO

Screening for drought tolerance requires precise techniques like phonemics, which is an emerging science aimed at non-destructive methods allowing large-scale screening of genotypes. Large-scale screening complements genomic efforts to identify genes relevant for crop improvement. Thirty maize inbred lines from various sources (exotic and indigenous) maintained at Dryland Agriculture Research Station were used in the current study. In the automated plant transport and imaging systems (LemnaTec Scanalyzer system for large plants), top and side view images were taken of the VIS (visible) and NIR (near infrared) range of the light spectrum to capture phenes. All images were obtained with a thermal imager. All sensors were used to collect images one day after shifting the pots from the greenhouse for 11 days. Image processing was done using pre-processing, segmentation and flowered by features' extraction. Different surrogate traits such as pixel area, plant aspect ratio, convex hull ratio and calliper length were estimated. A strong association was found between canopy temperature and above ground biomass under stress conditions. Promising lines in different surrogates will be utilized in breeding programmes to develop mapping populations for traits of interest related to drought resilience, in terms of improved tissue water status and mapping of genes/QTLs for drought traits.

9.
Front Immunol ; 12: 687711, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34140956

RESUMO

Leukocyte recruitment to the site of injury is a crucial event in the regulation of an inflammatory response. Tight regulation of interactions between the endothelium and circulating leukocytes is necessary to ensure a protective response to injury does not result in inflammatory disease. Rising interest in the broad immunoregulatory roles displayed by members of the glycan-binding galectin family suggests that these proteins could be an attractive target for therapeutic intervention, since their expression is significantly altered in disease. The focus of this review is to summarize current knowledge on the role of galectins in leukocyte trafficking during inflammation and the clinical approaches being taken to target these interactions for treatment of inflammatory disease.

10.
Sensors (Basel) ; 21(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064750

RESUMO

Autistic people face many challenges in various aspects of daily life such as social skills, repetitive behaviors, speech, and verbal communication. They feel hesitant to talk with others. The signs of autism vary from one individual to another, with a range from mild to severe. Autistic children use fewer communicative gestures compared with typically developing children (TD). With time, the parents may learn their gestures and understand what is occurring in their child's mind. However, it is difficult for other people to understand their gestures. In this paper, we propose a wearable-sensors-based platform to recognize autistic gestures using various classification techniques. The proposed system defines, monitors, and classifies the gestures of the individuals. We propose using wearable sensors that transmit their data using a Bluetooth interface to a data acquisition and classification server. A dataset of 24 gestures is created by 10 autistic children performing each gesture about 10 times. Time- and frequency-domain features are extracted from the sensors' data, which are classified using k-nearest neighbor (KNN), decision tree, neural network, and random forest models. The main objective of this work is to develop a wearable-sensor-based IoT platform for gesture recognition in children with autism spectrum disorder (ASD). We achieve an accuracy of about 91% with most of the classifiers using dataset cross-validation and leave-one-person-out cross-validation.


Assuntos
Transtorno do Espectro Autista , Dispositivos Eletrônicos Vestíveis , Algoritmos , Transtorno do Espectro Autista/diagnóstico , Criança , Gestos , Humanos , Aprendizado de Máquina
11.
GM Crops Food ; : 1-22, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33938377

RESUMO

In vitro recalcitrance of wheat to regeneration is the major bottleneck for its improvement through callus-based genetic transformation. Nanotechnology is one of the most dynamic areas of research, which can transform agriculture and biotechnology to ensure food security on sustainable basis. Present study was designed to investigate effects of CuSO4, AgNO3 and their nanoparticles on tissue culture responses of mature embryo culture of wheat genotypes (AS-2002 and Wafaq-2001). Initially, MS-based callus induction and regeneration medium were optimized for both genotypes using various concentrations of auxin (2,4-D, IAA) and cytokinins (BAP, kinetin). The genotypes differed for embryogenic callus induction and regeneration potential. Genotype AS-2002 yielded maximum embryogenic calli in response to 3.0 mg/l 2,4-D, whereas Wafaq-2001 offered the highest embryogenic calli against 3.5 mg/l 2,4-D supplemented in the induction medium. Genotype AS-2002 showed maximum regeneration (59.33%) in response to regeneration protocol comprising 0.5 mg/l IAA, 0.3 mg/l BAP and 1.0 mg/l Kin, while Wafaq-2001 performed best in response to 0.5 mg/l IAA, 0.3 mg/l BAP and 1.5 mg/l Kin with 55.33% regeneration efficiency. The same optimized basal induction and regeneration medium for both genotypes were further used to study effects of CuSO4, AgNO3 and their nano-particles employing independent experiments. The optimized induction medium fortified with various concentrations of CuSO4 or CuNPs confirmed significant effects on frequency of embryogenic callus. Addition of either 0.020 mg/l or 0.025 mg/l CuSO4, or 0.015 mg/l CNPs showed comparable results for embryogenic callus induction and were statistically at par with embryogenic callus induction of 74.00%, 75.67% and 76.83%, respectively. Significantly higher regeneration was achieved from MS-based regeneration medium supplemented with 0.015 mg/l or 0.020 mg/l CuNPs than standard 0.025 mg/l CuSO4. In another study, the basal induction and regeneration medium were fortified with AgNO3 or AgNPs ranging from 1 to 7 mg/l along with basal regeneration media devoid of AgNO3 or AgNPs (control). The maximum embryogenic calli were witnessed from medium fortified with 3.0 mg/l or 4.0 mg/l AgNPs compared with control and rest of the treatments. The standardized regeneration medium fortified with 5.0 mg/l AgNO3 or 3.0 mg/l AgNPs showed pronounced effect on regeneration of wheat genotypes and offered maximum regeneration compared with control. The individual and combined effect of Cu and Ag nanoparticles along with control (basal regeneration media of each genotype) was also tested. Surprisingly, co-application of metallic NPs showed a significant increase in embryogenic callus formation of genotypes. Induction medium supplemented with 0.015 mg/l CuNPs + 4.0 mg/l AgNPs or 0.020 mg/l CuNPs + 2.0 mg/l AgNPs showed splendid results compared to control and other combination of Cu and Ag nanoparticles. The maximum regeneration was achieved by co-application of 0.015 mg/l CuNP and 4.0 mg/l AgNPs with 21% increment of regeneration over control. It is revealed that CuNPs and AgNPs are potential candidate to augment somatic embryogenesis and regeneration of mature embryo explants of wheat.

12.
J Clin Pathol ; 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33789921

RESUMO

AIMS: Despite clinical evidence of liver involvement in patients with coeliac disease (CeD), there is a lack of a method to prove this association. METHODS: Of 146 treatment-naive patients with CeD, 26 had liver dysfunction. Liver biopsies and corresponding small intestinal biopsies were obtained from these 26 patients. Multicolour immunohistochemical and immunofluorescence confocal microscopic studies were performed on paraffin-embedded tissue to detect the IgA/anti-TG2 deposits. Follow-up liver biopsies were taken after a gluten-free diet. RESULTS: Twenty-six out of the 146 patients (17.8%) with suspected coeliac-associated liver disease on histological examination revealed irregular sinusoidal dilatation in 15 (57.6%), steatohepatitis in 4 (15.3%), non-specific chronic hepatitis in 3 (11.5%), autoimmune hepatitis in 2 (7.6%) biopsies, including cirrhosis in one of them, irregular perisinusoidal fibrosis and changes of non-cirrhotic portal fibrosis in one biopsy each (3.8%). IgA/anti-tTG deposits were observed in 22 (84.6%) liver biopsies by dual immunohistochemistry technique, and in 24 (92.3%) by confocal immunofluorescence technique and in all corresponding duodenal biopsies (100%). Overall, IgA/anti-tTG deposits showed 100% sensitivity, 77% specificity and 85% positive predictive value for establishing an association of extraintestinal pathology and CeD using archived tissues. Follow-up liver biopsies could be obtained in five patients; four of them showed not only resolution of the histological lesions but disappearance of IgA/anti-tTG co-localisation. CONCLUSIONS: Data of the present study adds to the body of evidence that liver lesions in patients with CeD are disease related and may have been caused by a similar pathogenic mechanism that causes intestinal changes.

13.
Clin Exp Optom ; 104(7): 760-766, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33689628

RESUMO

Clinical relevance: It is important to investigate the effect of modulus of silicone hydrogel contact lens on meibomian glands. Evaluating meibomian gland health and function in follow-up appointments should be considered, with the option of changing lens modulus.Background: To evaluate and compare the effect of modulus of elasticity of silicone hydrogel contact lenses on morphological and functional parameters of the meibomian glands.Methods: A prospective study was conducted on soft silicone hydrogel contact lens wearers of different modulus of elasticity and age and gender-matched controls. Morphological and functional parameters were assessed along with standard patient evaluation of the eye dryness questionnaire.Results: A statistically significant difference was noted in meibomian gland loss in the upper lid (percent) between the low modulus (18.23 ± 6.63) and high modulus group (27.40 ± 10.21) (p < 0.001) and between high modulus (27.40 ± 10.21) and non-contact lens wearers (19.57 ± 7.65) (p = 0.001). The current study reported significantly higher total meiboscore grading in the high modulus group 3 (2-3) compared to the low modulus 2(2-3) (p = 0.007) and non-contact lens wearing groups 2 (2-3) (p = 0.012). Meibum quality was significantly compromised in the high modulus group 1 (0-1) compared to the low modulus 0 (0-0.75) group (p = 0.01). Standard patient evaluation of the eye dryness questionnaire was found to be significantly higher (p = 0.01) in high modulus 4 (2-8) compared to low modulus wearers 2 (2-4). A significant difference was noted (p < 0.001) in corneal staining grading only between high modulus 0 (0-1) and non-contact lens wearers 0 (0-0) group. A positive correlation was noted in the low modulus group between total meiboscore and meibomian gland expressibility (Rs = +0.69, p < 0.001) and also noted between standard patient evaluation of the eye dryness questionnaire scoring and meibomian gland expressibility (Rs = +0.45, p = 0.012) in the high modulus group.Conclusion: Higher modulus of elasticity of silicone hydrogel contact lens may influence meibomian gland morphology and function over a period of contact lens wear.


Assuntos
Lentes de Contato Hidrofílicas , Glândulas Tarsais , Módulo de Elasticidade , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Hidrogéis , Estudos Prospectivos , Silicones
14.
Artigo em Inglês | MEDLINE | ID: mdl-33595275

RESUMO

Recent studies have demonstrated the high efficiency through which nanostructured core-shell WO3/TiO2 (WT) heterojunctions can photocatalytically degrade model organic pollutants (stearic acid, QE ≈ 18% @ λ = 365 nm), and as such, has varied potential environmental and antimicrobial applications. The key motivation herein is to connect theoretical calculations of charge transport phenomena, with experimental measures of charge carrier behavior using transient absorption spectroscopy (TAS), to develop a fundamental understanding of how such WT heterojunctions achieve high photocatalytic efficiency (in comparison to standalone WO3 and TiO2 photocatalysts). This work reveals an order of magnitude enhancement in electron and hole recombination lifetimes, respectively located in the TiO2 and WO3 sides, when an optimally designed WT heterojunction photocatalyst operates under UV excitation. This observation is further supported by our computationally captured details of conduction band and valence band processes, identified as (i) dominant electron transfer from WO3 to TiO2 via the diffusion of excess electrons; and (ii) dominant hole transfer from TiO2 to WO3 via thermionic emission over the valence band edge. Simultaneously, our combined theoretical and experimental study offers a time-resolved understanding of what occurs on the micro- to milliseconds (µs-ms) time scale in this archetypical photocatalytic heterojunction. At the microsecond time scale, a portion of the accumulated holes in WO3 contribute to the depopulation of W5+ polaronic states, whereas the remaining accumulated holes in WO3 are separated from adjacent electrons in TiO2 up to 3 ms after photoexcitation. The presence of these exceptionally long-lived photogenerated carriers, dynamically separated by the WT heterojunction, is the origin of the superior photocatalytic efficiency displayed by this system (in the degradation of stearic acid). Consequently, our combined computational and experimental approach delivers a robust understanding of the direction of charge separation along with critical time-resolved insights into the evolution of charge transport phenomena in this model heterojunction photocatalyst.

15.
Br J Pharmacol ; 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33595097

RESUMO

BACKGROUND AND PURPOSE: Recent biochemical and pharmacological studies have reported that in several tissues and cell types, microsomal PGE2 synthase (mPGES) and PPAR-γ expression are modulated by a variety of inflammatory factors and stimuli. Considering that very little is known about the biological effects promoted by IL-17 in the context of mPGES-1/PPAR-γ modulation, we sought to investigate the contribution of this unique cytokine on this integrated pathway during the onset of inflammation. EXPERIMENTAL APPROACH: We evaluated effects of PF 9184 (mPGES-1 inhibitor) and troglitazone (PPAR-γ agonist) in vitro, using the mouse macrophage cell line J774A.1. In vivo, the dorsal air pouch model in CD1 mice was used, and inflammatory infiltrates were analysed by flow cytometry. Locally produced cyto-chemokines and PGs were assessed using elisa assays. Western blots were also employed to determine the activity of various enzymes involved in downstream signalling pathways. KEY RESULTS: PF 9184 and troglitazone, in a time- and dose-dependent manner, modulated leukocyte infiltration, myeloperoxidase activity, and the expression of COX-2/mPGES-1, NF-кB/IкB-α, and mPTGDS-1/PPAR-γ, induced by IL-17. Moreover, both PF 9184 and troglitazone modulated PG (PGE2 , PGD2 , and PGJ2 ) production, the expression of different pro-inflammatory cyto-chemokines, and the recruitment of inflammatory monocytes, in response to IL-17. CONCLUSIONS AND IMPLICATIONS: Our data suggest that IL-17 may constitute a specific modulator of inflammatory monocytes during later phases of the inflammatory response. The results of this study show, for the first time, that the IL-17/mPGES-1/PPAR-γ pathway could represent a potential therapeutic target for inflammatory-based and immune-mediated diseases.

16.
Molecules ; 25(24)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33353211

RESUMO

Several natural-based compounds and products are reported to possess anti-inflammatory and immunomodulatory activity both in vitro and in vivo. The primary target for these activities is the inhibition of eicosanoid-generating enzymes, including phospholipase A2, cyclooxygenases (COXs), and lipoxygenases, leading to reduced prostanoids and leukotrienes. Other mechanisms include modulation of protein kinases and activation of transcriptases. However, only a limited number of studies and reviews highlight the potential modulation of the coupling enzymatic pathway COX-2/mPGES-1 and Th17/Treg circulating cells. Here, we provide a brief overview of natural products/compounds, currently included in the Italian list of botanicals and the BELFRIT, in different fields of interest such as inflammation and immunity. In this context, we focus our opinion on novel therapeutic targets such as COX-2/mPGES-1 coupling enzymes and Th17/Treg circulating repertoire. This paper is dedicated to the scientific career of Professor Nicola Mascolo for his profound dedication to the study of natural compounds.


Assuntos
Anti-Inflamatórios/farmacologia , Doenças Autoimunes/tratamento farmacológico , Produtos Biológicos/farmacologia , Ciclo-Oxigenase 1/metabolismo , Inflamação/tratamento farmacológico , Anti-Inflamatórios/química , Doenças Autoimunes/metabolismo , Produtos Biológicos/química , Terapias Complementares , Ciclo-Oxigenase 2/metabolismo , Humanos , Inflamação/metabolismo , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Células Th17
17.
Phys Rev E ; 102(4-1): 043201, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33212605

RESUMO

This work investigates the time-dependent physics of multipactor discharge on a single dielectric surface with a transverse rf electric field of two carrier frequencies using a multiparticle Monte Carlo simulation model with adaptive time steps. The effects of the relative strength and phase, and the frequency separation between the two carriers are studied. Closed Lissajous curves are obtained to describe the relationship between the rf electric field parallel to the surface and the normal surface charging field in the ac saturation state. It is found that two-frequency operation can reduce the multipactor strength compared to single-frequency operation with the same total rf power, though the effect of the frequency separation is not prominent on multipactor susceptibility. Formation of beat waves is observed in the temporal profiles of the normal electric field due to surface charging with a noninteger frequency ratio between the two carrier modes. Phase space evolution of multipactor electrons is examined, revealing a periodic bunching and debunching of electrons in the surface normal direction, but a gradual debunching effect in the direction tangential to the dielectric surface. Migration of the multipactor trajectory is also demonstrated for different configurations of the two-frequency rf fields.

18.
Front Vet Sci ; 7: 505, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33102539

RESUMO

Cannabidiol (CBD)-rich hemp extract use is increasing in veterinary medicine with little examination of serum cannabinoids. Many products contain small amounts of Δ9-tetrahydrocannabinol (THC), and precursor carboxylic acid forms of CBD and THC known as cannabidiolic acid (CBDA) and tetrahydrocannabinolic acid (THCA). Examination of the pharmacokinetics of CBD, CBDA, THC, and THCA on three oral forms of CBD-rich hemp extract that contained near equal amounts of CBD and CBDA, and minor amounts (<0.3% by weight) of THC and THCA in dogs was performed. In addition, we assess the metabolized psychoactive component of THC, 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC) and CBD metabolites 7-hydroxycannabidiol (7-OH-CBD) and 7-nor-7-carboxycannabidiol (7-COOH-CBD) to better understand the pharmacokinetic differences between three formulations regarding THC and CBD, and their metabolism. Six purpose-bred female beagles were utilized for study purposes, each having an initial 7-point, 24-h pharmacokinetic study performed using a dose of 2 mg/kg body weight of CBD/CBDA (~1 mg/kg CBD and ~1 mg/kg CBDA). Dogs were then dosed every 12 h for 2 weeks and had further serum analyses at weeks 1 and 2, 6 h after the morning dose to assess serum cannabinoids. Serum was analyzed for each cannabinoid or cannabinoid metabolite using liquid chromatography and tandem mass spectroscopy (LC-MS/MS). Regardless of the form provided (1, 2, or 3) the 24-h pharmacokinetics for CBD, CBDA, and THCA were similar, with only Form 2 generating enough data above the lower limit of quantitation to assess pharmacokinetics of THC. CBDA and THCA concentrations were 2- to 3-fold higher than CBD and THC concentrations, respectively. The 1- and 2-week steady-state concentrations were not significantly different between the two oils or the soft chew forms. CBDA concentrations were statistically higher with Form 2 than the other forms, showing superior absorption/retention of CBDA. Furthermore, Form 1 showed less THCA retention than either the soft chew Form 3 or Form 2 at weeks 1 and 2. THC was below the quantitation limit of the assay for nearly all samples. Overall, these findings suggest CBDA and THCA are absorbed or eliminated differently than CBD or THC, respectively, and that a partial lecithin base provides superior absorption and/or retention of CBDA and THCA.

19.
Int J Mol Sci ; 21(19)2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32993051

RESUMO

Cytokines and extracellular vesicles are two methods of initiating and maintaining cellular crosstalk. The role of cytokines in the initiation, progression, and resolution of inflammation has been well studied and more so, their pathophysiological role in the development of autoimmune disease. In recent years, the impact of extracellular vesicles on the progression of autoimmunity has become more widely appreciated. In this review, we discuss the mechanisms that allow extracellular vesicles of various sources to modulate cytokine production, and release, and how extracellular vesicles might be involved in the direct delivery and modulation of cytokine levels. Moreover, we explore what challenges are faced by current therapies and the promising future for extracellular vesicles as therapeutic agents in conditions driven by immune dysregulation.


Assuntos
Doenças Autoimunes/imunologia , Autoimunidade , Citocinas/imunologia , Vesículas Extracelulares/imunologia , Animais , Doenças Autoimunes/patologia , Vesículas Extracelulares/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia
20.
Phys Chem Chem Phys ; 22(35): 19631-19642, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32869781

RESUMO

Semiconductor-liquid interfaces are essential to the operation of many energy devices. Crucially, the operational characteristics of such devices are dependent upon both the flat band potential and doping concentration present in their solid-state semiconducting region. Traditionally, capacitive "linear" Mott-Schottky plots have often been utilized to extract these two parameters. However, significant concentrations of surface states within semiconductor-liquid junctions can give rise to strong non-linearities that prevent an effective linearity-based analysis. In this work, we detail a theoretical approach for estimating both the doping concentration and flat band potential from the capacitive characteristics of semiconductor-liquid junctions heavily impacted upon by surface states. Our theoretical approach is applied to CuGaS2 immersed in an aqueous electrolyte, for which excellent convergent values of the doping concentration and flat band potential are obtained across a wide range of impedance measurement frequencies. The results suggest a marked improvement over a linearity-based approach that could assist the analysis of many types of semiconductor-liquid junctions subject to high concentrations of surface states.

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