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1.
Nature ; 603(7900): 271-275, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35038718

RESUMO

In oxidation reactions catalysed by supported metal nanoparticles with oxygen as the terminal oxidant, the rate of the oxygen reduction can be a limiting factor. This is exemplified by the oxidative dehydrogenation of alcohols, an important class of reactions with modern commercial applications1-3. Supported gold nanoparticles are highly active for the dehydrogenation of the alcohol to an aldehyde4 but are less effective for oxygen reduction5,6. By contrast, supported palladium nanoparticles offer high efficacy for oxygen reduction5,6. This imbalance can be overcome by alloying gold with palladium, which gives enhanced activity to both reactions7,8,9; however, the electrochemical potential of the alloy is a compromise between that of the two metals, meaning that although the oxygen reduction can be improved in the alloy, the dehydrogenation activity is often limited. Here we show that by separating the gold and palladium components in bimetallic carbon-supported catalysts, we can almost double the reaction rate compared with that achieved with the corresponding alloy catalyst. We demonstrate this using physical mixtures of carbon-supported monometallic gold and palladium catalysts and a bimetallic catalyst comprising separated gold and palladium regions. Furthermore, we demonstrate electrochemically that this enhancement is attributable to the coupling of separate redox processes occurring at isolated gold and palladium sites. The discovery of this catalytic effect-a cooperative redox enhancement-offers an approach to the design of multicomponent heterogeneous catalysts.


Assuntos
Ouro , Nanopartículas Metálicas , Álcoois , Ligas , Carbono , Catálise , Oxirredução , Oxigênio , Paládio
2.
Stroke ; 55(5): 1428-1437, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38648283

RESUMO

BACKGROUND: Intracranial aneurysms (IAs) remain a challenging neurological diagnosis associated with significant morbidity and mortality. There is a plethora of microsurgical and endovascular techniques for the treatment of both ruptured and unruptured aneurysms. There is no definitive consensus as to the best treatment option for this cerebrovascular pathology. The Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts discussed best practices and the most promising approaches to improve the management of brain aneurysms. METHODS: A group of experts from academia, industry, and federal regulators convened to discuss updated clinical trials, scientific research on preclinical system models, management options, screening and monitoring, and promising novel device technologies, aiming to improve the outcomes of patients with IA. RESULTS: Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts suggested the incorporation of artificial intelligence to capture sequential aneurysm growth, identify predictors of rupture, and predict the risk of rupture to guide treatment options. The consensus strongly recommended nationwide systemic data collection of unruptured IA radiographic images for the analysis and development of machine learning algorithms for rupture risk. The consensus supported centers of excellence for preclinical multicenter trials in areas such as genetics, cellular composition, and radiogenomics. Optical coherence tomography and magnetic resonance imaging contrast-enhanced 3T vessel wall imaging are promising technologies; however, more data are needed to define their role in IA management. Ruptured aneurysms are best managed at large volume centers, which should include comprehensive patient management with expertise in microsurgery, endovascular surgery, neurology, and neurocritical care. CONCLUSIONS: Clinical and preclinical studies and scientific research on IA should engage high-volume centers and be conducted in multicenter collaborative efforts. The future of IA diagnosis and monitoring could be enhanced by the incorporation of artificial intelligence and national radiographic and biologic registries. A collaborative effort between academic centers, government regulators, and the device industry is paramount for the adequate management of IA and the advancement of the field.


Assuntos
Aneurisma Intracraniano , Humanos , Aneurisma Roto/terapia , Aneurisma Roto/diagnóstico por imagem , Consenso , Procedimentos Endovasculares/métodos , Procedimentos Endovasculares/normas , Aneurisma Intracraniano/terapia , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/diagnóstico
3.
Small ; 20(31): e2310013, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38477696

RESUMO

Nanomaterials like graphene and transition metal dichalcogenides are being explored for developing artificial photosensory synapses with low-power optical plasticity and high retention time for practical nervous system implementation. However, few studies are conducted on Tellurium (Te)-based nanomaterials due to their direct and small bandgaps. This paper reports the superior photo-synaptic properties of covalently bonded Tellurium sulfur oxide (TeSOx) and Tellurium selenium oxide (TeSeOx)nanomaterials, which are fabricated by incorporating S and Se atoms on the surface of Te multiropes using vapor deposition. Unlike pure Te multiropes, the TeSOx and TeSeOx multiropes exhibit controllable temporal dynamics under optical stimulation. For example, the TeSOx multirope-based transistor displays a photosensory synaptic response to UV light (λ = 365 nm). Furthermore, the TeSeOx multirope-based transistor exhibits photosensory synaptic responses to UV-vis light (λ = 365, 565, and 660 nm), reliable electrical performance, and a combination of both photodetector and optical artificial synaptic properties with a maximum responsivity of 1500 AW-1 to 365 nm UV light. This result is among the highest reported for Te-heterostructure-based devices, enabling optical artificial synaptic applications with low voltage spikes (1 V) and low light intensity (21 µW cm-2), potentially useful for optical neuromorphic computing.

4.
BMC Microbiol ; 24(1): 176, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778276

RESUMO

BACKGROUND: Mangrove sediment microbes are increasingly attracting scientific attention due to their demonstrated capacity for diverse bioremediation activities, encompassing a wide range of environmental contaminants. MATERIALS AND METHODS: The microbial communities of five Avicennia marina mangrove sediment samples collected from Al Rayyis White Head, Red Sea (KSA), were characterized using Illumina amplicon sequencing of the 16S rRNA genes. RESULTS: Our study investigated the microbial composition and potential for organohalide bioremediation in five mangrove sediments from the Red Sea. While Proteobacteria dominated four microbiomes, Bacteroidetes dominated the fifth. Given the environmental concerns surrounding organohalides, their bioremediation is crucial. Encouragingly, we identified phylogenetically diverse organohalide-respiring bacteria (OHRB) across all samples, including Dehalogenimonas, Dehalococcoides, Anaeromyxobacter, Desulfuromonas, Geobacter, Desulfomonile, Desulfovibrio, Shewanella and Desulfitobacterium. These bacteria are known for their ability to dechlorinate organohalides through reductive dehalogenation. PICRUSt analysis further supported this potential, predicting the presence of functional biomarkers for organohalide respiration (OHR), including reductive dehalogenases targeting tetrachloroethene (PCE) and 3-chloro-4-hydroxyphenylacetate in most sediments. Enrichment cultures studies confirmed this prediction, demonstrating PCE dechlorination by the resident microbial community. PICRUSt also revealed a dominance of anaerobic metabolic processes, suggesting the microbiome's adaptation to the oxygen-limited environment of the sediments. CONCLUSION: This study provided insights into the bacterial community composition of five mangrove sediments from the Red Sea. Notably, diverse OHRB were detected across all samples, which possess the metabolic potential for organohalide bioremediation through reductive dehalogenation pathways. Furthermore, PICRUSt analysis predicted the presence of functional biomarkers for OHR in most sediments, suggesting potential intrinsic OHR activity by the enclosed microbial community.


Assuntos
Bactérias , Biodegradação Ambiental , Sedimentos Geológicos , Microbiota , Filogenia , RNA Ribossômico 16S , Sedimentos Geológicos/microbiologia , RNA Ribossômico 16S/genética , Microbiota/genética , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Bactérias/isolamento & purificação , Oceano Índico , Metagenômica , DNA Bacteriano/genética , Áreas Alagadas , Metagenoma
5.
BMC Womens Health ; 24(1): 453, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39135014

RESUMO

BACKGROUND: The World Health Organization reports that depression affects more than 280 million people globally. Women are approximately 50% more likely to experience depression compared to men. Depression during pregnancy leads to deterioration of the mother's and the fetus's health. We aim to explore women's perceptions and attitudes toward using antidepressants and to identify the factors that influence decision-making regarding antidepressant use. METHOD: A cross-sectional survey, employing a convenience sampling method, was conducted on a university campus in Riyadh, Saudi Arabia. The survey was developed by the investigators and validated by health practitioners. Answers were reported using a 5-point Likert scale. The responses were summed up to give a total score for each respondent. Respondents who scored above or equal 75% of the total score was considered positive perception or favorable attitude. Binary logistic regression analysis was used to identify factors influencing participants' perception and attitude toward taking antidepressants. RESULTS: A total of 991 subjects were surveyed. The majority of women had negative perceptions and favorable attitudes towards using antidepressants during pregnancy reaching 64%. While women with positive perceptions and favorable attitudes represented about 20% of the study subjects. Participants reported that social stigma, religious beliefs, and fear of addiction significantly influenced their attitudes toward antidepressant use. CONCLUSIONS: This study explores women's perceptions of depression and antidepressant use, revealing that a significant proportion of Saudi women have a negative perception. The research emphasizes the need for tailored awareness programs to promote informed decision-making regarding antidepressant usage among Saudi women.


Assuntos
Antidepressivos , Depressão , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Feminino , Estudos Transversais , Antidepressivos/uso terapêutico , Arábia Saudita , Adulto , Gravidez , Depressão/psicologia , Depressão/tratamento farmacológico , Adulto Jovem , Inquéritos e Questionários , Complicações na Gravidez/psicologia , Complicações na Gravidez/tratamento farmacológico , Estigma Social , Adolescente , Pessoa de Meia-Idade
6.
Eur Arch Otorhinolaryngol ; 281(10): 5363-5373, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38977475

RESUMO

PURPOSE: This study aimed to assess the efficacy and safety of ballon dilation of the eustachian tube (BDET) in adult population suffering from Eustachian tube dysfunction (ETD). METHODS: Following PRISMA criteria, a systematic review was conducted by searching PubMed, Cochrane, and Embase databases from January 2015 to March 2024. The primary outcomes included Eustachian Tube Score (ETS), tympanometry, and Valsalva maneuver. The quality of studies was assessed using the Quality in Prognostic Studies (QUIPS) instrument. RESULTS: Overall, 11 studies were incorporated into the systematic review: two RCTs, three prospective investigations, and six retrospective studies. The balloon dilation in all investigations was performed using either Spiggle & Theis or Acclarent catheters for balloon dilation. There was heterogeneity across studies examining the effect of BDET on persistent ETD in terms of patient selection, period of follow-up, administration of conservative or surgical therapies, and use of assessment methods. Overall, the treatment yielded alleviation of symptoms, which either exhibited stability over time or demonstrated further improvement after an average duration of follow-up. Moreover, the incidence of complications was categorized as low and resolving spontaneously. The majority of the studies exhibited a high risk of bias related to confounding variables, and consequently, the overall risk of bias across most studies was considered high. CONCLUSION: The findings suggest BDET holds promise for ETD treatment, reducing symptom severity with minimal complications. Nonetheless, there is a need for improved studies that adhere to established indications, methodologies, and outcomes to establish a more robust body of evidence.


Assuntos
Dilatação , Otopatias , Tuba Auditiva , Humanos , Tuba Auditiva/fisiopatologia , Dilatação/métodos , Otopatias/terapia , Adulto , Resultado do Tratamento
7.
Environ Monit Assess ; 196(4): 365, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483634

RESUMO

Identifying factors contributing to water salinity is paramount in efficiently managing limited water resources in arid environments. The primary objective of this study is to enhance understanding regarding the hydrochemistry, source, and mechanism of water salinity, as well as to assess the suitability of water for various uses in southern Iraq. The groundwater samples were collected from water wells and springs and analyzed for major cations and anions along with stable isotopes (δ18O and δ2H) to accomplish the objective. The analysis of major ion chemistry, hydrochemical techniques, principal component analysis (PCA), and isotope signatures were adopted to determine the primary factors contributing to water mineralization. The study inferred that evaporation and geological processes encompassing water-rock interactions, such as dissolution precipitation and ion exchange, were key processes. The stable isotope analysis revealed that the water originated from meteoric sources and underwent significant evaporation during or before infiltration. The utility assessment of water samples indicates that most samples are not appropriate for consumption and are significantly below the established standards for potable water. In contrast, a significant portion of the groundwater samples were found to meet the criteria for irrigation suitability by adopting Wilcox and the US Salinity Laboratory criteria. The groundwater could be considered for irrigation with proper salinity control management. Overall, this study has significantly improved the understanding of the hydrogeochemical regimes and acts as a first step toward the sustainable utilization of water resources.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Salinidade , Iraque , Poluentes Químicos da Água/análise , Água Subterrânea/química , Água Potável/química , Isótopos/análise
8.
Saudi Pharm J ; 32(1): 101890, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38192383

RESUMO

Purpose: Saudi Arabia is one of the leading nations in the world in terms of the high frequency of chronic diseases and their associated risk factors. Knowledge and awareness are crucial for pharmacists to play an active role in the prevention of cardiovascular diseases (CVD). The current study assessed the pharmacists' knowledge, attitude, and practice to determine the potential differences with respect to their respective practice settings toward CVD prevention and related health promotions. Methods: It is a cross-sectional study targeted the registered pharmacists in the Kingdom of Saudi Arabia. An online questionnaire was prepared, and the link was circulated through various social media platforms. Descriptive statistics, multivariate linear regression analysis and chi square test were used to analyze the data accordingly. Results: A total of 324 pharmacists were included in the study. Among these, 157 (48.4 %) were community pharmacists, and the remaining were hospital pharmacists (51.6 %). No significant differences in knowledge scores were observed between community and hospital pharmacists. The mean attitude score among community and hospital pharmacists was found to be 26.40 ± 5.125 and 25.09 ± 5.393 respectively, which was statistically significant (p = 0.026). Similarly, the total practice scores across the settings were statistically significant (p = 0.02). Gender plays a significant role in terms of knowledge scores among both community and hospital pharmacists (p = 0.016 & 0.029). Gender, professional practice experience, and number of prescriptions handled and prescriptions with CVD medications showed significant differences in the distribution of positive attitudes and good practice frequency between community and hospital pharmacists. Conclusion: It is evident that there is a deficiency in knowledge among hospital pharmacists compared to community pharmacists. Which indicates that there is a need for a rigorous continuous pharmacy education covering the fundamental aspects of CVD primary prevention and health promotion among pharmacists, given more focus on hospital pharmacists.

9.
Evid Based Dent ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39289553

RESUMO

DESIGN: A single-center (university-setting), prospective, longitudinal, split-mouth, single-blind, randomized controlled clinical trial investigated peri-implant parameters of bone-level implants restored with either screw-retained prostheses connected directly to the implants or with intermediate abutments over a 3-year period. The study adhered to the ethical principles of the Helsinki Declaration and the CONSORT guidelines. Ethical approval was granted, and the trial was registered at Clinicaltrials.gov . CASE SELECTION: Participants included were over 18 years of age, had a plaque index below 25%, and were missing at least two adjacent teeth, allowing for rehabilitation with screw-retained fixed partial prostheses over two implants and 2-4 prosthetic units. Exclusion criteria included long-term use of medications affecting bone metabolism, smoking more than 10 cigarettes per day, history of local radiotherapy, untreated periodontitis, and the need for rehabilitation in the anterior sextant of the maxilla. The primary clinical outcome was marginal bone loss (MBL), while secondary outcomes included probing pocket depth (PPD), plaque index (PI), bleeding on probing (BOP), and patient-reported outcomes (PROs). STUDY TIMELINE: The study schedule included a screening (visit 1), implant surgery (visit 2), stage-two 8 weeks post-surgery (visit 3), impressions taken 4 weeks post stage-two (visit 4), baseline standardized radiograph (visit 5), followed by 6-month (visit 6), 12-month (visit 7), and 36-month (visit 8) follow-up visits. DATA ANALYSIS: Descriptive statistics and quantitative measures included means, standard deviations (SDs), minimum and maximum values, and 95% confidence intervals (CIs). Clinical parameters (six sites per implant) measured were MBL, PPD, PI, and BOP. Paired t tests were utilized for intragroup comparisons across different time points and intergroup comparisons at each time point. PROs at 36 months were compared using Student's t test. The alpha significance level was set at 0.05. RESULTS: The study included 36 patients (72 implants), with two not completing the follow-up due to death and relocation. No implants showed signs of inflammation or mobility. Mean interproximal bone level (IBL) at baseline was 0.13 mm ± 0.15 mm for the control group and 0.10 ± 0.13 mm for the test group. At the 36-month follow-up, mean IBL was 0.13 ± 0.18 mm for the control group and 0.20 ± 0.24 mm for the test group, with no significant differences (F(1, 32) = 1.06; p > 0.05). Clinical parameters (PPD, BOP, PI) at 36 months showed no significant differences between groups. Minor complications occurred in 6.7% of the control group and 5.3% of the test group. PROs indicated no significant differences in general satisfaction, esthetics, comfort, phonetics, and masticatory function between the groups. CONCLUSIONS: After a 36-month follow-up, bone-level implants restored with CAD/CAM prostheses directly connected to the implants displayed similar clinical outcomes, PROs, and marginal bone level changes as those restored with intermediate standardized abutments.

10.
J Oncol Pharm Pract ; 29(3): 755-759, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35912495

RESUMO

INTRODUCTION: Isotretinoin is a synthetic vitamin A derivative, administered off-label as maintenance therapy for neuroblastoma. This report addresses the challenge of administering isotretinoin to children, given its availability as soft gelatin capsules only. CASE REPORT: A 3-year-old boy diagnosed with stage IV neuroblastoma has undergone multimodal therapy, including six cycles of chemotherapy, followed by tumor resection and radiotherapy. Later, he was initiated on immunotherapy and prescribed isotretinoin 50 mg orally twice daily for two weeks, before each immunotherapy cycle. Isotretinoin is not available in liquid formulation and the patient could not swallow isotretinoin capsules. Therefore, pharmacist counseling was required to ensure appropriate administration of the drug. MANAGEMENT AND OUTCOMES: The patient's parents were instructed to pierce prescribed capsules, and empty and dilute their contents into a small glass containing olive oil after taking safety measures. Isotretinoin's stability in olive oil for 72 h was compared using high-performance liquid chromatography to its stability in soybean oil. The recovery rates were 98.62% and 98.3%, respectively. Drug miscibility was not an issue as isotretinoin is lipophilic. Therefore, it could be administered easily without considerable remaining on the interior wall of the glass. DISCUSSION: To the best of our knowledge, this is the first report that suggests a practical method for administering isotretinoin in liquid form, particularly in pediatric oncology patients. Isotretinoin was noted to be stable in olive oil and its exposure to light and oxygen would not be an issue given the short time from preparation to administration and the low emphasis on exposure by the manufacturer when such a method is recommended.


Assuntos
Isotretinoína , Neuroblastoma , Criança , Masculino , Humanos , Pré-Escolar , Isotretinoína/uso terapêutico , Azeite de Oliva/uso terapêutico , Neuroblastoma/tratamento farmacológico , Terapia Combinada , Administração Oral
11.
Molecules ; 28(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37513271

RESUMO

Sustainable alternatives to conventional fuels have emerged recently, focusing on a hydrogen-based economy. The idea of using hydrogen (H2) as an energy carrier is very promising due to its zero-emission properties. The present study investigates the formic acid (FA) decomposition for H2 generation using a commercial 5 wt.% Pd/C catalyst. Three different 2D microreactor configurations (packed bed, single membrane, and double membrane) were studied using computational fluid dynamics (CFD). Parameters such as temperature, porosity, concentration, and flow rate of reactant were investigated. The packed bed configuration resulted in high conversions, but due to catalyst poisoning by carbon monoxide (CO), the catalytic activity decreased with time. For the single and double membrane microreactors, the same trends were observed, but the double membrane microreactor showed superior performance compared with the other configurations. Conversions higher than 80% were achieved, and even though deactivation decreased the conversion after 1 h of reaction, the selective removal of CO from the system with the use of membranes lead to an increase in the conversion afterwards. These results prove that the incorporation of membranes in the system for the separation of CO is improving the efficiency of the microreactor.

12.
Molecules ; 28(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36771180

RESUMO

Wilson's disease causes copper accumulation in the liver and extrahepatic organs. The available therapies aim to lower copper levels by various means. However, a potent drug that can repair the damaged liver and brain tissue is needed. Silymarin has hepatoprotective, antioxidant, and cytoprotective properties. However, poor oral bioavailability reduces its efficacy. In this study, a "thin film hydration method" was used for synthesizing silymarin-encapsulated liposome nanoparticles (SLNPs) and evaluated them against copper toxicity, associated liver dysfunction and neurobehavioral abnormalities in Wistar rats. After copper toxicity induction, serological and behavioral assays were conducted to evaluate treatment approaches. Histological examination of the diseased rats revealed severe hepatocyte necrosis and neuronal vacuolation. These cellular degenerations were mild in rats treated with SLNPs and a combination of zinc and SLNPs (ZSLNPs). SLNPs also decreased liver enzymes and enhanced rats' spatial memory significantly (p = 0.006) in the diseased rats. During forced swim tests, SLNPs treated rats exhibited a 60-s reduction in the immobility period, indicating reduced depression. ZSLNPs were significantly more effective than traditional zinc therapy in decreasing the immobility period (p = 0.0008) and reducing liver enzymes, but not in improving spatial memory. Overall, SLNPs enhanced oral silymarin administration and managed copper toxicity symptoms.


Assuntos
Degeneração Hepatolenticular , Silimarina , Ratos , Animais , Ratos Wistar , Silimarina/uso terapêutico , Cobre/farmacologia , Lipossomos/farmacologia , Fígado , Degeneração Hepatolenticular/tratamento farmacológico , Zinco/farmacologia , Zinco/uso terapêutico
13.
Molecules ; 28(10)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37241888

RESUMO

Quercetin (QtN) displays low systemic bioavailability caused by poor water solubility and instability. Consequently, it exerts limited anticancer action in vivo. One solution to increase the anticancer efficacy of QtN is the use of appropriate functionalized nanocarriers that preferentially target and deliver the drug to the tumor location. Herein, a direct advanced method was designed to develop water-soluble hyaluronic acid (HA)-QtN-conjugated silver nanoparticles (AgNPs). HA-QtN reduced silver nitrate (AgNO3) while acting as a stabilizing agent to produce AgNPs. Further, HA-QtN#AgNPs served as an anchor for folate/folic acid (FA) conjugated with polyethylene glycol (PEG). The resulting PEG-FA-HA-QtN#AgNPs (further abbreviated as PF/HA-QtN#AgNPs) were characterized both in vitro and ex vivo. Physical characterizations included UV-visible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), particle size (PS) and zeta potential (ZP) measurements, and biopharmaceutical evaluations. The biopharmaceutical evaluations included analyses of the cytotoxic effects on the HeLa and Caco-2 cancer cell lines using the MTT assay; cellular drug intake into cancer cells using flow cytometry and confocal microscopy; and blood compatibility using an automatic hematology analyzer, a diode array spectrophotometer, and an enzyme-linked immunosorbent assay (ELISA). The prepared hybrid delivery nanosystem was hemocompatible and more oncocytotoxic than the free, pure QtN. Therefore, PF/HA-QtN#AgNPs represent a smart nano-based drug delivery system (NDDS) and could be a promising oncotherapeutic option if the data are validated in vivo.


Assuntos
Produtos Biológicos , Nanopartículas Metálicas , Neoplasias , Humanos , Ácido Hialurônico/química , Quercetina/farmacologia , Nanopartículas Metálicas/química , Células CACO-2 , Prata , Polietilenoglicóis/química , Água , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Entropy (Basel) ; 25(3)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36981304

RESUMO

Entanglement swapping is gaining widespread attention due to its application in entanglement distribution among different parts of quantum appliances. We investigate the entanglement swapping for pure and noisy systems, and argue different entanglement quantifiers for quantum states. We explore the relationship between the entanglement of initial states and the average entanglement of final states in terms of concurrence and negativity. We find that if initial quantum states are maximally entangled and we make measurements in the Bell basis, then average concurrence and average negativity of final states give similar results. In this case, we simply obtain the average concurrence (average negativity) of the final states by taking the product of concurrences (negativities) of the initial states. However, the measurement in non-maximally entangled basis during entanglement swapping degrades the average swapped entanglement. Further, the product of the entanglement of the initial mixed states provides an upper bound to the average swapped entanglement of final states obtained after entanglement swapping. The negativity work well for weak entangled noisy states but concurrence gives better results for relatively strong entanglement regimes. We also discuss how successfully the output state can be used as a channel for the teleportation of an unknown qubit.

15.
Neurocrit Care ; 36(3): 772-780, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34697769

RESUMO

BACKGROUND: Acute myocardial infarction (AMI) is the rarest and least studied cardiac complication of aneurysmal subarachnoid hemorrhage (aSAH). Precise estimates of the incidence of AMI after aSAH are unavailable. Our goal was to estimate the incidence of registry-based AMI (rb-AMI) after aSAH and determine its association with clinical outcomes. METHODS: Adult patients with aSAH in the National Inpatient Samples from 2002 to 2014 were included in the study. We evaluated risk factors for rb-AMI using univariate and multivariate regression models. Clinical outcomes that were assessed included functional status at discharge, in-patient mortality, length of stay, and total hospitalization cost, adjusting for patient demographics and cardiovascular risk factors through an inverse probability weighted analysis. Subgroup analyses were further performed stratified by rb-AMI type (ST-segment elevation myocardial infarction [STEMI] vs. non-STEMI [NSTEMI]). RESULTS: A total of 139,734 patients with aSAH were identified, 3.6% of whom had rb-AMI. NSTEMI was the most common type of rb-AMI occurring after aSAH (71% vs. 29% for NSTEMI vs. STEMI, respectively). Patient characteristics associated with higher odds of rb-AMI included age, female sex, poor aSAH grade, and various cardiovascular risk factors. Rb-AMI was also associated with poor functional status at discharge, higher in-hospital mortality, and a longer and more costly hospital stay. CONCLUSIONS: Rb-AMI occurs in 3.6% of patients with aSAH and is associated with poor functional status at discharge, higher in-patient mortality, and a longer and more costly hospitalization. Differentiating between different types of rb-AMI would be important in optimizing the management of patients with aSAH. Our definition of rb-AMI likely includes patients with neurogenic stress cardiomyopathy, which may confound the results.


Assuntos
Infarto do Miocárdio , Infarto do Miocárdio sem Supradesnível do Segmento ST , Infarto do Miocárdio com Supradesnível do Segmento ST , Hemorragia Subaracnóidea , Adulto , Feminino , Humanos , Incidência , Infarto do Miocárdio/epidemiologia , Sistema de Registros , Fatores de Risco , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/epidemiologia
16.
BMC Med Educ ; 22(1): 475, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35725450

RESUMO

BACKGROUND: The higher education institutions worldwide have been transformed unexpectedly to online teaching. This sudden movement from blended learning or traditional face-to-face teaching has severely disrupted university activities and posed many challenges for teaching staff, who were asked to develop online versions of their courses overnight. This study explores the effect of the current changes in education style and working from home on the stress and burnout levels of teaching staff. METHODS: This study utilized a cross-sectional design, whereby 278 participants (faculty and course instructors) from 17 campuses of one of the largest colleges in United Arab Emirates completed a web-based survey. Numerous instruments were utilized to obtain the following data: participants demographics; their perceived stress during online teaching; their perception of the impact of teaching from home on their family's daily life, physical health, mental health and ability to cope with stress; burnout level; and their satisfaction with online teaching. RESULTS: Around 60% of participants reported moderate stress level during online teaching (moderate stress = 5 to 8) under COVID-19 (M 6.21 ± 2.26). An independent sample t-test and ANOVA tests revealed that participants with 7-10 years of online teaching experience reported more stress than participants who have 4-6 years online teaching experience (M 7.29, ±1.11 Vs. 5.30, ±2.69; P = 0.04). Moreover, multiple regression analysis showed that higher stress levels and lower satisfaction with the online teaching experience were associated with more significant personal and working burnout. Married participants with school-age children were at greater risk of personal burnout. CONCLUSION: The transition to remote education imposed mental burdens and stress on faculty members. Supportive professional development strategies to enrich faculty with online teaching skills are urgently required.


Assuntos
Esgotamento Profissional , COVID-19 , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Esgotamento Psicológico , COVID-19/epidemiologia , Criança , Estudos Transversais , Docentes/psicologia , Humanos
17.
J Vet Pharmacol Ther ; 45(3): 283-290, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35170771

RESUMO

The study objective was to determine the disposition of gamithromycin in plasma, peripheral blood polymorphonuclear cells (PMNs), pulmonary epithelial lining fluid (PELF), and bronchoalveolar lavage (BAL) cells in alpacas. A single subcutaneous injection of gamithromycin (6.6 mg/kg) was administered to six healthy adult alpacas. At various time points after administration, gamithromycin concentrations were analyzed via LC-MS/MS in plasma, PMNs, PELF, and BAL cells until Day 14 post-injection. Plasma gamithromycin concentrations were measured in all six alpacas; the remaining three body compartments were analyzed in four alpacas. Gamithromycin rapidly concentrated in blood PMNs, BAL cells, and PELF. Shorter Tmax , and lower Cmax, and AUC were observed in plasma than in the other three compartments. Cmax was highest in BAL cells (26001.80 ± 12400.00 ng/ml) and PMNs (2573.00 ± 963.30 ng/ml) compared to PELF (660.80 ± 413.70 ng/ml) and plasma (452.30 ± 196.20 ng/ml). Mean terminal half-lives were 72.60 ± 14.10 h in plasma, 56.60 ± 10.60 h in PELF, 62.80 ± 85.30 h in PMNs, and 93.60 ± 124.80 h in BAL cells. No injection site reactions occurred. One alpaca developed colic but no other adverse reactions were noted. Overall, gamithromycin was highly concentrated in white blood cells and pulmonary fluids/cells. Clinical utilization of gamithromycin in alpacas should be done with caution until further investigation of potential for colic.


Assuntos
Camelídeos Americanos , Cólica , Animais , Antibacterianos/farmacocinética , Cromatografia Líquida/veterinária , Cólica/veterinária , Macrolídeos , Espectrometria de Massas em Tandem/veterinária
18.
Int J Mol Sci ; 23(6)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35328726

RESUMO

Tricyclodecan-9-yl xanthogenate (D609) is a synthetic tricyclic compound possessing a xanthate group. This xanthogenate compound is known for its diverse pharmacological properties. Over the last three decades, many studies have reported the biological activities of D609, including antioxidant, antiapoptotic, anticholinergic, anti-tumor, anti-inflammatory, anti-viral, anti-proliferative, and neuroprotective activities. Its mechanism of action is extensively attributed to its ability to cause the competitive inhibition of phosphatidylcholine (PC)-specific phospholipase C (PC-PLC) and sphingomyelin synthase (SMS). The inhibition of PCPLC or SMS affects secondary messengers with a lipidic nature, i.e., 1,2-diacylglycerol (DAG) and ceramide. Various in vitro/in vivo studies suggest that PCPLC and SMS inhibition regulate the cell cycle, block cellular proliferation, and induce differentiation. D609 acts as a pro-inflammatory cytokine antagonist and diminishes Aß-stimulated toxicity. PCPLC enzymatic activity essentially requires Zn2+, and D609 might act as a potential chelator of Zn2+, thereby blocking PCPLC enzymatic activity. D609 also demonstrates promising results in reducing atherosclerotic plaque formation, post-stroke cerebral infarction, and cancer progression. The present compilation provides a comprehensive mechanistic insight into D609, including its chemistry, mechanism of action, and regulation of various pharmacological activities.


Assuntos
Hidrocarbonetos Aromáticos com Pontes , Tionas , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Norbornanos , Tiocarbamatos , Tionas/farmacologia , Fosfolipases Tipo C/metabolismo
19.
Int J Mol Sci ; 23(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36430919

RESUMO

Upconversion nanoparticles (UCNPs) and carbon quantum dots (CQDs) have recently received a lot of attention as promising materials to improve the stability and efficiency of perovskite solar cells (PSCs). This is because they can passivate the surfaces of perovskite-sensitive materials and act as a spectrum converter for sunlight. In this study, we mixed and added both promising nanomaterials to PSC layers at the ideal mixing ratios. When compared to the pristine PSCs, the fabricated PSCs showed improved power conversion efficiency (PCE), from 16.57% to 20.44%, a higher photocurrent, and a superior fill factor (FF), which increased from 70% to 75%. Furthermore, the incorporation of CQDs into the manufactured PSCs shielded the perovskite layer from water contact, producing a device that was more stable than the original.


Assuntos
Nanopartículas , Pontos Quânticos , Carbono , Luz Solar
20.
Int J Mol Sci ; 23(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36555575

RESUMO

Antibacterial restorative materials against caries-causing bacteria are highly preferred among high-risk patients, such as the elderly, and patients with metabolic diseases such as diabetes. This study aimed to enhance the antibacterial potential of resin composite with Magnesium-doped Zinc oxide (Mg-doped ZnO) nanoparticles (NPs) and to look for their effectiveness in the alloxan-induced diabetic model. Hexagonal Mg-doped ZnO NPs (22.3 nm diameter) were synthesized by co-precipitation method and characterized through ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analysis. The Mg-doped ZnO NPs (1, 2.5 and 5% w/w) were then evaluated for antibacterial activity using a closed system in vitro biofilm model. Significant enhancement in the antibacterial properties was observed in composites with 1% Mg-doped ZnO compared to composites with bare ZnO reinforced NPs (Streptococcus mutans, p = 0.0005; Enterococcus faecalis, p = 0.0074, Saliva microcosm, p < 0.0001; Diabetic Saliva microcosm, p < 0.0001). At 1−2.5% Mg-doped ZnO NPs concentration, compressive strength and biocompatibility of composites were not affected. The pH buffering effect was also achieved at these concentrations, hence not allowing optimal conditions for the anaerobic bacteria to grow. Furthermore, composites with Mg-doped ZnO prevented secondary caries formation in the secondary caries model of alloxan-induced diabetes. Therefore, Mg-doped ZnO NPs are highly recommended as an antibacterial agent for resin composites to avoid biofilm and subsequent secondary caries formation in high-risk patients.


Assuntos
Diabetes Mellitus , Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Humanos , Idoso , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Zinco , Aloxano , Magnésio/farmacologia , Óxido de Magnésio/farmacologia , Óxido de Magnésio/uso terapêutico , Suscetibilidade à Cárie Dentária , Nanopartículas/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Testes de Sensibilidade Microbiana
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