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1.
Plants (Basel) ; 13(5)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38475504

RESUMEN

Since Astragalus is a genus with many important medicinal plant species, the present work aimed to investigate the phytochemical composition and some biological activities of Astragalus gymnolobus. The methanolic fractions of four organs (stems, flowers, leaves, root and whole plant) were quantified and identified by Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry (LC-ESI-MS/MS) analysis. Hesperidin, hyperoside, p-hydroxybenzoic acid, protocatechuic acid and p-coumaric acid were identified as main compounds among the extracts. Among all cells, leaf methanol (Lm) extract had the highest cytotoxic effect on HeLa cells (IC50 = 0.069 µg/mL). Hesperidin, the most abundant compound in A. gymnolobus extract, was found to show a strong negative correlation with the cytotoxic effect observed in HeLa cells according to Pearson correlation test results and to have the best binding affinity to targeted proteins by docking studies. The antimicrobial activity results indicated that the most susceptible bacterium against all extracts was identified as Streptococcus pyogenes with 9-11 mm inhibition zone and 8192 mg/mL MIC value. As a result of the research, it was suggested that A. gymnolobus could be considered as a promising source that contributes to the fight against cancer.

2.
Sci Rep ; 13(1): 20733, 2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-38007559

RESUMEN

Quantum-tunneling metal-insulator-metal (MIM) diodes have emerged as a significant area of study in the field of materials science and electronics. Our previous work demonstrated the successful fabrication of these diodes using atmospheric pressure chemical vapor deposition (AP-CVD), a scalable method that surpasses traditional vacuum-based methods and allows for the fabrication of high-quality Al2O3 films with few pinholes. Here, we show that despite their extremely small size 0.002 µm2, the MIM nanodiodes demonstrate low resistance at zero bias. Moreover, we have observed a significant enhancement in resistance by six orders of magnitude compared to our prior work, Additionally, we have achieved a high responsivity of 9 AW-1, along with a theoretical terahertz cut-off frequency of 0.36 THz. Our approach provides an efficient alternative to cleanroom fabrication, opening up new opportunities for manufacturing terahertz-Band devices. The results of our study highlight the practicality and potential of our method in advancing nanoelectronics. This lays the foundation for the development of advanced quantum devices that operate at terahertz frequencies, with potential applications in telecommunications, medical imaging, and security systems.

3.
Micromachines (Basel) ; 14(9)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37763870

RESUMEN

Enhancing the output power of triboelectric nanogenerators (TENGs) requires the creation of micro or nano-features on polymeric triboelectric surfaces to increase the TENGs' effective contact area and, therefore, output power. We deploy a novel bench-top fabrication method called dynamic Scanning Probe Lithography (d-SPL) to fabricate massive arrays of uniform 1 cm long and 2.5 µm wide nano-features comprising a 600 nm deep groove (NG) and a 600 nm high triangular prism (NTP). The method creates both features simultaneously in the polymeric surface, thereby doubling the structured surface area. Six thousand pairs of NGs and NTPs were patterned on a 6×5 cm2 PMMA substrate. It was then used as a mold to structure the surface of a 200 µm thick Polydimethylsiloxane (PDMS) layer. We show that the output power of the nano-structured TENG is significantly more than that of a TENG using flat PDMS films, at 12.2 mW compared to 2.2 mW, under the same operating conditions (a base acceleration amplitude of 0.8 g).

4.
Org Biomol Chem ; 21(28): 5809-5826, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37401334

RESUMEN

Effective synthesis of prolinamides of 2-(2-aminocyclohexyl)phenols has been accomplished. The novel prolinamides are demonstrated to catalyze the direct aldol reaction between ketones and aldehydes with high stereoselectivity, thus affording up to 99 : 1 anti/syn diastereomeric and 99 : 1 enantiomeric ratio. Experimental results as well as computational investigations have revealed that the electrophile (e.g. aldehyde) is activated by dual hydrogen bonding with the amide NH and phenolic OH group of the catalyst. A rather large spacing between the H-bond donor groups and its conformational flexibility are remarkable structural features of the most enantioselective catalyst.

5.
Micromachines (Basel) ; 14(7)2023 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-37512784

RESUMEN

Conventional packaging and interconnection methods for two-terminal devices, e.g., diodes often involve expensive and bulky equipment, introduce parasitic effects and have reliability issues. In this study, we propose a built-in packaging method and evaluate its performance compared to probing and wire bonding methods. The built-in packaging approach offers a larger overlap area, improved contact resistance, and direct connection to testing equipment. The experimental results demonstrate a 12% increase in current, an 11% reduction in resistance, and improved performance of the diode. The proposed method is promising for enhancing sensing applications, wireless power transmission, energy harvesting, and solar rectennas. Overall, the built-in packaging method offers a simpler, cheaper, more compact and more reliable packaging solution, paving the way for more efficient and advanced technologies in these domains.

6.
Diagnostics (Basel) ; 13(14)2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37510124

RESUMEN

The most common cause of death in patients with Duchenne muscular dystrophy (DMD) is cardiomyopathy. Our aim was to investigate the relationship between the Tpeak-Tend (Tp-e) interval and the premature ventricular contraction (PVC) burden and therefore early arrhythmic risk and cardiac involvement in DMD patients. Twenty-five patients with DMD followed by pediatric cardiology were included in the study. Those with a frequency of <1% PVC in the 24 h Holter were assigned to Group 1 (n = 15), and those with >1% were assigned to Group 2 (n = 10). Comparisons were made with healthy controls (n = 27). Left ventricular ejection fraction (LVEF) was lowest in Group 2 and highest in the control group (p < 0.001). LV end-diastolic diameter was greater in Group 2 than in Group 1 and the control group (p = 0.005). Pro-BNP and troponin levels were higher in Group 1 and Group 2 than in the control group (p = 0.001 and p < 0.001, respectively). Tp-e interval was longer in Group 2 compared to Group 1 and the control group (p < 0.001). The LVEF (OR 0.879, 95% CI 0.812-0.953; p = 0.002) and Tp-e interval (OR 1.181, 95% CI 1.047-1.332; p = 0.007) were independent predictors of PVC/24 h frequency of >1%. A Tp-e interval > 71.65 ms predicts PVC > 1%, with a sensitivity of 80% and a specificity of 90% (AUC = 0.842, 95% CI (0.663-1.000), p = 0.001). Determination of Tp-e prolongation from ECG data may help in the determination of cardiac involvement and early diagnosis of arrhythmic risk in DMD.

7.
Nano Lett ; 23(10): 4298-4303, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37166106

RESUMEN

Solution-processed colloidal quantum dots (CQDs) are promising materials for photodetectors operating in the short-wavelength infrared region (SWIR). Devices typically rely on CQD-based hole transport layers (HTL), such as CQDs treated using 1,2-ethanedithiol. Herein, we find that these HTL materials exhibit low carrier mobility, limiting the photodiode response speed. We develop instead inverted (p-i-n) SWIR photodetectors operating at 1370 nm, employing NiOx as the HTL, ultimately enabling 4× shorter fall times in photodiodes (∼800 ns for EDT and ∼200 ns for NiOx). Optoelectronic simulations reveal that the high carrier mobility of NiOx enhances the electric field in the active layer, decreasing the overall transport time and increasing photodetector response time.

8.
Nanotechnology ; 34(41)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37257435

RESUMEN

Among the many recently developed photo-catalytic materials, graphitic carbon nitride (g-C3N4) shows great promise as a catalytic material for water splitting, hydrogen generation, and related catalytic applications. Herein, synthesized bulk g-C3N4is simply irradiated under a 35 fs pulse at mixed photon energies (800 nm and its second harmonic). g-C3N4was synthesized from melamine following a facile thermal polymerization procedure. The prepared material was introduced, in an aqueous environment, to the femtosecond laser for various lengths of time. The treated material demonstrates a significant increase in surface area, relative to the untreated samples, indicating that irradiation is a successful method for exfoliation. The subsequent characterization reveals that the mixed irradiation process drives significant defect generation and sheet growth, which is not seen under 800 nm irradiation. Extended mixed irradiation results in 4 nm thick nanosheets with lateral dimensions 4× that of the bulk material. The treated material shows improved dye absorption/removal. This novel method of defect generation and nanosheet growth shows great potential as a g-C3N4pre-treatment method for co-catalytic applications. Herein it is shown that femtosecond laser irradiation drives exfoliation beyond 100 nm particle sizes, and sheet-like morphologies under extended irradiation, which must be taken into account when using this method to improve material performance.

9.
Artículo en Inglés | MEDLINE | ID: mdl-36921206

RESUMEN

Since SARS-CoV-2 disease (COVID-19) has been labeled as a pandemic, it took the spotlight in the differential diagnosis for patients presenting with acute respiratory and systemic symptoms. Leptospirosis is one of the most common zoonoses in the world, yet it is mainly a disease of differential diagnosis for places that do not have it as an endemic. Due to the high burden of COVID-19 on the healthcare field, patients suffering from other infections may have been inadvertently neglected. COVID-19 infection can mimic other infectious diseases and can confuse physicians in their search for a confirmatory diagnosis. Nonetheless, it is very crucial to broaden the differential diagnosis and keep diseases like leptospirosis within the differential diagnosis despite its rarity, especially in patients presenting with unexplained systemic infectious symptoms. This is a unique case of a patient who presented with dyspnea, jaundice and change in urine color who was suspected to be COVID-19 positive. After a detailed investigation, the patient was diagnosed with leptospirosis instead of COVID-19 and was treated with plasmapheresis and antibiotics accordingly.


Asunto(s)
COVID-19 , Leptospirosis , Animales , Humanos , Pandemias , SARS-CoV-2 , Leptospirosis/complicaciones , Leptospirosis/diagnóstico , Zoonosis
10.
Sci Rep ; 13(1): 1949, 2023 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-36732355

RESUMEN

It is unclear whether metacognitive judgments are made on the basis of domain-generality or domain-specificity. In the current study, we compared both behavioral and event-related potential (ERP) correlates of retrospective (retrospective confidence judgments: RCJs), and prospective (feeling of knowing: FOK) metacognitive judgments during episodic and semantic memory tasks in 82 participants. Behavioral results indicated that FOK judgments reflect a domain-specific process, while RCJ reflect a domain-general process. RCJ and FOK judgments produced similar ERP waveforms within the memory tasks, but with different temporal dynamics; thus supporting the hypothesis that retrospective and prospective metacognitive judgments are distinct processes. Our ERP results also suggest that metacognitive judgments are linked to distributed neural substrates, rather than purely frontal lobe functioning. Furthermore, the role of intra-subject and inter-subject differences in metacognitive judgments across and within the memory tasks are highlighted.


Asunto(s)
Juicio , Memoria Episódica , Humanos , Recuerdo Mental , Semántica , Estudios Retrospectivos , Estudios Prospectivos , Potenciales Evocados
11.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1422786

RESUMEN

ABSTRACT Since SARS-CoV-2 disease (COVID-19) has been labeled as a pandemic, it took the spotlight in the differential diagnosis for patients presenting with acute respiratory and systemic symptoms. Leptospirosis is one of the most common zoonoses in the world, yet it is mainly a disease of differential diagnosis for places that do not have it as an endemic. Due to the high burden of COVID-19 on the healthcare field, patients suffering from other infections may have been inadvertently neglected. COVID-19 infection can mimic other infectious diseases and can confuse physicians in their search for a confirmatory diagnosis. Nonetheless, it is very crucial to broaden the differential diagnosis and keep diseases like leptospirosis within the differential diagnosis despite its rarity, especially in patients presenting with unexplained systemic infectious symptoms. This is a unique case of a patient who presented with dyspnea, jaundice and change in urine color who was suspected to be COVID-19 positive. After a detailed investigation, the patient was diagnosed with leptospirosis instead of COVID-19 and was treated with plasmapheresis and antibiotics accordingly.

12.
Clin Lab ; 68(12)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36546745

RESUMEN

BACKGROUND: Galectin-3 has been shown to play a key pathophysiological role in pulmonary associated inflammatory response and lung fibrosis in COVID-19 and is a mediator for viral adhesion. However, there is limited data about its potential role in severity and prognosis of COVID-19. This study aimed to investigate the predictive role of serum galectin-3 concentrations in the severe clinical outcomes of hospitalized COVID-19 patients: the severity of pneumonia, in-hospital mortality, and the need for intensive care unit (ICU) admission. METHODS: This single-center study included 68 patients with laboratory- and radiologically-confirmed COVID-19 admitted to our emergency department. The study population was divided into patients with primary clinical out-comes (n = 32) and those without (n = 36). The need for ICU admission and/or in-hospital mortality were the primary clinical endpoints. The study group was also classified based on pneumonia severity: severe or mild/moderate. Blood samples were collected within 48 hours of admission to estimate serum galectin-3 concentrations. RESULTS: Multivariate regression analysis showed that lower concentrations of galectin-3 and arterial oxygen saturation (SpO2) were independently associated with the primary clinical outcomes (OR = 0.951, p = 0.035; OR = 0.862, p = 0.017, respectively); increased concentrations of galectin-3 were an independent predictor of severe pneumonia (OR = 1.087, p = 0.016). In the receiver operating characteristics curve analysis, serum galectin-3 concentrations at hospital admission predicted pneumonia severity with 52.1% sensitivity and 90% specificity with a cutoff of 38.76 ng/mL. CONCLUSIONS: Circulating galectin-3 at hospital admission could be a useful biomarker for identifying COVID-19 patients at high risk for severe pneumonia.


Asunto(s)
COVID-19 , Neumonía , Humanos , Galectina 3 , SARS-CoV-2 , Neumonía/diagnóstico , Pronóstico , Unidades de Cuidados Intensivos , Biomarcadores , Estudios Retrospectivos
13.
Materials (Basel) ; 15(20)2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36295354

RESUMEN

With the growing need for portable, compact, low-cost, and efficient biosensors, plasmonic materials hold the promise to meet this need owing to their label-free sensitivity and deep light-matter interaction that can go beyond the diffraction limit of light. In this review, we shed light on the main physical aspects of plasmonic interactions, highlight mainstream and future plasmonic materials including their merits and shortcomings, describe the backbone substrates for building plasmonic biosensors, and conclude with a brief discussion of the factors affecting plasmonic biosensing mechanisms. To do so, we first observe that 2D materials such as graphene and transition metal dichalcogenides play a major role in enhancing the sensitivity of nanoparticle-based plasmonic biosensors. Then, we identify that titanium nitride is a promising candidate for integrated applications with performance comparable to that of gold. Our study highlights the emerging role of polymer substrates in the design of future wearable and point-of-care devices. Finally, we summarize some technical and economic challenges that should be addressed for the mass adoption of plasmonic biosensors. We believe this review will be a guide in advancing the implementation of plasmonics-based integrated biosensors.

14.
Sensors (Basel) ; 22(14)2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35890942

RESUMEN

An alternative packaging method, termed built-in packaging, is proposed for single terminal devices, and demonstrated with an actuator application. Built-in packaging removes the requirements of wire bonding, chip carrier, PCB, probe station, interconnection elements, and even wires to drive single terminal devices. Reducing these needs simplifies operation and eliminates possible noise sources. A micro resonator device is fabricated and built-in packaged for demonstration with electrostatic actuation and optical measurement. Identical actuation performances are achieved with the most conventional packaging method, wire bonding. The proposed method offers a compact and cheap packaging for industrial and academic applications.

15.
Coron Artery Dis ; 33(6): 465-472, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35811509

RESUMEN

OBJECTIVE: COVID-19 pandemic continues to threaten human health as novel mutant variants emerge and disease severity ranges from asymptomatic to fatal. Thus, studies are needed to identify the patients with ICU need as well as those who have subsequent mortality. Global Registry of Acute Coronary Events (GRACE) risk score is a validated score in acute coronary syndrome. We aimed to evaluate if GRACE score can indicate adverse outcomes and major ischemic events in hospitalized COVID-19 patients. METHODS: All hospitalized patients due to COVID-19 at our institution between March 2020 and September 2020 were included in this retrospective study. Patients were grouped according to GRACE risk scores: low risk 0-108 points, intermediate risk 109-140 and high risk ≥141. RESULTS: A total of 787 patients were enrolled; 434 patients formed group 1. One-hundred forty-one patients in group 2 and 212 patients formed group 3. We found that inhospital mortality, length of hospital stay, ICU and advanced ventilatory support need were associated with increasing GRACE risk score. In addition, major ischemic events were more frequently observed in higher risk groups and strong positive correlations between GRACE risk score and pro-BNP, procalcitonin and moderate positive correlation with D-dimer, CRP, NLR was found. Regression analysis showed that only GRACE risk score was an independent risk factor associated with inhospital mortality, major ischemic events, advanced ventilatory support and ICU need. CONCLUSION: The GRACE risk score is easy to apply on hospital admission and useful for classifying those in medium-high-intensity care units and to raise the assignments of sources.


Asunto(s)
Síndrome Coronario Agudo , COVID-19 , Humanos , Pandemias , Pronóstico , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo
16.
Sensors (Basel) ; 22(11)2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35684724

RESUMEN

We report on the deployment of MEMS static bifurcation (DC) sensors for the detection of volatile organic compounds (VOCs): hydrogen sulfide and formaldehyde. We demonstrate a sensor that can detect as low as a few ppm of hydrogen sulfide. We also demonstrate a sensor array that can selectively detect formaldehyde in the presence of benzene, a closely related interferent. Toward that end, we investigate the sensitivity and selectivity of two detector polymers-polyaniline (PANI) and poly (2,5-dimethyl aniline) (P25DMA)-to both gases. A semiautomatic method is developed to functionalize individual sensors and sensor arrays with the detector polymers. We found that the sensor array can selectively sense 1 ppm of formaldehyde in the presence of benzene.


Asunto(s)
Sulfuro de Hidrógeno , Sistemas Microelectromecánicos , Compuestos Orgánicos Volátiles , Benceno , Formaldehído , Polímeros
17.
Nano Lett ; 22(8): 3196-3203, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35404606

RESUMEN

A resonant microcantilever sensor is fabricated from a zinc oxide (ZnO) thin film, which serves as both the structural and sensing layers. An open-air spatial atomic layer deposition technique is used to deposit the ZnO layer to achieve a ∼200 nm thickness, an order of magnitude lower than the thicknesses of conventional microcantilever sensors. The reduction in the number of layers, in the cantilever dimensions, and its overall lower mass lead to an ultrahigh sensitivity, demonstrated by detection of low humidity levels. A maximum sensitivity of 23649 ppm/% RH at 5.8% RH is observed, which is several orders of magnitude larger than those reported for other resonant humidity sensors. Furthermore, the ZnO cantilever sensor is self-actuated in air, an advantageous detection mode that enables simpler and lower-power-consumption sensors.


Asunto(s)
Óxido de Zinc , Humedad , Óxido de Zinc/química
18.
Blood Press Monit ; 27(2): 105-112, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34855651

RESUMEN

BACKGROUND: Perioperative hypertension is a frequent complication even in preoperatively normotensive or controlled hypertensive patients and there is a lack of data regarding the effect of nondipping pattern on perioperative hypertension. OBJECTIVE: In this study, we aimed to investigate the possible effect of nondipping blood pressure pattern on the risk of perioperative hypertension. MATERIALS AND METHODS: 234 hypertensive patients who underwent surgery with general anesthesia were evaluated prospectively. The study enrolled patients with well-controlled preoperative blood pressure. The 24-h ambulatory blood pressure monitoring results were used to classify patients as dippers and nondippers. Perioperative hypertension is defined as a systolic/diastolic arterial blood pressure greater than or equal to 160/90 mmHg or systolic blood pressure elevated by more than 20% from the patient's baseline level for more than 15 min perioperatively. RESULTS: There were 61 (26%) nondipper patients [mean age: 62.1 ± 7.1 years, 25 (40.9%) men] and 173 (74%) dipper patients [mean age: 61.4 ± 8.1 years, 83 (47.9%) men]. In the nondipper group, perioperative hypertension was observed in 31 (51.3%) patients, whereas in the dipper group, 33 (19.3%) patients experienced a hypertensive attack (P < 0.001). The independent predictors of perioperative hypertension were the presence of the nondipping pattern [odds ratio (OR) 3.084; 95% confidence interval (CI) 1.831-5.195; P < 0.001], the presence of diabetes mellitus (OR 2.059; 95% CI 1.215-3.490; P = 0.007), and the number of drugs (OR 2.317; 95% CI 1.102-5.097; P = 0.027). CONCLUSION: The frequency of perioperative hypertension was higher in preoperative normotensive and known hypertensive patients who were identified as nondippers. In addition, diabetes mellitus and number of drugs were found to be predictors of perioperative hypertension.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial , Hipertensión , Anciano , Presión Sanguínea/fisiología , Ritmo Circadiano/fisiología , Humanos , Masculino , Persona de Mediana Edad , Sístole
19.
Biomed Opt Express ; 13(11): 5643-5653, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36733742

RESUMEN

Optically shifting the focal plane to allow depth scanning of delicate biological structures and processes in their natural environment offers an appealing alternative to conventional mechanical scanning. Our technique uses a deformable mirror-based photoacoustic remote sensing microscopy (PARS) with a focus shifting of Δz ∼ 240 µm. We achieve this by integrating a deformable mirror that functions as a varifocal mirror for axial scanning. First, the system's focal shift capability was demonstrated with USAF resolution targets and carbon fiber phantoms, followed by in-vivo visualizations of blood vessels in chicken embryo chorioallantoic membrane (CAM). This work represents an initial step toward developing a non-contact, label-free, and aberration-free PARS imaging system with axial scanning capability.

20.
J Dairy Res ; 88(4): 461-467, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34866564

RESUMEN

In the burgeoning demand for optimization of cheese production, ascertaining cheese flavour formation during the cheese making process has been the focal point of determining cheese quality. In this research reflection, we have highlighted how valuable volatile organic compound (VOC) analysis has been in assessing contingent cheese flavour compounds arising from non-starter lactic acid bacteria (NSLAB) along with starter lactic acid bacteria (SLAB), and whether VOC analysis associated with other high-throughput data might help provide a better understanding the cheese flavour formation during cheese process. It is widely known that there is a keen interest to merge all omics data to find specific biomarkers and/or to assess aroma formation of cheese. Towards that end, results of VOC analysis have provided valuable insights into the cheese flavour profile. In this review, we are pinpointing the effective use of flavour compound analysis to perceive flavour-forming ability of microbial strains that are convenient for dairy production, intertwining microbiome and metabolome to unveil potential biomarkers that occur during cheese ripening. In doing so, we summarised the functionality and integration of aromatic compound analysis in cheese making and gave reflections on reconsidering what the role of flavour-based analysis might have in the future.


Asunto(s)
Queso , Lactobacillales , Compuestos Orgánicos Volátiles , Animales , Queso/análisis , Microbiología de Alimentos , Gusto , Compuestos Orgánicos Volátiles/análisis
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