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1.
BMC Cancer ; 24(1): 142, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287290

RESUMEN

BACKGROUND: The prognostic significance of mast cells and different phenotypes of macrophages in the microenvironment of hepatocellular carcinoma (HCC) following resection is unclear. We aimed in this study to assess the local distribution of infiltrating macrophages and mast cells of specific phenotypes in tissues of HCC and to evaluate their prognostic values for survival of post-surgical patients. METHODS: The clinicopathological and follow-up data of 70 patients with HCC, who underwent curative resection of tumor from 1997 to 2019, were collected. The infiltration of CD68+ and CD163+ macrophages and CD117+ mast cells was assessed immunohistochemically in representative resected specimens of HCC and adjacent tissues. The area fraction (AF) of positively stained cells was estimated automatically using QuPath image analysis software in several regions, such as tumor center (TC), inner margin (IM), outer margin (OM), and peritumor (PT) area. The prognostic significance of immune cells, individually and in associations, for time to recurrence (TTR), disease-free survival (DFS), and overall survival (OS) was evaluated using Kaplan-Meier and Cox regression analyses. RESULTS: High AF of CD68+ macrophages in TC and IM and high AF of mast cells in IM and PT area were associated with a longer DFS. High AF of CD163+ macrophages in PT area correlated with a shorter DFS. Patients from CD163TChigh & CD68TClow group had a shorter DFS compared to all the rest of the groups, and cases with CD163IMlow & CD68IMhigh demonstrated significantly longer DFS compared to low AF of both markers. Patients from CD68IMhigh & CD163PTlow group, CD117IMhigh & CD163PTlow group, and CD117PThigh & CD163PTlow group had a significantly longer DFS compared to all other combinations of respective cells. CONCLUSIONS: The individual prognostic impact of CD68+ and CD163+ macrophages and mast cells in the microenvironment of HCC after resection depends on their abundance and location, whereas the cumulative impact is built upon combination of different cell phenotypes within and between regions.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Pronóstico , Neoplasias Hepáticas/patología , Mastocitos/patología , Estimación de Kaplan-Meier , Macrófagos/patología , Microambiente Tumoral
2.
J Immunoassay Immunochem ; 44(4): 338-359, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37319429

RESUMEN

Several diagnostic measures have been employed to precisely detect the SARS-CoV-2 viral infection using viral antigens, nucleic acids, and other serological approaches. The sensitivity and specificity of the serological tests remain a challenging need. Here, we describe the detection of human anti-SARS-CoV-2 IgG and IgM antibodies qualitatively through two optimized in-house ELISA and lateral flow immunoassay. Both approaches are based on the prokaryotic expression of 50 kDa SARS-CoV-2 recombinant nucleocapsid protein. This SARS-CoV-2rN-6×His was used either to coat ELISA plates or to be conjugated to gold nanoparticles followed by colorimetric detection of bound human IgG or IgM. In the LFA, we show the optimization of nanoparticle size, protein-binding capacity, membrane treatment, and finally testing the potential capacity of using either the optimized ELISA or LFA in detecting antibodies raised against viral infection. Assessment of both methods was carried out using human sera-positive and negative SARS-CoV-2 antibodies. The ELISA and LFA tests showed 86%, 96.5% sensitivity, 92%, 93.75% specificity, 97%, 98.2% PPV, and 64%, 88.2% NPV, respectively. In conclusion, both approaches were able to successfully detect human antibodies against SARS-CoV-2 nucleocapsid protein. The importance of both protocols cannot be overstated in the detection and diagnosis of viral infections, especially in developing countries.


Asunto(s)
COVID-19 , Nanopartículas del Metal , Humanos , COVID-19/diagnóstico , Oro , Egipto , SARS-CoV-2 , Ensayo de Inmunoadsorción Enzimática/métodos , Sensibilidad y Especificidad , Inmunoglobulina G , Inmunoglobulina M , Anticuerpos Antivirales
3.
Sensors (Basel) ; 23(2)2023 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-36679506

RESUMEN

The article presents a Co-planar Waveguide (CPW) fed antenna of a low-profile, simple geometry, and compact size operating at the dual band for ISM and WLAN applications for 5G communication devices. The antenna has a small size of 30 mm × 18 mm × 0.79 mm and is realized using Rogers RT/Duroid 5880 substrate. The proposed dual-band antenna contains a CPW feedline along with the triangular patch. Later on, various stubs are loaded to obtain optimal results. The proposed antenna offers a dual band at 2.4 and 5.4 GHz while covering the impedance bandwidths of 2.25-2.8 GHz for ISM and 5.45-5.65 GHz for WLAN applications, respectively. The proposed antenna design is studied and analyzed using the Electromagnetic (EM) High-Frequency Structure Simulator (HFSSv9) tool, and a hardware prototype is fabricated to verify the simulated results. As the antenna is intended for on-body applications, therefore, Specific Absorption Rate (SAR) analysis is carried out to investigate the Electromagnetic effects of the antenna on the human body. Moreover, a comparison between the proposed dual-band antenna and other relevant works in the literature is presented. The results and comparison of the proposed work with other literary works validate that the proposed dual-band antenna is suitable for future 5G devices working in Industrial, Scientific, Medical (ISM), and Wireless Local Area Network (WLAN) bands.


Asunto(s)
Redes de Área Local , Tecnología Inalámbrica , Humanos , Diseño de Equipo , Comunicación
4.
Sensors (Basel) ; 23(2)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36679547

RESUMEN

In this manuscript, a compact in size yet geometrically simple Ultra-Wideband (UWB) antenna is demonstrated. The flexible-by-nature substrate ROGERS 5880, having a thickness of 0.254 mm, is utilized to design the proposed work. The antenna configuration is an excerpt of a traditional rectangular monopole antenna resonating at 5 GHz. Initially, a pair of triangular slots are employed to extend the impedance bandwidth of the antenna. In addition, a semi-circular-shaped, short-ended stub is connected at the upper edges of the patch to further increase the operational bandwidth. After optimization, the proposed antenna offers UWB ranging from 2.73-9.68 GHz, covering almost the entire spectrum allocated globally for UWB applications. Further, the antenna offers a compact size of 15 × 20 mm2 that can easily be integrated into small, flexible electronics. The flexibility analysis is done by bending the antenna on both the x and y axes. The antenna offers performance stability in terms of return loss, radiation pattern, and gain for both conformal and non-conformal conditions. Furthermore, the strong comparison between simulated and measured results for both rigid and bent cases of the antenna, along with the performance comparison with the state-of-the-art, makes it a potential candidate for present and future compact-sized flexible devices.


Asunto(s)
Electrónica , Tecnología Inalámbrica , Diseño de Equipo , Impedancia Eléctrica
5.
BMC Womens Health ; 22(1): 99, 2022 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-35361186

RESUMEN

OBJECTIVE: Facebook addiction is increasing, giving rise to limited real-life social networks, loneliness, poor work and academic performance, psychopathology, and low well-being. Facebook entails numerous factors that increase the risk for disordered eating attitudes and behaviors (e.g., use time and Facebook activities such as social grooming and photo sharing). This study aimed to evaluate the psychometric properties of the Bergen Facebook Addiction Scale (BFAS) among patients with eating disorders (EDs) given lack of validation of Facebook addiction measures in this population. METHODS: A cross-sectional study involving 123 inpatient and outpatient women with EDs (Mean age = 27.3, SD = 10.6, range = 14-59 years) used confirmatory factor analysis (CFA), multigroup CFA, structural equation modeling (SEM), Spearman's rho Spearman's analysis, McDonald's Omega (ω), Cronbach's alpha (α), and item-total correlations to examine the structure, invariance, criterion validity, reliability, and discriminant validity of the BFAS. RESULTS: Correlating the residuals of items 2, 3, and 5 resulted in an excellent fit of a one-factor structure of the BFAS (χ2(7) = 8.515, p = .289, CFI = .998, TLI = .996, RMSEA = .042, SRMR = .0099). The BFAS was invariant at the configural, metric, and scalar levels across groups of EDs, age, education, and marital status. High values of ω and α (.96) as well as item-total correlations (.851-.929) indicated excellent reliability and high discrimination index of the BFAS.  Criterion validity is noted by strong positive correlation with the Six-item Internet Addiction Test (S-IAT, r = .88) and SEM using the S-IAT to predict the BFAS (χ2(49) = 103.701, p = .001, CFI = .975, TLI = .966, RMSEA = .096, SRMR = .0317).. CONCLUSION: The BFAS is a reliable unidimensional measure. Its high discrimination index and invariance across different groups make it useful for detecting Facebook addiction among patients with ED.


Asunto(s)
Trastornos de Alimentación y de la Ingestión de Alimentos , Medios de Comunicación Sociales , Adolescente , Adulto , Estudios Transversales , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Femenino , Humanos , Persona de Mediana Edad , Psicometría , Reproducibilidad de los Resultados , Estudiantes , Adulto Joven
6.
Int J Mol Sci ; 23(23)2022 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-36499616

RESUMEN

Hepatocellular carcinoma (HCC) is a global healthcare challenge, which affects more than 815,000 new cases every year. Activated hepatic stellate cells (aHSCs) remain the principal cells that drive HCC onset and growth. aHSCs suppress the anti-tumor immune response through interaction with different immune cells. They also increase the deposition of the extracellular matrix proteins, challenging the reversion of fibrosis and increasing HCC growth and metastasis. Therapy for HCC was reported to activate HSCs, which could explain the low efficacy of current treatments. Conversely, recent studies aimed at the deactivation of HSCs show that they have been able to inhibit HCC growth. In this review article, we discuss the role of aHSCs in HCC pathophysiology and therapy. Finally, we provide suggestions for the experimental implementation of HSCs in HCC therapies.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Células Estrelladas Hepáticas/metabolismo , Neoplasias Hepáticas/metabolismo , Movimiento Celular , Línea Celular Tumoral
7.
Scand J Immunol ; 93(6): e13039, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33710663

RESUMEN

COVID-19 is highly transmissible; however, its severity varies from one individual to another. Variability among different isolates of the virus and among its receptor (ACE2) may contribute to this severity, but comorbidity plays a major role on disease prognosis. Many comorbidities have been reported to be associated with severe COVID-19 patients. We have collected data from retrospective studies which include clinical and epidemiological features of patients and categorize them into severe/mild, ICU/non-ICU and survivors/dead patients. In this review, we give an update about SARS-CoV-2 structure with emphasis on the possible reasons for the severity of the virus in patients. We also collected information and patients' data to highlight the relation between COVID-19 patients and comorbidities.


Asunto(s)
COVID-19/virología , Susceptibilidad a Enfermedades , SARS-CoV-2/fisiología , Biomarcadores , COVID-19/diagnóstico , COVID-19/inmunología , COVID-19/metabolismo , Comorbilidad , Citocinas/metabolismo , Manejo de la Enfermedad , Brotes de Enfermedades , Genoma Viral , Genómica/métodos , Interacciones Huésped-Patógeno/inmunología , Humanos , Mediadores de Inflamación/metabolismo , Pronóstico , Factores de Riesgo , Índice de Severidad de la Enfermedad
8.
Indian J Clin Biochem ; 34(2): 143-154, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31092987

RESUMEN

Firsthand and, to a lesser degree, secondhand tobacco smoking are considered the greatest causes of preventable illnesses and premature death worldwide. Firsthand and secondhand smoking have adverse consequences on the immune system, although these effects are not fully understood. A few serological studies have been done on firsthand and secondhand smokers in Saudi Arabia. The present study investigates the effects of firsthand and secondhand smoking on the immune system of randomly chosen male firsthand (50 subjects) and secondhand (50 subjects) cigarette smokers, residing in Jeddah, Saudi Arabia, with an age range of 20-40 years. Firsthand smokers were categorized according to the number of cigarettes smoked daily (frequency of smoking). Blood samples were collected and differential complete blood counts, cotinine concentrations, and antibodies (IgG, IgM, and IgA) concentrations were determined. Additionally, T, B, NK, CD4+ and CD8+ cells counts and percentages were determined. Compared to secondhand smokers, firsthand smokers showed a highly significantly higher mean cotinine concentration and a highly significantly lower mean IgA concentration. Additionally, Secondhand smokers had significantly higher mean lymphocyte count and CD4+/CD8+ ratio, and significantly lower mean basophil and NK cells counts. All other parameters showed no significant differences between firsthand and secondhand smokers and there were no differences between the frequency of smoking categories for the firsthand smokers. Therefore, The results show suggest that passive and active smoking have different immunological effects since IgA levels and some white blood cells counts were different in firsthand and secondhand smokers.

9.
Int J Biol Macromol ; 268(Pt 1): 131778, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38657929

RESUMEN

Ticks have harmful impacts on both human and animal health and cause considerable economic losses. Leucine aminopeptidase enzymes (LAP) play important roles during tick infestation to liberate vital amino acids necessary for growth. The aim of the current study is to identify, express and characterize the LAP from the hard tick Hyalomma dromedarii and elucidate its biochemical characteristics. We cloned an open reading frame of 1560 bp encoding a protein of 519 amino acids. The LAP full-length was expressed in Escherichia coli BL21 (DE3) and purified. The recombinant enzyme (H.d rLAP- 6×His) had a predicted molecular mass of approximately 55 kDa. Purification and the enzymatic characteristics of H.d rLAP- 6×His were studied. The purified enzyme showed maximum activity at 37 °C and pH 8.0-8.5 using Leu-p-nitroanilide as a substrate. The activity of H.d rLAP- 6×His was sensitive to ß-mercaptoethanol, dl-dithiothreitol, 1,10- phenanthroline, bestatin HCl, and EDTA and completely abolished by 0.05 % SDS. In parallel, the enzymatic activity was enhanced by Ni2+, Mn2+ and Mg2+, partially inhibited by Na+, Cu2+, Ca2+ and completely inhibited by Zn2+.


Asunto(s)
Secuencia de Aminoácidos , Clonación Molecular , Leucil Aminopeptidasa , Leucil Aminopeptidasa/química , Leucil Aminopeptidasa/metabolismo , Leucil Aminopeptidasa/genética , Animales , Especificidad por Sustrato , Concentración de Iones de Hidrógeno , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Cinética , Estabilidad de Enzimas , Temperatura , Filogenia , Ixodidae/enzimología , Ixodidae/genética
10.
Heliyon ; 10(1): e23711, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38192851

RESUMEN

A staircase-shaped quasi-fractal antenna is presented to meet the requirements of compact electronics operating in UWB or E-UWB spectrum. A conventional broadband monopole antenna is converted into UWB antenna utilizing three iterations of fractal patches. The resultant antenna offers wide impedance bandwidth ranges 2.3-17.8 GHz, having a notch band at 6.1-7.2 GHz. Afterwards, a two-port MIMO antenna is created by placing the second element orthogonally with an edge-to-edge distance of 8.5 mm, that is λ/15 where λ corresponds to free space wavelength at the lowest cut-off frequency. Hereafter, a meandered line-shaped stub is inserted to reduce the mutual coupling between closely spaced MIMO elements to less than -25 dB. As the intended application of the proposed work is On-body, Specific Absorption Rate (SAR) analyses are carried out at 2.4, 5.8 and 8 GHz, showing an acceptable range for both 1-g and 10-g averaged tissues standards. Moreover, various parameters of the MIMO antenna are studied, and a comparison is made between simulated and measured results as well as those of the state of the art.

11.
J Vis Exp ; (206)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38682951

RESUMEN

The insights provided by in-situ detection of immune cells within hepatocellular carcinoma (HCC) might present information on patient outcomes. Studies investigating the expression and localization of immune cells within tumor tissues are associated with several challenges, including a lack of precise annotation for tumor regions and random selection of microscopic fields of view. QuPath is an open-source, user-friendly software that could meet the growing need for digital pathology in whole-slide image (WSI) analysis. The infiltration of HCC and adjacent tissues by CD1a+ immature dendritic cells (iDCs), CD117+ mast cells, and NKp46+ natural killer cells (NKs) cells was assessed immunohistochemically in representative specimens of 67 patients with HCC who underwent curative resection. The area fraction (AF) of positively stained cells was assessed automatically in WSIs using QuPath in the tumor center (TC), inner margin (IM), outer margin (OM), and peritumor (PT) area. The prognostic significance of immune cells was evaluated for time to recurrence (TTR), disease-free survival (DFS), and overall survival (OS). The AF of mast cells was significantly greater than the AF of NKs, and the AF of iDCs was significantly lower compared to NKs in each region of interest. High AFs of mast cells in the IM and PT areas were associated with longer DFS. In addition, high AF of mast cells in IM was associated with longer OS. Computer-assisted analysis using this software is a suitable tool for obtaining prognostic information for tumor-infiltrating immune cells (iDCs, mast cells, and NKs) in different regions of HCC after resection. Mast cells displayed the greatest AF in all regions of interest (ROIs). Mast cells in the peritumor region and IM showed a positive prognostic significance.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Mastocitos , Programas Informáticos , Microambiente Tumoral , Humanos , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/cirugía , Mastocitos/patología , Mastocitos/inmunología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/cirugía , Estudios Retrospectivos , Pronóstico , Microambiente Tumoral/inmunología , Masculino , Persona de Mediana Edad , Procesamiento de Imagen Asistido por Computador/métodos , Femenino , Anciano
12.
Front Vet Sci ; 11: 1434627, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39170633

RESUMEN

Introduction: Leucocytozoon is an intracellular blood parasite that affects various bird species globally and is transmitted by blackfly vectors. This parasite is responsible for leucocytozoonosis, a disease that results in significant economic losses due to reduced meat and egg production. There is limited knowledge about the epidemiological pattern of leucocytozoonosis and its causative species in Egypt, particularly in pigeons. Methods: The current study involved the collection of 203 blood samples from domestic pigeons from various household breeders and local markets across Qena Province, Upper Egypt. Samples were initially examined for potential Leucocytozoon infection using blood smears, followed by an evaluation of associated risk factors. Molecular identification of the parasite in selected samples (n = 11), which had initially tested positive via blood smears, was further refined through nested PCR and sequence analysis of the mitochondrial cytochrome b gene to ascertain the Leucocytozoon species present. Additionally, histopathological examination of the liver, spleen, and pancreas was conducted on animals that tested positive by blood smears. Results: Interestingly, 26 out of 203 samples (12.08%) had confirmed Leucocytozoon infections based on microscopic analysis. Additionally, all 11 samples that initially tested positive via blood smears were confirmed positive through nested PCR analysis, and their sequencing revealed the presence of Leucocytozoon sabrazesi, marking the first report of this parasite in Egypt. The study into potential risk factors unveiled the prevalence of Leucocytozoon spp. seems host gender-dependent, with males exhibiting a significantly higher infection rate (33.33%). Additionally, adult birds demonstrated a significantly higher infection prevalence than squabs, suggesting an age-dependent trend in prevalence. Seasonality played a significant role, with the highest occurrence observed during summer (37.25%). Histopathological examination revealed the presence of numerous megaloschizonts accompanied by lymphocytic infiltration and multiple focal areas of ischemic necrosis. Conclusion: To our knowledge, this is the first study to shed light on the epidemiological characteristics and molecular characterization of leucocytozoonosis in pigeons in Egypt. Further research endeavors are warranted to curb the resurgence of Leucocytozoon parasites in other avian species across Egypt, thereby refining the epidemiological understanding of the disease for more effective control and prevention measures.

13.
Anal Methods ; 15(46): 6425-6434, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37969098

RESUMEN

A new optical sensor was developed for the rapid sensing of total phenolic content, which is simple, cheap, and sensitive, using the Eu(III)-(NTA)2-(Phen) complex [NTA = 1-(2-naphthoyl)-3,3,3-trifluoroacetone and Phen = 1,10 phenanthroline] as a luminescent probe at pH 7.5 using PIPES buffer. This method was based on luminescence quenching. The type of quenching during the reaction between the Eu(III)-(NTA)2-(Phen) complex and the phenolic compounds is dynamic quenching; the binding site is close to 1, and the reaction is endothermic, spontaneous, and involves hydrophobic attraction forces. The calibration curves were plotted using a sigmoidal fit giving an LOD of 0.01 µg mL-1, and the correlation coefficients are more than 0.99. For the first time, the time-resolved fluorescence technique was utilized in microtiter plates to enable the determination of 96 samples within two minutes with high sensitivity and selectivity. The proposed method was applied to three industrial wastewater samples and compared with the standard method for phenolic content determination, yielding high recoveries. This is the first luminescence method based on lanthanide complexes as probes for determining the total phenolic content in water samples.

14.
Ocul Immunol Inflamm ; 31(6): 1273-1278, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36737061

RESUMEN

COVID-19 vaccinations have been accompanied by reports of inflammatory uveitis. Herein, we report the first case of bilateral persistent placoid maculopathy (PPM) following COVID-19 vaccinations in a previously healthy 58-year-old man who presented with bilateral decrease in vision approximately 2 weeks after the second dose of AstraZenaca® ChAdOx1-S/nCoV-19 vaccine. Fundus examination revealed bilateral well-delineated whitish plaque-like macular lesions involving the fovea. Clinical and multimodal imaging findings were suggestive of PPM. Infective and autoimmune screen were all negative except for a raised MPO-ANCA. Medical review excluded systemic autoimmune and infectious diseases. Patient was monitored closely and his visual acuity improved and stabilised after a tapering regime of oral prednisolone. Mycophenolate mofetil was given as long-term steroid sparing immunosuppression. Our case demonstrated a likely localised autoimmune inflammatory response to the COVID-19 vaccine affecting choriocapillaris. Further research is needed to clarify the association between COVID-19 vaccines and inflammatory placoid lesions of the retina.


Asunto(s)
COVID-19 , Degeneración Macular , Enfermedades de la Retina , Masculino , Humanos , Persona de Mediana Edad , Vacunas contra la COVID-19/efectos adversos , Enfermedades de la Retina/inducido químicamente , Enfermedades de la Retina/diagnóstico , Angiografía con Fluoresceína/métodos , COVID-19/complicaciones
15.
Micromachines (Basel) ; 14(2)2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36838049

RESUMEN

Metamaterials exhibit properties in terms of subwavelength operation or phase manipulation, among others, that can be used in a variety of applications in 5G communication systems. The future and current 5G devices demand high efficiency, high data rate, computational capabilities, cost-effectiveness, compact size, and low power consumption. This variation and advancement are possible when the antenna design is revised to operate over wideband, high gain, and multiband and has characteristics of compact size, reconfiguration, absorption, and simple ease of fabrication. The materials loaded with antennas or, in the same cases, without antennas, offer the aforementioned characteristics to bring advancement in order to facilitate users. A number of works on designing metasurfaces capable of improving bandwidth, gain efficiency, and reducing the size and cost of antennas are available in the literature for this purpose. Not only are these applications possible, but the intelligent metasurfaces are also designed to obtain reconfiguration in terms of frequency and polarization. The number of absorbers loaded with metamaterials is also designed to improve the absorption percentage used for radar applications. Thus, in this paper, the general overview of different types of metamaterials and their role in performance enhancement and application in 5G and 6G communication systems is discussed.

16.
Heliyon ; 9(9): e19985, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809980

RESUMEN

The research paper discusses the detailed designing of a compact, simple, and low-profile antenna that provides several desirable features. The antenna is engineered by using a substrate material called Roger 6002, and its dimensions are 12 mm × 6 mm × 1.52 mm. The single antenna element achieves a wideband frequency coverage of 24-30.2 GHz and a high gain of 9 dBi. To enhance the antenna's capabilities, a two-port multiple-input multiple-output (MIMO) configuration is employed by adding a second antenna element orthogonal to the first one. Although the operational band remains the same, the isolation between the two elements is found to be unsatisfactory. A C-shaped decoupling structure is established to address this issue, which effectively improves the isolation. Including the parasitic patch enhances the isolation from -18 dB to -29 dB. An antenna hardware sample is built and tested to validate the recommended work, and the outcomes are compared to the predicted results obtained from the software. The experimental and simulated data exhibit close agreement, confirming the accuracy of the design. Additionally, this outstanding performance in bandwidth and isolation compares with existing literature, presented in the form of a table. Various MIMO parameters are also examined, and it is found that they fall within acceptable ranges. The antenna demonstrates an Envelope Correlation Coefficient (ECC) of approximately 0.005 and a Diversity Gain (DG) of around 9.99 dB. The recommended antenna design is highly suitable for future miniature devices used in Internet of Things (IoT) applications.

17.
Environ Sci Pollut Res Int ; 30(53): 113889-113902, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37858013

RESUMEN

Renewable energy systems are vital for a sustainable future, where solid-state hydrogen storage can play a crucial role. Perovskite hydride materials have attracted the scientific community for hydrogen storage applications. The current work focuses on the theoretical study using density functional theory (DFT) to evaluate the characteristics of MgXH3 (X = Co, Cu, Ni) hydrides. The structural, vibrational, electronic, mechanical, thermodynamic, and hydrogen storage properties of these hydrides were investigated. The equilibrium lattice parameters were calculated using the Birch-Murnaghan equation of state-to-energy volume curves. The elastic constants (Cij) and relevant parameters, such as Born criteria, were calculated to confirm the mechanical stability of the hydrides. The Cauchy pressure (Cp) revealed brittle or ductile behavior. The outcomes of the Pugh ratio, Poisson ratio, and anisotropy were also calculated and discussed. The absence of negative lattice vibrational frequencies in phonon dispersion confirmed the lattice's dynamic stability. The heat capacity curves of thermodynamic properties revealed that hydrides can conduct thermal energy. The metallic character and ample interatomic distances of hydrides were confirmed by the band structure and population analysis, which confirmed that hydrides can conduct electrical energy and adsorb hydrogen. The density of state (DOS) and partial DOS unveiled the role of specific atoms in the DOS of the crystal. The calculated gravimetric hydrogen storage capacity of MgCoH3, MgCuH3, and MgNiH3 hydrides was 3.64, 3.32, and 3.49wt%, respectively. Our results provide a deeper understanding of its potential for hydrogen storage applications through a detailed analysis of MgXH3 (X = Co, Cu, Ni) perovskite hydride material.


Asunto(s)
Compuestos de Calcio , Óxidos , Termodinámica , Hidrógeno
18.
Pathol Res Pract ; 244: 154411, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36921547

RESUMEN

Endometrial cancer (EC) is the 2nd common cancer in females after breast cancer. Besides, it's the most common among gynecological cancers. Several epigenetic factors such as miRNAs have been reported to affect EC aspects including initiation, progression, angiogenesis, and resistance to therapy. miRNAs could regulate the expression of various genes involved in EC pathogenesis. This effect is attributed to miRNAs' effects in proliferation, apoptosis, cell cycle, angiogenesis, invasion, and metastasis. miRNAs also influence crucial EC-related mechanistic pathways such as JAK/STAT axis, EGFR, TGF-ß signaling, and P53. Beside pathogenesis, miRNAs also have the potential to affect EC response to treatments including radio and chemotherapy. Thus, this review aims to illustrate the link between miRNAs and EC; focusing on the effects of miRNAs on EC signaling pathways.


Asunto(s)
Neoplasias de la Mama , Neoplasias Endometriales , MicroARNs , Femenino , Humanos , MicroARNs/metabolismo , Resistencia a Antineoplásicos/genética , Transducción de Señal/genética , Neoplasias Endometriales/genética , Neoplasias Endometriales/terapia , Neoplasias Endometriales/patología , Neoplasias de la Mama/genética , Regulación Neoplásica de la Expresión Génica/genética
19.
BMJ Case Rep ; 15(9)2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-36127035

RESUMEN

A young Asian man with a diagnosis of complex congenital heart disease and visceral situs inversus presented to the eye casualty with a recent onset of blurred vision in his left eye. Funduscopic examination of the left eye showed the presence of intraretinal haemorrhages in the inferior and superonasal quadrants, sparing the superotemporal arcade. Optical coherence tomography showed presence of macular oedema and fundus fluorescein angiography confirmed the diagnosis of central retinal vein occlusion sparing the superotemporal branch. Intravitreal antivascular endothelial growth factor treatment was administered, with favourable anatomic and functional outcomes. The presentation of an incomplete central retinal vein occlusion is extremely unusual, especially in a patient with significant cardiac malformation. With the current advances in interventional cardiac procedures, more patients are having longer lifespan and are presenting to ophthalmologists with ocular consequences of circulatory disorders, emphasising the need for multidisciplinary management.


Asunto(s)
Enfermedades Cardiovasculares , Edema Macular , Oclusión de la Vena Retiniana , Factores de Crecimiento Endotelial , Angiografía con Fluoresceína , Humanos , Masculino , Oclusión de la Vena Retiniana/diagnóstico , Oclusión de la Vena Retiniana/etiología
20.
Biomed Pharmacother ; 149: 112838, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35344738

RESUMEN

Diabetes is a metabolic disease that is mainly characterized by hyperglycemia. The present work investigated the efficacy of the flavanones hesperetin (HES) and quercetin (Q) extracted from Trifolium alexandrinum (TA) to treat type 2 diabetic rats. Wistar albino rats were supplemented with a high fat diet (HFD) for 2 weeks and then administered streptozotocin to induce diabetes. Diabetic rats were orally treated with Q, HES, and TA extract at concentrations of 40, 50, and 200 mg/kg BW, respectively, for 4 weeks. Various biochemical, molecular, and histological analysis were performed to evaluate the antidiabetic effects of these treatments. Q, HES, and TA extract treatments all significantly improved diabetic rats' levels of serum glucose, insulin, glucagon, liver function enzymes, hepatic glycogen, α-amylase, lipase enzymes, lipid profiles, oxidative stress indicators, and antioxidant enzymes as compared with control diabetic untreated rats. In addition, supplementation with Q, HES, and TA extract attenuated the activities of glucose-6-phosphate; fructose-1,6-bisphospahate; 6-phosphogluconate dehydrogenase; glucose-6-phosphate dehydrogenase; glucokinase; and hexokinase in pancreatic tissue, and they improved the levels of glucose transporter 2 and glucose transporter 4. Furthermore, these treatments modulated the expressions levels of insulin receptor (IR), phosphoinositide 3-kinase (PI3K), AMP-activated protein kinase (AMPK), caspase-3, and interleukin-1ß (IL-1ß). Enhancement of the histological alterations in pancreatic tissues provided further evidence of the ability of Q, HES, and TA extract to exert antidiabetic effects. Q, HES, and TA extract remedied insulin resistance by altering the IR/PI3K and AMPK signaling pathways, and they attenuated type 2 diabetes by improving the antioxidant defense system.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Trifolium , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Metabolismo de los Hidratos de Carbono , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Hesperidina , Hipoglucemiantes/metabolismo , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Insulina , Hígado , Fosfatidilinositol 3-Quinasas/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Quercetina/farmacología , Ratas , Ratas Wistar , Receptor de Insulina/metabolismo , Estreptozocina/farmacología , Trifolium/química , Trifolium/metabolismo
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