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1.
Vaccine X ; 18: 100495, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38746061

RESUMEN

Objective: Breakthrough COVID-19 infections are common following immunisation with various types of vaccines. The patterns of infections have not been well established. We aimed to analyse the signs and symptoms of post vaccination infections in addition to the need for hospital admission, ER visit and supplemental oxygen in relation to age and gender. Methods: A cross-sectional cohort study was conducted in JUH from March 2021 to August 2022, we interviewed 1479 individuals who are >15 years of age and got a breakthrough infection. The statistical analysis was performed using STATA statistical software. Results: Out of the 1479 cases, 50.2 % and 69.4 % were females and less than 45 years of age respectively. Symptoms of cough, fever and headache were reported by nearly 50 % of the patients, while one-third complained of dyspnoea. We found that participants older than 45 years had worse clinical outcomes (P-value < 0.001). 13 deaths were identified in this study due to breakthrough infection, 92.3 % of them were older than 45 years (P-value < 0.001). Participants ≥45 years who experienced a breakthrough infection of COVID-19 were 0.7 times less likely to be females using adjusted logistic regression. Conclusion: This study indicates that despite more severe symptoms reported in younger patients, the major clinical outcomes were worse among older patients, which makes age a major risk for poor outcomes regardless of symptoms. Thus, older people should be evaluated carefully when presenting with mild symptoms of COVID-19 breakthrough infection. The study also confirms that there is no difference in the incidence of COVID-19 breakthrough infections between males and females. Prospective studies are needed to risk stratify COVID-19 breakthrough infections, which should take into account variants of the virus and comorbidities.

2.
Front Immunol ; 15: 1375589, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38650929

RESUMEN

Ferroptosis is an emerging form of regulated cell death in an oxidative stress- and iron-dependent manner, primarily induced by the over-production of reactive oxygen species (ROS). Manipulation of ferroptosis has been considered a promising therapeutic approach to inhibit liver tumor growth. Nevertheless, the development of resistance to ferroptosis in liver cancer poses a significant challenge in cancer treatment. Post-translational modifications (PTMs) are crucial enzymatic catalytic reactions that covalently regulate protein conformation, stability and cellular activities. Additionally, PTMs play pivotal roles in various biological processes and divergent programmed cell death, including ferroptosis. Importantly, key PTMs regulators involved in ferroptosis have been identified as potential targets for cancer therapy. PTMs function of two proteins, SLC7A11, GPX4 involved in ferroptosis resistance have been extensively investigated in recent years. This review will summarize the roles of PTMs in ferroptosis-related proteins in hepatocellular carcinoma (HCC) treatment.


Asunto(s)
Carcinoma Hepatocelular , Ferroptosis , Neoplasias Hepáticas , Procesamiento Proteico-Postraduccional , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Animales , Especies Reactivas de Oxígeno/metabolismo , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Estrés Oxidativo
3.
Polymers (Basel) ; 16(8)2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38675079

RESUMEN

Ever-increasing electromagnetic pollution largely affects human health, sensitive electronic equipment, and even military security, but current strategies used for developing functional attenuation materials cannot be achieved in a facile and cost-effective way. Here, a unique core-shell-like composite was successfully synthesized by a simple chemical approach and a rapid microwave-assisted carbonization process. The obtained composites show exceptional electromagnetic wave absorption (EMWA) properties, including a wide effective absorption band (EAB) of 4.64 GHz and a minimum reflection loss (RLmin) of -26 dB at 1.6 mm. The excellent performance can be attributed to the synergistic effects of conductive loss, dielectric loss, magnetic loss, and multiple reflection loss within the graphene-based core-shell-like composite. This work demonstrates a convenient, rapid, eco-friendly, and cost-effective method for synthesizing high-performance microwave absorption materials (MAMs).

4.
OTO Open ; 8(1): e117, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38420352

RESUMEN

Objective: The impact of poor sleep on tinnitus has been mainly attributed to central processes. There is an association between sleep disorders and hearing loss, but whether hearing levels mediate the association between sleep disorders and tinnitus is unknown. This study investigates the association between sleep characteristics, tinnitus, and hearing loss. Study Design: Cross-sectional. Setting: National Health and Nutrition Examination Survey (NHANES). Methods: Study cohort includes 9693 adults (≥20 years) from the NHANES 2005 to 2018 who completed audiometric testing and questionnaires on tinnitus and sleep characteristics. Multivariable regression analyses were performed to quantify associations between sleep characteristics, tinnitus, and hearing loss. Results: In this cohort, 29% (95% confidence interval [CI]: 28%-31%) reported trouble sleeping and 9% (95% CI: 8%-10%) reported being diagnosed with sleep disorders. Negative sleep characteristics (less hours of sleep, diagnosis of a sleep disorder, trouble sleeping, or OSA symptoms) were not associated with audiometry-measured hearing loss in multivariable models adjusted for demographics and comorbidities but were significantly associated with bothersome tinnitus. This association remained significant without substantial attenuation in multivariable models additionally adjusting for hearing levels: sleeping <8 h/day (vs ≥8) (odds ratio [OR]: 1.28 [95% CI: 1.08-1.52]), trouble sleeping (OR: 1.78 [95% CI: 1.45-2.19]), diagnosis of sleep disorders (OR: 1.57 [95% CI: 1.14-2.15]), and report of OSA symptoms (OR: 1.42 [95% CI: 1.08-1.88]). Conclusion: Negative sleep characteristics were associated with tinnitus while there was no clinically meaningful association between sleep and hearing loss. Our findings suggest that the relationship between poor sleep and tinnitus is likely contributed by central processes without a major role of mediation via the peripheral auditory system.

5.
J Med Econ ; 27(1): 455-462, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38390791

RESUMEN

BACKGROUND AND PURPOSE: The incidence of end-stage renal disease (ESRD) in Sudan is increasing, affecting the economic status of patients, caregivers and society. This study aimed to measure ESRD's costs, including direct and morbidity indirect expenditures, and to investigate any associated factors and financial consequences. MATERIALS AND METHODS: This cross-sectional study used a standardized questionnaire to collect data from 150 ESRD patients who had been receiving dialysis for at least one year before the time of data collection at 13 specialized renal centres in Khartoum state. Data about sociodemographic, clinical, and economic factors were gathered, and their relationship to the cost of ESRD was examined using both bivariate (Man Whitney test, Kruskal Wallis test and Spearman correlation) and multivariate analytical procedures (multivariate linear regression). RESULTS: This study reported a median direct per capita ESRD cost of 38 600 SDG ($1 723.2 PPP) annually with an interquartile range of 69 319.3 SDG ($3 094.6 PPP). The median morbidity indirect cost was estimated to be 0.0 ± 3 352 SDG ($ 0.0 ± 149.6 PPP) per annum. In 28.8% of cases, the patients were their family's primary income earner and over 85% were covered by medical insurance. Our study found that none of the study variables were significantly associated with the total cost of ESRD. CONCLUSION AND LIMITATIONS: Our findings point out considerable direct out-of-pocket expenses and productivity losses for patients and their households. However, these results should be carefully applied for comparison between the different countries due to differences in the cost of medical interventions and insurance coverage. Further longitudinal studies and studies on health finance and insurance policies are recommended.


As medical care costs continue to rise in Sudan, this study aimed to estimate direct and indirect costs associated with end-stage renal disease (ESRD) from the patient's perspective. Accurate information on the cost of illness (COI) helps policymakers prioritize healthcare services and resources, optimize public well-being, and determine health policy effectiveness. Future research should include a longitudinal design and understand ESRD costs from caregivers' and healthcare providers' perspectives.


Asunto(s)
Fallo Renal Crónico , Masculino , Humanos , Estudios Transversales , Fallo Renal Crónico/terapia , Diálisis Renal , Gastos en Salud , Costo de Enfermedad
6.
Laryngoscope ; 134(1): 393-396, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37289065

RESUMEN

OBJECTIVE: There is increased confusion regarding MRI-compatible CIs and BAHAs. This report describes two cases when patients underwent MRIs with non-MRI compatible devices. RESULTS: One patient with bilateral Cochlear Osias experienced dislocation of both internal magnets after 1.5 Tesla MRI. Both magnets were outside the silastic sheath, with the left magnet flipped. A second patient with a legacy CI experienced similar internal magnet dislocation and inversion after 3 Tesla MRI. CONCLUSIONS: This study describes internal magnet dislocation/inversion with the Cochlear Osia and a legacy CI after MRI. Our findings suggest the need for improved patient education and simplified radiology guidelines. Laryngoscope, 134:393-396, 2024.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Humanos , Implantación Coclear/efectos adversos , Imagen por Resonancia Magnética/métodos , Imanes , Tecnología
7.
Infect Drug Resist ; 16: 5985-6004, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37705514

RESUMEN

Background: Extreme body mass index (BMI) is an influential pathophysiological risk factor for serious illnesses following lower respiratory tract infection. The purpose of the current study was to examine how the BMI of Coronavirus disease-19 (COVID-19) patients affects their prognosis. Methods: Two hundred patients with COVID-19 admitted to Al-Azhar, Qena, Aswan, and Sohag University hospitals in Egypt were included and categorized into four groups according to their BMI. The diagnosis was made according to a real-time reverse transcription-polymerase chain reaction (rRT-PCR) positive result for the SARS-CoV-2 nucleic acid in swabs from upper respiratory tract. A detailed history, clinical examination, and outcomes (disease severity and complications, hospital stay, ICU admission, mortality) were recorded for all patients. SPSS version 24 software was used for data analysis. Results: Average age of participants (19-90 years old), 92 (46%) males and 108 females (54%). ICU admission was significantly higher among underweight patients (75%) and obese patients (78.6%). The majority of underweight (62.5%) and obese (57.1%) patients had critical disease. Invasive mechanical ventilation (MV) is frequently used in underweight (50%) and obese patients (42.9%) patients. Adult respiratory distress syndrome (ARDS), cardiac, neurological, and hematological complications, and incidence of myalgia and bed sores were most frequent among obese and overweight patients. Acute kidney injury was significantly higher among underweight patients (37.5%) and obese patients (28.6%) than among other classes (p=0.004). Frequency of endocrine complications was significantly higher in underweight patients than that in other classes (p=0.01). The majority of underweight (75%) and obese patients (50%) deteriorated and died, whereas the majority of normal-weight patients (90.3%) and overweight patients (75.8%) improved and were discharged (p< 0.001). Conclusion: Body mass index is a major contributing factor to the outcome of patients with COVID-19, and patients with extreme of body mass index were associated with the worst prognosis.

8.
J Voice ; 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37019804

RESUMEN

PURPOSE: The purpose of this study was to assess the relationship and comparability of cepstral and spectral measures of voice obtained from a high-cost "flat" microphone and precision sound level meter (SLM) vs. high-end and entry level models of commonly and currently used smartphones (iPhone i12 and iSE; Samsung s21 and s9 smartphones). Device comparisons were also conducted in different settings (sound-treated booth vs. typical "quiet" office room) and at different mouth-to-microphone distances (15 and 30 cm). METHODS: The SLM and smartphone devices were used to record a series of speech and vowel samples from a prerecorded diverse set of 24 speakers representing a wide range of sex, age, fundamental frequency (F0), and voice quality types. Recordings were analyzed for the following measures: smoothed cepstral peak prominence (CPP in dB); the low vs high spectral ratio (L/H Ratio in dB); and the Cepstral Spectral Index of Dysphonia (CSID). RESULTS: A strong device effect was observed for L/H Ratio (dB) in both vowel and sentence contexts and for CSID in the sentence context. In contrast, device had a weak effect on CPP (dB), regardless of context. Recording distance was observed to have a small-to-moderate effect on measures of CPP and CSID but had a negligible effect on L/H Ratio. With the exception of L/H Ratio in the vowel context, setting was observed to have a strong effect on all three measures. While these aforementioned effects resulted in significant differences between measures obtained with SLM vs. smartphone devices, the intercorrelations of the measurements were extremely strong (r's > 0.90), indicating that all devices were able to capture the range of voice characteristics represented in the voice sample corpus. Regression modeling showed that acoustic measurements obtained from smartphone recordings could be successfully converted to comparable measurements obtained by a "gold standard" (precision SLM recordings conducted in a sound-treated booth at 15 cm) with small degrees of error. CONCLUSIONS: These findings indicate that a variety of commonly available modern smartphones can be used to collect high quality voice recordings usable for informative acoustic analysis. While device, setting, and distance can have significant effects on acoustic measurements, these effects are predictable and can be accounted for using regression modeling.

9.
PLoS One ; 16(12): e0260857, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34882728

RESUMEN

HPV infection results in changes in host gene methylation which, in turn, are thought to contribute to the neoplastic progression of HPV-associated cancers. The objective of this study was to identify joint and disease-specific genome-wide methylation changes in anal and cervical cancer as well as changes in high-grade pre-neoplastic lesions. Formalin-fixed paraffin-embedded (FFPE) anal tissues (n = 143; 99% HPV+) and fresh frozen cervical tissues (n = 28; 100% HPV+) underwent microdissection, DNA extraction, HPV genotyping, bisulfite modification, DNA restoration (FFPE) and analysis by the Illumina HumanMethylation450 Array. Differentially methylated regions (DMR; t test q<0.01, 3 consecutive significant CpG probes and mean Δß methylation value>0.3) were compared between normal and cancer specimens in partial least squares (PLS) models and then used to classify anal or cervical intraepithelial neoplasia-3 (AIN3/CIN3). In AC, an 84-gene PLS signature (355 significant probes) differentiated normal anal mucosa (NM; n = 9) from AC (n = 121) while a 36-gene PLS signature (173 significant probes) differentiated normal cervical epithelium (n = 10) from CC (n = 9). The CC progression signature was validated using three independent publicly available datasets (n = 424 cases). The AC and CC progression PLS signatures were interchangeable in segregating normal, AIN3/CIN3 and AC and CC and were found to include 17 common overlapping hypermethylated genes. Moreover, these signatures segregated AIN3/CIN3 lesions similarly into cancer-like and normal-like categories. Distinct methylation changes occur across the genome during the progression of AC and CC with overall similar profiles and add to the evidence suggesting that HPV-driven oncogenesis may result in similar non-random methylomic events. Our findings may lead to identification of potential epigenetic drivers of HPV-associated cancers and also, of potential markers to identify higher risk pre-cancerous lesions.


Asunto(s)
Neoplasias del Ano/patología , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/patología , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Genoma Humano , Neoplasias del Cuello Uterino/patología , Adulto , Anciano , Neoplasias del Ano/genética , Neoplasias del Ano/terapia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Quimioradioterapia/métodos , Ensayos Clínicos Fase III como Asunto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Tasa de Supervivencia , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/terapia , Adulto Joven
10.
Radiol Case Rep ; 16(7): 1700-1707, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34007387

RESUMEN

Familial Mediterranean Fever (FMF) is an autosomal recessive disorder that is characterised by recurrent attacks of fever and painful polyserositis mainly affecting the peritoneum, synovium and pleura that usually begins in childhood. Even though diagnostic criteria have been proposed, conclusive imaging findings or haematological markers for the diagnosis or follow-up of FMF are still lacking. In this case report we present the 18F-FDG PET-CT findings in a 55 year old female during an attack of FMF. We briefly discuss the added value of 18F-FDG PET-CT in the diagnosis and the work-up of FMF, which may open up new applications for 18F-FDG PET-CT in non-infectious inflammatory diseases.

11.
ACS Appl Mater Interfaces ; 12(17): 19965-19973, 2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32275380

RESUMEN

At present, pressure sensor textiles are of great significance in the area of wearable electronics, especially for making smart or intelligent textiles. However, the design of these textile-based devices with sensitive ability, simple fabrication, and low cost is still challenging. In this study, we developed a triboelectric sensing textile constructed with core-shell yarns. Nylon filament and polytetrafluoroethylene filament were selected as the positive and negative layers, respectively, in the woven structure while the built-in helical stainless steel yarn was serving as the inner electrode layer. The sensitivity of the sensing textile can reach up to 1.33 V·kPa-1 and 0.32 V·kPa-1 in the pressure range of 1.95-3.13 kPa and 3.20-4.61 kPa, respectively. This sensing textile presented good mechanical stability and sensing capability even after 4200 cycles of continuous operation or after 4 h continuous water washing. Benefiting from the favorable merits of being highly flexible, breathable, lightweight, and even dyeable, the fabricated device was capable of being placed on any desired body parts for quantifying the dynamic human motions. It can be effectively used to measure and monitor various human movements associated with different joints, such as the hand, elbow, knee, and underarm. Moreover, the sensing textile was able to capture real-time pulse signals and reflect the current health status for human beings. This study affords an innovative and promising track for multifunctional pressure sensor textiles with wide applications in smart textiles and personalized healthcare.


Asunto(s)
Monitoreo Fisiológico/instrumentación , Movimiento , Pulso Arterial , Textiles , Dispositivos Electrónicos Vestibles , Electrodos , Humanos , Nylons/química , Politetrafluoroetileno/química , Acero Inoxidable/química
12.
Contemp Clin Trials ; 91: 105991, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32184197

RESUMEN

Lung cancer screening with low-dose computed tomography (LDCT) reduces lung cancer mortality, yet few eligible high-risk patients receive it annually. This protocol describes a community-partnered intervention (Toolkit) designed to support primary care practices in making referrals for lung screening and guiding patients into appropriate screening pathways. This study uses a stepped-wedge implementation design. Screening centers are randomized by readiness level to enter the intervention phase in three-month "steps" with pre-intervention data serving as the control. The primary outcome is whether delivery of the Toolkit to primary care practices results in a monthly increase in number of initial LDCT screenings. Six participating centers will identify 10 practices and reach 2-3 providers per practice to train them to use the Toolkit. The Toolkit will address known barriers to screening and referral at the patient and provider levels and provide support for required elements of screening. Toolkit components include adaptable evidence-based interventions to maximize compatibility with workflows. We hypothesize that after nine months of intervention delivery, the number of initial screening per center will double. Involving 60 practices achieves 80% power at 5% level of significance. Implementation outcomes such as adoption, acceptability, feasibility, adaptation, and sustainability will be assessed through field-notes and activity logs. LDCT for lung cancer screening currently reaches a small fraction of eligible adults. To reach the full potential to reduce mortality, primary care practices are an important venue for increasing appropriate referrals. This multidisciplinary trial will encourage acceptability and sustainability by using local knowledge and promoting partnership between providers and patients. Trial registration: ClinicalTrials.gov, NCT03958253.


Asunto(s)
Detección Precoz del Cáncer/métodos , Neoplasias Pulmonares/diagnóstico , Atención Primaria de Salud/organización & administración , Humanos , Capacitación en Servicio , Neoplasias Pulmonares/diagnóstico por imagen , Derivación y Consulta , Tomografía Computarizada por Rayos X
13.
ACS Appl Mater Interfaces ; 12(1): 1597-1605, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31840486

RESUMEN

Nowadays, real-time human motion sensing and pulse monitoring can provide significant basis for health assessment and medical diagnosis. Nevertheless, it is still a big challenge to design a lightweight, flexible, and energy-sustainable pressure sensor with high sensitivity and breathability. Here, we fabricated a triboelectric all-fiber structured pressure sensor via a facile electrospinning technique. The constructed sensor textile holds a composite structure made up of a polyvinylidene fluoride/Ag nanowire nanofibrous membrane (NFM), an ethyl cellulose NFM, and two layers of conductive fabrics. This wearable device with high shape adaptability exhibited excellent sensing capability because of the introduced hierarchically rough structure on the nanofibers. The sensitivity can reach up to 1.67 and 0.20 V·kPa-1 in the pressure range of 0-3 and 3-32 kPa, respectively. The fabricated sensor textile also showed a superior mechanical stability even after continuous operation of 7200 working cycles. This sensor textile was easily conformable on different desired body parts for dynamic motion sensing and real-time pulse monitoring. It can work in a self-powered manner to detect and quantify various human motions associated with joints, such as elbows, knees, and ankles. Additionally, it can be placed on the carotid artery to capture the pulse signals, serving as a reliable way to reflect the state of health. This work has great possibilities to promote the rapid advancement and broad applications of multifunctional pressure sensors and next-generation wearable electronics.


Asunto(s)
Técnicas Biosensibles , Monitores de Presión Sanguínea , Monitoreo Fisiológico/instrumentación , Textiles , Grafito/química , Humanos , Nanofibras/química , Pulso Arterial , Dispositivos Electrónicos Vestibles
14.
Biomed Res Int ; 2019: 2757450, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31886191

RESUMEN

BACKGROUND: Parvovirus B19 (B19 V) infection had been reported to be more frequent with serious clinical outcomes in patients with sickle cell disease (SCD) than in the general population. There is a wide variation in data among the existing literature regarding the seroprevalence of B19 V in patients with SCD. These data require further summary and analyses for better accuracy. This systematic review and meta-analysis was done to estimate the seroprevalence of B19 V in patients with SCD. METHODS: This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The databases of MEDLINE/PubMed, Virtual Health Library (VHL), ScienceDirect, Google Scholar, and OpenGrey were used for the systematic search. The random-effects model was used to estimate the pooled prevalence with the corresponding 95% confidence interval (CI) using OpenMeta Analyst software. Publication bias was estimated based on Begg's test, Egger's test, and examination of the funnel plot. Subgroup analyses and metaregression were used to explore the moderators of heterogeneity between studies. RESULTS: A total of 18 studies including 2890 patients were analyzed. The overall IgG seroprevalence of B19 V infection among patients with SCD was found to be 48.8% (95% CI 39.5%-58.0%). Evidence of publication bias was not detected. Evidence of acute viral infection detected by positive IgM antibodies among the screened SCD patients was found in 8.30% (95% CI 5.20%-11.4%) of them. There was a statistically significant association between seroprevalence of B19 V and geographical areas. CONCLUSION: There was a high prevalence of B19 V in patients with SCD. Healthcare providers need to be aware of the magnitude of B19 V infection in patients with SCD to ensure effective management. This review could provide a comprehensive view of B19 V prevalence in this susceptible population.


Asunto(s)
Anemia de Células Falciformes/sangre , Anticuerpos Antivirales/sangre , Eritema Infeccioso/sangre , Estudios Seroepidemiológicos , Anemia de Células Falciformes/inmunología , Anemia de Células Falciformes/patología , Anemia de Células Falciformes/virología , Anticuerpos Antivirales/inmunología , Eritema Infeccioso/inmunología , Eritema Infeccioso/patología , Eritema Infeccioso/virología , Humanos , Parvovirus B19 Humano/inmunología , Parvovirus B19 Humano/patogenicidad
15.
Methods Enzymol ; 626: 375-406, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31606083

RESUMEN

Tyrosine kinases are important for many cellular processes and disruption of their regulation is a factor in diseases like cancer, therefore they are a major target of anticancer drugs. There are many ways to measure tyrosine kinase activity in cells by monitoring endogenous substrate phosphorylation, or by using peptide substrates and incubating them with cell lysates containing active kinases. However, most of these strategies rely on antibodies and/or are limited in how accurately they model the intracellular environment. In cases in which activity needs to be measured in cells, but endogenous substrates are not known and/or suitable phosphospecific antibodies are not available, cell-deliverable peptide substrates can be an alternative and can provide information on activation and inhibition of kinases in intact, live cells. In this chapter, we review this methodology and provide a protocol for measuring Abl kinase activity in human cells using enzyme-linked immunosorbent assay (ELISA) with a generic antiphosphotyrosine antibody for detection.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Tirosina/metabolismo , Humanos , Células K562 , Fosforilación , Proteínas Proto-Oncogénicas c-abl/metabolismo , Especificidad por Sustrato
16.
RSC Adv ; 9(4): 1814-1821, 2019 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35516136

RESUMEN

To understand the influence of the construction of pH-responsive glycopolymer carriers on loading and release behaviors of the drug, three types of block glycopolymers with similar compositions but different constructions, PEG-b-P(DEA-co-GAMA), PEG-b-PDEA-b-PGAMA and PEG-b-PGAMA-b-PDEA, were successfully synthesized via atom transfer radical polymerization (ATRP) method. The compositions and structures of the three glycopolymers were characterized using 1H NMR (nuclear magnetic resonance) and GPC (gel permeation chromatography), while the morphology and size of aggregates from pH-sensitive block glycopolymers were measured using TEM (transmission electron microscopy) and DLS (dynamic light scattering). The results indicated that the micelles prepared from PEG-b-PGAMA-b-PDEA had a more compact shell structure. The drug-loaded micelles were prepared using the diafiltration method at pH 10, and the loading content and loading efficiency were analyzed using a UV-visible spectrophotometer. DOX-loaded micelles formed by PEG-b-PGAMA-b-PDEA with the more compact shell construction showed the highest loading content and loading efficiency (12.0 wt% and 58.0%) compared with the other two micelles. Moreover, the DOX release tests of these micelles were carried out under two PBS conditions (pH 7.4 and pH 5.5), and the DOX release amount in a certain time was analyzed using a UV-visible spectrophotometer. The results showed that the more compact shell construction of the three layered micelle obstructed the diffusion of a proton into the PDEA core at pH 5.5 and delayed the drug from releasing under both conditions. Moreover the two-layered micelle with a PDEA and PGAMA mixed core showed a relatively high release amount owing to the porous core permitting unimpeded releasing at pH 7.4 and promoted the protonation of PDEA at pH 5.5. Insights gained from this study show that the structure of block copolymers, leading to different constructions of micelles, could adjust the drug loading and release behavior to certain extent, thus it may contribute to improving the design of desirable drug delivery systems.

17.
ACS Appl Mater Interfaces ; 10(51): 44561-44569, 2018 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-30484305

RESUMEN

With the fast advancement of up-to-date communication technologies, electromagnetic wave (EMW) absorption materials are widely required for various applications. However, it is still a big challenge to produce lightweight, flexible, and high-efficiency EMW absorption materials in a broad-ranging frequency. Herein, we designed to fabricate the magnetic and dielectric nanofibrous membranes which can be effectively used as EMW absorption materials by facile electrospinning process. The as-fabricated composite carbon nanofibers (CNFs), which combined the components of nickel, cobalt antioxidant nanoparticles, and carbon nanotubes, exhibited outstanding magnetic and dielectric properties and strong absorption ability in a wide frequency range. These nanoparticles encapsulated in CNFs are extremely beneficial to the electrical conductivity of the composites through decreasing the contact loss within the CNFs by formation of the metal-metal interfaces. Correspondingly, the RL value of -46.60 dB was reached at 4.88 GHz frequency range with a layer thickness of 5.5 mm for these mechanically light and flexible membranes. The enhanced absorption performance (<-10 dB) in the wide frequency band (4.16-18 GHz) can be achieved by selecting a suitable thickness of the material. Results demonstrate that the permittivity and permeability of developed samples have been largely improved because of the integrated interaction of all introduced components in the structure. The composite membranes are a promising candidate for scalable, lightweight, and high-performance EMW absorption materials in the frequency range from C band to Ku band (4-18 GHz).

18.
Sci Rep ; 8(1): 12402, 2018 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-30120335

RESUMEN

Electromagnetic (EM) wave absorbing materials have been fabricated from diverse materials such as conductive polymers, carbon based nanostructures and magnetic metal oxides. Nevertheless, it has remained a great challenge to develop lightweight and high-efficiency EM wave absorbing materials with a broad frequency range. Herein, we report a scalable strategy to create Co3O4/carbon composite nanofibrous membrane by electrospinning technique followed by stabilization and carbonization processes. An optimal reflection loss (RL) value of 36.27 dB is reached at 13.76 GHz for a layer of 2 mm thickness. RL exceeding -20 dB can be realized in any interval within the 4.5-14.4 GHz range by selecting a proper thickness of the absorbing layer between 1 and 5 mm. The Co3O4/carbon composite nanofibrous membrane could be well served as promising and attractive candidates for lightweight and enhanced EM wave absorbing materials. This presented research provides an innovative and effective approach to design the novel EM wave absorbing material in a broad frequency range for practical applications.

19.
Cardiovasc Toxicol ; 18(1): 9-23, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28439707

RESUMEN

Several researchers studied the protective effect of the N-acetylcysteine (NAC) when it was given before the induction of myocardial infarction (MI). Other researchers studied such protective effect when it was before done and after done of the MI. The missing data are the comparison between the protective effect of NAC before myocardial injury with its protective effect both before and after myocardial injury. The aim of the study was to compare the cardioprotective effect of NAC on the isoprenaline-induced myocardial injury before the isoprenaline (ISP) injection with its protective effect both before and after the ISP injection. This study was applied over both short and long time periods. A total of 90 male adult Wistar albino rats were used in the study. The rats were divided into four groups: control group, ISP-treated group, NAC-pretreated group and NAC-pre-& posttreated group. Based on the duration of the experiment, the second and third groups were further subdivided into a and b groups. Histological, immunohistochemical and histomorphometric analysis were used. The myocytes in the ISP-treated groups were fragmented, disrupted with karyolysis. The blood vessels were dilated, congested and associated with blood extravasation, interstitial edema and cellular inflammatory infiltration. Much improvement was observed in the NAC-pretreated group. Focal degeneration was detected in the muscle fibers. The capillaries were normal. Minimal blood extravasation and cellular infiltration were seen. The cardiac muscle fibers in the NAC-pre-& posttreated group were regularly arranged. The mean collagen fiber area percent of the ISP-treated groups was significantly higher by 8.3-folds and 10.1-folds as compared with that of the control group and was also higher by 5.5-folds and 6.8-folds as compared with that of the NAC-pre-&posttreated groups. The α-SMA area percent in the ISP-treated groups was significantly higher by 12.2-folds and 23.9-folds as compared with that of the control group and was higher by 7.5-folds and 15-folds as compared with that of the NAC-pre-& posttreated groups. The mean PCNA area percent of the ISP-treated groups was significantly higher by 126.2 and 164.8% as compared with that of the control group and was higher by 106.3 and 141.5% as compared with that of NAC-pre-& posttreated groups. ISP had deleterious effects on the heart. Administration of NAC before ISP injection could largely reduce the ISP-induced short- and long-term alterations. The protection was maximum with the use of NAC before the ISP injection and continued after the injection for 12 days.


Asunto(s)
Acetilcisteína/farmacología , Inmunohistoquímica , Isoproterenol , Infarto del Miocardio/prevención & control , Miocitos Cardíacos/efectos de los fármacos , Actinas/metabolismo , Animales , Colágeno/metabolismo , Citoprotección , Modelos Animales de Enfermedad , Masculino , Infarto del Miocardio/inducido químicamente , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/ultraestructura , Antígeno Nuclear de Célula en Proliferación/metabolismo , Ratas Wistar , Factores de Tiempo
20.
Brachytherapy ; 14(5): 686-91, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26014645

RESUMEN

PURPOSE: Radioactive seed implants are widely used to treat cancer patients, most commonly those with prostate cancer. However, the seeds have a tendency to migrate after placement in patients, a phenomenon that can result in unfavorable outcomes. The ability of the seed strand to migrate was investigated by examining the impact of the strand surface on the velocity of its movement inside oil and gel media. METHODS AND MATERIALS: We investigated the motion of smooth surface strands and strands with different grooved helical profiles after they were placed in oil and gel media. Three patterns of grooved helices were studied (60, 140, and 300 rotations per meter). The movement of the strands through a tube filled with the medium was recorded by the motion sensor, and the drag forces on the individual strands were calculated and compared for the oil and gel media. RESULTS: The strands with 60, 140, and 300 rotations/meter grooved helical surfaces demonstrated less mobility in both oil and gel than the strands with a smooth surface. The strand with the highest number of helical grooves per meter recorded the largest drag force and moved more slowly in both media. CONCLUSIONS: The differential in the motion of the smooth strand and the strands with grooved surfaces can be attributed to the increased surface area of the grooved strands. This finding is significant since it will impact, theoretically, the design, and thus the migration of seed implants that are used to treat cancer patients, particularly those with prostate cancer.


Asunto(s)
Braquiterapia/instrumentación , Falla de Prótesis , Propiedades de Superficie , Braquiterapia/efectos adversos , Geles , Movimiento (Física) , Aceites , Prótesis e Implantes , Diseño de Prótesis
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