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1.
ACS Omega ; 9(8): 8763-8772, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38434870

RESUMEN

Two-dimensional (2D) materials such as MXenes have attracted considerable attention owing to their enormous potential for structural flexibility. Here, we prepared a Mo2TiC2Tx-layered structure from parent Mo2TiAlC2Tx MAX by chemically selective etching of the aluminum layer. The prepared MXene was employed in composite formation with CTAB-grafted multiwalled carbon nanotubes (MWCNTs) to have a structure with improved electrochemical performance. The samples were characterized to analyze the structure, morphology, elemental detection, vibrational modes, and surface chemistry, followed by an electrochemical performance of the Mo2TiC2Tx MXene and MWCNTs@Mo2TiC2Tx composite using the GAMRAY Potentiostat under a 1 M KOH electrolyte. The specific capacitance of pristine Mo2TiC2Tx was 425 F g-1, which was enhanced to 1740 F g-1 (almost 4 times) at 5 mV s-1 due to the increase in active surface area and conductive paths between the MXene sheets. The charge storage mechanism was studied by further resolving the cyclic voltammograms. MWCNTs@Mo2TiC2Tx showed much improved electrochemical performance and reaction kinetics, making it an ideal material candidate for supercapacitor applications.

2.
J Public Health Res ; 13(1): 22799036241231542, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38343398

RESUMEN

Background: Understanding of public awareness on public health issues is very crucial, including the current health crisis of COVID-19. This research aimed to examine the Knowledge, Attitudes and Practices among Students towards COVID-19. Design and methods: A cross-sectional survey was conducted among secondary school students in grades 10-12. Proportional sample allocation was used in 16 randomly selected schools. Moreover, the schools were recruited by using a systematic random sampling technique. Socio-demographic data and questions of the knowledge, attitude and practice were collected by interview. Logistic regression analyses were employed to identify the associated factors and p-value < 0.05 was considered statistically significant. Results: Among the 357 participants the level of good knowledge, positive attitude, and optimal practice were 65.2%, 66.7% and 89.4% respectively. Regression analyses showed that being in the adolescent age group (15-16 years old), living with >5 family size, and family with a good income effectively predicted knowledge level. Attitudes towards COVID-19, male students were pessimistic about COVID-19 prevention and control measures as opposed to their female counterparts [aOR = 0.39; 95% CI: 0.21-0.71). Students with awareness of the virus demonstrated greater (two-fold) odds of a positive attitude as opposed to their less-conscious counterparts. The urban-area male students were demonstrated a higher (three-fold) odds of good practice level towards COVID-19 prevention and control measures as opposed to their rural-area female counterparts. Conclusion: A good knowledge level denoted a positive attitude despite the lack of information. Meanwhile, good preventive measure practices and behaviours reflected high levels.

5.
J Investig Med High Impact Case Rep ; 10: 23247096221141190, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36458807

RESUMEN

Soft tissue sarcomas (STS) comprise a large group of heterogeneous malignant tumors that form approximately 1% of all adult malignancies. Most sarcomas originate from soft tissue and the rest arise from the bone. Undifferentiated pleomorphic sarcoma (UPS) is an aggressive tumor that usually presents as an asymptomatic subcutaneous mass that exhibits rapid growth with unremarkable skin findings. The diagnosis is usually made with histopathology or immunohistochemistry; once the diagnosis is confirmed, evaluation and workup of the primary tumor, lymph nodes, and metastasis should be made. Treatment is stage-dependent but generally involves en-bloc resection followed by a review of pathology with a discussion of the benefits of adjuvant radiation or chemotherapy. Here, we discuss a case of a 77-year-old patient who presented with a large mass over the right shoulder and echocardiographic findings of cardiac tamponade.


Asunto(s)
Taponamiento Cardíaco , Sarcoma , Adulto , Humanos , Anciano , Taponamiento Cardíaco/diagnóstico , Taponamiento Cardíaco/etiología , Sarcoma/complicaciones , Sarcoma/diagnóstico , Ecocardiografía , Ganglios Linfáticos
6.
RSC Adv ; 12(24): 15167-15179, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35693236

RESUMEN

This study explored the structural, electrical, and magnetic properties of diamagnetic aluminium (Al3+) substituted nickel-zinc-cobalt (Ni-Zn-Co) mixed spinel ferrites, though the research on this area is in the infancy stage. Single-phase cubic spinel structures with the Fd3̄m space group of the synthesized Ni0.4Zn0.35Co0.25Fe(2-x)Al x O4 (0 ≤ x ≤ 0.12) ferrite samples were confirmed by X-ray diffraction (XRD) analysis. The average particle size ranged from 0.67 to 0.39 µm. Selected area electron diffraction (SAED) patterns were indexed according to the space group Fd3m, representing the particle's crystallinity. The optical band gaps ranged from 4.784 eV to 4.766 eV. Frequency-dependent dielectric constants and ac conductivity measurement suggested that the prepared ferrites were highly resistive. Relaxation times were reduced to a low value from 45.45 µs to 1.54 µs with the composition x. The Curie temperatures (T c) were 615-623 K for all samples. Real part permeabilities (µ /) were relatively stable up to an extended frequency range of 106 Hz with relative quality factors (RQF) of around 103. Tuning of the properties indicates that the fabricated ferrites may be promising for high-frequency electronic devices.

7.
RSC Adv ; 12(8): 4656-4671, 2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-35425488

RESUMEN

This study presents a modification of structure-dependent elastic, thermodynamic, magnetic, transport and magneto-dielectric properties of a Ni-Zn-Co ferrite tailored by Gd3+ substitution at the B-site replacing Fe3+ ions. The synthesized composition of Ni0.7Zn0.2Co0.1Fe2-x Gd x O4 (0 ≤ x ≤ 0.12) crystallized with a single-phase cubic spinel structure that belongs to the Fd3̄m space group. The average particle size decreases due to Gd3+ substitution at Fe3+. Raman and IR spectroscopy studies illustrate phase purity, lattice dynamics with cation disorders and thermodynamic conditions inside the studied samples at room temperature (RT = 300 K). Ferromagnetic to paramagnetic phase transition was observed in all samples where Curie temperature (T C) decreases from 731 to 711 K for Gd3+ substitution in Ni-Zn-Co ferrite. In addition, Gd3+ substitution reinforces to decrease the A-B exchange interaction. Temperature-dependent DC electrical resistivity (ρ DC) and temperature coefficient of resistance (TCR) have been surveyed with the variation of the grain size. The frequency-dependent dielectric properties and electric modulus at RT for all samples were observed from 20 Hz to 100 MHz and the conduction relaxation processes were found to spread over an extensive range of frequencies with the increase in the amount of Gd3+ in the Ni-Zn-Co ferrite. The RLC behavior separates the zone of frequencies ranging from resistive to capacitive regions in all the studied samples. Finally, the matching impedance (Z/η 0) for all samples was evaluated over an extensive range of frequencies for the possible miniaturizing application.

8.
Pulm Circ ; 11(4): 20458940211054304, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34707859

RESUMEN

Pulmonary arterial hypertension (PAH) is a cardiopulmonary disease with high mortality. In recent years, it has been recognized that PAH is a multi-organ system disease, involving the systemic circulation, kidneys, skeletal muscles, and the central nervous system, among others. Right heart failure produces congestive hepatopathy, a disease state that has direct consequences on liver biochemistry, histology, and systemic glucose and lipid metabolism. This article aims to summarize the consequences of congestive hepatopathy with an emphasis on liver biochemistry, histology, and PAH-targeted therapy. Furthermore, PAH-specific changes in glucose and lipid metabolism will be discussed.

9.
Biofouling ; 37(4): 372-386, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-34121514

RESUMEN

Although the hull of a recently dry-docked large ship is expected to be relatively smooth, surface scanning and experimentation reveal that it can exhibit an "orange-peel" roughness pattern with an equivalent sand-grain roughness height ks = 0. 101 mm. Using the known ks value and integral boundary layer evolution, a recently cleaned and coated full-scale ship was predicted to experience a significant increase in the average coefficient of friction %ΔC¯f and total hydrodynamic resistance %ΔR¯T during operation. Here the report also discusses two recently reported empirical estimations that can estimate ks directly from measured surface topographical parameters, by-passing the need for experiments on replicated surfaces. The empirical estimations are found to have an accuracy of 4.5 - 5 percentage points in %ΔC¯f.


Asunto(s)
Incrustaciones Biológicas , Navíos , Biopelículas , Fricción , Propiedades de Superficie
10.
Pharmacol Res Perspect ; 9(1): e00710, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33570248

RESUMEN

INTRODUCTION: The ORBITA trial of percutaneous coronary intervention (PCI) versus a placebo procedure for patients with stable angina was conducted across six sites in the United Kingdom via home monitoring and telephone consultations. Patients underwent detailed assessment of medication adherence which allowed us to measure the efficacy of the implementation of the optimization protocol and interpretation of the main trial endpoints. METHODS: Prescribing data were collected throughout the trial. Self-reported adherence was assessed, and urine samples collected at pre-randomization and at follow-up for direct assessment of adherence using high-performance liquid chromatography with tandem mass spectrometry (HPLC MS/MS). RESULTS: Self-reported adherence was >96% for all drugs in both treatment groups at both stages. The percentage of samples in which drug was detected at pre-randomization and at follow-up in the PCI versus placebo groups respectively was: clopidogrel, 96% versus 90% and 98% versus 94%; atorvastatin, 95% versus 92% and 92% versus 91%; perindopril, 95% versus 97% and 85% versus 100%; bisoprolol, 98% versus 99% and 96% versus 97%; amlodipine, 99% versus 99% and 94% versus 96%; nicorandil, 98% versus 96% and 94% versus 92%; ivabradine, 100% versus 100% and 100% versus 100%; and ranolazine, 100% versus 100% and 100% versus 100%. CONCLUSIONS: Adherence levels were high throughout the study when quantified by self-reporting methods and similarly high proportions of drug were detected by urinary assay. The results indicate successful implementation of the optimization protocol delivered by telephone, an approach that could serve as a model for treatment of chronic conditions, particularly as consultations are increasingly conducted online.


Asunto(s)
Angina Estable/cirugía , Cumplimiento de la Medicación/estadística & datos numéricos , Intervención Coronaria Percutánea , Telemedicina , Anciano , Bloqueadores de los Canales de Calcio/uso terapéutico , Fármacos Cardiovasculares/uso terapéutico , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Autoinforme , Método Simple Ciego , Reino Unido
11.
Adv Colloid Interface Sci ; 286: 102295, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33161297

RESUMEN

The physics of foams and emulsions has traditionally been studied using bulk foam/emulsion tests and single film platforms such as the Scheludko cell. Recently there has been a renewed interest in a third class of techniques that we term as single bubble/drop tests, which employ isolated whole bubbles and drops to probe the characteristics of foams and emulsions. Single bubble and drop techniques provide a convenient framework for investigating a number of important characteristics of foams and emulsions, including the rheology, stabilization mechanisms, and rupture dynamics. In this review we provide a comprehensive discussion of the various single bubble/drop platforms and the associated experimental measurement protocols including the construction of coalescence time distributions, visualization of the thin film profiles and characterization of the interfacial rheological properties. Subsequently, we summarize the recent developments in foam and emulsion science with a focus on the results obtained through single bubble/drop techniques. We conclude the review by presenting important venues for future research.

12.
Biochimie ; 176: 110-116, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32623049

RESUMEN

Obesity is a major health problem worldwide. Overweight and obesity directly affect health-related quality of life and also have an important economic impact on healthcare systems. In experimental models, obesity leads to hypothalamic inflammation and loss of metabolic homeostasis. It is known that macroautophagy is decreased in the hypothalamus of obese mice but the role of chaperone-mediated autophagy is still unknown. In this study, we aimed to investigate the role of hypothalamic chaperone-mediated autophagy in response to high-fat diet and also the direct effect of palmitate on hypothalamic neurons. Mice received chow or high-fat diet for 3 days or 1 week. At the end of the experimental protocol, chaperone-mediated autophagy in hypothalamus was investigated, as well as cytokines expression. In other set of experiments, neuronal cell lines were treated with palmitic acid, a saturated fatty acid. We show that chaperone-mediated autophagy is differently regulated in response to high-fat diet intake for 3 days or 1 week. Also, when hypothalamic neurons are directly exposed to palmitate there is activation of chaperone-mediated autophagy. High-fat diet causes hypothalamic inflammation concomitantly to changes in the content of chaperone-mediated autophagy machinery. It remains to be studied the direct role of inflammation and lipids itself on the activation of chaperone-mediated autophagy in the hypothalamus in vivo and also the neuronal implications of chaperone-mediated autophagy inhibition in response to obesity.


Asunto(s)
Autofagia Mediada por Chaperones/efectos de los fármacos , Dieta Alta en Grasa/efectos adversos , Hipotálamo/metabolismo , Neuronas/metabolismo , Obesidad/metabolismo , Ácido Palmítico/farmacología , Animales , Línea Celular , Hipotálamo/patología , Ratones , Neuronas/patología , Obesidad/inducido químicamente , Obesidad/patología , Ácido Palmítico/metabolismo
13.
Skinmed ; 18(1): 54-55, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32167459

RESUMEN

A 79-year-old woman presented to the emergency room with a chief complaint of headache of 1 month's duration. Her medical history consisted of hypertension, congestive heart failure, anemia, chronic kidney disease, and hyperlipidemia. She reported the headache as waxing and waning, and occurring bilaterally in the frontal and occipital regions. On examination, she was found to have mild right-sided ptosis and possible early right-sided papilledema. She was also found to have bilateral shoulder tenderness and scalp tenderness. She denied double vision, vision changes, or jaw claudication.


Asunto(s)
Biopsia/efectos adversos , Traumatismos del Nervio Facial/etiología , Parálisis Facial/etiología , Anciano , Femenino , Cefalea/diagnóstico , Humanos , Arterias Temporales/patología
14.
J Dent Res ; 99(3): 293-301, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31937182

RESUMEN

Stem cell-based therapies could provide a permanent treatment for salivary gland (SG) hypofunction caused by ionizing radiation (IR) injury. However, current challenges for SG stem cells to reach the clinic include surgical invasiveness, amount of tissue needed, cell delivery, and storage methods. The objective of this study was to develop a clinically less invasive method to isolate and expand human SG stem cells and then to obtain a cell-free extract to be used as a therapy for IR-injured SGs. Human labial glands were biopsied, and labial stem cells (LSCs) were expanded by explant culture. The LSC extract (LSCE) was obtained by releasing the cellular components after 3 freeze-thaw cycles and 17,000g force centrifugation. LSCE was injected intravenously into mice that had their SGs injured with 13-Gy IR. Positive (non-IR) and negative (IR) control mice received injections of saline (vehicle control). Three pieces of labial glands (0.1 g weight) could expand 1 to 2 million cells. LSCs had a doubling time of 18.8 h; could differentiate into osteocytes, adipocytes, and chondrocytes; and were positive for mesenchymal stem cell markers. Both angiogenic (FGF-1, FGF-2, KGF, angiopoietin, uPA, VEGF) and antiangiogenic factors (PAI-1, TIMP-1, TSP-1, CD26) were detected in LSCE. In addition, some angiogenic factors (PEDF, PTX3, VEGF) possessed neurotrophic functions. Mice treated with LSCE had 50% to 60% higher salivary flow rate than saline-treated mice at 8 and 12 wk post-IR. Saliva lag time measurements also confirmed that LSCE restored SG function. Histologic analyses of parotids and submandibular glands reported comparable numbers of acinar cells, blood vessels, and parasympathetic nerves and cell proliferation rates in sham IR and LSCE-treated mice, though significantly lower in saline-treated mice. An explant culture method can harvest a large number of LSCs from small pieces of labial glands. LSCE showed clinical potential to mitigate IR-injured SGs.


Asunto(s)
Saliva , Glándulas Salivales , Células Acinares , Animales , Extractos Celulares , Humanos , Ratones
15.
Int J Oral Maxillofac Surg ; 49(7): 940-944, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31926823

RESUMEN

Temporomandibular joint (TMJ) reconstruction is traditionally invasive. Several investigators have developed animal models, including mouse models, to study the TMJ. However, there are no detailed descriptions of a mouse model to be followed for additional research. The goal of this project was to study minimally invasive TMJ regeneration using tissue engineering in mice. As part of the project, a detailed mouse model was developed, which is described in this article. Eight carcasses were used to study the anatomy of the TMJ of the mouse and 36 mice were used to describe the surgical approach and perioperative management. The study showed similarities and differences when compared to humans. One mouse died suddenly 10 days postoperatively, while 35 mice survived the operation. Keratitis and wound dehiscence were the most common complications. Investigators reviewing this paper should be able to use this mouse model to further study TMJ regeneration in mice.


Asunto(s)
Prótesis Articulares , Trastornos de la Articulación Temporomandibular , Animales , Modelos Animales de Enfermedad , Humanos , Ratones , Regeneración , Articulación Temporomandibular
16.
Anticancer Res ; 39(9): 5003-5007, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31519607

RESUMEN

Incorporating bortezomib and/or lenalidomide in the management of plasmablastic lymphoma is an attractive option due to the reported high response rates. However, concerns about overlapping toxicities can deter clinicians from incorporating these novel agents into chemotherapy. In this case report we describe a patient with plasmablastic lymphoma, who received both lenalidomide and bortezomib as part of upfront treatment for a high-risk plasmablastic lymphoma. After completing intensive chemotherapy, the patient was transitioned to a regimen of daily lenalidomide and biweekly bortezomib to decrease the chance of relapse. This maintenance phase was given for 6 months and was well tolerated. Despite having multiple adverse risk factors, the patient remains in remission, 18 months following diagnosis.


Asunto(s)
Antineoplásicos/uso terapéutico , Bortezomib/uso terapéutico , Linfoma Plasmablástico/tratamiento farmacológico , Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor , Bortezomib/administración & dosificación , Manejo de la Enfermedad , Femenino , Humanos , Quimioterapia de Inducción , Imagen por Resonancia Magnética , Quimioterapia de Mantención , Persona de Mediana Edad , Linfoma Plasmablástico/diagnóstico , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X
17.
Vet World ; 11(9): 1222-1228, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30410225

RESUMEN

AIM: The present study was aimed to establish a protocol for the evaluation of the in vitro potency of commercial inactivated Newcastle disease virus (NDV) oil-adjuvanted vaccines using hemagglutination test (HA) and blocking ELISA (B-ELISA) based on polyclonal antibodies. MATERIALS AND METHODS: Aqueous phases from a total of 47 batches of inactivated NDV vaccines manufactured by 20 different companies were extracted with isopropyl myristate. The viral antigen in each sample was detected and quantified by a standard HA test and a B-ELISA assay. To verify the efficiency of the antigen extraction method used in the batches which showed HA and to test the validity of using in vitro antigen quantification by HA and B-ELISA tests, a subset of 13 batches (selected from the total 47 batches) was inoculated in groups of 3-4-week-old specific pathogen-free chickens using the recommended vaccine dose. The immunogenicity of the selected vaccine batches was assessed by the NDV-hemagglutination inhibition antibody titers in individual serum samples collected 4 weeks after vaccination. Further, the efficacy of the vaccines and their protection rates were determined by a challenge test carried out for the vaccinated chickens with the Egyptian 2012 isolate of the virulent NDV genotype VII. RESULTS: A strong correlation was observed between HA titers and B-ELISA mean titers in the tested 47 batches (R2=0.817). This indicated the possibility of using the latter in vitro assays for vaccine potency assessment. The recommended protective NDV antigen titer measured by B-ELISA was determined to be 28 ELISA units per dose. The comparison between the HA titers of the aqueous extracts of test vaccines and the corresponding results of in vivo potency assays (i.e., immunogenicity and efficacy), including antibody titers in the serum of vaccinated birds, indicated that the efficiency of the antigen extraction used may interfere with obtaining a strong correlation between the in vitro and in vivo results. CONCLUSION: HA or B-ELISA tests can be used as rapid and cost-effective alternatives to traditional in vivo potency tests for vaccine potency assessment by quantifying the NDV antigen present in aqueous phase extracts of the tested vaccines. The latter in vitro protocol, however, requires efficient extraction of the antigen to be able to obtain good correlation with the traditional in vivo potency tests.

18.
Med J Malaysia ; 73(5): 291-296, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30350807

RESUMEN

INTRODUCTION: Acinetobacter baumannii (A. baumannii) is commonly found as an agent of nosocomial infections and demonstrates a high antibiotic resistance due to its carbapenemase production. The objectives of this study were to explore the antibiotic resistance pattern, the presence of OXAs genes and the biofilm-producing capacity of A. baumannii isolated from clinical specimens. METHODS: Antibiotics susceptibility testing, detection of OXAs genes and the biofilm-producing capacity were performed using the Kirby Bauer method, polymerase chain reaction (PCR) and adherence quantitative assays, respectively. RESULTS: A total of 80 A. baumannii isolates were mainly obtained from sputum and most of them were resistant to antibiotics. All A. baumannii carried blaOXA-51 gene, yet no blaOXA-24 and blaOXA-58 genes were detected. Fourteen (82.4%) of the 17 meropenem resistant isolates carried blaOXA-23 gene, but it was not found in meropenem sensitive isolates. In addition, sixty (75.0%) of 80 isolates were biofilm producers with 2 (2.5%), 16 (20.0%), and 42 (52.5%) isolates were identified as strong, moderate and weak biofilm producers, respectively. CONCLUSION: Most of A. baumannii isolates had a high level of antibiotic resistance and had a capacity to produce biofilm.


Asunto(s)
Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/genética , Biopelículas/crecimiento & desarrollo , Infección Hospitalaria/microbiología , Genes Bacterianos/genética , beta-Lactamasas/genética , Infecciones por Acinetobacter/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Infección Hospitalaria/genética , Farmacorresistencia Bacteriana/genética , Femenino , Hospitales de Enseñanza , Humanos , Indonesia , Lactante , Recién Nacido , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Centros de Atención Terciaria , Adulto Joven
19.
FASEB J ; 32(3): 1468-1478, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29127186

RESUMEN

The regulation of host factors is a key strategy employed by viruses to suppress host defense systems and enhance their propagation; however, the mechanisms that underlie this regulation is still unclear. Formyl peptide receptor 2 (FPR2) recognizes numerous proinflammatory and anti-inflammatory stimuli, and emerging reports indicate elevated levels of FPR2 in several disease conditions. Although studies have implicated FPR2 in a myriad of inflammatory conditions, how viruses exploit this cell-surface receptor to facilitate disease progression remains unknown. In this study, we show that the activation of TLR3 and TLR7 induces the up-regulation of FPR2. We provide evidence that signal transducer and activator of transcription 3 (STAT3) phosphorylation is critical for the induction of FPR2 by double-stranded RNA, but not single-stranded RNA viral mimetics. Use of bone marrow-derived macrophages (BMDMs) from IFN-αß receptor-deficient mice revealed that signaling via the type I IFN-STAT3 pathway is essential for FPR2 induction. We demonstrate that virus infection with enterovirus 71 and H1N1 PR8 influenza virus results in increased FPR2 expression. Inhibition of STAT3 phosphorylation in virus-infected cells repressed the induction of FPR2, which led to a reduction in viral loads. Finally, the absence of FPR2 in murine BMDMs resulted in lower viral loads, which suggests that FPR2 may be important for virus replication. Altogether, our study provides novel insights into how RNA viruses may hijack the immune system to facilitate their replication and survival. Identification of these regulatory elements may be useful in designing therapeutics for inflammatory disease conditions that are associated with elevated levels of FPR2.-Ampomah, P. B., Moraes, L. A., Lukman, H. M., Lim, L. H. K. Formyl peptide receptor 2 is regulated by RNA mimics and viruses through an IFN-ß-STAT3-dependent pathway.


Asunto(s)
Enterovirus Humano A/inmunología , Infecciones por Enterovirus/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Infecciones por Orthomyxoviridae/inmunología , ARN Viral/inmunología , Receptores de Formil Péptido/inmunología , Factor de Transcripción STAT3/inmunología , Transducción de Señal/inmunología , Animales , Infecciones por Enterovirus/genética , Subtipo H1N1 del Virus de la Influenza A/genética , Interferón beta/genética , Interferón beta/inmunología , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/inmunología , Ratones , Ratones Noqueados , Infecciones por Orthomyxoviridae/genética , ARN Viral/genética , Receptores de Formil Péptido/genética , Factor de Transcripción STAT3/genética , Transducción de Señal/genética , Receptor Toll-Like 3/genética , Receptor Toll-Like 3/inmunología , Receptor Toll-Like 7/genética , Receptor Toll-Like 7/inmunología
20.
Sci Rep ; 7(1): 17925, 2017 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-29263330

RESUMEN

Macrophages are potent immune cells with well-established roles in the response to stress, injury, infection and inflammation. The classically activated macrophages (M1) are induced by lipopolysaccharide (LPS) and express a wide range of pro-inflammatory genes. M2 macrophages are induced by T helper type 2 cytokines such as interleukin-4 (IL4) and express high levels of anti-inflammatory and tissue repair genes. The strong association between macrophages and tumour cells as well as the high incidences of leukocyte infiltration in solid tumours have contributed to the discovery that tumour-associated macrophages (TAMs) are key to tumour progression. Here, we investigated the role of Annexin A1 (ANXA1), a well characterized immunomodulatory protein on macrophage polarization and the interaction between macrophages and breast cancer cells. Our results demonstrate that ANXA1 regulates macrophage polarization and activation. ANXA1 can act dually as an endogenous signalling molecule or as a secreted mediator which acts via its receptor, FPR2, to promote macrophage polarization. Furthermore, ANXA1 deficient mice exhibit reduced tumour growth and enhanced survival in vivo, possibly due to increased M1 macrophages within the tumor microenvironment. These results provide new insights into the molecular mechanisms of macrophage polarization with therapeutic potential to suppress breast cancer growth and metastasis.


Asunto(s)
Anexina A1/metabolismo , Movimiento Celular , Proliferación Celular , Macrófagos/inmunología , Neoplasias Mamarias Animales/patología , Microambiente Tumoral/inmunología , Animales , Anexina A1/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Neoplasias Mamarias Animales/inmunología , Neoplasias Mamarias Animales/metabolismo , Ratones , FN-kappa B/metabolismo , Receptores de Formil Péptido/metabolismo , Transducción de Señal , Células Tumorales Cultivadas
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