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1.
Virol J ; 21(1): 240, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39354538

RESUMEN

BACKGROUND: Infection of mice with mouse-adapted strains of influenza virus has been widely used to establish mouse pneumonia models. Intranasal inoculation is the traditional route for constructing an influenza virus-induced pneumonia mouse model, while intratracheal inoculation has been gradually applied in recent years. In this article, the pathogenicity of influenza virus-induced pneumonia mouse models following intranasal and aerosolized intratracheal inoculation were compared. METHODS: By comparing the two ways of influenza inoculation, intranasal and intratracheal, a variety of indices such as survival rate, body weight change, viral titer and load, pathological change, lung wet/dry ratio, and inflammatory factors were investigated. Meanwhile, the transcriptome was applied for the initial exploration of the mechanism underlying the variations in the results between the two inoculation methods. RESULTS: The findings suggest that aerosolized intratracheal infection leads to more severe lung injury and higher viral loads in the lungs compared to intranasal infection, which may be influenced by the initial site of infection, sialic acid receptor distribution, and host innate immunity. CONCLUSION: Intratracheal inoculation is a better method for modelling severe pneumonia in mice than intranasal infection.


Asunto(s)
Administración Intranasal , Modelos Animales de Enfermedad , Pulmón , Infecciones por Orthomyxoviridae , Carga Viral , Animales , Ratones , Pulmón/virología , Pulmón/patología , Infecciones por Orthomyxoviridae/virología , Infecciones por Orthomyxoviridae/patología , Femenino , Aerosoles , Ratones Endogámicos BALB C , Neumonía Viral/virología , Neumonía Viral/patología , Neumonía Viral/inmunología , Orthomyxoviridae/patogenicidad , Perfilación de la Expresión Génica
2.
J Med Virol ; 95(1): e28150, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36112136

RESUMEN

Coronavirus disease 2019 (COVID-19) remains a serious global threat. The metabolic analysis had been successfully applied in the efforts to uncover the pathological mechanisms and biomarkers of disease severity. Here we performed a quasi-targeted metabolomic analysis on 56 COVID-19 patients from Sierra Leone in western Africa, revealing the metabolomic profiles and the association with disease severity, which was confirmed by the targeted metabolomic analysis of 19 pairs of COVID-19 patients. A meta-analysis was performed on published metabolic data of COVID-19 to verify our findings. Of the 596 identified metabolites, 58 showed significant differences between severe and nonsevere groups. The pathway enrichment of these differential metabolites revealed glutamine and glutamate metabolism as the most significant metabolic pathway (Impact = 0.5; -log10P = 1.959). Further targeted metabolic analysis revealed six metabolites with significant intergroup differences, with glutamine/glutamate ratio significantly associated with severe disease, negatively correlated with 10 clinical parameters and positively correlated with SPO2 (rs = 0.442, p = 0.005). Mini meta-analysis indicated elevated glutamate was related to increased risk of COVID-19 infection (pooled odd ratio [OR] = 2.02; 95% confidence interval [CI]: 1.17-3.50) and severe COVID-19 (pooled OR = 2.28; 95% CI: 1.14-4.56). In contrast, elevated glutamine related to decreased risk of infection and severe COVID-19, the pooled OR were 0.30 (95% CI: 0.20-0.44), and 0.44 (95% CI: 0.19-0.98), respectively. Glutamine and glutamate metabolism are associated with COVID-19 severity in multiple populations, which might confer potential therapeutic target of COVID-19, especially for severe patients.


Asunto(s)
COVID-19 , Ácido Glutámico , Humanos , Ácido Glutámico/metabolismo , Glutamina/metabolismo , Metabolómica , Biomarcadores
3.
J Infect Dis ; 215(7): 1107-1110, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28498995

RESUMEN

We performed Ebola virus disease diagnosis and viral load estimation for Ebola cases in Sierra Leone during the late stage of the 2014-2015 outbreak (January-March 2015) and analyzed antibody and cytokine levels and the viral genome sequences. Ebola virus disease was confirmed in 86 of 1001 (9.7%) patients, with an overall case fatality rate of 46.8%. Fatal cases exhibited significantly higher levels of viral loads, cytokines, and chemokines at late stages of infection versus early stage compared with survivors. The viruses converged in a new clade within sublineage 3.2.4, which had a significantly lower case fatality rate.


Asunto(s)
Ebolavirus/genética , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/inmunología , Carga Viral , Anticuerpos Antivirales/sangre , Citocinas/sangre , Brotes de Enfermedades , Genoma Viral , Humanos , Sierra Leona/epidemiología , Sobrevivientes
4.
J Labelled Comp Radiopharm ; 60(9): 385-393, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28423195

RESUMEN

The purpose of our study was to develop and evaluate a novel integrin αv ß3 -specific delivery carrier for transfection of siRNA in malignant tumors. We adopted arginine-glycine-aspartate (RGD) motif as a tissue target for specific recognition of integrin αν ß3 . A chimaeric peptide was synthesized by adding nonamer arginine residues (9-arginine [9R]) at the carboxy terminus of cyclic-RGD dimer, designated as c(RGD)2 -9R, to enable small interfering RNA (siRNA) binding. To test the applicability of the delivery carrier in vivo, c(RGD)2 -9R was labeled with radionuclide of technetium-99m. Biodistribution and γ-camera imaging studies were performed in HepG2 xenograft-bearing nude mice. As results, an optimal 10:1 molar ratio of 99m Tc-c(RGD)2 -9R to siRNA was indicated by the electrophoresis on agarose gels. 99m Tc-c(RGD)2 -9R/siRNA remained stable under a set of conditions in vitro. For in vivo study, tumor radioactivity uptake of 99m Tc-c(RGD)2 -9R/siRNA in nude mice bearing HepG2 xenografts was significantly higher than that of control probe (P < .05). The xenografts were clearly visualized at 4 hours till 6 hours noninvasively after intravenous injection of 99m Tc-c(RGD)2 -9R/siRNA, while the xenografts were not visualized at any time after injection of control probe. It was concluded that c(RGD)2 -9R could be an effective siRNA delivery carrier. Technetium-99m radiolabeled-delivery carrier represents a potential imaging strategy for RNAi-based therapy.


Asunto(s)
Portadores de Fármacos/química , Neoplasias Hepáticas/patología , Péptidos Cíclicos/química , ARN Interferente Pequeño/química , ARN Interferente Pequeño/genética , Transfección , Animales , Dimerización , Portadores de Fármacos/metabolismo , Portadores de Fármacos/farmacocinética , Femenino , Células Hep G2 , Humanos , Integrina alfaVbeta3/metabolismo , Marcaje Isotópico , Neoplasias Hepáticas/diagnóstico por imagen , Ratones , Ratones Desnudos , Cintigrafía , Tecnecio/química , Distribución Tisular
5.
Sensors (Basel) ; 16(9)2016 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-27598160

RESUMEN

Locomotion mode identification is essential for the control of a robotic rehabilitation exoskeletons. This paper proposes an online support vector machine (SVM) optimized by particle swarm optimization (PSO) to identify different locomotion modes to realize a smooth and automatic locomotion transition. A PSO algorithm is used to obtain the optimal parameters of SVM for a better overall performance. Signals measured by the foot pressure sensors integrated in the insoles of wearable shoes and the MEMS-based attitude and heading reference systems (AHRS) attached on the shoes and shanks of leg segments are fused together as the input information of SVM. Based on the chosen window whose size is 200 ms (with sampling frequency of 40 Hz), a three-layer wavelet packet analysis (WPA) is used for feature extraction, after which, the kernel principal component analysis (kPCA) is utilized to reduce the dimension of the feature set to reduce computation cost of the SVM. Since the signals are from two types of different sensors, the normalization is conducted to scale the input into the interval of [0, 1]. Five-fold cross validation is adapted to train the classifier, which prevents the classifier over-fitting. Based on the SVM model obtained offline in MATLAB, an online SVM algorithm is constructed for locomotion mode identification. Experiments are performed for different locomotion modes and experimental results show the effectiveness of the proposed algorithm with an accuracy of 96.00% ± 2.45%. To improve its accuracy, majority vote algorithm (MVA) is used for post-processing, with which the identification accuracy is better than 98.35% ± 1.65%. The proposed algorithm can be extended and employed in the field of robotic rehabilitation and assistance.


Asunto(s)
Algoritmos , Dispositivo Exoesqueleto , Locomoción , Rehabilitación , Robótica , Máquina de Vectores de Soporte , Adulto , Humanos , Masculino , Procesamiento de Señales Asistido por Computador
6.
Echocardiography ; 30(3): 345-53, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23336391

RESUMEN

OBJECTIVES: This study assessed the ability of live/real time three-dimensional transesophageal echocardiography (3DTEE) in measuring (1) atrial septal defect (ASD) maximum dimension, area, and adjacent rim size, (2) ASD occluder left and right atrial disk size, (3) length of contact between the left atrial (LA) disk and the aorta, and in (4) assessing device related complications such as residual shunt, device embolization, and device encroachment upon adjacent cardiac structures. MATERIALS AND METHODS: 3DTEE images acquired during percutaneous ASD closure by the Amplatzer Septal Occluder in 15 adult patients were retrospectively analyzed. Offline analysis was done using both the Philips 5500 ultrasound system and Philips QLAB software. 3D color flow Doppler images were used to assess residual ASD shunting. RESULTS: The Philips 5500 and Philips QLAB measurements correlated well for ASD maximum dimension and area measurements. The Philips QLAB 3DTEE disk size measurements also correlated well with the manufacturer obtained sizes. The aortic rim was deficient in 7 of the 15 patients, and the mean ASD occluder device size was 4 mm greater than the mean ASD maximum dimension. The LA occluder disk was in contact with the aorta throughout the cardiac cycle in 12 of the 15 patients, and the LA occluder disk size correlated significantly with the contact length with the aorta. CONCLUSION: Most of the patients demonstrated contact between the LA occluder disk and the aorta throughout the cardiac cycle. 3DTEE may be useful in identifying patients at greater risk for aortic erosion.


Asunto(s)
Ecocardiografía Tridimensional/métodos , Ecocardiografía Transesofágica/métodos , Defectos del Tabique Interatrial/diagnóstico por imagen , Defectos del Tabique Interatrial/cirugía , Dispositivo Oclusor Septal , Cirugía Asistida por Computador/métodos , Adolescente , Adulto , Anciano , Sistemas de Computación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del Tratamiento , Adulto Joven
8.
Nucl Med Commun ; 43(2): 186-192, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34783717

RESUMEN

OBJECTIVE: T cell lymphomas are associated with an aggressive worse prognosis. This study is designed to assess T cell lymphomas using 18F-FDG PET/CT. METHODS: Sixty-four patients with newly diagnosed T cell lymphomas underwent PET/computed tomography (PET/CT) scans, 47 cases who were fully followed up were retrospectively reviewed and analyzed. Overall survival (OS) and progression-free survival (PFS) were recorded for prognosis. We measured the maximum standardized uptake value (SUVmax) in all cases, analyzed the correlation between SUVmax and survival and other clinicopathologic parameters. Kaplan-Meier log-rank tests were then used to compare the survival of high and low PET/CT parameter groups, and multivariate Cox proportional hazards regression analysis was carried out to identify predictors of OS and PFS. RESULTS: With a median follow-up of 26.5 (range 0.7-117.5) months, the 1-, 2- and 3-year OS were 75.6, 61.7 and 49.2%, and PFS were 49.3, 39.9 and 29.9%, respectively in 47 patients. Among them, 33 cases progressed with a median time of 9.5 (0.7-115.0) months, and 26 patients died with a median survival time of 26.5 (0.7-117.5) months. Multivariate analysis showed the following independent prognostic factors for OS: age >60 years (P = 0.002), SUVmax >9.7 (P = 0.009) and extranodal involvement of more than one site (P = 0.018). In addition, lactate dehydrogenase level (P = 0.003) and B symptoms (P = 0.018) were independent risk factors for PFS. CONCLUSION: Pretherapy SUVmax may serve as an independent predictor of outcome in patients with newly diagnosed T cell lymphomas.


Asunto(s)
Tomografía Computarizada por Tomografía de Emisión de Positrones
9.
Int J Nanomedicine ; 17: 3325-3341, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35937077

RESUMEN

Purpose: Current vaccines for the SARS-CoV-2 virus mainly induce neutralizing antibodies but overlook the T cell responses. This study aims to generate an exosomal vaccine carrying T cell epitope peptides of SARS-CoV-2 for the induction of CD8+ T cell response. Methods: Thirty-one peptides presented by HLA-A0201 molecule were conjugated to the DMPE-PEG-NHS molecules, and mixed with DSPE-PEG to form the peptide-PEG-lipid micelles, then fused with exosomes to generate the exosomal vaccine, followed by purification using size-exclusion chromatography and validation by Western blotting, liquid nuclear magnetic resonance (NMR) test and transmission electron microscopy. Furthermore, the exosomal vaccine was mixed with Poly (I:C) adjuvant and subcutaneously administered for three times into the hybrid mice of HLA-A0201/DR1 transgenic mice with wild-type mice. Then, the epitope-specific T cell responses were detected by ex vivo ELISPOT assay and intracellular cytokine staining. Results: The exosomal vaccine was purified from the Peak 2 fraction of FPLC and injected into the hybrid mice for three times. The IFN-γ spot forming units and the frequencies of IFN-γ+/CD8+ T cells were 10-82-fold and 13-65-fold, respectively, higher in the exosomal vaccine group compared to the Poly (I:C) control group, without visible organ toxicity. In comparison with the peptides cocktail vaccine generated in our recent work, the exosomal vaccine induced significantly stronger T cell response. Conclusion: Exosomal vaccine loading T cell epitope peptides of SARS-CoV-2 virus was initially generated without pre-modification for both peptides and exosomes, and elicited robust CD8+ T cell response in HLA-A transgenic mice.


Asunto(s)
COVID-19 , Vacunas , Animales , Linfocitos T CD8-positivos , COVID-19/prevención & control , Vacunas contra la COVID-19 , Epítopos de Linfocito T , Humanos , Ratones , Ratones Transgénicos , Péptidos , Poli I-C , SARS-CoV-2
10.
Proc Natl Acad Sci U S A ; 105(23): 8091-6, 2008 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-18523003

RESUMEN

The mortality of human infection by influenza A/H5N1 virus can exceed 80%. The high mortality and its poor response to the neuraminidase inhibitor oseltamivir have been attributed to uncontrolled virus-induced cytokine storm. We challenged BALB/c mice with 1,000 LD50 of influenza A/Vietnam/1194/04. Survival, body weight, histopathology, inflammatory markers, viral loads, T lymphocyte counts, and neutralizing antibody response were documented in infected mice treated individually or in combination with zanamvir, celecoxib, gemfibrozil, and mesalazine. To imitate the real-life scenario, treatment was initiated at 48 h after viral challenge. There were significant improvements in survival rate (P = 0.02), survival time (P < 0.02), and inflammatory markers (P < 0.01) in the group treated with a triple combination of zanamivir, celecoxib, and mesalazine when compared with zanamivir alone. Zanamivir with or without immunomodulators reduced viral load to a similar extent. Insignificant prolongation of survival was observed when individual agents were used alone. Significantly higher levels of CD4+ and CD8+ T lymphocytes and less pulmonary inflammation were also found in the group receiving triple therapy. Zanamivir alone reduced viral load but not inflammation and mortality. The survival benefits of adding celecoxib and mesalazine to zanamivir could be caused by their synergistic effects in reducing cytokine dysfunction and preventing apoptosis. Combinations of a neuraminidase inhibitor with these immunomodulators should be considered in randomized controlled treatment trials of patients suffering from H5N1 infection.


Asunto(s)
Antivirales/uso terapéutico , Factores Inmunológicos/uso terapéutico , Subtipo H5N1 del Virus de la Influenza A/fisiología , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Albúminas/metabolismo , Animales , Antivirales/farmacología , Peso Corporal/efectos de los fármacos , Quimiocinas/metabolismo , Femenino , Factores Inmunológicos/farmacología , Subtipo H5N1 del Virus de la Influenza A/efectos de los fármacos , Pulmón/efectos de los fármacos , Pulmón/patología , Pulmón/virología , Recuento de Linfocitos , Ratones , Ratones Endogámicos BALB C , Prostaglandinas/metabolismo , Análisis de Supervivencia , Tasa de Supervivencia , Linfocitos T/efectos de los fármacos , Linfocitos T/virología , Factores de Tiempo , Carga Viral
11.
Virol Sin ; 36(6): 1484-1491, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34403037

RESUMEN

The sudden emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) has caused global panic in 2003, and the risk of SARS-CoV outbreak still exists. However, no specific antiviral drug or vaccine is available; thus, the development of therapeutic antibodies against SARS-CoV is needed. In this study, a nanobody phage-displayed library was constructed from peripheral blood mononuclear cells of alpacas immunized with the recombinant receptor-binding domain (RBD) of SARS-CoV. Four positive clones were selected after four rounds of bio-panning and subjected to recombinant expression in E. coli. Further biological identification demonstrated that one of the nanobodies, S14, showed high affinity to SARS-CoV RBD and potent neutralization activity at the picomole level against SARS-CoV pseudovirus. A competitive inhibition assay showed that S14 blocked the binding of SARS-CoV RBD to either soluble or cell-expressed angiotensin-converting enzyme 2 (ACE2). In summary, we developed a novel nanobody targeting SARS-CoV RBD, which might be useful for the development of therapeutics against SARS.


Asunto(s)
COVID-19 , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Anticuerpos Neutralizantes , Anticuerpos Antivirales/metabolismo , Escherichia coli/metabolismo , Humanos , Leucocitos Mononucleares/metabolismo , Unión Proteica , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/metabolismo , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/metabolismo
12.
Cancer Res ; 67(18): 8536-43, 2007 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17875693

RESUMEN

Proteasome inhibitors are novel antitumor agents against multiple myeloma and other malignancies. Despite the increasing clinical application, the molecular basis of their antitumor effect has been poorly understood due to the involvement of the ubiquitin-proteasome pathway in multiple cellular metabolisms. Here, we show that treatment of cells with proteasome inhibitors has no significant effect on nonhomologous end joining but suppresses homologous recombination (HR), which plays a key role in DNA double-strand break (DSB) repair. In this study, we treat human cells with proteasome inhibitors and show that the inhibition of the proteasome reduces the efficiency of HR-dependent repair of an artificial HR substrate. We further show that inhibition of the proteasome interferes with the activation of Rad51, a key factor for HR, although it does not affect the activation of ATM, gammaH2AX, or Mre11. These data show that the proteasome-mediated destruction is required for the promotion of HR at an early step. We suggest that the defect in HR-mediated DNA repair caused by proteasome inhibitors contributes to antitumor effect, as HR plays an essential role in cellular proliferation. Moreover, because HR plays key roles in the repair of DSBs caused by chemotherapeutic agents such as cisplatin and by radiotherapy, proteasome inhibitors may enhance the efficacy of these treatments through the suppression of HR-mediated DNA repair pathways.


Asunto(s)
Antineoplásicos/farmacología , Inhibidores de Cisteína Proteinasa/farmacología , Roturas del ADN de Doble Cadena , Reparación del ADN/efectos de los fármacos , Leupeptinas/farmacología , Inhibidores de Proteasoma , Recombinación Genética/efectos de los fármacos , Animales , Proteínas de la Ataxia Telangiectasia Mutada , Proteína BRCA1/metabolismo , Proteína BRCA2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Unión al ADN/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/enzimología , Fibroblastos/fisiología , Genes BRCA1 , Células HeLa , Humanos , Ratones , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Recombinasa Rad51/metabolismo , Proteínas Supresoras de Tumor/metabolismo
13.
Int J Clin Pharm ; 41(6): 1652-1657, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31696422

RESUMEN

Background The participation of clinical pharmacists in the treatment of acute pancreatitis has rarely been reported. Objective The aim of this study was to retrospectively evaluate the impact of intervention of clinical pharmacists on the treatment of acute pancreatitis. Setting An academic teaching hospital in Taizhou, Jiangsu, China. Method Two hundred and twenty-eight patients with acute pancreatitis were retrospectively enrolled from July 2017 to July 2018 and divided into an intervention group (n = 119) and a control group (n = 109) according to whether a clinical pharmacist was involved. No significant differences in the baseline clinical characteristics were found between the groups. Clinical pharmacists participated in drug formulation and adjustment, pharmaceutical care, and follow-up. Main outcome measure Clinical outcomes, average hospital stays, costs, incidence of adverse drug reactions, 1-month subsequent visit rate, and patient satisfaction between the two groups were measured. Results The clinical symptoms of patients in both groups were relieved after treatment. There were no significant differences between the groups in computed tomography grades after treatment, incidence of adverse drug reactions, or average hospital stays. However, the intervention group had lower total costs of hospitalization, drugs and antibiotics but higher rates of 1-month subsequent visits and satisfaction compared with the control group. Conclusion The intervention of clinical pharmacists in the treatment of acute pancreatitis can effectively reduce costs of hospitalization, drug and antibiotics and improve follow-up compliance and patient satisfaction.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Pancreatitis/tratamiento farmacológico , Farmacéuticos/organización & administración , Servicio de Farmacia en Hospital/organización & administración , Enfermedad Aguda , Adulto , Anciano , Antibacterianos/administración & dosificación , China , Femenino , Hospitalización/estadística & datos numéricos , Hospitales de Enseñanza , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Rol Profesional , Estudios Retrospectivos
14.
DNA Repair (Amst) ; 6(3): 280-92, 2007 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-17123873

RESUMEN

One of the earliest events in the signal transduction cascade that initiates a DNA damage checkpoint is the phosphorylation on serine 139 of histone H2AX (gammaH2AX) at DNA double-strand breaks (DSBs). However, the role of gammaH2AX in DNA repair is poorly understood. To address this question, we generated chicken DT40 cells carrying a serine to alanine mutation at position 139 of H2AX (H2AX(-/S139A)) and examined their DNA repair capacity. H2AX(-/S139A) cells exhibited defective homologous recombinational repair (HR) as manifested by delayed Rad51 focus formation following ionizing radiation (IR) and hypersensitivity to the topoisomerase I inhibitor, camptothecin (CPT), which causes DSBs at replication blockage. Deletion of the Rad51 paralog gene, XRCC3, also delays Rad51 focus formation. To test the interaction of Xrcc3 and gammaH2AX, we disrupted XRCC3 in H2AX(-/S139A) cells. XRCC3(-/-)/H2AX(-/S139A) mutants were not viable, although this synthetic lethality was reversed by inserting a transgene that conditionally expresses wild-type H2AX. Upon repression of the wild-type H2AX transgene, XRCC3(-/-)/H2AX(-/S139A) cells failed to form Rad51 foci and exhibited markedly increased levels of chromosomal aberrations after CPT treatment. These results indicate that H2AX and XRCC3 act in separate arms of a branched pathway to facilitate Rad51 assembly.


Asunto(s)
Proteínas Aviares/fisiología , Reparación del ADN/fisiología , Proteínas de Unión al ADN/fisiología , Histonas/fisiología , Recombinasa Rad51/metabolismo , Recombinación Genética , Animales , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Camptotecina/farmacología , Células Cultivadas , Pollos , Daño del ADN/fisiología , Proteínas de Unión al ADN/genética , Inhibidores Enzimáticos/farmacología , Rayos gamma , Inestabilidad Genómica , Histonas/genética , Modelos Genéticos , Recombinasa Rad51/genética , Transfección
15.
Neurosci Res ; 61(4): 420-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18554735

RESUMEN

GATA binding protein 3 (GATA3) is an important regulator of central nervous system (CNS) development, but its expression pattern in the postnatal CNS has not been studied. In the present study, we examined the distribution of GATA3 mRNA in the mouse CNS at different postnatal stages by in situ hybridization. During the first 2 weeks of postnatal development, numerous GATA3-expressing cells were found in the intergeniculate leaf, ventral lateral geniculate nucleus, pretectal nucleus, nucleus of the posterior commissure, superior colliculus, inferior colliculus, periaqueductal grey, substantia nigra and raphe nuclei. Few notable changes in the profile of GATA3 expression occurred over this time period. As postnatal development progressed, however, GATA3 expression weakened, and was maintained in only a few regions of the adult CNS. Throughout the brain, we found that GATA3-expressing cells were NeuN-positive, and no colocalization with glial fibrillary acidic protein (GFAP) was observed. In the substantia nigra, GATA3 was exclusively expressed in cells of the reticulate part and some of which were found to be GABAergic. This study presents a comprehensive overview of GATA3 expression in the CNS throughout postnatal life, and the dynamics that we observed provide insights for further investigations of the roles of GATA3 in postnatal development and the maintenance of the mature CNS.


Asunto(s)
Sistema Nervioso Central/crecimiento & desarrollo , Sistema Nervioso Central/metabolismo , Factor de Transcripción GATA3/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , Factores de Edad , Animales , Animales Recién Nacidos , Sistema Nervioso Central/citología , Factor de Transcripción GATA3/genética , Glutamato Descarboxilasa/genética , Glutamato Descarboxilasa/metabolismo , Ratones , Ratones Endogámicos C57BL , Neuronas/metabolismo , ARN Mensajero/metabolismo , Tirosina 3-Monooxigenasa/metabolismo
16.
J Phys Chem B ; 109(9): 3759-63, 2005 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-16851422

RESUMEN

Co49Pt51 nanowire arrays with an average diameter of 35 nm and lengths up to several micrometers were grown in an ordered porous anodic aluminum oxide (AAO) template using direct-current electrodeposition. The as-deposited samples were annealed at 100, 200, 300, 400, 500, 600, and 700 degrees C, respectively. The temperature dependence of the magnetic property of the Co49Pt51 nanowire arrays associated with the microstructure was analyzed by X-ray diffraction and a vibrating sample magnetometer. Magnetic measurements show that the samples both as-prepared and annealed at low temperatures have excellent perpendicular anisotropy. The perpendicular coercivity (Hc(perpendicular)) of Co49Pt51 alloy nanowire arrays increases dramatically as the annealing temperature (T(A)) rises, reaches a maximum(Hc(perpendicular) = 2770 Oe) at 400 degrees C, and then decreases sharply as T(A) rises further. This phenomenon should be attributed to the special structure of the nanowire arrays/AAO, and the microstructure factors significantly change during the annealing process.

17.
Beijing Da Xue Xue Bao Yi Xue Ban ; 37(3): 287-91, 2005 Jun 18.
Artículo en Zh | MEDLINE | ID: mdl-15968322

RESUMEN

OBJECTIVE: To investigate the clinical value of dual-phase imaging of 18F-fluoro-2-deoxy-D-glucose (18F-FDG) using single photon emission computed tomography with coincidence detection (SPECT with coincidence) for differentiating benign and malignant lesions. METHODS: Thirty patients with unknown lesions from June 2003 to March 2004 in our hospital were enrolled in this study. All patients underwent dual-phase imaging of 18F-FDG SPECT with coincidence. The early images were obtained 60 min post injection. And the patients were divided into 2 groups, one receiving delayed scans at 210 min after 18F-FDG injection and the other at 270 min. Lesion status was determined by pathologic findings or by clinical follow-up. RESULTS: Forty-eight lesions (30 malignant and 18 benign lesions verified by pathologic findings or clinical follow-up) of 30 patients were detected by dual-phase imaging, in which there were 29 true positive results, 15 true negative, 3 false positive and 1 false negative. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of dual-phase imaging were 96.7%, 83.3%, 91.6%, 90.6%, and 93.8%, respectively. Those of early imaging and CT were 93.3%, 72.2%, 85.4%, 84.8%, 86.7% and 76.9%, 57.1%, 70.0%, 76.9%, 57.1%, respectively. The T/NT of all malignant lesions (except 1 false negative case) in delayed imaging were significantly increased (t=-3.071, P<0.01). However, there were no statistical differences in the T/NT of benign lesions (t=0.398, P=0.695) between early and delayed imagings. CONCLUSION: Dual-phase imaging of FDG SPECT with coincidence provides benefit for differentiating benign and malignant lesions.


Asunto(s)
Radioisótopos de Flúor , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
mBio ; 6(2)2015 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-25805734

RESUMEN

UNLABELLED: Hepatic injuries in hepatitis B virus (HBV) patients are caused by immune responses of the host. In our previous study, microRNA-146a (miR-146a), an innate immunity-related miRNA, and complement factor H (CFH), an important negative regulator of the alternative pathway of complement activation, were differentially expressed in HBV-expressing and HBV-free hepatocytes. Here, the roles of these factors in HBV-related liver inflammation were analyzed in detail. The expression levels of miR-146a and CFH in HBV-expressing hepatocytes were assessed via analyses of hepatocyte cell lines, transgenic mice, adenovirus-infected mice, and HBV-positive human liver samples. The expression level of miR-146a was upregulated in HBV-expressing Huh-7 hepatocytes, HBV-expressing mice, and patients with HBV infection. Further results demonstrated that the HBV X protein (HBx) was responsible for its effects on miR-146a expression through NF-κB-mediated enhancement of miR-146a promoter activity. HBV/HBx also downregulated the expression of CFH mRNA in hepatocyte cell lines and the livers of humans and transgenic mice. Furthermore, overexpression and inhibition of miR-146a in Huh-7 cells downregulated and upregulated CFH mRNA levels, respectively. Luciferase reporter assays demonstrated that miR-146a downregulated CFH mRNA expression in hepatocytes via 3'-untranslated-region (UTR) pairing. The overall effect of this process in vivo is to promote liver inflammation. These results demonstrate that the HBx-miR-146a-CFH-complement activation regulation pathway might play an important role in the immunopathogenesis of chronic HBV infection. These findings have important implications for understanding the immunopathogenesis of chronic hepatitis B and developing effective therapeutic interventions. IMPORTANCE: Hepatitis B virus (HBV) remains an important pathogen and can cause severe liver diseases, including hepatitis, liver cirrhosis, and hepatocellular carcinoma. Although HBV was found in 1966, the molecular mechanisms of pathogenesis are still poorly understood. In the present study, we found that the HBV X protein (HBx) promoted the expression of miR-146a, an innate immunity-related miRNA, through the NF-κB signal pathway and that increasingly expressed miR-146a downregulated its target complement factor H (CFH), an important negative regulator of the complement alternative pathway, leading to the promotion of liver inflammation. We demonstrated that the HBx-miR-146a-CFH-complement activation regulation pathway is potentially an important mechanism of immunopathogenesis caused by chronic HBV infection. Our data provide a novel molecular mechanism of HBV pathogenesis and thus help to understand the correlations between the complement system, an important part of innate immunity, and HBV-associated disease. These findings will also be important to identify potential therapeutic targets for HBV infection.


Asunto(s)
Factor H de Complemento/antagonistas & inhibidores , Hepatitis B/inmunología , Hepatitis B/patología , Interacciones Huésped-Patógeno , MicroARNs/biosíntesis , Transactivadores/metabolismo , Regulación hacia Arriba , Animales , Línea Celular , Hepatocitos/virología , Humanos , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Reguladoras y Accesorias Virales
19.
Beijing Da Xue Xue Bao Yi Xue Ban ; 36(6): 612-5, 2004 Dec.
Artículo en Zh | MEDLINE | ID: mdl-15605093

RESUMEN

OBJECTIVE: To compare the estimation of glomerular filtration rate (GFR) by renal dynamic imaging with that estimated by two-sample method and evaluate the reliability of measurement of GFR by renal dynamic imaging. METHODS: The study was performed in 54 patients (33 males and 21 females; aged 15 to 82 years) with primary or secondary chronic nephrosis. The patients were intravenously bolus injected with 185 MBq /1mL of (99)Tc(m)-DTPA 20 min after drinking 300 mL of water. Renal dynamic imaging was performed and the image was processed according to standard procedure (Gates' method) to obtain GFR. 3 mL of blood was withdrawn 2 h and 4 h postinjection, respectively, and radioactivity of 1mL plasma was measured. GFR was calculated by the formula of two-sample method. The correlation of GFRs measured by renal dynamic imaging and by two-sample method was analyzed using regression analysis. The correlations of GFRs determined by the two methods with urea and creatinine were also measured. RESULTS: The GFR measured by renal dynamic imaging was slightly lower than that measured by two-sample method. Excellent correlation was obtained by two methods with r= 0.881 5 and P<0.01. The linear regression equation was GFR (renal dynamic imaging method)=0.661 4GFR (two-sample method) +21.89. The related lines of GFRs measured by the two methods with urea or creatinine were similar, which indicated the two methods were similar in identifying the changes in renal function. GFRs measured by the two methods showed good agreement for most of patients except three patients who were too thin or too fat. CONCLUSION: Generally, GFR obtained by renal dynamic imaging is reliable for identifying the changes in renal function and correlated well with GFR obtained by two-sample method. But great error may be obtained with specific individuals, such as too thin or too fat subjects.


Asunto(s)
Tasa de Filtración Glomerular , Nefrosis/fisiopatología , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Creatinina/sangre , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Nefrosis/diagnóstico , Radiofármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Pentetato de Tecnecio Tc 99m
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