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1.
Environ Sci Technol ; 58(19): 8554-8564, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38634679

RESUMEN

Peracetic acid (PAA) oxidation catalyzed by metal-free carbons is promising for advanced water decontamination. Nevertheless, developing reaction-oriented and high-performance carbocatalysts has been limited by the ambiguous understanding of the intrinsic relationship between carbon chemical/molecular structure and PAA transformation behavior. Herein, we comprehensively investigated the PAA activation using a family of well-defined sp2/sp3 carbon hybrids from annealed nanodiamonds (ANDs). The activity of ANDs displays a volcano-type trend, with respect to the sp2/sp3 ratio. Intriguingly, sp3-C-enriched AND exhibits the best catalytic activity for PAA activation and phenolic oxidation, which is different from persulfate chemistry in which the sp2 network normally outperforms sp3 hybridization. At the electron-rich sp2-C site, PAA undergoes a reduction reaction to generate a reactive complex (AND-PAA*) and induces an electron-transfer oxidation pathway. At the sp3-C site adjacent to C═O, PAA is oxidized to surface-confined OH* and O* successively, which ultimately evolves into singlet oxygen (1O2) as the primary reactive species. Benefiting from the dual nonradical regimes on sp2/sp3 hybrids, AND mediates a sustainable redox recycle with PAA to continuously generate reactive species to attack water contaminants, meanwhile maintaining structural/chemical integrity and exceptional reusability in cyclic runs.


Asunto(s)
Ácido Peracético , Ácido Peracético/química , Catálisis , Nanodiamantes/química , Purificación del Agua/métodos , Oxidación-Reducción , Contaminantes Químicos del Agua/química , Agua/química
2.
J Electrocardiol ; 87: 153805, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39326158

RESUMEN

INTRODUCTION: Observational studies have suggested associations between Brugada syndrome (BrS) and electrocardiograms traits. Nonetheless, the causal relationships remains uncertain in observational studies. This study aims to investigate the causal relationships between BrS phenotypic risk and electrocardiogram traits using Mendelian randomization (MR) analysis and colocalization analysis. METHODS: MR analysis was performed to investigate the causal relationships between BrS phenotype risk and electrocardiogram traits (P wave duration, PR interval, QRS wave duration, ST segment duration, T wave duration, QT interval, heart rate (HR) and heart rate variability). The genetic instruments for BrS (number of cases = 12,821) were obtained from the latest GWAS. GWAS summary data of electrocardiogram traits were obtained from the MRC-IEU and GWAS catalog databases. The causal relationships were obtained through MR methods, and sensitivity analyses (e.g. Cochran's Q test, MR-PRESSO). Furthermore, the causal relationships were evaluated whether they were driven by one linkage disequilibrium using colocalization analysis. RESULTS: We found that there are positive causal relationships between BrS phenotypic risk and P wave duration, PR interval, QRS wave duration and QT interval, respectively (IVWP: ß = 1.238, 95 % CI = 0.857-1.619, P<0.001; IVWPR: ß = 2.199, 95 % CI = 1.358-3.039, P<0.001; IVWQRS: ß = 0.157, 95 % CI = 0.115-0.198, P<0.001; IVWQT: ß = 0.593, 95 % CI = 0.391-0.796, P<0.001), and there is a negative causal relationship between BrS phenotypic risk and heart rate (IVWHR: ß = -0.023, 95 % CI = -0.03 âˆ¼ -0.015, P<0.001). Additionally, there are bidirectional causal relationships between BrS phenotypic risk and P wave duration and PR interval, respectively (IVWP: OR = 1.217, 95 % CI = 1.118-1.325, P<0.001; IVWPR: OR = 1.02, 95 % CI = 1.008-1.032, P = 0.001). Furthermore, colocalization analysis identified that the causal relationships between BrS phenotype risk and P wave duration, PR interval and QRS wave duration were driven by rs6790396, rs6801957 and rs6801957, respectively. CONCLUSIONS: Bidirectional causal relationships were identified between BrS phenotypic risk and P wave duration and PR interval, respectively. There were positive causal relationships between BrS phenotypic risk and QRS wave duration and QT interval, respectively, and there is a negative causal relationship between BrS phenotypic risk and heart rate.

3.
J Tissue Viability ; 33(2): 208-214, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38599978

RESUMEN

OBJECTIVE: In this study, we evaluated the pH (potential of hydrogen) value of diabetic foot ulcers and explored the relationship between the pH value and infection, sinus formation, stasis dermatitis, and the process of healing. METHODS: From October 2022 to June 2023, 99 patients with 106 diabetic foot ulcers were selected. Diabetic foot ulcers were treated in a standardized manner by a professional team. The pH value, area, PUSH (Pressure Ulcer Scale for Healing) score, and the degree of infection of the wounds were compared before and after the treatment. RESULTS: The baseline wound pH value in 76.4% of the patients was in the alkaline range and was closely related to the degree of infection (P < 0.05). As the ulcers healed, the pH decreased. For moderately and severely infected diabetic foot ulcers, each unit decrease in pH was associated with a decrease in the PUSH score of approximately 4.6 points (P < 0.05). The pH values of wounds with surrounding ecchymosis dermatitis were significantly higher than those of wounds without ecchymosis dermatitis (P < 0.05). The pH value of the wound with a sinus tract was higher. After treatment, there was no significant difference in pH value between the patients with and without sinus tracts (P < 0.05). CONCLUSIONS: The measurement of pH value is efficient and simple, and the patient suffers no discomfort in the process. The change in pH helps predict the healing process of diabetic foot ulcers and quickly identify whether there are key factors such as infection and ischemia in the wound. It is suggested that dynamic pH monitoring be included in the whole course evaluation and intervention strategy development of diabetic foot.


Asunto(s)
Pie Diabético , Cicatrización de Heridas , Humanos , Pie Diabético/fisiopatología , Cicatrización de Heridas/fisiología , Masculino , Femenino , Persona de Mediana Edad , Concentración de Iones de Hidrógeno , Anciano , Anciano de 80 o más Años , Adulto
4.
Angew Chem Int Ed Engl ; 62(10): e202218510, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36625681

RESUMEN

Generating FeIV =O on single-atom catalysts by Fenton-like reaction has been established for water treatment; however, the FeIV =O generation pathway and oxidation behavior remain obscure. Employing an Fe-N-C catalyst with a typical Fe-N4 moiety to activate peroxymonosulfate (PMS), we demonstrate that generating FeIV =O is mediated by an Fe-N-C-PMS* complex-a well-recognized nonradical species for induction of electron-transfer oxidation-and we determined that adjacent Fe sites with a specific Fe1 -Fe1 distance are required. After the Fe atoms with an Fe1 -Fe1 distance <4 Šare PMS-saturated, Fe-N-C-PMS* formed on Fe sites with an Fe1 -Fe1 distance of 4-5 Šcan coordinate with the adjacent FeII -N4 , forming an inter-complex with enhanced charge transfer to produce FeIV =O. FeIV =O enables the Fenton-like system to efficiently oxidize various pollutants in a substrate-specific, pH-tolerant, and sustainable manner, where its prominent contribution manifests for pollutants with higher one-electron oxidation potential.

5.
Environ Sci Technol ; 56(19): 14019-14029, 2022 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-36062466

RESUMEN

In electrochemical advanced oxidation processes (EAOPs), the rate-limiting step is the mass transfer of pollutants to the electrodes due to the limited active surface areas. To this end, we established a three-dimensional (3D) EAOP system by coupling conventional graphite electrodes with dispersed carbon nanotubes (CNTs). The electrodes (particularly the anode) induced electric field spontaneously polarized CNTs into dispersed reactive particle electrodes (CNT-PEs) in the solution, which remarkably promoted electrochemical activation of peroxydisulfate (PDS) to generate surface CNT-PDS* complexes and surface-bound radicals (SBRs). Based on the excited potential (ECNT-PEs) at different positions in the 3D electric field, CNT-PEs were activated into three states. (i) ECNT-PEs < Eorganic, CNT-PEs are chemically inert toward DCP oxidation; (ii) Eorganic < ECNT-PEs < Ewater, CNT-PEs will oxidize DCP via an electron-transfer process (ETP); (iii) ECNT-PEs > Ewater, both CNT-PDS* complexes and the anode will oxidize water to produce SBRs. Thus, DCP could be oxidized by CNT-PDS* complexes via ETP to form polychlorophenols on the CNT surface, causing rapid deactivation of the micro-electrodes. In contrast, SBRs attack DCP directly into chloride ions and hydroxylated products, maintaining the surface cleanliness and activity of CNT-PEs for long-term operations.


Asunto(s)
Contaminantes Ambientales , Grafito , Nanotubos de Carbono , Cloruros , Electrodos , Nanotubos de Carbono/química , Oxidación-Reducción , Agua
6.
BMC Med Imaging ; 22(1): 123, 2022 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-35810273

RESUMEN

OBJECTIVES: Accurate contouring of the clinical target volume (CTV) is a key element of radiotherapy in cervical cancer. We validated a novel deep learning (DL)-based auto-segmentation algorithm for CTVs in cervical cancer called the three-channel adaptive auto-segmentation network (TCAS). METHODS: A total of 107 cases were collected and contoured by senior radiation oncologists (ROs). Each case consisted of the following: (1) contrast-enhanced CT scan for positioning, (2) the related CTV, (3) multiple plain CT scans during treatment and (4) the related CTV. After registration between (1) and (3) for the same patient, the aligned image and CTV were generated. Method 1 is rigid registration, method 2 is deformable registration, and the aligned CTV is seen as the result. Method 3 is rigid registration and TCAS, method 4 is deformable registration and TCAS, and the result is generated by a DL-based method. RESULTS: From the 107 cases, 15 pairs were selected as the test set. The dice similarity coefficient (DSC) of method 1 was 0.8155 ± 0.0368; the DSC of method 2 was 0.8277 ± 0.0315; the DSCs of method 3 and 4 were 0.8914 ± 0.0294 and 0.8921 ± 0.0231, respectively. The mean surface distance and Hausdorff distance of methods 3 and 4 were markedly better than those of method 1 and 2. CONCLUSIONS: The TCAS achieved comparable accuracy to the manual delineation performed by senior ROs and was significantly better than direct registration.


Asunto(s)
Aprendizaje Profundo , Neoplasias del Cuello Uterino , Algoritmos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Especies Reactivas de Oxígeno , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/radioterapia
7.
J Appl Clin Med Phys ; 23(2): e13470, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34807501

RESUMEN

OBJECTIVES: Because radiotherapy is indispensible for treating cervical cancer, it is critical to accurately and efficiently delineate the radiation targets. We evaluated a deep learning (DL)-based auto-segmentation algorithm for automatic contouring of clinical target volumes (CTVs) in cervical cancers. METHODS: Computed tomography (CT) datasets from 535 cervical cancers treated with definitive or postoperative radiotherapy were collected. A DL tool based on VB-Net was developed to delineate CTVs of the pelvic lymph drainage area (dCTV1) and parametrial area (dCTV2) in the definitive radiotherapy group. The training/validation/test number is 157/20/23. CTV of the pelvic lymph drainage area (pCTV1) was delineated in the postoperative radiotherapy group. The training/validation/test number is 272/30/33. Dice similarity coefficient (DSC), mean surface distance (MSD), and Hausdorff distance (HD) were used to evaluate the contouring accuracy. Contouring times were recorded for efficiency comparison. RESULTS: The mean DSC, MSD, and HD values for our DL-based tool were 0.88/1.32 mm/21.60 mm for dCTV1, 0.70/2.42 mm/22.44 mm for dCTV2, and 0.86/1.15 mm/20.78 mm for pCTV1. Only minor modifications were needed for 63.5% of auto-segmentations to meet the clinical requirements. The contouring accuracy of the DL-based tool was comparable to that of senior radiation oncologists and was superior to that of junior/intermediate radiation oncologists. Additionally, DL assistance improved the performance of junior radiation oncologists for dCTV2 and pCTV1 contouring (mean DSC increases: 0.20 for dCTV2, 0.03 for pCTV1; mean contouring time decrease: 9.8 min for dCTV2, 28.9 min for pCTV1). CONCLUSIONS: DL-based auto-segmentation improves CTV contouring accuracy, reduces contouring time, and improves clinical efficiency for treating cervical cancer.


Asunto(s)
Aprendizaje Profundo , Neoplasias del Cuello Uterino , Algoritmos , Femenino , Humanos , Órganos en Riesgo , Planificación de la Radioterapia Asistida por Computador , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/radioterapia
8.
J Cell Physiol ; 234(10): 18837-18848, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30916406

RESUMEN

The aberrant expression of long noncoding RNAs (lncRNAs) has drawn increasing attention in the field of hepatocellular carcinoma (HCC) biology. In the present study, we obtained the expression profiles of lncRNAs, microRNAs (miRNAs), and messenger RNAs (mRNAs) in 371 HCC tissues and 50 normal tissues from The Cancer Genome Atlas (TCGA) and identified hepatocarcinogenesis-specific differentially expressed genes (DEGs, log fold change ≥ 2, FDR < 0.01), including 753 lncRNAs, 97 miRNAs, and 1,535 mRNAs. Because the specific functions of lncRNAs are closely related to their intracellular localizations and because the cytoplasm is the main location for competitive endogenous RNA (ceRNA) action, we analyzed not only the interactions among these DEGs but also the distributions of lncRNAs (cytoplasmic, nuclear or both). Then, an HCC-associated deregulated ceRNA network consisting of 37 lncRNAs, 10 miRNAs, and 26 mRNAs was constructed after excluding those lncRNAs located only in the nucleus. Survival analysis of this network demonstrated that 15 lncRNAs, 3 miRNAs, and 16 mRNAs were significantly correlated with the overall survival of HCC patients (p < 0.01). Through multivariate Cox regression and lasso analysis, a risk score system based on 13 lncRNAs was constructed, which showed good discrimination and predictive ability for HCC patient survival time. This ceRNA network-construction approach, based on lncRNA distribution, not only narrowed the scope of target lncRNAs but also provided specific candidate molecular biomarkers for evaluating the prognosis of HCC, which will help expand our understanding of the ceRNA mechanisms involved in the early development of HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Citoplasma/metabolismo , Progresión de la Enfermedad , Redes Reguladoras de Genes , Neoplasias Hepáticas/genética , ARN Largo no Codificante/genética , Regulación Neoplásica de la Expresión Génica , Ontología de Genes , Humanos , Estimación de Kaplan-Meier , Modelos Lineales , Neoplasias Hepáticas/patología , MicroARNs/genética , MicroARNs/metabolismo , Pronóstico , ARN Largo no Codificante/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Riesgo , Análisis de Supervivencia
9.
Int J Neurosci ; 129(11): 1045-1052, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31215295

RESUMEN

Objective: It is challenging for neurosurgeons to perform surgeries on patients without detectable structural lesions. Therefore, this retrospective study aimed to explore the outcome of stereo-electroencephalography (SEEG) in suspicious areas guided by magnetoencephalography (MEG)-magnetic resonance imaging (MRI) reconstruction in MRI-negative epilepsy patients. Methods: This study included 47 patients with negative-MRI epilepsy. Seizure outcome at 24 months was assessed using a modified Engel's classification. Accordingly, class I and II were considered favorable outcomes, whereas classes III and IV were unfavorable. Furthermore, patients were classified into a consistent group if the results of MEG and SEEG indicated the same area of the brain. The relationship between surgical outcome and the concordance of MEG and SEEG was analyzed. Results: A complete seizure-free condition was achieved in 22 (47%) patients. Sex, handedness, age and duration of illness were not significantly associated with seizure-free outcome (p = .187 [Pearson chi-squared test]). The number of patients with favorable outcome (Engle I and II) was as high as 68% at the time of follow-up. Furthermore, more seizure-free patients were found in the SEEG and MEG consistent group. Conclusions: SEEG is a valuable tool in the pre-evaluation for resective epilepsy surgery, particularly in negative-MRI epilepsy patients; MEG greatly facilitates localization for SEEG electrode implantation. However, none of these tools are absolutely sensitive and reliable; therefore, collecting as much information as possible is necessary to achieve satisfactory results in epilepsy surgery.


Asunto(s)
Electrocorticografía/métodos , Epilepsia/diagnóstico , Epilepsia/cirugía , Magnetoencefalografía/métodos , Procedimientos Neuroquirúrgicos/métodos , Evaluación de Resultado en la Atención de Salud , Adolescente , Adulto , Niño , Electrocorticografía/normas , Epilepsia/fisiopatología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
10.
Biochem Biophys Res Commun ; 495(2): 1908-1914, 2018 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-29242154

RESUMEN

Diffuse panbronchiolitis critical region 1 (DPCR1) is located in the major histocompatibility complex (MHC) class I. It was reported to be downregulated in invasive pituitary adenoma compared with that in non-invasive tumors, but upregulated in the precursor of gastric carcinogenesis. However, the direct effect of DPCR1 on cancer cells has rarely been reported, and the role DPCR1 in pancreatic ductal adenocarcinoma (PDAC) remains unclear. The clinical sample validation and public data analysis of the present study demonstrated that DPCR1 was upregulated markedly in PDAC and this high expression was negatively correlated with the patient prognosis. Functionally, knocking down DPCR1 in PDAC cell lines inhibited cell proliferation, migration and invasion in vitro. Tumor xenograft experiments further showed that suppression of DPCR1 inhibited tumor growth in vivo. In addition, the results of RNA deep sequencing and qRT-PCR assay showed that DPCR1 participated in PADC progression by regulating nuclear factor-kappa B signaling pathway, suggesting that it might be a novel oncogene in tumor progression and a potential therapeutic target in PDAC as well.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Proteínas/metabolismo , Adulto , Animales , Carcinoma Ductal Pancreático/mortalidad , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , China/epidemiología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones Endogámicos C57BL , Mucinas , Invasividad Neoplásica , Neoplasias Pancreáticas/mortalidad , Prevalencia , Medición de Riesgo , Tasa de Supervivencia , Regulación hacia Arriba
11.
J Comput Assist Tomogr ; 42(5): 714-720, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30015796

RESUMEN

OBJECTIVE: This study aimed to evaluate the prediction roles of clinical plus imaging features and multidetector computed tomography (MDCT) texture analysis in preoperative risk grade classification of small bowel (SB) gastrointestinal stromal tumors (GISTs). METHODS: This study included 213 SB GIST patients. Clinical features and MDCT imaging findings were reviewed. Tumor risk stratifications were determined according to modified National Institutes of Health criteria. Random forest models were performed to evaluate the correlation of risk stratification. RESULTS: The model of clinical plus imaging findings showed an area under receiver operating characteristic curve (AUC) of 92.0%. The AUC of texture analysis based on MDCT portal phase was 93.3%, without statistical difference from that of clinical plus imaging model (P = 0.378). The AUC of the model combined clinical plus imaging features and MDCT texture analysis was 94.3%, which was significantly higher than the AUC of clinical imaging model (P = 0.042). CONCLUSION: Texture analysis may become an important comprehensive tool for preoperative risk stratification of SB GISTs.


Asunto(s)
Tumores del Estroma Gastrointestinal/diagnóstico por imagen , Tumores del Estroma Gastrointestinal/patología , Procesamiento de Imagen Asistido por Computador/métodos , Intestino Delgado/diagnóstico por imagen , Tomografía Computarizada Multidetector/métodos , Cuidados Preoperatorios/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Intestino Delgado/patología , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Adulto Joven
12.
Clin Exp Hypertens ; 40(1): 39-48, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29072489

RESUMEN

Increased short-term blood pressure variability (BPV) is strongly correlated with target organ damage. However, the molecular mechanisms underlying abnormal BPV-induced organ damage and effective therapeutic targets are poorly understood. The purpose of this study was to investigate the effects of losartan on vasomotor function and canonical transient receptor potential (TRPC) channels in the aortas of rats with arterial pressure lability induced by sinoaortic denervation (SAD). SAD was performed in male Sprague-Dawley rats at the age of 10 weeks. The experiment included sham-operated (Sham), SAD, and losartan-treated SAD (SAD+Los) groups. After 8 weeks of treatment, hemodynamic parameters were measured via catheterization, thoracic aortic vasomotor functions were evaluated using a physiological vascular ring tension recording system, and TRPC1 and 6 mRNA and protein expression levels in the endothelial cells (ECs) and smooth muscle cells (SMCs) of the thoracic aorta were determined via reverse transcription polymerase chain reaction (RT-PCR) and Western-blotting, respectively. Compared with Sham rats, SAD rats exhibited significantly increased BPV, enhanced norepinephrine-induced aortic contraction, and attenuated acetylcholine-induced aortic relaxation. Both the mRNA and the protein expression levels of TRPC1 and 6 were significantly downregulated in the ECs and upregulated in the SMCs of the thoracic aortas of SAD rats. Losartan treatment prevented these SAD-induced changes. In conclusion, losartan efficiently prevented vasomotor function impairment in SAD rats by reducing BPV and regulating TRPC1 and 6 expression levels.


Asunto(s)
Antihipertensivos/farmacología , Aorta Torácica/fisiopatología , Presión Sanguínea/efectos de los fármacos , Losartán/farmacología , Canales Catiónicos TRPC/metabolismo , Acetilcolina/farmacología , Animales , Aorta Torácica/efectos de los fármacos , Aorta Torácica/inervación , Aorta Torácica/metabolismo , Desnervación , Células Endoteliales/metabolismo , Hipertensión/tratamiento farmacológico , Hipertensión/metabolismo , Masculino , Contracción Muscular , Relajación Muscular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiopatología , Norepinefrina/farmacología , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Canales Catiónicos TRPC/genética , Vasoconstricción/efectos de los fármacos , Vasoconstrictores/farmacología , Vasodilatación/efectos de los fármacos , Vasodilatadores/farmacología
13.
Small ; 12(29): 3995-4006, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27345304

RESUMEN

Hypoxia, which has been well established as a key feature of the tumor microenvironment, significantly influences tumor behavior and treatment response. Therefore, imaging for tumor hypoxia in vivo is warranted. Although some imaging modalities for detecting tumor hypoxia have been developed, such as magnetic resonance imaging, positron emission tomography, and optical imaging, these technologies still have their own specific limitations. As computed tomography (CT) is one of the most useful imaging tools in terms of availability, efficiency, and convenience, the feasibility of using a hypoxia-sensitive nanoprobe (Au@BSA-NHA) for CT imaging of tumor hypoxia is investigated, with emphasis on identifying different levels of hypoxia in two xenografts. The nanoprobe is composed of Au nanoparticles and nitroimidazole moiety which can be electively reduced by nitroreductase under hypoxic condition. In vitro, Au@BSA-NHA attain the higher cellular uptake under hypoxic condition. Attractively, after in vivo administration, Au@BSA-NHA can not only monitor the tumor hypoxic environment with CT enhancement but also detect the hypoxic status by the degree of enhancement in two xenograft tumors with different hypoxic levels. The results demonstrate that Au@BSA-NHA may potentially be used as a sensitive CT imaging agent for detecting tumor hypoxia.


Asunto(s)
Medios de Contraste/química , Tomografía Computarizada por Rayos X/métodos , Hipoxia Tumoral/fisiología , Animales , Línea Celular Tumoral , Fibrosarcoma/diagnóstico por imagen , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Pancreáticas/diagnóstico por imagen
14.
J Cardiovasc Pharmacol ; 67(5): 418-26, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26828322

RESUMEN

BACKGROUND: Helix B surface peptide (HBSP), a newly developed tissue-protective erythropoietin derivative, has beneficial effects on myocardial ischemia. This study aimed to investigate the cardio-protective effects of HBSP against hypoxia/reoxygenation (H/R) injury and its possible mechanism. METHODS: A rat-derived cardiomyocyte cell line (H9C2 cells) were established and pretreated with HBSP. The pretreated primary cultures were subjected to H/R and monitored for cell viability using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. Intracellular reactive oxygen species (ROS) levels, apoptosis, and mitochondrial membrane potential (ΔΨm) were detected by flow cytometry. The expression of cytochrome C and Bcl-2 family proteins, as well as the activities of caspases 3 and 9 were determined by Western blot analysis and a colorimetric method, respectively. RESULTS: HBSP reduced apoptotic cells in cardiomyocytes subjected to H/R. In HBSP-treated cardiomyocytes, the H/R-induced mitochondrial ROS production, ΔΨm collapse, and cytochrome C release from mitochondria to the cytosol significantly decreased. Moreover, HBSP inhibited the activation of caspases 9 and 3, as well as the alteration of Bcl-2 family proteins, which were induced by H/R. CONCLUSIONS: These results indicated that HBSP has protective effects against H/R-induced apoptosis by regulating the mitochondrial pathway. This mechanism involves inhibiting mitochondrial ROS generation, inhibiting caspase-3 activity, reducing ΔΨm collapse, reducing cytochrome release, and balancing anti and proapoptotic Bcl-2 family proteins.


Asunto(s)
Apoptosis/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Eritropoyetina/farmacología , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Miocitos Cardíacos/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Animales , Caspasas/metabolismo , Citocromos c/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias , Daño por Reperfusión Miocárdica/fisiopatología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Especies Reactivas de Oxígeno/metabolismo
15.
Cardiology ; 134(2): 109-17, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26938973

RESUMEN

OBJECTIVE: This study explores the effects of helix B surface peptide (HBSP) on myocardial infarct size (IS), cardiac function, cardiomyocyte apoptosis and oxidative stress damage in mouse hearts subjected to myocardial ischemia-reperfusion injury (MIRI) and also the mechanisms underlying the effects. METHOD: Male adult mice were subjected to 45 min of ischemia followed by 2 h of reperfusion; 5 min before the reperfusion, they were treated with HBSP or vehicle. MIRI-induced IS, cardiomyocyte apoptosis and cardiac functional impairment were determined and compared. Western blot analysis was then conducted to elucidate the mechanism of HBSP after treatment. RESULTS: HBSP administration before reperfusion significantly reduced the myocardial IS, decreased cardiomyocyte apoptosis, reduced the activities of superoxide dismutase and malondialdehyde and partially preserved heart function. As demonstrated by the Western blot analysis, HBSP after treatment upregulated Akt/GSK-3ß/ERK and STAT-3 phosphorylation; these inhibitors, in turn, weakened the beneficial effects of HBSP. CONCLUSION: HBSP plays a protective role in MIRI in mice by inhibiting cardiomyocyte apoptosis, reducing the MIRI-induced IS, oxidative stress and improving the heart function after MIRI. The mechanism underlying these effects of HBSP is related to the activation of the RISK (reperfusion injury salvage kinase, Akt/GSK-3ß/ERK) and SAFE (STAT-3) pathways.


Asunto(s)
Apoptosis/efectos de los fármacos , Eritropoyetina/administración & dosificación , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Miocitos Cardíacos/efectos de los fármacos , Fragmentos de Péptidos/administración & dosificación , Transducción de Señal/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Masculino , Ratones , Fosforilación , Función Ventricular/efectos de los fármacos
17.
Acta Derm Venereol ; 96(5): 684-8, 2016 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-26775671

RESUMEN

The aim of this study was to evaluate the effectiveness of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) for the treatment of vulvar lichen sclerosus (VLS) and compare its effectiveness with that of clobetasol propionate. Four sessions of topical photodynamic therapy (PDT) were administered at 2-week intervals (n = 20). Clobetasol propionate (0.05%) was used daily for 8 weeks (n = 20). The rate of complete response in the PDT group (14/20) was double that of the clobetasol propionate group (7/20) (p < 0.05, 2 = 4.912). Horizontal visual analogue scores indicated that PDT was more effective than clobetasol propionate. Pain intensity numeric rating scale values for PDT were between 3.05 and 4.45. One month after the final session of PDT, only one patient relapsed and all 7 patients in clobetasol propionate group relapsed. ALA-PDT is a well-tolerated and effective option for the treatment of VLS.


Asunto(s)
Ácido Aminolevulínico/uso terapéutico , Clobetasol/uso terapéutico , Glucocorticoides/uso terapéutico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/uso terapéutico , Liquen Escleroso Vulvar/tratamiento farmacológico , Femenino , Humanos , Persona de Mediana Edad , Dimensión del Dolor , Estudios Prospectivos , Resultado del Tratamiento
19.
Curr Med Imaging ; 20: e260423216201, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37170973

RESUMEN

Introduction: The objective of this study was to describe the CT and MRI features of sclerosing angiomatoid nodular transformation (SANT) of the spleen with pathologic correlation. Materials and Methods: Ten patients with surgically resected and pathologically confirmed SANTs were included. Clinical history was reviewed, and gross pathologic, histologic, and immunohistochemical findings were recorded. CT and MRI examinations were evaluated by two radiologists. Results: Patients included seven men and three women, with a mean age of 42.9±16.7 years. Pathologic features of SANTs involved multiple angiomatous nodules in a radiating pattern with a central stellate fibrous scar and evidence of hemosiderin deposition. 9 cases showed a lobulated demarcated margin, 8 cases a slight hypoattenuating, 1 isoattenuating, and 1 case with two lesions demonstrated a slight hyperattenuating margin, respectively. Multiple scattered punctate calcifications were involved in 2 cases. 5 cases manifested hypointensity on in-phase imaging, 1 iso-intensity, and 4 iso-hypointensity on out-of-phase imaging. Progressive and centripetal enhancement were exhibited in 10 cases, spoke-wheel pattern in 3 cases, and nodular enhancement in 4 cases, respectively. The central fibrous scar was identified in 8 cases during delayed enhancement. Conclusion: Characteristics of SANTs on CT/MRI reflected the underlying pathology. Hypointensity on DWI and T2WI, and change of signal on T1 chemicalshift imaging were found to be due to hemosiderin deposition and fibrous tissue. Typical feature was a solitary, round, lobulated mass with a fibrous scar. Progressive and centripetal enhancement, spoke-wheel pattern, nodular enhancement, and delayed enhancement of central fibrous scar were observed.


Asunto(s)
Histiocitoma Fibroso Benigno , Bazo , Masculino , Humanos , Femenino , Adulto , Persona de Mediana Edad , Bazo/diagnóstico por imagen , Bazo/patología , Histiocitoma Fibroso Benigno/diagnóstico por imagen , Histiocitoma Fibroso Benigno/cirugía , Histiocitoma Fibroso Benigno/patología , Cicatriz/patología , Hemosiderina , Tomografía Computarizada por Rayos X
20.
Sci Total Environ ; 927: 171689, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38492599

RESUMEN

Sulfur plays an essential role in agricultural production, but few studies have been reported on how sulfur simultaneously impacts the transformation of cadmium (Cd) and arsenic (As) in the soil-rice system. This research selected two soils co-contaminated with both Cd and As, varying in acidity and alkalinity levels, to study the impacts of elemental sulfur (S) and calcium sulfate (CaSO4) on the migration and accumulation of Cd and As by rice. Results indicated that two types of sulfur had a substantial (P < 0.05) impact on decreasing the contents of Cd (28.3-50.4 %) and As (20.1-38.6 %) in brown rice in acidic and alkaline soils. They also increased rice biomass (29.3-112.8 %) and reduced Cd transport coefficient (27.2-45.6 %) significantly (P < 0.05). Notably, sulfur augmented the generation of iron plaque on rice root surfaces, which increased the fixation of Cd (17.6-61.0 %) and As (14.0-45.9 %). SEM-EDS results also indicated that the rice root surface exhibited significant enrichment of Fe, Cd, and As. The mechanism of simultaneous Cd and As immobilization by sulfur application was mainly ascribed to the contribution of iron plaque. Additionally, sulfur reduced the contents of Cd and As in soil porewater and promoted the transformation of As(III) to As(V) to reduce the toxicity of As. The K-edge XAFS of As in iron plaque also confirmed that sulfur application significantly promoted As(III) oxidation. Sulfur also promoted the activities of antioxidant enzymes and the contents of NPT, GSH, and PCs in rice plants. In general, this study establishes a foundation for sulfur to lower As and Cd bioavailability in paddy soils, enhance iron plaque and rice resistance, and reduce heavy metal accumulation.


Asunto(s)
Arsénico , Cadmio , Hierro , Oryza , Contaminantes del Suelo , Suelo , Azufre , Suelo/química
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