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1.
J Neurooncol ; 167(1): 123-132, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38300388

RESUMEN

BACKGROUND: Magnetic resonance imaging (MRI) guided adaptive radiotherapy (MRgART) has gained increasing attention, showing clinical advantages over conventional radiotherapy. However, there are concerns regarding online target delineation and modification accuracy. In our study, we aimed to investigate the accuracy of brain metastases (BMs) contouring and its impact on dosimetry in 1.5 T MRI-guided online adaptive fractionated stereotactic radiotherapy (FSRT). METHODS: Eighteen patients with 64 BMs were retrospectively evaluated. Pre-treatment 3.0 T MRI scans (gadolinium contrast-enhanced T1w, T1c) and initial 1.5 T MR-Linac scans (non-enhanced online-T1, T2, and FLAIR) were used for gross target volume (GTV) contouring. Five radiation oncologists independently contoured GTVs on pre-treatment T1c and initial online-T1, T2, and FLAIR images. We assessed intra-observer and inter-observer variations and analysed the dosimetry impact through treatment planning based on GTVs generated by online MRI, simulating the current online adaptive radiotherapy practice. RESULTS: The average Dice Similarity Coefficient (DSC) for inter-observer comparison were 0.79, 0.54, 0.59, and 0.64 for pre-treatment T1c, online-T1, T2, and FLAIR, respectively. Inter-observer variations were significantly smaller for the 3.0 T pre-treatment T1c than for the contrast-free online 1.5 T MR scans (P < 0.001). Compared to the T1c contours, the average DSC index of intra-observer contouring was 0.52‒0.55 for online MRIs. For BMs larger than 3 cm3, visible on all image sets, the average DSC indices were 0.69, 0.71 and 0.64 for online-T1, T2, and FLAIR, respectively, compared to the pre-treatment T1c contour. For BMs < 3 cm3, the average visibility rates were 22.3%, 41.3%, and 51.8% for online-T1, T2, and FLAIR, respectively. Simulated adaptive planning showed an average prescription dose coverage of 63.4‒66.9% when evaluated by ground truth planning target volumes (PTVs) generated on pre-treatment T1c, reducing it from over 99% coverage by PTVs generated on online MRIs. CONCLUSIONS: The accuracy of online target contouring was unsatisfactory for the current MRI-guided online adaptive FSRT. Small lesions had poor visibility on 1.5 T non-contrast-enhanced MR-Linac images. Contour inaccuracies caused a one-third drop in prescription dose coverage for the target volume. Future studies should explore the feasibility of contrast agent administration during daily treatment in MRI-guided online adaptive FSRT procedures.


Asunto(s)
Neoplasias Encefálicas , Radiocirugia , Humanos , Estudios Retrospectivos , Planificación de la Radioterapia Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/radioterapia
2.
J Appl Clin Med Phys ; 25(4): e14258, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38175960

RESUMEN

PURPOSE: We aimed to perform the commissioning and clinical evaluation of myQA SRS detector array for patient-specific quality assurance (PSQA) of stereotactic radiosurgery (SRS)/ stereotactic body radiotherapy (SBRT) plans. METHODS: To perform the commissioning of myQA SRS, its dose linearity, dose-rate dependence, angular dependence, and field-size dependence were investigated. Ten SBRT plans were selected for clinical evaluation: 1) Common clinical deviations based on the original SBRT plan (Plan0), including multileaf collimator (MLC) positioning deviation and treatment positioning deviation were introduced. 2) Compared the performance of the myQA SRS and a high-resolution EPID dosimetry system in PSQA measurement for the SBRT plans. Evaluation parameters include gamma passing rate (GPR) and distance-to-agreement (DTA) pass rate (DPR). RESULTS: The dose linearity, angle dependence, and field-size dependence of myQA SRS system exhibit excellent performance. The myQA SRS is highly sensitive in the detection of MLC deviations. The GPR of (3%/1 mm) decreases from 90.4% of the original plan to 72.7%/62.9% with an MLC outward/inward deviation of 3 mm. Additionally, when the setup error deviates by 1 mm in the X, Y, and Z directions with the GPR of (3%/1 mm) decreasing by an average of -20.9%, -25.7%, and -24.7%, respectively, and DPR (1 mm) decreasing by an average of -33.7%, -32.9%, and -29.8%. Additionally, the myQA SRS has a slightly higher GPR than EPID for PSQA, However, the difference is not statistically significant with the GPR of (3%/1 mm) of (average 90.4%% vs. 90.1%, p = 0.414). CONCLUSION: Dosimetry characteristics of the myQA SRS device meets the accuracy and sensitivity requirement of PSQA for SRS/SBRT treatment. The dose rate dependence should be adequately calibrated before its application and a more stringent GPR (3%/1 mm) evaluation criterion is suggested when it is used for SRS/SBRT QA.


Asunto(s)
Radiocirugia , Radioterapia de Intensidad Modulada , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Fantasmas de Imagen , Radiometría
3.
FASEB J ; 36(9): e22473, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35976172

RESUMEN

Although the role of serine racemase (SR) in neuropsychiatric disorders has been extensively studied, its role in cell proliferation and differentiation remains unclear. Deletion of Srr, the encoding gene for SR, has been shown to reduce dendritic arborization and dendritic spine density in the brains of adult mice, whereas increased SR levels have been associated with differentiation in cell cultures. Previously, we demonstrated that valproic acid induces differentiation in the N2A neuroblastoma cell line, and that this differentiation is associated with increased SR expression. These observations suggest that SR may have a role in cell proliferation and differentiation. We herein found that both valproic acid and all-trans retinoic acid induced N2A differentiation. In contrast, knockdown of SR reduced levels of differentiation, increased N2A proliferation, promoted cell cycle entry, and modulated expression of cell cycle-related proteins. To further evaluate the effects of SR expression on cell proliferation and differentiation, we used an in vivo model of neuroblastoma in nude mice. N2A cells stably expressing scramble shRNA (Srrwt -N2A) or specific Srr shRNA (Srrkd -N2A) were subcutaneously injected into nude mice. The weights and volumes of Srrwt -N2A-derived tumors were lower than Srrkd -N2A-derived tumors. Furthermore, Srrwt -N2A-derived tumors were significantly mitigated by intraperitoneal injection of valproic acid, whereas Srrkd -N2A-derived tumors were unaffected. Taken together, our findings demonstrate for the first time that alterations in SR expression determine the transition between proliferation and differentiation in neural progenitor cells. Thus, in addition to its well-established roles in neuropsychiatric disorders, our study has highlighted a novel role for SR in cell proliferation and differentiation.


Asunto(s)
Neuroblastoma , Ácido Valproico , Animales , Diferenciación Celular , Proliferación Celular , Ratones , Ratones Desnudos , Neuroblastoma/genética , Neuroblastoma/metabolismo , ARN Interferente Pequeño/genética , Racemasas y Epimerasas , Serina , Ácido Valproico/farmacología
4.
J Appl Clin Med Phys ; 24(11): e14097, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37438966

RESUMEN

PURPOSE: This study aimed to assess the effects of bladder filling during cervical cancer radiotherapy on target volume and organs at risk (OARs) dose based on daily computed tomography (daily-CT) images and provide bladder-volume-based dose prediction models. METHODS: Nineteen patients (475 daily-CTs) comprised the study group, and five patients comprised the validation set (25 daily-CTs). Target volumes and OARs were delineated on daily-CT images and the treatment plan was recalculated accordingly. The deviation from the planning bladder volume (DVB), the correlation between DVB and clinical (CTV)/planning (PTV) target volume in terms of prescribed dose coverage, and the relationship of small bowel volume and bladder dose with the ratio of bladder volume (RVB) were analyzed. RESULTS: In all cases, the prescribed dose coverage in the CTV was >95% when DVB was <200 cm3 , whereas that in the PTV was >95% when RVB was <160%. The ratio of bladder V45 Gy to the planning bladder V45 Gy (RBV45 ) exhibited a negative linear relationship with RVB (RBV45  = -0.18*RVB + 120.8; R2  = 0.80). Moreover, the ratio of small bowel volume to planning small bowel volume (RVS) exhibited a negative linear relationship with RVB (RVS = -1.06*RVB +217.59; R2  = 0.41). The validation set results showed that the linear model predicted well the effects of bladder volume changes on target volume coverage and bladder dose. CONCLUSIONS: This study assessed dosimetry and volume effects of bladder filling on target and OARs based on daily-CT images. We established a quantitative relationship between these parameters, providing dose prediction models for cervical cancer radiotherapy.


Asunto(s)
Radioterapia de Intensidad Modulada , Neoplasias del Cuello Uterino , Femenino , Humanos , Vejiga Urinaria/diagnóstico por imagen , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/radioterapia , Tomografía Computarizada por Rayos X , Radioterapia de Intensidad Modulada/métodos , Órganos en Riesgo
5.
Zhongguo Zhong Yao Za Zhi ; 48(14): 3730-3735, 2023 Jul.
Artículo en Zh | MEDLINE | ID: mdl-37475064

RESUMEN

Artemisia stolonifera is a relative of A. argyi. The two species are difficult to be distinguished due to the similarity in leaf shape and have even less distinctive features after processing. This study aims to establish a method to quickly distinguish between them. At the same time, we examined the reasonability and applicability of the specific polymerase chain reaction(PCR) method. The C/T single nucleotide polymorphism was detected at the position 202 of the sequence, based on which specific primers were designed to identify these two species. The PCR with the specific primer JNC-F and the universal primer ITS3R produced a specific band at 218 bp for A. argyi and no band for A. stolonifera, which can be used to detect at least 3% of A. argyi samples mixed in A. stolonifera samples. The PCR with the specific primer KY-F and the universal primer ITS3R produced a specific band at 218 bp for A. stolonifera and no band for A. argyi, which can be used to detect at least 5% of A. stolonifera samples mixed with A. argyi. The limit of detection of the established method was 5 ng DNA. The established PCR method can accurately distinguish between A. stolonifera and A. argyi, which provides an experimental basis for the quality control of A. stolonifera and determines whether the herbs are adulterated.


Asunto(s)
Artemisia , Artemisia/genética , Tricomas , Reacción en Cadena de la Polimerasa , Técnicas de Amplificación de Ácido Nucleico , Hojas de la Planta/genética
6.
Clin Immunol ; 245: 109169, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36332815

RESUMEN

BACKGROUND: Sepsis is a life-threatening condition. The incidence of severe sepsis is increasing. Sepsis is often complicated with organ dysfunctions. Cyclic helix B peptide (CHBP) is a peptide derivant of erythropoietin with powerful tissue-protective efficacies. However, the role of CHBP in sepsis-induced injury remains unclear. MATERIAL AND METHODS: Lyso-phosphatidylserine (LPS) was used to induce sepsis in human pulmonary microvascular endothelial cells (HPMECs). Cell growth was detected using Cell Counting Kit-8. Cell permeability was measured using fluorescein isothiocyanate (FITC)-dextran. Cecal ligation and puncture (CLP) method was applied to induce sepsis and CHBP was provided to test its efficacy. Western blot assays were used to evaluate gene expression. RESULTS: Administration of CHBP ameliorated LPS-induced injury in HPMECs dose-dependently. Administration of CHBP decreased the permeability of LPS-treated HPMEC cells in a same way as well. Furthermore, we identified that recombinant CHBP protein (Re-CHBP) ameliorated CLP-induced injury in vivo. Finally, we found that administration of NF-κB activator, TNF-α, abolished the function of Re-CHBP in LPS-treated HPMEC cells. CONCLUSION: CHBP ameliorated sepsis-induced injury dose dependently both in vitro and in vivo through decreasing the permeability of HPMEC cells via suppressing NF-κB signaling and inflammation. Present findings highlight the importance of CHBP/NF-κB signaling in septic injury and provide new insights into therapeutic strategies for sepsis-induced injury.


Asunto(s)
FN-kappa B , Sepsis , Humanos , FN-kappa B/metabolismo , Lipopolisacáridos , Péptidos Cíclicos/uso terapéutico , Células Endoteliales , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Sepsis/metabolismo
7.
Acta Oncol ; 61(11): 1417-1424, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36305424

RESUMEN

PURPOSE: To develop an advanced deep convolutional neural network (DCNN) architecture to generate synthetic CT (SCT) images from MR images for intensity-modulated proton therapy (IMPT) treatment planning of nasopharyngeal cancer (NPC) patients. METHODS: T1-weighted MR images and paired CT (PCT) images were obtained from 206 NPC patients. For each patient, deformable image registration was performed between MR and PCT images to create an MR-CT image pair. Thirty pairs were randomly chosen as the independent test set and the remaining 176 pairs (14 for validation and 162 for training) were used to build two conditional generative adversarial networks (GANs): 1) GAN3D: using a 3D U-net enhanced with residual connections and attentional mechanism as the generator and 2) GAN2D: using a 2D U-net as the generator. For each test patient, SCT images were generated using the generators with the MR images as input and were compared with respect to the corresponding PCT image. A clinical IMPT plan was created and optimized on the PCT image. The dose was recalculated on the SCT images and compared with the one calculated on the PCT image. RESULTS: The mean absolute errors (MAEs) between the PCT and SCT, within the body, were (64.89 ± 5.31) HU and (64.31 ± 4.61) HU for the GAN2D and GAN3D. Within the high-density bone (HU > 600), the GAN3D achieved a smaller MAE compared with the GAN2D (p < 0.001). Within the body, the absolute point dose deviation was reduced from (0.58 ± 1.61) Gy for the GAN2D to (0.47 ± 0.94) Gy for the GAN3D. The (3 mm/3%) gamma passing rates were above 97.32% for all SCT images. CONCLUSIONS: The SCT images generated using GANs achieved clinical acceptable dosimetric accuracy for IMPT of NPC patients. Using advanced DCNN architecture design, such as residual connections and attention mechanism, SCT image quality was further improved and resulted in a small dosimetric improvement.


Asunto(s)
Neoplasias Nasofaríngeas , Terapia de Protones , Radioterapia de Intensidad Modulada , Humanos , Protones , Tomografía Computarizada por Rayos X/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagen , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/radioterapia , Imagen por Resonancia Magnética/métodos , Radioterapia de Intensidad Modulada/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Dosificación Radioterapéutica , Procesamiento de Imagen Asistido por Computador/métodos
8.
Zhongguo Zhong Yao Za Zhi ; 47(12): 3185-3191, 2022 Jun.
Artículo en Zh | MEDLINE | ID: mdl-35851110

RESUMEN

Severe leaf spot on Polygonum cuspidatum was found in the planting base of P. cuspidatum in Fangxian county, Shiyan of Hubei province. To clarify the types of pathogens and their pathogenesis, the present study isolated and purified the pathogen of leaf spot disease of P. cuspidatum according to Koch's postulates, determined the pathogenicity of the pathogen, and investigated its biological characteristics. Meanwhile, the inhibitory effects of 11 types of fungicides on the bacteria were determined according to the mycelium growth rate, and suitable prevention and control drugs were selected. The results showed that the pathogen isolated from the diseased leaves of P. cuspidatum was Phoma rhei by morphological and molecular identification. The colony morphology and microscopic characteristics were the same as those of Ph. rhei. The homology of rDNA-ITS and TEF gene sequences with Ph. rhei reached 99.96% and 99.43%, respectively. The optimal growth temperature of Ph. rhei was 25 ℃, and the optimal pH was 7-10. Furthermore, Ph. rhei grew faster under dark or light conditions. In fungicides, 0.3% eugenol, 250 g·L~(-1) propiconazole, and 33.5% quinoline copper had significant inhibitory effects on the pathogen with EC_(50) values of 57.54, 59.58, 88.69 µg·mL~(-1), respectively. Eugenol is a botanical fungicide, which can be used as a green and environmentally friendly fungicide in the prevention and control of P. cuspidatum. This study reported for the first time that the pathogen of P. cuspidatum leaf spot was Ph. rhei. investigated the biological characteristics of the pathogen, and screened the indoor chemicals, which provided a theoretical basis for the prevention and control of P. cuspidatum leaf spot in production.


Asunto(s)
Fallopia japonica , Fungicidas Industriales , Ascomicetos , Eugenol , Fungicidas Industriales/farmacología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control
9.
Exp Eye Res ; 204: 108446, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33476605

RESUMEN

Neovascular age-related macular degeneration (neoAMD) is the leading cause of blindness in AMD and manifests as choroidal neovascularization (CNV). Anti-vascular endothelial growth factor (VEGF) therapies are the mainstay treatments but with limited efficacy and cause detrimental effects on the retina after long-term application. These disadvantages warrant alternative strategy. Herein, we examined the effect on CNV by intravitreal injection of bortezomib, a reversible proteasome inhibitor, and further dissected the mechanism. Krypton red Laser was used to create CNV model in mice. The angiogenesis volume was assessed in choroidal flat-mount with isolectin GS-IB4 labeling and the leakage was examined with fluorescein fundus angiography. Injection of Borsub inhibited angiogenesis in the CNV model which was dose-dependent; the injection significantly inhibited leakage as well. Furthermore, Borsub injection reduced the contents of VEGF-A, macrophage chemotactic factor 1 (MCP-1), and platelet-derived growth factor (PDGF)-D but not PDGF-B, examined by enzyme-linked immunosorbent assay, in choroid/retinal pigment epithelium (RPE) tissue. These injections also reduced phospho-VEGFR-2 and phospho-PDGFRß in choroid/RPE tissue examined by immunoblotting. Moreover, Borsub inhibited the recruitment of mural cells or macrophages to laser-injured spots. Injection of Borsub indicated negative effect on scotopic and photopic responses recorded by electroretinogram. Altogether, intravitreal injection of Borsub significantly reduced CNV by antagonizing VEGF-A/Flk-1 and PDGF-D/PDGFRß pathways without impacting electroretinography parameters. Thus, Borsub may offer an invaluable therapy for the prevention and treatment of neoAMD.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/uso terapéutico , Bortezomib/uso terapéutico , Neovascularización Coroidal/tratamiento farmacológico , Modelos Animales de Enfermedad , Linfocinas/antagonistas & inhibidores , Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Western Blotting , Quimiocina CCL2/antagonistas & inhibidores , Quimiocina CCL2/metabolismo , Neovascularización Coroidal/metabolismo , Neovascularización Coroidal/fisiopatología , Reposicionamiento de Medicamentos , Electrorretinografía/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Angiografía con Fluoresceína , Etiquetado Corte-Fin in Situ , Inyecciones Intravítreas , Linfocinas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Confocal , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Transducción de Señal/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo
10.
New Phytol ; 222(1): 275-285, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30471121

RESUMEN

In cereal crops, ABA deficiency during seed maturation phase causes pre-harvest sprouting (PHS), and molybdenum cofactor (MoCo) is required for ABA biosynthesis. Here, two rice PHS mutants F254 and F5-1 were characterized. In addition to the PHS, these mutants showed pleiotropic phenotypes such as twisting and slender leaves, and then died when the seedling developed to four or five leaves. Map-based cloning showed that OsCNX6 and OsCNX1 encoding homologs of MoaE and MoeA were responsible for F254 and F5-1 mutants, respectively. Genetic complementation indicated that OsCNX6 not only rescued the PHS and seedling lethal phenotype of the cnx6 mutant, but also recovered the MoCo-dependent enzyme activities such as xanthine dehydrogenase (XDH), aldehyde oxidase (AO), nitrate reductase (NR) and sulfite oxidase (SO). Expression pattern showed that OsCNX6 was richly expressed in seed during embryo maturation by quantitative reverse transcriptase PCR and RNA in situ hybridization. Furthermore, the OsCNX6 overexpression plants can significantly enhance the MoCo-dependent enzyme activities, and improved the osmotic and salt stress tolerance without unfavorable phenotypes. Collectively, these data indicated that OsCNX6 participated in MoCo biosynthesis, and is essential for rice development, especially for seed dormancy and germination, and OsCNX6 could be an effective target for improving abiotic stress tolerance in rice.


Asunto(s)
Vías Biosintéticas , Coenzimas/biosíntesis , Metaloproteínas/biosíntesis , Mutación/genética , Oryza/crecimiento & desarrollo , Oryza/genética , Adaptación Fisiológica , Regulación de la Expresión Génica de las Plantas , Cofactores de Molibdeno , Oryza/fisiología , Ósmosis , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pteridinas , Estrés Salino/genética , Estrés Fisiológico/genética
11.
Exp Eye Res ; 182: 93-100, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30917905

RESUMEN

Choroidal neovascularization (CNV) is a hallmark of exudative age-related macular degeneration (exAMD) and a major cause of visual loss in AMD. Despite the widespread use of anti-VEGF therapy, serious adverse effects arise from repeated intravitreal injection of anti-VEGF antibodies, which warrant alternative strategy. We report herein that in a CNV murine model created by krypton red laser, intravenous injection of a serine racemase inhibitor, l-Aspartic acid ß-hydroxamate (L-ABH), significantly reduced CNV at the dose 6 mg/kg on the first day before and followed by 3 mg/kg on the third day after laser injury. The CNV volumes were analyzed with isolectin GS-IB4 staining on choroidal/RPE flat mounts on the seventh day after laser injury. Injection of L-ABH did not produce negative effects on retinal function and visual behavior. To dissect the mechanism in vitro, pretreatment with L-ABH in primary RPE cultures significantly reduced production of vascular endothelial growth factor (VEGF) and macrophage chemotactic protein 1 (MCP-1) by TNFα-primed RPEs. Consistent with these observations, L-ABH pretreatment significantly attenuated macrophage migration mediated by TNFα-primed RPE. Collectively, intravenous injection of L-ABH significantly reduced CNV volumes via reducing production of VEGF and MCP-1 by inflammation-primed RPEs.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Asparagina/análogos & derivados , Neovascularización Coroidal/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Animales , Antineoplásicos/administración & dosificación , Asparagina/administración & dosificación , Células Cultivadas , Coroides/patología , Neovascularización Coroidal/metabolismo , Neovascularización Coroidal/patología , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Inflamación/metabolismo , Inflamación/patología , Inyecciones Intravenosas , Inyecciones Intravítreas , Ratones , Ratones Endogámicos C57BL , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Agudeza Visual
12.
Acta Oncol ; 58(2): 257-264, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30398090

RESUMEN

BACKGROUND: In this study, a deep convolutional neural network (CNN)-based automatic segmentation technique was applied to multiple organs at risk (OARs) depicted in computed tomography (CT) images of lung cancer patients, and the results were compared with those generated through atlas-based automatic segmentation. MATERIALS AND METHODS: An encoder-decoder U-Net neural network was produced. The trained deep CNN performed the automatic segmentation of CT images for 36 cases of lung cancer. The Dice similarity coefficient (DSC), the mean surface distance (MSD) and the 95% Hausdorff distance (95% HD) were calculated, with manual segmentation results used as the standard, and were compared with the results obtained through atlas-based segmentation. RESULTS: For the heart, lungs and liver, both the deep CNN-based and atlas-based techniques performed satisfactorily (average values: 0.87 < DSC < 0.95, 1.8 mm < MSD < 3.8 mm, 7.9 mm < 95% HD <11 mm). For the spinal cord and the oesophagus, the two methods had statistically significant differences. For the atlas-based technique, the average values were 0.54 < DSC < 0.71, 2.6 mm < MSD < 3.1 mm and 9.4 mm < 95% HD <12 mm. For the deep CNN-based technique, the average values were 0.71 < DSC < 0.79, 1.2 mm < MSD <2.2 mm and 4.0 mm < 95% HD < 7.9 mm. CONCLUSION: Our results showed that automatic segmentation based on a deep convolutional neural network enabled us to complete automatic segmentation tasks rapidly. Deep convolutional neural networks can be satisfactorily adapted to segment OARs during radiation treatment planning for lung cancer patients.


Asunto(s)
Atlas como Asunto , Neoplasias Pulmonares/radioterapia , Redes Neurales de la Computación , Órganos en Riesgo/diagnóstico por imagen , Reconocimiento de Normas Patrones Automatizadas/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Anatomía Artística , Esófago , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Neoplasias Pulmonares/patología , Órganos en Riesgo/patología , Radiografía Abdominal , Radiografía Torácica , Columna Vertebral , Carga Tumoral
13.
Zhongguo Zhong Yao Za Zhi ; 44(17): 3711-3717, 2019 Sep.
Artículo en Zh | MEDLINE | ID: mdl-31602943

RESUMEN

In this paper,the fingerprint of different varieties of chrysanthemum were established with " Similarity Evaluation System for Chromatographic Fingerprint of Chinese Materia Medica" and the content of chlorogenic acid,galuteolin and 3,5-O-dicaffeoylquinic acid in 29 batches of different varieties of chrysanthemum in Futianhe town,Huangtugang town and Wuhan city were compared. At the same time,similarity evaluation and common peak clustering analysis were carried out. There were 11 common peaks in the fingerprints of 29 batches of different varieties of chrysanthemum,and the similarity ranged from 0. 802 to 0. 975. Hangju and Gongju were divided into one group by cluster analysis,and Huangju into another category. The established fingerprint method provides a basis for the identification of chrysanthemum cultivars. The content of 29 batches of chlorogenic acid was between 4. 092 and 11. 723 mg·g-1,luteolin was between 1. 010 and 11. 713 mg·g-1,and 3,5-O-dicaffeoylquinic acid was between 8. 828 and 33. 435 mg·g-1,both reach the pharmacopoeia standard,but the effective components of different varieties of chrysanthemum were quite different. Based on the contents of three active ingredients and the diversity of fingerprint peaks,the quality of the characteristic germplasm resource of local Fubaijuin Macheng is superior,and the protection of local characteristic germplasm resource should be strengthened in production.


Asunto(s)
Chrysanthemum/química , Fitoquímicos/análisis , Ácido Clorogénico/análogos & derivados , Ácido Clorogénico/análisis , Cromatografía Líquida de Alta Presión , Luteolina/análisis
14.
Zhongguo Zhong Yao Za Zhi ; 44(7): 1381-1391, 2019 Apr.
Artículo en Zh | MEDLINE | ID: mdl-31090295

RESUMEN

To study the effects of fresh-cut drying methods on the appearance and internal components of Panax notoginseng, and explore the feasibility of fresh-cut drying methods of P. notoginseng, so as to provide more effective processing methods for the production of P. notoginseng slices and Chinese patent medicines. In this study, we have compared the effects of 6 different drying methods on drying time, drying rate, density, appearance and internal components of P. notoginseng roots. It takes about 453 h to dry by whole-root drying in the sun, with a long constant speed period and a slow drying rate, the time of whole-root drying at 50 ℃ was shortened by 61.6% compared with whole-root drying in the sun, which resulted in the decrease of density and poor appearance of the medicinal material with hollow and crack appeared in the xylem, while the drying time of fresh-cut drying method was reduced by 61.82% to 91.58% and the drying rate increased greatly, due to the relatively slow drying process in the sun or in the shade after fresh-cut, salting-out and whitening appeared on the surface, and the internal components were all decreased to some extent. The drying time of fresh-cut drying at 50 ℃ was 91.58% and 68.83% shorter than that of whole-root drying in the sun and at 50 ℃, respectively. When drying at 50 ℃ after fresh-cut, the appearance and content of internal components of the medicinal materials were better, the appearance was yellowish green, the cut sections were clear with uniform pore distribution, and the content of saponin components was increased by 7.24% compared with that of the whole-root drying at 50 ℃, When drying at 40 ℃, the surface of slices has salting-out and whitening spots, and the loss of dencichine and total sugar was large, but at 60 ℃, this high temperature made the rate of dehydration of slices was extremely fast, which led to severe cracking and fragmentation, and the loss of total sugar and alcohol extract was large. By vacuum freeze drying after fresh-cut, the structure of medicinal materials slices was loose, the density was greatly reduced, and the appearance was different from those recorded in traditional books. The contents of total saponin components and dencichine were increased by 16.51% and 22.54%, respectively, compared with traditional whole-root drying. The fresh-cut process method is feasible in the production of P. notoginseng slices. In production, it is recommended that drying at 50 ℃ after fresh-cut can make the medicinal materials better in appearance and content of internal components, which is convenient for the subsequent processing and industrial feeding extraction. For the purpose of internal contents, it is better to adopt freeze-drying after fresh-cut processing method.


Asunto(s)
Desecación , Medicamentos Herbarios Chinos/normas , Panax notoginseng , Saponinas/análisis , Liofilización , Raíces de Plantas , Control de Calidad
15.
J Neurochem ; 143(3): 375-388, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28892569

RESUMEN

Choroidal neovascularization (CNV) is a leading cause of blindness in age-related macular degeneration. Production of vascular endothelial growth factor (VEGF) and macrophage recruitment by retinal pigment epithelial cells (RPE) significantly contributes to the process of CNV in an experimental CNV model. Serine racemase (SR) is expressed in retinal neurons and glial cells, and its product, d-serine, is an endogenous co-agonist of N-methyl-d-aspartate receptor. Activation of the receptor results in production of nitric oxide (. NO), a molecule that promotes retinal and choroidal neovascularization. These observations suggest possible roles of SR in CNV. With laser-injured CNV mice, we found that inactivation of SR-coding gene (Srrnull ) significantly reduced CNV volume, neovascular density, and invading macrophages. We exploited the underlying mechanism in vivo and ex vivo. RPE from wild-type (WT) mice expressed SR. To explore the possible downstream target of SR inactivation, we showed that choroid/RPE homogenates extracted from laser-injured Srrnull mice contained less inducible nitric oxide synthase and decreased phospho-VEGFR2 compared to amounts in WT mice. In vitro, inflammation-primed WT RPEs expressed more inducible NOS, produced more. NO and VEGF than did inflammation-primed Srrnull RPEs. When co-cultured with inflammation-primed Srrnull RPE, significantly fewer RF/6A-a cell line of choroidal endothelial cell, migrated to the opposite side of the insert membrane than did cells co-cultured with pre-treated WT RPE. Altogether, SR deficiency reduces RPE response to laser-induced inflammatory stimuli, resulting in decreased production of a cascade of pro-angiogenic cytokines, including. NO and VEGF, and reduced macrophage recruitment, which contribute synergistically to attenuated angiogenesis.


Asunto(s)
Ceguera/patología , Neovascularización Coroidal/genética , Regulación de la Expresión Génica/genética , Óxido Nítrico/metabolismo , Racemasas y Epimerasas/deficiencia , Epitelio Pigmentado de la Retina/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Ceguera/etiología , Ceguera/genética , Células Cultivadas , Neovascularización Coroidal/patología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de la radiación , Rayos Láser/efectos adversos , Lipopolisacáridos/farmacología , Macrófagos/fisiología , Macrófagos/efectos de la radiación , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación/genética , ARN Mensajero/metabolismo , Racemasas y Epimerasas/genética , Epitelio Pigmentado de la Retina/efectos de los fármacos , Serina/metabolismo
16.
Zhong Yao Cai ; 39(4): 727-31, 2016 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30132310

RESUMEN

Objective: To study the taxonomy and distribution of Chinese medicinal centipedes. Methods: The species of Chinese medicinal centipedes were investigated in the light of their morphology. According to the feature of life, the distribution of centipedes were explored. Results: There were 12 centipede species in China, and seven of them were used for medical, the species could be effectively distinguished by the identification key. It was suggested that their characteristics were related to the climatic factors such as temperature, humidity, altitude and air pressure. Conclusion: The distribution of medicinal centipede is characteristics of "three river system distribution belts" and "three geographical distribution areas". The results provide the basis for the development and application of medicinal centipedes in China.


Asunto(s)
Artrópodos , Altitud , Animales , China , Humedad , Plantas Medicinales , Temperatura
17.
Biochem Biophys Res Commun ; 464(4): 1241-1247, 2015 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-26212440

RESUMEN

Kruppel-like factor 2 (KLF2) is a crucial anti-angiogenic factor. However, its precise role in hepatic angiogenesis induced by liver sinusoidal endothelial cells (LSECs) remain unclear. This study was aimed to evaluate the effect of KLF2 on angiogenesis of LSECs and to explore the corresponding mechanism. Cultured human LSECs were infected with different lentiviruses to overexpress or suppress KLF2 expression. The CCK-8 assay, transwell migration assay and tube formation test, were used to investigate the roles of KLF2 in the proliferation, migration and vessel tube formation of LSECs, respectively. The expression and phosphorylation of ERK1/2 were detected by western blot. We discovered that the up-regulation of KLF2 expression dramatically inhibited proliferation, migration and tube formation in treated LSECs. Correspondingly, down-regulation of KLF2 expression significantly promoted proliferation, migration and tube formation in treated LSECs. Additionally, KLF2 inhibited the phosphorylation of ERK1/2 pathway, followed by the function of KLF2 in the angiogenesis of LSECs disrupted. In conclusion, KLF2 suppressed the angiogenesis of LSECs through inhibition of cell proliferation, migration, and vessel tube formation. These functions of KLF2 may be mediated through the ERK1/2 signaling pathway.


Asunto(s)
Células Endoteliales/fisiología , Factores de Transcripción de Tipo Kruppel/metabolismo , Hígado/citología , Hígado/fisiología , Sistema de Señalización de MAP Quinasas/fisiología , Neovascularización Fisiológica/fisiología , Células Cultivadas , Humanos
18.
Water Sci Technol ; 71(7): 1106-12, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25860715

RESUMEN

The extracellular polymeric substances (EPS) are important macromolecular components in microbial aggregates. The three EPS extraction methods - ultrasound + cation exchange resins (CER) + sulfide, ultrasound + formamide + NaOH, and ultrasound + heat - were investigated in the study, and the component differences of extracted EPS from the loose flocs and dense aerobic granules were compared using chemical analysis and three-dimensional excitation-emission matrix (3D-EEM). Results showed that the contents of EPS were extracted effectively by ultrasound + formamide + NaOH and ultrasound + heat methods, and the ultrasound + CER + sulfide method did not extract the polysaccharides (PS) or protein (PN) contents from the sludge samples. The 3D-EEM analysis indicated that the nature of peak B/D, peak C/E/F, and peak A/G were attributed to PN-like, humic acid-like and fulvic acid-like fluorophores. All fluorophores can be detected from the EPS extracted through the ultrasound + heat method. Hopefully this will provide more information about the EPS interaction mechanism of microbial aggregates.


Asunto(s)
Polímeros/química , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Resinas de Intercambio de Catión/química , Formamidas/química , Calor , Hidróxido de Sodio/química , Sulfuros/química , Ultrasonido
19.
Rev Esp Enferm Dig ; 107(2): 63-71, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25659387

RESUMEN

BACKGROUND AND AIMS: Statins are reported to have a beneficial effect on portal hypertension (PTH); however, the exact mechanism remains unknown. Hepatic stellate cells (HSCs) can be activated by transforming growth factor beta (TGFâ) and play an important role in angiogenesis leading to PTH. Statins potently stimulate the transcription factor, Kruppel-like factor 2 (KLF2), which can negatively regulate angiogenesis. Our present study aimed to investigate the anti-angiogenic potential of statins in HSCs through the KLF2 pathway. METHOD: TGFâ-induced human HSCs were exposed to simvastatin. Cell viability and proliferation were determined by MTT and BrdU-proliferation assays, respectively. Cell migration was investigated using a transwell and wound-healing assays. Gene quantification was measured by real-time polymerase chain reaction. Protein expression was detected by western blot analysis and immunohistochemistry. Inflammatory factors were measured using enzyme-linked immunosorbent assays. RESULT: Simvastatin was found to reduced cell migration and proliferation and inhibit expression of alpha smooth muscle actin in TGFâ-induced HSCs. Furthermore, simvastatin promoted already increased mRNA and protein levels of KLF2 in TGFâ-induced HSCs. In accordance with KLF2 overexpression, simvastatin increased production of endothelial nitric oxide synthesis (eNOS) and downregulated expression of some proangiogenic proteins, such as vascular endothelial growth factor, hypoxia inducible factor-1a and nuclear factor-kappa B in TGFâ-induced HSCs. At the same time, secretion of interferon-gamma increased in TGFâ induced HSCs, which was decreased by simultaneous addition of simvastatin. CONCLUSION: Simvastatin suppressed the proangiogenic environment of HSCs activated by TGFâ, and KLF2 pathway is involved in the course.


Asunto(s)
Células Estrelladas Hepáticas/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Factores de Transcripción de Tipo Kruppel/metabolismo , Neovascularización Fisiológica/efectos de los fármacos , Simvastatina/farmacología , Biomarcadores/metabolismo , Línea Celular , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Humanos , Neovascularización Fisiológica/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa
20.
Zhongguo Zhong Yao Za Zhi ; 40(18): 3608-15, 2015 Sep.
Artículo en Zh | MEDLINE | ID: mdl-26983209

RESUMEN

The aim of this paper is to apply Raman spectroscopy technique to develop rapid quantitative models for five kinds of Traditional Chinese Medicine containing CaCO3. In the experiment, Raman spectras of 67 batch of sample including Otolithum Sciaenae, Galaxeae Os, Ophicalcitum, Calcite, Stalactite and their mixture which had different content of CaCO3 were collected, and the quantitative models were established by using an improved siPLS to optimize the characteristic spectral bands and using the CaCO3 contents which were measured by EDTA titration method as references. Compared with the results by EDTA titration, the established quantitative model for CaCO, content showed a prediction result that the average relative deviation of the prediction results is 2. 71% and the average recovery rate was 100.46%, when the content is between 0.465 4-0.999 7, and when the characteristic spectral bands of 1 290-1 280, 730-714, 700-690, 660-650, 465-460, 455-445, 405-385 cm(-1) had been optimized. The result also showed that the model using Raman spectroscopy and based on an improved siPLS can get a rapid determination for contents of 5 kinds of Traditional Chinese Medicine containing CaCO3.


Asunto(s)
Carbonato de Calcio/química , Medicamentos Herbarios Chinos/química , Plantas Medicinales/química , Espectrometría Raman/métodos , Análisis de los Mínimos Cuadrados , Modelos Estadísticos
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