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1.
Eur J Radiol ; 143: 109891, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34481117

RESUMO

PURPOSE: The present study investigated the value of ultrasomics signatures in the preoperative prediction of the pathological grading of hepatocellular carcinoma (HCC) via machine learning. METHODS: A total of 193 patients were collected from three hospitals. The patients from two hospitals (n = 160) were randomly divided into training set (n = 128) and test set (n = 32) at a 8:2 ratio. The patients from a third hospital were used as an independent validation set (n = 33). The ultrasomics features were extracted from the tumor lesions on the ultrasound images. Support vector machine (SVM) was used to construct three preoperative pathological grading models for HCC on each dataset. The performance of the three models was evaluated by area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy. RESULTS: The ultrasomics signatures extracted from the grayscale ultrasound images could successfully differentiate between high- and low-grade HCC lesions on the training set, test set, and the independent validation set (p < 0.05). On the test set and the validation set, the combined model's performance was the highest, followed by the ultrasomics model and the clinical model successively (p < 0.05). Their AUC (along with 95 %CI) of these models was 0.874(0.709-0.964), 0.789(0.608-0.912), 0.720(0.534-0.863) and 0.849(0.682-0.949), 0.825(0.654-0.935), 0.770(0.591-0.898), respectively. CONCLUSION: Machine learning-based ultrasomics signatures could be used for noninvasive preoperative prediction of pathological grading of HCC. The combined model displayed a better predictive performance for pathological grading of HCC and had a stronger generalization ability.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Aprendizado de Máquina , Curva ROC , Estudos Retrospectivos , Ultrassonografia
2.
Int J Hyperthermia ; 37(1): 1260-1267, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33191810

RESUMO

AIM: The purpose of this study is to observe the volume change of prostate and laser-ablated lesions in the canine and to explore the mechanism and clinical significance through histopathology. MATERIALS AND METHODS: Transperineal laser ablation (TPLA) was performed under the guidance of transrectal ultrasound (TRUS) in eight canines. Two canines were sacrificed 1 day and 1 week after TPLA, respectively. The remaining six canines were sacrificed after finishing transrectal contrast-enhanced ultrasound (TR-CEUS) at three phases. RESULTS: The prostatic volumes immediately following TPLA and 1 week later were larger than before TPLA (20.1 ± 3.9 vs 17.1 ± 3.8 ml; 21.7 ± 3.6 vs 17.1 ± 3.8 ml, p < 0.05), but 1 month later, returned to the preoperative level (17.4 ± 3.2 ml). At three time points, the mean volumes of laser-ablated lesions at 3 W/600 J were 0.6 ± 0.2, 1.1 ± 0.4, and 1.7 ± 0.5 ml, respectively, while those of laser-ablated lesions at 3 W/1200 J were 1.2 ± 0.2, 1.6 ± 0.3, and 2.2 ± 0.5 ml, respectively. The mean volumes of laser-ablated lesions increased significantly over time after TPLA (p < 0.050). CONCLUSION: The prostate volume transient enlarges after TPLA, which prompts for clinical application that it should prolong appropriately the duration of urinary catheterization to avoid acute urinary retention. Many inflammatory cells were observed in the laser-ablated lesions and adjacent normal prostate parenchyma through histopathology. It is speculated that the inflammatory response is involved in the progression of tissue damage.


Assuntos
Terapia a Laser , Neoplasias da Próstata , Animais , Cães , Humanos , Lasers , Masculino , Próstata/diagnóstico por imagem , Próstata/cirurgia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Ultrassonografia
3.
PLoS One ; 15(4): e0223208, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32302311

RESUMO

The aim of this study was to investigate whether exogenous erythropoietin (EPO) administration attenuates N-methyl-D-aspartate (NMDA)-mediated excitotoxic retinal damage in Wistar rats. The survival rate of retinal ganglion cells (RGCs) were investigated by flat mount analysis and flow cytometry. A total of 125 male Wistar rats were randomly assigned to five groups: negative control, NMDA80 (i.e., 80 nmoles NMDA intravitreally injected), NMDA80 + 10ng EPO, NMDA80 + 50ng EPO, and NMDA80 + 250ng EPO. The NMDA80 + 50ng EPO treatment group was used to evaluate various administrated points (pre-/co-/post- administration of NMDA80). Meanwhile, the transferase dUTP Nick-End Labeling (TUNEL) assay of RGCs, the inner plexiform layer (IPL) thickness and the apoptotic signal transduction pathways of µ-calpain, Bax, and caspase 9 were assessed simultaneously using an immunohistochemical method (IHC). When EPO was co-administered with NMDA80, attenuated cell death occurred through the downregulation of the apoptotic indicators: µ-calpain was activated first (peak at ~18hrs), followed by Bax and caspase 9 (peak at ~40hrs). Furthermore, the images of retinal cross sections have clearly demonstrated that thickness of the inner plexiform layer (IPL) was significantly recovered at 40 hours after receiving intravitreal injection with NMDA80 and 50ng EPO. Exogenous EPO may protect RGCs and bipolar cell axon terminals in IPL by downregulating apoptotic factors to attenuate NMDA-mediated excitotoxic retinal damage.


Assuntos
Apoptose , Eritropoetina/farmacologia , N-Metilaspartato/farmacologia , Fármacos Neuroprotetores/farmacologia , Células Ganglionares da Retina/efeitos dos fármacos , Animais , Caspase 9/genética , Caspase 9/metabolismo , Regulação para Baixo , Masculino , Ratos , Ratos Wistar , Receptores de N-Metil-D-Aspartato/agonistas , Receptores de N-Metil-D-Aspartato/metabolismo , Células Ganglionares da Retina/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
4.
PLoS One ; 15(4): e0223229, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271751

RESUMO

To explore the shape characteristics of ablation lesions created via laser ablation (LA), radiofrequency ablation (RFA) and microwave ablation (MWA) in canine prostates and the clinical significance of these characteristics, six adult male beagles were randomly assigned to the LA, RFA, and MWA groups. These ablations were performed with common parameters applied in clinical practice (LA, 3 W/1200 J; RFA and MWA, 30 W/120 s). One ablation lesion was created in each lobe of the prostate via the ablation technique, resulting in a total of twelve ablation lesions. Transrectal ultrasound (TRUS) was used as guidance during puncture and to monitor changes in the ablation lesions. Finally, the ablation efficacy was assessed using transrectal contrast-enhanced ultrasonography (CEUS), and the transverse diameter (TRD), anteroposterior diameter (APD) and longitudinal diameter (LD) of each ablation lesion were measured. The volume (V) and the ratio (R) value were calculated. R reflects the shape characteristic of the ablation lesion (the R value close to 1.0 indicates a more spherical shape). The R values of the ablation lesions were 0.89 ± 0.02, 0.72 ± 0.01, and 0.65 ± 0.03 for RFA, MWA and LA, respectively, and they were significantly different (P = 0.027). The volumes of the ablation lesions were 2.17 ± 0.10 ml, 1.51 ± 0.20 ml, and 0.79 ± 0.07 ml for MWA, LA and RFA, respectively, and they were also significantly different (P = 0.001). The three abovementioned thermal ablation techniques with common parameters in clinical practice can be used for ablation in the prostate. The shapes and volumes of the ablation lesions of the three techniques were varied: The RFA-created lesions had the lowest volumes and were more spherical in shape, demonstrating that RFA could be used for the treatment of relatively small lesions or tumours adjacent to vital organs. The MWA lesions had the largest size with a spherical shape, which could be advantageous for the ablation of tumours with relatively large sizes. The sizes of the ablation lesions created via LA were between those of RFA and MWA but presented more oval in shape, suggesting that this method is highly appropriate for the ablation of benign prostatic hyperplasia (BPH).


Assuntos
Terapia a Laser , Complicações Pós-Operatórias , Hiperplasia Prostática , Ultrassom Focalizado Transretal de Alta Intensidade , Animais , Cães , Masculino , Terapia a Laser/efeitos adversos , Terapia a Laser/métodos , Terapia a Laser/veterinária , Micro-Ondas/uso terapêutico , Projetos Piloto , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/veterinária , Hiperplasia Prostática/cirurgia , Hiperplasia Prostática/veterinária , Ultrassom Focalizado Transretal de Alta Intensidade/efeitos adversos , Ultrassom Focalizado Transretal de Alta Intensidade/métodos , Ultrassom Focalizado Transretal de Alta Intensidade/veterinária
5.
PLoS One ; 8(1): e55291, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23383140

RESUMO

PURPOSE: This study aimed to evaluate the neuroprotective effect of EPO in the presence of N-methyl-d-aspartate (NMDA)-, trophic factor withdrawal (TFW)-, and tumor necrosis factor-alpha (TNF-α)-induced toxicity on total, small, and large retinal ganglion cells (RGCs). METHODS: Retinal cells from adult rats were cultured in a medium containing brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), basic fibroblast growth factor (bFGF), and forskolin. Expression of RGC markers and EPOR was examined using immunocytochemistry. RGCs were classified according to their morphological properties. Cytotoxicity was induced by NMDA, TFW, or TNF-α. RGC survival was assessed by counting thy-1 and neurofilament-l double-positive cells. RESULTS: EPO offered dose-dependent (EC50 = 5.7 ng/mL) protection against NMDA toxicity for small RGCs; protection was not significant for large RGCs. Time-course analysis showed that the presence of EPO either before or after NMDA exposure gave effective protection. For both small and large RGCs undergoing trophic factor withdrawal, EPO at concentrations of 1, 10, or 100 ng/mL improved survival. However, EPO had to be administered soon after the onset of injury to provide effective protection. For TNF-α-induced toxicity, survival of small RGCs was seen only for the highest examined concentration (100 ng/mL) of EPO, whereas large RGCs were protected at concentrations of 1, 10, or 100 ng/mL of EPO. Time-course analysis showed that pretreatment with EPO provided protection only for large RGCs; early post-treatment with EPO protected both small and large RGCs. Inhibitors of signal transduction and activators of transcription such as (STAT)-5, mitogen-activated protein kinases (MAPK)/extracellular-regulated kinase (ERK), and phosphatidyl inositol-3 kinase (PI3K)/Akt impaired the protective effect of EPO on RGCs exposed to different insults. CONCLUSION: EPO provided neuroprotection to cultured adult rat RGCs; however, the degree of protection varied with the type of toxic insult, RGC subtype, and timing of EPO treatment.


Assuntos
Eritropoetina/farmacologia , N-Metilaspartato/toxicidade , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/efeitos dos fármacos , Fator de Necrose Tumoral alfa/toxicidade , Análise de Variância , Animais , Fator Neurotrófico Derivado do Encéfalo , Contagem de Células , Técnicas de Cultura de Células , Fator Neurotrófico Ciliar , Colforsina , Meios de Cultura , Relação Dose-Resposta a Droga , Fator 2 de Crescimento de Fibroblastos , Imuno-Histoquímica , Microscopia de Fluorescência , Ratos , Testes de Toxicidade
6.
PLoS One ; 7(3): e33983, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22457807

RESUMO

PURPOSE: The aim of the study was to develop a high-content flow cytometric method for assessing the viability and damage of small, medium, and large retinal ganglion cells (RGCs) in N-methyl-D-aspartic acid (NMDA)-injury model. METHODS/RESULTS: Retinal toxicity was induced in rats by intravitreal injection of NMDA and RGCs were retrogradely labeled with Fluoro-Gold (FG). Seven days post-NMDA injection, flatmount and flow cytometric methods were used to evaluate RGCs. In addition, the RGC area diameter (D((a))) obtained from retinal flatmount imaging were plotted versus apparent volume diameter (D((v))) obtained from flow cytometry for the same cumulative cell number (sequentially from small to large RGCs) percentile (Q) to establish their relationship for accurately determining RGC sizes. Good correlation (r = 0.9718) was found between D((a)) and apparent D((v)). Both flatmount and flow cytometric analyses of RGCs showed that 40 mM NMDA significantly reduced the numbers of small and medium RGCs but not large RGCs. Additionally, flow cytometry showed that the geometric means of FG and thy-1 intensities in three types of RGCs decreased to 90.96±2.24% (P<0.05) and 91.78±1.89% (P>0.05) for small, 69.62±2.11% (P<0.01) and 69.07±2.98% (P<0.01) for medium, and 69.68±6.48% (P<0.05) and 69.91±6.23% (P<0.05) for large as compared with the normal RGCs. CONCLUSION: The established flow cytometric method provides high-content analysis for differential evaluation of RGC number and status and should be useful for the evaluation of various models of optic nerve injury and the effects of potential neuroprotective agents.


Assuntos
Citometria de Fluxo/métodos , Células Ganglionares da Retina/efeitos dos fármacos , Animais , Sobrevivência Celular , N-Metilaspartato/administração & dosagem , N-Metilaspartato/farmacologia , Ratos , Células Ganglionares da Retina/citologia , Corpo Vítreo
7.
Expert Opin Drug Deliv ; 5(12): 1313-21, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19040394

RESUMO

Erythropoietin (EPO), a glycoprotein, plays an important role in erythropoiesis and neuroprotection. EPO therapies for anemia or neurodegenerative diseases require frequent injections or high-dose systemic administration which may cause unwanted side effects. Various strategies for EPO delivery have been investigated for increasing EPO bioavailability and decreasing side effects, including nano/micro particles, PEGylation of EPO and transport-mediated delivery systems. Nano/micro particles provide EPO with long-term effect and protect EPO against proteolytic cleavage. PEGylated EPO prolong circulating time and reduce injection frequency of anemia treatment. A transport-mediated delivery system enables protein to cross biological barriers. Presently, there is no report about an effective delivery system of EPO for neuroprotection. This review focuses on EPO delivery systems for erythropoiesis or neuroprotection with prolonged duration and enhanced bioavailability.


Assuntos
Sistemas de Liberação de Medicamentos , Eritropoetina/administração & dosagem , Hematínicos/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Anemia/tratamento farmacológico , Animais , Preparações de Ação Retardada , Composição de Medicamentos , Eritropoese/efeitos dos fármacos , Eritropoetina/farmacologia , Eritropoetina/uso terapêutico , Hematínicos/farmacologia , Hematínicos/uso terapêutico , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Proteínas Recombinantes
8.
J Microencapsul ; 24(1): 82-93, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17438944

RESUMO

PURPOSE: Protein microencapsulation in biodegradable polymers is a promising route to provide for sustained release. The erythropoietin (EPO) microparticles are using human serum albumin (HSA) and poly-L-lysine (PK) as the protection complex to increased EPO integrity, entrapped efficiency and active EPO release by w/o/w solvent evaporation techniques. The optimum formulation development process was also reported by using FITC-OVA as a model protein. METHODS: The model protein FITC-ovalbumin and EPO are protected by human serum albumin and poly-L-lysine complex and encapsulated in 50:50 poly(DL-lactide-co-glycolide) by a w/o/w solvent evaporation method. Protein active integrity and degradation compound is measured by size-exclusion chromatography. Protein-loaded microparticle physical properties and in vitro active and degradation compounds release profile are characterized. RESULTS: High active integrity protein loading efficiency and particle yield of EPO or OVA-HSA/PK-loaded PLG microparticles are successfully produced by a w/o/w solvent evaporation method. Varied protection protein complex formulations and encapsulation processes are investigated. The high OVA model protein loading efficiency (80.2%), FITC-OVA content (0.24 microg mg(-1)) and yield (72.4%) are obtained by adding 100 microg mL(-1) FITC-OVA complex with 10% HSA/0.05% PK (Mw 1.5-3 kD) in the initial solution to protect the model protein. In vitro release profiles show more active OVA release from HSA/PK OVA-loaded than OVA-loaded only microparticles and also the amount of degraded protein that comes out after 3 weeks incubated in the PBS medium for OVA-loaded only microparticles is observed. The same formulation and preparation process resulted in EPO loading efficiency (68.4%), EPO content (0.23 microg mg(-1)) and yield (76.1%) for HSA/PK EPO-loaded microparticles. In vitro release profiles show active EPO sustained release over 7 days. Using HSA/PK as carried in the primary emulsion of EPO-loaded microparticles resulted in less burst release% than EPO-loaded only microparticles.


Assuntos
Preparações de Ação Retardada/isolamento & purificação , Composição de Medicamentos/métodos , Eritropoetina/administração & dosagem , Cápsulas , Fenômenos Químicos , Físico-Química , Fluoresceína-5-Isotiocianato/administração & dosagem , Humanos , Ovalbumina/administração & dosagem , Polilisina , Proteínas Recombinantes , Albumina Sérica
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