RESUMO
In the forensic estimation of bone age, the pelvis is important for identifying the bone age of teenagers. However, studies on this topic remain insufficient as a result of lower accuracy due to the overlapping of pelvic organs in X-ray images. Segmentation networks have been used to automate the location of key pelvic areas and minimize restrictions like doubling images of pelvic organs to increase the accuracy of estimation. This study conducted a retrospective analysis of 2164 pelvis X-ray images of Chinese Han teenagers ranging from 11 to 21 years old. Key areas of the pelvis were detected with a U-Net segmentation network, and the findings were combined with the original X-ray image for regional augmentation. Bone age estimation was conducted with the enhanced and not enhanced pelvis X-ray images by separately using three convolutional neural networks (CNNs). The root mean square errors (RMSE) of the Inception-V3, Inception-ResNet-V2, and VGG19 convolutional neural networks were 0.93 years, 1.12 years, and 1.14 years, respectively, and the mean absolute errors (MAE) of these networks were 0.67 years, 0.77 years, and 0.88 years, respectively. For comparison, a network without segmentation was employed to conduct the estimation, and it was found that the RMSE of the three CNNs above became 1.22 years, 1.25 years, and 1.63 years, respectively, and the MAE became 0.93 years, 0.96 years, and 1.23 years. Bland-Altman plots and attention maps were also generated to provide a visual comparison. The proposed segmentation network can be used to reduce the influence of restrictions like image overlapping of organs and can thus increase the accuracy of pelvic bone age estimation.
Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Adolescente , Adulto , Criança , Humanos , Processamento de Imagem Assistida por Computador/métodos , Pelve , Estudos Retrospectivos , Raios X , Adulto JovemRESUMO
Serum- and glucocorticoid-inducible kinase 3 (SGK3) is a downstream mediator of PI3K, which is essential for maintaining the functional integrity of podocytes. However, little is known about the role of SGK3 in podocyte function. Herein, we demonstrated that SGK3 contributes to the maintenance of podocyte integrity. Conditionally immortalized mouse podocyte cells (MPCs) were treated with puromycin aminonucleoside (PAN). PAN treatment inhibited the activity of SGK3 and the expression of podocin. Short hairpin RNA (shRNA)-mediated knockdown of SGK3 also reduced podocin expression in the absence of PAN. Adriamycin (ADR)-treated mice developed proteinuria and had decreased renal glomerular SGK3 expression in comparison to control mice. Consistent with a role for SGK3 in the ADR effect, SGK3 knockout (KO) mice had markedly reduced kidney podocin expression and significantly elevated proteinuria compared with wild-type mice. Electron microscopy revealed that SGK3 KO mice displayed partial effacement of podocyte foot processes. Further, a SGK3 target protein, glycogen synthase kinase-3 (GSK3), was discovered to be dramatically activated in PAN and SGK3 shRNA-treated MPCs and in SGK3 KO mice. Taken together, these data strongly suggest that SGK3 plays a significant role in regulating podocyte function, likely by controlling the expression and activity of GSK3.-Peng, L.-Q., Zhao, H., Liu, S., Yuan, Y.-P., Yuan, C.-Y., Mwamunyi, M.-J., Pearce, D., Yao, L.-J. Lack of serum- and glucocorticoid-inducible kinase 3 leads to podocyte dysfunction.
Assuntos
Podócitos/enzimologia , Proteínas Serina-Treonina Quinases/deficiência , Animais , Linhagem Celular Transformada , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Podócitos/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Puromicina Aminonucleosídeo/efeitos adversos , Puromicina Aminonucleosídeo/farmacologiaRESUMO
Quercetin, the primary dietary flavonol, exerts a strong inhibitory effect on calcineurin (CN), a unique Ca(2+)/calmodulin-dependent serine/threonine protein phosphatase. Using fluorescence spectroscopy (FS) we showed quercetin strongly bound to calcineurin catalytic subunit (CNA) with a ratio of 1:1; we also showed that calcineurin regulatory subunit (CNB) weakened this binding. In addition, the secondary structure of CNA was much tighter in the presence of quercetin. An FS study with CNA truncated mutant CNAa showed that the binding area for quercetin was reduced to the catalytic domain of CNA. Furthermore, fluorescence resonance energy transfer (FRET) results and molecular docking indicated three potential binding sites for quercetin, which were located at a region between the active centre of CNA and the CNB binding domain, a similar binding area to that of cyclosporin A and tacrolimus. Interestingly, this region was also important for CN substrate recognition.
RESUMO
Podocyte damage is commonly accompanied by destabilization of the podocalyxin (PC)/ezrin complex. Serum- and glucocorticoid-inducible kinase 3 (SGK3) plays a role in the maintenance of podocyte function, but the details of this role are poorly understood. Herein we demonstrated that SGK3 and its downstream target protein neural precursor cell expressed developmentally downregulated protein 4 subtype 2 (Nedd4-2) triggered PC and ezrin interaction. In adriamycin (ADR)-induced nephritic mice, and after puromycin aminonucleoside (PAN)-induced podocyte damage in vitro, PC and ezrin protein expression levels decreased significantly, while Nedd4-2 activity increased. Moreover, PAN treatment increased PC and ezrin ubiquitination and decreased PC/ezrin interaction in cultured mouse podocytes. The downregulation of SGK3 activity in mouse podocytes resulted in decreased PC and ezrin protein expression and increased the ubiquitin-proteasome degradation of PC and ezrin. Furthermore, upregulation of SGK3 activity mostly reversed the PAN-induced decrease in PC and ezrin protein expression. Overexpression of Nedd4-2 led to decreased ezrin protein expression via the upregulation of ezrin ubiquitination. In contrast, Nedd4-2 knockdown resulted in increased ezrin protein expression but decreased ezrin ubiquitination. In PC-transfected human embryonic kidney (HEK293T) cells, SGK3 activity downregulation and Nedd4-2 overexpression resulted in decreased PC/ezrin interaction. These results suggested that SGK3 triggers the ubiquitin-proteasome degradation of PC and ezrin, while the SGK3/Nedd4-2 signaling pathway regulates ezrin, but not PC, ubiquitination. Thus SGK3 helps to regulate podocyte function by maintaining the stability of the PC/ezrin complex.
Assuntos
Proteínas do Citoesqueleto/genética , Nefrite/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/genética , Sialoglicoproteínas/genética , Animais , Linhagem Celular Transformada , Proteínas do Citoesqueleto/metabolismo , Doxorrubicina/toxicidade , Humanos , Masculino , Camundongos , Ubiquitina-Proteína Ligases Nedd4/genética , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Nefrite/induzido quimicamente , Nefrite/genética , Nefrite/patologia , Podócitos/efeitos dos fármacos , Podócitos/metabolismo , Podócitos/patologia , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Estabilidade Proteica , Proteólise , Sialoglicoproteínas/metabolismo , Transdução de Sinais , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitinação/efeitos dos fármacosRESUMO
Objective To observe the effect of kangnao liquid on the expressions of LC3 and Beclin 1 in hippocampus after cerebral ischemia-reperfusion in rats, and to discuss the mechanism. Methods A total of 48 male SD rats were randomly divided into four groups:sham-operation group, model group, kangnao liqiud group [14.30 g/(kg·d)] and edaravone group [10.00 mg/(kg·d)], 12 rats in each group. The rats in kangnao liqiud group and edaravone group were administrated by intragastric administration. The rats in sham-operation group and model group were administrated with equal volume of normal saline. After treating for 7 days, except for the sham-operation group, the middle cerebral artery occlusion (MCAO) model was made by suture method in the other three groups. After 2 h of ischemia, the rats were reperfused for 24 h. Six rats in each group were randomly selected for observing the neurological function. TTC staining was used to observe the morphology of the brain tissue and calculate the percentage of infarction. The morphology of the cerebral cortex and hippocampus was observed by HE staining in the remaining animals, and the expressions of LC3 and Beclin 1 in the hippocampus were detected by immunohistochemical staining. Results Compared with the sham-operation group, model group showed an obvious neurological deficit, and the percentage of cerebral infarction increased significantly. At the same time, nerve cells of cerebral cortex and hippocampus revealed degeneration and necrosis, stroma edema, and the expressions of LC3 and Beclin 1 in hippocampus significantly increased (P<0.05). Compared with the model group, the neurological deficit symptoms and the percentage of cerebral infarction significantly reduced, changes of neuron morphology were lighter, and the expressions of LC3 and Beclin 1 decreased significantly in kangnao liqiud group and edaravone group (P<0.05).Conclusion Kangnao liquid shows protective effects on cerebral ischemia-reperfusion, which may be related with the decreased expressions of LC3 and Beclin 1 in hippocampus after cerebral ischemia-reperfusion in rats.