RESUMO
At present, feature-based 3D reconstruction and tracking technology is widely applied in the medical field. In minimally invasive surgery, the surgeon can achieve three-dimensional reconstruction through the images obtained by the endoscope in the human body, restore the three-dimensional scene of the area to be operated on, and track the motion of the soft tissue surface. This enables doctors to have a clearer understanding of the location depth of the surgical area, greatly reducing the negative impact of 2D image defects and ensuring smooth operation. In this study, firstly, the 3D coordinates of each feature point are calculated by using the parameters of the parallel binocular endoscope and the spatial geometric constraints. At the same time, the discrete feature points are divided into multiple triangles using the Delaunay triangulation method. Then, the 3D coordinates of feature points and the division results of each triangle are combined to complete the 3D surface reconstruction. Combined with the feature matching method based on convolutional neural network, feature tracking is realized by calculating the three-dimensional coordinate changes of the same feature point in different frames. Finally, experiments are carried out on the endoscope image to complete the 3D surface reconstruction and feature tracking.
Assuntos
Algoritmos , Imageamento Tridimensional , Endoscópios , Humanos , Redes Neurais de Computação , SiliconesRESUMO
Ovarian cancer is one of the most common gynecological types of cancer and is characterized by a relatively high incidence and high mortality rate. Evidence has demonstrated that paclitaxel (PTX) is an effective therapeutic treatment for human ovarian cancer. In the present study, the inhibitory effects of pegylated liposomal (PL)PTX on the growth of ovarian cancer cells were investigated in vitro; a CAOV3bearing mouse model was established to investigate the in vivo effects of PLPTX on ovarian tumor growth. In the present study, the underlying mechanism of tumor necrosis factor (TNF)induced inhibition of extracellular signalregulated kinase (ERK)/protein kinase B (AKT) signaling pathway mediated by PLPTX was analyzed within ovarian cancer cells. The results of the present study revealed that PLPTX significantly inhibited the growth and aggressiveness of ovarian cancer cells in vitro and in vivo and apoptotic ability increased upon administration of PLPTX. The expression levels of caspase3/9 were significantly upregulated within PLPTXtreated ovarian cancer cells. The expression and phosphorylation levels of ERK and AKT were markedly increased in response to PLPTX treatment. In addition, the inhibitory effects of PLPTX on ovarian cancer cells were eliminated by neutralizing antibodies against TNF. The observations of the present study revealed that PLPTX induced ovarian cell apoptosis via the TNFdependent pathway, which was significantly inhibited with the employment of antibodies against TNF. In vivo analysis demonstrated that PLPTX treatment significantly inhibited ovarian tumor growth and prolonged the survival of tumor bearing mice. In conclusion, the findings of the present study have provided an insight into the potential mechanism of PLPTXinduced apoptosis of ovarian cancer cells. As PLPTX has been reported to induce ovarian tumor cell apoptosis via the TNFinduced ERK/AKT signaling pathway, PLPTX may serve as an efficient anticancer drug for the treatment of ovarian cancer.