ABSTRACT
Objective To investigate the transport and deposition behaviors of lowdensity lipoproteins (LDL) in the carotid artery and explore their associations with hemodynamic and morphological factors, so as to provide theoretical references for assessing the risk and predisposing regions of atherosclerosis based on the characteristics and associated factors of LDL deposition at the carotid artery wall. Methods Subject-specific computational models of the carotid artery based on medical images from six healthy volunteers were built, and the transport and wall deposition of LDL under pulsatile flow conditions were simulated, and finally the correlations of wall LDL concentration and total area of regions with LDL concentration polarization with flow velocity and morphological parameters of the carotid artery were quantitatively analyzed. Results Regions with significant LDL deposition often appeared in carotid sinus near distal end of the common carotid artery, with the degree and spatial distribution of deposition differing considerably among subjects. The degree of LDL deposition was determined mainly by flow velocity, i.e., the lower the flow velocity was, the higher the degree of LDL deposition and accordingly the larger the area of wall regions with LDL concentration polarization was; whereas the spatial distribution of LDL deposition was significantly affected by morphological characteristics (especially bifurcation eccentricity ratio) of the carotid artery, for example, the distribution patterns could be divided into two typical types (i.e., circular distribution, unilateral distribution) according to bifurcation eccentricity ratio. Conclusions Flow velocity and morphological characteristics of the carotid artery are major factors determining respectively the degree and spatial distribution of LDL deposition, and therefore subject-specifically measuring these parameters will provide useful information for screening individuals at high risk of atherosclerosis or identifying atheroprone regions.
ABSTRACT
In China,peritoneal metastasis of gastric cancer has main characteristics of high incidence,late staging and poor prognosis.However,the proposal of conversion therapy has brought hope to patients.Conversion therapy of peritoneal metastasis in gastric cancer is a novel concept,which aims at down-staging of the gastric cancer's primary lesion and effectively controlling the peritoneal metastases at the same time through valid chemotherapy and other means.Then the surgeons strive for performing radical gastrectomy and lymph node dissection (D2) to prolong survival time of the patients with advanced gastriccancer and improve their life quality.Systemic chemotherapy is the core of the methods of conversion therapy,while the local intraperitoneal chemotherapy can be used as a supplement.Neoadjuvant intraperitoneal-systemic chemotherapy (NIPS) is the most promising technique as conversion therapy due to the comprehensive advantages of the systemic chemotherapy and local intraperitoneal chemotherapy.In recent years,there were many clinical studies reporting NIPS for conversion therapy of peritoneal metastasis in gastric cancer.Therefore,this paper systematically reviews experiences of clinical application in order to provide references for clinical practice of conversion therapy in gastric cancer.