Microparticles are small vesicles that are released by budding of the plasma membrane during cellular activation and apoptotic cell breakdown. A spectrum of cell types can release microparticles including endothelial cells, platelets, macrophages, lymphocytes and tumor cells. Biological effects of microparticles mainly include procoagulant activity, inhibition of inflammation and cancer progression. The present study shows that vitreous microparticles isolated from proliferative diabetic retinopathy (PDR) stimulated endothelial cell proliferation and increased new vessel formation, promoting the pathological neovascularization in PDR patients. Oxidative stress induces the formation of retina pigment epithelium-derived microparticles carrying membrane complement regulatory proteins, which is associated with drusen formation and age related macular degeneration. Microparticles from lymphocyte (LMP) play an important role in anti-angiogenesis by altering the gene expression pattern of angiogenesis-related factors in macrophages. Besides, LMP are important proapoptotic regulators for retinoblastoma cells through reduction of spleen tyrosine kinase expression and upregulation of the p53-p21 pathway which ultimately activates caspase-3. However, how to apply the microparticles in the prevention and treatment of retinal diseases is a major challenge, because the study of the microparticles in the fundus diseases is still limited. Further studies conducted would certainly enhance the application of microparticles in the fundus diseases.
Objective To observe the inhibitory characteristics of silver nanoparticles (AgNP) on bacterial biofilms and investigate their inhibitory effect on biofilm formation on three common orthopedic biomaterials. Methods The minimal inhibitory concentration (MIC) and minimal biofilm inhibitory concentration (MBIC) of AgNP were determined by microplate dilution assay. Biofilms of Staphylococcus aureus (ATCC 25923) were cultured on three orthopedic biomaterials (titanium alloy, titanium oxide, and stainless steel) and intervened with AgNP at concentrations of 32, 16, 8, 4, 2 and 0 μg/mL to determine the MBICs on the three materials. The effects of AgNP on biofilm formation were analyzed by scanning electron microscopy and measuring optical density. Results The MIC and MBIC of AgNP in the microplate assay were both 16 μg/mL. The MBICs of AgNP on biofilm formation in titanium oxide, titanium alloy, and stainless steel were 16 μg/mL, 32 μg/mL, and 32 μg/mL, respectively. Among the three materials, the lowest optical density was observed on titanium oxide, while the highest was on titanium alloy. Conclusions AgNP has strong antibacterial biofilm characteristics and can prevent the formation of Staphylococcus aureus biofilm in vitro. Biofilm formation is most pronounced on titanium alloy, least on titanium oxide, and intermediate on stainless steel.
Objective To assess the applied significance of carbon nanoparticles in central compartment lymph node dissection in treatment of cN0 papillary thyroid carcinoma. Methods Sixty-eight patients with cN0 papillary thyroid carcinoma who were treated in Tongji Hospital of Tongji Medical College from May. to Oct. in 2012 were randomly allocated to the control group （n=32） and the carbon nanoparticles trace group （tracer group， n=36）， receiving non-carbon nanoparticles trace and carbon nanoparticles trace respectively. All patients were received total resection of thyroid plus the affected side and （or） contralateral side central compartment lymph node dissection. The lymph node-related indexes（including number of dissected lymph node at Ⅵarea and lymph node metastasis rate at Ⅵarea） and operative indexs （including operation time， blood loss， drainage time， complication， and hospital stay） were collected and compared between the 2 groups. Results There were 205 and 324 dissected lymph node at central compartment in control group and tracer group respectively. The results of postoperative pathology showed that the number of lymph node in central compartment of the tracer group was much more than those of control group （8.99±2.24 vs. 6.41±1.56， P＜0.001）. The metastasis rate of central compartment lymph node were 40.6% （13/32） in control group and 47.2% （17/36） in tracer group， but there was no significant difference between the 2 groups （P=0.762）. But in medial area of laryngeal recurrent nerve， the metastasis rate in the tracer group （38.9%， 14/36） was much higher than those of control group （12.5%， 4/32）， P=0.029. There were no significant differences in the operation time， blood loss， drainage time， hospital stay， and complication incidence such as bleeding， temporary hypocalcemia， and injury of superior laryngeal nerve between 2 groups （P＞0.05）. All the patients in 2 groups had followed-up for 6 months without death， recurrence， and metastasis.Conclusions The lymphatic tracer technique of carbon nanoparticles may improve the number of dissected lymph nodes in central region of cN0 papillary thyroid carcinoma， without increasing （or prolonging） operation time， intraoperative blood loss， and postoperative hospital stay， and can accurately represent the metastasis of lymph node， thus to make the staging of the tumor accurately and guide postoperative treatment.
The present study was aimed at the optimal solution of the main muscular force distribution in the lower extremity during standing balance of human. The movement musculoskeletal system of lower extremity was simplified to a physical model with 3 joints and 9 muscles. Then on the basis of this model, an optimum mathematical model was built up to solve the problem of redundant muscle forces. Particle swarm optimization (PSO) algorithm is used to calculate the single objective and multi-objective problem respectively. The numerical results indicated that the multi-objective optimization could be more reasonable to obtain the distribution and variation of the 9 muscular forces. Finally, the coordination of each muscle group during maintaining standing balance under the passive movement was qualitatively analyzed using the simulation results obtained.
ObjectiveTo investigate the value of carbon nanoparticle adopted in reoperation for thyroid cancer recurrence.
MethodsFrom July to November of 2015, patients diagnosed with thyroid cancer recurrence in department of Thyroid & Parathyroid surgery, West China Hospital, Sichuan University were enrolled in the research. All enrollment patients underwent carbon nanoparticles location guided by ultrasonography before reoperation. Relative data about surgery and location were analyzed retrospectively.
ResultsTwenty-two patients were enrolled in the research. Mean operation time was (60.45±12.91) minutes. During surgery, a total of 405 (average 18.4) lymph nodes were harvested, and the staining rate was 71.9% (291/405). The pathological examination showed that there was a significant difference in the positive rate between carbon nanoparticles stained lymph nodes (45.0%, 131/291) and non-stained lymph nodes (5.3%, 6/114), P < 0.001. In addition, the positive rate in non-targeted stained lymph nodes was 30.2% (62/205). By contrast, it was 5.3% (6/114) in non-targeted non-stained lymph nodes. The difference showed significant significance (P < 0.001).
ConclusionsAdoption of carbon nanoparticles in reoperation for thyroid cancer, which improves efficiency of dissection for the non-palpable lymph nodes metastasis, is worth generalizing in clinical practice.
Objective To determine the best matching concentration of carbon nanoparticles suspension injection adsorb epirubicin by measuring the combination ratio of carbon nanoparticles suspension injection combined with epirubicin under different matching conditions. And then, to prove the adsorbability of carbon nanoparticles suspension injection adsorb epirubicin in vitro. Methods Firstly, epirubicin-carbon suspension of different concentrations will be prepared. The second, high performance liquid chromatography mass spectrometry（LC-MS） was used to assay the concentration of free epirubicin, and calculate the content of epirubicin that was combinated with carbon nanoparticles suspension injection. The difference of the ratio of carbon nanoparticles suspension injection combined with epirubicin under different matching conditions will be compared in the end. Results The combination ratio of carbon nanoparticles suspension injection combined with epirubicin solution of 5, 10, and 15 mg/ml were 85.6%, 85.7%, and 31.8%, respectively. Conclusions The adsorbability of carbon nanoparticles suspension injection adsorb epirubicin is favourable in vitro. Best matching concentration of carbon nanoparticles suspension injection adsorb epirubicin may be epirubicin solution of 5-10 mg/ml.
Feature extraction is a very crucial step in P300-based brain-computer interface (BCI) and independent component analysis (ICA) is a suitable P300 feature extraction method. But at present the convergence performance of the general ICA iteration methods are not very satisfactory. In this paper, a method based on quantum particle swarm optimizer (QPSO) algorithm and ICA technique is put forward for P300 extraction. In this method, quantum computing is used to impel ICA iteration to globally converge faster. It achieved the purpose of extracting P300 rapidly and efficiently. The method was tested on two public datasets of BCI Competition Ⅱ and Ⅲ, and a simple linear classifier was employed to classify the extracted P300 features. The recognition accuracy reached 94.4% with 15 times averaged. The results showed that the proposed method could extract P300 rapidly and the extraction effect did not reduce. It provides an experimental basis for further study of real-time BCI system.
【Abstract】ObjectiveTo construct eukaryotic expression vector pSecTag2/HygroB-CD59 of human CD59 and transfect NIH3T3 cells after encapsulated by chitosan. MethodsThe human CD59 fragments were obtained by PCR form CD59-pGEM-T Easy Vector, cloned into the eukaryotic expression vector pSecTag2/HygroB, identified by restriction endonuclease’s digestion and DNA sequencing. After the particles of pSecTag2/HygroB-CD59 were encapsulated by chitosan, the NIH3T3 cells were transfected by chitosanCD59 nanoparticles and detected CD59 expression by immunohistochemistry stain. ResultsThe CD59 fragment was 312 bp. Its sequence was as same as CD59 cDNA in Genbank. After having been transfected by chitosan-CD59 nanoparticles in 24 hours, the 3T3 cells showed diffusely positive in the cytoplasms by anti-CD59 immunohistochemistry. ConclusionThe eukaryotic expression vector of human CD59 is constructed and transfected to NIH3T3 cells after encapsulated by chitosan. It will be very helpful for further study on transgenic livers.
ObjectiveTo explore the application value of carbon nanoparticles during radical operation of differentiated thyroid cancer (DTC).MethodsThe DTC patients underwent total thyroidectomy plus neck lymph node (area Ⅳ) dissection from September 2017 to September 2019 in this hospital were retrospectively collected, who were divided into observation group and control group according to using carbon nanoparticles or not during the operation. The operation related informations [operation time, intraoperative blood loss, total drainage volume on day 3 after operation, postoperative hospitalization time, number of lymph nodes dissection (area Ⅳ), lymph node metastasis rate, and rate of parathyroid glands resected by mistake during operation] and blood calcium (Ca2+) level and parathyroid hormone (PTH) level before and after (24 h and 1 month) operation were compared between the two groups.ResultsA total of 134 patients with DTC were collected, including 76 patients in the observation group and 58 patients in the control group. There were no significant differences in baseline data such as gender, age, etc. between the two groups (P>0.05). Although there were no significant differences in terms of operation time, intraoperative blood loss, total drainage volume on day 3 after operation, postoperative hospitalization time, lymph node metastasis rate between the two groups (P>0.05), the numbers of lymph node dissection and metastasis (area Ⅳ) were more and rate of parathyroid glands resected by mistake during operation was lower in the observation group as compared with the control group (P<0.05). On hour 24 after operation, the levels of Ca2+ and PTH in the observation group were higher than those in the control group (P<0.05). On month 1 after operation, the PTH level in the observation group was still higher than that in the control group (P<0.05), but there was no significant difference in Ca2+ level between the two groups (P>0.05). ConclusionCarbon nanoparticles can better protect the function of parathyroid gland during radical operation of DTC and clean neck lymph nodes more thoroughly.
Cholangiocarcinoma is a highly malignant tumor. It is not sensitive to radiotherapy and chemotherapy and has a poor prognosis. At present, there is no effective treatment. As a new method for treating cancer, magnetic fluid hyperthermia has been clinically applied to a variety of cancers in recent years. This article introduces it to the cholangiocarcinoma model and systematically studies the effect of magnetic fluid hyperthermia on cholangiocarcinoma. Starting from the theory of magnetic fluid heating, the electromagnetic and heat transfer models were constructed in the finite element simulation software COMSOL using the Pennes biological heat transfer equation. The Helmholtz coil was used as an alternating magnetic field generating device. The relationship between the magnetic fluid-related properties and the heating power was analyzed according to Rosensweig’s theory. After the multiphysics coupling simulation was performed, the electromagnetic field and thermal field distribution in the hyperthermia region were obtained. The results showed that the magnetic field distribution in the treatment area was uniform, and the thermal field distribution met the requirements of hyperthermia. After the magnetic fluid injection, the cholangiocarcinoma tissue warmed up rapidly, and the temperature of tumor tissues could reach above 42 °C, but the surrounding healthy tissues did not heat up significantly. At the same time, it was verified that the large blood vessels around the bile duct, the overflow of the magnetic fluid, and the eddy current heat had little effect on thermotherapy. The results of this article can provide a reference for the clinical application of magnetic fluid hyperthermia for cholangiocarcinoma.
