1.Determination of Trace Level Microcystins in Water Using Solid-phase Extraction and High Performance Liquid Chromatography
Chinese Journal of Analytical Chemistry 2001;29(5):522-525
This paper presents a method for trace level analysis of microcystins in water using solid-phase extraction and high performance liquid chromatography.The optimized condition enabled the determination of common microcystins at levels as low as 0.02~0.05μg/L,and the liner range is from 0.1μg/L to 50 μg/L. The method has been applied to the analysis of field sample from Dianchi lake.
2. Fabrication and evaluation of biomimetic biodegradable tissue-engineered annulus fibrosus scaffold
Chinese Journal of Tissue Engineering Research 2020;24(4):524-531
BACKGROUND: It is still difficult to construct tissue-engineered anulus fibrosus scaffolds which have bionic structure, suitable biodegradability and good biocompatibility. OBJECTIVE: To fabricate bionic biodegradable scaffolds with polycaprolactone (PCL) and polydioxanone (PDS) and evaluate the feasibility as a tissue-engineered annulus fibrosus scaffold. METHODS: Five groups of scaffolds at different PCL/PDS proportions were prepared by melt spinning technique: PCL, PCL/PDS70/30, PCL/PDS50/50, PCL/PDS30/70, and PDS groups. Scanning electron microscopy was used to observe the structure and measure the fiber diameter and pore size of these prepared scaffolds. The mechanical properties and contact angle of the scaffolds were measured. The in vitro and in vivo biodegradation of the scaffolds were observation by in vitro simulation and subcutaneous implantation. The expression of inflammatory factors interleukin-1β and tumor necrosis factor-α in the biodegraded tissues was detected. Human Wharton’s jelly mesenchymal stem cells were cultured for 7 days. Cell viability and proliferation was determined by live/dead cell staining. This study was approved by the Medical Ethics Committee of Tianjin Hospital, China on March 2, 2016. RESULTS AND CONCLUSION: Scanning electron microscopy results showed that the thickness of the scaffold fibers was uniform and the angle between fibers was 60°. The mechanical properties analysis showed that the tensile and compressive modulus of the PDS group was the lowest, which did not meet the mechanical requirements of the anulus fibrosus; the tensile and compressive modulus in the PCL group was the highest, and those in the PCL/PDS70/30 and PCL/PDS50/50 group were moderate. Hydrophilicity test showed that higher PDS proportion led to better hydrophilicity. Biodegradation test showed that the biodegradation of pure PDS and PCL/PDS30/70 was too fast, that of PCL was too slow, and that of PCL/PDS70/30 and PCL/PDS50/50 was appropriate. Analysis of inflammatory response around the biodegraded tissue showed that higher proportion of PCL in the scaffold resulted in more severe inflammatory response. CCK-8 and live/dead cell staining showed that human Wharton’s jelly mesenchymal stem cells had good proliferative activity and high survival rate in the PCL/PDS70/30, PCL/PDS50/50, and PCL/PDS30/70 groups. These results suggest that scaffolds in the PCL/PDS70/30 and PCL/PDS50/50 groups can simulate the structure of natural annulus fibrosus, have appropriate biodegradability, excellent mechanical properties and good biocompatibility, which make it a suitable candidate for tissue-engineered annulus fibrosus scaffold.
3.Computed tomography-guided 125I seed implantation combined with chemotherapy in treating recurrent ovarian cancer
Ying WANG ; Zhi GUO ; Weihao ZHANG ; Hong NI
Chinese Journal of Clinical Oncology 2015;(2):87-90
Objective:To evaluate the safety and efficacy of a palliative regimen of computed tomography (CT)-guided 125I seed im-plantation combined with chemotherapy for recurrent ovarian cancer. Methods:A total of 21 patients with recurrent ovarian cancer, who received 125I seed implantation and chemotherapy, were retrospectively analyzed. Out of the 29 lesions detected, 25 lesions were suitable for 125I seed implantation. Treatment planning system (TPS) was implemented preoperatively to determine the number and dis-tribution of 125I seeds. Under CT guidance, 125I seeds were implanted into the recurrent lesions using the TPS. Within 3 d of 125I seed im-plantation, liposomal paclitaxel was administered by intravenous infusion on day 1 and carboplatin by infusion via the feeding artery of tumor on day 2. Chemotherapy was repeated on a 21-day schedule. Efficacy and complications were evaluated during follow-up. Re-sults:After two cycles of chemotherapy, out of the 25 recurrent lesions that underwent 125I seed implantation, four lesions showed com-plete remission, 14 with partial remission, three with stable disease, and four with progression of disease. The objective response rate was 72%, and the pain relief rate was 82.4%. Karnofsky's performance status scores increased dramatically (P=0.019). The median pro-gression-free survival time was 6.8 months, median overall survival time was 14.2 months, and the 1-year survival rate was 42.9%. He-matologic toxicity and gastrointestinal reactions were the primary adverse conditions. No severe radiation complications and treat-ment-related deaths were observed in all patients. Conclusion:CT-guided 125I seed implantation combined with chemotherapy is active and well-tolerated in patients with recurrent ovarian cancer. This combined treatment cannot only significantly enhance the objective re-sponse rate, but also leads to remarkable improvement in cancer-related symptoms.
4.Expressions and clinical significance of HIF-1? and multidrug resistance genes in human colorectal adenocarcinoma
Weihao ZHANG ; Zhengjun QIU ; Zhiqian HU ; Jing SUN
China Oncology 2006;0(11):-
Background and purpose:Micro-environmental hypoxia is a common phenomenon in most human solid tumors,and this investigation is done to observe the expression of HIF-1? and chemo-resistance-associated genes in human colon cancer cell line under hypoxic micro-environment in vitro,and study the influence of micro-environmental hypoxia on chemo-resistance and the possible mechanisms in human colon cancer.Methods:Human colon cancer cell line SW620 was cultured under hypoxia for 12,24,48 hr,with normoxia as control.Then the expression of HIF-1? and chemo-resistance-associated genes mdr1/P-Gp、LRP were investigated by RT-PCR and western-blot.Results:With prolongation of the hypoxic time,the mRNA expressions of HIF-1? and LRP remained at the same level,but the mRNA expressions of mdr1 showed a time-dependent increase(P
5.Polymorphism analysis of exons 2 and 5 of PITX2 gene of neonatal intestinal malrotation
Jinyong PAN ; Huirong ZHANG ; Weihao DUAN ; Xiaoyan CAO
Chinese Journal of Applied Clinical Pediatrics 2016;(2):124-126
Objective To screen the neonatal malrotation with PITX2 gene exon 2 and 5 gene mutation through the study on molecular genetics.Methods From January 201 2 to December 201 4,1 5 cases of neonatal malro-tation infants(experimental group)and 25 healthy newborn infants(healthy control group)were selected as the research subjects from the First Affiliated Hospital of Shihezi University Medical College.The experimental group included 1 5 ca-ses of volvulus,4 cases of volvulus with duodenal atresia and 3 cases of volvulus with jejunal atresia.The clinical fea-tures were recorded and 3 mL peripheral venous blood from each subject was collected.After ethylenediamine tetraacetic acid (EDTA)anticoagulation,genomic DNA was extracted.Polymerase chain reaction (PCR)was used to amplify the exon 2 and exon 5 of PITX2 gene,and the direct sequencing method was used to screen whether there were mutations in these 2 loci.Results According to the findings of the matching gene,PITX2 gene exon 2 and exon 5 mutations were not detected in 15 cases with intestinal malrotation of the experimental group and 25 healthy newborns in the healthy control group.Conclusions Polymorphisms is not detected in PITX2 gene exon 2 and exon 5 in small groups of newborn,but this does not exclude the possibility the gene caused newborns suffering from intestinal malrotation by other means.
6.Expression of plexinA1 and Ki-67 in tissue of patients with human glioma cells and their clinical significance
Weijun WANG ; Hua YANG ; Feng LIU ; Xin XIANG ; Weihao ZHANG
Cancer Research and Clinic 2015;27(5):336-338
Objective To explore expression of plexinA1 and Ki-67 in tissue of human brain glioma cells and their clinical significance.Methods 43 specimens from patients with brain glioma were collected.Immunohistochemical (IHC) staining was used for detecting the expression of tissue plexinA1 and Ki-67 in human glioma cells of 43 cases of patients with brain glioma.The positive expression rate of plexinA1 and Ki-67 among the different pathological grade tissues and their clinical significance were analyzed.So did correlation studies about plexinA1 and Ki-67.Results The positive expression rates of plexinA1 in Ⅰ-Ⅱ grade group (18 cases) and Ⅲ-Ⅳ grade group (25 cases) were 22.22 % (4/18) and 72.00 % (18/25) (P < 0.05).The positive expression rates of Ki-67 in Ⅰ-Ⅱ grade group and Ⅲ-Ⅳ grade group were 16.67 % (3/18) and 56.00 % (14/25),respectively (P < 0.05).PlxinA1 and Ki-67 expression in the tissue of human brain glioma were positively correlated (r =0.997,P < 0.05).Conclusions The positive expression rate of plexinA1 is higher in high malignancy human glioma group than that in low malignancy group which has an important reference value in the estimation of prognosis for human glioma.PlexinA1 and Ki-67 maybe synergism in occurrence and development of glioma.
7.The relationship between the remnant tumor and the epithelial-mesenchymal transition after cryoablation:an experimental study
Xu CHANG ; Zhi GUO ; Tongguo SI ; Weihao ZHANG ; Haipeng YU ; Xueling YANG ; Hongcai YANG
Journal of Interventional Radiology 2017;26(8):722-726
Objective To investigate the effect of incomplete cryoablation on the biological behavior of prostatic cancer RM-1 cells and its mechanism.Methods RM-1 cells of prostatic cancer were placed in -20℃ icebox to be frozen for 5 min.After the recovery of the cell state,the RM-1 cells were frozen again for 10 min and 15 min successively.After culture for one day,the cellular morphology was microscopically examined.A total of 20 C57/BL mice were used to establish the tumor-bearing models,which were randomly and equally divided into the control group and the incomplete cryoablation group with 10 mice in each group.At scheduled time points the tumor lesion size was measured for all mice.The mice were sacrificed at 14 days,the lung tissues were collected and were stained with lE;the numbers of metastatic lesions in the lung were calculated.Transwell assay was used to test the cell migration and invasion,immuno-blotting method was adopted to determine the epithelial-mesenchymal transition-related (EMT-related) protein expression level,and the enzyme-linked immunosorbent assay (ELISA) was employed to check the secretion volume of transforming growth factor-beta (TGF-β).Results After incomplete cryoablation,RM-1 cells became disorderly arranged,their morphology was changed,and antenna structure might be formed.At 3 and 7 days after cryoablation,the tumor size in the incomplete cryoablation group was slightly smaller than that in the control group,but only the difference at 7 days after cryoablation was statistically significant between the two groups (P=0.019).At 10 and 14 days after cryoablation,the tumor volume of the two groups was almost equal.The pulmonary metastatic lesions in the incomplete cryoablation group were obviously much more than those in the control group (P<0.001).Transwell assay indicated that the cell migration and invasion ability in the incomplete cryoablation group was stronger than that in the control group (P<0.05).Immuno-blotting test revealed that,when compared with the control group,in the incomplete cryoablation group the expressions of N-cadherin,MMP-9 and Vimentin were up-regulated,while the expression of E-cadherin was downregulated.ELISA test showed that increased secretion of TGF-β was observed in the incomplete cryoablation group.Conclusion Incomplete cryoablation can enhance the migration and invasion ability of RM-1 cells,increase the number of pulmonary metastatic lesions in tumor-bearing mice,and affect the EMT-related protein expression level.
8.Clinical characteristics in patients with allergic rhinitis and nonallergic rhinitis in Guangzhou
Weihao WANG ; Xuekun HUANG ; Zhuanggui CHEN ; Huiyi DENG ; Yulian CHEN ; Gehua ZHANG ; Qintai YANG
Chinese Archives of Otolaryngology-Head and Neck Surgery 2016;23(9):533-536
OBJECTIVE To obtain and compare the clinical characteristics in patients with allergic rhinitis(AR) and nonallergic rhinitis(NAR) and investigate the trends in the proportion of AR and NAR in recent 10 years in Guangzhou. METHODS 5486 patients with nasal hyper-reactivity symptoms were divided into the AR group and NAR group. Clinical data including gender, age distribution and seasonality were analyzed. RESULTS The trends in the proportion of AR and NAR during the past decade did not change significantly. Male made up the majority of AR patients and NAR patients and AR patients were significantly younger than NAR patients. Male AR patients were significantly younger than females, while there were no significant difference in the age distribution among the male NAR patients and female ones. As the age increasing, the proportion of AR and NAR patients in overall study population present opposite tendency. The main onset season in AR was summer and in NAR was winter in Guangzhou city. CONCLUSION There were significant differences between AR and NAR in age, gender and seasonality. However, the trends in the proportion of AR and NAR in recent 10 years did not change significantly in Guangzhou.
9.Distribution and treatment onintractable epistaxis in concealed sites
Qintai YANG ; Huiyi DENG ; Weihao WANG ; Xuekun HUANG ; Lei LV ; Xian LIU ; Gehua ZHANG
Chinese Archives of Otolaryngology-Head and Neck Surgery 2016;23(10):602-605
OBJECTIVE To drew the map of distribution of concealed sites in epistaxis and optimize the mode of diagnosis and treatment. METHODS We have searched 117 references on intractable/refractory/latent epistaxis treated under nasal endoscopy in the last decade, including 11 708 cases with epistaxis. There were total 11 860 cases in this study plus 152 cases in our hospital. We summed up the experiences of the optimized treatment mode performed on concealed epistaxis, which was searching the accurate bleeding areas by nasal endoscopy and performing minimally invasive radiofrequency treatment without nasal packing. RESULTS We had found that the offending arteries about epistaxis are mainly sphenopalatine artery and anterior or posterior ethmoid artery. The frequency of bleeding areas came as follows: the vault of inferior nasal meatus in 3783 cases(31.90%), the olfactory sulcus of middle turbinate in 3522 cases(29.70%), the posterior regions of middle meatus in 1349 cases(11.37%), the regions of deviation of nasal septum in 1065 cases(8.98%), the foremost regions of nasal cavity in 738 cases(6.22%), and the others or uncertain in 1403 cases(11.83%). Finally, we drew a concise map of distribution about epistaxis on the basis of the concealed bleeding areas and offending vessels. 151 of 152 patients(99.34%) could find out the bleeding sites accurately and stop the bleeding through minimally invasive radiofrequency ablation. CONCLUSION We drew a map of distribution about epistaxis in concealed areas so that it is convenient for us to seek out the bleeding sites. Rational use of nasal endoscopy to explore the sites of intractable epistaxis and minimally invasive radiofrequency are optimized mode of treatment.
10.Value of methylated Septin 9 detection in screening colorectal cancer in elderly people
Qingqing DING ; Hao ZHANG ; Haichen XU ; Xiaolin LI ; Yun SHAO ; Qiping XUE ; Weihao SUN
Chinese Journal of Geriatrics 2015;34(12):1348-1350
Objective To investigate the value of detecting methylated SEPT9 gene (mSEPT9) in serum and stool in screening colorectal cancer in elderly people.Methods Subjects were divided into three groups, the colorectal cancer group (n=82), the colorectal polyps group (n=80) and the healthy control group (n=100).Real-time quantitative polymerase chain reaction (PCR) was used to detect mSEPT9 in peripheral blood and feces.The relationship between mSEPT9 and clinical and pathological characteristics of colorectal cancer was analyzed.The agreement between serum and stool results was analyzed.Results The positive rate of serum mSEPT9 was 73.2% in the colorectal cancer group, 6.3% in the colorectal polyps group and 4.0% in the healthy control group, with statistical significance between the colorectal cancer group and the other two groups (P<0.01).The sensitivity and specificity for plasma mSEPT9 detection in screening colorectal cancer were 73.2 % and 95.6%, respectively.The positive rate was higher in patients with tumor maximum diameter over 3.0 cm, invasion of the entire serosa layer, lower differentiation or advanced clinical staging (P<0.05).The detection results of plasma mSEPT9 were in complete agreement with those of stool mSEPT9 from the same patients.Conclusions The expression of mSEPT9 is high in elderly patients with colorectal cancer and has a high sensitivity and specificity for PCR detection.Complete agreement can be seen in results from plasma and feces.Detecting mSEPT9 can be a valuable approach to screening colorectal cancer in the elderly.