1.EXPERIMENTAL STUDY OF ONE-PIECE PHEMA KERATOPROSTHESIS IMPLANTATION IN ALKALI INJURED CORNEA IN RABBIT
Hua BAI ; Feng GAO ; Yifei HUANG
Medical Journal of Chinese People's Liberation Army 2001;0(12):-
Objective To evaluate the effect of a new one-piece PHEMA keratoprosthesis(Kpros) implanted in alkali burned rabbit corneas. Methods The experiment included two parts. In part one, the porous discs of PHEMA were inserted into the lamellar pockets of alkali-burned corneas and the results were observed clinically and histologically at various periods. In part two, seven one-piece Kpros were implanted into alkali burned rabbit corneas. The Kpros consisted of a central transparent optical area and a porous semi-transparent peripheral skirt. The surgical procedure was similar to that of penetrating keratoplasty. Clinical observations were carried out till 28 weeks. Results Both the porous discs and one-piece Kpros had been retained during the experiment. Severe complications as cataract, retro corneal membrane, retinal detachment and extrusion of material were not found until 28 weeks. There was no calcification in the samples, and inflammation was mild. Two weeks after implantation, fibroblasts and deposition of collagen were found in the pores of PHEMA discs. The fibroblasts in the pores look healthy and functionally active. The preliminary results were satisfactory. Conclusion This new one-piece Kpros had shown good biocompatibility. The porous peripheral skirt fuses well with the bed of burned cornea and proved to be stable. PHEMA materials is suitable for one-piece Kpros.
2.Selection and significance of lateral lymph node dissection in advanced low rectal cancer after neoadjuvant chemoradiotherapy
Yueming SUN ; Yifei FENG ; Dongsheng ZHANG
Chinese Journal of Digestive Surgery 2021;20(3):266-271
Lateral lymphatic drainage is one of the three important directions for low rectal cancer. Radical surgery of rectal cancer requires the dissection of lymph nodes along the drainage route which determines the extent of lymph node dissection. However, controversial arguments exist whether lateral lymph node belonging to the regional lymph node or the distant lymph node. This arguments has also brought the controversy about neoadjuvant chemoradiotherapy and lateral lymph node dissection, as well as the controversy about efficacy of neoadjuvant chemoradiotherapy on lateral metastatic lymph nodes. Combined with the preliminary clinical practices, the authors comprehensively analyze research advances at home and abroad, further elaborate the lateral lymph node metastasis of rectal cancer, the risk factors affecting lateral lymph node metastasis and tumor recurrence, and the evaluation of lateral lymph node by magnetic resonance imaging before and after chemoradiotherapy, et al, in order to investigate the selection and significance of lateral lymph node dissection in advanced low rectal cancer after neoadjuvant chemoradiotherapy.
3.Efficacy and Safety of Moxifloxacin in the Treatment of Acute Exacerbation of Chronic Bronchitis:A Me-ta-analysis
Lijin CHEN ; Lika YE ; Xia FENG ; Juan ZHOU ; Yifei WANG
China Pharmacy 2016;27(30):4236-4240
OBJECTIVE:To systematically review the efficacy and safety of Moxifloxacin(MFX)in the treatment of acute ex-acerbation of chronic bronchitis (AECB),and provide evidence-based reference for Tational use of MFX. METHODS:Retrieved from PubMed,EMBase,Cochrane Library,Medline,CBM,CJFD,VIP and Wanfang Database,the relevant conference proceed-ings and grey literature were also hand-searched,randomized controlled trials(RCT)about MFX(test group)versus other antibiot-ics (control group) in the treatment of AECB were collected. Meta-analysis was performed by using Rev Man 5.2 software with ITT analysis and PP analysis after literature selection,data extraction and quality evaluation. RESULTS:Totally 14 RCTs were in-cluded,involving 6 058 patients. Results of PP analysis showed,the clinical effective rate in test group was similar to that of con-trol group [RR=1.02,95%CI(1.00,1.04),P=0.06],while bacteria clearance rate was significantly higher than control group [RR=1.07,95%CI(1.04,1.11),P<0.001]. Results of ITT analysis showed,the clinical effective rate in test group was significantly high-er than control group [RR=1.03,95%CI(1.00,1.06),P=0.03],while there was no significant difference in the bacteria clearance rate [RR=1.02,95%CI(0.92,1.12),P=0.73] and the incidence of adverse reactions [RR=0.97,95%CI(0.87,1.08),P=0.52] be-tween 2 groups. CONCLUSIONS:The efficacy of MFX is not inferior to other antibiotics in the treatment of AECB,safety is simi-lar to other antibiotics.
4.The simulation of multiphase flow field in ventricular assist device and analysis of hemolytic capability
Tieyan LI ; Lin ZOU ; Yuanfeng XIN ; Yunzhen FENG ; Yifei HUA ; Feng WAN ; Zhongmin LIU
Chinese Journal of Thoracic and Cardiovascular Surgery 2021;37(2):98-103
Objective:The hemolytic prediction model of the axial flow impeller blood pump is carried out by using a computational fluid dynamics(CFD) multiphase flow model.Methods:The hydrodynamic performance of the pump and the flow field in the pump, and the shear stress distribution are analyzed. A hemolytic prediction model based on the shear stress is built based on the calculation results. Hemolysis tests in vitro were performed 6 times with fresh bovine blood. At each time, the flow of the ventricular assist device(VAD) is 5 L/min and the outflow tract pressure is 100 mmHg(13.3kPa). According to the tests, the plasma free hemoglobin(FHB) content and the hematocrit(HCT) are measured every half hour. At the end of each experiment Normal Index of Hemolysis(NIH) is calculated.Results:The average of NIH is 0.0055 g/100L, almost identical with that obtained from the hemolytic prediction model.Conclusion:Multiphase flow model can be used for quantitative predictions of the hemolytic behavior of a VAD. This method can be applied in the selection stage of a blood pump.
5.Prevention and treatment of hemorrhage after pancreaticoduodenectomy
Dafang ZHANG ; Shu LI ; Weihua ZHU ; Yifei FENG ; Shengmin ZHENG ; Jirun PENG ; Xisheng LENG
Chinese Journal of General Surgery 2009;24(9):732-735
Objective To analyze the prevention and treatment of postoperative hemorrhage after pancreaticoduodenectomy. Methods The clinical data of 142 patients undergoing pancreaticoduedenectomy from Jan 1995 to Dec 2008 were retrospectively analyzed. Results The incidence of postoperative hemorrhage was 14.1% (20/142), the mortality caused by this complication was 35% (7/20). Among these patients, intra-abdominal hemorrhage occurred in seven cases, and gastrointestinal hemorrhage occurred in 14 cases, with one case suffering both. There were three and four cases of early and delayed intra-abdominal hemorrhage respectively. Early and delayed gastrointestinal hemorrhage occurred in three and eleven cases respectively. Univariate analysis showed that operative blood loss, blood transfusion, infection and pancreatic fistula were significantly associated with postoperative hemorrhage. Multivariate analysis using Logistic regression identified two variables as independent factors associated with postoperative hemorrhage, namely, infection(OR=6.918) and pancreatic fistula(OR=3.948). Conclusions The incidence and mortality of hemorrhage after pancreaticoduodenectomy is still high. Skillful operation and prevention of pancreatic fistula, infection and stress ulcer are the key paints for reducing postoperative hemorrhage. Proper treatments should be used according to the site, onset and severity of hemorrhage.
6.Cooperative therapeutic effects of herpes simplex virus thymidine kinase gene/ganciclovir system and chemotherapeutic agents on prostate cancer in vitro.
Yifei, XING ; Yajun, XIAO ; Gongcheng, LU ; Fuqing, ZENG ; Jun, ZHAO ; Ping, XIONG ; Wei, FENG
Journal of Huazhong University of Science and Technology (Medical Sciences) 2006;26(5):610-3
The killing effects of herpes simplex virus thymidine kinase gene/ganciclovir (HSV-tk/GCV) approach by the addition of several commonly clinical chemotherapeutic agents on hormone refractory prostate cancer (HRPC) cells PC-3m were investigated. After transferring of the HSV-tk gene into PC-3m cells, mRNA and protein expression of HSV-tk was detected by reverse-transcript polymerase chain reaction (RT-PCR) and strept avidin-biotin complex (SABC) immunohistochemical method. The killing effect of GCV, cisplatin (CDDP), etoposide (VP-16), vincristine (VCR), methotrexate (MTX), 5-fluorouracil (5-Fu), and suramin on PC-3m cells was evaluated by morphological assessment analysis, trypan blue exclusion assay and MTT assay respectively. Additionally, the cooperative effect of HSV-tk/GCV system combined with the above agents on the target cancer cells was determined by MTT. Furthermore, apoptosis and necrosis induced by GCV plus 5-Fu or suramin was analyzed by flow cytometry (FCM). The results showed that that there was HSV-tk mRNA and protein expression in pDR2-tk plasmid transduced PC-3m cell. Combination of GCV with VP-16, VCR, 5-Fu or suramin led to an enhanced cellular killing effect, but with CDDP resulted in a reduced one and with MTX in an approximate one. FCM revealed that synergistic use of GCV and 5-fu or suramin resulted in a rather large proportion of apoptosis and necrosis with the apoptosis index being 36.38% and 35.51%, and the proportion of necrosis being 33.05% and 28.87%, respectively. In conclusion, HSV-tk/CGV approach by addition of certain clinical available chemotherapeutic drugs brings on statistically significant enhanced cell killing over single-agent treatment. Our results highlight the potential for such new combination therapies for future treatments of HRPC.
7.Altered expression of connexin-43 and impaired capacity of gap junctional intercellular communication in prostate cancer cells.
Yifei, XING ; Yajun, XIAO ; FuQing, ZENG ; Jun, ZHAO ; Chuanguo, XIAO ; Ping, XIONG ; Wei, FENG
Journal of Huazhong University of Science and Technology (Medical Sciences) 2007;27(3):291-4
Connexin-43 (Cx43) expression in prostate cancer (PCa) cells and the potency of gap junctional intercellular communication (GJIC) in the cells were investigated, with an attempt to elucidate the reason why the so-called "bystander effect" mediated by thymidine kinase (TK) suicide gene therapy on PCa cells is not of significance and to explore the role of GJIC in PCa carcinogenesis. mRNA and protein expression of Cx43 in a PCa cell line PC-3m was detected by reverse-transcription polymerase chain reaction (RT-PCR) and strapt-avidin-biotin-enzyme complex (SABC) immunohistochemical staining, and inherent GJIC of PC-3m cells was assayed by scrape-loading and dye transfer (SLDT) assay. The expression of Cx43 in human normal and malignant prostate tissues was determined by SABC immunohistochemistry as well. It was found that Cx43 mRNA and protein expression in PC-3m cells was slightly reduced as compared with positive controls and the location of Cx43 protein was aberrant in cytoplasm rather than on membrane. Assessment of paraffin sections demonstrated that the expression of Cx43 protein in PCa cells was abnormally located and markedly diminished as compared with normal prostatic epithelial ones, displaying a negative correlation to the pathological grade (chi2=4.025, P<0.05). Additionally, capacity of inherent GJIC in PC-3m cells was disrupted, which was semi-quantified as (+) or (-). It was indicated that both down-regulated expression of Cx43 mRNA and aberrant location of Cx43 protein participated in the mechanisms leading to deficient GJIC in PC-3m cells. Lack of efficient GJIC is a molecular event, which may contribute not only to limited extent of "bystander effect", but also to initiation and progression of prostatic neoplasm.
8.Characteristics of the cerebral vascular hemodynamic changes in acute stroke patients
Bosheng YANG ; Hang LIN ; Yifei HONG ; Guiqing WANG ; Yifeng CAO ; Chunhong FENG
Chinese Journal of Tissue Engineering Research 2005;9(9):228-229
BACKGROUND: The understanding about characteristics and variation trends of cerebral vascular hemodynamic indexes in high-risk stroke population,in prior and post-stroke period patients as well as in normal people,particularly the cerebral vascular hemodynamic index(CVHD) prior to stroke can improve diagnosis efficiency of stroke and increase sensitivity and specificity of stroke diagnosis.OBJECTIVE: To study the features of CVHD in acute stoke,in order to provide evidences for early evaluation and rehabilitation intervention.DESIGN: Case analysis and observational study based on patients.SETTING: A neurological department in a general hospital of military area command of Chinese PLA and a prevention and cure institute of cerebrovascular diseases.PARTICIPANTS: Totally 55 (male 38,female 17) inpatients in the Neurological Department of Fuzhou General Hospital of Chinese PLA from June to December 2001 were enrolled in the study.METHODS: CVHD was measured during the first week after onset and the data were analyzed.MAIN OUTCOME MEASURES: The CVHD,blood pressure and cerebral vascular hemodynamic parameters.RESULTS: The CVHD of each patient is below 75,median 32.5. The mean velocity,blood flow,maximum velocity,minimum velocity and difference between diastolic and critical pressures were lower than corresponding ones of healthy men in seventies( P < 0.01 ). And the pulse wave velocity,peripheral resistance,specific impedance and critical pressure increased( P < 0. 01).CONCLUSION: During the first week after stroke,the CVHD decreases and many hemodynamic parameters alters significantly. Examination of CVHD can reveal cerebral circulation insufficiency or predict an attack of cerebral stroke.
9.Effects of Felodipine on Blood Vessel Endothelial Function in Patients with Benign Prostatic Hyperplasia Complicating Essential Hypertension
Yan LIU ; Aiwu MA ; Cunlong WANG ; Zongcheng FENG ; Yifei LIU ; Ye WANG
China Pharmacy 2005;0(14):-
OBJECTIVE:To observe the effects of felodipine on blood vessel endothelial function in patients with benign prostatic hyperplasia(BPH) complicating essential hypertension(EH).METHODS:Fifty five patients with BPH complicating EH were assigned to receive 5mg felodipine orally qd for 6 weeks,with levels of endothelin-1(ET-1),nitrous oxide(NO) and von Wilebrand factor(vWF),brachial artery flow-mediated dilatation(FMD) function,the maximum urine flow rate,the average urine flow rate and International Prostate Symptom Score(I-PSS) determined before and after treatment.Meanwhile levels of ET-1,NO and vWF and FMD in 37 normal healthy males were determined.RESULTS:In the treatment group compared with normal control group there were significant differences in levels of ET-1,NO and vWF and FMD(P0.05).There were significant differences in ET-1,NO and vWF levels and FMD after treatment as compared with before treatment(P
10.Precision of digital impressions with TRIOS under simulated intraoral impression taking conditions
Xin YANG ; Yifei SUN ; Lei TIAN ; Wenjie SI ; Hailan FENG ; Yihong LIU
Journal of Peking University(Health Sciences) 2015;(1):85-89
Objective:To evaluate the precision of digital impressions taken under simulated clinical impression taking conditions with TRIOS and to compare with the precision of extraoral digitalizations . Methods:Six #14 -#17 epoxy resin dentitions with extracted #16 tooth preparations embedded were made.For each artificial dentition , ( 1 ) a silicone rubber impression was taken with individual tray , poured with type IV plaster ,and digitalized with 3Shape D700 model scanner for 10 times;(2) fastened to a dental simulator , 10 digital impressions for each were taken with 3Shape TRIOS intraoral scanner .To assess the precision , best-fit algorithm and 3 D comparison were conducted between repeated scan models pairwise by Geomagic Qualify 12.0, exported as averaged errors (AE) and color-coded diagrams.Non-parametric analysis was performed to compare the precisions of digital impressions and model images .The color-coded diagrams were used to show the deviations distributions .Results:The mean of AE for digital impressions was 7.058 281 μm, which was greater than that of 4.092 363 μm for the model images (P<0.05).However, the means and medians of AE for digital impressions were no more than 10 μm, which meant that the consistency between the digital impressions was good .The deviations distribution was uniform in the model images ,while nonuniform in the digital impressions with greater deviations lay mainly around the shoulders and interproximal surfaces .Conclusion:Digital impressions with TRIOS are of good precision and up to the clinical standard .Shoulders and interproximal surfaces scanning are more difficult.