1.The initial application of 3.0T high field intensity intraoperative magnetic resonance for cranial tumor
Yunjun LI ; Wende LI ; Hao ZHAO ; Bin YU ; Jinbao GAO ; Lihua CHEN ; Qun WEI ; Ruxiang XU
Chinese Journal of Postgraduates of Medicine 2012;(32):27-30
Objective To study the initial application of 3.0T high field intensity intraoperative magnetic resonance(iMR)for cranial tumors.Methods Forty-three patients with cranial tumors including 23 glioma cases,12 pituitary tumor cases,3 brain stem cavernous hemangioma cases,2 meningioma cases,2metastatic tumor cases,1 neurilemmoma case,received operation examined with GE Signa HDX 3.0T iMR system.The operation process and influence of iMR were reviewed.Results In 43 patients,average iMR examination was 1.3(1-3)times.In 16 patients the first iMR examination revealed tumor remnants,and in 13 of them continued surgical interventions and complete resection.The rate of complete resection was increased from 63%(27/43)to 93%(40/43).No complications related to iMR occurred.Conclusion 3.0T high field intensity iMR can provide accurate positioning and real-time navigation for the surgery,increase the rate of complete resection,improve the accuracy and safety of cranial tumor resection,and decrease complications.
2.Differentiation of Benign and Malignant Biliary Stricture Using Magnetic Resonance Cholangiopancreatography Combined with Dynamic Contrast Enhanced CT
Bin SHI ; Ying LIU ; Feiyan ZENG ; Changxin WANG ; Yunjun XU ; Hanmei HUANG
Chinese Journal of Medical Imaging 2015;23(8):597-601,613
Purpose The diagnosis, treatment and prognosis of benign and malignant biliary stricture are significantly different. This study aims to evaluate the quantitative analysis of biliary structures using magnetic resonance cholangiopancreatography (MRCP) combined with dynamic contrast enhanced CT (DCE-CT).Materials and Methods The quantitative parameters of MRCP and DCE-CT imaging data from 27 patients with benign biliary stricture (benign group) and 30 patients with malignant biliary stricture (malignant group) were retrospectively analyzed. The wall thickness, stricture length and diameter, proximal ductal dilatation and degree of enhancement in two groups were compared, and its correlation was analyzed to evaluate the accuracy of MRCP and DCE-CT.Results There were significant differences in wall thickness [(3.2±2.0) mmvs (2.1±0.6) mm], stricture length [(15.8±8.1) mmvs (9.5±6.5) mm] and diameter [0 mmvs (2.0±0.9) mm], proximal ductal dilatation and the degree of enhancement [(12.7±3.6) mmvs (9.3±2.7) mm] between the two groups (t=2.825, 3.270, 4.025,P<0.001;Z=-3.909,P<0.001). Multivariable stepwise regression analysis showed that the wall thickness and diameter, and the CT HU in portal venous and equilibrium phases combined with CT plain scanning were significant predictors of malignant biliary strictures (t=-6.424-2.309,P<0.05). The sensitivity, specificity, inter-modality agreement and Youden index of MRCP and DCE-CT in diagnosing 57 patients with biliary stricture were 96.67%, 100.00%, 98.25% and 0.97, respectively; with statistical significance in predicting benign and malignant biliary stricture (AUC=0.994,P<0.001).Conclusion Using MRCP and DCE-CT, the wall thickness and diameter of the stricture, and the difference in CT HU in portal venous and equilibrium phases combined with CT plain scanning are valuable in differential diagnosis of benign and malignant biliary stricture.
3.Prevention and cure of intracranial infections following posterior fossa craniotomy
Yongchun LUO ; Jiazhen QIN ; Hongtian ZHANG ; Yiwu DAI ; Ruxiang XU ; Yunjun LI
Chinese Journal of Postgraduates of Medicine 2010;33(14):16-18
Objective For decreasing the infected rate,the prevention and cure methods of intracranial infections following posterior fossa craniotomy were study. Methods Twenty-eight patients with the intracranial infections following posterior fossa craniotomy were examined by lumbar puncture,and analyzed cerebrospinal fluid with routine examination and reference to the bacteriological data and drug sensitive tests. All the patients were treated with high dosage sensitive antibiotics, and draining continually the infected cerebrospinal fluid by lumbar puncture catheterization and injected small dosages of antibiotics into intraspinal for most cases. Results Twenty-eight patients had intracranial hypertension by lumbar puncture examination, outcome of cerebrospinal fluid culture indicated that 17 cases had bacteria growth and 11 cases had no bacteria. The intracranial infection was controlled effectively,and 96.4%(27 cases) were cured, 1 case dead of systemic failure. Conclusions Strict aseptic techniques,reduce operative time,decrease intracranial place of foreign matters, such as gelfoam, hemostatic gauze and artificial implants, could reduce the possibilities of intracranial infections. Appropriate antibiotics selection,lumbar puncture catheterization and intraspinal administration of antibiotics can cure intracranial infections effectively.
4.Microsurgical management of petroclival meningiomas combined trans-subtemporal and suboccipital retrosigmoid keyhole approach
Lihua CHEN ; Yi YANG ; Qun WEI ; Yunjun LI ; Wende LI ; Jinbao GAO ; Bin YU ; Hao ZHAO ; Ruxiang XU
Journal of Peking University(Health Sciences) 2016;48(4):738-742
Objective:With the development of modern skull base minimally invasive technology mature and neural radio surgery techniques,it is necessary to re-examine the therapeutic strategy for the treat-ment of petroclival meningiomas.To sum up the operative experience and methods in microsurgical resec-tion of petroclival meningiomas by the combining trans-subtemporal and suboccipital retrosigmoid keyhole approach.To explore the minimally invasive operation approach of petroclival meningiomas,to raise the removal degree and to improve the postoperative result using this approach.Methods:The clinical data of the consecutive 21 patients with the petroclival meningiomas were reviewed retrospectively.The meth-od,degree of tumor resection,techniques of the combining keyhole approach,Karnofsky performance score (KPS)before and after operation were also analyzed.The neuronavigation guided operation was performed in 9 cases,and 12 cases were operated in the neuroelectrophysiological monitoring.Results:Total excision of the tumor resection (Simpson,Ⅰ -Ⅱlevels)was conducted in 18 cases (85.7%,18 /21),and 3 patients underwent close resection (Simpson Ⅲ level,14.3%,3 /21).Postoperative three-dimensional CT showed good lock bone flap restoration;Postoperative pathology confirmed meningioma. Postoperative cranial nerve dysfunction or new original nerve dysfunction were aggravated in 5 cases (23.8%),including transient trochlear nerve (3 cases),abducent nerve (1 case),and the motor branch of trigeminal nerve paralysis (1 case).Abducent nerve paralysis (1 case)appeared,with hearing impairment.After the 3-month follow-up,11 cases had the same KPS aspreoperation,7 cases improved,and 3 cases not improved.The KPS score was 77.14 ±23.12 on average,and there was no statistically significant difference compared with that before operation (P >0.05 ).The postoperative follow-up for half a year showed fluent speaking and writing in 19 cases (KPS 70 or higher),and general recovery in 2 cases (KPS <70).The postoperative follow-up for 3 -29 months showed no tumor recur-rence or progress.Conclusion:The combining trans-subtemporal and suboccipital retrosigmoid keyhole approach is simple,safe,and minimally invasive,and an ideal operation approach of petroclival menin-gioma.To master the operation skills and the intraoperative matters needing attention in the operation,is favorable to improve the resection rate and curative effect.
5.Analysis of crossed cerebellar diaschisis after subacute phase of cerebral hemorrhage with CT perfusion imaging
Yue ZHANG ; Rui LI ; Jincheng WANG ; Haoli XU ; Shuailiang LIU ; Wenwen HE ; Xiaotao QIN ; Guoquan CAO ; Yunjun YANG ; Qichuan ZHUGE ; Weijian CHEN
Chinese Journal of Radiology 2017;51(8):561-567
Objective To analyze crossed cerebellar diaschisis(CCD) after subacute phase of spontaneous cerebral hemorrhage(SPSCH)and it's relevant factors with whole-brain CT perfusion(CTP) imaging. Methods Eighty-six patients diagnosed with unilateral SPSCH by CT were prospectively enrolled in our study from July 2015 to October 2016. Whole-brain CTP was performed in each patient.Cerebral blood flow(CBF), cerebral blood volume(CBV), mean transit time(MTT)and time-to-peak(TTP) inipsilateral and contralateral cerebellum were manually measured.The asymmetric indexs(AIs) were also calculated. Moreover, the volume of hematoma, the maximumarea of peri-hematomahypoperfusionin CBF and clinical factors(age, gender, time intervals from symptom onset)were analyzed,and NIHSS scores were used to evaluate the neurological status before patient admission, inspection, and discharge.CCD was rated positive when a unilateral supratentorial hematomawas appeared and an accompanying perfusion decrease was showed in the contralateral cerebellum on at least two sequential slices of CTP maps.All the individuals were divided into two groups including CCD-positive groupand CCD-negative group. The perfusion parameters (CBF, CBV, MTT, and TTP)between the contralateral and ipsilateral cerebellum were analyzed by the two-tailed paired t-test in CCD-positive group. The differences in the perfusion and clinical variables between the two groups were analyzed by the independent sample t-test and the Chi-squared test. Therelationships between the AI values and clinical or radiologic variables were assessed with Pearson correlation test. Results We found 35 CCD positive cases and 51 negative cases in the 86 patients.In CCD-positive groups, the perfusion values of cerebellumipsilateral and contralateral to the hematomawere as follows:CBF were (40.88±11.23) vs. (33.91±9.96) ml·100 g-1·min-1, CBV were (3.30±1.18) vs. (2.75±1.13) ml/100 g and TTP were (22.09±3.98) vs. (22.88±4.15) s, respectively, and there was statistical significance (t=10.231,8.223,-2.883,P<0.05).In CCD positive group, CBF, CBV, TTP, and MTT of the contralateral cerebellar hemisphere was changed in 35, 32, 26, and 16 cases,respectively.The AI value of CBF(AICBF)in CCD-positive group was (17.10±9.10)%, which was higher than that in the negative group (-0.95±17.01)%, there was statistical significance(t=6.367,P<0.05).The AI value of CBV(AICBV)was (17.43 ± 11.65)% in CCD-positive group, also significantly higher than that in negative group which was (1.55±21.06)%(t=4.477, P<0.05). No statistical difference(P>0.05)was found in hematoma location,hematoma volume, supratentorialhypoperfusion area and NIHSS scores(at admission, inspection)between CCD-positive and negative groups.The AICBF and AITTP showed linear correlation with time intervals in CCD-positive patients(P<0.05). Conclusions CCD is a common phenomenon in patients with SPSCH.Of all the perfusion parameters,CBF abnormalities are more common.The severity of CCD has a certain correlation with time intervals.There is no significant correlation between CCD and the clinical or radiological data(age, NIHSS scores,hematoma volume, and supratentorial hypoperfusion area).
6.Expression of Vitreoscilla hemoglobin improves recombinant lipase production in Pichia pastoris.
Xiaofeng WANG ; Yongchuan SUN ; Xuguang SHEN ; Feng KE ; Li XU ; Yun LIU ; Yunjun YAN
Chinese Journal of Biotechnology 2011;27(12):1755-1764
Yarrowia lipolytica lipase Lip2 (YlLip2) is an important industrial enzyme with many potential applications. To alleviate the dissolved oxygen (DO) limitation and improve YlLip2 production during high-cell density fermentation, the YlLip2 gene lip2 and Vitreoscilla hemoglobin (VHb) gene vgb were co-expressed in Pichiapastoris under the control of AOX1 and PsADH2 promoter, respectively. The PsADH2 promoter from Pichia stipitis could be activated under oxygen limitation. The SDS-PAGE and CO-difference spectrum analysis indicated that VHb and YlLip2 had successfully co-expressed in recombinant strains. Compared with the control cells (VHb-, GS115/9Klip2), the expression levels of YlLip2 in VHb-expressing cells (VHb+, GS115/9Klip2-pZPVT) under oxygen limitation were improved 25% in shake-flask culture and 83% in a 10 L fermentor. Moreover, the VHb+ cells displayed higher biomass than VHb- cells at lower DO levels in a 10 L fermentor. In this study, we also achieved a VHb-expressing clone harboring multicopy lip2 gene (GS115/9Klip2-pZPVTlip2 49#), which showed the maximum lipolytic activity of 33 900 U/mL in a 10 L fermentor under lower DO conditions. Therefore, it can be seen that expression of VHb with PsADH2 promoter in P. pastoris combined with increasing copies of lip2 gene is an effective strategy to improve YlLip2 production.
Bacterial Proteins
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biosynthesis
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genetics
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Fermentation
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Fungal Proteins
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biosynthesis
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genetics
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Lipase
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biosynthesis
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genetics
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Oxygen
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analysis
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pharmacology
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Pichia
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metabolism
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Protein Engineering
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Recombinant Proteins
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biosynthesis
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genetics
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Truncated Hemoglobins
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biosynthesis
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genetics
7.Clinical controlled study of neuroendoscope assisted microneurosurgery for epidermoid cysts of the posterior cranial fossa
Yunjun LI ; Juan FAN ; Hao ZHAO ; Wende LI ; Qun WEI ; Lihua CHEN ; Ruxiang XU
Chinese Journal of Neuromedicine 2014;13(9):947-949
Objective To summarize the experience of microsurgical treatment of posterior fossa epidermoid cyst in nearly five years,and to explore the effect of endoscopic assisted microsurgical treatment on posterior fossa epidermoid cysts.Methods A retrospective analysis of 49 patients with posterior fossa epidermoid cysts,admitted to our hospital from January 2008 to January 2013,was conducted.The controls were 20 patients treated only by micro-neurosurgery,and the other 29 were as observation subjects:the tumors were,first,mostly removed under micro-neurosurgery,and then,residual tumors were resected under neuroendoscopy.The operation time,complications and tumor residual rate were compared between the two groups.Results According to the different tumor location in posterior fossa,three surgical approaches were adopted:suboccipital posterior midline approach,suboccipital posterior sigmoid sinus approach and supratentorial infratentorial combined approach.Postoperative complications were aseptic meningitis,transient cranial nerve palsy and delayed intracranial hematoma.There was statistical significance between two surgical methods in residual tumor rate and incidence of complications (P<0.05),while no statistical significance in operation time was noted between the two groups (P>0.05).Conclusion With the assistant of neuroendoscopy,tumor removal rate of posterior fossa epidermoid cyst would be improved obviously and the incidence of complications would be decreased.
8.Surgical strategies and techniques of petroclival meningiomas by trans-subtemporal combined with suboccipital retrosigmoid keyhole approaches
Lihua CHEN ; Ruxiang XU ; Qun WEI ; Yunjun LI ; Wende LI ; Jinbao GAO ; Bin YU ; Hao ZHAO
Chinese Journal of Neuromedicine 2017;16(4):381-386
Objective To summary the microsurgical strategies and techniques of petroclival meningiomas by trans-subtemporal combined with suboccipital retrosigrnoid keyhole approaches to raise the removal rate and improve the prognosis.Methods The clinical data of consecutive 26 patients with petroclival meningiomas,admitted to our hospital from January 2011 to December 2015 and accepted microsurgical treatment,were reviewed retrospectively;7 of them were guided by neuronavigation,8 were performed under neuroelectrophysiological monitoring,and 11 were guided by neuronavigation combined intraoperative MRI or neuroelectrophysiological monitoring.The operative methods and techniques,tumor resection rate and Kamofsky performance scale (KPS) scores before and after operation were analyzed.Results Of all patients who underwent surgical treatment by trans-subtemporal combined with suboccipital retrosigmoid keyhole approaches,gross total tumor resection (Simpson Ⅰ-Ⅱ) was achieved in 23 patients (88.5%),subtotal (Simpson Ⅲ-Ⅳ) in 3 patients (1 1.5%).Six patients (23.1%) had cranial nerve deficit postoperatively.No mortality which related with operation was noted.Patients were followed up for 3-35 months,23 patients had KPS scores ≥70,and 3 patients had KPS <70;no tumor recurrence or progression was noted.Conclusion The trans-subtemporal combined with suboccipital retrosigmoid keyhole approaches are safe,effective and minimally invasive for resection of petroclival meningiomas;mastering the operation strategies and intraoperative skills is conducive to improve the efficacy of surgery.
9.Lateral cervical lymph node mapping in papillary thyroid carcinoma: a prospective cohort study
Naisi HUANG ; Ben MA ; Qing GUAN ; Yunjun WANG ; Li ZHOU ; Wenjun WEI ; Zhongwu LU ; Shuwen YANG ; Weibo XU ; Jun XIANG ; Qinghai JI ; Yu WANG
Chinese Journal of Clinical Oncology 2018;45(20):1053-1056
Objective: To explore the value of nanoparticles (CN) in lateral cervical lymph node mapping in papillary thyroid carcinoma using carbon. Methods: Thyroid cancer patients with suspicious lymph node metastasis but without typical signs of metastatic disease from March 2016 to November 2017 in Fudan University Shanghai Cancer Center were prospectively included in the cohort. Neck dissection was performed in all patients (compartmentsⅡ-Ⅴ). Suspicious lateral lymph node metastasis was identified using pre-operative ultrasound or computed tomography. CN were used for lymph node mapping during surgery. Results: A total of 70 surgeries were performed in 67 patients, among which 57 were found to have lateral lymph node metastasis (81.4%). The median number of CN-dyed lateral lymph nodes was 6. Compartment IV had the highest number of CN-dyed positive lymph nodes as well as the highest rate of metastasis, followed by compartmentⅢ. In compartmentsⅢandⅣ, the incidence of lymph node metastasis was significantly higher in the CN-dyed group than in the CN-undyed group (P<0.001). When the final pathology of neck dissection was set as the gold standard, lateral CN-dyed lymph node biopsy was found to have a sensitivity of 86.0%; its negative predictive value was 61.9% and its overall accuracy was 88.6%. Conclusions:Injection of CN during surgery was a potential method of mapping lateral lymph nodes in papillary thyroid carcinoma. CompartmentⅢ-ⅣCN-dyed lymph node biopsy had a satisfactory sensitivity and thus, served as a reasonable range for lymph node biopsy.
10.Recent advances in enzyme immobilization.
Caixia KE ; Yanli FAN ; Feng SU ; Li XU ; Yunjun YAN
Chinese Journal of Biotechnology 2018;34(2):188-203
Enzyme is an efficient and green biocatalyst, and widely used in many areas. Immobilized enzyme is superior to its free form in a variety of properties. Enzyme immobilization studies started in the 1970s in China. Till now, immobilized enzymes are widely applied in the fields of food, medical, energy, environmental management, among others. However, there are still some defects such as no universal method and the high cost. Therefore, based on the relatively mature traditional immobilization technologies, efforts have been made to innovate immobilization technologies. As a result, many new immobilization technologies focusing on new carriers and methods are continuously generated. Coupling with more than ten years' study on enzyme immobilization, we present here recent development and application of new immobilization technologies, as well as suggestions to future development of immobilization technology.