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Changes in neurological and pathological outcomes in a modified rat spinal cord injury model with closed canal

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Neural Regeneration Research 2020年第4期15卷 697-704页

作者： Xin Sun Xing-Zhen Liu Jia Wang Hai-Rong Tao Tong Zhu Wen-Jie Jin Kang-Ping Shen Shanghai Key Laboratory of Orthopedic Implants Department of Orthopedic SurgeryShanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Pathology Shanghai Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

Most animal spinal cord injury models involve a laminectomy,such as the weight drop model or the transection model.However,in clinical practice,many patients undergo spinal cord injury while maintaining a relatively complete spinal canal.Thus,open spinal cord injury models often do not simulate real injuries,and few previous studies have investigated whether having a closed spinal canal after a primary spinal cord injury may influence secondary processes.Therefore,we aimed to assess the differences in neurological dysfunction and pathological changes between rat spinal cord injury models with closed and open spinal canals.Sprague-Dawley rats were randomly divided into three groups.In the sham group,the tunnel was expanded only,without inserting a screw into the spinal canal.In the spinal cord injury with open canal group,a screw was inserted into the spinal canal to cause spinal cord injury for 5 minutes,and then the screw was pulled out,leaving a hole in the vertebral plate.In the spinal cord injury with closed canal group,after inserting a screw into the spinal canal for 5 minutes,the screw was pulled out by approximately 1.5 mm and the flat end of the screw remained in the hole in the vertebral plate so that the spinal canal remained closed;this group was the modified model,which used a screw both to compress the spinal cord and to seal the spinal canal.At 7 days post-operation,the Basso-Beattie-Bresnahan scale was used to measure changes in neurological outcomes.Hematoxylin-eosin staining was used to assess histopathology.To evaluate the degree of local secondary hypoxia,immunohistochemical staining and western blot assays were applied to detect the expression of hypoxia-inducible factor 1α(HIF-1α)and vascular endothelial growth factor(VEGF).Compared with the spinal cord injury with open canal group,in the closed canal group the Basso-Beattie-Bresnahan scores were lower,cell morphology was more irregular,the percentage of morphologically normal neurons was lower,the percentages of HIF-1α-and VEGF-immunoreacti

关键词： Basso-Beattie-Bresnahan scores closed spinal canal HIF-1α hypoxia model nerve regeneration open spinal canal rat secondary injury spinal cord injury VEGF

Post-inflammatory acquired atresia of the external auditory canal

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Journal of Otology 2019年第4期14卷 149-154页

作者： Michel Kmeid Jade Nehme School of Medicine Lebanese UniversityBeirutLebanon Lebanese University Department of OtolaryngologyHead and Neck SurgeryBeirutLebanon

Acquired atresia of the external auditory canal(EAC)is a rare cause of conductive hearing loss.It has been traditionally classified into 4 categories:traumatic,post-operative,neoplastic and inflammatory.Post-inflammatory acquired auditory canal atresia is thought to be the result of chronic and repetitive infectious bouts affecting the auditory canal.Nevertheless,the underlying pathophysiology of this disorder is yet to be fully elucidated.Current data fail to clearly state the impact that certain underlying systemic disorders may have on the EAC.The possible association to metabolic disturbances such as iron deficiency is also emphasized.In the light of these findings,this analysis can be used to improve the classification of this entity thereby standardizing the assessment of therapeutic approaches.

关键词： Stenosing external otitis Meatal atresia External auditory canal Conductive hearing loss canaloplasty

The problem of fluid-dynamics in semicircular canal

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Science China Mathematics 2000年第5期43卷 517-526页

作者：徐明瑜谭文长 Institute of Mathematics and Systematical Science Research Center for Biomedical Engineering Shandong University Jinan 250100 China Department of Mechanics and Engineering Science Peking University Beijing 100871 China

An analytical solution with high accuracy which holds for any values of E for fluid-dynamics model eguation in a single semicircular canal presented by Buskirk and his co-workers has been ob-tained. it not only includes ali of the results of Buskirk et al. but also covers three possible kinds of dy-namical response modes in practice. The theoretical results are in betler agreement with those of ex-perimental observations. This investigation has laid a reliable theoretical foundation for quantitatively understanding fluid-dynamics in semicircular canal, especially fluid dynamical response. The distribu-tion of the velocity of the endolymph in semicircular canal is given. A nonstandard method of the in-verse Laplace transform is presented.

关键词： semicircular canal fluid dynamics analytical solution frequency response impulse response non-standard inverse Laplace transform.

Temporal bone anatomy characteristics in superior semicircular canal dehiscence

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Journal of Otology 2017年第4期12卷 185-191页

作者： Marrigje A. de Jong David J. Carpenter David M. Kaylie Erin G. Piker Dennis O. Frank-Ito Department of Otorhinolaryngology/Head and Neck Surgery Hadassah Hebrew University Hospital Jerusalem Israel Division of Head and Neck Surgery & Communication Sciences Duke University Medical Center Durham NC USA Department of Communication Sciences and Disorders James Madison University Harrisonburg VA USA Computational Biology & Bioinformatics Duke University Durham NC USA Department of Mechanical Engineering and Materials Science Duke University Durham NC USA

Introduction: Superior semicircular canal dehiscence(SCD) remains difficult to diagnose despite advances in high-resolution computed tomography(HRCT) imaging. We hypothesize possible associations between gross temporal bone anatomy and sub-millimeter pathology of the semicircular canals, which may supplement imaging and clinical suspicion. This pilot study investigates differences in gross temporal bone anatomic parameters between temporal bones with and without SCD.Methods: Records were reviewed for 18 patients referred to an otology clinic complaining of dizziness with normal caloric stimulation results indicative of non-vestibular findings. Eleven patients had normal temporal bone anatomy while seven had SCD. Three-dimensional reconstruction of every patient's temporal bone anatomy was created from patient-specific computational tomography images. Surface area(SA),volume(V), and SA to V ratios(SA:V) were computed across temporal bone anatomical parameters.Results: SCD temporal bones have significantly smaller V, and larger temporal bone SA. Mean(±SD) V was 21,484 ± 3,921 mm^3 in temporal bones without SCD and 16,343 ± 34,471 mm^3 for those with SCD. Their respective SA were 13,733 ± 1,603 mm^2 and 18,073 ± 3,002 mm^2.Temporal bone airspaces and lateral semicircular canals did not demonstrate significant differences where SCD was and was not present. Plots of MV_(warm)response against computed SCD temporal bone anatomic parameters(SA, V and SA:V) showed moderate to strong correlations:temporal bone SA:V(r= 0.64), temporal bone airspace V(r= 0.60), temporal bone airspace SA(r= 0.55), LSCC SA(r= 0.51), and LSCC-toTM Distance(r= 0.65).Conclusions: This analysis demonstrated that SCD is associated with decreased temporal bone volume and density. The defect in SCD does not appear to influence caloric responses.

关键词： Temporal bone Anatomy Superior canal dehiscence Superior semicircular canal dehiscence

Application of high resolution computer tomography in external ear canal cholesteatoma diagnosis

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Journal of Otology 2018年第1期13卷 25-28页

作者： Yubin Chen Peng Li Department of Otolaryngology Head and Neck Surgery The Third Affiliated Hospital of Sun Yat-Sen University

Objective: To evaluate High Resolution Computer Tomography(HRCT) in the diagnosis of external ear canal cholesteatoma.Methods: In this retrospective study, HRCTs of 27 patients with external ear canal cholesteatoma were reviewed. The changes in the external ear canal, tympanic membrane(TM), scutum, tympanum and mastoid were measured and categorized.Results: Fourteen patients showed no or mild destruction in the external ear canal(stage Ⅰ group). Eight patients had obvious enlargement in the external ear canal(stage Ⅱ group) but showed limited destructions of the mastoid bone and no damage of the tympanums. Five patients had serious destruction of the mastoid bone and damage of the tympanum(stage Ⅲ group). All patients in the stage Ⅲ group showed a compression of manubriums and TMs, with 3 having damages on ossicular chain. Bone destruction of the vertical section of facial nerve canal was discovered in one case in the stage Ⅲ group.Conclusion: HRCT can provide detail information about the extent of external ear canal cholesteatoma. Such information can be used to identify special situations with serious complications and to differentiate external ear canal cholesteatoma from middle ear cholesteatoma.

关键词： External ear canal Cholesteatoma Computer tomography

Qualitative analysis of the Dix-Hallpike maneuver in multi-canal BPPV using a biomechanical model: Introduction of an expanded Dix-Hallpike maneuver for enhanced diagnosis of multi-canal BPPV

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2017年第3期3卷 163-168页

作者： Henri Traboulsi Michael Teixido Christiana Care Health Systems NewarkDEUSA Department of Otolaryngology University of PennsylvaniaPAUSA Department of Otolaryngology Thomas Jefferson UniversityPAUSA

Introduction/Objective:Multiple canal BPPV can be a diagnostic challenge to the clinician.This is due in part to the complex anatomy of the labyrinth but also to complex and often simultaneous ocular responses that result from stimulation of multiple canals during traditional diagnostic testing.Our objective was to analyze the Dix-Hallpike maneuver used in the diagnosis of BPPV to look for patterns of simultaneous canal response and to develop a diagnostic maneuver that will allow separation of canal responses in multiple canal BPPV.Methods:A previously created and published 3D biomechanical model of the human labyrinths for the study of BPPV was used to analyze and compare the position and movement of otoliths in the Dix-Hallpike maneuver as well as in a proposed expanded version of the traditional DixHallpike maneuver.Results:The traditional Dix-Hallpike maneuver with the head hanging may promote movement of otoliths in 5 of the six semicircular canals.The Dix-Hallpike maneuver with the head lowered only to the horizontal position allows for otoconia in only the lowermost posterior canal to fall to the most gravity dependent position.This position allows for minimal or no movement of otoconia in the contralateral posterior canal,or in either superior canal.Turning the head ninety degrees to the opposite side while still in the horizontal position will provoke otolith movement in only the contralateral posterior canal.The superior canals can then be examined for free otolith debris by extending the neck to a head-hanging position.These positions may be assumed directly from one to the next in the lying position.There seems to be no advantage to sitting up between positions.Conclusion:The Dix-Hallpike maneuver may cause simultaneous movement of otoliths present in multiple canals and create an obstacle to accurate diagnosis in multi-canal BPPV.An expanded Dix-Hallpike maneuver is described which adds intermediate steps with the head positioned to the right and left in the horizontal position before head-hanging.T

关键词： Benign paroxysmal positional vertigo Dizziness Multiple canal Dix-Hallpike canalithiasis Biomechanical model

Simulating and validating the effects of slope frost heaving on canal bed saturated soil using coupled heat-moisture-deformation model

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International Journal of Agricultural and Biological Engineering 2017年第2期10卷 184-193页

作者： Wang Enliang Fu Qiang Liu Xingchao Li Tianxiao Li Jinling School of Water Conservancy and Civil Engineering Northeast Agricultural UniversityHarbin 150030China Heilongjiang Provincial Collaborative Innovation Center of Grain Production Capacity Improvement Northeast Agricultural UniversityHarbin 150030China Key Laboratory of High Efficient Utilization of Agricultural Water Resource of Ministry of Agriculture Northeast Agricultural UniversityHarbin 150030China

The lining canals in seasonal frozen soil areas can be severely damaged by frost heaving.The freezing and thawing contributes to the continual change of the temperature field and moisture field beneath lining canal,which will seriously affect the safe operation of the canal.In order to study the frost heaving damage mechanism of lining canal and to solve the associated engineering problems,the permafrost body was regarded as an elastomer,and a three-field,coupled,partial differential equation describing the temperature,moisture and deformation fields for a saturated two-dimensional canal bed was derived and established based on the Harlan model.The coupling equations were discretized using the finite element method in space and the finite difference method in time.The parameters were simplified appropriately based on compliance with the actual conditions and were simulated using finite element software.The results of a sample simulation showed that the simulated results and test results were basically consistent with variation laws,which proved the correctness of the numerical simulation theory and solution methods and the reliability of the calculation.The model can simulate the water,heat and deformation issues in the side slope of saturated canal bed soil in a seasonally frozen area and forecast freezing damage in the canals.

关键词： seasonally frozen area canal soil of the side slope coupling of water heat and deformation model

THE FLOW CONTROL IN canal TRANSPORTATION SYSTEM

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Journal of Hydrodynamics 1997年第1期9卷 34-41页

作者： Xu Zu-xin, Liu Sui-qingThe College of Environment Engineering ,Tongji University,Shanghai 200092, P. R. ChinaR. GuercioDepart, of Hydraulics,transportation and highway,University of Rome,Rome,00184,Italy

The canal flow control by the linear quadratic theory of automatic control theory is discussed in this paper. In the process of flow control,an optimal state estimator is used to feedback control gate motion. One dimension Saint-Venant flow equations are expanded by first Taylor series at demanded states. The control results of flow in the example canal show remarkable improvement compared to the case without optimal observer. By this control method, the waste of water will significantly be decreased and the efficiency of water transportation can be greatly increased. If the changes of flow discharges are less than 20%, the method is effective for flow control in canal.

关键词： flow control canal linear quadratic theory automatic control

Anal canal gastrointestinal stromal tumors:Case report and literature review

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World Journal of Gastroenterology 2014年第1期20卷 319-322页

作者： Nuno Carvalho Diogo Albergaria Rui Lebre Joo Giria Vitor Fernandes Helena Vidal Maria José Brito Department of General Surgery Garcia de Orta Hospital2801-951 AlmadaPortugal Department of Gastroenterology Garcia de Orta Hospital2801-951 AlmadaPortugal Department of Radiology Garcia de Orta Hospital2801-951 AlmadaPortugal Department of Pathology Garcia de Orta Hospital2801-951 AlmadaPortugal

Gastrointestinal stromal tumors(GIST)are an uncommon group of tumors of mesenchymal origin.GIST of the anal canal is extremely rare.At present,only 10cases of c-kit positive anal GIST have been reported in the literature.There is no widely accepted treatment approach for this neoplasia.Literature is sparse on imaging evaluation of anal canal GIST,usually described as a lesion in the intersphincteric space.We describe the case of a 73-year-old man with a mass in the anal canal,and no other symptoms.Endoanal ultrasound and magnetic resonance imaging showed a well circumscribed solid nodule in the intersphincteric space.The patient was treated by local excision.Gross pathological examination showed a 7 cm×3.5 cm×3cm mass,and histological examination showed a proliferation of spindle cells,with prominent nuclear palisading.The mitotic count was of 12 mitoses/50 HPF.The tumor was positive for KIT protein,CD34 and vimentin in the majority of cells,and negative for desmin and S100.A diagnosis of GIST,with high risk aggressive behavior was made.An abdomino-perineal resection was discussed,but refused.The follow-up included clinical evaluation and anal ultrasound.After 5 years the patient is well,with maintained continence and no evidence of local recurrence.

关键词： Gastrointestinal stromal tumors Anal canal Endoana