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Bouveret syndrome masquerading as a gastric mass-unmasked with endoscopic luminal laser lithotripsy:A case report

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World Journal of Clinical Cases 2020年第22期8卷 5701-5706页

作者： Swetha Parvataneni Harshit S Khara david l diehl Department of Internal Medicine Geisinger Lewistown HospitalLewistownPA 17044United States Department of Gastroenterology and Hepatology Advanced EndoscopyGeisinger Health systemDanvillePA 17822United States Department of Gastroenterology and Nutrition Geisinger Medical CenterDanvillePA 17822United States

BACKGROUND Bouveret syndrome,also known as gallstone ileus,is a rare form of gastric outlet obstruction accounting for 1%-3%of *** condition is most often reported in *** diagnosis can be challenging and is often missed due to atypical presentations,which occasionally mimic gastric outlet obstruction symptoms such as nausea,vomiting,loss of appetite and *** symptoms vary with stone *** stones are managed with a surgical approach,but this carries increased morbidity and *** the past decade,the endoscopic approach has emerged as an alternative mode of treatment,but it is generally unsuccessful in the management of larger-sized stones.A literature review revealed cases of successful endoscopic treatment requiring multiple sessions for stone sizes measuring up to about 4.5 *** we present a unique case of an elderly patient with Bouveret syndrome with a 5 cm stone mimicking a gastric mass and causing gastric outlet obstruction,who was successfully managed in a single session using a complete endoscopic approach with laser *** SUMMARY An 85-year-old female patient presented with 1-month history of intermittent abdominal pain,vomiting,decreased appetite and weight *** abdominal computed tomography showed a 4.5 cm×4.7 cm partially calcified mass at the gastric pylorus causing gastric outlet *** showed an ulcerated fistulous opening and a large 5 cm impacted gallstone in the duodenal *** nets and baskets were used in an attempt to remove the stone,but this approach was *** her advanced age,poor physical condition and underlying comorbidities,she was deemed to be high-risk for ***,a minimally invasive approach using endoscopic laser lithotripsy was attempted and successfully treated the ***-procedure,the patient experienced complete resolution of her symptoms with no complications and was able to tolerate her *** was subsequently discharged home

关键词： Gastric outlet obstruction Bouveret syndrome laser lithotripsy Holmium laser lithotripsy Holmium and neodymium yttrium aluminum garnet lasers Case report

Esophageal stent fracture:case report and review of the literature

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World Journal of Gastroenterology 2014年第10期20卷 2715-2720页

作者： Harshit S Khara david l diehl Seth A Gross Department of Gastroenterology and Nutrition Geisinger Medical Center Danville PA 17822 United States Division of Gastroenterology NYU School of Medicine NYU Langone Medical Center New York NY 10028United States

Endoscopic esophageal stent placement is widely used in the treatment of a variety of benign and malignant esophageal *** expanding metal stents(SEMS)are associated with significantly reduced stent related mortality and morbidity compared to plastic stents for treatment of esophageal conditions;however they have known complications of stent migration,stent occlusion,tumor ingrowth,stricture formation,reflux,bleeding and perforation amongst others.A rare and infrequently reported complication of SEMS is stent fracture and subsequent migration of the broken *** have only been a handful of published case reports describing this *** this report we describe a case of a spontaneously fractured nitinol esophageal SEMS,and review the available literature on the unusual occurrence of SEMS fracture placed for benign or malignant obstruction in the *** fracture could be a potentially dangerous event and should be considered in a patient having recurrent dysphagia despite successful placement of an esopha-geal *** usually requires endoscopic therapy and may unfortunately require surgery for retrieval of a distally migrated *** recognition and prompt management may be able to prevent further problems.

关键词： Esophagus Self-expanding metal stent Stent complication Stent fracture Stent migration

Risk factors for colonoscopic perforation: A population-based study of 80118 cases

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World Journal of Gastroenterology 2013年第23期19卷 3596-3601页

作者： Uzair Hamdani Raza Naeem Fyeza Haider Pardeep Bansal Michael Komar david l diehl H lester Kirchner Department of Gastroenterology Geisinger Medical CenterDanville PA 17822 United States Department of Gastroenterology Good Samaritan HospitalVincennes IN 47591 United States Central Indiana Gastroenterology Anderson IN 46016 United States Division of Medicine Gesinger Medical CenterDanville PA 17822 United States

AIM: To assess the incidence and risk factors associated with colonic perforation due to colonoscopy. METHODS: This was a retrospective cross-sectional study. Patients were retrospectively eligible for inclusion if they were 18 years and older and had an inpatient or outpatient colonoscopy procedure code in any facility within the Geisinger Health System during the period from January 1, 2002 to August 25, 2010. Data are presented as median and inter-quartile range, for continuous variables, and as frequency and percentage for categorical variables. Baseline comparisons across those with and without a perforation were made using the two-sample t -test and Pearson's χ2 test, as ***: A total of 50 perforations were diagnosed out of 80118 colonoscopies, which corresponded to an incidence of 0.06% (95%CI: 0.05-0.08) or a rate of 6.2 per 10000 colonoscopies. All possible risk factors associated with colonic perforation with a P -value lusion in a multivariable logbinomial regression model predicting 7-d colonic perforation. The final model resulted in the following risk factors which were significantly associated with risk of colonic perforation: age, gender, body mass index, albumin level, intensive care unit (ICU) patients, inpatient setting, and abdominal pain and Crohn's disease as indications for colonoscopy. CONClUSION: The cumulative 7 d incidence of colonic perforation in this cohort was 0.06%. Advanced age and female gender were significantly more likely to have perforation. Increasing albumin and BMI resulted in decreased risk of colonic perforation. Having a colonoscopy indication of abdominal pain or Crohn's disease resulted in a higher risk of colonic perforation. Colonoscopies performed in inpatients and particularly the ICU setting had substantially greater odds of perforation. Biopsy and polypectomy did not increase the risk of perforation and only three perforations occurred with screening colonoscopy.

关键词： Colonoscopic perforation Colon cancer Endosocopy

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina Hromada Patrick Heimel Markus Kerbl lászlóGál Sylvia Nürnberger Barbara Schaedl James Ferguson Nicole Swiadek Xavier Monforte Johannes C.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller david Hercher Department life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar El Baba Ali Tfaily Firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian Mustroph david Gimbel Jonathan Grossberg Daniel l.Barrow Matthew F.Gary Ali M.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA Center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy

TOPOlOGY AND CASCADING lINE OUTAGES IN POWER GRIDS

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Journal of Systems Science and Systems Engineering 2007年第2期16卷 202-221页

作者： david l. PEPYNE University of Massachusetts Amherst MA USA

Motivated by the small world network research of Watts ＆ Strogatz, this paper studies relationships between topology and cascading line outages in electric power grids. Cascading line outages are a type of cascading collapse that can occur in power grids when the transmission network is congested. It is characterized by a self-sustaining sequence of line outages followed by grid breakup, which generally leads to widespread blackout. The main findings of this work are twofold： On one hand, the work suggests that topologies with more disorder in their interconnection topology tend to be robust with respect to cascading line outages in the sense of being able to support greater generation and demand levels than more regularly interconnected topologies. On the other hand, the work suggests that topologies with more disorder tend to be more fragile in that should a cascade get started, they tend to break apart after fewer outages than more regularly interconnected topologies. Thus, as has been observed in other complex networks, there appears to be a tradeoff between robustness and fragility. These results were established using synthetically generated power grid topologies and verified using the IEEE 57 bus and 188 bus power grid test cases.

关键词： Power grid blackout cascading line failure complex networks robust yet fragile

OPTIMAl INVERSE lQG CONTROl FOR CERTAIN ODE AND PDE STATIONARY PROCESSES

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Journal of Systems Science & Complexity 2010年第3期23卷 584-599页

作者： david l.RUSSEll Department of Mathematics Virginia Tech

Following work carried out earlier on linear-quadratic optimal control for linear finitedimensional stationary systems we report,in this article,on extension of some of those results to certaininfinite dimensional systems;in particular a class of PDE systems of elliptic *** systems arestudied in the now familiar framework developed by *** and ***,specialized to asubclass of such systems important in a variety of *** an extended example this paperstudies an optimal redistribution problem in a groundwater flow system governed by Darcy's equation,presenting both analytic and computational work related to such problems.

关键词： Elliptic PDE linear feedback control stationary system.

Dislocation Creep Accommodated by Grain Boundary Sliding in Dunite

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Journal of Earth Science 2010年第5期21卷 541-554页

作者： Yonghong Zhao david l Kohlstedt School of Earth and Space Sciences Peking University Department of Geology and Geophysics University of Minnesota

To investigate the role of grain boundary sliding during dislocation creep of dunite, a series of deformation experiments were carried out under anhydrous conditions on fine-grained （-15 μm） samples synthesized from powdered San Carlos olivine and powdered San Carlos olivine＋1.5 vol.% MORB. Triaxial compressive creep tests were conducted at a temperature of 1 473 K and confining pressures of 200 and 400 MPa using a high-resolution, gas-medium deformation apparatus. Each sample was deformed at several levels of differential stress between 100 and 250 MPa to yield strain rates in the range of 10^-6 to 10^-4 s^-1. Under these conditions, the dominant creep mechanism involves the motion of dislocations, largely on the easy slip system （010）[100], accommodated by grain boundary sliding （gbs）. This grain size-sensitive creep regime is characterized by a stress exponent of n=3.4±0.2 and a grain size exponent of p=2.0±0.2. The activation volume for this gbs-accommodated dislocation creep regime is V＊=（26±3）×10^-6 m2·mol^-1. Comparison of our flow law for gbs-accommodated dislocation creep with those for diffusion creep and for dislocation creep reveals that the present flow law is important for the flow of mantle rocks with grain sizes of 〈100μm at differential stresses 〉20 MPa. Hence, gbs-accommodated dislocation creep is likely to be an important deformation mechanism in deep-rooted, highly localized shear zones in the lithospheric upper mantle.

关键词： grain boundary sliding creep olivine flow law.

MEMS-in-the-lens architecture for a miniature high-NA laser scanning microscope

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light(Science & Applications) 2019年第1期8卷 665-675页

作者： Tianbo liu Milind Rajadhyaksha david l.Dickensheets Electrical and Computer Engineering Department Montana State UniversityBozemanMT 59715USA Dermatology Department Memorial Sloan Kettering Cancer CenterNew YorkNY 10022USA

laser scanning microscopes can be miniaturized for in vivo imaging by substituting optical microelectromechanical system(MEMS)devices in place of larger *** emergence of multifunctional active optical devices can support further miniaturization beyond direct component replacement because those active devices enable diffraction-limited performance using simpler optical system *** this paper,we propose a catadioptric microscope objective lens that features an integrated MEMS device for performing biaxial scanning,axial focus adjustment,and control of spherical *** MEMS-in-the-lens architecture incorporates a reflective MEMS scanner between a low-numerical-aperture back lens group and an aplanatic hyperhemisphere front refractive element to support high-numerical-aperture *** implemented this new optical system using a recently developed hybrid polymer/silicon MEMS three-dimensional scan mirror that features an annular aperture that allows it to be coaxially aligned within the objective lens without the need for a beam *** optical performance of the active catadioptric system is simulated and imaging of hard targets and human cheek cells is demonstrated with a confocal microscope that is based on the new objective lens design.

关键词： scanning scanner mirror