C-arm-based mobile computed tomography: a comparison with established imaging on the basis of simulated treatments of talus neck fractures in a cadaveric study.

OBJECTIVE: To analyse the image quality and diagnostic effectiveness of a new C-arm-based 3D imaging method (C-arm-CT) for intraoperative evaluation of screw osteosyntheses adjacent to a peripheral joint. MATERIALS AND METHODS: Insertion of screws into four cadaveric specimens simulated the surgical treatment of talus neck fractures. Ten orthopedic surgeons and 10 radiologists evaluated X-ray, C-arm fluoroscopy, C-arm-CT and CT images. RESULTS: The best image quality was obtained with X-rays (p < 0.001), followed by C-arm fluoroscopy (2D) and CT, with the C-arm-CT (3D) being rated lowest (p < 0.001). The most correct diagnoses were obtained with CT and C-arm-CT (with no statistical difference between them), while C-arm-fluoroscopy was inferior (p < 0.001) and X-rays were the worst (p < 0.05). CONCLUSIONS: Even if the image quality of C-arm-CT is definitely inferior to that of CT, screw misplacements can be reliably detected using C-arm-CT. As compared to the current standard procedures (intraoperative fluoroscopy and postoperative radiography), C-arm-CT performed better. C-arm-CT is ideally suited to the intraoperative diagnosis of high-contrast inquiries like bone fragments and OS material, especially at the extremities. Coupling of the new 3D imaging to existing navigation systems is possible. C-arm-CT will support the further development and implementation of open and minimally invasive surgical procedures.     

Low-artifact intravascular devices: MR imaging evaluation

Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible.     

HPLC柱切换法对炔诺酮α,β-聚(3-羟丙基)-DL-天冬酰胺在兔体内释放炔诺酮的测定

以柱切换HPLC(CSHPLC)技术,对炔诺酮α,β-聚(3-羟丙基)-DL-天冬酰胺在家兔体内释放液中炔诺酮的血药浓度进行了测定,以自制ODS预柱,水为流动相联机净化、富集样品;以Shim-packCLC-ODS为分析柱,甲醇-水(7:3)为流动相。结果表明CSHPLC对炔诺酮血药浓度有良好的选择性,回收率为82.6%(n=5),日内和日间精密度(RSD)分别小于4%和6%。在血清0.22～1.10μg/m1范围内炔诺酮色谱峰面积与浓度有较好的线性关系(n=5,r=0.998).     

Damage control orthopaedics in polytraumatized patients- current concepts

The principles of fracture management in patients with multiple injuries continue to be of crucial importance. Early treatment of unstable polytraumatized patients with head, chest, abdomen or pelvic injuries, with blood loss followed by immediate fracture fixation (Early Total Care -ETC) may be associated with secondary life threatening posttraumatic systemic inflammatory response syndrome (SIRS). Development of SIRS is typically a function of the type and severity of the initial injury (the “first hit”). Immediate Fracture fixation, using reamed nails or plates, in such unstable patients with multiple injuries is subsequently defined as the “second hit” and may be associated with development of acute respiratory distress syndrome (ARDS) and multiple organ failure (MOF), with relatively high morbidity and mortality.The other alternative for long bone fracture fixation in unstable polytraumatized patients is based on immediate treatment of life threatening conditions related to the injuries, followed by the initial use of minimally invasive modular external frames for long bone fractures and is called Damage Control Orthopedics (DCO) and is widely accepted. In order to refine the DCO concept and to avoid an overuse of external fixation, the “Safe Definitive Surgery” (SDS) concept has been introduced, which is a dynamic synthesis of both strategies (ETC and DCO). The SDS strategy employs clinical parameters and includes repeated assessment of patients. The following paper is going to summarize historical backgrounds and recent concepts in treatment of polytraumatized patients.     

Findings from an outbreak of carbapenem-resistant <Emphasis Type="Italic">Klebsiella pneumoniae</Emphasis> emphasize the role of antibiotic treatment for cross transmission

Purpose

In January 2015, we noticed by rectal swab analyses that seven of 23 patients at an early rehabilitation ward had been colonized with carbapenem-resistant Klebsiella pneumoniae (CKP). Here, we describe risk factors for CKP acquisition.

Methods

In the present study, the outbreak is described and risk factors for CKP acquisition are examined, e.g., antibiotic treatment. Microbiological analyses including corresponding results were examined to study when colonization with CKP occurred and whether patients had suffered from diarrhea. To examine whether spread of bacteria was clonal, multi-locus sequence typing as well as Xbal macrorestriction and pulsed-field gel electrophoresis was performed. The presence of carbapenmase was examined by PCR analysis. Through univariate analysis of risk factors in the small study sample, the role of antibiotic consumption, isolation procedures, patient’s age, gender, and Barthel index on colonization was elucidated.

Results

Clonal spread of the novel sequence type (ST)2255 was identified. Additionally, one patient was colonized with Escherichia coli and Serratia marcescens, both resistant to carbapenems, while a further patient carried another carbapenem-resistant E. coli strain. In all isolates, carbapenemase gene bla _OXA-48 was found to be located on a conjugative plasmid (60 kb), suggesting in vivo transmission from CKP to E. coli and S. marcescens. Univariate tests indicated that antibiotic treatment was the only risk factor showing a significant association with being colonized by CKP. In addition, the likelihood of diarrhea appeared to be higher in this group. Antibiotic treatment was associated with CKP colonization, whereas patients´ age, gender, Barthel index at admission, and residence with a CKP-colonized roommate were not. Diarrhea also seemed to support to distribution of CKP.

Conclusions

In this small outbreak, antibiotic treatment seemed to be the predominant risk factor for monoclonal transmission of bla _OXA-48 positive CKP.

     

Autologous adult rodent neural progenitor cell transplantation represents a feasible strategy to promote structural repair in the chronically injured spinal cord

Adult neural progenitor cells (NPCs) represent an attractive source for cell-based regenerative strategies in CNS disease. In animal models of spinal cord injury, syngenic adult NPCs, which were isolated from pooled post-mortem CNS tissue and co-transplanted together with fibroblasts, have been shown to promote substantial structural repair. The autologous transplantation of adult NPCs represents a major advantage compared with other sources of neural stem/progenitor cells. However, the feasibility of autologous NPC generation from a single biopsy in a relevant preclinical CNS disease model has yet to be demonstrated. To investigate this matter, adult Wistar rats underwent a cervical spinal cord lesion, which was followed by a minimal subventricular zone aspiration biopsy 2 days later. NPCs were isolated and propagated separately for each animal for the following 8 weeks. Thereafter, they were co-transplanted with simultaneously harvested skin fibroblasts in an autologous fashion into the cervical spinal cord lesion site. A total of 4 weeks later, graft survival, tissue replacement and axonal regeneration were assessed histologically. Animals receiving either allogenic NPCs combined with fibroblasts or autologous pure fibroblast grafts served as control groups. Within 8 weeks after the biopsy more than 3 million NPCs could be generated from a single aspiration biopsy, which displayed a differentiation pattern indistinguishable from syngenic NPC grafts. NPCs within autologous co-grafts readily survived, replaced cystic lesion defects completely and differentiated exclusively into glial phenotypes, thus paralleling previous findings with syngenic NPCs. The delayed transplantation 8 weeks after the spinal cord lesion elicited substantial axonal regeneration. These findings demonstrate that the therapeutic strategy to induce structural repair by transplanting adult autologous NPCs, after the successful propagation from a small brain biopsy into an acute CNS disease model, such as spinal cord injury, is feasible at the preclinical level.     

Preoperative Management of Endocrine,Hormonal, and Urologic Medications: Society for Perioperative Assessment and Quality Improvement (SPAQI) Consensus Statement

Perioperative medical management is challenging due to the rising complexity of patients presenting for surgical procedures. A key part of preoperative optimization is appropriate management of long-term medications, yet guidelines and consensus statements for perioperative medication management are lacking. Available resources utilize the recommendations derived from individual studies and do not include a multidisciplinary focus or formal consensus. The Society for Perioperative Assessment and Quality Improvement (SPAQI) identified a lack of authoritative clinical guidance as an opportunity to utilize its multidisciplinary membership to improve evidence-based perioperative care. SPAQI seeks to provide guidance on perioperative medication management that synthesizes available literature with expert consensus. The aim of this Consensus Statement is to provide practical guidance on the preoperative management of endocrine, hormonal, and urologic medications. A panel of experts with anesthesiology, perioperative medicine, hospital medicine, general internal medicine, and medical specialty experience was drawn together and identified the common medications in each of these categories. The authors then utilized a modified Delphi approach to critically review the literature and generate consensus recommendations.     

From the Cover: Brain signatures of artificial language processing: Evidence challenging the critical period hypothesis

Adult second language learning seems to be more difficult and less efficient than first language acquisition during childhood. By using event-related brain potentials, we show that adults who learned a miniature artificial language display a similar real-time pattern of brain activation when processing this language as native speakers do when processing natural languages. Participants trained in the artificial language showed two event-related brain potential components taken to reflect early automatic and late controlled syntactic processes, whereas untrained participants did not. This result challenges the common view that late second language learners process language in a principally different way from native speakers. Our findings demonstrate that a small system of grammatical rules can be syntactically instantiated by the adult speaker in a way that strongly resembles native-speaker sentence processing.