A non-inferiority study comparing the ultrasound-guided parasacral with a novel greater ischiatic notch plane approach in canine cadavers

OBJECTIVE

To describe the gross and ultrasound anatomy of the parasacral region and an ultrasound-guided greater ischiatic notch (GIN) plane approach aimed at staining the lumbosacral trunk (LST) in canine cadavers. To evaluate if the ultrasound-guided GIN plane approach is non-inferior to the previously described ultrasound-guided parasacral approach at staining the LST.

STUDY DESIGN

Prospective, randomized, non-inferiority experimental anatomic study.

ANIMALS

A total of 17 (23.9 ± 5.2 kg) mesocephalic canine cadavers.

METHODS

Anatomic and echographic landmarks, and the feasibility of performing a GIN plane technique were evaluated using two canine cadavers. The remaining 15 cadavers had each hemipelvis randomly assigned to be administered either parasacral or GIN plane injection of 0.15 mL kg-1 dye solution. The parasacral region was dissected after injections to assess the staining of LST, cranial gluteal nerve, pararectal fossa and pelvic cavity. The stained LST were removed and processed for histological evaluation of intraneural injections. A one-sided z-test for non-inferiority (non-inferiority margin -14%) was used to statistically evaluate the success of the GIN plane versus the parasacral approach. Data were considered statistically significant when p < 0.05.

RESULTS

The GIN plane and parasacral approach stained the LST in 100% and 93.3% of the injections, respectively. The success rate difference between treatments was 6.7% [95% confidence interval, -0.6 to 19.0%; p < 0.001 for non-inferiority]. The GIN plane and parasacral injections stained the LST for 32.7 ± 16.8 mm and 43.1 ± 24.3 mm, respectively (p = 0.18). No evidence of intraneural injection was found.

CONCLUSIONS AND CLINICAL RELEVANCE

The ultrasound-guided GIN plane technique resulted in nerve staining that was non-inferior to the parasacral technique and may be considered an alternative to the parasacral approach to block the LST in dogs.

Evaluation of transpulmonary ultrasound dilution cardiac output in piglets: accuracy, precision and trending ability with room temperature injectate

OBJECTIVE

Transpulmonary ultrasound dilution (TPUD) is a minimally invasive technique to measure cardiac output (CO) using a 1 mL kg^-1 isotonic 37 °C saline injectate indicator. The objective was to evaluate the performance of TPUD using a room temperature saline injectate.

STUDY DESIGN

Prospective experimental trial.

ANIMALS

A total of seven anesthetized male Yorkshire piglets.

METHODS

Piglets aged 1 month and weighing 7.7-9.0 kg were anesthetized with detomidine-ketamine-hydromorphone-isoflurane and a pulmonary artery flow probe (PAFP) placed via a median sternotomy. The thoracic cavity remained open during measurement of CO by PAFP and TPUD. The TPUD indicators of 1 mL kg^-1 0.9% saline at 37 °C and 20 °C were compared during infusions of phenylephrine and dobutamine, blood withdrawal and replacement. Bias, limits of agreement (LoAs) and percentage error (PE) between each iteration of PAFP and TPUD were measured with Bland-Altman plots. Trending ability via concordance, angular bias and radial LoA were compared.

RESULTS

Bland-Altman plots showed negligible bias with varying LoAs. PEs of 22% and 38% were found for 37 °C and 20 °C saline injectates, respectively. In the four-quadrant plots, the concordance rate was 94% and 100% for measurements obtained with 37 °C and 20 °C saline injectates, respectively. Angular bias for both were < ±5 °, with radial LoA < ±7 °.

CONCLUSIONS

TPUD was accurate when using 1 mL kg^-1 of isotonic saline at 37 °C in a range of CO within 0.2-0.8 L minute^-1, and it reliably tracked positive and negative changes in CO. Room temperature (20 °C) indicator was less accurate but equally able to track direction of changes in CO.

CLINICAL RELEVANCE

The use of room temperature injectates allows an easy, readily available clinical application of TPUD CO monitoring while preserving the trending ability of the monitor.

The role of the posterior malleolus in the treatment of unstable upper ankle joint injuries - A biomechanical study

BACKGROUND

This biomechanical study aimed to test if the fixation of the posterior malleolus (PM) only with screws inserted from posterior to anterior (PA) restores stability comparable with the natural condition. The extent of stability was also compared with that of anterior to posterior (AP) screw osteosynthesis (OS) with an additional syndesmotic screw (SS).

METHODS

First, the stability of the upper ankle joint in seven pairs of intact lower legs were examined. Subsequently, half of the lower legs were treated with PA screw fixation of a PM fracture without SS and the other half with AP screw fixation with additional tricortical SS.

RESULTS

PA OS without SS showed significantly more diastasis (p = 0.027). The AP OS with an SS revealed a diastasis that was comparable with the intact condition (p = 0.797). The use of SS led to significantly higher stability compared to OS without SS (p = 0.019).

CONCLUSIONS

The Fixation of the PM alone without an additional syndesmotic screw cannot achieve intact upper ankle stability. Fixation of a PM fracture with an SS helps in nearly achieving the natural condition.

New capability for indirect neutron capture measurements: The DICER instrument at LANSCE

The Device for Indirect Capture on Radionuclides (DICER) implements a new indirect technique for (n,γ) studies in which the neutron capture rate is determined from analysis of resonance neutron transmission data. The DICER instrument and associated radionuclide production at the Isotope Production Facility (IPF), both at the Los Alamos Neutron Science Center (LANSCE), as well radioactive sample fabrication, have been under development in the last few years. First measurements on a radioactive sample (88Zr, t½=83.4 days), which was recently reported to have an extremely large thermal neutron capture cross section and resonance integral [1, 2], are planned for the winter of 2021. A performance overview, brief details on the 88Zr fabrication and proof of good operation results will be presented.

Novel modified endoscopic mucosal resection of large GI lesions (> 20 mm) using an external additional working channel (AWC) may improve R0 resection rate: initial clinical experience

Background

En-bloc resection of large, flat dysplastic mucosal lesions of the luminal GI tract can be challenging. In order to improve the efficacy of resection for lesions ≥2 cm and to optimize R0 resection rates of lesions suspected of harboring high-grade dysplasia or early adenocarcinoma, a novel grasp and snare EMR technique utilizing a novel over the scope additional accessory channel, termed EMR Plus (EMR+), was developed. The aim of this pilot study is to describe the early safety and efficacy data from the first in human clinical cases.

Methods

A novel external over-the-scope additional working channel (AWC) (Ovesco, Tuebingen, Germany) was utilized for the EMR+ procedure, allowing a second endoscopic device to be used through the AWC while using otherwise standard endoscopic equipment. The EMR+ technique allows tissue retraction and a degree of triangulation during endoscopic resection. We performed EMR+ procedure in 6 patients between 02/2018–12/2018 for lesions in the upper and lower GI tract.

Results

The EMR+ technique utilizing the AWC was performed successfully in 6 resection procedures of the upper and/or lower GI tract in 6 patients in 2 endoscopy centers. All resections were performed successfully with the EMR+ technique, all achieving an R0 resection. No severe adverse events occurred in any of the procedures.

Conclusions

The EMR+ technique, utilizing an additional working channel, had an acceptable safety and efficacy profile in this preliminary study demonstrating it’s first use in humans. This technique may allow an additional option to providers to remove complex, large mucosal-based lesions in the GI tract using standard endoscopic equipment and a novel AWC device.

Quantification of Wheat, Rye, and Barley Gluten in Oat and Oat Products by ELISA RIDASCREEN® Total Gluten: Collaborative Study, First Action 2018.15

Background: Since its introduction to the analytical community, the R5 method to quantify gluten led to a strong improvement of the situation for the food industry and celiac patients. During recent years, some questions arose on the use of the Codex Alimentarius factor of two to convert from prolamins to gluten, an overestimation of rye and barley, inadequate detection of glutelins, and the inhomogeneous distribution of gluten in oats. These limitations of the R5 method, especially when measuring oat samples, led to AOAC Standard Method Performance Requirement (SMPR®) 2017.021, which was approved by stakeholders in 2017. Objective: We present a collaborative study of a method for the quantitative analysis of wheat, rye, and barley gluten in oat and oat products using a sandwich ELISA that is based on four different monoclonal antibodies including the R5 monoclonal anitbody. Methods: The sandwich ELISA detects intact gliadins and related prolamins from rye and barley, high-molecular-weight (HMW) glutenin subunits (GS) from wheat, HMW secalins from rye, and low-molecular-weight (LMW) GS from wheat. It does not detect D-hordeins from barley. Samples are extracted by Cocktail solution, subsequently followed by 80% ethanol, and analyzed within 50 min. Results: The measurement range is between 5 and 80 mg/kg gluten using a calibrator made out of a gluten extract from four different wheat cultivars. The results of the collaborative test with 19 participating laboratories showed recoveries ranging from 99 to 137% for all three grain sources. Relative reproducibility SDs for samples &gt;10 mg/kg gluten ranged from 10 to 53%. Conclusions: The collaborative study results confirmed that the method is accurate and suitable to measure gluten from all three grain sources and has demonstrated performance on oat matrices, which meets the criteria as specified in SMPR 2017.021. Data from in-house validation experiments are available as Annex B to this publication.

Endoscopic submucosal dissection with a novel high viscosity injection solution (LiftUp) in an ex vivo model: a prospective randomized study

Introduction  Endoscopic submucosal dissection (ESD) is increasingly being used in the western world. Submucosal injectates are an essential tool for the ESD procedure. In this study, we evaluated a novel copolymer injectate (LiftUp, Ovesco, Tübingen Germany) in an established ESD model (EASIE-R) in comparison to existing submucosal injectables. Materials and methods  We conducted a prospective, randomized ex vivo study performing ESD with three injectates: LiftUp, hydroxyethyl starch (HAES 6 %) and normal saline solution (NaCl 0.9 %). A total of 60 artificial lesions, each 3 × 3 cm in size, were resected in an ex vivo porcine model, utilizing one of the three studied injectates (n = 20 ESDs per injectate). Study parameters were: en bloc resection rate, perforation rate, lifting property, time of injection, injectate volume, general ESD procedure time, and overall procedure time. Results  All 60 lesions were successfully resected using the standard ESD technique. LiftUp had no procedure related perforations, one perforation occurred in the HAES group, and two perforations in the NaCl group ( P  > 0.05). Furthermore, adequate lifting was achieved in 16/20 (80 %) using LiftUp, 6/20 (30 %) in the HAES group and 6/20 (30 %) in the NaCl group ( P  < 0.0002). En bloc resection was achieved in 19 (95 %) with LiftUp, in 20 (100 %) with HAES, and in 16 (80 %) with NaCl. General ESD procedure time and overall procedure time were not different among the three groups. Conclusion  LiftUp appears to be a safe alternative to established fluids for ESD. It had a significantly improved lifting effect and required significantly less injected volume compared to well-established lifting solutions.

Wheat-dependent exercise-induced anaphylaxis

Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a rare, but potentially severe food allergy exclusively occurring when wheat ingestion is accompanied by augmenting cofactors. It is clinically characterized by anaphylactic reactions ranging from urticaria and angioedema to dyspnoea, hypotension, collapse, and shock. WDEIA usually develops after ingestion of wheat products followed by physical exercise. Other cofactors are acetylsalicylic acid and other non-steroidal anti-inflammatory drugs, alcohol, and infections. The precise mechanisms of WDEIA remain unclear; exercise and other cofactors might increase gastrointestinal allergen permeability and osmolality, redistribute blood flow, or lower the threshold for IgE-mediated mast cell degranulation. Among wheat proteins, ω5-gliadin and high-molecular-weight glutenin subunits have been reported to be the major allergens. In some patients, WDEIA has been discussed to be caused by epicutaneous sensitization with hydrolysed wheat gluten included in cosmetics. Diagnosis is made based on the patient's history in combination with allergy skin testing, determination of wheat-specific IgE serum antibodies, basophil activation test, histamine release test, and/or exercise challenge test. Acute treatment includes application of adrenaline or antihistamines. The most reliable prophylaxis of WDEIA is a gluten-free diet. In less severe cases, a strict limitation of wheat ingestion before exercise and avoidance of other cofactors may be sufficient.

Neutron capture cross section of unstable 63Ni: implications for stellar nucleosynthesis

The 63Ni(n,γ) cross section has been measured for the first time at the neutron time-of-flight facility n_TOF at CERN from thermal neutron energies up to 200 keV. In total, capture kernels of 12 (new) resonances were determined. Maxwellian averaged cross sections were calculated for thermal energies from   kT=5-100  keV with uncertainties around 20%. Stellar model calculations for a 25M⊙ star show that the new data have a significant effect on the s-process production of 63Cu, 64Ni, and 64Zn in massive stars, allowing stronger constraints on the Cu yields from explosive nucleosynthesis in the subsequent supernova.

Comparative study of NOTES alone vs. EUS-guided NOTES procedures

BACKGROUND AND STUDY AIMS

Natural-orifice transluminal endoscopic surgery (NOTES) is in the developmental stage for various indications, but several obstacles remain to be overcome before NOTES procedures can come into routine clinical use. Of these obstacles, (1) transluminal injury due to exclusive use of endoluminal endoscopy to create the incision and (2) lack of orientation might be prevented by employing endoscopic ultrasound guidance. In this comparative study we assessed the role of endoscopic ultrasound guidance in various NOTES procedures.

METHODS

Three transesophageal (mediastinoscopy/thoracoscopy) or transgastric procedures (gastrojejunostomy, adrenal gland removal) were performed in pigs using NOTES alone or with endoscopic ultrasound guidance (EUS). In NOTES alone the study end point was three major complications, at which point EUS guidance was added for the same procedures up to the same number of cases. The primary outcome was the rate of major complications; secondary outcome parameters were all complications and technical success.

RESULTS

Forty-six pigs were included. Three major complications occurred in the first 24 NOTES-alone procedures: these were bleeding and organ injury, all during mediastinoscopy/thoracoscopy procedures. Adrenal gland removal failed in all procedures in which it was attempted, while gastrojejunostomy (n = 6) was performed successfully and without complications. In the next 22 animals EUS guidance enabled safe mediastinal access (n = 10) and adrenal gland removal (n = 6). For gastrojejunostomy, EUS guidance offered no additional benefit.

CONCLUSIONS

EUS guidance appears to be helpful in gaining access or identifying structures in anatomically difficult areas in NOTES procedures.

Which parameters might predict complications after natural orifice endoluminal surgery (NOTES)? Results from a randomized comparison with open surgical access in pigs

BACKGROUND AND STUDY AIMS

Natural orifice transluminal endoscopic surgery (NOTES) is currently developed and assessed mainly in pig experiments. The vast majority of studies show a good outcome in short-term follow-up. The current study aims at comparing various parameters of postinterventional assessment and surveillance in relation to clinical behavior and autopsy results to find suitable control parameters and also to assess the pig as suitable model for NOTES compared with open surgery.

METHODS

Within the framework of a randomized prospective study of 20 pigs with iatrogenic colonic perforation comparing endoscopic with open surgical closure, clinical examination, including observation of behavior, food intake, and body temperature, was carried out daily. Laboratory parameters (white blood cells [WBC], granulocytes) were measured in 14 animals. Weight was measured preoperatively and on days 2 and 7 postoperatively. Results were matched with complications found during/after 2 weeks' survival. Pre-autopsy sterile cultures were taken from the peritoneal cavities to determine possible bacterial contamination.

RESULTS

Three animals from the surgical group were sacrificed on days 4, 8, and 12 because they became severely ill, with autopsy revealing intussusception from adhesions, peritoneal abscess, and peritonitis, in one pig each; another animal had culture positive for ESCHERICHIA COLI. Three minor complications (2 cough, 1 continuing fever with adhesions to the bladder found on autopsy) occurred in the endoscopic group without compromised recovery. WBC were measured in 14 animals, and found to be elevated (8 - 36 x 10 (9)/l) in six on day 2 including the two animals with severe complications. Between pre- and post-procedure, WBC increased about twofold in the uneventful cases but fourfold in the two animals with severe complications. Cultures from the abdominal cavity before autopsy were negative in all but one animal.

CONCLUSION

Animal behavior was a reliable indicator of severe complications. Fever, body weight, and the results of in vitro cultures of the peritoneal fluid did not indicate complications. WBC proved not to be specific but showed a larger increase in pigs with severe complications.

Natural orifice transluminal endoscopic surgery (NOTES) in the mediastinum: long-term survival animal experiments in transesophageal access, including minor surgical procedures

BACKGROUND AND STUDY AIMS

Natural orifice transluminal endoscopic surgery (NOTES) within the peritoneal cavity is rapidly evolving, using transgastric, transcolonic, or transvaginal access. There is little experience with transesophageal NOTES access to the mediastinum. This prospective long-term animal survival study was performed to explore the feasibility and safety of transesophageal intrathoracic procedures including minor surgery.

MATERIAL AND METHODS

Nine pigs were used for acute (n = 2) and up to 6-week survival studies (n = 7), followed by autopsy and histological investigation. The esophageal incision site was chosen using EUS; this was followed by endoscopic mediastinoscopy and therapeutic procedures such as mediastinal lymph node removal, saline injection into myocardium, and pericardial fenestration. The wall was closed using a suturing system or endoscopic clips.

RESULTS

No acute complications were recorded with respect to mediastinal structures, pericardium, cardiac rhythm, or circulatory parameters. Removal of small mediastinal lymph nodes (n = 2) was feasible, but proved to be difficult. Other procedures, specifically at the heart were all successfully performed. Endoscopy after 4 - 6 weeks showed a well-healed esophageal incision. Autopsy with histology revealed no signs of mediastinitis, infection, bleeding, or pericarditis. The esophageal scar was found to be well healed in all cases, but with a muscular gap where clip closure had been used.

CONCLUSIONS

Transmural esophageal incision and endoscopic partial mediastinoscopy including therapeutic procedures on the heart or mediastinum proved feasible in long-term survival animal studies. Clip closure of the defect was effective, but did not close the esophageal muscle layer. Other means such as endoscopic suturing appear to be preferable.

Transesophageal endoscopic ultrasound-guided access to the heart

BACKGROUND AND STUDY AIMS

Endoscopic ultrasound and fine-needle aspiration of paramural lesions are established diagnostic techniques in gastroenterology and are now also used for therapeutic purposes. The proximity of the heart to the esophagus and the utility of the diagnostic technique of transesophageal echography prompted us to explore the possibilities of approaching the heart through the esophagus.

METHODS

In acute experiments (n = 2) and survival experiments (n = 6) on anesthetized pigs, the anatomical landmarks were first identified and studied, before introduction of the needle through the posterior cardiac wall into the left atrium, and then beyond, as far as the aortic valve. The smallest structure targeted was the coronary artery. The animals in the survival group were monitored clinically over a 2-week period and also underwent endoscopic and cardiologic re-examinations prior to autopsy. Three patients were also investigated using the technique.

RESULTS

No visible damage was observed in the heart in the two animals which were sacrificed immediately or in the six surviving pigs (except for one small hematoma). The needle could be introduced repeatedly into the left atrium, followed by the injection of saline. Reaching the aortic valve was more difficult because of the moving target, but ablation therapy was technically possible. The coronary artery was successfully punctured in three of the animals (all three weighed 40 kg or more); in smaller animals, the needle overshot the lumen of these minute arteries. Of the three patients investigated, pericardial fluid was successfully aspirated in two patients and a left atrial mass was punctured in the third patient (excluding neoplasia, the final diagnosis being thrombus).

CONCLUSION

These animal studies and clinical cases suggest that transesophageal intracardiac procedures could become feasible and that further exploration by gastroenterologists and cardiologists may be justified.

Beamline Performance Simulations for the Fundamental Neutron Physics Beamline at the Spallation Neutron Source

Monte Carlo simulations are being performed to design and characterize the neutron optics components for the two fundamental neutron physics beamlines at the Spallation Neutron Source. Optimization of the cold beamline includes characterization of the guides and benders, the neutron transmission through the 0.89 nm monochromator, and the expected performance of the four time-of-flight choppers. The locations and opening angles of the choppers have been studied using a simple spreadsheet-based analysis that was developed for other SNS chopper instruments. The spreadsheet parameters are then optimized using Monte Carlo techniques to obtain the results presented in this paper. Optimization of the 0.89 nm beamline includes characterizing the double crystal monochromator and the downstream guides. The simulations continue to be refined as components are ordered and their exact size and performance specifications are determined.

Neutron capture cross section measurement of 151Sm at the CERN neutron time of flight facility (n_TOF)

The151Sm(n,gamma)152Sm cross section has been measured at the spallation neutron facility n_TOF at CERN in the energy range from 1 eV to 1 MeV. The new facility combines excellent resolution in neutron time-of-flight, low repetition rates, and an unsurpassed instantaneous luminosity, resulting in rather favorable signal/background ratios. The 151Sm cross section is of importance for characterizing neutron capture nucleosynthesis in asymptotic giant branch stars. At a thermal energy of kT=30 keV the Maxwellian averaged cross section of this unstable isotope (t(1/2)=93 yr) was determined to be 3100+/-160 mb, significantly larger than theoretical predictions.

About medicine and the arts. Charcot and French literature at the fin-de-siècle

The relationship between medicine and the arts, literature in particular, has many aspects. One of the most obvious relations is the use of literature as a source for historical studies. Jean-Martin Charcot and his school often appear in French literature at the end of the 19th century. Several aspects will be highlighted in this study, including (1) the ideas about degenerative diseases in the work of Emile Zola, the main author of the naturalistic movement; (2) decadence and spiritism in two "transitional" novels by Joris Karl Huysmans, who, once supporter of the naturalistic movement, changed his ideas following observations of disease and cure that could not be explained in a scientific way. Charcot's work on hysteria and hypnosis, as well as Brown-Séquard's rejuvenation experiments with testicular extracts played an important role with this respect; (3) Charcot's relationship with the Daudets, in particular his treatment of Alphonse's tabes dorsalis and the ambivalent attitude of his son Léon Daudet towards Charcot; (4) the influence of the lectures at the Salpêtrière on the work of Guy de Maupassant, who attended the lessons in the mid-1880s. The reading of novels and biographies of these authors provides a part of the social context and the cultural atmosphere in Paris at the "fin-de-siècle" when Charcot and his school played an important role in medicine. Moreover, it shows the influence of medicine and science on society as recorded by writers.

Epidemiology of inclusion body myositis in the Netherlands: a nationwide study

Epidemiologic data on inclusion body myositis (IBM) are scarce, and possibly biased, because they are derived from larger neuromuscular centers. The present nationwide collaborative cross-sectional study, which culminated on July 1, 1999, resulted in identification of 76 patients with IBM and the establishment of a prevalence of 4.9 patients with IBM per million inhabitants in the Netherlands. Several discrepancies suggest that this may be an underestimation. The most frequently identified pitfall in diagnosing IBM was an erroneous diagnosis of polymyositis or motor neuron disease.