Extensive preoperative workup in diffuse esophageal leiomyomatosis associated with Alport syndrome influences surgical treatment: A case report

Introduction: Diffuse esophageal leiomyomatosis is a rare disease. Misdiagnosis is frequent and previous surgeries can complicate surgical management. The only treatment described for severe symptomatic cases is esophagectomy. Presentation of case: We describe a case of diffuse esophageal leiomyomatosis associated with Alport syndrome in a 21 year-old female where endoscopic ultrasonography (EUS) with concomitant fluoroscopy and 3D-gastric computed tomography (3D-GCT) modified surgical management. Discussion: The diagnosis of diffuse esophageal leiomyomatosis is difficult but can be greatly facilitated by extensive endoscopic and radiologic workup. Esophagectomy should only be entertained after complete anatomic mapping of the lesions, especially after previous surgeries. Conclusion: EUS and 3D-GCT should strongly be considered as part of routine preoperative workup in these patients

Chemical composition and electronic structure of the passive layer formed on stainless steels in a glucose-oxidase solution

International audienc

The influence of biosurfactant adsorption on the physicochemical behaviour of carbon steel surfaces using contact angle measurements and X-ray photoelectron spectroscopy

International audienceWe investigated modifications to carbon steel surfaces due to the adsorption of a biosurfactant derived from Pseudomonas fluorescens bacteria cells using contact angle measurements (CAM) and X-ray photoelectron spectroscopy (XPS). After conditioning carbon steel in solutions with three different concentrations of biosurfactant molecules: 0.05, 0.3 and 1 g.L−1, the average thickness of the biosurfactant layer on the carbon steel specimens was 7.9 ± 0.3, 12.1 ± 0.5 and 16.4 ± 0.7 Å, respectively. The biosurfactants changed the composition of both the Fe2+ and Fe3+ mixed-oxide layer and the outer layer, mostly composed of Fe3+ associated with magnetite. Contact angle measurements indicate decreased hydrophobic properties after the carbon steel was modified by biosurfactant. It was shown that the carbon steel surface free energy depends on the biosurfactant concentration, due to an acquisition of strong electron-donating propertie

Influence of Zn and Mg Alloying on the Corrosion Resistance Properties of Al Coating Applied by Arc Thermal Spray Process in Simulated Weather Solution

In this study, Al–Zn and Al–Mg coatings were deposited on steel substrates by an arc thermal spray process. X-ray diffraction and scanning electr on microscopy were used to characterize the deposited coatings and corrosion products. Open circuit potential (OCP), electrochemical impedance spectroscopy, and potentiodynamic studies were used to assess the corrosion characteristics of these coatings after exposure according to the Society of Automotive Engineers (SAE) J2334 solution of varying durations. This solution simulates an industrial environment and contains chloride and carbonate ions that induce corrosion of the deposited coatings. However, the Al–Mg alloy coating maintained an OCP of approximately - 0.911 V versus Ag/AgCl in the SAE J2334 solution even after 792 h of exposure. This indicates that it protects the steel sacrificially, whereas the Al–Zn coating provides only barrier-type protection through the deposition of corrosion products. The Al–Mg coating acts as a self-healing coating and provides protection by forming Mg 6 Al 2 (OH) 16 CO 3 (Al–Mg layered double hydroxides). Mg 6 Al 2 (OH) 16 CO 3 has interlocking characteristics with a morphology of plate-like nanostructures and an ion-exchange ability that can improve the corrosion resistance properties of the coating. The presence of Zn in the corrosion products of the Al–Zn coating allows dissolution, but, at the same time, Zn 5 (OH) 6 (CO 3 ) 2 and Zn 6 Al 2 (OH) 16 CO 3 are formed and act to reduce the corrosion rate

Age and depositional environment of the Draa Sfar massive sulfide deposit, Morocco

The Draa Sfar mineralization consists of two main stratabound orebodies, Sidi M’Barek and Tazacourt, located north and south of the Tensift River (“Oued Tessift”), respectively. Each orebody is comprised by at least two massive sulfide lenses. The hosting rocks are predominantly black shales, although minor rhyolitic rocks are also present in the footwall to the southern orebody. Shales, rhyolitic volcanic rocks, and massive sulfides are all included into the Sarhlef Series, which is recognized as one of the main stratigraphic units of the Moroccan Variscan Meseta. Hydrothermal activity related with an anomalous thermal gradient, together with a high sedimentation rate in a tectonically driven pull-apart marine basin, favored the accumulation of organic-rich mud in the deepest parts of the basin and the sedimentary environment suitable for massive sulfide deposition and preservation. This took place by replacement of the hosting unlithified wet mud below the sediment–water interface. Geochemical data suggest a sedimentary environment characterized by oxic water column and anoxic sediment pile with the redox boundary below the sediment–water interface. The low oxygen availability within the sediment pile inhibited oxidation and pyritization of pyrrhotite. Biostratigraphic analysis, based on the palynological content of the hosting black shales, restricts the age of the sulfides to the Asbian substage (mid-Mississippian). This age is consistent with earlier geochronological constraints

Predictive Factors and Risk Model for Positive Circumferential Resection Margin Rate after Transanal Total Mesorectal Excision in 2653 Patients with Rectal Cancer

The aim of this study was to determine the incidence of, and preoperative risk factors for, positive circumferential resection margin (CRM) after transanal total mesorectal excision (TaTME). Background: TaTME has the potential to further reduce the rate of positive CRM for patients with low rectal cancer, thereby improving oncological outcome. Methods: A prospective registry-based study including all cases recorded on the international TaTME registry between July 2014 and January 2018 was performed. Endpoints were the incidence of, and predictive factors for, positive CRM. Univariate and multivariate logistic regressions were performed, and factors for positive CRM were then assessed by formulating a predictive model. Results: In total, 2653 patients undergoing TaTME for rectal cancer were included. The incidence of positive CRM was 107 (4.0%). In multivariate logistic regression analysis, a positive CRM after TaTME was significantly associated with tumors located up to 1 cm from the anorectal junction, anterior tumors, cT4 tumors, extra-mural venous invasion (EMVI), and threatened or involved CRM on baseline MRI (odds ratios 2.09, 1.66, 1.93, 1.94, and 1.72, respectively). The predictive model showed adequate discrimination (area under the receiver-operating characteristic curve >0.70), and predicted a 28% risk of positive CRM if all risk factors were present. Conclusion: Five preoperative tumor-related characteristics had an adverse effect on CRM involvement after TaTME. The predicted risk of positive CRM after TaTME for a specific patient can be calculated preoperatively with the proposed model and may help guide patient selection for optimal treatment and enhance a tailored treatment approach to further optimize oncological outcomes

Carbon Dioxide Embolism Associated with Transanal Total Mesorectal Excision Surgery: A Report From the International Registries

BACKGROUND: Carbon dioxide embolus has been reported as a rare but clinically important risk associated with transanal total mesorectal excision surgery. To date, there exists limited data describing the incidence, risk factors, and management of carbon dioxide embolus in transanal total mesorectal excision. OBJECTIVE: This study aimed to obtain data from the transanal total mesorectal excision registries to identify trends and potential risk factors for carbon dioxide embolus specific to this surgical technique. DESIGN: Contributors to both the LOREC and OSTRiCh transanal total mesorectal excision registries were invited to report their incidence of carbon dioxide embolus. Case report forms were collected detailing the patient-specific and technical factors of each event. SETTINGS: The study was conducted at the collaborating centers from the international transanal total mesorectal excision registries. MAIN OUTCOME MEASURES: Characteristics and outcomes of patients with carbon dioxide embolus associated with transanal mesorectal excision were measured. RESULTS: Twenty-five cases were reported. The incidence of carbon dioxide embolus during transanal total mesorectal excision is estimated to be 480.4% (25/6375 cases). A fall in end tidal carbon dioxide was noted as the initial feature in 22 cases, with 13 (52%) developing signs of hemodynamic compromise. All of the events occurred in the transanal component of dissection, with mean (range) insufflation pressures of 15mm Hg (12\u201320mm Hg). Patients were predominantly (68%) in a Trendelenburg position, between 30\ub0 and 45\ub0. Venous bleeding was reported in 20 cases at the time of carbon dioxide embolus, with periprostatic veins documented as the most common site (40%). After carbon dioxide embolus, 84% of cases were completed after hemodynamic stabilization. Two patients required cardiopulmonary resuscitation because of cardiovascular collapse. There were no deaths. LIMITATIONS: This is a retrospective study surveying reported outcomes by surgeons and anesthetists. CONCLUSIONS: Surgeons undertaking transanal total mesorectal excision must be aware of the possibility of carbon dioxide embolus and its potential risk factors, including venous bleeding (wrong plane surgery), high insufflation pressures, and patient positioning. Prompt recognition and management can limit the clinical impact of such events. See Video Abstract at http://links. lww.com/DCR/A961