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We report on transport characteristics of field effect two-dimensional electron gases (2DEGs) in 24 nm wide indium arsenide surface quantum wells. High quality single-subband magnetotransport with clear quantized integer quantum Hall plateaus is observed to filling factor ν = 2 in magnetic fields of up to B = 18 T, at electron densities up to 8 × 10 11 /cm2. Peak mobility is 11 000 cm2/Vs at 2 × 10 12 /cm2. Large Rashba spin–orbit coefficients up to 124 meV Å are obtained through weak anti-localization measurements. Proximitized superconductivity is demonstrated in Nb-based superconductor-normal-superconductor (SNS) junctions, yielding 78%–99% interface transparencies from superconducting contacts fabricated ex situ (post-growth), using two commonly used experimental techniques for measuring transparencies. These transparencies are on a par with those reported for epitaxially grown superconductors. These SNS junctions show characteristic voltages I c R n up to 870 μV and critical current densities up to 9.6 μA/μm, among the largest values reported for Nb-InAs SNS devices. [ABSTRACT FROM AUTHOR]

Crimean-Congo hemorrhagic fever virus (CCHFV; family Nairoviridae) is a tick-borne pathogen that frequently causes lethal disease in humans. CCHFV has a wide geographic distribution, and cases have been reported in Africa, Asia, the Middle East, and Europe. Availability of a safe and efficacious vaccine is critical for restricting outbreaks and preventing disease in endemic countries. We previously developed a virus-like replicon particle (VRP) vaccine that provides complete protection against homologous and heterologous lethal CCHFV challenge in mice after a single dose. However, the immune responses induced by this vaccine are not well characterized, and correlates of protection remain unknown. Here we comprehensively characterized the kinetics of cell-mediated and humoral immune responses in VRP-vaccinated mice, and demonstrate that they predominantly target the nucleoprotein (NP). NP antibodies are not associated with protection through neutralizing activity, but VRP vaccination results in NP antibodies possessing Fc-mediated antibody effector functions, such as complement activation (ADCD) and antibody-mediated cellular phagocytosis (ADCP). This suggests that Fc-mediated effector functions may contribute to this vaccine'sefficacy. [ABSTRACT FROM AUTHOR]

We report on transport characteristics of field effect two-dimensional electron gases (2DEGs) in surface indium antimonide quantum wells. The topmost 5 nm of the 30 nm wide quantum well is doped and shown to promote the formation of reliable, low resistance Ohmic contacts to surface InSb 2DEGs. High quality single-subband magnetotransport with clear quantized integer quantum Hall plateaus is observed to filling factor ν = 1 in magnetic fields of up to B = 18 T. We show that the electron density is gate-tunable, reproducible, and stable from pinch-off to 4 × 10 11 cm−2, and peak mobilities exceed 24 000 cm2/V s. Large Rashba spin–orbit coefficients up to 110 meV · Å are obtained through weak anti-localization measurements. An effective mass of 0.019me is determined from temperature-dependent magnetoresistance measurements, and a g-factor of 41 at a density of 3.6 × 10 11 cm−2 is obtained from coincidence measurements in tilted magnetic fields. By comparing two heterostructures with and without a delta-doped layer beneath the quantum well, we find that the carrier density is stable with time when doping in the ternary Al0.1In0.9Sb barrier is not present. Finally, the effect of modulation doping on structural asymmetry between the two heterostructures is characterized. [ABSTRACT FROM AUTHOR]

Résumé L’abcès cérébral à Nocardia est plus fréquent chez les sujets immunodéprimés. Ici, nous rapportons le cas d’une nocardiose cérébrale et pulmonaire simulant une métastase tumorale survenue chez un patient algérien âgé de 40 ans apparemment immunocompétent. Le patient présentait des abcès intracérébraux révélés par l’imagerie par résonance magnétique suite à une crise d’épilepsie généralisée inaugurale. Il était apyrétique et a présenté une complication neurologique à type d’hémiparésie gauche. L’imagerie pulmonaire réalisée dans le cadre d’un bilan d’extension d’une néoplasie cérébrale a décelé la présence d’un nodule pulmonaire dans le segment apical du lobe inférieur droit. La craniotomie et la culture du pus cérébral extrait ont permis d’isoler et d’identifier Nocardia abscessus. Le patient a reçu initialement une bithérapie à base de cotrimoxazole et d’amikacine, puis un relais par cotrimoxazole seul. Après sept mois, l’évolution clinique était satisfaisante avec amélioration de l’hémiparésie. Les lésions intracrâniennes ont nettement régressé et le nodule pulmonaire a disparu. Le cotrimoxazole a été arrêté après douze mois de traitement. Après un recul de deux ans, l’état de santé de notre patient s’est nettement amélioré. Il est cependant suivi régulièrement en ambulatoire pour des examens de contrôle. Abstract Nocardial brain abscess is often occurring in immunocompromised patients. It is uncommon in immunocompetent individuals. Here, the authors describe a case of cerebral and pulmonary nocardiosis mimicking a metastatic tumor in an apparently health 40-year-old Algerian male. The patient presented multiple brain abscess revealed by inaugural epileptic seizure. He was afebrile and presented with left hemiparesis. Staging imaging showed a nodular lung lesion in the apical segment of the right lower lobe. The patient underwent double craniotomy for resection of the lesion. Culture of the resected specimen isolated Nocardia abscessus. The patient was initially started on intravenous trimethoprim-sulfamethoxazole and intravenous amikacine. He was switched to oral trimethoprim-sulfamethoxazole. He finished seven months of antibiotic therapy with a good clinical response. Imaging revealed reduction in the brain abscess and a complete resolution of the lung lesion. Cotrimoxazole was stopped after twelve months of therapy. After two years, the health status of our patient improves day after day. He is however regularly under medical supervision for control exams. [ABSTRACT FROM AUTHOR]

This study aims at genetic characterization and phylogenetic relationships of Nocardia brasiliensis focusing by using housekeeping rrs, hsp65, and sodA genes. N. brasiliensis is the species responsible for 80% of cases of actinomycetoma, one form of cutaneous nocardiosis which occurs mainly in tropical regions reaching immunocompetent patients in which the disease can lead to amputation. We analyze 36 indigenous cases of N. brasiliensis that happened in France. Phylogenetic analysis targeting rrs gene showed no robustness at phylogenetic nodes level. However, the use of a concatenation of hsp65 and sodA genes showed that the tested strains surprisingly ranked in 3 well-defined genotypes. Genotypes 2 and 3 were phylogenetically closer to each other and both diverged from genotype 1 sustained by a high bootstrap of 81%. This last genotype hosts all the cases of pulmonary forms (3), the sole cerebral form, and almost all the cases of immunocompromised patients (3 out of 4). Moreover, excepting one of them, all the strains belonging to this group present a susceptibility to imipenem which is not the case in the other genotypes that rarely count among them strains being susceptible to this drug. The haplotype diversity (Hd) of hsp65 (0.927) and sodA (0.885) genes was higher than that of rrs (0.824). For this gene, we obtained 16 polymorphic sites whereas, for hsp65 and sodA genes, up to 27 and 29 were identified, respectively. This study reveals that these two genes have an important genetic discriminatory power for the evaluation of the intraspecies genetic variability of N. brasiliensis and they may be useful for identification purposes at species level. This study also reveals the possible existence of a new species harbored by genotype 1. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Chemical Engineering is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Several studies have shown that bone morphogenetic proteins (BMPs) can influence adipogenic and osteogenic cell lineages. We have shown that a peptide derived from BMP-9 (pBMP-9) at 400 ng/ml inhibits the proliferation of preosteoblasts and induces differentiation. We have now determined the effects of pBMP-9 (400 ng/ml) and equimolar concentrations of BMP-2 (100 ng/ml), BMP-9 (84.6 ng/ml) and pBMP-9 (9.04 ng/ml) on human white preadipocytes (HWP). pBMP-9 dose dependently reduced the proliferation of HWP without affecting the number of apoptotic cells. Incubation of the cells for 1 h with BMP-2, BMP-9 or pBMP-9 activated the Smad1/5/8 pathway, while incubation for 7 days in adipocyte differentiation (AD) serum-free medium containing ciglitazone and equimolar concentrations of BMP-2, BMP-9 or pBMP-9 enhanced the levels of mRNA of the adipogenic markers aP2 and adipoQ and increased the number of lipid vesicles. Thus, pBMP-9, like BMP-9, can increase the AD of HWP in AD serum-free medium. [ABSTRACT FROM AUTHOR]

In the last few years, regulations for biomolecule production, and especially for extraction and purification of animal molecules such as collagen, have been reinforced to ensure the sanitary safety of the materials. To be authorized to market biomaterials based on collagen, manufacturers now have to prove that at least one step of their process is described in guidelines to inactivate prion, viruses, and bacteria. The present study focuses on the inactivation step performed during the extraction and purification of porcine type I atelocollagen. We chose to determine the reduction factor of a 1 M NaOH step on porcine parvovirus and four bacterial strains inactivation. During the extraction step, we deliberately inoculated the collagen suspension with the different microorganisms tested. Then, 1 M NaOH was added to the suspension for 1 hour at 20°C. We demonstrated that this treatment totally inactivated S. aureus, P. aeruginosa, C. albicans and A. niger which are bacterial strains responsible of severe human pathology. The reduction factors reached more than 4 logs for B. cereus spores and 4 logs for the porcine parvovirus. are encouraging as those two microorganisms are known to be very resistant to inactivation. [ABSTRACT FROM AUTHOR]

Summary: Biofilms develop inside endoscope channels even when valid endoscope reprocessing protocols are applied. The use of an efficient biocide is not sufficient if the channels are not cleaned thoroughly prior to disinfection. This study compared new anti-biofilm combinations of detachment promoting agents with a cleaning product in current use. Tests were performed using Teflon tubing and a contamination device that reproduces conditions that are prevalent during endoscopy. Products were subjected to static+brushing or dynamic treatments, and their ability to remove a preformed biofilm was assessed. The residual biofilm after treatment was assessed and compared with untreated controls. The percentage of surface covered by biofilm was measured after staining with crystal violet. Culturable bacteria levels were determined by plating the bacteria scraped from the tubing surface and counting the colony-forming units (CFU). Further tests were performed on actual endoscopes that had been contaminated artificially. Biofilm removal was confirmed by scanning electron microscopy. This study showed that the new anti-biofilm products prevented the build-up of biofilm and removed a mature biofilm (approximately 108 CFU/cm2), whereas protocols based on detergent-disinfectants containing quaternary ammonium compounds showed low efficacy as these protocols and products fixed the biofilm on the endoscope surfaces. The new procedure and agents represent a new approach to biofilm control that may improve the efficacy of endoscope reprocessing, and reduce the risk of transmitting infections. [Copyright &y& Elsevier]

Background: Observation and repeated examination may lead to favourable clinical outcomes in the ever-challenging diagnosis of appendicitis. The goal of this study was to evaluate clinical performance in the diagnosis of suspected appendicitis in a centre with limited access to medical imaging technologies and to identify factors associated with complicated cases.Methods: A retrospective review of the medical records of 211 consecutive surgical cases of suspected appendicitis, spanning an 11-year period, was performed. The delays before treatment and the subsequent patient outcomes were evaluated.Results: There were 8.1% of cases with negative findings on appendectomy, 75.8% with uncomplicated appendicitis, 12.3% with complicated appendicitis and 3.8% with other surgical conditions. The delay before the first medical consultation was significantly longer in patients with complicated appendicitis. The various delays after the first medical consultation did not differ significantly between the groups.Conclusions: In the context of limited available medical imaging modalities, clinical observation was not associated with an increased incidence of complicated appendicitis. The presence of complicated appendicitis was associated with the delay before the patient's first medical consultation. Clinical judgment can be prioritized and can lead to good clinical performance in the management of patients with suspected appendicitis, with no significant increase in rates of complicated appendicitis and negative findings on appendectomy. [ABSTRACT FROM AUTHOR]

BACKGROUND: Length of hospitalization is a good indicator of resource utilization. Older patients are increasingly suffering trauma, and comorbid medical conditions are also increasing. Our objective was to determine the separate and combined effect of these 2 factors on length of hospital stay for trauma patients in a tertiary trauma centre. METHODS: All 994 consecutive trauma patients surviving to hospital discharge between Apr. 1, 2000, and Mar. 31, 2001, were identified. Patient characteristics, injury severity and length of hospitalization were obtained from the hospital trauma registry. Each medical record was then reviewed for completeness of information and assessment of comorbid conditions. A multivariate linear regression model was developed to predict logarithmic length of stay from age and presence of a cormorbid condition while adjusting for the Injury Severity Score (ISS). RESULTS: The mean age of the patients was 49.7 (range from 14-100) years and median ISS was 9 (range from 1-50). At least 1 comorbid condition was present in 321 (32%) patients. Mean length of hospital stay was 15.3 days. The proportion of patients with a comorbid condition increased steadily with age, from 8.7% before the age of 55 years to 92% at 85 or more years of age (p < 0.001). According to the multivariate model, the presence of comorbidity, age and ISS were all independent predictors of hospital stay (p < 0.001). When applied to patients with the mean ISS value of 9, the model showed an increase in length of hospitalization for patients with a comorbid condition over those without; (3.6 v. 13.1 d for patients < 55 and > or = 85 yr respectively). Length of hospital stay increased particularly with neurologic and pulmonary problems. CONCLUSIONS: Comorbidity and age were both independently significant predictors of length of hospitalization over and beyond that which is expected based on the severity of the injuries. With an aging population, this phenomenon should severely affect resource utilization in trauma centres in the near future. Researchers should take account of both age and comorbidity in order to compare trauma populations. [ABSTRACT FROM AUTHOR]

BACKGROUND: The frequency of penetrating trauma is low in Canada. Current recommendations for the care of patients with penetrating injuries originate from inner city trauma centres with a high volume of such injuries and may not apply to Canada. The purpose of this study was to review the incidence and treatment of penetrating thoracoabdominal injuries in the 4 tertiary trauma centres in Quebec. METHODS: We identified all patients with penetrating thoracic or abdominal injuries who were taken to any of the 4 tertiary trauma centres in the province of Quebec between Apr. 1, 1998, and Mar. 31, 2001. Patients who were dead on arrival were excluded. Only patients with an Abbreviated Injury Scale of 2 or greater for the thoracic or abdominal regions were included. RESULTS: In total, 245 patients meeting our inclusion criteria were identified. Of these 223 (91%) were male. The mean (and standard deviation) age was 33.8 (13.2) years; range 15-90 years. The median Injury Severity Score was 10 (range 4-75). Overall in-hospital mortality was 6.9%. There were 203 patients (82.8%) with thoracic injuries and 192 patients (78.4%) with abdominal injuries. Fifty (20.4%) of these patients had injuries to both regions. A thoracotomy was carried out in 48 (31.4%) of 153 patients who had injuries to the thorax, and the abdomen was explored in 133 (93.7%) of the 142 patients with abdominal injuries. The incidence of these injuries in the study period varied from 3 to 49 cases per centre. CONCLUSIONS: The annual incidence of penetrating thoracoabdominal injuries is extremely low in all 4 of Quebec's tertiary trauma centres, and the number of thoracoabdominal procedures is even lower. Such a low exposure may jeopardize education and clinical competence. We need to rethink our educational strategies both for residents and for continuing medical education. New approaches to training and maintenance of competence must be developed. [ABSTRACT FROM AUTHOR]

Introduction Les Nocardia sont des bactéries à Gram positif responsables de pathologies rares mais graves. Disposer de données microbiologiques précises (sensibilité aux antibiotiques et typage moléculaire d’espèce) sur un grand nombre de souches est indispensable afin de choisir le traitement probabiliste puis de l’adapter. Notre objectif principal était de décrire la sensibilité aux antibiotiques et l’épidémiologie moléculaire des Nocardia en France sur une large collection de souches. Notre objectif secondaire était d’étudier l’évolution au cours du temps de la résistance aux antibiotiques et de la proportion de chaque espèce et d’évaluer la répartition géographique des souches collectées. Matériels et méthodes Nous avons analysé rétrospectivement les données relatives aux souches de Nocardia isolées chez l’homme durant 6 ans (2010–2015). L’identification d’espèce était obtenue par amplification et séquençage d’un fragment de 600pb du gène codant pour l’ARNr 16S (pour toutes les souches) et le gène hsp65 (pour les complexes N . abscessus et N . transvalensis ). La sensibilité aux antibiotiques était évaluée par technique de diffusion des antibiotiques en disques sur gélose Mueller-Hinton ajustée en cations. Résultats Nous avons inclus 793 souches de Nocardia , principalement isolées au niveau pulmonaire (53,8 %) ou à partir de lésions cutanées ou sous-cutanées (19,7 %). Les principales espèces étaient N . farcinica (20,2 %), N . abscessus complexe (19,9 %), N . nova complexe (19,5 %) et N . cyriacigeorgica (12,9 %). La proportion de N . farcinica augmentait significativement au cours du temps. Le linézolid, l’amikacine, le triméthoprime-sulfaméthoxazole, la minocycline, et l’imipénem étaient les antibiotiques les plus souvent actifs in vitro avec respectivement 0 %, 2,9 %, 7 %, 9,4 %, 13,8 % et 19,5 % de souches non sensibles ; ces fréquences étaient stables au cours du temps. N . farcinica était souvent non sensible aux céphalosporines de 3 e génération (∼ 80 % des souches), mais seulement 5 % des N . cyriacigeorgica et des N . abscessus complexe n’étaient pas sensibles au céfotaxime et à la ceftriaxone. Une plus grande densité de souches était observée dans le Sud-Est de la France et dans les territoires d’Outre-Mer, par rapport au Nord de la France. Conclusion Dans cette première étude épidémiologique des souches de Nocardia isolées chez l’Homme en France, N . farcinica était la principale espèce identifiée et sa proportion augmentait au cours du temps. [ABSTRACT FROM AUTHOR]

Currently for bacterial identification and classification the rrs gene encoding 16S rRNA is used as a reference method for the analysis of strains of the genus Nocardia. However, it does not have enough polymorphism to differentiate them at the species level. This fact makes it necessary to search for molecular targets that can provide better identification. The sod A gene (encoding the enzyme superoxide dismutase) has had good results in identifying species of other Actinomycetes. In this study the sod A gene is proposed for the identification and differentiation at the species level of the genus Nocardia. We used 41 type species of various collections; a 386 bp fragment of the sod A gene was amplified and sequenced, and a phylogenetic analysis was performed comparing the genes rrs (1171 bp), hsp 65 (401 bp), sec A1 (494 bp), gyr B (1195 bp) and rpo B (401 bp). The sequences were aligned using the Clustal X program. Evolutionary trees according to the neighbour-joining method were created with the programs Phylo_win and MEGA 6. The specific variability of the sod A genus of the genus Nocardia was analysed. A high phylogenetic resolution, significant genetic variability, and specificity and reliability were observed for the differentiation of the isolates at the species level. The polymorphism observed in the sod A gene sequence contains variable regions that allow the discrimination of closely related Nocardia species. The clear specificity, despite its small size, proves to be of great advantage for use in taxonomic studies and clinical diagnosis of the genus Nocardia. [ABSTRACT FROM AUTHOR]

The regulation of the interferon type I (IFN-I) response has been shown to rely on posttranslational modification by ubiquitin (Ub) and Ub-like interferon-stimulated gene product 15 (ISG15) to stabilize, or activate, a variety of IFN-I signaling and downstream effector proteins. Unlike Ub, which is almost perfectly conserved among eukaryotes, ISG15 is highly divergent, even among mammals. Since zoonotic viruses rely on viral proteins to recognize, or cleave, ISG15 conjugates in order to evade, or suppress, innate immunity, the impact of ISG15 biodiversity on deISGylating proteases of the ovarian tumor family (vOTU) from nairoviruses was evaluated. The enzymatic activities of vOTUs originating from the Crimean-Congo hemorrhagic fever virus, Erve virus, and Nairobi sheep disease virus were tested against ISG15s from humans, mice, shrews, sheep, bats, and camels, which are mammalian species known to be infected by nairoviruses. This along with investigation of binding by isothermal titration calorimetry illustrated significant differences in the abilities of nairovirus deISGylases to accommodate certain species of ISG15. To investigate the molecular underpinnings of species preferences of these vOTUs, a structure was determined to 2.5 Å for a complex of Erve virus vOTU protease and a mouse ISG15 domain. This structure revealed the molecular basis of Erve virus vOTU's preference for ISG15 over Ub and the first structural insight into a nonhuman ISG15. This structure also revealed key interactions, or lack thereof, surrounding three amino acids that may drive a viral deISgylase to prefer an ISG15 from one species over that of another. [ABSTRACT FROM AUTHOR]

Abstract: In 2012, an unprecedented number of four distinct, partially overlapping filovirus-associated viral hemorrhagic fever outbreaks were detected in equatorial Africa. Analysis of complete virus genome sequences confirmed the reemergence of Sudan virus and Marburg virus in Uganda, and the first emergence of Bundibugyo virus in the Democratic Republic of the Congo. [Copyright &y& Elsevier]

Bacteria of the genus Gordonia are rarely involved in human infections. We report here the case of a 30-year-old man from Guinea Buissau with mycetoma of the foot. 16S DNA sequencing after surgical biopsy identified Gordonia westfalica. To our knowledge, this is the first report of human infection caused by G. westfalica. [ABSTRACT FROM AUTHOR]