Innovative SALDI mass spectrometry analysis for Alzheimer's disease synthetic peptides detection.

Alzheimer's disease (AD) is nowadays the prominent cause of senile dementia. This pathology is characterized by aggregation of neurofibrillary tangles in cells and by the accumulation of amyloid plaques in the brain. Noteworthy, a phosphorylated protein (tau protein) and a peptide presenting two overlapping sequences of 40 or 42 residues named β-amyloid peptides 1-40 (Aβ 1-40) and 1-42 (Aβ 1-42), respectively, were related to such deleterious phenomena.

Analytical Tools for Dynamic Combinatorial Libraries of Cyclic Peptides.

Target-directed dynamic combinatorial chemistry is a very attractive strategy for the discovery of bioactive peptides. However, its application has not yet been demonstrated, presumably due to analytical challenges that arise from the diversity of a peptide library with combinatorial side-chains. We previously reported an efficient method to generate, under biocompatible conditions, large dynamic libraries of cyclic peptides grafted with amino acid's side-chains, by thiol-to-thioester exchanges.

[Pre-iliac tumor mass syndrome: An atypical rheumatoid nodule].

Rheumatoid arthritis (RA) is a polymorphous chronic inflammatory disease that is common in general population and is responsible for the occurrence of subcutaneous or visceral rheumatoid nodules. Their typical clinical presentations and localizations do not generally pose any diagnostic or therapeutic problem. We report here an atypical fistulized presentation of an unusual iliac rheumatoid nodule in a 65-year-old female patient.

Development of nanomaterial enabling highly sensitive surface-assisted laser desorption/ionization mass spectrometry peptide analysis.

Rationale: Surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) is an approach derived from matrix-assisted laser desorption/ionization (MALDI)-MS which overcomes the drawbacks associated with the use of organic matrices required to co-crystallize with the analytes. Indeed, nanomaterials commonly used in SALDI-MS as inert surfaces to promote desorption/ionization (D/I) ensure straightforward direct deposition of samples while providing mass spectra with ions only related to the compound of interest. The objective of this study was to develop a novel SALDI-MS approach based on steel plates that are surfaces very rapidly and easily tuned to perform the most efficient peptide detection as possible.

Methylmetacrylate (PMMA) cranioplasty technique: Technical interest of intraoperative modeling and review of the literature.

Reconstruction of bone loss in the cranial vault may be necessary for functional or aesthetic reasons following trauma, decompression craniectomy, or craniofacial malformations. Many techniques have been described in the literature, using various materials, each with its own advantages and drawbacks. Reconstruction with polymethylmetacrylate cement has the advantage of a durable result and relative ease of use.

Extracellular 20S proteasome secreted via microvesicles can degrade poorly folded proteins and inhibit Galectin-3 agglutination activity.

Proteasomes are major non-lysosomal proteolytic complexes localized in the cytoplasm and in the nucleus of eukaryotic cells. Strikingly, high levels of extracellular proteasome have also been evidenced in the plasma (p-proteasome) of patients with specific diseases. Here, we examined the process by which proteasomes are secreted, as well as their structural and functional features once in the extracellular space.

Dynamic Amino Acid Side-Chains Grafting on Folded Peptide Backbone.

An efficient strategy for the synthesis of large libraries of conformationally defined peptides is reported, using dynamic combinatorial chemistry as a tool to graft amino acid side chains on a well-ordered 3D (3-dimension) peptide backbone. Combining rationally designed scaffolds with combinatorial side chains selection represents an alternative method to access peptide libraries for structures that are not genetically encodable. This method would allow a breakthrough for the discovery of protein mimetic for unconventional targets for which little is known.

Burn injury and incidence of psychiatric disorders: A retrospective cohort study of 18,198 patients from Germany.

Aims: The goal of this study was to investigate the association between burn injury and the incidence of psychiatric disorders in patients followed for up to five years in general practices in Germany.

Methods: This study included patients receiving an initial diagnosis of burn injury in one of 1178 general practices in Germany between 2015 and 2018 (index date). Individuals without burn injury were matched (1:1) to those with burn injury by sex, age, index year, and general practice.

In-capillary (electrophoretic) digestion-reduction-separation: A smart tool for middle-up analysis of mAb.

Comprehensive characterization of physicochemical properties of monoclonal antibodies (mAbs) is a critical process to ensure their quality, efficacy, and safety. For this purpose, mAb analysis at different levels (bottom-up, middle-up) is a common approach that includes rather complex multistep sample preparation (reduction, digestion). To ensure high analysis performance, the development of fully integrated methodologies is highly valuable.

Fast in-line bottom-up analysis of monoclonal antibodies: Toward an electrophoretic fingerprinting approach.

For their characterization and quality control, monoclonal antibodies are frequently analyzed at the bottom-up level to generate specific fingerprints that can be used to tackle post-translational modifications or ensure production consistency between lots. To circumvent time-consuming and labor-intensive off-line sample preparation steps, the implementation of integrated methodologies from sample preparation to separation and detection is highly valuable. In this perspective, capillary zone electrophoresis appears as a choice technique since the capillary can subsequently be used as a vessel for sample preparation and electrophoretic discrimination/detection of the reaction products.

[Current place of cultured epithelial autografts in the management of massive burns and future prospects: Literature review].

Cultured Epithelial Autografts (CEAs), developed at the end of the 1970s from in vitro culture amplification of keratinocytes, have led to a therapeutic revolution in the treatment of major burns. The areas of improvement of the cultures initially involved the manufacturing processes (culture media, support matrices, etc.) and then clinical applications (use of a largely expanded allogeneic or autologous dermal bed).

Medical and surgical management of lower extremity war-related injuries. Experience of the French Military Health Service (FMHS).

Lower extremity war wounds are characterized by high-energy trauma occasioning loss of complex and pluritissular substances. The support pipeline put into place by the French defense health service (SSA) is designed to rapidly evacuate the injured person from the scene of injury to mainland France, following initial surgery in the framework of a sequential tactic known as "Damage Control Surgery". This strategy is aimed at stabilizing the traumatized individual and enabling his evacuation.

[The "racket-like" flap: Method to increase the reliability of the sural neuro-cutaneous flap].

We realized a retrospective study from 2003 to 2018 comparing two surgical techniques of neuro-fascio-cutaneous sural flap harvesting to improve their reliability: the "vascular pedicle tunneling" method and the "racket-like" flap method. There are 35 flaps in this series from lower distal limb reconstruction: 21 "racket-like" flaps and 14 "tunneling-pedicle" flaps. There were no partial or total necrosis case in the "racket-like" flaps group.

Perforator Mapping of the Superficial and Deep Inferior Epigastric Artery in the Abdominal Region of the Vietnamese.

Background: Previous studies worldwide have investigated the anatomy of the perforators of the deep inferior epigastric arteries to figure out the navigation patterns of the perforators on the abdominal wall. This has been inconsistent amongst the researchers about how to select the perforator to increase the blood supply area for the flap.

Aim: To explore the blood supply area of the perforators of the superficial and deep inferior epigastric artery in the abdominal region of the Vietnamese by dissection and 64-slice multislice computed tomography (64-slice MSCT).

An in-line enzymatic microreactor for the middle-up analysis of monoclonal antibodies by capillary electrophoresis.

Monoclonal antibodies (mAbs) are undergoing rapid growth in the pharmaceutical industry due to their clinical efficiency. Concomitantly, robust, cost-effective, and high throughput analytical methods are needed for their quality control. Among all analytical techniques, capillary electrophoresis (CE) presents alternative and attractive features because the capillary can be used both as a microreactor and as a support for separation.

Extensive septic myonecrosis related to compartment syndrome: is the upper extremity salvage achievable in precarious setting?

Management of acute compartment syndrome is well known and based on emergent and generous fasciotomies. In absence of such fasciotomies, or if they are performed too late, the compartment syndrome leads to a Volkmann's syndrome or to a dramatic septic myonecrosis raising the question of an amputation. However, salvage treatment of these extreme clinical presentations may be preferable at the upper extremity, particularly in developing countries where access to sophisticated prosthetic devices is limited.

Complex upper arm reconstruction using an antero-lateral thigh free flap after an extravasation of Yttrium-90-ibritumomab Tiuxetan: A case report and literature review.

Yttrium-90-Ibritumomab Tiuxetan (Zevalin) is used in the treatment of non- Hodgkin's lymphoma. Extravasation is an iatrogenic complication that is fortunately rare. However, the treatment of this complication is often complex due to the risk of extensive skin necrosis and unpredictable evolution of localized irradiation.

Mapping Dicorynia guianensis Amsh. wood constituents by submicron resolution cluster-TOF-SIMS imaging.

The preparation of tropical wood surface sections for time-of-flight secondary ion mass spectrometry imaging is described, and the use of delayed extraction of secondary ions and its interest for the analysis of vegetal surface are shown. The method has been applied to the study by time-of-flight secondary ion mass spectrometry imaging with a resolution of less than one micron of a tropical wood species, Dicorynia guianensis, which is one of the most exploited wood in French Guiana for its durable heartwood. The heartwood of this species exhibits an economical importance, but its production is not controlled in forestry.

Biomedical studies by TOF-SIMS imaging.

Imaging by secondary ion mass spectrometry coupled to time-of-flight mass analysis (TOF-SIMS) is a method of which the applications have greatly increased since 10 years. Taking advantage of the development of cluster ion sources, TOF-SIMS offers images of molecular ions at a micrometer lateral resolution or slightly below and does not require complex sample preparation. Although TOF-SIMS has been primarily dedicated to surface analysis of inorganic or polymeric samples, several groups have successfully demonstrated that TOF-SIMS imaging is also perfectly suited for mapping organic compounds, such as drugs or lipids, directly on tissue sections from animals or from human biopsies.

Low doses of arginine butyrate derivatives improve dystrophic phenotype and restore membrane integrity in DMD models.

A new approach to treating Duchenne muscular dystrophy was investigated by using the ester or amide covalent association of arginine [nitric oxide (NO) pathway] and butyrate [histone deacetylase (HDAC) inhibition] in mdx mice and patient myotubes. Two prodrugs were synthesized, and the beneficial effects on dystrophic phenotype were studied. Nerve excitability abnormalities detected in saline-treated mice were almost totally rescued in animals treated at low doses (50-100 mg/kg/d).

Localized lipidomics in cystic fibrosis: TOF-SIMS imaging of lungs from Pseudomonas aeruginosa-infected mice.

A consistent body of research has linked cystic fibrosis (CF) with variations in the tissue and fluid content in a number of lipid molecules. However, little is known about the spatial localization of those variations. We have recently applied TOF-SIMS mass spectrometry imaging to detect differential lipid signatures at the colon epithelium between normal and cftr-/- mice.

Cluster TOF-SIMS imaging as a tool for micrometric histology of lipids in tissue.

Recent developments in instrumentation, ion beams or analyzers, for cluster time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging are described here. The methods which are employed to increase the sensitivity or to perform three-dimensional analyses in the organic materials are also illustrated. This review shows the improvements made for lipid imaging by cluster TOF-SIMS in various types of material and applications, and gives reasons for the expansion of its utilization.

Argon cluster ion source evaluation on lipid standards and rat brain tissue samples.

Argon cluster ion sources for sputtering and secondary ion mass spectrometry use projectiles consisting of several hundreds of atoms, accelerated to 10-20 keV, and deposit their kinetic energy within the top few nanometers of the surface. For organic materials, the sputtering yield is high removing material to similar depth. Consequently, the exposed new surface is relatively damage free.

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging reveals cholesterol overload in the cerebral cortex of Alzheimer disease patients.

Although cholesterol has been involved in the pathophysiology of Alzheimer disease (AD), its distribution in the cerebral cortex over the course of AD is unknown. We describe an original method to quantify cholesterol distribution using time-of-flight secondary ion mass spectrometry imaging. Cholesterol was unevenly distributed along the cortical thickness, being more abundant close to the white matter, in both control and AD cases.