Randomized open-label controlled study of cancer vaccine OSE2101 versus chemotherapy in HLA-A2-positive patients with advanced non-small-cell lung cancer with resistance to immunotherapy: ATALANTE-1.

BACKGROUND: Patients with advanced non-small-cell lung cancer (NSCLC) treated with immune checkpoint blockers (ICBs) ultimately progress either rapidly (primary resistance) or after durable benefit (secondary resistance). The cancer vaccine OSE2101 may invigorate antitumor-specific immune responses after ICB failure. The objective of ATALANTE-1 was to evaluate its efficacy and safety in these patients. PATIENTS AND METHODS: ATALANTE-1 was a two-step open-label study to evaluate the efficacy and safety of OSE2101 compared to standard-of-care (SoC) chemotherapy (CT). Patients with human leukocyte antigen (HLA)-A2-positive advanced NSCLC without actionable alterations, failing sequential or concurrent CT and ICB were randomized (2 : 1) to OSE2101 or SoC (docetaxel or pemetrexed). Primary endpoint was overall survival (OS). Interim OS futility analysis was planned as per Fleming design. In April 2020 at the time of interim analysis, a decision was taken to prematurely stop the accrual due to coronavirus disease 2019 (COVID-19). Final analysis was carried out in all patients and in the subgroup of patients with ICB secondary resistance defined as failure after ICB monotherapy second line ≥12 weeks. RESULTS: Two hundred and nineteen patients were randomized (139 OSE2101, 80 SoC); 118 had secondary resistance to sequential ICB. Overall, median OS non-significantly favored OSE2101 over SoC {hazard ratio (HR) [95% confidence interval (CI)] 0.86 [0.62-1.19], P = 0.36}. In the secondary resistance subgroup, OSE2101 significantly improved median OS versus SoC [11.1 versus 7.5 months; HR (95% CI) 0.59 (0.38-0.91), P = 0.017], and significantly improved post-progression survival (HR 0.46, P = 0.004), time to Eastern Cooperative Oncology Group (ECOG) performance status deterioration (HR 0.43, P = 0.006) and Quality of Life Questionnaire Core 30 (QLQ-C30) global health status compared to SoC (P = 0.045). Six-month disease control rates and progression-free survival were similar between groups. Grade ≥3 adverse effects occurred in 11.4% of patients with OSE2101 and 35.1% in SoC (P = 0.002). CONCLUSIONS: In HLA-A2-positive patients with advanced NSCLC and secondary resistance to immunotherapy, OSE2101 increased survival with better safety compared to CT. Further evaluation in this population is warranted.

Biomedical Nanosystems for In Vivo Detoxification: From Passive Delivery Systems to Functional Nanodevices and Nanorobots.

The problem of low efficiency of nanotherapeutic drugs challenges the creation of new alternative biomedical nanosystems known as robotic nanodevices. In addition to encapsulating properties, nanodevices can perform different biomedical functions, such as precision surgery, in vivo detection and imaging, biosensing, targeted delivery, and, more recently, detoxification of endogenous and xenobiotic compounds. Nanodevices for detoxification are aimed at removing toxic molecules from biological tissues, using a chemical- and/or enzyme-containing nanocarrier for the toxicant to diffuse inside the nanobody. This strategy is opposite to drug delivery systems that focus on encapsulating drugs and releasing them under the influence of external factors. The review describes various kinds of nanodevices intended for detoxification that differ by the type of poisoning treatment they provide, as well as the type of materials and toxicants. The final part of the review is devoted to enzyme nanosystems, an emerging area of research that provides fast and effective neutralization of toxins in vivo.

Correlation-based ultrasound imaging of strong reflectors with phase coherence filtering.

Two main metrics are usually employed to assess the quality of medical ultrasound (US) images, namely the contrast and the spatial resolution. A number of imaging algorithms have been proposed to improve one of those metrics, often at the expense of the other one. This paper presents the application of a correlation-based ultrasound imaging method, called Excitelet, to medical US imaging applications and the inclusion of a new Phase Coherence (PC) metric within its formalism. The main idea behind this algorithm, originally developed and validated for Non-Destructive Testing (NDT) applications, is to correlate a reference signal database with the measured signals acquired from a transducer array. In this paper, it is shown that improved lateral resolutions and a reduction of imaging artifacts are obtained over the Synthetic Aperture Focusing Technique (SAFT) when using Excitelet in conjunction with a PC filter. This novel method shows potential for the imaging of specular reflectors, such as invasive surgical tools. Numerical and experimental results presented in this paper demonstrate the benefit, in terms of contrast and resolution, of using the Excitelet method combined with PC for the imaging of strong reflectors.

The Effect of Viscosity and Application Mode of Phosphoric Acid on Bond Strength of GlassFiber Post.

BACKGROUND: When a phosphoric acid is used, before applying an adhesive system, it is known that obtaining an effective adhesion to the root canal walls is a challenge. The aim of the present study was to evaluate the influence of phosphoric acid viscosity and application mode on the push-out bond strength (BS) values of fiberglass post to root dentin. The conditioning pattern on the root dentin was also evaluated. MATERIALS AND METHODS: The roots of 44 endodontically treated premolars were divided into 4 groups, of eleven teeth each, according to the combination of the main factors: phosphoric acid viscosity (liquid or gel) and application mode (passive or sonic). After application of the two-step etch-and-rinse adhesive system, the fiberglass posts were cemented with a dual-cure resin-cement. Roots were sectioned transversely into six 1-mm slices for push-out BS test at 0.5 mm/min. Some roots of each group were selected for evaluation of the conditioning pattern by scanning electron microscopy. BS results (three-way ANOVA and Tukey's test) and the conditioning pattern (Kruskal-Wallis test and Mann-Whitney test) were statistically evaluated (α= 0.05). RESULTS: The highest BS value was observed with a liquid phosphoric acid under sonic application mode (p < 0.05), being all other groups similar to one another (p < 0.05). Also, the highest BS value was observed in the cervical third, followed by the medium and the apical thirds (p < 0.05). The sonic application produced better smear layer removal and opening of dentinal tubules for both viscosities (p = 0.015). CONCLUSION: A better bonding of fiberglass posts to root canals can be achieved when the post spaces are conditioned with a liquid phosphoric acid under sonic application.

Photoprotection of the future: challenges and opportunities.

The use of sunscreens is an important and essential component of photoprotection. Since their introduction during the first half of the last century, sunscreens have benefited enormously from major technological advances such as the development of novel UV filters; as a result, their efficacy in preventing UV-induced erythema is unequivocal. More recently, however, new challenges have appeared, which have prompted a robust discussion about the safety of sunscreens. These include topics directly related to photoprotection of human skin such as improved/alternative methods for standardization of assessment of the efficacy of sunscreens, but also many others such as photoprotection beyond UV, concerns about human toxicity and ecological safety, the potential of oral photoprotective measures, consequences of innovative galenic formulations. On a first glance, some of these might raise questions and doubts among dermatologists, physicians and the general public about the use sunscreens as a means of photoprotection. This situation has prompted us to critically review such challenges, but also opportunities, based on existing scientific evidence. We conclude by providing our vision about how such challenges can be met best in the future in an attempt to create the ideal sunscreen, which should provide adequate and balanced protection and be easy and safe to use.

Analysis of physical exercise in cardiac patients following cardiovascular rehabilitation.

Background: Cardiovascular rehabilitation and retraining seek to increase cardiorespiratory fitness and to manage certain risk factors such as smoking, hypercholesterolaemia and sedentary lifestyle. Such lifestyle changes can be influenced by a combination of health determinants.Aim: The purpose of this study is to analyse the profile (health determinants) of patients who continue to practice a physical activity and who are following guidelines for physical activity, at one year after rehabilitation.Methods: One hundred patients (23 women and 77 men) with an average age of 59.9 years (±10.42) were monitored. The level of physical activity of these patients was measured with weekly journals and with the International Physical Activity Questionnaire (IPAQ).Results: We found that 46.4% of patients did not follow the recommendations for physical exercise. In addition, patients from higher social strata and those with higher levels of education were more inclined to continue to practice physical activity.Conclusions: Our results suggest that professional practices and patient education would benefit from a greater understanding of social and cultural determinants, and that this would also promote patient compliance with instructions regarding physical activity.

Feedback on the usefulness of an illustrated guidebook in an anatomical dissection course.

PURPOSE: Dissection provides direct experience in anatomy, which constitutes an essential discipline for medical students. For this purpose, we created a dissection guide for students in the 2nd-year of medical studies at the Grenoble University School of Medicine. The objective was to evaluate this tool of reverse pedagogy in terms of student satisfaction and educational interest. METHODS: Every 2nd-year student takes four sessions of limb dissection. To assist this dissection course, we developed a photographic guide launched in 2013. It includes an introduction presenting a methodology for dissection, followed by detailed protocols for each dissection area. Each step is illustrated with captioned photographs associated with a concise explanatory text. A questionnaire was then sent to 242 students to assess the impact of this tool and their overall satisfaction. RESULTS: Overall student satisfaction with this guidebook was rated 8.1 out of 10 with a 93.2% with significant improvement (p = 0.0137) and 78.7% of them declaring they had a better understanding of anatomy and mastery of the dissection techniques, respectively. In addition, students assessed the usefulness of the dissection guide at 3.6 out of 4 with the relevance of the content and presentation judged at 3.4 out of 4. Finally, the exam scores increased significantly with use of the guidebook (p < 0.0001). CONCLUSIONS: Students deemed the organization of this anatomy tutorial as highly satisfactory, and using the guidebook as a reference in dissection sessions allowed students to prepare for the dissection and improve their knowledge of anatomy, as demonstrated by improved exam scores.

[Therapeutic strategies in patients undergoing surgery for non-small cell lung cancer. Results of the ESCAP-2011-CPHG study, promoted by the French College of General Hospital Respiratory Physicians (CPHG)]. / Stratégies thérapeutiques chez les patients opérés pour un carcinome bronchique non à petites cellules. Résultats de l'étude ESCAP-2011-CPHG réalisée par le Collège des pneumologues des hôpitaux généraux (CPHG).

BACKGROUND: The aim of ESCAP-2011-CPHG, promoted by the French College of General Hospital Respiratory Physicians, was to describe therapeutic strategies in lung cancer in the first 2 years after diagnosis, in a real-life setting. This article focuses on patients undergoing surgical management of a non-small cell lung cancer (NSCLC). METHODS: A prospective multicentre study was conducted in 53 French general hospitals. For each patient with lung cancer diagnosed in 2010, a standardised form was completed following each change in treatment strategy up to 2 years after diagnosis. RESULTS: Overall, 3418 of the 3943 included patients had NSCLC. 741 patients (21.7%) underwent curative surgery (stage 0-II, IIIA, IIIB, and IV: 65%, 27%, 3% and 5%, respectively). The therapeutic strategy changed less often in surgical than non-surgical patients and average follow-up time was longer: 23.3 months (SD: 9.3) versus 10.4 months (SD: 9.5) for non-surgical patients. Among patients with a surgical first strategy (92.6% of surgical patients as a whole), 56.9% did not receive any other treatment, 34.7% received chemotherapy, 5.9% radio-chemotherapy, 2.6% radiotherapy. At the end of follow-up, 55.8% were still alive without any other strategy, 13.1% had died, and 31.1% had received at least one more strategy. Among patients with a surgical second strategy, 63% had received chemotherapy alone during the first strategy. CONCLUSIONS: ESCAP -2011- CPHG assessed everyday professional practice in the surgical management of NSCLC in general hospitals. It pointed out the discrepancies between current guidelines and the therapeutic strategies applied in real life conditions.

Application of Tetrameric Recombinant Human Butyrylcholinesterase as a Biopharmaceutical for Amelioration of Symptoms of Acute Organophosphate Poisoning.

We present a procedure for optimizing the expression of recombinant tetrameric butyrylcholinesterase that enables large-scale production with the yield >30 mg/liter (>90 mg/roller bottle). Intravenous injection of the preparation significantly increased survival and decreased the severity of symptoms of poisoning with paraoxon, an organophosphorus toxin.

[Pleurisy induced by atorvastatin]. / Pleurésie induite par l'atorvastatine.

INTRODUCTION: Whereas numerous case reports have described statin-induced lung injuries, statin-induced pleural effusions are uncommon. CASE REPORT: An 84-year-old man presented with bilateral pleural effusions two years after starting treatment with atorvastatin. No other cause of pleural effusion was found and all symptoms and radiological signs resolved rapidly after discontinuation of the drug. Furthermore, an accidental reintroduction of the treatment resulted in recurrence of the same clinical picture, reinforcing the hypothesis that atorvastatin was responsible for this pleural effusion. CONCLUSION: Pleuropulmonary manifestations in a patient treated with atorvastatin should rapidly evoke an iatrogenic origin and the discontinuation of the drug should be discussed.

Accumulation of Cd, Cu and Zn in shoots of maize (Zea mays L.) exposed to 0.8 or 20 nM Cd during vegetative growth and the relation with xylem sap composition.

This work focuses on the exposure of maize plants to nanomolar concentrations of Cd, which is relevant for agricultural soils cropped with food and feed plants. Maize plants were cultivated in nutrient solution at 0.8 or 20 nM Cd during the vegetative growth stages. No significant hormesis or toxic effects of Cd were observed on maize growth, but a decrease in the allocation of Cd to shoots between the 0.8 and 20 nM Cd exposures revealed that the plants already responded to these low concentrations of Cd according to a shoot Cd excluder strategy. The Cd, Cu and Zn concentrations in shoots decreased with time as the result of an early decrease in the root/shoot ratio and of a decrease in the coefficient of allocation to aboveground for Zn and Cd at 20 nM. As a consequence, shoots of young plants were richer in micronutrients Cu and Zn but also in toxic Cd. The rate of delivery of Cd, Cu and Zn from xylem sap was successfully used to predict the time course of concentrations of Cd, Cu and Zn in the shoot. However, it overestimated the actual concentrations of Cd in the shoot, presumably because the reallocation of this trace element from shoots back to roots was not taken into account.

Morphological, structural and biophysical properties of French and Brazilian photoaged skin.

BACKGROUND: Knowledge of skin biology and its alterations in different populations is very important for the development of appropriate skincare strategies. OBJECTIVES: To evaluate and compare morphological, structural and biophysical properties of photoaged skin in French and Brazilian populations, using biophysical and skin-imaging techniques. METHODS: Forty-one French and 41 Brazilian healthy, female volunteers aged between 40 and 65 years were enrolled. Each participant completed a questionnaire concerning habits related to cosmetic use, sun exposure and sun protection during different life periods. Skin on the face and volar forearm was evaluated using noninvasive techniques, to determine skin colour, transepidermal water loss (TEWL), stratum corneum water content, skin microrelief, skin viscoelasticity and dermis structure. Reflectance confocal microscopy was used to measure epidermal layer thickness and epidermal morphological and structural characteristics. RESULTS: Compared with Brazilian skin, French skin was more hydrated, had a lower TEWL and presented a distinct viscoelastic profile on the forearms and face. Brazilian facial skin was more wrinkled, and the dermis was less echogenic on the forearms and face. The French participants had thicker stratum corneum. Brazilian facial skin presented a higher prevalence of rete ridge effacement, low interkeratinocyte reflectance, huddled collagen and solar elastosis. CONCLUSIONS: Morphological, structural and biophysical differences were found when assessing the skin of the Brazilian and French participants, who were exposed to different environmental factors.

6-Methyluracil derivatives as acetylcholinesterase inhibitors for treatment of Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is the major age-related progressive neurodegenerative disorder. The brain of AD patients suffers from loss of cholinergic neurons and decreased number of synapses [1]. AD is caused by an imbalance between Aß production and clearance, resulting in increased amount of Aß in various forms [2]. Reduction of Aß production and increasing clearance of Aß pathogenic forms are key targets in the development of potential therapeutic agents for AD treatment. Unfortunately, only nosotropic approaches for treatment of AD are currently effective in humans. These approaches mainly focus on the inhibition of brain acetyl-cholinesterase (AChE) to increase lifetime of cerebral acetylcholine [3]. It is important to emphasize that AChE itself promotes the formation of Aß fibrils in vitro and Aß plaques in the cerebral cortex of transgenic mouse models of AD [4]. This property of AChE results from interaction between Aß and the peripheral anionic site of the enzyme (PAS) [5]. Dual binding site inhibitors of both catalytic active site (CAS) and PAS can simultaneously improve cognition and slow down the rate of Aß-induced neural degeneration. Unfortunately, the assortment of AChE PAS ligands is still extremely limited. OBJECTIVE: To study putative advantages of AChE non-charged PAS inhibitors based on 6-methyluracil derivatives for the treatment of Alzheimer's disease. METHODS: In vitro studies. Concentration of drug producing 50% of AChE/BuChE activity inhibition (IC50) was measured using the method of Ellman et al. [6]. Toxicological experiments were performed using IP injection of the different compounds in mice. LD50, dose (in mg/kg) causing lethal effects in 50% of animals was taken as a criterion of toxicity [7]. The ability of compound to block in vitro AChE-induced Aß1-40 aggregation was studied using a thioflavin T (ThT) fluorescent probe [8].In vivo biological assays. For in vivo blood-brain barrier permeation assay brains were removed 30 min after IP injection of LD50 dose of tested compound injection. The inhibitory potency was measured using the method of Ellman.Scopolamine and transgenic models of AD were used to evaluate the influence of compound 35 on spatial memory performance.Water solution of scopolamine was injected to mice (ip) 20 minutes before starting memory test during 14 days [9]. Mice were assigned to 7 groups, including 4 groups receiving injection (ip) of compound in different dosages, donepezil-treated mice (donepezil is conventionally used to treat Alzheimer's disease), positive and negative control groups. Double transgenic (APP/PS1) mice expressing a chimeric mouse/human amyloid precursor protein and a mutant of human presenilin-1 [10] were assigned to 4 groups, including transgenic animals injected (ip) with compound 35 or donepezil solution, positive (transgenes injected with water) and negative (wild-type mice) controls.To evaluate spatial memory performance, mice were trained on a reward alternation task using a conventional T-maze [11]. The criterion for a mouse having learned the rewarded alternation task was 3 consecutive days of at least 5 correct responses out of the 6 free trials.For ß-amyloid peptide load was evaluated quantitatively as a number and summary area of Thioflavine S fluorescent spots in cerebral cortex and hippocampal images using Image J program. Statistical analyses were performed using the Mann-Whitney test. RESULTS: We evaluated the acute toxicity of the most active compounds. The most potent AChE inhibitor compound 35 (IC50 (AChE) = 5 ± 0.5 nM) exhibited the lowest LD50 values (51 mg/kg) and inhibited brain AChE by more than 71 ± 1%. Compound 35 at 10 nM, exhibited a significant (35 ± 9%) inhibitory activity toward human AChE-induced Aß aggregation.Scopolamine injection induced significant decrease in correct choice percentage in T-maze, as well as decrease in percentage of mice reaching criterion for learning the task by day 14. This memory deficit was relieved to some extent either by compound 35 (5 mg/kg) or donepezil (reference compound) treatment (0.75 mg/kg). Interestingly, higher doses of compound 35 (10 and 15 mg/kg) produced less therapeutic effect on spatial memory deficit.Group of APP/PS1 mice showed 3 times lower percentage of reaching behavioral criterion and lower percentage of correct choice in T-maze alternation task comparing to WT mice, whereas compound 35 (5 mg/kg) or Donepezil treatment effectively improved these parameters in APP/PS1 mice.Compound 35 treatment (5 mg/kg) during 14 days significantly reduced percentage of summary area and number of ß-amyloid peptide (ßAP) deposits visualized in sections of cerebral cortex, dentate gyrus, and hippocampal CA3 area in APP/PS1 mice. The most prominent reduction of ßAP load by compound 35 treatment was found in CA3 area and cerebral cortex. Meanwhile, Donepezil treatment (1 mg/kg) during 14 days significantly reduced ßAP load in cerebral cortex but not in dentate gyrus and CA3 area. CONCLUSIONS: Experiments showed that the most potent AChE inhibitor compound 35 (6-methyluracil derivative) permeated the blood-brain barrier, improved working memory in the APP/PS1 transgenic mice and significantly reduced the number and area of Aß plaques in the brain. Thus, compound 35 is a promising candidate as a bi-functional inhibitor of AChE for treatment of AD.

Molecular modeling of mechanism of action of anti-myasthenia gravis slow-binding inhibitor of acetylcholinesterase.

BACKGROUND: Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder characterized by fluctuating weakness of voluntary skeletal muscles. The cause of autoimmune response is unknown and only symptomatic therapies for MG are currently available. Pharmacological correction of synaptic failure underlying MG, involves partial inhibition acetyl- and butyrylcholinesterase. Effectiveness of cholinesterase inhibitors in the symptomatic treatment of MG is based on their ability to potentiate the effects of acetylcholine by decreasing the rate of its enzymatic hydrolysis at neuromuscular junctions. Several new inhibitors of AChE were tested in animal model of MG and may be considered as valuable candidates for the treatment of pathological muscle weakness syndromes. In this study, we have investigated mechanisms of ChE inhibition by one of the most active 6-methyluracil derivatives (C547), as well as the possible benefits of using this compound for MG treatment compared to traditionally used pyridostigmine bromide.It was experimentally shown that C547 is a «pseudo-irreversible¼ slow-binding inhibitor of human AChE. Human BChE is reversibly inhibited by C547 with an affinity about 4 orders of magnitude lower than that of human AChE. Slow-binding inhibition of AChE leads to a lasting (over 24 hours) effect on the symptoms of muscle weakness in animal model of MG after a single administration of C547. OBJECTIVE: The aim of the present molecular modeling study was to reveal mechanism of AChE inhibition by C547 and elucidate its apparent «pseudo-irreversibility¼. METHODS: Two principle methods used in the present study were molecular docking and molecular dynamics (MD). Molecular docking was performed with Autodock 4.2.6 software, Lamarckian Genetic Algorithm to obtain structure of protein inhibitor complexes and Local Search for MD snapshots to compare relative binding affinity. For MD simulations NAMD 2.10 software with Charrm 36 force field was used, for the ligand C547 Charmm General Force Field was used, and missing parameters were obtained with quantum mechanical calculations. Unconstrained MD, steered MD (SMD) and free energy calculations with adaptive biasing force were performed. RESULTS: During unconstrained MD, C547 very rapidly binded to the peripheral anionic site (PAS) of AChE. To pass the bottleneck, application of the external force was required (SMD). Both SMD modelling and free energy calculation revealed that after crossing the AChE bottleneck, C547 falls into very favorable position. At the same time the rupture of interactions as well as overcoming the bottleneck gates in the course of pulling out procedure requires application of much higher force than during the pulling-in process. This difference between binding and dissociating processes explains apparent «pseudo-irreversibility¼ of the inhibitor. CONCLUSIONS: These findings are in good agreement with kinetics study showing that C-547 is a slow-binding inhibitor of type B, i.e. after rapid initial binding of inhibitor, the enzyme-inhibitor complex undergoes an isomerization step. Position obtained by SMD is in good agreement with X-ray data obtained by F. Nachon, IBS, France.

Human butyrylcholinesterase polymorphism: Molecular modeling.

BACKGROUND: Prolonged apnoea following injection of ester-containing myoralaxants was first described in 1953. Because a large part of administered succinylcholine is shortly hydrolyzed by plasma butyrylcholinesterase (BChE) under normal conditions, prolonged apnoea was attributed to deficiency in BChE. It was found that BChE deficiency was due to genetic variations. Human BChE gene shows a large polyallelism. About 75 natural mutations of the BCHE gene have been documented so far [1]. Most of them cause alteration in BChE activity through point mutation effect on catalytic activity. Frame shifts and stop codons may also affect expression, or cause truncations in the sequence. OBJECTIVE: Recently, two novel BChE "silent" variants, Val204Asp [2] and Ala34Val [3], causing prolonged neuromuscular block after administration of mivacurium, were discovered. Mutations were genetically and kinetically characterized. The aim of the current study was to understand how these mutations determine "silent" phenotype. METHODS: Molecular dynamics studies were carried out with NAMD 2.9 software at the Lomonosov supercomputer. Charmm 36 force field was used, periodical boundary conditions, 1 atm pressure, 298 K. 100 ns molecular dynamics runs were performed for the wild-type BChE and its mutants Val204Asp and Ala34Val. RESULTS: Unlike wild-type BChE, which retained its operative catalytic triad through the whole MD simulation, the catalytic triad of mutants was disrupted, making chemical step impossible. Val204Asp mutation leads to reorganization of hydrogen bonding network around the catalytic triad, which in turn increases the distance between catalytic residue main chains. Mutation Ala34Val, located on the protein surface, leads to increased fluctuations in the Ω-loop and subsequent disruption of the gorge structure, including disruption of the catalytic triad and formation of new hydrogen bonds involving catalytic center residues. CONCLUSIONS: Comparative study of the "silent" Ala328Asp mutant and the catalytically active mutant Ala328Cys shows that MD approach can discriminate between the differential effects of point mutations at a same position.

Representing virus-host interactions and other multi-organism processes in the Gene Ontology.

BACKGROUND: The Gene Ontology project is a collaborative effort to provide descriptions of gene products in a consistent and computable language, and in a species-independent manner. The Gene Ontology is designed to be applicable to all organisms but up to now has been largely under-utilized for prokaryotes and viruses, in part because of a lack of appropriate ontology terms. METHODS: To address this issue, we have developed a set of Gene Ontology classes that are applicable to microbes and their hosts, improving both coverage and quality in this area of the Gene Ontology. Describing microbial and viral gene products brings with it the additional challenge of capturing both the host and the microbe. Recognising this, we have worked closely with annotation groups to test and optimize the GO classes, and we describe here a set of annotation guidelines that allow the controlled description of two interacting organisms. CONCLUSIONS: Building on the microbial resources already in existence such as ViralZone, UniProtKB keywords and MeGO, this project provides an integrated ontology to describe interactions between microbial species and their hosts, with mappings to the external resources above. Housing this information within the freely-accessible Gene Ontology project allows the classes and annotation structure to be utilized by a large community of biologists and users.

Chemical Polysialylation and In Vivo Tetramerization Improve Pharmacokinetic Characteristics of Recombinant Human Butyrylcholinesterase-Based Bioscavengers.

Organophosphate toxins (OPs) are the most toxic low-molecular compounds. The extremely potent toxicity of OPs is determined by their specificity toward the nerve system. Human butyrylcholinesterase (hBChE) is a natural bioscavenger against a broad spectrum of OPs, which makes it a promising candidate for the development of DNA-encoded bioscavengers. The high values of the protective index observed for recombinant hBChE (rhBChE) make it appropriate for therapy against OP poisoning, especially in the case of highly toxic warfare nerve agents. Nevertheless, large-scale application of biopharmaceuticals based on hBChE is restricted due to its high cost and extremely rapid elimination from the bloodstream. In the present study, we examine two approaches for long-acting rhBChE production: I) chemical polysialylation and II) in-vivo tetramerization. We demonstrate that both approaches significantly improve the pharmacokinetic characteristics of rhBChE (more than 5 and 10 times, respectively), which makes it possible to use rhBChE conjugated with polysialic acids (rhBChE-CAO) and tetrameric rhBChE (4rhBChE) in the treatment of OP poisonings.

Pressure-induced molten globule state of human acetylcholinesterase: structural and dynamical changes monitored by neutron scattering.

We used small-angle neutron scattering (SANS) to study the effects of high hydrostatic pressure on the structure of human acetylcholinesterase (hAChE). At atmospheric pressure, our SANS results obtained on D11 at ILL (Grenoble, France) give a radius of gyration close to that calculated for a mixture of monomers, dimers and tetramers of the enzyme, suggesting a good agreement between hAChE crystal structure and its conformation in solution. Applying high pressure to the sample we found a global compression of about 11% of the enzyme up to a pressure of 900 bar and then again an extension up to 2.1 kbar indicating unfolding of the tertiary structure due to a molten globule (MG) state. On the other hand, we studied the influence of pressure up to 6 kbar on the dynamics of this enzyme, on the backscattering spectrometer IN13 at ILL. For the first time, we used elastic incoherent neutron scattering (EINS) to probe the differences between hAChE in its folded state (N), its high-pressure induced MG state and its unfolded state (U). Especially around the MG state at 1750 bar we found a significant increase in the dynamics, indicating a partial unfolding. A four-step-model is suggested to describe the changes in the protein.

Correlation of the dynamics of native human acetylcholinesterase and its inhibited huperzine A counterpart from sub-picoseconds to nanoseconds.

It is a long debated question whether catalytic activities of enzymes, which lie on the millisecond timescale, are possibly already reflected in variations in atomic thermal fluctuations on the pico- to nanosecond timescale. To shed light on this puzzle, the enzyme human acetylcholinesterase in its wild-type form and complexed with the inhibitor huperzine A were investigated by various neutron scattering techniques and molecular dynamics simulations. Previous results on elastic neutron scattering at various timescales and simulations suggest that dynamical processes are not affected on average by the presence of the ligand within the considered time ranges between 10 ps and 1 ns. In the work presented here, the focus was laid on quasi-elastic (QENS) and inelastic neutron scattering (INS). These techniques give access to different kinds of individual diffusive motions and to the density of states of collective motions at the sub-picoseconds timescale. Hence, they permit going beyond the first approach of looking at mean square displacements. For both samples, the autocorrelation function was well described by a stretched-exponential function indicating a linkage between the timescales of fast and slow functional relaxation dynamics. The findings of the QENS and INS investigation are discussed in relation to the results of our earlier elastic incoherent neutron scattering and molecular dynamics simulations.

Intermittent androgen deprivation is a rational standard-of-care treatment for all stages of progressive prostate cancer: results from a systematic review and meta-analysis.

BACKGROUND: The optimal hormone treatment strategy in prostate cancer is uncertain, particularly in patients with metastatic disease. We aimed to compare the relative benefits and harms of intermittent androgen deprivation (IAD) to continuous androgen deprivation (CAD) in all stages of prostate cancer. METHODS: We included eight randomised control trials (4668 patients) in our systematic review and meta-analysis. Median follow-up ranged from 29 to 118 months. Pooled hazard ratios (HRs) were calculated for overall survival (OS), cancer-specific survival, time to cancer progression and mortality unrelated to prostate cancer. The relative effect of treatment in patients with metastatic and those with non-metastatic disease was compared using pre-planned subgroup analysis. RESULTS: There was no difference in OS between patients treated with IAD and CAD (HR 1.01, 95% confidence interval (CI) 0.93-1.10); nor was there any difference in cancer-specific survival (HR 1.03; 95% CI 0.88-1.21). There was a non-significant trend towards longer time to prostate cancer progression for IAD (HR 0.93, 95% CI 0.84-1.04), raising the possibility of slower selection for castrate resistance. There was no significant difference in OS when analysis was restricted to patients with metastatic disease (HR 1.04, 95% CI 0.91-1.19) or patients without metastatic disease (HR 1.06, 95% CI 0.91-1.23) (test for subgroup differences P=0.84). Most studies found an improvement in quality of life or toxicity profile with IAD. CONCLUSIONS: IAD is non-inferior to CAD in terms of OS and cancer-specific survival, and is at least non-inferior in terms of time to progression. This meta-analysis confirms IAD as a valid standard of care for managing prostate cancer patients.