Proteins are dynamic entities that adopt diverse conformations, which play a pivotal role in their function. Understanding these conformations is essential, and protein collective motions, particularly those captured by normal mode (NM) and their linear combinations, provide a robust means for conformational sampling. This work introduces a novel approach to obtaining a uniformly oriented set of a given number of lowest frequency NM combined vectors and generating harmonically equidistant restrained structures along them.
View Article and Find Full Text PDFObesity increases serum triglycerides and decreases high-density lipoprotein cholesterol (HDL-C). The objective is to explore some functions of HDL, cholesterol transfers and antioxidant, in subjects with grade I (G1-OB) and III (G3-OB) obesity and effects of bariatric surgery on G3-OB. Fifteen G3-OB patients (43 ± 6 years, BMI 49 ± 3 kg/m) were studied before and 1 year after bariatric surgery; 15 G1-OB (32 ± 2 years, 32 ± 2 kg/m) and 15 normal weight (NW) (38 ± 6 years, 22 ± 1 kg/m) were also studied.
View Article and Find Full Text PDFMolecular Dynamics Flexible Fitting (MDFF) is a widely used tool to refine high-resolution structures into cryo-EM density maps. Despite many successful applications, MDFF is still limited by its high computational cost, overfitting, accuracy, and performance issues due to entrapment within wrong local minima. Modern ensemble-based MDFF tools have generated promising results in the past decade.
View Article and Find Full Text PDFEcology
May 2024
Camera traps became the main observational method of a myriad of species over large areas. Data sets from camera traps can be used to describe the patterns and monitor the occupancy, abundance, and richness of wildlife, essential information for conservation in times of rapid climate and land-cover changes. Habitat loss and poaching are responsible for historical population losses of mammals in the Atlantic Forest biodiversity hotspot, especially for medium to large-sized species.
View Article and Find Full Text PDFThe retreat of glaciers in Antarctica has increased in the last decades due to global climate change, influencing vegetation expansion, and soil physico-chemical and biological attributes. However, little is known about soil microbiology diversity in these periglacial landscapes. This study characterized and compared bacterial and fungal diversity using metabarcoding of soil samples from the Byers Peninsula, Maritime Antarctica.
View Article and Find Full Text PDFObjective: Mammographic screening and management of breast cancer (BC) in elderly women are controversial and continue to be an important health problem. To investigate, through members of the Senologic International Society (SIS), the current global practices in BC in elderly women, highlighting topics of debate and suggesting perspectives.
Materials And Methods: The questionnaire was sent to the SIS network and included 55 questions on definitions of an elderly woman, BC epidemiology, screening, clinical and pathological characteristics, therapeutic management in elderly women, onco-geriatric assessment and perspectives.
The mutualistic ectomycorrhizal (ECM) fungal genus Pisolithus comprises 19 species defined to date which colonize the roots of >50 hosts worldwide suggesting that substantial genomic and functional evolution occurred during speciation. To better understand this intra-genus variation, we undertook a comparative multi-omic study of nine Pisolithus species sampled from North America, South America, Asia, and Australasia. We found that there was a small core set of genes common to all species (13%), and that these genes were more likely to be significantly regulated during symbiosis with a host than accessory or species-specific genes.
View Article and Find Full Text PDFMolecular dynamics with excited normal modes (MDeNM) is an enhanced sampling method for exploring conformational changes in proteins with minimal biases. The excitation corresponds to injecting kinetic energy along normal modes describing intrinsic collective motions. Herein, we developed a new automated open-source implementation, MDexciteR (https://github.
View Article and Find Full Text PDFThe Amazon Continental Shelf (ACS) has a coastline of ∼1000 km and is situated in a humid equatorial region with two distinct seasons, wet and dry, and two transitional climatic periods. A total of eight oceanographic cruises were conducted to investigate the dynamics of the inorganic nutrients dissolved in the surface layer of the water column of the ACS and their associations with Sargassum blooms. An excess of nitrogen-N* (NH = 0.
View Article and Find Full Text PDFEnergy metabolism reprogramming was recently listed as a hallmark of cancer. In this process, the switch from pyruvate kinase isoenzyme type M1 to pyruvate kinase isoenzyme type M2 (PKM2) is believed to play a crucial role. Interestingly, the activity of the active form of PKM2 can efficiently be inhibited by the high-mobility group box 1 (HMGB1) protein, leading to a rapid blockage of glucose-dependent aerobic respiration and cancer cell death.
View Article and Find Full Text PDFObjective: Therapeutic management of ductal carcinoma (DCIS) is heterogeneous among countries worldwide, and some treatment indications are still controversial. To investigate DCIS management in different countries; identify both consensual practices and controversial topics; and survey opinions about the future management of DCIS.
Materials And Methods: The Senologic International Society network members participated to an online survey using a questionnaire, between November 2021 and February 2022.
Recent years have seen several hybrid simulation methods for exploring the conformational space of proteins and their complexes or assemblies. These methods often combine fast analytical approaches with computationally expensive full atomic molecular dynamics (MD) simulations with the goal of rapidly sampling large and cooperative conformational changes at full atomic resolution. We present here a systematic comparison of the utility and limits of four such hybrid methods that have been introduced in recent years: MD with excited normal modes (MDeNM), collective modes-driven MD (CoMD), and elastic network model (ENM)-based generation, clustering, and relaxation of conformations (ClustENM) as well as its updated version integrated with MD simulations (ClustENMD).
View Article and Find Full Text PDFThere is increasing support for water molecules playing a role in signal propagation through G protein-coupled receptors (GPCRs). However, exploration of the hydration features of GPCRs is still in its infancy. Here, we combined site-specific labeling with unnatural amino acids to molecular dynamics to delineate how local hydration of the ghrelin receptor growth hormone secretagogue receptor (GHSR) is rearranged upon activation.
View Article and Find Full Text PDFThe water quality and trends in 12 tropical rivers in northeastern Brazil over a 27-year period (1990-2016; N = 39,008 samples) were evaluated. The analyzed parameters included temperature, conductivity, pH, dissolved oxygen (DO), biochemical oxygen demand (BOD), nitrogen (NH), total phosphorus (P), and fecal coliforms. Densely populated basins (> 1000 inhab km) presented lower DO values (average 3.
View Article and Find Full Text PDFIn early 2020, the book "Breast cancer: Global Quality Care" was published by Oxford University Press. In the year since then, publications, interviews (by ecancer), presentations, webinars, and virtual congress have been organized to disseminate further the main message of the project: "A call for Fairer Breast Cancer Care for all Women in a Globalized World." Special attention is paid to increasing the "value-based healthcare" putting the patient in the center of the care pathway and sharing information on high-quality integrated breast cancer care.
View Article and Find Full Text PDFBackground: MicroRNAs (miRs) play critical roles in regulation of numerous biological events, including cardiac electrophysiology and arrhythmia, through a canonical RNA interference mechanism. It remains unknown whether endogenous miRs modulate physiologic homeostasis of the heart through noncanonical mechanisms.
Methods: We focused on the predominant miR of the heart (miR1) and investigated whether miR1 could physically bind with ion channels in cardiomyocytes by electrophoretic mobility shift assay, in situ proximity ligation assay, RNA pull down, and RNA immunoprecipitation assays.
Introduction: The COVID-19 pandemic has changed health systems across the world, both in general hospitals and in oncology institutes or centres.For cancer specialists, particularly breast cancer (BC), the COVID-19 pandemic represents a combination of challenges since the hospital resources and staff have become more limited; this has obliged oncology specialists to seek a consensus and establish which patients with BC require more urgent attention and which patients can wait until there is a better control of this pandemic. The health system in Latin America has some special characteristics; in some of the countries, there are shortages which limit access to several specialities (surgery, clinical oncology and radiotherapy) in some regions.
View Article and Find Full Text PDFIn this review, we present the state of art regarding rhizosphere effects on eucalypt plantations. It provides a greater understanding of carbon (C) and nitrogen (N) turnover in forest soils. P organic hydrolysis, soil mineral solubilization, indoleacetic acid, gibberellin, resistance factors, and production of siderophores by rhizosphere microbial populations help to explain the tolerance of Eucalyptus plants to biotic and abiotic stresses and the apparent steady-state condition of C and N soil stocks in many planted forests.
View Article and Find Full Text PDFNetwork theory methods and molecular dynamics (MD) simulations are accepted tools to study allosteric regulation. Indeed, dynamic networks built upon correlation analysis of MD trajectories provide detailed information about communication paths between distant sites. In this context, we aimed to understand whether the efficiency of intramolecular communication could be used to predict the allosteric potential of a given site.
View Article and Find Full Text PDFPathogenic microbes are known to manipulate the defences of their hosts through the production of secreted effector proteins. More recently, mutualistic mycorrhizal fungi have also been described as using these secreted effectors to promote host colonization. Here we characterize a mycorrhiza-induced small secreted effector protein of 10 kDa produced by the ectomycorrhizal fungus Pisolithus albus, PaMiSSP10b.
View Article and Find Full Text PDFThe aim of this study was to evaluate the expression of human leukocyte antigen G (HLA-G) in leprosy. Biopsy and serum samples were collected from 18 patients presenting with leprosy and from healthy controls. Samples were analyzed using immunohistochemistry and ELISA techniques.
View Article and Find Full Text PDFPrevious studies demonstrated the efficiency of the Molecular Dynamics with excited Normal Modes (MDeNM) method on the characterization of large structural changes at a low computational cost. We present here MDeNM-EMfit, an extension of the original method designed to the flexible fit of structures into cryo-EM maps. Here, instead of a uniform exploration of the collective motions described by normal modes, sampling is directed toward conformations with increased correlations with the experimental map.
View Article and Find Full Text PDFThe aim of this study was to identify genes with higher expression in solid tumor cells by comparing human tumor biopsies with healthy blood samples using both in silico statistical analysis and experimental validations. This approach resulted in a novel panel of 80 RNA biomarkers with high discrimination power to detect circulating tumor cells in blood samples. To identify the 80 RNA biomarkers, Affymetrix HG-U133 plus 2.
View Article and Find Full Text PDFBiochim Biophys Acta Proteins Proteom
January 2020
Fungi cellulases are used to degrade cellulose-containing biomass for bioethanol production. Industrial cellulases such as Cel7A from Trichoderma reesei (TrCel7A) are critical in this process. Thus, the understanding of structure and dynamics is crucial for engineering variants with improved cellulolytic activity.
View Article and Find Full Text PDF