Specific Complex Research Articles

Heterogeneous Expression and Subcellular Localization of Pyruvate Dehydrogenase Complex in Prostate Cancer.

BackgroundPyruvate dehydrogenase (PDH) complex converts pyruvate into acetyl-CoA by pyruvate decarboxylation, which drives energy metabolism during cell growth, including prostate cancer (PCa) cell growth. The major catalytic subunit of PDH, PDHA1, is regulated by phosphorylation/dephosphorylation by pyruvate dehydrogenase kinases (PDKs) and pyruvate dehydrogenase phosphatases (PDPs). There are four kinases, PDK1, PDK2, PDK3 and PDK4, which can phosphorylate and inactivate PDH; and two phosphatases, PDP1 and PDP2, that dephosphorylate and activate PDH.MethodsWe have analyzed by immunohistochemistry the expression and clinicopathological correlations of PDHA1, PDP1, PDP2, PDK1, PDK2, PDK3, and PDK4, as well as of androgen receptor (AR), in a retrospective PCa cohort of patients. A total of 120 PCa samples of representative tumor areas from all patients were included in tissue microarray (TMA) blocks for analysis. In addition, we studied the subcellular localization of PDK2 and PDK3, and the effects of the PDK inhibitor dichloroacetate (DCA) in the growth, proliferation, and mitochondrial respiration of PCa cells.ResultsWe found heterogeneous expression of the PDH complex components in PCa tumors. PDHA1, PDP1, PDK1, PDK2, and PDK4 expression correlated positively with AR expression. A significant correlation of PDK2 immunostaining with biochemical recurrence and disease-free survival was revealed. In PCa tissue specimens, PDK2 displayed cytoplasmic and nuclear immunostaining, whereas PDK1, PDK3 and PDK4 showed mostly cytoplasmic staining. In cells, ectopically expressed PDK2 and PDK3 were mainly localized in mitochondria compartments. An increase in maximal mitochondrial respiration was observed in PCa cells upon PDK inhibition by DCA, in parallel with less proliferative capacity.ConclusionOur findings support the notion that expression of specific PDH complex components is related with AR signaling in PCa tumors. Furthermore, PDK2 expression associated with poor PCa prognosis. This highlights a potential for PDH complex components as targets for intervention in PCa.

Dcp2 C-terminal cis-binding elements control selective targeting of the decapping enzyme by forming distinct decapping complexes.

A single Dcp1-Dcp2 decapping enzyme targets diverse classes of yeast mRNAs for decapping-dependent 5' to 3' decay, but the molecular mechanisms controlling mRNA selectivity by the enzyme remain elusive. Through extensive genetic analyses we reveal that Dcp2 C-terminal domain cis-regulatory elements control decapping enzyme target specificity by orchestrating formation of distinct decapping complexes. Two Upf1-binding motifs direct the decapping enzyme to nonsense-mediated mRNA decay substrates, a single Edc3-binding motif targets both Edc3 and Dhh1 substrates, and Pat1-binding leucine-rich motifs target Edc3 and Dhh1 substrates under selective conditions. Although it functions as a unique targeting component of specific complexes, Edc3 is a common component of multiple complexes. Scd6 and Xrn1 also have specific binding sites on Dcp2, allowing them to be directly recruited to decapping complexes. Collectively, our results demonstrate that Upf1, Edc3, Scd6, and Pat1 function as regulatory subunits of the holo-decapping enzyme, controlling both its substrate specificity and enzymatic activation.

Biophysical and functional study of CRL5Ozz, a muscle specific ubiquitin ligase complex

Ozz, a member of the SOCS-box family of proteins, is the substrate-binding component of CRL5Ozz, a muscle-specific Cullin-RING ubiquitin ligase complex composed of Elongin B/C, Cullin 5 and Rbx1. CRL5Ozz targets for proteasomal degradation selected pools of substrates, including sarcolemma-associated β-catenin, sarcomeric MyHCemb and Alix/PDCD6IP, which all interact with the actin cytoskeleton. Ubiquitination and degradation of these substrates are required for the remodeling of the contractile sarcomeric apparatus. However, how CRL5Ozz assembles into an active E3 complex and interacts with its substrates remain unexplored. Here, we applied a baculovirus-based expression system to produce large quantities of two subcomplexes, Ozz–EloBC and Cul5–Rbx1. We show that these subcomplexes mixed in a 1:1 ratio reconstitutes a five-components CRL5Ozz monomer and dimer, but that the reconstituted complex interacts with its substrates only as monomer. The in vitro assembled CRL5Ozz complex maintains the capacity to polyubiquitinate each of its substrates, indicating that the protein production method used in these studies is well-suited to generate large amounts of a functional CRL5Ozz. Our findings highlight a mode of assembly of the CRL5Ozz that differs in presence or absence of its cognate substrates and grant further structural studies.

Immune complexes as a tool for strongyloidiasis immunodiagnosis in kidney and liver transplant candidate.

Strongyloidiasis is a chronic and asymptomatic infection in immunocompetent patients. Immunocompromised patients, such as organ transplant candidates, can develop severe forms of this disease, and the best way to prevent progression to these forms is early diagnosis. Serological techniques using specific IgG and immune complexes (IC) detection can help in the diagnosis of these patients. This study aimed to detect specific anti-Strongyloides IC and IgG antibodies in kidney transplant (KT) and liver transplant (LT) candidates. A total of 100 blood samples was collected from transplant candidates (50 blood samples each from KT and LT candidates). Serum was obtained and analysed using enzyme-linked immunosorbent assay for IC and IgG detections. The IC levels showed frequencies of 18% and 2% in the KT and LT groups, respectively, whereas anti-Strongyloides IgG was detected in 34% and 12% of KT and LT candidates, respectively. The correlation between IC and IgG detection is poor in KT candidates, while in LT candidates, there is a significant positive correlation. The detection of IC can be an additional tool for the diagnosis of strongyloidiasis, especially when associated with the detection of specific IgG anti-Strongyloides antibodies.

Phonological patterns in Greek language in toddlers and children with Down syndrome and children with language impairment

Down syndrome is a genetic disorder which is represented by a variety of deficits in all linguistic domains including phonology. Previous research, mainly conducted in the English language, has documented phonological deficits in early childhood in Down syndrome. Given the paucity of research in the area of phonology in the Greek language, the aim of the present study was to evaluate the phonological skills of children with Down syndrome (N = 45) in the Greek language and compare them with those of age‐matched and non‐verbal age children with language impairment (N = 45). A test, standardized in the Greek language, was used for the above purpose which consisted of four subscales: articulation; phonemic analysis; phonemic completion; and phonemic distinction. The results showed that children with Down syndrome performed poorer on all four subscales than children with language impairment, and provided evidence for distinct difficulties in specific consonants and complex articulations inherent in the Greek language.

Metal Ion-Directed Specific DNA Structures and Their Functions.

Various DNA structures, including specific metal ion complexes, have been designed based on the knowledge of canonical base pairing as well as general coordination chemistry. The role of metal ions in these studies is quite broad and diverse. Metal ions can be targets themselves in analytical applications, essential building blocks of certain DNA structures that one wishes to construct, or they can be responsible for signal generation, such as luminescence or redox. Using DNA conjugates with metal chelators, one can more freely design DNA complexes with diverse structures and functions by following the simple HSAB rule. In this short review, the authors summarize a part of their DNA chemistries involving specific metal ion coordination. It consists of three topics: (1) significant stabilization of DNA triple helix by silver ion; (2) metal ion-directed dynamic sequence edition through global conformational change by intramolecular complexation; and (3) reconstruction of luminescent lanthanide complexes on DNA and their analytical applications.

CYP1A1 and CYP1A2 Form Distinct Protein Complexes with NADPH‐cytochrome P450 Reductase, Cytochrome b5, and Heme Oxygenase‐1

The cytosolic face of the endoplasmic reticulum (ER) membrane contains a variety of enzymes involved in oxidative metabolism. Among these, NADPH‐cytochrome P450 reductase (POR) and cytochrome b5 (CYB5) provide reducing electrons necessary for cytochrome P450 (P450) and heme oxygenase‐1 (HO‐1) activity. HO‐1 catalyzes the first and rate‐limiting step in free heme catabolism while the P450s are responsible for the metabolism of endogenous and exogenous compounds, including a majority of prescribed drugs. P450s have been shown to form heteromeric and homomeric complexes with other P450s and these complexes have been associated with alterations in P450 activity. Additionally, the P450 catalytic cycle requires 2 electrons—while POR is able to provide both, CYB5 can provide the second electron in some cases. However, binding of POR and CYB5 to the same P450 has been reported to be mutually exclusive, raising the question of how CYB5 can stimulate P450 activity if POR must dissociate prior to CYB5 binding.In order to shed light on this question, we set out to collect more information on the protein‐protein interaction network that the ER‐membrane proteins participate in. Using bioluminescence resonance energy transfer (BRET), we are able to detect interactions between a pair of proteins and, further, to measure the stability of that pair in the presence of a third protein. To detect protein‐protein interactions, HEK293T cells were co‐transfected with vectors encoding two potentially interacting proteins tagged with either Renilla luciferase (Rluc) or GFP2.While human CYP1A2 showed evidence of a specific complex, with analysis of BRET data showing the presence of homodimers, human CYP1A1 did not form a specific homomeric complex. CYP1A1 and CYP1A2 also differed in how they interacted with other ER membrane proteins. Both proteins showed evidence of heteromeric complex formation with HO‐1, but CYP1A1 only did so in the presence of excess POR. POR and CYB5 do not appear to interact with each other and in the presence of CYP1A2, HO‐1, and several other P450s, a complex between POR and CYB5 was not detected. However, a complex including the two proteins was detected in the presence of CYP1A1 which indicated the presence of a ternary CYB5‐POR‐CYP1A1 complex. The presence of a ternary complex could explain the stimulation of P450 activity by CYB5, though the specific mechanism remains to be determined.

Recent Achievements about Targeted Alpha Therapy-Based Targeting Vectors and Chelating Agents.

One of the most rapidly growing options in the management of cancer therapy is Targeted Alpha Therapy (TAT) through which lethal α-emitting radionuclides conjugated to tumor-targeting vectors selectively deliver high amount of radiation to cancer cells.225Ac, 212Bi, 211At, 213Bi, and 223Ra have been investigated by plenty of clinical trials and preclinical researches for the treatment of smaller tumor burdens, micro-metastatic disease, and post-surgery residual disease. In order to send maximum radiation to tumor cells while minimizing toxicity in normal cells, a high affinity of targeting vectors to cancer tissue is essential. Besides that, the stable and specific complex between chelating agent and α-emitters was found as a crucial parameter. The present review was planned to highlight recent achievements about TAT-based targeting vectors and chelating agents and provide further insight for future researches.

The role of IR‐induced swelling in OPA1‐MICOS interaction in cardiac mitochondria

Mitochondria are membrane‐bound organelles composed of two membranes, the inner mitochondrial membrane (IMM) and the outer mitochondrial membrane (OMM), with the intermembrane space (IMS) localized between them. The IMM is divided into two subcompartments, the inner boundary membrane (IBM) that lies parallel to the OMM, and the cristae membrane (CM), which are IMM invaginations folded into cristae. The IBM and CM are connected at terminals forming circular‐like openings known as cristae junctions (CJs). The structural integrity of the mitochondrial CJs is maintained by the mitochondrial contact site and cristae organizing system (MICOS), a specific protein complex containing several structural and regulatory proteins. The MICOS proteins control the IMM architecture through direct membrane shaping, formation of contact sites, and biogenesis of proteins and lipids. In addition, the optic atrophy 1 (OPA1), a mitochondrial fusion protein, localized also in the CM, has been shown to participate in IMM remodeling which mediates the fusion of the IMM. The structural organization of the IMM is regulated by changes in the matrix volume of mitochondria; excessive matrix swelling in response to energetic and oxidative stress induced by pathological stimuli such as cardiac ischemia‐reperfusion (IR) impairs the integrity of CJs and thereby, alters mitochondrial function. The main goal of this study is to investigate the effects of cardiac IR‐induced swelling on OPA1 and MICOS proteins. Hearts were isolated from male Sprague Dawley rats and perfused with Krebs‐Henseleit solution (KHS) using the Langendorff‐mode technique at a constant flow rate (10‐12 ml/min). The animals were randomly assigned to the following groups: i) perfusion (no ischemia) for 55 min (C‐55 group), ii) ischemia (I group) for 25 min, iii) ischemia in the presence of sanglifehrin A (SfA), an inhibitor of the permeability transition pore (IS), iv) perfusion (no ischemia) for 95 min (C‐95), v) ischemia for 25‐min followed by 40‐min reperfusion (IR group), and vi) IR in the presence of SfA (IRS). SfA (0.5 µM) was present 10 min before ischemia (IS group) and throughout the entire period of reperfusion (IRS group). LDH activity was determined in the coronary effluent as a marker of cell death. At the end of reperfusion, mitochondria were isolated from the hearts by differential centrifugation for analysis of oxygen consumption rates, mitochondrial swelling, and protein levels of long and short forms of OPA1, and MICOS proteins. Our results show that ischemia diminished post‐ischemic recovery of the hearts as evidenced by impaired cardiac contractility, increased LDH activity in the coronary effluent, and reduced mitochondrial respiration. Ischemia alone and IR differently affected the expression of both, OPA1 and mitofilin (Mic‐60, a core MICOS protein) as well as other MICOS components. In conclusion, our data suggest that OPA1 and MICOS proteins are affected differently by ischemia alone and IR.

Associations between moral injury and ICD-11 post-traumatic stress disorder (PTSD) and complex PTSD among help-seeking nurses: a cross-sectional study

ObjectivesThis study aimed to evaluate how moral injury (MI), traumatic experiences and daily stressors were related to the symptoms of post-traumatic stress disorder (PTSD) and International Classification of Diseases 11th...

Learning to Be Elite: Lessons From HIV-1 Controllers and Animal Models on Trained Innate Immunity and Virus Suppression.

Although antiretroviral therapy (ART) has drastically changed the lives of people living with human immunodeficiency virus-1 (HIV-1), long-term treatment has been associated with a vast array of comorbidities. Therefore, a cure for HIV-1 remains the best option to globally eradicate HIV-1/acquired immunodeficiency syndrome (AIDS). However, development of strategies to achieve complete eradication of HIV-1 has been extremely challenging. Thus, the control of HIV-1 replication by the host immune system, namely functional cure, has long been studied as an alternative approach for HIV-1 cure. HIV-1 elite controllers (ECs) are rare individuals who naturally maintain undetectable HIV-1 replication levels in the absence of ART and whose immune repertoire might be a desirable blueprint for a functional cure. While the role(s) played by distinct human leukocyte antigen (HLA) expression and CD8+ T cell responses expressing cognate ligands in controlling HIV-1 has been widely characterized in ECs, the innate immune phenotype has been decidedly understudied. Comparably, in animal models such as HIV-1-infected humanized mice and simian Immunodeficiency Virus (SIV)-infected non-human primates (NHP), viremic control is known to be associated with specific major histocompatibility complex (MHC) alleles and CD8+ T cell activity, but the innate immune response remains incompletely characterized. Notably, recent work demonstrating the existence of trained innate immunity may provide new complementary approaches to achieve an HIV-1 cure. Herein, we review the known characteristics of innate immune responses in ECs and available animal models, identify gaps of knowledge regarding responses by adaptive or trained innate immune cells, and speculate on potential strategies to induce EC-like responses in HIV-1 non-controllers.

Toward passive BCI: asynchronous decoding of neural responses to direction- and angle-specific perturbations during a simulated cockpit scenario

Neuroimaging studies have provided proof that loss of balance evokes specific neural transient wave complexes in electroencephalography (EEG), called perturbation evoked potentials (PEPs). Online decoding of balance perturbations from ongoing EEG signals can establish the possibility of implementing passive brain-computer interfaces (pBCIs) as a part of aviation/driving assistant systems. In this study, we investigated the feasibility of identifying the existence and expression of perturbations in four different conditions by using EEG signals. Fifteen healthy participants experienced four various postural changes while they sat in a glider cockpit. Sudden perturbations were exposed by a robot connected to a glider and moved to the right and left directions with tilting angles of 5 and 10 degrees. Perturbations occurred in an oddball paradigm in which participants were not aware of the time and expression of the perturbations. We employed a hierarchical approach to separate the perturbation and rest, and then discriminate the expression of perturbations. The performance of the BCI system was evaluated by using classification accuracy and F1 score. Asynchronously, we achieved average accuracies of 89.83 and 73.64% and average F1 scores of 0.93 and 0.60 for binary and multiclass classification, respectively. These results manifest the practicality of pBCI for the detection of balance disturbances in a realistic situation.

Application of New Technology of Intelligent Robot Plant Protection in Ecological Agriculture

Crop diseases, pest infestations, water shortages, weed infestations, and other issues affect the agriculture sector. Due to existing agricultural techniques, these issues result in significant crop loss, economic loss, and severe environmental hazards. Because agriculture is such a dynamic industry, robotics cannot solve all of its difficulties; instead, a single solution to a specific complex problem is supplied. To assist with these issues and provide a better approach globally, a variety of systems have been developed. Plant protection robots are characterized by complexity, constraint, and nonlinearity. In order to improve the accuracy and reliability of plant protection robots in agricultural job path planning, we propose a path planning method for agricultural plant protection robots based on a nonlinear algorithm. The ant colony algorithm was selected to plan the path distance index according to the working environment, and the feasibility of the simulation system was calculated. The results show that the fastest time used by the nonlinear algorithm is 5.3, and the path planning accuracy is up to 97.8%. Compared with the traditional algorithm, the algorithm has higher accuracy, less computing time, and higher computing efficiency.

31 Relationship of Mitochondrial Phenotype to Muscle Function and Performance

Abstract Skeletal muscle mitochondria are vital for producing sufficient energy to fuel muscle contractions during exercise. Embedded within the inner mitochondrial membrane are 4 separate protein complexes that are responsible for transferring electrons from specific substrates to the final electron acceptor, oxygen. The proton gradient that is formed from the movement of electrons then drives complex V, synthesizing ATP to fuel cellular work. Recent technological advancements enable exploration beyond simple measures of mitochondria, such as density and overall function, to identify how the organelles produce energy. Specifically, high-resolution respirometry allows investigation into the capacity of each of these mitochondrial protein complexes to determine if they are differentially utilized during specific types of exercise. Further, unique profiles of utilization of these complexes may be hallmarks of success within a certain performance discipline (e.g., racing, dressage, western work, or jumping). In recent years, our laboratory has substantially contributed to progress in this area of research. Under 3 specific scenarios we: 1) defined in horses as young as 6-months-old differential utilization of complexes among breeds destined for certain racing distances; 2) demonstrated differential impacts on specific mitochondrial complexes between submaximal and high-intensity exercise training; and 3) identified a signature of mitochondrial energy production in Thoroughbred racehorses as weanlings that correlates with their race performance later in life. Complex-specific skeletal muscle mitochondrial research in horses is its infancy but has substantial promise to be used as a tool to optimize performance and prevent fatigue-induced injury in performance horses. Further, greater understanding of the inter-relationships of mitochondrial energy production, exercise training, management, and feeding protocols will be crucial to ensure horses realize their peak performance potential and to maintain animal welfare during intense training and competition schedules.

Cavity surface residues of PAD4 and SAG101 contribute to EDS1 dimer signaling specificity in plant immunity.

Arabidopsis pathogen effector-triggered immunity (ETI) is controlled by a family of three lipase-like proteins (EDS1, PAD4, and SAG101) and two subfamilies of HET-S/LOB-B (HeLo)-domain "helper" nucleotide-binding/leucine-rich repeats (ADR1s and NRG1s). EDS1-PAD4 dimers cooperate with ADR1s, and EDS1-SAG101 dimers with NRG1s, in two separate defense-promoting modules. EDS1-PAD4-ADR1 and EDS1-SAG101-NRG1 complexes were detected in immune-activated leaf extracts but the molecular determinants for specific complex formation and function remain unknown. EDS1 signaling is mediated by a C-terminal EP domain (EPD) surface surrounding a cavity formed by the heterodimer. Here we investigated whether the EPDs of PAD4 and SAG101 contribute to EDS1 dimer functions. Using a structure-guided approach, we undertook a comprehensive mutational analysis of Arabidopsis PAD4. We identify two conserved residues (Arg314 and Lys380) lining the PAD4 EPD cavity that are essential for EDS1-PAD4-mediated pathogen resistance, but are dispensable for the PAD4-mediated restriction of green peach aphid infestation. Positionally equivalent Met304 and Arg373 at the SAG101 EPD cavity are required for EDS1-SAG101 promotion of ETI-related cell death. In a PAD4 and SAG101 interactome analysis of ETI-activated tissues, PAD4R314A and SAG101M304R EPD variants maintain interaction with EDS1 but lose association, respectively, with helper nucleotide-binding/leucine-rich repeats ADR1-L1 and NRG1.1, and other immune-related proteins. Our data reveal a fundamental contribution of similar but non-identical PAD4 and SAG101 EPD surfaces to specific EDS1 dimer protein interactions and pathogen immunity.

A nanovaccine for antigen self-presentation and immunosuppression reversal as a personalized cancer immunotherapy strategy.

The strategy of combining a vaccine with immune checkpoint inhibitors has been widely investigated in cancer management, but the complete response rate for this strategy is still unresolved. We describe a genetically engineered cell membrane nanovesicle that integrates antigen self-presentation and immunosuppression reversal (ASPIRE) for cancer immunotherapy. The ASPIRE nanovaccine is derived from recombinant adenovirus-infected dendritic cells in which specific peptide-major histocompatibility complex class I (pMHC-I), anti-PD1 antibody and B7 co-stimulatory molecules are simultaneously anchored by a programmed process. ASPIRE can markedly improve antigen delivery to lymphoid organs and generate broad-spectrum T-cell responses that eliminate established tumours. This work presents a powerful vaccine formula that can directly activate both native T cells and exhausted T cells, and suggests a general strategy for personalized cancer immunotherapy.

QRS complexes and T waves localization in multi-lead ECG signals based on deep learning and electrophysiology knowledge

Accurate locations of key feature points for QRS complexes and T waves in electrocardiograms (ECGs) play a vital role in the analysis of cardiovascular diseases, such as arrhythmia and myocardial infarction. Because accuracy is affected by specific morphological changes of QRS waves and ST-T segments, traditional methods of detecting these waves need to be improved, which depend on empirical parameters and lack of robustness. This paper described a novel QRS complex and T wave localization method based on a U-Net framework combining the convolution neural network and long short-term memory with ensemble learning for multi-lead ECG signals. Using multi-lead ECG as an input, the model extracted strong temporal correlation features and fine morphological features in the training process, and its output was the probability value for every sample point. Dynamic threshold adaptive adjustment strategies during decision-making were then used to locate QRS complexes and T waves. Based on electrophysiology knowledge (EK), this method considered each lead information and was used to reduce missed and false detections. The proposed method based on deep learning and EK was also validated by three public databases. The experimental results indicated that the proposed method achieved a comparable or even better performance, when compared with present state-of-art methods. The currently proposed method produced results with high sensitivity and positive predictive values ranging from 99.45% to 100% for the locations of QRS complex waves, and from 99.99% to 97.88% for the locations of T waves from three datasets. Moreover, definitive analyses for missed and false detections of ECG signals were also used. These signals contained specific QRS complexes and T waves, such as higher amplitude T waves and QRS complexes, which contained fine structures, inverted U waves behind T waves, and waves along with atrial fibrillation and ventricular premature events.

Electromagnetic Fields Generated by the IteraCoil Device Differentiate Mesenchymal Stem Progenitor Cells Into the Osteogenic Lineage.

Rapid advances in mesenchymal stem progenitor cells (MSPCs) have rendered impetus into the area of cell therapy and regenerative medicine. The main promise of future stem cell therapies is their reliance on autologous stem cells derived from adipose tissue, which also includes treatments of bone fractures and degeneration. The effectiveness of different electric devices utilized to reprogram MSPCs toward osteogenic differentiation has provided varying degrees of effectiveness for clinical use. Adipose tissue‐derived MSPCs were flow‐cytometrically characterized and further differentiated into osteoblasts by culturing either in growth medium with pro‐osteogenic supplements or without supplements with alternating electromagnetic field (EMF) generated by IteraCoil. IteraCoil is a multi‐solenoid coil with a specific complex geometry that creates a 3D‐EMF with desired parameters without directly applying electrodes to the cells and tissues. The flow‐cytometric analysis of highly enriched (≥95%) adipose‐derived MSPCs (CD34−, CD73+, CD90+, and CD105+) was utilized for the study. Osteoblasts and chondrocyte differentiations were then assessed by specific staining and quantified using ImageJ (National Institutes of Health). The osteoblastic differentiation of MSPCs cultured in regular medium and exposed to EMF at 0.05 and 1 kHz frequencies was compared with MSPCs cultured in a pro‐osteogenic supplemented medium. In this study, we demonstrated that EMF from IteraCoil might have affected the signaling pathways that induce the osteogenic differentiation of human adipose‐derived MSPCs in the absence of exogenous osteogenic factors. Therefore, EMF‐generated osteogenic differentiation of reprogrammed adipose‐derived autologous MSPCs may treat the loss of osteoblasts and osteoporosis and open new avenues for the development of regenerative cellular therapy. © 2022 Bioelectromagnetics Society.

Phylogenetic and Evolutionary Genomic Analysis of Listeria monocytogenes Clinical Strains in the Framework of Foodborne Listeriosis Risk Assessment.

Listeria monocytogenes is one of the most important foodborne pathogens responsible for listeriosis, a severe disease with symptoms ranging from septicemia, meningoencephalitis, and abortion. Given the strong impact of listeriosis on human health and the difficulty of controlling L. monocytogenes along the food production chain, listeriosis has become a priority subjected to molecular surveillance in European Union/European Economic Area since 2007. From 2018, surveillance is based on whole-genome sequence using the core genome multilocus sequence type. The complete sequences of 132 clinical strains were used to define the evolutionary relatedness among subtypes of L. monocytogenes isolated in Italy from 2010 to 2016, allowing the identification of clades and/or clusters associated with outbreaks or sporadic cases of listeriosis. All the strains analyzed are clustered in lineages I and II, and the majority of the strains were classified as lineage II. A probable epidemic entrance in different years for every clade and cluster from each different region was defined. The persistence of the same specific clonal complexes of L. monocytogenes has been found over long periods; this may be related to the fact that some strains are able to survive better than others in a food production environment. Phylogenic studies, using whole-genome sequence data, are able to identify the emergence of highly persistent pathogenic variants, contributing to improving the hazard characterization of L. monocytogenes.

Lipid tails modulate antimicrobial peptide membrane incorporation and activity.

Membrane disrupting antimicrobial peptides (AMPs) are often amphipathic peptides that interact directly with lipid bilayers. AMPs are generally thought to interact mostly with lipid head groups, but it is less clear how the lipid alkyl chain length and saturation modulate interactions with membranes. Here, we used native mass spectrometry to measure the stoichiometry of three different AMPs-LL-37, indolicidin, and magainin-2-in lipid nanodiscs. We also measured the activity of these AMPs in unilamellar vesicle leakage assays. We found that LL-37 formed specific hexamer complexes but with different intermediates and affinities that depended on the bilayer thickness. LL-37 was also most active in lipid bilayers containing longer, unsaturated lipids. In contrast, indolicidin incorporated to a higher degree into more fluid lipid bilayers but was more active with bilayers with thinner, less fluid lipids. Finally, magainin-2 incorporated to a higher degree into bilayers with longer, unsaturated alkyl chains and showed more activity in these same conditions. Together, these data show that higher amounts of peptide incorporation generally led to higher activity and that AMPs tend to incorporate more into longer unsaturated lipid bilayers. However, the activity of AMPs was not always directly related to amount of peptide incorporated.