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Many signaling processes rely on information decoding at the plasma membrane, and membrane-associated proteins and their complexes are fundamental for regulating this process. Still many questions exist as to how protein complexes are assembled and function at membrane sites to change identity and dynamics of membrane systems. Peripheral membrane proteins containing a calcium and phospholipid-binding C2-domain can act in membrane-related signaling by providing a tethering function so that protein complexes form. C2 domain proteins termed C2-DOMAIN ABSCISIC ACID-RELATED (CAR) proteins are plant-specific, and the functional relevance of this C2 domain protein subgroup is just emerging. The ten Arabidopsis CAR proteins CAR1 to CAR10 have a single C2 domain with a plant-specific insertion, the so-called "CAR-extra-signature" or also termed "sig domain". Via this "sig domain" CAR proteins can bind signaling protein complexes of different kinds and act in biotic and abiotic stress, blue light and iron nutrition. Interestingly, CAR proteins can oligomerize in membrane microdomains, and their presence in the nucleus can be linked with nuclear protein regulation. This shows that CAR proteins may play unprecedented roles in coordinating environmental responses and assembling required protein complexes to transmit information cues between plasma membrane and nucleus. The aim of this review is to summarize structure-function characteristics of the CAR protein family and assemble findings from CAR protein interactions and physiological functions. From this comparative investigation we extract common principles about the molecular operations that CAR proteins may fulfill in the cell. We also deduce functional properties of the CAR protein family based on its evolution and gene expression profiles. We highlight open questions and suggest novel avenues to prove and understand the functional networks and roles played by this protein family in plants.
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Ácido Abscísico , Proteínas de Arabidopsis , Ácido Abscísico/metabolismo , Cálcio/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Transdução de Sinais , Membrana Celular/metabolismoRESUMO
OBJECTIVE: This study aimed to investigate differences in transient endothelial dysfunction (TED) with mental stress in Black and non-Black individuals with coronary heart disease (CHD), and their potential impact on cardiovascular outcomes. METHODS: We examined 812 patients with stable CHD between June 2011 and March 2016 and followed through February 2020 at a university-affiliated hospital network. Flow-mediated vasodilation (FMD) was assessed before and 30 minutes after mental stress. TED was defined as a lower poststress FMD than prestress FMD. We compared prestress FMD, post-stress FMD, and TED between Black and non-Black participants. In both groups, we examined the association of TED with an adjudicated composite end point of cardiovascular death or nonfatal myocardial infarction (first and recurring events) after adjusting for demographic, clinical, and socioeconomic factors. RESULTS: Prestress FMD was lower in Black than non-Black participants (3.7 [2.8] versus 4.9 [3.8], p < .001) and significantly declined with mental stress in both groups. TED occurred more often in Black (76%) than non-Black patients (67%; multivariable-adjusted odds ratio = 1.6, 95% confidence interval = 1.5-1.7). Over a median (interquartile range) follow-up period of 75 (65-82) months, 142 (18%) patients experienced either cardiovascular death or nonfatal myocardial infarction. Black participants had a 41.9% higher risk of the study outcome than non-Black participants (95% confidence interval = 1.01-1.95). TED with mental stress explained 69% of this excess risk. CONCLUSIONS: Among CHD patients, Black individuals are more likely than non-Black individuals to develop endothelial dysfunction with mental stress, which in turn explains a substantial portion of their excess risk of adverse events.
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Doenças Cardiovasculares , Doença das Coronárias , Infarto do Miocárdio , Humanos , Fatores Raciais , Vasodilatação , Infarto do Miocárdio/epidemiologia , Endotélio Vascular , Fatores de Risco , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologiaRESUMO
Cardiovascular risk stratification is a frequent evaluation performed by health professionals. Not uncommonly, requests for risk stratification involve activities or procedures that fall outside of the scope of current evidence-based guidelines. Estimating risk and providing guidance for these requests can be challenging due to limited available evidence. This review focuses on some of these unique requests, each of which are real examples encountered in our practice. We offer guidance by synthesizing the available medical literature and formulating recommendations on topics such as the initiation of testosterone and erectile dysfunction therapy, SCUBA and skydiving, polygraphy, and electroconvulsive therapy.
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Doenças Cardiovasculares , Disfunção Erétil , Masculino , Humanos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Fatores de Risco , Testosterona/uso terapêutico , Fatores de Risco de Doenças Cardíacas , Medição de RiscoRESUMO
Introduction: Pro-thrombotic events are one of the prevalent causes of intensive care unit (ICU) admissions among COVID-19 patients, although the signaling events in the stimulated platelets are still unclear. Methods: We conducted a comparative analysis of platelet transcriptome data from healthy donors, ICU, and non-ICU COVID-19 patients to elucidate these mechanisms. To surpass previous analyses, we constructed models of involved networks and control cascades by integrating a global human signaling network with transcriptome data. We investigated the control of platelet hyperactivation and the specific proteins involved. Results: Our study revealed that control of the platelet network in ICU patients is significantly higher than in non-ICU patients. Non-ICU patients require control over fewer proteins for managing platelet hyperactivity compared to ICU patients. Identification of indispensable proteins highlighted key subnetworks, that are targetable for system control in COVID-19-related platelet hyperactivity. We scrutinized FDA-approved drugs targeting indispensable proteins and identified fostamatinib as a potent candidate for preventing thrombosis in COVID-19 patients. Discussion: Our findings shed light on how SARS-CoV-2 efficiently affects host platelets by targeting indispensable and critical proteins involved in the control of platelet activity. We evaluated several drugs for specific control of platelet hyperactivity in ICU patients suffering from platelet hyperactivation. The focus of our approach is repurposing existing drugs for optimal control over the signaling network responsible for platelet hyperactivity in COVID-19 patients. Our study offers specific pharmacological recommendations, with drug prioritization tailored to the distinct network states observed in each patient condition. Interactive networks and detailed results can be accessed at https://fostamatinib.bioinfo-wuerz.eu/.
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COVID-19 , Humanos , SARS-CoV-2 , Cuidados Críticos , Aminopiridinas , Oxazinas , PiridinasRESUMO
Background: Cardiac amyloidosis can coexist in patients with severe aortic stenosis. There are limited outcomes data on whether this impacts the risk of transcatheter aortic valve replacement (TAVR). Objectives: The authors aimed to investigate the effect of amyloidosis on outcomes of TAVR. Methods: We used the Nationwide Readmissions Database to identify hospitalizations for TAVR between 2016 and 2019. The presence of a diagnosis of amyloidosis was identified. Propensity score-weighted regression analysis was used to identify the association of amyloidosis with in-hospital mortality, acute ischemic stroke, and 30-day readmission rate after TAVR. Results: We identified 245,020 hospitalizations for TAVR, including 273 in patients with amyloidosis. The mean age was 79.4 ± 8.4 years. There was no difference in in-hospital mortality or 30-day readmission rate in patients with and without amyloidosis (1.8% vs 1.5%, P = 0.622; and 12.9% vs 12.5%, P = 0.858; respectively). However, there was a higher rate of acute ischemic stroke in patients with amyloidosis (6.2% vs 1.8%, P < 0.001). Propensity score-weighted logistic regression analysis showed the presence of amyloidosis was associated with greater odds of acute ischemic stroke (odds ratio: 3.08, 95% CI: 1.41-6.71, P = 0.005), but no difference in mortality (odds ratio: 0.79, 95% CI: 0.28-2.27, P = 0.666) or 30-day readmission rate after TAVR (HR: 0.72, 95% CI: 0.41-1.25, P = 0.241). Conclusions: This analysis suggests amyloidosis may be associated with a higher thromboembolic risk after TAVR that merits further investigation.
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Candida auris is a globally emerging fungal pathogen responsible for causing nosocomial outbreaks in healthcare associated settings. It is known to cause infection in all age groups and exhibits multi-drug resistance with high potential for horizontal transmission. Because of this reason combined with limited therapeutic choices available, C. auris infection has been acknowledged as a potential risk for causing a future pandemic, and thus seeking a promising strategy for its treatment is imperative. Here, we combined evolutionary information with reverse vaccinology approach to identify novel epitopes for vaccine design that could elicit CD4+ T-cell responses against C. auris. To this end, we extensively scanned the family of proteins encoded by C. auris genome. In addition, a pathogen may acquire substitutions in epitopes over a period of time which could cause its escape from the immune response thus rendering the vaccine ineffective. To lower this possibility in our design, we eliminated all rapidly evolving genes of C. auris with positive selection. We further employed highly conserved regions of multiple C. auris strains and identified two immunogenic and antigenic T-cell epitopes that could generate the most effective immune response against C. auris. The antigenicity scores of our predicted vaccine candidates were calculated as 0.85 and 1.88 where 0.5 is the threshold for prediction of fungal antigenic sequences. Based on our results, we conclude that our vaccine candidates have the potential to be successfully employed for the treatment of C. auris infection. However, in vivo experiments are imperative to further demonstrate the efficacy of our design.
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Biological networks are characterized by diverse interactions and dynamics in time and space. Many regulatory modules operate in parallel and are interconnected with each other. Some pathways are functionally known and annotated accordingly, e.g., endocytosis, migration, or cytoskeletal rearrangement. However, many interactions are not so well characterized. For reconstructing the biological complexity in cellular networks, we combine here existing experimentally confirmed and analyzed interactions with a protein-interaction inference framework using as basis experimentally confirmed interactions from other organisms. Prediction scoring includes sequence similarity, evolutionary conservation of interactions, the coexistence of interactions in the same pathway, orthology as well as structure similarity to rank and compare inferred interactions. We exemplify our inference method by studying host-pathogen interactions during infection of Mus musculus (phagolysosomes in alveolar macrophages) with Aspergillus fumigatus (conidia, airborne, asexual spores). Three of nine predicted critical host-pathogen interactions could even be confirmed by direct experiments. Moreover, we suggest drugs that manipulate the host-pathogen interaction.
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After the recent emergence of SARS-CoV-2 infection, unanswered questions remain related to its evolutionary history, path of transmission or divergence and role of recombination. There is emerging evidence on amino acid substitutions occurring in key residues of the receptor-binding domain of the spike glycoprotein in coronavirus isolates from bat and pangolins. In this article, we summarize our current knowledge on the origin of SARS-CoV-2. We also analyze the host ACE2-interacting residues of the receptor-binding domain of spike glycoprotein in SARS-CoV-2 isolates from bats, and compare it to pangolin SARS-CoV-2 isolates collected from Guangdong province (GD Pangolin-CoV) and Guangxi autonomous regions (GX Pangolin-CoV) of South China. Based on our comparative analysis, we support the view that the Guangdong Pangolins are the intermediate hosts that adapted the SARS-CoV-2 and represented a significant evolutionary link in the path of transmission of SARS-CoV-2 virus. We also discuss the role of intermediate hosts in the origin of Omicron.
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COVID-19 , Quirópteros , Animais , China , Pangolins/genética , Filogenia , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
Pre-ejection period (PEP), an indicator of sympathetic nervous system activity, is useful in psychophysiology and cardiovascular studies. Accurate PEP measurement is challenging and relies on robust identification of the timing of aortic valve opening, marked as the B point on impedance cardiogram (ICG) signals. The ICG sensitivity to noise and its waveform's morphological variability makes automated B point detection difficult, requiring inefficient and cumbersome expert visual annotation. In this article, we propose a machine learning-based automated algorithm to detect the aortic valve opening for PEP measurement, which is robust against noise and ICG morphological variations. We analyzed over 60 hr of synchronized ECG and ICG records from 189 subjects. A total of 3657 averaged beats were formed using our recently developed ICG noise removal algorithm. Features such as the averaged ICG waveform, its first and second derivatives, as well as high-level morphological and critical hemodynamic parameters were extracted and fed into the regression algorithms to estimate the B point location. The morphological features were extracted from our proposed "variable" physiologically valid search-window related to diverse B point shapes. A subject-wise nested cross-validation procedure was performed for parameter tuning and model assessment. After examining multiple regression models, Adaboost was selected, which demonstrated superior performance and higher robustness to five state-of-the-art algorithms that were evaluated in terms of low mean absolute error of 3.5 ms, low median absolute error of 0.0 ms, high correlation with experts' estimates (Pearson coefficient = 0.9), and low standard deviation of errors of 9.2 ms. For reproducibility, an open-source toolbox is provided.
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Valva Aórtica , Cardiografia de Impedância , Humanos , Cardiografia de Impedância/métodos , Valva Aórtica/fisiologia , Impedância Elétrica , Reprodutibilidade dos Testes , AlgoritmosRESUMO
PURPOSE OF REVIEW: Wearable technology is rapidly evolving and the data that it can provide regarding an individual's health is becoming increasingly important for clinicians to consider. The purpose of this review is to help inform health care providers of the benefits of smartwatch interrogation, with a focus on reviewing the various parameters and how to apply the data in a meaningful way. RECENT FINDINGS: This review details interpretation of various parameters found commonly in newer smartwatches such as heart rate, step count, ECG, heart rate recovery (HRR), and heart rate variability (HRV), while also discussing potential pitfalls that a clinician should be aware of. Smartwatch interrogation is becoming increasingly relevant as the continuous data it provides helps health care providers make more informed decisions regarding diagnosis and treatment. For this reason, we recommend health care providers familiarize themselves with the technology and integrate it into clinical practice.
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Dispositivos Eletrônicos Vestíveis , Eletrocardiografia/instrumentação , Eletrocardiografia/métodos , Teste de Esforço/instrumentação , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , HumanosRESUMO
BACKGROUND: Handheld ultrasound devices are increasingly used by clinicians for their ease of use and portability. Their utility for estimating right atrial pressure (RAP) is poorly described. METHODS: This prospective study enrolled 50 consecutive patients presenting for outpatient right heart catheterization (RHC). A handheld ultrasound device was used to measure inferior vena cava size and collapsibility and estimate RAP to be 3, 8, or 15 mmHg according to American Society of Echocardiography recommendations for cardiac chamber quantification. Invasive pressure measurements were then performed using RHC. Spearman's correlation and linear regression analysis were used to evaluate the association between estimated RAP using ultrasound and invasive RAP. RESULTS: Fifty patients were enrolled (mean age 68 ± 8 years). Estimated RAP by ultrasound was significantly associated with invasive RAP (r 0.80; R2 0.63; 95% confidence interval, 0.61-0.96; P < .001). The correlation was stronger when RHC was indicated for evaluation of heart failure (r 0.88; P < .001) compared with other indications (r 0.69; P < .001). An estimated RAP of 3, 8, and 15 mmHg by ultrasound had a sensitivity and specificity of predicting an invasive RAP of 0-5, 6-10, and > 10 mmHg of 88% and 76%, 56% and 88%, and 81% and 97%, respectively, with overall accuracy of 80%, 76%, and 92%, respectively. Estimated RAP also correlated with invasive pulmonary capillary wedge pressure (r 0.64; R2 0.41; 95% confidence interval, 0.26-0.54; P < .001). CONCLUSIONS: Handheld ultrasonography is a useful tool that can accurately estimate RAP at the bedside.
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Função do Átrio Direito , Pressão Atrial , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Ecocardiografia , Cateterismo CardíacoRESUMO
Parkinson's disease (PD) is a multifactorial ailment that severely affects the viability of dopaminergic neurons leading to progressive loss of motor control. The current regimen for PD treatment includes synthetic drugs that lack efficacy and cause serious side effects. Consequently, recent drug development studies are focusing on alternative medicines from plant sources. Artemisia pallens Wall. ex DC, commonly known as davana, is an annual aromatic herb cultivated in southern India. Given the diverse traditional and scientifically documented therapeutic effects of A. pallens, the pharmacological potential of the isolates of the plant, namely bicyclogermacrene (D1), cis-davanone (D3), and cis-hydroxy davanone (D5), was tested for anti-Parkinson's activity in Caenorhabditis elegans model. The tested compounds alleviated α-synuclein (α-syn) aggregation and maximum decline was observed in 25 µM D1 supplemented worms. Additionally, D1 modulated dopamine regulated nonanol-1 repulsion and locomotory behaviour of C. elegans validating its future use as a dopamine-enhancing agent. The genetic regulation mediating the above effects validated through the qPCR study showed that D1 supplementation displayed its anti-Parkinson's effect through upregulation of the antioxidant defence system genes (superoxide dismutase (sod)-1, sod-2, and sod-4) and PD associated pdr-1 gene that maintains the mitochondrial proteostasis. The molecular docking studies of C. elegans PDR-1 with D1 further confirmed its contribution in D1 induced abridgment of Parkinson disease linked pathologies in C. elegans disease model. Hence, this article proposes D1 as an effective regimen for curtailing the Parkinson disease linked pathologies through mechanism of maintaining cellular redox state and proteostasis.
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Artemisia , Proteínas de Caenorhabditis elegans , Doença de Parkinson , Transtornos Parkinsonianos , Sesquiterpenos , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Modelos Animais de Doenças , Dopamina/farmacologia , Neurônios Dopaminérgicos/patologia , Simulação de Acoplamento Molecular , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/patologia , Sesquiterpenos/farmacologia , Superóxido Dismutase/farmacologia , alfa-Sinucleína/genética , alfa-Sinucleína/farmacologiaRESUMO
Pre-ejection period (PEP) is an index of sympathetic nervous system activity that can be computed from electrocardiogram (ECG) and impedance cardiogram (ICG) signals, but sensitive to speech/motion artifact. We sought to validate an ICG noise removal method, three-stage ensemble-average algorithm (TEA), in data acquired from a clinical trial comparing active versus sham non-invasive vagal nerve stimulation (tcVNS) after standardized speech stress. We first compared TEA's performance versus the standard conventional ensemble-average algorithm (CEA) approach to classify noisy ICG segments. We then analyzed ECG and ICG data to measure PEP and compared group-level differences in stress states with each approach. We evaluated 45 individuals, of whom 23 had post-traumatic stress disorder (PTSD). We found that the TEA approach identified artifact-corrupted beats with intraclass correlation coefficient > 0.99 compared to expert adjudication. TEA also resulted in higher group-level differences in PEP between stress states than CEA. PEP values were lower in the speech stress (vs. baseline rest) group using both techniques, but the differences were greater using TEA (12.1 ms) than CEA (8.0 ms). PEP differences in groups divided by PTSD status and tcVNS (active vs. sham) were also greater when using the TEA versus CEA method, although the magnitude of the differences was lower. In conclusion, TEA helps to accurately identify noisy ICG beats during speaking stress, and this increased accuracy improves sensitivity to group-level differences in stress states compared to CEA, suggesting greater clinical utility.
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Antígeno Carcinoembrionário , Cardiografia de Impedância , Algoritmos , Artefatos , Cardiografia de Impedância/métodos , Eletrocardiografia , HumanosRESUMO
Filovirus ebolavirus (ZE; Zaire ebolavirus, Bundibugyo ebolavirus), Neisseria meningitidis (NM), and Trypanosoma brucei (Tb) are serious infectious pathogens, spanning viruses, bacteria and protists and all may target the blood and central nervous system during their life cycle. NM and Tb are extracellular pathogens while ZE is obligatory intracellular, targetting immune privileged sites. By using interactomics and comparative evolutionary analysis we studied whether conserved human proteins are targeted by these pathogens. We examined 2797 unique pathogen-targeted human proteins. The information derived from orthology searches of experimentally validated protein-protein interactions (PPIs) resulted both in unique and shared PPIs for each pathogen. Comparing and analyzing conserved and pathogen-specific infection pathways for NM, TB and ZE, we identified human proteins predicted to be targeted in at least two of the compared host-pathogen networks. However, four proteins were common to all three host-pathogen interactomes: the elongation factor 1-alpha 1 (EEF1A1), the SWI/SNF complex subunit SMARCC2 (matrix-associated actin-dependent regulator of chromatin subfamily C), the dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit 1 (RPN1), and the tubulin beta-5 chain (TUBB). These four human proteins all are also involved in cytoskeleton and its regulation and are often addressed by various human pathogens. Specifically, we found (i) 56 human pathogenic bacteria and viruses that target these four proteins, (ii) the well researched new pandemic pathogen SARS-CoV-2 targets two of these four human proteins and (iii) nine human pathogenic fungi (yet another evolutionary distant organism group) target three of the conserved proteins by 130 high confidence interactions.
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Animal health issues are important for farming community in agriculture. Small ruminant populations such as goats and sheep often get affected with contagious diseases. Peste des petits ruminants caused by a virus which need to be detected quickly to isolate affected animals and stop the spread of disease. The H protein of Peste des petits ruminants virus has sialic acid specific receptor, therefore sialic acid reduce and stabilized gold-nanoparticles were synthesize by a simple one pot method and without chemically modifying the sialic acid. The gold nanoparticles showed targetspecific aggregation with viral particles via hemagglutinin-sialic acid binding. The PPR virus was readily detected at the dilution of 10-6 by sialic acid-AuNPs. While comparing with the standard monoclonal antibody based test used for the detection of Peste des petits ruminants virus, sialic acid-AuNPs gave detection faster in less than 2 minute.
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Doenças das Cabras , Nanopartículas Metálicas , Peste dos Pequenos Ruminantes , Vírus da Peste dos Pequenos Ruminantes , Animais , Doenças das Cabras/diagnóstico , Ouro , Indicadores e Reagentes , Ácido N-Acetilneuramínico , Peste dos Pequenos Ruminantes/diagnóstico , OvinosRESUMO
A viral infection involves entry and replication of viral nucleic acid in a host organism, subsequently leading to biochemical and structural alterations in the host cell. In the case of SARS-CoV-2 viral infection, over-activation of the host immune system may lead to lung damage. Albeit the regeneration and fibrotic repair processes being the two protective host responses, prolonged injury may lead to excessive fibrosis, a pathological state that can result in lung collapse. In this review, we discuss regeneration and fibrosis processes in response to SARS-CoV-2 and provide our viewpoint on the triggering of alveolar regeneration in coronavirus disease 2019 (COVID-19) patients.
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COVID-19/patologia , Pulmão/fisiologia , Regeneração , COVID-19/virologia , Epigenômica , Fibrose , Humanos , Sistema Imunitário/metabolismo , MicroRNAs/metabolismo , SARS-CoV-2/isolamento & purificação , Transdução de SinaisRESUMO
Aspergillus is an important fungal genus containing economically important species, as well as pathogenic species of animals and plants. Using eighteen fungal species of the genus Aspergillus, we conducted a comprehensive investigation of conserved genes and their evolution. This also allows us to investigate the selection pressure driving the adaptive evolution in the pathogenic species A. fumigatus. Among single-copy orthologs (SCOs) for A. fumigatus and the closely related species A. fischeri, we identified 122 versus 50 positively selected genes (PSGs), respectively. Moreover, twenty conserved genes of unknown function were established to be positively selected and thus important for adaption. A. fumigatus PSGs interacting with human host proteins show over-representation of adaptive, symbiosis-related, immunomodulatory and virulence-related pathways, such as the TGF-ß pathway, insulin receptor signaling, IL1 pathway and interfering with phagosomal GTPase signaling. Additionally, among the virulence factor coding genes, secretory and membrane protein-coding genes in multi-copy gene families, 212 genes underwent positive selection and also suggest increased adaptation, such as fungal immune evasion mechanisms (aspf2), siderophore biosynthesis (sidD), fumarylalanine production (sidE), stress tolerance (atfA) and thermotolerance (sodA). These genes presumably contribute to host adaptation strategies. Genes for the biosynthesis of gliotoxin are shared among all the close relatives of A. fumigatus as an ancient defense mechanism. Positive selection plays a crucial role in the adaptive evolution of A. fumigatus. The genome-wide profile of PSGs provides valuable targets for further research on the mechanisms of immune evasion, antimycotic targeting and understanding fundamental virulence processes.
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OBJECTIVE: We propose a MATLAB-based tool to convert electrocardiography (ECG) waveforms from paper-based ECG records into digitized ECG signals that is vendor-agnostic. The tool is packaged as an open source standalone graphical user interface (GUI) based application. METHODS AND PROCEDURES: To reach this objective we: (1) preprocess the ECG records, which includes skew correction, background grid removal and linear filtering; (2) segment ECG signals using Connected Components Analysis (CCA); (3) implement Optical Character Recognition (OCR) for removal of overlapping ECG lead characters and for interfacing of patients' demographic information with their research records or their electronic medical record (EMR). The ECG digitization results are validated through a reader study where clinically salient features, such as intervals of QRST complex, between the paper ECG records and the digitized ECG records are compared. RESULTS: Comparison of clinically important features between the paper-based ECG records and the digitized ECG signals, reveals intra- and inter-observer correlations of 0.86-0.99 and 0.79-0.94, respectively. The kappa statistic was found to average at 0.86 and 0.72 for intra- and inter-observer correlations, respectively. CONCLUSION: The clinically salient features of the ECG waveforms such as the intervals of QRST complex, are preserved during the digitization procedure. Clinical and Healthcare Impact: This open-source digitization tool can be used as a research resource to digitize paper ECG records thereby enabling development of new prediction algorithms to risk stratify individuals with cardiovascular disease, and/or allow for development of ECG-based cardiovascular diagnoses relying upon automated digital algorithms.
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Eletrocardiografia , Processamento de Sinais Assistido por Computador , Algoritmos , Registros Eletrônicos de Saúde , HumanosRESUMO
Matrix Metalloproteinases (MMPs)-induced altered proteolysis of extracellular matrix proteins and basement membrane holds the key for tumor progression and metastasis. Matrix metalloproteinases-7 (Matrilysin), the smallest member of the MMP family also performs quite alike; thus serves as a potential candidate for anti-tumor immunotherapy. Conversely, being an endogenous tumor-associated antigen (TAA), targeting MMP-7 for immunization is challenging. But MMP-7-based xenovaccine can surmount the obstacle of poor immunogenicity and immunological tolerance, often encountered in TAA-based conventional vaccine for anti-tumor immunotherapy. This paves the way for investigating the potential of MMP-7-derived major histocompatibility complex (MHC)-binding peptides to elicit precise epitope-specific T-cell responses towards their possible inclusion in anti-tumor vaccine formulations. Perhaps it also ushers the path of achieving multiple epitope-based broad and universal cellular immunity. In current experiment, an immunoinformatics approach has been employed to identify the putative canine matrix matelloproteinases-7 (cMMP-7)-derived peptides with MHC class-I-binding motifs which can elicit potent antigen-specific immune responses in BALB/c mice. Immunization with the cMMP-7 DNA vaccine induced a strong CD8+ cytotoxic T lymphocytes (CTLs) and Th1- type response, with high level of gamma interferon (IFN-γ) production in BALB/c mice. The two identified putative MHC-I-binding nonameric peptides (Peptide32-40 and Peptide175-183) from cMMP-7 induced significant lymphocyte proliferation along with the production of IFN-γ from CD8+ T-cells in mice immunized with cMMP-7 DNA vaccine. The current observation has depicted the immunogenic potential of the two cMMP-7-derived nonapeptides for their possible exploitation in xenovaccine-mediated anti-tumor immunotherapy in mouse model.