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The recently discovered methodologies to cultivate and genetically manipulate Treponema pallidum subsp. pallidum (T. pallidum) have significantly helped syphilis research, allowing the in vitro evaluation of antibiotic efficacy, performance of controlled studies to assess differential treponemal gene expression, and generation of loss-of-function mutants to evaluate the contribution of specific genetic loci to T. pallidum virulence. Building on this progress, we engineered the T. pallidum SS14 strain to express a red-shifted green fluorescent protein (GFP) and Sf1Ep cells to express mCherry and blue fluorescent protein (BFP) for enhanced visualization. These new resources improve microscopy- and cell sorting-based applications for T. pallidum, better capturing the physical interaction between the host and pathogen, among other possibilities. Continued efforts to develop and share new tools and resources are required to help our overall knowledge of T. pallidum biology and syphilis pathogenesis reach that of other bacterial pathogens, including spirochetes.
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Proteínas Luminescentes , Sífilis , Treponema pallidum , Treponema pallidum/genética , Sífilis/microbiologia , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Humanos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteína Vermelha Fluorescente , Virulência/genética , TreponemaRESUMO
The advent of the so-called colorful biology era is in line with the discovery of fluorescent proteins (FPs), which can be widely used to detect the intracellular locations of macromolecules or to determine the abundance of metabolites in organelles. The application of multiple FPs that emit different spectra and colors could be implemented to precisely evaluate cellular events. FPs were initially established with the emergence of the green fluorescent protein (GFP) from jellyfish. Red fluorescent proteins (RFPs) from marine anemones and several corals adopt fluorescent chromophores that are similar to GFP. Chromophores of GFP and GFP-like FPs are formed through the oxidative rearrangement of three chromophore-forming residues, thereby limiting their application to only oxidative environments. Alternatively, some proteins can be fluorescent upon their interaction with cellular prosthetic cofactors and, thus, work in aerobic and anaerobic conditions. The modification of an NADPH-dependent blue fluorescent protein (BFP) also expanded its application to the quantization of NADPH in the cellular environment. However, cofactor-dependent BFPs have an intrinsic weakness of poor photostability with a high fluorescent background. This review explores GFP-derived and NADPH-dependent BFPs with a focus on NADPH-dependent BFPs, which might be technically feasible in the near future upon coupling with two-photon fluorescence microscopy or nucleic acid-mimickers. KEY POINTS: ⢠Oxidation-dependent GFP-like BFPs and redox-free NADPH-dependent BFPs ⢠GFPs of weak photostability and intensity with a high fluorescent background ⢠Real-time imaging using mBFP under two-photon fluorescence microscopy.
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Antozoários , Fenilpropionatos , Animais , NADP , Proteínas de Fluorescência Verde/genética , CorantesRESUMO
The rapid advancement in AI requires efficient accelerators for training on edge devices, which often face challenges related to the high hardware costs of floating-point arithmetic operations. To tackle these problems, efficient floating-point formats inspired by block floating-point (BFP), such as Microsoft Floating Point (MSFP) and FlexBlock (FB), are emerging. However, they have limited dynamic range and precision for the smaller magnitude values within a block due to the shared exponent. This limits the BFP's ability to train deep neural networks (DNNs) with diverse datasets. This paper introduces the hybrid precision (HPFP) selection algorithms, designed to systematically reduce precision and implement hybrid precision strategies, thereby balancing layer-wise arithmetic operations and data path precision to address the shortcomings of traditional floating-point formats. Reducing the data bit width with HPFP allows more read/write operations from memory per cycle, thereby decreasing off-chip data access and the size of on-chip memories. Unlike traditional reduced precision formats that use BFP for calculating partial sums and accumulating those partial sums in 32-bit Floating Point (FP32), HPFP leads to significant hardware savings by performing all multiply and accumulate operations in reduced floating-point format. For evaluation, two training accelerators for the YOLOv2-Tiny model were developed, employing distinct mixed precision strategies, and their performance was benchmarked against an accelerator utilizing a conventional brain floating point of 16 bits (Bfloat16). The HPFP selection, employing 10 bits for the data path of all layers and for the arithmetic of layers requiring low precision, along with 12 bits for layers requiring higher precision, results in a 49.4% reduction in energy consumption and a 37.5% decrease in memory access. This is achieved with only a marginal mean Average Precision (mAP) degradation of 0.8% when compared to an accelerator based on Bfloat16. This comparison demonstrates that the proposed accelerator based on HPFP can be an efficient approach to designing compact and low-power accelerators without sacrificing accuracy.
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Manipulation of multiple genes to engineer Chinese Hamster Ovary (CHO) cells for better performance in production processes of biopharmaceuticals has recently become more and more popular. Yet, identification of useful genes and the unequivocally assessment of their effect alone and in combination(s) on the cellular phenotype is difficult due to high variation between subclones. Here, we present development and proof-of-concept of a novel engineering strategy using multiplexable activation of artificially repressed genes (MAARGE). This strategy will allow faster screening of overexpression of multiple genes in all possible combinations. MAARGE, in its here presented installment, comprises four different genes of interest that can all be stably integrated into the genome from one plasmid in a single transfection. Three of the genes are initially repressed by a repressor element (RE) that is integrated between promoter and translation start site. We show that an elongated 5'-UTR with an additional transcription termination (poly(A)) signal most efficiently represses protein expression. Distinct guide RNA (gRNA) targets flanking the REs for each gene then allow to specifically delete the RE by CRISPR/Cas9 and thus to activate the expression of the corresponding gene(s). We show that both individual and multiplexed activation of the genes of interest in a stably transfected CHO cell line is possible. Also, upon transfection of this stable cell line with all three gRNAs together, it was possible to isolate cells that express all potential gene combinations in a single experiment.
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Sistemas CRISPR-Cas , Expressão Gênica , Engenharia Genética/métodos , Animais , Células CHO , Cricetinae , Cricetulus , Plasmídeos/genética , Plasmídeos/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , TransfecçãoRESUMO
This study reports the effects of exposing cells of the prototypical enteropathogenic Escherichia coli (EPEC) strain E2348/69 to static magnetic fields (SMF) of varying intensities to observe their capacity to autoaggregate and the effect on cell adherence. The results showed that bacteria exposure over the course of 5 min to an intensity of 53 mT reduced autoaggregation by 28%. However, with intensities of up to 100 mT with the same exposure time, bacteria autoaggregation was reduced by approximately 50%; and after 30 min at the same intensity, it was indistinguishable from that observed in a non-autoaggregative strain. Furthermore, it was observed that SMF treatment also modified the typical localized adherence pattern of EPEC E2348/69. The observed effects are not related to bacteria damage. The above was confirmed because, after a 107 mT SMF treatment over the course of 30 min, cell viability and membrane permeability were the same to that observed in untreated controls. The obtained results suggest that the SMF effect on the E2348/69 EPEC strain alters the expression of the bundle-forming pilus (BFP), due to the fact that the same strain without the EPEC adherence factor plasmid that encodes the BFP operon was unable to autoaggregate. Electron microscopic analyses revealed structural differences between cells exposed to SMF with respect to untreated controls. In conclusion, the SMF treatment of 107 mT for 30 min reduced EPEC E2348/69 autoaggregation and modified its adherence pattern, with both events likely being associated with changes in BFP expression. Bioelectromagnetics. 38:570-578, 2017. © 2017 Wiley Periodicals, Inc.
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Escherichia coli Enteropatogênica , Campos Magnéticos , Aderência Bacteriana , Linhagem Celular , Permeabilidade da Membrana Celular , Escherichia coli Enteropatogênica/citologia , HumanosRESUMO
Bacteroides fragilis as a commensal bacterium is a member of the human intestinal flora, but as an opportunistic pathogen it can cause serious infections as well. Some of them, harbouring an enterotoxin gene (bft), may cause diarrhoea mainly in young children. Recently it has been shown that a member of C11 proteases called fragipain (fpn) can activate the enterotoxin, while C10 protease (bfp) is suspected of playing an important role in the invasiveness of the B. fragilis isolates. The objective of this study was to investigate the prevalence and distribution of the bft isotypes in 200 Hungarian B. fragilis isolates collected recently; and in a subset of 72 strains, we wanted to determine the prevalence of bfp1-4 and fpn genes in bft-positive and bft-negative strains. Using the MALDI-TOF MS cfiA identification project file, 19 B. fragilis strains belonging to Division II were identified and the presence of the cfiA gene was confirmed by RT-PCR. Twenty six (13.0%) B. fragilis isolates turned out to be bft gene positive by RT-PCR; 20 isolates harboured bft-1 and six bft-2 isotypes, but no bft-3 isotype containing strains were found. A melting curve analysis and the PCR-RFLP were performed to differentiate between the bft-1 and bft-2 isotypes confirmed by sequencing. Thirty eight strains harboured bfp1, 58 isolates contained bfp2 gene, while 17 isolates proved positive for bfp3. Morever, no bfp4 positive isolate was found, and some of the B. fragilis strains tested harboured two or three bfp isotypes simultaneously. Among the 26 bft-positive strains, 24 contained the fpn gene, which confirms the role of fragipain in the activation of B. fragilis enterotoxin. In experiments, a significant negative correlation between fpn and cfiA was demonstrated (p < 0.000), a positive correlation was found between bfp2 and fpn genes (p = 0.0000803), and a negative correlation between bfp2 and cfiA genes (p = 0.011).
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Toxinas Bacterianas/genética , Bacteroides fragilis/genética , Cisteína Proteases/genética , Enterotoxinas/genética , Metaloendopeptidases/genética , Bacteroides fragilis/isolamento & purificação , Bacteroides fragilis/patogenicidade , Microbioma Gastrointestinal/genética , Humanos , Hungria , Isoformas de Proteínas/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
BACKGROUND: Recombinant protein production in the methylotrophic yeast Pichia pastoris largely relies on integrative vectors. Although the stability of integrated expression cassettes is well appreciated for most applications, the availability of reliable episomal vectors for this host would represent a useful tool to expedite cloning and high-throughput screening, ameliorating also the relatively high clonal variability reported in transformants from integrative vectors caused by off-target integration in the P. pastoris genome. Recently, heterologous and endogenous autonomously replicating sequences (ARS) were identified in P. pastoris by genome mining, opening the possibility of expanding the available toolbox to include efficient episomal plasmids. The aim of this technical report is to validate a 452-bp sequence ("panARS") in context of P. pastoris expression vectors, and to compare their performance to classical integrative plasmids. Moreover, we aimed to test if such episomal vectors would be suitable to sustain in vivo recombination, using fragments for transformation, directly in P. pastoris cells. RESULTS: A panARS-based episomal vector was evaluated using blue fluorescent protein (BFP) as a reporter gene. Normalized fluorescence from colonies carrying panARS-BFP outperformed the level of signal obtained from integrative controls by several-fold, whereas endogenous sequences, identified from the P. pastoris genome, were not as efficient in terms of protein production. At the single cell level, panARS-BFP clones showed lower interclonal variability but higher intraclonal variation compared to their integrative counterparts, supporting the idea that heterologous protein production could benefit from episomal plasmids. Finally, efficiency of 2-fragment and 3-fragment in vivo recombination was tested using varying lengths of overlapping regions and molar ratios between fragments. Upon optimization, minimal background was obtained for in vivo assembled vectors, suggesting this could be a quick and efficient method to generate of episomal plasmids of interest. CONCLUSIONS: An expression vector based on the panARS sequence was shown to outperform its integrative counterparts in terms of protein productivity and interclonal variability, facilitating recombinant protein expression and screening. Using optimized fragment lengths and ratios, it was possible to perform reliable in vivo recombination of fragments in P. pastoris. Taken together, these results support the applicability of panARS episomal vectors for synthetic biology approaches.
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Vetores Genéticos , Pichia/genética , Plasmídeos , Proteínas Recombinantes/biossíntese , Recombinação Genética , Clonagem Molecular , Regulação Fúngica da Expressão Gênica , Metanol/metabolismo , Pichia/metabolismo , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Biologia Sintética/métodosRESUMO
Jasmonic acid (JA) is a crucial phytohormone that regulates plant immunity. The endogenous JA level is determined by the rates of its biosynthesis and catabolism in plants. The activation of JA biosynthesis has been well documented; however, how plants repress JA catabolism upon pathogen infection remains elusive. In this study, we identified and characterized Botrytis cinerea-induced F-box protein 1 (BFP1) in Arabidopsis. The expression of BFP1 was induced by B. cinerea in a JA signaling-dependent manner, and BFP1 protein was critical for plant defense against B. cinerea and plant response to JA. In addition, BFP1 overexpression increased plant defenses against broad-spectrum pathogens without fitness costs. Further experiments demonstrated that BFP1 interacts with and mediates the ubiquitination and degradation of jasmonic acid oxidases (JAOs, also known as jasmonate-induced oxygenases, JOXs), the enzymes that hydroxylate JA to 12OH-JA. Consistent with this, BFP1 affects the accumulation of JA and 12OH-JA during B. cinerea infection. Moreover, mutation of JAO2 complemented the phenotypes of the bfp1 mutant. Collectively, our results unveil a new mechanism used by plants to activate immune responses upon pathogen infection: suppressing JA catabolism.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Resistência à Doença , Proteínas de Arabidopsis/metabolismo , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Botrytis/fisiologia , Doenças das Plantas , Regulação da Expressão Gênica de Plantas , Ácido Salicílico/metabolismoRESUMO
Plasminogen (Plg) is a highly abundant protein found in the plasma component of blood and is necessary for the degradation of fibrin, collagen, and other structural components of tissues. This fibrinolytic system is utilized by several pathogenic species of bacteria to manipulate the host plasminogen system and facilitate invasion of tissues during infection by modifying the activation of this process through the binding of Plg at their surface. Bacteroides fragilis is the most commonly isolated Gram-negative obligate anaerobe from human clinical infections, such as intra-abdominal abscesses and anaerobic bacteraemia. The ability of B. fragilis to convert plasminogen (Plg) into plasmin has been associated with an outer membrane protein named Bfp60. In this study, we characterized the function of Bfp60 protein in B. fragilis 638R by constructing the bfp60 defective strain and comparing its with that of the wild type regarding binding to laminin-1 (LMN-1) and activation of Plg into plasmin. Although the results showed in this study indicate that Bfp60 surface protein of B. fragilis is important for the recognition of LMN-1 and Plg activation, a significant slow activation of Plg into plasmin was observed in the mutant strain. For that reason, the possibility of another unidentified mechanism activating Plg is also present in B. fragilis cannot be discarded. The results demonstrate that Bfp60 protein is responsible for the recognition of laminin and Plg-plasmin activation. Although the importance of this protein is still unclear in the pathogenicity of the species, it is accepted that since other pathogenic bacteria use this mechanism to disseminate through the extracellular matrix during the infection, it should also contribute to the virulence of B. fragilis.
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Adesinas Bacterianas/metabolismo , Aderência Bacteriana , Proteínas da Membrana Bacteriana Externa/metabolismo , Bacteroides fragilis/fisiologia , Interações Hospedeiro-Patógeno , Laminina/metabolismo , Plasminogênio/metabolismo , Adesinas Bacterianas/genética , Proteínas da Membrana Bacteriana Externa/genética , Bacteroides fragilis/genética , Fibrinolisina/metabolismo , Técnicas de Inativação de Genes , Humanos , Ligação ProteicaRESUMO
Tubulation is a common cellular process involving the formation of membrane tubes ranging from 50 nm to 1 µm in diameter. These tubes facilitate intercompartmental connections, material transport within cells and content exchange between cells. The high curvature of these tubes makes them specific targets for proteins that sense local geometry. In vitro, similar tubes have been created by pulling on the membranes of giant unilamellar vesicles. Optical tweezers and micromanipulation are typically used in these experiments, involving the manipulation of a GUV with a micropipette and a streptavidin-coated bead trapped in optical tweezers. The interaction forms streptavidin/biotin bonds, leading to tube formation. Here, we propose a cost-effective alternative using only micromanipulation techniques, replacing optical tweezers with a Biomembrane Force Probe (BFP). The BFP, employing a biotinylated erythrocyte as a nanospring, allows for the controlled measurement of forces ranging from 1 pN to 1 nN. The BFP has been widely used to study molecular interactions in cellular processes, extending beyond its original purpose. We outline the experimental setup, tube formation and characterization of tube dimensions and energetics, and discuss the advantages and limitations of this approach in studying membrane tubulation.
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Enteropathogenic Escherichia coli (EPEC) is an important cause of diarrhoeal disease in human infants. EPEC strains are defined by the presence of specific virulence factors including intimin (encoded by the eae gene) and bundle forming pili (Bfp). Bfp is encoded by the bfp operon and includes the bfpA gene for the major pilus subunit. By definition, Bfp are only present in typical EPEC (tEPEC), for which, humans are considered to be the only known natural host. This study detected tEPEC in faecal samples from a wild Australian fruit bat species, the grey-headed flying-fox (Pteropus poliocephalus). Whole genome sequencing of 61 E. coli isolates from flying-foxes revealed that 21.3 % (95%CI: 13 %-33 %) were tEPEC. Phylogenetic analyses showed flying-fox tEPEC shared evolutionary lineages with human EPEC, but were predominantly novel sequence types (9 of 13) and typically harboured novel bfpA variants (11 of 13). HEp-2 cell adhesion assays showed adherence to human-derived epithelial cells by all 13 flying-fox tEPEC, indicating that they all carried functional Bfp. Using an EPEC-specific duplex PCR, it was determined that tEPEC comprised 17.4 % (95%CI: 13 %-22 %) of 270 flying-fox E. coli isolates. Furthermore, a tEPEC-specific multiplex PCR detected the eae and bfpA virulence genes in 18.0 % (95%CI: 8.0 %-33.7 %) of 506 flying-fox faecal DNA samples, with occurrences ranging from 1.3 % to 87.0 % across five geographic areas sampled over a four-year period. The identification of six novel tEPEC sequence types and five novel bfpA variants suggests flying-foxes carry bat-specific tEPEC lineages. However, their close relationship with human EPEC and functional Bfp, indicates that flying-fox tEPEC have zoonotic potential and that dissemination of flying-fox tEPEC into urban environments may pose a public health risk. The consistent detection of tEPEC in flying-foxes over extensive geographical and temporal scales indicates that both wild grey-headed flying-foxes and humans should be regarded as natural tEPEC hosts.
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Quirópteros , Escherichia coli Enteropatogênica , Proteínas de Escherichia coli , Lactente , Animais , Humanos , Escherichia coli Enteropatogênica/genética , Adesinas Bacterianas/genética , Filogenia , Proteínas de Escherichia coli/genética , AustráliaRESUMO
Protein modification by glycosylphosphatidylinositol (GPI) takes place in the endoplasmic reticulum (ER). GPI-anchored proteins (GPI-APs) formed in the ER are transported to the cell surface through the Golgi apparatus. During transport, the GPI-anchor structure is processed. In most cells, an acyl chain modified to the inositol of GPI is removed by a GPI-inositol deacylase, PGAP1, in the ER. Inositol-deacylated GPI-APs become sensitive to bacterial phosphatidylinositol-specific phospholipase C (PI-PLC). We previously reported that GPI-APs are partially resistant to PI-PLC when PGAP1 activity is weakened by the deletion of selenoprotein T (SELT) or cleft lip and palate transmembrane protein 1 (CLPTM1). In this study, we found that the loss of TMEM41B, an ER-localized lipid scramblase, restored PI-PLC sensitivity of GPI-APs in SELT-knockout (KO) and CLPTM1-KO cells. In TMEM41B-KO cells, the transport of GPI-APs as well as transmembrane proteins from the ER to the Golgi was delayed. Furthermore, the turnover of PGAP1, which is mediated by ER-associated degradation, was slowed in TMEM41B-KO cells. Taken together, these findings indicate that inhibition of TMEM41B-dependent lipid scrambling promotes GPI-AP processing in the ER through PGAP1 stabilization and slowed protein trafficking.
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Fenda Labial , Fissura Palatina , Humanos , Glicosilfosfatidilinositóis/metabolismo , Proteínas Ligadas por GPI/genética , Inositol/metabolismoRESUMO
The purpose of the study was to evaluate the components of overweight, obesity, and body mass components among children aged 7 to 13 years against important sociodemographic factors. The analyses considered 315 school-age children from 7 to 13 years of age (164 boys and 151 girls). Each subject was assessed for body weight and height, body weight category, and main sociodemographic factors. Body mass components of body mass (body-fat percentage (BFP), muscle tissue, fat-free mass (FFM), and total body water (TBW) levels) were evaluated using the electrical bioimpedance method (BIA) and the TANITA 780 MC analyzer. A statistical analysis showed significant differences between the body composition of children living in cities in relation to children living in small towns and villages, and no significant differences were found between the results of children living in small towns and children living in villages. The presence of statistically significant differences between the values of the parameters of body composition of the studied children was demonstrated depending on the level of education of their fathers. The presence of statistically significant relationships between BMI of mothers and BFP of their children (p = 0.003), FFM (p = 0.003), muscle tissue (p = 0.001), and TBW (p = 0.001) has been demonstrated. The higher content of adipose tissue in children is strongly dependent on the higher BMI and body mass category of the mother, as well as the lower level of education of the father. The place of residence also significantly affects both the body fat content and the total body water content of body hydration. Living in the city is associated with better body composition.
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Composição Corporal , Adolescente , Criança , Feminino , Humanos , Masculino , Composição Corporal/fisiologia , Índice de Massa Corporal , Peso Corporal , Impedância Elétrica , Fatores SocioeconômicosRESUMO
Several cases of Guillain-Barré Syndrome (GBS) associated with COVID-19 vaccination have been reported, including the rare subtype known as Bilateral Facial Palsy with paresthesias (BFP). To date, it is not known whether a causal relationship may exist between the two. We report 9 cases of BFP in patients vaccinated against COVID-19 in the previous month. Nerve conduction studies revealed demyelinating polyneuropathy in 4 patients, and 5 presented bilateral, focal facial nerve involvement, exclusively. Ganglioside antibody panel was positive in 4 patients (anti-GM1=2, anti-GD1a=1 and anti-sulfatide=1). Seven patients received intravenous immunoglobulin treatment, one plasma exchange, and one patient died from sudden cardiac arrest following arrhythmia before treatment could be administered. Rates of BFP following COVID-19 vaccination, did not differ from those reported in previous series. Epidemiological studies are essential to determine whether a causal relationship may exist between this rare form of GBS and COVID-19 vaccination.
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Vacinas contra COVID-19 , Paralisia Facial , Síndrome de Guillain-Barré , Parestesia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Paralisia Facial/diagnóstico , Paralisia Facial/epidemiologia , Síndrome de Guillain-Barré/epidemiologia , Humanos , Parestesia/diagnóstico , Parestesia/epidemiologiaRESUMO
Heart failure (HF) is the end stage of various cardiovascular diseases, with high morbidity and mortality, and is associated with a poor prognosis. One of the primary causes of HF is aortic valve disease, manifested by progressive aortic valve stenosis (AVS), resulting in increased left ventricular load, ventricular hypertrophy, ultimately ventricular dysfunction, and HF. Early assessment of the degree of cardiomyopathy and timely intervention is expected to improve patients' cardiac function and delay or even avoid the occurrence of HF. The Wnt signaling pathway is mainly involved in regulating myocardial insufficiency after valve stenosis. Connexin 43 protein (Cx43) is an essential target of Wnt signaling pathway that forms gap junction (GJ) structures and is widely distributed in various organs and tissues, especially in the heart. The distribution and transformation of Cx43 among cardiac cells are crucial for the development of HF. To specifically label Cx43 in vivo, we established a new Cx43-BFP-GFP mouse model with two loxp sites on both sides of the tag BFP-polyA box, which can be removed by Cre recombination. This double-reporter line endowed us with a powerful genetic tool for determining the area, spatial distribution, and functional status of Cx43. It also indicated changes in electrical conduction between cells in a steady or diseased state.
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CRISPR/Cas9-mediated gene editing has been rapidly and widely applied in many organisms for delicate genetic manipulation, including human-induced pluripotent stem cells (iPSCs). Gene editing in human iPSCs is promising for genetics and biomedical research due to that gene-edited iPSC still possesses the potential to be differentiated into any cell lineages. In many cases, the generation of Cas9 expressing cell lines is a prerequisite toward performing successful editing of multiplex genes of interest. Here, we describe a simple, effective method to generate stable Cas9 expressing human iPSCs with high Cas9 activity. In this method, stable Cas9 expressing monoclonal human iPSC lines were generated through lentiviral transduction of Cas9 cassette, followed by blasticidin selection and subcloning with low seeding density. After colonies isolation and expansion, a BFP-GFP reporter assay was applied to validate the Cas9 activities of multiple monoclonal lines by flow cytometry (FACS). These Cas9 expressing human iPSCs generated by our method are single cell-derived monoclonal lines with homogenous population and Cas9 activity of up to 99%.
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Células-Tronco Pluripotentes Induzidas , Sistemas CRISPR-Cas , Diferenciação Celular/genética , Linhagem Celular , Edição de Genes/métodos , HumanosRESUMO
Guillain-Barré syndrome (GBS) is an immune-mediated demyelinating disorder which attacks the peripheral nervous system. Antecedent infection or vaccine administration are known to precipitate the onset of this disorder. Its typical presentation leads to a symmetric, rapidly progressive, ascending paresis with associated sensory deficits and impaired reflexes. We present a rare case of a bi-facial diplegia variant of GBS, within four weeks of the COVID-19 vaccination. Due to its chronology, clinical manifestations, and cerebrospinal fluid (CSF) findings, we propose this case to be a rare complication of the COVID-19 vaccination.
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BACKGROUND: Exercise is generally recognized as beneficial to prevent obesity; however, it is not clear which indicator can better reflect the benefits, especially in adolescents. The aim of this study was to describe the effects of exercise on body mass and fat indexes and to clarify the significance of different indexes in clinical use. METHODS: We conducted a prospective cohort study involving 1,941 freshmen from 2014, followed-up biennially until 2018. Various body mass and fat indexes, including weight, height, waist and hip circumference and body fat percentage (BFP), were measured. Physical activity and other variables were collected by questionnaire. All study participants were divided into two groups according to the frequency and intensity of exercise. RESULTS: Compared with the low frequency and intensity exercise group, the high frequency and intensity exercise group had a lower increase in BFP during the 4-year follow-up, and no significant differences were observed in the changes of other indexes between the groups. Even after adjusting, the high frequency and intensity exercise group still exhibited a higher likelihood of reducing BFP. CONCLUSIONS: High frequency and intensity exercise provides benefits for reducing BFP. No other body mass or fat indexes showed any association. BFP could be a much more sensitive indicator to detect and control obesity in adolescents.
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Adiposidade , Exercício Físico , Tecido Adiposo , Adolescente , Índice de Massa Corporal , Seguimentos , Humanos , Obesidade , Estudos ProspectivosRESUMO
BACKGROUND: Worldwide around 2 million deaths occur every year due to diarrhoeal illnesses among children less than 5 years of age. Among diarrhoeagenic Escherichia coli, Enteropathogenic E. coli (EPEC) is highly prevalent in both community and hospital settings and is one of the main causes of persistent diarrhea in children in developing countries. EPEC remains underdiagnosed in India due to lack of conventional tools for identification. METHODS: We in this study investigated the prevalence and regional variation of EPEC in paediatric population suffering from diarrhoea in East Delhi, India. Two hundred stool samples were collected from children, aged between 0.5 and 5 years, with acute diarrhoea. E. coli were identified by conventional tests and PCR. RESULTS: We observed 7% atypical EPEC (aEPEC) and 2.5% typical EPEC (tEPEC), with an overall 9.5% EPEC prevalence amongst total samples. E. coli phylogenetic group A was the predominant. The most common age group affected was 6-23 months with common symptoms being vomiting, watery diarrhoea and severe dehydration. High drug resistance pattern was observed in EPEC isolates. CONCLUSION: The study depicts a changing trend of aEPEC over tEPEC in children less than 5 years with diarrhoea, an emerging drug resistant enteropathogen and a public health concern demanding monitoring and surveillance.
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Escherichia coli Enteropatogênica , Infecções por Escherichia coli , Proteínas de Escherichia coli , Criança , Pré-Escolar , Diarreia/epidemiologia , Infecções por Escherichia coli/epidemiologia , Proteínas de Escherichia coli/genética , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , FilogeniaRESUMO
BACKGROUND: The rising prevalence of obesity in military personnel has raised great concerns. Previous studies suggest that body mass index (BMI)- and waist-to-hip ratio (WHR)-based obesity classifications in US military personnel and firefighters have high false negative and subsequently cause obesity misclassification. OBJECTIVE: To determine whether BMI and WHR could reflect the fat mass of Chinese military personnel. METHODS: Three hundred fifty-three male Chinese military personnel and 380 age-matched male adults were recruited. Obesity classification was defined by BMI, WHR, and body fat percentage (BFP). RESULTS: Chinese military personnel had extremely low obesity rate determined by either BFP (0.3%) or BMI (0.6%). By combining overweight and obese individuals, BMI- and WHR-determined prevalence of overweight/obesity was 22.4% and 17.0% compared to BFP-based standard (4.0%) (P < 0.05). In reference to BFP, BMI and WHR have high false-positive rate compared to the control group. Further analysis showed that Chinese military personnel consisted of high percentage of BFPlowBMIhigh and/or BFPlowWHRhigh subpopulations. Eighty-one percent of BMIhigh and 78.3% of WHRhigh of them were BFP low. CONCLUSIONS: Chinese military personnel has extremely low obesity rate. BMI and WHR have high false-positive rates in reference to BFP, which cannot accurately reflect the mass of adipose tissue and leads to obesity misclassification.