RESUMEN
Tuft cells are a group of rare epithelial cells that can detect pathogenic microbes and parasites. Many of these cells express signaling proteins initially found in taste buds. It is, however, not well understood how these taste signaling proteins contribute to the response to the invading pathogens or to the recovery of injured tissues. In this study, we conditionally nullified the signaling G protein subunit Gγ13 and found that the number of ectopic tuft cells in the injured lung was reduced following the infection of the influenza virus H1N1. Furthermore, the infected mutant mice exhibited significantly larger areas of lung injury, increased macrophage infiltration, severer pulmonary epithelial leakage, augmented pyroptosis and cell death, greater bodyweight loss, slower recovery, worsened fibrosis and increased fatality. Our data demonstrate that the Gγ13-mediated signal transduction pathway is critical to tuft cells-mediated inflammation resolution and functional repair of the damaged lungs.To our best knowledge, it is the first report indicating subtype-specific contributions of tuft cells to the resolution and recovery.
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Subtipo H1N1 del Virus de la Influenza A , Transducción de Señal , Animales , Ratones , Subtipo H1N1 del Virus de la Influenza A/fisiología , Infecciones por Orthomyxoviridae , Lesión Pulmonar/metabolismo , Pulmón/patología , Inflamación , Células Epiteliales/metabolismo , Ratones Noqueados , Modelos Animales de EnfermedadRESUMEN
BACKGROUND AND AIMS: The association of cardiometabolic disease (CMD) with body muscle and fat mass remains unclear. Mid-arm muscle circumference (MAMC) and triceps skinfold (TSF) thickness are easily obtained measuring methods for these two body compositions. This study aimed to investigate the association of CMD with MAMC and TSF thickness among Chinese residents. METHODS: A total of 9440 eligible participants from the China Health and Nutrition Survey were included in the analysis. Associations of CMD prevalence with MAMC and TSF thickness were estimated using logistic regression models. Multivariable COX proportional-hazards regression models were used to estimate the effect of baseline MAMC and TSF thickness on subsequent CMD. RESULTS: Positive associations of CMD prevalence with MAMC (odds ratio [OR] = 1.169, 95% confidence interval [CI] 1.110-1.232, P < 0.001) and TSF thickness (OR = 1.313, 95%CI 1.240-1.390, P < 0.001) were observed in the cross-sectional analysis. In the longitudinal study, a 1-SD increase in MAMC was associated with a 13.6% increased risk of CMD incidence (hazard ratio [HR] = 1.136, 95%CI 1.073-1.204, P < 0.001), and a 1-SD increase in TSF thickness had a 17.6% increased risk of CMD incidence (HR = 1.176, 95%CI 1.084-1.276, P < 0.001). For the CMD components, both MAMC and TSF thickness contributed to increased incidences of hypertension (HR = 1.163, 95%CI 1.097-1.233, P < 0.001 in MAMC; HR = 1.218, 95%CI 1.110-1.336, P < 0.001 in TSF thickness) and diabetes mellitus (HR = 1.166, 95%CI 1.028-1.323, P = 0.017 in MAMC; HR = 1.352, 95%CI 1.098-1.664, P = 0.004 in TSF thickness). CONCLUSIONS: Individuals with higher MAMC and TSF thickness had an increased incidence of CMD, mainly hypertension and diabetes mellitus. This study revealed a seemingly counterintuitive association between body muscle mass and metabolic homeostasis. Although the potential mechanisms require further exploration, the impact of body muscle mass on metabolic health cannot be ignored.
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Enfermedades Cardiovasculares , Diabetes Mellitus , Hipertensión , Humanos , Estado Nutricional , Índice de Masa Corporal , Grosor de los Pliegues Cutáneos , Estudios Longitudinales , Estudios Transversales , Estudios Prospectivos , Músculos , Hipertensión/diagnóstico , Hipertensión/epidemiología , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiologíaRESUMEN
Tuft cells are a type of rare epithelial cells that have been recently found to utilize taste signal transduction pathways to detect and respond to various noxious stimuli and pathogens, including allergens, bacteria, protists and parasitic helminths. It is, however, not fully understood how many different types of pathogens they can sense or what exact molecular mechanisms they employ to initiate targeted responses. In this study, we found that an anaerobic pathobiont microbe, Ruminococcus gnavus (R. gnavus), can induce tuft cell proliferation in the proximal colon whereas the microbe's lysate can stimulate these proximal colonic tuft cells to release interleukin-25 (IL-25). Nullification of the Gng13 and Trpm5 genes that encode the G protein subunit Gγ13 and transient receptor potential ion channel Trpm5, respectively, or application of the Tas2r inhibitor allyl isothiocyanate (AITC), G protein Gßγ subunit inhibitor Gallein or the phospholipase Cß2 (PLCß2) inhibitor U73122 reduces R. gnavus-elicited tuft cell proliferation or IL-25 release or both. Furthermore, Gng13 conditional knockout or Trpm5 knockout diminishes the expression of gasdermins C2, C3 and C4, and concomitantly increases the activated forms of caspases 3, 8 and 9 as well as the number of TUNEL-positive apoptotic cells in the proximal colon. Together, our data suggest that taste signal transduction pathways are not only involved in the detection of R. gnavus infection, but also contribute to helping maintain gasdermin expression and prevent apoptotic cell death in the proximal colon, and these findings provide another strategy to combat R. gnavus infection and sheds light on new roles of taste signaling proteins along with gasdermins in protecting the integrity of the proximal colonic epithelium.
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Gusto , Canales de Potencial de Receptor Transitorio , Ruminococcus , Transducción de Señal , ColonRESUMEN
Pathological angiogenesis plays a major role in many disease processes, including cancer and diabetic retinopathy. Antiangiogenic therapy is a potential management for pathologic angiogenesis. The novel synthetic compound 221S-1a, derived from captopril, tanshinol and borneol, may have antiangiogenic properties. On the basis of MS, NMR and HPLC analysis, the structure of 221S-1a was identified. The cellular uptake and metabolism of this compound was also observed. Next, the antiangiogenic properties of 221S-1a were evaluated in tumor-xenograft and OIR models in vivo. The inhibitory properties of 221S-1a on endothelial cell proliferation, migration, tube formation and sprouting were detected in vitro. Furthermore, 221S-1a induced G1/S phase arrest was detected by PI staining flow cytometry analysis and Cyclin D, Cyclin E expression. 221S-1a inhibited ERK1/2 activation and nuclear translocation, in addition to downregulation of c-Myc, a transcription factor that regulates cell cycle progression. Molecular docking indicated the interaction of 221S-1a with the ATP-binding site of ERK2, leading to the inhibition of ERK2 phosphorylation and a concomitant inhibition of ERK1 phosphorylation. In conclusion, 221S-1a inhibited the G1/S phase transition by blocking the ERK1/2/c-Myc pathway to reduce tumor and OIR retinal angiogenesis. These novel findings suggest that 221S-1a is a potential pharmacologic candidate for treating pathological angiogenesis.
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Proteínas Proto-Oncogénicas c-myc , Transducción de Señal , Humanos , Simulación del Acoplamiento Molecular , Neovascularización Patológica/tratamiento farmacológico , Proliferación CelularRESUMEN
Sympathetic stress is prevalent in cardiovascular diseases. Sympathetic overactivation under strong acute stresses triggers acute cardiovascular events including myocardial infarction (MI), sudden cardiac death, and stress cardiomyopathy. α1-ARs and ß-ARs, two dominant subtypes of adrenergic receptors in the heart, play a significant role in the physiological and pathologic regulation of these processes. However, little is known about the functional similarities and differences between α1- and ß-ARs activated temporal responses in stress-induced cardiac pathology. In this work, we systematically compared the cardiac temporal genome-wide profiles of acute α1-AR and ß-AR activation in the mice model by integrating transcriptome and proteome. We found that α1- and ß-AR activations induced sustained and transient inflammatory gene expression, respectively. Particularly, the overactivation of α1-AR but not ß-AR led to neutrophil infiltration at one day, which was closely associated with the up-regulation of chemokines, activation of NF-κB pathway, and sustained inflammatory response. Furthermore, there are more metabolic disorders under α1-AR overactivation compared with ß-AR overactivation. These findings provide a new therapeutic strategy that, besides using ß-blocker as soon as possible, blocking α1-AR within one day should also be considered in the treatment of acute stress-associated cardiovascular diseases.
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Enfermedades Cardiovasculares , Receptores Adrenérgicos beta , Animales , Ratones , Receptores Adrenérgicos beta/genética , Receptores Adrenérgicos beta/metabolismo , Corazón , Arritmias Cardíacas , Inflamación/metabolismo , Receptores Adrenérgicos alfa 1/genética , Receptores Adrenérgicos alfa 1/metabolismoRESUMEN
Our initial studies detected elevated levels of 3,4-dihydroxyphenyllactic acid (DHPLA) in urine samples of patients with severe heart disease when compared with healthy subjects. Given the reported anti-inflammatory properties of DHPLA and related dihydroxylated phenolic acids (DPAs), we embarked on an exploratory multi-centre investigation in patients with no urinary tract infections to establish the possible pathophysiological significance and therapeutic implications of these findings. Chinese and Caucasian patients being treated for severe heart disease or those conditions associated with inflammation (WBC ≥ 10 ×109/L or hsCRP ≥ 3.0 mg/L) and/or hypoxia (PaO2 ≤ 75 mmHg) were enrolled; their urine samples were analyzed by HPLC, HPLC-MS, GC-MS and biotransformation assays. DHPLA was detected in urine samples of patients, but undetectable in healthy volunteers. Dynamic monitoring of inpatients undergoing treatment showed their DHPLA levels declined in proportion to their clinical improvement. In DHPLA-positive patients' fecal samples, Proteus vulgaris and P. mirabilis were more abundant than healthy volunteers. In culture, these gut bacteria were capable of reversible interconversion between DOPA and DHPLA. Furthermore, porcine and rodent organs were able to metabolize DOPA to DHPLA and related phenolic acids. The elevated levels of DHPLA in these patients suggest bioactive DPAs are generated de novo as part of a human's defense mechanism against disease. Because DHPLA isolated from Radix Salvia miltiorrhizae has a multitude of pharmacological activities, these data underpin the scientific basis of this medicinal plant's ethnopharmacological applications as well as highlighting the therapeutic potential of endogenous, natural or synthetic DPAs and their derivatives in humans.
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Cardiopatías , Inflamación , Humanos , Porcinos , Animales , Hipoxia , DihidroxifenilalaninaRESUMEN
Clinical indicators do not adequately predict the long-term prognosis of patients with ST-segment elevation myocardial infarction (STEMI) following percutaneous coronary intervention (PCI). The low-density lipoprotein (LDL)/high-density lipoprotein (HDL) ratio is expected to be a reliable predictor of the long-term prognosis of these patients. This study aimed to explore the correlation between the LDL/HDL ratio and long-term prognosis in STEMI patients undergoing PCI. Patients with confirmed STEMI who underwent PCI in 7 hospitals in China from January 2009 to December 2011 were enrolled. Information about clinical endpoints, including all-cause death and major adverse cardiovascular events, was collected. Overall, 915 patients were included for analysis, the average follow-up time was 112.2 months. According to the LDL/HDL ratio, the patients were divided into 3 groups using the three-quantile method: low (LDL/HDL≤1.963), medium (1.963Asunto(s)
Intervención Coronaria Percutánea
, Infarto del Miocardio con Elevación del ST
, HDL-Colesterol
, Estudios de Cohortes
, Humanos
, Lipoproteínas HDL
, Infarto del Miocardio con Elevación del ST/cirugía
, Resultado del Tratamiento
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BACKGROUND: Chronological age (CA) is not a perfect proxy for the true biological aging status of the body. A new biological aging measure, phenotypic age (PhenoAge), has been shown to capture morbidity and mortality risk in the general US population and diverse subpopulations. This study was aimed at evaluating the association between PhenoAge and long-term outcome of patients with multivessel coronary artery disease (CAD). METHODS: A total of 609 multivessel CAD patients who received PCI attempt and with follow-up were enrolled. The clinical outcome was all-cause mortality on follow-up. PhenoAge was calculated using an equation constructed from CA and 9 clinical biomarkers. Cox proportional hazards regression models and receiver operating characteristic (ROC) curves were performed to evaluate the association between PhenoAge and mortality. RESULTS: Overall, patients with more diseases had older PhenoAge and phenotypic age acceleration (PhenoAgeAccel). After a median follow-up of 33.5 months, those with positive PhenoAgeAccel had a significantly higher incidence of all-cause mortality (P = 0.001). After adjusting for CA, Cox proportional hazards models showed that both PhenoAge and PhenoAgeAccel were significantly associated with all-cause mortality. Even after further adjusting for confounding factors, each 10-year increase in PhenoAge was also associated with a 51% increased mortality risk. ROC curves revealed that PhenoAge, with an area under the curve of 0.705, significantly outperformed CA, the individual clinical chemistry measure, and other risk factors. When reexamining the ROC curves using various combinations of variables, we found that PhenoAge provides additional predictive power to all models. CONCLUSIONS: In conclusion, PhenoAge was strongly associated with all-cause mortality even after adjusting for CA. Our findings suggest that PhenoAge measure may be complementary in predicting mortality risk for patients with multivessel CAD.
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Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Envejecimiento , Enfermedad de la Arteria Coronaria/etiología , Humanos , Intervención Coronaria Percutánea/efectos adversos , Modelos de Riesgos Proporcionales , Factores de Riesgo , Resultado del TratamientoRESUMEN
Clinical indicators do not adequately predict the long-term prognosis of patients with ST-segment elevation myocardial infarction (STEMI) following percutaneous coronary intervention (PCI). The low-density lipoprotein (LDL)/high-density lipoprotein (HDL) ratio is expected to be a reliable predictor of the long-term prognosis of these patients. This study aimed to explore the correlation between the LDL/HDL ratio and long-term prognosis in STEMI patients undergoing PCI. Patients with confirmed STEMI who underwent PCI in 7 hospitals in China from January 2009 to December 2011 were enrolled. Information about clinical endpoints, including all-cause death and major adverse cardiovascular events, was collected. Overall, 915 patients were included for analysis, the average follow-up time was 112.2 months. According to the LDL/HDL ratio, the patients were divided into 3 groups using the three-quantile method: low (LDL/HDL≤1.963), medium (1.963<LDL/HDL<2.595), and high (LDL/HDL≥2.595) LDL/HDL groups. The rate of coronary revascularization was higher in the high LDL/HDL group (28.52%) than in the low (17.38%, P=0.001) and medium (19.34%, P=0.010) LDL/HDL groups. The hazard ratio of coronary revascularization was significantly higher in the high LDL/HDL group than in the low (P=0.007) and medium (P=0.004) LDL/HDL groups. Increased LDL/HDL ratio was an independent risk factor for long-term coronary revascularization in STEMI patients undergoing PCI (HR=1.231, 95%CI: 1.023-1.482, P=0.028). These findings suggest that an increased LDL/HDL ratio was an independent risk factor for long-term coronary revascularization in STEMI patients undergoing PCI. The risk of coronary revascularization was significantly increased in patients with LDL/HDL≥2.595.
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Assessing congestion is challenging but important to patients with chronic heart failure (CHF). However, there are limited data regarding the association between estimated plasma volume status (ePVS) determined using hemoglobin/hematocrit data and outcomes in patients with stable CHF. We prospectively analyzed 231 patients; the median follow-up period was 35.6 months. We calculated ePVS at admission using the Duarte and Strauss formula, derived from hemoglobin and hematocrit ratios and divided patients into three groups. The primary outcome was a composite of all-cause mortality or heart failure rehospitalization. Among 274 patients (61.98 years of age, 2.3% male), the mean ePVS was 3.98±0.90 dL/g. The third ePVS tertile had a higher proportion of primary outcome (71.4%) than the first or second tertile (48.1% and 59.7%, respectively; p=0.013). On multivariable Cox analysis, after adjusting for potential confounders, higher ePVS remained significantly associated with increased rate of primary outcome (adjusted HR 1.567, 95% CI 1.267 to 1.936; p<0.001). Kaplan-Meier survival analyses showed that the occurrence of primary outcome, all-cause mortality and rehospitalization increased progressively from first to third tertiles (p=0.006, 0.014 and 0.001; respectively). In receiver operating characteristic analysis, the area under the curve of ePVS for primary outcome was 0.645. ePVS determined using hemoglobin and hematocrit was independently associated with clinical outcomes for patients with stable CHF. Our study thus further strengthens the evidence that ePVS has important prognostic value in patients with stable CHF. Trial registration number ChiCTR-ONC-14004463.
Asunto(s)
Insuficiencia Cardíaca Sistólica , Volumen Plasmático , Enfermedad Crónica , Femenino , Insuficiencia Cardíaca Sistólica/diagnóstico , Hematócrito , Hemoglobinas , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , PronósticoRESUMEN
Aim: The aim of present study is to evaluate the diagnostic and prognostic value of plasma galectin 3 (Gal-3) for HF originating from different causes. Methods: We investigated the plasma levels and expression of Gal-3 in cardiac tissues in two transgenic (TG) strains of mice with cardiomyocyte-restricted overexpression of either ß2- adrenergic receptor (ß2- AR TG) or Mammalian sterile 20-like kinase 1 (Mst1-TG) in the present study. Additionally, 166 patients suffering from heart failure with reduced ejection fraction (HFrEF) in two hospitals within the Shaanxi province were examined in this study. All these patients were treated according to the Chinese HF guidelines of 2014; subsequently, they were followed up for 50 months, and we analyzed the prediction value of baseline Gal-3 to endpoints in these patients. Results: Gal-3 was localized in the cytoplasm and nucleus of cardiomyocytes, often formed aggregates in Mst1-TG mice. Extracellular Gal-3 staining was uncommon in Mst1-TG hearts. However, in ß2-AR TG mice, although Gal-3 was also expressed in myocardial cells, it was more highly expressed in interstitial cells (e.g., fibroblasts and macrophages). Plasma Gal-3 was comparable between nTG and Mst1-TG mice. However, plasma Gal-3 was higher in ß2-AR TG mice than in nTG mice. In the cohort of HFrEF patients, the median plasma Gal-3 concentration was 158.42 pg/mL. All participants were divided into two groups according to Gal-3 levels. Patients with Gal-3 concentrations above the median were older, and had lower plasma hemoglobin, but higher plasma creatinine, tissue inhibitor of metalloproteinases 1 (TIMP-1), left ventricular end systolic diameter (LVESD), left ventricular end-systolic volumes (LVESV) and end-diastolic, as well as left ventricular end-diastolic volumes (LVEDV). Spearman correlation analysis revealed that Gal-3 was positively correlated with TIMP-1 (r = 0.396, P < 0.001), LVESV (r = 0.181, P = 0.020) and LVEDV (r = 0.190, P = 0.015). The 50-month clinical follow-up revealed 43 deaths, 97 unplanned re-hospitalizations, and 111 composite endpoint events. Cox analysis demonstrated that although Gal-3 did not provide any prognostic value in either total-HF subjects or coronary-heart-disease (CHD) patients, it did provide prognostic value in non-CHD patients. Conclusion: Although plasma Gal-3 is associated with TIMP-1 and echocardiographic parameters, the diagnostic and prognostic value of Gal-3 in HFrEF is determined by the etiology of HF.
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BACKGROUND: The endogenous lipid molecule sphingosine-1-phosphate (S1P) has received attention in the cardiovascular field due to its significant cardioprotective effects, as revealed in animal studies. The purpose of our study was to identify the distribution characteristics of S1P in systolic heart failure patients and the prognostic value of S1P for long-term prognosis. METHODS: We recruited 210 chronic systolic heart failure patients from June 2014 to December 2015. Meanwhile 54 healthy people in the same area were selected as controls. Plasma S1P was measured by liquid chromatography-tandem mass spectrometry. Patients were grouped according to the baseline S1P level quartiles, and restricted cubic spline plots described the association between S1P and all-cause death. Cox proportional hazard analysis was used to determine the relationship between category of S1P and all-cause death. RESULTS: Compared with the control group, the plasma S1P in chronic heart failure patients demonstrated a higher mean level (1.269 µmol/L vs 1.122 µmol/L, P = 0.006) and a larger standard deviation (0.441 vs 0.316, P = 0.022). Based on multivariable Cox regression with restricted cubic spline analysis, a non-linear and U-shaped association between S1P levels and the risk of all-cause death was observed. After a follow-up period of 31.7 ± 10.3 months, the second quartile (0.967-1.192 µml/L) with largely normal S1P levels had the lowest all-cause mortality and either an increase (adjusted HR = 2.368, 95%CI 1.006-5.572, P = 0.048) or a decrease (adjusted HR = 0.041, 95%CI 0.002-0.808, P = 0.036) predicted a worse prognosis. The survival curves showed that patients in the lowest quartile and highest quartile were at a higher risk of death. CONCLUSIONS: Plasma S1P levels in systolic heart failure patients are related to the long-term all-cause mortality with a U-shaped correlation. TRIAL REGISTRATION: CHiCTR, ChiCTR-ONC-14004463. Registered 20 March 2014.
Asunto(s)
Insuficiencia Cardíaca Sistólica/sangre , Insuficiencia Cardíaca Sistólica/mortalidad , Lisofosfolípidos/sangre , Esfingosina/análogos & derivados , Adulto , Anciano , Causas de Muerte , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Esfingosina/sangreRESUMEN
Commercial interests in indoor localization have been increasing in the past decade. The success of many applications relies at least partially on indoor localization that is expected to provide reliable indoor position information. Wi-Fi received signal strength (RSS)-based indoor localization techniques have attracted extensive attentions because Wi-Fi access points (APs) are widely deployed and we can obtain the Wi-Fi RSS measurements without extra hardware cost. In this paper, we propose a hierarchical classification-based method as a new solution to the indoor localization problem. Within the developed approach, we first adopt an improved K-Means clustering algorithm to divide the area of interest into several zones and they are allowed to overlap with one another to improve the generalization capability of the following indoor positioning process. To find the localization result, the K-Nearest Neighbor (KNN) algorithm and support vector machine (SVM) with the one-versus-one strategy are employed. The proposed method is implemented on a tablet, and its performance is evaluated in real-world environments. Experiment results reveal that the proposed method offers an improvement of 1.4% to 3.2% in terms of position classification accuracy and a reduction of 10% to 22% in terms of average positioning error compared with several benchmark methods.
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Aim: Heart failure (HF) is the end stage of various cardiovascular diseases. However, the precise regulation of gene expression profiles and functional mechanisms of long non-coding RNAs (lncRNAs) in HF remain to be elucidated. The present study aimed to identify the differentially expressed profiles and interaction of messenger RNAs (mRNAs) and lncRNAs in pressure overload-induced HF. Methods: Male Sprague-Dawley rats were randomly divided into the HF group and the sham-operated group. HF was induced by the transverse aortic constriction (TAC) surgery. The cardiac expression profiles of mRNAs and lncRNAs in HF were investigated using the microarray. Bioinformatics analyses and co-expression network construction were performed from the RNA sequencing data. Results: The expression profiles of mRNAs and lncRNAs showed significant differences between HF and controls. A total of 147 mRNAs and 162 lncRNAs were identified to be differentially expressed with a fold change of >2 in HF. The relative expression levels of several selected mRNAs and lncRNAs were validated by quantitative PCR. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses indicated that diverse pathways were involved in the molecular mechanisms of cardiac hypertrophy and HF including immune response, smooth muscle contraction, ion transmembrane transport. The mRNA-lncRNA and transcription factors (TFs)-lncRNA co-expression networks were constructed and several genes and TFs were identified as key regulators in the pathogenesis of HF. Further functional prediction showed that the lncRNA NONRATT013999 was predicted to cis-regulate mRNA CDH11, and NONRATT027756 was predicted to trans-regulate HCN4. Conclusion: This study revealed specific expression regulation and potential functions of mRNAs and lncRNAs in pressure overload-induced HF. These results will provide new insights into the underlying mechanisms and potential therapeutic targets for HF.
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In this study, a newly strain named Clostridium butyricum YJH-09 were isolated from the sample of pond soil and identified through physiological, biochemical and 16S rDNA analysis. Then, the dhaT gene encoding a novel 1,3-propanediol dehydrogenase (PDOR) was cloned from this strain and expressed in Escherichia coli BL21(DE3). Subsequently, the recombinant PDOR was purified and the optimal pH and temperature, specific activities and kinetic parameter were investigated. Furthermore, the whole cells of Clostridium butyricum YJH-09 mixed with BL21-dhaT were used to produce 1,3-PD through co-biotransformation. As results, 25.88g/L of 1,3-PD was generated with 0.54g/g yield from 50g/L glycerol in 30h, and the 1,3-PD production was increased more than 2-fold compared with wild type strain alone. This research would offer useful information for further development of the biosynthesis of 1,3-PD.
Asunto(s)
Alcohol Deshidrogenasa , Clostridium butyricum/metabolismo , Glicoles de Propileno , Biotransformación , ADN Bacteriano , Fermentación , GlicerolRESUMEN
In the present study, a new strain of Lactobacillus brevis producing d-tagatose was isolated and identified. Then, the l-arabinose isomerase (L-AI) of this strain was displayed on the spore surface of Bacillus subtilis DB403 by using an anchoring protein CotG and a peptide linker (Gly-Gly-Gly-Gly-Ser). This displayed L-AI with high specific activity and stability was used as a novel immobilized biocatalyst for producing d-tagatose through batch and semi-continuous biotransformation. The conversion rate of d-tagatose from 125â¯g/L d-galactose was achieved 79.7% at 28â¯h, and the volumetric productivity reached 4.3â¯g/L/h at 20â¯h. Furthermore, the displayed L-AI showed a good performance on the reusability and remained 87% of the specific activity and 40.7% of the conversion rate after five recycles. A high efficient immobilized method for producing food-grade d-tagatose was established using spore surface-displayed L-AI.
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Isomerasas Aldosa-Cetosa/metabolismo , Hexosas/metabolismo , Levilactobacillus brevis/enzimología , 4-Cloro-7-nitrobenzofurazano/análogos & derivados , Biotransformación , Galactosa , Lisina/análogos & derivados , Esporas BacterianasRESUMEN
In this study, we applied different sizes of gold nanoparticles (Au-NPs) to isoproterenol (ISO)-induced hyperthyroid heart disease rats (HHD rats). Single dose of 5, 40, 100 nm Au-NPs were injected intravenously. Cardiac safety tests were evaluated by cardiac marker enzymes in serum and cardiac accumulation of Au-NPs were measured by ICP-MS. Our results showed that size-dependent cardiac effects of Au-NPs in ISO-induced hyperthyroid rats. 5 nm Au-NPs had some cardiac protective effect but little accumulation in heart, probably due to smaller size Au-NPs can adapt to whole body easily in vivo. Histological analysis and TUNEL staining showed that Au-NPs can induce pathological alterations including cardiac fibrosis, apoptosis in control groups, however they can protect HHD groups from these harmful effects. Furthermore, transmission electron microscopy and western blotting employed on H9C2 cells showed that autophagy presented in Au-NPs treated cells and that Au-NPs can decrease LC3 II turning to LC3 I and decrease APG7 and caspase 12 in the process in HHD groups, while opposite effects on control groups were presented, which could be an adaptive inflammation reacts. As there are few animal studies about using nanoparticles in the treatment of heart disease, our in vivo and in vitro studies would provide valuable information before they can be considered for clinical use in general.
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Oro/administración & dosificación , Cardiopatías/prevención & control , Hipertiroidismo/complicaciones , Isoproterenol/efectos adversos , Administración Intravenosa , Animales , Proteína 7 Relacionada con la Autofagia/metabolismo , Caspasa 12/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Oro/farmacocinética , Hipertiroidismo/inducido químicamente , Nanopartículas del Metal , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , RatasRESUMEN
1,3-Propanediol (1,3-PD) is one of the most important chemicals widely used as monomers for synthesis of some commercially valuable products, including cosmetics, foods, lubricants and medicines. Although 1,3-PD can be synthesized both chemically and biosynthetically, the latter offers more merits over chemical approach as it is economically viable, environmentally friendly and easy to carry out. The biosynthesis of 1,3-PD can be done by transforming glycerol or other similar substrates using some bacteria, such as Clostridium butyricum and Klebsiella pneumoniae. However, these natural microorganisms pose some bottlenecks like low productivity and metabolite inhibition. To overcome these problems, recent research efforts have been focused more on the development of new strains by modifying the genome through different techniques, such as mutagenesis and genetic engineering. Genetically engineered strains obtained by various strategies cannot only gain higher yield than wild types, but also overcome some of the barriers in production by the latter. This review paper presents an overview on the recent advances in the technological approaches to develop genetically engineered microorganisms for efficient biosynthesis of 1,3-PD.
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In the present study, a novel ardh gene encoding d-arabitol dehydrogenase (ArDH) was cloned and expressed in Escherichia coli from a new isolated strain of Gluconobacter sp. JX-05. Sequence analysis revealed that ArDH containing a NAD(P)-binding motif and a classical active site motif belongs to the short-chain dehydrogenase family. Subsequently, the optimal pH and temperature, specific activities and kinetic parameter of ArDH were determined. In the co-biotransformation by the whole cells of BL21-ardh and BL21-xdh, 26.1g/L xylitol was produced from 30g/L d-arabitol in 22h with a yield of 0.87g/g. The xylitol production was increased by more than two times as compared with that of Gluconobacter sp. alone, and was improved 10.1% than that of Gluconobacter sp. mixed with BL21-xdh.
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Gluconobacter/metabolismo , Xilitol/biosíntesis , Biotransformación , D-Xilulosa Reductasa/genética , OxidorreductasasRESUMEN
OBJECTIVE: Changing the current situation that doctors carry large amounts of paper medical records doctor's advice during clinical examination to improve the efficiency of examination. METHOD: Analysis of current business demand in doctor's clinical work, followed with a comprehensive improvement program. RESULT: Design a Tablet PC system comply with doctor's clinical demand in both software and hardware. CONCLUSION: By using the Tablet PC physicians improve the efficiency of work, realize the reengineering and optimization of traditional health services and management process.