ABSTRACT
BACKGROUND: NOTCH1 pathogenic variants are implicated in multiple types of congenital heart defects including hypoplastic left heart syndrome, where the left ventricle is underdeveloped. It is unknown how NOTCH1 regulates human cardiac cell lineage determination and cardiomyocyte proliferation. In addition, mechanisms by which NOTCH1 pathogenic variants lead to ventricular hypoplasia in hypoplastic left heart syndrome remain elusive. METHODS: CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9 genome editing was utilized to delete NOTCH1 in human induced pluripotent stem cells. Cardiac differentiation was carried out by sequential modulation of WNT signaling, and NOTCH1 knockout and wild-type differentiating cells were collected at day 0, 2, 5, 10, 14, and 30 for single-cell RNA-seq. RESULTS: Human NOTCH1 knockout induced pluripotent stem cells are able to generate functional cardiomyocytes and endothelial cells, suggesting that NOTCH1 is not required for mesoderm differentiation and cardiovascular development in vitro. However, disruption of NOTCH1 blocks human ventricular-like cardiomyocyte differentiation but promotes atrial-like cardiomyocyte generation through shortening the action potential duration. NOTCH1 deficiency leads to defective proliferation of early human cardiomyocytes, and transcriptomic analysis indicates that pathways involved in cell cycle progression and mitosis are downregulated in NOTCH1 knockout cardiomyocytes. Single-cell transcriptomic analysis reveals abnormal cell lineage determination of cardiac mesoderm, which is manifested by the biased differentiation toward epicardial and second heart field progenitors at the expense of first heart field progenitors in NOTCH1 knockout cell populations. CONCLUSIONS: NOTCH1 is essential for human ventricular-like cardiomyocyte differentiation and proliferation through balancing cell fate determination of cardiac mesoderm and modulating cell cycle progression. Because first heart field progenitors primarily contribute to the left ventricle, we speculate that pathogenic NOTCH1 variants lead to biased differentiation of first heart field progenitors, blocked ventricular-like cardiomyocyte differentiation, and defective cardiomyocyte proliferation, which collaboratively contribute to left ventricular hypoplasia in hypoplastic left heart syndrome.
Subject(s)
Hypoplastic Left Heart Syndrome , Induced Pluripotent Stem Cells , Humans , Endothelial Cells/metabolism , Induced Pluripotent Stem Cells/metabolism , Cell Differentiation/physiology , Myocytes, Cardiac/metabolism , Receptor, Notch1/genetics , Receptor, Notch1/metabolismABSTRACT
Pancreatic ductal adenocarcinoma (PDAC) remains recalcitrant to all forms of cancer treatment and carries a five-year survival rate of only 8%1. Inhibition of oncogenic KRAS (hereafter KRAS*), the earliest lesion in disease development that is present in more than 90% of PDACs, and its signalling surrogates has yielded encouraging preclinical results with experimental agents2-4. However, KRAS*-independent disease recurrence following genetic extinction of Kras* in mouse models anticipates the need for co-extinction strategies5,6. Multiple oncogenic processes are initiated at the cell surface, where KRAS* physically and functionally interacts to direct signalling that is essential for malignant transformation and tumour maintenance. Insights into the complexity of the functional cell-surface-protein repertoire (surfaceome) have been technologically limited until recently and-in the case of PDAC-the genetic control of the function and composition of the PDAC surfaceome in the context of KRAS* signalling remains largely unknown. Here we develop an unbiased, functional target-discovery platform to query KRAS*-dependent changes of the PDAC surfaceome, which reveals syndecan 1 (SDC1, also known as CD138) as a protein that is upregulated at the cell surface by KRAS*. Localization of SDC1 at the cell surface-where it regulates macropinocytosis, an essential metabolic pathway that fuels PDAC cell growth-is essential for disease maintenance and progression. Thus, our study forges a mechanistic link between KRAS* signalling and a targetable molecule driving nutrient salvage pathways in PDAC and validates oncogene-driven surfaceome annotation as a strategy to identify cancer-specific vulnerabilities.
Subject(s)
Carcinoma, Pancreatic Ductal/pathology , Pancreatic Neoplasms/pathology , Pinocytosis , Syndecan-1/metabolism , ADP-Ribosylation Factor 6 , ADP-Ribosylation Factors/metabolism , Animals , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/metabolism , Cell Proliferation , Disease Progression , Female , Guanine Nucleotide Exchange Factors/metabolism , Humans , Male , Mice , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Signal TransductionABSTRACT
We report the clinical description and molecular dissection of a new fatal human inherited disorder characterized by chronic autoinflammation, invasive bacterial infections and muscular amylopectinosis. Patients from two kindreds carried biallelic loss-of-expression and loss-of-function mutations in HOIL1 (RBCK1), a component of the linear ubiquitination chain assembly complex (LUBAC). These mutations resulted in impairment of LUBAC stability. NF-κB activation in response to interleukin 1ß (IL-1ß) was compromised in the patients' fibroblasts. By contrast, the patients' mononuclear leukocytes, particularly monocytes, were hyper-responsive to IL-1ß. The consequences of human HOIL-1 and LUBAC deficiencies for IL-1ß responses thus differed between cell types, consistent with the unique association of autoinflammation and immunodeficiency in these patients. These data suggest that LUBAC regulates NF-κB-dependent IL-1ß responses differently in different cell types.
Subject(s)
Glycogen Storage Disease Type IV/genetics , Hereditary Autoinflammatory Diseases/genetics , Immunologic Deficiency Syndromes/genetics , NF-kappa B/metabolism , Ubiquitin-Protein Ligases/genetics , Bacterial Infections/genetics , Bacterial Infections/immunology , Cell Cycle Proteins/genetics , Cell Line , Fibroblasts/immunology , Fibroblasts/metabolism , Humans , Immunologic Deficiency Syndromes/metabolism , Interleukin-1beta/metabolism , Monocytes/immunology , Monocytes/metabolism , Oligonucleotide Array Sequence Analysis , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/genetics , Repressor Proteins/genetics , Transcription Factors , Ubiquitin-Protein Ligases/deficiency , Ubiquitin-Protein Ligases/metabolism , UbiquitinationABSTRACT
Generally, for adhesive joints, the polar water molecules in humid environments can have a critical effect on the interfacial structures and structural evolution adjacent to the solid substrates. Regarding this, it is still a big challenge to detect and understand the interfacial hygrothermal aging process at the molecular level in real time and in situ. In this study, to trace the interfacial hygrothermal aging process of a classical epoxy formula containing diglycidyl ether of biphenyl A (DGEBA) and 2,2'-(ethylenedioxy) diethylamine (EDDA) with sapphire and fused silica in a typical hygrothermal environment (85 °C and 85% RH), sum frequency generation (SFG) vibrational spectroscopy was used to probe the molecular-level interfacial structural change over the time. The structural evolution dynamics at the buried epoxy/sapphire and epoxy/silica interfaces upon hygrothermal aging were revealed directly in situ. The interfacial delamination during hygrothermal aging was also elucidated from the molecular level. Upon hygrothermal aging, the interfacial CH signals, such as the ones from methyl, methylene, and phenyl groups, decreased significantly and the water OH signals increased substantially, indicating the water molecules had diffused into the interfaces and destroyed the original interactions between the epoxy formula and the substrates. Further analysis indicates that when the integrated signals in the CH range declined to their minimum and leveled off, the interfacial delamination happened. The tensile experiment proved the validity of these spectroscopic experimental results. Our study provides first-hand and molecular-level evidence on a direct correlation between the diffusion of the surrounding water molecules into the interface and the evolution/destruction of the interfacial structures during hygrothermal aging. More importantly, it is proved, SFG can be developed into a powerful tool to noninvasively reveal the local interfacial delamination in real time and in situ under extreme hygrothermal conditions, complemented by the mechanic test.
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INTRODUCTION: Heart failure (HF) is a major global public health concern. The application of machine learning (ML) to identify individuals at high risk and enable early intervention is a promising approach for improving HF prognosis. We aim to systematically evaluate the performance and value of ML models for predicting HF prognosis. METHODS: PubMed, Web of Science, Scopus, and Embase online databases were searched up to April 30, 2023, to identify studies on the use of ML models to predict HF prognosis. HF prognosis primarily encompasses readmission and mortality. The meta-analysis was conducted by MedCalc software. Subgroup analyses include grouping based on types of ML models, time intervals, sample sizes, the number of predictive variables, validation methods, whether to conduct hyperparameter optimization and calibration, data set partitioning methods. RESULTS: A total of 31 studies were included. The most common ML models were random forest, boosting, support vector machine, neural network. The area under the receiver operating characteristic curve (AUC) for predicting HF readmission was 0.675 (95% CI: 0.651-0.699, p < 0.001), and the AUC for predicting HF mortality was 0.790 (95% CI: 0.765-0.816, p < 0.001). Subgroup analyses revealed that models with the prediction time interval of 1 year, sample sizes ≥10,000, the number of predictive variables ≥100, external validation, hyperparameter tuning, calibration adjustment, and data set partitioning using 10-fold cross-validation exhibited favorable performance within their respective subgroups. CONCLUSION: The performance of ML models in predicting HF readmission is relatively poor, while its performance in predicting HF mortality is moderate. The quality of the relevant studies is generally low, it is essential to enhance the predictive capabilities of ML models through targeted improvements in practical applications.
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Arctii Fructus is the dried ripe fruit of Arctium lappa L. (family Asteraceae) and is in the Chinese pharmacopoeia. Previous research showed that the total lignans from Arctii Fructus (TLAF) have pharmacological activities related to diabetes. This study evaluated the acute and chronic (26 weeks) toxicities associated with oral daily administration of TLAF in Sprague-Dawley (SD) rats. An acute-toxicity test showed that TLAF caused 10% mortality at 3,000 mg/kg × 2 (6-h interval), with toxic symptoms, such as dyspnea and tonic convulsions, indicating potential neurotoxicity. A chronic-toxicity study showed no mortality after administration. The no observed adverse-effect level was 1,800 mg/kg (approximately 54 times higher than the human clinical dose) for 26 weeks of TLAF oral administration in SD rats, with toxicity signs of excessive oral and nasal secretions and moist circumferential hair that recovered after TLAF discontinuation. In the toxicokinetic study, the two main components of TLAF, arctigenin plasma level was positively correlated with dose and tended to accumulate after multiple doses. At 1,800 mg/kg, arctiin plasma level increased and tended to accumulate after multiple doses. These results indicated that TLFA has relatively low toxicity and the potential for clinical treatment of diabetes.
Subject(s)
Diabetes Mellitus , Drugs, Chinese Herbal , Lignans , Rats , Humans , Animals , Rats, Sprague-Dawley , Pharmaceutical Preparations , Diabetes Mellitus/drug therapy , Lignans/toxicityABSTRACT
Pellicles are biofilms that form at the air-liquid interface. We demonstrated that specific strains of Escherichia coli formed pellicles in single cultures when cocultured with Carnobacterium maltaromaticum and E. coli O157:H7 but not with Aeromonas australiensis. Therefore, a combination of comparative genomic, mutational, and transcriptome analyses were applied to identify the unique genes in pellicle formation and investigate gene regulation under different growth phases. Here, we report that pellicle-forming strains do not harbor unique genes relative to non-pellicle-forming strains; however, the expression level of biofilm-related genes differed, especially for the genes encoding curli. Further, the regulatory region of curli biosynthesis is phylogenetically different among pellicle- and non-pellicle-forming strains. The disruption on modified cellulose and regulatory region of curli biosynthesis abolished pellicle formation in strains of E. coli. Besides, the addition of quorum sensing molecules (C4-homoserine lactones [C4-HSL]), synthesized by Aeromonas species, to pellicle formers abolished pellicle formation and implied a role of quorum sensing on pellicle formation. The deletion of autoinducer receptor sdiA in E. coli did not restore pellicle formation when cocultured with A. australiensis but modulated expression level of genes for curli and cellulose biosynthesis, resulting in a thinner layer of pellicle. Taken together, this study identified genetic determinants for pellicle formation and characterized the switching between pellicle to surface-associated biofilm in a dual-species environment, facilitating better understanding of the mechanisms for pellicle formation in E. coli and related organisms. IMPORTANCE To date, most attention has focused on biofilm formation on solid surfaces. By comparison, the knowledge on pellicle formation at the air-liquid interface is more limited and few studies document how bacteria decide on whether to form biofilms on solid surfaces or pellicles at the air-liquid interface to the surface-associated biofilms at the bottom. In this report, we characterized the regulation of biofilm-related genes during pellicle formation and document that interspecies communication via quorum sensing contributes to regulating the switch from pellicle to surface-associated biofilm. The discoveries expand the current view of regulatory cascades associated with pellicle formation.
Subject(s)
Aeromonas , Escherichia coli O157 , Biofilms , Aeromonas/metabolism , Escherichia coli O157/physiology , Genomics , Cellulose/metabolismABSTRACT
Magnetic Fe3O4 nanoparticles show promising applications in nanomedicine. However, the saturation magnetization (MS) of Fe3O4 nanoparticles synthesized in laboratory is usually not high enough, which greatly limits their application in drug delivery and magnetic hyperthermia. Here, by accurate hybrid density functional computation, the doping behavior of group III elements (including Al, Ga, and In) and the effects on magnetic and electronic properties are well studied. The results show that the doping behavior depends on the concentration of dopants. Interestingly, appropriate Ga and In doping concentrations can significantly increase the MS of Fe3O4. In addition, the doping of group III elements (Al, Ga and In) into Fe3O4 would not induce any defect states in the band gap but slightly increases the band gap. Our results provide a simple and feasible scheme for increasing the MS of magnetite, which is significant for the applications of Fe3O4 nanoparticles in drug delivery and magnetic hyperthermia.
ABSTRACT
INTRODUCTION: The susceptibility to surgical site occurrence (SSO) is high following ventral hernia repair (VHR) surgery. SSO severely increases the physical and mental burden on patients. The main purpose of this review was to analyze the efficacy of negative pressure wound therapy (NPWT) after open VHR(OVHR) and explore benefits to patients. METHODS: The Cochrane Library, PubMed, and Embase databases were searched from the date of establishment to 15 October 2022. All randomized controlled trials and retrospective cohort studies comparing NPWT with standard dressings after OVHR were included. The Revman 5.4 software recommended by Cochrane and the STATA16 software were used in this meta-analysis. RESULTS: Fifteen studies (involving 1666 patients) were identified and included in the meta-analysis, with 821 patients receiving NPWT. Overall, the incidence rate of SSO in the NPWT group was lower compared to the control group (odds ratio [OR] = 0.44; 95% confidence interval [CI] = 0.21-0.93; I2 = 86%; P = 0.03). The occurrence rate of surgical site infection (SSI; OR = 0.51; 95% CI = 0.38-0.68, P < 0.001), wound dehiscence (OR = 0.64; 95% CI = 0. 43-0.96; P = 0.03), and hernia recurrence (OR = 0.51; 95% CI = 0.28-0.91, P = 0.02) was also lowered. There was no significant difference in seroma (OR = 0.76; 95% CI = 0.54-1.06; P = 0.11), hematoma (OR = 0.53; 95% CI = 0.25-1.11; P = 0.09), or skin necrosis (OR = 0.83; 95% CI = 0.47-1.46; P = 0.52). CONCLUSION: NPWT can effectively decrease the occurrence of SSO, SSI wound dehiscence and hernia recurrence and should be considered following OVHR.
Subject(s)
Hernia, Ventral , Negative-Pressure Wound Therapy , Humans , Surgical Wound Dehiscence/etiology , Retrospective Studies , Negative-Pressure Wound Therapy/adverse effects , Surgical Wound Infection/epidemiology , Surgical Wound Infection/prevention & control , Surgical Wound Infection/etiology , Hernia, Ventral/surgery , Herniorrhaphy/adverse effectsABSTRACT
BACKGROUND: Influenza immunization during pregnancy provides protection to the mother and the infant. Studies in adults and children with inactivated influenza vaccine have identified changes in immune gene expression that were correlated with antibody responses. The current study was performed to define baseline blood transcriptional profiles and changes induced by inactivated influenza vaccine in pregnant women and to identify correlates with antibody responses. METHODS: Pregnant women were immunized with inactivated influenza vaccine during the 2013-2014 and 2014-2015 seasons. Blood samples were collected on day 0 (before vaccination) and on days 1 and 7 after vaccination for transcriptional profile analyses, and on days 0 and 30, along with delivery and cord blood samples, to measure antibody titers. RESULTS: Transcriptional analysis demonstrated overexpression of interferon-stimulated genes (ISGs) on day 1 and of plasma cell genes on day 7. Prevaccination ISG expression and ISGs overexpressed on day 1 were significantly correlated with increased H3N2, B Yamagata, and B Victoria antibody titers. Plasma cell gene expression on day 7 was correlated with increased B Yamagata and B Victoria antibody titers. Compared with women who were vaccinated during the previous influenza season, those who were not showed more frequent significant correlations between ISGs and antibody titers. CONCLUSIONS: Influenza vaccination in pregnant women resulted in enhanced expression of ISGs and plasma cell genes correlated with antibody responses. Brief summary: This study identified gene expression profiles of interferon-stimulated genes and plasma cells before vaccination and early after vaccination that were correlated with antibody responses in pregnant women vaccinated for influenza.
Subject(s)
Antibodies, Viral/blood , Blood Group Antigens , Influenza Vaccines/administration & dosage , Influenza, Human/prevention & control , Interferons/genetics , Antibody Formation , Antiviral Agents/therapeutic use , Female , Gene Expression Profiling , Humans , Influenza A Virus, H3N2 Subtype/immunology , Influenza Vaccines/immunology , Influenza, Human/immunology , Pregnancy , Pregnant Women , Transcriptome , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/immunologyABSTRACT
BACKGROUND: The interplay among respiratory syncytial virus (RSV) loads, mucosal interferons (IFN), and disease severity in RSV-infected children is poorly understood. METHODS: Children <2 years of age with mild (outpatients) or severe (inpatients) RSV infection and healthy controls were enrolled, and nasopharyngeal samples obtained for RSV loads and innate cytokines quantification. Patients were stratified by age (0-6 and >6-24 months) and multivariable analyses performed to identify predictors of disease severity. RESULTS: In 2015-2019 we enrolled 219 RSV-infected children (78 outpatients; 141 inpatients) and 34 healthy controls. Type I, II, and III IFN concentrations were higher in children aged >6 versus 0-6 months and, like CXCL10, they were higher in outpatients than inpatients and correlated with RSV loads (P < .05). Higher IL6 concentrations increased the odds of hospitalization (odds ratio [OR], 2.30; 95% confidence interval [CI], 1.07-5.36) only in children >6 months, while higher IFN-λ2/3 concentrations had the opposite effect irrespective of age (OR, 0.38; 95% CI, .15-.86). Likewise, higher CXCL10 concentrations decreased the odds of hospitalization (OR, 0.21; 95% CI, .08-.48), oxygen administration (OR, 0.42; 95% CI, .21-.80),PICU admission (OR, 0.39; 95% CI, .20-.73), and prolonged hospitalization (OR, 0.57; 95% CI, .32-.98) irrespective of age. CONCLUSIONS: Children with milder RSV infection and those aged >6 months had higher concentrations of mucosal IFNs, suggesting that maturation of mucosal IFN responses are associated with protection against severe RSV disease.
Subject(s)
Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus, Human , Humans , Child , Infant , Child, Preschool , Interferon Lambda , Viral Load , Patient AcuityABSTRACT
BACKGROUND: Corticosteroids remain a key therapy for treating children with asthma. Patients with severe asthma are insensitive, resistant, or refractory to corticosteroids and have poorly controlled symptoms that involve airway inflammation, airflow obstruction, and frequent exacerbations. While the pathways that mediate corticosteroid insensitivity in asthma remain poorly defined, recent studies suggest that enhanced Th1 pathways, mediated by TNFα and IFNγ, may play a role. We previously reported that the combined effects of TNFα and IFNγ promote corticosteroid insensitivity in developing human airway smooth muscle (ASM). METHODS: To further understand the effects of TNFα and IFNγ on corticosteroid sensitivity in the context of neonatal and pediatric asthma, we performed RNA sequencing (RNA-seq) on human pediatric ASM treated with fluticasone propionate (FP), TNFα, and/or IFNγ. RESULTS: We found that TNFα had a greater effect on gene expression (~ 1000 differentially expressed genes) than IFNγ (~ 500 differentially expressed genes). Pathway and transcription factor analyses revealed enrichment of several pro-inflammatory responses and signaling pathways. Interestingly, treatment with TNFα and IFNγ augmented gene expression with more than 4000 differentially expressed genes. Effects of TNFα and IFNγ enhanced several pro-inflammatory genes and pathways related to ASM and its contributions to asthma pathogenesis, which persisted in the presence of corticosteroids. Co-expression analysis revealed several gene networks related to TNFα- and IFNγ-mediated signaling, pro-inflammatory mediator production, and smooth muscle contractility. Many of the co-expression network hubs were associated with genes that are insensitive to corticosteroids. CONCLUSIONS: Together, these novel studies show the combined effects of TNFα and IFNγ on pediatric ASM and implicate Th1-associated cytokines in promoting ASM inflammation and hypercontractility in severe asthma.
Subject(s)
Asthma , Interferon-gamma , Tumor Necrosis Factor-alpha , Adrenal Cortex Hormones/pharmacology , Adrenal Cortex Hormones/therapeutic use , Asthma/drug therapy , Asthma/genetics , Asthma/metabolism , Child , Gene Expression , Humans , Infant, Newborn , Inflammation/metabolism , Interferon-gamma/metabolism , Lung/metabolism , Muscle, Smooth , Myocytes, Smooth Muscle/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
Interfacial bonding strength of an epoxy-based adhesive depends on the interfacial interaction between the adhesive and the substrate. Normally, the curing process at the interface accompanied by the interfacial bonding formation is different from that in the bulk, and it is still a big challenge to probe the interfacial bonding formation at a molecular level. In this study, to trace the interfacial structural evolution of a representative formula of epoxy (digylcidyl ether of biphenyl A, DGEBA) and amine hardener [1,2-bis(2-aminoethoxy)ethane, EDDA] with the sapphire and silica substrates upon curing and post-curing steps, sum frequency generation (SFG) vibrational spectroscopy is employed to detect the molecular-level interfacial structural information. For the sapphire substrate, upon curing, backbone methylene (CH2) stretching signals decrease, indicating the formation of a rigid chain network structure and thus losing the local methylene order, while vibrational signals of the sapphire surface hydroxyl (OH) groups (including hydrogen-bonded and unbonded) increase significantly, indicating the formation of a strong hydrogen-bonding and polar interaction between the epoxy adhesive and the sapphire surface. Upon post-curing, increased backbone CH2 signals and decreased sapphire OH signals suggest interfacial chemical bonding formation due to the reaction between the epoxy rings and the sapphire surface OH groups. Orientation analysis confirms the enhanced ordering of the sapphire surface OH groups upon curing and post-curing, in comparison to the uncured epoxy formula. As for the fused silica, weak vibrational signals of the methylene (CH2) and methyl (CH3) groups are observed before curing, while both of them increase slightly for the cured and post-cured epoxy formulae, suggesting relatively less hydrophilic nature of the silica surface compared to that of the sapphire surface, also evidenced by the very weak OH signals upon curing and post-curing. Further measurement on the adhesion strength matches up with the above spectroscopic experimental results, substantiating the correlation between the macroscopic bonding strength of the epoxy adhesive and the microscopic molecular-level structure.
ABSTRACT
The formation of the interfacial adhesion between an epoxy adhesive and a substrate was normally accompanied by the epoxy curing process on the substrate. Although the debate on the formation mechanism of the interfacial adhesion is still ongoing, this issue can causally be resolved by studying the interfacial structural formation between the epoxy adhesive and the substrate. Herein, to reveal the interfacial structural formation of a representative formula composed of epoxy (digylcidyl ether of biphenyl A, DGEBA) and amine hardener (2,2'-(ethylenedioxy) diethylamine, EDDA) with the steel substrate upon curing and postcuring treatments, sum-frequency generation (SFG) vibrational spectroscopy with a sandwiched transparent window/epoxy adhesive/steel setup was applied to detect and track the buried molecular-level structures at the epoxy adhesive/steel interface. An X-ray photoelectron spectroscopic (XPS) experiment was performed to probe the intentionally exposed interface to disclose the occurring interfacial chemical reaction. The reaction between the epoxy groups and the steel-surface OH groups and the molecular reconstruction of interfacial epoxy methyl groups upon curing and postcuring steps were confirmed. The latter also indirectly indicated the formation of the additional hydrogen bonding and the former bonding reaction at the interface. The above two spectroscopic experimental results matched up with the further examination of the adhesion strength. Therefore, this work elucidates the formation of the interfacial bonding between the epoxy formula and the steel substrate upon curing and postcuring treatments at the molecular level, thus providing an in-depth insight into the origin of the interfacial adhesion.
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INTRODUCTION: The total lignans from Fructus arctii (TLFA) is a mixture of a series of lignans isolated from dried ripe fruit of Arctium lappa L. We previously reported on the pharmacological activity of TLFA that is related to diabetes. An accurate and practical TLFA quantitative analysis method for utilising it needs to be established. OBJECTIVE: This study aimed to develop an effective quantitative analysis method for assessing the TLFA quality. METHODS: A total of 11 marker components were confirmed by analysing the high-performance liquid chromatography fingerprints of 24 batches of TLFA samples. The samples were prepared from TLFA and structurally identified as lappaol H, lappaol C, arctiin, arctignan D, arctignan E, matairesinol, arctignan G, isolappaol A, lappaol A, arctigenin, and lappaol F. In the quantitative analysis of multi-components by the single-marker (QAMS) method and with arctiin as an internal reference substance, the content of these lignans in TLFA was simultaneously determined according to their relative correction factors with arctiin. RESULTS: There was no significant difference between results measured by the QAMS and traditional external standard methods. Hierarchical cluster and principal component analyses were performed to evaluate 24 TLFA batches based on the contents of 10 marker components. The results revealed that QAMS method combined with chemometric analyses could accurately measure and clearly distinguish the different quality samples of TLFA. CONCLUSION: The QAMS method is a reliable and promising quality control method for TLFA. It can provide a reference for promoting quality control of complex multi-component systems, especially for traditional Chinese medicine.
Subject(s)
Arctium , Drugs, Chinese Herbal , Lignans , Chromatography, High Pressure Liquid/methods , Fruit/chemistry , Lignans/analysis , Arctium/chemistry , Quality Control , Drugs, Chinese Herbal/chemistryABSTRACT
Capnophilic lactic fermentation (CLF) is an anaplerotic pathway exclusively identified in the anaerobic hyperthermophilic bacterium Thermotoga neapolitana, a member of the order Thermotogales. The CO2-activated pathway enables non-competitive synthesis of hydrogen and L-lactic acid at high yields, making it an economically attractive process for bioenergy production. In this work, we discovered and characterized CLF in Thermotoga sp. strain RQ7, a naturally competent strain, opening a new avenue for molecular investigation of the pathway. Evaluation of the fermentation products and expression analyses of key CLF-genes by RT-PCR revealed similar CLF-phenotypes between T. neapolitana and T. sp. strain RQ7, which were absent in the non-CLF-performing strain T. maritima. Key CLF enzymes, such as PFOR, HYD, LDH, RNF, and NFN, are up-regulated in the two CLF strains. Another important finding is the up-regulation of V-ATPase, which couples ATP hydrolysis to proton transport across the membranes, in the two CLF-performing strains. The fact that V-ATPase is absent in T. maritima suggested that this enzyme plays a key role in maintaining the necessary proton gradient to support high demand of reducing equivalents for simultaneous hydrogen and lactic acid synthesis in CLF.
Subject(s)
Carbon Dioxide , Thermotoga , Adenosine Triphosphatases/metabolism , Adenosine Triphosphate/metabolism , Anaerobiosis , Archaea/metabolism , Base Composition , Carbon Dioxide/metabolism , Fermentation , Hydrogen/metabolism , Lactic Acid/metabolism , Phylogeny , Protons , RNA, Ribosomal, 16S/metabolism , Sequence Analysis, DNAABSTRACT
Background: Surgery is the mainstay of treatment for gastric gastrointestinal stromal tumours (GIST). However, the choice of surgical approach for gastric GIST remains controversial. Aims and Objectives: To evaluate the short- and long-term efficacies of laparoscopic surgery versus conventional open surgery for gastric GIST. Materials and Methods: We retrospectively reviewed 148 patients with gastric GIST at our hospital between January 2013 and January 2020. The patients were categorised into the following two groups based on the surgery performed: The laparoscopic surgery group (LG) and the open surgery group (OG). Differences in the tumour size, surgical procedures and modified National Institutes of Health classification were statistically significant. To balance the intergroup confounders, we performed 1:1 propensity score matching (PSM). Results: A total of 104 patients were selected after PSM (52 in each group). We focused on the short- and long- term outcomes of patients. The baseline information was balanced between the two groups after PSM. The LG benefited from the advantages of a minimally invasive surgery (faster gastrointestinal function recovery, shorter time to drainage tube removal, less blood loss and shorter hospitalisation period), however, it also had high treatment costs. Moreover, both laparoscopic and open surgeries resulted in similar intra-operative and post-operative complications rates, overall survival time and disease-free survival time. Conclusion: Laparoscopic resection is feasible and oncologically safe for GIST. However, more prospective studies are required to confirm the findings.
ABSTRACT
The glasses-free three dimensional(3D) endoscopic display system provides the surgeon with the depth information of the minimally invasive surgery scene obtained from the binocular perspective, which can effectively relieve the surgeon's posture fatigue and visual fatigue during the long-term surgery, and assist in the operation of surgical instruments more accurately to reduce the damage to the surrounding tissues of the operation area. However, the glasses-free 3D display device currently has the problem of a narrow optimal viewing zone and easy crosstalk, especially in the surgical teaching application scenario, which performs poorly. In order to overcome the limitation of the narrower field of view, we introduce deep learning algorithms to detect and locate multiple faces, fine-tune the 3D display grating of the endoscope, rearrange pixels, and change the best view area, so that more people can get the best view. The experimental results show that the face detection accuracy of the method is 97.88%, and the detection time is 135 frames/ms, which achieves high accuracy while maintaining real-time performance.
Subject(s)
Endoscopes , Endoscopy , Humans , Imaging, Three-Dimensional , Minimally Invasive Surgical Procedures , Surgical InstrumentsABSTRACT
OBJECTIVE: Surgical site infection (SSI) in colorectal cancer (CRC) has been a serious health care problem due to the delay of postoperative recovery. Our present study aimed to explore the risk factors for SSI in CRC patients. METHODOLOGY: We have systematically searched these databases: PubMed, Cochrane Library, and EMBASE as of March 2020 for studies on risk factors associated with SSI. Two investigators independently conducted the quality assessment and data extraction. Related risk factors in the studies were recorded, and a meta-analysis was performed. RESULTS: The search initially provided 2262 hits, 1913 studies were screened by two independent investigators. Finally, 15 studies were identified to be relevant for this meta-analysis. In total, 25 risk factors were eligible. Our meta-analysis indicated that eight factors (obesity, male sex, diabetes mellitus, ASA score ≥ 3, stoma creation, intraoperative complications, perioperative blood transfusion, and operation time ≥ 180 min) were significant risk factors for SSI, and one factor (laparoscopic procedure) was protective for SSI. CONCLUSIONS: Effective interventions targeting the above factors may reduce the risk of developing postoperative SSI in CRC patients and improve the clinical outcome of patients. Further prospective studies are needed to confirm these findings.