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1.
Brief Bioinform ; 24(2)2023 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-36702751

RESUMO

Recognizing binding sites of DNA-binding proteins is a key factor for elucidating transcriptional regulation in organisms. ChIP-exo enables researchers to delineate genome-wide binding landscapes of DNA-binding proteins with near single base-pair resolution. However, the peak calling step hinders ChIP-exo application since the published algorithms tend to generate false-positive and false-negative predictions. Here, we report the development of DEOCSU (DEep-learning Optimized ChIP-exo peak calling SUite), a novel machine learning-based ChIP-exo peak calling suite. DEOCSU entails the deep convolutional neural network model which was trained with curated ChIP-exo peak data to distinguish the visualized data of bona fide peaks from false ones. Performance validation of the trained deep-learning model indicated its high accuracy, high precision and high recall of over 95%. Applying the new suite to both in-house and publicly available ChIP-exo datasets obtained from bacteria, eukaryotes and archaea revealed an accurate prediction of peaks containing canonical motifs, highlighting the versatility and efficiency of DEOCSU. Furthermore, DEOCSU can be executed on a cloud computing platform or the local environment. With visualization software included in the suite, adjustable options such as the threshold of peak probability, and iterable updating of the pre-trained model, DEOCSU can be optimized for users' specific needs.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Aprendizado Profundo , Imunoprecipitação da Cromatina , Proteínas de Ligação a DNA/metabolismo , Software , Algoritmos , Sítios de Ligação , Análise de Sequência de DNA
2.
Nucleic Acids Res ; 51(8): 3618-3630, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37026477

RESUMO

While global transcription factors (TFs) have been studied extensively in Escherichia coli model strains, conservation and diversity in TF regulation between strains is still unknown. Here we use a combination of ChIP-exo-to define ferric uptake regulator (Fur) binding sites-and differential gene expression-to define the Fur regulon in nine E. coli strains. We then define a pan-regulon consisting of 469 target genes that includes all Fur target genes in all nine strains. The pan-regulon is then divided into the core regulon (target genes found in all the strains, n = 36), the accessory regulon (target found in two to eight strains, n = 158) and the unique regulon (target genes found in one strain, n = 275). Thus, there is a small set of Fur regulated genes common to all nine strains, but a large number of regulatory targets unique to a particular strain. Many of the unique regulatory targets are genes unique to that strain. This first-established pan-regulon reveals a common core of conserved regulatory targets and significant diversity in transcriptional regulation amongst E. coli strains, reflecting diverse niche specification and strain history.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Regulon , Proteínas Repressoras , Escherichia coli/genética , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Ferro/metabolismo , Regulon/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fatores de Transcrição
3.
Nucleic Acids Res ; 51(19): 10176-10193, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37713610

RESUMO

Transcriptomic data is accumulating rapidly; thus, scalable methods for extracting knowledge from this data are critical. Here, we assembled a top-down expression and regulation knowledge base for Escherichia coli. The expression component is a 1035-sample, high-quality RNA-seq compendium consisting of data generated in our lab using a single experimental protocol. The compendium contains diverse growth conditions, including: 9 media; 39 supplements, including antibiotics; 42 heterologous proteins; and 76 gene knockouts. Using this resource, we elucidated global expression patterns. We used machine learning to extract 201 modules that account for 86% of known regulatory interactions, creating the regulatory component. With these modules, we identified two novel regulons and quantified systems-level regulatory responses. We also integrated 1675 curated, publicly-available transcriptomes into the resource. We demonstrated workflows for analyzing new data against this knowledge base via deconstruction of regulation during aerobic transition. This resource illuminates the E. coli transcriptome at scale and provides a blueprint for top-down transcriptomic analysis of non-model organisms.


Assuntos
Escherichia coli , Bases de Conhecimento , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Transcriptoma
4.
J Biol Chem ; 299(1): 102761, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36463964

RESUMO

Pathogenic species from the Mycobacterium genus are responsible for a number of adverse health conditions in humans and animals that threaten health security and the economy worldwide. Mycobacteria have up to five specialized secretion systems (ESX-1 to ESX-5) that transport virulence factors across their complex cell envelope to facilitate manipulation of their environment. In pathogenic species, these virulence factors influence the immune system's response and are responsible for membrane disruption and contributing to cell death. While structural details of these secretion systems have been recently described, gaps still remain in the structural understanding of the secretion mechanisms of most substrates. Here, we describe the crystal structure of Mycobacterium tuberculosis ESX-1 secretion-associated substrate EspB bound to its chaperone EspK. We found that EspB interacts with the C-terminal domain of EspK through its helical tip. Furthermore, cryogenic electron microscopy, size exclusion chromatography analysis, and small-angle X-ray scattering experiments show that EspK keeps EspB in its secretion-competent monomeric form and prevents its oligomerization. The structure presented in this study suggests an additional secretion mechanism in ESX-1, analogous to the chaperoning of proline-glutamate (PE)-proline-proline-glutamate (PPE) proteins by EspG, where EspK facilitates the secretion of EspB in Mycobacterium species.


Assuntos
Proteínas da Membrana Bacteriana Externa , Proteínas de Bactérias , Mycobacterium tuberculosis , Fatores de Virulência , Humanos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Glutamatos/metabolismo , Mycobacterium tuberculosis/metabolismo , Prolina/metabolismo , Fatores de Virulência/química , Fatores de Virulência/metabolismo , Morte Celular , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/metabolismo , Cristalização , Microscopia Crioeletrônica
5.
Scand J Gastroenterol ; 59(6): 698-709, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38466190

RESUMO

Oesophageal squamous cell carcinoma (ESCC) is a common malignant tumour of the gastrointestinal tract. Early detection and access to appropriate treatment are crucial for the long-term survival of patients. However, limited diagnostic and monitoring methods are available for identifying early stage ESCC. Endoscopic screening and surgical resection are commonly used to diagnose and treat early ESCC. However, these methods have disadvantages, such as high recurrence, lethality, and mortality rates. Therefore, methods to improve early diagnosis of ESCC and reduce its mortality rate are urgently required. In 1961, Gary et al. proposed a novel liquid biopsy approach for clinical diagnosis. This involved examining exosomes, circulating tumour cells, circulating free DNA, and circulating free RNA in body fluids. The ability of liquid biopsy to obtain samples repeatedly, wide detection range, and fast detection speed make it a feasible option for non-invasive tumour detection. In clinical practice, liquid biopsy technology has gained popularity for early screening, diagnosis, treatment efficacy monitoring, and prognosis assessment. Thus, this is a highly promising examination method. However, there have been no comprehensive reviews on the four factors of liquid biopsy in the context of ESCC. This review aimed to analyse the progress of liquid biopsy research for ESCC, including its classification, components, and potential future applications.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Biópsia Líquida/métodos , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/diagnóstico , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas do Esôfago/terapia , Prognóstico , Detecção Precoce de Câncer/métodos , Células Neoplásicas Circulantes/patologia , Biomarcadores Tumorais/sangue , Exossomos
6.
Nucleic Acids Res ; 50(D1): D1077-D1084, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34791440

RESUMO

The transcriptional regulatory network in prokaryotes controls global gene expression mostly through transcription factors (TFs), which are DNA-binding proteins. Chromatin immunoprecipitation (ChIP) with DNA sequencing methods can identify TF binding sites across the genome, providing a bottom-up, mechanistic understanding of how gene expression is regulated. ChIP provides indispensable evidence toward the goal of acquiring a comprehensive understanding of cellular adaptation and regulation, including condition-specificity. ChIP-derived data's importance and labor-intensiveness motivate its broad dissemination and reuse, which is currently an unmet need in the prokaryotic domain. To fill this gap, we present proChIPdb (prochipdb.org), an information-rich, interactive web database. This website collects public ChIP-seq/-exo data across several prokaryotes and presents them in dashboards that include curated binding sites, nucleotide-resolution genome viewers, and summary plots such as motif enrichment sequence logos. Users can search for TFs of interest or their target genes, download all data, dashboards, and visuals, and follow external links to understand regulons through biological databases and the literature. This initial release of proChIPdb covers diverse organisms, including most major TFs of Escherichia coli, and can be expanded to support regulon discovery across the prokaryotic domain.


Assuntos
Imunoprecipitação da Cromatina , Cromatina/genética , Bases de Dados Genéticas , Fatores de Transcrição/genética , Sítios de Ligação/genética , Cromatina/classificação , Genoma/genética , Células Procarióticas , Ligação Proteica/genética
7.
Proc Natl Acad Sci U S A ; 118(2)2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33372147

RESUMO

A transcription factor (TF) is a sequence-specific DNA-binding protein that modulates the transcription of a set of particular genes, and thus regulates gene expression in the cell. TFs have commonly been predicted by analyzing sequence homology with the DNA-binding domains of TFs already characterized. Thus, TFs that do not show homologies with the reported ones are difficult to predict. Here we report the development of a deep learning-based tool, DeepTFactor, that predicts whether a protein in question is a TF. DeepTFactor uses a convolutional neural network to extract features of a protein. It showed high performance in predicting TFs of both eukaryotic and prokaryotic origins, resulting in F1 scores of 0.8154 and 0.8000, respectively. Analysis of the gradients of prediction score with respect to input suggested that DeepTFactor detects DNA-binding domains and other latent features for TF prediction. DeepTFactor predicted 332 candidate TFs in Escherichia coli K-12 MG1655. Among them, 84 candidate TFs belong to the y-ome, which is a collection of genes that lack experimental evidence of function. We experimentally validated the results of DeepTFactor prediction by further characterizing genome-wide binding sites of three predicted TFs, YqhC, YiaU, and YahB. Furthermore, we made available the list of 4,674,808 TFs predicted from 73,873,012 protein sequences in 48,346 genomes. DeepTFactor will serve as a useful tool for predicting TFs, which is necessary for understanding the regulatory systems of organisms of interest. We provide DeepTFactor as a stand-alone program, available at https://bitbucket.org/kaistsystemsbiology/deeptfactor.


Assuntos
Biologia Computacional/métodos , Previsões/métodos , Fatores de Transcrição/genética , Algoritmos , Sítios de Ligação/genética , Sequenciamento de Cromatina por Imunoprecipitação/métodos , DNA/genética , Proteínas de Ligação a DNA/genética , Aprendizado Profundo/tendências , Genoma/genética , Ligação Proteica/genética , Software
8.
Mol Genet Genomics ; 298(6): 1321-1330, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37498358

RESUMO

The Datong Basin was an important arena for population movement and admixture between the Yellow River Valley and Eastern Steppe. In historical materials, the region was often the setting for a tug-of-war between Han farmers and non-Han nomads. The genetic makeup and population history of this Datong population has, however, remained uncertain. In this study, we analysed 289 mitogenomes from Datong individuals. Our primary findings were: (1) population summary statistics analysis revealed a high level of genetic diversity and strong signals of population expansion in the Datong population; (2) inter-population comparisons (PCA and Fst heatmap) exhibited a close clustering between the Datong population and Northern Han, especially northern frontier groups, such as the Inner Mongolia Han, Heilongjiang Han, Liaoning Han and Tianjin Han; (3) phylogeographic analysis of complete mitogenomes revealed the presence of different components in the maternal gene pools of Datong population-the northern East Asian component was dominant (66.44%), whereas the southern East Asians were the second largest component with 31.49%. We also observed a much reduced west Eurasian (2.07%) component; (4) direct comparisons with ancient groups showed closer relationship between Datong and Yellow River farmers than Eastern Steppe nomads. Despite, therefore, centuries of Eastern Steppe nomadic control over the Datong area, Yellow River farmers had a much more significant impact on the Datong population.


Assuntos
Genoma Mitocondrial , Humanos , Genoma Mitocondrial/genética , Rios , Filogeografia , Povo Asiático , China , Genética Populacional , DNA Mitocondrial/genética
9.
J Transl Med ; 21(1): 293, 2023 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-37121999

RESUMO

BACKGROUND: Acute lung injury (ALI) is a common and serious complication of sepsis with high mortality. Ferroptosis, categorized as programmed cell death, contributes to the development of lung injury. Protectin conjugates in tissue regeneration 1 (PCTR1) is an endogenous lipid mediator that exerts protective effects against multiorgan injury. However, the role of PCTR1 in the ferroptosis of sepsis-related ALI remains unknown. METHODS: A pulmonary epithelial cell line and a mouse model of ALI stimulated with lipopolysaccharide (LPS) were established in vitro and in vivo. Ferroptosis biomarkers, including ferrous (Fe2+), glutathione (GSH), malondialdehyde (MDA) and 4-Hydroxynonenal (4-HNE), were assessed by relevant assay kits. Glutathione peroxidase 4 (GPX4) and prostaglandin-endoperoxide synthase 2 (PTGS2) protein levels were determined by western blotting. Lipid peroxides were examined by fluorescence microscopy and flow cytometry. Cell viability was determined by a CCK-8 assay kit. The ultrastructure of mitochondria was observed with transmission electron microscopy. Morphology and inflammatory cytokine levels predicted the severity of lung injury. Afterward, related inhibitors were used to explore the potential mechanism by which PCTR1 regulates ferroptosis. RESULTS: PCTR1 treatment protected mice from LPS-induced lung injury, which was consistent with the effect of the ferroptosis inhibitor ferrostatin-1. PCTR1 treatment decreased Fe2+, PTGS2 and lipid reactive oxygen species (ROS) contents, increased GSH and GPX4 levels and ameliorated mitochondrial ultrastructural injury. Administration of LPS or the ferroptosis agonist RSL3 resulted in reduced cell viability, which was rescued by PCTR1. Mechanistically, inhibition of the PCTR1 receptor lipoxin A4 (ALX), protein kinase A (PKA) and transcription factor cAMP-response element binding protein (CREB) partly decreased PCTR1 upregulated GPX4 expression and a CREB inhibitor blocked the effects ofPCTR1 on ferroptosis inhibition and lung protection. CONCLUSION: This study suggests that PCTR1 suppresses LPS-induced ferroptosis via the ALX/PKA/CREB signaling pathway, which may offer promising therapeutic prospects in sepsis-related ALI.


Assuntos
Lesão Pulmonar Aguda , Ferroptose , Sepse , Animais , Camundongos , Antígenos CD59 , Ciclo-Oxigenase 2 , Lipopolissacarídeos/farmacologia , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/etiologia , Sepse/complicações , Fator 2 Ativador da Transcrição
10.
Nanotechnology ; 34(20)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36780666

RESUMO

Low quantum efficiency and serious photogenerated carrier recombination have been urgent bottleneck problems for photocatalytic materials. Herein, we prepared Nb, Se-codoped ZnIn2S4/NbSe2composites through a facile solvothermal method. The synergetic effect of codoping and cocatalyst was investigated on the photodegradation performance towards tetracycline under visible-light irradiation. By adjusting the final composition, the comprehensive characterization revealed that the optimum degradation efficiency of NS/ZIS-1.6 catalyst arrived at 75% in 70 min, which was 5.8 times higher than that of pure ZnIn2S4. Deep analysis indicated that the enhanced photocatalytic performance could be attributed to higher light absorption, more efficient electron/hole separation, faster charge transport, and lower carrier recombination. This work may offer novel viewpoint for design of high-performance catalysts towards the visible-light-driven photodegradation system.

11.
Epidemiol Infect ; 151: e94, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37203184

RESUMO

This study aimed to determine the impact of current hepatitis B virus (HBV) infection on patients hospitalised with sepsis. This was a retrospective cohort study. Patients from three medical centres in Suzhou from 10 January 2016 to 23 July 2022 participated in this study. Demographic characteristics and clinical characteristics were collected. A total of 945 adult patients with sepsis were included. The median age was 66.0 years, 68.6% were male, 13.1% presented with current HBV infection, and 34.9% of all patients died. In the multivariable-adjusted Cox model, patients with current HBV infection had significantly higher mortality than those without (hazard ratio (HR) 1.50, 95% confidence interval (CI) 1.11-2.02). A subgroup analysis showed that being infected with HBV significantly increased in-hospital mortality in patients younger than 65 years old (HR 1.74, 95% CI 1.16-2.63), whereas no significant impact was observed in patients ≥65 years. The propensity score-matched case-control analysis showed that the rate of septic shock (91.4% vs. 62.1%, P < 0.001) and in-hospital mortality (48.3% vs. 35.3%, P = 0.045) were much higher in the propensity score-matched HBV infection group compared with the control group. In conclusion, current HBV infection was associated with mortality in adults with sepsis.


Assuntos
Hepatite B , Sepse , Adulto , Humanos , Masculino , Idoso , Feminino , Vírus da Hepatite B , Estudos Retrospectivos , Hepatite B/complicações , Hepatite B/epidemiologia , Antígenos de Superfície da Hepatite B
12.
J Biochem Mol Toxicol ; 37(4): e23293, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36541402

RESUMO

Multiple circular RNAs (circRNAs) were proven to regulate the development of pancreatic cancer. However, the action of circ_0018909 in pancreatic cancer was still unclear. The expression of circ_0018909, microRNA-545-3p (miR-545-3p), and fatty acid synthase (FASN) was measured using quantitative reverse-transcriptase PCR (qRT-PCR). Cell growth, cell cycle arrest, apoptotic cells, metastasis, and epithelial to mesenchymal transition (EMT) were determined using EdU assay, flow cytometry, wound-healing assay, transwell invasion, and western blotting, respectively. The expression of the macrophage markers, including CD80, MCP-1, iNOS, and IL-6 (M1 markers), as well as CD206 and CD163 (M2 markers), was analyzed using qRT-PCR. Circ_0018909 knockdown dramatically depressed cell growth, migration, invasion, EMT, and elevated the number of apoptotic cells in pancreatic cancer cells, and repressed tumor growth in mice. Moreover, we proved that the absence of miR-545-3p rescued the action of circ_0018909 downregulation on cell growth, metastasis, apoptosis, and EMT in pancreatic cancer cells. MiR-545-3p bound to FASN and FASN overexpression hindered the impacts of miR-545-3p on the progression of pancreatic cancer. Besides this, our data demonstrated that circ_0018909 induced polarization from M0 macrophages to M2 macrophages. Circ_0018909 knockdown retarded the development of pancreatic cancer by modulating miR-545-3p to regulate FASN expression.


Assuntos
MicroRNAs , Neoplasias Pancreáticas , Animais , Camundongos , Transição Epitelial-Mesenquimal , Ácido Graxo Sintases , Neoplasias Pancreáticas/genética , Proliferação de Células , MicroRNAs/genética , Linhagem Celular Tumoral , Neoplasias Pancreáticas
13.
Nucleic Acids Res ; 49(17): 9696-9710, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34428301

RESUMO

Bacteria regulate gene expression to adapt to changing environments through transcriptional regulatory networks (TRNs). Although extensively studied, no TRN is fully characterized since the identity and activity of all the transcriptional regulators comprising a TRN are not known. Here, we experimentally evaluate 40 uncharacterized proteins in Escherichia coli K-12 MG1655, which were computationally predicted to be transcription factors (TFs). First, we used a multiplexed chromatin immunoprecipitation method combined with lambda exonuclease digestion (multiplexed ChIP-exo) assay to characterize binding sites for these candidate TFs; 34 of them were found to be DNA-binding proteins. We then compared the relative location between binding sites and RNA polymerase (RNAP). We found 48% (283/588) overlap between the TFs and RNAP. Finally, we used these data to infer potential functions for 10 of the 34 TFs with validated DNA binding sites and consensus binding motifs. Taken together, this study: (i) significantly expands the number of confirmed TFs to 276, close to the estimated total of about 280 TFs; (ii) provides putative functions for the newly discovered TFs and (iii) confirms the functions of four representative TFs through mutant phenotypes.


Assuntos
Escherichia coli K12/genética , Proteínas de Escherichia coli/metabolismo , Fatores de Transcrição/metabolismo , Sítios de Ligação , Sequenciamento de Cromatina por Imunoprecipitação , Escherichia coli K12/metabolismo , Fatores de Transcrição/fisiologia
14.
Ophthalmic Res ; 66(1): 611-619, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36682350

RESUMO

BACKGROUND: Laser photocoagulation is an effective procedure for the treatment of diabetic macular edema (DME). However, the beneficial effects of conventional laser photocoagulation (CLP) are accompanied by the destruction of retinal photoreceptors. Therefore, subthreshold micropulse laser photocoagulation (SMLP) was proposed for DME. OBJECTIVES: This meta-analysis study was performed to evaluate the efficacy and safety of SMLP compared with CLP for the management of DME. METHODS: The PubMed, Embase, Web of Science, Cochrane, SinoMed, ClinicalTrials.gov, Wanfang, and China National Knowledge Infrastructure (CNKI) databases, published until Dec 2021, were searched to identify studies evaluating the clinical outcomes of SMLP for DME. RESULTS: Eight randomized controlled trials were selected for this meta-analysis involving a total of 546 eyes (275 eyes in SMLP group and 271 eyes in CLP group). SMLP of different wavelengths (577 nm and 810 nm) and duty cycles (5% and 15%) was applied. The pooled outcomes showed that SMLP group, especially 577 nm and 810 nm 15% duty cycle parameter settings, had a statistically significant higher efficacy than CLP group in terms of BCVA (MD = -0.02, 95% CI: -0.03 to -0.01, p < 0.01; MD = -0.09, 95% CI: -0.09 to -0.09, p < 0.01) and showed more significant advantages than CLP group in resolving macular edema assessed by reduction of CMT (MD = -32.87, 95% CI: -37.61 to -28.13, p < 0.01; MD = -8.01, 95% CI: -9.06 to -6.96, p < 0.01), whereas the efficacy of 577 nm and 810 nm 5% duty cycle SMLP subgroups remained numerically superior to CLP group, but nonsignificantly (p > 0.05). In the field of CS, SMLP group (no matter parameter settings) resulted in better preservation of CS compared to CLP group (MD = 1.96, 95% CI: 1.47-2.46, p < 0.01). CONCLUSIONS: Compared with CLP, SMLP may get superior efficacy and safety on improvement of BCVA, reduction of CMT, and preservation of CS. In clinical, SMLP can be considered as a safe and effective therapy in the management of DME.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Humanos , Fotocoagulação a Laser/métodos , Acuidade Visual , Lasers , Resultado do Tratamento
15.
Molecules ; 28(21)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37959818

RESUMO

The objective of the present study was to develop PTF-loaded solid lipid nanoparticles (PTF-SLNs) and investigate their efficacy in treating lung cancer. The PTF-SLNs were prepared by the thin film hydration method and verified by FTIR and TEM. Their physicochemical properties were characterized by particle size, polydispersity index (PDI), zeta potential, entrapment efficiency (EE), drug loading (DL), etc. Then, the pharmacodynamic studies of PTF-SLNs were performed on Lewis lung cancer cells and tumor-bearing mice. Finally, the safety studies were assessed by organ index, serum biochemical indicators, and histopathological changes. The PTF-SLNs were characterized by around 50 nm sphere nanoparticles, sustained ideal stability, and controlled drug release effects. The pharmacodynamic evaluation results showed that PTF-SLNs had stronger anti-tumor efficacy than PTF. An in vitro study revealed a more obvious cytotoxicity and apoptosis effect. The IC 50 values of PTF and PTF-SLNs were 67.43 µg/mL and 20.74 µg/mL, respectively. An in vivo study showed that the tumor inhibition rates of 2 g/kg PTF and 0.4 g/kg PTF-SLNs were 59.97% and 64.55%, respectively. The safety preliminary study indicated that PTF-SLNs improve the damage of PTF to normal organs to a certain extent. This study provides a nanoparticle delivery system with phenolic herbal extract to improve anti-tumor efficacy in lung cancer.


Assuntos
Neoplasias Pulmonares , Nanopartículas , Camundongos , Animais , Neoplasias Pulmonares/tratamento farmacológico , Lipídeos/química , Taninos , Lipossomos , Nanopartículas/química , Tamanho da Partícula , Portadores de Fármacos/química
16.
Biochem Biophys Res Commun ; 601: 86-92, 2022 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-35231656

RESUMO

RNA interference (RNAi)-based gene therapy that promotes anabolic bone formation is an effective approach for addressing osteoporosis. However, the selection of target gene and tissue-specific delivery systems has hindered the progression of this strategy. In this study, we identified casein kinase-2 interacting protein-1 encoding gene (Ckip-1), a negative regulator of bone formation, as an effective target of small interfering RNAs (siRNAs) for improving bone mass. Moreover, an impressive (DSS)6-Liposome (Lipos) nanoparticle system that could target the bone formation surface was synthesized to enhance the delivery of Ckip-1 siRNA to osteogenic lineage cells. The in vitro results confirmed that the (DSS)6-Lipos system could efficaciously improve the intracellular delivery of Ckip-1 siRNA without obvious cell toxicity. The in vivo application of the delivery system showed specific accumulation of siRNA in osteogenic cells located around the bone formation surface. Bone-related analysis indicated increased bone mass and improved bone microarchitecture in mice with ovariectomy-induced osteoporosis. Moreover, the biomechanical characteristics of the tibia were enhanced significantly, indicating increased resistance to fragile fracture induced by osteoporosis. Thus, (DSS)6-Lipos-Ckip-1 siRNA-based osteoanabolic therapy may be a promising option for the treatment of osteoporosis.


Assuntos
Osteogênese , Osteoporose , Animais , Proteínas de Transporte/metabolismo , Feminino , Lipossomos , Camundongos , Osteogênese/genética , Osteoporose/genética , Osteoporose/metabolismo , Osteoporose/terapia , Interferência de RNA , RNA Interferente Pequeno/genética , Terapêutica com RNAi
17.
PLoS Comput Biol ; 17(1): e1008596, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33465077

RESUMO

The fitness landscape is a concept commonly used to describe evolution towards optimal phenotypes. It can be reduced to mechanistic detail using genome-scale models (GEMs) from systems biology. We use recently developed GEMs of Metabolism and protein Expression (ME-models) to study the distribution of Escherichia coli phenotypes on the rate-yield plane. We found that the measured phenotypes distribute non-uniformly to form a highly stratified fitness landscape. Systems analysis of the ME-model simulations suggest that this stratification results from discrete ATP generation strategies. Accordingly, we define "aero-types", a phenotypic trait that characterizes how a balanced proteome can achieve a given growth rate by modulating 1) the relative utilization of oxidative phosphorylation, glycolysis, and fermentation pathways; and 2) the differential employment of electron-transport-chain enzymes. This global, quantitative, and mechanistic systems biology interpretation of fitness landscape formed upon proteome allocation offers a fundamental understanding of bacterial physiology and evolution dynamics.


Assuntos
Escherichia coli , Aptidão Genética/genética , Proteoma , Trifosfato de Adenosina/metabolismo , Escherichia coli/classificação , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Evolução Molecular , Regulação Bacteriana da Expressão Gênica/genética , Genoma Bacteriano/genética , Modelos Genéticos , Nitratos/metabolismo , Fenótipo , Proteoma/genética , Proteoma/metabolismo , Biologia de Sistemas
18.
Immunol Invest ; 51(3): 465-479, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33140671

RESUMO

BACKGROUND: Osteoporosis is a common metabolic bone disease with high prevalence. Tetrandrine (TET) suppressed osteoclastogenesis, while the roles of TET in osteoporosis regulation remained unclear. Thus, the study aimed to investigate the effect of TET on osteoporosis and the underlying mechanism. METHODS: The osteoporosis rabbit model was established through anterior cruciate ligament transection (ACLT) and bilateral ovariectomy (OVX). The degeneration of articular cartilage was assessed using HE staining and Alcian blue staining. The liver and kidney tissue injury was determined using HE staining. The activity of osteoclasts was evaluated using Tartrate-resistant acid phosphatase (TRAP) staining. The changes in bone structural parameters were determined through measuring the BMD, BV/TV, Tb.Th, Tb.N, and Tb.Sp, and the serum levels of calcium and phosphorus. Macrophage polarization was determined using Flow cytometry. RESULTS: The bone structural parameters including BMD, BV/TV, Tb.N, Tb.Th and Tb.Sp were changed in osteoporosis rabbit, which was reversed by TET. Besides, TET suppressed the increased serum levels of calcium and phosphorus in osteoporosis rabbit. Furthermore, TET inhibited the degeneration of articular cartilage and the activity of osteoclasts induced by osteoporosis. Moreover, TET inhibited the levels of MMP-9, PPAR-γ, RANKL, ß-CTX and TRACP-5b, and increased the levels of OPG, ALP and osteocalcin (OC) in osteoporosis. Additionally, TET promoted macrophage transformation from M1 to M2 in osteoporotic and inhibited the production of IL-1ß, TNF-α, and IL-6. TET also inhibited the p65 phosphorylation in osteoporosis. Besides, TET reversed RANKL-induced osteoclasts proliferation, p65 phosphorylation, and the expression changes of RANKL, Ki67, PPAR-γ, ALP, OPG. CONCLUSION: TET attenuated bone structural parameters including BMD, BV/TV, Tb.N, Tb.Th and Tb.Sp, inhibited articular cartilage degeneration, promoted bone formation, inhibited the inflammatory response, and promoted macrophage transformation from M1 to M2 via NF-κB inactivation in osteoporosis. TET may be a promising drug for osteoporosis therapy. ABBREVIATION: TET: Tetrandrine; ACLT: anterior cruciate ligament transection; OVX: ovariectomy; TRAP: Tartrate-resistant acid phosphatase; BMD: bone mineral density; BV/TV: Bone volume/total volume; Tb.Th: trabecular thickness; Tb.N: trabecular number; Tb.Sp: trabecular separation; MMP-9: Matrix metallopeptidase 9; PPAR-γ: Peroxisome proliferator-activated receptor gamma; RANKL: Receptor activator of nuclear factor kappa-B ligand; OPG: Osteoprotegerin; ALP: alkaline phosphatase; OC: osteocalcin; ß-CTX: ß isomer of C-terminal telopeptide of type I collagen; TRACP-5b: Tartrate-resistant acid phosphatase 5b; TNF-α: tumor necrosis factor-α; IL-1ß: interleukin-1ß; IL-6: interleukin 6; NF-κB: Nuclear factor kappa B; PKC-α: Protein kinase C alpha; qRT-PCR: Quantitative real-time polymerase chain reaction.


Assuntos
Osteoclastos , Osteoporose , Animais , Benzilisoquinolinas , Cartilagem/metabolismo , Cartilagem/patologia , Proliferação de Células , Feminino , Humanos , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Osteoporose/metabolismo , Ovariectomia , Fosforilação , Ligante RANK , Coelhos
19.
Neurourol Urodyn ; 41(1): 174-187, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34622458

RESUMO

AIMS: The therapeutic effect of estrogen on interstitial cystitis/bladder pain syndrome is unclear. We aim to explore the effect of estrogen on bladder overactivity in rats with cyclophosphamide-induced cystitis and its underlying mechanism. METHODS: In vivo cystometry was used to determine the effect of estrogen on bladder excitability. The effect of estrogen on the expression of P2X3 receptors in bladder epithelium was detected by real-time polymerase chain reaction and western blot. Effect of P2X3 receptors in bladder urothelium on stretch-released adenosine triphosphate was performed by a Flexcell FX5000 Compression system and an Enzyme-Linked Immunosorbent Assay Kit. RESULTS: Estrogen deprivation significantly increased the urinary frequency, while supplementation with diarylpropionitrile (DPN), an estrogen receptor ß (ERß) agonist, alleviated the urinary frequency. 17ß-Estradiol and DPN decreased the expression of P2X3 receptors in urothelium cells which was partially inhibited by ERß antagonist 4-[2-phenyl-5,7-bis(trifluoromethyl)pyrazolo[1,5-a]pyrimidin-3-yl]phenol. Meanwhile, inhibiting the expression of P2X3 receptors by ERß agonist or antagonizing the function of P2X3 receptors by selective P2X3 receptor antagonist AF-353 or A-317491 significantly reduced the stretch-released ATP from urothelium cells. CONCLUSIONS: Estrogen has a direct effect on the regulation of bladder overactivity in rats with cyclophosphamide-induced cystitis by downregulating the expression of bladder epithelial P2X3 receptors through ERß and reducing the adenosine triphosphate released from urothelium during bladder filling, thereby inhibiting the generation of the micturition reflex.


Assuntos
Cistite , Receptores Purinérgicos P2X3 , Bexiga Urinária , Trifosfato de Adenosina/metabolismo , Animais , Ciclofosfamida/farmacologia , Cistite/induzido quimicamente , Cistite/tratamento farmacológico , Cistite/metabolismo , Estrogênios/metabolismo , Estrogênios/farmacologia , Estrogênios/uso terapêutico , Ratos , Receptores Purinérgicos P2X3/metabolismo , Urotélio/metabolismo
20.
Nucleic Acids Res ; 48(18): 10157-10163, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32976587

RESUMO

A genome contains the information underlying an organism's form and function. Yet, we lack formal framework to represent and study this information. Here, we introduce the Bitome, a matrix composed of binary digits (bits) representing the genomic positions of genomic features. We form a Bitome for the genome of Escherichia coli K-12 MG1655. We find that: (i) genomic features are encoded unevenly, both spatially and categorically; (ii) coding and intergenic features are recapitulated at high resolution; (iii) adaptive mutations are skewed towards genomic positions with fewer features; and (iv) the Bitome enhances prediction of adaptively mutated and essential genes. The Bitome is a formal representation of a genome and may be used to study its fundamental organizational properties.


Assuntos
Escherichia coli K12/genética , Genoma Bacteriano , Genômica
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