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1.
Hereditas ; 158(1): 32, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34425910

RESUMO

BACKGROUND: Coarctation of the aorta (CoA) is a serious innate heart disease. Although surgery results are generally good, some complications such as recoarctation and aortic aneurysm or persistent hypertension were serious threats to patient's health. To better understand the pathology of CoA and its underlying molecular mechanism is particularly important for early diagnosis and preventing the occurrence of its complications. However, the mechanisms of CoA remain unclear, especially for infants. METHODS: RNA sequencing (RNA-seq) was used to identify the differentially expressed genes (DEGs) in vascular tissues of 12 patients with CoA and 10 normal participants form 3- to 34-month-old infants. The characteristic of DEGs were validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunochemical staining (IHC) in vessels of patients with CoA and normal infants. RESULTS: A total of 2491 DEGs with the false discovery rate less than 0.05(> 1.5-fold, P < 0.05 change) were identified, including 443 upregulated genes and 2048 downregulated genes. The Gene Ontology enrichment analysis showed that 26 out of the 2491 DEGs identified were associated with cardiovascular diseases. These 26 genes were mainly associated with extracellular matrix (ECM) and smooth muscle cells (SMCs) differentiation. Three DEGs, that is, CNN1 (calponin), α-actinin1 and myosin heavy chain 11 MYH11, were validated using qRT-PCR and Western blot analysis. In addition, immunochemical staining showed that calponin and MYH11 were highly expressed on the surface and in the deep layers of the thickened intima respectively. CONCLUSION: This study comprehensively characterized the CoA transcriptome. Migration of extracellular matrix (ECM) and smooth muscle cells (SMCs) to the subendothelial space may be the major characteristic of CoA in infants.


Assuntos
Coartação Aórtica/genética , Análise de Sequência de RNA , Transcriptoma , Actinina/genética , Pequim , Proteínas de Ligação ao Cálcio/genética , Estudos de Casos e Controles , Feminino , Ontologia Genética , Humanos , Lactente , Masculino , Proteínas dos Microfilamentos/genética , Cadeias Pesadas de Miosina/genética , Calponinas
2.
Nucleic Acids Res ; 46(15): 7953-7969, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-29796672

RESUMO

Adenosine-to-inosine (A-to-I) RNA editing entails the enzymatic deamination of adenosines to inosines by adenosine deaminases acting on RNA (ADARs). Dysregulated A-to-I editing has been implicated in various diseases, including cancers. However, the precise factors governing the A-to-I editing and their physiopathological implications remain as a long-standing question. Herein, we unravel that DEAH box helicase 9 (DHX9), at least partially dependent of its helicase activity, functions as a bidirectional regulator of A-to-I editing in cancer cells. Intriguingly, the ADAR substrate specificity determines the opposing effects of DHX9 on editing as DHX9 silencing preferentially represses editing of ADAR1-specific substrates, whereas augments ADAR2-specific substrate editing. Analysis of 11 cancer types from The Cancer Genome Atlas (TCGA) reveals a striking overexpression of DHX9 in tumors. Further, tumorigenicity studies demonstrate a helicase-dependent oncogenic role of DHX9 in cancer development. In sum, DHX9 constitutes a bidirectional regulatory mode in A-to-I editing, which is in part responsible for the dysregulated editome profile in cancer.


Assuntos
Adenosina/metabolismo , RNA Helicases DEAD-box/metabolismo , Inosina/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Edição de RNA , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Animais , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , RNA Helicases DEAD-box/genética , Desaminação , Doxorrubicina/farmacologia , Células HEK293 , Humanos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Proteínas de Neoplasias/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Interferência de RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
3.
Soft Matter ; 15(34): 6836-6841, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31402364

RESUMO

An azine-containing bispillar[5]arene was designed and synthesized by the reaction of aldehyde functionalized-pillar[5]arene and hydrazine. Then, a novel bispillar[5]arene-based supramolecular pseudopolyrotaxane has been successfully prepared via host-guest interaction. Interestingly, by taking advantage of the host-guest interactions, π-π stacking interactions and hydrogen bonding interactions, the multi-stimuli-responsive gel-sol phase transitions of such a supramolecular pseudopolyrotaxane gel were successfully realized under different stimuli, such as acid, temperature, concentration, and competitive guests. Moreover, this supramolecular system could effectively adsorb dye molecule rhodamine B. It is worth noting that this supramolecular pseudopolyrotaxane gel prepared in cyclohexanol solution (BP5·G·C) could be used as an adsorbent material for adsorbing rhodamine B with adsorption efficiency of 98.4%. Meanwhile, the adsorption efficiency was 97.6% for supramolecular pseudopolyrotaxane gel prepared in DMSO-H2O (v : v, 8 : 2) binary solution (BP5·G·D), also indicating the superior adsorption effect of BP5·G·D toward the dye molecule rhodamine B.

4.
Nucleic Acids Res ; 45(18): 10436-10451, 2017 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-28985428

RESUMO

Adenosine-to-inosine (A-to-I) RNA editing, catalyzed by Adenosine DeAminases acting on double-stranded RNA(dsRNA) (ADAR), occurs predominantly in the 3' untranslated regions (3'UTRs) of spliced mRNA. Here we uncover an unanticipated link between ADARs (ADAR1 and ADAR2) and the expression of target genes undergoing extensive 3'UTR editing. Using METTL7A (Methyltransferase Like 7A), a novel tumor suppressor gene with multiple editing sites at its 3'UTR, we demonstrate that its expression could be repressed by ADARs beyond their RNA editing and double-stranded RNA (dsRNA) binding functions. ADARs interact with Dicer to augment the processing of pre-miR-27a to mature miR-27a. Consequently, mature miR-27a targets the METTL7A 3'UTR to repress its expression level. In sum, our study unveils that the extensive 3'UTR editing of METTL7A is merely a footprint of ADAR binding, and there are a subset of target genes that are equivalently regulated by ADAR1 and ADAR2 through their non-canonical RNA editing and dsRNA binding-independent functions, albeit maybe less common. The functional significance of ADARs is much more diverse than previously appreciated and this gene regulatory function of ADARs is most likely to be of high biological importance beyond the best-studied editing function. This non-editing side of ADARs opens another door to target cancer.


Assuntos
Adenosina Desaminase/metabolismo , Redes Reguladoras de Genes/fisiologia , Neoplasias/genética , Edição de RNA , RNA de Cadeia Dupla/metabolismo , Proteínas de Ligação a RNA/metabolismo , Regiões 3' não Traduzidas/genética , Adenosina/metabolismo , Animais , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Inosina/metabolismo , Neoplasias/metabolismo , Células Tumorais Cultivadas
5.
Gastroenterology ; 151(4): 637-650.e10, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27373511

RESUMO

BACKGROUD & AIMS: Gastric cancer (GC) is the third leading cause of global cancer mortality. Adenosine-to-inosine RNA editing is a recently described novel epigenetic mechanism involving sequence alterations at the RNA but not DNA level, primarily mediated by ADAR (adenosine deaminase that act on RNA) enzymes. Emerging evidence suggests a role for RNA editing and ADARs in cancer, however, the relationship between RNA editing and GC development and progression remains unknown. METHODS: In this study, we leveraged on the next-generation sequencing transcriptomics to demarcate the GC RNA editing landscape and the role of ADARs in this deadly malignancy. RESULTS: Relative to normal gastric tissues, almost all GCs displayed a clear RNA misediting phenotype with ADAR1/2 dysregulation arising from the genomic gain and loss of the ADAR1 and ADAR2 gene in primary GCs, respectively. Clinically, patients with GCs exhibiting ADAR1/2 imbalance demonstrated extremely poor prognoses in multiple independent cohorts. Functionally, we demonstrate in vitro and in vivo that ADAR-mediated RNA misediting is closely associated with GC pathogenesis, with ADAR1 and ADAR2 playing reciprocal oncogenic and tumor suppressive roles through their catalytic deaminase domains, respectively. Using an exemplary target gene PODXL (podocalyxin-like), we demonstrate that the ADAR2-regulated recoding editing at codon 241 (His to Arg) confers a loss-of-function phenotype that neutralizes the tumorigenic ability of the unedited PODXL. CONCLUSIONS: Our study highlights a major role for RNA editing in GC disease and progression, an observation potentially missed by previous next-generation sequencing analyses of GC focused on DNA alterations alone. Our findings also suggest new GC therapeutic opportunities through ADAR1 enzymatic inhibition or the potential restoration of ADAR2 activity.


Assuntos
Adenosina Desaminase/genética , Edição de RNA , Proteínas de Ligação a RNA/genética , Neoplasias Gástricas/genética , Códon , Progressão da Doença , Epigênese Genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sequência de RNA , Sialoglicoproteínas/genética , Neoplasias Gástricas/patologia , Transcriptoma
6.
Curr Microbiol ; 71(4): 458-64, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26178900

RESUMO

Trioxacarcin A is a polyoxygenated, structurally complex antibiotic produced by Streptomyces spp., which possesses high anti-bacterial, anti-malaria, and anti-tumor activities. The trioxacarcin biosynthetic pathway involves type II polyketide synthases (PKSs) with L-isoleucine as a unique starter unit, as well as many complex post-PKS tailoring enzymes and resistance and regulatory proteins. In this work, two regulatory genes, txn9 coding for a Streptomyces antibiotic regulatory protein family regulator and txn11 for a two-component response regulator, were revealed to be absolutely required for trioxacarcin production by individually inactivating all the six annotated regulatory genes in the txn cluster. Complementation assay suggested that these two activators do not have a regulatory cascade relationship. Moreover, transcriptional analysis showed that they activate 15 of the 28 txn operons, indicating that a complicated regulatory network is involved in the trioxacarcin production. Information gained from this study may be useful for improving the production of the highly potent trioxacarcin A.


Assuntos
Aminoglicosídeos/biossíntese , Anti-Infecciosos/metabolismo , Antineoplásicos/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Streptomyces/genética , Transativadores/metabolismo , Deleção de Genes , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Teste de Complementação Genética , Família Multigênica , Streptomyces/metabolismo
7.
Gut ; 63(5): 832-43, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23766440

RESUMO

OBJECTIVE: Hepatocellular carcinoma (HCC) is a heterogeneous tumour displaying a complex variety of genetic and epigenetic changes. In human cancers, aberrant post-transcriptional modifications, such as alternative splicing and RNA editing, may lead to tumour specific transcriptome diversity. DESIGN: By utilising large scale transcriptome sequencing of three paired HCC clinical specimens and their adjacent non-tumour (NT) tissue counterparts at depth, we discovered an average of 20 007 inferred A to I (adenosine to inosine) RNA editing events in transcripts. The roles of the double stranded RNA specific ADAR (Adenosine DeAminase that act on RNA) family members (ADARs) and the altered gene specific editing patterns were investigated in clinical specimens, cell models and mice. RESULTS: HCC displays a severely disrupted A to I RNA editing balance. ADAR1 and ADAR2 manipulate the A to I imbalance of HCC via their differential expression in HCC compared with NT liver tissues. Patients with ADAR1 overexpression and ADAR2 downregulation in tumours demonstrated an increased risk of liver cirrhosis and postoperative recurrence and had poor prognoses. Due to the differentially expressed ADAR1 and ADAR2 in tumours, the altered gene specific editing activities, which was reflected by the hyper-editing of FLNB (filamin B, ß) and the hypo-editing of COPA (coatomer protein complex, subunit α), are closely associated with HCC pathogenesis. In vitro and in vivo functional assays prove that ADAR1 functions as an oncogene while ADAR2 has tumour suppressive ability in HCC. CONCLUSIONS: These findings highlight the fact that the differentially expressed ADARs in tumours, which are responsible for an A to I editing imbalance, has great prognostic value and diagnostic potential for HCC.


Assuntos
Adenosina Desaminase/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Edição de RNA , RNA de Cadeia Dupla/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/cirurgia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Seguimentos , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/cirurgia , Masculino , Camundongos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Proteínas de Ligação a RNA/metabolismo , Resultado do Tratamento , Regulação para Cima
8.
Sci Total Environ ; 944: 173838, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38879025

RESUMO

The excessive accumulation of dibutyl phthalate (DBP) in soil poses a serious threat to soil ecosystems and crop safety production. Electrokinetic-assisted phytoremediation (EKPR) has been considered as a potential technology for remediating organic contaminated soils. In order to investigate the effect of different electric fields on removal efficiency of DBP, three kinds of electric fields were set up in this study (1 V·cm-1, 2 V·cm-1 and 3 V·cm-1). The results showed that 59 % of DBP in soil was removed by maize (Zea mays L.) within 20 d in low-intensity electric field (1 V·cm-1), and the accumulation of DBP in maize tissues decreased significantly compared to the non-electrified treatment group. Interestingly, it could be observed that the low-intensity electric field could maintain ion homeostasis and improve the photosynthetic efficiency of the plant, thereby relieving the inhibition of DBP on plant growth and increasing the chlorophyll content (94.1 %) of maize. However, the removal efficiency of DBP by maize decreased significantly under the medium-intensity (2 V·cm-1) and high-intensity electric field (3 V·cm-1). Moreover, the important roles of soil enzyme and rhizosphere bacterial community in low-electric field were also investigated and discussed. This study provided a new perspective for exploring the mechanism of removing DBP through EKPR.


Assuntos
Biodegradação Ambiental , Dibutilftalato , Poluentes do Solo , Zea mays , Zea mays/metabolismo , Poluentes do Solo/metabolismo , Dibutilftalato/metabolismo , Solo/química
9.
Cell Prolif ; : e13717, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39021353

RESUMO

Aerobic glycolysis is involved in the pathogenesis of pulmonary hypertension (PH). The mechanisms by which glycolysis is increased and how it contributes to pulmonary vascular remodelling are not yet fully understood. In this study, we demonstrated that elevated lipocalin-2 (LCN2) in PH significantly enhances aerobic glycolysis in human pulmonary artery smooth muscle cells (PASMCs) by up-regulating LDHA expression. Knockout of Lcn2 or having heterozygous LDHA deficiency in mice significantly inhibits the progression of hypoxic PH. Our study reveals that LCN2 stimulates LDHA expression by activating Akt-HIF-1α signalling pathway. Inhibition of Akt or HIF-1α reduces LDHA expression and proliferation of PASMCs. Both Akt and HIF-1α play critical roles in the development of PH and are suppressed in the pulmonary vessels of hypoxic PH mice lacking LCN2. These findings shed light on the LCN2-Akt-HIF1α-LDHA axis in aerobic glycolysis in PH.

10.
Int J Cancer ; 133(6): 1368-79, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23483548

RESUMO

Kindlin 2, as a focal adhesion protein, controls integrin activation and regulates Wnt signaling in an integrin-binding independent manner. However, the association of Kindlin 2 with cancer-related microRNAs is unknown. Here, we report that Kindlin 2 markedly downregulates the expression of miR-200 family by inducing CpG island hypermethylation. Mechanistically, Kindlin 2 forms a complex with DNMT3A in the cell nucleus and the two proteins co-occupy the promoter of miRNA-200b. Functionally, repression of miR-200b is required for Kindlin 2-induced breast cancer cell invasion and tumor formation. Our data indicate that Kindlin 2 plays a novel role in epigenetic repression of miR-200 family, a mechanism that promotes breast cancer invasion.


Assuntos
Neoplasias da Mama/patologia , Inativação Gênica , Proteínas de Membrana/fisiologia , MicroRNAs/genética , Proteínas de Neoplasias/fisiologia , Animais , Linhagem Celular Tumoral , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferases/fisiologia , Metilação de DNA , DNA Metiltransferase 3A , Feminino , Humanos , Camundongos , Camundongos SCID , Invasividade Neoplásica
11.
Infect Med (Beijing) ; 2(4): 343-348, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38205174

RESUMO

Here we describe the first case of abscess infection caused by Nocardia beijingensis in China. The patient was immunocompetent but suffered from postoperative abscess for 6 years. This study highlights the necessity of long-term infected foci to be thoroughly examined to identify the pathogen, as well as the importance of accurate Nocardia identification and antimicrobial susceptibility tests for understanding the pathogen's epidemiology, clinical significance, and treatment strategy.

12.
Materials (Basel) ; 16(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38138774

RESUMO

The microstructure evolution and variation of impact toughness in the heat-affected zone (HAZ) of X80 pipeline steel with different Nb content under different peak temperatures in the secondary thermal cycle were studied through welding thermal simulation, the Charpy impact test, EBSD analysis, SEM observation, and TEM observation in this study. The results indicate that when the peak temperatures of the second pass were lower than Ac1, both X80 pipeline steels had high impact toughness. For secondary peak temperatures in the range of Ac1 to Ac3, both X80 pipeline steels had the worst impact toughness, mainly due to the formation of massive blocky M-A constituents in chain form on grain boundaries. When the secondary peak temperatures were higher than Ac3, both X80 pipeline steels had excellent impact toughness. Smaller grain size and higher proportions of HAGBs can effectively improve the impact toughness. Meanwhile, high Nb X80 pipeline steel had higher impact absorption energy and smaller dispersion. Adding an appropriate amount of Nb to X80 pipeline steel can ensure the impact toughness of SCCGHAZ and SCGHAZ in welded joints.

13.
Microbiol Spectr ; 10(5): e0169022, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36190403

RESUMO

Bloodstream infection (BSI) caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) is a serious and urgent threat for hospitalized patients. This study aims to describe the clinical and molecular characteristics of CRKP causing BSI in a tertiary-care hospital in Beijing, China. A total of 146 CRKP strains and 39 carbapenem-susceptible K. pneumoniae (CSKP) strains collected in the hospital from 2017 to 2020 were sent for whole-genome sequencing. Univariate and multivariate analyses were used to evaluate risk factors for in-hospital mortality of CRKP-BSI cases. Thirty (20.5%) of 146 CRKP-BSI patients and three (7.7%) of 39 CSKP-BSI patients died at discharge (χ2 = 3.471, P = 0.062). Multivariate logistic regression analysis indicated that age and use of urinary catheters were independent risk factors for the death of CRKP-BSI. The 146 CRKP isolates belonged to 9 sequence types (STs) and 11 serotypes, while the 39 CSKP isolates belonged to 23 STs and 27 serotypes. The mechanism of carbapenem resistance for all the CRKP strains was the acquisition of carbapenemase, mainly KPC-2 (n = 127). There were 2 predominant serotypes for ST11 CRKP, namely, KL47 (n = 82) and KL64 (n = 42). Some virulent genes, including rmpA2, iucABCD and iutA, and repB gene, which was involved in plasmid replication, were detected in all ST11-KL64 strains. Evolutionary transmission analysis suggested that ST11 CRKP strains might have evolved from KL47 into KL64 and were accompanied by multiple outbreak events. This study poses an urgent need for enhancing infection control measures in the hospital, especially in the intensive care unit where the patients are at high-risk for acquiring CRKP-BSI. IMPORTANCE CRKP-BSI is demonstrated to cause high mortality. In this study, we demonstrated that ST11 CRKP strains might carry many virulent genes. Meanwhile, outbreak events occurred several times in the strains collected. Carbapenemase acquisition (mainly KPC-2 carbapenemase) was responsible for carbapenem resistance of all the 146 CRKP strains. As 2 predominant strains, all ST11-KL64 strains, but not ST11-KL47 strains, carried rmpA2, iucABCD, iutA, as well as a plasmid replication initiator (repB). Our study suggested that the occurrence of region-specific recombination events manifested by the acquisition of some virulence genes might contribute to serotype switching from ST11-KL47 to ST11-KL64. The accumulation of virulent genes in epidemic resistant strains poses a great challenge for the prevention and treatment of BSI caused by K. pneumoniae in high-risk patients.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Klebsiella , Sepse , Humanos , Klebsiella pneumoniae/genética , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Hospitais , Sepse/tratamento farmacológico
14.
Front Microbiol ; 13: 1086296, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36687642

RESUMO

Klebsiella michiganensis is an increasingly important bacterial pathogen causing nosocomial infections in clinical patients. In this study, we described the molecular and genomic characteristics of a carbapenem-resistant K. michiganensis strain KM166 cultured from a one-month premature baby's blood sample. KM166 showed lower biofilm forming ability in optical density (OD) than K. pneumoniae NTUH-K2044 (0.271 ± 0.027 vs. 0.595 ± 0.054, p = 0.001), and the median lethal dose (0.684 lg CFU/mL) was lower than K. pneumoniae strain NTUH-K2044 (6.679 lg CFU/mL). A IncFII/IncFIA(HI1)/IncFIB(K) multiple replicon plasmid in KM166 was identified carrying three replicon types. It has low homology to Escherichia coli pMRY09-581ECO_1 and the highest homology similarity to the INcFIA/INcFII(p14)-type plasmid in K. michiganensis strain fxq plasmid pB_KPC, suggesting that this multiple replicon plasmid was unlikely to have been transmitted from E. coli and probably a transfer of repFIB replicon genes from other K. michiganensis strains into the INcFIA/INcFII(p14)-type plasmid of KM166 had occurred. Mapping of the gene environment revealed that bla KPC-2 in KM166 plasmid 3 had high identity and same Tn3-tnpR-IS481-bla KPC-2-klcA_1 genomic context structure with K. pneumoniae strain JKP55, plasmid pKPC-J5501, and bla KPC-2-carrying plasmid proved to be autonomously transferred under the help of mobile genetic elements into Escherichia coli 600 by plasmid conjugation experiment. In conclusion, we have characterized a K. michiganensis strain carrying multi-replicon IncFII/IncFIA(HI1)/IncFIB(K) plasmid and bla KPC-2-carrying IncFII(p14)/IncFIA plasmid in this study, which provided insights about the evolutionary diversity of plasmids carried by K. michiganensis.

15.
J Orthop Translat ; 31: 1-9, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34692412

RESUMO

BACKGROUND/OBJECTIVE: Coronavirus disease 2019 (COVID-19) is a disaster in human medical history and glucocorticoids remain the most promising therapy. Osteonecrosis is a disease caused by reduced intraosseous blood flow to bones in the joints, which will rapidly induce joint destruction. Approximately one-third patients with severe acute respiratory syndrome (SARS) who received high cumulative doses and long treatment durations of glucocorticoids occurred osteonecrosis. Considering the similarity of SARS and COVID-19 on their pathogen, clinical characteristics, and therapeutic strategies, it is particularly desirable to investigate whether osteonecrosis will become a common sequela among convalescent COVID-19 patients. METHODS: This multi-strategy study was designed by integrating different research methods, such as meta-analysis, systematic review, and cross-sectional investigations to address above study objectives. At first, two meta-analyses were performed on the osteonecrosis incidence among SARS patients and the clinical data of glucocorticoid exposure among COVID-19 patients. Then, a systematic review of low-dosage glucocorticoid associated osteonecrosis and a cross-sectional investigation of glucocorticoid exposure of COVID-19 patients in Wuhan city of China were also conducted. Moreover, the pathogenesis, diagnosis, prevention, and treatment options for osteonecrosis patients with COVID-19 infection were further presented and discussed. RESULTS: Our meta-analysis showed that 32% of SARS patients had developed osteonecrosis after receiving glucocorticoid treatment with high dose, and our system review supported that low level glucocorticoid exposure might also lead to the occurrence of osteonecrosis. Similarly, 40% of COVID-19 patients had undergone glucocorticoid treatment according to our meta-analysis. The cross-sectional investigation in Wuhan city of China found that the average of cumulative glucocorticoid exposure level was 504 â€‹mg calculated by the dosage of methylprednisolone. Notably, a confirmed osteonecrosis case was identified from 1406 patients with COVID-19 during our cross-sectional investigation, implying that preventive management of osteonecrosis should be better started with regular clinical follow-up observation. CONCLUSION: Growing evidence of the glucocorticoid therapy for COVID-19 patients prompts us to establish risk-classification-based early screening and to introduce early prevention protocol of its associated osteonecrosis that will be of clinical significance in favor of improved prognosis of this disease. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: To establish risk-classification-based early screening and to introduce early prevention protocol of glucocorticoid-induced osteonecrosis will be of clinical significance in favor of improved prognosis of COVID-19.

16.
Cancer Res ; 80(13): 2737-2750, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32312833

RESUMO

Aberrant activation of histone methyltransferase EZH2 and ribosome synthesis strongly associate with cancer development and progression. We previously found that EZH2 regulates RNA polymerase III-transcribed 5S ribosomal RNA gene transcription. However, whether EZH2 regulates ribosome synthesis is still unknown. Here, we report that EZH2 promotes ribosome synthesis by targeting and silencing a long noncoding RNA PHACTR2-AS1. PHACTR2-AS1 directly bound ribosome DNA genes and recruited histone methyltransferase SUV39H1, which in turn triggered H3K9 methylation of these genes. Depletion of PHACTR2-AS1 resulted in hyperactivation of ribosome synthesis and instability of ribosomal DNA, which promoted cancer cell proliferation and metastasis. Administration of PHACTR2-AS1-30nt-RNA, which binds to SUV39H1, effectively inhibited breast cancer growth and lung metastasis in mice. PHACTR2-AS1 was downregulated in breast cancer patients, where lower PHACTR2-AS1 expression promoted breast cancer development and correlated with poor patient outcome. Taken together, we demonstrate that PHACTR2-AS1 maintains a H3K9 methylation-marked silent state of ribosomal DNA genes, comprising a regulatory axis that controls breast cancer growth and metastasis. SIGNIFICANCE: These findings reveal that EZH2 mediates ribosomal DNA stability via silencing of PHACTR2-AS1, representing a potential therapeutic target to control breast cancer growth and metastasis.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Instabilidade Genômica , Neoplasias Pulmonares/secundário , RNA Longo não Codificante/genética , Ribossomos/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proliferação de Células , Progressão da Doença , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas dos Microfilamentos/antagonistas & inibidores , Proteínas do Tecido Nervoso/antagonistas & inibidores , Prognóstico , RNA Antissenso/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Cell Death Dis ; 10(12): 890, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31767831

RESUMO

Kindlin-2 plays an important role in the regulation of cardiac structure and function. Depletion of Kindlin-2 contributes to cardiac hypertrophy and progressive heart failure, however, the precise mechanisms involved in this process remain unclear. GATA4 is a critical transcription factor in regulating cardiogenesis. We found that Kindlin-2 suppresses the expression of GATA4 through binding to its promoter and prevents cardiomyocytes from hypertrophy induced by isoproterenol (ISO) treatment. Mechanistically, Kindlin-2 interacts with histone methyltransferase SUV39H1 and recruits it to GATA4 promoter leading to the occupancy of histone H3K9 di- and tri-methylation. Furthermore, to confirm the function of Kindlin-2 in vivo, we generated mice with targeted deletion of cardiac Kindlin-2. We found that 6-month-old Kindlin-2 cKO mice have developed hypertrophic cardiomyopathy and that this pathological process can be accelerated by ISO-treatment. GATA4 expression was markedly activated in cardiac tissues of Kindlin-2 cKO mice compared to wild-type animals. Collectively, our data revealed that Kindlin-2 suppresses GATA4 expression by triggering histone H3K9 methylation in part and protects heart from pathological hypertrophy.


Assuntos
Cardiomegalia/metabolismo , Proteínas do Citoesqueleto/metabolismo , Fator de Transcrição GATA4/metabolismo , Metiltransferases/metabolismo , Proteínas Musculares/metabolismo , Proteínas Repressoras/metabolismo , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Ontologia Genética , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ligação Proteica , Ratos Sprague-Dawley
18.
Int J Biochem Cell Biol ; 105: 41-51, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30287284

RESUMO

Integrin-interacting protein Kindlin-2, as a focal adhesion protein, promotes growth and progression of breast cancer. However, the precise mechanism that underlie the role of Kindlin-2 in breast cancer is elusive. Here, we report that the expression of Kindlin-2 positively correlated with DNA methyltransferase 1(DNMT1) in breast cancer patients. Further, we found that DNMT1 was upregulated in mammary gland tissues of mammary specific Kindlin-2 transgenic mice. More importantly, high expression of DNMT1 was observed in mammary tumors formed by Kindlin-2 transgenic mice. On the basis of these observations, DNMT inhibitor 5-aza-CdR was used and found its treatment strongly decreased Kindlin-2-induced breast cancer cell proliferation and migration. Mechanistically, Kindlin-2 increased the stability of DNA methyltransferase DNMT1 through interaction with DNMT1 and methylated CpG islands in the E-cadherin promoter. Kindlin-2 increased the occupancy of DNMT1 at E-cadherin promoter, thereby suppressing E-cadherin expression. Taken together, our data reveal that Kindlin-2 promotes breast cancer development by enhancing the stability of DNMT1.


Assuntos
Neoplasias da Mama/etiologia , Neoplasias da Mama/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Animais , Antígenos CD/genética , Neoplasias da Mama/patologia , Caderinas/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ilhas de CpG , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferase 1/genética , Metilação de DNA , Estabilidade Enzimática , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Neoplasias Mamárias Experimentais/etiologia , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Proteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Proteínas de Neoplasias/genética , Regiões Promotoras Genéticas , Regulação para Cima
19.
J Infect ; 77(6): 561-571, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30219662

RESUMO

We describe the microbiological characterization and clinical presentation of two fungemia cases caused by fluconazole-resistant Candida auris in neonatal intensive care unit of a hospital in Beijing, China. We advocate for the need of guidelines or recommendations to improve identification, surveillance, and implementation of infection control measures in Chinese hospitals.


Assuntos
Candida/efeitos dos fármacos , Candidíase/tratamento farmacológico , Farmacorresistência Fúngica , Fluconazol/farmacologia , Fungemia/tratamento farmacológico , Antifúngicos/uso terapêutico , Candida/isolamento & purificação , Candidíase/microbiologia , China , Fungemia/microbiologia , Humanos , Lactente , Controle de Infecções , Terapia Intensiva Neonatal , Itraconazol/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Técnicas de Tipagem Micológica , Resultado do Tratamento
20.
Ultrasonics ; 81: 73-80, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28595165

RESUMO

Based on the modified Biot theory of Johnson, the propagation characteristics of the various interface waves at an interface between a semi-infinite fluid and a porous medium were studied. First, based on the characteristic equations of open-pore and sealed-pore, which were derived from the wave equations, time-domain waveforms at the interface were obtained by inverse Fourier transform. The effects of the longitudinal frame modulus on the interface waves were investigated. For open-pore and sealed-pore, the effect of porosity on the propagation of the interface waves was studied; the porosity was found to strongly influence the true surface wave. Based on four ultrasonic suspension models-Utrick, Utrick-Ament (UA), Harker-Temple (HT) and McClement, the pseudo-Stoneley wave propagation characteristics were analyzed at the interface between the sediment-containing two-phase fluid and the porous medium solid. The effects of volume fraction and particle diameter on the phase velocity, attenuation coefficient and dispersion for the pseudo-Stoneley and true surface wave were discussed, and the results demonstrated that the properties of the fluid strongly impacted the pseudo-Stoneley wave but exerted very little effect on the true surface wave. The conclusions drawn in this paper could contribute to elucidate the parameters of sediment and porous media.

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