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1.
Microb Pathog ; 188: 106560, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272327

RESUMO

Inflammatory bowel disease (IBD) is a chronic, recurrent inflammatory disease caused by the destruction of the intestinal mucosal epithelium that affects a growing number of people worldwide. Although the etiology of IBD is complex and still elucidated, the role of dysbiosis and dysregulated proteolysis is well recognized. Various studies observed altered composition and diversity of gut microbiota, as well as increased proteolytic activity (PA) in serum, plasma, colonic mucosa, and fecal supernatant of IBD compared to healthy individuals. The imbalance of intestinal microecology and intestinal protein hydrolysis were gradually considered to be closely related to IBD. Notably, the pivotal role of intestinal microbiota in maintaining proteolytic balance received increasing attention. In summary, we have speculated a mesmerizing story, regarding the hidden role of PA and microbiota-derived PA hidden in IBD. Most importantly, we provided the diagnosis and therapeutic targets for IBD as well as the formulation of new treatment strategies for other digestive diseases and protease-related diseases.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Humanos , Proteólise , Doenças Inflamatórias Intestinais/terapia , Intestinos , Mucosa Intestinal , Disbiose
2.
BMC Cancer ; 24(1): 611, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773399

RESUMO

RNA interactomes and their diversified functionalities have recently benefited from critical methodological advances leading to a paradigm shift from a conventional conception on the regulatory roles of RNA in pathogenesis. However, the dynamic RNA interactomes in adenoma-carcinoma sequence of human CRC remain unexplored. The coexistence of adenoma, cancer, and normal tissues in colorectal cancer (CRC) patients provides an appropriate model to address this issue. Here, we adopted an RNA in situ conformation sequencing technology for mapping RNA-RNA interactions in CRC patients. We observed large-scale paired RNA counts and identified some unique RNA complexes including multiple partners RNAs, single partner RNAs, non-overlapping single partner RNAs. We focused on the antisense RNA OIP5-AS1 and found that OIP5-AS1 could sponge different miRNA to regulate the production of metabolites including pyruvate, alanine and lactic acid. Our findings provide novel perspectives in CRC pathogenesis and suggest metabolic reprogramming of pyruvate for the early diagnosis and treatment of CRC.


Assuntos
Adenoma , Neoplasias Colorretais , MicroRNAs , Ácido Pirúvico , RNA Longo não Codificante , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Adenoma/genética , Adenoma/metabolismo , Adenoma/patologia , Ácido Pirúvico/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação Neoplásica da Expressão Gênica , Reprogramação Metabólica
3.
Opt Express ; 31(20): 32383-32392, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859043

RESUMO

Traditional pulse-amplitude-modulated discrete multitone modulation (PAM-DMT) suffers from poor overall performance of spectral and power efficiencies in optical wireless communication (OWC) systems. We propose layered hybrid PAM-DMT (LHPAM-DMT) to utilize more subcarriers to improve the performance. The real part of frequency domain signal is divided into several layers and symmetry biases are added in time domain to generate real-valued and nonnegative signals for intensity modulation with direct detection (IM/DD) OWC systems. By appropriately designing the orthogonality between the signals in lower layers and signals & added biases in higher layers, we further propose an iterative receiver to recover the transmitted information. Theoretical derivation proves that LHPAM-DMT has higher spectral efficiency than PAM-DMT and lower complexity than layered PAM-DMT. Numerical results suggest that LHPAM-DMT is more power efficient than PAM-DMT as well as direct-current (DC) biased optical OFDM (DCO-OFDM), one of the most popular schemes.

4.
Chem Biodivers ; 20(10): e202300620, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37690995

RESUMO

Five psoralen derivatives were synthesized and the structures of them were characterized by 1 H-NMR, 13 C-NMR, and IR. The antioxidant properties of the compounds were tested by inhibiting the free radical-initiated DNA oxidation and scavenging the radical reaction. The results showed that the effective stoichiometric factors (n) of the compounds V and IV could reach 2.00 and 2.11 in the system of inhibiting the DNA oxidation reaction initiated by 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH). In the inhibition of ⋅OH-oxidation of the DNA system, compounds I~V showed antioxidant properties. The thiobarbituric acid absorbance (TBARS) percentages of compounds IV and V were 76.19 % and 78.84 %. Compounds I~V could also inhibit Cu2+ /GSH-oxidation of DNA, and all compounds exhibited good antioxidant properties except compound II (94.00 %). All the five compounds were able to trap diammonium 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) salt radical (ABTS+ ⋅), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH⋅) and 2,6-di-tert-butyl-alpha-(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadien-p-tolylox radical (galvinoxyl⋅). The ability of compounds I~V to scavenge those free radicals can be measured by the k values. The k values ranged from 0.07 to 0.82 in scavenging ABTS+ ⋅, galvinoxyl, and DPPH radicals, respectively.

5.
Plant Dis ; 107(10): 3057-3063, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36916837

RESUMO

Root-knot nematodes (RKNs) are highly specialized parasites that cause significant yield losses worldwide. In this study, we isolated Bacillus pumilus strain S1-10 from the rhizosphere soil of Zingiber officinale Rosc. plants and evaluated its fumigant activity against Meloidogyne incognita. S1-10 exhibited a strong repellent effect on second-stage juveniles (J2s) of M. incognita, and in vitro assays indicated that S1-10 volatile organic compounds (VOCs) suppressed J2 activity and egg hatching. Under greenhouse conditions, 71 and 79% reductions of nematodes and eggs were detected on plants treated with S-10 VOCs compared with controls. Ten VOCs were identified through gas chromatography and mass spectrometry (GC-MS), of which 2-(methylamino)-ethanol (2-ME) had strong fumigant activity against J2s of M. incognita, with an LC50 value of 1.5 mM at 12 h. These results indicate that S1-10 represents a potential novel biocontrol agent for RKNs.


Assuntos
Bacillus pumilus , Praguicidas , Tylenchoidea , Compostos Orgânicos Voláteis , Animais , Compostos Orgânicos Voláteis/farmacologia , Compostos Orgânicos Voláteis/química , Etanol
6.
Gastrointest Endosc ; 95(6): 1138-1146.e2, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34973966

RESUMO

BACKGROUND AND AIMS: The quality of EGD is a prerequisite for a high detection rate of upper GI lesions, especially early gastric cancer. Our previous study showed that an artificial intelligence system, named intelligent detection endoscopic assistant (IDEA), could help to monitor blind spots and provide an operation score during EGD. Here, we verified the effectiveness of IDEA to help evaluate the quality of EGD in a large-scale multicenter trial. METHODS: Patients undergoing EGD in 12 hospitals were consecutively enrolled. All hospitals were equipped with IDEA developed using deep convolutional neural networks and long short-term memory. Patients were examined by EGD, and the results were recorded by IDEA. The primary outcome was the detection rate of upper GI cancer. Secondary outcomes were part scores, total scores, and endoscopic procedure time, which were analyzed by IDEA. RESULTS: A total of 17,787 patients were recruited. The total detection rate of cancer-positive cases was 1.50%, ranging from .60% to 3.94% in each hospital. The total detection rate of early cancer-positive cases was .36%, ranging from .00% to 1.58% in each hospital. The average total score analyzed by IDEA ranged from 64.87 ± 16.87 to 83.50 ± 9.57 in each hospital. The cancer detection rate in each hospital was positively correlated with total score (r = .775, P = .003). Similarly, the early cancer detection rate was positively correlated with total score (r = .756, P = .004). CONCLUSIONS: This multicenter trial confirmed that the quality of the EGD result is positively correlated with the detection rate of cancer, which can be monitored by IDEA. (Clinical trial registration number: ChiCTR2000029001.).


Assuntos
Neoplasias Gastrointestinais , Neoplasias Gástricas , Inteligência Artificial , Endoscopia , Endoscopia do Sistema Digestório/métodos , Humanos , Redes Neurais de Computação , Neoplasias Gástricas/diagnóstico
7.
Analyst ; 147(18): 4008-4013, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36001020

RESUMO

Acetylcholinesterase (AChE) is an essential serine hydrolase associated with neurodegenerative diseases and serves as a biomarker. In this work, a ratiometric fluorescence strategy for the sensitive assay of AChE activity is developed based on the decomposition of MnO2 by the enzymatic hydrolysis product and DNAzyme-mediated strand cleavage. The sensing system is termed as MnO2/DNAzyme. DNAzyme locked by H2 strands is inactive in the absence of AChE. The fluorescence emission of fluorescein amidite (FAM)-labeled DNA (DNA-F) at 518 nm is quenched by neutral red (NR) and the fluorescence of NR at 632 nm is simultaneously enhanced due to fluorescence resonance energy transfer (FRET). The presence of AChE triggers the hydrolysis of the substrate acetylcholine (ATCh) to enzymatic thiocholine (TCh), which reduces MnO2 nanowires to Mn2+ and releases the attached H1 strands into the solution. The H1 strands hybridize with H2 strands through the strand displacement reaction. Meanwhile, the activated DNAzyme cleaves the RNA nucleotide of the DNA-F signal probe to release FAM. The fluorescence of FAM at 518 nm is thus recovered, corresponding to a decrement of NR emission at 632 nm owing to the blocking of FRET. The fluorescence ratio of F518/F632 serves as a signal readout for the AChE assay within 5 × 10-4-10 U mL-1, with a limit of detection (LOD) of 2.7 × 10-4 U mL-1. The feasibility of this method was demonstrated by the measurement of AChE activity in human blood, which reveals its promising potential in clinical assays.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Acetilcolinesterase , Técnicas Biossensoriais/métodos , DNA/química , DNA Catalítico/química , Fluoresceína , Fluorescência , Humanos , Compostos de Manganês/química , Óxidos/química
8.
Anal Chem ; 93(44): 14900-14906, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34714045

RESUMO

Acetylcholinesterase (AChE) plays crucial roles in the nervous system, and thus the reliable assay of its activity is of great significance for the diagnosis of nervous diseases. In this work, we report a fluorescent sensing platform with silicon quantum dots (Si-QDs) as a fluorescence oscillator and nano iron oxyhydroxide (α-, ß-, and γ-FeOOH) as a quencher for the assay of AChE. FeOOH with α-, ß-, and γ-crystal forms quenches the fluorescence of Si-QDs at λex/λem = 350/438 nm, which is retrieved in the presence of AChE and its substrate acetylthiocholine (ATCh) to provide an off-on strategy with a high signal/noise ratio. It is interesting that the sensitivity of AChE sensing is closely related to the crystal forms of FeOOH, with the highest sensitivity by adopting α-FeOOH as the quencher. A linear calibration is achieved within 0.02-1.4 U/L along with a limit of detection of 0.016 U/L. The sensing strategy was demonstrated by the AChE assay in human blood, plasma, and hemocytes.


Assuntos
Acetilcolinesterase , Pontos Quânticos , Acetiltiocolina , Fluorescência , Humanos , Silício
9.
Arch Microbiol ; 203(9): 5363-5371, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34386827

RESUMO

A novel mycelium-forming actinomycete strain, designated YIM S01255T were isolated from a salt lake. Optimal growth occurred in the presence of 0-5.0% (w/v) NaCl, at pH 7.0-8.0, and at 37 °C. Strain YIM S01255T contained meso-diaminopimelic acid as the diagnostic diamino acid, and glucose, galactose and arabinose as the whole-cell sugars. The major fatty acid (> 5.0%) were iso-C16:0, iso-C16:1H and iso-C15:0. The major menaquinone were MK-9(H4) and MK-8(H4). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylinositolmannoside and phosphatidylinositol. The DNA G + C content was 70.7 mol%. The 16S rRNA gene sequence of the strain showed high similarity to members of genera in the family Pseudonocardiaceae with values less than 95.8%, and most closely related to the genus Amycolatopsis. Both of phylogenetic analysis based on 16S rRNA gene sequences and the up-to-date bacterial genome sequences analysis revealed that strains YIM S01255T and Prauserella shujinwangii XJ46T formed a distinct monophyletic clade and was separated from the other members within the family Pseudonocardiaceae. The average nucleotide identity (ANI) values and digital DNA-DNA hybridization (dDDH) between the two strains were 81.0% and 40.6%, respectively. The distinctive polyphasic evidences differentiated YIM S01255T from members of the family Pseudonocardiaceae, so strain YIM S01255T is considered to represent a novel species of a novel genus of the family Pseudonocardiaceae, for which the name Qaidamihabitans albus gen. nov., sp. nov. is proposed. The type strain of genus Qaidamihabitans is YIM S01255T (= KCTC 49476T = CGMCC 4.7684T). Moreover, Prauserella shujinwangii is also proposed to being transferred into the genus Qaidamihabitans as Qaidamihabitans shujinwangii comb. nov. (type strain XJ46T = CGMCC 4.7125T = JCM 19736T).


Assuntos
Ácidos Graxos , Fosfolipídeos , Actinobacteria , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2
10.
Anal Bioanal Chem ; 413(20): 5161-5168, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34327562

RESUMO

Zinc ion (Zn2+) is a necessary transition metal ion in the human body and plays a vital role in biological systems. Therefore, it is meaningful for rapid, sensitive, and specific detection of Zn2+. Herein, a "switch-on" fluorescence sensing platform for the detection of Zn2+ was successfully established. In this work, we report an optical nanoprobe with amino functional groups based on porphyrin metal-organic frameworks (PCN-NH2) through a simple treatment method. The modification of the salicylaldehyde (SA) through the C=N acts as a quencher of PCN-NH2 and the ligand of Zn2+ can effectively inhibit the fluorescence emission of PCN-NH2. The complex of porphyrin-based metal-organic framework and salicylaldehyde (PCN/SA) acts as the fluorescence sensing probe. The presence of Zn2+ results in the new emission peak at 448 nm due to the formation of a complex between Zn2+ and SA. The corresponding fluorescence signal changes were used to accurately detect the concentration of Zn2+. The fluorescence sensing platform shows advantages, including rapid response, high sensitivity, and excellent specificity with a linear detection range of Zn2+ between 0.1 and 250 µM, and a low detection limit (LOD) of 0.07 µM. And the feasibility of the method was verified for the quantification of Zn2+ in cell lysate, environmental water, and plasma.


Assuntos
Fluorescência , Porfirinas/química , Zinco/química , Aldeídos/química , Corantes Fluorescentes , Estruturas Metalorgânicas
11.
Eur J Vasc Endovasc Surg ; 59(6): 1000-1010, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31879145

RESUMO

OBJECTIVE: Thoracic aortic dissection (TAD) has a high mortality rate. Intermittent hypoxia (IH) triggers both harmful and beneficial effects in numerous physiological systems. The effects of IH on TAD development were explored in a mouse model. METHODS: ß-Aminopropionitrile monofumarate (BAPN) was used to induce TAD in C57BL/6 mice. Three week old male mice were treated with 1 g/kg/day BAPN in drinking water for four weeks and simultaneously subjected to IH (n = 30) (21%-5% O2, 90 s/cycle, 10 h/day, IH + BAPN group) or normoxia (n = 30) (21% O2, 24 h/day, BAPN group). Human VSMCs (HUASMCs) exposed to IH (30 min, 5% O2)/re-oxygenation (30 min, 21% O2) cycles with a maximum of 60 min/cycle to detect the effect of IH on HIF-1α and LOX via HIF-1α-siRNA. RESULTS: It was found that BAPN administration significantly increased the lumen size and wall thickness of aortas compared with the normal group, but was significantly reversed by IH exposure. Additionally, IH exposure significantly increased the survival rate of BAPN induced TAD (70% vs. 40%). Furthermore, IH exposure reduced BAPN induced elastin breaks and apoptosis of vascular smooth muscle cells. IH exposure also reversed BAPN induced upregulation of inflammation and extracellular matrix (ECM) degradation. Real time polymerase chain reaction (RT-PCR) confirmed that IH inhibited inflammation and ECM degradation related genes interleukin (IL)-1ß, IL-6, cathepsin S (Cat S), and matrix metalloproteinase 9 (MMP-9), but upregulated the ECM synthesis related genes lysyl oxidase (LOX) and collagen type I alpha2 (Col1a2) compared with the BAPN group. In vitro results suggest that IH promotes the expression of LOX via HIF-1α. CONCLUSION: The results suggest that IH alleviates BAPN induced TAD in C57BL/6 mice.


Assuntos
Aorta Torácica/fisiopatologia , Aneurisma da Aorta Torácica/terapia , Dissecção Aórtica/terapia , Hipóxia/fisiopatologia , Pós-Condicionamento Isquêmico/métodos , Aminopropionitrilo/análogos & derivados , Aminopropionitrilo/toxicidade , Dissecção Aórtica/etiologia , Animais , Aorta Torácica/citologia , Aorta Torácica/efeitos dos fármacos , Aneurisma da Aorta Torácica/induzido quimicamente , Aneurisma da Aorta Torácica/complicações , Modelos Animais de Doenças , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
12.
Entropy (Basel) ; 22(12)2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33419330

RESUMO

As a fundamental infrastructure of energy supply for future society, energy Internet (EI) can achieve clean energy generation, conversion, storage and consumption in a more economic and safer way. This paper demonstrates the technology principle of advanced adiabatic compressed air energy storage system (AA-CAES), as well as analysis of the technical characteristics of AA-CAES. Furthermore, we propose an overall architectural scheme of a clean energy router (CER) based on AA-CAES. The storage and mutual conversion mechanism of wind and solar power, heating, and other clean energy were designed to provide a key technological solution for the coordination and comprehensive utilization of various clean energies for the EI. Therefore, the design of the CER scheme and its efficiency were analyzed based on a thermodynamic simulation model of AA-CAES. Meanwhile, we explored the energy conversion mechanism of the CER and improved its overall efficiency. The CER based on AA-CAES proposed in this paper can provide a reference for efficient comprehensive energy utilization (CEU) (93.6%) in regions with abundant wind and solar energy sources.

13.
Anal Chem ; 91(24): 15866-15872, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31756075

RESUMO

The combination of gold nanoclusters (AuNCs) and nanomaterial-based quencher creates an innovative method for sensors design. In this work, we report a fluorescent sensing platform for sensitive detection of butyrylcholinesterase (BChE). The fluorescence of AuNCs can be quenched by iron oxyhydroxide (FeOOH) nanomaterials. In the presence of BChE and acetylthiocholine (ATCh), nano-FeOOH can be effectively decomposed by the enzymatic hydrolysate (thiocholine), leading to the recovery of AuNCs fluorescence. The Au/FeOOH exhibits the highest fluorescence quenching efficiency compared with other transition metal oxyhydroxide-based sensing systems, e.g., Au/CoOOH and Au/NiOOH. The corresponding fluorescence recovery efficiency is also the best for Au/FeOOH. The large surface area of nanomaterials and thin nanostructure provide a favorable platform for the reaction of enzymatic hydrolysate and eventually improve the high sensitivity of the probe. A linear detection range for BChE is achieved within 5-100 ng mL-1 along with a detection limit of 4 ng mL-1. By taking advantage of the high sensitivity, the Au/FeOOH was successfully used for BChE quantification in 2 µL of finger blood.


Assuntos
Butirilcolinesterase/análise , Compostos Férricos/química , Ouro/química , Nanopartículas Metálicas/química , Espectrometria de Fluorescência/métodos , Butirilcolinesterase/sangue , Humanos , Limite de Detecção , Nanoestruturas/química , Reprodutibilidade dos Testes
14.
Analyst ; 144(14): 4175-4179, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31237576

RESUMO

In this work, we report a facile, sensitive, selective, and reproducible DNA impedimetric sensor device. We demonstrate that, combined with exonuclease III, the easily prepared electrochemically reduced graphene oxide (rGO) could be a desirable platform to amplify signals in electrochemical impedance spectroscopy for ultrasensitive DNA detection. Guided by enzyme assisted target recycling, efficient interfacial tuning can be obtained, from the situation with high impedance caused by single-stranded DNA probes directly adsorbed onto rGO to the one with low impedance due to the continuous desorption of target-probe DNA hybrids and the consequent digestion of DNA probes. Just a few DNA targets can specifically trigger the enzymatic digestion of a large number of DNA probes. It is the excellent electrical conductivity of rGO that further enlarges the changes of electron transfer resistance after the removal of DNA probes. As a result of synergistically combining both enzymatic and electrical amplification, the enlarged changes of impedimetric signals can be measured to sensitively report DNA targets. The specificity has been guaranteed by the intrinsic recognition of hybrids through both rGO and exonuclease III. A limit of detection as low as 10 aM target DNA in the matrix of cell culture medium, as well as a wide linear range and good discrimination of mismatched sequences even at the one-base level, suggests its great application prospect in biosensing and biomedical analysis. It also has other advantages including easy operation, low cost, and convenient regeneration, with more competitive performance in developing impedimetric biosensors.


Assuntos
DNA/análise , Técnicas Biossensoriais/métodos , DNA/química , DNA/genética , Sondas de DNA/genética , Espectroscopia Dielétrica/métodos , Exodesoxirribonucleases/química , Grafite/química , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/métodos , Hibridização de Ácido Nucleico
15.
Angew Chem Int Ed Engl ; 58(51): 18394-18398, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31628706

RESUMO

An exceptionally strong solvation effect of dimethyl sulfoxide (DMSO) on I2 is identified by the largest shift observed so far of the I2 Raman peak with respect to I2 vapor and by elongated I-I bond lengths in first-principles molecular-dynamics simulations. This effect together with strong binding by an RuO2 surface to I2 is found to invert the direction of the reaction I- +I2 ⇌I3 - to the left-hand side. Inspired by this finding, we prepared a Li-O2 battery with the Li/DMSO+LiI/RuO2 structure. The synergic action of DMSO and RuO2 on I2 is found to suppress the shuttle effect of the redox mediator (RM) by anchoring I2 molecules, the oxidation product of the RM. Significantly enhanced stability is demonstrated over 100 cycles at charging voltage below 3.65 V.

16.
BMC Cancer ; 18(1): 88, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29357836

RESUMO

BACKGROUND: Scavenger receptor class B type I (SR-BI) has been reported to be involved in carcinogenesis of several human cancers. However, it is currently unknown whether SR-BI plays a role in clear cell renal cell carcinoma (ccRCC). Here, we aimed to evaluate a tumor promotive mechanism for SR-BI in ccRCC. METHODS: The expression of SR-BI was evaluated by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blot and immunohistochemistry (IHC) in ccRCC tissues and cell lines. Lipid droplets in ccRCC tissues and normal kidney tissues were examined by Oil Red O (ORO) and hematoxylin-eosin (HE) staining. The correlation between SR-BI mRNA levels and clinicopathological features was analyzed by Pearson's chi-square test or Fisher's exact test. Kaplan-Meier analysis and Cox model were used to evaluate the difference in progression-free survival (PFS) associated with expression of SR-BI. Inhibition of SR-BI was conducted by using small interfering RNA (siRNA). In vitro assays were performed to assess the impact of SR-BI knockdown on cell biological behaviors. High density lipoprotein (HDL)-cholesterol content in ccRCC cells and extracellular media was also measured after transfection with siRNA. RESULTS: The expression of SR-BI was markedly up-regulated in ccRCC tissues and tumor cell lines. ORO and HE staining revealed huge amounts of lipid droplets accumulation in ccRCC. Clinical analysis showed that over-expression of SR-BI was positively associated with tumor size, grade, distant metastasis and inversely correlated with PFS. Furthermore, SR-BI was proved to be an independent prognostic marker in ccRCC patients. The inhibition of SR-BI attenuated the tumorous behaviors of ccRCC cells, expression of metastasis and AKT pathway related proteins. The content of HDL-cholesterol was reduced in cells while increased in extracellular media after transfection with si-SR-BI. CONCLUSIONS: Our results demonstrate that SR-BI functions as an oncogene and promotes progression of ccRCC. SR-BI may serve as a potential prognostic biomarker and therapeutic target for ccRCC.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Prognóstico , Receptores Depuradores Classe B/genética , Adulto , Idoso , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , HDL-Colesterol/genética , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , RNA Mensageiro/genética
17.
Nucleic Acids Res ; 44(17): 8229-40, 2016 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-27325747

RESUMO

DNA polymerase ε (Pol ε) is a replicative DNA polymerase with an associated 3'-5' exonuclease activity. Here, we explored the capacity of Pol ε to perform strand displacement synthesis, a process that influences many DNA transactions in vivo We found that Pol ε is unable to carry out extended strand displacement synthesis unless its 3'-5' exonuclease activity is removed. However, the wild-type Pol ε holoenzyme efficiently displaced one nucleotide when encountering double-stranded DNA after filling a gap or nicked DNA. A flap, mimicking a D-loop or a hairpin structure, on the 5' end of the blocking primer inhibited Pol ε from synthesizing DNA up to the fork junction. This inhibition was observed for Pol ε but not with Pol δ, RB69 gp43 or Pol η. Neither was Pol ε able to extend a D-loop in reconstitution experiments. Finally, we show that the observed strand displacement synthesis by exonuclease-deficient Pol ε is distributive. Our results suggest that Pol ε is unable to extend the invading strand in D-loops during homologous recombination or to add more than two nucleotides during long-patch base excision repair. Our results support the hypothesis that Pol ε participates in short-patch base excision repair and ribonucleotide excision repair.


Assuntos
DNA Polimerase II/metabolismo , DNA Fúngico/biossíntese , Saccharomyces cerevisiae/enzimologia , DNA Fúngico/química , Conformação de Ácido Nucleico , Nucleotídeos/metabolismo , Subunidades Proteicas/metabolismo , Cloreto de Sódio/farmacologia , Especificidade por Substrato/efeitos dos fármacos
18.
Arch Microbiol ; 199(9): 1277-1281, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28624973

RESUMO

A novel Gram-positive, aerobe, moderately halophilic bacterium was isolated from saline soil of Aiding lake in Xinjiang, north-west of China, designated strain YIM 98001T. Cells were rod-shaped, motile and grew at 5-20% (w/v) NaCl (optimum 10%), pH 6-10 (optimum pH 7.0) and 4-45 °C (optimum 37 °C). The major cellular fatty acids were anteiso C15:0, anteiso C17:0, iso C15:0. The predominant respiratory quinone was MK-7. Diphosphatidylglycerol, phosphatidylglycerol, phosphoglycolipid were the major polar lipids. Meso-diaminopimelic acid was the diagnostic diamino acid of the cell-wall peptidoglycan. The G+C content was 36.46 mol%. 16S rRNA gene sequence analysis showed that the strain belongs to the family Bacillaceae, with the highest sequence similarity to the type strain Gracilibacillus thailandensis TP2-8T (96.84%), followed by Gracilibacillus saliphilus YIM 91119T (96.78%) and Gracilibacillus ureilyticus MF38T (96.57%), thus confirming the affiliation of strain YIM 98001T to the genus Gracilibacillus. The polyphasic approach indicates that strain YIM 98001T represents a novel species of the genus Gracilibacillus, for which the name Gracilibacillus aidingensis is proposed. The type strain is YIM 98001T (=KCTC 42683T = DSMZ 104330T).


Assuntos
Bacillaceae , DNA Bacteriano/genética , Bacillaceae/classificação , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases/genética , Parede Celular/química , China , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Lagos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo , Microbiologia do Solo
19.
Arch Microbiol ; 199(9): 1237-1242, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28577180

RESUMO

A novel Gram-negative rod, endophytic bacterium, designated strain TMCC 8258T, was isolated from the root of Camellia sinensis collected from Puer, south-west China. Comparative 16S rRNA gene sequence analysis showed that the strain belongs to the family Sphingobacteriaceae and a neighbour-joining phylogenetic tree suggested that strain TMCC 8258T formed a cluster with the type strain of Olivibacter ginsengisoli (showed the highest 16S rRNA gene sequence similarity of 95.8%). Chemotaxonomic data [major fatty acid iso-C15:0, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), iso-C17:0 3-OH and major respiratory quinone MK-7] confirmed the affiliation of strain TMCC 8258T to the genus Olivibacter. The G + C content was 39.1 mol %. The results of the phylogenetic analysis, together with the physiological, morphological and biochemical tests, suggested that strain TMCC 8258T should be classified as representing a novel species of the genus Olivibacter, for which the name Olivibacter flavus is proposed. The type strain is TMCC 8258T (=CGMCC 1.16141 = KCTC 42683).


Assuntos
Bacteroidetes , Camellia sinensis/microbiologia , DNA Bacteriano/genética , Raízes de Plantas/microbiologia , Técnicas de Tipagem Bacteriana , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Composição de Bases/genética , China , Ácidos Graxos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
20.
J Immunol ; 195(10): 4802-9, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26475925

RESUMO

Diverse clinical factors, including intestinal ischemia, contribute to acute lung injury (ALI), which has up to a 40% mortality rate. During the development of lung injury an immune response is elicited that exacerbates the lung insult. Neutrophils have been well studied in mediating the pulmonary insults through an assortment of mechanisms, such as release of granule contents and production of proinflammatory cytokines due to the overactivation of complement and cytokines. In this study, we found that enhanced endoplasmic reticulum (ER) stress was observed in infiltrated neutrophils in the early stage of an ALI mice model. In neutrophils, complement 5a (C5a) inspires strong ER stress through inositol-requiring kinase 1a and, to a less extent, the protein kinase R-like ER kinase signaling pathway. The granule release induced by C5a was ER stress mediated. Knowkdown of X-box-binding protein 1, a downstream signaling molecule of inositol-requiring kinase 1a, impaired granule release, based on myeloperoxidase production. Further analysis revealed that C5a induced ER stress by binding to C5a receptor in neutrophils. Using xbp(f/f) MRP8-cre mice in which X-box-binding protein 1 is deficient specifically in neutrophils and ER stress is deprived, we confirmed that ER stress in neutrophils was required for granule release in vivo and led to ALI, whereas dampening ER stress in neutrophils substantially alleviated ALI. Taken together, our results demonstrated that C5a receptor-mediated ER stress induced granule release in neutrophils, contributing to the development of ALI. This novel mechanism suggests a new potential therapeutic target in autophagy regulation for ALI.


Assuntos
Lesão Pulmonar Aguda/imunologia , Estresse do Retículo Endoplasmático/imunologia , Pulmão/imunologia , Neutrófilos/imunologia , Traumatismo por Reperfusão/imunologia , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/patologia , Animais , Complemento C5a/genética , Complemento C5a/metabolismo , Estresse do Retículo Endoplasmático/genética , Endorribonucleases/genética , Endorribonucleases/imunologia , Pulmão/patologia , Camundongos , Camundongos Transgênicos , Neutrófilos/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia
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