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1.
Talanta ; 272: 125784, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38364555

RESUMEN

Fat mass and obesity-associated protein (FTO) is a crucial eraser of RNA N6- methyladenosine (m6A) modification, and abnormal FTO expression level is implicated in pathogenesis of numerous cancers. Herein, we demonstrate the construction of a label-free fluorescent biosensor for homogeneous detection of m6A eraser FTO in breast cancer tissues. When FTO is present, it specifically erases the methyl group in m6A, inducing the cleavage of demethylated DNA by endonuclease DpnII and the generation of a single-stranded DNA (ssDNA) with a 3'-hydroxyl group. Subsequently, terminal deoxynucleotidyl transferase (TdT) promotes the incorporation of dTTPs into the ssDNA to obtain a long polythymidine (T) DNA sequence. The resultant long poly (T) DNA sequence can act as a template to trigger hyperbranched strand displacement amplification (HSDA), yielding numerous DNA fragments that may be stained by SYBR Gold to produce an enhanced fluorescence signal. This biosensor processes ultrahigh sensitivity with a detection limit of 1.65 × 10-10 mg/mL (2.6 fM), and it can detect the FTO activity in a single MCF-7 cell. Moreover, this biosensor can screen the FTO inhibitors, evaluate enzyme kinetic parameters, and discriminate the FTO expression levels in the tissues of breast cancer patients and healthy persons.


Asunto(s)
Técnicas Biosensibles , Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/genética , ADN , ADN de Cadena Simple/genética , ARN , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética
2.
JAMA Intern Med ; 184(3): 291-299, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38285562

RESUMEN

Importance: Electronic cigarettes (ECs) are often used by smokers as an aid to stopping smoking, but evidence is limited regarding their efficacy compared with nicotine replacement therapy (NRT), and no evidence is available on how their efficacy compares with that of varenicline. Objective: To evaluate whether ECs are superior to NRT and noninferior to varenicline in helping smokers quit. Design, Setting, and Participants: This was a randomized clinical trial conducted at 7 sites in China and including participants who were smoking at least 10 cigarettes per day and motivated to quit, not using stop-smoking medications or EC, and willing to use any of the study products. Participants were first recruited in May 2021, and data analysis was conducted in December 2022. Interventions: A cartridge-based EC (30 mg/mL nicotine salt for 2 weeks and 50 mg/mL after that), varenicline (0.5 mg, once a day for 3 days; 0.5 mg, twice a day for 4 days; and 1 mg, twice a day, after that), and 2 mg (for smokers of ≤20 cigarettes per day) or 4 mg (>20 cigarettes per day) nicotine chewing gum, all provided for 12 weeks and accompanied by minimal behavioral support (an invitation to join a self-help internet forum). Main Outcomes and Measures: The primary outcome was sustained abstinence from smoking at 6 months as validated by an expired-air carbon monoxide reading (<8 parts per million). Participants lost to follow-up were included as nonabstainers. Results: Of 1068 participants, 357 (33.5%) were female, and the mean (SD) age was 33.9 (3.1) years. A total of 409 (38.3%), 409 (38.3%), and 250 (23.4%) participants were randomized to the EC, varenicline, and NRT arms, respectively. The 6-month biochemically validated abstinence rates were 15.7% (n = 64), 14.2% (n = 58), and 8.8% (n = 22) in the EC, varenicline, and NRT study arms, respectively. The quit rate in the EC arm was noninferior to the varenicline arm (absolute risk reduction, 1.47%; 95% CI, -1.41% to 4.34%) and higher than in the NRT arm (odds ratio, 1.92; 95% CI, 1.15-3.21). Treatment adherence was similar in all study arms during the initial 3 months, but 257 participants (62.8%) in the EC arm were still using ECs at 6 months, with no further use in the 2 other study arms. The most common adverse reactions were throat irritation (32 [7.8%]) and mouth irritation (28 [6.9%]) in the EC arm, nausea (36 [8.8%]) in the varenicline arm, and throat irritation (20 [8.0%]) and mouth irritation (22 [8.8%]) in the NRT arm. No serious adverse events were recorded. Conclusions and Relevance: The results of this randomized clinical trial found that when all treatments were provided with minimal behavior support, the efficacy of EC was noninferior to varenicline and superior to nicotine chewing gum. Trial Registration: Chinese Clinical Trial Registry: ChiCTR2100048156.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Chicles de Nicotina , Cese del Hábito de Fumar , Femenino , Humanos , Adulto , Masculino , Cese del Hábito de Fumar/métodos , Vareniclina/uso terapéutico , Agonistas Nicotínicos/efectos adversos , Dispositivos para Dejar de Fumar Tabaco , Fumar
3.
Zhongguo Zhong Yao Za Zhi ; 48(19): 5377-5388, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-38114127

RESUMEN

This study aimed to evaluate the efficacy and safety of Chaihuang Granules in the treatment of upper respiratory tract infection in children. The databases such as CNKI, Wanfang, VIP, SinoMed, Cochrane Library, PubMed, EMbase, Web of Science, Chinese Clinical Trial Registry, and ClinicalTrials.gov were searched for randomized controlled trial(RCT) of Chaihuang Granules for the treatment of upper respiratory tract infection in children, and supplemented by manual searching of gray literature. Two investigators independently screened the literature, extracted data, and assessed the methodological quality. Meta-analysis was performed using RevMan 5.4 software, trial sequential analysis was conducted using TSA 0.9.5.10 Beta software, and evidence quality evaluation was carried out using GRADE profiler 3.6.1 software. Eighteen RCTs involving 2 459 patients(1 262 in the treatment group and 1 197 in the control group) were included. Meta-analysis showed that compared with conventional therapy alone, Chaihuang Granules significantly improved the total effective rate(RR=1.18, 95%CI[1.15, 1.22], P<0.000 01), reduced the disappearance time of symptoms/signs(MD=-1.39, 95%CI[-1.66,-1.12], P<0.000 01), improved cytokine levels(MD=-2.40, 95%CI[-3.80,-1.00], P=0.000 8), improved humoral immune levels(MD=0.75, 95%CI[0.60, 0.90], P<0.000 01), and reduced the recurrence rate(MD=-2.11, 95%CI[-2.98,-1.25], P<0.000 01). However, the incidence of adverse reactions was not increased(RR=0.94, 95%CI[0.59, 1.49], P=0.78). Subgroup analysis showed that:(1) both Chaihuang Granules used alone(RR=1.19, 95%CI[1.11, 1.27], P<0.000 01) and in combination with other therapies(RR=1.18, 95%CI[1.14, 1.22], P<0.000 01) effectively improved the total effective rate.(2) In terms of symptoms/signs disappearance time, Chaihuang Granules effectively reduced the duration of fever(MD=-1.18, 95%CI[-1.78,-0.58], P=0.000 1), cough with sputum(MD=-1.82, 95%CI[-2.38,-1.25], P<0.000 01), cough(MD=-1.31, 95%CI[-1.89,-0.74], P<0.000 01), sore throat(MD=-1.57, 95%CI[-2.25,-0.89], P<0.000 01), and lung rales(MD=-1.49, 95%CI[-2.06,-0.92], P<0.000 01).(3) Regarding cytokine levels, Chaihuang Gra-nules effectively improved the levels of interleukin(IL)-2(MD=-0.94, 95%CI[-1.16,-0.72], P<0.000 01), IL-6(MD=-4.71, 95%CI[-6.39,-3.03], P<0.000 01), and tumor necrosis factor-α(TNF-α)(MD=-2.07, 95%CI[-2.43,-1.71], P<0.000 01).(4) In terms of cellular immune levels, Chaihuang Granules effectively improved the levels of CD3~+(MD=4.11, 95%CI[1.53, 6.69], P=0.002), CD4~+(MD=4.21, 95%CI[1.69, 6.73], P=0.001), CD8~+(MD=-2.65, 95%CI[-3.93,-1.37], P<0.000 1), and CD4~+/CD8~+(MD=0.25, 95%CI[0.14, 0.37], P<0.000 1).(5) In terms of humoral immune levels, Chaihuang Granules effectively improved the levels of IgA(MD=0.44, 95%CI[0.23, 0.64], P<0.000 1), IgM(MD=0.31, 95%CI[0.15, 0.46], P=0.000 1), and IgG(MD=2.02, 95%CI[1.60, 2.43], P<0.000 01). Trial sequential analysis showed that the cumulative Z-curve of the total effective rate crossed the boundary value, further confirming its clinical efficacy. The GRADE evidence quality evaluation showed that the evidence quality of the above outcome indicators was low or very low, and the recommendation strength was weak. Compared to conventional therapy alone, Chaihuang Granules can effectively improve the total effective rate of treatment, alle-viate symptoms and signs of upper respiratory tract infection in children, improve inflammatory conditions, enhance immune function, and reduce the recurrence rate. Due to the limited quality of the included studies, high-quality RCT is still needed to provide evidence support for the above conclusions.


Asunto(s)
Medicamentos Herbarios Chinos , Infecciones del Sistema Respiratorio , Niño , Humanos , Medicamentos Herbarios Chinos/uso terapéutico , Resultado del Tratamiento , Ensayos Clínicos como Asunto , Infecciones del Sistema Respiratorio/tratamiento farmacológico
4.
Nat Commun ; 14(1): 6666, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37863924

RESUMEN

Highly effective and selective noble metal-free catalysts attract significant attention. Here, a single-atom iron catalyst is fabricated by saturated adsorption of trace iron onto zeolitic imidazolate framework-8 (ZIF-8) followed by pyrolysis. Its performance toward catalytic transfer hydrogenation of furfural is comparable to state-of-the-art catalysts and up to four orders higher than other Fe catalysts. Isotopic labeling experiments demonstrate an intermolecular hydride transfer mechanism. First principles simulations, spectroscopic calculations and experiments, and kinetic correlations reveal that the synthesis creates pyrrolic Fe(II)-plN3 as the active center whose flexibility manifested by being pulled out of the plane, enabled by defects, is crucial for collocating the reagents and allowing the chemistry to proceed. The catalyst catalyzes chemoselectively several substrates and possesses a unique trait whereby the chemistry is hindered for more acidic substrates than the hydrogen donors. This work paves the way toward noble-metal free single-atom catalysts for important chemical reactions.

5.
Anal Chim Acta ; 1279: 341796, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37827689

RESUMEN

The METTL3/14 complex is an important RNA N6-Methyladenosine (m6A) methyltransferase in organisms, and the abnormal METTL3/14 complex activity is associated with the pathogenesis and various cancers. Sensitive detection of METTL3/14 complex is essential to tumor pathogenesis study, cancer diagnosis, and anti-cancer drug discovery. However, traditional methods for METTL3/14 complex assay suffer from poor specificity, costly antibodies, unstable RNA substrates, and low sensitivity. Herein, we construct a single quantum dot (QD)-based förster resonance energy transfer (FRET) biosensor for sensitive detection of METTL3/14 complex activity. In the presence of METTL3/14 complex, it catalyzes the methylation of adenine in the substrate probe, leading to the formation of m6A that protects the substrate probes from MazF-mediated cleavage. The hybridization of methylated DNA substrate with biotinylated capture probe initiates polymerization reaction to obtain a biotinylated double-stranded DNA (dsDNA) with the incorporation of numerous Cy5 fluorophores. Subsequently, the Cy5-incorporated dsDNA can self-assembly onto the 605QD surface to form the 605QD-dsDNA-Cy5 nanostructure, causing FRET between 605QD donor and Cy5 acceptor. This biosensor has excellent sensitivity with a limit of detection (LOD) of 3.11 × 10-17 M, and it can measure the METTL3/14 complex activity in a single cell. Moreover, this biosensor can be used to evaluate the METTL3/14 complex kinetic parameters and screen potential inhibitors. Furthermore, it can differentiate the METTL3/14 complex expression in healthy human tissues and breast cancer patient tissues, providing a powerful tool for cancer pathogenesis study, clinical diagnosis, prognosis monitoring, and drug discovery.


Asunto(s)
Técnicas Biosensibles , Neoplasias de la Mama , Puntos Cuánticos , Humanos , Femenino , Puntos Cuánticos/química , Neoplasias de la Mama/diagnóstico , ADN/química , Metiltransferasas , ARN
6.
Front Immunol ; 13: 967506, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35967334

RESUMEN

Background: Patients with systemic lupus erythematosus (SLE) are at increased risk of cardiovascular disease (CVD) compared to the general population. However, little is known about the effects of tobacco smoking on CVD in patients with SLE. Objective: To systematically review and summarize the available literature regarding the effects of tobacco smoking on developing CVD in patients with SLE. Methods: We retrieved relevant studies from the following databases: PubMed, EMBASE, Web of Science and China National Knowledge Internet (CNKI) database. Two reviewers independently reviewed the eligible studies, assessed their validity, and extracted relevant data. Sensitivity and subgroup analyses were performed to distinguish sources of heterogeneity. Results: A total of 10 studies, which comprised 6984 participants, were included in the analysis. The overall quality of evidence was rated as moderate to low. The smoking prevalence among CVD patients was 39.28% (271/690), which was higher than 31.36% (1974/6294) among non-CVD patients. Compared with never-smokers, the risk of developing CVD in current smokers was 1.42 (95% CI: 1.21-1.66). No significant publication bias was found in our meta-analysis. Conclusions: In spite of the several negative results, this study found that current smokers with SLE have an increased risk of developing CVD, although most of the included studies were in low-to-moderate quality. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022338109.


Asunto(s)
Enfermedades Cardiovasculares , Lupus Eritematoso Sistémico , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/etiología , Humanos , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/epidemiología , Prevalencia , Fumar/efectos adversos , Fumar/epidemiología , Fumar Tabaco/efectos adversos , Fumar Tabaco/epidemiología
7.
Chem Commun (Camb) ; 58(62): 8662-8665, 2022 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-35822530

RESUMEN

We have developed a simple and rapid mix-and-read assay for the sensitive detection of O6-methylguanine DNA methyltransferase (MGMT) activity based on exonuclease III-assisted signal amplification under completely isothermal conditions (37 °C). This method is very simple and rapid (60 min) with ultrahigh sensitivity and good specificity, and it can detect MGMT activity at the single-cell level. Moreover, this method can be applied for the screening of MGMT inhibitors and the discrimination of MGMT in different cancer cells.


Asunto(s)
Guanina , O(6)-Metilguanina-ADN Metiltransferasa , ADN , Guanina/análogos & derivados , O(6)-Metilguanina-ADN Metiltransferasa/genética
8.
Dev Comp Immunol ; 135: 104490, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35793720

RESUMEN

Mammalian TAX1BP1 (TAX1 binding protein 1), originally identified as a partner of the HTLV-1 viral oncoprotein, functions in regulation of cellular cytokine production. TAX1BP1 plays an important signal transduction regulator, specifically modulating innate immune signaling pathways including NF-B and IRF3. The function of TAX1BP1, which regulates the innate immune response in mammals, has been well studied in previous reports, but the role of chicken TAX1BP1 (chTAX1) in IFN regulation and infectious bursal disease virus (IBDV) replication is still unclear. In this report, chTAX1 was successfully cloned and sub-inserted into a eukaryotic expression vector. The critical regions of chTAX1, such as LC3 binding motif, ubiquitin binding motif, are highly conserved compared to other organisms. We also found that chTAX1 inhibits IFN expression by promoting degradation of chicken MAVS (chMAVS). In addition, the distribution of chTAX1 altered and translocated to co-localize with both VP1 and VP3 after IBDV infection. Overexpression of chTAX1 promotes IBDV replication and knockdown of chTAX1 by RNA interference suppresses IBDV replication. In summary, our data initially indicate that chTAX1 is a suppressor of IFN expression as well as a promoter of IBDV replication.


Asunto(s)
Infecciones por Birnaviridae , Virus de la Enfermedad Infecciosa de la Bolsa , Interferón Tipo I , Animales , Pollos , Inmunidad Innata , Mamíferos , Replicación Viral
9.
Front Plant Sci ; 13: 860945, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35548310

RESUMEN

AtRsmD was recently demonstrated to be a chloroplast 16S rRNA methyltransferase (MTase) for the m2G915 modification in Arabidopsis. Here, its function of AtRsmD for chloroplast development and photosynthesis was further analyzed. The AtRsmD gene is highly expressed in green photosynthetic tissues. AtRsmD is associated with the thylakoid in chloroplasts. The atrsmd-2 mutant exhibited impaired photosynthetic efficiency in emerging leaves under normal growth conditions. A few thylakoid lamellas could be observed in the chloroplast from the atrsmd-2 mutant, and these thylakoids were loosely organized. Knockout of the AtRsmD gene had minor effects on chloroplast ribosome biogenesis and RNA loading on chloroplast ribosomes, but it reduced the amounts of chloroplast-encoded photosynthesis-related proteins in the emerging leaves, for example, D1, D2, CP43, and CP47, which reduced the accumulation of the photosynthetic complex. Nevertheless, knockout of the AtRsmD gene did not cause a general reduction in chloroplast-encoded proteins in Arabidopsis grown under normal growth conditions. Additionally, the atrsmd-2 mutant exhibited more sensitivity to lincomycin, which specifically inhibits the elongation of nascent polypeptide chains. Cold stress exacerbated the effect on chloroplast ribosome biogenesis in the atrsmd-2 mutant. All these data suggest that the AtRsmD protein plays distinct regulatory roles in chloroplast translation, which is required for chloroplast development and chloroplast function.

10.
Front Pharmacol ; 13: 764930, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35479315

RESUMEN

Background: No effective medication is available for symptomatic bradyarrhythmia, particularly in low socioeconomic status (SES) population. Objective: To explore the safety and efficacy of Yuanjiang decoction, a traditional Chinese medicinal prescription, for symptomatic bradyarrhythmia on a compassionate-use basis. Methods: This compassionate-use study was conducted in Beijing, China between January 2019 and January 2020. Eligible participants were recruited and treated with Yuanjiang decoction (composed of 6 Chinese herbal medicines), 200 ml twice daily for 16 weeks. Analyses were done with the intention-to-treat (ITT) approach. The primary outcome measure was the proportion of participants who achieved a favorable treatment outcome at 16 weeks. Results: As of January 2020, 184 patients were included. After 16-weeks treatment, 12 participants were lost to contact while 21 participants were terminated from this study, with a drop-out rate of 17.93%. The most common treatment-related adverse events were xerostomia (6.52%), constipation (6.45%) and sleepiness (3.26%). The proportion of participants with favorable treatment outcome was 65.22% at 4 weeks, 59.78% at 8 weeks (OR: 1.11, 95% CI: 0.71-1.73), 61.41% at 12 weeks (OR: 1.16, 95% CI: 0.92-1.45) and 60.87% at 16 weeks (OR: 1.15, 95% CI: 0.98-1.35). In the multifactor regression analysis, the favorable treatment outcome at 16 weeks was significantly associated with completing at least 8 weeks treatment (OR: 2.053, 95% CI: 1.064-3.560), while unfavorable treatment outcome was significantly associated with an atrioventricular block (OR: 0.255, 95% CI: 0.083-0.784), current smoking (OR: 0.343, 95% CI: 0.027-0.487), and syncope in the month before treatment (OR: 0.321, 95%CI: 0.114-0.904). Conclusion: This compassionate-use study showed encouraging outcomes of treatment with Yuanjiang decoction, without serious adverse events. This study identified several key factors that may affect outcomes. These findings helped inform the design and assess the feasibility of a large-scale randomized clinical trial.

11.
Tob Induc Dis ; 20: 16, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35221859

RESUMEN

INTRODUCTION: The use of e-cigarettes has become more common in China, but the research on e-cigarettes in China, while growing, is still limited. This study examined the characteristics and patterns of e-cigarette use, and analyzed the possible mediators between cigarette cessation intention and e-cigarette use in a Chinese smoking population. METHODS: This was a cross-sectional study conducted in mainland China. By convenience sampling method, the participants were recruited from 85 major commercial streets of several large cities in China. The study interviewers completed face-to-face interviews and uploaded the completed questionnaires into the online survey platform. The participants were contacted for clarification if any problems were detected. Logistic regression yielded adjusted odds ratios (ORs) for ever use of e-cigarettes. We further conducted a mediation analysis to estimate the effect of possible mediators. RESULTS: From July to August 2020, a total of 738 smokers were invited to participate in this study; 613 smokers were identified as eligible and 609 smokers were included in this analysis. Of them, 24 (3.94%) participants were currently using e-cigarettes, and 165 (27.09%) participants have ever used e-cigarettes. The participants with younger age were more likely to have ever used e-cigarettes, ranging from 37.5% in the 18-29 years age group to 6.5% in the 60-69 years age group. After controlling for demographic characteristics and nicotine dependence, the ever use of e-cigarettes was significantly associated with younger age, higher education level, higher monthly income, previous smoking cessation attempts and quitting intention. With the mediation analysis, the education level is confirmed as a mediating factor, and approximately 42.86% of the effects were mediated through the channel of higher socioeconomic status. CONCLUSIONS: This is the first study to examine the possible mediators between cigarette cessation intention and e-cigarette use in a Chinese smoking population. The findings revealed that high socioeconomic status, particularly higher education level, was a major mediating factor.

12.
J Nat Prod ; 85(4): 963-971, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35191714

RESUMEN

Neocryptolepine derivatives have attracted great interest because of their unique cytotoxic activity. 8-Fluoroneocryptolepine (8FNC) was synthesized, and its cytotoxicity was evaluated by MTT assay in AGS gastric cancer cells and gastric mucosa GES-1 cells. 8-Fluoroneocryptolepine showed greater selectivity and cytotoxicity to AGS cells than the cisplatin (CIS) and fluorouracil (5-Fu) commonly used in clinical treatment of gastric cancer. Most importantly, we significantly improved the cytotoxic effect of 8FNC against AGS cells by structural modification and reduced the cytotoxicity against GES-1 cells compared with neocryptolepine. We further evaluated the activity of 8FNC against AGS cells in vitro. Our results indicate that 8FNC arrests the AGS cell cycle in the G2/M phase, reduces the mitochondrial membrane potential of AGS cells, and drives the initiation of apoptotic body formation in 8FNC-induced apoptosis. Moreover, 8FNC exhibits strong inhibitory effects on AGS cell migration. Studies on the molecular mechanisms of the cytotoxic activities of 8FNC revealed that it may play a significant role in the inhibitory effect on AGS human gastric cancer cells through the PI3K/AKT signaling pathway. In conclusion, 8FNC may become a promising lead compound in the development of potential clinical drug candidates for the treatment of gastric cancer.


Asunto(s)
Antineoplásicos , Neoplasias Gástricas , Antineoplásicos/química , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Fluorouracilo/farmacología , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias Gástricas/tratamiento farmacológico
13.
Materials (Basel) ; 13(11)2020 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-32503245

RESUMEN

The core part of a hybrid truss bridge is the connection joint which combines the concrete chord and steel truss-web members. To study the mechanical behavior and failure mode of steel-concrete connection joints in a hybrid truss bridge, static model tests were carried out on two connection joints with the scale of 1:3 under the horizontal load which was provided by a loading jack mounted on the vertical reaction wall. The specimen design, experimental setup and testing procedure were introduced. In the experiment, the displacement, strain level, concrete crack and experimental phenomena were factually recorded. Compared with the previous study results, the experimental results in this study demonstrated that the connection joints had the excellent bearing capacity and deformability. The minimum ultimate load and displacement of the two connection joints were 5200 kN and 59.01 mm, respectively. Moreover, the connection joints exhibited multiple failure modes, including the fracture of gusset plates, the slippage of high-strength bolts, the local buckling of compressive splice plates, the fracture of tensile splice plates and concrete cracking. Additionally, the strain distribution of the steel-concrete connection joints followed certain rules. It is expected that the findings from this paper may provide a reference for the design and construction of steel-concrete connection joints in hybrid truss bridges.

14.
Bioorg Med Chem Lett ; 28(3): 515-518, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29295796

RESUMEN

Four new diphenyl ether derivatives, sinopestalotiollides A-D (1-4), one new natural α-pyrone product (11), as well as twelve known compounds (5-1 7), were obtained from the ethyl acetate extract of the endophytic fungus Pestalotiopsis palmarum isolated from the leaves of medicinal plant Sinomenium acutum (Thunb.) Rehd et Wils. The structures were elucidated by HR-ESI-MS and NMR spectrometry data. Bioassay experiments revealed that compounds 1-4 and 11 exhibited strong to weak cytotoxicities against three human tumor cell lines Hela, HCT116 and A549.


Asunto(s)
Antineoplásicos/farmacología , Éteres Fenílicos/farmacología , Xylariales/química , Células A549 , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HCT116 , Células HeLa , Humanos , Estructura Molecular , Éteres Fenílicos/química , Éteres Fenílicos/aislamiento & purificación , Sinomenium/microbiología , Relación Estructura-Actividad
15.
Ultrason Sonochem ; 33: 1-9, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27245950

RESUMEN

The effects of Cl(-) on the corroded surface layer of 00Cr22Ni5Mo3N duplex stainless steel under cavitation in chloride solutions were investigated using nanoindentation in conjunction with XRD and XPS. The results demonstrate that Cl(-) had a strong effect on the nano-mechanical properties of the corroded surface layer under cavitation, and there was a threshold Cl(-) concentration. Furthermore, a close relationship between the nano-mechanical properties and the cavitation corrosion resistance of 00Cr22Ni5Mo3N duplex stainless steel was observed. The degradation of the nano-mechanical properties of the corroded surface layer was accelerated by the synergistic effect between cavitation erosion and corrosion. A key factor was the adsorption of Cl(-), which caused a preferential dissolution of the ferrous oxides in the passive film layer on the corroded surface layer. Cavitation further promoted the preferential dissolution of the ferrous oxides in the passive film layer. Simultaneously, cavitation accelerated the erosion of the ferrite in the corroded surface layer, resulting in the degradation of the nano-mechanical properties of the corroded surface layer on 00Cr22Ni5Mo3N duplex stainless steel under cavitation.

16.
J Vet Sci ; 17(2): 145-52, 2016 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-26243608

RESUMEN

Previous studies have established a bovine mammary gland epithelia cells in vitro model by the adenovirus-mediated telomerase (hTERT-bMGEs). The present study was conducted to confirm whether hTERT-bMGEs were effective target cells to improve the efficiency of transgenic expression and somatic cell nuclear transfer (SCNT). To accomplish this, a mammary-specific vector encoding human lysozyme and green fluorescent protein was used to verify the transgenic efficiency of hTERT-bMGEs, and untreated bovine mammary gland epithelial cells (bMGEs) were used as a control group. The results showed that the hTERT-bMGEs group had much higher transgenic efficiency and protein expression than the bMGEs group. Furthermore, the nontransgenic and transgenic hTERT-bMGEs were used as donor cells to evaluate the efficiency of SCNT. There were no significant differences in rates of cleavage or blastocysts or hatched blastocysts of cloned embryos from nontransgenic hTERT-bMGEs at passage 18 and 28 groups (82.8% vs. 81.9%, 28.6% vs. 24.8%, 58.6% vs. 55.3%, respectively) and the transgenic group (80.8%, 26.5% and 53.4%); however, they were significantly higher than the bMGEs group (71.2%, 12.8% and 14.8%), (p < 0.05). We confirmed that hTERT-bMGEs could serve as effective target cells for improving development of somatic cell cloned cattle embryos.


Asunto(s)
Expresión Génica , Glándulas Mamarias Animales/metabolismo , Muramidasa/genética , Técnicas de Transferencia Nuclear/veterinaria , Telomerasa/biosíntesis , Adenoviridae/genética , Animales , Animales Modificados Genéticamente/genética , Animales Modificados Genéticamente/metabolismo , Bovinos , Clonación de Organismos/veterinaria , Desarrollo Embrionario , Femenino , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Glándulas Mamarias Animales/citología , Muramidasa/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Telomerasa/genética , Transfección/veterinaria
17.
Acta Pharmacol Sin ; 36(11): 1377-87, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26190499

RESUMEN

AIM: To investigate whether the transfer of the IL-37b gene, a newly identified inhibitor of both innate and adaptive immunity, could improve the therapeutic efficacy of mesenchumal stromal cells (MSCs) in inflammatory bowel disease (IBD). METHODS: The expression of IL-37 in biopsied specimens of the patients with active ulcerative colitis (UC) was detected using RT-PCR and immunohistochemistry. Mice were treated with 3% dextran sulfate sodium (DSS) for 8 days to induce colitis. Before DSS treatment, the mice were injected with MSCs, MSC-eGFP or MSC-IL37b. Their body weight was measured each day, and the colons and spleens were harvested on d 10 for pathological and biochemical analyses. RESULTS: In biopsied specimens of the patients with active UC, the expression of IL-37 was dramatically elevated in inflamed mucosa, mainly in epithelial cells and infiltrating immune cells. Compared to MSC-eGFP or MSCs, MSC-IL37b administration significantly attenuated the body weight and colon length reduction, and decreased the histological score in DSS-induced colitis mice. Furthermore, MSC-IL37b administration increased the percentage of myeloid-derived suppressor cells (MDSCs) among total splenic mononuclear cells as well as the percentage of regulatory T cells (Tregs) among splenic CD4+ T cells in the mice. Moreover, MSC-IL37b administration increased the IL-2+ cells and decreased the IFN-γ+ cells among splenic CD4+ T cells. CONCLUSION: IL-37 is involved in the pathophysiology of UC. IL-37b gene transfer enhances the therapeutic efficacy of MSCs in DSS-induced colitis mice by inducing Tregs and MDSCs and regulating cytokine production.


Asunto(s)
Técnicas de Transferencia de Gen , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/terapia , Interleucina-1/genética , Trasplante de Células Madre Mesenquimatosas , Animales , Citocinas/análisis , Sulfato de Dextran , Modelos Animales de Enfermedad , Femenino , Terapia Genética , Humanos , Enfermedades Inflamatorias del Intestino/inducido químicamente , Enfermedades Inflamatorias del Intestino/patología , Trasplante de Células Madre Mesenquimatosas/métodos , Ratones , Ratones Endogámicos C57BL
18.
Acta Pharmacol Sin ; 36(4): 528-34, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25832432

RESUMEN

AIM: IL-37b has shown anti-cancer activities in addition to its anti-inflammatory properties. In this study, we investigated the effects of IL-37b on breast carcinoma growth in mice and to determine the involvement of T cell activation in the effects. METHODS: IL-37b gene was transferred into mouse breast carcinoma cell line 4T1 (4T1-IL37b cells), the expression of secretory IL-37b by the cells was detected, and the effects of IL-37b expression on the cell proliferation in vitro was evaluated. After injection of 4T1 cells or 4T1-IL37b cells into immunocompetent BALB/c mice, immunodeficient BALB/c nude mice and NOD-SCID mice, the tumor growth and survival rate were measured. The proliferation of T cells in vitro was also detected. RESULTS: IL-37b was detected in the supernatants of 4T1-IL37b cells with a concentration of 12.02 ± 0.875 ng/mL. IL-37b expression did not affect 4T1 cell proliferation in vitro. BALB/c mice inoculated with 4T1-IL37b cells showed significant retardation of tumor growth. BALB/c mice inoculated with both 4T1 cells and mitomycin C-treated 4T1-IL37b cells also showed significant retardation of tumor growth. But the anti-cancer activity of IL-37b was abrogated in BALB/c nude mice and NOD-SCID mice inoculated with 4T1-IL37b cells. Recombinant IL-37b slightly promoted CD4(+) T cell proliferation without affecting CD8(+) T cell proliferation. CONCLUSION: IL-37b exerts anti-4T1 breast carcinoma effects in vivo by modulating the tumor microenvironment and influencing T cell activation.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/terapia , Mama/patología , Interleucina-1/genética , Interleucina-1/uso terapéutico , Animales , Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular , Femenino , Técnicas de Transferencia de Gen , Terapia Genética , Células HEK293 , Humanos , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Ratones Desnudos , Ratones SCID , Proteínas Recombinantes/genética , Proteínas Recombinantes/uso terapéutico , Linfocitos T/citología , Linfocitos T/patología
19.
Asian Pac J Cancer Prev ; 14(8): 4501-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24083692

RESUMEN

Caveolin-1 is a scaffold protein on the cell membrane. As the main component of caveolae, caveolin-1 is involved in many biological processes that include substance uptake and transmembrane signaling. Many of these processes and thus caveolin-1 contribute to cell transformation, tumorigenesis, and metastasis. Of particular interest are the dual rolesof tumor suppressor and oncogene that caveolin-1 appear to play in different malignancies, including pancreatic cancer. Therefore, analyzing caveolin-1 regulators and understanding their mechanisms of actionis key to identifying novel diagnostic and therapeutic tools for pancreatic cancer. This review details the mechanisms of action of caveolin-1 regulators and the potential significance for pancreatic cancer treatment.


Asunto(s)
Caveolina 1/metabolismo , Transformación Celular Neoplásica , Regulación Neoplásica de la Expresión Génica , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia , Animales , Humanos , Neoplasias Pancreáticas/metabolismo
20.
World J Gastroenterol ; 18(8): 855-60, 2012 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-22371647

RESUMEN

AIM: To investigate the copy number variation of NACO3 gene in colorectal cancer (CRC) and its correlation with tumor progression. METHODS: A total of 142 samples of case-matched CRC tissues and adjacent normal tissues were obtained from patients undergoing bowel resection. Quantitative real-time polymerase chain reaction method was used to investigate the copy number variations of NCOA3 as well as gene expression in the collected tissues. RESULTS: Copy number gains of NCOA3 were detected in 39 CRC samples (27.5%) and were correlated with tumor progression (χ2 = 6.42, P = 0.0112). Moreover, there was a positive correlation between copy number gain and mRNA over-expression of NCOA3 in CRCs (P = 0.0023). Expression level of NCOA3 mRNA was also enhanced in the CRC samples with unaltered copy numbers (3.85 ± 1.23 vs. 2.71 ± 0.64, P < 0.01). CONCLUSION: Sporadic colorectal cancers exhibit different mechanisms of NCOA3 regulation.


Asunto(s)
Pueblo Asiatico/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Variaciones en el Número de Copia de ADN , Amplificación de Genes , Coactivador 3 de Receptor Nuclear/genética , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Humanos
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