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1.
Small ; 20(9): e2306970, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37867215

RESUMEN

Precise morphology design and electronic structure regulation are critically significant to promote catalytic activity and stability for electrochemical hydrogen production at high current density. Herein, the carbon nanotube (CNT) encapsulated Fe-doped NiCoP nanoparticles is in-situ grown in hierarchical carbonized wood (NCF0.5 P@CNT/CW) for water splitting. Coupling merits of porous carbonized wood (CW) substrate, CNT encapsulating and Fe doping, the NCF0.5 P@CNT/CW features remarkable and durable electrocatalytic activity. The overpotentials of NCF0.5 P@CNT/CW at 50 mA cm-2 mV and 205 mV for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) and features high current density of 800 mA cm-2 within 300 mV for both OER and HER. Moreover, NCF0.5 P@CNT/CW displays outstanding overall water splitting performance (η50 = 1.62 V and η100 = 1.67 V), outperforming Pt/C║RuO2 (η50 = 1.74 V), and can achieve the current density of 700 mA cm-2 at a lower cell voltage of 1.78 V. Overpotential is only 4.0 % decay after 120 h measurement at 50 mA cm-2 . Density functional theory (DFT) calculations reveals Fe doping optimizes the binding energy and Gibbs free energy of intermediates, and regulates d-band center of NCF0.5 P@CNT/CW. Such synergistic strategy of morphology manipulation and electronic structure optimization provides a spark for developing effective and robust bifunctional catalysts.

2.
Small ; 20(25): e2310839, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38225689

RESUMEN

Adhesive materials have played an essential role in the history of humanity. Natural adhesives composed of low-molecular-weight monomers have been overshadowed by modern petroleum-based glues. With the development of green economy, the demand for eco-friendly materials has increased. Herein, two natural biocompatible compounds, namely thioctic acid (TA) and malic acid (MA), are selected to prepare a high-performance pressure-sensitive adhesive poly[TA-MA]. This adhesive can be quantitatively obtained via a simple mixing and heating process. Poly[TA-MA] shows interesting and useful properties, including reversible flexibility, high elongation, and good self-healing, owing to its dynamic polymerization pattern and reversible cross-linking behavior. Poly[TA-MA] exhibits excellent adhesion performance under various extreme conditions, such as at low temperatures and in hot water. High values of shear strength (3.86 MPa), peel strength (7.90 N cm-1), loop tack (10.60 N cm-1), tensile strength (1.02 MPa), and shear resistance (1628 h) demonstrate the strong adhesive effect of poly[TA-MA]. Additionally, TA can be regenerated in the monomer forms from poly[TA-MA] with high recovery rate (>90%). Meanwhile, strong anti-bacterial behavior of poly[TA-MA] is recorded. This study not only reported a new pressure-sensitive adhesive but also fully displayed the feasibility of using natural small molecules to achieve robust surface adhesion.

3.
Physiol Plant ; 176(4): e14422, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38962815

RESUMEN

Low temperatures pose a common challenge in the production of cucumbers and tomatoes, hindering plant growth and, in severe cases, leading to plant death. In our investigation, we observed a substantial improvement in the growth of cucumber and tomato seedlings through the application of corn steep liquor (CSL), myo-inositol (MI), and their combinations. When subjected to low-temperature stress, these treatments resulted in heightened levels of photosynthetic pigments, thereby fostering enhanced photosynthesis in both tomato and cucumber plants. Furthermore, it contributed to a decrease in malondialdehyde (MDA) levels and electrolyte leakage (REP). The effectiveness of the treatment was further validated through the analysis of key gene expressions (CBF1, COR, MIOX4, and MIPS1) in cucumber. Particularly, noteworthy positive outcomes were noted in the treatment involving 0.6 mL L-1 CSL combined with 72 mg L-1 MI. This study provides valuable technical insights into leveraging the synergistic effects of inositol and maize leachate to promote early crop growth and bolster resistance to low temperatures.


Asunto(s)
Frío , Cucumis sativus , Inositol , Plantones , Solanum lycopersicum , Zea mays , Inositol/metabolismo , Zea mays/crecimiento & desarrollo , Zea mays/metabolismo , Zea mays/genética , Zea mays/fisiología , Plantones/crecimiento & desarrollo , Plantones/genética , Solanum lycopersicum/crecimiento & desarrollo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiología , Cucumis sativus/crecimiento & desarrollo , Cucumis sativus/metabolismo , Cucumis sativus/genética , Cucumis sativus/fisiología , Fotosíntesis/efectos de los fármacos , Malondialdehído/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos
4.
Sensors (Basel) ; 24(4)2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38400456

RESUMEN

Distributed optical fibre sensing (DOFS)-based strain measurement systems are now routinely deployed across infrastructure health monitoring applications. However, there are still practical performance and measurement issues associated with the fibre's attachment method, particularly with thermoplastic pipeline materials (e.g., high-density polyethylene, HDPE) and adhesive affixment methods. In this paper, we introduce a new optical fibre installation method that utilises a hot-weld encapsulation approach that fully embeds the fibre onto the pipeline's plastic surface. We describe the development, application and benefits of the new embedment approach (as compared to adhesive methods) and illustrate its practical performance via a full-scale, real-world, dynamic loading trial undertaken on a 1.8 m diameter, 6.4 m long stormwater pipeline structure constructed from composite spiral-wound, steel-reinforced, HDPE pipe. The optical frequency domain reflectometry (OFDR)-based strain results show how the new method improves strain transference and dynamic measurement performance and how the data can be easily interpreted, in a practical context, without the need for complex strain transfer functions. Through the different performance tests, based on UK rail-road network transport loading conditions, we also show how centimetre- to metre-scale strain variations can be clearly resolved at the frequencies and levels consistent with transport- and construction-based, buried infrastructure loading scenarios.

5.
Molecules ; 29(5)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38474450

RESUMEN

The construction of networks within natural wood (NW) lumens to produce porous wood aerogels (WAs) with fascinating characteristics of being lightweight, flexible, and porous is significant for the high value-added utilization of wood. Nonetheless, how wood species affect the structure and properties of WAs has not been comprehensively investigated. Herein, typical softwood of fir and hardwoods of poplar and balsa are employed to fabricate WAs with abundant nanofibrillar networks using the method of lignin removal and nanofibril's in situ regeneration. Benefiting from the avoidance of xylem ray restriction and the exposure of the cellulose framework, hardwood has a stronger tendency to form nanofibrillar networks compared to softwood. Specifically, a larger and more evenly distributed network structure is displayed in the lumens of balsa WAs (WA-3) with a low density (59 kg m-3), a high porosity (96%), and high compressive properties (strain = 40%; maximum stress = 0.42 MPa; height retention = 100%) because of the unique structure and properties of WA-3. Comparatively, the specific surface area (SSA) exhibits 25-, 27-, and 34-fold increments in the cases of fir WAs (WA-1), poplar WAs (WA-2), and WA-3. The formation of nanofibrillar networks depends on the low-density and thin cell walls of hardwood. This work offers a foundation for investigating the formation mechanisms of nanonetworks and for expanding the potential applications of WAs.

6.
Microb Pathog ; 181: 106217, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37385569

RESUMEN

BACKGROUND: In China, the recommended treatment regimens for HIV-infected individuals were tenofovir in combination with lamivudine or emtricitabine as NRTIs, efavirenz or rilpivirine as NNRTIs, lopinavir/ritonavir as protease inhibitors, and raltegravir or dolutegravir as INSTIs. The development of drug resistance increases the risk of viral rebound, opportunistic infections, and ultimately treatment failure such that the early detection of resistance is ideal. This study was developed to explore primary drug resistance characteristics and genotypic distributions in newly diagnosed antiretroviral therapy (ART)-naïve HIV-1 patients in Nanjing with the goal of establishing a basis for their individualized treatment in the clinic. METHODS: Samples of serum were collected from newly diagnosed ART-naïve HIV patients from the Second Hospital of Nanjing between May 2021 and May 2022. The HIV-1 integrase (IN), protease (PR), and reverse transcriptase (RT) gene coding sequences were amplified from these samples, sequenced, and assessed for drug resistance-related mutations. RESULTS: Major integrase resistance-related mutations were detected in 4/360 amplified samples, with 5 other patient samples exhibiting accessory resistance mutations. The overall prevalence of PR and RT inhibitor-related transmitted drug resistance mutations (TDRMs) in this patient population was 16.99% (61/359). The most common mutations were non-nucleoside reverse transcriptase inhibitor-related mutations (51/359; 14.21%), followed by those associated with nucleoside reverse transcriptase inhibitors (7/359; 1.95%) and protease inhibitors (7/359; 1.95%). Dual-resistant strains were also observed in a subset of patients. CONCLUSIONS: In summary, this study is the first to have surveyed the prevalence of integrase inhibitor resistance-related mutations and other drug resistance-related mutations among newly diagnosed ART-naïve HIV-positive patients in Nanjing, China. These results highlight the need for further molecular surveillance-based monitoring of the HIV epidemic in Nanjing.


Asunto(s)
Infecciones por VIH , Humanos , Infecciones por VIH/tratamiento farmacológico , Inhibidores de Integrasa/uso terapéutico , Tenofovir , Inhibidores de Proteasas , Mutación , Farmacorresistencia Viral/genética
7.
Chemistry ; 29(44): e202301277, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37259672

RESUMEN

Switchable self-adhesive films are promising coating materials for constructing smart windows. Compared to commonly used hydrogels, self-adhesive supramolecular films have a variety of advantages and serve as a universal carrier of stimuli-responsiveness. In this study, supramolecular adhesive material is processed into self-adhesive films, which display tough and long-term stable adhesion to commercially available organic/inorganic glass windows. Spiropyrans are used as the photo-responsive units to endow smart windows with switchable optical behavior. Reverse photochromism is successfully realized by the combination of supramolecular films and spiropyrans. Reversible and rapid transformations in the color and transmittance of smart windows are fully achieved by natural light irradiation in different weather conditions, including sun, rain, and clouds.

8.
Plant Cell Rep ; 42(7): 1251-1254, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37052713

RESUMEN

KEY MESSAGE: We explored the phylogenomics and methylomics of NLR genes in 41 plant species and found that highly duplicated plant NLR genes are hyper methylated in non-CG context.


Asunto(s)
Metilación de ADN , Resistencia a la Enfermedad , Metilación de ADN/genética , Resistencia a la Enfermedad/genética , Genes de Plantas/genética
9.
Ann Hepatol ; 28(3): 101086, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36889674

RESUMEN

INTRODUCTION AND OBJECTIVES: Cirrhotic patients with acute variceal hemorrhage (AVH) have high short-term mortality. Established prognostic scores are seldom applicable clinically, partially because they need external validation or contain subjective variables. We aimed to develop and validate a practical prognostic nomogram based on objective predictors to predict prognosis for cirrhotic patients with AVH. PATIENTS AND METHODS: We enrolled 308 AVH patients with cirrhosis from our center as the derivation cohort to develop a new nomogram using logistic regression and validated it in cohorts of patients from Medical Information Mart for Intensive Care (MIMIC) III (n = 247) and IV (n = 302). RESULTS: International normalized ratio (INR), albumin (ALB) and estimated glomerular filtration rate (eGFR) were identified as predictors for inpatient mortality and a nomogram was constructed based on them. The nomogram discriminated well in both derivation and MIMIC-III/-IV validation cohorts with the area under the receiver operating characteristic curves (AUROCs) of 0.846 and 0.859/0.833, respectively and showed a better agreement between expected and observed outcomes (Hosmer-Lemeshow tests, all comparisons, P > 0.05) than other scores in all cohorts. Our nomogram had the lowest Brier scores (0.082/0.114/0.119 in training/MIMIC-III/MIMIC-IV) and highest R2 (0.367/0.393/0.346 in training/MIMIC-III/MIMIC-IV) compared to the recalibrated model for end-stage liver disease (MELD), MELD-hepatic encephalopathy (MELD-HE) and cirrhosis acute gastrointestinal bleeding (CAGIB) scores in all cohorts. CONCLUSIONS: We developed a practical prognostic nomogram using easily verified indicators available in initial patient evaluation, which may serve as a reliable tool to accurately predict inpatient mortality for cirrhotic patients with AVH.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Várices Esofágicas y Gástricas , Humanos , Pronóstico , Nomogramas , Pacientes Internos , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/complicaciones , Enfermedad Hepática en Estado Terminal/complicaciones , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Índice de Severidad de la Enfermedad , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Estudios Retrospectivos
10.
BMC Pediatr ; 23(1): 640, 2023 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-38110898

RESUMEN

BACKGROUND: Compared with a lower neutrophil to lymphocyte ratio(NLR), a higher one denotes severe asthma exacerbation in hospitalized asthmatic children. In addition, NLR is significantly higher in pediatric patients with community-acquired pneumonia (CAP) than those without. Nevertheless, its role in pediatric patients with concomitant asthmatic exacerbation and CAP remains unknown. METHODS: In this retrospective study including 1032 pediatric patients aged 5 to 14 years old, the diagnostic and prognostic value of NLR in children with concomitant asthmatic exacerbation and non-severe CAP were investigated. RESULTS: The sensitivity and specificity of NLR for a diagnosis of CAP in patients with asthmatic exacerbation were 56.9% and 90.1%, respectively. The cutoff value of NLR for a diagnosis of CAP in patients with asthmatic exacerbation was 4.15 (P < 0.001). The cumulative asthmatic exacerbation during 3-month followup of patients with high NLR were 23 (21.3%) and 58 (42.0%) in the asthma and asthmatic CAP groups, respectively (P < 0.001). The patients with high NLR who had unimproved CAP were 15 (8.3%) and 23 (12.2%) in the CAP and asthmatic CAP groups, respectively (P = 0.006). Multivariate analyses showed that along with the increase of NLR by 1.0 point, the HR for the occurrence of asthmatic exacerbation and unimproved CAP were 2.91 [1.83-3.96] (P = 0.001) and 3.38 [1.66-5.10] (P < 0.001), respectively. CONCLUSIONS: NLR had high and moderate diagnostic value for the exclusion and indication of CAP, respectively, in pediatric patients with asthmatic exacerbation. It also had prognostic value for the outcomes of pediatric patients with concomitant asthmatic exacerbation and CAP.


Asunto(s)
Asma , Infecciones Comunitarias Adquiridas , Neumonía , Humanos , Niño , Preescolar , Adolescente , Neutrófilos , Estudios Retrospectivos , Linfocitos , Neumonía/diagnóstico , Asma/complicaciones , Asma/diagnóstico , Pronóstico , Infecciones Comunitarias Adquiridas/diagnóstico
11.
Appl Environ Microbiol ; 87(4)2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33277272

RESUMEN

Glutaredoxins (Grx) are redoxin family proteins that reduce disulfides and mixed disulfides between glutathione and proteins. Rhizobium leguminosarum bv. Viciae 3841 contains three genes coding for glutaredoxins: RL4289 (grxA) codes for a dithiolic glutaredoxin, RL2615 (grxB) codes for a monothiol glutaredoxin, while RL4261 (grxC) codes for a glutaredoxin-like NrdH protein. We generated mutants interrupted in one, two, or three glutaredoxin genes. These mutants had no obvious differences in growth phenotypes from the wild type RL3841. However, while a mutant of grxC did not affect the antioxidant or symbiotic capacities of R. leguminosarum, grxA-derived or grxB mutants decreased antioxidant and nitrogen fixation capacities. Furthermore, grxA mutants were severely impaired in rhizosphere colonization, and formed smaller nodules with defects of bacteroid differentiation, whereas nodules induced by grxB mutants contained abnormally thick cortices and prematurely senescent bacteroids. The grx triple mutant had the greatest defect in antioxidant and symbiotic capacities of R. leguminosarum and quantitative proteomics revealed it had 56 up-regulated and 81 down-regulated proteins relative to wildtype. Of these proteins, twenty-eight are involved in transporter activity, twenty are related to stress response and virulence, and sixteen are involved in amino acid metabolism. Overall, R. leguminosarum glutaredoxins behave as antioxidant proteins mediating root nodule symbiosis.IMPORTANCE Glutaredoxin catalyzes glutathionylation/deglutathionylation reactions, protects SH-groups from oxidation and restores functionally active thiols. Three glutaredoxins exist in R. leguminosarum and their properties were investigated in free-living bacteria and during nitrogen-fixing symbiosis. All the glutaredoxins were necessary for oxidative stress defense. Dithiol GrxA affects nodulation and nitrogen fixation of bacteroids by altering deglutathionylation reactions, monothiol GrxB is involved in symbiotic nitrogen fixation by regulating Fe-S cluster biogenesis, and GrxC may participate in symbiosis by an unknown mechanism. Proteome analysis provides clues to explain the differences between the grx triple mutant and wild-type nodules.

12.
BMC Microbiol ; 21(1): 245, 2021 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-34511061

RESUMEN

BACKGROUND: Bacterial abortive infection (Abi) systems are type IV toxin-antitoxin (TA) system, which could elicit programmed cell death and constitute a native survival strategy of pathogenic bacteria under various stress conditions. However, no rhizobial AbiE family TA system has been reported so far. Here, a M. huakuii AbiE TA system was identified and characterized. RESULTS: A mutation in M. huakuii abiEi gene, encoding an adjacent GntR-type transcriptional regulator, was generated by homologous recombination. The abiEi mutant strain grew less well in rich TY medium, and displayed increased antioxidative capacity and enhanced gentamicin resistance, indicating the abiEi operon was negatively regulated by the antitoxin AbiEi in response to the oxidative stress and a particular antibiotic. The mRNA expression of abiEi gene was significantly up-regulated during Astragalus sinicus nodule development. The abiEi mutant was severely impaired in its competitive ability in rhizosphere colonization, and was defective in nodulation with 97% reduction in nitrogen-fixing capacity. The mutant infected nodule cells contained vacuolation and a small number of abnormal bacteroids with senescence character. RNA-seq experiment revealed it had 5 up-regulated and 111 down-regulated genes relative to wild type. Of these down-regulated genes, 21 are related to symbiosis nitrogen fixation and nitrogen mechanism, 16 are involved in the electron transport chain and antioxidant responses, and 12 belong to type VI secretion system (T6SS). CONCLUSIONS: M. huakuii AbiEi behaves as a key transcriptional regulator mediating root nodule symbiosis.


Asunto(s)
Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica/genética , Mesorhizobium/genética , Nodulación de la Raíz de la Planta , Estrés Fisiológico/genética , Factores de Transcripción/genética , Planta del Astrágalo/microbiología , Proteínas Bacterianas/metabolismo , Estrés Oxidativo , Factores de Transcripción/metabolismo
13.
Nutr Cancer ; 73(2): 215-220, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32336142

RESUMEN

Background: Preoperative assessment of patients is meaningful to predict survival in patients with malignant tumors. The prognostic nutritional index (PNI) is one of the most significant factors related to the prognosis in various types of cancer; however, its role in esophageal cancer is still inconclusive. The aim of this study was to identify the prognostic value of PNI in predicting overall survival (OS) in esophageal squamous cell carcinoma (ESCC).Methods: This retrospective study included 4146 ESCC patients, 3812 who underwent esophagectomy for ESCC. Other 334 had no surgery. The Preoperative PNI was measured before any therapies and calculated as 10 × serum albumin (g/dL) + 0.005 × total lymphocyte count (per mm3). We classified the patients into three categories according to the PNI, >50, 45-50, and <45.Results: Our study showed that PNI was associated with age (P<0.0001), gender(P<0.001),tumor length (P<0.0001), T grade (P = 0.001), N staging (P = 0.017),and M staging (P<0.0001). Multivariate analysis showed that PNI was a significant predictor of overall survival Lower PNI vs. Higher PNI group had significantly increased the hazard ratio of ESCC survival (OR = 1.2, 95% CI= 1.05-1.5, p = 0.01). The Kaplan-Meier curve suggested that high PNI group will significantly increase the OS in both surgical and non-surgical group.Conclusion: PNI is a useful predictive factor for long-term survival in ESCC. The survival rate of ESCC can be discriminated between three groups, PNI, >50, 45-50, and <45. The prognostic value of PNI can be applied for both surgical and non-surgical ESCC patients.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasias de Cabeza y Cuello , Neoplasias Esofágicas/cirugía , Carcinoma de Células Escamosas de Esófago/cirugía , Humanos , Evaluación Nutricional , Estado Nutricional , Pronóstico , Estudios Retrospectivos
14.
J Stroke Cerebrovasc Dis ; 30(10): 106045, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34418671

RESUMEN

BACKGROUND: Matrix metalloproteinase 10 (MMP-10) has a close relationship with carotid atherosclerosis (CAS) and cerebral infarction. The MMP-10 rs17435959 polymorphism causes a leucine to valine transition at codon 4 in exon 1 of the MMP-10 gene and may have functional effects. OBJECTIVES: To investigate the relationship between the MMP-10 rs17435959 polymorphism and the formation and stability of CAS plaques. MATERIALS AND METHODS: The present case-control study contains 738 visitors who came to our health examination center for the first time. According to the carotid ultrasound examinations, visitors were classified into the vulnerable plaque group (41-86 years old, 141 male, 105 female), the stable plaque group (41-86 years old, 141 male, 105 female) and the no plaque group (41-85 years old, 141 male, 105 female). All visitors in the three groups were sex- and- age-matched, and cardiovascular and cerebrovascular diseases were absent. The polymorphism was genotyped by real-time polymerase chain reaction- restriction. RESULTS: Compared to the GG genotype, the frequency of the CC and CG genotypes was significantly more common in the vulnerable plaque group than in the no plaque group (18.7% vs. 7.7%, unadjusted P = 0.002). Moreover, compared to the G allele, the frequency of the C allele was significantly more common in the vulnerable plaque group than in the no plaque group (10.4% vs. 3.9%, unadjusted P = 0.000) and in the vulnerable plaque group than in the stable plaque group (10.4% vs. 5.1%, unadjusted P = 0.008). Binary logistic regression showed that the CC and CG genotype was independent risk factor for the formation (P = 0.019, OR = 1.961, 95% CI [1.117, 3.444]) and vulnerability (P = 0.035, OR = 1.842, 95% CI [1.045, 3.247]) of CAS plaques. Moreover, individuals who have the C allele showed a higher level of fibrinogen, which was an independent risk factor for the formation of CAS plaques (P = 0.000, OR = 2.425, 95% CI [1.475, 3.985]). CONCLUSIONS: The rs17435959 polymorphism was associated with the formation and vulnerability of CAS plaques. Individuals who had variant-type MMP-10 showed higher levels of fibrinogen, which promoted the formation of CAS plaques.


Asunto(s)
Enfermedades de las Arterias Carótidas/genética , Metaloproteinasa 10 de la Matriz/genética , Placa Aterosclerótica , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/enzimología , Estudios de Casos y Controles , Femenino , Fibrinógeno/análisis , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Pronóstico , Medición de Riesgo , Factores de Riesgo , Rotura Espontánea
15.
Microb Cell Fact ; 19(1): 195, 2020 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-33069248

RESUMEN

BACKGROUND: A new Bacillus thuringiensis X023 (BtX023) with high insecticidal activity was isolated in Hunan Province, China. The addition of metals (Cu, Fe, Mg and Mn) to the medium could influence the formation of spores and/or insecticidal crystal proteins (ICPs). In previous studies, Cu ions considerably increased the synthesis of ICPs by enhancing the synthesis of poly-ß-hydroxy butyrate. However, the present study could provide new insights into the function of Cu ions in ICPs. RESULTS: Bioassay results showed that wild strain BtX023 exhibited high insecticidal activity against Plutella xylostella. The addition of 1 × 10-5 M Cu2+ could considerably increase the expression of cry1Ac and vip3Aa, and the insecticidal activity was enhanced. Quantitative real-time polymerase chain reaction (qRT-PCR) and proteomic analyses revealed that the upregulated proteins included amino acid synthesis, the glyoxylate pathway, oxidative phosphorylation, and poly-ß-hydroxy butyrate synthesis. The Cu ions enhanced energy metabolism and primary amino acid synthesis, will providing abundant raw material accumulation for ICP synthesis. CONCLUSION: The new strain BtX023 exerted a strong insecticidal effect on P. xylostella by producing ICPs. The addition of 1 × 10-5 M Cu2+ in the medium could considerably enhance the expression of the cry1Ac and vip3Aa genes, thereby further increasing the toxicity of BtX023 to Helicoverpa armigera and P. xylostella by enhancing energy synthesis, the glyoxylate cycle, and branched-chain amino acids synthesis, but not poly-ß-hydroxy butyrate synthesis.


Asunto(s)
Bacillus thuringiensis , Proteínas Bacterianas/metabolismo , Cationes/farmacología , Cobre/farmacología , Insecticidas , Mariposas Nocturnas/efectos de los fármacos , Animales , Bioensayo , China , Medios de Cultivo/química , Metabolismo Energético , Larva/efectos de los fármacos , Proteómica
16.
Curr Microbiol ; 77(1): 1-10, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31624868

RESUMEN

Legumes interact with symbiotic rhizobia to produce nitrogen-fixation root nodules under nitrogen-limiting conditions. The contribution of glutathione (GSH) to this symbiosis and anti-oxidative damage was investigated using the M. huakuii gshB (encoding GSH synthetase) mutant. The gshB mutant grew poorly with different monosaccharides, including glucose, sucrose, fructose, maltose, or mannitol, as sole sources of carbon. The antioxidative capacity of gshB mutant was significantly decreased by these treatments with H2O2 under the lower concentrations and cumene hydroperoxide (CUOOH) under the higher concentrations, indicating that GSH plays different roles in response to organic peroxide and inorganic peroxide. The gshB mutant strain displayed no difference in catalase activity, but significantly lower levels of the peroxidase activity and the glutathione reductase activity than the wild type. The same level of catalase activity could be associated with upregulation of the transcriptional activity of the catalase genes under H2O2-induced conditions. The nodules infected by the gshB mutant were severely impaired in abnormal nodules, and showed a nodulation phenotype coupled to a 60% reduction in the nitrogen fixation capacity. A 20-fold decrease in the expression of two nitrogenase genes, nifH and nifD, is observed in the nodules induced by gshB mutant strain. The symbiotic deficiencies were linked to bacteroid early senescence.


Asunto(s)
Glutatión/metabolismo , Nódulos de las Raíces de las Plantas/metabolismo , Acetileno/metabolismo , Derivados del Benceno/farmacología , Fabaceae/efectos de los fármacos , Fabaceae/genética , Fabaceae/metabolismo , Glutatión Reductasa/genética , Glutatión Reductasa/metabolismo , Peróxido de Hidrógeno/farmacología , Mesorhizobium/metabolismo , Simbiosis/fisiología
17.
Fish Physiol Biochem ; 46(5): 1699-1711, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32621163

RESUMEN

The Nrf2 (nuclear factor erythroid 2-related factor 2) plays a central role in cell protection against a wide variety of environmental stressors through the Nrf2-Keap1 (Kelch-like ECH-associated protein 1) pathway, but its involvement in modulation of antioxidant system of fish cell is still largely unexplored. The present study focused on the molecular cloning and silencing of the Nrf2 in the fathead minnow muscle cell line (FHM) in response to the oxidative stress induced by H2O2. A full-length cDNA of coding Nrf2 was cloned from FHM cells by RT-PCR and RACE approaches. The obtained cDNA covered 2578 bp with an open reading frame (1770 bp) of encoding 589 amino acids. Sequence alignment and phylogenetic analysis revealed a high degree of conservation (51-86%) among 16 fishes. Based on the cloned Nrf2 sequence, the siRNA-242 of targeting Nrf2 with the best knocking down efficiency was designed and detected. Then, the mRNA levels of Keap1, Nrf2, Maf (musculoaponeurotic fibrosarcoma oncogene), and HO-1 (haemoxygenase-1); the activities of T-SOD (total superoxide dismutase), CAT (catalase), and GSH-PX (glutathione peroxidase); the levels of GSH (glutathione) and MDA (malonaldehyde); and the cell cycle and apoptosis were analyzed to investigate the molecular responses after H2O2 exposure. These results showed a coordinated transcriptional regulation of Keap1, Maf, and HO-1 and antioxidants (T-SOD, GSH, CAT, and GSH-PX) and MDA levels after H2O2 exposure, leading to oxidative damage and apoptosis. These findings provided an insight to understand the mechanisms of Nrf2 against oxidative stress in fish.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Peróxido de Hidrógeno/farmacología , Músculo Esquelético/citología , Factor 2 Relacionado con NF-E2/metabolismo , Salmonidae , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Regulación de la Expresión Génica/efectos de los fármacos , Silenciador del Gen , Factor 2 Relacionado con NF-E2/genética , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Filogenia
18.
J Gene Med ; 21(5): e3086, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30861607

RESUMEN

BACKGROUND: Overexpression of the murine double minute 2 (MDM2) has been explored in many tumors with high proliferation and anti-apoptosis ability. However, the role of MDM2 and its functional single nucleotide polymorphism (SNP) rs2279744 (also known as SNP309) in esophageal squamous cell carcinoma (ESCC) remains unclear. METHODS: We performed a genotype study of blood samples in 360 ESCC patients and 360 healthy control individuals to determine the risk of various rs2279744 in ESCC. To further evaluate the role of rs2279744 in regulating MDM2 expression, we performed an allele-specific reporter assay and investigated whether the SNP-containing sequences functioned as an active enhancer. To examine the functional role of MDM2 on esophageal cancer cell lines, we carried out an MTS assay and flow cytometry analysis. RESULTS: From the genotyping study, we found that GG genotype of SNP309 significantly increased the risk of ESCC in an additive model [odds ratio (OR) = 2.55, 95% confidence interval (CI) = 1.66-3.89, p = 1.50 × 10-5 ) and in a recessive model (OR = 2.44, 95% CI = 1.69-3.51, p = 1.60 × 10-8 ). Furthermore, the G allele was significantly associated with a higher risk of ESCC (OR = 1.56, 95% CI = 1.26-1.92, p = 2.81 × 10-5 ). In multivariate logistic regression analysis, the GG genotype had increased the occurrence of ESCC by 2.39-fold (95% CI = 1.48-3.8). Compared to the T allele, the variant G allele had significantly higher luciferase activity on the promoter of MDM2 in both cell lines. By transfecting the gene to ESCC lines, we showed that overexpression of MDM2 significantly promote cell proliferation and anti-apoptosis. CONCLUSIONS: The MDM2 promoter SNP309 is a risk factor for esophageal cancer. MDM2 promotes the proliferation and anti-apoptosis of ESCC.


Asunto(s)
Alelos , Neoplasias Esofágicas/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas c-mdm2/genética , Adulto , Anciano , Apoptosis/genética , Estudios de Casos y Controles , Línea Celular Tumoral , Neoplasias Esofágicas/diagnóstico , Carcinoma de Células Escamosas de Esófago/diagnóstico , Carcinoma de Células Escamosas de Esófago/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Frecuencia de los Genes , Genes Reporteros , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Regiones Promotoras Genéticas
19.
J Bone Miner Metab ; 37(6): 976-986, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31214838

RESUMEN

Several cellular and molecular processes participate in the pathologic changes of osteoarthritis (OA). However, the core molecular regulators of these processes are unclear, and no effective treatment for OA disease has been developed so far. ANGPTL2 is well known for its tissue remolding and pro-inflammation properties. However, the role of ANGPTL2 in osteoarthritis (OA) still remains unclear. To explore the expression level of ANGPTL2 in human OA cartilage and investigate the function of ANGPTL2 in human chondrocytes injury, qRT-PCR, western blot and immunohistochemistry were employed to investigate the expression of ANGPTL2 between human OA and normal cartilage samples. Next, human primary chondrocytes were treated with IL-1ß to mimic OA progress in vitro, and the expression of ANGPTL2 were tested by qRT-PCR and western blot. Furthermore, the effect of ANGPTL2 in the expression of pro-inflammation cytokines (IL-1ß, IL-6), proteolytic enzymes (MMP-1, MMP-13) and component of the cartilage matrix (COL2A1 and aggrecan) in human primary chondrocyte were explored by gain-of-function and loss-of-function methods. Finally, the nuclear factor kappa B (NF-κB) and p38/MAPK signaling pathways were also tested by western blot analysis. In this study, firstly, the expression level of ANGPTL2 was elevated both in human OA cartilage samples and IL-1ß stimulated human chondrocytes. Secondly, ANGPTL2 upregulation promotes extracellular matrix (ECM) degradation and inflammation mediator production in human chondrocytes. Finally, ANGPTL2 activated the NF-κB and p38/MAPK signaling pathways via integrin α5ß1. This study, for the first time, highlights that ANGPTL2 secreted by human chondrocytes plays a negative role in the pathogenesis of osteoarthritis, and it may be a potential therapeutic target in OA.


Asunto(s)
Proteínas Similares a la Angiopoyetina/genética , Condrocitos/metabolismo , Condrocitos/patología , Interleucina-1beta/farmacología , Sistema de Señalización de MAP Quinasas , FN-kappa B/metabolismo , Regulación hacia Arriba/genética , Proteína 2 Similar a la Angiopoyetina , Proteínas Similares a la Angiopoyetina/metabolismo , Cartílago/efectos de los fármacos , Cartílago/metabolismo , Cartílago/patología , Células Cultivadas , Condrocitos/efectos de los fármacos , Colágeno Tipo II/metabolismo , Humanos , Integrina alfa5beta1/metabolismo , Interleucina-6/biosíntesis , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Metaloproteinasas de la Matriz/metabolismo , Osteoartritis/metabolismo , Osteoartritis/patología , Regulación hacia Arriba/efectos de los fármacos
20.
Ecotoxicol Environ Saf ; 172: 97-104, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30684757

RESUMEN

Endophyte-assisted phytoremediation has gained increasing attention. However, the interacting mechanisms of endophytes and metal hyperaccumulators are still not clear. An endophytic bacterium Pseudomonas fluorescens Sasm05 inoculation promoted Sedum alfredii Hance rooting and root development, in which the specific root length (SRL) and average number of root tips (ART) increased to 2.09- and 3.35-fold, respectively. Sasm05 inoculation promoted plant growth, increased the chlorophyll content, and elevated Zn uptake of plant at excess Zn supply. At 200 µM Zn treatment level, Sasm05 inoculation increased plant biomass and the chlorophyll content by more than 40%, and root Zn content by 40%. Furthermore, Sasm05 inoculation upregulated the expression of the Zn transporter SaIRT1 to 3.43-fold in the roots, while another transporter SaNramp1 expression was increased to 38.66-fold in the roots and 7.53-fold in the shoots. Time course study showed the best effects of Sasm05 on plant biomass and the chlorophyll content were detected at 30 d, while for Zn content at 3 d. These results firstly provided molecular evidences of endophytic bacteria in facilitating host plant Zn uptake, which will absolutely benefit the understanding of interacting mechanisms between hyperaccumulators and their endophytes.


Asunto(s)
Bacterias/metabolismo , Raíces de Plantas/microbiología , Sedum/microbiología , Zinc/metabolismo , Biodegradación Ambiental , Transporte Biológico , Biomasa , Clorofila/análisis , Endófitos/metabolismo , Regulación de la Expresión Génica de las Plantas , Desarrollo de la Planta , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Sedum/metabolismo , Contaminantes del Suelo/análisis
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