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1.
Small ; : e2402819, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837885

RESUMO

Janus-micromotors, as efficient self-propelled materials, have garnered considerable attention for their potential applications in non-agitated liquids. However, the design of micromotors is still challenging and with limited approaches, especially concerning speed and mobility in complex environments. Herein, a two-step spray-drying approach encompassing symmetrical assembly and asymmetrical assembly is introduced to fabricate the metal-organic framework (MOF) Janus-micromotors with hierarchical pores. Using a spray-dryer, a symmetrical assembly is first employed to prepare macro-meso-microporous UiO-66 with intrinsic micropores (<0.5 nm) alongside mesopores (≈24 nm) and macropores (≈400 nm). Subsequent asymmetrical assembly yielded the UiO-66-Janus loaded with the reducible nanoparticles, which underwent oxidation by KMnO4 to form MnO2 micromotors. The micromotors efficiently generated O2 for self-propulsion in H2O2, exhibiting ultrahigh speeds (1135 µm s-1, in a 5% H2O2 solution) and unique anti-gravity diffusion effects. In a specially designed simulated sand-water system, the micromotors traversed from the lower water to the upper water through the sand layer. In particular, the as-prepared micromotors demonstrated optimal efficiency in pollutant removal, with an adsorption kinetic coefficient exceeding five times that of the micromotors only possessing micropores and mesopores. This novel strategy fabricating Janus-micromotors shows great potential for efficient treatment in complex environments.

2.
Sensors (Basel) ; 24(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38676086

RESUMO

This paper presents the design and the non-linearity optimization of a new vertical non-contact angle sensor based on the electromagnetic induction principle. The proposed sensor consists of a stator part (with one solenoidal excitation coil and three sinusoidal receiver coils) and a rotor part (with six rectangular metal sheets). The receiver coil was designed based on the differential principle, which eliminates the effect of the excitation coil on the induced voltage of the receiver coil, and essentially decouples the excitation field from the eddy current field. Moreover, the induced voltages in the three receiver coils are three-phase sinusoidal signals with a phase difference of 10°, which are linearized by CLARK transformation. To minimize the sensor non-linearity, the Plackett-Burman technique was used, which identified the stator radius and the rotor blade thickness as the key factors affecting the sensor linearity. Then, the particle swarm algorithm with decreasing inertia weights was utilized to optimize the sensor linearity. A sensor prototype was made and tested in the laboratory, where the experimental results showed that the sensor non-linearity was only 0.648% and 0.645% in the clockwise and counterclockwise directions, respectively. Notably, the non-linearity of the sensor was less than -0.696% at different speeds.

3.
J Environ Manage ; 351: 119745, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061094

RESUMO

Applying biochar to soil has been recognized as a promising practice of climate-smart agriculture, with considerable potential in enhancing soil organic carbon (SOC) sequestration. Previous studies showed that biochar-induced increases in SOC stock varied substantially among experiments, while the explanatory factors responsible for such variability are still not well assessed. Here, we conducted an integrative meta-analysis of the magnitude and efficiency of biochar-induced change in SOC stock, using a database including 476 field measurements at 101 sites across the globe. Biochar amendment increased SOC stock by 6.13 ± 1.62 (95% confidence interval, CI) and 7.01 ± 1.11 (95% CI) Mg C ha-1, respectively, compared to their unfertilized (R0) and mineral nitrogen (N) fertilized (Rn) references. Of which approx. 52% (R0) and 50% (Rn) were contributed directly by biochar-C input. Corresponding biochar carbon efficiencies in R0 and Rn datasets were estimated as 58.20 ± 10.37% and 65.58 ± 9.26% (95% CI), respectively. The change magnitude of SOC stock increased significantly (p < 0.01) with the increasing amount of biochar-C input, while carbon efficiency of biochar showed an opposite trend. Biochar amendment sequestered larger amounts of SOC with higher efficiency in acidic and loamy soils than in alkaline and sandy soils. Biochar amendments with higher C/N ratio caused higher SOC increase than those with lower C/N ratio. Random forest (RF) algorithm showed that accumulative biochar-C input, soil pH, and biochar C/N ratio were the three most-important factors regulating the SOC stock responses. Overall, these results suggest that applying high C/N ratio biochar in acidic soils is a recommendable agricultural practice from the perspective of enhancing organic carbon.


Assuntos
Carbono , Solo , Carvão Vegetal , Agricultura/métodos , Sequestro de Carbono
4.
BMC Plant Biol ; 23(1): 470, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803280

RESUMO

BACKGROUND: Genomic imprinting refers to a subset of genes that are expressed from only one parental allele during seed development in plants. Studies on genomic imprinting have revealed that intraspecific variations in genomic imprinting expression exist in naturally genetic varieties. However, there have been few studies on the functional analysis of allele-specific imprinted genes. RESULTS: Here, we generated three reciprocal crosses among the B73, Mo17 and CAU5 inbred lines. Based on the transcriptome-wide analysis of allele-specific expression using RNA sequencing technology, 305 allele-specific imprinting genes (ASIGs) were identified in embryos, and 655 ASIGs were identified in endosperms from three maize F1 hybrids. Of these ASIGs, most did not show consistent maternal or paternal bias between the same tissue from different hybrids or different tissues from one hybrid cross. By gene ontology (GO) analysis, five and eight categories of GO exhibited significantly higher functional enrichments for ASIGs identified in embryo and endosperm, respectively. These functional categories indicated that ASIGs are involved in intercellular nutrient transport, signaling pathways, and transcriptional regulation of kernel development. Finally, the mutation and overexpression of one ASIG (Zm305) affected the length and width of the kernel. CONCLUSION: In this study, our data will be helpful in gaining further knowledge of genes exhibiting allele-specific imprinting patterns in seeds. The gain- and loss-of-function phenotypes of ASIGs associated with agronomically important seed traits provide compelling evidence for ASIGs as crucial targets to optimize seed traits in crop plants.


Assuntos
Endosperma , Transcriptoma , Endosperma/metabolismo , Alelos , Zea mays/metabolismo , Sementes/genética , Impressão Genômica , Regulação da Expressão Gênica de Plantas
5.
Small ; 19(24): e2208212, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36916691

RESUMO

137 Cs and 90 Sr are hazardous to ecological environment and human health due to their strong radioactivity, long half-life, and high mobility. However, effective adsorption and separation of Cs+ and Sr2+ from acidic radioactive wastewater is challenging due to stability issues of material and the strong competition of protons. Herein, a K+ -activated niobium germanate (K-NGH-1) presents efficient Cs+ /Sr2+ coadsorption and highly selective Cs+ /Sr2+ separation, respectively, under different acidity conditions. In neutral solution, K-NGH-1 exhibits ultrafast adsorption kinetics and high adsorption capacity for both Cs+ and Sr2+ (qm Cs  = 182.91 mg g-1 ; qm Sr  = 41.62 mg g-1 ). In 1 M HNO3 solution, K-NGH-1 still possesses qm Cs of 91.40 mg g-1 for Cs+ but almost no adsorption for Sr2+ . Moreover, K-NGH-1 can effectively separate Cs+ from 1 M HNO3 solutions with excess competing Sr2+ and Mn + (Mn +  = Na+ , Ca2+ , Mg2+ ) ions. Thus, efficient separation of Cs+ and Sr2+ is realized under acidic conditions. Besides, K-NGH-1 shows excellent acid and radiation resistance and recyclability. All the merits above endow K-NGH-1 with the first example of niobium germanates for radionuclides remediation. This work highlights the facile pH control approach towards bifunctional ion exchangers for efficient Cs+ /Sr2+ coadsorption and selective separation.

6.
CMAJ ; 195(12): E437-E448, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36972914

RESUMO

BACKGROUND: Accessible measures specific to the Canadian context are needed to support health system planning for older adults living with frailty. We sought to develop and validate the Canadian Institute for Health Information (CIHI) Hospital Frailty Risk Measure (HFRM). METHODS: Using CIHI administrative data, we conducted a retrospective cohort study involving patients aged 65 years and older who were discharged from Canadian hospitals from Apr. 1, 2018, to Mar. 31, 2019. We used a 2-phase approach to develop and validate the CIHI HFRM. The first phase, construction of the measure, was based on the deficit accumulation approach (identification of age-related conditions using a 2-year look-back). The second phase involved refinement into 3 formats (continuous risk score, 8 risk groups and binary risk measure), with assessment of their predictive validity for several frailty-related adverse outcomes using data to 2019/20. We assessed convergent validity with the United Kingdom Hospital Frailty Risk Score. RESULTS: The cohort consisted of 788 701 patients. The CIHI HFRM included 36 deficit categories and 595 diagnosis codes that cover morbidity, function, sensory loss, cognition and mood. The median continuous risk score was 0.111 (interquartile range 0.056-0.194, equivalent to 2-7 deficits); 35.1% (n = 277 000) of the cohort were found at risk of frailty (≥ 6 deficits). The CIHI HFRM showed satisfactory predictive validity and reasonable goodness-of-fit. For the continuous risk score format (unit = 0.1), the hazard ratio (HR) for 1-year risk of death was 1.39 (95% confidence interval [CI] 1.38-1.41), with a C-statistic of 0.717 (95% CI 0.715-0.720); the odds ratio for high users of hospital beds was 1.85 (95% CI 1.82-1.88), with a C-statistic of 0.709 (95% CI 0.704-0.714), and the HR of 90-day admission to long-term care was 1.91 (95% CI 1.88-1.93), with a C-statistic of 0.810 (95% CI 0.808-0.813). Compared with the continuous risk score, using a format of 8 risk groups had similar discriminatory ability and the binary risk measure had slightly weaker performance. INTERPRETATION: The CIHI HFRM is a valid tool showing good discriminatory power for several adverse outcomes. The tool can be used by decision-makers and researchers by providing information on hospital-level prevalence of frailty to support system-level capacity planning for Canada's aging population.


Assuntos
Fragilidade , Humanos , Idoso , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Estudos Retrospectivos , Canadá/epidemiologia , Hospitalização , Fatores de Risco , Hospitais , Idoso Fragilizado , Avaliação Geriátrica
7.
World J Surg Oncol ; 21(1): 339, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37880729

RESUMO

BACKGROUND: To determine the efficacy of adjuvant radiotherapy for stage II-III biliary tract carcinoma. METHODS: We retrospectively analyzed the data of 37 patients who underwent radical resection of biliary tract carcinomas at the Affiliated Hospital of Inner Mongolia Medical University between 2016 and 2020. We analyzed survival differences between patients who did (n = 17) and did not (n = 20) receive postoperative adjuvant radiotherapy by using Kaplan-Meier analysis. The log-rank test and Cox univariate analysis were used. The Cox proportional risk regression model was used for the multifactorial analysis of factors influencing prognosis. RESULTS: The median survival time (28.9 vs. 14.5 months) and the 1-year (82.40% vs. 55.0%) and 2-year survival rates (58.8% vs. 25.0%) were significantly higher among patients who received adjuvant radiotherapy than among those who did not (χ2 = 6.381, p = 0.012). Multifactorial analysis showed that pathological tumor type (p = 0.004), disease stage (p = 0.021), and adjuvant radiotherapy (p = 0.001) were independent prognostic factors in biliary tract carcinoma. Subgroup analyses showed that compared to no radiotherapy, adjuvant radiotherapy significantly improved median survival time in patients with stage III disease (21.6 vs. 12.7 months; p = 0.017), positive margins (28.9 vs. 10.5 months; p = 0.012), and T3 or T4 tumors (26.8 vs. 16.8 months; p = 0.037). CONCLUSION: Adjuvant radiotherapy significantly improved the survival of patients with biliary tract carcinoma, and is recommended especially for patients with stage III disease, positive surgical margins, or ≥ T3.


Assuntos
Sistema Biliar , Carcinoma , Neoplasias Gastrointestinais , Humanos , Radioterapia Adjuvante/efeitos adversos , Estudos Retrospectivos , Prognóstico , Estadiamento de Neoplasias
8.
Molecules ; 28(5)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36903625

RESUMO

Bismuth-halide-based inorganic-organic hybrid materials (Bi-IOHMs) are desirable in luminescence-related applications due to their advantages such as low toxicity and chemical stability. Herein, two Bi-IOHMs of [Bpy][BiCl4(Phen)] (1, Bpy = N-butylpyridinium, Phen = 1,10-phenanthroline) and [PP14][BiCl4(Phen)]·0.25H2O (2, PP14 = N-butyl-N-methylpiperidinium), containing different ionic liquid cations and same anionic units, have been synthesized and characterized. Single-crystal X-ray diffraction reveals that compounds 1 and 2 crystallize in the monoclinic space group of P21/c and P21, respectively. They both possess zero-dimensional ionic structures and exhibit phosphorescence at room temperature upon excitation of UV light (375 nm for 1, 390 nm for 2), with microsecond lifetime (24.13 µs for 1 and 95.37 µs for 2). Hirshfeld surface analysis has been utilized to visually exhibit the different packing motifs and intermolecular interactions in 1 and 2. The variation in ionic liquids makes compound 2 have a more rigid supramolecular structure than 1, resulting in a significant enhancement in photoluminescence quantum yield (PLQY), that is, 0.68% for 1 and 33.24% for 2. In addition, the ratio of the emission intensities for compounds 1 and 2 shows a correlation with temperature. This work provides new insight into luminescence enhancement and temperature sensing applications involving Bi-IOHMs.

9.
Can Pharm J (Ott) ; 156(3): 159-171, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37201168

RESUMO

Background: Data on Canadian pharmacists' knowledge and perceptions about frailty in older adults and its assessment in pharmacy practice are scarce. Methods: A cross-sectional survey of 349 Canadian pharmacists was conducted to evaluate pharmacists' knowledge, perceptions and practices regarding frailty. Descriptive analyses summarized responses by practice setting, and a multivariable logistic regression model examined associations between respondent characteristics and the likelihood of assessing frailty. Results: Most respondents were female (70%), aged ≤34 years (47%), Canadian graduates (83%), from Ontario/Quebec (51%) and from urban centres (58%). Although a significant proportion agreed it is important for pharmacists to know (80%) and assess (56%) patient frailty status, only 36% reported assessing frailty in practice. Respondents exclusively practising in a community pharmacy were significantly less likely to agree that it is important for a pharmacist to know or assess frailty status and to report assessing it. Factors associated with a greater likelihood of assessment included positive beliefs about the importance of knowing a patient's frailty status and having a greater proportion of older patients with cognitive or functional impairment in practice. Discussion: Findings suggest that pharmacists generally agree with the importance of understanding frailty as it relates to the appropriate use of medications, but most do not assess it. Further research is needed to identify the barriers to assessing frailty, while guidance is needed on which of the available screening tools can best be integrated into a clinical pharmacy practice. Conclusion: There is an opportunity to improve pharmaceutical care for older adults by providing pharmacists the means and resources to assess frailty in practice.

10.
Inorg Chem ; 61(49): 20073-20079, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36445334

RESUMO

Designing earth-abundant electrocatalysts that are highly active, low-cost, and stable for the oxygen evolution reaction (OER) is crucial for electrochemical water splitting. However, in conventional electrode fabrication strategies, NiFe layered double hydroxide (NiFe LDH) catalysts are usually coated onto substrates as external components, which suffers from poor conductivity, easily detaches from the substrate, and hinders their long-term utilization. Herein, the surface-reconstruction strategy is used to synthesize in situ autologous NiFe LDH to increase the surficial active sites numbers. The FeNi foam (FNF) serves as both the metal source and substrate, and the obtained NiFe LDH nanosheets (NSs) are firmly anchored in the monolithic FNF. What needs to be emphasized is that the strategy does not involve any high-temperature or high-pressure processes, apart from a cost-effective etching and a specified drying treatment. The nanostructure of NiFe LDH and the synergistic effect between Fe and Ni simultaneously lead to an enhanced catalytic effect for the OER. Remarkably, the sr-FNF46 requires only an ultralow overpotential of 283 mV to achieve a current density of 100 mA cm-2 for the OER in 1 M KOH electrolyte, and exhibits excellent stability. Thus, the obtained electrode holds promise for electrocatalytic applications. Finally, the formation mechanism of NiFe LDH NSs due to surface reconstruction is investigated and discussed in detail.


Assuntos
Nanoestruturas , Oxigênio , Catálise , Eletrodos , Água
11.
Health Rep ; 33(6): 3-16, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35876612

RESUMO

Background: Estimates of polypharmacy have primarily been derived from prescription claims, and less is known about the use of non-prescription medications (alone or in combination with prescription medications) across the frailty spectrum or by sex. Our objectives were to estimate the prevalence of polypharmacy (total, prescription, non-prescription, and concurrent prescription and non-prescription) overall, and by frailty, sex and broad age group. Data: Canadian Health Measures Survey, Cycle 5, 2016 to 2017. Methods: Among Canadians aged 40 to 79 years, all prescription and non-prescription medications used in the month prior to the survey were documented. Polypharmacy was defined as using five or more medications total (prescription and non-prescription), prescription only and non-prescription only. Concurrent prescription and non-prescription use was defined as two or more and three or more of each. Frailty was defined using a 31-item frailty index (FI) and categorized as non-frail (FI ≤ 0.1) and pre-frail or frail (FI > 0.1). Survey-weighted descriptive statistics were calculated overall and age standardized. Results: We analyzed 2,039 respondents, representing 16,638,026 Canadians (mean age of 56.9 years; 51% women). Overall, 52.4% (95% confidence interval [CI] = 47.3 to 57.4) were defined as pre-frail or frail. Age-standardized estimates of total polypharmacy, prescription polypharmacy and concurrent prescription and non-prescription medication use were significantly higher among pre-frail or frail versus non-frail adults (e.g., total polypharmacy: 64.1% versus 31.8%, respectively). Polypharmacy with non-prescription medications was common overall (20.5% [95% CI = 16.1 to 25.8]) and greater among women, but did not differ significantly by frailty. Interpretation: Polypharmacy and concurrent prescription and non-prescription medication use were common among Canadian adults, especially those who were pre-frail or frail. Our findings highlight the importance of considering non-prescribed medications when measuring the exposure to medications and the potential risk for adverse outcomes.


Assuntos
Fragilidade , Idoso , Canadá/epidemiologia , Feminino , Idoso Fragilizado , Fragilidade/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimedicação , Prevalência
12.
Sensors (Basel) ; 22(11)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35684821

RESUMO

In this study, the circular Gaussian spot emitted by a laser light source is shaped into a rectangular flat-top beam to improve the scanning efficiency of a selective laser sintering scanning system. A CO2 laser with a power of 200 W, wavelength of 10.6 µm, and spot diameter of 9 mm is shaped into a flat-top spot with a length and width of 0.5 × 0.1 mm, and the mapping function and flat-top Lorentzian function are calculated. We utilize ZEMAX to optimize the aspherical cylindrical lens of the shaping system and the cylindrical lens of the focusing system. We then calculate the energy uniformity of the flat-top line-shaped beam at distances from 500 to 535 mm and study the zoom displacement of the focusing lens system. The results indicated that the energy uniformity of the flat-top beam was greater than 80% at the distances considered, and the focusing system must precisely control the displacement of the cylindrical lens in the Y-direction to achieve precise zooming.

13.
Cell Mol Biol (Noisy-le-grand) ; 66(2): 87-92, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415932

RESUMO

Cerebral infarction is an acute cerebrovascular disease caused by abnormal blood circulation in the brain. In the present study, we investigate the effect of astragaloside IV on cognitive dysfunction in cerebrally infarcted rats via transforming growth factor-ß (TGF-ß) / Smad signaling pathway. For this purpose, 45 rats were divided into three groups including astragaloside, model, and control. 30 of 45 healthy adult male SD rats were randomly selected to establish an acute cerebral infarction model. 15 modeled rats were enrolled as a model and astragaloside group, and another 15 rats as a blank control group. The rats in the astragaloside group were fed with astragaloside IV according to 1.08 g/kg body weight, and those in the blank group and model group were given matching normal saline. The levels of TGF-ß, Smad1, Smad3 and Smad7 of TGF-ß/Smad signaling transduction pathway at T0 (week 0), T1 (week 3) and T2 (week 6) were determined by enzyme-linked immunosorbent assay (ELISA). The modified neurological severity score (mNSS) was used to evaluate the improvement of cognitive dysfunction in rats. The mNSS of rats with cerebral infarction in the astragaloside group was lower than that in the control group and model group (P< 0.05). While the levels of TGF-ß, Smad1, Smad3 and Smad7 in the astragaloside group were higher than those in the control group and model group (P< 0.05). Astragaloside IV plays an important role in improving cognitive dysfunction in rats with cerebral infarction while affecting the levels of TGF-ß, Smad1, Smad3 and Smad7 and activating TGF-ß / Smad signaling pathway.


Assuntos
Infarto Cerebral/tratamento farmacológico , Saponinas/uso terapêutico , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Triterpenos/uso terapêutico , Animais , Estudos de Casos e Controles , Infarto Cerebral/patologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Masculino , Ratos , Ratos Sprague-Dawley , Saponinas/farmacologia , Índice de Gravidade de Doença , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/análise , Proteína Smad1/análise , Proteína Smad3/análise , Proteína Smad7/análise , Triterpenos/farmacologia
14.
Sensors (Basel) ; 19(6)2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30875816

RESUMO

This paper is focused on designing a cost function of selecting a foothold for a physical quadruped robot walking on rough terrain. The quadruped robot is modeled with Denavit⁻Hartenberg (DH) parameters, and then a default foothold is defined based on the model. Time of Flight (TOF) camera is used to perceive terrain information and construct a 2.5D elevation map, on which the terrain features are detected. The cost function is defined as the weighted sum of several elements including terrain features and some features on the relative pose between the default foothold and other candidates. It is nearly impossible to hand-code the weight vector of the function, so the weights are learned using Supporting Vector Machine (SVM) techniques, and the training data set is generated from the 2.5D elevation map of a real terrain under the guidance of experts. Four candidate footholds around the default foothold are randomly sampled, and the expert gives the order of such four candidates by rotating and scaling the view for seeing clearly. Lastly, the learned cost function is used to select a suitable foothold and drive the quadruped robot to walk autonomously across the rough terrain with wooden steps. Comparing to the approach with the original standard static gait, the proposed cost function shows better performance.

15.
Toxicol Appl Pharmacol ; 344: 35-45, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29496522

RESUMO

Ulcerative colitis (UC) is a chronic and relapsing inflammatory disorder of the colon and rectum with increasing morbidity in recent years. 15,16-dihydrotanshinone Ӏ (DHT) is a natural product with multiple bioactivities. In this study, we aimed to investigate the protective effect and potential mechanisms of DHT on UC. Dextran sulfate sodium salt (DSS) was administrated in drinking water for 7 days to induce UC in mice. DHT (10 and 25 mg/kg) significantly alleviated DSS-induced body weight loss, disease activity index (DAI) scores, and improved histological alterations of colon tissues. DHT inhibited the myeloperoxidase (MPO) activity, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in colon tissues and decreased serum levels of TNF-α, IL-1ß, IL-6, and high-mobility group box 1 (HMGB1). Furthermore, increased expression of kinases receptor-interacting protein 1 (RIP1), RIP3, mixed lineage kinase domain-like protein (MLKL) and decreased expression of caspase-8 in colon tissues were partially restored by DHT. In LPS-stimulated RAW264.7 macrophages, DHT significantly inhibited generation of nitric oxide, IL-6, TNF-α and protein expression of iNOS, COX-2. In addition, increased expression of iNOS, COX-2, and phosphorylated RIP1, RIP3, MLKL in response to LPS plus Z-VAD (LZ) were also suppressed by DHT. DHT had no effect on TNF-α + BV6 + Z-VAD (TBZ) induced phosphorylation of RIPs and MLKL in HT29 cells. Especially, DHT showed no effect on LZ and TBZ-induced necroptosis in RAW264.7 and HT29 cells, respectively. In summary, DHT alleviated DSS-induced UC in mice by suppressing pro-inflammatory mediators and regulating RIPs-MLKL-caspase-8 axis.


Assuntos
Abietanos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Produtos Biológicos/uso terapêutico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Sulfato de Dextrana/toxicidade , Animais , Colite Ulcerativa/patologia , Relação Dose-Resposta a Droga , Células HT29 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7
16.
New Phytol ; 215(4): 1503-1515, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28722229

RESUMO

A major resistance quantitative trait locus, qRfg1, significantly enhances maize resistance to Gibberella stalk rot, a devastating disease caused by Fusarium graminearum. However, the underlying molecular mechanism remains unknown. We adopted a map-based cloning approach to identify the resistance gene at qRfg1 and examined the dynamic epigenetic changes during qRfg1-mediated maize resistance to the disease. A CCT domain-containing gene, ZmCCT, is the causal gene at the qRfg1 locus and a polymorphic CACTA-like transposable element (TE1) c. 2.4 kb upstream of ZmCCT is the genetic determinant of allelic variation. The non-TE1 ZmCCT allele is in a poised state, with predictive bivalent chromatin enriched for both repressive (H3K27me3/H3K9me3) and active (H3K4me3) histone marks. Upon pathogen challenge, this non-TE1 ZmCCT allele was promptly induced by a rapid yet transient reduction in H3K27me3/H3K9me3 and a progressive decrease in H3K4me3, leading to disease resistance. However, TE1 insertion in ZmCCT caused selective depletion of H3K4me3 and enrichment of methylated GC to suppress the pathogen-induced ZmCCT expression, resulting in disease susceptibility. Moreover, ZmCCT-mediated resistance to Gibberella stalk rot is not affected by photoperiod sensitivity. This chromatin-based regulatory mechanism enables ZmCCT to be more precise and timely in defense against F. graminearum infection.


Assuntos
Elementos de DNA Transponíveis/genética , Resistência à Doença/genética , Epigênese Genética , Gibberella/fisiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Zea mays/genética , Zea mays/microbiologia , Alelos , Metilação de DNA/genética , Regulação da Expressão Gênica de Plantas , Histonas/metabolismo , Fotoperíodo , Mapeamento Físico do Cromossomo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Locos de Características Quantitativas/genética , Plântula/genética
17.
BMC Infect Dis ; 17(1): 210, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28298186

RESUMO

BACKGROUND: Mannose-binding lectin (MBL) is an important protein in the lectin pathway of the immune system. This study explores the association between MBL polymorphism and the susceptibility to tuberculosis (TB). The association between the MBL2 polymorphisms and serum MBL levels is also analyzed in the present study. METHODS: A total of 112 inpatients with pulmonary TB and 120 healthy controls were recruited to participate in this case-control study. Polymerase Chain Reaction-Restriction Fragment Length Polymorphism(PCR-RFLP) technology was used to genotype MBL gene (variants in -221Y/X and exon l codons 54 A/B). Serum MBL level was assayed by human MBL ELISA kit. Demographic data and exposure information were also obtained from the study participants. RESULTS: Genotypes YA/YA of MBL gene were more prevalent in the healthy control group than in the TB patient (P =0.038, OR, 0.57; 95% CI, 0.34-0.97) and genotypes XA/XA were less frequent in the healthy control group (P =0.007, OR, 6.42; 95% CI, 1.39-29.67). The resistant diplotype was more frequently found in the younger patients and retreatment cases with TB in MBL gene sites -221Y/X or codon 54 A/B. X/Y and A/B polymorphisms were strong determinants of serum MBL levels. CONCLUSION: The polymorphisms of MBL gene may be associated with susceptibility to TB and the recurrence of TB. The YA/YA may be a protected diplotype against TB.


Assuntos
Predisposição Genética para Doença/genética , Lectina de Ligação a Manose/genética , Polimorfismo Genético , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , China/epidemiologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/fisiopatologia , Adulto Jovem
18.
Sensors (Basel) ; 17(11)2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29117140

RESUMO

The fact that piezoelectric ceramic transducer (PZT) precision drive systems in 3D printing are faced with nonlinear problems with respect to positioning, such as hysteresis and creep, has had an extremely negative impact on the precision of laser focusing systems. To eliminate the impact of PZT nonlinearity during precision drive movement, mathematical modeling and theoretical analyses of each module comprising the system were carried out in this study, a micro-displacement measurement circuit based on Position Sensitive Detector (PSD) is constructed, followed by the establishment of system closed-loop control and creep control models. An XL-80 laser interferometer (Renishaw, Wotton-under-Edge, UK) was used to measure the performance of the precision drive system, showing that system modeling and control algorithms were correct, with the requirements for precision positioning of the drive system satisfied.

19.
BMC Genomics ; 17: 477, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27352627

RESUMO

BACKGROUND: Gibberella stalk rot caused by Fusarium graminearum is one of the most destructive soil-borne diseases of maize (Zea mays L.). Chemical means of controlling Gibberella stalk rot are not very effective; development of highly resistant hybrids is the best choice for disease control. Hence, understanding of the molecular basis underlying maize resistance against Gibberella stalk rot would undoubtedly facilitate the resistance breeding for stalk rot. RESULTS: Two quantitative trait loci (QTL), qRfg1 and qRfg2, conferring resistance to Gibberella stalk rot were detected in our previous study. Three near-isogenic lines (NILs) of maize with either qRfg1 (NIL1) or qRfg2 (NIL2), or neither (NIL3) were generated and subjected to RNA sequencing to study the transcriptional changes after F. graminearum inoculation at 0 (control), 6, and 18 h post-inoculation (hpi). In total, 536,184,652 clean reads were generated, and gene expression levels were calculated using FPKM (fragments per kilobase of exon model per million mapped reads). A total of 7252 differentially expressed genes (DEGs) were found in the three NILs after F. graminearum inoculation. As many as 2499 DEGs were detected between NIL1 and NIL3 at 0 hpi, of which 884 DEGs were more abundant in NIL1 and enriched in defense responses. After F. graminearum inoculation, 1070 and 751 genes were exclusively up- and downregulated, respectively, in NIL1 as compared to NIL3. The 1070 upregulated DEGs were enriched in growth/development, photosynthesis/biogenesis, and defense-related responses. Genes encoding putative auxin-induced proteins and GH3 family proteins in auxin signaling pathway were highly induced and lasted longer in NIL3. Genes involved in polar auxin transport (PAT) were more abundant in NIL3 as compared with NIL2. CONCLUSIONS: The qRfg1 confers its resistance to Gibberella stalk rot through both constitutive and induced high expression of defense-related genes; while qRfg2 enhances maize resistance to the disease via relatively lower induction of auxin signaling and repression of PAT. The defense-related transcriptional changes underlying each QTL will undoubtedly facilitate our understanding of the resistance mechanism and resistance breeding for maize stalk rot.


Assuntos
Resistência à Doença/genética , Fusarium/fisiologia , Perfilação da Expressão Gênica , Doenças das Plantas/microbiologia , Zea mays/genética , Zea mays/microbiologia , Genes de Plantas/genética , Fenótipo , Análise de Sequência de RNA , Zea mays/imunologia
20.
Langmuir ; 32(46): 12047-12055, 2016 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-27788584

RESUMO

Water-Cu(110) interaction is of particular importance during the routine use of graphene-based devices. In this work, water adsorption, dissociation, and desorption at elevated temperatures have been well studied using the time-of-flight ion scattering technique. It is found that water adsorption meets the first-order Langmuir adsorption model at room temperature. The variation of the ratio between residual O and H on the surface with temperature has been well determined, which profoundly reveals the dynamical process of surface composition. Furthermore, the change in the surface electronic properties has been probed by measuring negative-ion fractions as a function of the annealing temperature for fast ion scattering. It suggests that charge transfer is a very sensitive method for studying specific electronic processes in real time.

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