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The Tibetan Plateau, housing 20% of China's wetlands, plays a vital role in the regional carbon cycle. Examining the phenological dynamics of wetland vegetation in response to climate change is crucial for understanding its impact on the ecosystem. Despite this importance, the specific effects of climate change on wetland vegetation phenology in this region remain uncertain. In this study, we investigated the influence of climate change on the end of the growing season (EOS) of marsh wetland vegetation across the Tibetan Plateau, utilizing satellite-derived Normalized Difference Vegetation Index (NDVI) data and observational climate data. We observed that the regionally averaged EOS of marsh vegetation across the Tibetan Plateau was significantly (p < .05) delayed by 4.10 days/decade from 2001 to 2020. Warming preseason temperatures were found to be the primary driver behind the delay in the EOS of marsh vegetation, whereas preseason cumulative precipitation showed no significant impact. Interestingly, the responses of EOS to climate change varied spatially across the plateau, indicating a regulatory role for hydrological conditions in marsh phenology. In the humid and cold central regions, preseason daytime warming significantly delayed the EOS. However, areas with lower soil moisture exhibited a weaker or reversed delay effect, suggesting complex interplays between temperature, soil moisture, and EOS. Notably, in the arid southwestern regions of the plateau, increased preseason rainfall directly delayed the EOS, while higher daytime temperatures advanced it. Our results emphasize the critical role of hydrological conditions, specifically soil moisture, in shaping marsh EOS responses in different regions. Our findings underscore the need to incorporate hydrological factors into terrestrial ecosystem models, particularly in cold and dry regions, for accurate predictions of marsh vegetation phenological responses to climate change. This understanding is vital for informed conservation and management strategies in the face of current and future climate challenges.
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Ecosistema , Humedales , Tibet , Desarrollo de la Planta , Estaciones del Año , Cambio Climático , Agua , Temperatura , SueloRESUMEN
For designing conductive polymer composites (CPCs), understanding how the fiber curvature affects the percolation behavior of curved conductive fibers is essential for determining the effective electrical conductivity σeff of the CPCs. In this work, CPCs were considered as a polymer matrix filled with the random packing of overlapped curved spherocylinders. The geometries of the curved spherocylinders were defined, and inter-curved spherocylinder contact-detecting and system-spanning fiber cluster searching algorithms were developed. The finite-size-scaling method was used to explore how the aspect ratio α and bending central angle θ of a curved spherocylinder affect the percolation threshold Ïc of an overlapped curved spherocylinder system in 3D space. The findings suggest that Ïc decreases as α increases and increases initially before declining as θ increases. An empirical approximation formula was proposed to quantify the effect of the curved spherocylinder's morphology, characterized by the dimensionless excluded volume Vdex of the curved spherocylinder, on Ïc. The new rigorous bound for Ïc of the soft-curved spherocylinder system was further proposed. A random resistor network model was constructed, and the reliability of this model was validated by comparing the simulations and published data. Finally, a fitting formula was developed to assess the impacts of the normalized reduced density (η - ηc)/ηc and Vdex on the σeff of CPCs. A distinct linear correlation between σeff and (η - ηc)/ηc was constructed, denoted as σeff â¼ [(η - ηc)/ηc]t(α,θ). An empirical approximation model was proposed to establish the relationship between the fiber shape and conductivity exponent t. Our study may provide a theoretical hint for the design of CPCs.
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INTRODUCTION: Hyperglycaemia induces the production of a large quantity of reactive oxygen species (ROS) and activates the transforming growth factor ß1 (TGF-ß1)/Smad signalling pathway, which is the main initiating factor in the formation of diabetic nephropathy. Indoxyl sulphate (IS) is a protein-binding gut-derived uraemic toxin that localizes to podocytes, induces oxidative stress, and inflames podocytes. The involvement of podocyte damage in diabetic nephropathy through the TGF-ß1 signalling pathway is still unclear. METHODS: In this study, we cultured differentiated rat podocytes in vitro and measured the expression levels of nephrin, synaptopodin, CD2AP, SRGAP2a, and α-SMA by quantitative real-time PCR (qRT-PCR) and Western blotting after siRNA-mediated TGF-ß1 silencing, TGF-ß1 overexpression, and the presence of the ROS inhibitor acetylcysteine. We detected the expression levels of nephrin, synaptopodin, CD2AP, SRGAP2a, small mother against decapentaplegic (Smad)2/3, phosphorylated-Smad2/3 (p-Smad2/3), Smad7, NADPH oxidase 4 (NOX4), and ROS levels under high glucose (HG) and IS conditions. RESULTS: The results indicated that nephrin, synaptopodin, CD2AP, and SRGAP2a expressions were significantly upregulated, and α-SMA expression was significantly downregulated in the presence of HG under siRNA-mediated TGF-ß1 silencing or after the addition of acetylcysteine. However, in the presence of HG, the expressions of nephrin, synaptopodin, CD2AP, and SRGAP2a were significantly downregulated, and the expression of α-SMA was significantly upregulated with the overexpression of TGF-ß1. IS supplementation under HG conditions further significantly reduced the expressions of nephrin, synaptopodin, CD2AP, and SRGAP2a; altered the expressions of Smad2/3, p-Smad2/3, Smad7, and NOX4; and increased ROS production in podocytes. CONCLUSION: This study suggests that IS may modulate the expression of nephrin, synaptopodin, CD2AP, and SRGAP2a by regulating the ROS and TGF-ß1/Smad signalling pathways, providing new theoretical support for the treatment of diabetic nephropathy.
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Nefropatías Diabéticas , Indicán , Podocitos , Especies Reactivas de Oxígeno , Transducción de Señal , Factor de Crecimiento Transformador beta1 , Indicán/toxicidad , Indicán/farmacología , Podocitos/metabolismo , Podocitos/patología , Animales , Ratas , Especies Reactivas de Oxígeno/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Proteínas Smad/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Proteínas de Microfilamentos/metabolismo , Células Cultivadas , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas del Citoesqueleto/metabolismo , Proteínas del Citoesqueleto/genéticaRESUMEN
The acquisition and processing of skylight polarization information forms the cornerstone in modern navigation systems that are developed by imitating certain biological mechanisms. The accuracy of skylight polarization mode information plays a major part in improving the accuracy of polarized light navigation. This paper mainly focuses on developing a methodology that can avoid the error caused by the inaccurate rotation of the polarizer and manual readings from non-electrical equipment, when the time-sequence polarization measurement system is used to obtain the skylight polarization mode information. We propose an adaptive algorithm that can obtain the pictures of angle of polarization and degree of polarization with sets of random rotation angles with no need for precise readings for the rotation angle of the polarizer. By allocating initial random values to rotation angles, a simple iterative estimation method like the Gaussian-Newton method can be used to converge calculated angle of polarization and degree of polarization values to their respective real values. The experiment results show that the proposed method can be used to estimate polarization information with high accuracy and universality under various experiment settings including both sunny and cloudy weathers. Meanwhile, the time efficiency of the proposed method is comparable to traditional methods.
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Researchers have found that some animals can use the skylight polarization pattern for navigation. It is also expected to use the skylight polarization pattern for human navigating in the near future. However, the challenge is that the need for a more accurate and efficient model of the imaging of skylight polarization is always felt. In this paper, three improved models of imaging of skylight polarization are proposed. The proposed models utilize the analysis of the distribution of the skylight polarization pattern after the polarization imaging system. Given that the skylight polarization pattern after the polarization imaging system is distorted, the focus of this paper is on the degree of distortion of the skylight polarization pattern in these imaging models. Experiments in clear weather conditions demonstrate that the proposed model operates close to the actual acquired skylight polarization pattern.
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BACKGROUND: Despite the restoration of epicardial flow after primary percutaneous coronary intervention (PPCI), myocardial reperfusion remains impaired in a significant proportion of patients. We performed a network meta-analysis to assess the effect of 7 intracoronary agents (adenosine, anisodamine, diltiazem, nicorandil, nitroprusside, urapidil, and verapamil) on the no-reflow phenomenon in patients with ST-elevation myocardial infarction (STEMI) undergoing PPCI. METHODS: Database searches were conducted to identify randomized controlled trials (RCTs) comparing the 7 agents with each other or with standard PPCI. Outcome measures included thrombolysis in myocardial infarction flow grade (TFG), ST-segment resolution (STR), left ventricular ejection fraction (LVEF), major adverse cardiovascular events (MACEs), and adverse events. RESULTS: Forty-one RCTs involving 4069 patients were analyzed. The addition of anisodamine to standard PPCI for STEMI was associated with improved post-procedural TFG, more occurrences of STR, and improvement of LVEF. The cardioprotective effect of anisodamine conferred a MACE-free survival benefit. Additionally, nitroprusside was regarded as efficient in improving coronary flow and clinical outcomes. Compared with standard care, adenosine, nicorandil, and verapamil improved coronary flow but had no corresponding benefits regarding cardiac function and clinical outcomes. The ranking probability for the 7 treatment drugs showed that anisodamine consistently ranked the highest in efficacy outcomes (TFG < 3, STR, LVEF, and MACEs). No severe adverse events, such as hypotension and malignant arrhythmia, were observed in patients treated with anisodamine. Network meta-regression analysis showed that age, the time to reperfusion, and study follow-up did not affect the treatment effects. CONCLUSIONS: The intracoronary administration of anisodamine appears to improve myocardial reperfusion, cardiac function, and clinical outcomes in patients with STEMI undergoing PPCI. Given the limited quality and quantity of the included studies, more rigorous RCTs are needed to verify the role of this inexpensive and well-tolerated regimen.
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Circulación Coronaria/efectos de los fármacos , Fenómeno de no Reflujo/tratamiento farmacológico , Intervención Coronaria Percutánea/efectos adversos , Infarto del Miocardio con Elevación del ST/terapia , Alcaloides Solanáceos/administración & dosificación , Vasodilatadores/uso terapéutico , Anciano , Teorema de Bayes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fenómeno de no Reflujo/diagnóstico , Fenómeno de no Reflujo/etiología , Fenómeno de no Reflujo/fisiopatología , Oportunidad Relativa , Factores de Riesgo , Infarto del Miocardio con Elevación del ST/diagnóstico , Infarto del Miocardio con Elevación del ST/fisiopatología , Alcaloides Solanáceos/efectos adversos , Resultado del Tratamiento , Vasodilatadores/efectos adversosRESUMEN
A novel "Turn-On" fluorescent probe, quaternarized 4-pyridinyl-substituted BODIPY dye by incorporating a 5-nitrofuran moiety, was developed and applied for imaging the hypoxic status of tumor cells by the indirect detection of nitroreductase. The design was based on a nitroreductase-catalyzed reduction of the nitrofuran moiety in the presence of reduced nicotinamide adenine dinucleotide (NADH) as an electron donor and followed by the 1,6-rearrangement-elimination and the release of free 4-pyridinyl-substituted BODIPY dye . This probe displayed desired properties such as high specificity, "Turn-On" fluorescence response with suitable sensitivity, appreciable water solubility and rapid response time (within 5 min). Moreover, as a biocompatible molecule, the probe has been successfully applied for imaging the hypoxic status of tumor cells (e.g. A549 cells) and especially used for real-time determination of nitroreductase produced by Escherichia coli. Therefore, we hope to apply this novel method in the biomedical research fields for the imaging of disease-relevant hypoxia and detection of pathogenic microorganisms.
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Hipoxia de la Célula/fisiología , Neoplasias/metabolismo , Nitrofuranos/metabolismo , Nitrorreductasas/análisis , Compuestos de Boro/química , Línea Celular Tumoral , Diagnóstico por Imagen/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Colorantes Fluorescentes , Humanos , NAD/química , Nitrofuranos/químicaRESUMEN
This study was designed to investigate the impact of ultra-filtration extract mixture from Astragals mongholicus (UEMAM) o radiosensitivity of H22 ascitic tumor in mice to 12C6+ ions radiation. The H22 ascitic tumor model was established in mice by intraperitoneal injection of 0.2 mL H22 ascitic cells. The animals were subsequently divided into 4 groups randomly, treated with normal saline, UEMAM, heavy ion beam radiotherapy and UEMAM plus heavy ion beam radiotherapy, respectively. The body weights, abdomen circumference of the mice were measured and the mouse behavior was monitored every day; survival time was recorded to evaluate life extension effect; flow cytometry technique was used to detect H22 cell apoptosis and cell cycle; protein levels of p53, Bax, Bcl-2 and cleaved Caspase-3 were analyzed by Western blot; the single cell gel electrophoresis was used to detect the level of deoxyribonucleic acid damage (DNA damage). The results suggest that UEMAM significantly increased survival time, and decreased body weights and abdomen circumference over the saline control group. The treatment increased cell apoptosis, cycle arrest and DNA damage compared to the saline control group. UEMAM significantly enhanced the therapeutic effect of heavy ion beam radiation in survival time, and decreased body weights and abdomen circumference in the tumor-baring mice. The combination increased cell apoptosis, cycle arrest and DNA damage compared to the radiotherapy group. The results of Western blot suggest that the treatment significantly enhanced p53-induced apoptotic signals. The experiment discovered that UEMAM could improve radiosensitivity of H22 ascitic tumor through activation of p53-mediated apoptotic signal pathway.
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Planta del Astrágalo/química , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/radioterapia , Extractos Vegetales/farmacología , Tolerancia a Radiación , Animales , Apoptosis , Ciclo Celular , Línea Celular Tumoral , Daño del ADN , Iones , Ratones , Transducción de SeñalRESUMEN
The pyrolysis process of pine wood, a promising biofuel feedstock, has been studied with tunable synchrotron vacuum ultraviolet photoionization mass spectrometry. The mass spectra at different photon energies and temperatures as well as time-dependent profiles of several selected species during pine wood pyrolysis process were measured. Based on the relative contents of three lignin subunits, the data indicate that pine wood is typical of softwood. As pyrolysis temperature increased from 300 to 700 °C, some more details of pyrolysis chemistry were observed, including the decrease of oxygen content in high molecular weight species, the observation of high molecular weight products from cellulose chain and lignin polymer, and potential pyrolysis mechanisms for some key species. The formation of polycyclic aromatic hydrocarbons (PAHs) was also observed, as well as three series of pyrolysis products derived from PAHs with mass difference of 14 amu. The time-dependent profiles show that the earliest products are formed from lignin, followed by hemicellulose products, and then species from cellulose.
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Pinus/química , Madera/química , Celulosa/análisis , Calor , Lignina/análisis , Espectrometría de Masas/instrumentación , Hidrocarburos Policíclicos Aromáticos/análisis , Sincrotrones , Rayos Ultravioleta , VacioRESUMEN
In this study, we assessed the toxic effects of formaldehyde (FA) on mouse bone marrow mesenchymal stem cells (BM-MSCs). Cytotoxicity was measured by using MTT assay. DNA strand breakage was detected by standard alkaline comet assay and comet assay modified with proteinase K (PK). DNA-protein crosslinks (DPCs) were detected by KCl-SDS precipitation assay. We found that FA at a concentration from 75 to 200 µM inhibited cell survival and induced DPCs over 125 µM. The PK-modified comet assay showed that FA-induced DNA strand breakage was increased in a dose-dependent manner from 75 to 200 µM. On the other hand, standard alkaline comet assay showed that DNA strand breakage was decreased with FA concentration over 125 µM. We confirmed by using Pearson correlation that there was a negative linear correlation between DPCs and survival rate (r = -0.987, P < 0.01) and positive linear relationships between DPCs and (i) sister chromatid exchange and (ii) micronucleus (r = 0.995, P < 0.01; r = 0.968, P < 0.01). DNA damage RT(2) profiler polymerase chain reaction array was used to investigate the changes in the expression of damage response genes. Xpa and Xpc of the nucleotide excision repair pathway and Brca2, Rad51, and Xrcc2 of the homologous recombination pathway were all up-regulated in both 75 and 125 µM FA. However, the same genes were down-regulated with 175 µM FA. The expressions of Chek1 and Hus1, which are involved in cell cycle regulation, were altered in the same manner with 75, 125, and 175 µM FA. These results indicated that Xpa, Xpc, Brca2, Rad51, Xrcc2, Chek1, and Hus1 were essential for the BM-MSCs to counteract the effects of FA.
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Daño del ADN/genética , Reparación del ADN/genética , Formaldehído/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Animales , Proteína BRCA2/genética , Proteínas de Ciclo Celular/genética , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Células Cultivadas , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Ensayo Cometa , Roturas del ADN/efectos de los fármacos , Proteínas de Unión al ADN/genética , Relación Dosis-Respuesta a Droga , Células Madre Mesenquimatosas/metabolismo , Ratones , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Pruebas de Micronúcleos , Proteínas Quinasas/genética , Recombinasa Rad51/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Intercambio de Cromátides Hermanas/efectos de los fármacos , Proteína de la Xerodermia Pigmentosa del Grupo A/genéticaRESUMEN
OBJECTIVE: To study the effect of flavonoids from Hedysari Radix on pulmonary functions of pulmonary fibrosis rat and its mechanism. METHODS: 72 Wistar rats were randomly divided into 6 groups: blank control group, model group, prednisone group, Hedysari Radix flavonoids low, medium and high dosage group. The rat model was established by propelling bleomycin into bronchial tree through endotracheal intubation with laryngoscope. The pulmonary fanctions were measured. RESULTS: Hedysari Radix flavonoids could normalize the pulmonary functions of rats with bleomycin-induced pulmonary fibrosis. CONCLUSION: Hedysari Radix flavonoids can inhibit the process of pulmonary fibrosis.
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Fabaceae/química , Flavonoides/farmacología , Rendimiento Pulmonar/efectos de los fármacos , Pulmón/efectos de los fármacos , Fibrosis Pulmonar/tratamiento farmacológico , Animales , Bleomicina/farmacología , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Flavonoides/administración & dosificación , Volumen Espiratorio Forzado/fisiología , Pulmón/fisiopatología , Rendimiento Pulmonar/fisiología , Masculino , Prednisona/administración & dosificación , Prednisona/farmacología , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/fisiopatología , Distribución Aleatoria , Ratas , Ratas WistarRESUMEN
The leaf primordium derives from the peripheral zone of shoot apical meristem. During the formation of leaf primordia, they need to establish the proximodistal, mediolateral, and ab/adaxial axes. Among these axes, the ab/adaxial axis might be the most important. ASYMMETRIC LEAVES2 (AS2) gene is a member of AS2/LATERAL ORGAN BOUNDARY (LOB) family of Arabidopsis thaliana. In this work, we transformed 35S:AS2 transgene constructs to cockscomb (Celosia cristata) via Agrobacterium tumefaciens. All primary transformants subsequently obtained were placed into phenotypic categories and self-pollinated. As a whole, a total of 44 T1 35S:AS2 cockscomb plants obtained were grouped into two major categories: (I) slightly wrinkled leaves (28/44), (II) extremely curved leaves (16/44), on the basis of their leaf phenotypes. Furthermore, we characterized the anatomical features of these malformed leaves; and found the transformation of adaxial cell types into abaxial cell ones. A series of data suggest that AS2 might be involved in the determination of abaxial polarity in cockscomb plants. However, a few research teams have reported that AS2 might be involved in the determination of adaxial polarity in leaf primodia of Arabidopsis thaliana. These data above indicate that the roles of the same ab/adaxial determinant might differ between distinct species. At last, the different function of AS2 in distinct species was discussed.
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Proteínas de Arabidopsis/genética , Arabidopsis/genética , Tipificación del Cuerpo/genética , Celosia/anatomía & histología , Celosia/genética , Genes de Plantas/genética , Hojas de la Planta/anatomía & histología , Factores de Transcripción/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Fenotipo , Hojas de la Planta/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Transcripción/metabolismoRESUMEN
A universal method for modeling and characterizing non-circular particles is developed. The n-point correlation functions (n = 1, 2 and 3) are efficiently computed with a GPU parallel computing procedure. An algorithm for dynamic packing of impenetrable non-circular particles is developed based on the fast estimation of overlap information using a one-point correlation function. The packing algorithm is independent of particle shape and proved to be reliable by examples of polygons and super-ellipses. In addition, penetrable packings are generated in an efficient and precise way. Using a two-point correlation function, these non-circular packs are accurately characterized and compared in terms of features such as penetrable and impenetrable, packing fraction and particle shape. In addition, three-point correlation functions are also illustrated and discussed.
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Estimating the effective properties of a particulate system is the most direct way to understand its macroscopic performance. In this work, we accurately evaluate the third-order approximations involving the three-point microstructural parameter ζ, which can be calculated from a triple integral involving 1-, 2-, and 3-point correlation functions. A GPU-based parallel algorithm was developed for quickly computing the n-point correlation functions, and the results agree well with analytical solutions. The effective thermal conductivity and diffusion coefficient are calculated by the third-order approximates for the random-packing systems of a super-ellipsoid. By changing the parameters of the super-ellipsoid, the particle-shape effect can be predicted for both the thermal conductivity and diffusion coefficient.
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This study's objective is to evaluate the correlation relationship between Podocalyxin (PCX), an urinary marker of podocytes, urinary albumin-creatinine ratio (ACR) and the predictive value of PCX in the routine screen of early diabetic kidney disease (DKD) among older people. We also aimed to explore its prediction value despite of other metabolic factor and how PCX alters in the predictive power for early stage of diabetic nephropathy. In retrospective, 320 cases of older patients diagnosed with type 2 diabetes mellitus who met both inclusion and exclusion criteria were collected and divided with levels of urinary albumin, that is, normal albuminuria group, microalbuminuria group and healthy group. The correlation coefficient between PCX and ACR, and the odds ratio of PCX were gauged in the study. Area under the receiver operating characteristic (ROC) curve was also calculated. There were 188 patients in the normal group with urine ACR<30mg/g, and 132 patients in the microproteinuria group with urine ACR 30-300mg/g. 132 cases of DKD diagnosed with ACR, among them, 104 cases of DKD were predicted by PCX. The percentage correction value was 78.8%. The following parameters such as gender, age, course of disease, glycated hemoglobin, triglyceride, total cholesterol, BMI, blood pressure, uric acid, and eGFR were used as variables for adjustment to establish the prediction model of urine PCX and ACR. Multiple logistic regression test was carried out to evaluate against the predictive ability of the model. The area under the ROC curve corresponding to the regression model after adjustment is 0.952. Although factors such as the course of disease, HbA1C, UA, and eGFR could influence on the predictive ability of PCX, PCX still has a good ability to predict early DKD in older patients. Therefore, it could be used as a diagnostic indicator for early-stage DKD in older patients.
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Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Humanos , Anciano , Creatinina , Diabetes Mellitus Tipo 2/complicaciones , Estudios Retrospectivos , Albuminuria , AlbúminasRESUMEN
The correct use of connectives has great influence on language learners' writing proficiency, while errors of connectives are common in foreign learners' interlanguages. This study examines the types of errors that occur in native English-speaking learners' Chinese writing, the possible causes for the errors, and the learners' consequent learning strategies. The present research adopted corpora investigation, questionnaire survey, and focus-group interviews to examine the error types, causes of identified errors, and related learning strategies. Data analysis indicated that: (1) the main error types made by native English-speaking learners from high to low are misuse, overuse, mismatch, misplacement, and underuse of connectives; (2) causes related to intralingual transfer greatly contributes to the presence of errors; and (3) memory, social, and cognitive strategies were the most preferred, followed by metacognitive and compensation strategies, and then by effective strategies which were the least preferred. These findings showed that different strategies can be employed to cope with different errors in writing. The study further suggests that teachers and educators need to help native English-speaking learners find strategies that work best for them in terms of learning Chinese connectives.
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Though shoot apical meristems (SAMs) commonly exhibit low or no competence for transformation, the potent regeneration of this tissue merits further research. Especially, when shoot regeneration is recalcitrant using other tissues as explants, SAM probably is an excellent selection. In cockscomb plants, using SAMs from seedlings obtained from MS medium with 0.5 mg l(-1) 6-BA as explants, high frequency of transformation (approximate 20%) is obtained; whereas control SAMs performed poorly for transformation (approximate 3%). These SAMs are malformed in morphology compared to control SAMs. Further observation found that, in these SAMs, cell proliferation and/or TE formation are seen; which are not found in control SAMs. GUS assays indicated that GUS-positive blue spots at TE zones are obvious; whereas the case was contrary in control SAMs. All these data suggest that cell proliferation and/or TE formation might cause high effective transformation. This transformation system should facilitate the use of this species for studies on gene manipulation and expression. Therefore, we introduced 35S:ASL11-GFP to cockscomb via Agrobacterium tumefaciens. ASYMMETRIC LEAVES2-LIKE11 (ASL11) gene of Arabidopsis is a member of the ASYMMETRIC LEAVES2 (AS2)/LATERAL ORGAN BOUNDARIES (LOB) domain gene family, and its function is largely unclear. By confocal laser scanning microscopy, we found that in most over 35S:ASL11-GFP cockscomb plants, ASL11-GFP fusion protein was in discrete nuclear location. These results indicate that the T-DNA contains within the construct inserted into the host chromosomes in an integral form, and also suggest that ASL11 might be a nuclear protein and function as a potential transcription factor. Moreover, SAMs of the over 35S:ASL11-GFP plants show needle-like patterns that lack organ primordial; suggesting ASL11 might be involved in sustaining indeterminate cell fate of SAMs.
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Proteínas de Arabidopsis/genética , Arabidopsis/genética , Celosia/metabolismo , Genes de Plantas/genética , Meristema/metabolismo , Técnicas de Cultivo de Tejidos , Factores de Transcripción/genética , Arabidopsis/citología , Proteínas de Arabidopsis/metabolismo , Glucuronidasa/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Meristema/citología , Fenotipo , Plantas Modificadas Genéticamente , Transporte de Proteínas , Proteínas Recombinantes de Fusión/metabolismo , Fracciones Subcelulares/metabolismo , Factores de Transcripción/metabolismo , Transformación GenéticaRESUMEN
OBJECTIVES: Septic shock is the major cause of childhood mortality. However, the application of corticosteroids remains controversial. This work aimed to analyze the source of controversy based on existing data and recent randomized controlled trials by meta-analysis and to assess whether it can avoid these factors to guide clinical treatment. METHODS: We searched the public databases up to 8 June 2019 and included only randomized controlled trials. The primary outcome was mortality. Sensitivity analysis, subgroup analysis, and dose-response meta-analysis were performed in this work. RESULTS: We included twelve studies consisting of 701 children in the meta-analysis. For primary outcome, the fixed-effect model showed steroids could significantly reduce the mortality compared to the control (Odds Ratio: 0.67; 95% confidence interval: 0.46-0.98; Pâ=â.041). However, the random-effect model showed a negative result (Odds Ratio: 0.69; 95% confidence interval: 0.32-1.51; Pâ=â.252). None of the subgroup results rejected the null hypothesis that the overall effect equaled zero. Dose-response effect analysis showed that increased dosage at a low dosage might reduce the mortality, while at a high dosage, increasing the dose might increase the mortality. Moreover, the grading of recommendations assessment, development, and evaluation level of evidence is low for mortality. CONCLUSIONS: Corticosteroid application is not recommended for septic shock children under current medical conditions.
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Corticoesteroides/uso terapéutico , Choque Séptico/tratamiento farmacológico , Niño , Contraindicaciones de los Medicamentos , HumanosRESUMEN
OBJECTIVES: Myocardial ischaemia/reperfusion (MI/R) injury is associated with adverse cardiovascular outcomes after acute myocardial infarction. However, the molecular mechanisms underlying MI/R injury are unclear. This study investigated the role of long non-coding RNA (lncRNA) Oip5-as1 in regulating mitochondria-mediated apoptosis during MI/R injury. MATERIALS AND METHODS: Sprague-Dawley rats were subjected to MI/R induced by ligation of the left anterior descending coronary artery followed by reperfusion. H9c2 cells were incubated under oxygen-glucose deprivation/reoxygenation (OGD/R) conditions to mimic in vivo MI/R. RT-qPCR and Western blot were used to evaluate gene and protein levels. CCK-8 assay, biochemical assay and flow cytometric analysis were performed to assess the function of Oip5-as1. The dual-luciferase gene reporter assay and RIP assay were conducted as needed. RESULTS: Oip5-as1 expression was downregulated in the hearts of rats with MI/R and in H9c2 cells treated with OGD/R. Oip5-as1 overexpression alleviated reactive oxygen species-driven mitochondrial injury and consequently decreased apoptosis in MI/R rats and H9c2 cells exposed to OGD/R. Mechanistically, Oip5-as1 acted as a competing endogenous RNA of miR-29a and thus decreased its expression. Inhibition of miR-29a reduced the oxidative stress and cytotoxicity induced by OGD/R. Overexpression of miR-29a reversed the anti-apoptotic effect of Oip5-as1 in H9c2 cells treated with OGD/R. Further experiments identified SIRT1 as a downstream target of miR-29a. Oip5-as1 upregulated SIRT1 expression and activated the AMPK/PGC1α pathway by targeting miR-29a, thus reducing the apoptosis triggered by OGD/R. However, these effects were reversed by a selective SIRT1 inhibitor, EX527. CONCLUSIONS: Oip5-as1 suppresses miR-29a leading to activation of the SIRT1/AMPK/PGC1α pathway, which attenuates mitochondria-mediated apoptosis during MI/R injury. Our findings thus provide new insights into the molecular mechanisms of MI/R injury.
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Proteínas Quinasas Activadas por AMP/metabolismo , MicroARNs/metabolismo , Daño por Reperfusión Miocárdica/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , ARN Largo no Codificante/metabolismo , Sirtuina 1/metabolismo , Animales , Apoptosis , Línea Celular , Células Cultivadas , Potencial de la Membrana Mitocondrial , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/fisiopatología , Estrés Oxidativo , ARN Largo no Codificante/fisiología , Ratas Sprague-Dawley , Transducción de SeñalRESUMEN
BACKGROUND: Skipping breakfast is becoming common worldwide. Our previous studies showed that the breakfast prevalence was relatively low. METHODS: In three cross-sectional studies, breakfast prevalence in various populations in Inner Mongolia Medical University campus in 2011, 2013 and 2017 was investigated. Risk of skipping breakfast in 2017 was analyzed. In follow-up study, the incidence, RR, AR% and PAR% of eating and skipping breakfast from 2011 to 2013 were calculated. RESULTS: Data of 18,231 individuals were collected. Breakfast prevalence growth was 16.1% during the seven years. The annulus growth of breakfast prevalence was 9.3% (2013 vs 2011, P < 0.001) and 6.3% (2017 vs 2013, P < 0.001). The breakfast prevalence of three cross-sectional studies (73.0 vs 64.9%, P < 0.001; 79.5 vs 69.6%, P < 0.001; and 82.8 vs 77.4%, P < 0.001) and the breakfast incidence of a two-year follow-up study (70.6 vs 48.5% 95% CI: 1.12-1.90) both showed that breakfast consumption in medical students is higher than that in students from nonmedical faculties. The seven-year average breakfast prevalence of male and female medical students (70.0 and 82.5%) was 1.31 (95% CI: 1.23-1.39) and 1.09 (95% CI: 1.06-1.11) that of male and female students from nonmedical faculties (53.6 and 75.8%), respectively. CONCLUSION: Medical students have a higher breakfast consumption than nonmedical students. Male students from nonmedical faculties have the lowest breakfast prevalence and the highest breakfast skip risk in our university.