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Abstract Background Both body mass index (BMI) and genetic factors independently contribute to cardiovascular disease (CVD). However, it is unclear whether genetic risk modifies the association between BMI and the risk of incident CVD. This study aimed to investigate whether BMI categories and genetic risk jointly and interactively contribute to incident CVD events, including hypertension (HTN), atrial fibrillation (AF), coronary heart disease (CHD), stroke, and heart failure (HF). Methods A total of 496,851 participants from the UK Biobank with one or more new-onset CVD events were included in the analyses. BMI was categorized as normal weight (

Abstract Rationale: Quinolone antibiotics are extensively used clinically for human treatment and in agriculture. However, improper and excessive use can lead to the persistence of quinolone residues in animal tissues, potentially accumulating in the human body and posing health risks. Investigating the correlation between mass spectrometry cleavage patterns and molecular structural features enhances the analytical framework for detecting trace or unknown impurities in quinolones. Methods: To collect data, we employed triple quadrupole linear ion trap mass spectrometry in electrospray positive ion mode. Primary mass spectrometry scanning was utilized to confirm parent ions, while secondary mass spectrometry scanning enabled the observation of fragment ions. The cleavage characteristics and pathways of the compounds were inferred from accurate mass‐to‐charge ratios obtained from both primary and secondary mass spectrometry. Results: Under soft ionization conditions, the compounds generally exhibited characteristic fragment ions of [M+H−H2O]+, [M+H−CO]+, and [M+H−H2O−CO]+. Additionally, subtle variations were observed in each compound due to differences in modifying groups. For instance, upon deacidification, the piperazine ring structure underwent breakage and rearrangement, yielding fragment ion peaks devoid of neutral molecules such as C2H5N, C3H7N, or C4H8N. Notably, compounds featuring a cyclopropyl substituent group at the N‐1 position typically exhibited characteristic fragments resulting from the loss of the cyclopropyl radical (⋅C3H5). Moreover, substituents at the N‐1 and C‐8 positions, when linked to form a six‐membered carbocyclic ring, were prone to cleavage, releasing the neutral C3H6 molecule. Conclusion: Quinolone antibiotics share structural similarities in their parent nuclei, leading to partially similar cleavage pathways. Nevertheless, distinct cleavage patterns emerge due to variations in functional groups. According to the difference of mass spectrometry cleavage patterns, it can provide an identification basis for the measured detection of antibiotics.

Background: The unpleasant taste of polyethylene glycol (PEG) has been a hindrance to patients undergoing colonoscopy. Aim: This study aims to determine whether the addition of a vitamin drink (Mizone) to the 4L split-dose PEG regimen would be effective in improving the solution's palatability, and reducing patient discomfort during bowel preparation. Methods: The present prospective, single endoscopist-blinded, randomized controlled study randomly assigned patients into two groups: PEG + Mizone group (3.6 L of PEG solution plus 0.4 L of Mizone) and PEG group (4 L of PEG solution). Palatability was assessed using a Likert scale of 1–5. The adverse events, amount of unconsumed solution, and willingness to repeat the same process were recorded through a questionnaire. The present study was registered in the Chinese Clinical Trial Registry (ChiCTR2000034484). Results: A total of 132 patients were included. The demographic characteristics of these patients were comparable between the two groups. The palatability score (mean ± standard deviation [SD]) was higher in the PEG + Mizone group, when compared to the control group (4.00 ± 0.859 vs. 2.95 ± 0.999, p

Creatine is a naturally occurring derivative of an amino acid commonly utilized in functional foods and pharmaceuticals. Nevertheless, the current industrial synthesis of creatine relies on chemical processes, which may hinder its utilization in certain applications. Therefore, a biological approach was devised that employs whole-cell biocatalysis in the bacterium Corynebacterium glutamicum, which is considered safe for use in food production, to produce safe-for-consumption creatine. The objective of this study was to identify a guanidinoacetate N-methyltransferase (GAMT) with superior catalytic activity for creatine production. Through employing whole-cell biocatalysis, a gamt gene from Mus caroli (Mcgamt) was cloned and expressed in C. glutamicum ATCC 13032, resulting in a creatine titer of 3.37 g/L. Additionally, the study employed a promoter screening strategy that utilized nine native strong promoters in C. glutamicum to enhance the expression level of GAMT. The highest titer was achieved using the P1676 promoter, reaching 4.14 g/L. The conditions of whole-cell biocatalysis were further optimized, resulting in a creatine titer of 5.42 g/L. This is the first report of successful secretory creatine expression in C. glutamicum, which provides a safer and eco-friendly approach for the industrial production of creatine.

High light (HL) significantly impacts plant photosynthesis. This study investigated the effects of different magnesium (Mg) levels (0, 1, 2, and 5 mol Mg plant−1; HMg0, HMg1, HMg2, and HMg5) on tobacco (Nicotiana tabacum L. cv. Cuibi No. 1) under HL (1500 μmol m−2 s−1), aiming to understand the role of Mg in mitigating the impact of HL on photosynthesis and carbon–nitrogen metabolism. Plants treated with 1 mol Mg plant−1 under 750 μmol m−2 s−1 light conditions served as the control. HL led to a reduced chlorophyll (Chl) content and inhibited the maximum photosynthetic rate (Pmax). It also decreased energy involved in photosynthetic electron transfer (ET) and electron flux to reduction end-electron acceptors at the photosystems I (PSI) acceptor side (RE) and caused photosynthetic system damage. H2O2 accumulation exacerbated membrane lipid peroxidation damage, disrupting carbon and nitrogen metabolism, and inducing antioxidant enzyme activity. HMg2 increased Chl content, stomatal conductance, intercellular CO2 concentration, and the net photosynthetic rate compared to HMg0. It enhanced ET efficiency, PSI and PSII functionality, reduced dissipated energy flux (DI), and minimized photosynthesis damage. Conversely, excessive Mg application (HMg5) decreased Pmax and PSII activity, increasing DI. Adequate Mg supply alleviated HL’s detrimental effects by enhancing Chl content and ET and RE efficiency.

In this paper, the stereoselective degradation and quantitative identification of chiral pesticide etoxazole in organisms with different classes of organisms (soil, chlorella algal fluid and mice) were carried out by compound-specific isotope analysis (CSIA). The degradation behavior and stable isotope fractionation effect of etoxazole in soil, chlorella and mice were investigated. The R-etoxazole degraded faster than S-etoxazole in different classes of organisms. The metabolites M1, M2 and M3 were detected in all three substrates. Biodegradation is the main factor for the change of stable isotope ratio of chiral pesticide etoxazole. Furthermore, the relationship between fractionation value of carbon isotope and residual concentration of etoxazole is established by Rayleigh equation, and the biodegradation rate of etoxazole could be calculated by using CSIA without measuring the concentration of etoxazole. Therefore, the use of CSIA can accurately assess the degradation behavior of pesticide pollution in the environment and provide a certain scientific evidence and technical support in the process of environmental remediation.

Gravitational acceleration metrology is the primary means to ensure the international mutual recognition and uniformity of gravity measurement activities, and guarantees the traceability and accuracy of gravity measurement results. Absolute gravimeters are taken as the main tool and carrier for the traceability and transmission of the gravity acceleration value. It can be used as a standard for periodic calibration of the relative gravimeters, as a "ruler" for land, ocean, aviation, and satellite gravity measurement. The National Institute of Metrology (China) has held the First International Comparison in Asia Pacific Regional and the 10th International Comparison of Absolute Gravimeters (ICAG-2017). Based on the former experiences, this paper introduces the preparation, organization and evaluation method of all international comparison measurements. Firstly, the site selection of comparison, observation of vertical gravity gradient, and tidal model before the comparison is introduced. During the comparison, the measurements for the diffraction beam correction and the arrangement of measurement sites were demonstrated. Then, the raw comparison measurements were transferred to the same heights and time, and performed based on the given observation model and constraint equation. After pre-processing, the evaluation of the instrument uncertainty was verified through a compliance test, the degree of instrument equivalence (DoE) and short-term reproducibility were calculated. By analyzing previous comparison results, this paper discusses the significance of international comparison in improving the accuracy of observation data in geophysical research and application, and puts forward some problems faced in the current stage.

Abstract Background and aims Vascular calcification (VC) is a strong predictor of cardiovascular events and all-cause mortality in cardiovascular diseases (CVD). Renal dysfunction is closely related to VC. Serum creatinine, as an important indicator of renal function in chronic kidney disease (CKD), is closely associated with increased VC. Here, to explore the potential role of serum creatinine in CVD, we examined the association between serum creatinine level and aortic arch calcification (AAC) presence in a larger general population. Methods A total of 9067 participants aged > 45 years were included in this study. All participants underwent postero-anterior chest X-ray examination to diagnose AAC. According to the distribution characteristics, serum creatinine levels in male and female were divided into tertiles respectively. Univariate and multivariate logistic regression analysis were used to analyze the association between aortic calcification and serum creatinine. Results Participants included 3776 men and 5291 women, and 611 and 990 AAC were detected, respectively. Serum creatinine level in the female AAC group was significantly higher than that in the non-AAC group (p 45 years old. Measuring serum creatinine levels may assist the early screening individuals at high risk of developing CVD. And higher attention should be given to female's serum creatinine levels in daily clinical practice.

Taking the main bearing-main journal of a six-cylinder diesel engine as the research object，based on the elastic- -fluid lubrication theory and the micro-bump contact theory and considering factors such as journal misalignment and main bearing surface roughness，the main bearing lubrication characteristics model under the flexible whole body is established，and the influence of the main bearing surface profile on the main bearing lubrication characteristics and main journal vibration characteristics is analyzed. The results show that，compared with the result that does not take into account the main bearing surface profile，when the main bearing surface profile is included，the minimum oil film thickness of the main bearing is increased by 75.53%，the maximum oil film pressure is reduced by 6.15%，the average friction loss is reduced by 2%，the horizontal flexural vibration amplitudes of the main journal is reduced by 6%，the vertical flexural vibration amplitudes is reduced by 5%，and both the axial vibration and torsional vibration amplitudes are reduced by 2%. With the increase of the main bearing surface profile height，the minimum oil film thickness of the main bearing increases，the maximum oil film pressure decreases，the average friction loss decreases，and both the maximum roughness contact force amplitude and the number of occurrences are reduced; the amplitudes of flexural vibration，axial vibration and torsional vibration of the main journal are all reduced.

Abstract Large quantities of fertilizers, mainly nitrogen (N), phosphorus (P), and potassium (K), are used in China's crop production; however, whether N, P, and K still limit yield under the current high input remains unknown. In addition, it is not clear whether magnesium (Mg) potentially limits crop production. To address these issues, a national survey of the soil nutrient status and farmers' fertilization practices was conducted in China to determine the soil N, P, K, and Mg status and current fertilization practices. In addition, various experiments, including optimized NPK (OPTNPK) and Mg fertilizer combined with OPTNPK (OPTNPK + Mg) in comparison with farmers' practices (FFP), were performed across China to identify the potential for reducing NPK application and the need for Mg application in crop production. The survey data from 2699 questionnaires indicated that (1) all soil samples were not deficient in NPK, but 73.0% were limited by Mg. (2) The average N, P (in P2O5), K (in K2O), and Mg (in MgO) balances were 422.6, 334.1, 326.3, and −22.6 kg ha−1, respectively. Only 15.7% of all farmers applied Mg fertilizer. (3) NPK fertilization can be reduced by an average of 28.8% without reducing the crop yield and quality. (4) For most crops, the application of Mg fertilizer increased the crop yield by 5.5–40.6% and improved the quality. However, different crops under different conditions had different responses to Mg fertilization. These results indicate that reduced NPK inputs and increased Mg inputs are equally important for the healthy development and sustainability of China's agriculture.

Background Vascular calcification (VC), associated with enhanced cardiovascular morbidity and mortality, is characterized by the osteogenic transdifferentiation of vascular smooth muscle cells. Inflammation promotes VC initiation and progression. Interleukin (IL)‐29, a newly discovered member of type III interferon, has recently been implicated in the pathogenesis of autoimmune diseases. Here we evaluated the role of IL‐29 in the VC process and underlying inflammatory mechanisms. Methods and Results The mRNA expression of IL‐29 was significantly increased and positively associated with an increase in BMP2 (bone morphogenetic protein 2) mRNA level in calcified carotid arteries from patients with coronary artery disease or chronic kidney disease. IL‐29 and BMP2 proteins are colocalized in human calcified arteries. IL‐29 binding to its specific receptor IL‐28Rα (IL‐28 receptor α) (IL‐29/IL‐28Rα) inhibited the proliferation of rat vascular smooth muscle cells without altering cell apoptosis or migration. IL‐29 promoted the calcification of rat vascular smooth muscle cells and their osteogenic transdifferentiation in vitro as well as the rat aortic ring calcification ex vivo, induced by the calcification medium or osteogenic medium. The procalcification effect of IL‐29 was reduced by pharmacological inhibition of IL‐29/IL‐28Rα binding as well as suppression of janus kinase 2/signal transducer and activator of transcription pathway activation, accompanied by decreased BMP2 expression in the cultured rat vascular smooth muscle cells. Conclusions These results suggest an important role of IL‐29 in VC development, at least partly, via activating the janus kinase 2/signal transducer and activator of transcription 3 signaling. Inhibition of IL‐29 or its specific receptor, IL‐28Rα, may provide a novel strategy to reduce VC in patients with vascular diseases.

Abstract Objective This study was aimed to determine how platelet reactivity (PR) on dual antiplatelet therapy predicts ischemic and bleeding events in patients underwent percutaneous coronary intervention (PCI). Design A total of 2768 patients who had received coronary stent implantation and had taken aspirin 100 mg in combination with clopidogrel 75 mg daily for > 5 days were consecutively screened and 1885 were enrolled. The recruited patients were followed-up for 12 months. The primary end-point was the net adverse clinical events (NACE) of cardiovascular death, nonfatal myocardial infarction (MI), target vessel revascularization (TVR), stent thrombosis (ST) and any bleeding. Result 1709 patients completed the clinical follow-up. By using the receiver operating characteristic (ROC) curve analysis, the optimal cut-off values were found to be 37.5 and 25.5% respectively in predicting ischemic and bleeding events. Patients were classified into 2 groups according to PR: inside the window group (IW) [adenosine diphosphate (ADP) induced platelet aggregation (PLADP) 25.5–37.4%)] and outside the window group (OW) (PLADP

Background: Previous studies have suggested that proton pump inhibitors could impair the antiplatelet effect of clopidogrel. It is uncertain whether ilaprazole affects the antiplatelet effect of clopidogrel. This study aimed to determine the drug-drug interaction between ilaprazole and clopidogrel.Methods: A randomized crossover trial of 40 healthy subjects was performed. Clopidogrel was administered alone or in combination with ilaprazole for 7 days. The maximal platelet aggregation (MPA) to 5 μmol/L adenosine diphosphate was measured by light transmission aggregometry and the platelet reactivity index (PRI) was determined by vasodilator-stimulated phosphoprotein P2Y12 assay. High on-treatment platelet reactivity (HOPR) was defined as a MPA of >40%. The inhibition of platelet aggregation (IPA) and PRI in the two phases were compared between two regimens after the last dosing.Results: IPA was comparable between the two regimens at 0, 10 and 24 h (p > 0.05), but higher at 4 h in the clopidogrel alone regimen compared with that in the combined treatment regimen (75.66 ± 18.44% vs. 70.18 ± 17.67%, p = 0.031). The inhibition of PRI was comparable between the two regimens at 0 and 24 h. There were no significant differences in the area under the time-IPA% curve (AUC) or the incidence of HOPR at all time-points between the two regimens.Conclusion: In healthy subjects, ilaprazole has limited effect on the pharmacodynamics of clopidogrel and it may not be clinically relevant.Clinical Trial Registration: [www.chictr.org.cn], identifier [ChiCTR2000031482].

Taking the main bearing of a diesel engine as the study object， the lubrication state analysis model of the main bearing is established by taking the roughness and elastic deformation of the main bearing surface into account， and the influence of the radial profile of the main bearing on the lubrication state is analyzed. The results show that， compared with the calculated results without considering the radial journal profile， when the influence of the radial journal profile is taken into account， the minimum oil film thickness of the main bearing increases by 25.95%， the maximum oil film pressure decreases by 17.69%， the mean friction power loss decreases by 6.14% and the inclination of the spindle neck is improved. With the increase of journal roughness， the minimum oil film thickness increases， the maximum oil film pressure almost invariably， and the mean friction power loss increases.

Background Insulin receptor substrate‐1 (IRS‐1) rs956115 is associated with vascular risk in patients with coronary artery disease and concomitant diabetes. CYP2C19*2 (rs4244285) modulates clopidogrel response and predicts the outcome of coronary artery disease. This study was designed to explore the association between IRS‐1, CYP2C19*2 genotypes, platelet reactivity, and 1‐year outcome in patients with coronary artery disease undergoing percutaneous coronary intervention. Methods and Results Genotyping was performed using an improved multiplex ligation detection reaction technique. Platelet aggregation was assessed by light transmission aggregometry. Major adverse cardiovascular events were defined as a composite of cardiovascular death, myocardial infarction, and ischemic stroke. A total of 2213 consecutive patients were screened and 1614 were recruited. At 1 month, patients with IRS‐1 CG genotype had significantly lower levels of ADP‐induced platelet aggregation compared with patients with CC homozygotes. Patients with IRS‐1 CG or GG genotype had a 2.09‐fold higher risk of major adverse cardiovascular events compared with those with CC homozygotes (95% CI, 1.04–4.19; P=0.0376). By comparison, patients with CYP2C19*2 GA or AA genotype had higher ADP‐induced platelet aggregation compared with patients with GG homozygotes. Although there was no significant difference in risk of major adverse cardiovascular events between patients with GA/AA and GG genotypes, patients with GA genotype had a 2.19‐fold higher risk than those with GG homozygotes (95% CI, 1.13–4.24; P=0.0200). No interaction between IRS‐1 and CYP2C19*2 genotypes was observed. Conclusions In patients following percutaneous coronary intervention, IRS‐1 GG/CG and CYP2C19*2 GA genotypes were associated with 2.09‐ and 2.19‐fold increased cardiovascular risk, respectively, at 1‐year follow‐up. The association between IRS‐1 genotypes and major adverse cardiovascular events appeared to be independent of known clinical predictors. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01968499.

Objective To investigate the value of a SnapECG monitoring in diagnosing arrhythmias compared with the conventional management. Methods In the first phase, the SnapECG and 12-lead electrocardiogram (ECG) were simultaneously adopted to detect arrhythmias in 439 hospitalized patients. The accuracies of the SnapECG in detecting different arrhythmias were assessed. In the second phase, 62 patients with palpitations were randomized to receive the SnapECG monitoring or conventional management for 3 months. The diagnosis rate, time of diagnosis, episodes before diagnosis, associated expenses, and scores of the modified European Heart Rhythm Association (EHRA), Self-rating Anxiety Scale (SAS), and the 36-item short-form health survey questionnaire (SF-36) were compared between groups. Results In the first phase, the SnapECG monitoring showed a sensitivity of 83.55% and specificity of 96.79% in identifying tachyarrhythmias, and a sensitivity of 95.29% and specificity of 97.54% in identifying bradyarrhythmias. In the second phase, 1642 ECGs were recorded by the SnapECG, among which 290 abnormal ECGs were identified. Compared with the conventional management, the SnapECG monitoring increased the diagnosis rate of symptomatic arrhythmias (70.97% vs. 19.35%, P < 0.05), shortened the time of diagnosis (48.26 ± 36.78 days vs. 71.45 ± 30.01 days, P < 0.05) and consequently reduced the episodes of symptomatic arrhythmias prior to establishing diagnosis. The scores of modified EHRA, SAS, SF-36 significantly improved at 3-month compared with their baseline levels in the SnapECG group. Conclusions Remote monitoring with the SnapECG can achieve early diagnosis of symptomatic arrhythmias. However, its sensitivity in identifying P-wave-related arrhythmias warrants further improvement.

Magnesium (Mg) is an essential nutrient for a wide array of fundamental physiological and biochemical processes in plants. It largely involves chlorophyll synthesis, production, transportation, and utilization of photoassimilates, enzyme activation, and protein synthesis. As a multifaceted result of the introduction of high-yielding fertilizer-responsive cultivars, intensive cropping without replenishment of Mg, soil acidification, and exchangeable Mg (Ex-Mg) leaching, Mg has become a limiting nutrient for optimum crop production. However, little literature is available to better understand distinct responses of plants to Mg deficiency, the geographical distribution of soil Ex-Mg, and the degree of Mg deficiency. Here, we summarize the current state of knowledge of key plant responses to Mg availability and, as far as possible, highlight spatial Mg distribution and the magnitude of Mg deficiency in different cultivated regions of the world with a special focus on China. In particular, ~55% of arable lands in China are revealed Mg-deficient (< 120 mg kg−1 soil Ex-Mg), and Mg deficiency literally becomes increasingly severe from northern (227–488 mg kg−1) to southern (32–89 mg kg−1) China. Mg deficiency primarily traced back to higher depletion of soil Ex-Mg by fruits, vegetables, sugarcane, tubers, tea, and tobacco cultivated in tropical and subtropical climate zones. Further, each unit decline in soil pH from neutral reduced ~2-fold soil Ex-Mg. This article underscores the physiological importance of Mg, potential risks associated with Mg deficiency, and accordingly, to optimize fertilization strategies for higher crop productivity and better quality.

Myocardial infarction (MI) is one of the leading causes of death worldwide, and knowing the early warning signs of MI is lifesaving. To expand our knowledge of MI, we analyzed plasma metabolites in MI and non-MI chest pain cases to identify markers for alerting about MI occurrence based on metabolomics. A total of 230 volunteers were recruited, consisting of 146 chest pain patients admitted with suspected MI (85 MIs and 61 non-MI chest pain cases) and 84 control individuals. Non-MI cardiac chest pain cases include unstable angina (UA), myocarditis, valvular heart diseases, etc. The blood samples of all suspected MI cases were collected not longer than 6 h since the onset of chest pain. Gas chromatography–mass spectrometry and liquid chromatography–mass spectrometry were applied to identify and quantify the plasma metabolites. Multivariate statistical analysis was utilized to analyze the data, and principal component analysis showed MI could be clearly distinguished from non-MI chest pain cases (including UA and other cases) in the scores plot of metabolomic data, better than that based on the data constructed with medical history and clinical biochemical parameters. Pathway analysis highlighted an upregulated methionine metabolism and downregulated arginine biosynthesis in MI cases. Receiver operating characteristic curve (ROC) and adjusted odds ratio (OR) were calculated to evaluate potential markers for the diagnosis and prediction ability of MI (MI vs. non-MI cases). Finally, gene expression profiles from the Gene Expression Omnibus (GEO) database were briefly discussed to study differential metabolites' connection with plasma transcriptomics. Deoxyuridine (dU), homoserine, and methionine scored highly in ROC analysis (AUC > 0.91), sensitivity (>80%), and specificity (>94%), and they were correlated to LDH and AST (p < 0.05). OR values suggested, after adjusting for gender, age, lipid levels, smoking, type II diabetes, and hypertension history, that high levels of dU of positive logOR = 3.01, methionine of logOR = 3.48, and homoserine of logOR = 1.61 and low levels of isopentenyl diphosphate (IDP) of negative logOR = −5.15, uracil of logOR = −2.38, and arginine of logOR = −0.82 were independent risk factors of MI. Our study highlighted that metabolites belonging to pyrimidine, methionine, and arginine metabolism are deeply influenced in MI plasma samples. dU, homoserine, and methionine are potential markers to recognize MI cases from other cardiac chest pain cases after the onset of chest pains. Individuals with high plasma abundance of dU, homoserine, or methionine have increased risk of MI, too.

Extensively branched root systems can efficiently capture soil resources by increasing their absorbing surface in soil. Lateral roots are the roots formed from pericycle cells of other roots that can be of any type. As a consequence, lateral roots provide a higher surface to volume ratio and are important for water and nutrients acquisition. Discoveries from recent studies have started to shed light on how plant root systems respond to environmental changes in order to improve capture of soil resources. In this Mini Review, we will mainly focus on the spatial distribution of lateral roots of maize and their developmental plasticity in response to the availability of water and nutrients.

Dipeptidyl peptidase-4 (DPP-4) inhibitors are novel anti-hyperglycemic drugs for type 2 diabetes. It has been reported that DDP-4 inhibitor could exert pleiotropic effects on cardiovascular system. This study was to explore the effect and mechanism of vildagliptin on the stenosis of injured carotid artery in diabetic mouse. Twenty six-week-old male db/db mice (BKS) were randomized into vildagliptin treated and vehicle control groups. Ligation injury was first performed in left carotid arteries of all diabetic mice, then oral vildagliptin or equal amount of PBS was correspondingly administered to the mice from the next day to ligation injury for 4 weeks. Effects on proliferation were detected via histological and morphometric analysis. Endoplasmic reticulum (ER) stress and nuclear factor kappa B (NF-κB) markers were determined by immunoblot analysis. After 4 weeks of vildagliptin delivery, it was observed that the intimal area and neointimal thickness of the ligated carotid arteries were significantly reduced as compared to the control group. In vivo, vildagliptin suppressed the expressions of PCNA and α-SMA, phospho-p65, phospho-IKKα/β, GRP78 and CHOP, as well as IRE-1 in vascular smooth muscle cells (VSMCs). In vitro, the proliferation and hypertrophy of VSMCs were significantly inhibited by blocking the IRE-1 pathway, and the inhibition of phospho-IRE-1 expression down-regulated the expression of phospho-IKKα/β in VSMCs. Vildagliptin reduced the stenosis of injured carotid arteries in diabetic mice, and this effect was achieved via inhibiting the activation of ER stress/NF-κB pathway.

To explain the observation in field experiments that tobacco variety CB-1 was more nitrogen (N)-efficient than K326, the influence of two N levels on growth, N uptake and N flow within plants of the two tobacco varieties was studied. Xylem sap from the upper and lower leaves of both tobacco varieties cultured in quartz sand was collected by application of pressure to the root system. CB-1 took up more N with smaller roots at both high (HN, 10 mmol L− 1) and low (LN, 1 mmol L− 1) N levels, and built up more new tissues in upper leaves especially at LN level, than K326. Both varieties showed luxury N uptake, and CB-1 accumulated significantly less NO3− in new tissues than K326, when grown at the HN level. At both N levels, the amount of xylem-transported N and phloem-cycled N from shoot to root in K326 was greater than those in CB-1, indicating higher N use efficiency in CB-1 shoots than in K326 shoots. The major nitrogenous compound in the xylem sap was NO3− irrespective of N level and variety. Low N supply did not cause more NO3− reduction in the root. The results indicated that the N-efficient tobacco variety CB-1 was more efficient in both N uptake by smaller roots and N utilization in shoots, especially when grown at the LN level.

HOX transcript antisense intergenic RNA (HOTAIR) is a long non-coding RNA (lncRNA) that functions as an oncogenic molecule in different cancer cells. Genetic variants of HOTAIR may affect the activity of certain regulatory factors and further regulate the aberrant expression of HOTAIR, which might be underlying mechanisms that affect tumour susceptibility and prognosis. Recently, several studies have been performed to examine the possible link between polymorphisms in HOTAIR and cancer risk; however, the results have been inconclusive. Therefore, we performed a meta-analysis to estimate the associations between HOTAIR polymorphisms (rs920778, rs4759314 and rs1899663) and cancer risk. Eight studies comprising 7,151 cases and 8,740 controls were included in our study. Overall, no significant associations between the HOTAIR polymorphisms (rs920778, rs4759314 and rs1899663) and cancer risk were observed. However, in further stratified analyses, the variant T allele of rs920778 exhibited a significant increased risk of developing digestive cancers (dominant model: OR = 1.44; 95% CI = 1.31-1.59). These findings provided evidence that HOTAIR rs920778 may modify the susceptibility to certain cancer types. Further studies incorporating subjects with different ethnic backgrounds combined with re-sequencing of the marked region and functional evaluations are warranted.

Excessive N fertilization results in low N-use efficiency (NUE) without any yield benefits and can have profound, long-term environmental consequences including soil acidification, N leaching and increased production of greenhouse gases. Improving NUE in crop production has been a longstanding, worldwide challenge. A crucial strategy to improve NUE is to enhance N uptake by roots. Taking maize as a model crop, we have compared root dry weight (RDW), root/shoot biomass ratio (R/S), and NUE of maize grown in the field in China and in western countries using data from 106 studies published since 1959. Detailed analysis revealed that the differences in the RDW and R/S of maize at silking in China and the western countries were not derived from variations in climate, geography, and stress factors. Instead, NUE was positively correlated with R/S and RDW; R/S and NUE of maize varieties grown in western countries were significantly greater than those grown in China. We then testified this conclusion by conducting field trials with representative maize hybrids in China (ZD958 and XY335) and the US (P32D79). We found that US P32D79 had a better root architecture for increased N uptake and removed more mineral N than Chinese cultivars from the 0-60 cm soil profile. Reported data and our field results demonstrate that a large and deep root, with an appropriate architecture and higher stress tolerance (higher plant density, drought and N deficiency), underlies high NUE in maize production. We recommend breeding for these traits to reduce the N-fertilizer use and thus N-leaching in maize production and paying more attention to increase tolerance to stresses in China.

Larger, and deeper, root systems of new maize varieties, compared to older varieties, are thought to have enabled improved acquisition of soil resources and, consequently, greater grain yields. To compare the spatial distributions of the root systems of new and old maize varieties and their relationships with spatial variations in soil concentrations of available nitrogen (N), phosphorus (P) and potassium (K), two years of field experiments were performed using six Chinese maize varieties released in different eras. Vertical distributions of roots, and available N, P and K in the 0-60 cm soil profile were determined in excavated soil monoliths at silking and maturity. The results demonstrated that new maize varieties had larger root dry weight, higher grain yield and greater nutrient accumulation than older varieties. All varieties had similar total root length and vertical root distribution at silking, but newer varieties maintained greater total root length and had more roots in the 30-60 cm soil layers at maturity. The spatial variation of soil mineral N (Nmin) in each soil horizon was larger than that of Olsen-P and ammonium-acetate-extractable K, and was inversely correlated with root length density (RLD), especially in the 0-20 cm soil layer. It was concluded that greater acquisition of mineral nutrients and higher yields of newer varieties were associated with greater total root length at maturity. The negative relationship between RLD and soil Nmin at harvest for all varieties suggests the importance of the spatial distribution of the root system for N uptake by maize.

OBJECTIVE: The relationship between admission serum calcium levels and in-hospital mortality in patients with acute ST-segment elevation myocardial infarction (STEMI) has not been well definitively explored. The objective was to assess the predictive value of serum calcium levels on in-hospital mortality in STEMI patients. METHODS: From 2003 to 2010, 1431 consecutive STEMI patients admitted to the First Affiliated Hospital of Nanjing Medical University were enrolled in the present study. Patients were stratified according to quartiles of serum calcium from the blood samples collected in the emergency room after admission. Between the aforementioned groups,the baseline characteristics, in-hospital management, and in-hospital mortality were analyzed. The association of serum calcium level with in-hospital mortality was calculated by a multivariable Cox regression analysis. RESULTS: Among 1431 included patients, 79% were male and the median age was 65 years (range, 55-74). Patients in the lower quartiles of serum calcium, as compared to the upper quartiles of serum calcium, were older, had more cardiovascular risk factors, lower rate of emergency revascularization,and higher in-hospital mortality. According to univariate Cox proportional analysis, patients with lower serum calcium level (hazard ratio 0.267, 95% confidence interval 0.164-0.433, p

A challenge for Chinese agriculture is to limit the overapplication of nitrogen (N) without reducing grain yield. Roots take up N and participate in N assimilation, facilitating dry matter accumulation in grains. However, little is known about how the root system in soil profile responds to various N supplies. In the present study, N uptake, temporal and spatial distributions of maize roots, and soil mineral N (N(min)) were thoroughly studied under field conditions in three consecutive years. The results showed that in spite of transient stimulation of growth of early initiated nodal roots, N deficiency completely suppressed growth of the later-initiated nodal roots and accelerated root death, causing an early decrease in the total root length at the rapid vegetative growth stage of maize plants. Early N excess, deficiency, or delayed N topdressing reduced plant N content, resulting in a significant decrease in dry matter accumulation and grain yield. Notably, N overapplication led to N leaching that stimulated root growth in the 40-50 cm soil layer. It was concluded that the temporal and spatial growth patterns of maize roots were controlled by shoot growth and local soil N(min), respectively. Improving N management involves not only controlling the total amount of chemical N fertilizer applied, but also synchronizing crop N demand and soil N supply by split N applications.

Objectives. To observe the short- and long-term outcomes after percutaneous coronary intervention (PCI) in octogenarians (>80 y.o.) at our institution. Method. All octogenarians who underwent PCI during the study period were retrospectively retrieved from our database and clinically followed. Major adverse cardiac (and cerebral) events (MAC(C)E) was considered as primary outcome. Results. From January 2003 to December 2007, 140 octogenarians (mean age: 85±3 y.o., 79% of male) underwent PCI and were clinically followed 14±11 months. Procedural success was obtained in 100 percent of patients with single vessel disease, in 96 percent of patients with double vessel disease, and in 75 percent of patients with triple vessel disease. In-hospital, 30 days, and one year MACE rates were 5%, 5%, and 10.7%, respectively. Impaired left ventricular (LV) ejection fraction (hazard ratio (HR)=0.909, 95% confidence interval (CI)=0.856 to 0.964, 𝑃=.002), diabetes mellitus (HR=5.792, 95% CI=1.785 to 18.796, 𝑃=.003), and low GFR (HR=2.943, 95% CI=1.161, to 7.464, 𝑃=.023) were independently associated with an increase risk of MACE at long-term followup. Conclusion. Coronary angiography can be successfully performed in elderly patients with single and double vessel disease. The results in triple vessel disease are encouraging. Low LV function, diabetes, and impaired renal function increase the risk of long-term major adverse cardiac events.

This article summarizes a study conducted on patients with coronary artery disease (CAD) who underwent percutaneous coronary intervention (PCI) and were treated with clopidogrel. The study aimed to identify factors that may predict high on-treatment platelet reactivity (HOPR) in these patients. The results showed that low red blood cell (RBC) counts, high body mass index (BMI), and statin consumption were independent predictors of HOPR. The study was supported by various funding sources. [Extracted from the article]

Clopidogrel is a pro-drug which needs two-step metabolism to produce the active thiol metabolite. This study aimed to explore an efficient method to simultaneously determine the plasma clopidogrel, 2-oxo-clopidogrel (2- Oxo-CLP), and the clopidogrel active metabolite (CAM). A high-throughput liquid chromatography tandem mass spectrometry (LC-MS/MS) was therefore developed. The analytes were extracted from plasma by using methyl tert-butyl ether (MTBE). Chromatographic separation was performed on a C18 column under an isocratic elution, accompanied with acetonitrile and deionized water containing 0.1% formic acid. After optimizing the condition of LC-MS/MS, a stable linearity was observed in the standard curves over the concentration ranges of 0.05 to 50.0 ng/mL for clopidogrel, 0.5 to 50.0 ng/mL for 2-Oxo-CLP, and 0.5 to 100 ng/mL for clopidogrel active metabolite derivative (CAMD). The retention time was 4.78 minutes, 3.79 minutes, 3.59 minutes, and 4.82 minutes for clopidogrel, 2-Oxo-CLP, CAMD, and internal standard, respectively. Both the relative standard deviation and the relative error were within the requirement of operating criteria. No significant degradation of clopidogrel, 2-OxoCLP, and CAMD occurred under different storage conditions. This method was successfully validated in 3 patients with coronary artery disease. The results showed that the current LC-MS/MS method was efficient for simultaneously detecting clopidogrel, 2-Oxo-CLP, and CAM with fine linearity, accuracy, precision, and stability. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the mass accretion properties in the innermost regions of a viscously evolved protoplanetary disk and try to find some clues to the outburst events. In our newly developed one-dimensional time-dependent disk model based on the diffusion equation for surface density, we take into account the following physical effects: the gravitational collapse of the parent molecular cloud core, the irradiation from the central star to the disk, the effect of the photoevaporation mechanism, the viscosity due to the magnetorotational instability (MRI) and the gravitational instability (GI), and the thermal ionization mechanism in the inner regions. We find that the mass accretion rate M·disk in the innermost regions is statistically high enough to generate outbursts, although there are regions where the accretion rate is low. Additionally, we find that there is a weak correlation between the high mass accretion rate M·disk and the molecular cloud core’s properties (angular velocity ω and mass Mcd), as well as a strong correlation with the minimum viscosity parameter αmin. In general, there are two regions of outburst, the inner Region I and outer Region II. The outburst of Region I is caused by the MRI mechanism and thermal instability, while neither the MRI, the GI, nor the thermal instability causes the outburst of Region II. Our analysis suggests that the outer Region II is dominated by, or largely related to, the Rosseland mean opacity κR and the αmin parameter.

Maize (Zea mays) plants exhibit altered carbon partitioning under nitrogen (N) deficiency, but the mechanisms by which N availability affects sugar export out of leaves and transport into developing ears remain unclear. Maize was grown under field conditions with different N supply. Plant growth, sugar movement, and starch turnover in source or sink tissues were investigated at silking and 20 or 21 days after silking. Nitrogen deficiency stunted plant growth and grain yield compared with N-sufficient plants, and resulted in greater starch concentrations in leaves due to more as well as larger starch granules in bundle sheath cells. Transmission electron microscopy revealed an open symplastic pathway for sucrose movement in N-deficient leaves, while the expression levels of transporters responsible for sucrose efflux and phloem loading were lower than in N-sufficient leaves. Nonetheless, greater starch concentrations in the apical cob portion of N-deficient plants implied sufficient carbon supply relative to the diminished sink strength (decreased kernel number and weight). Together with the high sugar concentrations in the developing kernels, the results indicated that reduced sink capacity and sugar utilization during grain filling may limit the yield in N-deficient plants, which in turn imposes a feedback inhibition on sugar export from leaves. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) grain yield is considered to be highly associated with carbohydrate dynamics in leaves and developing ears during the critical period bracketing silking. Carbohydrate changes are sensitive to variation in nitrogen (N) availability, yet a comprehensive analysis of the N effect on various carbohydrate concentrations around silking remains elusive. A 2-yr field study was conducted to investigate grain yield, N uptake, ear dry matter and carbohydrate concentrations in ear-leaves and whole ears (prior to silking) and kernels (after silking) of maize grown with 0, 150, and 300 kg N ha-1. Greater N availability increased maize shoot dry matter and N content at silking and physiological maturity, as well as grain yield. While N had little effect on ear-leaf glucose concentration, sucrose concentration increased but starch concentration decreased with increasing N, regardless of sampling time. Prior to silking, glucose and fructose concentrations in the developing ear responded positively to increasing N availability, but sucrose and starch concentrations declined. In growing kernels shortly after silking, glucose and fructose concentrations in N fertilized treatments were significantly lower than those in the zero-N treatment. In contrast, a significant increase in kernel starch concentration was found in response to 300 kg N ha-1. These observations point to an important role of the carbohydrate composition of unpollinated ears prior to silking with regard to kernel set and post-silking kernel starch accumulation, and thus final crop yield. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) and faba bean (Vicia faba L.) have contrasting responses to low phosphorus (P) supply. The aim of this work was to characterise these responses with respect to the partitioning of biomass between shoot and root and biochemical modification of the rhizosphere. Maize and faba bean were grown in rhizoboxes in soil with a low P (10 mg kg-1) or high P (150 mg kg-1) supply. Solutions were collected from rhizosphere and bulk soil by suction, using micro-rhizons in situ. The pH and water-soluble P (Pi) were determined on the solutions collected by using micro-rhizons. Olsen P, soil pH and acid phosphatase activity were determined on samples of rhizosphere and bulk soil. Organic acids released from root tips were collected non-destructively and analysed by high performance liquid chromatography. Plants grown with low P supply had higher ratios of root : shoot dry weight than plants grown with high P supply. This response was greater in maize than in faba bean. Rhizosphere acidification, organic acid concentrations and acid phosphatase activity were greater in faba bean than maize. The Pi concentration in the maize rhizosphere solution was less than in the bulk soil, but the Pi concentration in the rhizosphere solution of faba bean was greater than in the bulk soil. It was concluded that maize responded to low P supply by investing more biomass in its root system, but acidification, concentrations of organic acids, acid phosphatase activity and mobilisation of P in the rhizosphere were greater in faba bean than in maize. [ABSTRACT FROM AUTHOR]

The adaptability of root system architecture to unevenly distributed mineral nutrients in soil is a key determinant of plant performance. The molecular mechanisms underlying nitrate dependent plasticity of lateral root branching across the different root types of maize are only poorly understood. In this study, detailed morphological and anatomical analyses together with cell type-specific transcriptome profiling experiments combining laser capture microdissection with RNA-seq were performed to unravel the molecular signatures of lateral root formation in primary, seminal, crown, and brace roots of maize (Zea mays) upon local high nitrate stimulation. The four maize root types displayed divergent branching patterns of lateral roots upon local high nitrate stimulation. In particular, brace roots displayed an exceptional architectural plasticity compared to other root types. Transcriptome profiling revealed root type-specific transcriptomic reprogramming of pericycle cells upon local high nitrate stimulation. The alteration of the transcriptomic landscape of brace root pericycle cells in response to local high nitrate stimulation was most significant. Root type-specific transcriptome diversity in response to local high nitrate highlighted differences in the functional adaptability and systemic shoot nitrogen starvation response during development. Integration of morphological, anatomical, and transcriptomic data resulted in a framework underscoring similarity and diversity among root types grown in heterogeneous nitrate environments. [ABSTRACT FROM AUTHOR]

Background and Aims: Shoot-borne roots contribute to most of the nutrient uptake throughout the life cycle of maize (Zea mays). Compared with numerous studies with embryonic roots, detailed information on the phenotypic plasticity of shoot-borne roots in response to a heterogeneous nitrogen supply is scarce. The present study therefore provides a comprehensive profile of fine-scale plastic responses of distinct root types to localized high nitrate supply. Methods: Seedlings of the maize inbred line B73 were grown in split-root systems. The anatomy and morphological plasticity of the primary root and the roots initiated from the 2nd, 5th and 7th shoot nodes, and their lateral roots, were studied in response to local high nitrate supply to one side of the root system. Key Results: In contrast to the insensitivity of axial roots, local high nitrate supply increased the length of 1st-order lateral roots on the primary root and the three whorls of shoot-borne roots at different growth stages, and increased the density of 1st-order lateral roots on the 7th shoot-borne root after silking. The length and density of 2nd-order lateral roots on the three whorls of shoot-borne roots displayed a more flexible response to local high nitrate than 1st-order lateral roots. Root diameter and number, and total area and diameter of metaxylem vessels increased from the primary root to early and then later developed shoot-borne roots, which showed a positive relationship with shoot growth and N accumulation. Conclusions: Maize axial roots and lateral roots responded differently to local high nitrate, and this was related to their function. The extent of morphological plasticity of lateral roots in response to local high nitrate depended on the initiation time of the shoot-borne roots on which the lateral roots developed. Morphological plasticity was higher on 2nd-order than on 1st-order lateral roots. The results suggest that higher order lateral root branching might be a potential target for genetic improvement in future maize breeding. [ABSTRACT FROM AUTHOR]

Plants have evolved a unique plasticity of their root system architecture to flexibly exploit heterogeneously distributed mineral elements from soil. Local high concentrations of nitrate trigger lateral root initiation in adult shoot-borne roots of maize (Zea mays) by increasing the frequency of early divisions of phloem pole pericycle cells. Gene expression profiling revealed that, within 12 h of local high nitrate induction, cell cycle activators (cyclin-dependent kinases and cyclin B) were up-regulated, whereas repressors (Kip-related proteins) were down-regulated in the pericycle of shoot-borne roots. In parallel, a ubiquitin protein ligase S-Phase Kinase-Associated Protein1-cullin-F-box proteinS-Phase Kinase-Associated Protein 2B-related proteasome pathway participated in cell cycle control. The division of pericycle cells was preceded by increased levels of free indole-3-acetic acid in the stele, resulting in DR5-red fluorescent protein-marked auxin response maxima at the phloem poles. Moreover, laser-capture microdissectionbased gene expression analyses indicated that, at the same time, a significant local high nitrate induction of the monocot-specific PIN-FORMED9 gene in phloem pole cells modulated auxin efflux to pericycle cells. Time-dependent gene expression analysis further indicated that local high nitrate availability resulted in PIN-FORMED9-mediated auxin efflux and subsequent cell cycle activation, which culminated in the initiation of lateral root primordia. This study provides unique insights into how adult maize roots translate information on heterogeneous nutrient availability into targeted root developmental responses. [ABSTRACT FROM AUTHOR]

We sought to assess the incidence of aspirin resistance after off-pump coronary artery bypass (OPCAB) surgery, and investigate whether clopidogrel can improve aspirin response and be safely applied early after OPCAB surgery. Sixty patients who underwent standard OPCAB surgery were randomized into two groups. One group (30 patients) received mono-antiplatelet treatment (MAPT) with aspirin 100 mg daily and the other group received dual antiplatelet treatment (DAPT) with aspirin 100 mg daily plus clopidogrel 75 mg daily. Platelet aggregations in response to arachidonic acid (PLAA) and adenosine diphosphate (ADP) (PLADP) were measured preoperatively and on days 1 to 6, 8 and 10 after the antiplatelet agents were administered. A PLAA level above 20% was defined as aspirin resistance. Postoperative bleeding and other perioperative variables were also recorded. There were no significant differences between the two groups in baseline characteristics, average number of distal anastomosis, operation time, postoperative bleeding, ventilation time and postoperative hospital stay. However, the incidence of aspirin resistance was significantly lower in the DAPT group than that in the MAPT group on the first and second day after antiplatelet agents were given (62.1% vs. 32.1%, 34.5% vs. 10.7%, respectively, both P < 0.05). There was no significant difference in postoperative complication between the two groups. DAPT with aspirin and clopidogrel can be safely applied to OPCAB patients early after the procedure. Moreover, clopidogrel reduces the incidence of OPCAB-related aspirin resistance. [ABSTRACT FROM AUTHOR]

Cardiac troponin-I (cTnI) and -T (cTnT) are sensitive and specific markers of myocardial injury. However, the role of increased cTnI and cTnT in percutaneous coronary intervention (PCI)-related myocardial injury remains controversial. In this prospective, single-center and double-blind study, we aimed to determine the diagnostic and prognostic value of cTnI as well as cTnT (cTns) in PCI-related myocardial injury in a Chinese population. A total of 1,008 patients with stable angina pectoris and non-ST-segment elevation acute coronary syndrome were recruited. The levels of cTnI and cTnT were examined before and after PCI. All patients were followed up for 26±9 months to observe the incidence of major adverse cardiac events (MACEs). Our results showed that post-PCI cTnI and/or cTnT levels were increased to more than the 99th percentile upper reference limit (URL) in 133 (13.2%) patients, among which 22 (2.2%) were more than 5 x 99th percentile URL. By univariate analysis, an elevation in cTns after PCI was not an independent predictor of increased MACEs, HR 1.35 (P 5 0.33, 95%CI: 0.74-2.46). In conclusion, our data demonstrate that the incidence of PCI-related myocardial injury is not common in a Chinese population and minor elevated cTns levels may not be a sensitive prognostic marker for MACEs. [ABSTRACT FROM AUTHOR]

Approximately 35-55% of total nitrogen (N) in maize plants is taken up by the root at the reproductive stage. Little is known about how the root of an adult plant responds to heterogeneous nutrient supply. In this study, root morphological and physiological adaptations to nitrate-rich and nitrate-poor patches and corresponding gene expression of ZmNrt2.1 and ZmNrt2.2 of maize seedlings and adult plants were characterized. Local high nitrate (LoHN) supply increased both lateral root length (LRL) and density of the treated nodal roots of adult maize plants, but only increased LRL of the treated primary roots of seedlings. LoHN also increased plant total N acquisition but not N influx rate of the treated roots, when expressed as per unit of root length. Furthermore, LoHN markedly increased specific root length (m g−1) of the treated roots but significantly inhibited the growth of the lateral roots outside of the nitrate-rich patches, suggesting a systemic carbon saving strategy within a whole root system. Surprisingly, local low nitrate (LoLN) supply stimulated nodal root growth of adult plants although LoLN inhibited growth of primary roots of seedlings. LoLN inhibited the N influx rate of the treated roots and did not change plant total N content. The gene expression of ZmNrt2.1 and ZmNrt2.2 of the treated roots of seedlings and adult plants was inhibited by LoHN but enhanced by LoLN. In conclusion, maize adult roots responded to nitrate-rich and nitrate-poor patches by adaptive morphological alterations and displayed carbon saving strategies in response to heterogeneous nitrate supply. [ABSTRACT FROM AUTHOR]

Nitrogen (N) limitation reduces leaf growth and photosynthetic rates of maize ( Zea mays), and constrains photosynthate translocation to developing ears. Additionally, the period from about 1 week before to 2 weeks after silking is critical for establishing the reproductive sink capacity necessary to attain maximum yield. To investigate the influence of carbohydrate availability in plants of differing N status, a greenhouse study was performed in which exogenous sucrose (Suc) was infused around the time of silking into maize stems grown under different N regimes. N deficiency significantly reduced leaf area, leaf longevity, leaf chlorophyll content and photosynthetic rate. High N-delayed leaf senescence, particularly of the six uppermost leaves, compared to the other two N treatments. While N application increased ear leaf soluble protein concentration, it did not influence glucose and suc concentrations. Interestingly, ear leaf starch concentration decreased with increasing N application. Infusion of exogenous suc tended to increase non-structural carbohydrate concentrations in the developing ears of all N treatments at silking and 6 days after silking. However, leaf photosynthetic rates were not affected by suc infusion, and suc infusion failed to increase grain yield in any N treatment. The lack of an effect of suc infusion on ear growth and the high ear leaf starch concentration of N-deficient maize, suggest that yield reduction under N deficiency may not be due to insufficient photosynthate availability to the developing ear during silking, and that yield reduction under N deficiency may be determined at an earlier growth stage. [ABSTRACT FROM AUTHOR]

Background: In order to identify miRNAs expression profiling from genome-wide screen for diagnosis of acute myocardial infarction (AMI) and angina pectoris (AP), we investigated the altered profile of serum microRNAs in AMI and AP patients at a relative early stage. Methods: Serum samples were taken from 117 AMI patients, 182 AP patients and 100 age-and gender-matched controls. An initial screening of miRNAs expression was performed by Solexa sequencing. Differential expression was validated using RT-qPCR in individuals samples, the samples were arranged in a two-phase selection and validation. Results: The Solexa sequencing results demonstrated marked upregulation of serum miRNAs in AMI patients compared with controls. RT-qPCR analysis identified a profile of six serum miRNAs (miR-1, miR-134, miR-186, miR-208, miR-223 and miR-499) as AMI biomarkers. MiR-208 and miR-499 were elevated higher in AP cases than in AMI cases. The ROC curves indicated a panel of six miRNAs has a great potential to offer sensitive and specific diagnostic tests for AMI. More especially, the panel of six miRNAs presents significantly differences between the AMI and AP cases. Conclusions: The six-miRNAs signature identified from genome-wide serum miRNA expression profiling may serves as a fingerprint for AMI and AP diagnosis. [ABSTRACT FROM AUTHOR]

Potassium fertilization is uncommon in the North China Plain (NCP), especially in maize (Zea mays L.) production. Our specific objectives in this study were to determine yield response to K fertilization as affected by conventional as well as high-yielding production practices. Seven field experiments were conducted in the NCP. The factorial study compared three levels of K fertilization (K0 = no K; K1 = medium K rate; K2 = high K rate) and two levels of production practices: conventional (CP) and high yielding (HP). At all sites, HP outperformed CP in terms of maize grain yield except at ZD in 2006. On average, maize grain yields were enhanced by 9.9 and 14.9% under CP and 15.7 and 21.0% under HP at the K1 and K2 levels, respectively. Maize yield response, as well as economic profit from applied K, were greater under HP than CP, on average, across seven site-years. Medium K inputs improved partial factor productivity (PFP) of applied N and P, while higher rates had inconsistent results. Overall, PFP and agronomic efficiency of applied K were improved under HP, as was the apparent recovery efficiency of applied K, which suggests positive interactions among K and other high-yielding production practices. Negative K balances were observed in all of the K0 and K1 treatments in both years and under both production practices, especially under HP. In intensive agricultural soils of the NCP with higher K content relative to South China, optimal K fertilization will improve soil fertility and support high grain yield. [ABSTRACT FROM AUTHOR]

Root growth and mineral nutrient uptake are two closely related physiological processes regulated by shoot growth and development. To date, little attention has been paid to the effects of leaves and ears on root growth and mineral nutrient uptake. To unravel this physiological puzzle, we treated inbred and hybrid maize (Zea mays L.) plants by shading middle leaves or covering ears from silking onward in two growing seasons under field conditions. We found that shading middle leaves reduced photosynthetic capacity and assimilate allocation to roots and, thus, decreased root growth. However, there was relatively less reduction in total N content of whole plants than that of the root dry wt. of all genotypes, implying that roots of these plants had a higher N uptake rate per unit root dry wt. than the control. In contrast, covering ears suppressed grain development, allowing more assimilate relocation into roots to promote root growth. On the other hand, removal of substantial sink demand (grain filling) directly caused decrease in total N uptake, and the decrease in N content in the shoot was significant in four out of seven genotypes, although the cob and husks could partially substitute for developing grains as a nutrient sink to influence nutrient (N) uptake by roots. Our results suggested that root growth and nutrient uptake (N in this study) were nonsynchronous due to differential regulation primarily by assimilate allocation and shoot demand, respectively. [ABSTRACT FROM AUTHOR]

Nitrogen (N) over-application is a serious problem in intensive agricultural production areas with consequent large N losses and environmental pollution. In contrast to N, potassium (K) application has been neglected in many developing countries and this has resulted in soil K depletion in agricultural ecosystems and prevented increases in crop yields. Nitrogen-potassium interaction is currently a topic of interest in many studies and the focus of this review is K nutrition under varied N regimes. Nitrogen form and application rate and time influence soil K fixation and release, as well as K uptake, transport, cycling and reutilization within crops. High yielding quality crops can be obtained by optimal N: K nutritional ratios. High rates of applications of N and K do not necessarily lead to increased yield increments and may even reduce yield. Yield response to K uptake depends on N nutritional status and the interaction is usually positive when NO-N is supplied. Antagonism between NH and K in uptake was mostly attributed to simple competitive effects in the past while evidence showing mixed-noncompetitive interactions existed. Two components of membrane transport systems for K uptake by plants are a high-affinity K transport system which is inhibited by NH and a low-affinity K transport system which is relatively NH insensitive. Potassium is highly mobile within plants but its flow and partitioning can change depending on the forms of N supply. NH nutrition in comparison to NO-supply results in more K translocation to leaves. A better understanding of the mechanism of N-K interaction can be a useful guide to best nutrient management in agricultural practice in order to achieve high yields with high nutrient use efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Field studies were conducted from 2000 to 2002 to quantify how the accumulation and distribution of dry matter and K+ in tobacco plants (Nicotiana tabacum L. variety K326 in 2000 and 2002, and Nicotiana tabacum L. variety Yun 85 in 2001) affects the K+ concentration in leaves after apex excision. Dry matter accumulation (DMA) in K326 increased after apex excision but then decreased as the leaves began to mature, while DMA in Yun 85 continuously increased after apex excision. As leaves matured, a net decrease of dry matter occurred sequentially in lower leaves, middle leaves, upper leaves, and even in stems and roots for K326 but only in lower leaves for Yun 85. The patterns of K+ uptake by roots and changes in K+ content and concentration in different plant organs were similar for all three years of the study. K+ content was highest 12–20 days after apex excision and then decreased; until the final harvest of leaves, K+ content decreased 15% in 2000, 10% in 2001, and 30% in 2002. Moreover, a net export of K+ occurred from leaves to stem and roots such that the percentage of K+ in leaves vs. the whole plant dropped from 65% at the time of apex excision to 58% at the last harvest, while that of stem plus roots increased from about 35% at the time of apex excision to about 42% at the last harvest. The K+ concentration in all plant organs continuously decreased after apex excision with time. Overall, the results indicate the K+ concentration in leaves decreases after apex excision because (1) plant dry matter increases at a greater rate than K+ uptake (the dilution effect), (2) there is a net decrease in K+ content, and (3) K+ is transported from leaves to stems and roots. [Copyright &y& Elsevier]