Comparison of N uptake and internal use efficiency in two tobacco varieties

AbstractTo 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, 10mmolL−1) and low (LN, 1mmolL−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

Plasticity of Lateral Root Branching in Maize

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

Optimization of Ionic Liquid Based Simultaneous Ultrasonic- and Microwave-Assisted Extraction of Rutin and Quercetin from Leaves of Velvetleaf ( Abutilon theophrasti

An ionic liquids based simultaneous ultrasonic and microwave assisted extraction (ILs-UMAE) method has been proposed for the extraction of rutin (RU), quercetin (QU), from velvetleaf leaves. The influential parameters of the ILs-UMAE were optimized by the single factor and the central composite design (CCD) experiments. A 2.00 M 1-butyl-3-methylimidazolium bromide ([C4mim]Br) was used as the experimental ionic liquid, extraction temperature 60°C, extraction time 12 min, liquid-solid ratio 32 mL/g, microwave power of 534 W, and a fixed ultrasonic power of 50 W. Compared to conventional heating reflux extraction (HRE), the RU and QU extraction yields obtained by ILs-UMAE were, respectively, 5.49 mg/g and 0.27 mg/g, which increased, respectively, 2.01-fold and 2.34-fold with the recoveries that were in the range of 97.62–102.36% for RU and 97.33–102.21% for QU with RSDs lower than 3.2% under the optimized UMAE conditions. In addition, the shorter extraction time was used in ILs-UMAE, compared with HRE. Therefore, ILs-UMAE was a rapid and an efficient method for the extraction of RU and QU from the leaves of velvetleaf

Flow-mediated dilatation to relieve puncture-induced radial artery spasm: A pilot study

  Background: Puncture-induced radial artery spasm (RAS) may extend the duration of coronary an­giography (CAG) or cause transradial access failure. Flow-mediated dilatation (FMD), a widely-used noninvasive approach for assessing endothelial function, was reported to remove the entrapped radial sheath after percutaneous coronary intervention. Herein, the efficacy and safety of FMD in treating puncture-induced RAS before transradial CAG was investigated. Methods: Ninety patients with puncture-induced RAS were randomized in a 1:1:1 ratio into three groups: FMD group was immediately treated with blockage of brachial artery blood for 5 min using a sphygmomanometric cuff and then rapid relief; nitroglycerin (NTG) group was administered with 0.5 mg sublingual NTG instantly; and the no-therapy group was treated with a wait-and-watch strategy. The time of radial pulse recovery, and regional and systemic complications were recorded. Results: The rate of radial pulse recovery within 30 min in FMD group was significantly higher than that in no-therapy group (97% vs. 73%, p = 0.026). The median time to return of radial pulse in FMD group and NTG group was significantly shorter than that in no-therapy group (7 [6.5–9] min vs. 15 [12–18] min, 8 [7–9] min vs. 15 [12–18] min, respectively; both p < 0.001). Headache and decreased blood pressure were more prevalent in NTG group than those in FMD and no-therapy groups. Conclusions: FMD is a feasible, noninvasive and nonpharmacological approach to relieve RAS and facilitate radial artery cannulation after an initial failed attempt. (Cardiol J 2018; 25, 1: 1–6

Root Type-Specific Reprogramming of Maize Pericycle Transcriptomes by Local High Nitrate Results in Disparate Lateral Root Branching Patterns

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

Compared the efficacy of mitoxantrone hydrochloride injection for tracing with radionuclide in sentinel lymph node biopsy of breast cancer

Background and purpose: Both domestic and foreign guidelines recommend the use of radionuclide as sentinel lymph node (SLN) biopsy (SLNB) tracer, however this technique has not been popularized in China for a variety of reasons. Mitoxantrone hydrochloride injection for tracing (MHI), a new strategy to identify lymph nodes, has not been tested for axillary node staging in breast cancer. This multicenter, self-controlled, non-inferiority trial aimed to evaluate the differences between MHI and radionuclide in SLNB tracing. Methods: The trial was conducted across 7 hospitals from December 2019 to December 2020. Patients with early-stage breast cancer received MHI and radionuclide (technetium 99 labeled sulfur colloid, 99mTc-Sc) as SLN tracers during the surgery. The number of SLNs detected and sentinel node detection rates of MHI and radionuclide were counted to evaluate differences in the tracing effects between the two tracers. Results: SLN detection rates of MHI and radionuclide were 96.9% (370/382) and 97.4% (372/382), respectively, with no significant difference (P>0.05). SLNs were co-detected by both tracers in 362 (94.7%) patients; 16 (4.1%) had adverse events possibly related to the trial drugs. Conclusion: In this study, it was found that the lymphatic tracing ability of MHI was not inferior to that of radionuclide. Meanwhile, the use of MHI does not require special instrument/equipment assistance

Temporal and Spatial Profiling of Root Growth Revealed Novel Response of Maize Roots under Various Nitrogen Supplies in the Field

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 (Nmin) 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 Nmin, 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