Crosstalk between in situ root exudates and rhizobacteria to promote rice growth by selenium nanomaterials.

Maximizing the potential of plant-microbe systems offers great opportunities to confront sustainability issues in agroecosystems. However, the dialog between root exudates and rhizobacteria remains largely unknown. As a novel nanofertilizer, nanomaterials (NMs) have significant potential to improve agricultural productivity due to their unique properties. Here, soil amendment with 0.1 mg·kg-1 selenium (Se) NMs (30-50 nm) significantly promoted rice seedling growth. Differences in root exudates and rhizobacteria were evident. At an earlier time point (3rd week), Se NMs increased the relative content of malic and citric acid by 15.4- and 8.1-fold, respectively. Meanwhile, the relative abundances of Streptomyces and Sphingomonas were increased by 164.6 % and 38.3 %, respectively. As the exposure time increased, succinic acid (40.5-fold) at the 4th week and salicylic acid (4.7-fold) and indole-3-acetic (7.0-fold) at the 5th week were enhanced, while Pseudomonas and Bacillus increased at the 4th (112.3 % and 50.2 %) and 5th weeks (190.8 % and 53.1 %), respectively. Further analysis indicated that (1) Se NMs directly enhanced the synthesis and secretion of malic and citric acids by upregulating their biosynthesis and transporter genes and then recruited Bacillus and Pseudomonas; (2) Se NMs upregulated the chemotaxis and flagellar genes of Sphingomonas for more interaction with rice plants, thereby promoting rice growth and stimulating root exudate secretion. This crosstalk of root exudates and rhizobacteria enhanced nutrient uptake, resulting in promoted rice growth. Our study offers insights into the crosstalk between root exudates and rhizobacteria by NMs and provides new insights into rhizosphere regulation in nano-enabled agriculture.

Influence of Management of Intensive Weight, Blood Pressure, and Lipids on Disease Severity in Patients with Carotid Atherosclerosis.

Context: Cardiovascular diseases (CVDs caused by atherosclerosis, such as coronary heart disease and stroke, have become major causes of death and disability worldwide. Atherosclerosis is the primary pathological factor causing CVDs. Managing weight, blood pressure, and lipids is one of the tenets of chronic-disease management, including atherosclerosis. Objective: The study intended to investigate the effects of managing weight, blood pressure, and lipids on disease severity in patients with carotid atherosclerosis. Design: The research team designed a randomized, controlled trial. Setting: The study took place in the pediatric department at the First Hospital of Hebei Medical University in Shijiazhuang, Hebei Province, China. Participants: Participants were 380 patients with carotid atherosclerosis who entered the hospital between March 2018 and June 2020. Intervention: Participants were randomly assigned, using the random-number-table method, to an intervention or a control group, with 190 participants in each group. Both groups received anti-atherosclerotic treatments, and the intervention group also took part in a program for combined management of weight, blood pressure, and blood lipids. Outcome Measures: All measurements occurred at baseline and postintervention. Using a questionnaire, the study measured the changes in the two groups related to alcohol consumption, smoking, high-fat diet, high-salt diet, and lack of exercise. A physical examination provided participants' weights, blood pressures, and lipid levels, and the Self-Care Ability Assessment Scale (ESCA) provided the changes in their self-management ability. A carotid-artery examination measured parameters related to carotid atherosclerosis, including intima-media thickness (IMT), Crouse scores, plaque-class scores, and plaque-grade scores. Results: At baseline, no statistically significant differences existed between the groups. Postintervention, the intervention group had significantly greater decreases than the control group for alcohol consumption, smoking, high-fat diet, high-salt diet, lack of exercise, weight, blood pressure, lipid levels, intima-media thickness (IMT) scores, Crouse scores, and plaque-grade scores. Postintervention, the intervention group had significantly greater increases than the control group for self-responsibility, health knowledge, self-concept, and self-care-skills scores. Conclusions: A program for management of body weight, blood pressure, and blood lipids can effectively control the severity of carotid atherosclerosis, can prevent the disease's progression, and can be promoted as a clinical application.

Bisphenol A effects on the chlorophyll contents in soybean at different growth stages.

Bisphenol A (BPA), a suspected endocrine disruptor, can modify normal plant growth and development. Photosynthesis provides material and energy for the growth and development of plants, in which chlorophyll (Chl) plays a significant role. Many studies have shown that the growth and metabolism of plants vary at different growth stages. Thus the sensitivity of plant's responses to environmental pollution is correspondingly different. We studied the effects of BPA on the Chl contents of soybean (Glycine Max L.) at different growth stages (seedling, flowering and podding, seed-filling and maturation) by measuring the contents of essential intermediates (5-aminolevulinic acid, porphobilinogen, protoporphyrin IX, magnesium protoporphyrin and protochlorophyll) and the activities of key enzymes (5-aminolaevulinic acid dehydratase, porphobilinogen deaminase, uroporphyrinogen III synthase, magnesium chelatase) in chlorophyll synthesis. Low-dose (1.5 mg/L) BPA exposure increased the activities of key enzymes in addition to the contents of intermediates in Chl synthesis at different growth stages, resulting in increases in Chl contents and net photosynthetic rate. In contrast, medium and high-dose (17.2, 50.0 mg/L) BPA exposure produced inhibitory effects on the indices. Following the withdrawal of BPA exposure, the indices recovered to a degree that was related to the plant growth stage. The effect level (high to low) of BPA on these indices at different growth stages was: seedling stage > maturation stage > flowering and podding stage > seed-filling stage. The reverse effect was observed following the withdrawal of BPA exposure. The responses of key enzymes in plant Chl synthesis to BPA illustrate how BPA affects Chl contents. The effects of BPA show clear differences at different plant growth stages.