Putrescine Alleviates Iron Deficiency via NO-Dependent Reutilization of Root Cell-Wall Fe in Arabidopsis.

Plants challenged with abiotic stress show enhanced polyamines levels. Here, we show that the polyamine putrescine (Put) plays an important role to alleviate Fe deficiency. The adc2-1 mutant, which is defective in Put biosynthesis, was hypersensitive to Fe deficiency compared with wild type (Col-1 of Arabidopsis [Arabidopsis thaliana]). Exogenous Put decreased the Fe bound to root cell wall, especially to hemicellulose, and increased root and shoot soluble Fe content, thus alleviating the Fe deficiency-induced chlorosis. Intriguingly, exogenous Put induced the accumulation of nitric oxide (NO) under both Fe-sufficient (+Fe) and Fe-deficient (-Fe) conditions, although the ferric-chelate reductase (FCR) activity and the expression of genes related to Fe uptake were induced only under -Fe treatment. The alleviation of Fe deficiency by Put was diminished in the hemicellulose-level decreased mutant-xth31 and in the noa1 and nia1nia2 mutants, in which the endogenous NO levels are reduced, indicating that both NO and hemicellulose are involved in Put-mediated alleviation of Fe deficiency. However, the FCR activity and the expression of genes related to Fe uptake were still up-regulated under -Fe+Put treatment compared with -Fe treatment in xth31, and Put-induced cell wall Fe remobilization was abolished in noa1 and nia1nia2, indicating that Put-regulated cell wall Fe reutilization is dependent on NO. From our results, we conclude that Put is involved in the remobilization of Fe from root cell wall hemicellulose in a process dependent on NO accumulation under Fe-deficient condition in Arabidopsis.

Bioaugmentation with syntrophic volatile fatty acids-oxidizing consortia to alleviate the ammonia inhibition in continuously anaerobic digestion of municipal sludge.

Ammonia inhibition easily affects the performance of anaerobic digestion (AD) for municipal sludge and the oxidization of volatile fatty acids (VFAs) is the rate-limiting step of this process. Bioaugmentation is considered to be an effective method to alleviate ammonia inhibition of AD, but most study used the hydrogenotrophic methanogens as the bioaugmentation culture. In this study, bioaugmentation of mesophilic AD (MAD) and thermophilic AD (TAD) under ammonia inhibition with syntrophic acetate and propionate oxidizing consortia was investigated. The results showed that the bioaugmented reactors recovered earlier than control reactors with 20 (MAD) and 8 (TAD) days, respectively. The high-throughput 16S rRNA gene sequencing indicated that the relative abundance of carbohydrates fermenter (Lentimicrobium), syntrophic VFAs-oxidizing bacteria (Rikenellaceae_DMER64, Smithella and Syntrophobacter) and acetoclastic and hydrogenotrophic methanogens (Methanosaeta, Methanolinea and Methanospirillum) increased in MAD after bioaugmentation. However, part of the bioaugmentation culture could not adapt to the high free ammonia (FAN) concentration in MAD and the effect was weakened. In TAD, proteolytic bacteria (Keratinibaculum and Tepidimicrobium), syntrophic VFAs-oxidizing bacteria (Syntrophomonas) and hydrogenotrophic methanogen (Methanosarcina) were strengthened. The effect of bioaugmentation in TAD was durable even at higher organic loading rate (OLR), due to its positive influence on microbial community. These results suggested that the different bioaugmentation mechanism occurred in MAD and TAD, which are derived from the synergetic effects of ammonia tolerance and microbial interactions. Our study revealed the VFAs-oxidizing consortia as bioaugmented culture could be the potential strategy to alleviate the ammonia stress of AD.

[Utility of waist-to-height ratio in detecting central obesity and related adverse cardiovascular risk among normal weight adults].

OBJECTIVE: To detect central obesity and related adverse cardiovascular disease risk factors by waist-to-height ratio (WHR) among normal weight adults in Chongqing area. METHODS: A total of 20 000 participants aged 18 - 59 from one hour economic cycle of Chongqing area were selected by group sampling method. We measured the height, waist circumference (WC), body weight, blood pressure, blood lipid and blood sugar. Body Mass Index (BMI) and WHR were computed. We analyzed the differences of the correlated indexes between non-central obesity group (WHR < 0.5) and central obesity group (WHR ≥ 0.5) of those had normal weight (18.5 ≤ BMI (kg/m(2)) < 24). And we used logistic regression method to analyze the relation between central obesity and related adverse cardiovascular risk factors. RESULTS: Among 11 612 normal weight subjects, 1801 (15.51%) participants were normal weight central obesity. Of non-central obesity group and central obesity group, the levels of waist WC were (73.71 ± 5.91) and (84.47 ± 4.58) cm (F = 328.74, P < 0.01); diastolic blood pressure levels were (72.85 ± 10.30) and (78.22 ± 11.90) mm Hg (1 mm Hg = 0.133 kPa, F = 23.62, P < 0.01); triglyceride levels were (1.22 ± 0.95), (1.97 ± 1.91) mmol/L (F = 114.70, P < 0.01); total cholesterol levels were (4.66 ± 0.84) and (5.04 ± 0.92) mmol/L (F = 13.10, P < 0.01); high density lipoprotein levels were (1.41 ± 0.31), (1.25 ± 0.29) mmol/L (F = 29.44, P < 0.01); low density lipoprotein levels were (2.65 ± 0.74) and (3.03 ± 0.77) mmol/L (F = 9.98, P < 0.01); glycemia levels were (4.94 ± 0.82) and (5.25 ± 1.37) mmol/L (F = 47.21, P < 0.01). The results of the logistic regression analysis showed the central obesity normal weight group was 1.28 (1.02 - 1.60), 1.49 (1.20 - 1.84), 2.24 (1.92 - 2.60), 1.77 (1.53 - 2.05), 1.58 (1.15 - 2.16) and 1.31 (1.06 - 1.63) times more likely than the normal group to have significantly elevated levels of systolic blood pressure, diastolic blood pressure, triglyceride, high density lipoprotein, low density lipoprotein and blood glucose. CONCLUSION: WHR can effectively reflect the normal weight central obesity and the risk factors of cardiovascular disease;the adverse cardiovascular disease risk was high among normal weight central obesity adults.

Safety and efficacy of remote ischemic postconditioning after thrombolysis in patients with stroke.

OBJECTIVE: To determine the effect of remote ischemic postconditioning (RIPC) on patients with acute ischemic stroke (AIS) undergoing IV thrombolysis (IVT). METHODS: A single-center randomized controlled trial was performed with patients with AIS receiving IVT. Patients in the RIPC group were administered RIPC treatment (after IVT) during hospitalization. The primary endpoint was a score of 0 or 1 on the modified Rankin scale (mRS) at day 90. The safety, tolerability, and neuroprotection biomarkers associated with RIPC were also evaluated. RESULTS: We collected data from both the RIPC group (n = 34) and the control group (n = 34). The average duration of hospitalization was 11.2 days. There was no significant difference between 2 groups at admission for the NIH Stroke Scale score (p = 0.364) or occur-to-treatment time (p = 0.889). Favorable recovery (mRS score 0-1) at 3 months was obtained in 71.9% of patients in the RIPC group vs 50.0% in the control group (adjusted odds ratio 9.85, 95% confidence interval 1.54-63.16; p = 0.016). We further found significantly lower plasma S100-ß (p = 0.007) and higher vascular endothelial growth factor (p = 0.003) levels in the RIPC group than in the control group. CONCLUSIONS: Repeated RIPC combined with IVT can significantly facilitate recovery of nerve function and improve clinical prognosis of patients with AIS. CLINICALTRIALSGOV IDENTIFIER: NCT03218293. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that RIPC after tissue plasminogen activator treatment of AIS significantly increases the proportion of patients with an MRS score of 0 or 1 at 90 days.

Soil Nutrients Drive Function and Composition of phoC-Harboring Bacterial Community in Acidic Soils of Southern China.

Phosphorus (P) deficiency is an important factor that limits the agricultural production potential in acidic soils. The bacterial phoC gene encodes non-specific acid phosphatase (ACP), which participates in the mineralization of soil organic P and is therefore important for the improvement of soil P availability. However, the function and community population of phoC-harboring bacteria and their driving factors in acidic soil remain largely unknown. For this study, 51 soil samples and 207 plant samples were collected from four locations in the acidic soil region of southern China. Quantitative PCR and high-throughput sequencing were employed to analyze abundance and community composition of phoC-harboring bacteria. The results showed that soil P availability was the important nutrient element limiting the growth of both plants and soil bacteria. Soil ACP activity was clearly higher than alkaline phosphatase, indicating the important effect of phoC-harboring bacteria in acidic soils. ACP activity and phoC gene abundance showed a significant positive correlation, and both were closely related to soil available P, total carbon, and total nitrogen. The dominant genera of phoC-harboring bacteria involved Cupriavidus, Stenotrophomonas, and Xanthomonas. Compared to land-use pattern, sampling location, and soil parent material, soil property played a more important role in affecting phoC-harboring bacterial community structure, where N-related variables including soil NO 3 - -N, NH 4 + -N, and C/N ratio appeared to be the main factors. These findings suggest that phoC-harboring bacteria should provide an important contribution to soil P availability in acidic soil, and its function and community composition were strongly associated with soil nutrients.

Light-induced Variation in Phenolic Compounds in Cabernet Sauvignon Grapes (Vitis vinifera L.) Involves Extensive Transcriptome Reprogramming of Biosynthetic Enzymes, Transcription Factors, and Phytohormonal Regulators.

Light environments have long been known to influence grape (Vitis vinifera L.) berry development and biosynthesis of phenolic compounds, and ultimately affect wine quality. Here, the accumulation and compositional changes of hydroxycinnamic acids (HCAs) and flavonoids, as well as global gene expression were analyzed in Cabernet Sauvignon grape berries under sunlight exposure treatments at different phenological stages. Sunlight exposure did not consistently affect the accumulation of berry skin flavan-3-ol or anthocyanin among different seasons due to climatic variations, but increased HCA content significantly at véraison and harvest, and enhanced flavonol accumulation dramatically with its timing and severity degree trend. As in sunlight exposed berries, a highly significant correlation was observed between the expression of genes coding phenylalanine ammonia-lyase, 4-coumarate: CoA ligase, flavanone 3-hydroxylase and flavonol synthase family members and corresponding metabolite accumulation in the phenolic biosynthesis pathway, which may positively or negatively be regulated by MYB, bHLH, WRKY, AP2/EREBP, C2C2, NAC, and C2H2 transcription factors (TFs). Furthermore, some candidate genes required for auxin, ethylene and abscisic acid signal transductions were also identified which are probably involved in berry development and flavonoid biosynthesis in response to enhanced sunlight irradiation. Taken together, this study provides a valuable overview of the light-induced phenolic metabolism and transcriptome changes, especially the dynamic responses of TFs and signaling components of phytohormones, and contributes to the further understanding of sunlight-responsive phenolic biosynthesis regulation in grape berries.