Effects of maternal methyl donor intake during pregnancy on ileum methylation and function in an intrauterine growth restriction pig model

Background Intrauterine growth retardation(IUGR)affects intestinal growth,morphology,and function,which leads to poor growth performance and high mortality.The present study explored whether maternal dietary methyl donor(MET)supplementation alleviates IUGR and enhances offspring’s growth performance by improving intestinal growth,function,and DNA methylation of the ileum in a porcine IUGR model.Methods Forty multiparous sows were allocated to the control or MET diet groups from mating until delivery.After farrowing,8 pairs of IUGR and normal birth weight piglets from 8 litters were selected for sampling before suckling colostrum.Results The results showed that maternal MET supplementation tended to decrease the IUGR incidence and increased the average weaning weight of piglets.Moreover,maternal MET supplementation significantly reduced the plasma concentrations of isoleucine,cysteine,urea,and total amino acids in sows and newborn pig-lets.It also increased lactase and sucrase activity in the jejunum of newborn piglets.MET addition resulted in lower ileal methionine synthase activity and increased betaine homocysteine S-methyltransferase activity in the ileum of newborn piglets.DNA methylation analysis of the ileum showed that MET supplementation increased the methyla-tion level of DNA CpG sites in the ileum of newborn piglets.Down-regulated differentially methylated genes were enriched in folic acid binding,insulin receptor signaling pathway,and endothelial cell proliferation.In contrast,up-regulated methylated genes were enriched in growth hormone receptor signaling pathway and nitric oxide biosyn-thetic process.Conclusions Maternal MET supplementation can reduce the incidence of IUGR and increase the weaning litter weight of piglets,which may be associated with better intestinal function and methylation status.

Concerns about the application of resistance exercise with blood-flow restriction and thrombosis risk in hemodialysis patients

Background:Hemodialysis(HD) per se is a risk factor for thrombosis.Considering the growing body of evidence on blood-flow restriction(BFR) exercise in HD patients,identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training model.The aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise(RE) with BFR on this molecule.Methods:Two hundred and six HD patients volunteered for this study(all with a glomerular filtration rate of <15 mL/min/1.73 m2).The RE+BFR session consisted of 50% arterial occlusion pressure during 50 min sessions of HD(intradialytic exercise).RE repetitions included concentric and eccentric lifting phases(each lasting 2 s) and were supervised by a strength and conditioning specialist.Results:Several variables were associated with elevated levels of D-dimer,including higher blood glucose,citrate use,recent cardiovascular events,recent intercurrents,higher inflammatory status,catheter as vascular access,older patients(>70 years old),and HD vintage.Furthermore,RE+BFR significantly increases D-dimer after 4 h.Patients with borderline baseline D-dimer levels(400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range(≥500 ng/mL).Conclusion:These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE+BFR.D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE+BFR.

Mechanisms underlying the role of endoplasmic reticulum stress in the placental injury and fetal growth restriction in an ovine gestation model

Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine model of pregnancy.We hypothesized that the FGR results from the BPA-induced insufficiency and barrier dysfunction of the placenta,oxidative stress,inflammatory responses,autophagy and endoplasmic reticulum stress(ERS).However,precise mechanisms underlying the BPA-induced placental dysfunction,and subsequently,FGR,as well as the potential involvement of placental ERS in these complications,remain to be investigated.Methods In vivo experiment,16 twin-pregnant(from d 40 to 130 of gestation)Hu ewes were randomly distributed into two groups(8 ewes each).One group served as a control and received corn oil once a day,whereas the other group received BPA(5 mg/kg/d as a subcutaneous injection).In vitro study,ovine trophoblast cells(OTCs)were exposed to 4 treatments,6 replicates each.The OTCs were treated with 400μmol/L BPA,400μmol/L BPA+0.5μg/m L tunicamycin(Tm;ERS activator),400μmol/L BPA+1μmol/L 4-phenyl butyric acid(4-PBA;ERS antagonist)and DMEM/F12 complete medium(control),for 24 h.Results In vivo experiments,pregnant Hu ewes receiving the BPA from 40 to 130 days of pregnancy experienced a decrease in placental efficiency,progesterone(P4)level and fetal weight,and an increase in placental estrogen(E2)level,together with barrier dysfunctions,OS,inflammatory responses,autophagy and ERS in type A cotyledons.In vitro experiment,the OTCs exposed to BPA for 24 h showed an increase in the E2 level and related protein and gene expressions of autophagy,ERS,pro-apoptosis and inflammatory response,and a decrease in the P4 level and the related protein and gene expressions of antioxidant,anti-apoptosis and barrier function.Moreover,treating the OTCs with Tm aggravated BPA-induced dysfunction of barrier and endocrine(the increased E2 level and decreased P4 level),OS,inflammatory responses,autophagy,and ERS.However,treating the OTCs with 4-PBA reversed the counteracted effects of Tm mentioned above.Conclusions In general,the results reveal that BPA exposure can cause ERS in the ovine placenta and OTCs,and ERS induction might aggravate BPA-induced dysfunction of the placental barrier and endocrine,OS,inflammatory responses,and autophagy.These data offer novel mechanistic insights into whether ERS is involved in BPA-mediated placental dysfunction and fetal development.

Associations of serum D-dimer and glycosylated hemoglobin levels with third-trimester fetal growth restriction in gestational diabetes mellitus

BACKGROUND Gestational diabetes mellitus(GDM)is a special type of diabetes that commonly occurs in women during pregnancy and involves impaired glucose tolerance and abnormal glucose metabolism;GDM is diagnosed for the first time during pregnancy and can affect fetal growth and development.AIM To investigate the associations of serum D-dimer(D-D)and glycosylated hemoglobin(HbA1c)levels with third-trimester fetal growth restriction(FGR)in GDM patients.METHODS The clinical data of 164 pregnant women who were diagnosed with GDM and delivered at the Obstetrics and Gynecology Hospital of Fudan University from January 2021 to January 2023 were analyzed retrospectively.Among these women,63 whose fetuses had FGR were included in the FGR group,and 101 women whose fetuses had normal body weights were included in the normal body weight group(normal group).Fasting venous blood samples were collected from the elbow at 28-30 wk gestation and 1-3 d before delivery to measure serum D-D and HbA1c levels for comparative analysis.The diagnostic value of serum D-D and HbA1c levels for FGR was evaluated by receiver operating characteristic analysis,and the influencing factors of third-trimester FGR in GDM patients were analyzed by logistic regression.RESULTS Serum fasting blood glucose,fasting insulin,D-D and HbA1c levels were significantly greater in the FGR group than in the normal group,while the homeostasis model assessment of insulin resistance values were lower(P<0.05).Regarding the diagnosis of FGR based on serum D-D and HbA1c levels,the areas under the curves(AUCs)were 0.826 and 0.848,the cutoff values were 3.04 mg/L and 5.80%,the sensitivities were 81.0%and 79.4%,and the specificities were 88.1%and 87.1%,respectively.The AUC of serum D-D plus HbA1c levels for diagnosing FGR was 0.928,and the sensitivity and specificity were 84.1%and 91.1%,respectively.High D-D and HbA1c levels were risk factors for third-trimester FGR in GDM patients(P<0.05).CONCLUSION D-D and HbA1c levels can indicate the occurrence of FGR in GDM patients in the third trimester of pregnancy to some extent,and their combination can be used as an important index for the early prediction of FGR.

The Effect of Macronutrient Restrictions on Gut Microbiome and Biochemical Parameters of Wistar Albino Rats

Macronutrients serve as a source of energy for both gut microbiota and its host. An increase or decrease in macronutrients can either increase or decrease the composition of gut microbiota, leading to gut dysbiosis which has been implicated in many diseases state including non-communicable diseases. To achieve this, seven diets were formulated by restricting 60% of each macronutrient. These diets were fed on 42 albino rats (Wistar), divided into 7 groups of 6 rats each. Group 1 was fed on a normal laboratory chow diet (ND), group 2 received a fat-restricted diet (FRD), group 3 received a protein-restricted diet, (PFD), group 4 received a carbohydrate-restricted diet (CRD), group 5 received a protein and fat-restricted diet (PFRD), group 6 re-ceived a carbohydrate and fat-restricted diet (CFRD) and group 7 received a carbohydrate and protein-restricted diet (CPRD). Feed and water intake were given ad libitum and daily weight and food intake were recorded. The experiment went on for 4 weeks after which animals were sacrificed and intestinal content and blood were collected for analysis (gut microbial composition, glucose, insulin levels, serum lipid, and enzyme). Compared to the control group results showed a decrease in Bacteroides (40.50 - 14.00 CFU), HDL (68.20 - 40.40 mg/dl), and AST (66.62 - 64.74 U/L) in FRD. An increase in AST (66.6 - 69.43 U/L), Bifidobacterial (59.50 - 92.00 CFU) and decreased Bacteroides (40.5 - 19.5 CFU) for PRD was also recorded. CRD reduced Lactobacillus (73 - 33.5 CFU), total bacterial count (129 - 48 CFU), HDL (68.2 - 30.8 mg/dl), and cholesterol (121.44 - 88.65 mg/dl) whereas intestinal composition of E. coli (30.5 - 51.5 CFU) increased. PFRD increased Lactobacillus (73.00 - 102.5 CFU), Bifidobacterial (59.5 - 100 CFU), HDL (68.2 - 74.7 mg/dl), and Triglyceride (111.67 - 146.67 mg/dl) concentration. Meanwhile, a reduction in Bifidobacterial (59.5 - 41.5 CFU), and an increasing of AST (66.62 - 70.30 U/l) were recorded for CFRD. However, Bacteroides (40.5 69.5 CFU), LDL (30.95 - 41.98 mg/dl) increased and Bifidobacterial (59.5 - 38.00 CFU) and HDL (68.2 - 53.5 mg/dl) decreased for CPRD. This work, therefore, concludes that macronutrient restriction causes significant changes in serum marker and enzyme profile, and gut microbial composition which can cause gut dysbiosis and later on could expose the host to inflammatory diseases in the long run.

双波长激光联合生物陶瓷材料iRoot SP辅助磨牙根管治疗效果分析

目的:探讨双波长激光联合生物陶瓷材料iRoot SP辅助磨牙根管治疗的效果。方法:选择2020年1月—2023年6月收治的104例磨牙根管治疗患者,按照随机数字表法分为对照组与试验组,每组52例。对照组采用iRoot SP糊剂进行根管充填,试验组以双波长激光(Nd:YAG和Er:YAG)联合iRoot SP糊剂进行治疗。比较2组总有效率、疼痛程度及并发症,观察治疗前、治疗后6周及12周的血清白细胞介素6(IL-6)、白细胞介素17(IL-17)、肿瘤坏死因子α(TNF-α)、出血指数(bleeding index,BI)、牙周探诊深度(depth of periodontal probing,PD)和临床附着水平(clinical attachment level,CAL)。采用SPSS 22.0软件包对数据进行统计学分析。结果:试验组总有效率显著高于对照组,根管填充后疼痛程度显著低于对照组(P<0.05);试验组治疗后6、12周的IL-6、IL-17、TNF-α、BI、PD和CAL显著低于对照组(P<0.05)。结论:双波长激光联合生物陶瓷材料iRoot SP辅助磨牙根管治疗效果较为理想,有利于减轻牙周炎症和疼痛程度。

Long-term implications of fetal growth restriction

Fetal growth restriction(FGR),or intrauterine growth restriction(IUGR),is a complication of pregnancy where the fetus does not achieve its genetic growth potential.FGR is characterized by a pathological retardation of intrauterine growth velocity in the curve of intrauterine growth.However,the FGR definition is still debated,and there is a lack of a uniform definition in the literature.True IUGR,compared to constitutional smallness,is a pathological condition in which the placenta fails to deliver an adequate supply of oxygen and nutrients to the developing fetus.Infants with IUGR,compared to appropriately grown gestational age infants,have a significantly higher risk of mortality and neonatal complications with long-term consequences.Several studies have demonstrated how suboptimal fetal growth leads to long-lasting physiological alterations for the developing fetus as well as for the newborn and adult in the future.The long-term effects of fetal growth retardation may be adaptations to poor oxygen and nutrient supply that are effective in the fetal period but deleterious in the long term through structural or functional alterations.Epidemiologic studies showed that FGR could be a contributing factor for adult chronic diseases including cardiovascular disease,metabolic syndrome,diabetes,respiratory diseases and impaired lung function,and chronic kidney disease.In this review we discussed pathophysiologic mechanisms of FGR-related complications and potential preventive measures for FGR.

牙体牙髓病根管治疗应用iRoot SP冷侧法的效果

目的探讨牙体牙髓病根管治疗应用iRoot SP冷侧法的效果。方法筛选2018-06至2020-06在解放军总医院京南医疗区就诊的牙体牙髓病患者100例,随机分为对照组和试验组,每组50例,均进行根管治疗,其中对照组充填根管采用热牙胶垂直加压法,试验组采用iRoot SP冷侧法。比较两组根管充填效果、临床总有效率、疼痛视觉模拟评分(VAS)及咀嚼功能。结果两组治疗后根管充填效果和临床总有效率比较,差异无统计学意义(P>0.05);试验组治疗后1周[(4.13±0.79)vs.(5.11±0.98)]及1个月[(2.45±0.37)vs.(3.11±0.67)]VAS评分低于对照组,治疗后咬合力[(131.25±11.21)lbs vs.(120.34±14.09)lbs]及咀嚼效率[(90.12±4.13)%vs.(78.98±7.45)%]均优于对照组,差异均有统计学意义(P<0.05)。结论根管治疗牙体牙髓病中应用iRoot SP冷侧法的充填效果和疗效与热牙胶垂直加压法基本相同,但iRoot SP冷侧法在减轻患者疼痛,改善咀嚼功能方面更具优势。

Caloric restriction-mimetics for the reduction of heart failure risk in aging heart: with consideration of gender-related differences

The literature is full of claims regarding the consumption of polyphenol or polyamine-rich foods that offer some protection from developing cardiovascular disease(CVD). This is achieved by preventing cardiac hypertrophy and protecting blood vessels through improving the function of endothelium. However, do these interventions work in the aged human hearts? Cardiac aging is accompanied by an increase in left ventricular hypertrophy, along with diastolic and systolic dysfunction. It also confers significant cardiovascular risks for both sexes. The incidence and prevalence of CVD increase sharply at an earlier age in men than women. Furthermore, the patterns of heart failure differ between sexes, as do the lifetime risk factors. Do caloric restriction(CR)-mimetics, rich in polyphenol or polyamine, delay or reverse cardiac aging equally in both men and women? This review will discuss three areas:(1) mechanisms underlying age-related cardiac remodeling;(2) gender-related differences and potential mechanisms underlying diminished cardiac response in older men and women;(3) we select a few polyphenol or polyamine rich compounds as the CRmimetics, such as resveratrol, quercetin, curcumin, epigallocatechin gallate and spermidine, due to their capability to extend health-span and induce autophagy. We outline their abilities and issues on retarding aging in animal hearts and preventing CVD in humans. We discuss the confounding factors that should be considered for developing therapeutic strategies against cardiac aging in humans.

Effects of Root Penetration Restriction on Growth and Mn Nutrition of Different Winter Wheat Genotypes in Paddy Soils

Effects of root penetration restriction on the growth and Mn nutrition of different wheat genotypes were studied in paddy soils using a method of nylon net bags (400 mesh) buried in the soil. The results showed that the spatial distribution of Mn in paddy soils played an important role in the growth and Mn nutrition of wheat crops. In the treatment where wheat roots were restricted in the plough layer by nylon net bags, the symptoms of Mn deficiency in wheat occurred much earlier and more seriously than usual. Of the two tested wheat genotypes, 80-8 was tolerant to Mn deficiency while 3295 was sensitive to Mn deficiency, respectively. The restriction of root penetration intensified symptoms of Mn deficiency of the Mn-deficient sensitive genotype (3295). The experiment demonstrated that well-developed roots with a strong ability to penetrate into the Mn-rich deep soil layer might explain the better tolerance of Mn deficiency in the tolerant genotypes.

The effect of caloric restriction on genetical pathways

Energy restriction is defined as reducing nutrient intake without dragging the organism into malnutrition. Energy restriction is preferred because it is a non-genetic intervention that increases life expectancy. Nicotinamide adenine dinucleotide(NAD~+)and adenosine monophosphate(AMP)levels, which are the indicators of intracellular energy deficiency, increase with energy restriction. The increase in NAD~+ level stimulates sirtuin(SIRT)enzymes, and the increase in AMP level stimulates AMP-activated protein kinase(AMPK). Various mechanisms are regulated by stimulating these enzymes. By Forkhead box O(FoxO)transcription factors, the ability of resistance to oxidative stress increases, and antioxidant genes, DNA repair, and autophagy genes are stimulated. Apoptosis is induced by stimulation of the p53 protein, and tumor growth is suppressed by the disruption of aging cells. The suppression of phosphoinositide 3-kinase(PI3K)-/-Akt, and therefore mTOR signal stimulates autophagy and mitophagia, and cleanses damaged cells and organelles. Mitochondrial biogenesis is stimulated, antioxidant capacity increases, and inflammatory response decreases. Adipose tissue and lipid metabolism are regulated by the regulation of fatty acid synthesis and oxidation. As a consequence, the effects of caloric restriction on cellular metabolism are regulated through the genetic pathways.

Dietary Vitamin K Restriction and Effectiveness of Vitamin K Antagonists Prescribed at the CNHU-HKM University Cardiology Clinic/BENIN

Introduction: Their efficacy in preventing thrombotic and embolic events has been proven in numerous studies, but their narrow therapeutic index requires particular vigilance, especially in terms of biology. In addition, treatment-related hemorrhagic complications are not uncommon. This study explores the influence of dietary vitamin K restriction on the efficacy of antivitamin K treatment at the University Cardiology Clinic of CNHU-HKM. Methods: Cross-sectional and descriptive study that took place from 25 April to 29 August 2019. Patients’ dietary behaviors and successive INR values were collected. Information on dietary intake was obtained by 2 non-consecutive 24-hour recalls. The effectiveness of VKA treatment was assessed by the “Time in Therapeutic Range” (TTR) of the INR. VKA treatment was considered effective for a TTR greater than 65%. Results: At the end of this study, 40 patients were surveyed. The mean age of the participants was 58.05 years ± 13.32 years, with a sex ratio of 1.35. Complete arrhythmia due to atrial fibrillation was the main indication for VKA treatment (37.50%) and fluindione was the most commonly prescribed drug (77.50%). The duration of treatment was less than or equal to 2 years in 47.5% of the subjects surveyed. Before starting treatment, 85% of patients received advice on restricting vitamin K-rich foods, and 45% of patients reported “food burnout” after a period of compliance with the restriction. The majority of respondents (97.50%) complied with the restriction on vitamin K-rich foods. All respondents had high energy intakes and a poor distribution of macronutrients, with a predominance of carbohydrates and proteins. 2.5% of respondents were on effective anti-vitamin K therapy with a TTR of over 65%. Conclusion: Restriction of vitamin K-rich foods is not conducive to effective treatment with vitamin K antagonists.

Calorie restriction potentiates epigallocatechin-3-gallate-mediated Nrf2 activation in hepatocytes of aged rats

Objective:To explore the combinatorial effect of epigallocatechin-3-gallate(EGCG)and calorie restriction on activation of nuclear factor erythroid 2-related factor 2(Nrf2),a transcription factor involved in the antioxidant defense system of aged rats.Methods:Aged male Wistar rats were calorie-restricted and treated with EGCG orally for 45 days.The initial body weight of aged rats was recorded,and the final body weight was measured at the end of the experimental period.Serum lipid and lipoprotein status,oxidative stress markers such as free radicals and malondialdehyde levels,and reduced glutathione were assessed.In addition,RT-PCR and Western blotting analyses were performed.Results:Calorie restriction potentiated the effect of EGCG on enhancing antioxidant status,improving the levels of serum lipid and lipoproteins,upregulating Nrf2 and Bcl2,and downregulating Keap1,cullin3,Bax and cytochrome c in aged rats.Conclusions:Calorie restriction can promote EGCG-mediated Nrf2 activation in aged rats.This preliminary finding paves the way for a combinatory approach to replenishing the antioxidant status during aging,thereby reducing the risk for age-associated degenerative diseases.

Effect of Sleep Hygiene Orientation on Social Cognition Impairments Due to Chronic Sleep Restriction in Mexican Medical Residents

Introduction: Sleep is critical to human physiological function, cognitive performance, and emotional regulation. Healthcare personnel, especially physicians, are chronically exposed to long working hours, which are often accompanied by decreased sleep time. Clinical evidence indicates that these conditions affect their cognitive function and professional practice, but researchers in the field have not sufficiently explored the possible effects of reductions in sleep time on social cognition. Objective: The aim of this is to further explore the effects of sleep restriction among medical residents, the specific impairments in social cognition that it produces, and the effects of a sleep hygiene orientation on those impairments. Method: There were 124 medical residents (50 males, 74 females) who completed a daily sleep/work log, a battery of sleep tests/questionnaires, and neuropsychological evaluations. The participants then received a short course (8 hours) on basic concepts of sleep hygiene and sleep psychoeducation. Once the course was completed, participants filled out the questionnaires again. Results: The results indicate that sleep disturbances in medical residents were associated with severe neurocognitive and social cognition impairments. After the sleep hygiene intervention, neuropsychological function and sleep parameters improved, awareness increased, and social cognition performance significantly improved. Conclusion: Using sleep psychoeducation and sleep hygiene intervention in medical residents is a simple strategy to mitigate the effects of sleep restriction.

Effects of root restriction on nitrogen and gene expression levels in nitrogen metabolism in Jumeigui grapevines(Vitis vinifera L.×Vitis labrusca L.)

To decipher the relationship between the inhibited shoot growth and expression pattern of key enzymes in nitrogen metabolism under root restriction, the effects of root restriction on diurnal variation of expression of nitrate reductase （NR）, nitrite reductase （NiR）, glutamine synthetase （GSI-1, GS1-2, GS2） and glutamate synthase （Fd-GOGAT, NADH-GOGAT） genes and nitrogen levels were evaluated in two-year-old Jumeigui grapevines （Vitis vinifera L.xVitis labrusca L.） when significant differences in shoot growth were observed between treatments at expansion stage （22 days after anthesis）. Grapevines were planted in root-restricting pits as root restriction and in an unrestricted field as the control. Results showed that root restriction significantly reduced shoot growth, but promoted the growth of white roots and fibrous brown roots and improved the fruit quality. （NO3-＋NO2-）-N concentration in all plant parts, NH4＋-N concentration in white roots and total N concentration in leaves and brown roots were significantly reduced under root restriction. Gene expression analysis revealed that mRNA levels of genes related to the GS1/NADH-GOGAT pathway were lower in root-restricted than in control petioles, whereas genes involved in the GS2/Fd-GOGAT pathway were up-regulated under root restriction. Root restriction also resulted in downregulation of genes involved in nitrogen metabolism in leaves, especially at 10：00, while transcript levels of all these genes were enhanced in root-restricted white and brown roots at most time points. This organ-dependent response contributed to the alteration in NO3- reduction and NH4＋ assimilation under root restriction, leading to less NO3- transported from roots and then assimilated in root-restricted leaves. Therefore, this study implied that shoot growth inhibition in grapevines under root restriction is closely associated with down-regulation of gene expression in nitrogen metabolism in leaves.

Involvement of the ABA-and H_(2)O_(2)-Mediated Ascorbate-Glutathione Cycle in the Drought Stress Responses of Wheat Roots

Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and the AsA–GSH cycle under drought stress in wheat has not been studied.In this study,a hydroponic experiment was conducted in wheat seedlings subjected to 15%polyethylene glycol(PEG)6000–induced dehydration.Drought stress caused the rapid accumulation of endogenous ABA and H_(2)O_(2) and significantly decreased the number of root tips compared with the control.The application of ABA significantly increased the number of root tips,whereas the application of H_(2)O_(2) markedly reduced the number of root tips,compared with that under 15%PEG-6000.In addition,drought stress markedly increased the DHA,GSH and GSSG levels,but decreased the AsA levels,AsA/DHA and GSH/GSSG ratios compared with those in the control.The activities of the four enzymes in the AsA–GSH cycle were also markedly increased under drought stress,including glutathione reductase(GR),ascorbate peroxidase(APX),monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR),compared with those in the control.However,the application of an ABA inhibitor significantly inhibited GR,DHAR and APX activities,whereas the application of an H_(2)O_(2) inhibitor significantly inhibited DHAR and MDHAR activities.Furthermore,the application of ABA inhibitor significantly promoted the increases of H_(2)O_(2) and the application of H_(2)O_(2) inhibitor significantly blocked the increases of ABA,compared with those under 15% PEG-6000.Taken together,the results indicated that ABA and H_(2)O_(2) probably interact under drought stress in wheat;and both of them can mediate drought stress by modulating the enzymes in AsA–GSH cycle,where ABA acts as the main regulator of GR,DHAR,and APX activities,and H_(2)O_(2) acts as the main regulator of DHAR and MDHAR activities.

Broad Hormonal Responses Induced by Aluminum in Roots of Dwarf Transgenics of Solanum lycopersicum L. cv “Micro-Tom”

The spatial pattern distribution of plant hormones in response to aluminum (Al) toxicity in roots remains to be shown. This study was performed to assess the root hormonal accumulation and gene expression in response to Al toxicity in five transgenic miniature dwarf tomatoes cv. Micro-Tom (MT). MT and MT transgenics to acid indole acetic, cytokinin, gibberellin, abscisic acid and ethylene were cultivated in nutrient solutions containing different Al concentrations. Root growth elongation was measured and cellular damage was visualized by staining Evans’s blue. The GUS reporter gene staining technique was used to visualize hormonal changes in MT apex root tissues. Data indicated that the MT is sensitive to Al that induced significant growth inhibition and cellular damage. Al concentration of 27 μM was significantly toxic, inducing root apex darkening and inhibition of root development. The qualitative evaluation of GUS reporter gene expression showed intense crosstalk among all hormones studied, underscoring the complexity of signaling induced by Al in apex roots. Results point out to a major understanding of the hormonal signaling in response to Al toxicity, which may induce a change of root growth and architecture with growth inhibition and cell constraints modulated by all different hormones evaluated.

Shear resistance characteristics and influencing factors of root-soil composite on an alpine metal mine dump slope with different recovery periods

Artificial vegetation restoration is the main measure for vegetation restoration and soil and water conservation in alpine mine dumps on the Qinghai-Tibet Plateau,China.However,there are few reports on the dynamic changes and the influencing factors of the soil reinforcement effect of plant species after artificial vegetation restoration under different recovery periods.We selected dump areas of the Delni Copper Mine in Qinghai Province,China to study the relationship between the shear strength and the peak displacement of the root-soil composite on the slope during the recovery period,and the influence of the root traits and soil physical properties on the shear resistance characteristics of the root-soil composite via in situ direct shear tests.The results indicate that the shear strength and peak displacement of the rooted soil initially decreased and then increased with the increase of the recovery period.The shear strength of the rooted soil and the recovery period exhibited a quadratic function relationship.There is no significant function relationship between the peak displacement and the recovery period.Significant positive correlations(P<0.05)exists between the shear strength of the root-soil composite and the root biomass density,root volume density,and root area ratio,and they show significant linear correlations(P<0.05).There are no significant correlations(P>0.05)between the shear strength of the root-soil composite and the root length density,and the root volume ratio of the coarse roots to the fine roots.A significant negative linear correlation(P<0.05)exists between the peak displacement of the rooted soil and the coarse-grain content,but no significant correlations(P>0.05)with the root traits,other soil physical property indices(the moisture content and dry density of the soil),and slope gradient.The coarse-grain content is the main factor controlling the peak displacement of the rooted soil.

Increasing root-lower characteristics improves drought tolerance in cotton cultivars at the seedling stage

Drought is an important abiotic stress factor in cotton production.The root system architecture(RSA)of cotton shows high plasticity which can alleviate drought-related stress under drought stress(DS)conditions;however,this alleviation is cultivar dependent.Therefore,this study estimated the genetic variability of RSA in cotton under DS.Using the paper-based growth system,we assessed the RSA variability in 80 cotton cultivars at the seedling stage,with 0 and10%polyethylene glycol 6000(PEG6000)as the control(CK)and DS treatment,respectively.An analysis of 23 aboveground and root traits in the 80 cotton cultivars revealed different responses to DS.On the 10th day after DS treatment,the degree of variation in the RSA traits under DS(5–55%)was greater than that of CK(5–49%).The 80 cultivars were divided into drought-tolerant cultivars(group 1),intermediate drought-tolerant cultivars(group 2),and drought-sensitive cultivars(group 3)based on their comprehensive evaluation values of drought resistance.Under DS,the root lengthlower,root area-lower,root volume-lower,and root length density-lower were significantly reduced by 63,71,76,and 4%in the drought-sensitive cultivars compared to CK.Notably,the drought-tolerant cultivars maintained their root lengthlower,root area-lower,root volume-lower,and root length density–lower attributes.Compared to CK,the root diameter(0–2 mm)-lower increased by 21%in group 1 but decreased by 3 and 64%in groups 2 and 3,respectively,under DS.Additionally,the drought-tolerant cultivars displayed a plastic response under DS that was characterized by an increase in the root-lower characteristics.Drought resistance was positively correlated with the root area-lower and root length density-lower.Overall,the RSA of the different cotton cultivars varied greatly under DS.Therefore,important root traits,such as the root-lower traits,provide great insights for exploring whether drought-tolerant cotton cultivars can effectively withstand adverse environments.

Cooperative UAV search strategy based on DMPC-AACO algorithm in restricted communication scenarios

Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research problem.In certain mission environments,due to the impact of many interference sources on real-time communication or mission requirements such as the need to implement communication regulations,the mission stages are represented as a dynamic combination of several communication-available and communication-unavailable stages.Furthermore,the data interaction between unmanned aerial vehicles(UAVs)can only be performed in specific communication-available stages.Traditional cooperative search algorithms cannot handle such situations well.To solve this problem,this study constructed a distributed model predictive control(DMPC)architecture for a collaborative control of UAVs and used the Voronoi diagram generation method to re-plan the search areas of all UAVs in real time to avoid repetition of search areas and UAV collisions while improving the search efficiency and safety factor.An attention mechanism ant-colony optimization(AACO)algorithm is proposed for UAV search-control decision planning.The search strategy is adaptively updated by introducing an attention mechanism for regular instruction information,a priori information,and emergent information of the mission to satisfy different search expectations to the maximum extent.Simulation results show that the proposed algorithm achieves better search performance than traditional algorithms in restricted communication constraint scenarios.