SR Treatment Research Articles

Effect of strontium on nutrient uptake, physiological parameters, and strontium localization in lettuce.

Human activities increase the risk of stable and radioactive strontium (Sr) isotopes entering the environment and food chain. In this study, the effects of Sr on the nutrient uptake and physiological responses of lettuce under different "Sr treatment" concentrations (0, control, 1, 2, 3, 4, and 5mM) and "times" (7, 14, and 21day) were studied in a hydroponic system. In addition, the distribution of Sr on the surfaces and cross-sections of lettuce leaves was revealed by scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis. A two-way analysis of variance (ANOVA) method was used to analyze the significance of "Sr treatment," "time," and their "interaction." The results showed that an increase in Sr uptake in lettuce could significantly reduce the uptake of calcium (Ca). The contents of sulfur (S), potassium (K), and iron (Fe) in lettuce leaves showed significant differences with the sampling day. Similarly, the fresh weight of lettuce leaves and roots as well as the photosynthetic pigment contents of lettuce leaves was also significantly different with the sampling day. The activities of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD)) showed significant differences with the sampling day. The activities of SOD and CAT decreased significantly with the sampling day, while POD increased significantly. The MDA content increased significantly with increasing hydroponic Sr concentration on the 21st day. SEM-EDX analysis showed that the weight percentage of Sr in the vascular bundle sheath in the cross-section of lettuce leaves was relatively higher than that in the mesophyll. This study aids our understanding of the distribution of Sr in lettuce leaf tissues and the effect of Sr on lettuce physiology.

Mechanical thrombectomy injury to the arterial wall: A comparison between catheter aspiration and stent retriever

PurposeTo compare the extent of arterial wall damage when SR and CA were used for treatment of AIS models to evaluate their efficacy and safety. MethodsA thrombin-induced thrombus was pre-injected into the right distal external carotid-maxillary artery (ECMA) in 12 dogs to create an acute thrombus occlusion model and were randomly divided into the SR group (n = 6; received SR treatment) and CA group (n = 6; received CA treatment). Device safety was also assessed by five passages through the normal left ECMA using each device. Device manipulation-related damage to arterial walls, final flow restoration, recanalization time and complications were recorded. ResultsSixteen retriever and 10 aspiration attempts were performed in the SR and CA groups. Reperfusion time was significantly reduced in the CA group (17.83 ± 1.96 vs. 28.33 ± 3.26 in the SR group; P = 0.02). Stent retriever thrombectomy resulted in an increased risk of endothelium denudation (1.17 ± 0.24 in SR group vs. 0.42 ± 0.15 in CA group; P = 0.01) and reduced frequency of vessel vasospasm (0.67 ± 0.14 in SR group vs. 0.25 ± 0.13 in CA group; P = 0.04). Injury score and thrombus deposition were similar between the two groups (P > 0.05). TICI 2b/3 flow restoration values of the right ECMA were 100 % in both groups. Device-related complications, including dissection (P = 0.21), side branch influence (P = 0.24), and distal thromboembolism (P = 1.00), did not differ between the two groups. ConclusionBoth devices had similar efficacy and caused minimal arterial wall damage in our dog models. SR was more likely to cause endothelium denudation, while CA had a greater risk of vasospasm.

Effects of Vegetation Restoration on the Structure and Function of the Rhizosphere Soil Bacterial Community of Solanum rostratum

Invasive plants can change soil microbial communities and therefore promote invasion. While vegetation restoration has been adopted in certain infested lands to curb the invasion of Solanum rostratum, changes in the composition and function of rhizosphere soil bacterial communities of the species before and after the restoration has not yet been reported. In this study, two vegetation combinations used in previous studies were selected as candidates:Astragalus adsurgens+Elymus dahuricus+Bromus inermis (T1) and A. adsurgens+Festuca arundinacea+Agropyron cristatum+Leymus chinensis (T2). Rhizosphere soil samples were collected from each combination (T1 and T2), a S. rostratum invaded area (SR), and the native plant (NP) control to analyze the bacterial community structure and diversity using 16S rDNA gene sequencing on the Illumina MiSeq platform. PICRUSt was further used to predict the functional abilities of soil bacterial communities. Results of 16S rDNA gene sequencing showed that both the Simpson and Chao1 indices were higher in the SR treatment than in the NP treatment, but neither reached a significant level, although both indices decreased significantly after vegetation restoration (T1 and T2; P<0.05). The relative abundance of Microvirga, Skermanella, and Sphingomonas from phylum Proteobacteria and Bryobacter from the phylum Acidobacteria were significantly lower in the SR treatment (P<0.05) when compared with the NP treatment and higher in restoration treatments (T1 and T2). The RDA analysis showed that soil organic matter (OM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), and available potassium (AK) were important factors affecting the composition of the bacterial community. Based on the PICRUSt analysis of soil bacterial community functions, the relative abundance of gene families related to biosynthesis of amino acids, purine metabolism, pyrimidine metabolism, ribosome, and aminoacyl-tRNA biosynthesis were higher in the rhizosphere samples of the SR treatment than those of the NP treatment and reduced significantly after vegetation restoration (T1 and T2; P<0.05). The structure and function of rhizosphere soil bacterial community of S. rostratum and vegetation restoration were analyzed and provided a theoretical basis for the invasion mechanism and ecological restoration of S. rostratum.

Lactating dairy cows managed for second and greater artificial insemination services with the Short-Resynch or Day 25 Resynch program had similar reproductive performance

The objective of this randomized controlled experiment was to evaluate reproductive performance and reproductive physiological outcomes of lactating Holstein cows managed for second and greater artificial insemination (AI) services with the Short-Resynch or Day 25 Resynch program. Cows from 2 commercial farms were randomly assigned after first service to the Short-Resynch (SR; n = 870) or Day 25 Resynch (D25R; n = 917) program in which they remained until 210 d after first service or left the herd. Cows in D25R received GnRH 25 ± 3 d after AI, whereas cows in SR did not. Cows not reinseminated at detected estrus (AIE) by 32 ± 3 d after AI underwent nonpregnancy diagnosis (NPD) through transrectal ultrasonography (TUS). Nonpregnant cows from both treatments with a corpus luteum (CL) ≥15 mm and an ovarian follicle ≥10 mm (hereafter, CL cows) received 2 PGF2α treatments 24 h apart, GnRH 32 h after the second PGF2α, and timed AI 16 to 18 h later. Cows that did not meet the criteria to be included in the CL group (NoCL cows) received a modified Ovsynch protocol with progesterone (P4) supplementation [P4-Ovsynch; GnRH and controlled internal drug-release device (CIDR) in, 7 d later CIDR removal and PGF2α, 24 h later PGF2α, 32 h later GnRH, and 16 to 18 h later timed AI]. In a subgroup of cows, blood samples were collected and TUS conducted at each treatment to evaluate ovarian responses to resynchronization. Binary data were analyzed with logistic regression, continuous data by ANOVA, and time-to-event data by Cox's proportional hazard regression. A greater proportion (mean; 95% CI) of cows were AIE before NPD in the SR (60.5%; 57.0-63.8; n = 3,416) than the D25R (50.1%; 46.5-53.7; n = 3,177) treatment, whereas pregnancy per AI (P/AI) at 32 d for AIE services before NPD was greater for the D25R (41.3%; 38.8-43.8; n = 1,560) than the SR (37.6%; 35.5-39.8; n = 1,961) treatment. At NPD, a greater proportion of cows in the D25R (84.3%; 82.2-86.2) than the SR (77.0%; 74.4-79.4) treatment were considered CL cows. Pregnancy per AI at 32 d was greater for the D25R than the SR treatment for all timed AI services (D25R = 43.0%; 40.2-45.9 vs. SR = 36.8%; 33.8-39.8) and for CL cows (D25R = 42.8%; 39.7-45.9 vs. SR = 33.8%; 30.6-37.2) but did not differ for NoCL cows (D25R = 39.4%; 32.1-47.3 vs. SR = 44.0%; 36.8-51.4). The hazard ratio for time to pregnancy (1.03; 0.93-1.14) and the proportion of cows not pregnant at the end of the observation period (D25R = 5.9%; 4.4-7.8 vs. SR = 6.7%; 5.0-8.7) did not differ between SR and D25R treatments. The GnRH treatment 25 d after AI resulted in more cows with P4 >1 ng/mL (D25R = 80.5%; 75.3-84.9 vs. SR = 63.6%; 57.3-69.4) and smaller follicle diameter at NPD 32 ± 3 d after AI for D25R (16.2 ± 0.4 mm) than for SR (17.5 ± 0.4 mm); however, it did not affect follicle diameter and luteal regression risk (CL cows only) before TAI. We concluded that the use of reproductive management programs including SR and D25R for CL cows and the P4-Ovsynch protocol for NoCL cows resulted in similar hazard of pregnancy and proportion of nonpregnant cows for up to 210 d after first service.

The impact of a yoga-based physical therapy group for individuals with traumatic brain injury: results from a pilot study

ABSTRACT Objective To compare the impacts of yoga-based physical therapy versus a seated rest within the context of standard rehabilitation practice on sleep, heart rate variability (HRV), anxiety, and fatigue during acute traumatic brain injury (TBI) rehabilitation. Methods Eleven individuals participated in this crossover study involving the following interventions in a randomized order: group yoga-based physical therapy (YPT), conventional physical therapy (CPT), and group seated rest in a relaxing environment (SR). HRV and self-reported anxiety and fatigue were measured immediately before and after each group, and sleep after each condition and at baseline. Data was analyzed using generalized linear mixed models with repeated measures. Results The interaction between time and treatment was statistically significant (p = .0203). For the SR treatment, wake after sleep onset (WASO) rate was reduced from 14.99 to 10.60 (IRR = 0.71; p = .006). Time and treatment were not found to be statistically significantly associated with any of the secondary outcomes. Conclusion Yoga-based physical therapy is feasible and safe in the inpatient rehabilitation setting following TBI. Sleep quality improved following the addition of a one-hour seated rest in a relaxing environment to a standard rehabilitation daily schedule, suggesting that structured rest time may be beneficial to sleep hygiene during inpatient rehabilitation following TBI. ClinicalTrials.Gov Registration Number: NCT03701594

Strontium Uptake and Effects in Hydroponically Cultivated Celery

The artificial radionuclide 90Sr is the main radionuclide in radioactive environmental pollution. In this study, celery was cultured in a laboratory hydroponics system for 21 days with strontium (Sr) levels of 0 (control), 0.5, 1, 2.5, 5, and 10 mM. The changes in the Sr contents in celery leaves and roots as well as the translocation factor (TF) values (ratio of the Sr concentration in aerial plant parts to that in roots) under different Sr concentrations were studied. Additionally, the effects of Sr stress on the absorption of six nutrients, the chlorophyll content, and the biomass of the celery were investigated. The results showed that the Sr contents in celery leaves and roots increased with the increasing Sr concentration in the hydroponic solution, but the increase of the Sr concentration in roots slowed under the 10 mM Sr treatment. The mean TF values ranged from 0.40 ± 0.01 to 1.12 ± 0.17. With the increase in Sr concentration in the hydroponic medium, the contents of calcium, iron, and potassium in the celery leaves were significantly reduced, and the absorption of calcium, iron, and magnesium by roots was significantly inhibited. Compared with the control, sulfur concentration in celery roots increased significantly under the Sr treatments increasing except the 10 mM Sr treatment. The changes in chlorophyll content were consistent with those of celery biomass, and the values of both these parameters were high under the 5 mM Sr treatment.

Effects of sugarcane residue biochar and P fertilizer on P availability and its fractions in a calcareous clay loam soil

Biochar has the potential to affect the cycle of phosphorus (P), but the underlying mechanisms of its effects remain poorly understood in calcareous soils. Our understanding of the effects of biochar is limited in calcareous soils during incubation. Therefore, this study was conducted to investigate how the availability and mineral fractions of P change after the addition of combined biochar and P fertilizer during incubation in calcareous soil. Sugarcane residue (raw SR) and biochar (400 °C for 2 h) were added to soils treated with 50 mg kg−1 of P, in the form of Ca(H2PO4)2·H2O, at 0.5 and 1% (w/w). The soils were incubated at 25 ± 1 °C for 120 days. Available P (Olsen P) contents and mineral P fractions were measured after various incubation times (7, 30, 90, and 120 days). Biochar addition remarkably increased the amount of available P when compared with the raw SR treatment and the control condition (P < 0.05). After 30 days of incubation, the amount of available P in the soils decreased and remained unchanged thereafter. The results indicated that the addition of 50 mg kg−1 of P as fertilizer significantly augmented the labile P and P associated with Fe and Al in all the treatments at all incubation times (P < 0.05). In comparison with P treated with raw SR, P associated with Fe and Al was significantly enhanced after biochar addition (P < 0.05). Significant correlations were found for available P with labile P and P associated with Fe and Al. We found that biochar addition could increase available pools, thus improving available P concentrations at various incubation times. Therefore, we conclude that sugarcane residue biochar can enhance the available P in calcareous soils.

NMR and Mass Spectroscopy Based Comparison of Blood Metabolites from Dantrolene and SR59230A Treated Arctic Ground Squirrels

Arctic ground squirrels (AGS) hibernate during winter, undergoing cycles of torpor, where body temperatures plummet as low as −3°C followed by rapid rewarming to 37°C during interbout arousals (IBA). While IBAs only occur in certain species that experience torpor, they offer a unique model into which one can observe the specific mechanisms responsible for thermogenesis. Rapid rewarming at IBA onset increases AGS body temperature above 15°C through the activation of brown adipose tissue (BAT). Above 15°C, shivering thermogenesis is able to contribute to warming back up to original body temperature. However, the relative contributions of these two thermogenic processes during IBA is not well understood. AGS were treated across periods of coupled torpor cycles, whereby during the second cycle AGS were treated with either carrier (control) or a selected inhibitor. BAT inhibition using SR59230A, a β3‐adrenergic receptor inhibitor, would be expected to strain the rapid heat production. Shivering thermogenesis utilizes calcium cycling and the Ryanodine receptor in skeletal muscles; the use of dantrolene reduces the thermogenic mechanism needed to reach 37°, effectively inhibiting the Ryanodine receptor in muscle. Relative concentrations of blood plasma metabolites were quantified using nuclear magnetic resonance (NMR) to compare whole and polar extracted plasma. The NMR method was compared against full metabolomic analysis performed using liquid chromatography tandem mass spectroscopy (LC MS‐MS). NMR analysis resulted in higher peak resolution quality and increased metabolite identification in polar and lipid extraction samples compared to whole samples, whereas LC MS‐MS provided a greater abundance of metabolites. Overall, total metabolites were significantly reduced during hibernation. Dantrolene treated AGS had alterations in metabolites indicative of increased energy demand. Furthermore, SR treatment resulted in profiles describing decreased beta‐oxidation and generally lower total metabolites compared to Dantrolene. These trends indicate that changes in calcium cycling and BAT stimulation during hibernation can have profound effects on the animals ability to efficiently balance energy usage.Support or Funding InformationResearch reported in this publication was supported by an Institutional Development Award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20GM103395. The content is solely the responsibility of the authors and does not necessarily reflect the official views of the NIH. BLaST is supported by the NIH with the linked awards; TL4GM118992, RL5GM118990, UL1GM118991.

THE CHANGE IN STRUCTURE OF CLAY MINERALS AND ELUTION OF CS AND SR BY HEAT TREATMENT

THE CHANGE IN STRUCTURE OF CLAY MINERALS AND ELUTION OF CS AND SR BY HEAT TREATMENT

Strontium uptake and antioxidant capacity comparisons of low accumulator and high accumulator oat (Avena sativa L.) genotypes

The main object of the present study is to investigate genotypic differences in strontium (Sr) resistance of two oat varieties, including Neimengkeyi-1 (high accumulator) and Bayou-3 (low accumulator). The growth and antioxidant enzyme responses to five Sr concentrations (0, 25, 100, 500, and 1000 mg kg−1) were compared after 30-day Sr treatment. The shoot–Sr concentrations of Neimengkeyi-1 were higher than those of Bayou-3 in all treatments. The translocation factors of Neimengkeyi-1 in all treatments were greater than 1 and significantly higher than those of Bayou-3. Sr ions did not affect the growth of Neimengkeyi-1. The H2O2 contents and the leaf malondialdehyde contents of Neimengkeyi-1 were lower than those of Bayou-3. The activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase of Neimengkeyi-1 were significantly higher than those of Bayou-3. Significant negative correlations were found between H2O2 contents and SOD and CAT activities in Neimengkeyi-1. The results of this study suggest that Sr accumulation patterns have significant genotypic differences, and SOD and CAT may play a pivotal role in the detoxification mechanism of Sr.

Strontium Uptake and Effect in Lettuce and Radish Cultivated Under Hydroponic Conditions.

The accumulation of strontium (Sr) in lettuce and radish under 0 (control), 0.5, 1, 2.5, 5, and 10mM Sr treatments in hydroponic solution at 16, 23 and 30days and the effects of Sr stress on six nutrient elements in plants were investigated. The results showed that Sr concentrations in plant aerial and underground parts increased in low-Sr treatments (0.5, 1 and 2.5mM) and fluctuated in high-Sr treatments (5 and 10mM) throughout the three sampling periods. Sr concentrations were higher in roots than in leaves, reaching 108.8 ± 14.7 and 134.1 ± 1.2mg/g in lettuce and radish roots, respectively, after 10mM Sr treatment. Translocation factor (TF) values (ratio of the Sr concentrations in aerial parts to that in roots) were inversely related to the Sr content in the hydroponic solution, and reached 1.45 ± 0.17 to 0.15 ± 0.03 and 1.06 ± 0.20 to 0.12 ± 0.004 for lettuce and radish. The variation in chlorophyll content was consistent with that in plant biomass.

Influence of Strontium on Vascular Endothelial Growth Factor and Fibroblast Growth Factor 2 Expression in Rat Chondrocytes Cultured In Vitro.

Strontium (Sr) can reduce cartilage degeneration and stimulate cartilage matrix formation. Angiogenesis plays a developmental role in chondrogenesis, and was stimulated by growth factors such as vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF2). However, the direct influence of Sr on VEGF and FGF2 expressions in chondrocytes is not entirely clear. The objective of this study was to investigate the effects of different Sr concentrations on VEGF and FGF2 expressions in rat chondrocytes in vitro. Chondrocytes were isolated from Wistar rat articular by enzymatic digestion. As a Sr source, strontium chloride hexahydrate (SrCl2·6H2O) was added to the culture solution at final concentrations of 0, 0.5, 1.0, 2.0, 5.0, 20.0, and 100.0μg/mL. After 72h of continuous culture, mRNA abundance and protein expression levels of VEGF and FGF2 in the chondrocytes were determined by real-time polymerase chain reaction (real-time PCR) and Western blot, respectively. The results showed that VEGF and FGF2 expressions were dose-dependently elevated with Sr concentration in chondrocytes. The mRNA abundance and protein expression levels of VEGF were extremely significantly higher than those in the control group (P < 0.01) at 1.0μg/mL Sr treatment. For FGF2, there were markedly significant differences in mRNA and protein expression from control group (P < 0.01) when the Sr-treated concentration exceeded 5.0μg/mL and 20.0μg/mL, respectively. These results indicated that Sr might involve in the cartilage angiogenesis via regulating expression of VEGF and FGF2z.

Biomineralization of strontium and barium contributes to detoxification in the freshwater alga Micrasterias

The unicellular model alga Micrasterias denticulata inhabits acid peat bogs that are highly endangered by pollutants due to their high humidity. As it was known from earlier studies that algae like Micrasterias are capable of storing barium naturally in form of BaSO4 crystals, it was interesting to experimentally investigate distribution and sequestration of barium and the chemically similar alkaline earth metal strontium. Additionally, we intended to analyze whether biomineralization by crystal formation contributes to diminution of the generally toxic effects of these minerals to physiology and structure of this alga which is closely related to higher plants.The results show that depending on the treatment differently shaped crystals are formed in BaCl2 and Cl2Sr exposed Micrasterias cells. Modern microscopic techniques such as analytical TEM by electron energy loss spectroscopy and Raman microscopy provide evidence for the chemical composition of these crystals. It is shown that barium treatment results in the formation of insoluble BaSO4 crystals that develop within distinct compartments. During strontium exposure long rod-like crystals are formed and are surrounded by membranes. Based on the Raman signature of these crystals their composition is attributed to strontium citrate. These crystals are instable and are dissolved during cell death. During strontium as well as barium treatment cell division rates and photosynthetic oxygen production decreased in dependence of the concentration, whereas cell vitality was reduced only slightly. Together with the fact that TEM analyses revealed only minor ultrastructural alterations as consequence of relatively high concentrated BaCl2 and Cl2Sr exposure, this indicates that biomineralization of Sr and Ba protects the cells from severe damage or cell death at least within a particular concentration range and time period. In the case of Sr treatment where ROS levels were found to be elevated, hallmarks for autophagy of single organelles were observed by TEM, indicating beginning degradation processes.

Response of Maize Root Growth to Residue Management Strategies

Core Ideas Efficient use of crop residues can improve circular economy in agro‐ecosystems.Amount of stover to the field explained the variation in root length density and root dry weight density in double cropping of winter wheat and summer maize.Returning stover increased the yield of summer maize.Root characteristics and the yield of summer maize improved by returning stover. A 5‐yr experiment was conducted to explore the effects of returning various amounts of stover to the field on root characteristics and yield in a wheat (Triticum aestivum L.) and maize (Zea mays L.) double‐cropping system. The experiment was designed as a randomized block design with three replications for three treatments: based on all stalks of winter wheat returned to the field (i) all summer maize stalks were mechanically pulverized and returned to the field (SR); (ii) half of the summer maize stalks were mechanically pulverized and returned to the field (1/2 SR); and (iii) all summer maize stalks were fully removed (CK). Results indicated that, in the SR treatment, root fresh weight (RFW) and root dry weight (RDW) were 19.4 and 18.5% higher, respectively, compared with the CK treatment. Root length density (RLD), root surface area density (RSAD) were 13.7 and 29.4% higher in the SR treatment, compared with the CK treatment. The yield of summer maize was 15.1 and 17.1% higher in the SR and 1/2 SR treatments, respectively, compared with the CK treatment. Furthermore, RLD, RSAD, root dry weight density (RDWD), and root length in the 1/2 SR treatment were significantly higher than those in the SR treatment. These results indicated that moderate amounts of straw returned to the field had the greatest effect on root growth and development of maize. This work provides a theoretical basis for optimizing crop yield and the use of straw resources.

흰쥐의 피부상처 동물모델에서 苦蔘이 신생혈관형성에 미치는 영향

Wound healing is the restoration in injured skin tissue and one of the most important therapeutic targets. The process consists of inflammation, proliferation, and remodeling. There have been reported multiple factors that accelerate and delay wound healing. In this study we tested the hypothesis that Sophorae Radix extract would improve the recovery of wound healing after full-thickness skin wound in rats. Twenty young male Sprague-Dawley rats were used for the studies. A full-thickness skin wound was made on the dorsal skin of the rats. Either Sophorae Radix water extract (SR) or saline (Control) was orally administrated every day. The wound area was measured and the percentages of wound contraction, wound healed and wound epithelization were evaluated. After 15 days, the skin tissues were excised and examined by histopathological and immunohistochemistrical method. In results, wound area in SR group was significantly decreased to compared with Control. SR group showed the significant enhancements in the percentages of wound contraction, wound healed and wound epithelization. Histopathological examination revealed that SR induces neo-vascularization potential in wound healing process. SR treatment in rats significantly accelerated cutaneous wound healing in the angiogenesis process by increasing VEGF and TGF-β1 synthesis. These results suggest that Sophorae Radix enhance skin wound repair by increasing the angiogenic agents such as VEGF and TGF-β1.

A resynchronization of ovulation program based on ovarian structures present at nonpregnancy diagnosis reduced time to pregnancy in lactating dairy cows

Our objective was to evaluate time to pregnancy after the first service postpartum and pregnancy per artificial insemination (P/AI) in dairy cows managed with 2 resynchronization of ovulation programs. After first service, lactating Holstein cows were blocked by parity (primiparous vs. multiparous) and randomly assigned to the d 32 Resynch (R32; n = 1,010) or short Resynch (SR; n = 1,000) treatments. Nonpregnancy diagnosis (NPD) was conducted 32 ± 3 d after AI by transrectal ultrasonography. Nonpregnant cows in R32 received the Ovsynch protocol: GnRH, PGF2α 7 d later, GnRH 56 h later, and timed AI (TAI) 16 to 18 h later. Cows in SR with a corpus luteum (CL) ≥15 mm and a follicle ≥10 mm at NPD received PGF2α, PGF2α 24 h later, GnRH 32 h later, and TAI 16 to 18 h later. Cows in SR without a CL ≥15 mm or a follicle ≥10 mm at NPD received a modified Ovsynch protocol with 2 PGF2α treatments and progesterone (P4) supplementation (GnRH plus CIDR, PGF2α and CIDR removal 7 d later, PGF2α 24 h later, GnRH 32 h later, and TAI 16 to 18 h later). Blood samples were collected from a subgroup of cows at the GnRH before TAI (R32 = 114; SR = 121) to measure P4 concentration. Binomial outcomes were analyzed with logistic regression and hazard of pregnancy (R32 = 485; SR = 462) with Cox's proportional regression in SAS (SAS Institute, Cary, NC). For P/AI analysis, the TAI service was the experimental unit (R32 = 720; SR = 819). Models included treatment and parity as fixed effects and farm as random effect. The hazard of pregnancy was greater for the SR treatment (hazard ratio = 1.18; 95% confidence interval: 1.01-1.37). Median time to pregnancy was 95 and 79 d for the R32 and SR treatments, respectively. At NPD, 71.3 and 71.2% of cows had a CL for the R32 and SR treatments, respectively. Treatment did not affect overall P/AI 32 ± 3 d after AI (R32 = 31.0% vs. SR = 33.9%) or for cows with a CL at NPD (R32 = 32.7% vs. SR = 32.8%). For cows with no CL at NPD, P/AI was greater for the SR treatment (36.9%) than for the R32 treatment (28.6%). Pregnancy loss from 32 to 63 d after AI was similar for all services combined (R32 = 8.3% vs. SR = 10.4%) and for cows with no CL at NPD (R32 = 13.2% vs. SR = 7.2%) but tended to be affected by treatment for cows with a CL at NPD (R32 = 6.8% vs. SR = 11.9%). Treatment affected the proportion of cows with P4 ≤0.5 ng/mL at the GnRH before TAI for all cows (R32 = 68.4% vs. SR = 81.8%), tended to have an effect among cows with a CL (R32 = 70.0% vs. SR = 81.8%), and had no effect for cows with no CL (R32 = 64.7% vs. SR = 81.8%). We concluded that the SR program reduced time to pregnancy because of a reduction of the interbreeding interval for cows with a CL at NPD and greater P/AI in cows with no CL at NPD.

Antihyperglycemic and Antihyperlipidemic Activity of Hydroponic Stevia rebaudiana Aqueous Extract in Hyperglycemia Induced by Immobilization Stress in Rabbits.

Diabetes mellitus (DM) is a serious worldwide problem related to human hyperglycemia. Thus, herbal preparations with antihyperglycemic properties especially leaf extracts of hydroponic Stevia rebaudiana (SR) would be useful in hyperglycemia treatment. The antihyperglycemic potential of this medicinal plant grown using hydroponics methods has been evaluated. Significant reduction of some biochemical characteristics for sugars and fatty acids in blood, liver, and muscle especially fasting glucose levels, serum triglycerides, LDL-cholesterol, total cholesterol levels, and increased HDL-cholesterol ones was shown with SR aqueous extract treatment. Therefore, the aqueous extract of SR is suggested to have antihyperglycemic and antihyperlipidemic activity and to restore liver and muscle glycogen levels (hepatoprotective effects) in hyperglycemia induced by immobilization stress in rabbits and might be recommended for treatment of DM (hyperglycemia).

Strontium (Sr) elicits odontogenic differentiation of human dental pulp stem cells (hDPSCs): A therapeutic role for Sr in dentine repair?

Strontium (Sr) forms a significant component of dental restorative materials and although it is widely used in toothpastes, the biological effects of Sr on the dentine-pulp complex have not been investigated. In this first study, we characterise the Sr elicited effects on human dental pulp stem cells (hDPSC) in vitro using exogenously Sr added to culture medium, and bioavailable Sr derived from a novel bioactive glass (BG). The related mechanisms were also investigated. Our results indicate that low dose Sr (between 0.1 and 2.5mM) induces proliferation and alkaline phosphatase (ALP) activity of hDPSCs, but has no effect on colony formation or cell migration. Sr at specific concentrations (1 and 2.5mM) stimulated collagen formation and mineralisation of the hDPSC generated matrix. In addition, qRT-PCR, Western blotting and immunocytochemistry revealed that Sr regulates gene expression and the protein secretion of the odontogenic markers: dentine sialophosphoprotein (DSPP) and dentine matrix protein 1 (DMP-1) and protein localisation (DSPP was localised to the Golgi, while no apparent changes occur in DMP-1 distribution which remains in both cytosol and the nucleus). Additionally, the calcium sensing receptor (CaSR) and downstream pathway MAPK/ERK signalling pathway in hDPSCs were activated by Sr. Bioavailable Sr from the BG revealed novel biological insights of regulating metabolic and ALP activities in hDPSCs. Taken together, these results suggest that Sr at specific doses significantly influences proliferation, odontogenic differentiation and mineralisation of hDPSCs in vitro via the CaSR using a pathway with similarities to osteoblast differentiation. These are the first such studies and indicate that Sr treatment of hDPSCs could be a promising therapeutic agent in dental applications. In conclusion, we propose that Sr from a substituted BG could be used more effectively in biomaterials designed for dental applications. Statement of SignificanceDespite the fact that strontium (Sr) is used widely in dental practise, its potential effects on odontoblasts have been ignored. Our study provides the first evidence that Sr (exogenous and that derived from a bioglass (BG)) can stimulate dentinogenesis in human dental pulp stem cells (hDPSCs) by promoting their proliferation, differentiation and mineralisation in vitro. Therefore, while previously unrecognised, Sr BG is likely to be beneficial in atraumatic dentistry practise and maintenance of a competent tooth in conditions such as caries. Repair of defected dentine is still one of the main challenges in dental research and annually untreated caries results in the loss of productivity equivalent to US$ 27 billion. Advances in tissue engineering technology, alongside the use of dental pulp stem cells provide an approach to achieve dentine regeneration. Understanding the actions of Sr will permit a more controlled application of Sr in the clinic. These data are thus likely to be of great interest to the material scientists, biological researchers, clinicians and manufacturers of dental products.

Winter wheat grain yield, water use, biomass accumulation and remobilisation under tillage in the North China Plain

We conducted a two-year experiment (2007–2009) in the North China Plain with supplemental irrigation to investigate the effects of tillage practices on the water use, biomass accumulation and remobilisation of winter wheat. Five tillage treatments were tested: strip rotary tillage (SR), rotary tillage (R), mouldboard ploughing (P), strip rotary tillage after subsoiling (SRS) and rotary tillage after subsoiling (RS). SRS significantly promoted the changes in soil water storage (ΔS) at soil depths of 60cm to 160cm, and the lowest ΔS level was observed in the SR treatment. The 60cm to 140cm soil moisture content in the SRS treatment was higher by 10.84% than that of the SR treatment before sowing in 2008–2009 and lower by 14.85% at maturity. The lowest dry matter remobilisation during grain filling (DMR) was detected in the SRS treatment. This value was 22.22% and 30.27% lower than those of the SR treatment in 2007–2008 and 2008–2009, respectively. However, the SRS treatment exhibited the highest contribution of dry matter accumulation during grain filling (CDMRG), in which high flag leaf photosynthetic rate (Pn) was observed from anthesis to maturity. The SRS and RS treatments exhibited the highest grain yields (9237.20 and 9261.31kgha−1 for two-year average) with no significant difference between the two treatments. The highest grain yields for the two treatments were 10.76% and 11.05% higher than those of the P treatment, correspondingly. The average water-use efficiency (WUE) for the two growing seasons was 20.49kgha−1mm−1 in the SRS treatment, which was higher than those in the SR, R, P and RS treatments by 17.02%, 13.42%, 8.73% and 3.83%, respectively. Hence, SRS would be a preferable tillage system for planting wheat in this region.

The Effect of Addition of Ce and Sr on the Solidification Path of Al–8Si–2Cu Alloy

Thermal analysis of Al–Si alloys is very useful for the non-destructive evaluation of the melt quality. The present work aimed at the study of the effect of addition of Ce and Sr on cooling curve parameters, microstructure and mechanical properties of Al–8Si–2Cu alloy. The thermal analysis parameters of melt treated alloys were determined. The addition of Ce influenced both primary and eutectic phase nucleation temperatures, whereas, Sr affected only the eutectic nucleation temperature. The depression in the eutectic arrest temperature was higher with Sr addition when compared to Ce. Consequently, a high degree of modification was achieved with Sr. The addition of Ce yielded fine equiaxed α-aluminium grains and Sr treatment resulted in columnar grains. The mechanical properties of the alloy significantly improved on simultaneous addition of Ce and Sr. The individual addition of Sr, Ce and combined addition of Ce + Sr to base alloy increased the tensile strength by about 40, 52 and 83 % respectively.