•Superhydrophobic surface was prepared by MAO with subsequent hydrophobization.•The water contact angle of the superhydrophobic Ti-6Al-4V alloy was 153.39°.•The corrosion resistance of the ...superhydrophobic sample increased by 10 times.•The hemocompatibility of the superhydrophobic sample was greatly improved.
In this paper the micro-arc oxidation (MAO) technique and subsequent superhydrophobic treatment were applied to fabricate the superhydrophobic TiO2 coatings on biomedical Ti-6Al-4V alloys. The surface morphology, surface roughness, water contact angle, corrosion resistance and hemocompatibility of the MAO and superhydrophobic samples were investigated. The results showed that the single anatase TiO2 coating was formed on the surface Ti-6Al-4V alloy with rough and porous micrometer-scale structure. The low surface energy film was grafted on the surface of the TiO2 coating by self-assembling reaction during the hydrophobic treatment process, which resulted in the formation of superhydrophobic surfaces with the water contact angle of 153.39°. It was found that the corrosion resistance of the superhydrophobic samples increased by one order of magnitude compared to those of the uncoated Ti-6Al-4V alloys. The hemolysis ratio and platelets adhesion characteristics of the Ti-6Al-4V alloys were also improved greatly through the MAO treatment and subsequent superhydrophobic treatment. Especially, no platelet could be observed on the surface of the superhydrophobic samples. Therefore, the superhydrophobic TiO2 coatings of Ti-6Al-4V alloys with higher hemocompatibility would show great promise in their potential blood-contacting applications.
Aim To explore the relationship between extracellular volume (ECV), native T1, and systolic strain in hypertrophic cardiomyopathy (HCM) and hypertensive patients with left ventricular hypertrophy ...(HTN LVH) with mildly reduced or preserved ejection fraction. Materials and methods T1 mapping was performed in 45 patients with late gadolinium enhancement positive (LGE+) HCM (mean age, 53±6 years), 11 patients with LGE− (LGE−) HCM (mean age, 56±5 years), and 20 patients with HTN LVH (mean age, 55±6 years) on at 3 T magnetic resonance imaging (MRI) using the modified look-locker inversion-recovery (MOLLI) pulse sequence. Mean T1 value, ECV and circumferential strain parameters were determined for each patient. Results Overall, the HCM patients had higher native T1 values (1242.92±68.94) and ECV (0.31±0.05) in comparison to those of the HTN LVH patients (1197±46.80, 0.27±0.04; p< 0.05). In the subgroup analysis, the HCM LGE+ patients had the highest native T1 values among the three groups. The HCM LGE+ patients had higher ECV than the LGE− patients. HCM LGE− patients had higher ECV than HTN LVH patients ( p< 0.05). Peak systolic circumferential strain and early diastolic strain rates were reduced in the HCM LGE+ patients in comparison to the HCM LGE− and HTN LVH patients ( p< 0.05). Reduced peak systolic and early diastolic circumferential strain rates were associated with increased levels of ECV and native T1 values among all the patients. Conclusion HCM LGE+ patients had higher native T1 values, higher ECV, and an associated reduction in early diastolic strain rates and peak systolic circumferential strains when compared to the HCM LGE− and HTN LVH patients with mildly reduced or preserved ejection fraction.
Abstract
Introduction
Patients with obstructive sleep apnea (OSA) commonly exhibit grey and white matter loss, which may be related to hypoxic damage in the brain during sleep. Our preliminary data ...demonstrated lower values of cerebral metabolic rate of oxygen (CMRO2) consumption in apneics versus controls. As such, reduced CMRO2 may be an important contributor to the neurologic consequences of OSA. Here we report a rodent model for chronic intermittent hypoxia (CIH) to quantify effects on CMRO2 consumption. We hypothesized that increased severity of CIH results in decreased CMRO2 levels.
Methods
Three groups of rats were subject to varying levels of hypoxia: sham (21% oxygen; n = 19), moderate (11% oxygen; n = 14), and severe (6% oxygen; n = 21). To deliver hypoxia, rats were exposed to three-minute cycles of oxygen between 21% and condition-specific nadir O2 for 12 hours daily during their sleep cycle. CMRO2 values were measured with MRI techniques, performed on anesthetized rats before and after 3 months exposure to CIH.
Results
Rats from the three hypoxia groups did not differ significantly in CMRO2 values at baseline (0 months). After 3 months of exposure to hypoxic conditions, there was a trending difference (p=0.0726) in percent change from baseline between severely hypoxic (-35.3%) and sham (+12.3%) rats. Moderately hypoxic rats demonstrated an intermediate decrease from baseline after 3 months (-19.0%).
Conclusion
Our findings suggest that increased severity of intermittent hypoxia yields a dose-response decrease in brain oxygen consumption. Our data add to the growing body of evidence on the relationship between obstructive sleep apnea and hypoxic damage in the brain, suggesting that CMRO2 levels may be an indicator of the neurologic consequences of OSA.
Support
Funded by NIH P01 HL094307
Abstract
Introduction
Cognitive and spatial dysfunction is common among patients with obstructive sleep apnea (OSA). The cause of these abnormalities may be related to the effects of hypoxic damage ...in the brain during sleep. Here we report a rodent model for chronic intermittent hypoxia (CIH) that examines spatial performance tasks via a Barnes Maze paradigm. We hypothesized that increased severity of CIH yields decreased cognitive and spatial performance.
Methods
Three groups of rats were subject to varying levels of hypoxia conditions: sham (21% oxygen; n = 19), moderate (11% oxygen; n = 14), and severe (6% oxygen; n = 21). To deliver hypoxia, rats were exposed to three-minute cycles of oxygen between 21% and condition-specific nadir oxygen for 12 hours daily (during sleep) in specialized chambers. Barnes maze testing was performed at 0, 1, 2, and 3 months. Rats were placed on a circular platform with 19 shallow holes and one deeper target hole to escape the noxious sound. Each month, rats had 3 minutes to find the target hole in four daily trials over four consecutive days. Average maze completion time on day 4 was recorded.
Results
Rats from the three hypoxia groups did not differ significantly in mean maze completion time at baseline (0 months). Throughout the three months of exposure to hypoxic conditions, maze completion time on day 4 did not differ significantly from baseline for sham rats. However, by month 3, rats exposed to severe hypoxic conditions had a significantly larger percent increase from baseline compared to sham rats (p = 0.0358).
Conclusion
Our findings indicate that rats undergoing intermittent hypoxia perform worse than normoxic rats in spatial performance tasks. These data suggest there is a relationship between CIH and cognitive/spatial impairment.
Support
Funded by NIH P01 HL094307
In candidate gene era, dozens of single-nucleotide polymorphisms (SNPs) within renin-angiotensin-aldosterone system (RAAS) have been reported to be significantly associated with hypertension. ...However, the unbiased genome-wide association studies (GWAS) rarely identified the SNPs within RAAS were associated with hypertension or blood pressure (BP) traits. In order to figure out whether genetic polymorphisms of RAAS are really associated with hypertension, we systemically searched the GWAS Catalogue and identified all the known RAAS genes and relevant diseases/traits. After data processing, we found that polymorphisms within REN, AGT, ACE2, CYP11B2, ATP6AP2 and HSD11B2 were not associated with any disease or trait. SNPs within ACE, AGTR1, AGTR2, MAS1, RENBP and NR3C2 were associated with other diseases or traits, but showed no direct connection with hypertension. The only SNP associated with a BP trait, systolic BP was rs17367504. However, it is located in the intronic region of MTHFR near many plausible candidate genes, including CLCN6, NPPA, NPPB and AGTRAP. Therefore, the effect of RAAS polymorphisms may have been overestimated during the 'candidate gene era'. In the time of 'precision medicine', the power of RAAS variants needs to be reconsidered when evaluating one's susceptibility of hypertension.
Summary Objective Investigate a role for calcitonin gene-related peptide (CGRP) in osteoarthritis (OA)-related pain. Design Neutralizing antibodies to CGRP were generated de novo . One of these ...antibodies, LY2951742, was characterized in vitro and tested in pre-clinical in vivo models of OA pain. Results LY2951742 exhibited high affinity to both human and rat CGRP (KD of 31 and 246 pM, respectively). The antibody neutralized CGRP-mediated induction of cAMP in SK-N-MC cells in vitro and capsaicin-induced dermal blood flow in the rat. Neutralization of CGRP significantly reduced pain behavior as measured by weight bearing differential in the rat monoiodoacetate model of OA pain in a dose-dependent manner. Moreover, pain reduction with neutralization of CGRP occurred independently of prostaglandins, since LY2951742 and NSAIDs worked additively in the NSAID-responsive version of the model and CGRP neutralization remained effective in the NSAID non-responsive version of the model. Neutralization of CGRP also provided dose-dependent and prolonged (>60 days) pain reduction in the rat meniscal tear model of OA after only a single injection of LY2951742. Conclusions LY2951742 is a high affinity, neutralizing antibody to CGRP. Neutralization of CGRP is efficacious in several OA pain models and works independently of NSAID mechanisms of action. LY2951742 holds promise for the treatment of pain in OA patients.
The very small strain shear modulus of soil, G
0
, is affected by many factors including soil properties, current stress state, stress history, and matric suction. Very little research has been ...conducted on anisotropic shear moduli of unsaturated soils. In this study, the effects of wetting-drying and stress ratio on anisotropic shear stiffness of an unsaturated completely decomposed tuff (CDT) at very small strains have been investigated using a modified triaxial testing system equipped with three pairs of bender elements. During drying and wetting tests, the measured very small strain shear moduli increased in a nonlinear fashion, but at a reduced rate as the matric suction increased. Similar to the stress-dependent soil-water characteristic curves (SDSWCCs), there was hysteresis between the drying and wetting curves showing the variations in shear moduli with matric suction. Variation in suction on the specimens under isotropic conditions produced changes in stiffness anisotropy (expressed as G
0(hh)
/G
0(hv)
) together with anisotropic strains. In shearing tests at constant suctions, significant stress-induced stiffness anisotropy was observed due to a change in the stress ratio. While shearing at a constant stress ratio, G
0(hh)
/G
0(hv)
appeared to be constant.
This study aimed to evaluate the effects of dietary creatine nitrate (CrN) on growth performance, meat quality, energy status, glycolysis, and related gene expression of liver kinase B1/AMP-activated ...protein kinase (LKB1/AMPK) pathway in Pectoralis major (PM) muscle of broilers. A total of 240 male Arbor Acres broilers (28-day-old) were randomly allocated to one of 5 dietary treatments: the basal diet (control group), and the basal diets supplemented with 600 mg/kg guanidinoacetic acid (GAA), 300, 600, or 900 mg/kg CrN (identified as GAA600, CrN300, CrN600, or CrN900, respectively). We found that dietary GAA and CrN supplementation for 14 d from d 28 to 42 did not affect broiler growth performance, carcass traits, and textural characteristics of breast muscle. GAA600, CrN600, and CrN900 treatments increased pH24h and decreased drip loss of PM muscle compared with the control (P < 0.05). The PM muscles of CrN600 and CrN900 groups showed higher glycogen concentration and lower lactic acid concentration accompanied by lower activities of phosphofructokinase (PFK), pyruvate kinase (PK), and lactate dehydrogenase (LDH) (P < 0.05). Simultaneously, GAA600 and all CrN treatments increased concentration of muscle creatine, phosphocreatine (PCr) and ATP, and decreased AMP concentration and AMP/ATP ratio (P < 0.05). Meanwhile, the concentrations of muscle creatine, PCr, and ATP were increased linearly, while muscle AMP concentration and AMP/ATP ratio were decreased linearly and quadratic as the dose of CrN increased (P < 0.05). GAA600, CrN600, and CrN900 treatments upregulated mRNA expression of CreaT in PM muscle, and CrN600 and CrN900 treatments downregulated GAMT expression in liver and PM muscle compared with the control or GAA600 groups (P < 0.05). The mRNA expression of muscle LKB1, AMPKα1, and AMPKα2 was downregulated linearly in response to the increasing CrN level (P < 0.05). Overall, CrN showed better efficacy on strengthening muscle energy status and improve meat quality than GAA at the some dose. These results indicate that CrN may be a potential replacement for GAA as a new creatine supplement.
To determine the effects of a low-fat plant-based diet program on anthropometric and biochemical measures in a multicenter corporate setting.
Employees from 10 sites of a major US company with body ...mass index ≥ 25 kg/m(2) and/or previous diagnosis of type 2 diabetes were randomized to either follow a low-fat vegan diet, with weekly group support and work cafeteria options available, or make no diet changes for 18 weeks. Dietary intake, body weight, plasma lipid concentrations, blood pressure and glycated hemoglobin (HbA1C) were determined at baseline and 18 weeks.
Mean body weight fell 2.9 kg and 0.06 kg in the intervention and control groups, respectively (P<0.001). Total and low-density lipoprotein (LDL) cholesterol fell 8.0 and 8.1 mg/dl in the intervention group and 0.01 and 0.9 mg/dl in the control group (P<0.01). HbA1C fell 0.6 percentage point and 0.08 percentage point in the intervention and control group, respectively (P<0.01).Among study completers, mean changes in body weight were -4.3 kg and -0.08 kg in the intervention and control groups, respectively (P<0.001). Total and LDL cholesterol fell 13.7 and 13.0 mg/dl in the intervention group and 1.3 and 1.7 mg/dl in the control group (P<0.001). HbA1C levels decreased 0.7 percentage point and 0.1 percentage point in the intervention and control group, respectively (P<0.01).
An 18-week dietary intervention using a low-fat plant-based diet in a corporate setting improves body weight, plasma lipids, and, in individuals with diabetes, glycemic control.
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