Synergistic effect of Ni–Ag–rutile TiO2 ternary nanocomposite for efficient visible-light-driven photocatalytic activity

P25 comprising of mixed anatase and rutile phases is known to be highly photocatalytically active compared to the individual phases. Using a facile wet chemical method, we demonstrate a ternary nanocomposite consisting of Ni and Ag nanoparticles, decorated on the surface of XTiO₂ (X: P25, rutile (R)) as an efficient visible-light-driven photocatalyst. Contrary to the current perspective, RTiO₂-based Ni–Ag–RTiO₂ shows the highest activity with the H₂ evolution rate of ∼86 μmol g⁻¹ W⁻¹ h⁻¹@535 nm. Together with quantitative assessment of active Ni, Ag and XTiO₂ in these ternary systems using high energy synchrotron X-ray diffraction, transmission electron microscopy coupled energy dispersive spectroscopy mapping evidences the metal to semiconductor contact via Ag. The robust photocatalytic activity is attributed to the improved visible light absorption, as noted by the observed band edge of ∼2.67 eV corroborating well with the occurrence of Ti³⁺ in Ti 2p XPS. The effective charge separation due to intimate contact between Ni and RTiO₂via Ag is further evidenced by the plasmon loss peak in Ag 3d XPS. Moreover, density functional theory calculations revealed enhanced adsorption of H₂ on Ti₈O₁₆ clusters when both Ag and Ni are simultaneously present, owing to the hybridization of the metal atoms with d orbitals of Ti and p orbitals of O leading to enhanced bonding characteristics, as substantiated by the density of states. Additionally, the variation in the electronegativity in Bader charge analysis indicates the possibility of hydrogen evolution at the Ni sites, in agreement with the experimental observations.

Robust photocatalytic activity of Ni–Ag–RTiO₂ is attributed to the improved visible light absorption and effective charge separation due to intimate contact between Ni and RTiO₂via Ag, as evidenced by Ti³⁺ in Ti 2p XPS and energy dispersive mapping.     

The Association of Time to Organ Procurement on Short- and Long-Term Outcomes in Kidney Transplantation

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Thickness distribution of the glenohumeral joint cartilage: a quantitative study using computed tomography

Purpose

Among late signs like sclerosis, cysts and osteophytes, alteration of cartilage is a common problem in osteoarthritis. To detect abnormal states in the glenohumeral joint, the physiologic distribution of the cartilage thickness must be known, which will allow physicians to better advise patients. High-resolution computed tomography (CT) data in soft tissue kernel provide highly accurate quantitative results and are a useful method to determine the geometrical situation of the glenohumeral joint. The objective of this study was to characterize the distribution of the thickness of the glenohumeral joint cartilage using CT.

Methods

To investigate the distribution of thickness of the joint cartilage, CT images in soft tissue kernel of nine specimens were analyzed using image visualization software. Statistical analysis of the obtained data was performed using the ANOVA test.

Results

Results showed different patterns in the glenoid cavity than in humeral head. Cartilage thickness in all glenoids showed maxima in the inferior and anterior portion, whereas central areas are covered with the thinnest cartilage layer. Maximum cartilage thickness in the humeral head was found in the central and superior parts.

Conclusion

We could show that the distribution of cartilage thickness in the glenohumeral joint is not homogenous and that there exist several reproducible patterns. Evaluation of cartilage thickness in the glenohumeral joint is of high interest in basic and clinical research.     

Adipokines and proinflammatory cytokines,the key mediators in the pathogenesis of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a condition in which excess fat accumulates in the liver of a patient with no history of alcohol abuse or other causes for secondary hepatic steatosis. The pathogenesis of NAFLD and nonalcoholic steatohepatitis (NASH) has not been fully elucidated. The “two-hit“ hypothesis is probably a too simplified model to elaborate complex pathogenetic events occurring in patients with NASH. It should be better regarded as a multiple step process, with accumulation of liver fat being the first step, followed by the development of necroinflammation and fibrosis. Adipose tissue, which has emerged as an endocrine organ with a key role in energy homeostasis, is responsive to both central and peripheral metabolic signals and is itself capable of secreting a number of proteins. These adipocyte-specific or enriched proteins, termed adipokines, have been shown to have a variety of local, peripheral, and central effects. In the current review, we explore the role of adipocytokines and proinflammatory cytokines in the pathogenesis of NAFLD. We particularly focus on adiponectin, leptin and ghrelin, with a brief mention of resistin, visfatin and retinol-binding protein 4 among adipokines, and tumor necrosis factor-α, interleukin (IL)-6, IL-1, and briefly IL-18 among proinflammatory cytokines. We update their role in NAFLD, as elucidated in experimental models and clinical practice.     

Arterial pulse wave velocity in relation to carotid intima-media thickness, brachial flow-mediated dilation and carotid artery distensibility: the Cardiovascular Risk in Young Finns Study and the Health 2000 Survey

ObjectiveIncreased arterial pulse wave velocity (PWV) is a strong predictor of cardiovascular events and mortality. The data regarding the relationships between PWV and other indices of vascular damage is limited and partly controversial. We conducted the present study to examine PWV in relation to non-invasive measures of early atherosclerosis (brachial flow-mediated dilation [FMD], carotid intima-media thickness [IMT]) and local arterial stiffness (carotid artery distensibility [Cdist]).MethodsThe study population consisted of 1754 young adults (aged 30–45 years, 45.5% males) participating in the Cardiovascular Risk in Young Finns Study (YFS), and of 336 older adults (aged 46–76 years, 43.2% males) participating in the Health 2000 Survey. FMD was measured only in the YFS cohort. FMD, IMT and Cdist were assessed by ultrasound, and PWV was measured using the whole-body impedance cardiography device.ResultsIn young adults, FMD and IMT were not associated with PWV independently of cardiovascular risk factors. Moreover, FMD status was not found to modulate the association between cardiovascular risk factors and PWV. In older adults, PWV and IMT were directly and independently associated (β = 1.233, p = 0.019). In both cohorts, PWV was inversely related with Cdist, and this relation remained significant (p < 0.04) in models adjusted for cardiovascular risk factors.ConclusionsThe current findings suggest that PWV reflects a different aspect of vascular damage than FMD or IMT in young adults, whereas in older adults the information provided by PWV and IMT may be, to some extent, similar as regards subclinical vascular damage. The present observations also suggest that PWV and Cdist represent, at least in part, a similar adverse vascular wall process.     

The Influence of Etiologic Factors on Clinical Outcome in Patients with Peptic Ulcer Bleeding

Background

Peptic ulcer bleeding remains an important cause of morbidity and mortality.

Aim

The aim of this study was to evaluate the prevalence of non-steroidal anti-inflammatory drugs (NSAID) use, Helicobacter pylori infection and non-H. pylori?Cnon-NSAIDs causes of peptic ulcer bleeding and to identify the predictive factors influencing the rebleeding rate and in-hospital mortality in patients with bleeding peptic ulcer.

Methods

A total of 1,530 patients with endoscopically confirmed peptic ulcer bleeding were evaluated consecutively between January 2005 and December 2009. The 30-day mortality and clinical outcome were related to patient??s demographic data, endoscopic and clinical characteristics.

Results

The age-standardized 1-year cumulative incidence for peptic ulcer bleeding was 40.4 cases/100,000 people. The proportion of patients over 65?years increased from 45.7?% in 2005 to 61.4?% in 2009 (p?=?0.007). Overall 30-day mortality rate was 4.6?%, not significantly different for conservatively and surgically treated patients (4.9 vs. 4.1?%, p?=?0.87). Mortality was significantly higher in patients over 65?years of age and those with in-hospital bleeding recurrence. Patients with non-H. pylori?Cnon-NSAID idiopathic ulcers had significantly higher 30-day mortality rate than those with H. pylori ulcers and NSAID?CH. pylori ulcers (7.1 vs. 0 vs. 0.8?%, p?=?0.001 and p?=?0.007, respectively). There was no statistically significant difference between patients with NSAID ulcers and non-H. pylori?Cnon-NSAID idiopathic ulcers in terms of 30-day mortality rate (5.3 vs. 7.1?%, p?=?0.445).

Conclusion

The incidence of peptic ulcer bleeding has not changed over a 5-year observational period. The overall 30-day mortality was positively correlated to older age, underlying comorbid illnesses, in-hospital bleeding recurrence and the absence of H. pylori infection.