Study of the Structure Effect on Water Adsorption by a Group of Nano Copper Clusters

According to the previous studies, water adsorption energy on the metal surface like as Cu strongly dependent to the structure surface and the size. During the study of the mechanism of the interaction of water and Cu in water gas shift reaction (WGSR) (CO + H2O CO2 + H2), it has been determined Cu is active site of catalysis. These studies inspired the authors to consider theoretically the effect of the structure in the process of the water adsorption in order to select the suitable structures of the copper clusters, Cu10, for H2 releasing in the fuel cells at B3LYP/6-31G level of theory. The results showed the distinct effect of the structure on the type of adsorption process (physical or chemical) through three structure of Cu10 (I, II, III structures, Fig. 1). The structures I and II showed physical surface adsorption in reaction with water and the structure III showed chemical adsorption with H2 releasing. The adsorption energies are 0.38 ,1.15 ,-28.27 (kcal/mol) and ΔGads are 11.14, 13.49, -20.12 (kcal/mol), respectively. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3513

Nitazoxanide and doxycycline sensitivity among metronidazole resistant helicobacter pylori isolates from patients with gastritis

Background: Antibiotic therapy should be done based on resistance characteristics of Helicobacter pylori strains to commonly prescribed antibiotics in areas with higher resistance rates. Objectives: This study examined antibacterial activity of nitazoxanide and doxycycline against clinical H. pylori isolates showing different metronidazole resistance levels. Methods: A total of 122 patients, who underwent endoscopy were enrolled in this study from 3 hospitals of Tehran, during November 2014 to July 2015. Helicobacter pylori isolates were obtained from gastric biopsies of the patients after culture in specific culture medium and characterization by both biochemical and molecular methods. Antimicrobial susceptibility to metronidazole was detected using the agar dilution method and minimum inhibitory concentrations of nitazoxanide and doxycycline were determined for metronidazole resistant strains. Results: From a total of 122 gastric biopsy specimens, 55 H. pylori strains were recovered (45). Thirty-three of these strains (60.0) were resistance to metronidazole. MIC50 and MIC90 values for metronidazole were 32 and 64 µg/mL, respectively. MIC50 and MIC90 values for doxycycline and nitazoxanide were measured as 4 and �8 µg/mL, and 8 and �32 µg/mL, respectively. Conclusions: Dominance of high level metronidazole resistance H. pylori strains among the studied patients questioned its usefulness for first-line therapy in Iran. Nitazoxanide and doxycycline showed superior activity against H. pylori strains in comparison to metronidazole, which should be considered for alternative therapies. © 2018, Kowsar Medical Publishing Company. All rights reserved

Development of a New Kinetic Model for Methanol to Propylene Process on Mn/H-ZSM-5 Catalyst

The activity of the H-ZSM-5 was modified by the addition of Ca, Mn, Cr, Fe, Ni, Ag, Ce and P. The highest selectivity of propylene was obtained over the Mn/H-ZSM-5 catalyst. The Mn modified catalyst was selected as the optimal catalyst and the kinetic study was carried out on it. All of the experiments were carried out in an isothermal fixed bed and plug flow reactor with the mixture of methanol and water. The temperature range was 400–550 °C and the weight hourly space velocities (WHSV) of methanol were: 2.51, 5.42, and 8.17 h–1. A reaction mechanism based on the theory of hydrocarbon pool and conjugate methylation/cracking mechanisms was proposed. The behavior of the reactor was mathematically modeled and the hybrid genetic algorithm was applied to estimate kinetic parameters. Good agreement was observed between the experimental and the calculated data. Effect of temperature on propylene selectivity was also investigated. It was found that the propylene selectivity steadily increases with temperature

Nitazoxanide and doxycycline sensitivity among metronidazole resistant helicobacter pylori isolates from patients with gastritis

Background: Antibiotic therapy should be done based on resistance characteristics of Helicobacter pylori strains to commonly prescribed antibiotics in areas with higher resistance rates. Objectives: This study examined antibacterial activity of nitazoxanide and doxycycline against clinical H. pylori isolates showing different metronidazole resistance levels. Methods: A total of 122 patients, who underwent endoscopy were enrolled in this study from 3 hospitals of Tehran, during November 2014 to July 2015. Helicobacter pylori isolates were obtained from gastric biopsies of the patients after culture in specific culture medium and characterization by both biochemical and molecular methods. Antimicrobial susceptibility to metronidazole was detected using the agar dilution method and minimum inhibitory concentrations of nitazoxanide and doxycycline were determined for metronidazole resistant strains. Results: From a total of 122 gastric biopsy specimens, 55 H. pylori strains were recovered (45). Thirty-three of these strains (60.0) were resistance to metronidazole. MIC50 and MIC90 values for metronidazole were 32 and 64 µg/mL, respectively. MIC50 and MIC90 values for doxycycline and nitazoxanide were measured as 4 and �8 µg/mL, and 8 and �32 µg/mL, respectively. Conclusions: Dominance of high level metronidazole resistance H. pylori strains among the studied patients questioned its usefulness for first-line therapy in Iran. Nitazoxanide and doxycycline showed superior activity against H. pylori strains in comparison to metronidazole, which should be considered for alternative therapies. © 2018, Kowsar Medical Publishing Company. All rights reserved

A Spatio-Temporal Ageing Atlas of the Proximal Femur

Osteoporosis is an age-associated disease characterised by low bone mineral density (BMD) and micro-architectural deterioration leading to enhanced fracture risk. Conventional dual-energy X-ray absorptiometry (DXA) analysis has facilitated our understanding of BMD reduction in specific regions of interest (ROIs) within the femur, but cannot resolve spatial BMD patterns nor reflect age-related changes in bone microarchitecture due to its inherent averaging of pixel BMD values into large ROIs. To address these limitations and develop a comprehensive model of involutional bone loss, this paper presents a fully automatic pipeline to build a spatio-temporal atlas of ageing bone in the proximal femur. A new technique, termed DXA region free analysis (DXA RFA), is proposed to eliminate morphological variation between DXA scans by warping each image into a reference template. To construct the atlas, we use unprocessed DXA data from Caucasian women aged 20-97 years participating in three cohort studies in Western Europe (n > 13 ,000). A novel calibration procedure, termed quantile matching regression, is proposed to integrate data from different DXA manufacturers. Pixel-wise BMD evolution with ageing was modelled using smooth quantile curves. This technique enables characterisation of spatially-complex BMD change patterns with ageing, visualised using heat-maps. Furthermore, quantile curves plotted at different pixel coordinates showed consistently different rates of bone loss at different regions within the femoral neck. Given the close relationship between spatio-temporal bone loss and osteoporotic fracture, improved understanding of the bone ageing process could lead to enhanced prognostic, preventive and therapeutic strategies for the disease

Gabapentin for the hemodynamic response to intubation: systematic review and meta-analysis

Purpose Endotracheal intubation is the gold standard for securing the airway before surgery. Nevertheless, this procedure can produce an activation of the sympathetic nervous system and result in a hemodynamic response which, in high-risk patients, may lead to cardiovascular instability and myocardial ischemia. The aim of this review was to evaluate whether gabapentin can attenuate this response and whether such an attenuation could translate into reduced myocardial ischemia and mortality. Source We searched MEDLINE®, EMBASE™, CINAHL, AMED, and unpublished clinical trial databases for randomized-controlled trials that compared gabapentin with control, fentanyl, clonidine, or beta blockers for attenuating the hemodynamic response to intubation. Primary outcomes were mortality, myocardial infarction, and myocardial ischemia. Secondary outcomes were hemodynamic changes following intubation. Principal findings We included 29 randomized trials with only two studies at low risk of bias. No data were provided for the primary outcomes and no studies included high-risk patients. The use of gabapentin resulted in attenuation in the rise in mean arterial blood pressure [mean difference (MD), −12 mmHg; 95% confidence interval (CI), −17 to −8] and heart rate (MD, −8 beats·min−1; 95% CI, −11 to −5) one minute after intubation. Gabapentin also reduced the risk of hypertension or tachycardia requiring treatment (risk ratio, 0.15; 95% CI, 0.05 to 0.48). Data were limited on adverse hemodynamic events such as bradycardia and hypotension. Conclusion It remains unknown whether gabapentin improves clinically relevant outcomes such as death and myocardial infarction since studies failed to report on these. Nevertheless, gabapentin attenuated increases in heart rate and blood pressure following intubation when compared with the control group. Even so, the studies included in this review were at potential risk of bias. Moreover, they did not include high-risk patients or report adverse hemodynamic outcomes. Future studies are required to address these limitations

Global variation in diabetes diagnosis and prevalence based on fasting glucose and hemoglobin A1c

Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) are both used to diagnose diabetes, but these measurements can identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening, had elevated FPG, HbA1c or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardized proportion of diabetes that was previously undiagnosed and detected in survey screening ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the age-standardized proportion who had elevated levels of both FPG and HbA1c was 29–39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c was more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global shortfall in diabetes diagnosis and surveillance

Global variations in diabetes mellitus based on fasting glucose and haemogloblin A1c

Fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) are both used to diagnose diabetes, but may identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening had elevated FPG, HbA1c, or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardised proportion of diabetes that was previously undiagnosed, and detected in survey screening, ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the agestandardised proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global gap in diabetes diagnosis and surveillance.peer-reviewe

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI 2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining https://researchonline.ljmu.ac.uk/images/research_banner_face_lab_290.jpgunderweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity