Renal Function and Risk Factors of Moderate to Severe Chronic Kidney Disease in Golestan Province, Northeast of Iran

Introduction: The incidence of end-stage renal disease is increasing worldwide. Earlier studies reported high prevalence rates of obesity and hypertension, two major risk factors of chronic kidney disease (CKD), in Golestan Province, Iran. We aimed to investigate prevalence of moderate to severe CKD and its risk factors in the region. Methods: Questionnaire data and blood samples were collected from 3591 participants (≥18 years old) from the general population. Based on serum creatinine levels, glomerular filtration rate (GFR) was estimated. Results: High body mass index (BMI) was common: 35.0 of participants were overweight (BMI 25-29.9) and 24.5 were obese (BMI ≥30). Prevalence of CKD stages 3 to 5 (CKD-S3-5), i.e., GFR <60 mL/min/1.73 m2, was 4.6. The odds ratio (OR) and 95 confidence interval (95 CI) for the risk of CKD-S3-5 associated with every year increase in age was 1.13 (1.11- 1.15). Men were at lower risk of CKD-S3-5 than women (OR = 0.28; 95 CI 0.18-0.45). Obesity (OR = 1.78; 95 CI 1.04-3.05) and self-reported diabetes (OR = 1.70; 95 CI 1.00-2.86), hypertension (OR = 3.16; 95 CI 2.02-4.95), ischemic heart disease (OR = 2.73; 95 CI 1.55-4.81), and myocardial infarction (OR = 2.69; 95 CI 1.14-6.32) were associated with increased risk of CKD-S3-5 in the models adjusted for age and sex. The association persisted for self-reported hypertension even after adjustments for BMI and history of diabetes (OR = 2.85; 95 CI 1.77-4.59). Conclusion: A considerable proportion of inhabitants in Golestan have CKD-S3-5. Screening of individuals with major risk factors of CKD, in order to early detection and treatment of impaired renal function, may be plausible. Further studies on optimal risk prediction of future end-stage renal disease and effectiveness of any screening program are warranted. © 2010 Najafi et al

Population-level risks of alcohol consumption by amount, geography, age, sex, and year: a systematic analysis for the Global Burden of Disease Study 2020

Background The health risks associated with moderate alcohol consumption continue to be debated. Small amounts of alcohol might lower the risk of some health outcomes but increase the risk of others, suggesting that the overall risk depends, in part, on background disease rates, which vary by region, age, sex, and year. Methods For this analysis, we constructed burden-weighted dose–response relative risk curves across 22 health outcomes to estimate the theoretical minimum risk exposure level (TMREL) and non-drinker equivalence (NDE), the consumption level at which the health risk is equivalent to that of a non-drinker, using disease rates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2020 for 21 regions, including 204 countries and territories, by 5-year age group, sex, and year for individuals aged 15–95 years and older from 1990 to 2020. Based on the NDE, we quantified the population consuming harmful amounts of alcohol. Findings The burden-weighted relative risk curves for alcohol use varied by region and age. Among individuals aged 15–39 years in 2020, the TMREL varied between 0 (95% uncertainty interval 0–0) and 0·603 (0·400–1·00) standard drinks per day, and the NDE varied between 0·002 (0–0) and 1·75 (0·698–4·30) standard drinks per day. Among individuals aged 40 years and older, the burden-weighted relative risk curve was J-shaped for all regions, with a 2020 TMREL that ranged from 0·114 (0–0·403) to 1·87 (0·500–3·30) standard drinks per day and an NDE that ranged between 0·193 (0–0·900) and 6·94 (3·40–8·30) standard drinks per day. Among individuals consuming harmful amounts of alcohol in 2020, 59·1% (54·3–65·4) were aged 15–39 years and 76·9% (73·0–81·3) were male. Interpretation There is strong evidence to support recommendations on alcohol consumption varying by age and location. Stronger interventions, particularly those tailored towards younger individuals, are needed to reduce the substantial global health loss attributable to alcohol. Funding Bill & Melinda Gates Foundation

Microstructure and compressibility of SiC nanoparticle reinforced Cu nanocomposite powders processed by high energy mechanical milling

Cu/SiC nanocomposite powders with homogeneously distributed nanosize SiC particles were produced by high energy mechanical milling (MM). Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and micro-hardness and density measurements were performed to understand the effects of microstructure and hardness on compaction behavior during MM. The effects of SiC nanoparticle content and mechanical milling time on apparent density (AD) and tap density (TD) of the nanocomposite powders were systematically investigated. The Hausner ratio (HR), defined as TD to AD, were estimated to evaluate friction between the particles. Increasing MM duration and SiC content resulted in a decrease in HR due to the changes in morphology and hardness of the powders. Additionally, the compressibility behavior of the powders was theoretically examined using a compaction equation to investigate the deformation capacity. Densification parameters of the nanocomposite powders showed a significant decrease with increasing MM duration and a slight decrease with increasing SiC content. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Fabrication, characterization and mechanical properties of hybrid composites of copper using the nanoparticulates of SiC and carbon nanotubes

Copper based hybrid composites containing nano-sized silicon carbide and carbon nanotubes reinforcements with minimal porosity were fabricated via mechanical milling followed by hot pressing technique. Microstructures of the powders and consolidated materials were studied using scanning electron microscope, X-ray diffraction, Raman spectroscopy, and scanning transmission electron microscope. Microstructural characterization of the materials revealed that the addition of nanosized silicon carbide reinforcement lowered the grain growth rate and enhanced the homogenization during mechanical milling. Microhardness measurements and compression test showed considerable improvements in mechanical properties of the composites due to the addition of nanoparticulates and the grain refinement. The strength of the composite materials was discussed using theoretical models of the Hall-Fetch, Orowan, and thermal mismatch mechanisms to determine the contribution of each mechanism in total strength. (C) 2013 Elsevier B.V. All rights reserved.X112723sciescopu

Effect of nanoparticle content on the microstructural and mechanical properties of nano-SiC dispersed bulk ultrafine-grained Cu matrix composites

In this study, the microstructural and mechanical features of monolithic pure Cu and Cu matrix nanocomposites reinforced with three different fractions (2, 4, and 6 vol%) of SiC nanoparticles (n-SiC) fabricated via a combination of high energy mechanical milling and hot pressing techniques were investigated. The fabricated composites exhibited homogeneous distribution of the n-SiC with few porosities. It was found that the grain refinement, the planar features within the grains, and the lattice strains increase with increase in the n-SiC content. The yield and compressive strengths of the nanocomposites were significantly improved with increases in the n-SiC content up to 4 vol%; then they decreased due to the weak interface strength at higher amounts of n-SiC content. This improvement was attributed to the grain refinement strengthening and homogeneous distribution of the n-SiC. Furthermore, studies on different strengthening mechanisms showed that Hall-Petch strengthening mechanism is the most important factor. The yield strength was calculated theoretically using common analytical models. Clyne approach showed good agreement with experimental data and were more accurate than the other methods developed for predicting the strength of metal matrix nanocomposites. (C) 2013 Elsevier Ltd. All rights reserved.X113431sciescopu

Microstructure and compressibility of SiC nanoparticles reinforced Cu nanocomposite powders processed by high energy mechanical milling

Cu/SiC nanocomposite powders with homogeneously distributed nanosize SiC particles were produced by high energy mechanical milling (MM). Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and micro-hardness and density measurements were performed to understand the effects of microstructure and hardness on compaction behavior during MM. The effects of SiC nanoparticle content and mechanical milling time on apparent density (AD) and tap density (TD) of the nanocomposite powders were systematically investigated. The Hausner ratio (HR), defined as TD to AD, were estimated to evaluate friction between the particles. Increasing MM duration and SiC content resulted in a decrease in HR due to the changes in morphology and hardness of the powders. Additionally, the compressibility behavior of the powders was theoretically examined using a compaction equation to investigate the deformation capacity. Densification parameters of the nanocomposite powders showed a significant decrease with increasing MM duration and a slight decrease with increasing SiC content. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.112725sciescopu

Microstructural development and mechanical properties of nanostructured copper reinforced with SiC nanoparticles

Nanostructured Cu and Cu-2 vol% SiC nanocomposite were produced by high energy mechanical milling and hot pressing technique. Microstructure development during fabrication process was investigated by X-ray diffraction, scanning electron microscope, scanning transmission electron microscope, and electron backscatter diffraction techniques. The results showed that the microstructure of copper and copper-based nanocomposite composed of a mixture of equiaxed nanograins with bimodal and non-random misorientation distribution. The presence of SiC nanoparticles refined the grain structure of the copper matrix while the fraction of low angle grain boundaries was increased. Evaluation of mechanical properties by compression test showed enhanced yield strength from 505 +/- 17 MPa for the nanostructured copper to 630 +/- 12 MPa for the reinforced metal with 2 vol% SiC. We correlated the strength of the nanostructured materials to their microstructural features based on the strengthening mechanisms. The contribution of different mechanisms including Orowan strengthening, high angle grain boundaries, and density of dislocations were analyzed. It is shown that the high angle grain boundaries in nanostructured materials play a significant role in the strengthening mechanism. The effect of nanoparticles is presented and discussed. (c) 2013 Elsevier B.V. All rights reserved.X112122sciescopu

Molecular Detection of Leishmania major in the Vectors and Reservoir Hosts of Cutaneous Leishmaniasis in Kalaleh District, Golestan Province, Iran

Background: An epidemiological study was carried out on the vector(s) and reservoir(s) of cutaneous leishmaniasis in rural areas of Kalaleh District, Golestan Province during 2006 - 2007. Methods: Totally 4900 sand flies were collected using sticky papers and were subjected to molecular methods for de­tection of leishmanial parasite. Results: Phlebotomus papatasi was the common species in outdoor and indoor resting places. Employing PCR tech­nique showed only 1 out of 372 P. papatasi (0.3%) was positive to parasite due Leishmania major. Sixteen ro­dent reservoir hosts were captured by Sherman traps and identified as Rhombomys opimus. Microscopic investiga­tion on blood smear of the animals for amastigote parasites revealed 6(37.5%) infected rodents. Infection of these ani­mals to L. major was then confirmed by PCR against rDNA loci of the parasite. Conclusion: This is the first molecular report of parasite infection of both vector (P. papatas) and reservoir (R. opimus) to L. major. The results indicated that P. papatas was the primary vector of the disease and circulating the para­site between human and reservoirs, and R. opimus was the most important host reservoir for maintenance of the para­site source in the area