28 research outputs found
Pelvic Incidence Angle in Standing, Maximal Anterior and Maximal Posterior Pelvic Rotation in a Sample of Healthy Subjects
This study aimed to investigate the differences in pelvic incidence (PI) between three standing, maximal anterior and maximal posterior pelvic rotation. This cross-sectional study was done on 150 healthy subjects. Lateral spine radiography was taken in 3 different positions in the same standard radiographic protocol. Sacral slope (SS) pelvic tilt (PT), lumbar lordosis (LL) and lumbosacral junction angle were measured by two independent, experienced spine surgeons. PI was calculated as sum SS and PT. The mean of PI in standing positions was 52.6±5.1, in anterior position was 52.6±5.5 and in posterior position was 52.3±5.2 degree. The mean of PI, PT, and SS in total and between male and female subjects was not statistically significant in three different positions (P>0.05). PI in 136 subjects (90.7%) is changed when the position was changed from standing to the posterior position, by mean of 2.06 degree. When the position was changed from standing to an anterior position, the change in PI degree was observed in 126 subjects (84%) by mean of 2.12 degree. Despite the none, significant value of PI in three different positions, a large number of subjects with a change in their PI when the position was changed to anterior or posterior (90.1%) position, show that PI can be varied by pelvic rotation in healthy adult subjects
Individual Radiosensitivity Assessment of the Families of Ataxia-Telangiectasia Patients by G2-Checkpoint Abrogation
Objectives: Ataxia-telangiectasia (A-T) is an autosomal recessive multisystem disorder characterised by cerebellar degeneration, telangiectasia, radiation sensitivity, immunodeficiency, oxidative stress and cancer susceptibility. Epidemiological research has shown that carriers of the heterozygous ataxia-telangiectasia mutated (ATM) gene mutation are radiosensitive to ionising irradiation and have a higher risk of cancers, type 2 diabetes and atherosclerosis. However, there is currently no fast and reliable laboratory-based method to detect heterozygous ATM carriers for family screening and planning purposes. This study therefore aimed to evaluate the ability of a modified G2-assay to identify heterozygous ATM carriers in the families of A-T patients. Methods: This study took place at the Tehran University of Medical Sciences, Tehran, Iran, between February and December 2017 and included 16 A-T patients, their parents (obligate heterozygotes) and 30 healthy controls. All of the subjects underwent individual radiosensitivity (IRS) assessment using a modified caffeine-treated G2-assay with G2-checkpoint abrogation. Results: The mean IRS of the obligate ATM heterozygotes was significantly higher than the healthy controls (55.13% ± 5.84% versus 39.03% ± 6.95%; P <0.001), but significantly lower than the A-T patients (55.13% ± 5.84% versus 87.39% ± 8.29%; P = 0.001). A receiver operating characteristic (ROC) curve analysis of the G2-assay values indicated high sensitivity and specificity, with an area under the ROC curve of 0.97 (95% confidence interval: 0.95–1.00). Conclusion: The modified G2-assay demonstrated adequate precision and relatively high sensitivity and specificity in detecting heterozygous ATM carriers.
Keywords: Ataxia-Telangiectasia; Chromosome Breakage; Genetic Carrier Screening; Heterozygote; Radiation Sensitivity; Sensitivity and Specificity
COVID‑19 associated rhino‑orbito‑cerebral mucormycosis, risk factors and outcome predictors; a multicentric study
Background Since the onset of the Covid-19 pandemic,
an increase in mucormycosis cases has been
observed in many countries, including Iran. However,
the role of covid-19 and associated risk factors have
not been thoroughly investigated.
Objective This study is designed to identify epidemiologic
characteristics, risk factors, and outcome predictors of Covid-19-Associated Rhino-Orbito-Cerebral
Mucormycosis (C-ROCM).
Methods Data of pathology proven Covid Associated
ROCM cases were retrospectively obtained from
7 tertiary care centers throughout Iran from February
20, 2021, to July 22, 2021. Univariate and multivariate
analyses were performed using binary logistic
regression to assess the effects of various factors on
the outcome.
Results A total of 132 patients with C-ROCM were
included in the study. The mean age of patients was
61.6 ± 13.9 (60.6% male). In 12 patients (9.1%),
both eyes were involved. Diabetes was the mostcommon comorbidity (94.7%). The mortality rate was
9.1%, higher in males (12.5%) than females (3.8%).
Severe vision impairment was seen in 58 patients
(43.9%). Main factors that had a negative impact on
the outcome in the univariate analysis include older
age (P < 0.001), higher steroid dosage (P < 0.001),
higher HbA1c level (P < 0.001), Covid-19 severity
(P < 0.001), and brain involvement (P < 0.001). However,
in the multivariate analysis, the effects of age
(P = 0.062), steroid dosage (P = 0.226), and Covid-
19 intensity (P = 0.084) decreased, and the difference
was no longer statistically significant. CRAO
was a predictor of mortality in the univariate analysis
(P = 0.008, OR = 4.50), but in the multivariate analysis,
this effect decreased and was no longer significant
(P = 0.125).
Conclusion The risk of C-ROCM and its complications
may increase in patients with more severe
Covid-19, steroid over-prescription, ICU admission
due to Covid-19, and poor glycemic control during
and after Covid-19 treatment
Burden of disease scenarios for 204 countries and territories, 2022–2050: a forecasting analysis for the Global Burden of Disease Study 2021
Background: Future trends in disease burden and drivers of health are of great interest to policy makers and the public at large. This information can be used for policy and long-term health investment, planning, and prioritisation. We have expanded and improved upon previous forecasts produced as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) and provide a reference forecast (the most likely future), and alternative scenarios assessing disease burden trajectories if selected sets of risk factors were eliminated from current levels by 2050. Methods: Using forecasts of major drivers of health such as the Socio-demographic Index (SDI; a composite measure of lag-distributed income per capita, mean years of education, and total fertility under 25 years of age) and the full set of risk factor exposures captured by GBD, we provide cause-specific forecasts of mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) by age and sex from 2022 to 2050 for 204 countries and territories, 21 GBD regions, seven super-regions, and the world. All analyses were done at the cause-specific level so that only risk factors deemed causal by the GBD comparative risk assessment influenced future trajectories of mortality for each disease. Cause-specific mortality was modelled using mixed-effects models with SDI and time as the main covariates, and the combined impact of causal risk factors as an offset in the model. At the all-cause mortality level, we captured unexplained variation by modelling residuals with an autoregressive integrated moving average model with drift attenuation. These all-cause forecasts constrained the cause-specific forecasts at successively deeper levels of the GBD cause hierarchy using cascading mortality models, thus ensuring a robust estimate of cause-specific mortality. For non-fatal measures (eg, low back pain), incidence and prevalence were forecasted from mixed-effects models with SDI as the main covariate, and YLDs were computed from the resulting prevalence forecasts and average disability weights from GBD. Alternative future scenarios were constructed by replacing appropriate reference trajectories for risk factors with hypothetical trajectories of gradual elimination of risk factor exposure from current levels to 2050. The scenarios were constructed from various sets of risk factors: environmental risks (Safer Environment scenario), risks associated with communicable, maternal, neonatal, and nutritional diseases (CMNNs; Improved Childhood Nutrition and Vaccination scenario), risks associated with major non-communicable diseases (NCDs; Improved Behavioural and Metabolic Risks scenario), and the combined effects of these three scenarios. Using the Shared Socioeconomic Pathways climate scenarios SSP2-4.5 as reference and SSP1-1.9 as an optimistic alternative in the Safer Environment scenario, we accounted for climate change impact on health by using the most recent Intergovernmental Panel on Climate Change temperature forecasts and published trajectories of ambient air pollution for the same two scenarios. Life expectancy and healthy life expectancy were computed using standard methods. The forecasting framework includes computing the age-sex-specific future population for each location and separately for each scenario. 95% uncertainty intervals (UIs) for each individual future estimate were derived from the 2·5th and 97·5th percentiles of distributions generated from propagating 500 draws through the multistage computational pipeline. Findings: In the reference scenario forecast, global and super-regional life expectancy increased from 2022 to 2050, but improvement was at a slower pace than in the three decades preceding the COVID-19 pandemic (beginning in 2020). Gains in future life expectancy were forecasted to be greatest in super-regions with comparatively low life expectancies (such as sub-Saharan Africa) compared with super-regions with higher life expectancies (such as the high-income super-region), leading to a trend towards convergence in life expectancy across locations between now and 2050. At the super-region level, forecasted healthy life expectancy patterns were similar to those of life expectancies. Forecasts for the reference scenario found that health will improve in the coming decades, with all-cause age-standardised DALY rates decreasing in every GBD super-region. The total DALY burden measured in counts, however, will increase in every super-region, largely a function of population ageing and growth. We also forecasted that both DALY counts and age-standardised DALY rates will continue to shift from CMNNs to NCDs, with the most pronounced shifts occurring in sub-Saharan Africa (60·1% [95% UI 56·8–63·1] of DALYs were from CMNNs in 2022 compared with 35·8% [31·0–45·0] in 2050) and south Asia (31·7% [29·2–34·1] to 15·5% [13·7–17·5]). This shift is reflected in the leading global causes of DALYs, with the top four causes in 2050 being ischaemic heart disease, stroke, diabetes, and chronic obstructive pulmonary disease, compared with 2022, with ischaemic heart disease, neonatal disorders, stroke, and lower respiratory infections at the top. The global proportion of DALYs due to YLDs likewise increased from 33·8% (27·4–40·3) to 41·1% (33·9–48·1) from 2022 to 2050, demonstrating an important shift in overall disease burden towards morbidity and away from premature death. The largest shift of this kind was forecasted for sub-Saharan Africa, from 20·1% (15·6–25·3) of DALYs due to YLDs in 2022 to 35·6% (26·5–43·0) in 2050. In the assessment of alternative future scenarios, the combined effects of the scenarios (Safer Environment, Improved Childhood Nutrition and Vaccination, and Improved Behavioural and Metabolic Risks scenarios) demonstrated an important decrease in the global burden of DALYs in 2050 of 15·4% (13·5–17·5) compared with the reference scenario, with decreases across super-regions ranging from 10·4% (9·7–11·3) in the high-income super-region to 23·9% (20·7–27·3) in north Africa and the Middle East. The Safer Environment scenario had its largest decrease in sub-Saharan Africa (5·2% [3·5–6·8]), the Improved Behavioural and Metabolic Risks scenario in north Africa and the Middle East (23·2% [20·2–26·5]), and the Improved Nutrition and Vaccination scenario in sub-Saharan Africa (2·0% [–0·6 to 3·6]). Interpretation: Globally, life expectancy and age-standardised disease burden were forecasted to improve between 2022 and 2050, with the majority of the burden continuing to shift from CMNNs to NCDs. That said, continued progress on reducing the CMNN disease burden will be dependent on maintaining investment in and policy emphasis on CMNN disease prevention and treatment. Mostly due to growth and ageing of populations, the number of deaths and DALYs due to all causes combined will generally increase. By constructing alternative future scenarios wherein certain risk exposures are eliminated by 2050, we have shown that opportunities exist to substantially improve health outcomes in the future through concerted efforts to prevent exposure to well established risk factors and to expand access to key health interventions
Numerical Investigation on a Liquid–Gas Ejector for Carbon Dioxide Removal Using Amine Solution: Hydrodynamics and Mass Transfer Evaluation
The present study investigates the hydrodynamics and mass transfer of the liquid–gas ejector using three-dimensional (air–water) and two-dimensional (CO2/air-MEA (Monoethanolamine) solution) computational fluid dynamics (CFD) modeling. For 3D simulation, validation of the CFD results of this ejector with experimental data (error less than 5%) showed high simulation accuracy. The effects of motive liquid flow rate and outlet pressure parameters on the air entrainment rate and air hold-up are also investigated. It was found that by increasing the outlet pressure by about 70% (from 3587 to 6127 Pag), the rate of gas entrainment and gas hold up decreased by about 37% and 20%, respectively. On the contrary, these parameters showed increasing behavior of about 74% and 15%, respectively, when the mass flow rate of liquid increased by about 21%. In addition, three-dimensional phenomena such as mixing shock and the location of its occurrence are examined, which is the reason for recirculation and vortex in the ejector. Next, by simulating a two-dimensional simulation and changing the inlet fluids to CO2/air-methanol amine, the ejector was designed to simultaneously increase the gas pressure and absorb carbon dioxide. A user-defined function code was used to express the mass transfer from the gas to the liquid phase. The results, in this case, showed that with increasing the outlet pressure of the ejector (from 0 to 2000 Pag), and enhancing the concentration of MEA solution (from 10% to 30%), the CO2 removal boosted from 83% to 95%. A similar behavior was shown when the L/G ratio increased from 3.5 to 5.5. This study serves as a showcase on how to do an exact design and analysis for liquid–gas ejectors in flare gas recovery systems
Numerical Investigation on a Liquid–Gas Ejector for Carbon Dioxide Removal Using Amine Solution: Hydrodynamics and Mass Transfer Evaluation
The present study investigates the hydrodynamics and mass transfer of the liquid–gas ejector using three-dimensional (air–water) and two-dimensional (CO2/air-MEA (Monoethanolamine) solution) computational fluid dynamics (CFD) modeling. For 3D simulation, validation of the CFD results of this ejector with experimental data (error less than 5%) showed high simulation accuracy. The effects of motive liquid flow rate and outlet pressure parameters on the air entrainment rate and air hold-up are also investigated. It was found that by increasing the outlet pressure by about 70% (from 3587 to 6127 Pag), the rate of gas entrainment and gas hold up decreased by about 37% and 20%, respectively. On the contrary, these parameters showed increasing behavior of about 74% and 15%, respectively, when the mass flow rate of liquid increased by about 21%. In addition, three-dimensional phenomena such as mixing shock and the location of its occurrence are examined, which is the reason for recirculation and vortex in the ejector. Next, by simulating a two-dimensional simulation and changing the inlet fluids to CO2/air-methanol amine, the ejector was designed to simultaneously increase the gas pressure and absorb carbon dioxide. A user-defined function code was used to express the mass transfer from the gas to the liquid phase. The results, in this case, showed that with increasing the outlet pressure of the ejector (from 0 to 2000 Pag), and enhancing the concentration of MEA solution (from 10% to 30%), the CO2 removal boosted from 83% to 95%. A similar behavior was shown when the L/G ratio increased from 3.5 to 5.5. This study serves as a showcase on how to do an exact design and analysis for liquid–gas ejectors in flare gas recovery systems
The Effect of Ceramic Membranes’ Structure on the Oil and Ions Removal in Pre-Treatment of the Desalter Unit Wastewater
Salts, organic materials, and hazardous materials can be found regularly in the effluent from a desalter unit of crude oil. These materials should be separated from the wastewater. Four kinds of inexpensive and innovative ceramic microfiltration membranes (mullite, mullite-alumina (MA 50%), mullite-alumina-zeolite (MAZ 20%), and mullite-zeolite (MZ 40%)) were synthesized in this research using locally available inexpensive raw materials such as kaolin clay, natural zeolite, and alpha-alumina powders. Analyses carried out on the membranes include XRD, SEM, void fraction, the average diameter of the pores, and the ability to withstand mechanical stress. Effluent from the desalter unit was synthesized in the laboratory using the salts most present in the desalter wastewater (NaCl, MgCl2, and CaCl2) and crude oil. This synthesized wastewater was treated with prepared ceramic membranes. It was discovered that different salt concentrations (0, 5000, 25,000, 50,000, 75,000, and 100,000 mg L−1) affected the permeate flux (PF), oil rejection, and ion rejection by the membrane. Results showed that in a lower concentration of salts (5000 and 25,000 mg L−1), PF of all types of ceramic membranes was increased significantly, while in the higher concentration, PF declined due to polarization concentration and high fouling effects. Oil and ion rejection was increased slightly by increasing salt dosage in wastewater due to higher ionic strength. Monovalent (Na+) and multivalent (Ca2+ and Mg2+) ion rejection was reported about 5 to 13%, and 23 to 40% respectively. Oil rejection varied from 96.2 to 99.2%
Investigation on The Effect of Paraffin content, Press Time and temperature on Practical Properties Especially Surface Roughness of Particleboard
In this investigation, the effect of paraffin content and press time and temperature on practical properties especially surface roughness of particleboard is studied. The variables such as paraffin content at 0, 1& 2 percent, press temperature at 170° and 180° C and press time of 4 and 5 minutes were investigated.
Modulus of rupture, modulus of elasticity, shear strength, water absorption and thickness swelling after 2& 24 hours soaking in water & surface roughness were measured.
The results indicate that there is no significant difference on the influence of paraffin content on either MOR & MOE of the particleboard. But increasing paraffin content decreased shear strength of panels.
However, addition of paraffin reduced water absorption and thickness swelling.
Press temperature had no significant influence on measured properties, but this variables increased surface roughness. Increasing press time, improved MOE, but showed no significant influence on other properties
Ghrelin and ghrelin/total cholesterol ratio as independent predictors for coronary artery disease: a systematic review and meta-analysis
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Ghrelin and ghrelin/total cholesterol ratio as independent predictors for coronary artery disease: a systematic review and meta-analysis
http://orcid.org/0000-0001-7611-7799Maryam Niknam1, Taraneh Liaghat2, Mehrdad Zarghami3, Mehdi Akrami2, Seyed Mehdi Shahnematollahi2, Ahmad Ahmadipour4, Fatemeh Moazzen5, http://orcid.org/0000-0002-3628-9438Sahar Soltanabadi2
Correspondence to Dr Sahar Soltanabadi, Cardiovascular Research Center, Shiraz University of Medical Sciences, Shiraz 7175735865, Iran (the Islamic Republic of); [email protected]
Abstract
The present meta-analysis aimed to summarize the available data regarding the circulating levels of ghrelin in patients with cardiovascular diseases (CVDs). A comprehensive search was performed in electronic databases including PubMed, Scopus, EMBASE, and Web of Science up to January 20, 2021. Since the circulating levels of ghrelin were measured in different units across the included studies, they were expressed as the standardized mean difference (SMD) and 95% CI (summary effect size). A random-effects model comprising the DerSimonian and Laird method was used to pool SMDs. Sixteen articles (20 studies) comprised of 1087 cases and 437 controls were included. The pooled results showed that there were no significant differences between cases and controls in terms of ghrelin levels (SMD=−0.61, 95% CI −1.38 to 0.16; p=0.120; I2=96.9%, p<0.001). The ghrelin concentrations in the CAD stratum were significantly lower than in controls, whereas they increased in other disease strata. New combined biomarkers demonstrated a significant decrease in the SMD of the ghrelin/total cholesterol (TC) ratio (−1.02; 95% CI −1.74 to –0.29, p=0.000; I2=94.5%). However, no significant differences were found in the SMD of the ghrelin/high-density lipoprotein cholesterol ratio, ghrelin/low-density lipoprotein cholesterol ratio, and ghrelin/triglyceride (TG) ratio in cases with CVDs compared with the control group. Ghrelin was associated with CAD; therefore, it may be considered a biomarker for distinguishing between patients with and without CAD. Furthermore, the ghrelin/TC ratio could be proposed as a diagnostic marker for CVD