Poly (ɛ-caprolactone) nanofibrous ring surrounding a polyvinyl alcohol hydrogel for the development of a biocompatible two-part artificial cornea

The study aimed to fabricate and characterize a 2-part artificial cornea as a substitute for penetrating keratoplasty in patients with corneal blindness. The peripheral part of the artificial cornea consisted of plasma-treated electrospun poly (ɛ-caprolactone) (PCL) nanofibers, which were attached to a hydrogel disc of polyvinyl alcohol (PVA) as a central optical part. The physical properties of the prepared artificial cornea, including morphology, mechanical properties, light transmittance, and contact angle, were assessed. Cell attachment and proliferation studies were performed on rabbit limbal stem cells. The SEM image of the polymeric system showed that the peripheral part formed a highly porous scaffold that could facilitate tissue biointegration. Assessment of the mechanical properties of the peripheral nanofibrous part and the hydrogel optical part showed suitable elasticity. Young’s modulus values of the electrospun PCL skirt and PVA hydrogel core were 7.5 and 5.3 MPa, respectively, which is in line with the elasticity range of natural human cornea (0.3–7 MPa). The light transmittance of the central part was >85% when measured in the 400–800 nm wavelength range. The plasma-treated PCL nanofibrous scaffold promoted limbal stem cell adhesion and proliferation within 10 days. These results confirmed that the polymeric artificial cornea showed suitable physical properties and good biocompatibility and epithelialization ability

Association between the rs2241883 polymorphism of the fatty acid-binding protein-1 (FABP1) gene and obesity in a population of MASHAD study cohort

Funding Information: We would like to thank Mashhad University of Medical Sciences Research Council for their financial supports.Peer reviewedPublisher PD

The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

Relationship between serum nitric oxide of patients with thyroid disorders and metabolic syndrome indices and nitrate concentration of water

Abstract This case–control study aimed to assess the effect of drinking water nitrate on serum nitric oxide concentration and the risk of metabolic syndrome (MetS) in the population in the Middle East. The study included 50 control and 50 thyroid disorder cases who were referred to two medical centers in 2021. In this study, serum nitric oxide concentration, drinking water nitrate, and metabolic syndrome components were measured in the two groups. The results showed there was a statistically significant difference between serum NO in the case and control groups (p-value < 0.001). There was a positive correlation between the concentration of nitrate in drinking water and serum nitric oxide in the case and control groups; however, this relationship was not significant statistically. A statistically significant difference was found between serum nitric oxide and systolic blood pressure in the cases (p-value < 0.05), but there was no significant difference between MetS and nitric oxide. Therefore, we concluded that the relationship between nitric oxide and nitrate in consuming water should be determined in thyroid patients. In addition to their water consumption, it is better to study the nitrate of foods, especially vegetables

The prevalence and determinants of pterygium in rural areas

Purpose: To evaluate the prevalence of pterygium and its determinants in the underserved, rural population of Iran. Methods: In this cross-sectional study of 3851 selected individuals, 86.5% participated in the study, and the prevalence of pterygium was evaluated in 3312 participants. A number of villages were selected from the north and south of Iran using multistage cluster sampling. Pterygium was diagnosed by the ophthalmologist using slit-lamp examination. Results: The mean age of the study participants was 37.3 ± 21.4 years (2–93 years), and 56.3% (n = 1865) of them were women. The prevalence of pterygium was 13.11% [95%confidence interval (CI):11.75–14.47]. The prevalence of pterygium was 14.99 (95%CI:12.79–17.19) in men and 12.07 (95%CI:10.3–13.84) in women. Pterygium was not seen in children below the age of 5 years. The prevalence of pterygium increased linearly with age; the lowest and highest prevalence of pterygium was observed in the age group 5–20 years (0.19%) and 61–70 years (28.57%). Evaluation of the relationship between pterygium with age, sex, educational level, and place of living using a multiple model showed that age, living in the south of Iran, and low educational level were correlated with pterygium. Conclusion: The prevalence of pterygium was significantly higher in Iranian villages when compared with the results of previous studies. This finding may represent the effect of a rural lifestyle and its risk factors. Keywords: Pterygium, Prevalence, Rural population, Middle Eas

Frequency of Beta-globin gene mutations in beta-thalassemia patients from east of Mazandaran

(Received 6 Aug, 2008; Accepted 3 Dec, 2008) Abstract Background and purpose: Beta-thalassemia is the most common inherited disorder in the world, especially in Iran. According to Iranian thalassemia society registry, 18616 thalassemia patients now living in Iran, which Mazandaran and Fars provinces have the most patients. Previous reports have shown that the frequency of b-thalassemia carriers is more than 10% in Mazandaran province. Although b-thalassemia is very heterogenous in the molecular level, but in each population, 5 to 10 mutations are more common. In this research common mutation in eastern area of Mazadaran province was investigated. Materials and methods: 5 to 10 ml peripheral blood samples were collected from volunteer patients who were referred to Boali Sina Hospital in Sari. DNA was extracted from blood, then 20 different mutations were screened and detected using two different methods, ARMS-PCR and Reverse-Dot Blot in Thalassemia Research Center in Sari and Amir Kola Thalassemia Center. Results: From 240 chromosomes investigated in 120 b-thalassemia patients in total, 96.25% mutations were identified. 13 different mutations were identified from 231 chromosomes. Among different mutations investigated, IVSII-1G>A was detected as the most common with frequency of 68/3%, which was homozygous in 64 individuals (53/3%) and compound heterozygous with other mutations in 34 individuals (28/3%) respectively. Mutations C8(-AA), codon22(G>A)/ FSC 22/23/24(-7bp), codon 30(G>A), and IVSII-1G>A were identified in 83% of chromosomes which were studied (200 chromosomes from 240). Conclusion: Mutation IVSII-1G>A is the most common mutation in northern provinces (Gilan, mazandaran, Golestan) in recent study. Also, comparison of these results with the similar finding from other provinces showed that the distributions of mutations in the northern area are different with northwest, south or southeast of the country

Amniotic Membrane Extract Preparation: What is the Best Method?

Purpose: To compare different preparation methods for a suitable amniotic membrane (AM) extract containing a given amount of growth factors. Methods: In this interventional case series, we dissected the AM from eight placentas within 24 hours after delivery, under clean conditions. After washing and mixing, AM extracts (AMEs) were prepared using pulverization and homogenization methods, and different processing and storing conditions. Main outcome measures were the amount of added protease inhibitor (PI), the relative centrifugal force (g), in-process temperature, repeated extraction times, drying percentage, repeated pulverization times, and the effect of filtering with 0.2 μm filters. Extract samples were preserved at different temperature and time parameters, and analyzed for hepatic growth factor (HGF) and total protein using ELISA and calorimetric methods, respectively. Results: The extracted HGF was 20% higher with pulverization as compared to homogenization, and increased by increasing the PI to 5.0 μl/g of dried AM. Repeating centrifugation up to 3 times almost doubled the extracted HGF and protein. Storing the AME at −170° for 6 months caused a 50% drop in the level of HGF and protein. Other studied parameters showed no significant effect on the extracted amount of HGF or total protein. Conclusion: Appropriate extraction methods with an adequate amount of PI increases the level of extractable components from harvested AMs. To achieve the maximal therapeutic effects of AMEs, it is necessary to consider the half-life of its bioactive components