12 research outputs found
Bone Tissue Response to Plasma Sprayed Hydroxyapatite Coatings: An In Vivo Study on Rabbit Femoral Condyles
In this study, hydroxyapatite was coated on titanium substrates by plasma spraying process. A well-known porous and lamellar microstructure was found in the lateral and outer surface of coating. The phase composition was studied by XRD and the morphological and the microstructural aspects were investigated by scanning electron and optical microscopy. The hardness of coatings and substrates was measured by Vickers indentation method. For in vivo study, rabbit condyles were exposed to two groups of coated and uncoated samples. Radiographyically, different parameters such as bone lysis, sclerosis, displacement of samples and bone resorption were taken into consideration and no statistically differences between the two groups, with no sign of infection on the edges of each hole were found. Histopathological interpretation of all coated samples indicated that the extent of callus and thickness of speculae were quite distinct from that of uncoated group. In this group, the space between implant and canal was filled up with matured connective tissues and plenty of bone speculae of woven bone in nature. However, these speculaes were thinner and immature as compared to coated samples
Bone Tissue Response to Plasma Sprayed Hydroxyapatite Coatings: An In Vivo Study on Rabbit Femoral Condyles
In this study, hydroxyapatite was coated on titanium substrates by plasma spraying process. A well-known porous and lamellar microstructure was found in the lateral and outer surface of coating. The phase composition was studied by XRD and the morphological and the microstructural aspects were investigated by scanning electron and optical microscopy. The hardness of coatings and substrates was measured by Vickers indentation method. For in vivo study, rabbit condyles were exposed to two groups of coated and uncoated samples. Radiographyically, different parameters such as bone lysis, sclerosis, displacement of samples and bone resorption were taken into consideration and no statistically differences between the two groups, with no sign of infection on the edges of each hole were found. Histopathological interpretation of all coated samples indicated that the extent of callus and thickness of speculae were quite distinct from that of uncoated group. In this group, the space between implant and canal was filled up with matured connective tissues and plenty of bone speculae of woven bone in nature. However, these speculaes were thinner and immature as compared to coated samples
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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
Electrophoretic Deposition of Hydroxyapatite: Electrophoretic deposition of hydroxyapatite
The purpose of this study was to investigate the deposition of the hydroxyapatite(HA) coating via the electrophoresis procedure. The HAdeposition was performedin an ethanol, methanol, acetone and isopropanol suspension. Methanol was foundto be the best deposition media. Among the different environmental conditions,including the encapsulation of the samples under two vacuum types of pressure(10-5-10-4and 2×10-2Torr) and also thepurge of the argon gas in the tube-likefurnace, the optimum environment was the one demonstrating the encapsulation underthe vacuum pressure of 2×10-2Torr (washing with argon gas of 99.9% purity). Afterthe examination of 3 sintering temperatures (1020, 1050 and 1100 ºC), the sinteringtemperature at 1050 ºC illustrated the most desired results. The samples sintered underthese conditions were apparently intact, most of the interfacial part of the coatingwas found to be attached to the substrate surface irregularities and no single crackswere observed
Bone Tissue Response to Plasma Sprayed Hydroxyapatite Coatings: An In Vivo Study on Rabbit Femoral Condyles: Bone tissue response to hydroxyapatite-coated Ti-6Al-4V substrates
In this study, hydroxyapatite was coated on titanium substrates by plasma spraying process. A well-known porous and lamellar microstructure was found in the lateral and outer surface of coating. The phase composition was studied by XRD and the morphological and the microstructural aspects were investigated by scanning electron and optical microscopy. The hardness of coatings and substrates was measured by Vickers indentation method. For in vivo study, rabbit condyles were exposed to two groups of coated and uncoated samples. Radiographyically, different parameters such as bone lysis, sclerosis, displacement of samples and bone resorption were taken into consideration and no statistically differences between the two groups, with no sign of infection on the edges of each hole were found. Histopathological interpretation of all coated samples indicated that the extent of callus and thickness of speculae were quite distinct from that of uncoated group. In this group, the space between implant and canal was filled up with matured connective tissues and plenty of bone speculae of woven bone in nature. However, these speculaes were thinner and immature as compared to coated samples
Discovery of Leptulipin, a New Anticancer Protein from the Iranian Scorpion, Hemiscorpius lepturus
International audienceCancer is one of the leading causes of mortality in the world. Unfortunately, the present anticancer chemotherapeutics display high cytotoxicity. Accordingly, the discovery of new anticancer agents with lower side effects is highly necessitated. This study aimed to discover an anticancer compound from Hemiscorpius lepturus scorpion venom. Bioactivity-guided chromatography was performed to isolate an active compound against colon and breast cancer cell lines. 2D electrophoresis and MALDI-TOF were performed to identify the molecule. A partial protein sequence was obtained by mass spectrometry, while the full-length was deciphered using a cDNA library of the venom gland by bioinformatics analyses and was designated as leptulipin. The gene was cloned in pET-26b, expressed, and purified. The anticancer effect and mechanism action of leptulipin were evaluated by MTT, apoptosis, and cell cycle assays, as well as by gene expression analysis of apoptosis-related genes. The treated cells displayed inhibition of cell proliferation, altered morphology, DNA fragmentation, and cell cycle arrest. Furthermore, the treated cells showed a decrease in BCL-2 expression and an increase in Bax and Caspase 9 genes. In this study, we discovered a new anticancer protein from H. lepturus scorpion venom. Leptulipin showed significant anticancer activity against breast and colon cancer cell lines
The effect of omega-3 fatty acid supplementation on clinical and biochemical parameters of critically ill patients with COVID-19: a randomized clinical trial
Nanocrystalline copper doped zinc oxide produced from copper doped zinc hydroxide nitrate as a layered precursor
Physicochemical identity and charge storage properties of battery-type nickel oxide material and its composites with activated carbon
Global, regional, and national burden of diabetes from 1990 to 2021, with projections of prevalence to 2050: a systematic analysis for the Global Burden of Disease Study 2021
Background: Diabetes is one of the leading causes of death and disability worldwide, and affects people regardless of country, age group, or sex. Using the most recent evidentiary and analytical framework from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD), we produced location-specific, age-specific, and sex-specific estimates of diabetes prevalence and burden from 1990 to 2021, the proportion of type 1 and type 2 diabetes in 2021, the proportion of the type 2 diabetes burden attributable to selected risk factors, and projections of diabetes prevalence through 2050. Methods: Estimates of diabetes prevalence and burden were computed in 204 countries and territories, across 25 age groups, for males and females separately and combined; these estimates comprised lost years of healthy life, measured in disability-adjusted life-years (DALYs; defined as the sum of years of life lost [YLLs] and years lived with disability [YLDs]). We used the Cause of Death Ensemble model (CODEm) approach to estimate deaths due to diabetes, incorporating 25 666 location-years of data from vital registration and verbal autopsy reports in separate total (including both type 1 and type 2 diabetes) and type-specific models. Other forms of diabetes, including gestational and monogenic diabetes, were not explicitly modelled. Total and type 1 diabetes prevalence was estimated by use of a Bayesian meta-regression modelling tool, DisMod-MR 2.1, to analyse 1527 location-years of data from the scientific literature, survey microdata, and insurance claims; type 2 diabetes estimates were computed by subtracting type 1 diabetes from total estimates. Mortality and prevalence estimates, along with standard life expectancy and disability weights, were used to calculate YLLs, YLDs, and DALYs. When appropriate, we extrapolated estimates to a hypothetical population with a standardised age structure to allow comparison in populations with different age structures. We used the comparative risk assessment framework to estimate the risk-attributable type 2 diabetes burden for 16 risk factors falling under risk categories including environmental and occupational factors, tobacco use, high alcohol use, high body-mass index (BMI), dietary factors, and low physical activity. Using a regression framework, we forecast type 1 and type 2 diabetes prevalence through 2050 with Socio-demographic Index (SDI) and high BMI as predictors, respectively. Findings: In 2021, there were 529 million (95% uncertainty interval [UI] 500-564) people living with diabetes worldwide, and the global age-standardised total diabetes prevalence was 6·1% (5·8-6·5). At the super-region level, the highest age-standardised rates were observed in north Africa and the Middle East (9·3% [8·7-9·9]) and, at the regional level, in Oceania (12·3% [11·5-13·0]). Nationally, Qatar had the world's highest age-specific prevalence of diabetes, at 76·1% (73·1-79·5) in individuals aged 75-79 years. Total diabetes prevalence-especially among older adults-primarily reflects type 2 diabetes, which in 2021 accounted for 96·0% (95·1-96·8) of diabetes cases and 95·4% (94·9-95·9) of diabetes DALYs worldwide. In 2021, 52·2% (25·5-71·8) of global type 2 diabetes DALYs were attributable to high BMI. The contribution of high BMI to type 2 diabetes DALYs rose by 24·3% (18·5-30·4) worldwide between 1990 and 2021. By 2050, more than 1·31 billion (1·22-1·39) people are projected to have diabetes, with expected age-standardised total diabetes prevalence rates greater than 10% in two super-regions: 16·8% (16·1-17·6) in north Africa and the Middle East and 11·3% (10·8-11·9) in Latin America and Caribbean. By 2050, 89 (43·6%) of 204 countries and territories will have an age-standardised rate greater than 10%. Interpretation: Diabetes remains a substantial public health issue. Type 2 diabetes, which makes up the bulk of diabetes cases, is largely preventable and, in some cases, potentially reversible if identified and managed early in the disease course. However, all evidence indicates that diabetes prevalence is increasing worldwide, primarily due to a rise in obesity caused by multiple factors. Preventing and controlling type 2 diabetes remains an ongoing challenge. It is essential to better understand disparities in risk factor profiles and diabetes burden across populations, to inform strategies to successfully control diabetes risk factors within the context of multiple and complex drivers. Funding: Bill & Melinda Gates Foundation