41 research outputs found

    Some classes of perfect strongly annihilating-ideal graphs associated with commutative rings

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    summary:Let RR be a commutative ring with identity and A(R)A(R) be the set of ideals with nonzero annihilator. The strongly annihilating-ideal graph of RR is defined as the graph SAG(R){\rm SAG}(R) with the vertex set A(R)=A(R){0}A(R)^*=A(R)\setminus\{0\} and two distinct vertices II and JJ are adjacent if and only if IAnn(J)(0)I\cap {\rm Ann}(J)\neq (0) and JAnn(I)(0)J\cap {\rm Ann}(I)\neq (0). In this paper, the perfectness of SAG(R){\rm SAG}(R) for some classes of rings RR is investigated

    Sumatriptan effects on morphine-induced antinociceptive tolerance and physical dependence: The role of nitric oxide

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    Sumatriptan, a 5HT (5-hydroxytryptamine)1B/1D receptor agonist, showed neuroprotection in different studies. The aim of the present study was to investigate the effect of sumatriptan on morphine-induced antinociceptive tolerance and physical dependence. We also investigated the possible role of nitric oxide (NO) on sumatriptan effects. Tolerance was induced by morphine injection (50, 50, 75 mg/kg) three times daily for five days. Antinociceptive latency after acute and chronic treatment with sumatriptan (0.001, 0.01, 0.1 and 1 mg/kg) was measured by hot plate test in morphine-dependent animals. To investigate the possible involvement of NO, different isoforms of nitric oxide synthase (NOS) inhibitors including L-NAME, aminoguanidine and 7-nitroindazole were co-administered with sumatriptan. Nitrite level in mice hippocampus was quantified by Griess method. To examine the role of sumatriptan on physical dependence, three parameters of withdrawal signs were recorded after injection of naloxone (4 mg/kg). Acute treatment with sumatriptan (0.01, 0.1 and 1 mg/kg) attenuated the antinociceptive tolerance (P < 0.001). Chronic injection of sumatriptan (0.001, 0.01 and 0.1 mg/kg), as well, decreased the antinociceptive tolerance (P < 0.001). Moreover, co-administration of NOS inhibitors prevented the effects of sumatriptan. Sumatriptan significantly increased the level of nitrite only after chronic administration. Sumatriptan administration showed no alteration in naloxone-precipitated withdrawal signs. Acute and chronic administration of sumatriptan attenuated morphine antinociceptive tolerance; at least in chronic phase via nitrergic pathway. Our data did not support beneficial effects of sumatriptan on morphineinduced physical dependence in mice

    Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

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    Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods: GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings: Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation: As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and developm nt investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens

    Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries and territories, 1950-2019 : a comprehensive demographic analysis for the Global Burden of Disease Study 2019

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    Background: Accurate and up-to-date assessment of demographic metrics is crucial for understanding a wide range of social, economic, and public health issues that affect populations worldwide. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 produced updated and comprehensive demographic assessments of the key indicators of fertility, mortality, migration, and population for 204 countries and territories and selected subnational locations from 1950 to 2019. Methods: 8078 country-years of vital registration and sample registration data, 938 surveys, 349 censuses, and 238 other sources were identified and used to estimate age-specific fertility. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate age-specific fertility rates for 5-year age groups between ages 15 and 49 years. With extensions to age groups 10–14 and 50–54 years, the total fertility rate (TFR) was then aggregated using the estimated age-specific fertility between ages 10 and 54 years. 7417 sources were used for under-5 mortality estimation and 7355 for adult mortality. ST-GPR was used to synthesise data sources after correction for known biases. Adult mortality was measured as the probability of death between ages 15 and 60 years based on vital registration, sample registration, and sibling histories, and was also estimated using ST-GPR. HIV-free life tables were then estimated using estimates of under-5 and adult mortality rates using a relational model life table system created for GBD, which closely tracks observed age-specific mortality rates from complete vital registration when available. Independent estimates of HIV-specific mortality generated by an epidemiological analysis of HIV prevalence surveys and antenatal clinic serosurveillance and other sources were incorporated into the estimates in countries with large epidemics. Annual and single-year age estimates of net migration and population for each country and territory were generated using a Bayesian hierarchical cohort component model that analysed estimated age-specific fertility and mortality rates along with 1250 censuses and 747 population registry years. We classified location-years into seven categories on the basis of the natural rate of increase in population (calculated by subtracting the crude death rate from the crude birth rate) and the net migration rate. We computed healthy life expectancy (HALE) using years lived with disability (YLDs) per capita, life tables, and standard demographic methods. Uncertainty was propagated throughout the demographic estimation process, including fertility, mortality, and population, with 1000 draw-level estimates produced for each metric. Findings: The global TFR decreased from 2·72 (95% uncertainty interval [UI] 2·66–2·79) in 2000 to 2·31 (2·17–2·46) in 2019. Global annual livebirths increased from 134·5 million (131·5–137·8) in 2000 to a peak of 139·6 million (133·0–146·9) in 2016. Global livebirths then declined to 135·3 million (127·2–144·1) in 2019. Of the 204 countries and territories included in this study, in 2019, 102 had a TFR lower than 2·1, which is considered a good approximation of replacement-level fertility. All countries in sub-Saharan Africa had TFRs above replacement level in 2019 and accounted for 27·1% (95% UI 26·4–27·8) of global livebirths. Global life expectancy at birth increased from 67·2 years (95% UI 66·8–67·6) in 2000 to 73·5 years (72·8–74·3) in 2019. The total number of deaths increased from 50·7 million (49·5–51·9) in 2000 to 56·5 million (53·7–59·2) in 2019. Under-5 deaths declined from 9·6 million (9·1–10·3) in 2000 to 5·0 million (4·3–6·0) in 2019. Global population increased by 25·7%, from 6·2 billion (6·0–6·3) in 2000 to 7·7 billion (7·5–8·0) in 2019. In 2019, 34 countries had negative natural rates of increase; in 17 of these, the population declined because immigration was not sufficient to counteract the negative rate of decline. Globally, HALE increased from 58·6 years (56·1–60·8) in 2000 to 63·5 years (60·8–66·1) in 2019. HALE increased in 202 of 204 countries and territories between 2000 and 2019

    Design of eudragit RL nanoparticles by nanoemulsion method as carriers for ophthalmic drug delivery of ketotifen fumarate

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    Objective(s): Ketotifen fumarate (KF) is a selective and noncompetitive histamine antagonist (H1-receptor) that is used topically in the treatment of allergic conditions of rhinitis and conjunctivitis. The aim of this study was to formulate and improve an ophthalmic delivery system of KF.Ocular nanoparticles were prepared with the objective of reducing the frequency of administration and obtaining controlled release to improve the anti-inflammatory drug delivery. Materials and Methods:In the present study, ocular KF loaded Eudragit RL 100 nanoparticles were prepared using O/W solvent diffusion method. The nanoparticles were evaluated for particle size, entrapment efficiency, surface morphology, X-ray diffraction (XRD), Fourier transform spectroscopy (FTIR), and differential scanning calorimetry (DSC). In vitro release and permeation studies were also carried out on nanoparticles. Results: An average size range of 182 to 314.30 nm in diameter was obtained and encapsulation efficiency up to 95.0% was observed for all the formulations. Drug release for all formulations after 24 hr was between 65.51% and 88.82% indicating effective controlled release property of KF. The mechanism of drug release for best formulation was found to be fickian diffusion mechanism. KF nanoparticles containing high polymer concentration (1:15) presented a faster drug release and a higher drug penetration; on the contrary, nanoparticles containing low polymer concentration (1:7.5) were able to give a more sustained release of the drug and thus a slower KF permeation through the cornea. Conclusion: The study revealed that KF NPs were capable of releasing the drug for a prolonged period of time and increasing the ocular bioavailability

    The Influence of Lateral and Supine Position on Bacterial Colonization of Endotracheal Tube in Neonates Admitted to Neonatal Intensive Care Unit

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    Objective: Recent data suggest that during mechanical ventilation, lateral patient position (in which the endotracheal tube is horizontal) decreases the incidence of bacterial colonization of ventilated neonates. The objective of this study was to evaluate the influence of lateral and supine position on bacterial colonization of endotracheal tube in neonates. Methods: We conducted a prospective, randomized, clinical trial with 31 intubated neonates (intubated within 48 hours after birth); sixteen neonates were positioned supine (supine group), and fifteen were maintained in the lateral position (lateral group).Tracheal aspirates were cultured in second and fifth days of mechanical ventilation. Data were analyzed with SPSS version 16. Findings: In the second day of ventilation, positive cultures were recognized in 6.2% of supine group and 6.7% of lateral group. After 5 days, tracheal cultures were positive in 25% (4 neonates) of supine group and 13.3% (2 neonates) of lateral group that wasn't statistically significant (P=0.9 in second day and P=0.9 in the fifth day). The most common organisms isolated from tracheal aspirates were Gram-negative rods (Klebsiella). Conclusion: Since respiratory contamination is very common among ventilated neonates and the effect of lateral position on bacterial colonization of endotracheal tubes of intubated neonates wasn't established in our study, further studies are required to suggest ways to decrease bacterial colonization of intubated neonates
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