14 research outputs found

    Cytochrome P450 1B1 and 12/15 Lipoxygenase Interaction in Paraventricular Nucleus in Angiotensin II-induced Hypertension in Females

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    Background: Angiotensin (Ang) II releases arachidonic acid (AA) from tissue phospholipids that is metabolized by 12/15-lipoxygenase (ALOX15) generating 12(S)- and 15(S)-hydroxyeicosatetraenoic acid (HETE) which have been implicated in cardiovascular and renal diseases. This study was conducted to investigate a) the contribution of ALOX15 to Ang II-induced hypertension and associated pathogenesis in female mice, and b) the interaction between the cytochrome P450 (CYP)1B1-generated metabolite of 17β-estradiol (E2) (2-methoxyestradiol, 2-ME) and ALOX15 in the paraventricular nucleus (PVN) as a mechanism that protects against Ang II-induced hypertension and its associated pathogenesis in female mice. Methods: Experiments were conducted in intact and ovariectomized (OVX) wild type (WT), alox15 knockout (ALOX15KO) and CYP1B1KO female mice. Ang II (700 ng/kg/min) was infused subcutaneously by osmotic pumps for 2 weeks evaluation of hypertension and associated pathogenesis. Blood pressure (BP) was measured by tail-cuff and confirmed by radiotelemetry. Adenoviral probes including adenovirus (Ad)-green fluorescence (GFP)-ALOX15-short hairpin (sh)RNA, Ad-GFP-ALOX15-DNA, and their respective controls Ad-scrambled shRNA and Ad-GFP-DNA, 12(S)-HETE and 2-ME were injected in the brain using stereotaxic technique, either selectively in PVN or intracerebroventricularly via ICV cannula implanted in the right lateral ventricle to study their roles on Ang II-induced hypertension. Histological, immunohistochemical, and fluorescence microscopy and biochemical techniques were employed to determine the pathophysiological changes in tissues. ELISA was used for the analysis of sex steroids and eicosanoids. Results: Our results demonstrate that the effects of Ang II to increase BP, impair autonomic function and increase renal reactive oxygen species (ROS) production and plasma 12(S)-HETE but not 15(S)-HETE level without altering renal function in intact WT mice were exacerbated in OVX-WT mice. Ang II also increased renal alox15 mRNA, urine 12(S)-HETE, water intake, urine output, decreased osmolality, increased urinary excretion of vasopressin prosegment copeptin, protein/creatinine ratio, and caused renal hypertrophy, fibrosis, and inflammation in OVX-WT mice. These effects of Ang II were attenuated in ALOX15KO mice. Moreover, the Ang II-induced hypertension that was also exaggerated in intact CYP1B1KO mice compared to WT mice was minimized by selective alox15 gene knockdown in PVN by transduction with Ad-ALOX15-shRNA and the restoration of Ang II-induced hypertension by selective reconstitution of alox15 gene in PVN by transduction with Ad-ALOX15-DNA in intact ALOX15KO mice was further exacerbated in OVX-ALOX15KO mice. Furthermore, ICV-12(S)-HETE that restored Ang II-induced increase in BP, impairment of autonomic function, neuroinflammation and renal pathogenesis in intact ALOX15KO mice, further exacerbated these effects of Ang II in OVX-ALOX15KO mice. Finally, ICV-2-ME that reduced the alox15 mRNA expression and 12(S)-HETE content in PVN minimized the hypertensive effects of Ang II, including BP, autonomic impairment, neuroinflammation and renal pathogenesis in OVX-ALOX15KO with the restoration of alox15 gene in PVN by transduction ICV with Ad-ALOX15-DNA. Conclusion: These data suggest that 17β-estradiol plays a critical role in female mice in protecting against Ang II-induced hypertension and associated pathogenesis, most likely via inhibition of ALOX15 activation and reduced production of 12(S)-HETE in the PVN. Therefore, the selective inhibitors of ALOX15 or 12(S)-HETE receptor antagonists could be useful for treating hypertension and its pathogenesis in postmenopausal, hypoestrogenic women or females with ovarian failure. These data also elucidate how drugs that inhibit CYP1B1 activity can be beneficial for treating hypertension and its pathogenesis in males but can be detrimental in females. The effect of alox15 gene polymorphism in pre-and postmenopausal females to determine its impact on the contribution of AA-ALOX15 derived 12(S)-HETE in hypertension and its pathogenesis is also warranted

    Detrimental orofacial manifestations of dengue and dengue hemorrhagic fever clinical case series, review of the causes, complications, and vaccine strategies

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    It is estimated that there are about 10% of cases that involve oral mucosa in patients with dengue hemorrhagic fever (HF), and even less number of cases in dengue fever (DF) has been reported. This leads to a lack of future investigation. Aims and objectivesThis review intends to enhance the understanding of the epidemiology, clinical features involving the oral manifestations, and treatment of dengue disease. Design and Methods Several search engines, including PubMed, World Health Organization (WHO), and Pan American Health Organization (PAHO) websites were utilized for the literature search using the terms dengue and dengue shock syndrome.Results Dengue is a major arthropod-borne viral disease of humans. Its presentation is protean and varies from an undifferentiated viral syndrome to viral HF and severe shock. The early diagnosis of the oral manifestations, hemorrhagic, or mucocutaneous, may lead to timely clinical evaluation of the patient with signs and symptoms suggestive of dengue viral infection.Conclusion The specific therapy for dengue infections is still undiscovered. Proper care, including vector control and prevention of mosquito bites, may be beneficial. However, the role of dental professionals and general practitioners is important in identifying the oral manifestations of dengue viral infection and providing specific diagnosis and effective treatment to the patients

    Stock Liquidity and Firm Value: The Mediating Role of Capital Structure

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    Despite the substantial volume of research on the direct relationship between stock liquidity and firm value, no agreement has been reached on this nexus. This relationship may be influenced by some other intervening factors which have not been captured in the empirical studies. The present study aims to explore the link between stock liquidity and firm value and empirically tests the mediating role of capital structure on this relationship in the Indian context. Using sample data from 97 National Stock Exchange (NSE) listed top non-financial firms from 2010 to 2019 and adopting the Baron and Kenny approach, the results show that higher stock liquidity leads to a greater firm value. Furthermore, firms with liquid stocks are found to have significantly lower leverage. The results also confirm that capital structure fully mediates the relationship between stock liquidity and firm value. The empirical findings have important managerial implications when it comes to devising policies to maximise firms’ value

    Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

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    BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed

    Zika virus diseases – The new face of an ancient enemy as global public health emergency (2016): Brief review and recent updates

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    Zika virus (ZIKV) disease is caused by a virus transmitted by Aedes mosquito. It presents as flu-like symptoms lasting for 5–7 days and shows potential association with neurological and autoimmune complications such as congenital microcephaly and adult paralysis disorder, Guillain–Barré syndrome. Treatment measures are conservative as the disease is self-limiting. ZIKV earlier affected several tropical regions of Africa and Asia from 1951 to 2006. Subsequently, it moved out from these regions to land as outbreaks in Yap Island, French Polynesia, South America, and most recently in Brazil. The WHO declared it as an international public health emergency in 2016 and an extraordinary event with recommendations for improving communications, tightening vigil on ZIKV infections, and improving mosquito control measures. The authors in this article aim to briefly discuss ZIKV infection, its epidemiology, clinical manifestations, management, and prevention

    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

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    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

    Global fertility in 204 countries and territories, 1950–2021, with forecasts to 2100: a comprehensive demographic analysis for the Global Burden of Disease Study 2021

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    BackgroundAccurate assessments of current and future fertility—including overall trends and changing population age structures across countries and regions—are essential to help plan for the profound social, economic, environmental, and geopolitical challenges that these changes will bring. Estimates and projections of fertility are necessary to inform policies involving resource and health-care needs, labour supply, education, gender equality, and family planning and support. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 produced up-to-date and comprehensive demographic assessments of key fertility indicators at global, regional, and national levels from 1950 to 2021 and forecast fertility metrics to 2100 based on a reference scenario and key policy-dependent alternative scenarios. MethodsTo estimate fertility indicators from 1950 to 2021, mixed-effects regression models and spatiotemporal Gaussian process regression were used to synthesise data from 8709 country-years of vital and sample registrations, 1455 surveys and censuses, and 150 other sources, and to generate age-specific fertility rates (ASFRs) for 5-year age groups from age 10 years to 54 years. ASFRs were summed across age groups to produce estimates of total fertility rate (TFR). Livebirths were calculated by multiplying ASFR and age-specific female population, then summing across ages 10–54 years. To forecast future fertility up to 2100, our Institute for Health Metrics and Evaluation (IHME) forecasting model was based on projections of completed cohort fertility at age 50 years (CCF50; the average number of children born over time to females from a specified birth cohort), which yields more stable and accurate measures of fertility than directly modelling TFR. CCF50 was modelled using an ensemble approach in which three sub-models (with two, three, and four covariates variously consisting of female educational attainment, contraceptive met need, population density in habitable areas, and under-5 mortality) were given equal weights, and analyses were conducted utilising the MR-BRT (meta-regression—Bayesian, regularised, trimmed) tool. To capture time-series trends in CCF50 not explained by these covariates, we used a first-order autoregressive model on the residual term. CCF50 as a proportion of each 5-year ASFR was predicted using a linear mixed-effects model with fixed-effects covariates (female educational attainment and contraceptive met need) and random intercepts for geographical regions. Projected TFRs were then computed for each calendar year as the sum of single-year ASFRs across age groups. The reference forecast is our estimate of the most likely fertility future given the model, past fertility, forecasts of covariates, and historical relationships between covariates and fertility. We additionally produced forecasts for multiple alternative scenarios in each location: the UN Sustainable Development Goal (SDG) for education is achieved by 2030; the contraceptive met need SDG is achieved by 2030; pro-natal policies are enacted to create supportive environments for those who give birth; and the previous three scenarios combined. Uncertainty from past data inputs and model estimation was propagated throughout analyses by taking 1000 draws for past and present fertility estimates and 500 draws for future forecasts from the estimated distribution for each metric, with 95% uncertainty intervals (UIs) given as the 2·5 and 97·5 percentiles of the draws. To evaluate the forecasting performance of our model and others, we computed skill values—a metric assessing gain in forecasting accuracy—by comparing predicted versus observed ASFRs from the past 15 years (2007–21). A positive skill metric indicates that the model being evaluated performs better than the baseline model (here, a simplified model holding 2007 values constant in the future), and a negative metric indicates that the evaluated model performs worse than baseline. FindingsDuring the period from 1950 to 2021, global TFR more than halved, from 4·84 (95% UI 4·63–5·06) to 2·23 (2·09–2·38). Global annual livebirths peaked in 2016 at 142 million (95% UI 137–147), declining to 129 million (121–138) in 2021. Fertility rates declined in all countries and territories since 1950, with TFR remaining above 2·1—canonically considered replacement-level fertility—in 94 (46·1%) countries and territories in 2021. This included 44 of 46 countries in sub-Saharan Africa, which was the super-region with the largest share of livebirths in 2021 (29·2% [28·7–29·6]). 47 countries and territories in which lowest estimated fertility between 1950 and 2021 was below replacement experienced one or more subsequent years with higher fertility; only three of these locations rebounded above replacement levels. Future fertility rates were projected to continue to decline worldwide, reaching a global TFR of 1·83 (1·59–2·08) in 2050 and 1·59 (1·25–1·96) in 2100 under the reference scenario. The number of countries and territories with fertility rates remaining above replacement was forecast to be 49 (24·0%) in 2050 and only six (2·9%) in 2100, with three of these six countries included in the 2021 World Bank-defined low-income group, all located in the GBD super-region of sub-Saharan Africa. The proportion of livebirths occurring in sub-Saharan Africa was forecast to increase to more than half of the world's livebirths in 2100, to 41·3% (39·6–43·1) in 2050 and 54·3% (47·1–59·5) in 2100. The share of livebirths was projected to decline between 2021 and 2100 in most of the six other super-regions—decreasing, for example, in south Asia from 24·8% (23·7–25·8) in 2021 to 16·7% (14·3–19·1) in 2050 and 7·1% (4·4–10·1) in 2100—but was forecast to increase modestly in the north Africa and Middle East and high-income super-regions. Forecast estimates for the alternative combined scenario suggest that meeting SDG targets for education and contraceptive met need, as well as implementing pro-natal policies, would result in global TFRs of 1·65 (1·40–1·92) in 2050 and 1·62 (1·35–1·95) in 2100. The forecasting skill metric values for the IHME model were positive across all age groups, indicating that the model is better than the constant prediction. InterpretationFertility is declining globally, with rates in more than half of all countries and territories in 2021 below replacement level. Trends since 2000 show considerable heterogeneity in the steepness of declines, and only a small number of countries experienced even a slight fertility rebound after their lowest observed rate, with none reaching replacement level. Additionally, the distribution of livebirths across the globe is shifting, with a greater proportion occurring in the lowest-income countries. Future fertility rates will continue to decline worldwide and will remain low even under successful implementation of pro-natal policies. These changes will have far-reaching economic and societal consequences due to ageing populations and declining workforces in higher-income countries, combined with an increasing share of livebirths among the already poorest regions of the world. FundingBill & Melinda Gates Foundation

    Global Burden of Cardiovascular Diseases and Risks, 1990-2022

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