21 research outputs found
Dengue Virus Inhibits Immune Responses in Aedes aegypti Cells
The ability of many viruses to manipulate the host antiviral immune response often results in complex host-pathogen interactions. In order to study the interaction of dengue virus (DENV) with the Aedes aegypti immune response, we have characterized the DENV infection-responsive transcriptome of the immune-competent A. aegypti cell line Aag2. As in mosquitoes, DENV infection transcriptionally activated the cell line Toll pathway and a variety of cellular physiological systems. Most notably, however, DENV infection down-regulated the expression levels of numerous immune signaling molecules and antimicrobial peptides (AMPs). Functional assays showed that transcriptional induction of AMPs from the Toll and IMD pathways in response to bacterial challenge is impaired in DENV-infected cells. In addition, Escherichia coli, a Gram-negative bacteria species, grew better when co-cultured with DENV-infected cells than with uninfected cells, suggesting a decreased production of AMPs from the IMD pathway in virus-infected cells. Pre-stimulation of the cell line with Gram-positive bacteria prior to DENV infection had no effect on DENV titers, while pre-stimulation with Gram-negative bacteria resulted in an increase in DENV titers. These results indicate that DENV is capable of actively suppressing immune responses in the cells it infects, a phenomenon that may have important consequences for virus transmission and insect physiology
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Global burden of peripheral artery disease and its risk factors, 1990â2019: a systematic analysis for the Global Burden of Disease Study 2019
Background
Peripheral artery disease is a growing public health problem. We aimed to estimate the global disease burden of peripheral artery disease, its risk factors, and temporospatial trends to inform policy and public measures.
Methods
Data on peripheral artery disease were modelled using the Global Burden of Disease, Injuries, and Risk Factors Study (GBD) 2019 database. Prevalence, disability-adjusted life years (DALYs), and mortality estimates of peripheral artery disease were extracted from GBD 2019. Total DALYs and age-standardised DALY rate of peripheral artery disease attributed to modifiable risk factors were also assessed.
Findings
In 2019, the number of people aged 40 years and older with peripheral artery disease was 113 million (95% uncertainty interval [UI] 99·2â128·4), with a global prevalence of 1·52% (95% UI 1·33â1·72), of which 42·6% was in countries with low to middle Socio-demographic Index (SDI). The global prevalence of peripheral artery disease was higher in older people, (14·91% [12·41â17·87] in those aged 80â84 years), and was generally higher in females than in males. Globally, the total number of DALYs attributable to modifiable risk factors in 2019 accounted for 69·4% (64·2â74·3) of total peripheral artery disease DALYs. The prevalence of peripheral artery disease was highest in countries with high SDI and lowest in countries with low SDI, whereas DALY and mortality rates showed U-shaped curves, with the highest burden in the high and low SDI quintiles.
Interpretation
The total number of people with peripheral artery disease has increased globally from 1990 to 2019. Despite the lower prevalence of peripheral artery disease in males and low-income countries, these groups showed similar DALY rates to females and higher-income countries, highlighting disproportionate burden in these groups. Modifiable risk factors were responsible for around 70% of the global peripheral artery disease burden. Public measures could mitigate the burden of peripheral artery disease by modifying risk factors.
Funding
Bill & Melinda Gates Foundation
Global, regional, and national incidence of six major immune-mediated inflammatory diseases: findings from the global burden of disease study 2019
Background The causes for immune-mediated inflammatory diseases (IMIDs) are diverse and the incidence trends of IMIDs from specific causes are rarely studied. The study aims to investigate the pattern and trend of IMIDs from 1990 to 2019. Methods We collected detailed information on six major causes of IMIDs, including asthma, inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis, psoriasis, and atopic dermatitis, between 1990 and 2019, derived from the Global Burden of Disease study in 2019. The average annual percent change (AAPC) in number of incidents and age standardized incidence rate (ASR) on IMIDs, by sex, age, region, and causes, were calculated to quantify the temporal trends. Findings In 2019, rheumatoid arthritis, atopic dermatitis, asthma, multiple sclerosis, psoriasis, inflammatory bowel disease accounted 1.59%, 36.17%, 54.71%, 0.09%, 6.84%, 0.60% of overall new IMIDs cases, respectively. The ASR of IMIDs showed substantial regional and global variation with the highest in High SDI region, High-income North America, and United States of America. Throughout human lifespan, the age distribution of incident cases from six IMIDs was quite different. Globally, incident cases of IMIDs increased with an AAPC of 0.68 and the ASR decreased with an AAPC of â0.34 from 1990 to 2019. The incident cases increased across six IMIDs, the ASR of rheumatoid arthritis increased (0.21, 95% CI 0.18, 0.25), while the ASR of asthma (AAPC = â0.41), inflammatory bowel disease (AAPC = â0.72), multiple sclerosis (AAPC = â0.26), psoriasis (AAPC = â0.77), and atopic dermatitis (AAPC = â0.15) decreased. The ASR of overall and six individual IMID increased with SDI at regional and global level. Countries with higher ASR in 1990 experienced a more rapid decrease in ASR. Interpretation The incidence patterns of IMIDs varied considerably across the world. Innovative prevention and integrative management strategy are urgently needed to mitigate the increasing ASR of rheumatoid arthritis and upsurging new cases of other five IMIDs, respectively. Funding The Global Burden of Disease Study is funded by the Bill and Melinda Gates Foundation. The project funded by Scientific Research Fund of Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital (2022QN38)
Prospective comparative assessment of ultrasonography and laparoscopy for contralateral patent processus vaginalis in inguinal hernia presented in the first year of life
Background and purpose Contralateral inguinal exploration in children with unilateral inguinal hernia is still a controversial topic. The aim of this study was to present an evidence-based justification for contralateral inguinal exploration in our population after comparing the results of ultrasonography (US) and laparoscopy.Methods Over a period of 3 years, 246 patients (207 boys and 39 girls) with unilateral inguinal hernia who were presented in the first year of life underwent an US using a 10MHz linear transducer. Operative transinguinal contralateral laparoscopic exploration was carried out in all of them. The results were compared prospectively for the sensitivity and specificity of US and laparoscopy.Results Our results showed a predominant left-side incidence in boys (50.7%) and a right-side incidence in girls (69.2%). With respect to prematurity, 24.6% of boys and 30.8% of patients with left-sided hernia were found to be premature. In all, 64.6% of patients were diagnosed in the neonatal period. We considered positive patent processus vaginalis (PPV) on US when types IâIII according to the criteria of Toki and colleagues were reported. Positive PPV was confirmed by US in 30.5% of patients and by laparoscopy in 85.2%. Sonographic assessment of contralateral PPV gave a sensitivity of 91.7% and a specificity of 87.7%. Of the patients, the laparoscopic exploration yielded positive results in 35.8%. The cost of a negative laparoscopy is 50, which on second admission costs 500$.Conclusion As in our community there is a high incidence of consanguinity, preoperative assessment of contralateral hernia should be considered in patients who are presented in the first year of life and in premature infants. In experienced hands US is a highly sensitive tool for the diagnosis of contralateral hernia. Laparoscopic exploration is safe, rapid, and a proven method for diagnosis, even in infants. We recommend laparoscopic exploration for all patients who are presented in the first year of life in order to avoid second admission, which can lower costs significantly. Keywords: hernia, laparoscopy, pediatric surger