333 research outputs found
Insights from SONATA: Implementing and integrating a microservice-based NFV service platform with a DevOps methodology
Prevalence of childhood obesity in schools of Northern Greece
Prevalence of obesity in 592 Greek pupils (7-15 years old) was investigated. Body Mass Index (BMI) was calculated and percentages of overweight and obese children in age groups were assessed. High percentage of Greek children is overweight and obese. Comparison of BMI between schools of Thessaloniki center and the suburbs and between boys and girls showed no statistically significant difference
Performance evaluation of H264/SVC streaming system featuring real-time in-network adaptation
n/
PNAS plus: plasmodium falciparum responds to amino acid starvation by entering into a hibernatory state
The human malaria parasite Plasmodium falciparum is auxotrophic for most amino acids. Its amino acid needs are met largely through the degradation of host erythrocyte hemoglobin; however the parasite must acquire isoleucine exogenously, because this amino acid is not present in adult human hemoglobin. We report that when isoleucine is withdrawn from the culture medium of intraerythrocytic P. falciparum, the parasite slows its metabolism and progresses through its developmental cycle at a reduced rate. Isoleucine-starved parasites remain viable for 72 h and resume rapid growth upon resupplementation. Protein degradation during starvation is important for maintenance of this hibernatory state. Microarray analysis of starved parasites revealed a 60% decrease in the rate of progression through the normal transcriptional program but no other apparent stress response. Plasmodium parasites do not possess a TOR nutrient-sensing pathway and have only a rudimentary amino acid starvation-sensing eukaryotic initiation factor 2α (eIF2α) stress response. Isoleucine deprivation results in GCN2-mediated phosphorylation of eIF2α, but kinase-knockout clones still are able to hibernate and recover, indicating that this pathway does not directly promote survival during isoleucine starvation. We conclude that P. falciparum, in the absence of canonical eukaryotic nutrient stress-response pathways, can cope with an inconsistent bloodstream amino acid supply by hibernating and waiting for more nutrient to be provided
Induction of lymphoidlike stroma and immune escape by tumors that express the chemokine CCL21
Tumor manipulation of host immunity is important for tumor survival and invasion. Many cancers secrete CCL21, a chemoattractant for various leukocytes and lymphoid tissue inducer cells, which drive lymphoid neogenesis. CCL21 expression by melanoma tumors in mice was associated with an immunotolerant microenvironment, which included the induction of lymphoid-like reticular stromal networks, an altered cytokine milieu, and the recruitment of regulatory leukocyte populations. In contrast, CCL21-deficient tumors induced antigen-specific immunity. CCL21-mediated immune tolerance was dependent on host rather than tumor expression of the CCL21 receptor, CCR7, and could protect distant, coimplanted CCL21-deficient tumors and even nonsyngeneic allografts from rejection. We suggest that by altering the tumor microenvironment, CCL21-secreting tumors shift the host immune response from immunogenic to tolerogenic, which facilitates tumor progression
A SDN-based WiFi-VLC Coupled System for Optimised Service Provision in 5G Networks
Abstractâ Visible Light Communication (VLC) is a powerful
supplement, which has gained tremendous attention recently and
has become a favorable technology in short-range communication
scenarios for the Fifth Generation (5G) networks. VLC possesses
a number of prominent features to address the highly demanding
5G system requirements for high capacity, high data rate, high
spectral efficiency, high energy efficiency, low battery
consumption, and low latency. However, this prominent
performance is limited by the imperfect reception, since line of
sight channel condition may not always exist in practice. This
paper presents and experimentally validates a SDN-based VLC
system, which is coupled with WiFi access technology in order to
improve the network QoS, reassuring zero packet loss reception
quality when the user is moving between two consecutive VLC
transmitters
Viral Hepatitis and Rapid Diagnostic Test Based Screening for HBsAg in HIV-infected Patients in Rural Tanzania.
\ud
\ud
Co-infection with hepatitis B virus (HBV) is highly prevalent in people living with HIV in Sub-Saharan Africa. Screening for HBV surface antigen (HBsAg) before initiation of combination antiretroviral therapy (cART) is recommended. However, it is not part of diagnostic routines in HIV programs in many resource-limited countries although patients could benefit from optimized antiretroviral therapy covering both infections. Screening could be facilitated by rapid diagnostic tests for HBsAg. Operating experience with these point of care devices in HIV-positive patients in Sub-Saharan Africa is largely lacking. We determined the prevalence of HBV and Hepatitis C virus (HCV) infection as well as the diagnostic accuracy of the rapid test device Determine HBsAg in an HIV cohort in rural Tanzania. Prospectively collected blood samples from adult, HIV-1 positive and antiretroviral treatment-naïve patients in the Kilombero and Ulanga antiretroviral cohort (KIULARCO) in rural Tanzania were analyzed at the point of care with Determine HBsAg, a reference HBsAg EIA and an anti-HCV EIA. Samples of 272 patients were included. Median age was 38 years (interquartile range [IQR] 32-47), 169/272 (63%) subjects were females and median CD4+ count was 250 cells/”L (IQR 97-439). HBsAg was detected in 25/272 (9.2%, 95% confidence interval [CI] 6.2-13.0%) subjects. Of these, 7/25 (28%) were positive for HBeAg. Sensitivity of Determine HBsAg was rated at 96% (95% CI 82.8-99.6%) and specificity at 100% (95% CI, 98.9-100%). Antibodies to HCV (anti-HCV) were found in 10/272 (3.7%, 95% CI 2.0-6.4%) of patients. This study reports a high prevalence of HBV in HIV-positive patients in a rural Tanzanian setting. The rapid diagnostic test Determine HBsAg is an accurate assay for screening for HBsAg in HIV-1 infected patients at the point of care and may further help to guide cART in Sub-Saharan Africa
Recommended from our members
Eliminating Preventable HIV-Related Maternal Mortality in Sub-Saharan Africa: What Do We Need to Know?
Introduction: HIV makes a significant contribution to maternal mortality, and women living in sub-Saharan Africa are most affected. International commitments to eliminate preventable maternal mortality and reduce HIV-related deaths among pregnant and postpartum women by 50% will not be achieved without a better understanding of the links between HIV and poor maternal health outcomes and improved health services for the care of women living with HIV (WLWH) during pregnancy, childbirth, and postpartum. Methods: This article summarizes priorities for research and evaluation identified through consultation with 30 international researchers and policymakers with experience in maternal health and HIV in sub-Saharan Africa and a review of the published literature. Results: Priorities for improving the evidence about effective interventions to reduce maternal mortality and improve maternal health among WLWH include better quality data about causes of maternal death among WLWH, enhanced and harmonized program monitoring, and research and evaluation that contributes to improving: (1) clinical management of pregnant and postpartum WLWH, including assessment of the impact of expanded antiretroviral therapy on maternal mortality and morbidity, (2) integrated service delivery models, and (3) interventions to create an enabling social environment for women to begin and remain in care. Conclusions: As the global community evaluates progress and prepares for new maternal mortality and HIV targets, addressing the needs of WLWH must be a priority now and after 2015. Research and evaluation on maternal health and HIV can increase collaboration on these 2 global priorities, strengthen political constituencies and communities of practice, and accelerate progress toward achievement of goals in both areas
Accurate microRNA target prediction correlates with protein repression levels
MicroRNAs are small endogenously expressed non-coding RNA molecules that regulate target gene expression through translation repression or messenger RNA degradation. MicroRNA regulation is performed through pairing of the microRNA to sites in the messenger RNA of protein coding genes. Since experimental identification of miRNA target genes poses difficulties, computational microRNA target prediction is one of the key means in deciphering the role of microRNAs in development and diseas
- âŠ