CSF biomarkers of immune activation and Alzheimer\u27s disease for predicting cognitive impairment risk in the elderly

The immune system substantially influences age-related cognitive decline and Alzheimer\u27s disease (AD) progression, affected by genetic and environmental factors. In a Mayo Clinic Study of Aging cohort, we examined how risk factors like APOE genotype, age, and sex affect inflammatory molecules and AD biomarkers in cerebrospinal fluid (CSF). Among cognitively unimpaired individuals over 65

Graph-Theoretic Based Connectivity Restoration Algorithms for Mobile Sensor Networks

In mobile sensor networks (MSN), actuated sensors collaborate with each other in some predefined missions. The collaboration requires application-level coordination based on a strongly connected underlying network, which is often in an infrastructure-free ad hoc manner. The particular network topology provides flexibility as well as vulnerability to the potential applications of MSN; for example, the connectivity can be easily jeopardized if the network is partitioned into disjoint segments from the failure of some critical sensors. In this paper, a critical sensor determination and substitution (CSDS) strategy is proposed to address the important problem of network partitions in mobile sensor networks (MSN) due to the failure of particular sensors. CSDS utilizes a graph-theoretic method to locally identify critical sensors with 2-hop neighboring information. Then, an efficient backup sensor selection algorithm is proposed to monitor the critical sensors and, if necessary, substitute it in order to eliminate the partitions in MSN. The main contribution of our proposed work is that CSDS requires the relocation of only one sensor in each partition elimination process, so that the impacts on the primary missions of the MSN are minimized. Experimental simulations are conducted to evaluate the correctness and effectiveness of CSDS

Decreased myeloid dendritic cells indicate a poor prognosis in patients with severe fever with thrombocytopenia syndrome

Objectives: Severe fever with thrombocytopenia syndrome (SFTS) is a newly emerging infectious disease caused by a novel bunyavirus in which host immune system suppression is thought to be crucial in the development of disease. This study was designed to study the frequencies and activation status of dendritic cells (DCs) at different stages of SFTS and their association with disease severity. Methods: All confirmed SFTS patients (N = 115) were recruited from the Wuhan Union Hospital in 2015; routine laboratory parameters were collected. The frequencies, phenotypes, and subsets of circulating DCs, including myeloid and plasmacytoid dendritic cells (mDCs and pDCs), were analyzed by flow cytometry. Serum levels of interleukin (IL)-6, IL-10, and tumor necrosis factor alpha (TNF-α) were detected by ELISA. The laboratory parameters and other clinical events related to mortality were assessed by multivariate logistic regression analysis and receiver operating characteristic (ROC) curves. Results: The frequency of circulating mDCs, especially from day 9 after disease onset, could serve as a valuable prognostic biomarker for the outcome in SFTS patients (area under the curve = 0.929, p < 0.0001). In addition, persistent down-regulation of the co-stimulatory molecules CD80/CD86 on the mDCs was observed during the disease process. Moreover, levels of mDCs were inversely correlated with the production of IL-6, IL-10, and TNF-α and with viral load at admission. Conclusions: The present results indicate that DCs might be functionally impaired in SFTS. A decreased level of circulating mDCs was closely correlated with the severity of SFTS

Severe anemia is associated with increased short-term and long-term mortality in patients hospitalized with cirrhosis

Introduction and Objectives: The relationship between anemia and the outcome of patients with cirrhosis is not completely clear. Therefore, we performed this large-scale epidemiological study to investigate the prevalence and severity of anemia in patients with cirrhosis and acute decompensation or liver injury and how anemia impacts short-term and long-term outcomes. Patients and Methods: Patients with cirrhosis and acute decompensation (AD) or acute liver injury (ALI) were enrolled in the Chinese AcuTe on CHronic LIver FailurE (CATCH-LIFE) studies, which consisted of two large, multicenter, prospective, observational cohorts between January 2015 and December 2016 and July 2018 and January 2019. We conducted data analysis on the prevalence of anemia and determined the relationship between anemia and prognosis. Results: Among 1979 patients, 1389 (70.2%) had anemia, among whom 599 (41.3%) had mild anemia, 595 (15.8%) had moderate anemia and 195 (2.4%) had severe anemia. A linear association between hemoglobin level and 90-day or 1-year LT-free mortality was shown, and a 10 g/L decrease in hemoglobin level was associated with a 6.8% extra risk of 90-day death and a 5.7% extra risk of 1-year death. Severe anemia was an independent risk factor for 90-day [HR=1.649 (1.100, 2.473), p=0.016] and 1-year LT-free mortality [HR=1.610 (1.159, 2.238), p=0.005]. Multinomial logistic regression analysis further identified that severe anemia was significantly associated with post-28-day mortality but not within-28-day mortality. Conclusions: Anemia is common in patients with cirrhosis admitted for acute events. Severe anemia was associated with poor 90-day and 1-year prognoses in these patients

Analysis of the long-term impact on cellular immunity in COVID-19-recovered individuals reveals a profound nkt cell impairment

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) affected over 120 million people and killed over 2.7 million individuals by March 2021. While acute and intermediate interactions between SARS-CoV-2 and the immune system have been studied extensively, long-term impacts on the cellular immune system remain to be analyzed. Here, we comprehensively characterized immunological changes in peripheral blood mononuclear cells in 49 COVID-19-convalescent individuals (CI) in comparison to 27 matched SARS-CoV-2-unexposed individuals (UI). Despite recovery from the disease for more than 2 months, CI showed significant decreases in frequencies of invariant NKT and NKT-like cells compared to UI. Concomitant with the decrease in NKT-like cells, an increase in the percentage of annexin V and 7-aminoactinomycin D (7-AAD) double-positive NKT-like cells was detected, suggesting that the reduction in NKT-like cells results from cell death months after recovery. Significant increases in regulatory T cell frequencies and TIM-3 expression on CD4 and CD8 T cells were also observed in CI, while the cytotoxic potential of T cells and NKT-like cells, defined by granzyme B (GzmB) expression, was significantly diminished. However, both CD4 and CD8 T cells of CI showed increased Ki67 expression and were fully able to proliferate and produce effector cytokines upon T cell receptor (TCR) stimulation. Collectively, we provide a comprehensive characterization of immune signatures in patients recovering from SARS-CoV-2 infection, suggesting that the cellular immune system of COVID-19 patients is still under a sustained influence even months after the recovery from disease. IMPORTANCE Wuhan was the very first city hit by SARS-CoV-2. Accordingly, the patients who experienced the longest phase of convalescence following COVID-19 reside here. This enabled us to investigate the “immunological scar” left by SARS-CoV-2 on cellular immunity after recovery from the disease. In this study, we characterized the long-term impact of SARS-CoV-2 infection on the immune system and provide a comprehensive picture of cellular immunity of a convalescent COVID-19 patient cohort with the longest recovery time. We revealed that the cellular immune system of COVID-19 patients is still under a sustained influence even months after the recovery from disease; in particular, a profound NKT cell impairment was found in the convalescent phase of COVID-19

Near-Earth Magnetic Field Effects of Large-Scale Magnetospheric Currents

Magnetospheric currents play an important role in the electrodynamics of near- Earth space. This has been the topic of many space science studies. Here we focus on the magnetic fields they cause close to Earth. Their contribution to the geomagnetic field is the second largest after the core field. Significant progress in interpreting the magnetic fields from the different sources has been achieved thanks to magnetic satellite missions like rsted, CHAMP and now Swarm. Of particular interest for this article is a proper representation of the magnetospheric ring current effect. Uncertainties in modelling its effect still produce the largest residuals between observations and present-day geomagnetic field models. A lot of progress has been achieved so far, but there are still open issues like the characteristics of the partial ring current. Other currents discussed are those flowing in the magnetospheric tail. Also their magnetic contribution at LEO orbits is non-negligible. Treating them as an independent source is a more recent development, which has cured some of the problems in geomagnetic field modelling. Unfortunately there is no index available for characterizing the tail current intensity. Here we propose an approach that may help to properly quantify the magnetic contribution from the tail current for geomagnetic field modelling. Some open questions that require further investigation are mentioned at the end