2,188 research outputs found
Thrombospondin-1 protects against Aβ-induced mitochondrial fragmentation and dysfunction in hippocampal cells.
Alzheimer's disease (AD) is often characterized by the impairment of mitochondrial function caused by excessive mitochondrial fragmentation. Thrombospondin-1 (TSP-1), which is primarily secreted from astrocytes in the central nervous system (CNS), has been suggested to play a role in synaptogenesis, spine morphology, and synaptic density of neurons. In this study, we investigate the protective role of TSP-1 in the recovery of mitochondrial morphology and function in amyloid β (Aβ)-treated mouse hippocampal neuroblastoma cells (HT22). We observe that TSP-1 inhibits Aβ-induced mitochondrial fission by maintaining phosphorylated-Drp1 (p-Drp1) levels, which results in reduced Drp1 translocation to the mitochondria. By using gabapentin, a drug that antagonizes the interaction between TSP-1 and its neuronal receptor α2δ1, we observe that α2δ1 acts as one of the target receptors for TSP-1, and blocks the reduction of the p-Drp1 to Drp1 ratio, in the presence of Aβ. Taken together, TSP-1 appears to contribute to maintaining the balance in mitochondrial dynamics and mitochondrial functions, which is crucial for neuronal cell viability. These data suggest that TSP-1 may be a potential therapeutic target for AD
The role of social support and social networks in smoking behavior among middle and older aged people in rural areas of South Korea: A cross-sectional study
<p>Abstract</p> <p>Background</p> <p>Although the number of studies on anti-smoking interventions has increased, studies focused on identifying social contextual factors in rural areas are scarce. The purpose of this study was to explore the role of social support and social networks in smoking behavior among middle and older aged people living in rural areas of South Korea.</p> <p>Methods</p> <p>The study employed a cross-sectional design. Participants included 1,057 adults, with a mean age of 60.7 years, residing in rural areas. Information on participants' tobacco use, stress, social support, and social networks was collected using structured questionnaires. The chi-square test, the t-test, ANOVA, and logistic regression were used for data analysis.</p> <p>Results</p> <p>The overall smoking prevalence in the study was 17.4% (men, 38.8%; women, 5.1%). Overall, stress was high among women, and social support was high among men. Smokers had high levels of social support (t = -2.90, p = .0038) and social networks (t = -2.22, p = .0271), as compared to non- and former smokers. Those in the high social support group were likely to be smokers (AOR = 2.21, 95% CI 1.15-4.26). Women with moderate social ties were less likely to smoke (AOR = 0.18, 95% CI 0.05-0.61).</p> <p>Conclusion</p> <p>There was a protective role of a moderate social network level among women, and a high level of social support was associated with smoking behaviors in rural areas. Findings suggest the need for a comprehensive understanding of the functions and characteristics of social contextual factors including social support and social networks in order to conduct more effective anti-smoking interventions in rural areas.</p
Optimizing Parameters of Information-Theoretic Correlation Measurement for Multi-Channel Time-Series Datasets in Gravitational Wave Detectors
Data analysis in modern science using extensive experimental and
observational facilities, such as a gravitational wave detector, is essential
in the search for novel scientific discoveries. Accordingly, various techniques
and mathematical principles have been designed and developed to date. A
recently proposed approximate correlation method based on the information
theory is widely adopted in science and engineering. Although the maximal
information coefficient (MIC) method remains in the phase of improving its
algorithm, it is particularly beneficial in identifying the correlations of
multiple noise sources in gravitational-wave detectors including non-linear
effects. This study investigates various prospects for determining MIC
parameters to improve the reliability of handling multi-channel time-series
data, reduce high computing costs, and propose a novel method of determining
optimized parameter sets for identifying noise correlations in gravitational
wave data.Comment: 11 pages, 8 figure
Identifying and diagnosing coherent associations and causalities between multi-channels of the gravitational wave detector
The gravitational-wave detector is a very complicated and sensitive
collection of advanced instruments, which is influenced not only by the mutual
interaction between mechanical/electronics systems but also by the surrounding
environment. Thus, it is necessary to categorize and reduce noises from many
channels interconnected by such instruments and environment for achieving the
detection of gravitational waves because it enhances to increase of a
signal-to-noise ratio and reduces false alarms from coincident loud events. For
this reason, it is of great importance to identify some coherent associations
between complicated channels. This study presents a way of identifying (non-)
linear couplings between interconnected channels by using some correlation
coefficients, which are applied to practical issues such as noises by hardware
injection test, lightning strokes, and air compressor vibrations
gravitational-wave detector.Comment: 10 pages, 8 figures, and 2 table
Unusual Primary Peritonitis due to Streptococcus pyogenes in a Young Healthy Woman
We describe the first case of primary peritonitis in Korea of a healthy person due to Streptococcus pyogenes. In the absence of comorbid conditions, such as liver cirrhosis, immunosuppression, or nephrotic syndrome, primary peritonitis is uncommon in a young healthy woman. Abdomen computed tomography revealed ascites in the lower abdomen and peritoneal enhancement suggesting peritonitis. In diagnostic laparoscopy, purulent ascites was found in the pelvic cavity but both ovaries and fallopian tubes were intact. There were no intra-abdominal abnormalities such as bowel perforation, appendicitis, or necrosis. The reports of blood culture, ascites culture, and cervical swab culture confirmed S. pyogenes. After use of antibiotics, the patient was cured and discharged without sequelae
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