An Updated Search of Steady TeV γ−\gamma-Ray Point Sources in Northern Hemisphere Using the Tibet Air Shower Array

Using the data taken from Tibet II High Density (HD) Array (1997 February-1999 September) and Tibet-III array (1999 November-2005 November), our previous northern sky survey for TeV $\gamma-$ray point sources has now been updated by a factor of 2.8 improved statistics. From $0.0^{\circ}$ to $60.0^{\circ}$ in declination (Dec) range, no new TeV $\gamma-$ray point sources with sufficiently high significance were identified while the well-known Crab Nebula and Mrk421 remain to be the brightest TeV $\gamma-$ray sources within the field of view of the Tibet air shower array. Based on the currently available data and at the 90% confidence level (C.L.), the flux upper limits for different power law index assumption are re-derived, which are approximately improved by 1.7 times as compared with our previous reported limits.Comment: This paper has been accepted by hepn

The Correlations of Plasma and Cerebrospinal Fluid Amyloid-Beta Levels with Platelet Count in Patients with Alzheimer’s Disease

Purpose. Recent study shows that blood-derived amyloid-beta (Aβ) can induce cerebral amyloidosis and is involved in the pathogenesis of Alzheimer’s disease (AD). The vast majority of blood Aβ is generated from platelet. Whether blood Aβ levels are associated with the count of platelets remains unknown. Methods. 58 clinically diagnosed AD patients, 18 11C-PIB-PET diagnosed AD patients, and 61 age- and gender-matched cognitively normal controls were included to analyze the correlation of plasma Aβ levels with platelet count. 13 AD patients and 40 controls with cerebrospinal fluid (CSF) samples were included to further analyze the correlation of CSF Aβ levels with platelet count. Aβ40 and Aβ42 levels in plasma and CSF were measured by ELISA kits. Results. The plasma Aβ42 level was positively correlated with platelet count in both AD patients and control group, especially in AD patients with positive PIB-PET, while there was no correlation as to Aβ40. The CSF Aβ levels also had no significant correlation with platelet count. Conclusion. It suggests that platelets may be involved in the pathogenesis of AD and become a potential peripheral biomarker for AD

The Correlations of Plasma and Cerebrospinal Fluid Amyloid-Beta Levels with Platelet Count in Patients with Alzheimer’s Disease

Purpose. Recent study shows that blood-derived amyloid-beta (Aβ) can induce cerebral amyloidosis and is involved in the pathogenesis of Alzheimer’s disease (AD). The vast majority of blood Aβ is generated from platelet. Whether blood Aβ levels are associated with the count of platelets remains unknown. Methods. 58 clinically diagnosed AD patients, 18 11C-PIB-PET diagnosed AD patients, and 61 age- and gender-matched cognitively normal controls were included to analyze the correlation of plasma Aβ levels with platelet count. 13 AD patients and 40 controls with cerebrospinal fluid (CSF) samples were included to further analyze the correlation of CSF Aβ levels with platelet count. Aβ40 and Aβ42 levels in plasma and CSF were measured by ELISA kits. Results. The plasma Aβ42 level was positively correlated with platelet count in both AD patients and control group, especially in AD patients with positive PIB-PET, while there was no correlation as to Aβ40. The CSF Aβ levels also had no significant correlation with platelet count. Conclusion. It suggests that platelets may be involved in the pathogenesis of AD and become a potential peripheral biomarker for AD

Investigation of pathogenetic mechanism, prevention and treatment of Alzheimer's disease via systemic approaches

Alzheimer's disease (AD) becomes a major disease affecting the elderly with high prevalence. However, no disease-modifying therapies are currently available. AD has long been regarded as a disease of brain itself, but recent studies found that systemic disorders are associated with risk for AD. During the period of Twelfth Five-Year Plan for National Economic and Social Development, our team tried to reveal the pathogenesis, targets, amyloid β-protein (Aβ) clearence pathway and drugs from both central and peripheral approaches, and have discovered: 1) the ratio of p75 neurotrophin receptor (p75NTR) in the brain of AD regulates the over?production and clearence of Aβ in sporadic AD. 2) Peripheral Aβ is able to enter brain, forms AD-type pathologies and induces neuronal deficits, revealing the peripheral mechanism of AD. 3) The effectiveness and safety of brain A β clearance by peripheral organs and tissues has been verified. Based on these findings, we proposed a systemic view of AD, to understand pathogenesis and develop novel diagnostic methods and therapies from a systemic approach. DOI: 10.3969/j.issn.1672-6731.2018.01.00