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There are now various theories on the pathophysiology of Alzheimer's disease (AD), the β-Amyloid (Aβ) cascade hypothesis has garnered a lot of interest. This text applied lentivirus-encapsulated plasmid to transfect APP695 (K595N, M596L) gene into SH-SY5Y cells and thereby obtain a stable cell line over-expressing Aβ. We used qPCR to monitor the mRNA expression of β-Amyloid Precursor Protein (APP) gene, β-Site APP Cleaving Enzyme 1 (BACE1) gene, we also used Western Blot to detect the APP protein, BACE1 protein, and Aβ1-42, respectively, in addition, the expression of Aβ1-42 in SH-SY5Y cell lysate and cell culture supernatant was measured by Enzyme-Linked Immunosorbent Assay (ELISA). The findings demonstrated APP gene over-expression following APP695 (K595N, M596L) gene transfection, and also indicated the successful establishment of the Swedish mutant cell model. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) is considered as one of the major life-threatening health issues worldwide. Growing number of cases every year is demanding rapid, portable, and early detection by the sensing devices for the identification of MI. This research work introduces a modified interdigitated electrode (IDE) sensing surface constructed with single-walled carbon nanotube (SWCN) to detect the cardiac biomarker, C-reactive protein (CRP). CRP-specific aptamer was conjugated with gold nanoparticle and attached on SWCN-constructed IDE surface. This probe-modified sensing surface has reached the limit of CRP detection to 10 pM on a linear regression curve with the regression coefficient of R² = 0.9223 [y = 0.9198x - 0.4326]. Further, control molecules, such as random aptamer sequence and nontarget cardiac biomarker (Troponin I), did not show the current response, indicating the specific CRP detection. This sensing strategy helps to detect the lower level of CRP and diagnose the MI at its earlier stages. [ABSTRACT FROM AUTHOR]

Differential phase-contrast (DPC) X-ray imaging has been performed in the Talbot–Lau configuration, in which the X-ray source was a combination of an absorption grating and a laboratory X-ray generator. We report here quantitative analysis of partial coherence effects on the X-ray Talbot–Lau interferometer. Based on the visibility of the self-image, the well-known geometry condition is reproduced. It is shown that effects of partial coherence are determined by the opening ratio of the source grating, and that the effects are independent of the Talbot order and the type of the phase grating, a condition quite different from those in a Talbot interferometer. A possible explanation is discussed from the point of view of the effective spatial coherence length. Taking into account the available X-ray flux and experimental fluctuations, we present the optimum opening ratio. Furthermore, we mention that our results can also be successfully used to discuss the properties of a multiline X-ray source. [ABSTRACT FROM AUTHOR]

The influence of polychromaticity of the X-ray source on the performance of an X-ray Talbot interferometer applied for phase-contrast imaging is analyzed through numerical simulations based on the Fresnel diffraction theory. The presented simulation results show that the visibility of the self-image is fairly insensitive to the source polychromaticity and explain why the interferometer could be well combined with polychromatic X-ray sources in recent experiments. Furthermore, the self-image with a high visibility can be obtained under polychromatic illumination even at a high-order fractional Talbot distance. This fact implies that the acquired image quality for phase measurements can be improved, since the primary signal for phase measurement is proportional to the inter-grating distance. Finally, we mention that the results are also valid for Talbot–Lau interferometer and scanning double-grating configuration. [ABSTRACT FROM AUTHOR]