High-Sensitivity 3D ZIF-8/PDA Photonic Crystal-Based Biosensor for Blood Component Recognition.

Optical biosensors are sensitive devices used in bioanalytics detection. Analysis of blood constituents is very important for the detection of major diseases and also performs a significant role in the diagnosis of diabetes, various cancers, and cardiovascular disorders. In this work, a three-dimensional photonic crystal-based biosensor composed of zeolitic imidazolate framework-8 (ZIF-8) nanoarrays are placed on polydopamine (PDA) coated on a silicon substrate. This sensor is designed, simulated, and evaluated for various blood components in the wavelength range of 1.1 to 1.5 µm by the finite-difference time-domain (FDTD) method. The proposed biosensor was used for 10 types of blood components such as biotin-streptavidin, bovine serum albumin (BSA), cytop, glucose (40 mg/100 mL), hemoglobin, blood plasma, Sylgard184, white blood compounds, urethane dimethacrylate, and polyacrylamide. The FDTD technique was used for the performance analysis of the biosensor. The design parameters of the radius, the lattice constant, the thickness of the ZIF-8 arrays, and the PDA layer thickness are chosen to optimize the photonic crystal structure. This study indicates that the thickness of the PDA is the most important parameter for peak wavelength value in comparison to the other physical parameters. The factors for optimizing the photonic crystal-based biosensors such as the peak wavelength value (PWV), sensitivity, full width at half-maximum (FWHM), and figure of merit (FOM) are significant in comparison with pertinent works in this field, which evaluated 171 nm/RIU, 7.62 nm, and 22.5 RIU-1, respectively. A change of 0.01 nm in the refractive index of the constituents of the blood leads to a shift of 80 nm in the maximum peak wavelength, therefore acting as a functional biosensor with a high detection limit of 0.004 RIU.

Antidepressant-like and memory-enhancing effects of the N-type calcium channel blocker ziconotide in rats.

The lack of oral or injectable formulations of ziconotide (ω-conotoxin peptide), a novel analgesic agent, limits research on potential neurobehavioral protective properties of this substance, including antidepressant-like effects. Here we expose rats to a stress paradigm that induces depression and memory impairment to assess the effects of ziconotide treatment. Ziconotide was administered intracerebroventricular (i.c.v.) to rats undergoing stereotaxic surgery at a single dose (1 µg/rat) or in repeated long-term applications (dosage groups: 0.1, 0.3, and 1 µg/rat). The antidepressant activity and memory-enhancing effects of ziconotide were examined via the forced swimming test, the Morris water maze test, and the passive avoidance learning test. Behavioral results showed that long-term i.c.v. ziconotide administration significantly decreased the immobility time and delayed the latency period to immobility in a dose-dependent manner compared to controls. In the passive avoidance learning test, the latency period increased, and in the Morris water maze test, the platform location latency time decreased. A single dose of ziconotide (1 µg/rat) did not show a significant effect on memory function or depression parameters during the same tests. Animals were sacrificed immediately after behavioral testing, and both hippocampi were removed and prepared for BDNF evaluation. Hippocampal BDNF levels were significantly increased in rats receiving long-term i.c.v. ziconotide compared to controls. Our results suggest that long-term consumption of ziconotide may attenuate the severity of depression-like behavior and could be useful for preventing memory impairments in various learning models by elevating BDNF levels.

Overexpression of receptor for advanced glycation end products (RAGE) in ovarian cancer.

BACKGROUND: Ovarian cancer is one of the important challenges in the field of gynecologic oncology because of some problems in understanding its etiology and pathogenesis. Receptor for advanced glycation end products (RAGE) is a multiligand trans-membranous receptor which is upregulated in some human cancers. Mechanisms of RAGE involvement in carcinogenesis of ovarian cancer are unknown. OBJECTIVE: This study aimed to investigate the expression of RAGE in ovarian cancers and its association with clinicopathological characteristics. METHODS: The RAGE expression level in ovarian cancer and corresponding noncancerous tissues were analyzed by real time quantitative RT-PCR and immunohistochemistry techniques. RESULTS: Results indicated that RAGE gene was overexpressed in ovarian cancer tissue compared with adjacent noncancerous tissue (p < 0.001). A significant association between RAGE expression and tumor size (p = 0.04), depth of stromal invasion (p = 0.031), lymphovascular invasion (p = 0.041) and stage of cancer (p = 0.041) was observed. The receiver operating characteristic (ROC) analyses yielded the area under the curve (AUC) values of 0.86 for RAGE in discriminating ovarian cancer samples from non-cancer controls. CONCLUSIONS: In conclusion overexpression of RAGE in ovarian cancer may be a useful biomarker to predict tumor progression.

Increased Expression of the Receptor for Advanced Glycation End-Products (RAGE) Is Associated with Advanced Breast Cancer Stage.

BACKGROUND: The receptor for advanced glycation end-products (RAGE) is a multiligand transmembrane receptor that is overexpressed in various pathological conditions including cancers. However, the expression pattern of RAGE in breast cancer tumors is still not completely clear. METHODS: In this study, we investigated the expression levels of RAGE in 25 fresh-frozen breast cancer samples and corresponding noncancerous tissue samples collected from breast cancer patients, by real-time polymerase chain reaction (PCR). Additionally, we performed immunohistochemistry on breast cancer specimens. RESULTS: The results indicate a high expression of the RAGE-encoding gene in the cancerous tissues. RAGE expression at the mRNA and protein levels was statistically significantly up-regulated in advanced-stage and triple-negative breast tumors and node-positive tissues compared with other tissues (p < 0.001). A significant association between RAGE expression and tumor size was observed (p = 0.029). CONCLUSIONS: Overexpression of RAGE in advanced-stage tumors may be a useful biomarker for diagnosis and the prediction of breast cancer progression.