Fine structure of the male accessory glands of Triatoma rubrofasciata (De Geer, 1773) (Hemiptera, Triatominae)

Male of Triatoma rubrofasciata has four elongated sac-like reproductive mesodermic accessory glands, lined by an inner single layer of secretory cells, with basal plasma membrane infolds and short apical microvilli, and externally enveloped by a thin visceral muscle layer. The secretory cells have a well-developed rough endoplasmic reticulum, Golgi complex, mitochondria, and secretory granules. In one day old adult the gland cells are poorly developed, presenting small, electron-transparent secretory granules scattered among the rough endoplasmatic reticulum, whereas in three days old adult these cells have the cisternae of the rough endoplasmatic reticulum varing size degree, filled with granular electrondense content. In five days old males the secretory granules increase in diameter, being released to the gland lumen. Therefore, there is an increase of the secretory activity according to male maturation.     

Biochemical and Biophysical Characterization of the Caveolin-2 Interaction with Membranes and Analysis of the Protein Structural Alteration by the Presence of Cholesterol

Caveolin-2 is a protein suitable for the study of interactions of caveolins with other proteins and lipids present in caveolar lipid rafts. Caveolin-2 has a lower tendency to associate with high molecular weight oligomers than caveolin-1, facilitating the study of its structural modulation upon association with other proteins or lipids. In this paper, we have successfully expressed and purified recombinant human caveolin-2 using E. coli. The structural changes of caveolin-2 upon interaction with a lipid bilayer of liposomes were characterized using bioinformatic prediction models, circular dichroism, differential scanning calorimetry, and fluorescence techniques. Our data support that caveolin-2 binds and alters cholesterol-rich domains in the membranes through a CARC domain, a type of cholesterol-interacting domain in its sequence. The far UV-CD spectra support that the purified protein keeps its folding properties but undergoes a change in its secondary structure in the presence of lipids that correlates with the acquisition of a more stable conformation, as shown by differential scanning calorimetry experiments. Fluorescence experiments using egg yolk lecithin large unilamellar vesicles loaded with 1,6-diphenylhexatriene confirmed that caveolin-2 adsorbs to the membrane but only penetrates the core of the phospholipid bilayer if vesicles are supplemented with 30% of cholesterol. Our study sheds light on the caveolin-2 interaction with lipids. In addition, we propose that purified recombinant caveolin-2 can provide a new tool to study protein–lipid interactions within caveolae.     

Cellular Regulation of Kynurenic Acid-Induced Cell Apoptosis Pathways in AGS Cells

Kynurenic acid was included in the three compounds (caffeic acid, chlorogenic acid, and kynurenic acid) that showed high antioxidant and anti-inflammatory potential among the phenolic compounds contained in Gynura procumbens. In this study, the mechanism of cancer cell death induced by kynurenic acid (KYNA), which has the highest molecular binding affinity, in the gastric cancer cell line AGS was confirmed in molecular docking analysis. KYNA showed the most cancer cell death effect on AGS cells among several gastric cancer cell lines (MKN, AGS, and SNU). AGS cells were used for later experiments, and KYNA concentrations of 0, 150, 200, and 250 µM were used. KYNA inhibited cell migration and proliferation in AGS cells in a concentration-dependent manner. G2/M phase cell cycle arrest and reduction of related proteins (Cdc25C, CDK1 and CyclinB1) were confirmed in KYNA-treated AGS cells. Apoptosis of KYNA-treated AGS cells was confirmed by Annexin V/propidium iodide (PI) staining flow cytometry analysis. As a result of morphological chromatin condensation through DAPI (4′,6-diamidino-2-phenylindole), intense blue fluorescence was confirmed. The mechanism of apoptosis induction of KYNA-treated AGS cells was confirmed by western blotting. In the extrinsic pathway, apoptosis induction markers FasL, Fas, and Caspase-3 and -8 were increased in a concentration-dependent manner upon KYNA treatment. In the intrinsic pathway, the expression of anti-apoptotic factors PI3K, AKT, and Bcl-xL was down-regulated, and the expression of apoptosis-inducing factors BAD, Bak, Bax, Cytochrom C, and Caspase-9 was up-regulated. Therefore, in the present study, we strongly imply that KYNA induces apoptosis in AGS gastric cancer cells. This suggests that KYNA, a natural compound, could be the basis for drug for the treatment of gastric cancer.     

Rapid and Sensitive Immunochromatographic Strip for On‐site Detection of Sulfamethazine in Meats and Eggs

A rapid immunochromatographic (ICG) strip based on a conjugate of colloidal gold and monoclonal antibody (mAb) was developed for the rapid, sensitive, and on‐site detection of sulfamethazine in meat and egg samples. The detection limit of the ICG strip is 2 ng/mL, and the assay can be completed in 10 min. A cross‐reactivity test indicated that the ICG strip was highly specific to sulfamethazine with no cross‐reaction with sulfonamide compounds and other antibiotics. The results of the recovery test from meat and egg samples spiked with sulfamethazine were in good agreement with those obtained by the indirect competitive enzyme‐linked immunosorbent assay. These results demonstrated that the ICG strip can be used as a rapid and qualitative tool for on‐site screening of sulfamethazine in meat and egg samples.     

Effect of cooking on total vitamin C contents and antioxidant activity of sweet chestnuts (Castanea sativa Mill.)

In this work the total vitamin C contents (ascorbic acid + dehydroascorbic acid) and antioxidant activity of raw and cooked chestnuts was evaluated. The vitamin C contents of raw chestnuts varied significantly between the different cultivars (cv) studied and it varied from 400 mg/kg dry weight (cv Lada) to 693 mg/kg dry weight (cv Martaínha). The different cultivars behave differently during the cooking process concerning the loss of vitamin C. A significant decrease in the vitamin C content of the chestnuts was observed, 25–54% for the boiling process and 2–77% for the roasting process. Boiled and roasted chestnuts can be good sources of vitamin C since it may represent 22.4%, 16.2%, 26.8% and 19.4%, respectively, of the recommended dietary intake for an adult man and woman. The cooking process significantly changed the antioxidant activity of the chestnuts. A difference was observed between the cultivars during the cooking processes, concerning the antioxidant activity. For the raw chestnuts the variation in vitamin C content of the chestnuts explains 99% of the antioxidant activity variation but for the roasted and boiled chestnuts this percentage significantly decreases to 51% and 88%, respectively. Although a high antioxidant activity is still present in the cooked chestnuts, the cause for this antioxidant activity is less dependent on the vitamin C content of the chestnuts, probably due to the conversion of ascorbic acid to dehydroascorbic acid. The increase in gallic acid during the cooking process, presumably transferred from the peels to the fruit, also contributes to the high antioxidant activity observed for the cooked chestnuts.     

A Smart Wellness Service Platform and Its Practical Implementation

Advances in the field of medical sciences and medical technology, and present-day challenges, such as an aging population, rising medical expenses, and lifestyle-related diseases, have collectively catalyzed a research ecosystem termed “smart wellness.” This article describes the establishment of a smart wellness service platform designed to empower individuals to create a sense of balance in their lives. Step-by-step details include service model, design, and architectural considerations. As a proof of concept, implementation details of a Health Improvement and Management Systems (HIMS) Hub, a Smart Wellness Service Platform deployed in six cities in South Korea, are presented. An on-site survey conducted in Busan Metropolitan City reveals the percentage of satisfied users to be 91.3%. Furthermore, data gathered from 27,236 physical evaluations of users from a Busan city center over the period of April 2013 to May 2018 reveal that males and females in their 50s and 60s account for the highest number of participants, while males in their 70s have a higher rate of participation than females in the same age group.     

Some Aspects of EEG Frequency Analysis

The purpose of this article is to give a short mathematical introduction to the analysis of EEG signals by means of frequency-selective filters. Besides the resonant frequency, three characteristics of practical filters turn out to be of primary importance. These characteristics are: 1) the time selectivity (width of the window function), indicating the duration of the part of the signal under investigation; 2) the frequency selectivity as bandwidth of the filter; 3) the efficiency, i.e., the ratio of the standard deviation of the filter output to the mean output, in case random noise is fed into the filter.     

Evaluation of in-air hand gestures interaction for older people

Universal Access in the Information Society - In-air gestural interfaces are gaining popularity due to the increasing availability and low cost of gesture recognition hardware. However, the current...     

Star-shaped hexaaryltriindoles small molecules: Tuning molecular properties towards solution processed organic light emitting devices

We present a series of differently substituted star-shaped hexaaryltriindoles with tunable light-emitting properties. The deep blue emission is unchanged by donor peripheral substituents while an increasing acceptor character produces a reduction of the optical gap, an increased Stokes shift and eventually leads to the appearance of a new electronic level and to the simultaneous deep blue (413 nm) and green (552 nm) emission in solution. Quenching by concentration increases with the acceptor character but is lower as the tendency of these compounds to aggregate is stronger. Solution processed thin films present optical and morphological qualities adequate for device fabrication and similar electronic structure compared to solutions with an emission range from 423 nm up to 657 nm (red), demonstrating the possibility of tuning the energy levels by chemical functionalization. We have fabricated and characterized single-layer solution processed organic light emitting diodes (OLED) to investigate the influence on transport and emission properties of the substituting species. We analyzed the I–V response using a single-carrier numerical model that includes injection barriers and non-uniform electric-field across the layer. As a result, we obtained the electric field dependence of the mobility for each device. Best results are obtained on the most electron rich derivative functionalized with six donor methoxy groups. This material shows the highest emission efficiency in solid state, due to aggregation-induced enhancement, and better transport properties with the highest mobility and a very low turn-on voltage of 2.8 V. The solution processed OLED devices produce stable deep blue (CIE coordinates (0.16, 0.16)) to white (CIE coordinates (0.33, 0.3)) emission with similar luminous efficiencies.