A differential role of macrophage TRPM2 channels in Ca²âº signaling and cell death in early responses to H2O2.

Reactive oxygen species such as H2O2 elevates the cytosolic Ca²âº concentration ([Ca²âº]c) and causes cell death via poly(ADPR) polymerase (PARP) activation, which also represents the primary mechanism by which H2O2 activate the transient receptor potential melastatin-related 2 (TRPM2) channel as a Ca²âº-permeable channel present in the plasma membrane or an intracellular Ca²âº-release channel. The present study aimed to define the contribution and mechanisms of the TRPM2 channels in macrophage cells in mediating Ca²âº signaling and cell death during initial response to H2O2, using mouse peritoneal macrophage, RAW264.7, and differentiated THP-1 cells. H2O2 evoked robust increases in the [Ca²âº]c, and such Ca²âº responses were significantly greater at body temperature than room temperature. H2O2-induced Ca²âº responses were strongly inhibited by pretreatment with PJ-34, a PARP inhibitor, and largely prevented by removal of extracellular Ca²âº. Furthermore, H2O2-induced increases in the [Ca²âº]c were completely abolished in macrophage cells isolated from trpm2-/- mice. H2O2 reduced macrophage cell viability in a duration- and concentration-dependent manner. H2O2-induced cell death was significantly attenuated by pretreatment with PJ-34 and TRPM2 channel deficiency but remained significant and persistent. Taken together, these results show that the TRPM2 channel in macrophage cells functions as a cell surface Ca²âº-permeable channel that mediates Ca²âº influx and constitutes the principal Ca²âº signaling mechanism but has a limited, albeit significant, role in cell death during early exposure to H2O2.

Effect of mask coverage on face identification in Taiwanese men and women.

Mask wearing is the easiest and most effective way to avoid COVID-19 infection; however, it affects interpersonal activities, especially face identification. This study examined the effects of three mask coverage levels (full coverage, FC; coverage up to the middle [MB] or bottom of the nose bridge [BB]) on face identification accuracy and time. A total of 115 university students (60 men and 55 women) were recruited to conduct a computer-based simulation test consisting of 30 questions (10 questions [five face images each of men and women] for the three mask coverage levels). One unmasked target face and four face images with a specified mask coverage level were designed for each question, and the participants were requested to select the same face from the four covered face images on the basis of the target face. The ANOVA results indicated that identification accuracy was significantly affected by sex (p < 0.01) and the mask coverage level (p < 0.001), whereas identification time was only influenced by sex (p < 0.05). The multiple comparison results indicated that the identification accuracy rate for faces wearing a mask with FC (90.3%) was significantly lower than for those wearing masks with coverage up to the MB (93.7%) and BB (94.9%) positions; however, no difference in identification accuracy rate was observed between the MB and BB levels. Women exhibited a higher identification accuracy rate than men (94.1% vs. 91.9%) in identifying unfamiliar faces, even though they may spend less time identifying the images. A smaller mask coverage level (i.e., the BB level) does not facilitate face identification. The findings can be served as a reference for people to trade-off between wearing a mask and interpersonal interaction in their daily activities.

Creating a Healthy Life for the Elderly through Participation in Self-Media: A Study on the Demands of the Elderly in Self-Media.

In recent years, with the trends in digital media and a shift in the sources of information, self-media has gradually become a unique new type of media with considerable potential. Numerous related studies have also indicated that participating in self-media positively impacts the elderly, especially in self-media regarding healthcare and welfare. However, research has seldom explored the demands and services for elderly participation in self-media. In this study, the research targets were 55-75 years of age, in good health, with a monthly disposable income of more than TWD 30,000 (N = 180). The research methods had two aims: (1) to analyze the current well-known self-media and websites related to healthcare; and (2) via the Kano Model questionnaire, to survey and explore the demand for self-media among the elderly. The results summarize and describe the preferred layout, content items, interaction methods, and information display of self-media content for the elderly. We anticipate designing a self-media website platform that meets the demands of the elderly and that continues to develop into social media platforms and audio-visual content in the future.

Transneuronal Degeneration of Thalamic Nuclei following Middle Cerebral Artery Occlusion in Rats.

Objective. Postinfarction transneuronal degeneration refers to secondary neuronal death that occurs within a few days to weeks following the disruption of input or output to synapsed neurons sustaining ischemic insults. The thalamus receives its blood supply from the posterior circulation; however, infarctions of the middle cerebral arterial may cause secondary transneuronal degeneration in the thalamus. In this study, we presented the areas of ischemia and associated transneuronal degeneration following MCAo in a rat model. Materials and Methods. Eighteen 12-week-old male Sprague-Dawley rats were randomly assigned to receive middle cerebral artery occlusion surgery for 1, 7, and 14 days. Cerebral atrophy was assessed by 2,3,5-triphenyltetrazolium hydrochloride staining. Postural reflex and open field tests were performed prior to animal sacrifice to assess the effects of occlusion on behavior. Results. Myelin loss was observed at the lesion site following ischemia. Gliosis was also observed in thalamic regions 14 days following occlusion. Differential degrees of increased vascular endothelial growth factor expression were observed at each stage of infarction. Increases in myelin basic protein levels were also observed in the 14-day group. Conclusion. The present rat model of ischemia provides evidence of transneuronal degeneration within the first 14 days of occlusion. The observed changes in protein expression may be associated with self-repair mechanisms in the damaged brain.

Marine phytoplankton motility sensor integrated into a microfluidic chip for high-throughput pollutant toxicity assessment.

A microfluidic chip was designed to assess the toxicity of pollutants in a high-throughput way by using marine phytoplankton motility as a sensor signal. In this chip, multiple gradient generators (CGGs) with diffusible chambers enable large scale of dose-response bioassays to be performed in a simple way. Two mobile marine phytoplankton cells were confined on-chip and stimulated by 8 concentrations (generated by CGG) of Hg, Pb, Cu and phenol singly, as well as Cu and phenol jointly. CASA system was used to characterize motility by motile percentage (%MOT), curvilinear velocity (VCL), average path velocity (VAP) and straight line velocity (VSL). In all cases, dose-dependent inhibitions of motility were observed. In the present system, only 2h was needed to predict EC50. Thus, the developed microfluidic chip device was proved to be useful as a rapid/simple and high-throughput test method in marine pollution toxicity assessment.