Structural, Functional and Molecular Dynamics Examination of a de novo cloned Otopetrin-like Proton Channel in crayfish.

Proton channels play a crucial role in many biological functions, as they are responsible for the selective transport of protons across cell membranes. Recently, Otopetrins, a family of eukaryotic proton-selective ion channels, have attracted significant attention due to their diverse physiological roles. Despite the importance of Otopetrins, their structural and functional properties remain relatively unexplored. As a model organism, crayfish have been extensively studied to gain insights into the functioning of the nervous system. These studies cover a wide range of aspects, including the properties of individual neurons and behavioral science. However, studying the physiological systems of crayfish poses challenges for molecular research due to limited molecular sequence information available for these organisms. In the present work was identified an originally cloned mRNA, coding an Otopetrin like proton channel in the crayfish. The coded protein was modeled in silico and possible conduction mechanisms and pathways were revealed. A plasmid of the cloned mRNA was heterologously expressed in HEK293T cells. Functional experiments on transfected cells indicated that the expressed mRNA was coupled to proton conduction across the cell membrane.

Radiation dose to breasts from a cardiac computed tomography angiographyscanogram can be reduced by switching tube position.

BACKGROUND/AIM: In a computed tomography (CT) examination, scanogram images are used to determine the range of the area to be imaged before scanning. The importance of scanogram image exposure has increased since total examination radiation has decreased due to technological advancements. The purpose of this study was to determine and compare radiation doses delivered to patients while the tube was in anterior-posterior (AP) and posterior-anterior (PA) positions during a CT angiography scanogram. MATERIALS AND METHODS: The radiation doses absorbed by the breast tissue of 55 female patients who underwent cardiac dual-source computed tomography (DSCT) angiography were determined using thermoluminescent dosimeters (TLD-100, Harshaw, MA, USA). Four patients were excluded from the study for various reasons. RESULTS: Radiation doses absorbed by the breasts were significantly lower when the tube position was switched during the scanogram. The absorbed doses, calculated from scanogram exposures, were 520 ± 50 µSv for the AP projection and 410 ± 45 µSv for the PA projection. Total skin doses from the DSCT examinations were 18.9 ± 2.3 mSv. CONCLUSION: We attributed the approximately 20% lower doses to the position of the scanogram tube, which was in the PA position.

Once the Light Touch to the Brain: Cytotoxic Effects of Low-Dose Gamma-Ray, Laser Light, and Visible Light on Rat Neuronal Cell Culture.

OBJECTIVE: We aimed to evaluate the effects of gamma-ray, laser light, and visible light, which neurons are commonly exposed to during treatment of various cranial diseases, on the viability of neurons. MATERIALS AND METHODS: Neuronal cell culture was prepared from the frontal cortex of 9 newborn rats. Cultured cells were irradiated with gamma-ray for 1-10 min by (152)Eu, (241)Am, and (132)Ba isotopes, visible light for 1-160 min, and laser light for 0.2-2 seconds. The MTT tetrazolium reduction assay was used to assess the number of viable cells in the neuronal cell cultures. Wavelength dispersive X-ray fluorescence spectrometer was used to determine Na, K, and Ca levels in cellular fluid obtained from neuronal cell culture plaques. RESULTS: Under low-dose radiation with (152)Eu, (241)Am, and (132)Ba isotopes, cell viability insignificantly decreased with time (p>0.05). On the other hand, exposure to visible light produced statistically significant decrease in cell viability at both short- (1-10 min) and long-term (20-160 min). Cell viability did not change with 2 seconds of laser exposure. Na, K, and Ca levels significantly decreased with gamma-ray and visible light. The level of oxidative stress markers significantly changed with gamma-ray. CONCLUSION: In conclusion, while low dose gamma-ray has slight to moderate apoptotic effect in neuronal cell cultures by oxidative stress, long-term visible light induces remarkable apoptosis and cell death. Laser light has no significant effect on neurons. Further genetic studies are needed to clarify the chronic effect of visible light on neuronal development and functions.