All Data

Microscopic observation is one of the most basic and important skills for experiments in biology classes from compulsory education through to higher education. Microscopic observation in biology can help us better understand the microstructures of organisms and convey notions of beauty and fascination regarding the detailed nature of the microworld, which we cannot observe through our unaided eyes. However, many lab classes were postponed for the summer break because it was difficult for the faculty to conduct lab classes using equipment such as microscopes for non-face-toface learning at the university in the beginning of the COVID-19 pandemic. Under this situation, we planned that students do the experiment at home using handmade microscope. Students could make a simple Leeuwenhoek microscope very easily and use to understand the principle of the microscope. A non-face-to-face class required students to take the initiative in learning, which led to a better understanding of the principles of microscopy. Hence, the future integration of this nonface-to-face learning using a handmade microscope into an existing face-to-face lab class will be very useful for the teaching of science, especially biology, at many schools by science teachers and researchers.

Right ventricular (RV) dysfunction and its linked arrhythmias play a crucial role in determining the prognosis of pulmonary arterial hypertension (PAH). Our paper aimed to explore the potential protective effects of direct pharmacological intervention in the RV muscle using dantrolene (DAN), a stabilizer of the cardiac ryanodine receptor (RyR2), against RV dysfunction and arrhythmia in a rat model of monocrotaline (MCT)-induced PAH. To induce PAH, male 8-week-old Sprague-Dawley rats received MCT injections. The study also assessed the induction of ventricular tachycardia (VT) by catecholamines, examining RyR2-mediated Ca^{2+} release properties in isolated cardiomyocytes. Additionally, a pulmonary artery-banding model was established to evaluate the independent effects of chronic pressure overload on RV morphology and function. In the MCT-induced PAH rat model, findings revealed RV hypertrophy, dilation, and functional decline, resulting in 0% survival rate two months post-MCT induction. Conversely, chronic DAN treatment demonstrated improvements in these RV parameters and an 80% increase in survival. Furthermore, chronic DAN treatment prevented the dissociation of calmodulin from RyR2, inhibiting Ca^{2+} sparks and spontaneous Ca^{2+} transients in MCT-induced hypertrophied RV cardiomyocytes. Epinephrine induced VT in over 50% of rats with MCT-induced PAH, while chronic DAN treatment achieved complete suppression of VT. The paper concludes that stabilizing RyR2 with DAN holds promise as a novel therapeutic approach against the development of RV dysfunction and fatal arrhythmias associated with PAH.