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The major membrane currents responsible for sinoatrial and idioventricular rhythm-generation were studied in isolated rat heart preparations, perfused in Langendorff mode. The rates of whole isolated hearts beating with sinoatrial rhythm decreased with cesium and ivabradine, both blockers of the funny current, and were not affected by nickel, at a dose which blocks T-type calcium current. The sinoatrial rhythm was completely abolished by reduction or removal of sodium from the perfusate (interventions that inhibit calcium-extrusive mode of the sodium/calcium exchanger), or by nifedipine, an L-type calcium channel blocker. Idioventricular rhythm, however, was arrested only by reduction of sodium in the perfusate. Ivabradine reduced the idioventricular rate, nickel did not cause any change, while nifedipine in some cases increased it. The inferences made based on these observations are that INCX and ICaL are obligatory rhythm-generating currents in the sinoatrial node, while INCX is the only obligatory mechanism for an idioventricular rhythm. The funny current is not an obligatory requirement for sinoatrial as well as idioventricular rhythm-generation. However, it enhances the frequency of LCRs. Our results in the isolated whole heart are in corroboration with results from isolated cells.

Patch-clamp electrophysiological recordings of neuronal activity require a large amount of space and equipment. The technique is difficult to master and not conducive to demonstration to more than a few medical students. Therefore, neurophysiological education is mostly limited to classroom-based pedagogies such as lectures. However, the demonstration of concepts such as changes in membrane potential and ion channel activity is best achieved with hands-on approaches. This article details an in silico activity suitable for large groups of medical students that demonstrates the key concepts in neurophysiology using the LabAXON simulation software. Learning activities in our practical include 1) measurements of voltage and time parameters of the neuronal action potential and its relationship to the Nernst potentials of Na+ and K+; 2) determination of the stimulus threshold to evoke action potentials; 3) demonstration of the refractory period of an action potential; and 4) voltage-clamp experiments to determine the current-voltage relationship of voltage-gated Na+ and K+ channels and the voltage dependence of, and recovery from, inactivation of voltage-gated Na+ channels. We emphasized the accuracy of quantitative measurements as well as the correct use of units. The level of difficulty of the activity can be altered through different multiple choice questions relating to material introduced in the associated lectures. This practical activity is suitable for different class sizes and is adaptable for delivery with online platforms. Student feedback showed that the students felt the activity helped them consolidate their understanding of the lecture material.

This sourcebook update describes a variation of a previous sourcebook experiment that used isolated extensor digitorum longus muscle from mouse to teach skeletal muscle properties (Head SI, Arber MS. Adv Physiol Educ 37: 405–414, 2013). Gastrocnemius-sciatic nerve preparation in an anaesthetized rat was developed and muscle contractions were recorded in a computerized data acquisition system using an isometric force transducer. Teachers and students in physiology or biology can use this preparation to demonstrate skeletal muscle properties like simple muscle twitch, quantal summation, wave summation, superposition, incomplete tetanus, complete tetanus, treppe, fatigue, and length-tension relationship.

Cleistanthus collinus leaf extracts are consumed for suicidal purposes in southern India. The boiled decoction is known to be more toxic than the fresh leaf juice. Although several compounds have been isolated and their toxicity tested, controversy remains as to which compounds are responsible for the high level of toxicity of C. collinus. We report herein that cleistanthoside A is the major toxin in the boiled aqueous extract of fresh leaves and causes death in rats in small doses. The toxicity of the boiled extract prepared in the manner described can be attributed entirely to cleistanthoside A. Cleistanthin A could also be isolated from the boiled extract, albeit in trace amounts. As hypotension not responding to vasoconstrictors is the cause of death in patients who have consumed the boiled extract, effects of cleistanthoside A on the determinants of blood pressure, namely, force of cardiac contraction and vascular resistance, were tested in isolated organ experiments. Cleistanthoside A has a direct vasoconstrictor effect; however, it inhibits ventricular contractility. Therefore, the notion that the shock in C. collinus poisoning is of vascular origin must be considered carefully, and the possibility of cardiogenic shock must be studied. We present the crystal structure of cleistanthin A and show the potency of fast NMR methods (NOAH4-BSCN-NUS) in the full spectral assignment of cleistanthoside A as a real-world sample of a natural product. We also compare the results of the NOAH4-BSCN-NUS NMR experiments with conventional NMR methods.

To carry out any research the first step is data gathering, as accuracy and prediction is depending on data. In the digital era, data generated at different sectors like banking, education, healthcare center or hospitals etc. is numerous which is helpful for researcher to carry out research. However, sharing data in plain text format, may compromise privacy of data. So, to maintain the privacy and secrecy of data this paper proposes RaEnOpti Approach, where optimized and secured data will be shared with researcher. This approach uses privacy preserving data mining, Encryption techniques and Genetic Algorithm for optimization work. This paper is discussing about the work in distributed network, as the data is collected from different healthcare centers.

This paper describes the process involved in conducting an online spirometry practical through Zoom. The teacher demonstrated the practical from the medical school, and the students observed the procedure from the comfort of their own homes. Students were able to analyze the graphs captured in the teacher's laptop by remotely controlling the teacher’s laptop. This method may be useful for places where face-to-face classes are suspended due to the COVID-19 pandemic.