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The American Journal of Physiology: Lung Cellular & Molecular Physiology is seeking papers on the topic of "Opioids and Respiratory Depression" in response to the opioid health crisis. The call for papers aims to address the dangerous side effect of respiratory depression caused by opioid overdose. The journal encourages researchers and healthcare professionals to submit articles and reviews related to breathing regulation and the detrimental consequences of opioids. The document is a list of references cited in an article discussing the prediction of opioid-induced respiratory depression using continuous capnography and oximetry, including studies on the effects of opioids on breathing, sleep-disordered breathing, risk factors, and the neurobiology of respiratory control. [Extracted from the article]

In the veterinary professional curriculum, methods of examination in many courses are transitioning from the traditional paper-based exams to electronic-based exams. Therefore, a controlled trial to evaluate the impact of testing methodology on examination performance in a veterinary physiology course was designed and implemented. Formalized surveys and focus group discussions were also used to determine student attitudes toward the examination formats. In total, 134 first-year veterinary students and 11 PhD/MS students were administered a total of 4 exams throughout 1 semester (2 on paper and 2 electronically) using a split-halves design. The paper (P) and electronic (E) exams contained 25 identical multiple-choice questions. Students were randomly assigned to two groups and were given exams in one of two sequences (E-P-E-P or P-E-P-E). Participants consented to and completed two anonymous surveys vis à vis their experience. Out of a maximum raw score of 25, the mean score for electronic examinations (20.8; 95% confidence interval, 20.3-21.2) was significantly ( P = 0.01) greater than that for paper examinations (20.3; 95% confidence interval, 20.0-20.7). However, students expressed numerous concerns with the electronic examination format, and, at the completion of the study, 87% preferred to take their examination on paper rather than the electronic format. These data show that student attitudes concerning the examination format are not primarily determined by examination results, and that the additional anxiety related to the electronic examination format plays a large role in student attitudes., (Copyright © 2017 the American Physiological Society.)

The five papers published by Hodgkin and Huxley in 1952 are seminal works in the field of physiology, earning their authors the Nobel Prize in 1963 and ushering in the era of membrane biophysics. The papers present a considerable challenge to the novice student, but this has been partly allayed by recent publications that have updated the reporting of current and voltage to reflect the modern convention and two books that describe the contents of the papers in detail. A disadvantage is that these guides contain hundreds of pages, requiring considerable time and energy on behalf of the reader. We present a concise guide to the Hodgkin and Huxley papers that includes only essential content, with the data presented in a linear and logical manner. We have color-coded figures for ease of understanding and included boxes that summarize key information for easy reference. It is our expectation that this article will act as an accessible introduction for students to the work of Hodgkin and Huxley and hopefully foster an appreciation for a fascinating story that repays in-depth study. NEW & NOTEWORTHY The Hodgkin and Huxley papers continue to inspire and intimidate, 70 years after their publication. The diverse subjects they cover include advanced experimental procedures, complex data analysis, calculus, and modeling, all of which ensure the papers can present a challenging read. We present a concise guide to the papers that includes only essential content depicted in color-coded graphs, allowing tracking of data from recordings to analysis and incorporation into the model to ease understanding. [ABSTRACT FROM AUTHOR]

Quantifying sweat gland activation provides important information when explaining differences in sweat rate between populations and physiological conditions. However, no standard technique has been proposed to measure sweat gland activation, while the reliability of sweat gland activation measurements is unknown. We examined the interrater and internal reliability of the modified-iodine paper technique, as well as compared computer-aided analysis to manual counts of sweat gland activation. Iodine-impregnated paper was pressed against the skin of 35 participants in whom sweating was elicited by exercise in the heat or infusion of methylcholine. The number of active glands was subsequently determined by computer-aided analysis. In total, 382 measurements were used to evaluate: 1) agreement between computer analysis and manual counts; 2) the interrater reliability of computer analysis between independent investigators; and 3) the internal reliability of sweat gland activation measurements between duplicate samples. The number of glands identified with computer analysis did not differ from manual counts (68 ± 29 vs. 72 ± 24 glands/cm(2); P = 0.27). These measures were highly correlated (r = 0.77) with a mean bias ± limits of agreement of -4 ± 38 glands/cm(2). When comparing computer analysis measures between investigators, values were highly correlated (r = 0.95; P < 0.001) and the mean bias ± limits of agreement was 4 ± 18 glands/cm(2). Finally, duplicate measures of sweat gland activation were highly correlated (r = 0.88; P < 0.001) with a mean bias ± limits of agreement of 3 ± 29 glands/cm(2). These results favor the use of the modified-iodine paper technique with computer-aided analysis as a standard technique to reliably evaluate the number of active sweat glands.

Glucose phosphorylation by hexokinase (HK) is a rate-limiting step in glucose metabolism. Regulation of HK includes feedback inhibition by its product glucose-6-phosphate (G6P) and mitochondria binding. HK affinity for G6P is difficult to measure because its natural product (G6P) inhibits enzyme activity. HK phosphorylates several hexoses, and we have taken advantage of the fact that 2-deoxyglucose (2-DG)-6-phosphate does not inhibit HK activity. By this, we have developed a new method for rapid radiochemical analysis of HK activity with 2-DG as a substrate, which allows control of the concentrations of G6P to investigate HK affinity for inhibition by G6P. We verified that 2-DG serves as a substrate for the HK reaction with linear time and concentration dependency as well as expected maximal velocity and KM. This is the first simple assay that evaluates feedback inhibition of HK by its product G6P and provides a unique technique for future research evaluating the regulation of glucose phosphorylation under various physiological conditions. NEW & NOTEWORTHY Traditionally, hexokinase activity has been analyzed spectrophotometrically in which the product formation of glucose-6-phosphate (G6P) is analyzed by an indirect reaction coupled to NADPH formation during conversion of G6P to 6-P gluconolactone. By nature, this assay prevents measurements of hexokinase (HK) affinity for inhibition by G6P. We have developed a rapid radiochemical filter paper assay to study HK affinity for G6P by use of radiolabeled 2-deoxyglucose as substrate to study physiological regulation of HK affinity for G6P-induced inhibition. [ABSTRACT FROM AUTHOR]

This paper describes how an anatomy and physiology laboratory class transitioned from a paper-based lab to an online learning platform that updated the curriculum to rely more on face-to-face small group collaboration and peer teaching. Student perceptions of the new format were positive, but halfway through the transition a global pandemic challenged the new instruction method. The face-to-face curriculum had to be adjusted to a virtual format that lacked in-person interaction between the instructor and the students. This switch to virtual labs had an adverse effect on both student perception and student performance in the second half of the semester. Our observations underscore the importance of creating an interactive community when teaching virtually. [ABSTRACT FROM AUTHOR]

History has been kind to Christian Bohr (1855-1911). His name is attached eponymously to three different areas of respiratory physiology. The first is the Bohr dead space, which refers to the portion of the tidal volume that does not undergo gas exchange. The second is the increase in oxygen affinity of hemoglobin caused by the addition of carbon dioxide to the blood. This is known as the Bohr effect and is a very important feature of gas exchange, both in the lung and in peripheral tissues. Both of these contributions by Bohr are familiar to most students. Bohr's third contribution refers to the calculation of the changes in the PO2 of blood as oxygen is loaded in the pulmonary capillary, the so-called Bohr integration. This contribution is less well known now, partly because of the advent of digital computing, but it was important in its day. The analysis is challenging because the very nonlinear shape of the oxygen dissociation curve means that the PO2 difference between the alveolar gas and the capillary blood, which is the driving pressure for diffusion, changes in a complicated way. All three papers are in German, and two of them are long and tedious to read. English translations are available, but few people read the papers, despite the fact that the first two articles are very frequently cited. In the present article, Bohr's contributions are reviewed, and some parts of the articles that are particularly difficult to understand are clarified. [ABSTRACT FROM AUTHOR]

Factors controlling cardiac sympathetic nerve activity (CSNA) in the normal state and those causing the large increase in activity in heart failure (HF) remain unclear. We hypothesized from previous clinical findings that activation of cardiac mechanoreceptors by the increased blood volume in HF may stimulate sympathetic nerve activity (SNA), particularly to the heart via cardiocardiac reflexes. To investigate the effect of volume expansion and depletion on CSNA we have made multiunit recordings of CSNA in conscious normal sheep and sheep paced into HF. In HF sheep (n = 9) compared with normal sheep (n = 9), resting levels of CSNA were significantly higher (34 [+ or -] 5 vs. 93 [+ or -] 2 bursts/100 heart beats, P < 0.05), mean arterial pressure was lower (76 [+ or -] 3 vs. 87 [+ or -] 2 mmHg; P < 0.05), and central venous pressure (CVP) was greater (3.0 [+ or -] 1.0 vs. 0.0 [+ or -] 1.0 mmHg; P < 0.05). In normal sheep (n = 6), hemorrhage (400 ml over 30 min) was associated with a significant increase in CSNA (179 [+ or -] 16%) with a decrease in CVP (2.7 [+ or -] 0.7 mmHg). Volume expansion (400 ml Gelofusine over 30 min) significantly decreased CSNA (35 [+ or -] 12%) and increased CVP (4.7 [+ or -] 1.0 mmHg). In HF sheep (n = 6) the responses of CSNA to both volume expansion and hemorrhage were severely blunted with no significant changes in CSNA or heart rate with either stimulus. In summary, these studies in a large conscious mammal demonstrate that in the normal state directly recorded CSNA increased with volume depletion and decreased with volume loading. In contrast, both of these responses were severely blunted in HF with no significant changes in CSNA during either hemorrhage or volume expansion. heart failure; sympathetic nervous system; hemorrhage; cardiac volume

The publication of a research paper in a journal completes the research activity and an unpublished research work is considered as incomplete in modern science activities. This trend of publishing originated in the seventeenth century. Henry Oldenberg in 1665 based on the ideology that science is a cooperative activity and 'growth of knowledge is incremental' , published in the first journal 'philosophical transactions' . The publication of research works in the form of small articles enable the development of science, as it enables other researchers to modify an experiment performed earlier and published in a journal.

The evolution of Forum for editing and peer-reviewing of articles that use mathematical modeling in biological science is the response of American Physiological Society to inadequate attention received by modeling papers in the past. The pioneering standards advocated by Gene Yates for authors and editors are further developed in the areas of sensitivity analysis and uniform nomenclature. Finding competent editors and reviewers and editorial delays are difficulties that need to be overcome.