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Introduction
Published in Wilmer W Nichols, Michael F O'Rourke, Elazer R Edelman, Charalambos Vlachopoulos, McDonald's Blood Flow in Arteries, 2022
The outstanding difference between the records obtained with Ludwig’s mercury manometer and Fick’s C-spring recorder was the magnitude of the fluctuations (or pulsations). How large they should be was unknown, and renewed efforts were made to increase the frequency response of the recording system. In 1883, Fick introduced his straight-spring manometer and recorded the first arterial pressure wave that showed a slight hint of a dicrotic notch, although Landois had already demonstrated the presence of a true dicrotic notch in 1874. He placed a small needle into a dog artery and directed the jet of blood onto the rotating drum of a kymograph. There, clearly displayed, was the dicrotic notch, along with systolic and diastolic pressures. Landois called his record a “hemautograph”. The development of reliable manometers that could accurately measure pulsatile blood pressure had to await Otto Frank’s great work of 1903.
K
Published in Anton Sebastian, A Dictionary of the History of Medicine, 2018
Kymograph [Greek: kyma, wave + graphein, to write] Device to measure pressure, muscle movements and other parameters in experimental physiology. The principle and use of it was first suggested by the English physician, Thomas Young (1773–1829), in 1807. The apparatus was first constructed and used by Carl Frederick Ludwig (1816–1895) of Germany in 1849. It consisted of smoked paper fixed on a rotating drum on which recordings were made with a stylus.
Experiment and experience in anaesthesia: Alfred Goodman Levy and chloroform death, 1910–1960
Published in Christopher Lawrence, Medical Theory, Surgical Practice, 2018
The first announcement of Levy’s views came in January 1911, when he claimed that sudden chloroform death was caused, not by overdosage, but by the action of a small amount of chloroform on the heart, by too light a dosage. This was a position Levy defended in print over the next fifteen years. The claims were based on animal experimentation and, later and increasingly, on clinical evidence. The initial account of his chloroform experiments was made as a preliminary communication to the Physiological Society. Levy reported nine deaths in cats under light (0.5 per cent to 1.5 per cent) chloroform anaesthesia. In two instances blood pressure and respiration were recorded on a kymograph at the moment of death. The tracings showed, he said, that ‘The heart failure was absolutely sudden’. At the moment before death the heartbeat (as recorded by the mercury manometer) was ‘always rapid’. The respiratory tracing showed, after the heart had stopped, ‘a few powerful convulsive gasps’. Levy reported that he had discussed the records with Arthur Cushny, Professor of Pharmacology at University College, London. Cushny had suggested that Levy repeat the experiments and look for ventricular fibrillation. Levy reported three subsequent experimental deaths in which ‘I found the ventricles dilated and fibrillating’. He concluded, ‘The impression I gained from a review of all the cases was that the heart, under light chloroform administration, may become incapable of accommodation to vascular strain.’ This view, he argued, was confirmed when adrenalin was injected under light anaesthesia and similar curves were obtained. Thirteen out of fifteen cats collapsed and in every instance of death (eleven) the ventricles ‘were dilated and fibrillating’. Section of the vagi and the subcutaneous injection of atropine did not protect against death but, he concluded, ‘Full chloroform anaesthesia appears to be absolutely protective.’ He reported that he had been unable to obtain the reaction under ether.16 On 21 October of the same year Levy made a further communication on the subject. He reported that cats were liable to die from the same cause when recovering from fully established anaesthesia. He concluded, ‘By administering a vapour of 2 per cent or thereabouts, in a perfectly continuous fashion, cats may be anaesthetized without any risk.’17
The transnational move of interdisciplinarity: Ginseng and the beginning of neuroscience in South Korea, 1970–1990s
Published in Journal of the History of the Neurosciences, 2022
Park was a pharmacologist who received his Ph.D. in 1970 in the College of Medicine at Seoul National University. His dissertation examined “the effects of diphenylhydantoin and ouabain on ATPase activity in rat erythrocyte membranes,” the “alkaloid of Glycyrrhiza glabra L.,” and the effect of “ginseng on experimental hypertension” (Park 1970). Park was interested in revealing the way materials like ouabain, Glycyrrhiza glabra L, and ginseng worked in the human body, but he remembered being frustrated by South Korea’s poor research environment. “The only instrument we had was kymography,” he recalled. He asked himself, “What could [I] have done in such a poor experiment?” (Park 2009, 198). After completing his Ph.D., Park remained at Seoul National University as a basic medical researcher. In the 1970s, among the many materials that interested him, he began to focus on the biomedical effects of herbs such as aconite, acanthopanax, and ginseng.
Effect of Microtubule Disruption on Dynamics of Acidic Organelles in the Axons of Primary Cultured Retinal Ganglion Cells
Published in Current Eye Research, 2018
Seiji Miyake, Yuji Takihara, Satoshi Yokota, Yoshihiro Takamura, Masaru Inatani
To create the kymographs and process the movies, the open source software project Fiji (an image processing package including ImageJ and the bundling of numerous plugins)16 was used. Overall transport of acidic components was quantified from the kymographs, which represent the movement obtained from time-lapse movies. To determine the velocities per acidic organelle, moving distance and elapsed time of each acidic organelle were calculated. Using line selection tool located on the toolbar of ImageJ, the angle and length of selected lines, which traced the movement of individual acidic organelle, were overlaid on the kymograph. Moving distance and time were calculated from two obtained values of respective acidic compartment using spreadsheet software (Excel) (Microsoft Corporation, Washington, USA) with a trigonometric function. Finally, to calculate velocity, moving distance was divided by moving time. Observed organelles were classified into four groups: anterograde (velocity of ≥0.05 µm/s), retrograde (velocity of ≥0.05 µm/s), stationary (velocity < 0.05 µm/s), and fluttering (distance of ≤10 μm and velocity of ≥0.05 µm/s), in accordance with previous reports.15,17 The velocity is indicated as mean ± SE.
The early history of the knee-jerk reflex in neurology
Published in Journal of the History of the Neurosciences, 2022
The apparatus used by Bowditch and Warren (1890, 28) is shown in Figure 3. It is instructive because it shows the orientation of the subject that allowed his leg to swing horizontally. The same leg orientation was used by Lombard (1887a). The heel of the shoe of the subject can be seen to be connected to a pen (shown at P) with a system of levers that reduces the leg extension to accommodate recording on the kymographic cylinder (shown below C). The component of the apparatus to the right of the kymograph is a small pendulum myograph used to record the time between the sounding of the bell and the onset of the hammer strike. The bell is at B, to the right of the myograph.