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Summary and Development of a New Approach to Senescence
Published in Nate F. Cardarelli, The Thymus in Health and Senescence, 2019
Sacher in his evolutionary-comparative hypothesis relates aging to the cephalization index (brain weight/body weight). Life-span is proportional to brain size, which may mean the relationship is to intellect. Sacher thus arrives at two concepts which are pursued in this text: (1) there is a relationship between aging and the brain and (2) there are longevity assurance genes and not senescent genes.
ENTRIES A–Z
Published in Philip Winn, Dictionary of Biological Psychology, 2003
Note well that there are some difficulties with terminology: CEPHALIZATION is used to indicate the degree to which an animal has developed a head, with specialized sensory receptors, feeding organs and, perhaps most importantly, a concentration of neural tissue (either a head ganglion or a brain). The term ENCEPHALIZATION has been used in three ways. (i) It is a simple index of the degree to which the CEREBRAL CORTEX has developed. (ii) Encephalization has been used to describe the degree to which more recently evolved tissue—the cerebral cortex and particularly the NEOCORTEX—has taken over functions that were previously regulated by structures further down the NEURAXIS. It remains uncertain to what degree functions are 'taken over' as opposed to 'made more sophisticated' (that is, do older and newer structures combine with each other or do newer structures comprehensively take over the functions of older ones?). (iii) The word encephalization features in the ENCEPHALIZATION QUOTIENT (EQ) which is the ratio of log brain mass to log body mass. The encephalization quotient assumes that animals that are in some sense more intelligent (see INTELLIGENCE) have brains that are relatively larger in proportion to their body size compared to rather less intelligent animals. It is a measure that was introduced in the 1970s by H.J.Jerison, and was initially used in assessment of the likely intelligence of extinct animals, principally, of course, dinosaurs (see PALAEONEUROLOGY; DINOSAUR BEHAVIOR). It is a relatively crude measure: later authors interested in determining the relative intelligence of different species have taken measures such as a NEOCORTEX RATIO, the ratio of neocortical mass to the total brain mass. Similar measures could be taken for any identifiable brain structure.
Caenorhabditis elegans in Computational Research
Published in Theodore B. Achacoso, William S. Yamamoto, AY's Neuroanatomy of C. elegans for Computation, 2022
Theodore B. Achacoso, William S. Yamamoto
In parallel, when a vertex adjacency matrix is used as a mathematical object in the investigation of individual neurons, presynaptic neurons become row labels, postsynaptic neurons become column labels, and a synapse or matrix element is represented by a dot or a pixel in a computer screen. If color is available, synaptic density (the number of times any two neurons are synaptically connected) may be coded in the color of each dot or pixel. This same representation may also be done with gap junctions (Figure 1.11). The vertex adjacency matrix, chosen in this case as the mathematical object by which to study anatomical data, may again be manipulated through specific rules governing matrices. For example, by rearranging the order of rows and columns, certain overall characteristics of the nerve net can be made prominent (Figures 1.12 to 1.16). The sequence of neurons in the rows is the same as that in the columns for each topological equivalent. It is seen that random ordering of neurons in the rows and columns (Figure 1.12) corresponds to an unstructured nervous system. Anteroposterior sequence (Figure 1.13) and ganglionic order (Figure 1.14) of the neurons delineate the long and short tracts of the nervous system, and visually show cephalization, i.e., areas suspected of increased organization and function have more synaptic connections. This information is useful for any future attempts to fabricate electromechanically the synaptic connectivity of this worm, as components with short tracts can be grouped together, and long tracts can be grouped in a bus or back plane. The result of left-right arrangement of neurons in the matrix (Figure 1.15) suggest that lateralization exists, and may provide basis for the dextro- or sinistraversion of the worm during locomotion. Categorizing neurons as sensory (S), motor (M), and interneurons (I) in the matrix (Figure 1.16) shows dense connections between S to I, I to I, and I to M, and this may suggest the validation for the three-layer artificial neural network design.
Assessing congestion in acute heart failure using cardiac and lung ultrasound - a review
Published in Expert Review of Cardiovascular Therapy, 2021
Øyvind Johannessen, Peder L. Myhre, Torbjørn Omland
Guidelines recommend chest x-ray in patients with suspected AHF, despite the limited diagnostic sensitivity for pulmonary congestion [6]. Typical findings associated with pulmonary congestion include cardiomegaly, redistribution, interstitial edema, and pleural effusions. These signs have been found to have low accuracy for diagnosing pulmonary congestion, defined as increased PCWP, resulting in abnormal accumulation of fluid in the lungs [20,22]. Chakko et al. reported chest radiographs ability to detect PCWP ≥ 20 mmHg: cardiomegaly had specificity 97% and sensitivity 10%; redistribution specificity 68% and sensitivity 60%; interstitial edema specificity of 73% and sensitivity 60% and pleural effusion specificity 79% and sensitivity 43% [22]. In the Breathing Not Properly study, cardiomegaly (specificity 80% and sensitivity 79%) and cephalization (specificity 96% and sensitivity 41%) was the most accurate chest x-ray indicators of AHF in patients presenting with acute dyspnea in the ED [26]. In patients from the ADHERE study, 15,937 patients (19%) of the total 85,376 patients with AHF had a negative chest x-ray for signs of pulmonary congestion [7]. There are several explanations for this inaccuracy of chest radiographs to detect pulmonary edema, including technical issues, patient positioning, similarity in radiolucent material (i.e. blood and pus) and inability to detect effusion below a certain threshold of fluid accumulation [12].
Catecholamine-induced reverse takotsubo cardiomyopathy
Published in Baylor University Medical Center Proceedings, 2019
Shivani Bhat, Hashim Gazi, Victor Mwansa, Lovely Chhabra
A 27-year-old man presented to the emergency room with worsening dyspnea, chest pressure, and a pruritic erythematous rash extending from his axilla to anterior abdominal wall after a brown recluse spider bite. Vital signs on admission revealed a blood pressure of 130/80 mm Hg, respiratory rate of 20 breaths/min, and heart rate of 106 beats/min. He had dyspnea and mild to moderate respiratory distress associated with wheezing and an oxygen saturation of 93% on room air. He was treated for anaphylaxis and subacute angioedema. After partial clinical response to intravenous diphenhydramine and methylprednisolone, an emergent order for intramuscular epinephrine, dose 0.3 mg (1:1000 solution), was placed. The formulation, however, was inadvertently administered intravenously by the nurse. The patient developed intractable cough, chest tightness, pallor, and frank hemoptysis resulting in acute hypoxemic respiratory failure (Figure 1) and required emergent mechanical ventilator support. The endotracheal tube aspirate was dark bloody-red tinged, and the chest radiograph showed bilateral dense infiltrates and early cephalization.
A literature review of immersion pulmonary edema
Published in The Physician and Sportsmedicine, 2019
Manish Kumar, Paul D. Thompson
The chest radiograph may be normal especially (up to) within 12–18 h’ post-event, [2,14] but may show typical signs of pulmonary edema [3,11] such as cephalization, Kerley B lines, [5] ground glass abnormalities, [10] infiltrates [13,26] especially on the dependent side because of higher blood flow and pressure gradients due to gravity [5,14,26]. CT scans are more sensitive than chest radiographs [9,27] and findings range from pleural effusion to ground glass opacities limited to a few areas of the lung to interlobular septal thickening [9].