Alterations In Water Content Research Articles

Isoenzymes of Human Skeletal Muscle Hexokinase in Muscular Dystrophy

Conference Article| October 01 1974 Isoenzymes of Human Skeletal Muscle Hexokinase in Muscular Dystrophy JENNIFER M. STRICKLAND; JENNIFER M. STRICKLAND 1Midland Centre for Neurosurgery and Neurology, Holly Lane, Smethwick, Warley, Worcs. B67 7JX, U.K. Search for other works by this author on: This Site PubMed Google Scholar DAVID A. ELLIS DAVID A. ELLIS 1Midland Centre for Neurosurgery and Neurology, Holly Lane, Smethwick, Warley, Worcs. B67 7JX, U.K. Search for other works by this author on: This Site PubMed Google Scholar Biochem Soc Trans (1974) 2 (5): 1125–1127. https://doi.org/10.1042/bst0021125 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Cite Icon Cite Get Permissions Citation JENNIFER M. STRICKLAND, DAVID A. ELLIS; Isoenzymes of Human Skeletal Muscle Hexokinase in Muscular Dystrophy. Biochem Soc Trans 1 October 1974; 2 (5): 1125–1127. doi: https://doi.org/10.1042/bst0021125 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Society Transactions Search Advanced Search This content is only available as a PDF. © 1974 Biochemical Society1974 Article PDF first page preview Close Modal You do not currently have access to this content.

Periventricular water content. Effect of pressure in experimental chronic hydrocephalus.

VARIOUS studies on dogs,1cats,2and rabbits3have demonstrated that the total water content of normal adult brain is in the vicinity of 80%, with gray matter having a somewhat higher and white matter some-what lower content. Several investigators, using a number of different techniques, have estimated the size of the extracellular space of the brain.4,5Currently, general agreement exists that the inulin space, as representative of the extracellular space, is approximately 7% to 20% of the normal cerebrum.4-6 Alterations of water content in the periventricular white matter have been shown by Fishman and Greer.7They demonstrated an increased water content in experimental hydrocephalus. (We define hydrocephalus as the enlargement of the ventricular system associated, at least at some point of its history, with increased intracranial pressure.) In those studies, however, no attempt was made to determine the source or compartmentation of

Properties of cements mixed from liquids with altered water content

The water content of the liquids of silicate, zinc phosphate, and silicophosphate cements was altered within the range of plus 10 to minus 10 per cent. Tests were run on the cements mixed from these liquids and the results of these tests compared with data obtained by testing cements mixed from the unaltered liquids. The following observations are made: 1. The setting times of zinc phosphate and silicophosphate cements are increased with increases in water of the liquids whereas the setting time of silicate cements is increased by a decrease in the water content of these liquids. 2. Cements mixed with liquids having altered water content have reduced physical properties, such as a marked reduction in abrasion resistance and increased solubility. 3. The results of the investigation emphasize protection of cement liquids from alteration in water content in order to maintain maximum physical properties of the cement mixes.

The Behaviour of Saturated Clays During Sampling and Testing

Synopsis An experimental investigation leads to the conclusion that if two identical specimens of saturated clay are subjected to different changes in total stress without alteration in water content, and if the strains consequent upon these stress changes cause little alteration in micro-structure, then the undrained strengths of the two specimens will be practically identical. Thus, since there is no water content change during sampling, the undrained strength of a sample of saturated clay will be closely equal to the strength in the ground, provided the strains during sampling are not sufficiently large to cause significant micro structural changes. This result helps to explain the success of the φ = 0 analysis in “end of construction” problems (at least in saturated, intact clays without a very sensitive structure) even though the effective stress in a sample may be considerably less than the average effective stress acting in the ground at the depth from which the sample was obtained. Une enquête expérimentale amène à conclure que si deux spécimens identiques d'argile saturée sont soumis à des changements de tension totale différents sans varier la teneur en eau, et si les tensions résultantes de ces changements de tension occasionnent peu de changement dans la microstructure, les résistances à teneur en eau constante des deux spécimens seront alors pratiquement identiques. Par conséquent, puisqu'il n'y a pas de changement de la teneur en eau pendant le prélèvement d‘échantillons, la résistance à teneur en eau constante d'un échantillon d'argile saturée sera très proche de la résistance dans le sol, pourvu que les déformations lors du prélèvement d'échantillons ne soient pas suffisamment grandes pour occasionner des changements significatifs dans la microstructure. Ce résultat aide à expliquer le succès de l'analyse φ = 0 dans les problèmes de “fin de construction” (au moins dans les argiles saturées intactes sans structure très sensible) même si la tension effective d'un èchantillon est beaucoup moins que la tension effective moyenne dans le sol à la profondeur à laquelfe on a prélevé l'échantillon.

The respiration and composition of the mammary gland of the guinea pig during pregnancy and lactation

The respiration and composition of the mammary gland have been studied in pregnant and lactating guinea pigs. Endogenous respiration of surviving slices increased significantly after parturition, fourfold on a dry-weight basis, twofold on a defatted dry-weight or fresh-weight basis. The changes were also significant when referred to tissue nitrogen, protein, or DNA. Similar increases in respiration were not noted in liver, kidney, spleen, heart, or adrenal. Addition of succinate resulted in marked stimulation of slice respiration of glands from post partum animals and during pregnancy when calculated on a defatted dry-weight basis. Pyruvate was effective only in animals 10 or 20 days post partum. Acetate produced significant stimulation in animals 10 days post partum and during pregnancy when calculated on a defatted dry-weight basis. The total nitrogen and protein content of the gland increased markedly at parturition, then declined as lactation waned. DNA remained fairly constant over the period of these experiments. The fat content of the gland decreases after parturition, but no alteration in water content occurs. Slices of glands from lactating animals lose dry matter content both during preparation and incubation, while those from pregnant animals lose dry matter only during incubation. The results have been discussed in light of data in the literature, and a tentative evaluation of the various bases for expression of metabolic activity has been made.

PROTOPLASMIC VISCOSITY CHANGES IN DIFFERENT REGIONS OF THE GRASSHOPPER NEUROBLAST DURING MITOSIS

Observations on the rapidity of brownian movement of the mitochondria in different regions of the grasshopper neuroblast during the entire mitotic cycle indicate that:1) The viscosity of all parts of the cytosome is relatively high during interphase and prophase, begins to fall in late prophase, reaches a minimum at anaphase, and rises gradually to its original high level during telophase.2) The viscosity of the portion of the spindle between the pole and the plane in which the proximal ends of the chromosomes are situated appears to fall slightly from a high prometaphase level through anaphase.3) The viscosity of the portion of the spindle situated between the separating daughter chromosome groups shows, during anaphase, a slight drop from a medium value, and this is followed at the beginning of telophase by an abrupt rise to a very high level, which is maintained through early and middle telophase. Alterations in water content and nucleic acid content of the cytoplasm are suggested as possible explanations of viscosity changes during mitosis.