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11.
D W Yates 《BMJ (Clinical research ed.)》1990,301(6760):1090-1094
12.
Physical mapping of deletion breakpoints in patients with X-linked ichthyosis: evidence for clustering of distal and proximal breakpoints 总被引:1,自引:0,他引:1
R S Newman N A Affara J R Yates M Mitchell M A Ferguson-Smith 《Proceedings. Biological sciences / The Royal Society》1990,242(1305):231-239
Previous studies have shown that approximately 80% of patients with X-linked ichthyosis have a total deletion of the steroid sulphatase (STS) locus which lies in Xp22.3-Xpter. We show by Southern analysis that a common core of sequences are absent in 78.6% of our cases, suggesting that the deletion breakpoints may be highly clustered. To characterize the region in more detail a long-range physical map of over 3 megabases (Mb) surrounding the STS locus was constructed using pulse-field gel electrophoresis. The map enabled the order of sequences tel-SI19-GMGXY3-[STS,GMGXY19]-GMGX9-[dic56 ,SIII2]-cen and the localization of the deletion breakpoints to be established. In ten cases the pulse-field evidence supports the clustering of breakpoints and indicates a deletion size of 2 Mb in most patients. Five CpG islands have been positioned around the STS locus and may be associated with other loci in the region involved in mental retardation and Kallman's syndrome. The map will be instrumental in an attempt to isolate and characterize the deletion breakpoints and to access other genes located in the region. 相似文献
13.
Akhlaq A. Farooqui Tahira Farooqui Allan J. Yates Lloyd A. Horrocks 《Neurochemical research》1988,13(6):499-511
Protein kinase C has recently attracted considerable attention because of its importance in the control of cell division, cell differentiation, and signal transduction across the cell membrane. The activity of this enzyme is altered by several lipids such as diacylglycerol, free fatty acids, lipoxins, gangliosides, and sulfatides. These lipids may interact with protein kinase C either directly or through calcium ions and produce their regulatory effect (activation or inhibition) on the activities of the enzymes phosphorylated by this kinase. These processes widen our perspective of the regulation of intercellular and intracelluular communication.Abbreviations used (PK-C)
Protein kinase C
- (cAMP-PK)
cAMP dependent protein kinase
- (DAG)
diacylglycerol
- (PtdSer)
phosphatidylserine
- (InsP
3)
inositol 1,4,5-trisphosphate
- (PtdIns 4,5-P2)
inositol 4,5 bisphosphate
- (FFA)
free fatty acid
- (MBP)
myelin basic protein
- (ATP)
adenosine triphosphate
- (GTP)
guanine triphosphate
- (TPA)
12-tetradecanoylphorbol-13-acetate
- (EGF)
epidermal growth factor
- (PDGF)
platelet derived growth factor
- (NeuNAc)
and N-acetylneuraminic acid 相似文献
14.
A rabbit antiserum to the C-terminus of the putative brain amyloid precursor was used to probe Western blots of tissue proteins separated by SDS-PAGE. The antiserum specifically labelled a protein of approx. 70 kDa in the Tris buffer-soluble fraction of brain samples from rat, Alzheimer subjects, cases of young and old Down's syndrome, and age-matched controls. The 70 kDa protein was present in low concentrations in human liver and kidney, and was undetectable in human skeletal muscle. The 70 kDa protein may be a metabolite of the amyloid precursor. 相似文献
15.
F E Yates 《Federation proceedings》1983,42(15):3143-3149
In this paper the general properties of homeostatic variables are discussed, and it is shown that mean state regulation must be defined over some stated epoch and that the variance associated with such regulation can permit maximum/minimum variations of 2:1. Dynamic regulation is then contrasted with (automatic) control, and mean systemic arterial pressure (MSAP) in mammals is shown to be under dynamic regulation in the long run, although it may be under control in the short run. The discussion is next developed around the branching rules for mammalian arterial trees. The heart and lymphatic system are introduced as separate, zero-back-pressure, sump pumps that "ground" central venous pressure and interstitial pressure, respectively. Hydraulic flow arguments, combined with arterial tree branching rules, are used to demonstrate the short-circuit character of the renal circulation, and the peculiar distribution of pressure drops within it. From that peculiar distribution it is proposed that there is a nonanatomic, functional resistance located approximately at the region of efferent arterioles, which adds 15 mm Hg of hydrostatic pressure, upstream, to the central arteries. The chief aim of the paper is to raise certain questions about inconsistencies in data about renal circulation, to suggest a resolution, and to show how MSAP is set at (approximately) 100 mm Hg. 相似文献
16.
J W Yates L B Gladden M K Cresanta 《Journal of applied physiology (Bethesda, Md. : 1985)》1983,55(3):891-896
The isometric endurance of the elbow flexors was determined in a control condition and subsequent to a maximal effort exercise bout on a cycle ergometer in seven subjects. Maximum voluntary contraction (MVC), peak rate of tension development (+dP/dt), peak rate of tension relaxation (-dP/dt), one-half contraction time, and one-half relaxation time were also measured. Each subject was tested on four occasions: two control and two experimental sessions. During the control sessions each subject held 40% of MVC to exhaustion, whereas the experimental session included a 1-min maximal effort exercise bout on a cycle ergometer 6 min prior to the isometric endurance task. Arterialized blood samples were drawn and analyzed for lactate, pH, PCO2, and PO2. Plasma bicarbonate was calculated from the Henderson-Hasselbalch equation. Subsequent to the cycle ergometer bout, blood lactate concentration rose from 0.8 to 11 mM, pH decreased from 7.43 to 7.20, PCO2 decreased from 40 to 32 Torr, and plasma bicarbonate decreased from 26 to 12 mM. When compared with the control values, no significant changes were evident for any muscle contractile properties following the cycle ergometer bout. However, isometric endurance was significantly reduced from 115.0 +/- 7.2 to 86.3 +/- 7.3 s.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
17.
Cytological Detection of the c25H Deletion Involving the Albino (c) Locus on Chromosome 7 in the Mouse 总被引:4,自引:2,他引:2
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D. A. Miller V. G. Dev R. Tantravahi O. J. Miller M. B. Schiffman R. A. Yates S. Gluecksohn-Waelsch 《Genetics》1974,78(3):905-910
A deletion of the albino (c) locus on mouse chromosome 7 has been demonstrated using Q- and G-banding methods in a mouse heterozygous for the radiation-induced lethal albino allele, c(25H). The deletion, which is thought to be 1-6 cM long, represents about 7.6% of the length of the metaphase chromosome. 相似文献
18.
The identification of intermediates in the reaction of pig heart lactate dehydrogenase with its substrates 总被引:9,自引:9,他引:0
J. R. Whitaker D. W. Yates N. G. Bennett J. J. Holbrook H. Gutfreund 《The Biochemical journal》1974,139(3):677-697
Pig heart lactate dehydrogenase was studied in the direction of pyruvate and NADH formation by recording rapid changes in extinction, proton concentration, nucleotide fluorescence and protein fluorescence. Experiments measuring extinction changes show that there is a very rapid formation of NADH within the first millisecond and that the amplitude of this phase (phase 1) increases threefold over the pH range 6-8. A second transient rate (phase 2) can also be distinguished (whose rate is pH-dependent), followed by a steady-state rate (phase 3) of NADH production. The sum of the amplitudes of the first two phases corresponds to 1mol of NADH produced/mol of active sites of lactate dehydrogenase. Experiments that measured the liberation of protons by using Phenol Red as an indicator show that no proton release occurs during the initial very rapid formation of NADH (phase 1), but protons are released during subsequent phases of NADH production. Fluorescence experiments help to characterize these phases, and show that the very rapid phase 1 corresponds to the establishment of an equilibrium between E(NAD) (Lactate) right harpoon over left harpoon H(+)E(NADH) (Pyruvate). This equilibrium can be altered by changing lactate concentration or pH, and the H(+)E(NADH) (Pyruvate) species formed has very low nucleotide fluorescence and quenched protein fluorescence. Phase 2 corresponds to the dissociation of pyruvate and a proton from the complex with a rate constant of 1150s(-1). The observed rate constant is slower than this and is proportional to the position of the preceding equilibrium. The E(NADH) formed has high nucleotide fluorescence and quenched protein fluorescence. The reaction, which is rate-limiting during steady-state turnover, must then follow this step and be involved with dissociation of NADH from the enzyme or some conformational change immediately preceding dissociation. Several inhibitory complexes have also been studied including E(NAD+) (Oxamate) and E(NADH) (Oxamate') and the abortive ternary complex E(NADH) (Lactate). The rate of NADH dissociation from the enzyme was measured and found to be the same whether measured by ligand displacement or by relaxation experiments. These results are discussed in relation to the overall mechanism of lactate dehydrogenase turnover and the independence of the four binding sites in the active tetramer. 相似文献
19.
ELECTRON MICROSCOPIC RADIOAUTOGRAPHIC STUDIES OF THE CAROTID BODY FOLLOWING INJECTIONS OF LABELED BIOGENIC AMINE PRECURSORS 总被引:3,自引:1,他引:2
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Adult Syrian hamsters were given a subcutaneous injection of reserpine 3 days before an intraperitoneal injection of 3H-3,4 dihydroxyphenylalanine or 3H-5, hydroxytryptophan and the carotid bodies were subsequently prepared for electron microscopic radioautography. Other Syrian hamsters were given a subcutaneous injection of reserpine and the carotid bodies were subjected to a sensitive cytochemical test for the detection of unsubstituted amines. These studies were made to determine whether the labeled amine precursors were incorporated into the cells and to see whether the parenchymal cells were affected by reserpine treatment. Material from hamsters treated first with reserpine and subsequently injected with 3H-3,4 dihydroxyphenylalanine or 3H-5, hydroxytryptophan exhibited reduced grains of silver over the cells which were associated mainly with the dense cores of the cytoplasmic granules. These studies offer evidence that the granules of the carotid body incorporate catecholamine and indolamine precursors. Material from hamsters incubated for the presence of unsubstituted amines gave a positive reaction (opaque cytoplasmic granules) for catecholamines but not for indolamines. The latter substances may not be present in quantities sufficient to register a positive reaction in the cytochemical test. The opaque granules, indicative of the presence of catecholamines, decreased in density after reserpine treatment. 5 days after one reserpine injection the granules had regained opacity and were comparable to those seen in the control cells. 相似文献
20.