Showing papers by "Newcastle University published in 1968"
TL;DR: The brain scans from 50 cases of proven dementia in old age were examined and various features objectively assessed, and compared with similar features in a group of non-demented (controls) old people.
1,853 citations
1,429 citations
TL;DR: In this article, a method was devised in which the specific hydrolysis of starch completely to glucose is achieved by means of an amyloglucosidase, and the contents of α-linked glucose polymers in a number of biological samples were determined.
Abstract: A review of methods available for the determination of starch suggested, for reasons given, that none was satisfactory for the determination of α-linked glucose polymers in biological materials. Therefore, a method was devised in which the specific hydrolysis of starch completely to glucose is achieved by means of an amyloglucosidase. Glucose is estimated using glucose oxidase. Contents of α-linked glucose polymers in a number of biological samples were determined, and compared with those obtained using 0.36 N-H2SO4 to effect hydrolysis.
396 citations
TL;DR: The theory of marginal convection in a uniformly rotating, self-gravitating, fluid sphere, of uniform density and containing a uniform distribution of heat sources, is developed to embrace modes of convection which are asymmetric with respect to the axis of rotation.
Abstract: The theory of marginal convection in a uniformly rotating, self-gravitating, fluid sphere, of uniform density and containing a uniform distribution of heat sources, is developed to embrace modes of convection which are asymmetric with respect to the axis of rotation It is shown that these modes are the most unstable, except for the smallest Taylor numbers, T (a measure of the rotation rate); ie for any T and o) (Prandtl number), the lowest Rayleigh number (a measure of the temperature gradients in the sphere) is associated with an asymmetric motion This is demonstrated both by an expansion method suitable for small T, and by asymptotic theory for T oo For large T, the eigenmode most easily excited is small in amplitude everywhere except near a cylindrical surface, of radius about half that of the sphere, and coaxial with the diameter parallel to the angular velocity vector
338 citations
TL;DR: Thyroglobulin antibodies and complement‐fixing antibodies are significantly associated with vitiligo as compared with psoriasis, and there is no evidence that thyroid autoimmunity is associated positively or negatively with Psoriasis.
Abstract: SUMMARY There is a significant association between vitiligo and thyroid disease Thyroglobulin antibodies are significantly associated with vitiligo, whether patients with psoriasis or a general practice population are taken as controls Similarly complement-fixing antibodies are significantly associated with vitiligo as compared with psoriasis There is no evidence that thyroid autoimmunity is associated positively or negatively with psoriasis Alopecia areata, pernicious anaemia and diabetes mellitus are also significantly associated with vitiligo
260 citations
TL;DR: C-substance from seven other strains of Pneumococcus possesses a structure common to that described for the strain 1-192R, and in the remaining seven cases the contaminating C- Substance was probably similarly constituted.
Abstract: 1 Pneumococcal C-substance was isolated from the non-capsulated Pneumococcus 1–192R, ATCC 12213, by extraction with trichloroacetic acid solution followed by chromatography on DEAE-cellulose (HCO3− form) 2 The polymer contains 7·0% of phosphorus and 6·0% of nitrogen and is composed of phosphate, N-acetyl-d-galactosamine, d-glucose, N-acetyldiaminotrideoxyhexose, ribitol and choline in the molecular proportions 2:1:1:1:1:1 3 After acid hydrolysis, d-galactosamine hydrochloride and galactosamine 6-phosphate were isolated in crystalline form and crystalline derivatives of d-glucose and anhydroribitol were obtained A product of partial acid hydrolysis was provisionally characterized as 6′-O-phosphoryl-[O-β-d-galactosaminyl-(1′→6)-d-glucose] 4 C-substance contains free amino groups accessible to attack by 1-fluoro-2,4-dinitrobenzene and nitrous acid 5 Choline phosphate and ribitol phosphate are units in the polymer 6 Treatment with hot alkali gave a fragment comprising phosphate, d-galactosamine, d-glucose, diaminotrideoxyhexose and ribitol in the molecular proportions 2:1:1:1:1 7 After selective N-acetylation, the fragment contained one of its phosphate groups as a phosphomonoester and one as a phosphodiester, shown by potentiometric titration and by treatment with a phosphomonoesterase 8 C-substance from seven other strains of Pneumococcus possesses a structure common to that described for the strain 1–192R 9 Capsular materials from 26 different strains of Pneumococcus were analysed for suspected contamination by C-substance In 19 cases the presence of C-substance with the normal structure was demonstrated, and in the remaining seven cases the contaminating C-substance was probably similarly constituted 10 F-substance was isolated and the associated fatty acid material analysed
183 citations
TL;DR: In this paper, a plane polarised light reflection technique was used to measure the refractive and absorption indices of a series of carbons in the wavelength region one to ten microns at room temperature.
178 citations
TL;DR: In this paper, constitutive equations for cholesteric liquid crystals are formulated based on conservation laws proposed by Ericksen (1961), and an entropy inequality of the type discussed by Muller (1967) is employed.
Abstract: On the basis of conservation laws proposed by Ericksen (1961), constitutive equations are formulated for cholesteric liquid crystals. To motivate the choice, an entropy inequality of the type discussed by Muller (1967) is employed. Apart from minor differences, the hydrostatic theory of Ericksen (1962) is obtained, and proposals are made for the non-equilibrium terms. With this theory, the spinning phenomenon noted by Lehmann (1900) is investigated, and it is shown that solutions similar to his observations arise in a natural way.
172 citations
TL;DR: The metabolic pathways of aromatic-ring fission were examined in a range of fungal genera that utilize several compounds related to lignin, suggesting the existence of a ;meta' type of ring cleavage among fungi.
Abstract: 1. The metabolic pathways of aromatic-ring fission were examined in a range of fungal genera that utilize several compounds related to lignin. 2. Most of the genera, after growth on p-hydroxybenzoate, protocatechuate or compounds that are degraded to the latter (e.g. caffeate, ferulate or vanillate), rapidly oxidized these compounds, but not catechol. 3. Such genera possessed a protocatechuate 3,4-oxygenase and accumulated beta-carboxymuconate as the product of protocatechuate oxidation. This enzyme had a high pH optimum in most organisms; the Rhodotorula enzyme was competitively inhibited by catechol. 4. beta-Carboxymuconate was converted by all competent fungi into beta-carboxymuconolactone, which was isolated and characterized. None of the fungi produced or utilized at significant rates the corresponding bacterial intermediate gamma-carboxymuconolactone. 5. The lactonizing enzymes of Rhodotorula and Neurospora crassa had a pH optimum near 5.5 and approximate molecular weights of 19000 and 190000 respectively. 6. The fungi did not degrade the isomeric (+)-muconolactone, gamma-carboxymethylenebutanolide or beta-oxoadipate enol lactone at significant rates, and thus differ radically from bacteria, where beta-oxoadipate enol lactone is the precursor of beta-oxoadipate in all strains examined. 7. The end product of beta-carboxymuconolactone metabolism by extracts was beta-oxoadipate. 8. Evidence for a coenzyme A derivative of beta-oxoadipate was found during further metabolism of this keto acid. 9. A few anomalous fungi, after growth on p-hydroxybenzoate, had no protocatechuate 3,4-oxygenase, but possessed all the enzymes of the catechol pathway. Catechol was detected in the growth medium in one instance. 10. A strain of Penicillium sp. formed pyruvate but no beta-oxoadipate from protocatechuate, suggesting the existence also of a ;meta' type of ring cleavage among fungi.
149 citations
TL;DR: In this article, a vierbein treatment is adopted in contrast to the tensorial procedure of DeWitt and Brehme, with a subsequent simplification of computations referring to the world tube.
143 citations
TL;DR: Phosphorus analyses on phospholipid fractions from membranes and whole cells showed that membranes contained proportionately more phosphatidylethanolamine and phosph atidylinositol+phosphatidylserine than whole cells, which in turn were richer in phosphatodylcholine.
Abstract: 1. Protoplasts of Saccharomyces cerevisiae N.C.Y.C. 366 were prepared by incubating washed exponential-phase cells in buffered mannitol (0·8m) containing 10mm-magnesium chloride and snail gut juice (about 8mg. of protein/ml. of reaction mixture). Protoplast membranes were obtained by bursting protoplasts in ice-cold phosphate buffer (pH7·0) containing 10mm-magnesium chloride. 2. Protoplast membranes accounted for 13–20% of the dry weight of the yeast cell. They contained on a weight basis about 39% of lipid, 49% of protein, 6% of sterol (assayed spectrophotometrically) and traces of RNA and carbohydrate (glucan+mannan). 3. The principal fatty acids in membrane lipids were C16:0, C16:1 and C18:1 acids. Whole cells contained a slightly greater proportion of C16:0 and a somewhat smaller proportion of C18:1 acids. Membrane and whole-cell lipids included monoglycerides, diglycerides, triglycerides, sterols, sterol esters, phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol+phosphatidylserine. Phosphorus analyses on phospholipid fractions from membranes and whole cells showed that membranes contained proportionately more phosphatidylethanolamine and phosphatidylinositol+phosphatidylserine than whole cells, which in turn were richer in phosphatidylcholine. Phospholipid fractions from membranes and whole cells had similar fatty acid compositions. 4. Membranes and whole cells contained two major and three minor sterol components. Gas–liquid chromatography, mass spectrometry and u.v. and i.r. spectra indicated that the major components were probably Δ5,7,22,24(28)-ergostatetraen-3β-ol and zymosterol. The minor sterol components in whole cells were probably episterol (or fecosterol), ergosterol and a C29 di-unsaturated sterol. 5. Defatted whole cells contained slightly more glutamate and ornithine and slightly less leucine and isoleucine than membranes. Otherwise, no major differences were detected in the amino acid compositions of defatted whole cells and membranes.
TL;DR: Observations provide strong additional evidence that this medullary carcinoma of the thyroid originates from the C cells.
TL;DR: Coccosteus cuspidatus is shown to be the correct name for the arthrodire commonly referred to as Cocosteus decipiens as mentioned in this paper, and an almost complete account of the osteology of this species is given and aspects of the restored head, thoracic armour, fins and posterior unarmoured region, the dermal ornamentation, neuromast system and musculature are discussed.
Abstract: Coccosteus cuspidatus is shown to be the correct name for the arthrodire commonly referred to as Coccosteus decipiens. An almost complete account of the osteology of this species is given and aspects of the restored head, thoracic armour, fins and posterior unarmoured region, the dermal ornamentation, neuromast system and musculature are discussed; the snout, dermal bones of the palate and neural endocranium receive special treatment in view of the part these structures have played in the interpretation of the relationships of the Arthrodira. Changes in the proportions of certain bones during growth are noted and the mode of life is considered. The family Coccosteidae is redefined; the genus Coccosteus and the type species C. cuspidatus are defined and consideration is given to other species included in this genus.
TL;DR: In this paper, the effect of facilitating free recall of a subset of items on recall of the remaining items of the set was investigated by giving an E Group 5 min in which to study a list of items forming the subset sets.
Abstract: Three experiments were performed to investigate the effect of facilitating free recall of a subset of items on recall of the remaining items of the set. The facilitation was induced by giving an E Group 5 min in which to study a list of items forming the subset Sets used were the States of the U.S.A. and the Counties of England. Immediately following the period of study, both groups attempted free recall of all the set. List study facilitated recall of list items but impaired recall of nonlist items.
TL;DR: The Faeroe Islands consist of almost 3,000 m of plateau basaltic lavas in which three main series have been recognized as discussed by the authors : the lower series consists of forty to fifty moderately massive flows of average thickness 20 m, separated from the thin flows of the Middle Series by about 10 m of sediment containing coal horizons of probable Eocene age.
Abstract: THE Faeroe Islands consist of almost 3,000 m of plateau basaltic lavas in which three main series have been recognized1. The Lower Series consists of forty to fifty moderately massive flows of average thickness 20 m, separated from the thin flows of the Middle Series by about 10 m of sediment containing coal horizons2 of probable Eocene age. The Middle Series occupies about 1,300 m. The Upper Series consists of well marked flows intercalated with tuffs; the flows (which average 10 m in thickness) are somewhat less massive than those of the Lower Series, and appear to have been erupted without noticeable break from those of the Middle Series. Intrusive rocks are uncommon, although some sills are very well developed within the Middle Series.
TL;DR: The main use of immunofluorescence in both human and veterinary virology should be for the rapid detection of antigen at site of lesion, and the use of conventional, egg-derived and monoclonal antibodies discussed.
TL;DR: Detailed pedigrees of the population of Tristan da Cunha have been used to give an answer to the question of how far accidental sampling errors in small populations influence their genetic make-up.
Abstract: How far do accidental sampling errors in small populations influence their genetic make-up ? Detailed pedigrees of the population of Tristan da Cunha have been used to give an answer to this question.
TL;DR: In this paper, it was shown theoretically and illustrated experimentally that an entirely diffusion-controlled adsorption process leads to a frequency-dependence of an electrode impedance which is analogous to that produced by a dielectric relaxation process with a particular spread of relaxation times.
TL;DR: In this paper, the authors improved their previous self-exciting "homogeneous" laboratory dynamo and developed a completely homogeneous dynamo that exhibits spontaneous oscillation and reversal of its magnetic field.
Abstract: WE have improved our previous self-exciting “homogeneous” laboratory dynamo1; the new dynamo is in essence completely homogeneous and exhibits spontaneous oscillation and reversal of its magnetic field.
TL;DR: In this paper, the ages of sixteen Mesozoic (Kaoko) basalts and dolerities from the Damaraland igneous province of South-West Africa are presented.
TL;DR: The ratio of monoglucosyl diglyceride to diglucosym diglycerides increased with the age of the culture, though the total glycolipid concentration remained virtually constant, and the glycolIPid concentration was unaffected by the addition of cholesterol to the culture medium.
Abstract: 1. Total lipid was extracted from Mycoplasma laidlawii strain B with chloroform–methanol mixtures and fractionated into neutral lipid, glycolipid and phospholipid components by chromatography on silicic acid. 2. Saponification of the glycolipid fraction, which represented nearly half of the total lipid, yielded two glycosides for which the structures O-α-d-glucopyranosyl-(1→1)-d-glycerol and O-α-d-glucopyranosyl-(1→2)-O-α-d-glucopyranosyl-(1→1)-d-glycerol were established. 3. The ratio of monoglucosyl diglyceride to diglucosyl diglyceride increased with the age of the culture, though the total glycolipid concentration remained virtually constant. The glycolipid concentration was unaffected by the addition of cholesterol to the culture medium. 4. The phospholipid fraction consisted of two components, phosphatidylglucose and phosphatidylglycerol. Organisms harvested at acidic pH also contained O-amino acyl esters of phosphatidylglycerol. No lipids containing inositol could be detected.
TL;DR: It is suggested that an important feature of catalase action may be a mediation of the formation of a reactive intermediate by stereospecifically located acid-base functions in the active site ofCatalase.
Abstract: 1. The mechanisms of catalase action advanced by Jones & Wynne-Jones (1962) and by Nicholls (1964) are compared in terms of their relative plausibilities and their utility for extension to accommodate more recent experimental information. 2. A revised formal mechanism is advanced that avoids the less satisfactory features of these mechanisms and attempts to account for the roles of catalase sub-units in both reversible and irreversible deactivation phenomena. 3. Theoretical studies of the redox chemistry of peroxides are used to provide the basis for a discussion of the mechanism of the redox act in catalatic action at the molecular level. It is suggested that an important feature of catalase action may be a mediation of the formation of a reactive intermediate by stereospecifically located acid–base functions in the active site. 4. A more detailed statement of this concept is attempted in terms of a hypothetical partial molecular model for the composition and stereochemistry of the active site of catalase. The utility of this model in describing the catalatic and peroxidatic actions of catalase is assessed.
TL;DR: Using interference microscopy, it is shown that the free second-stage larva of the potato-root eelworm, Heterodera rostochiensis, takes up water at the same rate as one still inside the eggshell; the enclosed larva, however, loses water far less rapidly.
Abstract: Using interference microscopy, it is shown that the free second-stage larva of the potato-root eelworm, Heterodera rostochiensis , takes up water at the same rate as one still inside the eggshell; the enclosed larva, however, loses water far less rapidly. It is considered that the shell, freely permeable to water when wet, becomes increasingly impermeable as it dries; the resulting reduction in the rate at which the enclosed larva dries, to which the cyst wall will also contribute, is thought to be of decisive importance for survival. Mechanisms of a similar kind probably operate in the fourth-stage larva of the narcissus strain of D. dipsaci , both in the ‘eelworm wool’ aggregations and in the isolated individual larva. In the aggregations, nematodes on the outside of the mass died first: they also dry sooner. There is evidence that, in the isolated larva, a decrease in the perm eability of the drying cuticle slows the drying of deeper layers of the organism.
TL;DR: In a holothurian and an ophiuroid, tritiated glucose and glycine in great dilution are removed from seawater by uptake through the skin, an indication that there are specialized cellular responses to exogenous organic molecules.
Abstract: In a holothurian and an ophiuroid, tritiated glucose and glycine in great dilution are removed from seawater by uptake through the skin. Cells differ in their competence to metabolize specific nutrients, an indication that there are specialized cellular responses to exogenous organic molecules. Embryonic ophiuroid tissues have an exceptional capacity for assimilation.
TL;DR: The surgical procedure used to introduce, in a single operation, a cannula into the rumen and re-entrant cannulae into the proximal duodenum and terminal ileum of the sheep is described.
TL;DR: It has been confirmed that certain buffer components have marked inhibitory effects on the catalatic reaction and that, in unbuffered systems,Catalatic activity is substantially independent of pH in the range 4.7-10.5.
Abstract: 1. A re-examination of the catalase-hydrogen peroxide reaction at high substrate concentrations, by using the quenched-flow technique, reveals a more complex kinetic behaviour than that previously reported. At constant reaction time the catalatic process obeys Michaelis-Menten kinetics, but the apparent Michaelis constant is markedly time-dependent, whereas the conventional catalase activity is independent of time. 2. The kinetics of the ;time effect' were analysed and it is suggested that the effect derives from the formation of an inactive species (thought to be catalase Compound II). The process shows Michaelis-Menten kinetics, with a Michaelis constant equal to that for the catalatic reaction in the limit of zero reaction time. 3. It has been confirmed that certain buffer components have marked inhibitory effects on the catalatic reaction and that, in unbuffered systems, catalatic activity is substantially independent of pH in the range 4.7-10.5.
TL;DR: The specificity of the catechol 2,3-oxygenase induced by the arylsulphonates, towards catechols and the methylcatechols, varied during the purification and suggested that 3-methylcatechol was probably oxidized by a separate enzyme.
Abstract: 1. Species of Pseudomonas capable of degrading arylsulphonates and detergents of the alkylbenzenesulphonate type were isolated from sewage and river water. 2. Benzenesulphinate, benzenesulphonate and toluene-p-sulphonate were rapidly degraded by these organisms with the release of the sulphonate group as sulphite; detergent homologues with a chain length up to 16 carbon atoms (4-n-hexadecyl-benzenesulphonate) also released sulphite. Sulphite oxidation to sulphate in the medium can occur non-enzymically. 3. Growth on benzenesulphonate and toluene-p-sulphonate elicited a catechol 2,3-oxygenase, which effected a ;meta' cleavage of the ring. The metabolic route for benzenesulphonate was determined as: benzenesulphonate-->catechol-->2-hydroxymuconic semialdehyde-->formate and 4-hydroxy-2-oxovalerate-->acetaldehyde and pyruvate; the enzymes catalysing these steps were all inducible. 4. Toluene-p-sulphonate was degraded via 2-hydroxy-5-methylmuconic semialdehyde to formate and 4-hydroxy-2-oxohexanoate and the latter was cleaved to propionaldehyde and pyruvate. Propionaldehyde and propionate were oxidized rapidly by toluene-p-sulphonate-grown cells but slowly by fumarate-grown organisms. 5. The specificity of the catechol 2,3-oxygenase induced by the arylsulphonates, towards catechol and the methylcatechols, varied during the purification and suggested that 3-methylcatechol was probably oxidized by a separate enzyme. Detergents of the alkylbenzenesulphonate type also induced a catechol 2,3-oxygenase in these bacteria. 6. A few isolates, after growth on benzenesulphonate, opened the ring of catechol by an ;ortho' route to form cis-cis-muconate. The enzymes to degrade this intermediate to beta-oxoadipate were also present in induced cells.