Showing papers by "University of Birmingham published in 1970"
TL;DR: It is suggested that the Differences in the low-molecular-weight components of myosin from different types of muscle are a consequence of differences in the isoenzyme composition of the myosins.
Abstract: 1. The low-molecular-weight components of myosin freshly prepared by the standard procedure from adult rabbit skeletal muscle migrated as four main bands Ml1, Ml2, Ml3 and Ml4 on polyacrylamide-gel electrophoresis in 8m-urea. 2. The number of bands increased on storage. This change was accelerated by increasing the temperature and pH. 3. None of the bands had electrophoretic mobilities identical with those of the well-characterized proteins of the myofibril or with the sarcoplasmic proteins. 4. By varying the ionic conditions and concentration of muscle mince used for the initial extraction it was possible to change the relative proportions of the two electrophoretic bands of intermediate mobility, Ml2 and Ml3. 5. The four-band picture similar to that obtained with rabbit was observed with myosin isolated from skeletal muscle of the rat, mouse, hamster, pigeon and chicken. 6. Rabbit cardiac myosin gave only two bands on electrophoresis. Myosin from rabbit red muscle gave a pattern intermediate between cardiac and white-skeletal-muscle myosin, i.e. the two fastest bands were present in decreased relative amounts. 7. It is suggested that the differences in the low-molecular-weight components of myosin from different types of muscle are a consequence of differences in the isoenzyme composition of the myosins.
653 citations
TL;DR: It seems that the likelihood of an individual responding to cytotoxic drugs can be predicted from his initial steroid response alone, and a favourable outcome despite resistance to conventional therapy is found.
274 citations
TL;DR: The characteristics of the indicator factor (I) which takes part in reactive hemolysis and its identification as the seventh component of complement showed that I was a late acting complement component necessary for the lysis of cells after the EAC142 stage.
Abstract: It has been shown that the "activated reactor" that is produced in certain human sera by complement activation is a stable complex of the fifth and sixth component of complement (C56). On interaction with C7, the indicator factor, a complex C567 is formed which for a short time (half-life less than 1 min) has an activated binding site and can attach itself to normal red cell membranes, conferring on them the hemolytic properties of the "heat stable" complement intermediate EC 1 ∼ 7, the capacity to be lysed by C8 and C9. These cells have neither antibody nor the complement components up to C3 bound on them.
The binding site—activated C567c—can similarly bind to other hydrophobic surfaces, including agarose gel where it forms a "stainable line".
If the complex is not bound to a surface, the binding site decays and the resulting complex will no longer give rise to lysis. However it will still inactivate C8 and C9 in solution. The sera that can generate activated reactor apparently do so because they have an excess of C5 and C6, compared to their content of C7.
The phenomenon of reactive lysis thus represents complement-mediated lysis of unsensitized cells initiated at the C5 stage by a stable complex (C56) which was generated by complement activation at a distance.
The immunochemistry of the phenomenon is described and some of its implications discussed.
241 citations
229 citations
TL;DR: In this article, a family of sum rules which relate the proton electromagnetic form factors to proton electroproduction cross sections are presented, which provide a test of the local commutation properties of the electric current operators.
210 citations
TL;DR: It has been suggested that the dermal papilla may be involved in both the induction of follicle lengthening and hair growth during the proanagen phase of the hair cycle, a concept now justified by direct experimentation in the vibrissa follicle at least.
Abstract: Hair follicles are essentially composed of two tissues. The inner epidermal component, which gives rise to, among other products, the keratinized hair shaft, is confluent with the surface epidermis and is ensheathed by the dermal component which is confluent with the pars papillaris of the dermis. A specialization of the dermal component is the dermal papilla which, in follicles producing hair, is enclosed by the epidermal matrix of the hair bulb and is connected to the dermal sheath by the papilla stalk. Many authorities have considered that the dermal papilla is an essential component of the hair follicle (reviews: Cohen, 1965; Oliver, 1969). It has been suggested that the dermal papilla may be involved in both the induction of follicle lengthening and hair growth during the proanagen phase (Chase, 1965) of the hair cycle, a concept now justified by direct experimentation in the vibrissa follicle at least (Oliver, 1967b), and perhaps also in determining the nature of the hair produced by a follicle.
201 citations
TL;DR: This paper describes how the subjective probabilities of overhaul completion gleaned from workers in each power station, are combined in the Midlands Region Information Centre, resulting in a prediction of the expected capabilities of the level of power generation over a possible horizon of 30 weeks.
193 citations
TL;DR: The agonistic behaviour of pairs of hamsters when placed for 10-15 minutes in a neutral cage was observed and body weight was positively correlated with aggressive success.
Abstract: The agonistic behaviour of pairs of hamsters when placed for 10-15 minutes in a neutral cage was observed. The first step in an encounter between two animals of the same sex is usually unilateral or mutual investigation. The aggressively dominant animal initiates investigation more frequently than his partner. Dominance is usually established by one animal winning all the interactions in any one test; in many cases this is accomplished by ritual postures during sparring, although overt fights occurred in about half the tests. Body weight was positively correlated with aggressive success. There was no sex difference in any measures of agonistic behaviour. In encounters between animals of opposite sex, the male almost invariably starts sniffing and following the female. If she is in oestrus, she responds by lordosis and active copulation follows; there is almost no agonistic interaction. On the contrary, a sexually unreceptive female often shows aggression towards the male who may respond by evasion or counter-attack. Even when matched for weight, females win most of the encounters. When their sexual advances are rebuffed by the females' offensive behaviour, males frequently engage in cage marking. Maximal agonistic behaviour as well as marking occurs at the mid-point of the cycle between consecutive oestrous periods.
177 citations
TL;DR: The phenomenon of reactive lysis represents complement-mediated lysis of unsensitized cells initiated at the C5 stage by a stable complex (C56) which was generated by complement activation at a distance.
Abstract: This paper describes the characteristics of the indicator factor (I) which takes part in reactive hemolysis and its identification as the seventh component of complement. I was shown to be a beta globulin with a sediment coefficient of 5.7S and a molecular weight of about 140,000. Experiments on the depletion of I activity with anti-I antiserum or with activated R euglobulin showed that I was a late acting complement component necessary for the lysis of cells after the EAC142 stage. Complement component analysis of purified I fractions excluded all known components except C7. The physicochemical characteristics of I are compatible with published data on C7. The method of quantitation described represents a convenient method of testing for C7.
154 citations
TL;DR: In this paper, the present-day so-called "ancestral forms," which are very closely related to cultivated plants and which in many cases seem to have evolved in a parallel way to them, are compared with each other and find a common factor: this is their "weediness", which is seen not only in the wild relatives but also in the cultivated plants themselves.
Abstract: All botanists who have given thought to problems of agricultural origins are agreed on two points: (i) that cultivated plants arose from a rather restricted number of plant families, and (ii) that plant domestication was restricted to certain parts of the globe only. There is no doubt that primitive man gathered all kinds of plants for food and other purposes wherever he went. Nevertheless, most plants have remained wild, and only an infinitesimal portion of our total plant life has ever been cultivated. Why, then, were certain plants cultivated and others not? We must suppose that the ancestors of our cultivated plants possessed some special attribute which made it possible for them to be cultivated when certain other factors came into operation. If we could actually look at these ancestral forms we could perhaps find out what this attribute was. However, in very few cases can we look back in time and actually examine archaeological remains of the ancestors of domesticated plants. Nevertheless, we can look at the present-day so-called "ancestral forms," which are very closely related to cultivated plants and which in many cases seem to have evolved in a parallel way to them. On comparing them with cultivated plants and with each other we find a common factor: this is their "weediness," which is seen not only in the wild relatives but also in the cultivated plants themselves. We should be clear here that we are not discussing the temperate and tropical tree fruits, which seem to have been domesticated in quite another way; however, probably all domesticated herbaceous plants and their wild relatives possess this "weed-
146 citations
TL;DR: The complexity of the polarization spectra confirms the presence of different types of chromophore, designated sensitizing (;s') and fluorescing (;f'), in a single protein.
Abstract: Several phycobiliproteins were prepared chromatographically pure and their absorption, fluorescence-emission, fluorescence-excitation and fluorescence-excitation polarization spectra determined. Changes in these spectra with ionic strength of the aqueous medium and chromoprotein concentration were interpreted in terms of interchromophore energy transfer and protein subunit equilibria. The complexity of the polarization spectra confirms the presence of different types of chromophore, designated sensitizing (‘s’) and fluorescing (‘f’), in a single protein.
TL;DR: Mean V.R.S. (verbal reasoning) scores recorded in the eleven‐plus examination for Birmingham multiple births in the years 1950‐57 were 95‐7 for 2164 twins and 91‐6 for 33 triplets.
Abstract: SUMMARY
Mean V.R. (verbal reasoning) scores recorded in the eleven-plus examination for Birmingham multiple births in the years 1950-57 were 95-7 for 2164 twins and 91-6 for 33 triplets. The mean for 48,913 single children born in the years 1950-54 was 100-1.
The low scores of twins are not explained by differences from single births in their distributions by maternal age and birth order or by birth weight and duration of gestation. They are also not accounted for by the increased risks associated with monozygosity (assessed by comparison of like- and unlike-sex twins) or with delivery of the second twin. Taken together these observations, like the previous ones on single births, suggest that variation in experience before and during birth has little influence on measured intelligence and that the explanation of the large difference between twins and single children must be sought in the postnatal environment.
There were 148 twins whose co-twins were stillborn or died within 4 weeks after birth; their mean score was 98-8, only a little lower than that of single births (99-5) standardized to the maternal age and birth rank distribution of twins. From this evidence it is concluded that the handicapping of twins, reflected in their low verbal reasoning scores, is due to postnatal rather than prenatal influences.
These conclusions are of course based on children who took the eleven-plus examination and cannot be accepted without reservations for those who did not.
TL;DR: The earlier conclusions which indicated that soil organic matter could reduce the phytotoxicity of s-triazines and other preemergent herbicides were drawn from the analysis of data by simple correlation analysis and by multiple regression analysis, but Bailey and White (1964) have pointed out that these and other soil properties which can be highly or significantly correlated with the lowering of herbicides can also behighly or significantly inter-correlated.
Abstract: The earlier conclusions which indicated that soil organic matter could reduce the phytotoxicity of s-triazines and other preemergent herbicides were drawn from the analysis of data by simple correlation analysis and by multiple regression analysis These techniques also indicated that the cation-exchange capacities and, in some instances, the clay contents of soils could also be inversely correlated with preemergent herbicide phytotoxicity Bailey and White (1964) have pointed out, however, that these and other soil properties which can be highly or significantly correlated with the lowering of herbicide phytotoxicity can also be highly or significantly inter-correlated
TL;DR: Genotype-environment interaction and developmental regulation in Arabidopsis thaliana II is studied to determine the role that environment plays in the development of juvenileArabidopsis.
Abstract: Genotype-environment interaction and developmental regulation in Arabidopsis thaliana II. Inbred lines; analysis
TL;DR: Treatment of rat and human erythrocyte ghosts with phospholipase C (EC 3.4.1.3) hydrolysed individualospholipids at different rates, causing significant shrinkage of the ghosts and implications regarding the molecular organisation of the membrane and the mode of action of phospholIPase C on membranes have been considered.
TL;DR: In this paper, the effects of the crystallographic direction of applied stress on the dislocation and transformation structure developed in austenitic stainless steel has been investigated and the relationships are analysed in terms of the interaction between the applied stress and the strain involved in the γ → α′ transformation.
TL;DR: In this paper, a critical discussion is given of the Kelvin method of measuring work functions and surface potentials, and the practical limits to its precision are discussed in turn: these are noise, the effects of stray capacitance, and variations in the work function of the reference surface.
Abstract: A critical discussion is given of the Kelvin method of measuring work functions and surface potentials. There is a short description of the theory and a review of the technical development of the method. The practical limits to its precision are discussed in turn: these are noise, the effects of stray capacitance, and variations in the work function of the reference surface. Suggestions are made for a new technical variation of the method, and for a new type of reference surface that should have advantages for measuring the surface potentials of gases on metals.
TL;DR: Fluorescence lifetimes and absolute quantum yields of a number of chromatographically pure phycobiliproteins have been determined using absorption, fluorescence emission and polarization spectra to calculate the number of different types of chromophore, sensitizing and fluorescing, per chromoprotein.
Abstract: — Fluorescence lifetimes and absolute quantum yields of a number of chromatographically pure phycobiliproteins have been determined. In conjunction with absorption, fluorescence emission and polarization spectra, these data were used to calculate the number of different types of chromophore, sensitizing and fluorescing, per chromoprotein.
To characterize the spatial distributions of the chromophores, the observed emission anisotropies were compared with those calculated from models, using the Forster transfer mechanism and the Jablonski ‘active sphere’ approximation. The experimental values are more consistent with surface locations for the fluorescing chromophores rather than with their distribution throughout the volume.
Theoretical efficiencies of transfer between sensitizing and fluorescing chromophores on the same macromolecule are consistent with those observed. The transfer efficiency from phycoerythrin prosthetic groups to chlorophyll a compared with that for transfer via phycocyanin indicates that the latter process is probably the favoured migration route.
TL;DR: A general method for the detection of additive, dominance and epistatic components of variation III of F 2 and backcross populations.
Abstract: A general method for the detection of additive, dominance and epistatic components of variation III. F 2 and backcross populations
TL;DR: The rapid and extensive conversion of glucose‐carbon into amino acids is an index of the final coordination of the mechanisms underlying energy metabolism in the adult brain and develops in the rat during a short period of about 19 days after birth.
Abstract: —
1
The rapid and extensive conversion of glucose-carbon into amino acids is an index of the final coordination of the mechanisms underlying energy metabolism in the adult brain. This phenomenon develops in the rat during a short period extending from 10 to about 19 days after birth. The underlying factors have been analysed.
2
The development of the pattern of distribution of glucose-carbon characteristic of the adult brain was markedly influenced by the thyroid state of the animals. The age-curve for the conversion of glucose-carbon into brain amino acids was displaced to the left after treatment with thyroid hormone (T3) in infancy thus indicating an accelerated maturation. Conversely, neonatal thyroidectomy resulted in a significant retardation in the conversion of glucose-carbon into amino acids.
3
The specific radioactivity of glutamate increased five-fold in the brain of normal rats from the 10th to the 19th day of age. The values (as a percentage of those for littermate controls) were 220 in the case of the 10 day-old thyroid treated rats and about 30 for the 19 day-old thyroid deficient animals. At the age of 10 days neither treatment affected the concentration of glutamate which was also only slightly less than the control values in the brain of 19 day-old thyroid deficient animals (–17 per cent).
4
Specific pool(s) of glutamate associated with the formation of GABA can be demonstrated in the brain of 19 day-old rats after administration of [U-14C]glucose as a result of anoxia post mortem. These pools did not develop in the brain of 10 day-old animals. Neonatal thyroidectomy retarded the development of these glutamate pools.
5
Evidence is summarized which indicates that the development of the rapid conversion of glucose-carbon into amino acids reflects the enlargement, during maturation, of the metabolic compartments which are associated with neuronal processes.
TL;DR: In this article, the Joint Epicentre Method (JEM) has been used to calculate the P-wave travel times using the joint epicentre method, which leads to a considerable improvement in the location of epicentres whose true positions are known.
Abstract: Summary
The evaluation of P-wave travel times using the Joint Epicentre Method has recently been briefly described.
Here the method, which computes epicentres and travel-time corrections simultaneously, is described in full. Results indicate that there exist regional variations in travel times not revealed fully by standard methods. Use of the new travel times leads to a considerable improvement in the location of epicentres whose true positions are known.
TL;DR: The enzyme reactions are summarized below and include phosphatidylinositol PI kinase, which was extensively studied by Michell & Hawthorne (1965) and Michell and co-workers ( 1967) and kidney TPI phosphomonoesterase was investigated by Lee and colleagues (1968).
Abstract: Our interest in the polyphosphoinositides of brain centers around the rapid turnover of their monoesterified phosphate groups (Brockerhoff & Ballou, 1962). Recentiy, enzymes that catalzye phosphorylation and dephosphorylation of the polyphosphoinositides have been studied. These are triphosphoinositide (TPI) phosphomonoesterase (Dawson & Thompson, 1964), phosphatidylinositol (PI) kinase (Colodzin & Kennedy, 1965: Kai et al., 1966b) and diphosphoinositide (DPI) kinase (Kai et al., 1968). Outside the nervous system, liver PI kinase was extensively studied by Michell & Hawthorne (1965) and Michell and co-workers ( 1967) ; kidney TPI phosphomonoesterase was investigated by Lee and colleagues (1968). The enzyme reactions are summarized below :
TL;DR: In this article, a Markov approach is used to calculate the mean cycle time and the mean time to first failure of a repairable system, and various special techniques such as lumping states or decomposing the system into independent subsystems are discussed.
Abstract: In analyzing repairable systems it is often necessary to determine such parameters as availability, mean cycle time, and mean time to first failure. These and other failure time measures are defined, and methods of calculating them using a Markov approach are developed. Although conceptually simple, these methods are often not practically feasible because of the large number of possible system states. Various special techniques such as lumping states or decomposing the system into independent subsystems are discussed. These techniques, if applicable, can simplify the analysis considerably.
TL;DR: A newly defined small lithospheric plate in the eastern Scotia Sea accounts for the intense seismicity at the South Sandwich Trench as discussed by the authors, which is the most seismically active region in the world.
Abstract: A newly defined small lithospheric plate in the eastern Scotia Sea accounts for the intense seismicity at the South Sandwich Trench.
TL;DR: In this article, a room temperature X-ray crystallographic and metallographic study has been carried out on zirconium hydrides in the composition rangec ZrH1.27 to Zr H1.92.
TL;DR: In this article, the effects of dissolved carbon and testtemperature on the development of fatigue damage in a low-carbon steel were investigated using optical and electron microscopy, and it was concluded that active slip bands are not effectively strengthened by strain ageing during continuous cycling.