Showing papers by "Trinity College, Dublin published in 1972"
TL;DR: By converting the polyglutamyl derivatives of the folates in rat liver it has been possible to evaluate their endogenous distribution by microbiological assay and it was found that the folate derivatives present in liver are almost exclusively attached to a polypeptide chain of five glutamate residues.
93 citations
TL;DR: Developing exogenous acceptors which would permit accurate determination of enzyme levels and gain some insight into the substrate specificity of the enzyme suggests that glycosylation occurs specifically at certain serine sites of the proteoglycan molecule.
90 citations
76 citations
67 citations
TL;DR: Fractionation of vitamin B12 binders in a normal human serum pool showed a distribution of 92% Transcobalamin II (TCII) and 8% TransCobalamin I (TCI) on DEAE‐cellulose chromatography, a discrepancy of 18% which could be due either to massive contamination of the DEae‐cellulinose TCII peak with TCI, or to the presence of a high molecular weight binder.
Abstract: Summary. Fractionation of vitamin B12 binders in a normal human serum pool showed a distribution of 92% Transcobalamin II (TCII) and 8% Transcobalamin I (TCI) on DEAE-cellulose chromatography. Separation of the same serum pool using gel filtration gave 74% TCII and 26% TCI. This 18% discrepancy could be due either to massive contamination of the DEAE-cellulose TCII peak with TCI, or to the presence of a high molecular weight binder which elutes with TCII on DEAE-cellulose, and with TCI on gel filtration.
Refractionation of the TCII peak showed it to be relatively uncontaminated with TCI. Removal of the low molecular weight binders with charcoal consistently gave a peak in the TCII area on DEAE, which subsequent gel filtration analysis showed to be of high molecular weight. This new binder is further distinguished from TCI by the observation that its vitamin B12 binding capacity does not increase to the same extent as TCI on fasting.
Since this binder could be demonstrated in 50 different normal sera, it is clearly not a pathological binder, and should be called Transcobalamin III (TCIII).
59 citations
TL;DR: For example, during February and March 1969 road excavations in Derryvree townland (H361390), section Co. Fermanagh, revealed a freshwater deposit of silts and fine sands between two thick and distinct till sheets which formed the drumlin this article.
Abstract: During February and March 1969 road excavations in Derryvree townland (H361390), section Co. Fermanagh, cut obliquely through a north-east to south-west trending drumlin 2 km north-east of Maguiresbridge (figure 1). The excavations revealed a freshwater deposit of silts and fine sands between two thick and distinct till sheets which formed the drumlin. The organic silts and fine sands contained a flora and fauna of full glacial aspect, which have given a $^{14}$C date of 30500$_{-1030}^{+1170}$ years B.P. (Birm. 166). The flora and fauna indicate that open tundra vegetation and a periglacial climatic regime prevailed in the area at this time.
50 citations
TL;DR: In this article, the authors listen to two humorous recordings one with and one without the dubbed laughter of a group of people and find that in the condition of group laughter Ss laughed more frequently and for longer.
Abstract: Forty Ss listened to two humorous recordings one with and one without the dubbed laughter of a group of people. In the condition of group laughter Ss laughed more frequently and for longer. They al...
44 citations
TL;DR: Crude pteroic acid, obtained by microbiological degradation of folic acid, has been purified by column chromatography on cellulose CF11, eluting with 0.1 M glycine buffer of pH 10.0 and saturated with isoamyl alcohol.
27 citations
TL;DR: A comparison is made between the results of incision and resection showing that while incision is simple and effective, transurethral resection is also a reliable method of treatment, especially in the uncomplicated adult cases, so long as the resection was confined to the ureterocele and the underlying vesical muscle left intact.
Abstract: SUMMARY
1. The endoscopic treatment of 51 ureteroceles is described. 39 were treated by transurethral resection, 11 by transurethral incision and 1 underwent a “spontaneous cure”.
2. A comparison is made between the results of incision and resection showing that while incision is simple and effective, transurethral resection is also a reliable method of treatment, especially in the uncomplicated adult cases, so long as the resection is confined to the ureterocele and the underlying vesical muscle left intact.
3. The prognosis in bilateral adult ureteroceles is good.
27 citations
TL;DR: Early external sphincterotomy for tetraplegic cases is suggested and the indications, operative technique, complications and results are described.
Abstract: Forty-two cases of external sphincterotomy are presented, and the indications, operative technique, complications and results are described. Early external sphincterotomy for tetraplegic cases is suggested.
27 citations
TL;DR: In this article, the authors considered the flow generated by a cylinder issuing from an orifice into a still fluid and showed that the cylinder generates a boundary layer whose thickness increases with increasing distance from the orifice.
Abstract: This paper deals with the flow generated by a cylinder issuing from an orifice into a still fluid. The cylinder generates a boundary layer whose thickness increases with increasing distance from the orifice. The properties of the boundary layer are considered (i) very close to the orifice and (ii) at large distances from the orifice. In the former case the boundary layer is very much thinner than the cylinder; in the latter case the reverse holds. Asymptotic series solution are developed in both cases. The results of (ii) are compared with the experimental evidence due to Koldenhof.
TL;DR: Only in the more severe cases with superimposed arterial occlusion did Wallerian degeneration appear, and segmental demyelination seems the fundamental nerve abnormality in rheumatoid arthritis.
Abstract: Sural nerve histopathological examination in nine rheumatoid patients revealed varying nerve and arterial changes, which were absent in the two osteoarthritic and seven road-accident necropsy controls.
Segmental demyelination without arterial change was found in four of the uncomplicated milder cases. Segmental demyelination with arterial intimal proliferation were the major findings in the two cases of the intermediate group. Wallerian degeneration with varying arterial findings were present in the three patients of the most severe group, two of whom had clinical neuropathy and arteriopathy.
Segmental demyelination seems the fundamental nerve abnormality in rheumatoid arthritis. Only in the more severe cases with superimposed arterial occlusion did Wallerian degeneration appear.
TL;DR: In this article, the magnetic recording heads made from nonlinear magnetic materials were used to calculate the magnetic fields for magnetic recording head made from ferrite magnetization curves and showed that as the head drive fields are increased, the resolution of the head deteriorates.
Abstract: Numerical methods are used to calculate the fields for magnetic recording heads made from nonlinear magnetic materials. The nonlinear model used in the study fits ferrite magnetization curves well and requires little computer time for evaluation. Results show that as the head drive fields are increased, the resolution of the head deteriorates.
TL;DR: The phenomenon of increased labeling of triglyceride in infected chick cells under certain conditions is discussed, in conjunction with the other effects, in terms of related changes in other virus-infected systems.
Abstract: Lipid metabolism in the “abortive” system, Sendai virus-infected primary chick embryo fibroblasts, was examined by using 32 P-orthophosphate, 14 C-glucose, and 14 C-glycerol as precursors. Incorporation of radioactivity from 32 P-orthophosphate and 14 C-glucose into lipid was increased in infected cells. Synthesis of all individual phospholipids was about equally stimulated. There was also evidence for increased lipid synthesis in more productively infected monkey kidney cells. Incorporation of 14 C-glycerol when at a high level in the medium was also increased. However, when this precursor was supplied in minute quantities of high specific activity, incorporation was inhibited. Even though incorporation of radioactivity from 14 C-glucose was stimulated during long labeling periods, the uptake of this precursor during short pulses was inhibited in infected cells. The phenomenon of increased labeling of triglyceride in infected chick cells under certain conditions is discussed, in conjunction with the other effects, in terms of related changes in other virus-infected systems.
TL;DR: A general method, based on the King-Altman scheme, for the derivation of the complete steady-state rate equation for an enzyme-catalysed reaction is illustrated, which appears to be less liable to errors than other methods.
TL;DR: In this article, it was suggested that the '3-hydroxy-9-methoxypterocarpan' isolated from Andira inermis was a similar mixture.
TL;DR: The importance of coronoid as well as condylar lesions in the diagnosis of limited mouth opening is emphasised and the diagnosis, intra-oral operative treatment and histology is outlined and discussed.
TL;DR: The annual variation in the mitotic index of the testis of Arenicola marina after 48 hr treatment with colchicine has been determined and the meanMitotic index remains high until September when it decreases temporarily.
Abstract: The annual variation in the mitotic index of the testis of Arenicola marina after 48 hr treatment with colchicine has been determined. This mitotic index in the population is distributed log-normally. The mean mitotic index is low in winter but increases during the spring to a maximum in early summer. The mean mitotic index remains high until September when it decreases temporarily. There is a second minor increase in the mean mitotic index prior to spawning.
Decerebration of animals prior to the spring increase in the mitotic index did not prevent this increase occurring in decerebrate animals maintained in the laboratory. Removal of the coelomic gametes was effective in stimulating the testicular mitotic index only when performed during the period of low mitotic activity in early autumn.
TL;DR: It is postulated that the obliquity of the outer smooth muscle layer of the urethra is controlled by the anterior longitudinal component of the sphincter.
Abstract: Top of pageAbstract
An anatomical study of the external sphincter of the urethra is presented. Around the membranous urethra the fibres are arranged circularly, giving off a constant anterior longitudinal prolongation into the prostatic urethra. It is postulated that the obliquity of the outer smooth muscle layer of the urethra is controlled by the anterior longitudinal component of the sphincter. An anterolateral sphincterotomy is suggested as the best method of external sphincterotomy.
01 Sep 1972
TL;DR: The rate of accumulation of mitoses in the testis of Arenicola marina has been estimated by the colchicine method and a second temporary and minor rise was observed in October or November prior to spawning.
Abstract: The rate of accumulation of mitoses in the testis of Arenicola marina has been estimated by the colchicine method. The rate is low in February but increases during spring to a maximum in June. The rate remains high during July and August but decreases in September. A second temporary and minor rise was observed in October or November prior to spawning.
The rate of accumulation of mitoses (with respect to the duration of metaphase arrest) is logarithmic from February to June, but is arithmetic during the latter part of the reproductive cycle (July-October). The transition from one phase to the next coincides with the initiation of spermatocyte release from the testis into the coelom.
The rate of accumulation of mitoses has also been recorded in testes cultured in vitro. The rate in vitro does not differ from that in vivo in May when the rate is high, but in September when the rate in vivo is depressed, culture in vitro significantly increases the mitotic rate.
The cell cycle time of the proliferating spermatogonia has been estimated by a modified per cent labelled mitosis technique. The cell cycle time is unusually long (in excess of 20 days) and the G2 period is at least 5 days. It is suggested that the testis of A. marina is an exponentially growing cell population from February until early June when coelomic spermatocytes first appear. The rate of cell release then temporarily exceeds the rate of renewal: eventually they become equal and the testis remains in steady state until September when the mitotic rate is depressed due to the presence of maturing spermatocytes. The depression of the mitotic rate in September is achieved by the arrest of spermatogonia in G2. Explanting the gonads in organ culture removes the inhibition and causes an increased flow of cells from G2 into mitosis.
TL;DR: A new method is described that uses three commercially available enzymes for the estimation of the specific activity of glucose that is specific, reproducible, and simple, involves only one critical addition, and gives over 98% recoveries in aqueous solutions and plasma.
TL;DR: This paper shows how to initialize Jewell's algorithm without difficulty, modify Jewell’s algorithm to ensure its finite convergence, and interpret Jewells algorithm as an out-of-kilter algorithm.
Abstract: Consider a capacitated network in which the flow leaving an arc equals the flow entering that arc multiplied by a constant Jewell has presented an algorithm to construct a minimal cost flow for th
TL;DR: In this article, it was shown that the periodic solutions of Li′enard equations with delay have a nontrivial periodic solution, with period greater than 2r if the following conditions hold: f(x) = −a + f1(x), f(0) = 0, and monotonically as x → +∞ (−∞).
Abstract: Publisher Summary This chapter reviews some theoretical and numerical result that the periodic solutions of Li′enard equations with delay. The equation (L) has a nontrivial periodic solution, with period greater than 2r if the following conditions hold: f(x) = −a + f1(x) is continuous for all x, f1(0) = 0, and monotonically as x → +∞ (−∞). In the proof of the theorem, geometry in the Banach space C = C([;−r, 0], R2) is used. It is shown that there is an Eigen function with eigenvalue equal to unity, and this corresponds to a periodic solution. As the trajectory takes time greater than 2r to get back to K, the period of the periodic solution is greater than 2r. In proving the theorem, it was convenient to introduce the phase plane representation. The author has used numerical computations as experiments to indicate possible answers to these questions. In the computations, a difference analog to the differential equation is solved to produce a sequence (N, xN, yN), where N= 1, 2, 3,… If the numbers (xN, yN) appear to repeat in a periodic manner, one would say the computed solution has a numerical cycle.
TL;DR: ATP-DEPENDENT deoxyribonucleases with an exonucleolytic action on native DNA have been reported from several bacterial sources, but evidence as to the role of ATP in their action is scanty, although ATP is required for the formation of a complex between the enzyme and DNA.
Abstract: ATP-DEPENDENT deoxyribonucleases with an exonucleolytic action on native DNA have been reported from several bacterial sources1. On the basis of evidence from two of these organisms, these enzymes are thought to have a role in recombination. ATP is converted to ADP and orthophosphate in the course of these enzymes' action, so that they are also DNA-dependent adenosine triphosphatases. In view of their recombination function, however, their biological role is presumably as deoxyribonucleases. Evidence as to the role of ATP in their action is scanty, although ATP is required for the formation of a complex between the enzyme and DNA2. This is, however, only a small part of the answer, since one or more ATP molecules are hydrolysed per deoxyribose solubilized1,3,4.
TL;DR: This model permits stable populations for the two species only in the region of the N1N2 plane above the line L joining the single-species equilibria, in contrast to some of the data which indicate stable populations below this line.
Abstract: CONSTRUCTION of simple models for systems in which species compete for limited resources has been aided recently by Ayala's1-3 series of experiments with Drosophila. The main conclusion of these experiments is that the competition is not explained by the simple Volterra-Gause-Witt4,5 equations illustration and illustration where rt is the innate rate of increase of species i, Ni is the number of the species at a given time, Ki is the saturation level of the species when only one species is present, βi, is the coefficient of competition and the subscripts i have the values 1 or 2. This model permits stable populations for the two species only in the region of the N1N2 plane above the line L joining the single-species equilibria, in contrast to some of the data which indicate stable populations below this line.
Open image in new window
Open image in new window
TL;DR: The mode of action of the melanin-dispersing hormone (MDH) in the shore crab Carcinus maenas was studied and the concept that the action of MDH on the melanophore may be mediated by cyclic AMP was discussed.
TL;DR: A large variety of techniques are employed at present for the assessment of peripheral arterial insufficiency in both laboratory and clinical studies, and most of them suffer from serious disadvantages.
Abstract: Reprint requests to Sir Patrick Dun’s Hospital, Dublin 2. (Mr. J. C. Milliken) * Research Assistant in Vascular Surgery, Sir Patrick Dun’s Hospital, Dublin Ireland. † Consultant Vascular Surgeon, Federated Dublin Voluntary Hospitals, Lecturer in Vascular Surgery, Trinity College, Dublin. A large variety of techniques are employed at present for the assessment of peripheral arterial insufficiency in both laboratory and clinical studies. Most of them suffer from serious disadvantages. Arteriography, which has an essential role in the determination of the patency or otherwise of major vessels in occlusive disease, gives no information on peripheral flow and is of limited value