Showing papers by "University of Auckland published in 1979"
TL;DR: Serum-immunoreactive-trypsin was measured in children with cystic fibrosis and a variety of controls and has potential as a screening test for C.F. in the newborn.
386 citations
TL;DR: The physical forces acting on the flexor digitorum profundus tendon of the rabbit were altered by anterior translocation of the tendon and the glycosaminoglycan (GAG) content was determined in regions of the Achilles tendon previously under tension or previously subjected to pressure.
Abstract: The physical forces acting on the flexor digitorum profundus tendon of the rabbit were altered by anterior translocation of the tendon. The glycosaminoglycan (GAG) content was determined in regions of the tendon previously under tension or previously subjected to pressure. There was an increase in the GAG content in the original tension transmitting region. Initially this was due to increased hyaluronic acid and chondroitin sulfate content during the early remodeling phase. Later when tension was restored to the translocated tendon, the content of these two GAG decreased to normal values while the high overall GAG concentration was maintained by increased amounts of dermatan sulfate. Finally the dermatan sulfate content and the total GAG content returned to normal values.The original pressure bearing region showed a rapid loss of total GAG. This was mainly due to a loss of chondroitin sulfate component, and eventually the region showed a GAG composition similar to that of normal tension transmitting tendo...
215 citations
TL;DR: The pendulum swung decisively away from maternal control towards fetal control and the fetal endocrine system became the focus of attention of most investigators.
Abstract: The discovery in 1910 (see Liggins, 1988, for historical review) of the dependence of continuing pregnancy in rodents on the corpus luteum and the subsequent isolation of progesterone seemed to provide a sound basis for the mechanism initiating parturition. The ‘progesterone withdrawal’ hypothesis gained widespread acceptance regardless of whether the maintenance of pregnancy was corpus luteum dependent or placenta dependent. Because the luteotrophic complex of hormones in rodents is of maternal origin, little reason existed to depart from the traditional view that the mechanism resided in the mother rather than the conceptus. However, the 1950s saw increasing awareness of the evidence that fetal genotype in farm animals and certain fetal malformations in both man and farm animals influence the duration of pregnancy. With the unequivocal demonstration in 1967 that hypophysectomy in fetal sheep abolishes the initiation of parturition, the pendulum swung decisively away from maternal control towards fetal control and the fetal endocrine system became the focus of attention of most investigators.
154 citations
TL;DR: It is concluded that papulacandin B and probably also echinocand in B inhibit glucan synthesis during cell-wall synthesis, and thus cause lysis of cells by osmotic rupture.
Abstract: Papulacandin B, the main component of a series of antibiotics produced by the deuteromycete Papularia sphaerosperma, inhibits the growth of yeasts. It is a highly amphophilic substance containing residues of glucose, galactose and two long-chain unsaturated fatty acids. It does not cause the release of potassium ions from yeast cells and therefore differs in its mode of action from the polyene antibiotics. Papulacandin B, at concentrations slightly below the minimal inhibitory concentration, partially but selectively inhibited the incorporation of glucose into cells of Saccharomyces cerevisiae and Candida albicans. A much clearer effect was observed on spheroplasts, obtained by digestion of the yeast cell wall with snail digestive enzyme. Incubation of spheroplasts in a minimal medium stabilised by sorbitol led to the incorporation of glucose into alkali-insoluble glucan, mannan and a fraction containing mainly alkali-soluble 1,3-glucan together with some glycogen. Papulacandin B inhibited the synthesis of the alkali-insoluble fraction, while causing a slight stimulation of glucose incorporation into the other two polysaccharide fractions. The 50% inhibitory concentrations of papulacandin B for glucan synthesis in S. cerevisiae spheroplasts and C. albicans spheroplasts were respectively 0.16 μg/ml and 0.03 μg/ml. C. albicans cells were irradiated with ultraviolet light and selected for maximum resistance to papulacandin B. The 50% inhibitory concentration for glucan synthesis in spheroplasts prepared from this mutant was 2.5 μg/ml. Echinocandin B, a polypeptide antibiotic containing a long-chain fatty acid, also inhibited the synthesis of glucan in spheroplasts. It is concluded that papulacandin B and probably also echinocandin B inhibit glucan synthesis during cell-wall synthesis, and thus cause lysis of cells by osmotic rupture.
130 citations
TL;DR: Five pigeons were trained to detect differences in light intensity using a standard signal-detection design and changes in response bias were a function of variations in the relative reinforcement ratio for the choice responses and not a function in the probability of stimulus presentation.
Abstract: Five pigeons were trained to detect differences in light intensity. Two stimuli, S1 and S2, differing in intensity, were arranged on the center key of a three-key chamber according to set probabilities. A peck on the center key turned on the two side keys. When S1 was presented on the center key, a peck on the left key was "correct" and when S2 was presented, a peck on the right key was "correct." Correct responses produced reinforcement and incorrect responses produced 3-second blackout. Detection performance was measured under three procedures. The first was a standard signal-detection design in which the probability of S1 was varied and the number of reinforcements obtained for correct responses to S1 was allowed to covary. In the second procedure, the probability of S1 was again varied but the distribution of reinforcements between the two choices was kept equal. In the third procedure, probability of S1 was held constant while the distribution of reinforcements was varied between the two choices. Changes in response bias were a function of variations in the relative reinforcement ratio for the choice responses and not a function of variations in the probability of stimulus presentation. Discriminability remained constant across the three procedures.
89 citations
TL;DR: Twelve species of barnacles were identified from the fouling community on the parts of the ‘Maui’ oil platform that were submerged during its tow from Japan in 1975 and after its arrival in New Zealand.
Abstract: Twelve species of barnacles were identified from the fouling community on the parts of the ‘Maui’ oil platform that were submerged during its tow from Japan in 1975 and after its arrival in New Zealand. The stalked barnacles Lepas anatifera L. var. (a) Darwin, L. anserifera L., Conchoderma auritum (L.), and C. virgatum (Spengler) probably settled during the tow across the tropical Pacific, and have been recorded in New Zealand waters before from ships (the Lepas spp.) and vertebrates (the Conchoderma spp.). The acorn barnacles were small, and probably settled in Japanese waters; Balanus variegatus Darwin and B. amphitrite Darwin already occur in northern New Zealand waters. The other six species—B. improvisus Darwin, B. albicostatus Pilsbry, B. reticulatus Utinomi, Megabalanus volcano (Pilsbry), M. rosa (Pilsbry), and Tetraclita squamosa japonica Pilsbry—have not been recorded from New Zealand before.
88 citations
TL;DR: Pukeko satisfy many of the criteria suggested by Brown (1974) which lead to communality and the number of birds in a group appears to relate to the costs of territorial defence which is in turn linked to habitat structure.
Abstract: 1.
The social organization and dispersal of pukeko or swamphen, Porphyrio porphyrio melanotus, was studied in two different habitats in the Manawatu, New Zealand.
2.
A non-territorial flock formed each summer in the swamp-lake habitat complex and fed in the pasture of breeding territories. Flocks had a high proportion of males and young. Most dispersed prior to the breeding season although some birds remained, set up territories, and attempted to breed. Such flocks did not form in the stream-pasture habitat complex.
3.
The remaining birds in both areas held territories for at least the breeding season with the number of individuals in a territory varying from two to six. Pairs were common in the stream-pasture habitat whereas groups predominated in the other swamp-lake habitat. The number of birds in a territory related to the length of the defended boundary and its stability. Within each group, pair with young, and flock a linear hierarchy was found with status related to age, sex and prior residence.
4.
Pukeko satisfy many of the criteria suggested by Brown (1974) which lead to communality. The number of birds in a group appears to relate to the costs of territorial defence which is in turn linked to habitat structure. Variations in the spatial organization are related to theories of a continuum of social organization regulating access to resources.
78 citations
TL;DR: Geophysical data show that the southern part of the Hauraki depression is a rift structure as discussed by the authors, which is made up of a fault angle depression, a median horst, and a graben.
Abstract: Geophysical data show that the southern part of the Hauraki Depression is a rift structure In W—E cross section it is made up of a fault angle depression, a median horst, and a graben A maximum thickness of about 3 km of Quaternary and Tertiary sediments fill the two depressions The fault angle depression and the graben are bounded at the eastern side by major normal faults which dip about 70 ± 10° to the west, namely, the recently discovered Kerepehi Fault in the centre and the Hauraki Fault which forms the eastern boundary of the depression A minor hinge fault (Firth of Thames Fault) probably runs along the western boundary Transverse faults cross the depression causing horizontal offsets of the major normal faults of up to 3 km Recent rifting of the southernmost part is indicated by active faulting and by shallow earthquake activity beneath the depression (focal depth ≤ 12 km) The chemistry of numerous hot springs implies that high temperatures (250–300°c) occur at depths of less than 5
69 citations
TL;DR: Size-frequency distributions from subtidal populations of Terebratella inconspicua consistently display prominent modes at 18 to 22 mm shell length, representing many years accumulation of non-growing adults.
Abstract: Size-frequency distributions from subtidal populations of Terebratella inconspicua (Sowerby, 1846) consistently display prominent modes at 18 to 22 mm shell length, representing many years accumulation of non-growing adults. In addition, these distributions contain seasonally variable modes made up of new recruits which are present in very high numbers towards the end of the breeding season, but are reduced to very low numbers by the end of their first year of life. Growth of recruits follows a sigmoid curve with considerable variability between individuals. Some adults survive at least 14 years. Females are 2 years old before they breed. Larvae are brooded internally by the parent and spawned in autumn and spring. The density of recruitment is positively correlated with the density of residents. Larvae commonly settle on the shells of large brachiopods; these recruits can survive to breed, but their survivorship as adults is lower than that of conspecifics attached to rock. Total mortality in the population is size (=age)-dependent; the mean life expectancy of a new recruit is 0.54 years compared with 2.57 years for a 1 year-old. Sources of mortality are considered.
68 citations
TL;DR: A remarkably widely dispersed and crystal-rich volcanic ash-fall deposit is described in this paper, which resulted from immense explosions generated in the littoral zone in New Zealand where a major rhyolitic ignimbrite flowed into the sea.
Abstract: A remarkably widely dispersed and crystal-rich volcanic ash-fall deposit is described, which resulted from immense explosions generated in the littoral zone in New Zealand where a major rhyolitic ignimbrite flowed into the sea This partially explains what happens when large pyroclastic flows enter water
68 citations
TL;DR: Hooded, conscious, male, laboratory rats were subjected to an ambient dry bulb temperature cycle between 12°C and 35°C over a period of approximately 5.5 h and using dead rats the temperature surrounding the tail was held constant.
Abstract: Summary
1. Hooded, conscious, male, laboratory rats were subjected to an ambient dry bulb temperature cycle between 12°C and 35°C over a period of approximately 5.5 h. The same procedure was followed using rats in which the temperature surrounding the tail was held constant, and using dead rats.
2. Temperature of the ambient air, and the rectum, flank skin, tail base and tail tip were measured during each ambient temperature cycle.
3. In both living and dead rats, a hysteresis loop was demonstrated for the relationship between all body temperatures measured and ambient temperature.
4. The hysteresis loops for tail temperature differed between living and dead rats in such a way as to indicate that tail temperature began to increase, as a result of an active process, at approximately 30°C, but this response ceased at a lower temperature.
5. The results on rats in which tail ambient temperature was held constant agreed with the preceeding observations.
6. Clear evidence of a counter-current heat exchange system in the vasculature of the rat's tail was not obtained.
7. It is concluded that the tail of the rat resembles an on/off controller in its mode of operation.
TL;DR: It is recommended that bilateral trephine biopsies be performed when a knowledge of the state of the bone marrow is important for clinical decision making and the performance of bilateral biopsy increased the yield of positive marrows from an estimate of 27 to 34, an increase of 26%.
TL;DR: It is shown how error estimates, as well as initial iterates for a succeeding step, can be expressed in terms of the t ransformed variables.
Abstract: Certain lmphclt Runge -Ku t t a methods are capable o f being t ransformed into a form which makes the modified Newton iterates in their implementa t ion capable o f efficient computa t ion . F o r the class o f such methods considered, the t ransformat ions are given exphcltly, and ~t is shown how error estimates, as well as initial iterates for a succeeding step, can be expressed in terms of the t ransformed variables
TL;DR: It is reported here that axon degeneration products alone are probably not the stimulus for collateral sprouting, and this has been taken as evidence for an earlier suggestion that products of nerve or axons degeneration may be a direct stimulus forateral sprouting.
Abstract: When disease or injury causes partial loss of innervation from a muscle, the remaining axons sprout and form new connections to the denervated muscle fibres. Sprouting can occur in two ways: from axon terminals (terminal sprouting) or from the intramuscular axons themselves, probably from the nodes of Ranvier (collateral sprouting). Terminal sprouting has been induced experimentally using various methods, including partial denervation, nerve conduction block and nerve transmission block. A common factor in the induction of terminal sprouting seems to be changes in the surface membrane of muscle fibres; these changes and terminal sprouting are prevented by direct stimulation of the muscle. Collateral sprouting has been induced only by partial denervation and is not prevented by direct stimulation. This has been taken as evidence for an earlier suggestion that products of nerve or axon degeneration may be a direct stimulus for collateral sprouting. We report here that axon degeneration products alone are probably not the stimulus for collateral sprouting.
TL;DR: Evidence and argument are presented suggesting that some glycoprotein is secreted by the gall bladder and incorporated into gall stones, and calls for further work upon the influence of these carbohydrate-rich macromolecules on cholesterol solubilization in mixed micelles.
Abstract: 1. The soluble glycoproteins of human bile, gall-bladder mucosa and gall stones have been extracted and hydrolysed, and the monosaccharides analysed by gas-liquid chromatography. 2. Human biliary glycoproteins contained 55–75% of carbohydrate, the major monosaccharide components being galactose, fucose and N-acetylglucosamine, accounting for 70–85% of all the monosaccharides. Mannose, glucose, N-acetylgalactosamine and N-acetylneuraminic acid (sialic acid) were also present. N-Acetylneuraminic acid was present in large amounts in the gall-bladder mucosa and bile of one ulcerated and markedly inflamed gall bladder. 3. The proportion of monosaccharides in soluble glycoproteins of mucosa and bile were not different in samples from subjects with or without gall stones. 4. Gall stones were analysed for cholesterol, calcium and bilirubin and classified as ‘cholesterol stones’ (7/10) and ‘pigment stones’ (3/10). Both cholesterol and pigment stones contain a variable amount of glycoprotein. The pattern of carbohydrate constituents was similar to that present in the gall-bladder mucosa and bile in the same subject. There was also no major difference between the pattern found in ‘cholesterol’ and ‘pigment’ stones. 5. Evidence and argument are presented suggesting that some glycoprotein is secreted by the gall bladder and incorporated into gall stones. This calls for further work upon the influence of these carbohydrate-rich macromolecules on cholesterol solubilization in mixed micelles.
TL;DR: In this article, the dimensions of each irreducible representation of each Lie group of transformations in an N-dimensional space were derived as a factored polynomial in N divided by a product of hook length factors.
Abstract: Formulae are derived expressing the dimensions of each irreducible representation of each of the classical Lie groups of transformations in an N-dimensional space as a factored polynomial in N divided by a product of hook length factors.
TL;DR: The annual reproductive cycle of the New Zealand starfish Stichaster australis (Verrill) was determined at Maori Bay on the west coast of Auckland and changes in the gonad shown by histological sections confirmed this cycle.
TL;DR: Five pigeons were trained on concurrent variable-interval schedules and the effects of reinforcements in previous sessions could be summarized by the performance in the immediately preceding session, giving a relatively simple relation between present performance and a combination of present reinforcement and prior session performance.
Abstract: Five pigeons were trained on concurrent variable-interval schedules. A series of conditions in which the ratio of reinforcement rates on two keys was progressively increased and then decreased was arranged twice. The birds were then exposed to an irregular sequence of conditions. Each condition in which reinforcement was available on both keys lasted six sessions. Performance in the first, third, and sixth sessions after a condition change was analyzed. Following a condition change, preference was biased toward the preference in the last condition, but this effect largely disappeared before the sixth session of training. The birds' preferences also appeared less sensitive to reinforcement rates in early sessions after a transition. Preference in a session was a function of both the reinforcements in that session and the reinforcements obtained in as many as four or five previous sessions. The effects of reinforcements in previous sessions could be summarized by the performance in the immediately preceding session, giving a relatively simple relation between present performance and a combination of present reinforcement and prior session performance. While such hysteresis could cause undermatching when only a small number of sessions are arranged in a condition, undermatching in a stable-state performance probably arises elsewhere.
TL;DR: Experiments with [1-(14)C]arabinose indicated that pentose was fermented by a pentose phosphate cycle plus glycolysis, with some indication of a minor phosphoketolase-type pathway, and adenosine 5'-triphosphate molar growth yields could not be calculated with any certainty.
Abstract: Metabolism and growth yields of Bacteroides ruminicola grown on d-xylose, l-arabinose, and l-rhamnose were studied. Growth yields were 62, 68, and 35.5 g (dry weight) per mol of carbohydrate fermented after correction for storage polysaccharide. Experiments with [1-(14)C]arabinose indicated that pentose was fermented by a pentose phosphate cycle plus glycolysis, with some indication of a minor phosphoketolase-type pathway. The product ratios from pentose were similar to those previously described for hexose. Rhamnose was fermented mainly to 1,2-propanediol, succinate, and acetate, although the latter was quantitatively less than expected. Estimates of adenosine 5'-triphosphate (ATP) molar growth yields could not be calculated with any certainty, as ATP generation by electron transport-linked phosphorylation cannot yet be assessed. If ATP were generated by substrate-level phosphorylation reactions alone, ATP molar growth yields for xylose, arabinose, and rhamnose would be 30, 28, and 35 g/mol. If calculations are based on an assumption that two ATP are generated by electron transport-linked phosphorylation per succinate, ATP molar growth yields become 15, 14, and 22 g/mol; if the assumption is also made that the pathway of lactaldehyde reduction is coupled to production of one ATP per 1,2-propanediol by electron transport-linked phosphorylation, the ATP molar growth yield for rhamnose fermentation becomes 14 g/mol. No preference can be expressed between these alternatives at present.
TL;DR: The growth interactions amongst the blue-green algal species Anabaena oscillarioides, Microcystis aeruginosa and the green alga, Chlorella sp.
Abstract: The growth interactions amongst the blue-green algal species Anabaena oscillarioides, Microcystis aeruginosa and the green alga, Chlorella sp. were studied both in mixed cultures and in filter cultures separated by a membrane filter in the two arms of an interaction U-tube. The role of nutrients especially phosphate upon the interaction has also been studied.
Anabaena and Microcystis both inhibited the growth of Chlorella while Microcystis also inhibited the growth of Anabaena. The inhibitory effect of Microcystis was found to be dependent on high concentrations of the initial algal inocula and independent of the initial concentration of nutrients such as inorganic phosphate, indicating that the nature of the inhibition is probably due to the production of inhibitory extracellular products by Microcystis. On the other hand, the inhibitory effect of Anabaena on Chlorella is the consequence of nutrient competition with Anabaena competing more effectively for the available phosphate.
TL;DR: This survey and regular samples in the study area provided 144 taxa, almost three times the maximum number previously recorded from a New Zealand stream, which did not follow the division into rhithron and potamon families suggested for New Zealand.
Abstract: SUMMARY. The macro-invertebrate fauna of Waitakere River and its tributaries, a northern New Zealand kauri forest stream, was surveyed in January 1974 and January and June 1975, as part of a study on stream community dynamics. This survey and regular samples in the study area provided 144 taxa, almost three times the maximum number previously recorded from a New Zealand stream. Many species were restricted in distribution to a high gradient tributary, or the low gradient mainstream. These did not follow the division into rhithron and potamon families suggested for New Zealand.
TL;DR: An epidemic of bronchopneumonia in infants and young children, with adenovirus type 21 infection, was observed in Auckland, New Zealand, in 1977, and when reviewed six to 12 months after diagnosis, six children had clinical signs and 13 had radiologic signs of residual pulmonary disease.
TL;DR: It is argued that these Californian limpets provide an example of a positive relationship between specialized modes of life and the number of co-occurring ecologically similar species and that these limpet species abundance and habitat selection from other parts of the world are confusing.
TL;DR: The 13C NMR spectra of 20 polymethoxy-and/or methylenedioxyflavonols are reported in this paper, where assignments have been made by examination of fully coupled spectra.
Abstract: The 13C NMR spectra of 20 polymethoxy- and/or methylenedioxyflavonols are reported In key cases assignments have been made by examination of fully coupled spectra
TL;DR: In this paper, a method for the description of human climates using standard mean climatic data is presented, where a simple scheme that produces a unitary measure of body-atmosphere energy exchanges in familiar terms of clothing, defined as insulation required for equilibrium.
TL;DR: It is just over 10 years since the Iirst report of the use of the hormone calcitonin in Paget's disease of bone and the introduction of diphosphonate, a chemical chelating agent represents a giant leap forward in the therapy of this distressing malady.
Abstract: It is just over 10 years since the Iirst report of the use of the hormone calcitonin in Paget's disease of bone (Bijvoet, 1968). One year later the cytotoxic antibiotic mithramycin was also shown to be of value and in 1971, English workers (Smith et al., 1971) reported the first results oftrea.tment with diphosphonate, a chemical chelating agent. a byproduct of research into the manufacture of soap. The very diversity of these agents hints at the nonspecificity of their action. Nevertheless, their introduction represents a giant leap forward in the therapy of this distressing malady which affects a significant proportion of our senior citizens.
TL;DR: The Malpighian tubules of the glow-worm Arachnocampa luminosa are divided into four morphologically distinct regions each comprised of a different cell type, and Type I cells exhibit features characteristic of transporting cells thought to have an absorptive function.
Abstract: The Malpighian tubules of the glow-worm Arachnocampa luminosa are divided into four morphologically distinct regions (Parts 1–4) each comprised of a different cell type (Types I–IV). The ultrastructure of Type II cells is indicative of a transport function. The basal cell surface is highly invaginated and at the apical surface the lumen is lined with microvilli about 80% of which contain mitochondria. Spherites contained in these cells are formed from small vesicles produced by the Golgi apparatus. They have a central uric acid core enclosed by laminations of phosphates of calcium and magnesium. Cells of Part 2 of the tubule secrete a fluid high in potassium (173 mM) and low in sodium (18 mM). The cell is 30 mV negative and the lumen 44 mV positive to the bathing solution. This is consistent with the proposal of an apical cation pump. The secretion produced by Part 2 of the tubules is modified by the Type I cells by the reabsorption of potassium (162 mM) and the addition of sodium (24 mM) to the primary excretory fluid. Type I cells are 20 mV negative and the lumen 22 mV positive with respect to the bathing medium. From ultrastructural observations, Type I cells exhibit features characteristic of transporting cells thought to have an absorptive function. The basal and apical cell surfaces are extensively folded, and mitochondria are found in bands above the basal infoldings and below the microvilli. Mitochondria do not penetrate the microvilli. On comparative grounds, the fine structure of Type I cells suggests that they reabsorb ions from the tubule lumen. Energy for these processes may come from the breakdown of lipids by microperoxisomes contained within these cells. Alternatively, the fluid produced by Part 2 of the tubule may be modified passively by diffusional processes across Type I cells.
TL;DR: In the endothelial tissues of this phylum, a new type of junction has been identified: an anastomosing septate junction, which adds weight to the idea that both of these junctional types may have the same occluding function.
TL;DR: Somatomedins, detectable by sulfation factor activity (SFA) and/or somatomedin-like receptor activity (SmLRA), were measured in the serum of 72 normal fetal lambs of varying gestational ages and in 12 fetuses before and after hypophysectomy.
Abstract: Somatomedins, detectable by sulfation factor activity (SFA) and/or somatomedin-like receptor activity (SmLRA), were measured in the serum of 72 normal fetal lambs of varying gestational ages and in 12 fetuses before and after hypophysectomy. Three hypophysectomized fetal lambs were infused with GH and/or insulin. Three intact fetal lambs were infused with glucose. Parturition was induced by infusion of synthetic ACTH into 5 fetal lambs. SmLRA and SFA were compared to a pool of adult sheep serum arbitrarily designated 1.00 U/ml. Serum SmLRA correlated significantly with gestational age (r = 0.65; P P > 0.05). Serum SmLRA and SFA were unchanged by hypophysectomy of the fetus and GH infusion but were reduced by insulin infusion. Plasma SmLRA correlated negatively with plasma insulin during glucose infusion (r = -0.67; P < 0.05). ...