Showing papers by "University of Hawaii at Manoa published in 1981"
Journal Article•
TL;DR: Results indicate that the fragile site is expressed because of depletion of deoxythymidine monophosphate (dTMP) available for DNA synthesis.
Abstract: Experiments designed to illuminate the mechanism by which folic acid and thymidine inhibit expression of the Xq28 fragile site in human lymphocytes are described. The fragile site is induced by 5-fluorodeoxyuridine (FUdR), a potent inhibitor of thymidylate synthetase, in the presence of otherwise inhibiting concentrations of folic acid but not in the presence of thymidine. These results indicate that the fragile site is expressed because of depletion of deoxythymidine monophosphate (dTMP) available for DNA synthesis.
208 citations
01 Sep 1981
TL;DR: In this paper, the upper water column at 17 stations occupied in the Weddell Sea in February and March 1977 was studied and the most conspicuous feature is the marked contrast between the low standing crop and primary productivity of the northern and central regions, compared with the much more productive shelf waters at the head of the Sea.
Abstract: Chlorophyll a, phaepoigments, primary production, nannoplankton, inorganic nutrients, and physical measurements were made in the upper water column at 17 stations occupied in the Weddell Sea in February and March 1977. The most conspicuous feature is the marked contrast between the low standing crop and primary productivity of the northern and central regions, compared with the much more productive shelf waters at the head of the Weddell Sea. Chlorophyll a in the euphotic zone was 4.36 ± 1.75 mg m−2 for the former regions and 31.6 ± 9.5 mg m−2 for the southern stations. Production in the water columns of the southern stations (0.41 ± 0.23 g C m−2 day−1) was approximately four times that at the northern-central ones (0.104 ± 0.092 g C m−2 day−1). Based on plant carbon: chlorophyll a ratio of 30 ± 10 estimated in the present study, an average specific growth rate (μ) of 0.71 was calculated. The nutrient concentrations showed an inverse distribution compared with those of chlorophyll a and primary production; higher nutrient concentrations were recorded at the northern stations than at the southern waters. Phosphate: nitrate: silicate ratios in the water column suggested the importance of nitrate for phytoplankton production.
A significant relationship (P < 0.001) between chlorophyll a concentration and day-zooplankton biomass and a significantly higher ratio (P < 0.06) of night-to-day catch of zooplankton in the northern-central regions than in the southern region were found. This suggests that zooplankton do not need to migrate vertically in the southern regions due to abundance of food supply, whereas in the northern-central regions zooplankton must migrate upwards during the night to consume available food produced through the photosynthetic process. The study demonstrates that water column stability, grazing, and proximity to land masses are the most significant factors controlling phytoplankton production in the Weddell Sea.
199 citations
TL;DR: It is suggested that lysophospholipids are intricately involved in the sperm acrosome reaction and perhaps in sperm-egg fusion.
Abstract: The effects of lipids on the survival, acrosome reaction, and fertilizing capacity of guinea pig spermatozoa were studied by incubating the spermatozoa in media containing various concentrations of the lipids. Lipids tested were: phosphatidyl-choline (PC), -ethanolamine (PE), -inositol (PI), -serine (PS), sphingomyelin (S), cholesterol (C), lysophosphatidyl-choline (LC), -ethanolamine (LE), -inositol (LI), -serine (LS), and glyceryl monooleate (M).
When spermatozoa were incubated in a regular medium (containing 2 mM Ca2+) with M, the majority underwent the acrosome reaction within 1 hour. None of the other lipids were as effective as M, and some were totally ineffective under the same conditions. However, when spermatozoa were preincubated in Ca2+-free medium containing LC, LE, or LI, they gained the ability to undergo the acrosome reaction. One hour of preincubation in Ca2+-free medium with LC, LE, or LI was enough to render the vast majority of spermatozoa capable of undergoing the acrosome reaction in response to Ca2+. The optimum concentrations for LC, LE, and LI were approximately 85 μg/ml, 210 μg/ml, and 140 μg/ml, respectively. Spermatozoa that had undergone the acrosome reaction by pretreatment with LC, LE, or LI remained actively motile and were capable of fertilizing eggs. LS was totally ineffective in rendering the spermatozoa capable of undergoing the acrosome reaction, and in fact it inhibited the acrosome reaction by itself and also inhibited the LC-, LE-, or LI-mediated acrosome reaction. LS did not prevent acrosome-reacted spermatozoa from penetrating the zona pellucida, but did prevent sperm-egg fusion.
Based on these findings, it is suggested that lysophospholipids are intricately involved in the sperm acrosome reaction and perhaps in sperm-egg fusion.
190 citations
164 citations
TL;DR: Analysis of data on schizophrenia concluded in favor of significant cultural inheritance, assortative mating and familial environment unique to twins, in addition to biological inheritance.
Abstract: Methods are developed for the resolution of cultural and biological inheritance based on qualitative data on pairs of relatives. Analysis of data on schizophrenia concluded in favor of significant cultural inheritance, assortative mating and familial environment unique to twins, in addition to biological inheritance. Genetic and cultural heritabilities were estimated as 0.707 ± 0.077 and 0.203 ± 0.120, respectively. Familial environmental component unique to twins was estimated as 0.090 ± 0.040.
126 citations
TL;DR: All common phenylthiohydantoin amino acids derived from sequencing are identifiable in 6 to 9 min with an isocratic method based on buffered aqueous acetonitrile, an ODS stationary phase, and programmed flow which increases during the run.
109 citations
TL;DR: Alzheimer's disease (AD) occurred in 37 individuals from two kindreds of Jewish ancestry with a mode of transmission suggesting an autosomal dominant genetic trait and genetic differences between the familial and the sporadic form of AD are discussed.
107 citations
TL;DR: The constraints on the design of twowire repeaterless digital subscriber loop (DSL) systems are explored, related to compatibility with other systems sharing the same cable, and immunity to central office noise.
Abstract: This paper explores the constraints on the design of twowire repeaterless digital subscriber loop (DSL) systems. Broadly categorized, the design depends on the technical feasibility of the approach used to achieve two-wire transmission, constraints related to compatibility with other systems sharing the same cable, and immunity to central office noise. Each of these varies With the choice of system parameters including the transmission rate, transmit power, choice of line codes, etc. Technical feasibility is evaluated by computer simulation studies. Compatibility with other systems is explored by crosstalk calculations. Noise immunity considerations, as they translate into digital line power levels, are also explored.
93 citations
TL;DR: A quiet revolution has been taking place in the way social work develops and uses knowledge for practice as mentioned in this paper, and the profession has gradually moved away from vague and haphazard formulations and toward scientifically or empirically based practice.
Abstract: A quiet revolution has been taking place in the way social work de velops and uses knowledge for practice. The profession has gradually moved away from vague and haphazard formulations and toward scientifically or empiri cally based practice. The author reviews the evidence of this change, noting that new forms of knowledge with the potential to enhance every practitioner's effec tiveness are already available, and discusses the prospects for the rev olution's success.
89 citations
TL;DR: It has been suggested that equity theory, a social psychological theory concerned with the fairness in casual relationships, should be applicable to inti mate relations as well as discussed by the authors, as a first step in...
Abstract: It has been suggested that equity theory, a social psychological theory concerned with the fairness in casual relationships, should be applicable to inti mate relations as well. As a first step in ...
77 citations
TL;DR: In this paper, the problem of steady film condensation outside a wedge or a cone embedded in a porous medium filled with a dry saturated vapor is investigated, where the condensate and the vapor are separated by a distinct boundary with no two-phase zone in between.
TL;DR: It is concluded that some of these test systems are effective tools for the detection of DNA-damaging and potentially carcinogenic compounds, especially if the assay is done in liquid suspension and if more than 1 pair of tester strains is used.
Abstract: The detection of DNA-damaging agents by repair-deficient bacterial assays is based on the differential inhibition of growth of repair-proficient and repair-deficient bacterial pairs. The various methodologies used are described and recommendations are made for their improved use. In a survey of the literature through April 1979, 91 of 276 papers evaluated contained usable data, resulting in an analysis of 611 compounds that had been assayed in 1 or more of 55 pairs of repair-proficient and repair-deficient strains. The results indicate that (1) a liquid suspension assay is more sensitive than a spot (diffusion) test. In a review of the Escherichia coli polA assay, 45 compounds that gave "No Test" in the spot test were clearly positive or negative in the liquid suspension assay. (2) Of the 21 compounds analyzed by the E. coli polA assay and by other E. coli repair-deficient strains (e.g., rec, uvr, hcr, and exr derivatives of WP2 and AB1157), 10 were in complete agreement in all strains except uvrA strains. This indicates that strains other than polA+/polA- are useful for detecting DNA-damaging agents. However, in selecting strains for use in these assays, care should be taken to consider repair pathway specificity for particular compounds. (3) There was a 78% correspondence between results obtained with E. coli polA and Bacillus subtilis (H17/M45, 17A/45T) rec assay and between E. coli polA and Proteus mirabilis. (4) In a comparison of test results with carcinogenicity data, 44 of 71 (62%) carcinogenic compounds assayed by the polA system were positive, 10 (14%) were negative, and 17 (24%) gave No Test or doubtful results. 7 carcinogens were assayed by other E. coli strains and all were positive. 56 carcinogens were assayed in B. subtilis: 24 (43%) were positive, 9 (16%) were negative, and 23 (41%) gave No Test or doubtful results. Of the 7 carcinogens assayed in P. mirabilis, 6 (86%) were positive and 1 (14%) was negative. (5) The results were analyzed with respect to chemical classes. E. coli polA detected the highest percentage of hydroxylamines and alkyl epoxides. The B. subtilis rec assay detected the highest percentage of nitrosamines and sulfur and nitrogen oxides. It is concluded that some of these test systems are effective tools for the detection of DNA-damaging and potentially carcinogenic compounds, especially if the assay is done in liquid suspension and if more than 1 pair of tester strains is used. Advantages and disadvantages of the assay are discussed and suggestions are made for improvements in the system.
TL;DR: In this paper, the structures of three sesterterpenoid antibiotics 2, 3, and 4, isolated from a marine sponge, were determined by spectral analysis and chemical transformations.
TL;DR: Foraminifera are known to obtain nutrients in a variety of ways: they are omnivores, carnivores or herbivores as discussed by the authors, and some species use the extracellular metabolites of their photosynthetic endosymbionts.
Abstract: Foraminifera are known to obtain nutrients in a variety of ways: they are omnivores, carnivores or herbivores1–3 and some species are known to use the extracellular metabolites of their photosynthetic endosymbionts1,2,4. None, however, has previously been proven to utilize exogenous dissolved organic carbon directly, although this is well known in other marine species5,6. Knowledge of foraminiferal trophic positions is important because foraminifera are common in most marine communities1 and may be the most abundant eukaryotic organism in the extensive deep-sea benthos7–9. Our studies of benthic foraminifera from an unusual Antarctic shallow water embayment now show that certain species utilize both particulate and dissolved organic material in their nutrition.
TL;DR: Hamster spermatozoa that had previously undergone motility activation in vivo or in vitro maintained vigorous behavior upon zona attachment and continued to propagate flagellar waves of large amplitude and curvature, although these waves were much more symmetrical than when prior to zzon attachment.
Abstract: Movement characteristics of hamster and guinea pig spermatozoa were studied by high-speed cinemicrography before and after initial binding to the zona pellucida. Hamster spermatozoa that had previously undergone motility activation in vivo or in vitro maintained vigorous behavior upon zona attachment. They continued to propagate flagellar waves of large amplitude and curvature, although these waves were much more symmetrical than when prior to zona attachment. The hamster sperm activated in vitro appeared slightly stimulated upon zona attachment. Such spermatozoa also bound to the zonae pellucidae of mouse eggs, and they exhibited similar movements. Preactivated hamster spermatozoa, fresh from the epididymis, did attach to the hamster zona, but exhibited relatively weak flagellar beats of low amplitude and frequency. Guinea pig spermatozoa, activated in vitro, also continued such movement and appeared somewhat stimulated upon attachment to the zona pellucida of their species.
TL;DR: It is concluded that the techniques of direct and defect dye delineation accurately define the anatomic perfusion bed of an occluded coronary artery that corresponds to the region of myocardium undergoing acute ischemic injury and hence the region at risk to infarction immediately after coronary occlusion in the three species studied.
Abstract: To assess selectively the effectiveness of therapeutic interventions to reduce infarct size, it is important to assess both ultimate infarct size as well as the size of the region of myocardium at risk to infarction. The anatomically defined perfusion bed of an occluded artery has generally been assumed to be synonymous with the region at risk of infarction. This assumption was tested by delineating the anatomic perfusion bed of an occluded artery with microvascular dyes and by examining the relation of the anatomic perfusion bed to the region of acute ischemic injury. In 8 baboons, 12 pigs and 15 dogs a major branch of the left anterior descending or left circumflex coronary artery was occluded. At 2 and 30 minutes after occlusion the eplcardial area of ischemic injury was determined by epicardial S-T segment mapping. The boundary of epicardial S-T segment elevation was resolved to within 1 mm and marked directly on the ventricular surface. The heart was then excised and the perfusion bed of the occluded artery was delineated by either (1) injecting different colored silicone rubber microvascular dyes into the previously occluded artery as well as the adjacent perfusion beds (direct method), or (2) injecting dye only into the adjacent perfusion beds (defect method). Serial cross-sections of the left ventricle from the direct and defect dye-perfused hearts in all three species showed the perfusion bed of the occluded artery to be readily demarcated. Microscopic examination demonstrated no evidence of capillary anastomoses and minimal inter-digitation of capillaries at the perfusion bed boundaries. In dye-perfused hearts, the baboon and the pig showed no evidence of precapillary anastomoses between perfusion beds; however, the dog demonstrated numerous epicardial collateral channels. The epicardial area of the anatomic perfusion bed correlated closely with the epicardial area of S-T segment elevation at 2 minutes after occlusion in the baboon (r = 0.97), pig (r = 0.99) and dog (r = 0.96). The epicardial area of S-T segment elevation did not change through the 30 minute period of occlusion in the baboon and the pig, but in the dog it showed a progressive and variable reduction reflecting the gradual recruitment of existing collateral channels from adjacent perfusion beds. It is concluded that the techniques of direct and defect dye delineation accurately define the anatomic perfusion bed of an occluded coronary artery. This anatomic perfusion bed corresponds to the region of myocardium undergoing acute ischemic injury and hence the region at risk to infarction immediately after coronary occlusion in the three species studied.
TL;DR: In this article, the importance of thermal dispersion on non-Darcian convective flow in a saturated porous medium is discussed and a new theoretical model taking into consideration thermal convective effects is proposed.
TL;DR: The general single copy DNA sequence divergence appears to be very much greater than the minimal coding region sequence divergence previously estimated from allozyme studies.
Abstract: Comparisons of the sequence divergence of three species of Hawaiian Drosophila have been made by hybridization of single-copy tracer DNA of each of the species with driver DNA from each species, and measurement of the average melting temperature (Tma) in a chaotropic solvent (2.4 M tetraethylammonium chloride) which minimizes differences due to base composition. Correction was made for the length of hybrid duplex regions to obtain the reduction in thermal stability due to divergence.
An accuracy of ± 0.2°C was achieved and the mean reduction in Tm for hybridization betweenD. heteroneura andD. silvestris (found only on the island of Hawaii) was 0.55°C and betweenD. picticornis, found only on the island of Kauai, and the other two species was 2.13°C. The rate of DNA change is estimated to be between 0.2 and 0.4%/My by assuming that theD. heteroneura-D. silvestris divergence occurred 0.8 My ago and the divergence between these species andD. picticornis between 4 and 6 My ago.
The general single copy DNA sequence divergence appears to be very much greater than the minimal coding region sequence divergence previously estimated from allozyme studies.
Journal Article•
TL;DR: To provide sufficient numbers of patients varying in age of initial adequate surgical alignment for congenital esotropia, 162 patients managed by seven ophthalmologists in three countries were personally examined by the author and the results compiled for a clinical study.
Abstract: To provide sufficient numbers of patients varying in age of initial adequate surgical alignment for congenital esotropia, 162 patients managed by seven ophthalmologists in three countries were personally examined by the author and the results compiled for a clinical study. From this population group, 106 patients were chosen who had reliable answers, satisfactory alignment, and an ophthalmologist's confirmation examination of the congenital nature of the problem by at least 1 year of age. The results of sensory testing showed that those adequately aligned by the age of 6 months vs 12 months vs 24 months were not statistically different, but those patients aligned after 24 months of age demonstrated a significantly lower percentage with evidence for binocularity (P less than 0.001). Surgical alignment in the congenital esotropic patient should be accomplished by 2 years of age to attain the highest yield of binocular function.
TL;DR: The etiology is unknown, although clinical, epidemiologic, and immunologic features suggest an acute infectious trigger to an immunologically mediated, generalized vasculitis.
Abstract: Kawasaki syndrome is a newly described, acute symptom complex of children that has a predictable clinical course. The acute febrile phase of the syndrome is characterized by multisystem acute inflammatory changes. The subacute phase follows with the rheumatic manifestations of arthritis, myocarditis, and thrombocytosis. The syndrome is self-limited in most children but is associated with coronary artery aneurysms in 15%--20% and sudden death due to coronary thrombosis in 2%. Vasculitis of coronary and other medium-sized muscular arteries characterizes fatal cases. The peak age affected is 12 months (range, six weeks to eight years). Japanese children are overrepresented among cases, whereas Caucasian children are underrepresented. Cases have been reported worldwide with the highest prevalence in Japan and among Japanese in Hawaii. Epidemic outbreaks have occurred in scattered areas of the United States and Japan. The etiology is unknown, although clinical, epidemiologic, and immunologic features suggest an acute infectious trigger to an immunologically mediated, generalized vasculitis.
TL;DR: In this paper, an electroweak gauge model is discussed, where generations are associated with separate gauge groups with different couplings, and the observed universality is the result of a mass-scale inequality.
Abstract: An electroweak gauge model is discussed, where generations are associated with separate gauge groups with different couplings. The observed ..mu..-e universality is the result of a mass-scale inequality, ..nu../sub 03/ M/sub W/ and M/sub Z//sub i/>M/sub Z/.
TL;DR: The results demonstrated the effectiveness of coronary venous retroperfusion in preserving ischemic myocardium such that anterograde reperfusion resulted in a mean reduction of 84 percent in ultimate infarct size.
Abstract: The effectiveness of selective synchronized pulsatile coronary venous retroperfusion for the temporary metabolic support of a region of acutely ischemic myocardium has previously been demonstrated. This study was designed to determine the degree of reduction in ultimate infarct size that may be achieved when coronary venous retroperfusion initiated early after coronary occlusion is combined with later anterograde reperfusion. In 10 baboons, the proximal left anterior descending coronary artery was occluded for 4 hours at which time anterograde reperfusion was restored. In five baboons (Group A), coronary venous retroperfusion was initiated 15 minutes after occlusion. Five baboons (Group B) underwent an identical procedure without coronary venous retroperfusion. Epicardial electrograms were recorded from 24 sites overlying the ischemic region. At 24 hours, hearts were excised and serial transverse sections of the left ventricle were stained with nitroblue tetrazolium for stereometric determination of infarct size. In Group A 12 ± 5.4 percent (mean ± standard error of the mean) of epicardial sites with S-T segment elevation at 15 minutes after occlusion showed subsequent Q waves, compared with 96 ± 2.3 percent in Group B (p
TL;DR: In this paper, high-amplitude, anrrow band noise that correlates with periods of high ocean bottom currents and the tidal cycle is occasionally observed on ocean bottom seismometers (OBS).
Abstract: High-amplitude, anrrow band noise that correlates with periods of high ocean bottom currents and the tidal cycle is occasionally observed on ocean bottom seismometers (OBS). The geophones on OBSs of different configurations are not equally sensitive to this noise and hydrophones are almost unaffected. With a suitable design, it should be possible to eliminate this noise problem.
TL;DR: CP-20,961 (N,N-dioctadecyl-N′,N′-bis (2-hydroxyethyl)-propanediamine), a synthetic lipoidal amine originally characterized as an interferon inducer17–20, with strong adjuvant activity for humoral and cellular immune responses is reported.
Abstract: Research towards the development of a vaccine against malaria has recently accelerated1, mainly because of a resurgence in the worldwide incidence of the disease2. These investigations have been aided by the use of the owl monkey for direct experimentation with human malaria3–5, techniques for producing Plasmodium falciparum antigen through continuous or shortterm in-vitro cultivation6,7, and the recent demonstration of effective immunization of owl monkeys against P. falciparum 8,9. However, the inclusion of a strong adjuvant in the vaccines seems to be required for the development of protective immunity. Thus, inclusion of the whole mycobacterial cell wall/mineral oil adjuvant (Freund's complete adjuvant: FCA)8,9 or a semi-synthetic derivative of the active component of that cell wall (6-O-stearoyl-N-acetylmuramyl-L-alanyl-D-iso-glutamine: stearoyl-MDP)10,11 has been necessary for the successful immunization of primates against P. falciparum. The use of X-ray irradiated parasites12–14 or substitution of FCA by muramyl-dipeptide15,16 does not result in significant protective immunity. Because the systemic and local toxic responses to the active adjuvants is either unacceptable (as in the case of FCA)10,11, or essentially undescribed (as for stearoyl-MDP), it seemed highly desirable to attempt to identify alternative, well tolerated synthetic compounds with strong adjuvant activity for malarial vaccines. A potential candidate for this role was CP-20,961 (N,N-dioctadecyl-N′,N′-bis (2-hydroxyethyl)-propanediamine), a synthetic lipoidal amine, originally characterized as an interferon inducer17–20, with strong adjuvant activity for humoral and cellular immune responses21,22. We now report that killed P. falciparum merozoite antigen administered with CP-20,961 can effectively immunize owl monkeys against a lethal P. falciparum infection.
TL;DR: It is demonstrated that in island populations, separated one from the other both by distance and by cultural attributes, schizophrenia is in some islands a rare occurrence—on some it may not occur at all; but on other islands in the same region, the disease is prevalent.
TL;DR: In this article, the problem of steady natural convection film boiling about a heated isothermal vertical plate in a porous medium filled with a subcooled liquid was considered, and similarity solutions were obtained for the buoyancy-induced flow in the vapor and subcooling liquid layers with a distinct interface.
TL;DR: The Hawaiian-Emperor volcanic chain was formed as the Pacific lithospheric plate moved first northward and then northwestward relative to the Hawaiian hot spot, a more or less stable melting anomaly in the asthenosphere, and the bend in the chain reflects a major change in Pacific plate motion.
Abstract: The Hawaiian-Emperor volcanic chain is made up of at least 107 indentifiable shield volcanoes (Chase and others, 1970; Bargar and Jackson, 1974; Clague and others, 1980) and is the longest linear island and seamount chain in the Pacific (Fig 1) Beginning at the active volcanoes Kilauea and Mauna Loa on the island of Hawaii, this chain of volcanoes extends west-northwestward along the Hawaiian Ridge for a distance of 3,500 km, where it turns northward and continues another 2,300 km as the Emperor Seamounts, ending near the intersection of the Aleutian and Kurile Trenches It is now thought that the Hawaiian-Emperor chain was formed as the Pacific lithospheric plate moved first northward and then northwestward relative to the Hawaiian hot spot, a more or less stable melting anomaly in the asthenosphere, and that the bend in the chain reflects a major change in Pacific plate motion Several mechanisms have been proposed to explain the Hawaiian (and other) hot spots, including a propagating fracture (Betz and Hess, 1942; Jackson and Wright, 1970); diapiric upwelling along a line of structural weakness (Green, 1971; McDougall, 1971); thermal (Morgan, 1972a, 1972b) or chemical (Anderson, 1975) plumes of gravitationally unstable material rising from the deep mantle; shear melting coupled with thermal feedback (Shaw, 1973) and geographically stabilized by gravitational sinking of refractory residua (Shaw and Jackson, 1973); and extrusion induced by lateral motion along plate boundaries (Handschumacher, 1973) Despite the variety of dynamic models proposed, there has yet to be devised a definitive experiment to test any of them All these mechanisms are, however, encompassed by the general (or kinematic) hot spot hypothesis, which, when used in the broadest sense, implies neither mechanism nor excess heat