Showing papers by "University of Arizona published in 1975"

A clinical staging system for multiple myeloma. Correlation of measured myeloma cell mass with presenting clinical features, response to treatment, and survival

Abstract: The presenting clinical features of 71 patients with multiple myeloma were correlated with myeloma cell mass (myeloma cells X 10(12)/m2 of body surface area) determined from measurements of monoclonal immunoglobulin (M-component) synthesis and metabolism. Bivariate correlation and multivariate regression analyses showed that myeloma cell mass could be accurately predicted from A) extent of bone lesions, B) hemoglobin level, C) serum calcium level, and D) M-component levels in serum and urine. Analyses of response to chemotherapy and survival indicated significant correlation with measured myeloma cell burden. The results were synthesized to produce a very reliable and useful clinical staging system with three tumor cell mass levels (Table 7). For clinical research purposes, multivariate regression equations were developed to predict optimally the exact myeloma cell mass. Thus, initial staging can be quantitatively related to followup using tumor cell mass changes calculated from changes in M-component production. Use of the clinical staging system sould provide better initial assessment and followup of individual patients, and should lead to improved study design and analysis in large clinical trials of therapy for multiple myeloma.

Induced thermal resistance in HeLa cells

Abstract: IN mammalian cells, hyperthermia causes temperature-dependent changes in cell growth parameters1, reduces DNA and protein synthesis rates2 and cell metabolism3, and leads to a loss of proliferative capacity4,5. Harris6 has shown that temperature-resistant pig kidney cells can be obtained after multiple exposures to very high thermal doses (colony-forming ability reduced to 10−5–10−6 of controls). The purpose of our experiments was to determine whether a single hyperthermic treatment (44 °C for 1 h) could induce a state of thermotolerance in cells, and if so, what was the mode of origin of the thermal resistant cells.

Versatile Elastic-Plastic Stress-Strain Formula

Abstract: In the analysis of nonlinear structural systems, the stress-strain (force-deflection moment-rotation) relationship must be represented mathematically. The most simple representation is a series of straight lines. An alternative procedure is to fit a smooth analytical expression to the expression is the Ramberg-Osgood three-parameter polynomial which gives strain explicitly in terms of stress.

Regulation of serum 1alpha,25-dihydroxyvitamin D3 by calcium and phosphate in the rat.

Abstract: A new radioreceptor assay was used to quantify changes in serum concentration of 1alpha,25-dihydroxyvitamin D3 in rats with low calcium or low phosphate diets. Low availability of either ion elicits a fivefold increase in the circulating concentration of 1alpha,25-dihydroxyvitamin D3. The enhancement of 1alpha,25-dihydroxyvitamin D3 concentration in response to calcium deficiency is dependent on the presence of the parathyroid or thyroid glands (or both), suggesting that this effect is mediated by parathyroid hormone. In contrast, the response of phosphate deficiency is independent of these glands and may result from an action of low serum phosphate concentration or some factor associated with phosphate depletion on the renal synthesis of the 1alpha,25-dihydroxyvitamin D3 hormone.

Use of an ac heterodyne lateral shear interferometer with real-time wavefront correction systems.

Abstract: An analysis is performed to determine the accuracy with which an ac heterodyne lateral shear interferometer can measure wavefront aberrations if a white light extended source is used with the interferometer, and shot noise is the predominate noise source. The analysis shows that for uniform circular or square sources larger than a derived minimum size, the wavefront measurement accuracy depends only upon the radiance of the source and not upon the angular subtense of the source. For a 1-msec integration time, a 25-cm(2) collecting area, and a source radiance of 10 W/m(2)-sr the rms wavefront error is approximately 1/30 wave, assuming the signal is shot noise limited. It is shown that for both uniform circular and square sources an optimum shear distance is approximately (1/2) the aperture diameter required to resolve the light source. Comments are made on the optimum shear for nonuniform radiance distributions.

Structure-function relationships in glucagon: properties of highly purified des-His-1-, monoiodo-, and (des-Asn-28, Thr-29)(homoserine lactone-27)-glucagon.

Abstract: We have compared the ability of glucagon and three highly purified derivatives of the hormone to activate hepatic adenylate cyclase (an expression of biological activity of the hormone) and to compete with [125]glucagon for binding to sites specific for glucagon in hepatic plasma membranes. Relative to that of glucagon, biological activity and affinity of [des-Asn-28,Thr-29](homoserine lactone-27)-glucagon, prepared by CNBr treatment of glucagon, were reduced equally by 40- to 50-fold. By contrast, des-His-1-glucagon, prepared by an insoluble Edman reagent and highly purified (less than 0.5% contamination with native glucagon), displayed a 15-fold decrease in affinity but a 50-fold decrease in biological activity relative to that of the native hormone. At maximal stimulating concentrations, des-His-1-glucagon yielded 70% of the activity given by saturating concentrations of glucagon. Thus, des-His-1-glucagon can be classified as a partial weak agonist. Highly purified monoiodoglucagon and native glucagon displayed identical biological activity and affinity for the binding sites. Our findings suggest that the hydrophilic residues at the terminus of the carboxy region of glucagon are involved in the process of recognition at the glucagon receptor but do not participate in the sequence of events leading to activation of adenylate cyclase. The amino-terminal histidyl residue in glucagon plays an important but not obligatory role in the expression of hormone action and contributes to a significant extent in the recognition process.

A Labor Theoretic Analysis of Criminal Choice

Abstract: In this paper we show that plausible preference restrictions are not sufficient for unambiguous household supply results in the criminal choke problem. Therefore policy prescriptions in this area do not follow from theory, but rather require empirical determination of relative magnitudes.

Consumption of classical complement components by heart subcellular membranes in vitro and in patients after acute myocardial infarction.

Abstract: Experiments were conducted to characterize the antibody-independent activation of complement in human serum by isolated human heart mitochondrial membranes in vitro and to determine whether similar patterns of complement consumption occurred in patients after acute myocardial infarction. Direct evidence for the interaction of C1 and heart mitochondrial membranes was obtained by mitochondria-C1 binding and elution experiments. Exposure of normal human sera to isolated human heart mitochondria at 37 degrees C resulted in the consumption of C1, C4, C2, and C3 without significant consumption of the terminal components of the complement system (C6 through C9). The consumption occurred in the absence of detectable anti-heart mitochondria autoantibody, was demonstrated to be calcium dependent, and was inhibited by either 0.01 M EDTA or ethylene glycol bis(bets-aminoethyl ether) N,N,N',N',-tetraacetic acid (EDTA). Although specific absorption of C1q from human sera inhibited the mitochondria-dependent activation of C4, C3 donsumption was not affected. These data indicate that the consumption of C4 and C2 likely occurred due to the mitochondrial membrane-mediated activation of C1, but that the consumption of the C3 did not necessarily involve either the classical or alternative complement pathways. After the in vitro characterization of the mitochondria-dependent activation of the complement system, additional studies were performed to determine whether similar consumption occurred in patients after acute myocaridal infarction. During a 72-h period after hospital admission significant decreases in C1, C4, and C3 occurred in six patients with recent chest pain but no evidence of acute myocardial infarction. These studies suggest that myocardial cell necrosis results in the release of subcellular membrane constituents capable of activating the complement system in the absence of detectable anti-heart autoantibodies; such activation may be responsible in part for the development of acute inflammation and evolution of the infarct size following coronary artery occulusion.

Combination chemotherapy with adriamycin and cyclophosphamide for advanced breast cancer.

Abstract: Fifty-five consecutive women with advanced breast cancer were treated with a combination of adriamycin (40 mg/m2 administered intravenously on day 1 ) and cyclophosphamide (200 mg/mP/day given orally in divided doses for 4 days on days 3-6). Courses were repeated at 21-28-day intervals. The mean age for the 55 patients was 55 years (range, 37-77 years); 20% of the patients were 65 years or older. All patients were evaluable. Objective response (at least a 50% decrease in the size of all measurable lesions lasting for at least 1 month) was noted in 40 (80%) of the 50 patients who received an adequate trial of chemotherapy (a minimum of two courses). Six of the 40 responses observed were complete. The median duration of response was 10 months. Actuarial survival for the entire group of 55 patients was 80% at 6 months after initiating chemotherapy and 70% at 12 months. Survival for the 40 responding patients was 95% at 6 months and 80% at 12 months. Response rates by site of involvement were: soft tissue, 20/25 (80%); lymph node, 15/19 (79%); bone, 21/25 (84%); lung, 15/18 (83%); pleural effusion, 6/8 (75%); and liver, 7/10 (70%). Eighty-three percent of the responses were apparent after two courses of treatment and 98% were apparent after four courses. Toxicity was acceptable and included nausea, myelosuppression, alopecia, and reversible congestive heart failure (in 2 patients who received 550 mg/mz of adriamycin). Chemotherapy with adriamycin and cyclophosphamide proved to be safe and effective for outpatient treatment of advanced breast cancer. Crmcn 36:90-97, 1975.

Light-scattering characteristics of optical surfaces

Abstract: A scalar theory of surface scattering phenomena has been formulated by utilizing the same Fourier techniques that have proven so successful in the area of image formation. An analytical expression has been obtained for a surface transfer function which relates the surface micro-roughness to the scattered distribution of radiation from that surface. The existence of such a transfer function implies a shift-invariant scattering function which does not change shape with the angle of the incident beam. This is a rather significant development which has profound implications regarding the quantity of data required to completely characterize the scattering properties of a surface. This theory also provides a straight-forward solution to the inverse scattering problem (i.e., determining surface characteristics from scattered light measurements) and results in a simple method of predicting the wave length dependence of the scattered light distribution. Both theoretical and experimental results will be presented along with a discussion of the capabilities and limitations of this treatment of surface scatter phenomena.© (1977) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Production and Utilization of Seeds in Plains Grassland of Southeastern Arizona

Abstract: In the plains grassland in southeastern Arizona there are two peaks of seed production. Following the winter rains, seeds are produced which are subject to relatively high predation by ants and rodents, and following the summer rains seeds are produced which are subject to relatively high predation from sparrows and rodents but not ants. The differences in seed selection by ants and sparrows have apparently been important in determining the evolution of seed morphology and phenology. Seeds produced after the winter rains are smooth in outline and difficult for ants to carry. Seeds produced after the summer rains have con- spicuous awns, hairs, or other projections and usually require husking by sparrows. The bill structure of sparrows is such that they can more easily eat the species of seeds which become available after the winter rains, but this is the time when sparrows switch their diets from seeds to insects. The mandibular structure of Pogototinyrmtlex ants makes it difficult for them to harvest the seeds of smooth outline as are produced after the winter rains. The seeds which ants can most easily transport back to their nests are those species produced only after the sUmmer rains and which ripen just as autumn cold forces the ants underground. Thus, the plants appear to have adapted the morphology of their seeds and their reproductive phenology to minimize predation. Interclass competition for seeds by ants, sparrows, and rodents is minimized by a complex combination of factors involving seed selection, differences in seasonal activity, and the bi- modal nature of seed production. What interclass competition that might exist is probably manifest only in years of low seed production.

The motor units of cat medial gastrocnemius: Electrical and mechanical properties as a function of muscle length

Abstract: The effects of changing muscle length on the mechanical properties of 89 motor units from adult cat medial gastrocnemius have been studied in eight experiments. Few differences were found between the effects of length on tetanic tension, twitch tension, twitch-tetanus ratio, twitch contraction time, twitch half relaxation time, rate of force development and electrical activity for fast contracting (twitch contraction time less than or equal to 45 msec) and slowly contracting (greater than 45 msec) units. Those differences that did appear did not persist when these two groups were matched by tetanic tension. It is concluded that the biophysical mechanisms responsible for the changes in mechanical and electrical properties with length must be similar for fast and slow twitch units and not related to potential differences in their muscle fiber type. The effects of changing muscle length on the mechanical properties of the eight whole muscles suggest that changes in force output with length are of minor importance during normal movements as the muscle is found to be electrically active over a relatively narrow range of lengths close to the optimum length for tetanus of the whole muscle. The very shortest muscle lengths at which there is only minimal force development are not used in natural movements, while the declining limb of the length tension curve is at muscle lengths beyond the maximum in situ length.

The peculiar object HD 44179 /'The red rectangle'/

Abstract: A strong infrared source detected in the AFCRL sky survey is confirmed, and is identified with the binary star HD 44179, embedded in a peculiar nebula. UBVRI and broad-band photometry between 2.2 and 27 microns are combined with blue, red, and near-infrared spectra, polarimetry and spectrophotometry of the star, and a range of direct and image-tube photographs of the nebula, to suggest a composite model of the system. In this model, the infrared radiation derives from thermal emission by dust grains contained in a disklike geometry about the central object, which appears to be of spectral type B9-A0 III and which may be in pre-main-sequence evolution. Two infrared emission features are found, peaking at 8.7 and 11.3 microns, the latter corresponding to the feature seen in the spectrum of the planetary nebula NGC 7027. The complex nebular structure is discussed on the basis of photographs through narrow-band continuum and emission-line filters. The polarization data support the suggestion of a disk containing some large particles. No radio continuum emission is detected.

Cytoplasmic and nuclear binding components for 1alpha25-dihydroxyvitamin D3 in chick parathyroid glands

Abstract: Specific binding of 1 alpha,25-dihydroxyvitamin D3 [1alpha,25-(OH)2D3] to macromolecular components in the cytoplasm and nucleus is demonstrated in parathyroid glands of vitamin-D-deficient chicks. The interaction of 1alpha,25-(OH)2D3 with the cytoplasmic binding component is of high affinity (Kd = 3.2 X 10(-10) M) and high specificity [1alpha,25-(OH)2D3 greater than 25-hydroxyvitamin D3 greater than 1alpha-hydroxyvitamin D3 greater than vitamin D3 in competing with radioactive 1alpha,25-(OH)2D3]. Both cytoplasmic and nuclear hormone-macromolecular complexes sediment at 3.1 S in 0.3 M KC1-sucrose gradients, and agarose gel filtration of the components indicates an apparent molecular weight of 58,000. The 3.1S binding molecules are not observed in adrenal gland, testes, liver, or kidney, but similar receptors for 1alpha,25-(OH)2D3 have been found previously in intestine. Macromolecular species with a high affinity and preference for 25-hydroxyvitamin D3 [25-(OH)D3] are also identified in parathyroid cytosol and differ from the parathyroid 1alpha,25-(OH)2D3-binding component in that: (1) they sediment at 6 S in 0.3 M KC1-sucrose gradients, (2) they are observed in all tissues examined, (3) they have a higher affinity for 25-(OH)D3 than 1alpha,25-(OH)2d3, and (4) they are not found in the nucleus of the parathyroid glands, in vitro. The discovery of unique 1alpha,25-(OH)2D3-binding components in the parathyroid glands is consistent with the sterol hormone's action at this endocrin site and possible involvement in the regulation of parathyroid hormone synthesis and secretion.

Problems and Solutions in Estimating the Demand for and Value of Rural Outdoor Recreation

Abstract: An improved methodology for estimating demand functions for outdoor recreation and evaluating the outdoor recreation resource by use classification is presented. The illustrative framework is a large-scale empirical study of all outdoor recreation activities in all areas of Arizona. The use of the improved procedures produces estimates of resource values which are much larger than in most previous studies and which are about the size of estimates of gross variable expenditures. It is argued that the time has come to relax the search for improved estimating methodology and concentrate on interpretation of the estimates in studies of resource allocations.

High Speed Scintillation Autoradiography

Abstract: Impregnation of nuclear track emulsion with liquid scintillator and exposure at -85 degrees C allows rapid autoradiographic labeling. With tritiated thymidine of high specific activity (40 to 60 curies per millimole), exposure time can be shortened to 20 to 60 minutes, allowing complete sample processing within 4 hours. In experiments requiring isotopes with low incorporation rates or low specific activity, exposure time can be shortened from months to several days.

Does Money Buy Satisfaction

Abstract: There was no change in the distribution of satisfaction with the standard of living among Detroit area wives between 1955 and 1971, although current-dollar median family income more than doubled and constant-dollar income increased by forty per cent. Cross-sectional variation in satisfaction is, however, related to income and, in particular, to relative position in the income distribution. Whereas regressions of satisfaction on income in current or constant dollars, or the logarithm thereof, suggest that at the same income there was less satisfaction in 1971 than in 1955, there is no significant year effect in the equation using the income-position variable. Easterlin’s thesis that rising levels of income do not produce rises in the average subjective estimate of welfare is supported. The thesis raises difficult questions for students of subjective social indicators.

Jupiter's Magnetic Field. Magnetosphere, and Interaction with the Solar Wind: Pioneer 11

Abstract: Measurements of the magnetic field vector were obtained continuously throughout the encounter of the spacecraft with the planet Jupiter. Effects of Jupiter on the solar wind are considered along with the characteristics of the magnetopause at both low and intermediate latitudes, the three basic regions within the magnetosphere, and a spherical harmonic analysis of the Pioneer 11 measurements. The spherical harmonic representation has been used to derive contours of the magnetic field strength at the surface of Jupiter.

Strong scintillations in astrophysics. II - A theory of temporal broadening of pulses

Abstract: A theory of temporal broadening of pulses propagating in a turbulent medium is developed on the basis of the Markov approximation. The theory may be applied to quite general turbulence spectra and to thin or thick turbulent regions. Since the basis of the theory is the wave equation, no reliance is placed on geometrical optics and no assumptions are made about the scattered angular spectrum. The observed smearing is found to be the combination of three effects: the dispersion effect, the pure refractive effect, and the diffraction effect. The last of these dominates for typical pulsar parameters. Pulse shapes are calculated for both Gaussian and Kolmogorov turbulence spectra and it is shown how these scale with the various turbulence parameters.

The Division of Labor: Conceptualization and Related Measures

Abstract: The division of labor refers to differences among members of a population in their sustenance activities and the related functional interdependence. It is proposed that the first dimension of the division of labor, sustenance differentiation, may be measured with data on occupational composition. Six alternative measures are presented and evaluated. Emphasis is placed on the attention each gives to the two aspects of sustenance differentiation: structural differentiation (number of classes) and distributive differentiation (distribution of individuals among the classes). The notion of a division of labor has had a strange history in the social sciences. In light of classical studies by Adam Smith (1776) and Emile Durkheim (1893), no economist or sociologist would question the importance of the phenomenon. But since these two classics did not engender a viable tradition of research and theory, there has been little progress in the conceptualization or measurement of the division of labor. (See the recent commentary by