A correlation matrix of optical elements and age of the human eye.
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Adolescent↗
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Multivariate analysis of cancer mortalities for selected sites in 24 countries.
In order to analyze the pattern in the geographical distribution of cancer death in 24 countries of the world, correlation coefficients were calculated between pairs of mortality rates of different cancer sites, using the data for 13 sites in males and 14 sites in females over 18 years from 1950 to 1967. Then factor analysis by means of varimax method was performed on 13 x 13 correlation matrix for males, 14 x 14 correlation matrix for females and 27 x 27 correlation matrix for males and females combined. As a result of factor analysis, three factors are extracted, which are commonly recognized in both males and females. The first factor has high positive factor loadings on pancreas, prostate (for males), skin, and intestine cancers, and negative loadings on stomach and liver cancers. The second factor has high positive factor loading on rectum, intestine, and lung cancers, and the third factor on larynx, oral, and esophagus cancers. Factor analysis based on 27 x 27 correlation matrix revealed that the third factor of both sexes are heterogeneous with regards to the distributions of the factor score. In order that we may find some clues to develop an etiological hypothesis for each site of cancer, we obtained the correlation coefficient between the scores of the extracted factors and the variables on food and environmental agent, and performed stepwise regression methods as well. One of the most striking results we obtained was that excessive drinking of alcohol and the lack of appropriate intake of fruit are suspected as etiological promoters in the pathogenesis of oral, esophagus, and larynx cancers in males.
Adult↗
An electron microscopic study of the origin of osteoblasts in implants of demineralized bone matrix.
Correlated light microscope and ultrastructural observations of allogeneic intramuscular implants of rat demineralized bone matrix demonstrate the interrelationships between various osteogenetic and non-osteogenetic cell types and suggest that the bone morphogenetic response is evoked from cells of a common origin. Endothelial cells may play a prominent, essential, as well as primary role in the bone morphogenetic response.
Animals↗
Taxonomic congruence in Eskimoid populations.
The study compares distance relationships in Eskimoid populations based on metric and attribute data with linguistic relationships based on structural and lexicostatistical data. Taxonomic congruence and the non-specificity hypothesis are investigated by matrix correlations and by a clustering procedure. The matrix correlation approaches employed are the Pearson product-moment correlation coefficient and the Spearman rank-order correlation coefficient. An unweighted pair-group clustering procedure provides a visual comparison of biological and linguistic relationships. Data consist of 74 craniometric measurements and 28 cranial observations taken on 12 Eskimoid populations. Mahalanobis' D2 and Balakrishnan and Sanghvi's B2 were used to compute the metric and attribute distances, respectively. The results indicate that a strict adherence to the non-specificity hypothesis is untenable. Also, there is better concordance between the sexes for metric distances than for attribute distances, and the metric data are more concordant with linguistic relationships than are the attribute data.
Cephalometry↗
On the soluble phase of adrenergic nerve vesicles: correlation of matrix density and biochemical composition.
Highly purified sympathetic nerve vesicles isolated from bovine splenic nerves were treated by hypo-osmotic shocks, freeze-thawing or incubation in the absence or presence of ATP and MgCl. The vesicle preparations were then studied morphologically by electron microscopy and their content of noradrenaline (NA), and soluble proteins analyzed biochemically with special regard to dopamine beta-hydroxylase (DBH). Hypo-osmotic shocks released about 25 per cent of the NA and protein content and about 8 per cent of the DBH activity. This treatment induced swelling of the vesicles but their membranes remained unruptured and they still contained dense cores. Freeze-thawing released about 35 per cent of the NA, 25 per cent of the proteins and 11 per cent of the DBH. After the latter treatment some matrix material still remained in most vesicles but many were less stainable than the intact vesicles in cold control preparations. During incubation at 30 degrees C in an isotonic sucrose-phosphate medium for 30 min the vesicles released most of their NA and soluble DBH activity as well as much of their matrix density. After incubation at 37 degrees C for 30 min most vesicles appeared translucent. After incubation at 30 degrees C for 30 min in the presence of ATP and MgCl the vesicles lost most of their original NA content but retained their DBH activity and most of their matrix density. The results indicate that there is not always a correlation between NA content and retention of matrix density which suggests that DBH might be a component of a macro-molecular complex responsible for the staining reaction taking place in the maxtrix of NA depleted vesicles. This hypothesis is further supported by the finding of striking similarities between DBH isolated from chromaffin granules and the granular and fibrillar material surrounding the nerve vesicles after depletion.
Adenosine Triphosphate↗
Modulation of growth factor responsiveness of murine mammary carcinoma cells by cell matrix interactions: correlation of cell proliferation and spreading.
We have examined the role of growth factors and extracellular matrix in the proliferation and cell adhesion of a murine mammary carcinoma, SP1, and a stable highly metastatic variant, SP1-3M. On fibronectin, both cell types proliferated strongly in response to basic fibroblast growth factor (bFGF) and platelet-derived growth factor BB (PDGF-BB) after culture for 24 h and 72 h. In contrast, on collagen type I, SP1 cells proliferated only weakly to PDGF-BB at either time, and SP1-3M cells showed a response to PDGF-BB only at 72 h. The proliferative response to bFGF was also consistently lower when the cells were cultured on collagen than on fibronectin. No significant proliferative responses were detected to epithelial growth factor (EGF), transforming growth factor-beta (TGF-beta), or estrogen on any substratum. The lack of responsiveness to PDGF-BB of cells cultured on collagen type I was not due to differences in numbers or affinity of PDGF receptors. We therefore examined the adhesion and spreading properties of SP1 and SP1-3M cells. Without exogenous growth factors, both cell lines adhered to fibronectin and laminin. SP1-3M cells did not bind to collagen type I, whereas SP1 cells did. Attachment to all three substrata was inhibited by anti-beta 1 integrin IgG, suggesting that the primary adhesion to these substrata is mediated by beta 1 integrins. SP1 and SP1-3M cells showed similar integrin patterns following immunoprecipitation by anti-beta 1 integrin IgG. bFGF stimulated increased adhesion and spreading of both SP1 and SP1-3M cells to collagen type I within 24 h, whereas PDGF-BB was less capable of this effect. Our results suggest that the proliferative response of SP1 and SP1-3M cells to PDGF-BB and bFGF is dependent on the extracellular matrix environment, and imply that modification of extracellular matrix and/or surface integrin receptors may regulate responsiveness to these growth factors in the SP1 tumor model.
Adenocarcinoma↗
Family and couple properties, and placenta weight in the populations of Białystok and Zambrów, Poland.
The purpose of this study was an analysis of relationships between the traits of families and parents, also recognition of factors determining family properties, including factors responsible for placenta weight. Correlation matrix was used to find relationships among traits, and factor analysis with rotation of the Varimax type was used to identify factors. A total of 795 women were examined, including their placenta and family traits, in the regions of Białystok and Zambrów, in 1977-1978. A correlation matrix of 23 traits of the family and couple, and the weight of placenta during a given pregnancy, was analyzed. A total of 8 factors were discerned, explaining 61.3% of the total variation of the traits. Factor 1 (F1) represented the culture (consciousness) of the family and morbidity of the mother (15.2%), F2-parental age at pregnancy of a given mother (10.4%), F3-living conditions (8.1%), F4-arterial blood pressure of mother (8.1%), F5-body size of the mother (6.5%), F6-traits of the menstrual cycle and morbidity of the mother (5.6%), F7-body size of the father (4.7%), and F8-characterized father's morbidity (4.4%). A relatively low but statistically significant correlation was found between the weight of placenta, on the one hand, and the weight and stature of the mother and number of pregnancies, on the other hand. A little higher correlation was found between the weight of placenta and the morbidity of the mother.
Adult↗
Profiles of serum complement in patients with hepatobiliary diseases.
CH50 and the concentrations of C3, C4, C1 INH and factor B have been measured in sera from 34 control subjects and 178 patients with various hepatobiliary diseases, including primary biliary cirrhosis (PBC), chronic active hepatitis (CAH), cryptogenic cirrhosis (CC), alcoholic liver disease (ALD), Wilson's disease (WD), large duct biliary obstruction (LDBO) and viral hepatitis (VH). CH50 was decreased in CAH and CC. C3 was increased in PBC, LDBO and VH and decreased in CAH and CC. C4 was decreased in PBC, CAH, ALD and WD. C1 INH was increased in PBC, CAH, ALD, LDBO and VH. Factor B was increased in LDBO and VH and decreased in CC. In none of the patient groups was the mean C4 level increased or the mean C1 INH level decreased. All 5 indices of serum complement were lower in ascitic than nonascitic patients. Data on serum complement were similar in HBsAg positive and negative VH. Discriminant analysis facilitated separation of all the patient groups on the basis of complement data, except PBC and VA. Analysis of data using a within-group correlation matrix revealed a significant negative correlation between C4, the most discriminating variable of serum complement in CAH, and gamma-globulin concentration in CAH. The possible contribution of factors such as activation of complement, impaired hepatic synthesis of complement components, an acute phase response and cholestasis to altered serum complement profiles in different hepatobiliary diseases is discussed.
Adolescent↗
Direct estimation and inference of higher-level correlations from lower-level measurements with applications in gene-pathway and proteomics studies.
This paper tackles the challenge of estimating correlations between higher-level biological variables (e.g. proteins and gene pathways) when only lower-level measurements are directly observed (e.g. peptides and individual genes). Existing methods typically aggregate lower-level data into higher-level variables and then estimate correlations based on the aggregated data. However, different data aggregation methods can yield varying correlation estimates as they target different higher-level quantities. Our solution is a latent factor model that directly estimates these higher-level correlations from lower-level data without the need for data aggregation. We further introduce a shrinkage estimator to ensure the positive definiteness and improve the accuracy of the estimated correlation matrix. Furthermore, we establish the asymptotic normality of our estimator, enabling efficient computation of P-values for the identification of significant correlations. The effectiveness of our approach is demonstrated through comprehensive simulations and the analysis of proteomics and gene expression datasets. We develop the R package highcor for implementing our method.
Proteomics↗
Lithium RBC/plasma ratio in subgroups of patients with affective disorders.
The lithium RBC/plasma ratio was determined in 59 patients during prophylactic lithium therapy -- 10 cycloid psychotics, 28 unipolars and 21 bipolars -- as well as in 20 patients during lithium therapy in phase of illness -- 8 cycloid psychotics, 5 unipolars and 7 bipolars. The lithium ratio was found to be normally distributed both among patients in phase of remission and those in phase of illness. No differences in lithium ratio were found between patients in phase of remission and phase of illness, respectively. During prophylactic lithium therapy, no differences were found in the lithium ratio between patients in different diagnostic subgroups. In a correlation matrix, the lithium ratio was found to correlate to lithium in RBC but not to age, sex, type of illness, weight, lithium dosage, duration of treatment or level of lithium in plasma. The lithium level in RBC was determined only by the lithium level in plasma. Thus, the lithium RBC/plasma ratio does not seem to be of diagnostic value in affective disorders.
Adult↗
O2 delivery at VO2max and oxidative capacity in muscles of standardbred horses.
The purpose of this study was to describe the relationships between 16 physiological, biochemical, and morphological variables presumed to relate to the oxidative capacity in quadriceps muscles or muscle parts in Standardbred horses. The variables included O2 delivery (blood flow) and mean capillary transit time (MTT) during treadmill locomotion at whole animal maximal O2 consumption (VO2max, 134 +/- 2 ml.min-1 x kg-1), capillary density and capillary-to-fiber ratio, myoglobin concentration, oxidative enzyme activities, glycolytic enzyme activities, fiber type populations, and fiber size. These components of muscle metabolic capacity were found to be interrelated to varying degrees using correlation matrix analysis, with lactate dehydrogenase activity showing the most significant correlations (n = 14) with other variables. Most of the "oxidative" variables occurred in the highest quantities in the deepest muscle of the group (vastus intermedius) and in the deepest parts of the other quadriceps muscles where the highest proportions of type I fibers were localized. The highest blood flow measured with microspheres in the muscle group during exercise was in vastus intermedius muscle (145 ml.min-1 x 100 g-1), and the lowest was in the superficial part of rectus femoris muscle (32 ml.min-1 x 100 g-1). Average muscle blood flow during exercise at whole animal VO2max was 116 ml.min-1 x 100 g-1. Because skeletal muscle comprised 43% of total body mass (453 +/- 34 kg), total muscle blood flow was estimated at 226 l/min, which was approximately 78% of total cardiac output (288 l/min).(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
Assessment of protein-calorie malnutrition in surgical patients from plasma proteins and anthropometric measurements.
Six plasma proteins, two anthropometric measurements, hemoglobin and total lymphocytes were determined in 54 surgical patients and 19 normal individuals. Preoperative patients had a low mean values for prealbumin, retinol binding protein, and arm muscle circumference. In postoperative patients, plasma transferrin, albumin, hemoglobin, total lymphocytes and body weight were also low and complement C3 was higher than normal. A correlation matrix for 10 variables showed interrelationships between the biochemical and anthropometric data. Prealbumin and transferrin were highly correlated with most of the variables. The effects of protein-calorie malnutrition were analyzed from the data ranked and grouped according to the plasma prealbumin or transferrin concentration. Those groups with low mean values for these proteins also had low values for most of the other variables. Protein calorie malnutrition in surgical patients may be conveniently assessed from plasma prealbumin, transferrin, arm muscle circumference, percentage weight loss, and hemoglobin.
Adult↗
Latent factors in body build of newborns.
The paper is focused on relationships between traits of newborns and on discerning factors characterizing newborns more generally than individual traits. For this purpose a factor analysis was made using 35 somatic traits of 1013 newborns examined in hospitals of Zambrów and Białystok. Main components were found from the correlation matrix, and after the orthogonal rotation of the Varimax type, eight independent factors were identified. The body weight was highly correlated with circumferences of chest, calf, forearm, head, and arm. Body length was correlated with the length of lower extremities, the length of upper extremities was correlated with the length of arm and with the breadth and depth of chest, circumferences of different body parts were correlated with each other, and this was also the case of the thickness of three skin-fat-folds. The following factors were found as a result of the factor analysis (in parentheses there are traits showing highest correlations with a given factor, thus, most suitable for monitoring studies): F1-body weight (thigh circumference), F2-upper extremity length, F3-subcutaneous fat tissue (skin-fat-fold thickness on rib 10), F4-face length and nose diameters (upper-face height), F5-scapular-arm-hip diameters (scapular breadth), F6-trunk length (trunk length), F7-body length (length of lower extremities), and F8-head breadth diameters (mandible breadth).
Adipose Tissue↗
Potential antitumor agents. 29. Quantitative structure-activity relationships for the antileukemic bisquaternary ammonium heterocycles.
Quantitative relationships between physicochemical drug properties and antileukemic (L1210) efficacy have been examined for a series of bisquaternary ammonium heterocycles employing multiple variable regression analysis. Three measures of biologic response were examined: ILSmax, the percentage increase in mean life span of leukemic animals at the LD10 dose; D40, the drug dose necessary to provide 40% increase in life span; and CI (=LD 10/D40), the chemotherapeutic index. A cross correlation matrix between these three measures and the LD10 values demonstrates ILSmax and CI to be independent of toxicity. D40 is highly inversely correlated with LD10 and positively correlated with ILSmax, suggesting that this parameter measures a composite of both drug selectivity and toxicity. Superior regression equations resulted at all stages employing ILSmax as a measure of antitumor selectivity. Acceptable equations modeling LD10 could not be obtained. There was a parabolic relationship between agent lipophilic-hydrophilic balance, measured as chromatographic Rm values, and ILSmax. To reduce residual variance in the L1210 screening data, not accepted by this parabolic equation, measures of agent-DNA interaction were investigated as possible indices of site fit. Relative levels of drug-DNA interaction were obtained by spectrofluorimetric quantitation of drug displacement of DNA-bound ethidium. Addition to regression equations of agent C50 values for calf thymus DNA, those micromolar drug concentrations necessary to displace 50% of the ethidium bound to that DNA, provided a significant reduction in the screening data variance. C50 values for drug interactions with poly[d(A-T)] and poly[d(G-C)] were also investigated as possible indicators of drug selectivity towards different DNA sites. Marked differences were observed in the C50 values for the two synthetic nucleic acids, with those for calf thymus DNA and poly[d(G-C)] proving highly covariant. A regression equation containing a positive term in C50[poly[d(G-C)]] and a negative term in C50-[poly[d(A-T)]] provided the greatest acceptance of the variation in the biologic data. The term in C50[poly[d(A-T)]] is the single most important equation term, alone accounting for 35% of the variance in the data. This best equation provides both an adequate summary of the L1210 screening data for the 174 active compounds considered and a physical explanation for the antitumor selectivity for these agents. The major factor influencing antitumor selectivity in these drugs is their ability to distinguish alternating adenine-thymine sequences in DNA.
Animals↗
Physical therapist assistant selection and academic success.
Assessment of a standardized test as one criterion for student admission to a physical therapist assistant program is made. Comparisons are made of ACT scores between the physical therapist assistant and associate degree nurse, and the physical therapist assistant and the practical nurse. A correlation matrix was used to analyze data with differences among the three groups determined by t test computation. This sample supports a positive correlation of ACT test scores with graduation grade point average. The means show no significant difference between the two associate degree programs and a significant difference between the associate degree programs and the practical nurse program.
Achievement↗
Relation of food consumption to cancer mortality in Japan, with special reference to international figures.
The present study was designed to examine the epidemiological association of food consumption with cancer mortality in Japan, if any, in comparison with similar examinations in developed countries including Japan, in a search for dietary factors in cancer etiology. Whereas food consumption patterns in Japan was believed to be specific among developed countries, this study revealed that the correlation matrix among major foods both for international and Japanese data made it possible to categorize these foods into two groups with some similar patterns, since there should be observed a positive or negative correlation for each pair of foods. The patterns for correlation of food consumption to cancer mortality in Japan were found to be considerably different from those in developed countries, and this suggested that the epidemiological association between the two in Japan, if any, could be specifically evaluated from that in develop countries. The urban-type region for food consumption in Japan, however, indicated a possible westernization for the relation of food consumption to cancer mortality as well as for food consumption patterns, whereas the traditional Japanese region for food consumption did not indicate any similarity with westernization for the relationship between food consumption and cancer mortality, as well as for food consumption patterns. The above findings also suggested that there might be a possible significance for the regionalization of Japan in such studies, and that the urbanization of food consumption patterns in Japan would show that this country has a similar pattern of association between food consumption and cancer mortality as observed among developed countries in Europe and/or North America.
Dairy Products↗
HLA--D typing with lymphoblastoid cell lines. IV. Allelic relationships.
Responses of approximately 200 persons were measured by mixed leukocyte cultures against 41 lymphoblastoid cell lines which were thought to be homozygous for HLA--D (i.e. LCL-HTCs). These responses were standardized by computer analysis and the resultant Interaction Indices for each LCL-HTC were compared with those of every other LCL-HTC in a correlation matrix of 861 independent analyses. Only those analyses involving LCL-HTCs of defined HLA--D types are reported here. In general, these studies confirmed many allelic relationships of reputedly similar LCL-HTCs; however, several unexpected groups of correlations suggested that groups Dw1 and 3 overlap to form Groups "1a-3," "1b-3" and "true 3." The "1b-3" group also included Dw8. Segregation of the "1b-3" allelic group was also observed in a family study. These preliminary analyses suggest a working model for further investigation of HLA--D allelic relationships (Fig. 3). On the other hand, they may also be interpreted to suggest that "typing" with LCL-HTCs may be controlled by a separate HLA locus which is closely related to, but distinct from, HLA--D.
Alleles↗
Epidemiology of poly-parasitism. II. Types of combinations, relative frequency and associations of multiple infections.
Frequency distributions, including all of the observed types of combinations of multiple infections with different helminths and protozoa are presented for sample villages of the African Savannah and of the trans-Andean part of Peru. Measurements of correlation between these infections based on properties of the multivariate, multinomial distribution are calculated to show age and sex patterns of association in different population samples. A correlation matrix for combined infections with Dipetalonema perstans, D. streptocerca and Loa loa, in villages in the rain forest of Zaire indicates that there is a statistically significant association between the two species of Dipetalonema and L. loa. There is also a strong association between the numbers of the microfilariae of D. perstans and D. streptocerca in multiply infected individuals. This correlation is strong only in the rain forest; it is insignificant in the other ecological zones of Bas-Zaire included in the study. The data suggest that there may be selective host factors that influence the extent, distribution and the types of multiple infections in a community.
Adolescent↗