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PubMed1981

Validity of the Missouri Children's Picture Series as a predictor of childhood sleep disturbances.

In view of recent findings in a retrospective study by two of the authors, the present research was designed to systematically assess the validity of the Missouri Children's Picture Series sleep disturbances scale. Study I compared groups of restless sleepers and nocturnal enuretics with matched cohorts attending a summer residential program for children with communication-related disorders. Study II examined the relation of two MCPS scales to parent reports of corresponding problems, using a multitrait-multimethod matrix, individual correlations, and cluster analysis. Neither study provided convincing evidence for the validity of the sleep disturbance scale.

Adolescent↗
PubMed1991

Antiphosphotyrosine immunoprecipitation of an insulin-stimulated receptor phosphatase activity from FRTL5 cells.

Phosphotyrosine-containing proteins (PYPs) from FRTL5 epithelial cells were immunoprecipitated with Sepharose-linked phosphotyrosine antibody and phosphorylated in vitro with insulin and insulin-like growth factor-I (IGF-I) receptor kinases. Insulin preactivation of the kinases resulted in increased phosphorylation of a single 175,000 mol wt PYP (p175) beside insulin and IGF-I receptors. Phosphorylation of both p175 and receptors exhibited almost identical time courses and insulin dose responses, suggesting that p175 may serve as a substrate for the insulin and IGF-I receptor kinases. Preincubation of autophosphorylated receptors with PYPs derived from insulin-stimulated cells decreased 32P-labeled receptor precipitation by antiphosphotyrosine-Sepharose by 50-70% compared to that obtained upon preincubation with PYPs from unstimulated cells. This effect was not the result of PYP-receptor competition, was observed on both in vivo and in vitro phosphorylated receptors, and was almost completely blocked by 100 microM sodium vanadate, suggesting PYP copurification of a phosphotyrosine phosphatase. No phosphatase was recovered in lysates from insulin-unstimulated cells. Maximum activity was detected after 2 min of insulin stimulation, decreasing by more than 50% after 30 min. Antiphosphotyrosine recovery of p175 from cell lysates exhibited almost identical insulin dependency. Complete recovery of both p175 and phosphatase activity was obtained after receptor immunodepletion of the extracts. Thus, a receptor phosphatase activity from insulin-stimulated FRTL5 cells is retained on an antiphosphotyrosine affinity matrix and correlates with phosphorylation of the p175 substrate for the insulin and IGF-I receptor kinases.

Animals↗
PubMed1995

Adaptation to homelessness: self-actualization, loneliness, and depression in street homeless men.

Adaptation to homelessness was investigated in a sample of 145 street homeless men using loneliness and depression scales and the construct of self-actualization. Principal components analysis with varimax rotation of a matrix of correlations of measures on the history of being homeless, demographic data, scores on loneliness and depression scales, and self-actualization measures gave a 3-factor model of adjustment: adaptive striving, detachment, and adaptive resources. Maslow's and Sullivan's contention that satisfying interpersonal relationships are common pathways to mental health was affirmed.

Adaptation, Psychological↗
PubMed1999

Mathematical representations of correlations among yield traits and somatic cell score on test day.

Prediction of lactation yields and accuracies of yields for use in genetic evaluation can be improved by including information from test day correlations, especially for milk recording plans that vary in the numbers of milk weights recorded and component samples taken. Daily milk weights for 658 lactations of Canadian cows and monthly test records of milk, fat, and protein yields and somatic cell scores for 500,000 lactations of US cows were used to estimate phenotypic correlations between test days within herd-year. Correlations between daily yields for a designated interval between test days generally were highest for midlactation and were lowest for early and late lactation. Regression (two linear, two quadratic, and interaction effects) on mean DIM and interval between test days predicted correlations with a squared correlation of 0.94 for daily milk yields. Similar relationships were found for US monthly data. Variation in sampling was reduced, computer memory was minimized, and positive definiteness was guaranteed by fitting regressions on simply defined sources of correlation. An autoregressive matrix represented the within-trait correlations very well. The equations developed could be used to derive covariances and, subsequently, to estimate lactation yields and accuracies from combinations of individual daily milk, fat, and protein yields and somatic cell score.

Animals↗
PubMed1999

Correlation between expression of the matrix metalloproteinase-1 gene in ovarian cancers and an insertion/deletion polymorphism in its promoter region.

Matrix metalloproteinases (MMPs), a family of closely related enzymes that degrade the extracellular matrix, are likely to be involved in invasion and metastasis of tumor cells. A guanine (G) insertion/deletion polymorphism within the promoter region of MMP-1 influences the transcription of this gene; i.e., the 2G (insertion-type) promoter possesses greater transcriptional activity than the 1G (deletion-type) promoter. To investigate whether this feature contributes to cancer development and/or progression, we genotyped 163 ovarian cancer patients for the polymorphism and then analyzed levels of expression of the MMP-1 gene in their tumors. The proportion of patients who were either heterozygotes or homozygotes for the 2G allele was significantly higher than that observed among 150 individuals without cancer (P = 0.028). Moreover, the levels of MMP-1 expression in cancer tissues among the patients carrying 2G alleles were elevated significantly in comparison with 1G homozygotes (P = 0.0038). By stimulating degradation of extracellular matrix, an excess of MMP-1 production may enhance development and/or rapid progression of ovarian cancers.

Collagenases↗
PubMed2001

Induction of fibroblast-like cells from CD34(+) progenitor cells of the bone marrow in rheumatoid arthritis.

To assess the role of bone marrow in the pathogenesis of rheumatoid arthritis (RA), we examined the capacity of CD34(+) cells from bone marrow to generate fibroblast-like type B synoviocytes. CD34(+) cells from the bone marrow of 22 RA patients differentiated into cells with fibroblast-like morphology, which expressed prolyl 4-hydroxylase, in the presence of stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor alpha (TNF-alpha), much more effectively than CD34(+) cells from bone marrow of 15 control subjects (10 patients with osteoarthritis and 5 healthy individuals). The generation of fibroblast-like cells was not at all observed in cultures with SCF, GM-CSF, and interleukin 4 (IL-4) with or without TNF-alpha. Generation of fibroblast-like cells was correlated with matrix metalloproteinase (MMP)-1 levels in culture supernatants. Thus, MMP-1 levels were significantly higher in TNF-alpha-stimulated cultures of bone marrow CD34(+) cells from patients with RA than in those from the control group. These results indicate that bone marrow CD34(+) cells from patients with RA have abnormal capacities to respond to TNF-alpha and to differentiate into fibroblast-like cells producing MMP-1, suggesting that bone marrow CD34(+) progenitor cells might generate type B synoviocytes and thus could play an important role in the pathogenesis of RA.

Adult↗
PubMed2002

Expression of cell-cycle-regulated proteins pRb2/p130, p107, p27(kip1), p53, mdm-2, and Ki-67 (MIB-1) in prostatic gland adenocarcinoma.

PURPOSE: The quest for prognostic molecular markers in prostatic carcinoma is still in progress. Many proteins have already been screened by immunohistochemistry with the aim to find the most reliable indicator of progressive disease. In this study, we evaluated the expression of pRb2/p130, p107, p27(kip1), p53, mdm-2, and Ki-67 (MIB-1) by immunohistochemistry in 24 prostate carcinomas compared with the paired expression of normal prostates. EXPERIMENTAL DESIGN: Expression of the different proteins in normal and pathological specimens was evaluated by the Wilcoxon test. A matrix of correlation (Spearman coefficient) was used to evaluate the possible association in expression among the different proteins. Logistic regression analysis was used to test the multivariable prognostic value of the levels of protein expression for the probability of disease development. RESULTS: p53 and Ki-67 (MIB-1) showed a higher expression in cancer than in normal tissue (P = 0.006 and <0.001, respectively). pRb2/p130, p107, and p27(kip1) showed an overall lower expression in cancer, but the difference between cytoplasmic and nuclear expression was always higher for cancer (Ps, from <0.001 to 0.016). mdm-2 expression was lower in cancer, but the difference between cytoplasmic and nuclear expression was not significant (P = 0.571) when compared with that in normal tissue. A positive correlation between p27 and pRb2/p130 levels expressed, in normal and cancer counterparts in the same sample, as the difference between cytoplasmic and nuclear protein concentrations (P = 0.045) was found. Additionally, p107 expression showed an inverse correlation with Ki-67 (MIB-1) expression in the most aggressive tumors (P = 0.046). Logistic regression output showed that Ki-67 (MIB-1) and pRb2/p130 (expressed as differences between cytoplasmic and nuclear concentrations) were the variables associated with a higher risk of cancer. The highest value was reported for Ki-67 (MIB-1) (odds ratio, 2.11), followed by pRb2/p130 (odds ratio, 1.01). pRb2/p130 alone was associated with a sensitivity (rate of cases having a posterior probability of disease >/=0.5) of 61% with a false positive rate of 22%. Ki-67 (MIB-1) alone yielded a sensitivity of 69% and a false positive rate of 14%. The combined model (Ki-67 + pRb2/p130) yielded a sensitivity of 83% with a false positive rate of 17%. Interestingly, one specimen in which we also found a high-grade prostatic intraepithelial neoplasia showed the progressive loss of pRb2/p130 from normal prostatic cells to prostatic intraepithelial neoplasia cells, suggesting that in prostatic cancer, lack of expression of the tumor suppressor gene pRb2/p130 could be involved in the progression of the disease, from an early stage. CONCLUSIONS: This study showed that all of the proteins but mdm-2 were expressed at a different rate in normal and pathological prostate specimens. Multivariate analysis showed that pRb2/p130 and p107 may be involved in the pathogenesis and progression of prostate cancers, and that the expression of the retinoblastoma-related protein pRb2/p130 along with Ki-67 (MIB-1), expressed as differences between cytoplasmic and nuclear concentrations, could be considered new parameters to be evaluated in discriminating patients at a higher risk for prostate cancer.

Adenocarcinoma↗
PubMedDate not supplied

Comparison of abdominal muscle strength in post-parous and nil parous subjects.

This study investigated the relationship between parity and abdominal muscle strength using the Kraus-Weber test. Female volunteers (700) comprising 350 post-parous and 350 nil-parous subjects participated in the study. Physical characteristics of the subjects (age, body weight, height and ponderal index) were measured while the abdominal muscle strength was assessed using three of the six-item Kraus-Weber tests. Results were analysed using descriptive and inferential statistics. Independent t-test showed a significant difference in values of the abdominal. muscle strength of the post-parous and nil-parous subjects (P < 0.05). Pearson's correlation's matrix showed an inverse relationship between parity and scores on the Kraus-Weber test in the post-parous subjects. A significant difference was observed across the parity groups in age, Ponderal index and scores on the Kraus-Weber tests. It was concluded that the abdominal muscle strength of the post-parous subjects was low compared to nil-parous subjects. Due to the ease of application and its non-dependence on the use of sophisticated equipment, it was recommended that the Kraus-Weber test should be used for both subjective assessment and training of abdominal muscle strengths.

Abdominal Muscles↗
PubMed1991

Variants of SLE--a statistical approach for discrimination of a group of SLE cases into different subgroups sharing symptomatology. A pilot study.

Symptoms of two groups of Systemic lupus erythematosus (SLE) (Group 1 constituted 65 patients examined from 1975 to 1981; Group 2 constituted 104 patients examined from 1980 to 1988), which were diagnosed according to the American Rheumatism Association (ARA) preliminary criteria, were statistically analyzed with the use of a package of statistical programs which included computation of a matrix of correlation and cluster analysis. In both groups similar frequency and associations of SLE symptoms were seen. Hence, there was a positive correlation between kidney involvement and hematological abnormalities with nDNA Abs what was a hallmark of a severe SLE. In contrast, the symptoms of severe SLE disease was rarely seen in cases with Raynaud's phenomenon and discoid lesions. Our cluster analysis further distinguished groups on the basis of renal involvement, skin symptomatology, and polyserositis. These results also were similar in both groups of patients. That gave further credence to our results and continued to support the concept of SLE variants being distinguished on the basis of the clinical picture.

Antibodies, Antinuclear↗
PubMedDate not supplied

Relationship between physical impairment, psychological variables and pain in rheumatoid disability. An analysis of their relative impact.

Forty-two consecutive female rheumatoid patients were given the AIMS questionnaire in order to determine their disability. Twenty-one had a second assessment one year later. Factorial analysis showed that the Italian version fully respects the construct of the original test. In fact four main factors (the physical, psychological, social and pain dimensions) arose, explaining 44.8%, 13.6%, 11.4% and 9% of the total variance, respectively. A close relationship was demonstrated between psychological variables, namely depression, and physical impairment, as shown by the correlation coefficient matrix. In order to determine whether depression might influence the ultimate outcome twenty-one patients were separated into two subsets according to their initial depression (greater than 5, less than 5). After one year, dexterity and pain were significantly worse in those with the highest depression score. This study shows that the psychological variables, in addition to physical impairment and pain, are of utmost importance in the outcome of rheumatoid patients.

Adult↗
PubMed1990

Effect of glucocorticoids on oncogene transformed NIH3T3 cells.

We studied the differential response of oncogene transformed NIH3T3 cells to glucocorticoids. As demonstrated for transformed human fibroblasts, the morphology of neu-, ras-, src- and sis-transformed mouse fibroblasts became more normal after glucocorticoid treatment. This change was not due to inhibition of the expression of oncogene mRNA or protein. However, the abl-transformed NIH3T3 cells were resistant to glucocorticoid-induced morphology change. These results indicate that the glucocorticoid-induced morphology change is specific to certain oncogene-transformed NIH3T3 cells. Transformed human fibroblasts generally have reduced amounts of cell surface fibronectin. When treated with glucocorticoids, they incorporate higher levels of fibronectin in their extracellular matrix, which correlates with their change in morphology. However, we found that, except for abl-transformed cells, the fibronectin level of the other oncogene transformed mouse cells was similar to non-transformed cells. Moreover, treatment of the neu-, ras-, src- and sis-transformed cells with glucocorticoids resulted in a change in morphology but no increase in cell surface fibronectin. These studies demonstrate that the glucocorticoid-induced morphological change of oncogene-transformed NIH3T3 cells is not due to enhanced expression of fibronectin. Therefore, other mechanisms are responsible for this glucocorticoid-induced phenotypic change of oncogene-transformed cells.

Cell Transformation, Neoplastic↗
PubMed1988

Modulation of keratinocyte motility. Correlation with production of extracellular matrix molecules in response to growth promoting and antiproliferative factors.

Normal human epidermal keratinocytes (KC) grown under conditions that maintain the undifferentiated state are highly motile. Migration of these cells as measured in two different assays (migration out of an agarose drop explant, and into micropore filters in a modified Boyden chamber), is stimulated by fibronectin (FN) and to a lesser extent by thrombospondin (TSP). In contrast, laminin (LN) inhibits KC migration. Cultivation of the cells for 1 day under conditions that induce differentiation (ie, in the presence of 1.4 mM Ca2+) suppresses KC motility. A number of soluble growth modulating polypeptide factors also influence KC migration. Transforming growth factor-beta (TGF-beta) and epidermal growth factor (EGF) stimulate KC motility. These factors simultaneously induce KC production of FN and a significant portion of the stimulated motility can be inhibited with antibodies to FN. EGF and somatomedin-C (SM-C), but not TGF-beta, also stimulate TSP production while EGF and SM-C (but not TGF-beta) induce KC proliferation. In contrast to these factors, interferon-gamma (INF-gamma) inhibits KC production of both FN and TSP and concomitantly inhibits both motility and proliferation. These data suggest that KC properties essential for normal wound healing (ie, motility and proliferation) are regulated by both extracellular matrix molecules and soluble peptide factors. Finally, these effects of various growth promoting and antiproliferative factors on KCs may, in part, be mediated through alteration in the endogenous production of extracellular matrix molecules by KCs.

Cell Division↗
PubMed1988

Comparative biochemical and morphometric studies on corneal wound healing.

Comparative biochemical and morphological studies were carried out on wounded corneas in order to correlate biochemical findings with morphometric observations during the healing process. Experimental production of corneal wounds, biochemical determinations and quantitative morphometric studies are described in an attempt to correlate corneal matrix macromolecules biosynthesis during the healing process with the morphological modifications of the tissue. The central part and the peripheral part of the corneas were examined separately and compared to the central and peripheral parts of the controlateral corneas. The DNA content of the central portion of the wounded corneas progressively increased and reached after 60 days the same level as the corresponding portion of the controlateral corneas. The DNA contents of the peripheral portions of wounded and controlateral corneas are persistently higher than the DNA contents in the central portion. In peripheral portions of wounded corneas the DNA content is higher than in controlateral corneas and continues to increase steadily during the 60 days of experimentation. Cell density, as determined by morphometry, increased also during that period. The differences between the evolution of the DNA contents and cell density curves may be attributed to variations in cell sizes. The collagen content, estimated from hydroxyproline determinations remained lower in the wounded corneas as compared to the controlateral corneas, even 60 days after operation. This was true for the central as well as for the peripheral portions, suggesting a collagenolytic process as a result of wounding. This is confirmed by morphometric evaluation of fiber density.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

Electron microscopic study of aberrant lipogenesis in the cornea.

Aberrant lipogenesis is a protective reaction of cells by synthesis of triglycerides utilizing abnormally present oleic acid. In order to elucidate cytologic details of this phenomenon, a small amount of sodium oleate was injected into the corneal stroma of the rabbit, and the fat-forming cells were examined by electron microscopy. When tritiated oleate was used, the cytoplasm of the stroma cells in the vicinity of the injection site became diffusely radioactive immediately following the injection. The radioactivity was gradually concentrated in fat droplets. The cytoplasm of the corneal stroma, which contains relatively sparse micro-organelles, began to form small, slightly electron-dense spaces measuring 300-1000 A in diameter in the matrix, without correlation to any micro-organelle. These spaces never became radioactive. They may be the site of glyceride formation. These spaces became membrane-bound oil droplets measuring 500-100 A in diameter within 6 hours. The number and size of oil droplets increased for a few days and remained intracellular for a long period of time without causing any degenerative effect to the cell. The fatty substance had been proven to be mainly triglycerides in the earlier studies. Some longstanding fat droplets developed a few myelin figures. These lamellar membranes were heavily incorporated with the radioactive oleate.

Animals↗
PubMedDate not supplied

[Factor analysis, a measure of interrater reliability in single cases. Application to the AMDP Psychopathology Scale].

The reliability of a measure is a prerequisite for its validity. The measurement of the interrater reliability (IRR) of the 115-item AMDP System, filled out by 68 raters from several Centers for a single videotaped patient, raises two unusual aspects in IRR. First of all, a matrix of correlation coefficients between raters for such a number of individuals and items does not give a global visualization of differences in rating patterns. The authors apply the Q-technique of factor analysis (FA) or inverse FA in order to solve this problem. Second, the usual measures of IRR do not apply to single cases. In testing the adequacy of FA multivariate indexes as a measure of IRR (factor scores, Mahalanobis distances), the authors demonstrate a bias consisting of the influence of the mean item score on these indexes and they put forward an original modification of the classical FA program. They report a simulation of scores and the real patient CRO in order to demonstrate the adequacy of their modified FA as a measure of IRR in single cases.

Diagnosis, Differential↗
PubMed1995

[GeneBee-NET: An Internet based server for biopolymer structure analysis].

A network server providing biopolymer structure databank retrieval as well as some other biocomputing procedures for Internet users is described. Its basic procedures consist in looking for sequence and 3D homologies (similarities). Found homologies are used for constructing multiple alignment, for predicting RNA and protein secondary structures as well as for constructing phylogenetic trees. Alongside traditional methods of sequence homology retrieval, a "matrix-free" (correlation) method is proposed. A similar procedure is used to locate protein 3D similarities. For novel procedures algorithm ideas and their possible applications are discussed. The service ideology is based on the interaction of server and client programs. The client program (GeneBee for IBM PC) can be used to form queries to the server as well as to manipulate a treatment result. In the absence of the client program the interaction with the server can be in the text mode. The E-mail and WWW addresses for the server are as follows: SERVE/INDY.GENEBEE.MSU.SU and WWW.GENEBEE.MSU.SU.

Amino Acid Sequence↗
PubMed1996

[Meadow Maris: genes, surnames and migrations].

The matrices of genetic distances, calculated from the frequencies of surnames and the ABO, TF, GC, PI, HP, ACP1, and PGM1 genes, were compared with one another and with the migration matrix. The correlation coefficient between the "gene" and "surname" matrices was 0.71 +/- 0.35; other correlation coefficients were non-significant.

Adult↗