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PubMed2004

Reduced dopamine D3 receptor expression in blood lymphocytes of smokers is negatively correlated with daily number of smoked cigarettes: a peripheral correlate of dopaminergic alterations in smokers.

The mesolimbic dopaminergic system is known to mediate rewarding effects of nicotine administration, and dysfunctions of this system may underlie failure to stop cigarette smoking. Expression of dopamine receptors in peripheral blood lymphocytes (PBLs) has been indicated as a peripheral correlate of brain status. Dopamine receptor D(3) (DRD3) and D(4) (DRD4) mRNA expression in PBLs was measured by real-time polymerase chain reaction in smokers (n=26) and former smokers (n=14), compared with nonsmoking control subjects (n=35). A significant (p=.032, Bonferroni corrected) 30% reduction of DRD3 mRNA expression in PBLs was found in smokers but not former smokers in comparison with controls. DRD3 mRNA expression in PBLs in smokers but not former smokers was negatively correlated with daily number of cigarettes consumed (Pearson correlation coefficient r=-.54, p=.005). These data suggest a selective inhibiting effect of smoking on DRD3 mRNA expression and, with the known involvement of DRD3 in reward mediation, indicates a vicious-cycle explanation for the motivation for continued smoking.

Actins↗

PubMed1994

A comprehensive study of physical parameters, biomechanical properties, and statistical correlations of iliac crest bone wedges used in spinal fusion surgery. I. Physical parameters and their correlations.

Iliac crest bone wedges are commonly used in spinal fusion procedures and must be capable of withstanding considerable mechanical stress during the healing process. The variability of "quality" of bone materials used in the production of bone wedges suggests that some bone materials may not be suitable for use in vertebral fusion procedures and some quantifiable means of predicting the suitability of bone wedges would be desirable. A total of 250 iliac crest wedges were used in this study. Physical parameters of iliac crest wedges, such as total cross-sectional area, cancellous cross-sectional area, cortical cross-sectional area, percentage of cortical cross-sectional area, "width," and apparent density were determined. The statistical correlations among physical parameters were investigated. These correlations revealed that the relative percentage of cortical and cancellous bone remained fairly constant at 41% and 59%, respectively, regardless of total cross-sectional area of a wedge, that apparent density did not appreciably change with donor age, and that ash (inorganic) and organic content (weight) correlated well with the apparent density.

Aging↗

PubMed2005

Probing pair-correlated fermionic atoms through correlations in atom shot noise.

Pair-correlated fermionic atoms are created through dissociation of weakly bound molecules near a magnetic-field Feshbach resonance. We show that correlations between atoms in different spin states can be detected using the atom shot noise in absorption images. Furthermore, using time-of-flight imaging we have observed atom pair correlations in momentum space.

Journal Article↗

PubMed1999

The immunoglobulin (IgG) antibody response to OspA and OspB correlates with severe and prolonged Lyme arthritis and the IgG response to P35 correlates with mild and brief arthritis.

In an effort to implicate immune responses to specific Borrelia burgdorferi proteins that may have a role in chronic Lyme arthritis, we studied the natural history of the antibody response to B. burgdorferi in serial serum samples from 25 patients monitored throughout the course of Lyme disease. In these patients, the immunoglobulin G (IgM) and IgG antibody responses to 10 recombinant B. burgdorferi proteins, determined during early infection, early arthritis, and maximal arthritis, were correlated with the severity and duration of maximal arthritis. The earliest responses were usually to outer surface protein C (OspC), P35, P37, and P41; reactivity with OspE, OspF, P39, and P93 often developed weeks later; and months to years later, 64% of patients had responses to OspA and OspB. During early infection and early arthritis, the levels of IgG antibody to P35 correlated inversely with the subsequent severity or duration of maximal arthritis. In contrast, during periods of maximal arthritis, the levels of IgG antibody to OspA and OspB, especially to a C-terminal epitope of OspA, correlated directly with the severity and duration of arthritis. Thus, the higher the IgG antibody response to P35 earlier in the infection, the milder and briefer the subsequent arthritis, whereas during maximal arthritis, the higher the IgG response to OspA and OspB, the more severe and prolonged the arthritis.

Adolescent↗

PubMed1984

Blood pressure and chemistry: some correlations and apparent correlations.

The reported correlation between plasma calcium and blood pressure has been investigated in 412 young men and women. In this sample, it seemed to be due to a stronger correlation between blood pressure and plasma albumin. Blood pressures were also significantly correlated with plasma high-density lipoprotein in men and with plasma uric acid in women.

Adolescent↗

PubMed2004

Optical correlation of spatial-frequency-shifted images in a photorefractive BSO correlator.

The optical cross correlation of an image with another image that was spatial-frequency shifted in one dimension was demonstrated in a photorefractive VanderLugt correlator. The first image was stored as a Fourier-transform hologram in a photorefractive Bi12SiO20 crystal (BSO) and was successively correlated with different spatial-frequency-shifted versions of a second image. We implemented the spatial-frequency shift by rotating a galvanometer mirror in an image plane, causing the Fourier transform to be shifted laterally in the BSO. We verified that the resulting operation in the BSO was an accurate complex multiplication of the shifted and the stored Fourier transforms. As many as 20 successive readouts were conducted without measurable erasure of the stored hologram. The dynamic range, saturation behavior, and other performance parameters were measured and are discussed.

Journal Article↗

PubMedDate not supplied

Protoporphyrin IX level correlates with number of mitochondria, but increase in production correlates with tumor cell size.

Protoporphyrin IX (PpIX) is produced in cells via the heme synthesis pathway, from the substrate aminolevulinic acid (ALA), and can be used for tumor detection, monitoring or photodynamic therapy. PpIX production varies considerably between tumor cell types, and determining the cell types and methods to optimize production is a central issue in properly utilizing this drug. A panel of eight cancer cell types was examined for PpIX production capacity, including breast, prostate, and brain cancer tumors, and the production varied up to 10-fold among cell types. A positive correlation was seen between mitochondrial content and naturally occurring PpIX prior to ALA administration, but mitochondrial content did not correlate to the yield of PpIX resulting from the addition of ALA. Interestingly, total cell size was positively correlated to the yield of PpIX from ALA administration. Addition of an iron chelator, 1,2-dimethyl-3-hydroxy-4-pyridone (L1) in combination with ALA allows the final step in the heme synthesis pathway, conversion of PpIX to heme, to be delayed, thereby further increasing the yield of PpIX. Those cell types that had the lowest ALA to PpIX production without L1 showed the largest percentage increase in production with L1. The study indicates that use of L1 in tumors with a lower innate production of PpIX with ALA alone may be the most productive approach to this combined delivery.

Aminolevulinic Acid↗

PubMed2000

Wavelength-resolved fluorescence emission of proteins using the synchrotron radiation as pulsed-light source: cross-correlations between lifetimes, rotational correlation times and tryptophan heterogeneity in FKBP59 immunophilin.

The time-resolved fluorescence intensity and anisotropy decays of the immunophilin domain of FKBP59 (FKBP59-I)--a protein containing two tryptophan residues (the W89, buried in a hydrophobic pocket and the W59, water exposed)--were studied using the time-correlated single photon counting (TCSPC) technique. The synchrotron radiation machine Super-ACO (Orsay, France) was used as a pulsed light source (approximately 8MHz). A mainly dual and discrete excited state lifetime distribution was previously evidenced (Rouvière et al., 1997). The lifetime heterogeneity has been suggested to be relevant to the topological tryptophan heterogeneity. Indeed, taking into account the spectroscopic properties of the single tryptophan residue of the immunophilin FKBP12, a highly homologous protein containing a single tryptophan residue, the short- and the long-lived lifetime species were assumed to be related to the solvent-buried and to the solvent-exposed fluorescent residues, respectively. We definitely demonstrate this point by describing the dynamical properties of each tryptophan residue of the FKBP59-I as a function of the emission wavelength. The data of the polarized components of the fluorescence emission were analyzed by the Maximum Entropy Method using a one-dimensional model (each excited-state lifetime tau being associated with each rotational correlation time theta) and a two-dimensional model (without any a priori association constraint between the tau's and the theta's). The two dimensional analysis of the polarized fluorescence intensity decays by MEM show the existence of a correlation between fast picosecond dynamics of the indole ring with the shortest-lived and blue emitting species. Conversely, the long-lived and red emitting population is mainly associated to the Brownian motion of the protein. A protein flexibility of the region located around the W59 residue, but slightly contributing to the light depolarization process, is also evidenced and can be specifically attributed to the red emitting population.

Fluorescence Polarization↗

PubMed2001

[Following 90 patients with antiphospholipid syndrome with antibody titers and correlations with clinical manifestations: symptoms of the disease, a new antibody and correlations with clinical manifestations in the Israeli population].

UNLABELLED: The antiphospholipid syndrome (APS) is defined by the presence of antiphospholipid antibodies (aPLs) with venous or arterial thrombosis, recurrent pregnancy loss or thrombocytopenia. The syndrome can be either primary or secondary to an underlying condition, most commonly systemic lupus erythematosus (SLE). The purpose of the study was to review the manifestations of the APS in Israeli patients and to investigate the difference between patients with primary or secondary syndrome. Analysis of the correlation between the manifestations of the disease and the antibody titers [LA (lupus anticoagulant), IgG aCL (anticardiolipin), IgM aCL] was also performed. In the study there were 90 patients with APS in the Sheba Medical Center. The clinical findings for all patients were recorded according to established protocol. RESULTS: Arterial thrombotic events were present in 51.1% of the patients; cerebral ischemic attacks were the most frequent arterial events. Venous thrombotic events were present in 45.6% patients; deep venous thrombosis was the most frequent venous event. Obstetric complications were found in 37.3% of patients; the most frequent complication was abortions. The clinical findings of patients with primary or secondary syndrome were similar. Patients with APS associated with lupus had a high prevalence of hemolytic anemia (28.6% v 3.3%; P = 0.001), and ANA (antinuclear antibody) (75% v 12.9%; P = 0.0001). There was no correlation between the antibody titers (LA, IgG aCL, IgM aCL) and clinical manifestations. The patients received anticoagulant treatment and antiaggregant drugs to prevent recurrence of symptoms. Clinical manifestations in Israeli patients did not differ from those in non-Israeli patients. CONCLUSIONS: Venous or arterial thrombosis and obstetric complications are the most frequent clinical findings in APS. There was no different in clinical manifestations between primary and secondary syndrome. The findings of autoimmune hemolytic anemia and ANA were more frequent in patients with secondary APS. There was no correlation between antiphospholipid antibody titers and manifestations of disease. Overall, the patients require therapy with anticoagulant treatment and antiaggregant drugs. The clinical manifestations were similar in Israeli and non-Israeli patients.

Abortion, Habitual↗

PubMed1999

[Study on correlation between in vivo and in vitro tests of biomaterials--correlation between leukocyte chemotaxis test and muscular implant test in rabbits].

The purpose of this study was to investigate the correlation between the results of in vivo and in vitro tests of biomaterials. With muscular implant test and leukocyte chemotaxis test, the levels of tissue toxicity of seven biomaterials were evaluated. The samples with high-level toxicity showed weak leukocyte chemotaxis, which would influence the anti-inflammatory reaction to foreign bodies. By the method of Spearman rank correlation, the coefficient was between 0.89286-0.98198 indicating that the correlation of the two tests is excellent.

Animals↗

PubMed2006

E-cadherin status in breast cancer correlates with histologic type but does not correlate with established prognostic parameters.

Our objective was to assess the loss of E-cadherin (EC) as a diagnostic marker or a predictor of prognosis. We stained 276 breast carcinomas with monoclonal antibodies to EC (invasive lobular carcinomas [ILC] and variants, 59; invasive ductal carcinoma and ductal special types [IDC], 204; tubulolobular carcinoma [TLC], 4; and invasive carcinoma [IC], uncertain whether lobular or ductal type, 9). The results were as follows: EC+IDCs, 99.5%; EC-ILCs, 90%; EC+ILCs, 10%; EC+pleomorphic ILCs, 20%; EC-ICs, 44%. All 4 TLCs showed positive tubules while cords were negative. Statistically a correlation of EC loss with a positive diagnosis of ILC was found but there was no correlation with any prognostic tumor variables. A negative EC stain confirms the diagnosis of ILC (specificity, 97.7%; negative predictive value, 96.8%; sensitivity, 88.1%; positive predictive value, 91.2%). EC is helpful in classifying cases with indeterminate histologic features. EC loss is uncommon in nonlobular carcinomas with no correlation to currently established prognostic variables.

Adenocarcinoma↗

PubMed1988

[Correlation between selenium levels in the human body and lung cancer. II. Multi-statistical analysis of the correlation between selenium levels in the blood, hair, lung and lung cancer].

18 factors, including possible lung cancer-causing factors and body selenium (Se) levels, were analyzed by computer-based multiple stepwise regression and main component analysis. 1. The results indicated that Se levels in blood, hair and lung had correlation with lung cancer to some extent. 2. The correlation of blood and lung Se was the most significant one, the significance of which was only second to age and smoking habits. The standardized regression and factor load coefficients showed a negative correlation with blood Se level and a positive one with lung Se level, which corresponded with the results obtained by the single factor analysis.

Factor Analysis, Statistical↗

PubMed1996

Cervical biopsy-cytology correlation. A College of American Pathologists Q-Probes study of 22 439 correlations in 348 laboratories.

OBJECTIVE: To study the diagnostic correlation between cervical cytology specimens and corresponding surgical biopsies. DESIGN AND SETTING: College of American Pathologists Q-Probes laboratory quality improvement study in 348 laboratories. MAIN OUTCOME MEASURES: Sensitivity, specificity, and positive predictive value of cervicovaginal cytology diagnosis. RESULTS: Statistical analysis of 22 439 paired cervicovaginal cytology--cervical biopsy specimens reveals a sensitivity of 89.4%, specificity of 64.8%, and predictive value of a positive cytology of 88.9%. The majority of discrepancies were attributed to cytology or biopsy sampling errors. Routinely providing the patient's recent cervical cytology report to the surgical pathologist at the time the biopsy was examined resulted in improved sensitivity. Correlations for cytology specimens obtained at the time of biopsy revealed lower sensitivity and higher specificity than for those obtained at a time prior to the biopsy. CONCLUSIONS: We have defined current statistical expectations for cervical cytology-biopsy correlation, reasons for noncorrelation, and have provided recommendations for quality improvement.

Biopsy↗

PubMed2006

Fluorescence lifetime images and correlation spectra obtained by multidimensional time-correlated single photon counting.

Multidimensional time-correlated single photon counting (TCSPC) is based on the excitation of the sample by a high-repetition rate laser and the detection of single photons of the fluorescence signal in several detection channels. Each photon is characterized by its arrival time in the laser period, its detection channel number, and several additional variables such as the coordinates of an image area, or the time from the start of the experiment. Combined with a confocal or two-photon laser scanning microscope and a pulsed laser, multidimensional TCSPC makes a fluorescence lifetime technique with multiwavelength capability, near-ideal counting efficiency, and the capability to resolve multiexponential decay functions. We show that the same technique and the same hardware can be used for precision fluorescence decay analysis and fluorescence correlation spectroscopy (FCS) in selected spots of a sample.

Cell Line↗

PubMed1992

Correlated binomial variates: properties of estimator of intraclass correlation and its effect on sample size calculation.

In group randomized studies, the sample size calculations are complicated by within group (worksite, community, etc.) correlation. We compare by simulation the moment method and the more standard ANOVA method of estimating the intraclass correlation. We find the former is less biased for a small to moderate number of clusters but the difference disappears when the appropriate degree of freedom is used for the ANOVA estimator. We propose a simulation approach for sample size determination and illustrate it with an example.

Analysis of Variance↗

PubMed1997

Activity of vesicular stomatitis virus M protein mutants in cell rounding is correlated with the ability to inhibit host gene expression and is not correlated with virus assembly function.

In addition to its role in virus assembly, the matrix (M) protein of vesicular stomatitis virus (VSV) is involved in virus-induced cell rounding and inhibition of host-directed gene expression. Previous experiments have shown that two M protein mutants genetically dissociate the ability of M protein to inhibit host-directed gene expression from its function in virus assembly. M protein from tsO82 virus is fully functional in virus assembly but defective in the inhibition of host-directed gene expression, while the MN1 deletion mutant, which lacks amino acids 4-21, inhibits host-directed gene expression but cannot function in virus assembly. Experiments presented here compared cell rounding induced by these two mutant M proteins to that of wt M protein. BHK cells were transfected with M protein mRNA transcribed in vitro, and the extent of cell rounding was evaluated at 24 hr posttransfection. The MN1 protein was nearly as effective as wt M protein in the induction of cell rounding, while tsO82 M protein expressed from transfected RNA was not able to induce cell rounding above that observed in negative controls without M protein, although it did cause BHK cells to have a less elongated shape. These results indicate that the ability of MN1 and tsO82 M proteins to induce cell rounding is not correlated with their virus assembly function. Instead the cell rounding activity of these mutants is correlated with their ability to inhibit host-directed gene expression. Previous data suggesting that these two cytopathic activities could be dissociated can be readily accounted for by quantitative differences in M protein expression required. Infection of either BHK cells or L cells with tsO82 virus induced cell rounding, although cell rounding was delayed relative to that following infection with wt VSV, suggesting that tsO82 M protein retains some cytopathic activity. The distribution of actin, vimentin, and tubulin in transfected cells was determined by fluorescence microscopy. In cells transfected with tsO82 M mRNA, these cytoskeletal elements were indistinguishable from those of negative control transfected cells. In cells rounded as a result of transfection with wt M or MN1 mRNA, actin-containing filaments were reorganized into a thick perinuclear ring but were not depolymerized. In contrast, tubulin and vimentin appeared to be diffusely distributed throughout the cytoplasm of rounded cells. These results support the idea that cell rounding induced by M protein results from the depolymerization of microtubules and/or intermediate filaments.

Animals↗

PubMed1989

Sequential 1H and 13C resonance assignments for an octa- and decasaccharide of the N-acetyllactosamine type by multiple-step relayed correlation and heteronuclear correlation nuclear magnetic resonance.

400 MHz 1H-NMR and 100 MHz 13C-NMR spectra of a neutral octasaccharide and of a disialyldecasaccharide of the N-acetyllactosamine type were studied. The resonance assignments were made by combining multiple-relayed coherence-transfer chemical-shift-correlated spectroscopy (multiple-RELAY-COSY) and 1H/13C-shift correlated 2D experiments. The complete analysis of the 1H and 13C spectra was performed.

Amino Sugars↗

PubMed1981

An apparent correlation between the inhibition of induced ornithine decarboxylase activity by gamma radiation and the capacity for DNA repair synthesis in normal and ataxia telangiectasia human fibroblasts: no correlation with cell survival.

Exposure of normal human fibroblasts (F107) in stationary phase to gamma radiation inhibited the appearance of induced ornithine decarboxylase (ODC) activity. Skin fibroblasts derived from two ataxia telangiectasia (AT) patients (F184 and F182) displayed a similar response. The level of DNA repair synthesis was also similar in the three cell strains. Fibroblasts from another apparently normal donor (F196) were very sensitive to inhibition of induced ODC activity by gamma radiation and were also deficient in radiation-induced DNA repair synthesis. However, the two strains derived from normal donors displayed the same degree of cellular sensitivity towards X-rays, whereas the two AT strains showed the typical hypersensitivity to the cytotoxic effect of X-irradiation. The results suggest a possible correlation between the inhibition of induced ODC activity by gamma radiation and the extent of DNA repair synthesis at high radiation doses, but there is no correlation between these two parameters and cellular survival at low radiation doses.

Ataxia Telangiectasia↗