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PubMed2001

Simultaneous measurement of cerebral blood flow and mRNA signals: pixel-based inter-modality correlational analysis.

The analysis of pixel-based relationships between local cerebral blood flow (LCBF) and mRNA expression can reveal important insights into brain function. Traditionally, LCBF and in situ hybridization studies for genes of interest have been analyzed in separate series. To overcome this limitation and to increase the power of statistical analysis, this study focused on developing a double-label method to measure local cerebral blood flow (LCBF) and gene expressions simultaneously by means of a dual-autoradiography procedure. A 14C-iodoantipyrine autoradiographic LCBF study was first performed. Serial brain sections (12 in this study) were obtained at multiple coronal levels and were processed in the conventional manner to yield quantitative LCBF images. Two replicate sections at each bregma level were then used for in situ hybridization. To eliminate the 14C-iodoantipyrine from these sections, a chloroform-washout procedure was first performed. The sections were then processed for in situ hybridization autoradiography for the probes of interest. This method was tested in Wistar rats subjected to 12 min of global forebrain ischemia by two-vessel occlusion plus hypotension, followed by 2 or 6 h of reperfusion (n=4-6 per group). LCBF and in situ hybridization images for heat shock protein 70 (HSP70) were generated for each rat, aligned by disparity analysis, and analyzed on a pixel-by-pixel basis. This method yielded detailed inter-modality correlation between LCBF and HSP70 mRNA expressions. The advantages of this method include reducing the number of experimental animals by one-half; and providing accurate pixel-based correlations between different modalities in the same animals, thus enabling paired statistical analyses. This method can be extended to permit correlation of LCBF with the expression of multiple genes of interest.

Algorithms↗

PubMed1997

Assessment of hepatitis C virus quasispecies heterogeneity by gel shift analysis: correlation with response to interferon therapy.

Hepatitis C virus (HCV) quasispecies heterogeneity was assessed in pretreatment sera of 22 patients treated with interferon (IFN). Quasispecies heterogeneity was quantitated by analysis of 490 hypervariable region 1 (HVR1) clones using gel shift analysis (GSA), which allowed determination of two components of HCV quasispecies heterogeneity: genetic complexity (number of variants) and genetic diversity (mean genetic distance between variants). HCV genotype and pretreatment RNA titer were similar between responders (n = 12) and nonresponders (n = 10). GSA correlated well with nucleotide sequencing for estimating HCV genetic diversity (R = .952; P < .001). A positive correlation of .666 (P < .001) was observed between genetic diversity and complexity, suggesting that these components of quasispecies heterogeneity were related. However, while there were no significant differences in pretreatment complexity or genetic diversity among response groups, higher pretreatment genetic diversity was predictive of response failure (P = .041). Assessment of HVR1 heterogeneity by GSA revealed important relationships between quasispecies genetic diversity, complexity, and response to IFN therapy and suggested a need for analysis of other HCV genes.

Cloning, Molecular↗

PubMed1983

Cross-correlation analysis of geniculostriate neuronal relationships in cats.

The organization of geniculate inputs to a cat's visual cortical cell was studied by a cross-correlation technique. Simultaneous extracellular recordings were made in the lateral geniculate nucleus and in the striate cortex, and neuronal connectivity between a geniculate cell and a striate cell was examined by cross-correlograms of their impulse discharges under photic stimuli. Of 243 pairs of geniculate and striate cells with overlapping receptive fields, 82 showed positive correlations with short (0.9-2.7 ms) delay times. The delays in 65 of the 82 pairs were short enough to infer that the geniculate cell exerted monosynaptic excitatory action on the striate cell. Monosynaptic excitations were found in all types of striate cells. Those in cells with exclusively an on area or an off area (E-on/off cells) or in simple cells originated mostly from X geniculate cells; those in special-complex cells originated exclusively from Y geniculate cells; and those in standard-complex cells arose from both X and Y geniculate cells. The convergence number from geniculate cells to an E-on/off or simple striate cell was estimated as more than 10, since about 1/10 of the discharges from an E-on/off or simple cell in response to a moving stimulus was correlated with discharges from a geniculate cell. A larger convergence number (more than 30) was obtained for complex cells. Convergence from 2 to 5 geniculate cells was actually demonstrated in 17 of the 32 striate cells, each of which was tested in pair with 3-14 geniculate cells. The converging inputs thus observed included both X and Y geniculate cells in one E-on, one simple, and three standard-complex cells. They included both on-center and off-center geniculate cells in one simple, one special-complex, and five standard-complex cells. Under stimulation with a stationary light slit, the center fields but not the surround fields of geniculate cells were found to contribute to the receptive fields of the simple striate cells. However, the surround fields of geniculate cells contributed to the subliminal response areas flanking the central areas of E-on/off cells. The center fields of the geniculate cells also contributed to the central areas of the E-on/off cells. These observations suggest different models for simple cells and E-on/off cells as regards the organization of their geniculate inputs; simple cells may receive inputs from both on-center and off-center geniculate cells, but E-on/off cells receive inputs only from one or the other of them.

Animals↗

PubMed1983

The Luria-Nebraska Neuropsychological Battery and the Peabody Individual Achievement Test: a correlational analysis.

A group of 100 neurological, psychiatric, and normal subjects were administered both the Luria-Nebraska Neuropsychological Battery and the Peabody Individual Achievement Test. Correlations between LNNB subtests that tap skills necessary for academic achievement (Reading, Writing, Intellectual Processes, Arithmetic) and corresponding PIAT subtests were high. Correlations between LNNB Localization scales and PIAT scores were also high, with the left Parietal-Occipital Scale showing the highest correlation. Multiple regression analyses generated prediction equations for each PIAT subtest using the LNNB clinical scales.

Achievement↗

PubMed2003

Correlational analysis of MicroCog: Assessment of Cognitive Functioning with the Wechsler Adult Intelligence Scale-III for a clinical sample of veterans.

With rapid advances in technology and an emphasis in efficiency in psychological testing, there is a need to investigate the relation between a computerized cognitive examination and a traditional individually administered intelligence test. The current study provided correlations of intelligence scores from MicroCog: Assessment of Cognitive Functioning and intelligence scores from WAIS-III. MicroCog is a single computerized test measuring intelligence and the WAIS-III is a single traditionally administered test measuring intelligence. The study included 30 participants referred for psychological testing at a Veterans Medical Center in Tennessee as part of the standard intake process. Half of the participants were administered MicroCog first and half the WAIS-III first. Analysis indicated scores on the two tests were positively correlated. Index scores measuring similar constructs also were positively correlated. However, MicroCog was significantly more difficult than the WAIS-III in that scores were, on average, lower on MicroCog.

Adult↗

PubMed1998

Functional connectivity in depressive, obsessive-compulsive, and schizophrenic disorders: an explorative correlational analysis of regional cerebral metabolism.

In order to investigate the changes in functional relationships between brain regions in three psychiatric disorders, an exploratory statistical analysis of the regional cerebral metabolic rates for glucose (rCMRglu) obtained with positron emission tomography (PET) was performed. Correlations between various rCMRglu were computed in control, depressive, obsessive-compulsive, and schizophrenic groups to determine whether alterations of the correlation pattern were found in the psychiatric groups. The absence of correlation between left and right frontal lobes was common to the three psychiatric groups studied. Depressive patients recovered a better frontal interhemispheric coupling after successful treatment and the alterations in the depressed state also involved the relation between the right temporal cortex and the right thalamus. Obsessive-compulsive patients had not only lateral frontal dysfunction but also alterations in the functional relationships between cortex and thalami. In schizophrenic patients, the modifications of regional cerebral metabolic correlations involved both anterior and posterior cortical regions. Thus, although the relationship between left and right frontal lobes was altered in three psychiatric disorders, the pattern of functional connectivity between frontal regions, posterior cortical and subcortical regions differed depending on the diagnostic group.

Adult↗

PubMedDate not supplied

Correlation analysis of proprioceptive acuity in ipsilateral position-matching and velocity-discrimination.

In order to plan and control movements the central nervous system (CNS) needs to continuously keep track of the state of the musculoskeletal system. Therefore the CNS constantly uses sensory input from mechanoreceptors in muscles, joints and skin to update information about body configuration on different levels of the CNS. On the conscious level, such representations constitute proprioception. Different tests for assessment of proprioceptive acuity have been described. However, it is unclear if the proprioceptive acuity measurements in these tests correlate within subjects. By using both uni- and multivariate analysis we compared proprioceptive acuity in different variants of ipsilateral active and passive limb position-matching and ipsilateral passive limb movement velocity-discrimination in a group of healthy subjects. The analysis of the position-matching data revealed a higher acuity of matching for active movements in comparison to passive ones. The acuity of matching was negatively correlated to movement extent. There was a lack of correlation between proprioceptive acuity measurements in position-matching and velocity-discrimination.

Adult↗

PubMed1976

Photon correlation analysis of cytoplasmic streaming.

Laser light scattering has been used to investigate particle movements in a plant cell. Intensity autocorrelation functions are obtained by digital photon correlation of laser light scattered from cells of Nitella opaca both during cytoplasmic streaming and during the transitory cessation of streaming induced by electrical stimulation. The average velocity computed from the periodic oscillation in the intensity autocorrelation function during streaming corresponds to the velocity estimated using light microscopy. An estimate of the distribution of streaming velocities has been obtained from the decay in the amplitude of the envelope of the autocorrelation function derived from a streaming cell.

Cytoplasm↗

PubMed1994

Some small prostate cancers are nondiploid by nuclear image analysis: correlation of deoxyribonucleic acid ploidy status and pathological features.

The biological behavior of a prostate cancer can be predicted to some degree by the volume and extent (stage) of the tumor, and its histological grade. The deoxyribonucleic acid (DNA) ploidy status has been reported by some to be another independent prognostic factor for localized prostate cancer. We determined the DNA ploidy value of each individual focus of cancer in radical prostatectomy specimens using nuclear image analysis (CAS 200 system). Ploidy results were correlated with the volume, Gleason grade and zone of origin (transition zone or peripheral zone) of each tumor, and with the presence of extracapsular extension or seminal vesicle invasion. There were 141 separate cancers in 68 patients (mean 2.1 per prostate): 9 clinical stage A1, 22 stage A2, 23 stage B1 and 14 stage B2. DNA ploidy correlated significantly (p < 0.0001) with volume, grade, extraprostatic spread and zone of origin. Remarkably, some small cancers (1 cc or less) were nondiploid (3 as small as 0.03 cc). Overall, 15% of cancers 0.01 to 0.1 cc and 31% of those 0.11 to 1.0 cc in volume were nondiploid. Of 101 cancers confined to the prostate 76% were diploid, compared to only 13% of those with extraprostatic spread. Most cancers of transition zone origin (86%) were diploid, compared to only 49% of peripheral zone cancers, and ploidy and volume relationships were significantly different for peripheral zone cancers compared to transition zone cancers. All small nondiploid cancers arose in the peripheral zone, while in the transition zone the smallest nondiploid cancer was 1.17 cc. We conclude that prostate cancers that are nondiploid are highly likely to have adverse pathological features. Some small prostate cancers contain a nondiploid cell population and these cancers arise predominantly within the peripheral zone of the prostate. Ploidy and volume relationships provide further support for the hypothesis that there is a difference in malignant potential between cancers of peripheral zone and transition zone origin.

Cell Nucleus↗

PubMed1995

Characterization of simple and complex hepatitis C virus quasispecies by heteroduplex gel shift analysis: correlation with nucleotide sequencing.

In infected humans, hepatitis C virus (HCV) exists as a quasispecies typically characterized by multiple nucleotide substitutions within the second envelope gene hypervariable region 1 (HVR1). In the current study, we used heteroduplex gel shift analysis (GSA) of HVR1 sequences amplified directly from patients' sera to define two patterns of HCV quasispecies: (i) simple quasispecies, which gave a mostly homogeneous gel shift profile with a single predominant band and (ii) complex quasispecies, which gave a gel shift profile with multiple bands. Recombinant HVR1 libraries were generated from two patients with complex HCV quasispecies (cases 1 and 2) and two patients with simple HCV quasispecies (cases 3 and 4), and 129 individual clones were analysed by either GSA, nucleotide sequencing or both techniques. In case 1 we identified a highly complex HCV quasispecies with 11 distinct HVR1 variants differing by 1-51 nucleotide changes. We found a general but not absolute correlation between GSA pattern and the number or position of nucleotide changes within HVR1. In case 2, the complex HCV quasispecies consisted of three distinct major variants; GSA of individual HVR1 clones allowed us to reconstruct the complex quasispecies pattern in vitro. In case 3, the simple quasispecies comprised 66% homogeneous clones and 33% unique minor variants differing by 1-3 nucleotides from the consensus sequence. In case 4, the simple quasispecies was 84% homogeneous, but six unique major shift variants were identified among 31 clones by GSA. In summary, HCV quasispecies can be characterized based on GSA profiles following direct PCR amplification of HVR1 sequences from patients' serum; the GSA profiles approximate the clonal population of HCV as determined by clonal analysis. GSA of HVR1 clones showed a strong correlation with nucleotide sequencing.

Base Sequence↗

PubMed1991

Uteroplacental Doppler flow velocity waveform analysis correlates poorly with glycemic control in diabetic pregnant women.

We examined 65 pregnant women with gestational (n = 31) and insulin dependent (n = 34) diabetes mellitus in order to evaluate the clinical usefulness of Doppler flow velocity waveform analysis in these pregnancies. Umbilical and uterine artery flow velocity waveforms were obtained during the third trimester with a continuous wave Doppler device. Quality of maternal glycemic control was evaluated by hemoglobin (Hb) A1 measurements at the time of delivery in 61 patients and by mean capillary blood sugars during the third trimester of pregnancy in four patients. There was no difference in various clinical and Doppler parameters between patients with good glycemic control and those with poor control. In contrast, the same clinical and Doppler parameters were significantly different in patients with preeclampsia than in those without preeclampsia, regardless of glycemic control. There was a poor positive linear correlation (r = 0.30, p less than 0.02) between maternal HbA1 and umbilical artery flow velocity waveforms (systolic/diastolic ratio). Proteinuria correlated better with umbilical artery systolic/diastolic ratio (r = 0.49, p less than 0.001). We conclude that Doppler flow velocity waveform analysis may be clinically useful only in diabetic pregnancies complicated by preeclampsia.

Adult↗

PubMed1986

Correlational analysis of central noradrenergic neuronal activity and sympathetic tone in behaving cats.

The activity of the noradrenergic (NA) neurons of the feline locus coeruleus complex (LCx) were correlated with changes in peripheral sympathetic tone in behaving cats. LCx NA neurons exhibit stereotypical changes in discharge rate across behavioral states, falling virtually silent during paradoxical sleep (PS). Simultaneous recordings from LCx NA neurons and the cervical sympathetic trunk demonstrated a tonic reduction in nerve activity during PS as well. LCx NA neurons were also found to fall silent during induction of the scruff immobility reflex and significant pupillary miosis was seen during this behavior as well. These data support the hypothesis that NA neurons in the brain are a central analogue of the peripheral sympathetic system and demonstrate that the two systems operate in an integrated fashion in the behaving cat.

Animals↗

PubMed1985

Longitudinal correlation analysis of standing height and intelligence.

Intercorrelations of 10 successive years of measurement of height and intelligence are presented for separate samples of girls and boys. These correlations are based on data originally gathered and published by Dearborn, Rothney, and Shuttleworth as the Harvard Growth Study. Sample size varies from correlation to correlation, but most of those for girls are based on samples of 500-700 and those for boys on samples of 400-500. The intercorrelations of each of the 2 variables over 10 occasions do not differ appreciably by sex, but there are significant differences between the sexes in the cross-correlations. For the sample of girls there is clear evidence that individual differences in height at 8 and 9 anticipate later individual differences in intelligence. Correlations of early height with intelligence at 11 and 12 are especially high (.40). There is little evidence for similar anticipation of intelligence by height for boys. Correlates for both height and intelligence are found in socioeconomic status, ethnicity, and age of first menstruation for girls. Only the last of these contributes to the explanation of the changes in the cross-correlations with age. Analyses of sitting-height correlations with intelligence indicate that length of the long bones of the legs is also related to the observed pattern of correlations.

Adolescent↗

PubMed1994

Personal incentives for exercise and body esteem: a canonical correlation analysis.

Two hundred twelve women and 93 men enrolled in physical education courses were administered the Personal Incentives for Exercise Questionnaire and the Body Esteem Scale. Canonical correlation was conducted. For women, it was determined that personal incentives for exercise have modest predictive power for the weight concern and physical conditioning dimensions of body esteem and very little predictive power for the sexual attractiveness dimension; the body esteem variates have slight predictive power for the competition and weight management dimensions of investment in exercise. For men, it was determined that personal incentives for exercise have modest predictive power for the physical conditioning dimension of body esteem, slight predictive power for physical attractiveness, and none for upper body strength; the body esteem variate has modest predictive power for the weight management dimension of incentives for exercise and slight predictive power for appearance and affiliation.

Adult↗

PubMed1977

[Clinical-correlation analysis in lesions of the temporal lobe].

The report deals with the role of nonspecific and specific brain systems in the clinical picture of brain lesions of the temporal lobe. In this connection special attention was drawn to the correlation between the etiology of the disease, the model of epileptical seizures and the symptoms of the disease, as well as to the clinical traits connected with hemisphere functional asymmetry. The author examined 164 patients from 20-60 years. The clinical data, clinico-psychological studies and the results of laboratory methods were processed for a clinicocorrelational analysis. Expressed vegetative, endocrine, emotional and mnestic disturbances of sleep and wakefulness are related with dysfunctions of the nonspecific brain systems and correlate with a certain model of the seizure, etiology and side of the lesion.

Adult↗

PubMed1997

Audiological correlates of speech understanding deficits in elderly listeners with mild-to-moderate hearing loss. II. Correlation analysis.

OBJECTIVE: The study was conducted to determine the relationship between measures of auditory performance in elderly individuals. Specifically, its goal was to uncover a set of measures correlated with the set of measures of speech understanding under specific conditions of interference to gain a better understanding of decline of the "cocktail party effect" in aging. DESIGN: Audiological status and auditory performance of a group of elderly (60- to 81-yr-old) individuals were determined through a test battery. When present, the hearing loss of elderly subjects was symmetrical in the two ears and, at most, moderate. The battery included tests of speech intelligibility on the word and sentence levels, with and without the presence of interfering speech. In addition pure-tone and speech reception thresholds, perception of spectrally or temporally distorted speech and auditory resolution of frequency, time, and space were tested. Two tests received special consideration: the Speech Perception In Noise Test and the Modified Rhyme Reverberation Test. RESULTS: Results indicated that, despite the nearly normal hearing levels that characterized much of the subject group, auditory sensitivity measures showed persistent correlation to all other measures, with the exception of auditory resolution regarding frequency, time, and space. As a set, sensitivity measures accounted for more than 85% of the variance. When auditory sensitivity was controlled for, other factors underlying speech processing in the presence of interfering stimuli were uncovered, factors most likely related to the ability to perceptually segregate one speech signal from another. CONCLUSIONS: The findings suggest that, to determine the relationship between audiological/auditory test results of an elderly population, it is important to remove the effects of hearing loss through appropriate statistical methods.

Aged↗

PubMed2002

[Correlative analysis of the psychological disorder with ability to resume work in burn patients].

OBJECTIVE: To analyze the influencing factors of the psychological disorder in burn patients and its correlation with the ability to resume work. METHODS: Five hundred and sixty burn patients aged 7 approximately 76 years old were enrolled in the study. The patients' psychological disorder was evaluated by self-rating anxiety scale (SAS), self-rating depression scale (SDS), and symptom check list-90 (SCL-90). Global assessment scale (GAS) was employed to detect the severity of the psychological disorder and the social function during 1 month to 2 years of the convalescent stage of burn patients. Discharged burn patients were followed up by questionnaire and telephone for their ability to resume work. RESULTS: Anxiety and depression in patients with severe burn or facial burn occurred earlier and severer and the patients worried about the possibility to resume their work, the maintainance of family relation, and the ability to join the society, All these problems aggravated their psychological disorder. After psychotherapy, the disorders were obviously alleviated (P < 0.05). CONCLUSION: Severe psychological disorders might delay the time of patients'ability to resume their previous work.

Adolescent↗

PubMed2006

[A research of correlative analysis between EEG signal and the input-signal of the acupoints].

In this paper, different acupoints are stimulated by using pulse stimulating signals with different frequency. The correlation between input signal from acupoints and output signal from brain band is studied. A method to optimize input of acupoints is obtained by an experiment system. And the dynamic connection between meridian and brain band is identified. Experiment has shown that there exists maximal correlation between the signal of 30 Hz intermittent pulse stimulation and the induced cerebral alpha band. And the 30 Hz intermittent pulse stimulation can induce more beneficial cerebral a band.

Acupuncture Points↗