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Intravitreal levels of vascular endothelial growth factor and interleukin-6 are correlated with macular edema in branch retinal vein occlusion.

BACKGROUND: To investigate whether vascular endothelial growth factor (VEGF) or interleukin-6 (IL-6) contributes to the pathogenesis of macular edema in eyes with branch retinal vein occlusion (BRVO), the correlations between these factors were investigated. METHODS: We studied 25 patients suffering from macular edema with BRVO and 14 patients with nonischemic ocular disease (control group). The degree of retinal ischemia was evaluated in terms of the area of capillary nonperfusion using Scion Images, and the severity of macular edema was examined using optical coherence tomography. Vitreous fluid samples were obtained at the time of vitreoretinal surgery, and VEGF and IL-6 levels in the vitreous fluid and plasma were determined by means of enzyme-linked immunosorbent assays. RESULTS: Vitreous fluid levels of VEGF and IL-6 were significantly elevated in patients with BRVO compared with control patients (P = 0.0011 and P < 0.0001, respectively). Also, the vitreous level of VEGF was significantly correlated with that of IL-6 (P = 0.0012), and vitreous levels of VEGF and IL-6 were correlated with the size of the BRVO nonperfusion area (P < 0.0001 and P = 0.0033, respectively). Furthermore, vitreous levels of VEGF and IL-6 were correlated with the severity of macular edema (P = 0.0008 and P = 0.0191, respectively) and the severity of macular edema of BRVO was significantly correlated with the size of the BRVO nonperfusion area (P=0.0044). CONCLUSIONS: The levels of VEGF and IL-6 are increased in patients with macular edema with BRVO and are significantly correlated with the size of the nonperfusion area and the severity of macular edema. Therefore, they may play a role in macular edema with BRVO.

Enzyme-Linked Immunosorbent Assay↗

Ophthalmological findings in patients with spinocerebellar ataxia type 1 are not correlated with neurological anticipation.

BACKGROUND: Optic atrophy, attenuation of the oscillatory potentials (OPs) of the electroretinogram (ERG), and enlargement of corneal endothelial cells, have been reported in patients with spinocerebellar ataxia type 1 (SCA1). These patients have a trinucleotide repeat expansion in the SCA1 gene and show neurological anticipation. The purpose of this study was to determine whether the ophthalmological findings are correlated with the neurological disorders, and whether ophthalmological anticipation is present in patients with SCA1. METHODS: The visual acuity, ERGs, and corneal endothelial cell density were examined in 14 patients whose DNA analysis revealed an expanded trinucleotide repeat in an allele of the SCA1 gene. The results of the tests were compared with the trinucleotide repeat number and the duration of the neuronal disease. RESULTS: The neurological disorders in the patients showed anticipation. The negative correlation between the trinucleotide repeat number and the neurological disorder was statistically significant (P<0.0001). However, the correlations between trinucleotide repeat number and visual acuity, amplitude of OPs, and corneal endothelial cell density were not significant. Statistically significant correlations were found between the duration of the neuronal disease and the visual acuity, OPs, and corneal endothelial cell density (P<0.0001, P=0.0004, and P<0.0001, respectively). The ophthalmological disorders were prominent in patients who had neuronal disease for more than 10 years. CONCLUSION: Unlike the neurological findings, the ophthalmological disorders in patients with SCA1 were not correlated with the trinucleotide repeat number of the SCA1 gene. The ophthalmological findings were most highly correlated with the duration of the neuronal disease.

Adult↗

Correlation between urine and blood concentrations, and dietary intake of cadmium and lead among women in the general population of Japan.

OBJECTIVE: To examine whether lead (Pb) in urine and cadmium (Cd) in blood, especially the former, can be used as markers of environmental exposure of general populations to these metals. METHODS: Between 1991 and 1998, spot urine and peripheral blood samples, together with 24 h duplicates of food intake were collected from 607 non-smoking adult women in 30 survey sites (SS) in seven administrative regions all over Japan. Urine, blood and food duplicate samples were analyzed by inductively-coupled plasma spectrometry, for Cd and Pb in urine (Cd-U and Pb-U), in blood (Cd-B and Pb-B) and in food duplicates (Cd-F and Pb-F). Correlation between the measurements was examined by regression analysis. RESULTS: The Cd-B correlated closely with Cd-U, and both Cd-B and Cd-U with Cd-F, on an individual basis (n = 607), on an SS basis (n = 30) and on a regional basis (n = 7). The Pb-U however did not correlate with Pb-B on a regional basis although they correlated with each other when analyzed on an individual as well as SS basis. Moreover, the correlation coefficients between Pb-U and Pb-B were much smaller than those between Cd-U and Cd-B. Neither Pb-U nor Pb-B showed significant correlation with Pb-F on any levels of statistical analysis. CONCLUSIONS: Both Cd-B and Cd-U can be employed as biomarkers of environmental Cd exposure. The reliability of Pb-U for use in place of Pb-B appeared to be small.

Adult↗

Correlating motor performance with surgical error in laparoscopic cholecystectomy.

BACKGROUND: Analysis of motor performance in minimally invasive surgery (MIS) is a new field with applications in surgical training, surgical simulators, and robotics. Force/torque and derivatives of tool tip position (velocity, acceleration, and jerk) are examples of measures of motor performance (MMPs). Few studies have measured MMPs or have correlated MMPs with surgical performance during MIS on humans. The objectives of this study were to determine the feasibility of a novel multimodal system to quantify MMPs in laparoscopic cholecystectomy and to attempt to correlate MMPs with the magnitude of error as a measure of surgical performance. METHODS: Novice and expert surgeons performed laparoscopic cholecystectomies in two groups of three patients each. MMPs were obtained using a combination of optical and electromagnetic tool tip tracking and a force/torque sensor on a modified Maryland dissector. Error scores for laparoscopic cholecystectomy were calculated using a previously validated system. Novice and expert measurements were compared, and correlations were made between error scores and MMPs. RESULTS: Error scores were similar between novices and experts. Novice surgeons had a significantly greater mean velocity (566 +/- 83 vs 85 +/- 32 mm/s, p = 0.006) and acceleration (2,600 +/- 760 vs 440 +/- 174 mm/s2, p = 0.050) compared to expert surgeons. Force (16.5 +/- 4.6 vs 18.3 +/- 6.0 N, p = 0.829), position (121 +/- 25 vs 135 +/- 72 mm, p = 0.863), and jerk (19,600 +/- 7,410 vs 2,430 +/- 367 mm/s3, p = 0.138) were similar between groups. A positive correlation was found in novice surgeons between error score and jerk (Pearson correlation, 0.999; p = 0.035). CONCLUSIONS: It is feasible to quantify MMPs in laparoscopic cholecystectomy. Novice and expert surgeons can be differentiated by MMPs; moreover, there may be a positive correlation between jerk and error score in novice surgeons.

Adult↗

Correlation of glomerular permeability, endothelial injury, and postoperative multiple organ dysfunction.

PURPOSE: To determine whether the degree of microalbuminuria correlates with the extent of endothelial cell injury, the severity of illness, and the magnitude of multiple organ dysfunction in patients who undergo emergency surgery. METHODS: We measured the urinary albumin : creatinine ratio (ACR) within 24 h after surgery in 31 patients and examined its relationship with various clinical measurements. RESULTS: The ACR increased during the first 24 h postoperatively. The log ACR correlated with the serum thrombomodulin concentration measured on the same day, but not with the level of plasma von Willebrand factor antigen. The increase in the log ACR correlated with the acute physiology and chronic health evaluation score (APACHE III), the simplified acute physiology score, the multiple organ dysfunction score, and the score of sequential organ failure assessment (SOFA) calculated on the same day, and the blood volume lost during the operation. The log ACR did not correlate with the white blood cell count or the serum C-reactive protein measured at the same time. The log ACR correlated with SOFA on postoperative days 3, 7, and 10, and mortality increased in accordance with the increase in log ACR. CONCLUSIONS: The urinary ACR correlated with the extent of endothelial cell injury, the severity of illness, and the magnitude of multiple organ dysfunction.

APACHE↗

Correlation of continuously monitored regional cerebral blood flow and brain tissue oxygen.

BACKGROUND: The purpose of this study was to investigate the relationship between continuously monitored regional cerebral blood flow (CBF) and brain tissue oxygen (PtiO2). METHODS: Continuous advanced multimodal neuromonitoring including monitoring of PtiO2 (Licox, GMS) and CBF (QFlow, Hemedex) was performed in eight patients after severe subarachnoid haemorrhage (n=5) and traumatic brain injury (n=3) for an average of 9.6 days. Parameters were measured using a flexible polarographic PtiO2-probe and a thermal diffusion CBF-microprobe. FINDINGS: Regarding the whole monitoring period in all patients, the data indicated a significant correlation between CBF and PtiO2 (r=0.36). In 72% of 400 analysed intervals of 30 minutes duration with PtiO2 changes larger than 5 mmHg, a strong correlation between CBF and PtiO2 existed (r>0.6). In 19% of intervals a still statistically significant correlation was observed (0.3<r<0.6). During the remaining 9% no correlation was found (r<0.3). Regarding the clinical stability of the monitoring devices, the CBF monitoring system allowed monitoring of CBF in 64% of the time when PtiO2 monitoring was possible only. Phases of non-monitoring were mostly due to fever of the patient, when the system does not allow monitoring to avoid overheating of the cerebral tissue. CONCLUSIONS: This study suggests a correlation between CBF and PtiO2. The level of PtiO2 seems to be predominately determined by regional CBF, since changes in PtiO2 were correlated in 90% of episodes to simultaneous changes of CBF.

Brain↗

Correlations of calcaneal QUS with pQCT measurements at distal tibia and non-weight-bearing distal radius.

Quantitative ultrasound (QUS) is used for prediction for risks of osteoporotic fractures at various skeletal sites, irrespective of weight-bearing or non-weight-bearing skeletons. In the current study, we investigated the correlation between calcaneal QUS measurements (BUA, VOS, and Soundness) and volumetric trabecular, cortical, and its integral bone mineral density (tBMD, cBMD, and iBMD) using peripheral quantitative computed tomography (pQCT) of the weight-bearing distal tibia and non-weight-bearing distal radius in 198 healthy Chinese women between 40 and 62 years of age. Results showed that BUA, VOS, and Soundness measured by calcaneal QUS were significantly correlated with tBMD, cBMD, and iBMD of both distal tibia and distal radius (r = 0.210-0.447; all P < 0.01). The correlation coefficients of all the individual parameters between calcaneus and distal tibia were correspondingly higher (r = 0.214-0.447; all P < 0.01) than that of distal radius (r = 0.210-0.368; all P < 0.01). QUS Soundness showed the highest correlation (r = 0.447; P < 0.01) with tBMD of distal tibia when comparing with all other parameters between these two measurement devices. Stronger "within-device" correlations (r = 0.640-0.764; all P < 0.01) were found in pQCT measurements between distal tibia and radius. In addition, the largest and significant age-related decline was found in tBMD of the distal radius measured by pQCT and Soundness of the QUS measurement in the postmenopausal group. In conclusion, heel QUS measurement demonstrated slightly better correlation with trabecular bone of the weight-bearing skeleton than that of the non-weight-bearing skeleton measured by pQCT.

Adult↗

Bone mineral density and its correlation with clinical and laboratory factors in chronic peritoneal dialysis patients.

The aim of this study was to assess the clinical and laboratory correlations of bone mineral density (BMD) measurements among a large population of patients on chronic peritoneal dialysis (PD). This cross-sectional, multicenter study was carried out in 292 PD patients with a mean age of 56 +/- 16 years and mean duration of PD 3.1 +/- 2.1 years. Altogether, 129 female and 163 male patients from 24 centers in Canada, Greece, and Turkey were included in the study. BMD findings, obtained by dual-energy X-ray absorptiometry (DEXA) and some other major clinical and laboratory indices of bone mineral deposition as well as uremic osteodystrophy were investigated. In the 292 patients included in the study, the mean lumbar spine T-score was -1.04 +/- 1.68, the lumbar spine Z-score was -0.31 +/- 1.68, the femoral neck T-score was -1.38 +/- 1.39, and the femoral neck Z score was -0.66 +/- 1.23. According to the WHO criteria based on lumbar spine T-scores, 19.2% of 292 patients were osteoporotic, 36.3% had osteopenia, and 44.4% had lumbar spine T-scores within the normal range. In the femoral neck area, the prevalence of osteoporosis was slightly higher (26%). The prevalence of osteoporosis was 23.3% in female patients and 16.6% in male patients with no statistically significant difference between the sexes. Agreements of lumbar spine and femoral neck T-scores for the diagnosis of osteoporosis were 66.7% and 27.3% and 83.3% for osteopenia and normal BMD values, respectively. Among the clinical and laboratory parameters we investigated in this study, the body mass index (BMI) (P < 0.001), daily urine output, and urea clearance time x dialysis time/volume (Kt/V) (P < 0.05) were statistically significantly positive and Ca x PO(4) had a negative correlation (P < 0.05) with the lumbar spine T scores. Femoral neck T scores were also positively correlated with BMI, daily urine output, and KT/V; and they were negatively correlated with age. Intact parathyroid hormone levels did not correlate with any of the BMD parameters. Femoral neck Z scores were correlated with BMI (P < 0.001), and ionized calcium (P < 0.05) positively and negatively with age, total alkaline phosphatase (P < 0.05), and Ca x P (P < 0.01). The overall prevalence of fractures since the initiation of PD was 10%. Our results indicated that, considering their DEXA-based BMD values, 55% of chronic PD patients have subnormal bone mass-19% within the osteoporotic range and 36% within the osteopenic range. Our findings also indicate that low body weight is the most important risk factor for osteoporosis in chronic PD patients. An insufficient dialysis dose (expressed as KT/V) and older age may also be important risk factors for osteoporosis of PD patients.

Absorptiometry, Photon↗

Peripheral blood lymphocyte apoptosis and circulating dendritic cells in patients with systemic lupus erythematosus: correlation with immunological status and disease-related symptoms.

We investigated in vivo the relationship between the degree of peripheral blood lymphocyte apoptosis and circulating dendritic cells (DC) as well as the immunological status in 45 patients with systemic lupus erythematous (SLE). Apoptosis was detected by phosphatidylserine externalization and assays to detect caspase activation. The total DC count (tDC) and their myeloid, mDC1 (BDCA1+) and mDC2 (BDCA3+), and plasmacytoid, pDC (BDCA3+), subtypes were assessed. Moreover, several immunological parameters, such as complement proteins, interferons (IFN), tumor necrosis factor (TNF)-alpha, interleukin (IL)-4, and IL-6 levels were assessed. There were no significant differences in both the intensity of apoptosis and DC counts between active and inactive SLE as well as between untreated patients and those treated with steroids. The incidence of lymphocyte apoptosis correlated positively with T-cell count, both T-helper (p=0.004) and cytotoxic T cells (p=0.001), but not with B or natural killer (NK) cells. The intensity of apoptosis enhanced along with the increase in complement C3 (p=0.016) and decrease in IFN-gamma (p=0.040) levels. The apoptotic cell count correlated with tDC (p=0.031), mDC1 (p=0.007), and pDC (p=0.039) counts. Both tDC and mDC1 counts correlated positively with antinuclear antibody (ANA) titers (p=0.017 and 0.032, respectively). Moreover, tDC correlated with C4 (p=0.039) and pDC with both C3 (p=0.032) and C4 (p=0.007) levels. The DC counts correlated inversely with IFN-gamma (tDC, p=0.038; mDC1, p=0.009), IL-6 (mDC2, p=0.031), or serum IgG levels (tDC, p=0.006; mDC1, p<0.001; mDC2, p=0.001). We found a positive correlation between lymphocyte apoptosis and peripheral blood DC count as well as the level of complement proteins in patients with SLE. The enhanced lymphocyte apoptosis was accompanied by the decrease in concentration of some cytokines, such as IFN-gamma or IL-6, as well as serum IgG level. This finding may reflect pathogenetic events during development of the disease, which include a persistent signal derived from circulating apoptotic lymphocytes, mobilizing the complement system, and attracting peripheral blood DC.

Adult↗

Is there any correlation between objective anal testing, rupture grade, and bowel symptoms after primary repair of obstetric anal sphincter rupture?: an observational cohort study.

PURPOSE: The purpose of this study was to investigate the relationships between the grade of anal sphincter rupture, anal sphincter defect, manometry variables, and anal incontinence. METHODS: A total of 132 females with first-time obstetric sphincter rupture were evaluated by transanal ultrasound, manometry, and scoring of bowel symptoms five months after delivery. RESULTS: Anal sphincter rupture and transanal ultrasound grade correlated with each other ( rs= 0.427, P= 0.001). Both rupture and transanal ultrasound grade correlated with soiling grade ( rs= 0.2, P= 0.03 for both), but in a multiple regression analysis, only transanal ultrasound grade was significant ( P= 0.001) as an independent variable. Anal incontinence score correlated with all the manometry variables, but in a multiple regression analysis, only squeeze pressure was significant ( P= 0.001, beta = -0.4) as an independent variable. Both anal sphincter rupture and transanal ultrasound grade were correlated with manometry variables, but only transanal ultrasound grade was significant as an independent variable after multiple regression analysis. The frequency of transanal ultrasound-verified extensive defect of anal sphincter was higher in rupture Grade 3B (25; 95 percent confidence interval, 12-38 percent) and Grade 4 (45; 95 percent confidence interval, 24-66 percent) than in Grade 3A (2.8; 95 percent confidence interval, -1 to -6.6 percent).(s) (s)CONCLUSION Manometry variables are significantly lower in incontinent females than in continent females, and the Wexner incontinence score was correlated with manometry variables. Both anal sphincter rupture and transanal ultrasound grade correlated with soiling grade and with manometry variables, but in both cases only the transanal ultrasound grade was a significant independent variable.

Adult↗

A genetic analysis of avian personality traits: correlated, response to artificial selection.

Individuals in a range of species consistently differ in their behavior towards mild challenges, over age and time. Differences have been found for several personality traits in a range of species. In great tits these traits have a genetic basis and are phenotypically correlated. Estimates of genetic correlations are, however, fundamental to understanding the evolution of consistent individual differences in behavior. This study analyzed two selection experiments on two avian personality traits, early exploratory behavior and risk-taking behavior. The selection lines used were both started using wild great tits (Parus major) from two natural populations. Genetic correlations were calculated using the response and the correlated response to artificial selection. We found genetic correlations ranging from 0.51 to 0.66, based on individual values, and from 0.84 to 1.00 based on nest means. Genetic correlations can be due to pleiotropic effects or to linkage disequilibrium. The different behavioral traits might therefore have a common genetic basis, possibly constraining independent evolution of personality traits in natural populations. These results are discussed in relation to domain generality and domain specificity of personalities.

Animals↗

Serial correlation and inter-annual variability in relation to the statistical power of monitoring schemes to detect trends in fish populations.

We studied the effects of inter-annual variability and serial correlation on the statistical power of monitoring schemes to detect trends in biomass of bream (Abramis brama) in Lake Veluwemeer (The Netherlands). In order to distinguish between 'true' system variability and sampling variability we simulated the development of the bream population, using estimates for population structure and growth, and compared the resulting inter-annual variabilities and serial correlations with those from field data. In all cases the inter-annual variability in the field data was larger than in simulated data (e.g. for total biomass of all assessed bream sigma = 0.45 in field data, and sigma = 0.03-0.14 in simulated data) indicating that sampling variability decreased statistical power for detecting trends. Moreover, sampling variability obscured the inter-annual dependency (and thus the serial correlation) of biomass, which was expected because in this long-lived population biomass changes are buffered by the many year classes present. We did find the expected serial correlation in our simulation results and concluded that good survey data of long-lived fish populations should show low sampling variability and considerable inter-annual serial correlation. Since serial correlation decreases the power for detecting trends, this means that even when sampling variability would be greatly reduced, the number of sampling years to detect a change of 15%.year(-1) in bream populations (corresponding to a halving or doubling in a six-year period) would in most cases be more than six. This would imply that the six-year reporting periods that are required by the Water Framework Directive of the European Union are too short for the existing fish monitoring schemes.

Animals↗

Correlation of abnormal Q waves, coronary pathology, and ventricular contractility.

Four hundred and ninety-two patients with coronary artery disease underwent analysis of their electrocardiograms, coronary arteriograms, and ventriculograms. Significant Q-waves were correlated with critical coronary occlusions (greater than or equal 75 per cent obstruction) and ventricular contractility. It was found that Q-waves correlate equally well with ventriculographic abnormalities and critical coronary occlusions. The Q-wave correlation varied from 77 to 87 per cent, depending on the area of myocardium under consideration, except for true posterior myocardial infarction, which correlated 55 per cent with ventriculographic abnormalities and 55 per cent with critical coronary occlusions. Significant Q-waves in Leads II, III, and aVF are better indicators of ventriculographic abnormality than in Leads III and aVF alone, whereas Q-waves in the latter two leads are more definitive than in Lead III alone. Patients who have critical coronary occlusions and normal electrocardiograms have normal ventriculograms in 71 to 78 per cent of the cases, again depending on the area of the myocardium under consideration. Thus, the normal electrocardiogram correlates better with the ventriculogram than with coronary pathology. The abnormal electrocardiogram correlates equally well with both.

Coronary Angiography↗

Analysis of phase-angle histograms from equilibrium radionuclide studies: correlation with semiquantitative grading of wall motion.

Quantitative wall motion assessment from gated radionuclide left ventriculograms using phase analysis was studied in 14 subjects (6 normal volunteers and 8 patients with previous acute myocardial infarction). The standard deviation and skewness of the phase-angle histograms were determined from both global and segmental left ventricular (LV) regions of interest (septal, apical and posterolateral). Studies were performed at rest, after administration of atropine and after combined administration of phenylephrine and atropine. Both the standard deviation and skewness showed significant correlations with semiquantitative wall motion scoring. From the global analyses, the highest correlations were found after atropine administration (r = 0.86, p less than 0.001 for standard deviation and r = 0.72, p less than 0.001 for skewness). Nevertheless, deterioration in global wall motion scores correlated poorly with directional changes in standard deviation (r = 0.06, difference not significant) or skewness (r = 0.33, p less than 0.05). No significant correlation between skewness or change in skewness and wall motion scores were found with the segmental analyses. The maximal correlation between segmental standard deviation and segmental wall motion grading was again noted after atropine administration (r = 0.68, p less than 0.001), but deterioration in grading did not correlate with similar deterioration of the standard deviation (r = -0.05, difference not significant). Based on 90% confidence limits for normal standard deviation and skewness, an abnormal standard deviation (greater than 14.5) identified 13 of 28 wall motion disorders (sensitivity 46%), whereas an abnormal skewness (greater than 1.4) identified 1 of 28 wall motion disorders (sensitivity 4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Correlations between human salivary levels of lysozyme, lactoferrin, salivary peroxidase and secretory immunoglobulin A with different stimulatory states and over time.

Within-subject correlations for the levels of these salivary proteins were determined in unstimulated and stimulated parotid saliva collected from 8 subjects and for stimulated parotid saliva collected from the same subjects once a week for a 4-week period. Initial correlations between unstimulated and stimulated samples were high and statistically significant (p less than 0.05) for all four proteins. When data were adjusted for variation attributable to flow rate and total protein, some correlations remained the same and those for lysozyme, lactoferrin and salivary peroxidase increased. However, the correlation for secretory immunoglobulin A decreased to a point where it was no longer statistically significant. In the weekly comparison, within-subject correlations across weeks were significant (p less than or equal to 0.05) for lysozyme, lactoferrin and salivary peroxidase, but not for immunoglobulin A. After adjustment for flow rate and total protein, the pattern of correlation was unchanged. Thus the relative rankings of subjects for levels of lysozyme, lactoferrin or salivary peroxidase may be consistent across stimulatory states, even though absolute concentrations may change; levels of these proteins in stimulated parotid saliva may be maintained over time. Secretory immunoglobulin A appears to be more subject to short-term variation.

Adult↗

Naloxone affects both pharmacokinetics and pharmacodynamics of morphine. Application of direct correlation analysis.

Direct correlation analyses between the distribution of morphine (pharmacokinetics) and the biochemical effects of the drug on monoamine metabolism (pharmacodynamics) are reported for dissected regions of the brain. Determinations of morphine and monoamine-related substances were carried out in the same sample by high performance liquid chromatography with electrochemical detection. Naloxone, an antagonist of morphine, significantly shortened the biological half lives of morphine in both the blood and brain tissue. Such pharmacokinetic behavior appeared to be related to the contractive effect of morphine on the bile duct, and naloxone facilitated the excretion of morphine via this route. In the striatum, significant correlations were observed between the concentrations of the metabolites of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), and morphine with a shift to the right in the concentration-response curve on naloxone treatment indicating competitive antagonism. While significant correlations were also observed in this brain region for the metabolites of noradrenaline, 3-methoxy-4-hydroxyphenylethylene glycol (MOPEG), and 5-hydroxytryptamine, 5-hydroxyindoleacetic acid (5-HIAA), a shift to the right did not occur. Significant correlations and shifts were noted for DOPAC, HVA and MOPEG in the hypothalamus. However, no correlation was found between the concentrations of 5-HIAA and morphine in this region. In other regions such as the hippocampus and medulla oblongata, similar correlations and shifts were not observed for MOPEG and 5-HIAA or for DOPAC and HVA.(ABSTRACT TRUNCATED AT 250 WORDS)

3,4-Dihydroxyphenylacetic Acid↗

Structure of intestinal-mucus glycoprotein from human post-mortem or surgical tissue: inferences from correlation analyses of sugar and sulfate composition of individual mucins.

The carbohydrate composition of 14 human, small-intestine mucins, obtained at surgery or post-mortem, varied greatly from specimen to specimen with respect to individual sugars and average chain-length (ratio of total carbohydrate to N-acetylgalactosamine). Three monosaccharides, galactose, N-acetylglucosamine, and fucose gave good correlations with each other, and to total carbohydrate content, when expressed as a ratio to the chain-terminal N-acetylgalactosamine residue. In contrast, sialic acid gave a good correlation only with N-acetylgalactosamine. In eight specimens the molar sulfate to N-acetylgalactosamine ratios gave good correlation with the ratios of galactose to N-acetylgalactosamine, N-acetylglucosamine to N-acetylgalactosamine, and total carbohydrate to N-acetylgalactosamine. These results indicate that the intraspecies variability of intestinal-mucin carbohydrates arises from the interdependent addition of galactose, N-acetylglucosamine, fucose, and sulfate residues. Partial correlation-analysis indicated that proportions of N-acetylglucosamine and fucose were correlated only through a mutual dependence on galactose, suggesting that the key elongating-factors involve the addition of galactose residues. The number of sialic acid residues per oligosaccharide chain remained relatively unchanged from mucin to mucin, and this, coupled with the close correlation between the proportions of sialic acid and N-acetylgalactosamine, suggests that almost all sialic acid residues are bound to the core N-acetylgalactosamine residues in intestinal mucin. High fucose-to-sialic acid and high sulfate-to-sialic acid ratios reported in some disease states are explained as the consequence of chain elongation.

Amino Acids↗

Cardiac and respiratory correlations with unit discharge in human amygdala and hippocampus.

Animal studies have shown that epileptiform seizures can cause cardiac arrhythmias and death. The amygdala and hippocampus are implicated in epileptogenesis and autonomic and respiratory control. We examined cardiac and respiratory correlations with single cell discharge in hippocampus and amygdala of patients with epilepsy. We recorded respiration, ECG, and neuronal discharge of amygdala and hippocampus from patients undergoing chronic depth electrode monitoring. Cross-correlation histograms were used to test for neuronal discharge timing relationships with inspiration or the ECG. Inspiratory time, respiratory period and heart rate were calculated for each breath, and linear regression was used to test for correlations with tonic unit rate. Of 183 cells from 24 patients, 20% had cardiac timing relationships and 23% showed tonic correlations with changes in heart rate. Only 2% had timing relationships with the respiratory cycle, while 15% showed tonic rate relationships with respiratory period. Recording sites did not differ in mean discharge rate or proportion of cells showing these correlations. These results indicate that a significant number of human forebrain cells show discharge modulation by the cardiac cycle and discharge rate correlation with changes in respiration and heart rate. This is supportive of animal models designed to explore the role of mesial temporal lobe structures in regulation of cardiovascular and respiratory systems, although a lower proportion of cells in human temporal lobe showed timing relationships with respiration and there was no clear evidence of anatomic specificity between amygdala and hippocampus.

Amygdala↗