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PubMed1991

Iris vasculopathy in exfoliation syndrome. An immunocytochemical study.

Samples of control iris tissue obtained from seven enucleated eyes and nine exfoliative iridectomy specimens were prepared for an immunocytochemical study of the matrix in the walls of iris vessels. The distribution of collagen types I, IV and laminin was studied in normal and exfoliative vessels. Laminin was an integral component of exfoliation material and was present mainly in the matrix of the outer surface of normal vascular cohort cells. The laminin content in the latter location was reduced in vessels in which exfoliation aggregates were not visible. Collagen type IV was absent from exfoliation material. While type I was present in the deposits, it was considered to represent a residue of native normal tissue. Exfoliation deposits appeared to stimulate the synthesis of collagen types I and IV at an early stage of the disease.

Aged↗

PubMed1979

Implications of alternative sampling strategies for emergency medical service evaluation.

Evaluations of emergency medical service (EMS) programs have been ambiguous, due in part, to problems of sample definition. Four different sampling strategies were studied: 1) all patients in cardiac arrest; 2) patients with a final diagnosis of myocardial infarction (MI); 3) patients with an emergency room diagnosis of "rule out MI"; and 4) patients identified by the ambulance team as a possible MI. Using a regional data base of all ambulance runs, we created study samples based on each of these strategies and measured the error that may be introduced as a result of sample selection. Bias was measured along three parameters of EMS system performance: 1) observed incidence of MI in the ambulance system; 2) condition recognition--the ability of the ambulance team to correctly identify acute cardiac patients; and 3) emergency room and hospital mortality rates. The emergency room diagnosis strategy systematically excludes all false-positives, while samples based on the ambulance team's assessment omit all false-negatives. The final diagnosis strategy yields significant underestimates of cardiac mortality. Samples restricted to cardiac arrests result in biased estimates of both the incidence of MI and the number of deaths.

Ambulances↗

PubMed1991

Fasting serum insulin in relation to fat distribution, serum lipid profile, and blood pressure in European women: the European Fat Distribution Study.

Samples of 38-year-old women were randomly selected from five European centers: Ede (The Netherlands), Warsaw (Poland), Gothenburg (Sweden), Verona (northern Italy), and Afragola (Naples-southern Italy). In total, 452 healthy women were studied. Anthropometric measurements were taken by one operator in each country after common training of all operators and blood parameters of all women were determined in one laboratory. Body mass index (BMI) was different among centers, mainly due to the higher values in southern Italy. Women from southern Europe had more central fat distribution than women from north European centers. Fasting serum insulin was higher in women from Poland and The Netherlands than in the other three centers. After adjustment for BMI, fasting insulin was significantly related to subscapular skinfold, subscapular to triceps skinfold ratio, waist circumference, and waist to thigh circumference ratio, although the partial correlations varied somewhat between the centers. In the pooled data, waist circumference showed the highest correlations with fasting serum insulin when adjusted for BMI. Fasting serum insulin showed significant partial correlations, adjusted for BMI, with lipid profile and blood pressure only in women from the two Italian centers. In the pooled data, fasting serum insulin was significantly positively correlated with serum triglycerides and total cholesterol and negatively to high-density lipoprotein (HDL) cholesterol and HDL/total cholesterol, independently of BMI and waist circumference. While blood pressure was not related to insulin in the pooled women, when adjusted for BMI and waist circumference; here as well, there were some differences in relationships between the centers.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗

PubMed1991

The relationship between stressful life situations and changes in alcohol consumption in a general population sample.

Studies on the relationship between stressful life situations and alcohol consumption have almost exclusively been based on retrospective information from clinical populations. We conducted multiple regression analyses of the relationship between presumed stressful life conditions in 1965, life events during 1966-73 and psychosocial factors and amount of increase or decrease in alcohol consumption from 1965 to 1974 adjusting for age, alcohol consumption, education and health status in 1965. Data from surveys in 1965 and in 1974 in a general population sample of 4,864 subjects from Alameda County, California were used. The magnitude of the associations between the presumed stressful life situations and amount of change was generally low, although a few were statistically significant. However, among those aged 65 years and above, and especially among men, some of the associations were strong, but imprecise due to the low number of subjects in those ages. While a number of variables were associated with increase or decrease in alcohol consumption, the R2-values indicated that these variables explained little of the variation over time in alcohol consumption. Thus, people in general seem to cope with stressful life situations by means, other than a longstanding increase in alcohol consumption.

Adaptation, Psychological↗

PubMed1991

Expression of fragile-X in a female fetus diagnosed after chorionic villus sampling.

Study of different tissues of an aborted female fetus showed similar levels of fragile-X expression (6.3-9.2 per cent) and of early replication of the FRAXA-positive cells (50-66 per cent) in fetal tissues. Different culture media did not significantly affect either investigation. It is suggested that the distribution of X-inactivation in FRAXA-positive chorionic villus cells of a female fetus might indicate her future phenotype.

Cells, Cultured↗

PubMed1989

Human-parathormone assay for use in dogs: validation, sample handling studies, and parathyroid function testing.

Ten commercially available parathormone (PTH) assays were competitively validated, using dilutional parallelism, intra-assay and interassay coefficients of variation, and sensitivity and measured responses of 2 dogs to calcium and EDTA infusions. A 2-site immunoradiometric assay for intact human-PTH was superior to the others for estimating canine-PTH, met the criteria for validity, and was further investigated. A series of sample-handling studies was performed. Serum and plasma samples stored at 24 C lost 15% (n = 5; P less than 0.05) of PTH between 2 and 24 hours. This did not occur at 6 C. The mean PTH concentration of sera from blood samples clotted at 24 C was 6% (P less than 0.05) higher than equivalent EDTA samples. Serum samples stored at 6 and 37 C deteriorated 35% and 100% (n = 5; P less than 0.05), respectively, after 1 week, whereas samples stored at -20 and -70 C for 4 weeks did not deteriorate. There was no significant deterioration of PTH in samples frozen (-40 C) and thawed up to 7 times (n = 5). Parathyroid function testing was investigated by use of 2-hour infusions of disodium EDTA (25 mg/kg/h), 10-minute infusions of calcium gluconate (3 mg of elemental calcium/kg/10 min), and physiologic saline controls (n = 8). Renal function was monitored before and after EDTA infusion by exogenous creatinine clearance. Infusion of disodium EDTA increased mean PTH concentration from 67 (time 0) to 317 and 235 pg/ml at 90 and 180 minutes, respectively (P less than 0.001). Infusion of calcium gluconate decreased mean PTH concentration from 84 (time 0) to 14 and 12 pg/ml at 15 and 60 minutes, respectively (P less than 0.005). There were no observable side effects of the infusions in normal conscious dogs and no differences in exogenous creatinine clearance after EDTA infusion.

Animals↗

PubMed1978

Assessment of expectorated sputum for bacteriological analysis based on polymorphs and squamous epithelial cells: six-month study.

Samples of sputum were examined microscopically to determine their suitability for routine culture. When the number of squamous epithelial cells per field was less than 10, the number of bacterial species generally fell within the range of one to four. Squamous epithelial cells were not always a true indication because some unmarked transtracheal specimens showing more than 10 squamous epithelial cells also gave a range of isolation falling between one and four. When the presence of 25 or more polymorphs was used as the parameter, the number of bacterial isolates generally fell within the range of one to three, but this resulted in positive overbiasing with consequent rejection of valid specimens. Later it was found that when a differential system using both polymorphonuclear cells and squamous epithelial cells was applied, a significant number of specimens could be salvaged which would otherwise have been discarded.

Epithelial Cells↗

PubMed1988

Quantitative microanalysis of bile acids in biological samples. Collaborative study.

The analysis of bile acids in biological samples has always presented a problem because of their complex nature and low concentration. Recently, newer analytical procedures for bile acids have become available, including enzymatic analysis, radioimmunoassay, thin-layer chromatography (TLC), gas chromatography, high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring (SIM). However, they differ greatly with respect to specificity, sensitivity, accuracy and simplicity. On the other hand, the choice of analytical procedure differs according to the specific aims and the nature of biological samples to be analysed. These newer procedures have been compared in a double-blind fashion by distributing bile, plasma and urine samples to seven participating laboratories. GC-MS-SIM was found to be the most sensitive and reliable, but it requires other procedures for preliminary clean-up and fractionation steps. Enzymatic analysis is simple and gives small analytical errors but tends to over-estimate plasma bile acids. Radioimmunoassay gives variable results but is useful as a screening procedure for large numbers of plasma samples. TLC gives reliable results for biliary bile acids in experienced hands, except for differentiation between conjugated dihydroxycholanoic acids. HPLC, whether using derivatization or with fixed 3 alpha-hydroxy steroid dehydrogenase detection, is suitable for the analysis of major bile acids in normal human serum but not for the identification of unknown minor peaks.

3-Hydroxysteroid Dehydrogenases↗

PubMed1979

Contaminant levels in animal feeds used for toxicity studies.

Samples of commercial feeds for laboratory rats, guinea pigs, cats, monkeys, rabbits, and hamsters were collected and analyzed qualitatively and quantitatively for selected antibiotics, trace metals, pesticides (organophosphates and chlorinated hydrocarbons), natural agents, and polychlorinated biphenyls (PCBs). The results indicated that antibiotics, parathion, diazinon, aldrin, and the aflatoxins were not detected, whereas, metals, chlorinated hydrocarbon pesticides (except aldrin), and PCBs were continually present. Malathion and estrogen were found occasionally.

Animal Feed↗

PubMed1979

Quantitation of hemoglobin F. An interlaboratory study.

Samples of whole blood from four hematologically normal adults and from two individuals with increased fetal hemoglobin levels were shipped to laboratories participating in the 1976 and 1977 Center for Disease Control (CDC) hemoglobinopathy proficiency testing surveys. The data from these surveys were used to evaluate the interlaboratory variability of current methods used to quantitate hemoglobin F (Hb F). Results of Hb F quantitation obtained from more than 100 laboratories than voluntarily participated in the survey were compared with those obtained from 21 reference laboratories. Individual values for all samples varied greatly among laboratories and among methods. Results returned by most of the laboratories were outside two standard deviations of the reference laboratory mean and were not accurate enough to differentiate between a normal level and an increased, abnormal level.

Fetal Hemoglobin↗

PubMed1975

Unilateral brain lesions and MMPI performance: a preliminary study.

Samples of 15 Ss with right- and 20 Ss with left-hemisphere brain lesions secondary to war-related penetrating missile wounds were matched for age, education, and recency of injury and evaluated with the MMPI. Right-hemisphere lesioned Ss produced a composite profile with all scales within normal limits. In contrast, the composite profile of left-hemisphere lesioned Ss showed significant elevations on the Sc, D, and Hs clinical scales, suggesting increased psychopathological responses in such Ss. Although the general configurations of the composite MMPI profiles in the two samples were similar, significant differences in the elevation of both validity and clinical scales were obtained. The results tend to support previous findings of a depressive-catastrophic reaction in patients with lesions in the dominant hemisphere, while not supporting the euphoric-indifference response in nondominant-hemisphere lesioned Ss.

Adult↗

PubMed1990

Degree of correspondence between contractile and oxidative capacities in horse muscle fibres: a histochemical study.

Samples taken from the middle gluteal muscle of 95 untrained adult horses of different ages and sex were subjected to histochemical analysis using the myosin adenosine triphosphatase (m-ATPase) and nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR) staining techniques. Fibres were classified into types I, IIA and IIB according to m-ATPase activity after preincubation at pH 4.4. The percentage of FT (Fast-Twitch Glycolytic) fibres and the proportion of IIB fibres with "high" and "low" oxidative capacity were determined in serial sections stained for NADH-TR. Statistical analysis revealed a significantly higher proportion of IIB fibres than FT fibres (P less than 0.001), though both percentages were correlated. Thus, 72.2 +/- 17.6% of type IIB fibres showed low oxidative capacity, but the remaining 27.8 +/- 17.6% showed high aerobic potential, and thus did not correspond to FT fibres. These results confirm that the contractile capacity of a muscle fibre does not determine its oxidative profile. The different types of muscle fibre should thus be classified solely according to m-ATPase activity, since this characteristic is related to the molecular structure of contractile proteins. Oxidative capacity should be assessed separately, and not be used as a criterion for fibre classification in horses.

Animals↗

PubMedDate not supplied

Determination of sulfur amino acids and tryptophan in foods and food and feed ingredients: collaborative study.

Samples of 4 foods, 1 animal feed, isolated soy protein, and beta-lactoglobulin were analyzed by 9 laboratories to determine concentrations of cysteine as cysteic acid, methionine as methionine sulfone, and tryptophan. Sulfur amino acids were determined by AOAC method 43.A08-43.A13 for food and feed ingredients, in which samples are oxidized with performic acid before protein hydrolysis with 6N HCl. Tryptophan was determined after protein hydrolysis with 4.2N NaOH. In both methods, free amino acids were separated by ion-exchange or reverse-phase chromatography. Each laboratory was provided with detailed methods and with sealed vials containing solutions of standards. Samples were analyzed in duplicate, and variation between laboratories was determined. Coefficients of variation between laboratories for the 6 samples ranged from 5.50 to 11.8% for methionine as methionine sulfoxide, 8.59 to 17.3% for cysteine as cysteic acid, and 3.87 to 16.1% for tryptophan. Amino acid recoveries were determined by analysis of beta-lactoglobulin and were based on expected levels of each amino acid obtained from amino acid sequence data. The mean recovery of cysteine was 97% with a range of 88-119%. For methionine, mean recovery was 98% (range 89-115%) and for tryptophan, 85% (range 59-102%). Method 43.A08-43.A13 for food and feed ingredients has been adopted official first action for determination of cysteine and methionine in processed foods. The alkaline hydrolysis method has been adopted official first action for determination of tryptophan in foods and food and feed ingredients.

Amino Acids, Sulfur↗

PubMed1979

Atomic absorption determination of tin in foods: collaborative study.

Samples of green beans, applesauce, and a fruit juice were fortified with tin at 3 levels. Collaborators were asked to digest the samples, using HNO3-H2SO4, add methanol to enhance the absorption signal, and aspirate directly, using a nitrous oxide-acetylene flame. Results were received from 8 laboratories including 4 from Europe. However, only 6 laboratories used the prescribed methodology. All results were considered acceptable. The method has been adopted as interim official first action.

Beverages↗

PubMed1991

Multidimensional work sampling to study the activities of decentralized clinical pharmacists.

Self-reported multidimensional work sampling (MDWS) was used to study the activities of decentralized clinical pharmacists at six hospitals in Portland, Oregon, and Seattle-Tacoma, Washington, in March through June 1989. A community hospital, a university hospital, and a hospital associated with a health maintenance association were selected in each city, and pharmacists at each site who provided clinical services were recruited. Each pharmacist wore a random reminder device and recorded the activity during which the device sounded by writing on a card numbers assigned to describe work activity, contact, location, and function. Of 6609 classifiable observations, 34.5% (2280) were of clinical activities and 35.8% distributive activities. Pharmacists spent 28.6% of their clinical time reviewing and assessing patients' charts, 17.1% on clinical rounds, 15.9% on activities related to therapeutic drug monitoring, 10.2% providing drug information, 11.6% attending or giving formal education, 6.1% doing research, and 2.6% attending meetings. The average pharmacist spent less than 10 minutes each day with patients but spent a substantial portion of time providing clinical services to other health professionals. Self-reported, multidimensional work sampling appears to be a valuable method for describing and monitoring decentralized pharmacists' work activities at multiple sites and work settings.

Hospitals, Community↗

PubMed1990

[Pneumocystis carinii: an optic and electron microscopy study in samplings of 16 cases].

Sixteen patients with P. carinii infection were studied between 1977 and 1989; 12 were male and the age ranged from 4 months to 53 years old. 19 samples, 5 from autopsy, 7 from biopsy and 7 cytological aspirates were stained with hematoxylin-eosin, Gomori-Grocott, Giemsa and 0 toluidine. Autopsy material was studied by transmission electron microscopy. The diagnosis was made premortem in 11 patients. AIDS was the underlying disease in 6 patients, the rest having other immunodepressant conditions. P. carinii infection was limited to the lung in all patients. The Gomori Grocott stain gave positive results in all cases; cytological studies were generally noncontributory. Opportunistic agents were found in 4 patients (aspergillus, cytomegalovirus and C. neoformans).

Adolescent↗

PubMed1977

Renal vein renin activity: a prospective study of sampling techniques and methods of interpretation.

Seventy patients undergoing renal arteriography were studied prospectively to define optimal techniques of renal venous sampling and to establish the most appropriate methods for interpretation of renal vein renin and activity (RVRA). Plasma renin activity values from the aorta, the antecubital vein and the lower inferior vena cava were nearly identical. The relationship between renal vein renin activity in the two renal veins was not influenced by lack of simultaneous sampling or by contrast administration. Thirty-one patients with normal arteriograms had a mean RVRA ratio (right over left) of 1.12 +/- .11 (mean +/- SEM) but RVRA difference (right minus left) of only 0.02 +/- .11 ng/ml/hr. In contrast 16 patients with "significant" (greater than 70%) narrowing of the main renal artery had a mean RVRA ratio (involved over uninvolved) of 4.3 +/- 1.2 and a mean RVRA difference (involved minus uninvolved) of 3.9 +/- 1.4 ng/ml/hr. Seven patients (22%) with normal arteriograms had "abnormal" RVRA ratios (greater than or equal 1.5) but corresponding RVRA differences within one standard deviation of the group mean. Thus the difference inRVRA between both renal veins may more accurately reflect a patient's renovascular status than does the corresponding RVRA ratio. An "abnormal" RVRA ratio alone inadequately indicates the presence of renal ischemia.

Humans↗

PubMed1991

An international study of the relationship between alcohol consumption and postmenopausal estradiol levels.

Because of the beneficial effect of estrogens on the risk of cardiovascular disease and osteoporosis in postmenopausal women, the factors which influence endogenous postmenopausal estrogen levels are of substantial importance. The major source of postmenopausal estrogen is the aromatization of androgens to estrogens. Because alcohol is reported to increase aromatization rates, the relationship between serum estradiol and moderate alcohol consumption was examined in a group of 128 healthy Pittsburgh postmenopausal women, and a significant direct association was found. In order to address the generalizability of this finding, 3 comparable study populations of healthy postmenopausal women were recruited: 62 in Copenhagen, 34 in Lisbon and 20 in Madrid. Although no association was detected in the Madrid study sample, in both the Copenhagen and Lisbon study populations, not only were estradiol levels significantly increased in alcohol users as compared to abstainers, but also estradiol levels were significantly correlated with total weekly drinks consumed. Based on these findings in study samples of healthy postmenopausal women from Pittsburgh, Copenhagen and Lisbon, we conclude that the increase in estradiol levels seen with moderate alcoholic beverage consumption is not an isolated finding and speculate that moderate alcohol consumption by healthy postmenopausal women may have beneficial effects.

Alcohol Drinking↗