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PubMed1985

Determination of vitamin E in microsamples of serum by liquid chromatography with electrochemical detection.

In this procedure for determination of vitamin E by "high-performance" liquid chromatography with electrochemical detection, 25-microL serum specimens are deproteinized with ethanol. Vitamin E (alpha-tocopherol), its derivatives (beta- and gamma-tocopherols), and the internal standard (delta-tocopherol) are extracted into heptane and the extract is evaporated and the residue reconstituted with methanol before injection into the chromatograph. Within- and between-run CVs for an alpha-tocopherol concentration of 13.6 mg/L were 5.1% (n = 28) and 6.0% (n = 5), respectively. The standard curve is linear to 100 mg/L; the minimum concentration detectable is 0.1 mg/L. Analytical recovery ranged from 99.8% to 104.8%. In 36 specimens collected from apparently healthy subjects who were not taking vitamin supplements, alpha-tocopherol as determined by this method ranged from 4.3 to 9.7 mg/L, from 1.8 to 3.9 mg/L for beta- and gamma-tocopherols. Results by this method (y) and an HPLC-ultraviolet method (x) correlate reasonably (r = 0.81): y = 0.88x - 0.55 mg/L (n = 45). This procedure is adaptable to automated analysis, and the small sample requirement facilitates its applicability to neonates.

Adult↗
PubMed1985

[Microanalysis on dry reactive supports].

Among actual technological developments in clinical chemistry, the use of dry reagents fixed on a solid support is particularly advantageous for assays in emergency. Reflectometry is used for the measurement and was analysed in terms of principles and measurement devices. To day, only one apparatus Seralyser is furnished by Ames and we have evaluated its performances. However, other apparatus are in evaluating. Thus, Ektachem Kodak 400, 700 or DT 60 employs multilayer slides. Reflotron from Boehringer allows the direct use of blood samples. Stratus with a fluorimetrie measurement is adapted to drug assays. This new technology some permits interesting applications derived from basic research but arises some problems for the realisation of the as well as the role of the clinical chemist.

Blood Chemical Analysis↗
PubMed1984

A kit for citrate in foodstuffs adapted for assay of serum and urine.

A kit method for rapid analysis of citrate in foodstuffs, based on use of citrate lyase (EC 4.1.3.6), has been adapted and evaluated for use with clinical samples. Membrane filters removed serum proteins, which interfere with the analysis, and reagent and sample volumes were decreased from those in the manufacturer's protocol, thereby decreasing the cost of the assay. Using gravimetrically prepared citrate standards, we determined that assay results varied linearly with concentration up to sixfold the upper reference limit for serum citrate. Intra- and interassay variation were within acceptable limits (CVs less than 3% and less than 8.5%, respectively). Kit reagents were stable for four weeks at -20 degrees C. Assay results were unaffected by hemolysis or other biochemical interferences. The method evidently provides a rapid, convenient microassay for citrate in clinical samples.

Bilirubin↗
PubMed1981

[Collagenolytic activity of human cervical tissue, following local application of prostaglandin E2 (PG E2), using a portio adapter (author's transl)].

A biological assay was used to determine collagenolytic activities in cervical tissue of 16 patients, who had received PG E2 treatment for cervical ripening, and of another 16 patients in whom cervical ripening had occurred spontaneously. The cervical tissue required for the assay was obtained by small biopsy after delivery. The first group of probands received 1.25 mg PG E2 in aqueous solution which was locally applied to the cervix through a portio adapter. Mean lysis, related to a tissue sample of 2 mm in diameter and following twelve hours of incubation, amounted to 7.82 +/- 2.58 mm2 in the treated group and to 5.39 +/- 1.06 mm2 in the untreated group. A statistically significant difference of p less than 0.005 was, accordingly, obtained by a Student-t test of unpaired observation. The results of the author's tests have shown that rise in collagenolytic activity was one of the major effects when prostaglandin was locally applied for cervical ripening.

Administration, Topical↗
PubMed1994

[Visceral form of human anthrax imported from Africa].

Widespread vaccination has largely eliminated anthrax in Europe (the last case was reported in France in 1972) but the disease remains endemic in many developing countries. The usual cutaneous presentation (malignant pustules) is much more familiar than the various visceral manifestations including digestive tract, pulmonary or meningeal signs. We report a case of a 33-year-old immigrant living in France who was hospitalized for asthenia, dyspnoea, mucopurulant expectoration and moderate diarrhoea 3 days after a 3-month stay in Senegal and Gambia. The temperature was 39 degrees C at admission and blood pressure 110/70 mmHg. Crepitants were heard at the base of the right lung and the rest of the physical examination was normal. Blood was drawn for culture. Laboratory tests and the chest X-ray led to the diagnosis of pneumopathy and a treatment of amoxicillin and clavulanic acid was given with oxygenotherapy. The patient's temperature returned to normal but over the next 48 hours the dyspnoea worsened together with the black diarrhoea. The abdomen was painful. There were no skin lesions. The chest X-ray revealed an extension of the bilateral pulmonary images and bilateral pleural effusion. Laboratory tests revealed thrombopenia (platelet count 38,000/mm3) hyperleukocytosis (WBC 48,000/mm3) and haemolysis (Hb 4 milligrams). The diagnosis was made on the basis of the initial blood cultures which were positive for Bacillus anthracis. All other samples were negative, including HIV serology. Despite adapted antibiotic therapy (penicillin G, 8MU/day, was initiated on day 2), multiple organ failure occurred with septic shock and pulmonary oedema. The patient died in the intensive care unit on day 7. Fatal outcome due to anthrax is described in 25% of the visceral forms but reaches 100% in cases of septicaemia. The haemolysis observed in this case is not mentioned in the classical descriptions of anthrax. When treating septic syndromes in patients who have returned from endemic zones, clinicians should entertain the diagnosis of anthrax since the risk of fatal outcome is increased greatly in case of delayed diagnosis.

Adult↗
PubMed1993

The morphotype in a group of peri-pubertal soccer players.

Few morphological data are available for adolescent soccer players (SP), a lack that could affect young-age talent selection. In order to collect lacking data for SP, 50 performers aged 13.1 +/- 0.5 years old were checked in one of the main "vivariums" of talented "A League" SP. All subjects were measured according to the Heath/Carter anthropometric somatotype method and subsequently, the results were compared with those found in relevant literature for adolescents. To gain further insight, the sample was subdivided into two classes, according to their performance level: beginners (B, n = 26) and those experienced (E, n = 24). Between B and E subjects significant differences were found for: weight, abdominal skinfold, calf circumference, body density (0.05 < p < 0.01); height, tricipital skinfold, humerus biepicondylar width, ponderal index, LBW, endo and ectomorph components (p < 0.01). B somatotype resulted to be: 1.6-4.3-3.5; while E: 2.2-4.5-2.9. Both in E and B sub-groups the distribution of somatotypes according to their component dominance revealed to be rather similar, indicating a substantial homogeneity inside the subgroups. When compared with adult SP, the whole sample shows a morphotype that is already adapted for soccer. Observing this, it is possible to infer that our adolescent group contains the morphotype needed to perform well (and probably to excel), in the considered sporting activity.

Adolescent↗
PubMed1996

[The most common vital events in women 45-64 years of age. Repercussions as psychophysical stressors].

OBJECTIVE: To find what vital events middle-aged women in our society most often experience and their influence as stress factors on physical health and subjective psychological well-being. DESIGN: A multivariant transversal study. SETTING: 5 primary care centres in Valencia and Alicante. PARTICIPANTS: 306 women chosen at random among those seen at these health centres. MEASUREMENTS AND MAIN RESULTS: Frequency analysis of vital events. Correlation analysis with questionnaires on physical symptoms and diseases, psychological well-being, work situation, emotional behaviour, sexuality and relationships with their partner. ANOVA: dividing the sample into 2 groups based on mean adaptive effort. The most common events numbered 23. The ANOVA showed a significant association between greater adaptive effort and negative emotional behaviour, personal control, material well-being, relationship with the partner, and physical and psychological symptoms. CONCLUSIONS: The relevance of daily events as generators of stress was confirmed, as was the impact of these and major events on these women's physical and psychological health. The importance of attending women at this stage of their lives from an integrated and interdisciplinary perspective, which tackles the physiological, psychological and cultural features together, was shown.

Analysis of Variance↗
PubMed1997

Factor analysis of the Mayo-Portland Adaptability Inventory: structure and validity.

Principal-components (PC) factor analysis of the Mayo-Portland Adaptability Inventory (MPAI) was conducted using a sample of outpatients (n = 189) with acquired brain injury (ABI) to evaluate whether outcome after ABI is multifactorial or unifactorial in nature. An eight-factor model was derived which explained 64-4% of the total variance. The eight factors were interpreted as representing Activities of Daily Living, Social Initiation, Cognition, Impaired-Self-awareness/Distress, Social Skills/ Support, Independence, Visuoperceptual, and Psychiatric, respectively. Validation of the Cognition factor was supported when factor scores were correlated with various neuropsychological measures. In addition, 117 patient self-rating total scores were used to evaluate the Impaired Self-awareness/Distress factor. An inverse relationship was observed, supporting this factor's ability to capture the two-dimensional phenomena of diminished self-awareness or enhanced emotional distress. A new subscale structure is suggested, that may allow greater clinical utility in understanding how ABI manifests in patients, and may provide clinicians with a better structure for implementing treatment strategies to address specific areas of impairment and disability for specific patients. Additionally, more precise measurement of treatment outcomes may be afforded by this reorganization.

Adolescent↗
PubMed1997

[Morphological studies of hydroxyapatite crystals exposed to disodium pamidronate].

"In vitro" effects of disodium pamidronate on hydroxyapatite crystals morphology, and some "in vivo" data from bone powder of tibia and vertebrae from treated young and mature rabbits are here reported. Hydroxyapatite, synthesized following Rigoli et al method, and bone powder from rabbits were studied with X-ray, infrared and raman emission techniques for crystallographic analysis. Adsorption studies were also performed with a balanced solution of hydroxyapatite exposed to different times, 48, 120 and 168 hours and concentrations 1 x 10(-5) M, 3 x 10(-5) M, 8 x 10(-5) M y 1 x 10(-4) M of pamidronate. Infrared and raman spectrometry were not conclusive due to technical bias, but X-ray difractograms showed pure hydroxyapatite crystals in an hexagonal system. At constant time, pamidronate concentrations were varied, showing after 48 hours of exposition, a slight growth in the 002 plane, an aleatoric behavior in 213 and a marked increase in 004. After 120 hours, 002 plane is steady with a net growth in 004 and 213. After 168 hours, the 3 mentioned planes grow in proportion to pamidronate concentrations, tending to enlarge the crystal shape. Plane 13 markedly grow with pamidronate 8 x 10(-5) M a 1 x 10(-4) M, which are biologically high concentrations. Potentiometric assessments, in the 1 x 10(-5) to 1 x 10(-4) M range of concentrations show that bisphosphonate was completely adsorbed to the crystals. Additional "in vivo" observations showed changes in bone powder crystals isolated from pamidronate treated young animals, involving a growing of planes 002 and 211, in samples from both epiphysis and diaphysis, regarding untreated samples. Changes were more evident at epiphysis. In mature rabbits, it was shown a decrease in basal plane 002 and growing at 210, 211 and 310 with a trend to enlarge the crystal shape in diaphysis and to shorten it in vertebrate spongiosa. The "in vivo" doses are equivalent to those used by Ferretti et al. in intact rats with pamidronate low dose groups, showing an improvement of bone material properties and stiffness. Thus, it may rather be lower than the "in vitro" used concentrations. In concordance with above experimental conditions it can be concluded that bisphosphonates exert morphological changes in hydroxyapatite crystals, in a dose dependent manner, at least when high concentrations are used. In addition, it is postulated that changes observed on "in vivo" samples may be the result with other adaptative factors as for example the local mechanical usage. The latter data were limited, and should be studied with more details if an extrapolation to the bisphosphonate treated osteoporotic women is intended. Finally, it is suggested that any agent that changes BMU activity (all known anti-osteoporotic drugs) may potentially modify the quality of hydroxyapatite crystals, affecting in turn the bone resistance to fracture, independently from the quantity of bone mass gained. Thus, to help predicting the consequences on skeletal fragility, there is a need to know the direct or indirect effect of drugs on bone crystals.

Animals↗
PubMed2002

Measurement of 4-hydroxynonenal in small volume blood plasma samples: modification of a gas chromatographic-mass spectrometric method for clinical settings.

4-Hydroxynon-2-enal (4-HNE) is one of the major aldehydic products of lipid peroxidation (LPO) and is involved in a number of pathophysiological processes. Since LPO products are useful indicators for oxidative stress in vivo, a number of detection methods for LPO products in biological tissues were developed. However, none of these methods is presently used in clinical settings. In order to introduce LPO products as biomarkers in clinical studies a suitable GC-MS method for 4-HNE detection was adapted to meet clinical requirements. As one result, the minimal sample volume could be decreased to 50 microl of plasma so that the method might even be suitable for pediatric purposes. The best internal standard (I.S.) for 4-HNE detection by GC-MS 9,9,9-D(3)-4-hydroxynon-2-enal was introduced by van Kuijk et al. [Anal. Biochem., 224 (1995) 420]. However, because of its limited availability, benzaldehyde-ring-d(5), 4-hydroxybenzaldehyde, and 2,5-dihydroxybenzaldehyde were tested to find an alternative. Out of these three, 4-hydroxybenzaldehyde was shown to serve best as I.S. To examine the applicability of the adapted method, tests on the stability of 4-HNE in samples during storage were carried out. It was shown that plasma samples need to be stored at -80 degrees C or less to avoid greater loss of 4-HNE. Samples with 4-HNE concentrations close to the physiological level were shown to be stable over 22 months at -80 degrees C. The introduction of a new and easily available I.S., reduction of the sample volume, and information about sample stability provided by this study facilitate 4-HNE determination in most clinical settings.

Aldehydes↗
PubMed2006

CE for cytokinin analyses: a review.

Analyses of cytokinins are very important in both plant physiological and biomedical research as they are implicated in many biological processes. Reliable, sensitive, selective and inexpensive methods that are flexible and designed for automation are required for these analyses. This review addresses the advances made in the separation and determination of cytokinins by CE as well as the other applications of CE (i.e., determination of dissociation constants and complexation constants of cytokinins). The various CE modes used to separate the compounds and the quantification strategies are examined. Special attention is also focused on those aspects that improve on the sensitivity and/or selectivity, such as sample extraction and preconcentration, on-line preconcentration techniques (stacking), and/or specific detectors (e.g., MS). With the coupling to the preconcentration techniques and certain detection systems, numerous CE methods can potentially be adapted for the analysis of cytokinins in complex biological samples. Therefore, we would anticipate wider applications of CE methods in the near future for cytokinin analyses, which should facilitate a decrease in analysis cost and should help to improve analysis efficiency.

Cytokinins↗
PubMed2006

Thermal tolerance of acid-adapted and non-adapted Escherichia coli O157:H7 and Salmonella in ground beef during storage.

Thermal tolerance of acid-adapted Escherichia coli O157:H7 or Salmonella in ground beef was evaluated during storage at 4 degrees C or -20 degrees C. Both pathogens were adapted to acidic conditions (pH approximately 4.6) by growing in tryptic soy broth supplemented with 1% glucose. A five-strain cocktail of E. coli O157:H7 or Salmonella was grown separately in TSB (pH approximately 6.6) and TSB + 1% glucose for 24 h at 37 degrees C to provide cells with or without acid adaptation. Irradiated ground beef was inoculated with either acid-adapted or non-adapted E. coli O157:H7 or Salmonella; the samples stored at 4 degrees C were subjected to heat treatment at 62 degrees C or 65 degrees C on days 1, 7, 14, 21, and 28, and the samples stored at -20 degrees C were subjected to heat treatment at 62 degrees C or 65 degrees C on days 1, 30, 60, 90, and 120. Decimal reduction time (D values) of the pathogens was determined as an indicator of thermal tolerance. Significantly higher D(62) values were observed on days 21 and 28 for non-adapted E. coli O157:H7 stored at 4 degrees C and on days 90 and 120 for non-adapted E. coli O157:H7 stored at -20 degrees C (P < 0.05). Higher D(62) values were observed on days 21 and 28 among non-adapted Salmonella strains stored at 4 degrees C and on day 28 for acid-adapted strains of Salmonella stored at 4 degrees C (P < 0.05). Higher D(62) values for acid-adapted strains of Salmonella stored at -20 degrees C were observed on days 30, 60, and 90 (P < 0.05), when while no differences were observed in the D(65) values of acid-adapted and non-adapted strains of E. coli O157:H7 and Salmonella throughout storage at both temperatures (P > 0.05). This suggests that acid adaptation of foodborne pathogens provides a certain level of protection against heat treatment at lower cooking temperatures, while at higher temperatures there were no observed differences between the sensitivity of acid-adapted and non-adapted strains in an actual food system over an extended period of refrigerated and frozen storage.

Adaptation, Physiological↗
PubMed1994

[Experience with the molecular genetical detection of the chimera gene of the Philadelphia chromosome].

Molecular genetical techniques could be developed for detection of the chimera gene of Philadelphia chromosome or that of its gene product, due to the relatively conserved structure of the chimera gene. The authors successfully analysed 123 blood/bone marrow samples from 106 patients using these molecular techniques adapted from the literature. Patients were classified by the first diagnosis, 65 CML, 7 AML, 13 ALL patients were studied. 12 patients had the diagnosis of myeloproliferative syndrome, and 9 patients were after bone marrow transplantation. 57% of the total, and by diagnosis, 74% of CML, 28% of AML, 54% of ALL, and 33% of post-transplant samples have shown the chimera gene structure characteristic for Philadelphia chromosome. All patients of myeloproliferative syndrome were negative. In some cases the authors had the opportunity to study simultaneously the peripheral blood and the bone marrow sample of the same patient and of the same date. The ratio of the positivity of the two samples varied from one to infinite. The authors could follow the effect of interferon in one case, the change of clonality of the leukemic cell line in an other case. They had the opportunity to detect two different abnormal gene structures in the sample of an AML patient.

Chimera↗
PubMedDate not supplied

[Minimal residual disease in acute myeloid leukemia in children--standardization and evaluation of immunophenotyping in the AML-BFM-98 study].

BACKGROUND: Minimal residual disease is a prognostic factor in AML. However, the impact on treatment stratification is not established. The AML-BFM 98 MRD study started in 1/2000 in order to evaluate, standardize and establish immunophenotyping in AML in children. METHODS: In a first phase the participating laboratories in Muenster, Goettingen, Vienna and Prague agreed on identical antibody-panels and standardized procedures of sample processing, analysis and data management. The consensus panel was evaluated and adapted to 3- and 4-color flowcytometry. The complete panel was applied to each follow-up sample in orderto minimize the risk offalse negative results due to the loss or shift of antigens during treatment, a known phenomenon in myeloid blasts. Between 1/2000 and 9/2001 165 of 198 protocol patients were analysed at diagnosis, in 149 children at least two follow-up samples were available. RESULTS: Three kinds of immunophenotypes could be defined. Asynchronous expression of stem cell and myeloid antigens i. e. CD34/CD117 combined with CD13/CD15 had a low specificity because precursors in regenerating or normal bone marrow expressed this pattern in 0.47 % (0.1 to 1.5 %). The aberrant co-expression of stem cell antigens and lymphatic antigens such as CD7 or CD2 showed a median level of specificity (0.07 % (0.04 to 0.19 %). Aberrant expression ofstem cell antigens combined with B-lymphatic (CD19, CD10) or NK-cell antigen (CD56) showed the best specificity. The maximal level in normal bone marrow was 0.05 %. Sensitivity of different immunophenotypes was evaluated by diluting known leukemic blasts in regenerating bone marrow. Minimal level of sensitivity was found to be at 10 (-3) to 5 x 10 (-4). According to these data highiy specific immunophenotypes could be detected in 33 %, median specificity was seen in 71 % and low specificity was seen in 88 % of the protocol patients. Two laboratories analyzed simultaneously 17 samples of children with AML from diagnosis and during therapy. A high correlation of blast quantification could be demonstrated (correlation r (2) = 0.98; blasts < 5 % r (2) = 0.91). In addition, two independent explorers quantified the raw data of 16 samples. All results correlated well (r (2) = 0.97; blasts < 5 % r (2) = 90.94). CONCLUSION: The prospective study phase, started 1/2002, aims to test the impact of MRD diagnostics as an independent prognostic factor in AML in children. This might facilitate future treatment stratification and consequently optimize outcome.

Adolescent↗
PubMed2005

Quantification of stratum corneum removal by adhesive tape stripping by total protein assay in 96-well microplates.

BACKGROUND/AIMS: Examination of stratum corneum (SC) content with tape stripping and a colorimetric method is increasingly used. We examined the possible use of microplates in tandem with a colorimetric method to examine SC removed with tape stripping. As a corollary to this examination, the homogeneity of tape strips was examined. METHOD: The commonly used Lowry assay was adapted for 96-well plates. Tapes were divided into four regions and sample disks of 5 mm diameter were taken from each and analyzed for SC mass using the adapted Lowry assay. RESULTS: Homogeneity of SC removal over different areas across a tape strip is limited. CONCLUSION: Quantification of SC by means of a 96-well microplate-based colorimetric method is feasible and shortens the time of analysis. However, when using D-Squame tape disks, SC removal on a limited area of the tape is not predictive for SC removal on the entire tape as removal is inhomogenous. Therefore, SC protein extraction should be performed on a large enough area, eventually on the entire tape when quantifying SC mass removed by tape stripping.

Adhesiveness↗
PubMed1987

Radial diffusion as a simple and rapid method for screening superoxide dismutase activity.

Superoxide dismutases are of great interest due to their increasing medical applications in therapy and diagnosis of some diseases. The radial diffusion assay was evaluated for its usefulness as a simple, cheap and accurate assay for screening superoxide dismutase activity. In this assay O2- radicals were generated from the interaction of reduced riboflavin with molecular oxygen upon exposure of agar gel containing riboflavin and N,N,N,N-tetramethylethylene diamine (TEMED) to light. If nitrotetrazolium dye is also present, it will be reduced to the blue insoluble formazan, whilst if superoxide dismutase is present it will prevent this blueing. The developed assay was found to give reproducible estimates of pure samples of superoxide dismutase with a lower limit of measurements of about 10 mg. It can be adapted to measure the levels of superoxide dismutase in various crude biological samples.

Animals↗
PubMed1994

Family stress, social support, violence, and sons' behavior.

Although the low income, female-headed, inner-city family has been repeatedly linked to child behavior problems, the family processes related to child misbehavior in this high risk group have not been identified. In a group of predominantly African American inner-city low-income mothers who lived alone with their children, the relationships between family stress, social support, mothers' conflict resolution tactics, and sons' behavior were examined using the family stress adaptation model, and potential nursing interventions were identified. The sample of low-income, inner-city mother-alone families reported more family stress and less social support than normative White Anglo-Saxon Protestant families. Family violence rates did not differ between the sample and nationally representative normative groups. Thirty-nine percent of sons, referred to the study because of school difficulties, were reported to have behavior problems requiring additional assessment. Analysis confirmed the fit of sample data to the model and identified family stress as the best site for nursing intervention for these high-risk families.

Adaptation, Psychological↗
PubMed2000

Measurement of soluble transferrin receptor by immunoturbidimetry and immunonephelometry.

OBJECTIVE: To evaluate and compare two new commercially available immunoturbidimetric and immunonephelometric assays for measuring soluble transferrin receptor (sTfR) in serum. To adapt the immunonephelometric assay to an automated chemistry analyzer. DESIGN AND METHODS: Total imprecisions and detection limits were calculated and compared. Fifty-six samples were used for methods comparison. The nephelometric assay was adapted to the Hitachi 911 analyzer. RESULTS: Both methods displayed acceptable imprecisions and detection limits. Their correlation was good but a proportional bias was observed. The adaptation of the nephelometric assay to the Hitachi 911 was successful. CONCLUSIONS: These two new immunoassays are analytically acceptable and more practicable than previously developed methods. The differences observed between both methods underscores the need for standardization. The nephelometric assay was easily adaptable to an automated chemistry analyzer.

Biomarkers↗