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[Legal aspects of biological sample banks].

In order to frame the research on the human biological products, the French legislator has chosen an option consisting in several laws. This situation represents serious difficulties for the researcher. In the first way he will have to apply various general principles corresponding to the protection of persons since the sampling. To these general principles it has to be add more specific rules related to sampling organisation. The complexicity of this system being the references to be taken by the researcher following the organisation level of the samplings. Consequently legislation has to be adapted at this particular subject: human research.

Bioethical Issues↗

Polymorphism of class I alcohol dehydrogenase in French, Vietnamese and Niger populations: genotyping by PCR amplification and RFLP analysis on dried blood spots.

The polymorphism of human alcohol dehydrogenase (ADH) can contribute to the explanation of the important ethnic differences towards alcohol metabolism. Its assessment at the genomic DNA level with a procedure, excluding labelled probes, consisting of PCR (Polymerase chain reaction) amplification on dried blood spots and analysis of allele-specific RFLP (Restriction fragment length polymorphism) profiles, is well adapted to extensive studies in population samples. It can emphasize the importance of ADH as a genetic marker of population. Three ethnic groups (French Caucasians, Vietnamese Orientals, Black Africans from Niger) were studied. ADH2 and ADH3 genotypes were in equilibrium according to the Hardy-Weinberg law. Important differences were noted in the distribution of ADH2 and ADH3 alleles.

Alcohol Dehydrogenase↗

Geographic distribution of lymphatic filariasis in Haiti.

Although lymphatic filariasis is known to have been endemic in Haiti since at least the mid 1700s, a national filariasis survey has never been conducted. As a first step in the national program to eliminate filariasis, we collected blood in January-April 2001 from 50-250 school children (6-11 years old) in all 133 communes of the country using an adaptation of the lot quality assurance sampling method. Of 22,365 children tested, 901 (4.0%) were positive for circulating Wuchereria bancrofti antigen. When weighted by commune population, the overall national antigen prevalence in this age group was 7.3%. Infected children were found in 117 (87.9%) communes, the most heavily affected areas being concentrated in the northern part of the country. In only 16 (12.1%) communes were all 250 children antigen negative. Thus, W. bancrofti infection in Haiti is much more widespread than previously realized; virtually the entire population of the country may be considered at risk of infection.

Animals↗

Survey of a pediatric hospital staff regarding cases of suspected child abuse and neglect.

BACKGROUND: The suspicion of child abuse and neglect may arise from manifestations such as physical or psychosomatic symptoms, eating disorders, suicidal behavior, impaired parental functioning, etc. Thus the arrival of an abused or neglected child at the hospital provides an opportunity for detecting the problem and beginning a process of change. Optimal utilization of this potential depends on the awareness, diagnostic ability and cooperation of the staff. OBJECTIVES: To assess knowledge about hospital policy, attitudes and actual behavior of hospital staff in cases of SCAN. METHODS: The questionnaire was adapted and distributed to a convenience sample of personnel at a children's hospital. The questionnaire included items on knowledge of hospital policy regarding SCAN, attitudes towards inquiring about cases that appear suspicious, and behaviors in cases in which the respondent was involved. The comparison of responses to specific questions and among members of different professions was analyzed by chi-square test. RESULTS: Eighty-two staff members completed the questionnaires. Most of the respondents were aware of hospital policy regarding suspected abuse (86.6%), with fewer regarding suspected neglect (77.2%). Physicians were the least aware of these policies, as compared to medical students, nurses and social workers. Although most considered the issue of SCAN a responsibility of members of their own profession, 35.4% considered it primarily the responsibility of the welfare or judicial systems. Over 40% felt uncomfortable discussing suspicions with the child and nearly half felt uncomfortable discussing them with parents. The most often reported reason for this was the sense that they lacked skills or training for dealing with the issue. Despite this, when asked about actual behavior, 94.7% responded that they do try to clarify the circumstances related to the suspicious symptoms. Respondents were more likely to contact the hospital social worker than community resources (91.5% vs. 47.2%). CONCLUSIONS: There is a need to encourage awareness, discourse and training of medical personnel regarding SCAN in order to maximize their potential to identify children at risk.

Adult↗

Dental contribution to paleo-odontological study of interarch relations in a human fossil.

In paleo-anthropology the fragility of fossil pieces (teeth and supporting bones) reduces their possible manipulation when studying the interarch relations. Two original impression methods of the jaw pieces are proposed, both adapted from those currently practiced in odontology. The plaster replicas of the dental occlusal parts are prepared according to the manufacturing procedures used in prosthetic dental laboratories. This study led to the following observations: 1) the impression techniques used by odontologists are adapted to the moulding of fragile samples. 2) The replicas elaborated from these mouldings made easier the cast manipulation in confrontation. 3) Macrophotography is a complement to direct observation of the pieces and their replicas. 4) For paleoanthropologic purposes, such studies can be easily carried out on almost any animal or human fossils.

Cameroon↗

Uncertainty and adjustment during radiotherapy.

The relationships among uncertainty, hope, symptom severity, control preference, and psychosocial adjustment were examined in persons having radiotherapy for cancer. After 15 days of radiotherapy, both uncertainty (17%) and hope (16%) explained significant amounts of the variance in adjustment. At the end of treatment, uncertainty (18%), hope (11%), and symptom severity (7%) all significantly increased the explained variance in adjustment. Greater uncertainty and less hope were associated with more adjustment problems; symptom severity increased the explanation of adjustment difficulty at treatment completion. There was no evidence that uncertainty had positive effects in this sample. Findings also showed that control preference was unrelated to the concepts of interest in this sample.

Adaptation, Psychological↗

A commercial enzyme immunoassay method (EMIT) compared with liquid chromatography and bioassay methods for measurement of chloramphenicol.

A new enzyme immunoassay method (EMIT; Syva Co.) was compared with conventional high-performance liquid chromatography (HPLC) and agar-diffusion bioassay methods for measurement of chloramphenicol in human serum. Forty-nine serum samples were assayed by each of the three methods. Excellent correlation was observed between values by EMIT and by the two conventional methods (r = 0.986 and 0.961). Precision was acceptable (CV less than 5%) with EMIT. Assay of samples containing chloramphenicol glucuronide and chloramphenicol succinate demonstrated that EMIT recognizes only the biologically active (base) form of the drug. The capability to test serum samples as small as 0.2 mL, adaptation to widely available instrumentation, and provision of rapid results are principal advantages of the EMIT method for routine chloramphenicol measurements.

Biological Assay↗

The use of immobilized enzyme reactors in continuous-flow analyzers for the determination of glucose, urea, and uric acid.

We describe the use of immobilized enzymes in assay methods for the determination of glucose with glucose oxidase, uric acid with uricase, and urea with urease in serum samples. The enzyme reactor tubes were adapted to continuous-flow analyzers (Technicon AA II, SMA 12/60, and SMAC) used in routine laboratory determinations, and results with their use were compared to those from assays involving soluble enzymes. We substituted the reactors for the free enzyme reagents in the respective channels of the SMA 12/60 and SMAC, without modifying the parameters of the remaining channels. We compared assay sensitivity, precision, and carryover for immobilized and conventional liquid enzymes. Immobilized enzyme reactors provide accurate, reliable, convenient, and economical alternatives to the use of free enzyme reagents in these systems.

Autoanalysis↗

Optimized liquid-chromatographic determination of metronidazole and its metabolites in plasma.

Metronidazole and its known metabolites in plasma can be rapidly separated by a "high-pressure" liquid-chromatographic method that can also be adapted for rapid determination of tinidazole. Samples deproteinized with trichloroacetic acid (50 g/L final concentration) undergo isocratic separation on a reversed-phase C18 column eluted with an 8/92 (by vol) mixture of acetonitrile/KH2PO4 (5 mmol/L, pH 3.0). The method is sensitive, reliably detecting as little as 25 micrograms of metronidazole and (or) its metabolites per milliliter of plasma. The detector response varied linearly with concentration for all compounds tested over a wide range (25-500 micrograms/L). Within-day and between-day variation was generally less than 2.5% for all concentrations of all compounds tested. Various other antibiotics tested did not interfere.

Chromatography, High Pressure Liquid↗

Measurement of volatile fatty acid disappearance and fluid flux across the abomasum of cattle, using an improved omasal cannulation technique.

Six steer calves, surgically fitted with a permanent cannula in the rumen, omasoabomasal orifice, abomasum, and duodenum were used to determine total digesta flow and volatile fatty acid (VFA) concentration at various points in the digestive tract. The omasoabomasal cannula had a flexible nylon sleeve that could be exteriorized through the abomasal cannula to collect omasal effluent. Three experiments were conducted: 95% concentrate fed at maintenance (2,670 g of organic matter intake/d); 95% concentrate fed ad libitum (3,484 g of organic matter intake/d); and brome hay fed ad libitum (2,927 g of organic matter intake/d). Calves were offered the diet in 12 portions daily. Each experiment included a 14-day adaptation period and a 2-day sample collection period during which chromic oxide was used as a digesta flow marker. In all 3 experiments, VFA concentration was greatest in the rumen sample (84 to 109 mM), intermediate in the omasal sample (32 to 40 mM), and lowest in the duodenal sample (7 to 14 mM, P < 0.01). Total fluid flow at the duodenum was 13 to 18 L/d greater than flow at the omasum (P < 0.10). Omasal VFA flow was twofold greater than duodenal VFA flow (P < 0.05). There was a net fluid increase and net disappearance of VFA across the abomasum. The cannulation technique was useful for repeated collection of omasal effluent for at least 3 months.

Abomasum↗

Use of urease-bromothymol blue-agar method for large-scale testing of urine on grain and seeds.

The current AOAC method (963.28) for large-scale (50 g) testing of urine on grain is based on the reaction of sodium in urine with magnesium uranyl acetate. Detection of sodium suggests that urine is present and that a test for urea is appropriate. Urea is detected with urease-bromothymol blue-paper and is confirmed through its reaction with xanthydrol to form dixanthylurea crystals, which are detected microscopically. The initial nonspecific test for sodium can be influenced by the presence of salt or other sodium compounds. Furthermore, the magnesium uranyl acetate spray used in Method 963.28 potentially exposes the analyst to the aerosol of a volatile, toxic uranium compound. Excess reagents and analyzed test portions must be disposed of as radioactive waste. In addition, Method 963.28 requires several steps to determine the presence of urea. The alternative AOAC method (972.41) tests for the presence of urea from urine on individual seeds. Urea is enzymatically decomposed to ammonia and carbon dioxide by urease. Liberated ammonia shifts the pH, changing the color of the indicator in the agar from yellow to blue. This study adapts Method 972.41 to larger test samples. Up to 25 g grains and seeds are sprayed with urease test agar instead of being individually immersed in the urease test agar. The modified method was used to analyze urea on seeds and grains of 24 plants from 4 families. The method has a limit of detection of one seed contaminated with 1 microgram urea.

Aerosols↗

Improved methods for quantification of human immunodeficiency virus type 1 RNA and hepatitis C virus RNA in blood using spin column technology and chemiluminescent assays of PCR products.

The quantification of human immunodeficiency virus type 1 (HIV-1) RNA or hepatitis C virus (HCV) RNA has been facilitated by adapting a spin column procedure for sample preparation and the use of chemiluminescent detection of polymerase chain reaction (PCR) products in microtiter plate format. All materials were commercially available and relatively inexpensive. By making a single dilution prior to amplification, concentrations of 500 copies to 2.5 million HIV-1 1 RNA copies per mL and 1,000 copies to 50 million HCV RNA copies per mL could be determined on 140-microL samples. Between-run imprecision employing the improved procedure for HIV-1 RNA was 23%. Correlation of HIV-1 RNA concentrations obtained using chemiluminescent detection with values obtained by colorimetric assay of PCR products was 0.98. Correlation of HCV RNA concentration determined by the spin column-chemiluminescent assay procedure with those obtained by branched DNA methodology was 0.91. Spin columns could be used with serum or plasma containing acid-citrate-dextrose or heparin anticoagulant, but heparinized samples required treatment with heparinase prior to amplification.

Anticoagulants↗

[The perinatal situation in France. Trends between 1981 and 1995].

OBJECTIVES: Assess the main indicators of health status and medical practice at delivery and to determine the feasibility of a routine national survey. POPULATION AND METHOD: A survey conducted in 1995 concerned all live births and stillbirths occurring within one week. The sample included 13,147 women in metropolitan France. The results were compared with those of earlier national perinatal surveys. RESULTS: Since 1981, the perinatal situation in France has shown a rise in maternal age at delivery, development of prenatal care (particularly the number of visits), and an increase in the number of procedures at delivery, notably induction. The preterm delivery calculated for all births has remained unchanged: 5.6% in 1981 and 5.9% in 1995, but the proportion of infants weighing less than 2500 g has increased from 5.2% to 6.2%. CONCLUSION: The 1995 national perinatal survey in France, based on all births during one week and involving minimal data collection has provided a representative sample of births and information well adapted to surveillance of the main health and medical practice parameters. This type of survey should become routine and serve as a basic element for epidemiological surveillance.

Adult↗

Enhanced detection of lipoprotein lipase by combining immunoprecipitation with Western blot analysis.

This manuscript describes the problems inherent in combining immunoprecipitation of lipoprotein lipase (LPL) with its detection by Western blot, and how these problems can be circumvented by the preparation of suitable immunoreagents. These reagents used during the immunoprecipitation step, include Fab fragments of the primary antibody (chicken anti-bovine LPL), and a covalently linked immunomatrix of the secondary antibody (rabbit anti-chicken IgG). The use of these reagents in conjunction with Western blot detection virtually eliminates the problem of non-relevant protein detection when analyzing LPL from complex biological samples. Moreover, this approach can be adapted to detect any protein with the same inherent problems as LPL, such as hepatic lipase.

Animals↗

The use of a diffusion test for the detection of antibiotics in the tissues of slaughter stock.

The Brilliant Black Reduction Test Kit (BR Test), which is widely used to detect antimicrobial residues in milk, was adapted to detect residues in the meat and tissues of slaughter stock. The adaptation consisted of placing kidney and muscle tissue samples into 2.5ml diffusion cups containing 0.4ml media plus Bacillus stearothermophilus spores and brilliant black indicator. A preliminary trial undertaken to test the lower limits of sensitivity of the adapted BR Test to a number of the more common antibiotics used in food animals, was followed by a survey involving 943 pigs slaughtered at one abattoir. Samples were tested from 87 suppliers of which 11 regularly marketed pigs with detectable antimicrobial residues. Most of these pigs came from large pig producing units. Three suppliers marketed pigs with suspicious reactions. No residues could be detected in pigs from the remaining 73 suppliers. The BR Test was found to be a quick, inexpensive, practical screening test which could be utilized for the routine detection of antimicrobial residues in slaughter stock at all South African abattoirs.

Abattoirs↗

Measuring acid volatile sulphide in floodplain lake sediments: effect of reaction time, sample size and aeration.

For the routine measurement of acid volatile sulphide (AVS) in floodplain lake sediments, an earlier published diffusion method was adapted and optimised. We evaluated the effect of reaction time, sample weight and passive sample aeration on AVS recovery, and determined the method's reproducibility. The optimal reaction time was 4 h. Losses of AVS due to sample aeration did not occur within 15 min of sample-air contact. Relative standard deviation was <2.5% for known sulphide solutions, was between 10% and 15% for AVS concentrations in sediments and <12% for SEM concentrations in sediments, generally. Sediment samples with known SEM and AVS content were used to compare results of the developed method with the purge-and-trap method. There is a good agreement with the purge-and-trap method for SEM concentrations. AVS concentrations measured with the diffusion method are higher than with the purge-and-trap method. We conclude that the adapted diffusion method is well suited for the routine measurement of AVS concentrations in floodplain sediments.

Environmental Monitoring↗

Does help help? The adaptive consequences of obtaining help from professionals and social networks.

This study reports on a longitudinal analysis of changes in adaptation associated with seeking help on a representative sample of Chicago area adults who had experienced one of three transitions or four crises during the interval between 1972 and follow-up 1976--77 interviews. For each event, respondents are classified into three groups according to their help-seeking behavior: those who went to professionals, those who went only to their social networks, and those who had the event but sought no help. Nine measures of adaptation are used: symptoms of anxiety and depression and strains and stresses in four role areas. Statistical controls equate the groups on demographic characteristics, perceived stress, personal resources, access to help, and elapsed time since the event. There are no consistent statistical significant differences among the groups. No evidence is found that help-seeking has positive adaptive consequences. The findings are not likely to result from an inadequate sample, outcome measures, or statistical controls, but could result from insufficient information on the kind, quality, and duration of the help provided.

Adaptation, Psychological↗

Electrochemical determination of femtomole amounts of free reduced and oxidized glutathione. Application to human hair follicles.

A simple and sensitive high-performance liquid chromatographic technique has been developed for the quantification of free reduced and free oxidized glutathione in biological samples. After acidic extraction and isocratic separation of the compounds of interest on a reversed-phase column, both forms of glutathione are quantified with a coulometric detector working in the oxidative mode. The limit of detection is 125 fmol for reduced glutathione and 400 fmol for the oxidized form (signal-to-noise ratio of 3). This sensitivity allows the measurement of the small amount of glutathione present in a single hair follicle. The technique is well adapted to microsamples, i.e. for non-invasive sampling technique (hair, skin, tears, etc.) and can be adapted to various cells or tissues.

DNA↗