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PubMed2006

[The Portuguese version, cross-cultural adaptation and validation of specific quality-of-life questionnaire -AQUAREL - for pacemaker patients].

OBJECTIVE: To translate, to make the cultural adaptation and to evaluate reproducibility and validity of the Portuguese version of the AQUAREL (Assessment of QUAlity of life and RELated events) questionnaire, which is a specific tool to assess quality of life in pacemaker patients. METHODS: We evaluated 202 pacemaker patients: 63 patients during the cross-cultural adaptation stage and 139 during the reproducibility and validity evaluation stages. The questionnaire translation was reviewed repeatedly until > or = 85% of patients correctly understood the questions. Reproducibility of the final version was tested in 69 patients in whom the interview was performed twice by the same researcher. Validity was checked by the correlation between scores obtained in AQUAREL domains and those obtained in SF36 domains, in the functional class and the distance walked in the six-minute test. RESULTS: The internal consistency of AQUAREL was adequate, with Cronbachs alpha coefficient varying between 0.59 and 0.85. Reproducibility was good, with high correlation coefficients (0.68-0.89) and random distribution of data in Bland and Altman plots, without systematic bias. A significant association was observed among AQUAREL domains and those obtained in SF36 domains and the functional class (p<0.01), although significant correlations with the distance walked in the six-minute test were not found. CONCLUSION: The Portuguese version of the AQUAREL questionnaire is easy and rapid to apply, and could be used as a specific questionnaire to assess quality of life in pacemaker patients.

Adolescent↗

PubMed1990

[Screening of blood donors for anti-HIV-1].

Repeatedly reactive results (also with reproducibility from donation to donation) are found in normal blood donor screening. They are obviously not HIV-1- (and/or HIV-2) specific. In some cases it cannot be clarified if we have to face a seroconversion. The cause of some antibodies (e.g. isolated p17 and/or p24 and/or p55) is not yet known. Therefore we cannot decide whether these results could be neglected or have to be considered a serious risk of transfusion associated infection.

AIDS Serodiagnosis↗

PubMed1988

Effect of a single dose of mesoglycan on the human fibrinolytic system, and the profibrinolytic action of nine daily doses.

The profibrinolytic activity of orally administered Mesoglycan was evaluated in 18 patients affected by impaired plasma fibrinolytic activity. Mesoglycan was administered by a single oral dose of 24, 48 or 72 mg on 1 day, and by repeated doses of 48 mg twice a day for 9 consecutive days. After the single administration all the fibrinolytic parameters were significantly and positively influenced with an order of magnitude and a duration of effects proportional to the dose employed. After the repeated administration, a constant and reproducible activation of the fibrinolytic system was observed without any interference with haemocoagulative parameters. These results confirm that Mesoglycan is endowed with a relevant profibrinolytic activity in man after oral administration. The pharmacological activity of Mesoglycan could possibly involve the liberation of a certain amount of plasminogen tissue activator.

Administration, Oral↗

PubMed1986

Trifluoperazine inhibits thyrotropin-releasing hormone-stimulated TSH secretion.

In previous work changes of the thyrotropic secretion after administration of some substances affecting the calcium content in the cytosol were demonstrated. The object of the present investigation was to assess the hormonal response to the administration of trifluoperazine, a psychopharmaceutical preparation, the main mechanism of its action being the inactivation of the cytosol receptor for the calcium signal - calmodulin. The poor utilization of intracellular calcium of the secretory cell is then the factor which inhibits secretion proper. The thyrotropic secretory reserve (delta TSH) was assessed in the same subjects before and after trifluoperazine administration by the TRH test as the difference of values at rest and TRH-stimulated TSH levels during the 20th, 30th, 40th and 60th minute following intravenous administration of 200 micrograms TRH. It was revealed that this calmodulin antagonist administered for one week in amounts of 6-12 mg per day by mouth significantly inhibits the secretory response of TSH to TRH in healthy subjects during the 20th and 40th min. (P less than 0.05). The reproducibility of the TRH test repeated in a group of subjects not treated with trifluoperazine, however, under equal conditions and after the same time intervals as in the experiment with trifluoperazine was very satisfactory and thus physiological inhibition caused by repeated TRH administration could be ruled out. The inhibition of the secretory TSH response to TRH can be therefore considered the consequence of the direct effect of trifluoperazine on the thyrotropic secretory mechanism. Trifluoperazine significantly reduced serum calcium levels and raised phosphate levels, while it did not affect the blood levels of magnesium.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1988

Urodynamic investigations in healthy fertile females during the menstrual cycle.

Ten healthy, fertile women were investigated three times during the menstrual cycle in order to study a possible hormonal influence on the urodynamic parameters. On each occasion three urethral pressure profiles were recorded, and cystometry was carried out both in the supine and sitting position followed by pressure-flow studies. No significant changes attributive to menstrual cycle hormonal changes were observed in the profilometry data, the cystometric parameters or in the pressure-flow parameters. Both the short and long term reproducibility of the three times repeated urodynamic parameters were good. Measurements performed regardless of time in the menstrual cycle are thus representative in normal women.

Adult↗

PubMedDate not supplied

His-Purkinje waveforms on externally recorded averaged unfiltered electrocardiograms.

Electrocardiographic signal recorded in right unipolar leads (2V1, 3V1, V1) was amplified (up to 500,000 times) averaged (256 or 512 cardiac cycles) and finally digitally filtered, in order to record His-Purkinje (HP) activity. A group of 41 patients with sinus rhythm and PR intervals ranging between 100 and 250 ms was repeatedly investigated. Distinct and highly reproducible waveforms located in the PR segment, attributable to HP activity, were recorded on the averaged unfiltered traces in 14 patients (34%). Waveforms, with an amplitude ranging between 4 and 80 microV, were positive in 13 patients and negative in one. In one patient, with atrial tachycardia with 2:1 atrioventricular block, two positive successive deflections suggested the possibility of recording the proximal and distal His activity. Externally recorded averaged unfiltered traces could be useful for the investigation of HP activity in a relatively large proportion of patients.

Angina Pectoris↗

PubMed1985

Hyperinflation, hyperventilation, and hyperoxygenation before tracheal suctioning in children requiring long-term respiratory care.

The findings reported failed to support a best method of pretreating subjects before tracheal suctioning to minimize oxygen desaturation. Conversely, all methods prevented significant desaturation. No subject's desaturation readings dropped during the study to such a point that they did not subsequently recover after 30 seconds and return to baseline by the end of the 20 minutes. Several subjects had oxygen saturation readings in the high 70s to low 80s as reported during CTP. After recovery from CTP ( in mot cases a 30-second time period), no clinically significant desaturation was noted from the 30-second time period to the end of the study. The results could not be reproduced when the trials were repeated on four subjects. If oxygenation is questionable, these children should be monitored noninvasively to prevent serious desaturation in an already compromised patient.

Bronchopulmonary Dysplasia↗

PubMedDate not supplied

Thin layer chromatographic method for determination of deoxynivalenol in wheat: collaborative study.

A collaborative study of a rapid method for the determination of deoxynivalenol (DON) in winter wheat was successfully completed. The method involves sample extraction with acetonitrile-water (84 + 16), cleanup using a disposable column of charcoal, Celite, and alumina, and detection by thin layer chromatography after spraying with an aluminum chloride solution. Each of the 15 collaborators analyzed 12 samples, 2 of which were naturally contaminated, and 10 to which DON was added, in duplicate, at levels of 0, 50, 100, 300, and 1000 ng/g. Average recoveries of DON ranged from 78 to 96% with repeatabilities of 30-64% and reproducibilities of 33-87%. The results of the study show that false positives were not a problem and that all of the analysts could detect DON at the 300 ng/g level or higher. The method has been adopted official first action.

Chromatography, Thin Layer↗

PubMed1985

Kinetics of In-111-platelets in the baboon: I. Isolation and labelling of a viable and representative platelet population.

A fully representative and viable platelet population was isolated from the blood of 15 baboons by a multiwash procedure, and labelled with In-111-oxine. The recovery of the total platelet population in the circulation was 85% +/- 9. Mean platelet life span was 146 hr +/- 13. Correcting for plasma radioactivity (always less than 3.5%) did not significantly affect the estimate of platelet life span (145 hr +/- 16) or recovery (85% +/- 12). Platelet survival estimates, repeated at different times, were reproducible. In 5 baboons, platelets were also harvested by a single step differential centrifugation. The mean life span of a representative platelet population was significantly longer than that of platelets harvested by a single step. Recovery values of the representative and non-representative population were similar. We conclude that it may be important to harvest and label a fully representative platelet population for kinetic studies. The proposed method is simple and reproducible, and may be applied in studies in humans.

Animals↗

PubMed1970

[Electrolytes in bovine intrauterine secretions in infertility sine material].

Serum and uterine secretions Na, K, Ca, Mg and P were studied in 15 normally reproducing and in 15 repeat-breeder cows. No cyclical variations were noted for these elements in the serum whereas the normal group showed cyclical and significant K, Mg and P variations (P <0.05) in the uterine secretions. The concentration of the studied uterine elements, with the exception of P, correlated with the concentration of their homologue in the serum at different stages of the cycle. It is believed that the concentration of serum Na, K, Mg and Ca maintains the intrauterine concentrations at the physiological level for the survival of the gametes and the embryo. Significant differences in the uterine concentrations of Na, K and P were noted between the groups at different stages of the cycle. These various concentrations as well as the nonsignificant variations of the uterine secretions might explain the infertility in the abnormal group.

Animals↗

PubMed1979

Modified method for carbadox in feeds: collaborative study.

The official first action method for carbadox in swine feed, 42.C01-42.C04, was modified in 2 respects. First, the samples were leached overnight at room temperature instead of boiled for 1 hr. This change avoided problems with overheating and excessive evaporation. Second, the dilution scheme for samples spiked with carbadox standard solution was changed to give absorbance values that were within the optimum working range of all types of spectrophotometers. The modified procedure was collaboratively studied by 21 laboratories. The repeatability standard deviation (sigma0) and reproducibility standard deviation (sigmax) were sigma0 = 0.00029% and sigmax = 0.00056% (8.9% of grand mean) for feeds containing 0.00617% carbadox; and sigma = 0.0012% and sigmax = 0.0019% (9.3% of grand mean) for feeds containing 0.0198% carbadox. The between-laboratory variance ratio was significant for feeds containing 0.0198% carbadox. The mean per cent of intent values for feeds containing 0.00617% carbadox and 0.0198% carbadox were 102% and 104%, respectively. In general, the statistical results were comparable to those previously obtained for the official first action method. Consequently, the modified procedure is not recommended as a replacement for the official first action method.

Animal Feed↗

PubMed1982

Recovery of eggs of two parasitic nematodes, Ascaris sp. and Trichuris sp.: Interlaboratory study.

An interlaboratory study was conducted to determine the effectiveness of the Nacconol ether centrifugation method for recovering parasitic nematode eggs from 3 contaminated products: a crop (cabbage), a sludge fertilizer (Milorganite), and a sewage effluent (Minneapolis). Six replicate samples for each of the 3 products were seeded with eggs at 3 different levels: 200 Ascaris suis and 8 Trichuris muris; 15 A.suis and 15 T.muris; 8 A.suis and 180 T.muris. Recovery was low for all samples except sewage effluent, in which recoveries greater than 100% in 2 samples resulted from the misidentification of arthropod eggs as Ascaris sp. The average mean percent recovery for the other samples was 22.53. Repeatability for replicate samples and reproducibility of results by individual laboratories were poor, and the method is not recommended for quantitative estimates of nematode egg contamination of foods and food-contact materials. However, the Nacconol ether centrifugation method can be used as an all-or-none test. (Only 13% of 1146 counts were falsely negative.) Of 69 samples, only 4 were falsely negative for A.suis eggs and only 1 was falsely negative for T.muris eggs in counts of 6 replicates.

Animals↗

PubMed1982

[Evaluation of gallbladder volume and motility with echotomography].

The gallbladder volume has been evaluated in 22 normal volunteer subjects (12 men and 10 women) by the real time ultrasound B scanning, using the formula V = 1/6 abc (a = length; b = width, c = antero-posterior diameter). The fasting GB volume, the residual GB volume after Bronner's meal (every 15 min. for 90 min.) and the maximum emptying (%) were evaluated in each subject. It was not observed any statistically significative difference between the two groups (fasting volume: 18.5 +/- 6.0 ml in men and 15.2 +/- 5.1 ml in women; residual volume: 4.3 +/- 1.5 ml in men and 3.5 +/- 1.3 ml in women). The maximum GB emptying in women occurs later. In order to verify its reproducibility, the experience has been repeated in two different days in seven men without any statistically significative difference.

Adult↗

PubMed1980

The effect of pindolol and salmon calcitonin on experimental gastric ulcers in rats.

Many different experimental models for the induction of gastric ulcers have been reported in rats. Most of these experimental designs are often not reproducible and the interpretation of the results obtained is sometimes difficult. In the present study, three different models were found to give reliable and reproducible results, which could be repeated at any time of the year with different experimenters performing the procedure. To date, these methods are in our opinion, the best in designing gastric ulcer experiments and assessing the effect of pharmacological active substances. Two pharmacological active substances were investigated in the present study, pindolol, a beta-blocking agent with intrinsic sympathomimetic activity and salmon calcitonin, a hormone influencing calcium homeostasis in blood. Using all three different models no effect was seen after pindolol administration, while a strong inhibitory effect on the formation of gastric ulcers was observed after salmon calcitonin. Following ligation of the pylorus, the ulcer formation rate was significantly decreased from 80 to 33% with a significant fall in ulcer index from 2 to 0.42 and reduction of the ulcer areas from 6.6 to 0.58 mm2 (p less than 0.05). In addition, following phenylbutazone administration the appearance of gastric ulcers was diminished after salmon calcitonin from 1.4 to 0.43 and in ulcer area from 4.5 to 0.95 mm2 (p less than 0.01). These three ulcer models used in the present study were found to be very reliable as compared with other models reported in the literature and tested in our laboratory.

Animals↗

PubMed1994

Quantitative measurement of vibratory perception threshold using a new vibrometer TM-31A.

The need for standardization and validation of quantitative tests for vibratory sensitivity has been increasingly recognized. Conventional vibrometers have been of limited use for the assessment of vibratory perception threshold (VPT) due to wide intraindividual variations. This study describes the determination of VPT for the medial malleolus (MM), the styloid process of the radius (SPR), and the pulp of the index finger (PIF) in normal subjects, using a new vibrometer, the TM-31A. This apparatus expresses results in terms of actual vibration amplitude and has a feedback mechanism that avoids damping of the stimulator in tissue. Repeated VPT measurements revealed good reproducibility of the test. The intraday and day-to-day variations of VPT were fairly small. VPT was found to differ significantly among sites (MM > SPR > PIF). The distribution in MM was substantially log-normal, whereas the SPR and PIF were normal. VPT values on each site correlated with advancing age, especially on the MM. It is concluded that TM-31A provides a reliable and valid assessment of VPT and contributes to the standardization of VPT testing.

Adult↗

PubMed1993

Variability in response to NSAIDs: what progress?

Little further work has established the nature and importance of variability in response to NSAIDs despite the phenomenon being identified by Huskisson in 1976. The following questions remain unanswered: the proportion of individuals who display marked variability in responses to different NSAIDs; reproducibility of individual responses over repeated exposures; the influence of various musculoskeletal disorders on the level of variability in response; and the importance of pharmacokinetic or pharmacodynamic mechanisms. Data continue to accumulate that there is a weak relationship between concentration of NSAIDs in plasma and degree of efficacy in RA and now OA and acute pain states, as well as with the incidence of toxicity, notably GI bleeding. The efficacy relationship may resemble a rectangular hyperbola with a steep slope upwards. None of the proposed mechanisms of action of NSAIDs additional to the universal ability to inhibit prostaglandin synthesis, which have been suggested as possible causes of response differences between drugs, has been linked rigourously to responses in individual patients. Systematic work linking clinical responses to pharmacokinetic parameters and pharmacodynamic mechanisms is required to understand variability of responses to NSAID therapy.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMedDate not supplied

Determination of metals in foodstuffs by atomic absorption spectrophotometry after dry ashing: NMKL interlaboratory study of lead, cadmium, zinc, copper, iron, chromium, and nickel.

An interlaboratory study of a method for determination of lead, cadmium, zinc, copper, iron, chromium, and nickel in foodstuffs by atomic absorption spectrophotometry (AAS) after dry ashing at 450 degrees C was conducted in 16 laboratories. The study was preceded by a practice round of familiarization samples and another round in which solutions were distributed and the metals were determined directly by AAS. The study included 5 different foods (liver paste, apple sauce, minced fish, wheat bran, and milk powder) and 2 composite diets. A single analysis was carried out on each sample. Suitable sample combinations were used as split level combinations for determination of the repeatability standard deviation. The relative reproducibility standard deviation for each of the elements ranged as follows: lead, 74-18% at 0.025-0.28 mg/kg; cadmium, 80-11% (0.002-0.51 mg/kg); zinc, 12-7% (44-72 mg/kg); copper, 47-10% (0.48-41 mg/kg); iron, 35-9% (2-228 mg/kg); chromium, 48-21% (0.008-0.22 mg/kg); nickel, 64-39% (0.025-0.39 mg/kg).

Dairy Products↗

PubMed1996

Oral idarubicin pharmacokinetics--correlation of trough level with idarubicin area under curve.

Idarubicin is the first anthracycline that can be successfully administered via the oral route and thus may facilitate antineoplastic chemotherapy at an improved quality of life. These perspectives are somewhat hampered by the large variation in bioavailability between individual patients and the obvious requirement to monitor plasma concentration and area-under the curve values (AUC) for an appropriate adjustment of idarubicin dose. In this study we describe the pharmacokinetics of idarubicin and its main metabolite idarubicin in 12 patients after oral application of 20 mg/m2 idarubicin on 3 consecutive days and demonstrate that the 24-h trough levels shows high correlation with AUC and may thus allow a rapid and easy determination of individual drug concentrations and an appropriate dose adjustment. The average terminal half-life was 30.5h for idarubicin and 66.9 h for idarubicinol. The AUC for idarubicin and its main metabolite idarubicinol revealed a substantial interpatient variation with AUC values ranging from 25.7 to 114 ng x h/ml (average 58.1 ng x h/ml) for idarubicin and from 109.4 - 445.2 ng x h/ml (average 287.3 ng x h/ml) for idarubicinol. However, the ratio of idarubicin/idarubicinol differed only two-fold from 1:3.7 to 1:7.7 with an average of 1:5.1. Both idarubicin and idarubicinol concentrations were highly reproducible, however, upon measurements after repeated applications within individual patients. Moreover, idarubicinol and idarubicin AUCs showed a good correlation with r=0.78, indicating that the interindividual variations of idarubicin AUC reflects differences in absorptions rather than metabolism. In order to describe the interindividual bioavailability of idarubicin - represented by AUC - measurement of a single data point with a high correlation with the AUC would be ideal. Our study demonstrates that the 24-h trough level shows such an excellent correlation (r=0.96) with AUC, making it the perfect candidate for fast estimates of the individual bioavailability in a given patient. On this basis, the longitudinal measurement of the 24-h trough level may allow the assessment of the impact of interindividual variations in AUC of clinical outcome and toxicity.

Acute Disease↗