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PubMed2001

Exercise testing in special populations: athletes, women, and the elderly.

Exercise testing in special populations such as athletes, women, and the elderly requires additional considerations from the clinician. Different protocols, as well as special accommodations, may be necessary for performing the test. Symptomatic athletes may have a number of cardiac conditions that lead to ischemic changes on the exercise test. Asymptomatic athletes often use serial exercise testing to evaluate the efficacy of training programs. For women and the elderly, assessment of risk factors and evaluation of symptoms are important considerations before performing the exercise test. Negative exercise test findings suggest a low risk for future cardiovascular events. Positive exercise test findings must be interpreted in light of the individual's pre-test probability. Assessment of the needs of these patients allows the clinician to tailor the exercise test to produce useful information.

Adult↗
PubMedDate not supplied

Chronic effects of gastroduodenal surgery on glucose and insulin response to oral glucose tolerance test in a population study.

Oral glucose tolerance test (OGTT) results were compared between 4,667 middle-aged males attending a preventive medical screening and intervention program in Malmö and the subjects in this sample who reported a history of previous operation for gastric or duodenal ulcer (n = 158, or 3.4%). 76% of the operated subjects were smokers in comparison with 50% in the general cohort of males of the same age. The glucose and insulin responses in the OGTT in both the smoking and non-smoking operated cases showed higher early peak values and a subsequent rapid drop of the levels with lower 120-min values of both glucose and insulin compared to the average screening cohort. This type of response to an oral glucose load had previously been well known in the acute and immediate postoperative stages of gastric and duodenal resection, but it had not been shown before that it seems to be a permanent effect and may chronically influence the results of OGTTs in the population. Gastro-duodenal surgery should be included among the factors which may significantly affect the chronic results and thereby also the clinical interpretation of the OGTTs in the population.

Blood Glucose↗
PubMed1979

Studies of the relationship between Schistosoma and their intermediate hosts. III. The genus Biomphalaria and Schistosoma mansoni from Egypt, Kenya, Sudan, Uganda, West Indies (St. Lucia) and Zaire (two different strains: Katanga and Kinshasa).

The compatibility between strains of Schistosoma mansoni from Egypt, Kenya, Sudan, Uganda, the West Indies, and Zaire (two strains which came from Katanga and from Kinshasa), and various species and strains of Biomphalaria, i.e. Biomphalaria pfeifferi, B. alexandrina, B. glabrata and B. camerunensis was investigated. Data as mortality, rate of infection of the surviving snails, duration of infection, cercarial production per day per positive snail, etc., were observed. The main emphasis was placed on determining the total cercarial production per 100 exposed snails for each snail population. It was possible to infect all the tested populations of B pfeifferi with the various strains of S. mansoni, but the observation as e.g. TCP/100 exposed snails varied greatly according to the population of snail and the strain of S. mansoni. The results for the remaining species of Biomphalaria varied greatly, depending on the combination, e.g. B. alexandrina was only susceptible to the local S. mansoni from Egypt. The highest TCP/100 exposed snails was more than 1 million for the strains of S. mansoni from Egypt, Kenya and the West Indies in B. alexandrina, B. pfeifferi and B. glabrata, respectively. The next group, with a TCP/100 exposed snails on 7--800 000 consists of S. mansoni from Sudan, Uganda and Zaire (Katanga) all in B. pfeifferi. The last tested strain of S. mansoni, Zaire (Kinshasa) yielded a cercarial production on 500 000 per 100 exposed snails in B. pfeifferi and B. camerunensis. The shortest prepatent period, 19 days, was observed for S. mansoni from Kinshasa, Zaire, in B. camerunensis, and the longest prepatent period, 25 days, was found for strains from Egypt and from the West Indies in B. alexandrina and B. glabrata, respectively. In general, a very long duration of infection, lasting up to 200 days, was observed.

Animals↗
PubMed1985

Multifactorial determination of skeletal age at death: a method and blind tests of its accuracy.

Traditional methods of estimating skeletal age at death have relied solely on the pubic symphyseal face or on this indicator combined with others in nonsystematic ways. A multifactorial method is presented that uses a principal components weighting of five indicators (public symphyseal face, auricular surface, radiographs of proximal femur, dental wear, and suture closure). This method has been tested by completely blind assessment of age in two samples from the Todd collection carefully screened for accuracy of stated age at death. Results show a marked superiority of the multifactorial method over any single indicator with respect to both bias and accuracy. This represents the first truly blind test of an age-at-death indicator or system, as the test populations were independent of the system(s) being tested, and the age, sex, and ethnogeographic origin of the individuals being assessed (as well as the compositions of the test samples with respect to these variables) were completely unknown until the tests were completed. Implications for paleodemography are discussed.

Adolescent↗
PubMed1987

Electrophysiology of supraoptico-paraventricular nucleus connections in the rat.

In an attempt to clarify the mechanisms involved during synchronous discharge of magnocellular neurosecretory cells of the supraoptic and paraventricular nuclei, extracellular action potentials were recorded from 149 single units located in the rat paraventricular nucleus. Responses of the cells to stimulation of the ipsilateral supraoptic nucleus were recorded and it was observed that 7% of paraventricular nucleus neurones could be antidromically identified as projecting to the supraoptic nucleus. Excitatory responses were recorded from 40% of cells tested and were probably mediated by an interneurone population. Inhibitory responses were recorded from 37% of the cells and may have been mediated by direct projections from the supraoptic nucleus. No differences in responses were recorded from cells identified as projecting to the median eminence or neurohypophysis as compared with the rest of the population tested. However, more of the phasically firing putative vasopressin-secreting cells, (58%) were excited than were continuously active cells (38%). Delivery of short trains of high-frequency stimulation induced bursts of discharge from 93% of cells so tested, regardless of response to single shock stimulation. These burst discharges showed a late onset as compared with responses following single shock stimulation. The results suggest that a complex of intra- and internuclear interactions serve to regulate the neurosecretory activity of magnocellular cells within the supraoptic and paraventricular nuclei.

Action Potentials↗
PubMed2000

Allergy and asthma in elite summer sport athletes.

Exercise may increase ventilation up to 200 L/min for short periods of time in speed and power athletes, and for longer periods in endurance athletes, such as long-distance runners and swimmers. Therefore highly trained athletes are repeatedly and strongly exposed to cold air during winter training and to many pollen allergens in spring and summer. Competitive swimmers inhale and microaspirate large amounts of air that floats above the water surface, which means exposure to chlorine derivatives from swimming pool disinfectants. In the summer Olympic Games, 4% to 15% of the athletes showed evidence of asthma or used antiasthmatic medication. Asthma is most commonly found in endurance events, such as cycling, swimming, or long-distance running. The risk of asthma is especially increased among competitive swimmers, of which 36% to 79% show bronchial hyperresponsiveness to methacholine or histamine. The risk of asthma is closely associated with atopy and its severity among athletes. A few studies have investigated occurrence of exercise-induced bronchospasm among highly trained athletes. The occurrences of exercise-induced bronchospasm vary from 3% to 35% and depend on testing environment, type of exercise used, and athlete population tested. Mild eosinophilic airway inflammation has been shown to affect elite swimmers and cross-country skiers. This eosinophilic inflammation correlates with clinical parameters (ie, exercise-induced bronchial symptoms and bronchial hyperresponsiveness). Athletes commonly use antiasthmatic medication to treat their exercise-induced bronchial symptoms. However, controlled studies on their long-term effects on bronchial hyperresponsiveness and airway inflammation in the athletes are lacking. Follow-up studies on asthma in athletes are also lacking. What will happen to bronchial hyperresponsiveness and airway inflammation after discontinuation of competitional career is unclear. In the future, follow-up studies on bronchial responsiveness and airway inflammation, as well as controlled studies on both short- and long-term effects of antiasthmatic drugs in the athletes are needed.

Asthma↗
PubMed2002

New advances in the biochemical diagnosis of pheochromocytoma: moving beyond catecholamines.

Pheochromocytomas are dangerous tumors that, although a rare cause of hypertension, require consideration among large numbers of patients. The resulting low prevalence of the tumor among tested populations and the inadequacies of commonly used biochemical tests make excluding or confirming the tumor an often difficult and time-consuming task. Recognition that catecholamines are metabolized to free metanephrines within pheochromocytoma tumor cells, and that this process is independent of catecholamine release, provides a rationale for use of these metabolites in the biochemical diagnosis of pheochromocytoma. Here we briefly review the history of biochemical diagnosis of pheochromocytoma in relation to recent data about the diagnostic utility of plasma free metanephrines for detection of these tumors. Measurements of urinary or plasma catecholamines have reasonable sensitivity for detection of most pheochromocytomas, particularly those in patients with sustained hypertension. False-negative test results can, however, occur in asymptomatic patients tested because of an adrenal incidentaloma or a familial predisposition for pheochromocytoma, or when sampling is carried out between episodes of paroxysmal hypertension. Measurements of urinary total metanephrines or vanillylmandelic acid are less reliable and are of little value as initial screening tests. In contrast, measurements of plasma concentrations or free metanephrines or 24-hour urinary outputs of fractionated normetanephrine and metanephrine almost always reveal the tumor. Although, both tests have similarly high sensitivity, the relatively low specificity of urinary fractionated metanephrines means that pheochromocytomas can be more efficiently excluded or confirmed using measurements of plasma free metanephrines.

Adrenal Gland Neoplasms↗
PubMed2000

Seroreactivity to Chlamydia trachomatis Hsp10 correlates with severity of human genital tract disease.

We have identified the chlamydial heat shock protein Hsp10 as a potential correlate to the immunopathogenic process in women with tubal factor infertility (TFI). The human serologic response to chlamydial Hsp10, Hsp60, and major outer membrane protein (MOMP) was measured by enzyme-linked immunosorbent assay. Three populations of women were studied: uninfected controls (CU), acutely infected (AI) women, and women with TFI. Sera from women in the AI and TFI groups both recognized Hsp10 more frequently and at a higher overall level than sera from healthy uninfected controls. Moreover, the infertile women had significantly greater Hsp10 seroreactivity than acutely infected women, indicating a concomitant increase of Hsp10 recognition in populations with increasing levels of disease severity. Hsp60 reactivity showed a similar correlation in these populations, while MOMP reactivity peaked at the same level in both AI and TFI populations but did not increase with disease severity. Test populations were standardized by level of reactivity to formalin-fixed Chlamydia trachomatis elementary bodies (EBs) to address whether these associations were reflections of increased overall chlamydial exposure rather than a property specific to Hsp10. Associations between Hsp10 seropositivity and TFI were greater in the EB(+) subgroup while associations among the EB(-) subgroup were diminished. When restricted to the EB(+) subgroups, Hsp60 and MOMP responses in the TFI population did not increase significantly over the level of AI group responses. Thus, among women with similar exposure to chlamydiae, the serologic response to Hsp10 exhibited a stronger correlation with TFI than did the response to Hsp60 or MOMP. These findings support the hypothesis that the serological response to C. trachomatis heat shock proteins is associated with the severity of disease and identifies Hsp10 as an antigen recognized by a significant proportion of women with TFI.

Acute Disease↗
PubMed1985

Eimeria tenella: relative survival of drug-resistant and drug-sensitive populations in floor pen chickens.

The effect was studied of introducing about equal numbers of decoquinate-sensitive or decoquinate-resistant Eimeria tenella oocysts into a floor pen of susceptible unmedicated chickens. "Sentinel" birds introduced 2, 3, 4, 5, and 6 weeks later were used to recover populations of E. tenella oocysts. In drug sensitivity tests, populations of oocysts harvested at 4 weeks were partially resistant to decoquinate medication. Oocysts obtained after 5 and 6 weeks were highly sensitive to decoquinate medication. The results indicate that drug-sensitive E. tenella parasites are more likely to dominate in absence of medication.

Animals↗
PubMed2003

False-positive tuberculin skin tests in a state prison system.

OBJECTIVE: To assess the existence and extent of false-positive tuberculin skin test (TST) results in a regularly tested population subsequent to switching to a different skin testing product. METHOD: Over 9300 state prison inmates were tuberculin skin tested as part of a routine annual testing program. A shortage of Tubersol caused the prison system to purchase and test with Aplisol. Prison health services staff reported an apparent increase in skin test positivity using Aplisol compared to Tubersol. Record reviews were conducted in 34 prisons where inmates read as positive (> or = 5 mm) were retested with Tubersol. RESULTS: Among 368 inmates recorded as positive (> or = 5 mm) with Aplisol who were retested with Tubersol, 150 (40.8%) were read as negative (0-4 mm). CONCLUSION: The tuberculin skin test is a valuable tool in evaluating patients for TB infection. However, variations in planting and reading the test, and in the consistency between lots and manufacturers, can contribute to errors in determining an individual's infection status. The entire clinical and epidemiological picture for each patient must always be evaluated using the TST as a tool, and not an indisputable answer.

False Positive Reactions↗
PubMed2005

Aniseikonia testing in an adult population using a new computerized test, "the Aniseikonia Inspector".

PURPOSE: To determine the measurement characteristics of a new computerized test, the Aniseikonia Inspector Version 1, on a sample of clinic patients. METHODS: Aniseikonia was measured in the vertical, horizontal, and oblique meridians on 320 patients (mean 55 years old, range 17-89 years) prior to their optometric exam using the psychometric methods programmed into the Aniseikonia Inspector Version 1. Statistical analyses were performed to determine the distribution of aniseikonia in the sample of patients and the relationships between the amount of aniseikonia and patients' habitual refractive correction, visual acuity, stereopsis and binocular alignment status. The characteristics of the individual measurements were also examined. RESULTS: The means and standard deviations of the measured aniseikonia in the vertical, horizontal, and oblique meridians were -0.5% (2.5%), -0.1% (3.3%) and 0.3% (2.8%) respectively. The means in the vertical and oblique meridians were significantly different from 0.0 (p=0.0001, p=0.0314) while that in the horizontal was not (p=0.61). The distributions of aniseikonia showed that 65.6%, 57.5% and 64.3% had within +/-1.0% aniseikonia in the vertical, horizontal and oblique meridians, respectively. Correspondingly, 16.9%, 25.6% and 25.8% had aniseikonia of +/-3.0% or greater. The discrepancy between these percentages and those expected in a normal distribution indicate that the distributions were significantly more peaked than a normal distribution. This departure from normal is due to a few extreme values in the tails. The magnitude of aniseikonia had no statistically significant relationship with the patients' habitual refractive correction, visual acuity or stereopsis. The effect of phoria on the amount of aniseikonia was significant, more so for measurements in the horizontal meridian. The individual measurements, which are the average of two trials using the method of adjustment, showed no significant bias, no relationship between the means and differences in the two readings, but large differences between the two readings. Measurements in the vertical direction seem to be more stable than those in the other two meridians. CONCLUSION: As measured with the Aniseikonia Inspector 1.0, the majority of the patients sampled in this study exhibited 1.0% or less aniseikonia and were therefore not likely to have symptoms related to aniseikonia. At least 17% of patients had 3.0% or greater aniseikonia measured in the vertical meridian. The Aniseikonia Inspector warrants further evaluation in a clinical setting because of the large limits of agreement between the two settings that are average to determine the magnitude of the aniseikonia. These limits differ considerably from those established by the designers and, therefore, raise questions regarding the actual resolution of the instrument as compared to the nominal resolution.

Adolescent↗
PubMed1987

Exercise test variables of a population with maximal bicycle exercise test.

The aim of the study was to establish reference values for appraising the circulatory response of men and women to age-predicted maximal heart rate (220-age) exercise testing. The data of exercise testing have been analysed in 942 subjects (608 men and 334 women). Under exercise testing the mean maximal heart rate was 177/min in both sexes. Increase in heart rate per minute of exercise was 5.59 +/- 1.93 in men, 9.00 +/- 4.94 in women. At the peak of exercise test, systolic blood pressure was considerably higher in men than in women (188.96 +/- 27.98 vs. 171.66 +/- 28.46 mmHg; p much less than 0.0001). The average working capacity was 1.7 W/kg among men and 1.31 W/kg among women. The duration of exercise testing time was significantly longer in men than in women (918.6 + 269.4 vs. 578.4 +/- 193.2 s; p less than 0.0001). Reference values for testing time are given according to sex and age with due consideration of body weight and height.

Adult↗
PubMed2001

Comparative sensitivity of three populations of the cladoceran Moinodaphnia macleayi to acute and chronic uranium exposure.

Assessment of differences in the response of three different populations of the tropical cladoceran Moinodaphnia macleayi to uranium exposure was evaluated. The populations tested included a laboratory stock (maintained for 10 years), a wild population collected from Bowerbird Billabong (an uncontaminated environment), and a population collected from Djalkmara Billabong (a relatively contaminated environment with elevated levels of uranium), located on the Ranger uranium mine site, Jabiru East, NT, Australia. Chronic and acute toxicity of uranium was determined for all three populations. The no-observed-effect-concentration (NOEC; reproduction) and lowest observed-effect-concentration (LOEC; reproduction) for uranium ranged between 8-31 micrograms L-1 and 20-49 micrograms L-1, respectively, for all three populations. The 48 h EC50 (immobilization-lethality) for uranium ranged between 160-390 micrograms L-1 for all three populations. There was little difference in the response of the three populations of M. macleayi to acute and chronic uranium exposure, although the response of the laboratory population to chronic uranium exposure appeared more variable than the "wild" populations. There was no apparent tolerance in the population of M. macleayi obtained from Djalkmara Billabong when exposed to elevated levels of uranium. M. macleayi was significantly more sensitive to uranium exposure than other species previously tested. It was concluded that the sensitivity of the laboratory population (to uranium) is still representative of natural M. macleayi populations.

Animals↗
PubMed1986

Multicenter clinical trial and laboratory utilization of an enzymatic detection method for gonococcal antigens.

Seven institutions participated in a comparative study evaluating standard culture method and a new enzyme immunoassay (EIA, Gonozyme, Abbott Diagnostics) for the detection of Neisseria gonorrhoeae. Five hundred twenty-three patients were entered from hospitals of various sizes representing different population densities, ethnic and economic sectors, and gonococcal prevalence. Statistical analysis showed sensitivity, specificity, and positive and negative predictive values of 80.3%, 94.6%, 66.2%, and 97.3% for the total population tested. For the high-prevalence (greater than 15%) population the respective values were as follows: 78.6%, 91.5%, 68.8%, and 94.7%. Specimens from females had a lower sensitivity than those from males. In the low-prevalence population (less than 10%) results were as follows: 100%, 97.8%, 50%, and 100%. A cost comparison emphasized the benefit of the Gram's stain and culture. It also indicated that, unless batched or assayed at high volume, Gonozyme is not cost competitive for laboratories using standard culture methods. The impact of the EIA method, in general, and Gonozyme, specifically, on the microbiology section also was investigated. Integration would require altering of established work patterns and loss of flexibility and freedom of standard plating technics. The fact that Gonozyme is a "presumptive" test limits it to being a complementary assay, not an alternative. The authors conclude that Gonozyme is optimally suited to a high-volume laboratory, screening a low-prevalence female outpatient population, where specimen transport is a problem and gonococcal resistance to penicillin has not been demonstrated. This would include sexually transmitted disease clinics, reference laboratories, and state health departments.

Antigens, Bacterial↗
PubMed2003

Large-scale search of SNPs for type 2 DM susceptibility genes in a Japanese population.

The etiology of type 2 diabetes (DM) is polygenic. We investigated here genes and polymorphisms that associate with DM in the Japanese population. Single-nucleotide polymorphisms (SNPs) of 398 derived from 120 candidate genes were examined for association with DM in a population-based case-control study. The study group consisted of 148 cases and 227 controls recruited from Funagata, Japan. No evident subpopulation structure was detected for the tested population. The association tests were conducted with standard allele positivity tables (chi(2) tests) between SNP genotype frequency and case-control status. The independent association of the SNPs from serum triglyceride levels and body mass index was examined by multiple logistic regression analysis. A value of P<0.01 was accepted as statistically significant. Six genes (met proto-oncogene, ATP-binding cassette transporter A1, fatty acid binding protein 2, LDL receptor defect C complementing, aldolase B, and sulfonylurea receptor) were shown to be associated with DM.

ATP-Binding Cassette Transporters↗
PubMed1998

Onset of resistance to fenvalerate, a pyrethroid insecticide in Argentine horn flies (Diptera: Muscidae).

Haematobia irritans (L.) horn flies recently have immigrated into Argentina from Brazil or Paraguay. Bioassays were conducted with fenvalerate to develop baseline information on pyrethroid susceptibility. Four populations tested in 1994 and 1995 were more susceptible than a laboratory strain of horn fly not exposed to insecticides since 1970, but 3 populations from Corrientes Province tested in 1996 were moderately resistant to fenvalerate, with resistance ratios ranging from 3 to 26. Argentine horn fly populations were exposed to pyrethroid treatments of pour-on, spray, and dip formulations for 4 yr before developing resistance. Horn flies in the United States developed pyrethroid resistance after 2 yr of treatment with pyrethroid ear tags.

Animals↗
PubMed1994

Impairment of feedforward inhibition in CA1 region of hippocampus after chronic benzodiazepine treatment.

The strength of feedforward inhibition was assessed in the CA1 region of in vitro hippocampus of benzodiazepine tolerant rats 2 and 7 days after 1 week oral flurazepam (FZP) administration. Feedforward inhibition was activated with a Schaffer collateral stimulation just-subthreshold for a population spike followed at intervals of 10-100 ms by test population spikes elicited from the subicular side of the recording electrode. The amplitude of test spike was reduced to a lesser degree 2 days, but not 7 days, after FZP treatment, suggesting a decrease feedforward inhibition in treated rats coinciding with the time course for reversal of anticonvulsant tolerance in vivo.

Animals↗
PubMedDate not supplied

[Analysis of mutations in the CFTR gene in patients diagnosed with cystic fibrosis in Poland].

Polish CF patients were screened extensively for mutations in the CFTR gene. Screening data demonstrated a high heterogeneity of CFTR mutations in the Polish population. Total 30 different mutations were characterised in 24 exons or introns of the gene. Among them, six mutations have been reported for the first time and submitted to the CF Genetic Analysis Consortium. In addition, 15 different polymorphisms were found, including three new ones. The screening resulted in 9% increase of the detection rate of CFTR alleles in the tested population. Frequencies of two of the identified mutations (CFTRdele2,3 and 2184insA) are relatively high (2.6% and 1%, respectively) and justify their inclusion into routinely screened mutations in genetic testing of Polish CF population.

Cystic Fibrosis↗