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Urinary 5 alpha-androstanediol and 5 beta-androstanediol measurement by gas chromatography after solid-phase extraction and high-performance liquid chromatography.

Urinary androstanediol measurement, often in association with other androgens, is commonly used to support the clinical diagnosis of idiopathic hirsutism. In addition, androgen excess has been shown to be the endocrine abnormality which characterizes patients with breast cancer. We recently developed a method for the measurement of urinary testosterone employing solid-phase extraction and HPLC purification before quantitative measurement by gas chromatography. In the present report we verify the feasibility of the method for the simultaneous measurement of 5 alpha-androstane-3 alpha,17 beta-diol and 5 beta-androstane-3 alpha,17 beta-diol in addition to testosterone in the same urine sample. The mean recovery for the whole procedure was 89.8% for 5 alpha-androstane-3 alpha,17 beta-diol and 87.8% for 5 beta-androstane-3 alpha, 17 beta-diol. The estimates of the coefficients of variation were 4.9% (95% confidence limits: 3.9-6.5%) and 3.9% (95% confidence limits: 3.1-5.2%), respectively. Accuracy was evaluated by standard addition and dilution assays and a linear relationship was found between expected and observed values (r2 = 0.997 for 5 alpha-androstane-3 alpha,17 beta-diol and r2 = 0.999 for 5 beta-androstane-3 alpha,17 beta-diol). The method is rapid, effective and suitable for the measurement of testosterone, 5 alpha-androstanediol and 5 beta-androstanediol in the same urine sample.

Androstane-3,17-diol↗
PubMed1992

Lack of interaction between propofol and vecuronium.

We estimated the potency of vecuronium and measured the onset and duration of its action during total intravenous anesthesia with propofol to examine the possibility of any interaction between these two drugs. Propofol infusion was administered according to a three-step dosage scheme, and neuromuscular block was monitored by measuring the force of contraction of the adductor pollicis muscle after single-twitch stimulation of the ulnar nerve at 0.1 Hz. A control group of patients were similarly studied during anesthesia with thiopental, nitrous oxide, oxygen, and fentanyl. The ED50 and ED95 (dose required to produce a 50% and 95% depression of twitch tension, respectively) of vecuronium in patients given total intravenous anesthesia (n = 24) were 24 (22-27, 95% confidence limits) and 41 (37-48, 95% confidence limits) micrograms/kg, respectively, and in the control group (n = 24), 20 (17-24) and 39 (34-37) micrograms/kg, respectively. The onset of action of an 80-micrograms/kg dose (2 x ED95) of vecuronium was 3.6 +/- 1.2 and 4.1 +/- 1.7 min (mean +/- SD), in the propofol (n = 10) and control (n = 10) groups, respectively. The respective times to recovery of the twitch height to 25% of control and the recovery indices (25%-75% recovery of twitch height) in the propofol versus control groups were 28.3 +/- 6.6 and 28.0 +/- 1.7 min and 13.3 +/- 6.8 and 15.4 +/- 11.9 min, respectively. There were no significant differences in any of the measured variables between the propofol and control groups, indicating the lack of any interaction between propofol and vecuronium.

Adult↗
PubMed1986

Some clinical aspects of uroflowmetry in elderly males. A population survey.

A random sample of 200 males aged 50 years or more was selected from the National Register in order to investigate various aspects of spontaneous uroflowmetry and to estimate the frequency of prostatism and symptoms of lower urinary tract dysfunction. All in all the data from 112 persons were analysed. The prevalence of prostatism was found to be 17% (95% confidence limits 11-26%), while 88% (95% confidence limits 83-95%) experienced various degrees of symptoms. Only few associations between single symptoms and uroflowmetry variables were demonstrated. However, statistically significant correlations were revealed between obstructive and total symptom scores on one hand and maximum and average flow rates on the other hand. As the correlations were modest and a considerable overlap of uroflow variables in persons with and without prostatism were proved, the diagnostic specificity and sensitivity of maximum flow rate as well as other uroflow variables were low in the screening for prostatism. In conclusion uroflowmetry appears inefficient to confirm a clinical impression of prostatism.

Aged↗
PubMed1989

Prediction of survival during induction therapy in patients with newly diagnosed acute myeloblastic leukemia.

Among 569 patients with newly diagnosed AML, 16% died in the 4 weeks following initiation of remission induction therapy. Eight pretreatment characteristics were found to be independently associated with 4-week survival: performance status, bilirubin, age, neutrophil count, fibrinogen, albumin, hemoglobin, and creatinine. A model incorporating these characteristics prospectively stratified a separate group of 198 patients into two comparably sized groups differing substantially in both 4-week survival rates (71% (95% confidence limits, 61-80%) vs. 91% (95% confidence limits, 83-96%] and in survival rates throughout remission induction. Characteristics associated with failure to survive 4 weeks were unassociated with resistance to therapy. This suggests that patients who fail to survive induction are qualitatively different than patients who survive induction but exhibit resistance to treatment. Different therapeutic strategies might be appropriate in the two groups. The model presented here can be used to identify patients at increased risk of death during remission induction.

Adult↗
PubMed1993

Interferon-alpha 2a does not improve response or survival when combined with dacarbazine in metastatic malignant melanoma: results of a multi-institutional Australian randomized trial.

Following extensive phase II trials of the combination of dacarbazine and interferon-alpha 2a we performed a prospective, randomized, controlled trial of this combination versus dacarbazine alone as systemic therapy for symptomatic, measurable metastatic malignant melanoma. The two treatment arms were well matched for age, sex, performance, status, relapse-free survival, prior therapy and sites of disease. Therapy consisted of dacarbazine given in combination in escalating doses of 200 mg/m2, 400 mg/m2 and 800 mg/m2 i.v. every 3 weeks, or alone at 800 mg/m2 i.v. every 3 weeks. Interferon was administered subcutaneously starting at 3 mU daily on days 1-3, 9 mU daily on days 4-70, then 9 mU three times per week. Therapy was continued for at least 6 months unless overt progressive disease was observed. Eighty seven patients were randomized to the combination and 83 patients to dacarbazine alone. Response rates were respectively, complete 7% and 2%, and partial 14% and 15%, for a total response rate of 21% (95% confidence limits 13-31%) and 17% (95% confidence limits 10-27%). Median duration of response was 258 and 286 days, and survival of the whole groups 229 and 269 days respectively. Toxicity was worse in the combination arm, with more patients experiencing fatigue, nausea and anorexia, flu-like symptoms and neutropenia. However quality of life was not significantly different in either group, except that fatigue, as measured at week 12 by LASA scales, and activity, as measured by the functional living index, were both improved in the combination.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1977

Correlates of maximal oxygen consumption during treadmill exercise.

According to the Balke treadmill protocol, 39 healthy male USAF volunteers were subjected to maximal exercise. The subjects as a group passed the anaerobic threshold by the end of exercise since average venous lactate concentrations increased from 11.2 +/- 1.6 mg% (95% confidence limits) to 93.0 +/- 8.5 mg% (95% confidence limits), and the average gas exchange ratio (R) at the end of the exercise was greater than unity (p less than 0.0005). Tests for correlations showed weak but statistically significant (p less than 0.05) relationships between change in venous lactic acid concentrations and R (r = 0.44) and maximal heart rate (r = 0.34). Maximal oxygen consumption was correlated with time of exercise (r = 0.70) and subject weight (r = 0.33). Subject age and initial plasma lactate concentrations were not significantly correlated with any other variables. Multiple linear regression yielded an equation for prediction of maximal oxygen consumption which included terms for time of exercise and subject weight. Although the multiple correlation coefficent (r = 0.75) was statistically significant (p less than 0.05), it was considered insufficient for accurate prediction of maximal oxygen consumption.

Adult↗
PubMed1987

Nerve cell atrophy and loss in the inferior olivary complex of "Purkinje cell degeneration" mutant mice.

The genetically determined loss of cerebellar Purkinje cells (PCs) in "Purkinje cell degeneration" (pcd) mutant mice deprives inferior olivary (IO) neurons of their major postsynaptic target. The degeneration of PCs starts on postnatal day (P) 17 and loss of these neurons is virtually complete by P45. We examined the inferior olivary complex (IOC) of normal and pcd mutant mice by quantitative light microscopy to determine whether the degeneration of PCs is associated with atrophy and loss of their presynaptic neurons in the IOC. The number of IO neurons in 17-day-old mutants did not differ significantly from controls (P greater than .1). IO neurons in 23-day-old mutants were 23% (95% confidence limits: 12-34%) fewer than in age-matched controls, and in 300-day-old mutants they were 48% (95% confidence limits: 37-58%) fewer than in their controls (P less than .001 in both cases). The decline of the number of IO neurons in pcd mice between days 17 and 300 was 49% (P less than .0001; 95% confidence limits: 38-57%). The medial accessory olive (MAO) appeared less affected than the principal (PO) and the dorsal accessory olive (DAO). The mean neuronal diameter in control mice was 11.6 micron at 23 days and 10.8 micron at 300 days of age. The respective values in pcd mutants were 11.5 micron and 8.7 micron. Diameters in old mutants were significantly smaller than those in both age-matched controls and young mutants (P less than .001). These findings suggest that in the mature olivocerebellar system the stability of IO neurons depends on the state of their postsynaptic PCs.

Animals↗
PubMed1975

Normal hemoglobin-oxygen affinity.

Hemoglobin-xoygen affinity is known to vary in a number of disease states. The authors measured the continuous affinity of blood from healthy subjects and, using mathematical data reduction techniques, calculated coefficients for rational function models of average normal affinity, plus or minus 2 standard deviations, and 95 per cent confidence limits. Average normal P50 was 27.10 torr, with a two-standard-deviation range of 25.85 to 28.35; P50s of the 95 per cent confidence limits were 26.69 and 27.53 torr. The affinity usually accepted as standard lay between or very near to the 95% confidence limits of normal throughout its range. It is concluded that the range of normal affinity is narrow and that, for most practical purposes, standard affinity adequately represents normal affinity. There should be little difficulty in distinguishing from normal the shifts that occur in certain disease conditions.

Acid-Base Equilibrium↗
PubMed2000

A phase III trial of ifosfamide with or without cisplatin in carcinosarcoma of the uterus: A Gynecologic Oncology Group Study.

OBJECTIVE: The aims of this study were to substantiate the previously reported activity of ifosfamide in patients with advanced, persistent, or recurrent carcinosarcoma (mixed mesodermal sarcoma) of the uterus, and to determine whether the addition of cisplatin results in an improved response or survival. Secondarily, we sought to determine the toxicity of ifosfamide-cisplatin in this patient population. METHODS: Patients were randomized to receive ifosfamide (1.5 g/m(2)/day) times 5 days every 3 weeks for eight courses with mesna uroprotection, with or without cisplatin (20 mg/m(2)/day) times 5 days. No patient had received previous chemotherapy. RESULTS: Of 224 patients entered on this study, 30 were ineligible for a variety of reasons, leaving 194 evaluable patients. Early in the study, the dose of the combination regimen was reduced by 20% (1 day) because of toxicity. The investigational arms were balanced for age, grade, and Gynecologic Oncology Group performance status. Percentages of adverse effects reported in 191 patients receiving chemotherapy included (ifosfamide/cisplatin-ifosfamide) grade 3 or 4 granulocytopenia (36/60), grade 3 or 4 anemia (8/17), grade 3 or 4 central nervous system toxicity (19/14), and grade 3 or 4 peripheral neuropathy (1/12). Treatment may have contributed to the deaths of 6 patients treated with full doses of ifosfamide and cisplatin for 5 days. The proportion of patients responding to ifosfamide alone versus ifosfamide-cisplatin therapy was (0.36 versus 0.54) overall, 0.47 versus 0.61 for pelvic, 0.21 versus 0.54 for lung, and 0.33 versus 0.40 for "other" metastatic sites of measurable disease. The relative odds ratio of response adjusted for measurable sites of disease was 1.82 (P = 0.03, one-tailed test; 95% lower confidence limit, 1.06). Progression-free survival (PFS) and survival data suggest that the combination offers a slight prolongation of PFS (relative risk, 0.73; 95% upper confidence limit, 0.94; P = 0.02, one-tailed test), but no significant survival benefit (relative risk, 0.80, 95% upper confidence limit, 1.03; P = 0.071, one-tailed test). CONCLUSION: The addition of cisplatin to ifosfamide appears to offer a small improvement in progression-free survival over ifosfamide alone in the management of advanced carcinosarcoma of the uterus; the added toxicity may not justify the use of this combination.

Adult↗
PubMed1986

A population-based case-control study of mesothelioma deaths among U.S. railroad workers.

We have completed a case-control analysis of mesothelioma deaths among current and retired U.S. railroad employees. Cause-specific death certificates were obtained for 87% of 15,059 deaths reported by the railroad retirement board, and 20 mesotheliomas were identified according to death certificate diagnosis. A 10:1 matched analysis with railroad workers dying of nonmalignant, nonaccidental causes yielded a very strong association with prior railroad work in jobs with potential asbestos exposure (odds ratio = 7.2, 95% lower confidence limit = 3.3). Consideration of railroad occupations with regular asbestos exposures (e.g., skilled trades, steam locomotive repair) yielded an odds ratio of 21.4 (95% lower confidence limit = 8.7), but the occupations with potential intermittent exposure (e.g., engineers, firemen, carmen) yielded a nonsignificant odds ratio of 2.3 (95% lower confidence limit = 0.5). Applying mesothelioma mortality rates from this study to the population of U.S. railroad workers at risk yields an estimate of 416 cases of mesothelioma occurring among U.S. railroad workers between 1981 and 2000.

Adult↗
PubMed1985

Scaling segmental moments of inertia for individual subjects.

The purpose of this investigation was to validate methods of scaling human segmental moments of inertia for the transverse principal axis. Firstly, two methods of scaling Chandler et al.'s (Pamphlets DOT HS-801 430 and AMRL TR-74-137, Wright Patterson Air Force Base, OH, 1975) mean subject data to estimate the segmental moments of inertia were used. Chandler et al.'s data were scaled using body mass and segment length (formula 1) or body mass and standing height (formula 2). These data were then compared with a procedure of using the cadaver whose anthropometric measurements most closely match those of the subject. The difference between the criterion data (Chandler's subject data) and scaled values were plotted on scatter diagrams with confidence limits of p less than 0.05 at d.f. = 17. For procedure 1, 43% of the scaled values were plotted within the confidence limits using formula (2) (mass and standing height), compared with 26% for formula (1) (mass and segment length). Formula (1) markedly underestimated the tallest and heaviest subjects. In procedure 2, only 16% and 21% of the scaled values, using formula (1) and (2), respectively, fell within the confidence limits. Results suggested that scaling formulae approximate the moment of inertia of body segments with only limited accuracy. However, if scaling was to be adopted then mean moment of inertia data from an appropriate data set, using the formula that incorporates subject mass and standing height, gave results closest to the criterion value.

Anthropometry↗
PubMed2003

Anthelmintic treatment in horses: the extra-label use of products and the danger of under-dosing.

Anthelmintic products form the basis of helminth control practices on horse stud farms at present. Regular evaluation of the efficacy of these products is advisable, as it will provide information on the worm egg reappearance period and the resistance status in the worm population. The aim of this study was to evaluate the efficacy of doramectin, pyrantel pamoate, ivermectin and moxidectin on a Thoroughbred stud farm in the Western Cape Province, South Africa. The study also compared the anthelmintic efficacy of two moxidectin formulations administered at their recommended dosages (an injectable, at 0.2 mg/kg, not registered for horses, and an oral gel at 0.4 mg/kg, registered for horses). Two mixed-sex groups of 30 yearlings and 40 weaners were tested in 2001 and 2002, respectively, divided into 3 and 4 groups of equal size. In 2001, moxidectin was one of 3 drugs administered orally and at a dose rate of 0.4 mg/kg. In 2002, pyrantel pamoate and ivermectin were orally administered at 19 and 0.2 mg/kg. Moxidectin and doramectin (the latter not registered for horses) were administered by intramuscular injection at a dose of 0.2 mg/kg, the dosage registered for other host species. The faecal egg count reduction test was used to determine the anthelmintic efficacies in both years. Each animal acted as its own control and the arithmetic mean faecal egg count and lower 95% confidence limit was calculated for each of the groups. A 100% reduction in the faecal egg counts and a 100% lower 95% confidence limit was recorded for moxidectin (0.4 mg/kg) in 2001. In 2002, a 99% and 96% reduction was recorded for pyrantel pamoate and ivermectin, respectively. In the same year doramectin and moxidectin (both injectable and given at 0.2 mg/kg) did not have any effect on worm egg counts. Of the 4 drugs tested in 2002, only pyrantel pamoate recorded lower 95% confidence limits above 90%.

Administration, Oral↗
PubMed1986

Urodynamic investigation predicts bladder dysfunction at an early stage after abdominoperineal resection of the rectum for cancer.

In a prospective study, 25 consecutive patients (14 men and 11 women) who underwent abdominoperineal resection of the rectum were urodynamically investigated before surgery and 10 days, one month, and three months after the operation. Nine men and three women (48% and 95% confidence limits; range 28% to 69%) developed voiding disturbances 10 days after the operation. One man and one woman developed incomplete lower motor neuron lesion (8% and 95% confidence limits; range 1% to 26%). At follow-up 3 months after surgery, five patients (20% and 95% confidence limits; range 7% to 41%) had still voiding disturbances: two patients with lower motor neuron lesion and three men with bladder outlet obstruction caused by prostatic hypertrophy. The three men underwent transurethral resection of the prostate 6 months after excision of the rectum. It is concluded that the risk of neurogenic bladder and voiding dysfunction is a minor problem. Cystometry performed before removal of the vesical catheter around the tenth postoperative day will diagnose patients with neurogenic bladder dysfunction. If voiding symptoms persist beyond 3 months after the operation, further urodynamic investigations should be undertaken to find patients with bladder dysfunction not due to lesion of the peripheral parasympathetic nerves to the bladder, which could demand surgery.

Abdomen↗
PubMed2000

SMR analysis of historical follow-up studies with missing death certificates.

The evaluation of epidemiological follow-up studies is frequently based on a comparison of the number O of deaths observed in the cohort from a specified cause with the expected number E calculated from person years in the cohort and mortality rates from a reference population. The ratio SMR = 100 x O/E is called the standardized mortality ratio (SMR). While person years can easily be calculated from the cohort and reference rates are generally available from the national statistical offices or the World Health Organization (WHO), problems can arise with the accessibility of the causes of death of the deceased study participants. However, the information that a person has died may be available, e.g., from population registers. In this paper, a statistical model for this situation is developed to derive a maximum likelihood (ML) estimator for the true (but unknown) number O* of deaths from a specified cause, which uses the known number O of deaths from this cause and the proportion p of all known causes of death among all decreased participants. It is shown that the standardized mortality ratio SMR* based on this estimated number is just SMR* = SMR/p. Easily computable confidence limits can be obtained by dividing the usual confidence limits of the SMR by the opposite limit of the proportion p. However, the confidence level alpha has to be adjusted appropriately.

Biometry↗
PubMed1988

Solid cancer risk after treatment of Hodgkin's disease.

We pooled the data from seven studies of second cancer risk after treatment of Hodgkin's disease (HD) and estimated the relative risks (RR) of solid cancers (SC) for the following two treatment groups: (1) radiotherapy, with or without chemotherapy; and (2) chemotherapy alone. For all treatment groups combined, the RR of SC was 2.1 (95% confidence limits: 1.8 to 2.4). In the radiotherapy group, statistically significant RR were found for SC for all anatomic sites (RR: 2.2; 95% confidence limits: 1.9 to 2.6) and for SC of the bones and joints (RR: 20.0), soft tissues (RR: 18.3), non-HD lymphomas (RR: 8.1), melanomas of the skin (RR: 6.7), buccal cavity and pharynx (RR: 4.1), nervous system (RR: 3.6), respiratory system (RR: 2.5), and digestive system (RR: 1.8). In the chemotherapy alone group, none of the RR differed significantly from unity, and the RR for SC of all sites was 1.1 (95% confidence limits: 0.5 to 1.9). The average duration of follow-up for patients with chemotherapy was shorter than the duration of follow-up for patients with radiotherapy. This may explain the general absence of elevated RR after chemotherapy.

Drug-Related Side Effects and Adverse Reactions↗
PubMed1990

Evaluation of heartworm immunodiagnostic tests.

In this report, the use of appropriate statistical methods for the evaluation of heartworm immunodiagnostic tests is discussed. The evaluation of these tests is complicated by factors causing variation in sensitivity, specificity, accuracy, and predictive values of positive and negative test results. The primary sources of inconsistency are variation in the prevalence of heartworm infection among populations of dogs and the sensitivity of immunodiagnostic tests to various categories of heartworm infections (ie, patent, immune-mediated occult, unisex occult, and immature occult). Sample size (ie, number of dogs tested) affects the confidence limit values of sensitivity and specificity. At least 100 dogs should be used in each testing group (infected and uninfected) to generate values of sensitivity or specificity within reasonably narrow confidence limits. Use of more than 200 dogs in each testing group contributes little to further narrowing of confidence limits. The selection of appropriate statistical tests for comparison of tests or comparison of the sensitivity or specificity of a single diagnostic test to various categories of heartworm infections is critical. The McNemar paired chi 2 test is appropriate for comparison of diagnostic tests, but it must be done by use of duplicate sera from each animal. A chi 2 test of independence, or, in the case of a small sample size, the Fisher exact test, is appropriate for comparing the sensitivity or specificity of a single diagnostic test to various categories of heartworm infection.

Animals↗
PubMed1979

Risk of cutaneous carcinoma in patients treated with oral methoxsalen photochemotherapy for psoriasis.

A 2.1-year prospective study of 1373 patients given oral 8-methoxypsoralen photochemotherapy for psoriasis revealed 30 patients with a total of 48 basal-cell and squamous-cell carcinomas. The observed incidence of cutaneous carcinoma was 2.63 (95 per cent confidence limits = 1.91 to 3.90) times that expected for an age, sex and geographically matched population. Relative risk to patients with history of ionizing radiation was 3.68 (99 per cent confidence limits, 2.42 to 8.69). Patients with a previous cutaneous carcinoma had a relative risk of 10.22 (99 per cent confidence limits, 4.78 to 37.08). A higher than expected proportion of squamous-cell carcinomas and an excess of squamous-cell carcinomas in areas not exposed to sun were seen. New patients with known histories of ionizing-radiation exposure or of skin tumors should be given 8-methyoxypsoralen photochemotherapy only if they understand the risks and have disabling psoriasis untreatable by other means.

Administration, Oral↗
PubMed1994

Relative potency of vecuronium in male and female patients in Britain and Australia.

We compared the potency of vecuronium when given to similar patients in Brisbane, Australia, and Cardiff, United Kingdom. Forty patients in each centre were anaesthetized using the same technique with propofol, fentanyl, nitrous oxide and vecuronium either 20 or 30 micrograms kg-1 by random allocation. Neuromuscular block was measured with similar Datex Relaxographs. There was no significant difference in potency between British and Australian patients. The ED50 and ED95 for a British male of average weight were 29.5 micrograms kg-1 (95% confidence limits 27.3-32.3 micrograms kg-1) and 51.3 micrograms kg-1 (44.3-63.9 micrograms kg-1), respectively. ED50 and ED95 for Australians were 5.5% greater, with confidence limits from 4% less to 17% greater. Females were significantly more sensitive to vecuronium than males, requiring 22% less drug to achieve the same degree of neuromuscular block (confidence limits 12-32%). The results are consistent with the ED50 being independent of body weight when the dose is expressed as microgram kg-2/3, but not as microgram or microgram kg-1.

Adolescent↗