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PubMed1990

Estrogen replacement therapy and the risk of endometrial cancer: remaining controversies.

To examine the relationship between exogenous estrogen administration and endometrial cancer, we used data from the Cancer and Steroid Hormone Study, a multicenter, population-based case-control study. Estrogen replacement therapy for greater than or equal to 2 years was associated with an increased risk of both localized and extrauterine cancer (relative risk = 2.8, 95% confidence limits 1.6, 4.6; relative risk = 2.9, 95% confidence limits 0.9, 9.4, respectively). However, the latter finding was based on a small number of cases in which estrogen was used. Women who underwent estrogen replacement therapy for greater than or equal to 2 years had significantly elevated risks of endometrial cancer (2.1 for 2 to 5 years and 3.5 for greater than or equal to 6 years). An elevated risk persisted for greater than or equal to 6 years after discontinuation of therapy. Women who exclusively used conjugated equine estrogen preparations less than or equal to 0.625 mg had no increased risk of endometrial cancer. A history of oral contraceptive use appeared to reduce the risk of endometrial cancer associated with estrogen replacement therapy. However, these latter two potentially important findings were based on a small number of cases in which hormones were used.

Adult↗
PubMed1988

Comparison of delayed-release 5-aminosalicylic acid (mesalazine) and sulfasalazine as maintenance treatment for patients with ulcerative colitis.

To assess the safety and efficacy of delayed-release mesalazine (5-aminosalicylic acid) as maintenance treatment for patients with ulcerative colitis, 100 patients with quiescent colitis were randomly grouped to receive either delayed-release mesalazine or an equivalent dose of enteric-coated sulfasalazine in a 48-wk trial. Groups were comparable for age, sex, and duration and extent of disease. Relapse rates at 48 wk were as follows: sulfasalazine 38.6% (95% confidence limits, 24%-54%) and mesalazine 37.5% (95% confidence limits, 24%-53%), chi 2 = 0.01, p greater than 0.90. Mean time to relapse, cumulative relapse rate, and relapse severity were similar in the two groups. Headaches and upper gastrointestinal symptoms--common at trial entry--improved to a greater extent in patients receiving mesalazine. Delayed-release mesalazine is an effective treatment for maintaining ulcerative colitis remission and is associated with fewer side effects than equivalent doses of enteric-coated sulfasalazine.

Adult↗
PubMed1995

Ultrasound therapy in musculoskeletal disorders: a meta-analysis.

We have reviewed 293 papers published since 1950 to assess the evidence of effect of ultrasound in the treatment of musculoskeletal disorders. Twenty-two clinical papers describing trials comparing ultrasound treatment with sham-ultrasound treated, non-ultrasound treatment and untreated groups were found. These papers were evaluated with respect to a list of criteria which should be met in this type of trial. They were generally found lacking with respect to description of drop-outs, randomisation methods, ultrasound apparatus, sham-ultrasound apparatus, control of apparatus, mode of delivery, size of sound-head, treated area and follow-up time. In 16 of these trials, ultrasound treatments were compared with sham-ultrasound and in 13 cases data were presented in a way that made pooling possible. Two standardized effect sizes (dd/r and dd/s) were applied to the results to enable evaluation of the effect of ultrasound treatment on pain. None of the methods (dd/r = 0.64%, confidence limits -6.7 to 7.5%; and dd/s = 0.24, confidence limits -0.01 to 0.49) gave evidence that pain relief could be achieved by ultrasound treatment. Hence we found no reason to analyze the other papers where ultrasound treatment was compared with another treatment or an untreated control group. We found a significant influence of degree of blinding using the d/s for the analysis (t test, P = 0.009), while when the d/r was used, only a trend was found (P = 0.10). An analysis of the effect of proper randomisation on the result was not possible because of inadequate description of the methods used. We conclude that the use of ultrasound in treatment of musculoskeletal disorders is based on empirical experience, but is lacking firm evidence from well-designed controlled studies. One question remaining is whether ultrasound treatment can augment an effect of exercise therapy with respect to musculoskeletal disorders.

Clinical Trials as Topic↗
PubMed1990

Low sodium intake corrects abnormality in beta-receptor-mediated arterial vasodilation in patients with hypertension: correlation with beta-receptor function in vitro.

To determine the contribution of altered beta-receptor function in the vasculature to the increased peripheral vascular resistance seen in hypertension, the effects of intra-arterial infusions of isoproterenol and epinephrine on forearm blood flow were determined in 11 male normotensive subjects and 11 male hypertensive subjects during 10 and 250 mmol/day sodium diets. Increased sodium intake from 10 to 250 mmol produced contrasting effects in the hypertensive and normotensive subjects. In the hypertensive subjects, sensitivity to isoproterenol decreased when sodium intake increased (median effective dose increased from 39 [95% confidence limits, 30 to 50] to 70 [95% confidence limits, 42 to 116] ng/min, p less than 0.05). On the other hand, in the normotensive subjects increased sodium intake resulted in an increased sensitivity to isoproterenol induced vasodilation (median effective dose decreased from 52 [38 to 71] to 29 [22 to 38] ng/min, p less than 0.01). No change occurred in sensitivity to epinephrine or in the maximum vasodilatory response to ischemia during dietary changes. Changes in beta-receptors on lymphocyte membranes paralleled the changes seen in vascular sensitivity so that the proportion of receptors exhibiting high affinity for agonists, a reflection of receptor adenylate cyclase coupling, decreased in the hypertensive subjects from 38.0% +/- 3.8% when they were receiving 10 mmol/day sodium to 29.6% +/- 2.7% when they were receiving 250 mmol/day sodium (p less than 0.01). However, the proportion increased from 32.4% +/- 3.7% for normotensive subjects receiving 10 mmol/day sodium to 47.1% +/- 7.8% for normotensive subjects receiving 250 mmol/day sodium (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2004

Variability in respiratory protection and the assigned protection factor.

The workplace protection factor (WPF) for a given respirator wearer shows substantial variability from wearing to wearing; this variability is commonly assumed to be lognormal in nature. Further, when multiple WPFs are measured for each of multiple wearers, the aggregated WPFs appear to follow a lognormal distribution. However, the analysis typically applied to WPF data does not apportion variability within versus between wearers. We present an analytical framework based on a normal random effects model of log-transformed penetration P values (P = 1/WPF). Data from seven studies of negative-pressure air-purifying half-mask respirators, and from two studies of hemlet-and-visor type powered air-purifying respirators were analyzed by the method of maximum likelihood in the context of the model. More specifically, analyses were performed for log-transformed P values and for logit-transformed P values. Parameter estimates included within-wearer and between-wearer variance components. In general, the within-wearer component dominated the between-wearer component. We also propose a method for establishing an assigned protection factor, APF, that properly accounts for these variance components. Our method provides an APF satisfying two criteria: (1) for a given wearer, an acceptable WPF distribution has no more than 5% of WPFs below the APF value; and (2) for a wearer population, no more than 5% of wearers have unacceptable WPF distributions. The method incorporates an one-sided confidence limit to account for sampling variability. Alternative confidence limits were computed based on large sample variance estimates of random effects model parameters versus a bootstrap method. In general, there was good agreement between the APF values based on log-transformed versus logit-transformed P data, and between APF values based on the large sample variance estimates versus the bootstrap method. Based on large sample variance estimates for the logit-transformed P data from the seven half-mask studies, estimated APFs ranged from 1.4 to 250, with 5/7 studies yielding an APF </= 5.3. Given these results and related considerations, we recommend that the current half-mask APF be reduced from 10 to 5.

Air Pollution, Indoor↗
PubMed1991

Protective efficacy of neonatal Bacillus Calmette-Guérin vaccination against tuberculosis.

This matched case-control study was performed in two hospitals in Bangkok to evaluate the protective efficacy of neonatal Bacillus Calmette-Guérin (BCG) vaccination in Thai children and to find factors that might explain the reported variation in estimates of the protective efficacy of BCG. Cases were defined as children 3 months to 14 years of age who had tuberculosis and controls consisted of one to four children who were born in the same year and had the same district of residence as the case. A matched analysis with a variable number of controls per case was performed on 75 cases and 207 controls. Conditional logistic regression was performed to adjust for the potential confounding effects of household tuberculosis exposure and socioeconomic status. Forty-eight percent of cases had nonrespiratory tuberculosis. Laboratory-confirmed evidence for tuberculosis was found in 48% of cases. The adjusted protective efficacy of neonatal BCG vaccination was 83% (95% confidence limits, 35%, 96%). It was 96% (95% confidence limits, 66%, 100%) when only 36 matched sets of laboratory-confirmed cases were analyzed. Subgroup analyses and literature reviews indicated that the accuracy of tuberculosis diagnosis, types of tuberculosis, duration after vaccination and household tuberculosis exposure contribute to variation in the reported protective efficacy of neonatal BCG vaccination.

Adolescent↗
PubMed1990

Epidemiological evidence indicates asbestos causes laryngeal cancer.

A variety of opinions have been expressed in the literature concerning asbestos and laryngeal cancer. This paper presents an analysis of epidemiological studies based on criteria that prioritized the most heavily exposed cohorts. Emphasis was given to the six cohorts or subcohorts with lung cancer relative risk estimates of 2 or more. The two groups of workers with the highest lung cancer relative risk estimates (4.06 and 3.28) both gave strong support for a causal association of asbestos and laryngeal cancer, with relative risk estimates of 1.91 (90% confidence limits 1.00 to 3.34) and 3.75 (90% confidence limits 1.01 to 9.68), respectively. Confounding with cigarette smoking or alcohol consumption does not explain the findings. Case-control studies gave mixed results, but generally supported the hypothesis. It was concluded that asbestos is a probable cause of laryngeal cancer in view of the reasonable consistency of the studies, the strength of the association in key studies, the evidence for dose-response relationships, and the biological plausibility for asbestos being a cause of laryngeal cancer.

Alcoholic Beverages↗
PubMed2002

A low genomic number of recessive lethals in natural populations of bluefin killifish and zebrafish.

Despite the importance of selection against deleterious mutations in natural populations, reliable estimates of the genomic numbers of mutant alleles in wild populations are scarce. We found that, in wild-caught bluefin killifish Lucania goodei (Fundulidae) and wild-caught zebrafish Danio rerio (Cyprinidae), the average numbers of recessive lethal alleles per individual are 1.9 (95% confidence limits 1.3 to 2.6) and 1.4 (95% confidence limits 1.0 to 2.0), respectively. These results, together with data on several Drosophila species and on Xenopus laevis, show that phylogenetically distant animals with different genome sizes and numbers of genes carry similar numbers of lethal mutations.

Alleles↗
PubMed1997

High relapse rate among lepromatous leprosy patients treated with rifampin plus ofloxacin daily for 4 weeks.

Fifty-one lepromatous leprosy patients, all of whom had relapsed after previous dapsone (DDS) monotherapy, were treated between 1990 and 1991 with 600 mg of rifampin (RMP) plus 400 mg of ofloxacin (OFLO) daily for 4 weeks, and the great majority of the patients were followed up at least once a year after completion of the treatment. After only 173 patient-years of follow-up, 5 relapses had been detected; the overall relapse rate was 10.0% (confidence limits, 1.7 and 18.3%), or 2.9 relapses (confidence limits, 0.4 and 5.4) per 100 patient-years. The unacceptably high relapse rate indicated that 4 weeks of treatment with daily RMP-OFLO was unable to reduce the number of viable Mycobacterium leprae organisms to a negligible level. In addition, the M. leprae from one of the relapses were proved to have multiple resistance to DDS, RMP, and OFLO. To avoid further relapses, the follow-up was terminated and the great majority of the patients were retreated with the standard 2-year multidrug therapy from 1994. No further relapse has been diagnosed since the beginning of retreatment.

Adult↗
PubMed1988

Diagnostic accuracy of outpatient endocervical curettage using conventional and Vabra curettage of the cervix.

With the object of examining the diagnostic accuracy of and pain reaction to endocervical curettage (ECC) either by using a new instrument, Vabra mc cervix, or with a conventional 3 mm metal curette, 298 patients with histologically verified cervical intraepithelial neoplasia (CIN) or cytological suspicion have been involved in a consecutive prospective randomized trial. One hundred and forty-eight patients underwent curettage with the Vabra instrument (vabrasio) followed by conventional curettage; 150 underwent the same procedure, but in reverse order. In 114 patients, CIN was ascertained in one or both trials. Vabra mc cervix found normal histology in 23 of these patients (20%), whereas conventional curettage showed normal histology in 58 patients (51%). Quantitatively, Vabra mc cervix extracted significantly more tissue material than did conventional curettage. The pain intensity when using of Vabra mc cervix was less severe. The present study showed diagnostic accuracy of Vabra mc cervix to be 80% (95% confidence limits: 63.38-80.73), compared with 49% (95% confidence limits: 35.17-54.35) when using conventional curettage.

Ambulatory Surgical Procedures↗
PubMed1994

Effects of m-nisoldipine on contraction and 45Ca influx in isolated rat aorta.

m-Nisoldipine caused a concentration-dependent depression of the contractile response and 45Ca influx evoked by KCl in isolated rat thoracic aorta. The IC50 value for contraction and 45Ca influx were 0.69 (95% confidence limits 0.32-1.5) nmol.L-1 and 0.35 (95% confidence limits 0.06-2.0) nmol.L-1, respectively. There was a positive correlation between the inhibition of KCl-evoked contraction and 45Ca influx (r = 0.996). m-Nisoldipine (0.1-10 mumol.L-1) did not influence the 45Ca influx into resting cells and failed to inhibit noradrenaline (1.0 mumol.L-1)-evoked contraction and 45Ca influx. The results suggest that the relaxant effect of m-nisoldipine on rat aorta may be closely related to the blockade of Ca2+ entry through a potential-dependent calcium channel.

Animals↗
PubMed1993

Assessment of corticosteroid-induced alkaline phosphatase isoenzyme as a screening test for hyperadrenocorticism in dogs.

Quantitative determination of the corticosteroid-induced isoenzyme of alkaline phosphatase (CAP) was evaluated as a screening test for hyperadrenocorticism (HAC) in dogs. A series of 40 dogs with HAC (CAP range, 96 to 14,872 U/L), 30 clinically normal dogs (CAP range, 0 to 38 U/L), and 80 dogs with various diseases (non-HAC) and without history of exogenous glucocorticoid exposure for a minimum of 60 days (CAP range, 0 to 1163 U/L) were used to evaluate the test. Sensitivity and specificity of CAP was calculated at various cutoff points for absolute CAP activity and for CAP activity expressed as a percentage of total alkaline phosphatase activity. A cutoff point of 90 U/L was selected as optimal for use of this assay as a screening test for HAC. A prevalence survey then was done of all canine serum samples submitted to our diagnostic laboratory over a 3-month period, to calculate the predictive values of a positive and a negative test result in a clinical population and to determine the relative frequency and magnitude of CAP activity in dogs that had received glucocorticoids. The predictive values of a positive and a negative test result at the 90 U/L cutoff value were 21.43% (95% confidence limits, 8.3 to 40.95%) and 100% (95% confidence limit > 96%), respectively. It was concluded that CAP isoenzyme activity, determined by routine biochemical analysis by an automated levamisole-inhibition assay, could function as a screening test for HAC; however, the predictive value of a positive test result was too low to recommend the assay as a diagnostic test.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocortical Hyperfunction↗
PubMed1995

[Effects of tetrahydroprotoberberines on cytosolic free calcium in cultured rat single myocardial cells].

Effect of tetrahydroberberine (THB), l-tetrahydropalmatine (THP) and l-stepholidine (SPD) were supposed to be related to the blocking of calcium influx. In this paper, using Fura-2/AM and AR-CM-MIC cation measurement system, the effects of THB, THP and SPD on cytosolic free calcium ([Ca2+]i) in cultured rat single myocardial cells were examined and compared with verapamil (Ver). THB, THP and SPD (10-100 mumol.L-1) were found to increase resting [Ca2+]i gently, which was not depressed by tetrodotoxin. THB, THP and SPD (1-100 mumol.L-1) were also shown to inhibit the KCl-induced [Ca2+]i elevation, the IC50 values of THB and SPD were 50.9 (95% confidence limits: 18.5-140) mumol.L-1 and 23.5 (95% confidence limits 7.6-73.4) mumol.L-1, respectively. THB, THP and SPD 30 mumol.L-1 were also shown to inhibit the elevation of [Ca2+]i induced by high extracellular calcium and norepinephrine; but the inhibitory effects of these drugs were weaker than those of Ver. The three compounds showed no significant effect on ouabain induced [Ca2+]i increase. These results suggest that the inhibitory effects of THB, THP and SPD on [Ca2+]i in myocite by blocking voltage-dependent calcium channels were similar but inferior to Ver.

Animals↗
PubMed1997

Lack of pharmacokinetic interaction of meloxicam with methotrexate in patients with rheumatoid arthritis.

OBJECTIVE: To investigate the pharmacokinetic interaction of oral meloxicam with intravenous (i.v.) methotrexate (MTX) in patients with rheumatoid arthritis (RA). METHODS: Thirteen patients with RA received MTX 15 mg i.v. in the absence of nonsteroidal antiinflammatory drugs (NSAID) and after one week in the presence of steady state levels of meloxicam. Plasma concentrations of MTX and meloxicam were determined using validated high performance liquid chromatography methods. One patient did not complete the study. The interaction of meloxicam and MTX was examined by equivalence testing. The endpoints AUCMTX, VssMTX, CltotMTX, and CmaxMTX were analyzed parametrically, whereas endpoints MRTMTX, CltotMTX, t1/2MTX, and tmaxMTX were analyzed nonparametrically. RESULTS: The MTX plasma concentrations over time, with and without meloxicam, did not differ significantly. The point estimator for the ratio of log transformed data of the primary endpoint AUCMTX was 108%; the lower 95% confidence limit was 100% and the upper 95% confidence limit was 117%. Clinical laboratory values and adverse events revealed no increased MTX toxicity during concomitant treatment with meloxicam. CONCLUSION: In this short term interaction study there was no statistically significantly effect of meloxicam on the pharmacokinetics of MTX. The combination of MTX and meloxicam did not lead to increased MTX toxicity.

Adolescent↗
PubMed1994

Criteria for diagnosing anthelmintic resistance by the faecal egg count reduction test.

This study examines the possible outcome of adopting criteria recommended by the Australian Working Party for defining anthelmintic resistance by the faecal egg count reduction test, namely a mean percentage reduction of less than 95%, together with a lower 95% confidence limit of less than or equal to 90%. Based on an analysis of 313 veterinary diagnostic cases submitted for faecal egg count reduction testing in sheep and goats over a 7-year period, it was found that lower confidence limits of 90% or less were always associated with mean percentage reductions of less than 95%. These results suggest that if anthelmintic resistance is to be defined on the basis of mean faecal egg count reductions of this magnitude, then little practical purpose is likely to be served by further consideration of the lower confidence limits of these estimates.

Journal Article↗
PubMed1993

Variation of Cmax and Cmax/AUC in investigations of bioequivalence.

In order to enable the setting of regulatory criteria for the equivalence of absorption rates on a sound scientific basis, the variation of Cmax/AUC and Cmax was evaluated. Under most conditions, the variation of Cmax/AUC was 10-25% higher than that of AUC independently of the variability of the extent of absorption. By contrast, the variation of Cmax was 50-60% higher than that of AUC and was strongly dependent on the variability of the extent of absorption. Therefore, it is recommended that for establishing the equivalence of absorption rates, the 90% confidence limits for the percentage ratio of the Cmax/AUC values of two drug products should be (based on their logarithmic averages or medians) between 75 and 133%. Regulatory decisions based on Cmax, while not favored, should expect that the 90% confidence limits for the percentage ratio of the Cmax values of two drug products be (based on their logarithmic averages or medians) between 70 and 143%. These recommendations parallel and are contingent upon the internationally harmonized criterion for the equivalence of extents of absorption which requires that the 90% confidence limits for the percentage ratio of two AUC values (based on their logarithmic averages or medians) be between 80 and 125%.

Absorption↗
PubMed1999

Level of physical activity and the risk of radiographic and symptomatic knee osteoarthritis in the elderly: the Framingham study.

PURPOSE: Because osteoarthritis may be caused by "wear and tear," we examined the association between level of physical activity and risk of knee osteoarthritis in the elderly. SUBJECTS AND METHODS: Eligible subjects were participants in the Framingham Heart Study cohort who had radiographically normal knees at biennial exam 18 (1983-1985) and who also completed a physical activity questionnaire at exam 20 (1988-1989). Follow-up knee radiographs were obtained at biennial exam 22 (1992-1993). The study outcomes were the development of incident radiographic or symptomatic knee osteoarthritis between the baseline and follow-up exams. RESULTS: The number of hours per day of heavy physical activity was associated with the risk of incident radiographic knee osteoarthritis (odds ratio = 1.3 per hour, 95% confidence limits 1.1-1.6, P for trend = 0.006). Adjustment for age, sex, body mass index, weight loss, knee injury, health status, total calorie intake, and smoking strengthened this association (eg, odds ratio for > or = 4 hours heavy physical activity/day compared with no heavy physical activity = 7.0, 95% confidence limits 2.4-20, P for trend = 0.0002). Risk was greatest among individuals in the upper tertile of body mass index (odds ratio for > or = 3 hours/day of heavy physical activity = 13.0, 95% confidence limits 3.3-51). For incident symptomatic knee osteoarthritis, the results were similar, although the number of cases was small. No effects on these outcomes were observed from moderate and light physical activity, number of blocks walked, or number of flights of stairs climbed daily. CONCLUSIONS: Heavy physical activity is an important risk factor for the development of knee osteoarthritis in the elderly, especially among obese individuals. Light and moderate activities do not appear to increase risk.

Aged↗
PubMed1984

Sclerotherapy after first variceal hemorrhage in cirrhosis. A randomized multicenter trial.

At the time of their first hemorrhage from esophageal varices, 187 unselected patients with cirrhosis were randomly assigned to medical treatment including balloon tamponade or to medical treatment supplemented with intensive, paravariceal sclerotherapy. Follow-up period ranged from 9 to 52 months. The overall mortality in the sclerotherapy group (hazard) was 76 per cent (95 per cent confidence limits, 54 to 107 per cent) of that in the medical-regimen group. The relative mortality in the sclerotherapy group, determined by stratifying according to degree of encephalopathy and ascites, was 63 per cent of that in the medical-regimen group (95 per cent confidence limits, 44 to 91 per cent). The main effect of sclerotherapy may be a reduction of long-term mortality, which after Day 40 was only 43 per cent (95 per cent confidence limits, 23 to 79 per cent) of that in the medical-regimen group. Sclerotherapy had no significant influence on the initial hemorrhage as judged from the duration of bleeding or of balloon tamponade, the number of blood transfusions needed, or immediate mortality. Forty-five patients in the sclerotherapy group had 64 episodes of recurrent hemorrhage, as compared with 138 episodes among 51 patients in the medical-regimen group. This difference was due to a pronounced reduction of rebleeding after Day 40 in the sclerotherapy group. We recommend sclerotherapy for patients with cirrhosis who have bleeding from esophageal varices.

Adult↗