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Summary The study was initiated as an in vitro approach to the situation existing during intravesical bacillus Calmette-Guerin (BCG) instillation in patients with superficial bladder cancer. Cytokine secretion of a human bladder carcinoma cell line T24 treated with BCG was investigated. A 24-h treatment of T24 cells with BCG resulted in a tenfold higher secretion of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF) when compared with T24 cells treated with Escherichia coli, Streptococcus faecalis or a cell wall preparation of Nocardia rubra (N-CWS). No secretion of IL-1 and IL-2 was detected. Pre-exposing T24 cells to BCG for various periods of time indicated that a minimum exposure time of 0.5–1 h was required to upregulate IL-6 and TNF production. Extending the BCG pre-exposure time to 2 and 3 h further increased the rate of cytokine production. No significant difference was found, however, between the rate of secretion initiated after a 2-h or 3-h pre-exposure period. The amounts of these cytokines secreted in the presence of BCG-conditioned medium did not differ significantly from the constitutively secreted amounts, excluding an effect of products possibly secreted by BCG on the upregulation of IL-6 and TNF. In addition, upregulation of cytokine production appeared to be dependent on the concentration of BCG. The results suggest that cytokines may be produced by urothelial tumor cells after intravesical instillation in patients with superficial bladder cancer, which may play a role in the mode of action of BCG.  相似文献   
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RATIONALE AND OBJECTIVES: To understand normal bone development, studies in healthy children and adolescents are important. To assess the applicability of tibial quantitative ultrasound measurements (QUS) in children, we performed a study that compared dual-energy x-ray absorptiometry (DXA) of the lumbar spine and whole body with tibial QUS. METHODS: For this study we recruited 146 Dutch children and adolescents, 58 boys (median age, 14.1 years; range, 7.6-23.4 years) and 88 girls (median age, 18.0 years; range, 7.6-23.5 years). Tanner stage, weight, and height were assessed for all participants. Bone mineral density (BMD; g x cm(-2)) of the whole body and lumbar spine (L2-L4) and bone mineral apparent density (BMAD) of the lumbar spine (g x cm(-3)) were assessed by using the Lunar DPXL. For tibial QUS, the Soundscan compact system was used. RESULTS: Both lumbar as well as whole-body BMD showed a strong, significant correlation with tibial QUS in boys and girls: rtotal body boys = 0.81, rtotal body girls = 0.77, rlumbar spine boys = 0.79, and rlumbar spine girls = 0.72. Lumbar spine BMAD also showed significant correlations with tibial QUS: rboys= 0.63 and rgirls = 0.63 (for all correlations, P < 0.001). CONCLUSIONS: Our study showing strong, significant correlations between DXA and tibial QUS measurements suggests that tibial QUS is a technique that may be applicable in children and adolescents.  相似文献   
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CONTEXT: In Turner syndrome (TS), GH treatment is well established. Data on cardiac status after discontinuation of treatment are scarce. This study aimed to assess biventricular size and function in TS at least 6 months after discontinuation of GH treatment. METHODS: TS patients and healthy women prospectively underwent cardiac magnetic resonance imaging. Ventricular two-dimensional tomographic cine data were acquired to obtain biventricular volume, mass, and ejection fraction. Atrioventricular valve flow measurements were performed using a two-dimensional flow-sensitized sequence. Flow velocity curves were calculated and indices of biventricular diastolic filling were derived. RESULTS: Thirty-one patients [mean (sd) age 20 (2) yr, body surface area 1.75 (0.15) m(2), 5 (2) yr after GH discontinuation] and 23 normal control women [age 21 (2) yr, body surface area 1.80 (0.13) m(2)] were included. Compared with controls, patients had smaller mean end-diastolic volumes [right ventricle (RV), 84 (11) ml/m(2) vs. 79 (10), P = 0.02; left ventricle (LV), 81 (10) vs. 72 (9), P < 0.001], end-systolic volumes [RV 38 (7) ml/m(2) vs. 36 (6), P = 0.04; LV 34 (5) vs. 29 (4), P < 0.001], and stroke volumes [RV 46 (6) ml/m(2) vs. 43 (6), P = 0.03; LV, 47 (7) vs. 44 (4), P = 0.02]. Patients had a higher mean heart rate [79 (13) beats/min vs. 71 (10), P < 0.05]. Biventricular ejection fraction, mass, cardiac output, and diastolic filling pattern were comparable. CONCLUSION: After discontinuation of GH treatment TS patients showed no myocardial hypertrophy and well-preserved biventricular function. Ventricular volumes were smaller in Turner patients, compared with controls, whereas mean heart rate was higher. These last observations may be part of the natural development in TS and not linked to GH treatment, which at this point we consider safe.  相似文献   
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Background

The Patient-rated Wrist Evaluation (PRWE) is a commonly used instrument in upper extremity surgery and in research. However, to recognize a treatment effect expressed as a change in PRWE, it is important to be aware of the minimum clinically important difference (MCID) and the minimum detectable change (MDC). The MCID of an outcome tool like the PRWE is defined as the smallest change in a score that is likely to be appreciated by a patient as an important change, while the MDC is defined as the smallest amount of change that can be detected by an outcome measure. A numerical change in score that is less than the MCID, even when statistically significant, does not represent a true clinically relevant change. To our knowledge, the MCID and MDC of the PRWE have not been determined in patients with distal radius fractures.

Questions/Purposes

We asked: (1) What is the MCID of the PRWE score for patients with distal radius fractures? (2) What is the MDC of the PRWE?

Methods

Our prospective cohort study included 102 patients with a distal radius fracture and a median age of 59 years (interquartile range [IQR], 48–66 years). All patients completed the PRWE questionnaire during each of two separate visits. At the second visit, patients were asked to indicate the degree of clinical change they appreciated since the previous visit. Accordingly, patients were categorized in two groups: (1) minimally improved or (2) no change. The groups were used to anchor the changes observed in the PRWE score to patients’ perspectives of what was clinically important. We determined the MCID using an anchor-based receiver operator characteristic method. In this context, the change in the PRWE score was considered a diagnostic test, and the anchor (minimally improved or no change as noted by the patients from visit to visit) was the gold standard. The optimal receiver operator characteristic cutoff point calculated with the Youden index reflected the value of the MCID.

Results

In our study, the MCID of the PRWE was 11.5 points. The area under the curve was 0.54 (95% CI, 0.37–0.70) for the pain subscale and 0.71 (95% CI, 0.57−0.85) for the function subscale. We determined the MDC to be 11.0 points.

Conclusions

We determined the MCID of the PRWE score for patients with distal radius fractures using the anchor-based approach and verified that the MDC of the PRWE was sufficiently small to detect our MCID.

Clinical Relevance

We recommend using an improvement on the PRWE of more than 11.5 points as the smallest clinically relevant difference when evaluating the effects of treatments and when performing sample-size calculations on studies of distal radius fractures.  相似文献   
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OBJECTIVE We have studied the effect of treatment with high doses of androgens during puberty on testicular function In adult men with constitutionally tall stature, taking Into account confounding factors interfering with sperm quality, since existing published data do not include whether testicular function is impaired by such treatment. DESIGN Historical cohort study. PATIENTS Forty-three previously androgen treated tall men (cases) and 30 non-treated tall men (controls). MEASUREMENTS Physical examination, semen analysis and plasma levels of LH, FSH, testosterone (T), sex hormone binding globulin (SHBG) and Inhlbin. RESULTS Sperm quality and testis volume were comparable between cases and controls. Mean sperm concentration was 66.4 ± 106/ml in cases and 66.2 ± 106/ml in controls. A left-sided varicocele was found In 45% of the cases and 37% of the controls. In cases we observed a significant effect of the age at start of androgen therapy on sperm motility (regr. coeff. (SE): 4.92 (2.41)%, P= 0.048). In addition, testicular size at start of therapy had a significant effect on sperm concentration (regr. coeff. (SE): 5.57 (1.54) ± 106/ml, P= 0.0012) and on total sperm count (regr. coeff. (SE): 43.1 (7.73) ± 106, P= 0.0001). Plasma levels of T, SHBG and Inhibin were not statistically different between the groups. Cases had significantly higher FSH levels (mean (SD) 3.3 (2.2) vs 2.1 (0-8) IU/I, P= 0.004) and significantly lower LH levels (mean (SD) 2.3 (0.9) vs 3.1 (1.4) IU/I, P= 0.019). We found a significant effect of age at start of therapy on plasma FSH level In the treated men (regr. coeff. (SE): ?0.73 (0.18) IU/I, P= 0.0003). CONCLUSIONS Treatment with high doses of androgens for reduction of final height in constitutionally tall stature has no long-term side-effect on sperm quality, testicular volume or plasma testosterone levels. However, treated men had significantly higher plasma levels of FSH compared with controls. The meaning of this difference remains to be established. Varicocele was present in 42% of the adult tall men.  相似文献   
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The effective flow rates with human blood through an autoperfusion catheter cannot be monitored in vivo and have not been experimentally determined in vitro. The manufacturers (Advanced Cardiovascular Systems [ACS], Temecula, CA) have suggested that “the flow rate” through the Stack over the wire and the RX-60 monorail catheter is 60 ml/min with a pressure gradient of 80 mmHg. We measured human blood flow rates in vitro through these catheters under different continuous pressure regimens (between 40 and 120 mmHg), with varying hematocrit levels (between 25% and 62%). Measured blood flows at a gradient of 80 mmHg were found to vary from 32 to 65 cc/min, with hematocrit levels of 62-25%. Minor variations in the circuitry, besides the viscosity of the medium, cause significant changes in observed flow rates (such as kinking of the catheter and blood sedimentation). In vitro determinations of blood flows cannot automatically be transferred to the in vivo condition, primarily because in vitro determinations do not account for the systolic intramural pressure increase (which may overcome the aortic pressure). If such a phenomenon is also considered, then the in vitro flow rates reported here should be multiplied by a factor of 0.40–0.60 to determine effective in vivo flow rates. Such information is relevant for the clinical operator of angioplasty, especially in the treatment of patients at high risk for undergoing percutaneous transluminal coronary angioplasty. © 1993 Wiiey-Liss, Inc.  相似文献   
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Experimental and clinical studies are progressing simultaneously to investigate the mechanisms and efficacy of progenitor cell treatment after an acute myocardial infarction and in chronic congestive heart failure. Multipotent progenitor cells appear to be capable of improving cardiac perfusion and/or function; however, the mechanisms still are unclear, and the issue of whether or not trans-differentiation occurs remains unsettled. Both experimentally and clinically, cells originating from different tissues have been shown capable of restoring cardiac function, but more recently multiple groups have identified resident cardiac progenitor cells that seem to participate in regenerating the heart after injury. Clinically, cells originating from blood or bone marrow have been proven to be safe whereas injection of skeletal myoblasts has been associated with the occurrence of ventricular arrhythmias. Myoblasts can transform into rapidly beating myotubes; however, thus far convincing evidence for electro-mechanical coupling between myoblasts and cardiomyocytes is lacking. Moving forward, mechanistic studies will benefit from the use of genetic markers and Cre/lox reporter systems that are less prone to misinterpretation than fluorescent antibodies, and a more convincing answer regarding therapeutic efficacy will come from adequately powered randomized placebo controlled trials.  相似文献   
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