In re Phillip B. 8 May 1979.
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The debate concerning the legal and ethical bases of guardian refusal of medical treatment on behalf of incompetent patients often ignores critical distinctions among types of patients and guardians. For example, patients who have expressed preferences regarding treatment while competent are distinguishable from patients who have always lacked the competency requisite to expressing a treatment preference. "Bonded guardians," whose relationship with the patient preexisted guardianship, should have a different role in the decision-making process than "non-bonded guardians," who were strangers to the patient prior to the guardian-ward relationship. This Article proposes criteria for guardian treatment refusal on behalf of incompetent patients. Under the model for guardian decision making presented here, bonded guardians should be preferred over non-bonded guardians, and bonded guardians should be allowed discretion to make treatment choices, limited only by a standard of reasonableness policed by the courts. The Author presents legal and ethical justifications for the bonded guardian's heightened role. Finally, he considers the proper roles of health professionals, hospital ethics committees, and judges in the decision-making process.
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Increased fetal lung expansion, induced by tracheal obstruction (TO), is a potent stimulus for fetal lung growth, but rapidly reduces surfactant protein (SP) mRNA levels. Our aim was to determine the time course for the re-expression of the surfactant proteins in fetal lung tissue following the release of a TO and to relate these to the changes in lung liquid volume. Fetal sheep were exposed to either: (1) no treatment (controls); (2) 4 days of TO; (3) 4 days of TO, followed by release of the obstruction for 24 h; (4) 4 days of TO followed by release of the obstruction for 3 days. Four days of TO increased lung liquid volumes from 26.8 +/- 1.9 to 72.0 +/- 5.6 ml kg(-1) and reduced SP-A, SP-B and SP-C mRNA levels to 38.5 +/- 10.7, 56.8 +/- 10.3 and 18.3 +/- 5.3 % of control values, respectively. One day after TO release, lung liquid volumes were reduced to 17.4 +/- 5.3 ml kg(-1) (control 128 days, 31.0 +/- 3.8 ml kg(-1)) and SP-A and SP-B mRNA levels were not different from control levels. In contrast, SP-C mRNA levels only increased to 45.4 +/- 17.3 % of control. Three days after TO release, lung liquid volumes increased to 48.0 +/- 8.5 ml kg(-1) and SP-A and SP-B mRNA levels were reduced to 48.8 +/- 10.2 % and 71.5 +/- 19.8 % of control, respectively; SP-C mRNA levels remained at 35.3 +/- 12.3 % of control. Following the release of a TO, SP-A, SP-B and SP-C mRNA levels were closely and inversely related to the volume of lung liquid. Based on these relationships, the lung liquid volumes that equate to 100 % expression were considerably less than control lung volumes (< 10 vs. 30-40 ml kg(-1)) in fetuses of this age. Thus, the changes in fetal lung SP-A, SP-B and SP-C mRNA levels following the release of a TO are variable, differ between the proteins and are closely related to the changes in lung liquid volumes. We conclude that the re-expression of surfactant proteins following TO is variable and that the change in lung liquid volume is potentially a good indicator for surfactant protein re-expression. Experimental Physiology (2001) 86.1, 55-63.
Mitochondrial DNA heteroplasmy using the protein-coding cytochrome b (Mtcyb) gene was assessed in laboratory mice (C57BL/6 and BALB/c) exposed to the Chernobyl environment. Subacute to subchronic (30-40 days) exposure resulted in a cumulative radiation dose of 1.2-1.6 Gy ( approximately 0.04 Gy/day). Mice were sampled prior to introduction into the enclosures and again after removal from the enclosures. Nucleotide variation (site heteroplasmy) in 306 pre-exposure Mtcyb gene copies (122400 base pairs) was compared to variation in 354 postexposure gene copies (141600 base pairs). Five mutant copies, each characterized by a single nucleotide substitution, were observed (four in the pre-exposure samples, one in a postexposure sample). The frequencies of mutant gene copies and nucleotide substitutions in pre-exposure and postexposure samples were not significantly different. This suggests that this type of exposure (i.e. low dose rate) does not pose a significant mutation risk to the Mtcyb gene in digit tissue. Furthermore, no significant radiation risk to analogous human tissues may exist when occupational exposures involve low dose rates such as these. Finally, linear, cumulative models of genetic risk currently used to estimate radiation-induced effects are likely to be inappropriate for low-dose-rate exposures and need to be re-evaluated critically.
BACKGROUND: Planning clinical-endpoint trials in patients with HIV remain difficult as long-term follow-up of many patients is required. Cohort studies of patients with HIV can provide key estimates of the likely disease progression, required sample size and follow-up. OBJECTIVES: To verify the assumptions used in designing ESPRIT, a large randomized clinical trial assessing the clinical benefit of interleukin-2 treatment in patients with HIV infection, to use EuroSIDA to mimic the inclusion criterion of ESPRIT in order to compare the observed event rate in ESPRIT with the projected rate in EuroSIDA, and to project the required length of ESPRIT. METHODS: Patients in EuroSIDA who satisfied the ESPRIT recruitment criteria were selected. Patients were followed from baseline to new AIDS or death. RESULTS: The incidence of clinical progression in the selected EuroSIDA patients (N = 4482) was 1.5 per 100 PYFU (95% CI 1.3-1.7), and did not increase with increasing time from baseline, contrary to what was assumed in the design of the ESPRIT trial. In ESPRIT (N = 4150), for which the comparative data remain blinded, the incidence was 1.1 per 100 PYFU (95% CI 0.9-1.3), with no increase over time. The average follow-up required to complete ESPRIT and accrue the 320 events required by protocol would be seven years, 10 months using the projected rates from the EuroSIDA study, and seven years, 11 months if the observed event rate in ESPRIT continued unchanged. LIMITATIONS: Differences between patients recruited to observational studies or clinical trials cannot always be adjusted for. CONCLUSIONS: Event rates in EuroSIDA were similar in the first two years to those used in the design of ESPRIT, but did not increase over time, leading to an increase in the expected duration of ESPRIT. Clinical endpoint trials in HIV infection remain feasible, and large cohort studies are critical to the planning and ongoing assessment of design assumptions in such trials. The underlying assumptions of the clinical trial should be re-examined to ensure the original trial assumptions remain valid.
OBJECTIVES: The differentiation of constitutional delayed puberty (CDP) from gonadotrophin deficiency (GD) in boys at referral poses a difficult challenge. The effectiveness of the GnRH agonist (GnRH-a) test in distinguishing between the two conditions was evaluated and compared with findings of the GnRH and hCG stimulation tests. PATIENTS, METHODS AND DESIGN: The study sample included 32 prepubertal boys aged 14 years or older. Thirteen entered spontaneous puberty within 1 year of referral (group A) and 19 remained prepubertal (group B). All underwent the GnRH test (Relefact, Hoechst AG, 0.1 mg/m2 i.v. in one bolus), GnRH-a test (Decapeptyl, Ferring GmbH, 0.1 mg/m2 s.c.) and hCG stimulation (Chorigon, Teva, 1500 units i.m. on three alternate days) at 1-week intervals. All tests were performed at referral at 0800 h. Blood samples were collected before testing and at 30 and 60 min (GnRH test) or 4 h (GnRH-a) for LH and FSH determination, and before testing and at 4 h (GnRH-a) or on the seventh day (hCG) after stimulation for serum testosterone measurement. RESULTS: The LH response to GnRH-a and the testosterone response to hCG stimulation were significantly higher in group A (LH, mean +/- SD 20.4 +/- 7.5 mIU/ml, range 10.8-32.6; testosterone, mean +/- SD 18.0 +/- 5.9 nmol/l, range 9.4-26, P < 0.0001) than in group B (LH, mean +/- SD 2.3 +/- 2.0 mIU/ml, range 0.7-6.9; testosterone, mean +/- SD 1.0 +/- 0.7 nmol/l, range 0.7-3.2), with no overlap between the groups. The cut-off for the LH response to GnRH-a was 8.0 mIU/ml, and for the testosterone response to hCG, 8 nmol/l. There were also significant differences between the groups in mean basal serum LH and FSH (LH, 1.1 +/- 0.5 vs. 0.6 +/- 0.2 mIU/ml, P < 0.05; FSH, 2.2 +/- 2.0 vs. 0.4 +/- 0.3 mIU/ml, P < 0.02) and their response to GnRH (LH, 11.4 +/- 4.4 vs. 2.7 +/- 1.1 mIU/ml, P < 0.0001; FSH, 5.1 +/- 3.4 vs. 2.5 +/- 2.4 mIU/ml, P < 0.0001), and mean serum testosterone level at 4 h after GnRH-a administration (1.9 +/- 1.0 vs. 0.9 +/- 0.4 nmol/l, P = 0.002), but all showed a great overlap in range. Mean age, testicular volume and basal serum testosterone levels were similar in the two groups at referral. One year later, the testicular volume of group A (5.0-12.0 ml) was significantly larger than that of group B (1.0-3.0 ml, P < 0.0001), which remained unchanged on re-examination 3.0 +/- 0.5 years later. CONCLUSIONS: The GnRH-agonist test and the repeated-injection hCG test are reliable diagnostic tools for differentiating CDP from GD in boys.
This report shows that the urethral lumen cross-sectional shape is complex but slit-like and it is suggested that this shape is related to function. A radiological method for determining urethral shape during micturition has been developed and compared with histological studies. The lumen is markedly non-circular even during micturition. Simple theoretical analysis of preliminary shapes shows that current concepts of urethral flow are incomplete and urethral pressure profile measurements require re-evaluation. The function of accepted sphincter mechanisms requires a slit-like lumen. Lumen shape is a fundamental property of the urethra, the clinical importance of which has yet to be explored.