Technique and use of transbronchial biopsy in children and adolescents.

Since July 1988, a total of 92 transbronchial biopsies (TBB) have been performed in 18 patients (aged 3-16 years). Twelve patients (67%) were heart-lung transplant (HLT) recipients undergoing surveillance for pulmonary graft rejection and infection. The remainder included immunocompromised patients at risk of opportunistic infections (n = 4), patients with fibrosing alveolitis (n = 1) and a collagen vascular disorder with suspected lung involvement (n = 1). TBB was performed through either a fiberoptic (n = 50) or a rigid (n = 41) bronchoscope, all under general anesthesia. On one occasion a cardiac bioptome was used through an endotracheal stent. The sensitivity of TBB for diagnosing acute and chronic rejection in HLT patients was 88% and 60%, respectively (specificity, 91% and 100%). Definitive diagnoses were made in 4 (67%) of the non-HLT group. Bronchoalveolar lavage (BAL) was performed during each procedure for microbiological and cytological examination. Thirty-four pathogenic organisms including Pseudomonas aeruginosa (16/34), Staphylococcus aureus (8/34), and Candida albicans (5/34) were isolated from BAL culture. Complications included pneumothorax (8%), transient pyrexia (7%), and dyspnea (2%).     

Metallic hip implants: CT with multiplanar reconstruction

Thirty consecutive patients with metallic implants in the hip were evaluated with both standard transaxial computed tomography (CT) and multiplanar reconstruction (MPR) to assess the contribution of MPR. The metallic devices included total hip replacements (n = 6), one or more surgical plates with screws (n = 9), acetabular pins or screws (n = 9), and Knowles pins (n = 6). The metallic implants were on the side of interest in 25 hips and in the contralateral hip in five cases. One patient had bilateral hardware. MPR reformats axially acquired data into other planes. The reconstruction program weights the true signal over the randomly distributed artifacts by integrating adjacent axial images. Examination using standard transaxial imaging was graded as excellent in five cases, adequate in 15 cases, and inadequate in ten cases. After MPR, 19 studies were classified as excellent, 11 were classified as adequate, and none were classified as inadequate. It is concluded that MPR significantly reduced artifacts caused by metal present in transaxial images.     

The pressor response to central administration of beta-endorphin results from a centrally mediated increase in noradrenaline release and adrenaline secretion.

1. The effects of intracerebroventricular (i.c.v.) and intracisternal (i.c.) administration of beta-endorphin (0.01, 0.1 and 1.0 nmol kg-1) were examined in conscious rabbits. 2. After i.c.v. beta-endorphin, mean arterial pressure (MAP) increased, heart rate (HR) fell, plasma noradrenaline, adrenaline and glucose increased and there was a rise in PaCO2 and fall in PaO2; these effects were reversed by intravenous (i.v.) naloxone (300 nmol kg-1). 3. A combination of prazosin (2 mg kg-1) and yohimbine (1 mg kg-1), given i.v., prevented the rise in MAP induced by i.c.v. beta-endorphin. 4. After i.c. beta-endorphin, MAP, HR and plasma catecholamines were not significantly altered but there was a similar degree of respiratory depression. 5. Clonidine (1.0 micrograms kg-1, i.c.) reduced MAP and HR; these effects were not blocked by i.v. naloxone (6 mumol kg-1). 6. These results demonstrate that beta-endorphin acts centrally, probably mainly on periventricular mu-opioid receptors, to increase adrenaline secretion and sympathetic nerve activity leading to alpha-adrenoceptor-mediated vasoconstriction. The respiratory depression is probably mediated by brainstem mu-receptors. 7. A role for beta-endorphin in the central hypotensive action of alpha 2-adrenoceptor agonists was opposed by finding that opioid receptor antagonism with naloxone did not block the effects of clonidine.     

Phase II trial of high-dose intermittent interleukin-2 in metastatic renal cell carcinoma: a Southwest Oncology Group study

A phase II trial of intermittent high-dose recombinant interleukin-2 (rIL-2) was initiated to evaluate the response rate, remission duration, and toxic effects in patients with measurable metastatic renal cell carcinoma. The rIL-2 was administered as a bolus intravenous infusion at a dose level of 10.0 x 10(6) U/m2 three times weekly, preceded by indomethacin (50 mg orally). Dose reductions of rIL-2 for hypotension and other grade 3 or 4 toxic effects were permitted. Forty-four patients were entered and 41 were eligible. Previous treatment included nephrectomy (23 patients), radiation therapy (seven), and hormone therapy (three). Most toxic effects observed were moderate and included nausea, vomiting, anorexia (85%); hypotension (85%); fever, chills (78%); central nervous system changes (24%); myelosuppression (27%); and creatinine elevation (15%). Four instances of grade 4 toxicity were observed and included nausea, vomiting with dehydration; hypotension; and myocardial infarction. Thirty patients (73%) required dose adjustments because of toxicity. Five responses (12%) were seen, which included one complete and four partial. Sites of response included lung, liver, and soft tissue; the duration of response ranged from 2 to 20+ months. These results demonstrate that this schedule of rIL-2 can be administered in an outpatient setting, and can produce tumor regression in patients with metastatic renal cell carcinoma, including durable complete responses.     

An investigation into the effect of different intakes of vitamin C on drug metabolism in Gambian men

Hepatic mixed-function oxidase activity was measured in Gambian men during a period of low seasonal vitamin C intake and after vitamin C supplementation. Demethylation of methoxyphenylacetamide (methacetin) was followed using a breath test, in which the exhalation of 13C-enriched CO2 was measured following an oral dose of 13C-methacetin. Vitamin C supplementation, sufficient to increase plasma levels significantly, did not influence methacetin metabolism. However, methacetin metabolism in unsupplemented men appeared normal in the majority of cases. Hepatic tissue may not have been sufficiently depleted of vitamin C to impair the activity of the mixed function oxidase system.     

Coarctation of the aorta: MR imaging

Thirteen patients, aged 3-31 years, with coarctation of the thoracic aorta were examined by magnetic resonance (MR) imaging (total of 14 studies). Eight studies were performed preoperatively and six postoperatively. Catheterization data were available on 12 patients for verification of MR imaging findings. Electrocardiographically gated sagittal and left anterior oblique images best depicted the coarctations; however, involvement of arch vessels was best evaluated on transaxial images. MR imaging readily identified all coarctations but one, their site and extent, and involvement of the arch vessels. In addition, MR images depicted poststenotic dilatation and dilated collateral vessels. In patients studied postoperatively, restenosis could be evaluated, and complications such as postoperative aneurysm and perianastomotic hematoma were identified. MR imaging provides excellent anatomic detail of coarctation of the aorta, potentially obviating the need for angiography.     

A survey of actinic keratoses among paraquat production workers and a nonexposed friend reference group

Follow-up on two reports of an excess of keratoses among paraquat production workers was conducted to evaluate the contribution of occupational exposures to the prevalence of keratoses among workers in a paraquat production plant in Texas. A cross-sectional study design was used to compare the prevalence of keratoses among current workers to an age, race, and sex frequency-matched group of their friends who had never worked at the plant. The analysis is based on 112 workers and 232 friends. Exposure, outcome, and covariables used in the analyses were obtained from an interview questionnaire, dermatology exam, and company records. Overall, the prevalence proportion of the presence of any actinic keratoses among workers and friends was similar (0.30 and 0.28, respectively). Among high cumulative exposed workers, the prevalence of any actinic keratoses was 0.40 compared to 0.20 among low-exposed workers and 0.28 among friends. These results were further explored using a multiple logistic regression approach to adjust for known risk and possibly confounding variables. Statistically significant high risks of actinic keratoses were demonstrated for freckling before age 16 years, older age, suntanning behaviors, occupational exposure to polycyclic aromatic hydrocarbons (PAH), and Fitzpatrick skin type. There was no significant contribution of overall exposure status (worker vs. friend). Similar to the crude analysis, the odds of actinic keratoses of high-exposed workers compared to friends was 1.9 (confidence interval [CI] = 0.9-4.2) whereas the comparable odds ratio for low-exposed workers vs. friends was 0.6 (CI = 0.2–1.7). These data do not demonstrate an excess of actinic keratoses overall nor any consistent increase in the odds of keratoses with an increase in plant exposure level. © 1994 Wiley-Liss, Inc.     

Research and treatment: the need for a combined effort

Institutional, ideological, practical, and logistical constraints have impeded treatment research efforts in the substance abuse fields. There is a need for innovation in the design and conduct of treatment research studies, including studies that are less restrictive of therapists' judgments and more sensitive to individual client differences. Among the advantages of a greater collaboration between clinicians and researchers are the facilitation of research on the matching of clients to treatments and the enhanced impact of research findings on clinical practice.