Practice setting and physician influences on judgments of colon cancer treatment by community physicians.

OBJECTIVE. This article compares judgments about the treatment of Dukes' B2 and C colon cancer made by general surgeons to those of internists and family practitioners. Physician and practice variables were specialty, affiliation with a Community Clinical Oncology Program (CCOP) hospital, time in practice, professional centrality (level of participation in cancer information networks), solo practice, and number of colon cancer patients. DATA COLLECTION METHODS. Data are combined from national probability samples of CCOP- and non-CCOP-affiliated physicians. This study focused on 1,138 internists, family physicians, and general surgeons who participated in decision making for patients diagnosed with Dukes' B2 or C stage colon cancer. Judgments were elicited using brief vignettes. METHODS OF ANALYSIS. Judgments of adjuvant therapy are classified as (a) consistent with the National Institutes of Health Consensus Conference recommendations (experimental for Dukes' B2, accepted for Dukes' C); (b) accepted treatment for both stages; or (c) experimental for both stages. Multinomial logit analyses were used to examine the association of practice setting and physician characteristics to judgments of treatment. RESULTS. Surgeons and CCOP-affiliated physicians were more likely to endorse the NIH consensus conference position. Surgeons, younger physicians, and those in group practice were more likely to approve of chemotherapy for both cancer stages. The most common position (chemotherapy experimental) was more likely from nonsurgeons, solo practitioners, and non-CCOP physicians. CONCLUSION. Physician and practice setting characteristics, including organized structures such as the CCOP, are possible mediating structures that can facilitate dissemination of standards of treatment.     

Induction of endothelium-dependent relaxation in the rat aorta by IRL 1620, a novel and selective agonist at the endothelin ETB receptor.

1. The effects of a novel and selective agonist at the endothelin ETB receptor, IRL 1620 (Suc-[Glu9, Ala11,15] endothelin-1 (8-21)), were examined in the isolated aorta of the rat. 2. IRL 1620 (1-300 nM) changed neither the resting tone nor the cytosolic Ca2+ level ([Ca2+]i) of the aorta without endothelium. In the presence of endothelium, however, IRL 1620 increased endothelial [Ca2+]i with little effect on the muscle tone. In the absence of external Ca2+, IRL 1620 still induced a transient increase in endothelial [Ca2+]i. 3. Noradrenaline (100 nM) increased both muscle [Ca2+]i and tension. IRL 1620 (1-300 nM) relaxed the muscle with an increase in endothelial [Ca2+]i only in the presence of endothelium. An inhibitor of nitric oxide synthase, 100 microM NG-monomethyl-L-arginine, inhibited the relaxant effect of IRL 1620 but not the increase in endothelial [Ca2+]i. 4. In resting and noradrenaline-stimulated aorta, the effects of IRL 1620 were inhibited by a selective antagonist of the ETB receptor, IRL 1038 (0.3-3 microM), although a selective antagonist of the ETA receptor, BQ-123 (3 microM), was ineffective. Verapamil (10 microM) did not alter the effects of IRL 1620. 5. A muscarinic receptor agonist, carbachol (1 microM), also induced endothelium-dependent relaxation with an increase in endothelial [Ca2+]i. However, the effects of carbachol were not inhibited by the ETB antagonist, IRL 1038 (3 microM).(ABSTRACT TRUNCATED AT 250 WORDS)     

Large granular lymphocyte expansions in patients with Felty's syndrome: analysis using anti-T cell receptor V beta-specific monoclonal antibodies.

Felty's syndrome (FS), the association of rheumatoid arthritis (RA) and idiopathic neutropenia, remains an unexplained phenomenon. HLA-DR4 is found in over 90% of cases. Patients with FS may have a T cell lymphocytosis of CD3+CD8+CD57+ large granular lymphocytes (LGL syndrome). In this study of 47 patients with FS, 19% had clear evidence for LGL expansions, while in total 42% had variable evidence for the LGL syndrome using currently available techniques. Of these T cell expansions, 76% were clonal, as demonstrated by Southern blotting and analysis with T cell receptor (TCR) beta chain constant region probes. This technique may fail to detect clonal populations in some patients. Cytofluorographic analysis using antibodies specific for TCR V beta chains identified patients with clonal LGL expansions with results comparable to those obtained with Southern blotting. No evidence for shared V beta usage among expansions from different patients was seen. The role of LGL in RA and FS is currently unclear, but this technique offers a practical and accessible means of identifying patients with LGL expansions, as a starting point for further investigation.     

Problems and solutions of pedicle screw plate fixation of lumbar spine

Fifty-seven patients with low back pain and sciatica of various causes were reviewed with reference to problems associated with pedicle plate fixation of the lumbar spine. Eleven percent of patients had neurologic problems postoperatively and 3.5% (two patients) had severe sensory impairments. All patients had this complication in the early phases of the study. Of 297 screws, 17 broke, ie, 5.7%. These breakages occurred in 12 of 57 patients (21%). In patients with spondylolisthesis, the degree of slip correction averaged 53% postoperatively, which decreased to 35% at the 1-year follow-up. Slip angle was maintained after correction. Pedicle screw plate fixation is an effective form of immobilization of the lumbar spine used in achieving arthrodesis. The surgeon must be fully trained in methodology. It is recommended that screw and plate materials be improved to prevent screw breakage.     

Accessory left-ventricular chorda and the early ventricular repolarization syndrome

Electrocardiographic symptoms were evaluated in 53 patients with an additional left-ventricular chorda (ALVC), detected by two-dimensional echocardiography. Signs of early ventricular repolarization (EVR) were identified in 45 (84.9%) patients. A transverse ALVC was more common in EVR-free patients (87.5%), as compared to patients with ALVC + EVR combinations (51.1%; p less than 0.05).     

Hormonal effects of high dose medroxyprogesterone acetate treatment in males with renal or prostatic adenocarcinoma

In 18 patients, 12 with renal and 6 with prostatic carcinoma, the gonadal, pituitary and adrenal functions were studied by measurements of steroid hormones and gonadotrophins, before and after six weeks treatment with medroxyprogesterone acetate (MPA), injected intramuscularly 500 mg per day for 5 days each week. The testosterone-oestradiol-binding globulin (TeBg) was measured and the amount of albumin and TeBg bound and unbound testosterone was calculated. Treatment with high doses of MPA caused a profound decrease in serum concentrations of testosterone, dehydroepiandrosterone sulphate (DHEAS), cortisol and TeBg. There were significant decreases in serum concentrations of luteinizing hormone (LH), follicle stimulating hormone (FSH) and oestradiol-17 beta. The serum concentration of prolactin was significantly elevated. The protein unbound testosterone fraction was lowered by MPA treatment but less than total testosterone. In conclusion, MPA therapy in high dose alters the gonadal, pituitary and adrenal functions suppressing serum concentrations of androgens, gonadotrophins, cortisol and TeBg but elevating prolactin concentration.