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Existing methods for assessing protein synthetic rates (PSRs) in human skeletal muscle are invasive and do not readily provide information about individual muscle groups. Recent studies in canine skeletal muscle yielded PSRs similar to results of simultaneous stable isotope measurements using L-[[I.sup.-13]C, [methyl-.sup.2][H.sub.3]] methionine, suggesting that positron-emission tomography (PET) with L-[[methyl.sup.11]C] methionine could be used along with blood sampling and a kinetic model to provide a less invasive, regional assessment of PSR. We have extended and refined this method in an investigation with healthy volunteers studied in the postabsorptive state. They received [approximately equal to] 25 mCi of L-[[methyl.sup.11]C]methionine with serial PET imaging of the thighs and arterial blood sampling for a period of 90 min. Tissue and metabolite-corrected arterial blood time activity curves were fitted to a three-compartment model. PSR (nmol methionine[multiplied by][min.sup.-1][multiplied by]g muscle [tissue.sup.-1]) was calculated from the fitted parameter values and the plasma methionine concentrations, assuming equal rates of protein synthesis and degradation. Pooled mean PSR for the anterior and posterior sites was 0.50 [+ or -] 0.040. When converted to a fractional synthesis rate for mixed proteins in muscle, assuming a protein-bound methionine content of muscle tissue, the value of 0.125 [+ or -] 0.01%[multiplied by][h.sup.-l] compares well with estimates from direct tracer incorporation studies, which generally range from [approximately equal to]0.05 to 0.09%[multiplied by][h.sup.-1]. We conclude that PET can be used to estimate skeletal muscle PSR in healthy human subjects and that it holds promise for future in vivo, noninvasive studies of the influences of physiological factors, pharmacological manipulations, and disease states on this important component of muscle protein turnover and balance.

Cholestatic jaundice associated with chills, pruritus and blood eosinophilia developed in a patient who received prajmalium bitartrate therapy for ventricular arrhythmia following acute myocardial infarction. Discontinuation of the drug resulted in a spontaneous improvement in the clinical and biochemical findings. Challenge by prajmalium bitartrate caused rapid reappearance of the clinical and biochemical features. In immunological studies, deposits of IgG and IgA were detected at the bile canaliculi by fluorescent staining, and the patient's lymphocytes produced macrophage migration inhibition after in vitro incubation with prajmalium bitartrate. Thus, laboratory results support the assumption of an allergic mechanism. [ABSTRACT FROM PUBLISHER]

It is suggested that tubulointerstitial nephritis and uveitis (TINU) is a cell-mediated immune disease with a favourable response to treatment with steroids. However, long-term follow-up has not been described and data on immunological studies are limited. The aim of this study was to evaluate the clinical features in patients with TINU who have had a long follow-up period, and in parallel to assess their cellular immunity and HLA typing. Four women with TINU were followed for 5.7±3.6 years. On remission they were studied for T-cell-mediated immunity by skin tests, T-cell subpopulations, and lymphokine secretion . The lymphokines included interleukin-2, γ-interferon, tumour necrosis factor, and colony-stimulating factor. The response to AS101, a previously described immunomodulator, was evaluated. HLA-typing was also performed. The nephritis, which occurred once, was resolved in all patients and did not recur. In contrast, numerous relapses of uveitis occurred despite topical or systemic steroid treatment. The patients' T-cell subpopulations did not differ from controls, but they revealed anergy to skin tests and a very low secretion rate of lymphokines. AS101 corrected the suppressed secretion . A high frequency of HLA-DR6 antigen was found in the TINU patients. TINU is probably a systemic disease with a chronic relapsing course of the uveitis but with complete clinical recovery of the nephritis. Both and T-cell functions are suppressed during remission. [ABSTRACT FROM PUBLISHER]

Previous studies in our laboratory on 92 patients with colonic cancer have suggested a promising degree of specificity and sensitivity for a macrophage migration inhibition factor (MIF) test using patient's lymphocytes incubated with a human colon cancer extract. This study compares the results of the MIF technique with serum carcinoembryonic antigen (CEA) levels and with the lymphocyte adherence inhibition (LAI) test in 18 colon cancer patients and 27 patients with conditions considered to predispose to colon cancer (colonic adenomas, ulcerative colitis, and Crohn's disease). Among colonic cancer patients, MIF and LAI were positive in 17 out of 18, but CEA was elevated in eight. MIF and CEA were negative in all 16 normal control subjects; LAI was negative in 13. Among patients with colonic adenomas, MIF and LAI were positive in three of five; CEA was negative in all. In the ulcerative colitis and Crohn's disease group, MIF was positive in seven of 22, LAI was positive in 11, and CEA was negative in all 22. Thus, MIF and LAI appear to be sensitive marker's for human colonic cancer. More extensive studies and precise characterization of these groups are warranted. [ABSTRACT FROM AUTHOR]

Since fatty acids provide the majority of myocardial energy requirements under basal conditions, an alteration in the global or regional utilization of these substrates may be an early indicator of myocardial disease. To determine areas of potential clinical utility of fatty acid imaging, we synthesized a radioiodinated modified fatty acid 14-(p-iodophenyl) beta methyltetradecanoic acid IPBMTA, which cannot undergo beta-oxidation. Preliminary biodistribution and imaging studies were performed in animals and man. These studies suggest that radioiodinated beta-methyl phenyl fatty acids localized rapidly in the myocardium and had prolonged myocardial retention time. The long residence time permits the recording of high quality planar and SPECT images. [ABSTRACT FROM PUBLISHER]