ObjectiveEarly detection and early treatment are of vital importance to the successful treatment of various cancers. The development of a novel screening method that is as economical and non-invasive as the faecal occult blood test (FOBT) for early detection of colorectal cancer (CRC) is needed. A study was undertaken using canine scent detection to determine whether odour material can become an effective tool in CRC screening.DesignExhaled breath and watery stool samples were obtained from patients with CRC and from healthy controls prior to colonoscopy. Each test group consisted of one sample from a patient with CRC and four control samples from volunteers without cancer. These five samples were randomly and separately placed into five boxes. A Labrador retriever specially trained in scent detection of cancer and a handler cooperated in the tests. The dog first smelled a standard breath sample from a patient with CRC, then smelled each sample station and sat down in front of the station in which a cancer scent was detected.Results33 and 37 groups of breath and watery stool samples, respectively, were tested. Among patients with CRC and controls, the sensitivity of canine scent detection of breath samples compared with conventional diagnosis by colonoscopy was 0.91 and the specificity was 0.99. The sensitivity of canine scent detection of stool samples was 0.97 and the specificity was 0.99. The accuracy of canine scent detection was high even for early cancer. Canine scent detection was not confounded by current smoking, benign colorectal disease or inflammatory disease.ConclusionsThis study shows that a specific cancer scent does indeed exist and that cancer-specific chemical compounds may be circulating throughout the body. These odour materials may become effective tools in CRC screening. In the future, studies designed to identify cancer-specific volatile organic compounds will be important for the development of new methods for early detection of CRC.

Based on the evidence from our previous studies that we can evaluate the hydration state of the skin surface quickly and quantitatively in terms of conductance to the high frequency electric current of 3.5 MHz, we have established a simple in vivo function test that furnishes information on the hygroscopic property and water-holding capacity of the stratum corneum in a few minutes. The test procedure consists of electromeasurements before and after application of a droplet of water on the skin for 10 seconds to obtain data on the hygroscopic property of the skin surface and later serial measurements at an interval of 30 seconds for 2 min to evaluate the water-holding capacity. Under usual ambient conditions normal skin surface showed a high rise in conductance just after application of water, which was followed by a rapid fall-off within 30 seconds, thereafter by gradual return to the prehydration levels by 2 min. By this method we have demonstrated that (i) the superficial horny layer of normal skin is much less hygroscopic and less capable of holding water than the corresponding deeper portions and that (ii) scaly skin shows functional defects in both hygroscopicity and water-holding capacity, between which the former normalizes much faster than the latter.

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ABSTRACT. A murine model for short-chain acyl-coenzyme A dehydrogenase (SCAD) deficiency has been identified and characterized in BALBJcByJ mice. These mice have undetectable SCAD activity, severe organic aciduria; excreting ethylmalonic and methylsuccinic acids and Nbutyrylglycine, and develop a fatty liver upon fasting or dietary fat challenge. The mutant mice develop hypoglycemia after an 18-h fast, and have elevated urinary and muscle butyrylcarnitine concentrations. Most of these findings parallel those of human disorders associated with SCAD deficiency and other P-oxidation defects. This mouse model presents important opportunities to investigate the biology of mammalian fatty acid metabolism and the related human diseases. (Pediatr Res 25:38-43, 1989) Abbreviations SCAD, short-chain acyl-CoA dehydrogenase MCAD, medium-chain acyl-CoA dehydrogenase MCT, medium-chain triglycerides Deficiency of SCAD has been described recently in humans (1-4). The most severe form of this disorder is characterized by patients with episodes of metabolic acidosis, nonketotic hypoglycemia, and short-chain dicarboxylic aciduria. The clinical outcomes range from normalcy to unexpected death in homozygotes. Lately, sudden infant death syndrome and Reye's-like syndrome have been linked to defects in P-oxidation of fatty acids (5-7). Other recent studies have demonstrated that a secondary carnitine deficiency associated with the organic acidemia appears involved in the pathogenesis of the episodic events of these disorders (1,4,8). Overall, these diseases appear complex.We have a program to screen mice for inherited metabolic diseases (9) to develop models for investigating the pathogenesis and treatment of these disorders. In the course of screening mutant mice for organic acidurias using gas chromatographymass spectrometry, we discovered a subline of BALB/c mice (BALB/cByJ) that excreted unusually large concentrations of ethylmalonic and methylsuccinic acids and N-butyrylglycine. Butyryl-CoA dehydrogenase activity and electrophoretic mobility are used as a genetic marker for the Bcd-1 locus on mouse 38chromosome 5 (10). Subsequently, we learned that BALB/cByJ mice were found to have no detectable butyryl-CoA dehydrogenase activity by this marker assay (10). The null allele of these mice was designated Bcd-1" and was distinctly different from the normal activity associated with the Bcd-lb allele of BALB/cJ or BALB/cBy mice. To investigate the enzymatic defect and the resulting metabolic consequences, we performed a series of experiments using BALB/c By (Y) mice as controls and the BALB/ c ByJ (J) mutant mice. MATERIALS AND METHODSMice. BALB/cBy and BALB/cByJ mice were purchased from The Jackson Laboratory, (Bar Harbor, ME) and propagated at the Baylor College of Medicine (Houston, TX). All mice were maintained on Wayne rodent food no. 8640 (Wayne Pet Food Division, Continental Grain Co., Chicago, IL) and water ad libitum. Heterozygous mice were produced by crossing a Y female with a J male.Biochemistry. Urinary organic acids were ...