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The illegal practice of using cyanide (CN) as a stunning agent to collect fish for both the marine aquarium and live fish food trades has been used throughout the Indo-Pacific for over 50 years. CN fishing is destructive to all life forms within the coral reef ecosystems where it is used and is certainly one of many anthropogenic activities that have led to 95% of the reefs in the Indo-Pacific being labeled at risk for degradation and loss. A field-deployable test for detecting fish caught using CN would assist in combating the use of this destructive practice, however, no reliable and robust test exists. Further, there is little toxicokinetic data available on marine fish to support the development of such a test, yet such data is critical to establishing the concentration range and time scale over which such a test would be viable. This study presents the first direct measurement of the half-life of the metabolite thiocyanate (SCN) after pulsed exposure to CN in a marine fish. SCN was measured in the plasma of Amphiprion ocellaris after exposure to 50 ppm CN for three exposure times (20, 45, and 60 s) using HPLC-UV and a C30 column pre-treated with polyethylene glycol. Plasma SCN levels observed are dose-dependent, reflecting a longer time for conversion of CN to SCN as the dose of CN increases. SCN plasma levels reached a maximum concentration (1.2-2.3 ppm) 12-20 h after exposure to CN. The half-life for the elimination of SCN was 1.01 ± 0.26 days for 45 s exposure and 0.44 ± 0.15 days for 20 s exposure. Fish were also directly exposed to SCN (100 ppm for 11 days) and the observed half-life for SCN elimination was 0.35 ± 0.07 days. Plasma SCN levels did not return to control levels, even after 41 days when exposed to CN but did return to control levels after 48 days when exposed to SCN. The similar half-lives observed for CN and SCN exposure suggests that SCN exposure can be used as a proxy for measuring the rate of SCN elimination following CN exposure. In order for plasma SCN to be used as a marker for CN exposure, these results must be extended to other species and endogenous levels of SCN in wild caught fish must be established.

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PURPOSE: The aim of this study was to better assess the prevalence and appearance of thymic tissue in adults stratified by age using multidetector computed tomography (MDCT) in order to prevent misinterpretation of normal thymic tissue as pathology. MATERIALS AND METHODS: This study examined the CT appearance of the thymus in 597 trauma patients aged 30 to 69 years (M=48.0 y, SD=11.3). Three body fellowship-trained attending radiologists independently reviewed the CT scans. Reviewers assigned one of 5 grades on the basis of the relative proportions of fat and soft tissue in the thymic bed: complete fatty replacement (grade 0), predominantly fat (grade 1), even mix of soft tissue and fat (grade 2), predominantly soft tissue (grade 3), and discrete confluent thymic tissue (grade 4). Objectively, fixed-area region of interest values of the thymic bed were obtained. Interrater reliability was calculated. RESULTS: Increased fatty replacement of the thymus occurred with increasing age. We found residual thymic tissue (≥grade 1) in the following age categories: 30 to 39 years (83.0%), 40 to 49 years (71.9%), 50 to 59 years (52.6%), and 60 to 69 years (34.8%). Kappa comparisons for the entire sample were excellent (κ=0.86). Higher grades had higher region of interest values. CONCLUSIONS: Residual thymic tissue in adults on MDCT is both more prevalent and more prominent than that reported in earlier studies and can be visible into the seventh decade. We recommend that radiologists and clinicians familiarize themselves with the normal range appearances of the thymus on MDCT, in order to prevent misinterpretation of normal thymic tissue as pathology, which may result in unnecessary procedures.

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Several years ago, our community teaching hospital identified a need to improve patient care by streamlining the study performance workflow and hastening communication of critical study results to clinicians. "STAT" studies are a carefully selected subset of imaging studies that are prioritized due to their utility in assessing for emergent conditions including cerebrovascular accidents, pneumoperitoneum, and cardiac arrest. We describe the multiyear process of data collection, analysis, and departmental and hospital-wide system changes that significantly improved result times. Relatively simple policy changes, such as the distribution of STAT beepers to the team members and creating color-coded worklists, drastically reduced delays.

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OBJECTIVE: The purpose of our study was to determine the efficacy of contrast-enhanced CT in detecting a thickened endometrium. We used transvaginal sonography as the reference standard. MATERIALS AND METHODS: Between March 2005 and January 2007, data from 259 patients (mean age, 47 years; age range, 18-90 years) who underwent transvaginal sonography and contrast-enhanced CT of the pelvis were analyzed retrospectively. The endometrium was quantitatively measured in millimeters on sonography. On CT it was qualitatively categorized as normal, thickened, indeterminate, or not visualized and compared with the sonography findings and original radiology reports. When the endometrium was indeterminate (thickened or triangular in shape on axial images), sagittal reconstructions were performed for final categorization. Two reviewers evaluated the CT scans and sonograms jointly with differences resolved by consensus. Kappa, Wilcoxon's rank sum test, and intraclass correlation statistics were derived. RESULTS: The overall sensitivity and specificity of CT in detecting the thickened endometrium was 53.1% and 93.5%, respectively, relative to transvaginal sonography. The positive and negative predictive values were 66.7% and 89.1%, respectively. Kappa, the statistical measure of agreement between CT and sonography data, was 0.5049. All cases of a triangular endometrium were normal in size on sagittal reconstruction images. CONCLUSION: Routine pelvic CT correctly identifies a normal endometrium in most patients. Sagittal reconstruction images are helpful to further evaluate the endometrium on CT in cases with a prominent or triangular endometrium because these are often related to uterine version. CT is relatively insensitive in detecting the thickened endometrium but better able to identify gross rather than subtle thickening, which must be further characterized by transvaginal sonography.

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Farmworkers are exposed to pesticides and may take home pesticide residues to their families. In this paper, self-reported pesticide exposure and home practices to reduce the amount of pesticide residues taken home were examined among 571 farmworkers. Urine samples from a subsample of farmworkers and children and dust samples from households and vehicles also assessed pesticide exposure. Overall, 96% of respondents reported exposure to pesticides at work. Many employers did not provide resources for hand washing. Farmworkers' protective practices to keep pesticide residues out of the home were at a low level. In a subset of respondents, pesticide levels above the limit of quantitation were seen in the urine of children and adults and in house and vehicle dust. The results support the take-home pathway of pesticide exposure. Ways must be found to reduce this pesticide exposure among children of farmworkers.

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Population-based cancer registries rely on various methods to assign Hispanic ethnic identifiers to patients in the registry. The methods may result in misclassification of patient ethnic identities. Such misclassification may obscure the real incidence of cervical cancer among Hispanic women. This review summarizes previous literature on the accuracy of methods used to ascertain Hispanic ethnicity in numerator and denominator data for the calculation of cancer incidence. In addition, cancer registry ethnicity ascertainment methods were examined for six United States states (California, Florida, Illinois, New Mexico, New York, and Texas) that have a high proportion of Hispanics. The percentage of persons classified as Hispanic who self-identified as Hispanic (predictive value positive) in various reported studies ranged from 54 to 76% for women. The accuracy of ethnicity assignments based on either the United States census list or the Generally Useful Ethnic Search System (GUESS) program show slight differences in percentages of self-identified Hispanics who were classified as Hispanic (sensitivity among women: 62-80% for 1980 United States census list, 63-82% for GUESS program). Higher sensitivity and lower predictive value positive is achieved with a greater number of sources used. In conclusion, decisions about collecting racial and ethnicity information are influenced by demographic changes, immigration trends, changes in ethnic and racial identity, legislative needs, and public policies. The rapidly growing Hispanic population and the excess incidence of cervical cancer in this population requires improving the accuracy of ethnicity information.

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