TAS1R- and TAS2R-type taste receptors are expressed in the gustatory system, where they detect sweet- and bitter-tasting stimuli, respectively. These receptors are also expressed in subsets of cells within the mammalian gastrointestinal tract, where they mediate nutrient assimilation and endocrine responses. For example, sweeteners stimulate taste receptors on the surface of gut enteroendocrine L cells to elicit an increase in intracellular Ca2+ and secretion of the incretin hormone glucagon-like peptide-1 (GLP-1), an important modulator of insulin biosynthesis and secretion. Because of the importance of taste receptors in the regulation of food intake and the alimentary responses to chemostimuli, we hypothesized that differences in taste receptor efficacy may impact glucose homeostasis. To address this issue, we initiated a candidate gene study within the Amish Family Diabetes Study and assessed the association of taste receptor variants with indicators of glucose dysregulation, including a diagnosis of type 2 diabetes mellitus and high levels of blood glucose and insulin during an oral glucose tolerance test. We report that a TAS2R haplotype is associated with altered glucose and insulin homeostasis. We also found that one SNP within this haplotype disrupts normal responses of a single receptor, TAS2R9, to its cognate ligands ofloxacin, procainamide and pirenzapine. Together, these findings suggest that a functionally compromised TAS2R receptor negatively impacts glucose homeostasis, providing an important link between alimentary chemosensation and metabolic disease.

Insensitivity to the bitter-tasting compound 6-n-propylthiouracil (PROP) has been proposed as a marker for individual differences in taste perception that influence food preference and intake. The principal genetic determinants of phenotypic variation in PROP taste sensitivity are alleles of the TAS2R38 gene, which encodes a chemosensory receptor sensitive to thiourea compounds including PROP and phenylthiocarbamide. Members of the TAS2R family are expressed in the gustatory system, where they function as bitter taste receptors, and throughout the gut, where their physiological roles in prandial, gut-derived hormone release are beginning to be elucidated. To better understand the relationship between TAS2R function and ingestive behaviors, we asked if TAS2R38 variants are associated with one or more of three eating behaviors: restraint, disinhibition, and hunger. We genotyped a single nucleotide polymorphism (SNP) located within the TAS2R38 gene, rs1726866 (T785C, Val262Ala) in 729 nondiabetic individuals (381 females, 348 males) within the Amish Family Diabetes Study. Eating behaviors were assessed using the Three-Factor Eating Questionnaire. An association analysis between rs1726866 and these three traits revealed a significant association of the PROP-insensitive “T” allele with increased disinhibition (p = 0.03). Because eating behaviors differ substantially between males and females, we subsequently performed sex-stratified analyses, which revealed a strong association in females (p = 0.0002) but not in males. Analyses with other SNPs in close proximity to rs1726866 suggest that this locus is principally responsible for the association. Therefore, our results indicate that a polymorphism in TAS2R38 is associated with differences in ingestive behavior.

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This project changed practice by substituting last-image capture for digital-spot images without affecting vesicoureteral reflux grading while reducing radiation exposure. Monitoring DAP is a better assessment of radiation exposure than is fluoroscopy time.

Although the prevalence of malignancy in average risk women under age 40 presenting with a palpable breast abnormality is low, the management of benign‐appearing palpable abnormalities remains controversial. This study assesses the imaging evaluation, subsequent management, and outcomes of women under age 40 presenting with a palpable area of concern. This study also evaluates the costs, utility, and outcomes of BI‐RADS 3 assessment in this patient population. A single institution retrospective case review from July 2010 through June 2013 identified women under age 40 presenting with a new palpable breast abnormality. Diagnostic imaging evaluation was performed. BI‐RADS assessments and recommendations were recorded prospectively. Outcome was determined by tissue diagnosis, 2 years of surveillance, or search of the hospital tumor registry. Performance measures were calculated. Among 1440 cases, 1052 were initially assessed as BI‐RADS 1 or 2 (73.1%), 184 as BI‐RADS 3 (12.8%), 182 as BI‐RADS 4 (12.6%), and 22 as BI‐RADS 5 (1.5%). In all, 30 breast malignancies were diagnosed (cancer yield 2.1%). All 30 cancers were initially categorized as BI‐RADS 4 or 5. No BI‐RADS 1, 2, or 3 findings proved malignant. The imaging evaluation sensitivity was 100%, specificity was 87.7%, and accuracy was 87.9%. The negative predictive value was 100% and the positive predictive value was 14.7%. Average risk women under age 40 presenting with a palpable abnormality have a low prevalence of breast cancer. Imaging evaluation has a high sensitivity and negative predictive value, thereby allowing for confident characterization and appropriate management recommendations. For palpable solid masses with benign imaging features in women under age 40, short‐term interval follow‐up with subsequent periodic imaging or clinical examination for a total of 2 years is a cost‐effective and safe alternative to biopsy.