Development and validation testing of a weight management nutrition knowledge questionnaire for adults.

BACKGROUND/OBJECTIVES: Because no validated tool exists to assess nutrition knowledge regarding weight management we developed and tested the Weight Management Nutrition Knowledge Questionnaire (WMNKQ). SUBJECTS/METHODS: The questionnaire assesses nutrition knowledge in these categories: energy density of food, portion size/serving size, alcohol and sugar sweetened beverages, how food variety affects food intake, and reliable nutrition information sources. In total 60 questions were reviewed by 6 experts for face validity and quantitative analysis was used to assess item difficulty, item discrimination, internal consistency, inter-item-correlation, test-retest reliability, construct validity, criterion validity, and convergent validity. RESULTS: The final WMNKQ contained 43 items. Experts removed 3 of the original 60 questions and modified 41. Eighteen items did not meet criteria for item difficulty, item discrimination, and/or inter-item correlation; 4 were retained. The WMNKQ met criteria for internal consistency (Cronbach's alpha = 0.88), reliability (test-retest correlation ρ = 0.90, P < 0.0001), construct validity (known groups comparison) - dietitians scored 16% better (p < 0.0001) than information technology workers, and criterion validity (pre- to post-intervention improvement in knowledge scores = 11.2% (95% CI 9.8-12.5, p < 0.0001)). Participants younger than age 55 scored significantly better than those over age 55 (convergent validity). CONCLUSIONS: The WMNKQ measures how well nutrition principles of weight management are understood.

The pro-fibrotic role of dipeptidyl peptidase 4 in carbon tetrachloride-induced experimental liver injury.

Liver fibrosis is a progressive pathological process involving inflammation and extracellular matrix deposition. Dipeptidyl peptidase 4 (DPP4), also known as CD26, is a cell surface glycoprotein and serine protease. DPP4 binds to fibronectin, can inactivate specific chemokines, incretin hormone and neuropeptides, and influences cell adhesion and migration. Such properties suggest a pro-fibrotic role for this peptidase but this hypothesis needs in vivo examination. Experimental liver injury was induced with carbon tetrachloride (CCl4) in DPP4 gene knockout (gko) mice. DPP4 gko had less liver fibrosis and inflammation and fewer B cell clusters than wild type mice in the fibrosis model. DPP4 inhibitor-treated mice also developed less liver fibrosis. DNA microarray and PCR showed that many immunoglobulin (Ig) genes and some metabolism-associated transcripts were differentially expressed in the gko strain compared with wild type. CCl4-treated DPP4 gko livers had more IgM+ and IgG+ intrahepatic lymphocytes, and fewer CD4+, IgD+ and CD21+ intrahepatic lymphocytes. These data suggest that DPP4 is pro-fibrotic in CCl4-induced liver fibrosis and that the mechanisms of DPP4 pro-fibrotic action include energy metabolism, B cells, NK cells and CD4+ cells.

Dipeptidyl peptidase 9 enzymatic activity influences the expression of neonatal metabolic genes.

The success of dipeptidyl peptidase 4 (DPP4) inhibition as a type 2 diabetes therapy has encouraged deeper examination of the post-proline DPP enzymes. DPP9 has been implicated in immunoregulation, disease pathogenesis and metabolism. The DPP9 enzyme-inactive (Dpp9 gene knock-in; Dpp9 gki) mouse displays neonatal lethality, suggesting that DPP9 enzyme activity is essential in neonatal development. Here we present gene expression patterns in these Dpp9 gki neonatal mice. Taqman PCR arrays and sequential qPCR assays on neonatal liver and gut revealed differential expression of genes involved in cell growth, innate immunity and metabolic pathways including long-chain-fatty-acid uptake and esterification, long-chain fatty acyl-CoA binding, trafficking and transport into mitochondria, lipoprotein metabolism, adipokine transport and gluconeogenesis in the Dpp9 gki mice compared to wild type. In a liver cell line, Dpp9 knockdown increased AMP-activated protein kinase phosphorylation, which suggests a potential mechanism. DPP9 protein levels in liver cells were altered by treatment with EGF, HGF, insulin or palmitate, suggesting potential natural DPP9 regulators. These gene expression analyses of a mouse strain deficient in DPP9 enzyme activity show, for the first time, that DPP9 enzyme activity regulates metabolic pathways in neonatal liver and gut.

Expert consensus on priority research gaps in dietary and lifestyle factors in hidradenitis suppurativa: a Delphi consensus study.

Hidradenitis suppurativa (HS) is a debilitating systemic inflammatory disease with limited treatment options. Although management through dietary and lifestyle changes is a primary interest of the HS patient community, there is lack of consensus regarding recommendations due to the paucity of evidence. To establish the priority research gaps on this topic, we performed and moderated a Delphi consensus study by integrating expert opinions and the relevant literature. Based on a literature review, research questions on dietary and lifestyle interventions in HS were constructed. HS dietary and lifestyle research questions were sent to an expert panel, consisting of 22 international members, including dermatologists, dietitians, pharmacists, and endocrinologists. Voting on the research questions was conducted using a modified Delphi technique. The primary outcome measure was whether participants could reach consensus on the priority of each research question in the HS dietary and lifestyle factors. After three rounds of surveys investigating the relationships between HS and various diet and lifestyle factors, "BMI", "Obesity", and "Smoking", reached consensus as high priority research questions. Low research priorities per consensus included "effects of iron supplements", "effects of magnesium supplements", "alcohol consumption" and "limiting Brewer's yeast intake. Smoking and obesity were identified as important research questions, concurrent to the literature indicating their association with more significant impact on disease activity. By shedding light on high priority research questions, our study provides a roadmap for further research on dietary and lifestyle modifications in HS and will help determine evidence-based lifestyle and dietary recommendations for patients with HS.

Immune regeneration in irradiated mice is not impaired by the absence of DPP9 enzymatic activity.

The ubiquitous intracellular protease dipeptidyl peptidase 9 (DPP9) has roles in antigen presentation and B cell signaling. To investigate the importance of DPP9 in immune regeneration, primary and secondary chimeric mice were created in irradiated recipients using fetal liver cells and adult bone marrow cells, respectively, using wild-type (WT) and DPP9 gene-knockin (DPP9S729A) enzyme-inactive mice. Immune cell reconstitution was assessed at 6 and 16 weeks post-transplant. Primary chimeric mice successfully regenerated neutrophils, natural killer, T and B cells, irrespective of donor cell genotype. There were no significant differences in total myeloid cell or neutrophil numbers between DPP9-WT and DPP9S729A-reconstituted mice. In secondary chimeric mice, cells of DPP9S729A-origin cells displayed enhanced engraftment compared to WT. However, we observed no differences in myeloid or lymphoid lineage reconstitution between WT and DPP9S729A donors, indicating that hematopoietic stem cell (HSC) engraftment and self-renewal is not diminished by the absence of DPP9 enzymatic activity. This is the first report on transplantation of bone marrow cells that lack DPP9 enzymatic activity.

Clinical management after bariatric surgery: value of a multidisciplinary approach.

Comprehensive and collaborative longitudinal care is essential for optimal outcomes after bariatric surgery. This approach is important to manage the many potential surgical and medical comorbidities in patients who undergo bariatric surgery. Medical management programs require prompt and often frequent adjustment as the nutritional program changes and as weight loss occurs. Familiarity with the recommended nutritional program, monitoring and treatment of potential vitamin and mineral deficiencies, effects of weight loss on medical comorbid conditions, and common postoperative surgical issues should allow clinicians to provide excellent care. Patients must understand the importance of regularly scheduled medical follow-up to minimize potentially serious medical and surgical complications. Because the long-term success of bariatric surgery relies on patients' ability to make sustained lifestyle changes in nutrition and physical activity, we highlight the role of these 2 modalities in their overall care. Our guidelines are based on clinical studies, when available, combined with our extensive clinical experience. We present our multidisciplinary approach to postoperative care that is provided after bariatric surgery and that builds on our presurgical evaluation.

Neuropeptide Y is a physiological substrate of fibroblast activation protein: Enzyme kinetics in blood plasma and expression of Y2R and Y5R in human liver cirrhosis and hepatocellular carcinoma.

Fibroblast activation protein (FAP) is a dipeptidyl peptidase (DPP) and endopeptidase that is weakly expressed in normal adult human tissues but is greatly up-regulated in activated mesenchymal cells of tumors and chronically injured tissue. The identities and locations of target substrates of FAP are poorly defined, in contrast to the related protease DPP4. This study is the first to characterize the physiological substrate repertoire of the DPP activity of endogenous FAP present in plasma. Four substrates, neuropeptide Y (NPY), peptide YY, B-type natriuretic peptide and substance P, were analyzed by mass spectrometry following proteolysis in human or mouse plasma, and by in vivo localization in human liver tissues with cirrhosis and hepatocellular carcinoma (HCC). NPY was the most efficiently cleaved substrate of both human and mouse FAP, whereas all four peptides were efficiently cleaved by endogenous DPP4, indicating that the in vivo degradomes of FAP and DPP4 differ. All detectable DPP-specific proteolysis and C-terminal processing of these neuropeptides was attributable to FAP and DPP4, and plasma kallikrein, respectively, highlighting their combined physiological significance in the regulation of these neuropeptides. In cirrhotic liver and HCC, NPY and its receptor Y2R, but not Y5R, were increased in hepatocytes near the parenchymal-stromal interface where there is an opportunity to interact with FAP expressed on nearby activated mesenchymal cells in the stroma. These novel findings provide insights into the substrate specificity of FAP, which differs greatly from DPP4, and reveal a potential function for FAP in neuropeptide regulation within liver and cancer biology.

Targeted inactivation of dipeptidyl peptidase 9 enzymatic activity causes mouse neonate lethality.

Dipeptidyl Peptidase (DPP) 4 and related dipeptidyl peptidases are emerging as current and potential therapeutic targets. DPP9 is an intracellular protease that is regulated by redox status and by SUMO1. DPP9 can influence antigen processing, epidermal growth factor (EGF)-mediated signaling and tumor biology. We made the first gene knock-in (gki) mouse with a serine to alanine point mutation at the DPP9 active site (S729A). Weaned heterozygote DPP9 (wt/S729A) pups from 110 intercrosses were indistinguishable from wild-type littermates. No homozygote DPP9 (S729A/S729A) weaned mice were detected. DPP9 (S729A/S729A) homozygote embryos, which were morphologically indistinguishable from their wild-type littermate embryos at embryonic day (ED) 12.5 to ED 17.5, were born live but these neonates died within 8 to 24 hours of birth. All neonates suckled and contained milk spots and were of similar body weight. No gender differences were seen. No histological or DPP9 immunostaining pattern differences were seen between genotypes in embryos and neonates. Mouse embryonic fibroblasts (MEFs) from DPP9 (S729A/S729A) ED13.5 embryos and neonate DPP9 (S729A/S729A) mouse livers collected within 6 hours after birth had levels of DPP9 protein and DPP9-related proteases that were similar to wild-type but had less DPP9/DPP8-derived activity. These data confirmed the absence of DPP9 enzymatic activity due to the presence of the serine to alanine mutation and no compensation from related proteases. These novel findings suggest that DPP9 enzymatic activity is essential for early neonatal survival in mice.

Quantitation of fibroblast activation protein (FAP)-specific protease activity in mouse, baboon and human fluids and organs.

The protease fibroblast activation protein (FAP) is a specific marker of activated mesenchymal cells in tumour stroma and fibrotic liver. A specific, reliable FAP enzyme assay has been lacking. FAP's unique and restricted cleavage of the post proline bond was exploited to generate a new specific substrate to quantify FAP enzyme activity. This sensitive assay detected no FAP activity in any tissue or fluid of FAP gene knockout mice, thus confirming assay specificity. Circulating FAP activity was ∼20- and 1.3-fold less in baboon than in mouse and human plasma, respectively. Serum and plasma contained comparable FAP activity. In mice, the highest levels of FAP activity were in uterus, pancreas, submaxillary gland and skin, whereas the lowest levels were in brain, prostate, leukocytes and testis. Baboon organs high in FAP activity included skin, epididymis, bladder, colon, adipose tissue, nerve and tongue. FAP activity was greatly elevated in tumours and associated lymph nodes and in fungal-infected skin of unhealthy baboons. FAP activity was 14- to 18-fold greater in cirrhotic than in non-diseased human liver, and circulating FAP activity was almost doubled in alcoholic cirrhosis. Parallel DPP4 measurements concorded with the literature, except for the novel finding of high DPP4 activity in bile. The new FAP enzyme assay is the first to be thoroughly characterised and shows that FAP activity is measurable in most organs and at high levels in some. This new assay is a robust tool for specific quantitation of FAP enzyme activity in both preclinical and clinical samples, particularly liver fibrosis.

Combined group and individual model for postbariatric surgery follow-up care.

BACKGROUND: The prevalence of bariatric surgery in the United States has increased significantly during the past decade, increasing the number of patients requiring postbariatric surgery follow-up care. Our objective was to develop and implement an efficient, financially viable, postbariatric surgery practice model that would be acceptable to patients. The setting was the Mayo Clinic (Rochester, MN). METHODS: By monitoring the attendance rates and using patient surveys, we tested patient acceptance of a new, shared medical appointment practice model in the care of postbariatric surgery patients. Efficiency was assessed by comparing differences in time per patient and total provider time required between the former and new care models. Individual-only patient/provider visits were replaced by combined group and individual visits (CGV). RESULTS: Our CGV model was well-attended and accepted. The patient attendance rate was >90% at all postoperative follow-up points. Furthermore, 83%, 85.2%, and 75.7% of the 3-, 6-, and 12-month postbariatric surgery patients, respectively, responded that they would not prefer to have only individual visits with their healthcare providers. The CGV model also resulted in greater time efficiency and cost reduction. On average, 5 patients were seen within 4.9 provider hours compared with 10.4 provider hours with the individual-only patient/provider visit model. Furthermore, the average billable charge for the CGV model's group medical nutrition therapy was 50-64% less than the equivalent individual medical nutrition therapy used in the individual-only patient/provider visit model. CONCLUSION: Shared medical appointments have a valuable role in the care of the postbariatric surgery population, offering a time- and cost-effective model for healthcare provision that is well-accepted by patients.

The in vivo expression of dipeptidyl peptidases 8 and 9.

The dipeptidyl peptidase IV (DPIV) enzyme family contains both potential and proven therapeutic targets. Recent reports indicate the presence of DP8 and DP9 in peripheral blood lymphocytes, testis, lung, and brain. For a more comprehensive understanding of DP8 and DP9 tissue and cellular expression, mRNA and enzyme activity were examined. Many organs from C57BL/6 wild-type and DPIV gene-knockout mice were examined; DP8/9 enzyme activity was detected in the immune system, brain, testis, muscle, and epithelia. In situ hybridization localized DP8 and DP9 mRNA to lymphocytes and epithelial cells in liver, gastrointestinal tract, lymph node, spleen, and lung. DP8 and DP9 mRNA was detected in baboon and mouse testis, and DP9 expression was elevated in human testicular cancers. DP8 and DP9 mRNA were ubiquitous in day 17 mouse embryo, with greatest expression in epithelium (skin and gastrointestinal tract) and brain. Thus, DP8 and DP9 are widely expressed enzymes. Their expression in lymphocytes and epithelia indicates potential for roles in the digestive and immune systems. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.