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Background: Newly diagnosed patients with inflammatory bowel disease (IBD) encounter many physical, mental, and social uncertainties. In other chronic diseases, patients having access to disease-specific information and psychological support adhere better to medical regimens. Currently, there is a paucity of data on how newly diagnosed patients with IBD interact with their medical providers. Methods: Patients diagnosed with IBD within 5 years completed a series of questionnaires related to heath-related quality of life (HRQoL), disease activity, health education resources, medical provider relationship, and psychological support. Results: A total of 89 patients were included in the study. IBD activity correlated with disease-specific quality of life (r=−0.69, p

Novel phospholipid (PL)-cyclosporine conjugates were prepared and studied as potential prodrugs for inflammatory bowel disease (IBD). Our approach relies on phospholipase A2 (PLA2 ), which is overexpressed in the inflamed intestinal tissues, as the prodrug activator to potentially release cyclosporine at the site of inflammation. PL-cyclosporine prodrug conjugates with methylene linkers of various lengths between the sn-2 position of the PL and cyclosporine were synthesized and evaluated for in vitro activation. Surprisingly, despite previous work indicating that conjugates with six methylene linkers between the lipid and drug would suffer rapid enzymatic hydrolysis, with cyclosporine this was not observed. However, compounds with longer linkers (n=10, 12 methylene units) display complete release of the drug by PLA2 -catalyzed hydrolysis, thus demonstrating the importance and profound impact of structural fine-tuning. This study represents a proof-of-concept for our hypothesis and a first step towards a truly targeted IBD treatment with cyclosporine that could be administered throughout the GI tract.

Introduction: The social impact of inflammatory bowel disease (IBD) on student transition to college is significant, yet poorly understood. Methods: Two 90-min focus groups (FGs) were conducted with eight student-patients with IBD. Reflective journals were used to corroborate, elaborate, or challenge emergent FG findings. Results: Six themes emerged: (1) transitioning to college, (2) interacting with physicians, (3) affecting social life, (4) managing the disease by yourself and through support, (5) coping strategies, and (6) facing disease challenges. These themes remained relevant in the reflective writings. Analysis of serial journal entries showed that students' social life and engagement in coursework was affected 66% and 54% of the time, respectively. Conclusion: Our findings offer guidance for improving students' college success, quality of care, and enhancing physician–patient interactions. Students with IBD have a disability that may not be obvious or visible. They require specific support to help them transition and succeed in college.

Oral medication with activity specifically at the inflamed sites throughout the gastrointestinal tract and limited systemic exposure would be a major advance in our therapeutic approach to inflammatory bowel disease (IBD). For this purpose, we have designed a prodrug by linking active drug moiety to phospholipid (PL), the substrate of phospholipase A

Therapeutics with activity specifically at the inflamed sites throughout the gastrointestinal tract (GIT) would be a major advance in our therapeutic approach to inflammatory bowel disease (IBD). We aimed to develop the prodrug approach that can allow such site-specific drug delivery. Currently, using cyclosporine as a drug of choice in IBD is limited to the most severe cases due to substantial systemic toxicities and narrow therapeutic index of this drug. Previously, we synthesized a series of a phospholipid-linker-cyclosporine (PLC) prodrugs designed to exploit the overexpression of phospholipase A

Purpose This study seeks to identify the characteristics and attitudes of faculty in US medical colleges who are at risk of leaving their institution. Methods This research leverages data from the AAMC StandPoint Faculty Engagement Survey administered to 37,779 faculty representing 36 institutions participating during 2013-2016. Univariate and multivariable robust logistic regression models were used to assess predictors of the intent to leave based on the question: "Do you plan to leave this medical school in the next 1-2 years?". Results Thirty percent (n=5559/18,475) of faculty responded that they were considering leaving their institution. Thirty-one percent of female faculty vs 29% of male faculty expressed an intent to leave. At-risk faculty were likely to be at junior faculty rank and at their institutions for 6-15 years vs other time periods (OR=1.16; p≤0.001). Having an administrative title (OR=0.72; p≤0.001) and receiving formal mentorship (OR=0.65; p≤0.001) were protective. Finally, faculty answering "disagree" or "strongly disagree" to any one of these StandPoint Survey questions were at > 6 fold risk of expressing an intent to leave: 1) I am satisfied with my opportunities for professional development, 2) I feel appreciated by my supervisor, 3) My day-to-day activities give me a sense of accomplishment. Conclusion Faculty expressing an intent to leave their institution have an identifiable profile. Top concerns of at-risk faculty relate to supervisory relationships and growth opportunities rather than compensation or governance. Institutional leaders should consider these factors in the development of a proactive strategy to retain talented faculty.

Purpose A multiphasic cine sequence performed during magnetic resonance enterography (MRE) has been shown to increase diagnostic accuracy of MRE demonstrating limited movement in inflamed intestine in patients with Crohn’s disease (CD). Our aim was to confirm in our study population that intestinal inflammation was associated with decreased motility and determine if factors suggestive of complicated disease such as the presence of a stricture or fistula were associated with decreased motility on the MRE cine sequence. Methods This was a retrospective study of 59 patients (mean age 40.8 ± 16.1) with Crohn’s disease who had a small bowel lesion on MRE. Two gastrointestinal radiologists independently scored MRE findings using a qualitative, subjective scoring system. Univariate and multivariable ordered logistic regression models were used to evaluate the associations between cine sequence score, radiologic image findings, and clinical data. Results On univariate analysis, radiologic findings reflecting active inflammation, the presence of a stricture, and penetrating disease were associated with decreased motility. On multivariable analysis, hyper-enhancement, the presence of a comb sign, and global evidence of active inflammation remained associated with decreased motility. Of the factors suggesting complicated disease, the presence of stricture (Odds Ratio 0.40, 95% Confidence Interval 0.17-0.95, p-value 0.038) was associated with decreased motility. Conclusions As previously shown, well-established radiologic findings of bowel inflammation were associated with decreased small bowel motility. In this study, we have added that the radiologic finding of a fixed stricture is also associated with decreased motility.

The aim of this work is to analyze relevant endogenous lipid processing pathways, in the context of the impact that lipids have on drug absorption, their therapeutic use, and utilization in drug delivery. Lipids may serve as biomarkers of some diseases, but they can also provide endogenous therapeutic effects for certain pathological conditions. Current uses and possible clinical benefits of various lipids (fatty acids, steroids, triglycerides, and phospholipids) in cancer, infectious, inflammatory, and neurodegenerative diseases are presented. Lipids can also be conjugated to a drug molecule, accomplishing numerous potential benefits, one being the improved treatment effect, due to joined influence of the lipid carrier and the drug moiety. In addition, such conjugates have increased lipophilicity relative to the parent drug. This leads to improved drug pharmacokinetics and bioavailability, the ability to join endogenous lipid pathways and achieve drug targeting to the lymphatics, inflamed tissues in certain autoimmune diseases, or enable overcoming different barriers in the body. Altogether, novel mechanisms of the lipid role in diseases are constantly discovered, and new ways to exploit these mechanisms for the optimal drug design that would advance different drug delivery/therapy aspects are continuously emerging.

Oral medication with activity specifically at the inflamed sites throughout the gastrointestinal tract and limited systemic exposure would be a major advance in our therapeutic approach to inflammatory bowel disease (IBD). For this purpose, we have designed a prodrug by linking active drug moiety to phospholipid (PL), the substrate of phospholipase A2 (PLA2). PLA2 expression and activity is significantly elevated in the inflamed intestinal tissues of IBD patients. Since PLA2 enzyme specifically hydrolyses the sn-2 bond within PLs, in our PL-based prodrug approach, the sn-2 positioned FA is replaced with cyclosporine, so that PLA2 may be exploited as the prodrug-activating enzyme, releasing the free drug from the PL-complex. Owing to the enzyme overexpression, this may effectively target free cyclosporine to the sites of inflammation. Four PL-cyclosporine prodrugs were synthesized, differing by their linker length between the PL and the drug moiety. To study the prodrug activation, a novel enzymatically enriched model was developed, the colonic brush border membrane vesicles (cBBMVs); in this model, tissue vesicles were produced from colitis-induced (vs. healthy) rat colons. PLA2 overexpression (3.4-fold) was demonstrated in diseased vs. healthy cBBMVs. Indeed, while healthy cBBMVs induced only marginal activation, substantial prodrug activation was evident by colitis-derived cBBMVs. Together with the PLA2 overexpression, these data validate our drug targeting strategy. In the diseased cBBMVs, quick and complete activation of the entire dose was obtained for the 12-carbon linker prodrug, while slow and marginal activation was obtained for the 6/8-carbon linkers. The potential to target the actual sites of inflammation and treat any localizations throughout the GIT, together with the extended therapeutic index, makes this orally delivered prodrug approach an exciting new therapeutic strategy for IBD treatment.

Patients with inflammatory bowel disease (IBD) commonly require surgery despite the availability of an increasingly large repertoire of powerful immunosuppressive medications for the treatment of IBD. Optimizing patients’ care preoperatively is crucial to obtaining good surgical outcomes. This review discusses preoperative assessment and management principles including assessing disease location and activity with cross-sectional or endoscopic imaging, addressing modifiable risk factors (i.e., stopping smoking, weaning steroids, and correcting anemia), and properly managing medications. The major focus of our literature review is the evaluation for malnutrition, a common finding that affects up to 70% of patients with IBD and a well-known, independent risk factor for adverse postoperative outcomes. Our review confirms that whenever feasible, oral or enteral nutrition (EN) is the preferred method of nutritional support; parenteral nutrition (PN) should be reserved for nutritionally deficient IBD patients unable to tolerate EN. In selected patients, recent data demonstrated that the use of preoperative PN resulted in improved nutritional status, fewer postoperative complications, and reduced disease severity. Our review highlights the need for well-designed, prospective trials investigating perioperative nutritional support in patients with IBD. Future studies should perform modern nutritional assessment, standardize for diet, and include patients with UC since this subset of patients is underrepresented in existing studies. In addition, relevant outcome of interest specific to Crohn’s disease (CD) patients such as length of small bowel resected, number of anastomoses, and need for an ostomy should be included as these patients may require repeated small bowel resections.

Although the effects of biologic agents on postoperative outcomes in Crohn's disease patients have been extensively studied, the effects on intraoperative outcomes, including blood loss, operative time, and length of small bowel resection, remain to be determined. This was a retrospective cohort study at a single tertiary referral center. Crohn's disease (CD) patients who underwent major abdominal surgery were identified. Patients receiving preoperative biologic agents were compared with controls. We compare operative outcomes between groups. A total of 144 patients who underwent major abdominal surgery at the University of Florida between March 2007 and March 2017 were included. One hundred and ten patients (76%) who received pre-operative biologic therapy were compared with 34 controls. On univariate analysis, preoperative biologic use was associated with a significantly shorter length of small bowel resection (21.2 cm in biologic group vs 34.5 cm, P = 0.01). There were no significant differences in intraoperative blood loss (100 vs 87.5 mL, P = 0.40) or total operative time (142 vs 154 minutes, P = 0.39) between groups. On multivariate analysis controlling for variables reflecting severity of disease and malnutrition, biologic use remained significantly associated with shorter length of bowel resection (incident rate ratio 0.58, P = 0.04). Preoperative biologic use is associated with a significantly shorter length of bowel resection in CD patients undergoing major abdominal surgery. No negative effects were noted on operative blood loss or total operative time. Our findings allow improved preoperative planning for surgeons and informed decision-making for CD patients undergoing major abdominal surgery.

Computed tomography and magnetic resonance enterography have become routine small bowel imaging tests to evaluate patients with established or suspected Crohn's disease, but the interpretation and use of these imaging modalities can vary widely. A shared understanding of imaging findings, nomenclature, and utilization will improve the utility of these imaging techniques to guide treatment options, as well as assess for treatment response and complications. Representatives from the Society of Abdominal Radiology Crohn's Disease-Focused Panel, the Society of Pediatric Radiology, the American Gastroenterological Association, and other experts, systematically evaluated evidence for imaging findings associated with small bowel Crohn's disease enteric inflammation and established recommendations for the evaluation, interpretation, and use of computed tomography and magnetic resonance enterography in small bowel Crohn's disease. This work makes recommendations for imaging findings that indicate small bowel Crohn's disease, how inflammatory small bowel Crohn's disease and its complications should be described, elucidates potential extra-enteric findings that may be seen at imaging, and recommends that cross-sectional enterography should be performed at diagnosis of Crohn's disease and considered for small bowel Crohn's disease monitoring paradigms. A useful morphologic construct describing how imaging findings evolve with disease progression and response is described, and standard impressions for radiologic reports that convey meaningful information to gastroenterologists and surgeons are presented.

Targeting drugs to the inflamed intestinal tissue(s) represents a major advancement in the treatment of inflammatory bowel disease (IBD). In this work we present a powerful in-silico modeling approach to guide the molecular design of novel prodrugs targeting the enzyme PLA2, which is overexpressed in the inflamed tissues of IBD patients. The prodrug consists of the drug moiety bound to the sn-2 position of phospholipid (PL) through a carbonic linker, aiming to allow PLA2 to release the free drug. The linker length dictates the affinity of the PL-drug conjugate to PLA2, and the optimal linker will enable maximal PLA2-mediated activation. Thermodynamic integration and Weighted Histogram Analysis Method (WHAM)/Umbrella Sampling method were used to compute the changes in PLA2 transition state binding free energy of the prodrug molecule (∆∆Gtr) associated with decreasing/increasing linker length. The simulations revealed that 6-carbons linker is the optimal one, whereas shorter or longer linkers resulted in decreased PLA2-mediated activation. These in-silico results were shown to be in excellent correlation with experimental in-vitro data. Overall, this modern computational approach enables optimization of the molecular design of novel prodrugs, which may allow targeting the free drug specifically to the diseased intestinal tissue of IBD patients.

The purpose of the article is to compare information regarding small bowel lesions in Crohn’s disease (CD) patients communicated by a published scoring system and radiology reports from electronic medical record (EMR) of cross-sectional abdominal imaging. Two gastrointestinal radiologists (reference readers) blinded to EMR reports scored cross-sectional imaging exams using a published scoring system. Investigators compared EMR and radiologist scores based on the mentioned findings and severity documentation of each variable. Statistical analysis involved means and difference in proportions and logistic regression modeling. Seventy-three CD patients, with average age 40.6 years (± SD 14.4), having 80 small bowel lesions on imaging were included. EMR reports reliably mentioned within the consensus score included thickness (79%, p = 0.000), enhancement (70%, p = 0.000), active inflammation (86%, p = 0.000), perienteric fluid (82%, p = 0.000), and presence of stricture (62%, p = 0.002). Minimal lumen diameter (19%, p = 0.000), comb sign (19%, p = 0.000), lesion length (57%, p = 0.06), and fistula (50%, p = 1.0) were reported less often. There was a strong association between the EMR and scoring scale in noting severity of active inflammation (88%, p = 0.000), perienteric fluid (76%, p = 0.000), and internal fistula (71%, p = 0.000). The proportion matching severity values of comb sign and minimal lumen were 24% and 21%, respectively (p = 0.000). Severity matches for stricture were less likely among the non-GI radiologists (odds ratio = 0.33, SE = 0.168, p = 0.029). The odds of reporting stricture and fistula severity were 3.6 and 5.7, respectively, on MRE. Findings and severity of inflammation were communicated consistently. Stricture severity including minimal luminal diameter, was less reliably reported, though its prognostic significance impacts management.

The enzyme phospholipase A2 (PLA2) is overexpressed in the inflamed intestine in inflammatory bowel disease (IBD) patients, and in this work we aimed to exploit PLA2 as a prodrug-activating enzyme for a novel PL-drug conjugate, thereby liberating the free drug specifically in the targeted diseased tissue(s). The proposed prodrug contains a drug moiety covalently bound through a linker to the sn-2 position of a phospholipid (PL). The NSAID diclofenac was used as model molecule, and four different linker lengths (2, 4, 6 and 8 -CH2 units) were studied. The four PL-diclofenac conjugates were synthesized and characterized by LC/MS and NMR. PLA2-mediated activation of the prodrugs was analyzed in-vitro, and the remaining intact complex and free drug liberation were assessed after incubation with PLA2. The rate and degree of PLA2-mediated activation were highly dependent on the linker length; 2- and 4-carbon linker conjugates were activated to lower extent than the 6-carbon conjugate, and longer linker again decreased the affinity towards PLA2. The 6-carbon linker conjugate was found to be the optimal and released ~95% of the free drug after incubation with PLA2, whereas only ~20% were delivered by the 2-carbon linker prodrug. The 6-carbon linker conjugate was shown to be stable in intestinal perfusate, fresh plasma, and pH4.0 and 6.8 buffers, but not at pH1.0. In conclusion, the results of this work confirm the feasibility of our general aim to exploit PLA2 as a prodrug-activating enzyme of PL-drug conjugates. This may provide a novel oral drug targeting approach in IBD therapy.

Nowadays, prodrugs are no longer used as a last resort, rather, they are intentionally designed at the early stages of drug development. Lipidic prodrug strategy, where a drug moiety is covalently bound to a lipid carrier, was initially proposed half a century ago, yet, this approach still remains to be explored. Lipidic prodrugs can join physiological lipid metabolic pathways, and hence provide drug targeting via lymphatic transport or site-specific drug release, improve drugs’ pharmacokinetic profile, overcome obstacles originating from biological barriers and bypass hepatic first-pass metabolism. Physiological pathways of lipid processing, uses of different lipidic prodrugs and their clinical benefits are overviewed. Overall, lipidic prodrugs present a promising approach for overcoming different obstacles and fulfilling various unmet needs in drug delivery/targeting.

The lipidic prodrug approach is an emerging field for improving a number of biopharmaceutical and drug delivery aspects. Owing to their structure and nature, phospholipid (PL)-based prodrugs may join endogenous lipid processing pathways, and hence significantly improve the pharmacokinetics and/or bioavailability of the drug. Additional advantages of this approach include drug targeting by enzyme-triggered drug release, blood&ndash, brain barrier permeability, lymphatic targeting, overcoming drug resistance, or enabling appropriate formulation. The PL-prodrug design includes various structural modalities-different conjugation strategies and/or the use of linkers between the PL and the drug moiety, which considerably influence the prodrug characteristics and the consequent effects. In this article, we describe how molecular modeling can guide the structural design of PL-based prodrugs. Computational simulations can predict the extent of phospholipase A2 (PLA2)-mediated activation, and facilitate prodrug development. Several computational methods have been used to facilitate the design of the pro-drugs, which will be reviewed here, including molecular docking, the free energy perturbation method, molecular dynamics simulations, and free density functional theory. Altogether, the studies described in this article indicate that computational simulation-guided PL-based prodrug molecular design correlates well with the experimental results, allowing for more mechanistic and less empirical development. In the future, the use of molecular modeling techniques to predict the activity of PL-prodrugs should be used earlier in the development process.

In ulcerative colitis (UC), the inflammation is localized in the colon, and one of the successful strategies for colon-targeting drug delivery is the prodrug approach. In this work, we present a novel phospholipid (PL)-based prodrug approach, as a tool for colonic drug targeting in UC. We aim to use the phospholipase A2 (PLA2), an enzyme that is overexpressed in the inflamed colonic tissues of UC patients, as the PL-prodrug activating enzyme, to accomplish the liberation of the parent drug from the prodrug complex at the specific diseased tissue(s). Different linker lengths between the PL and the drug moiety can dictate the rate of activation by PLA2, and subsequently determine the amount of free drugs at the site of action. The feasibility of this approach was studied with newly synthesized PL-Fmoc (fluorenylmethyloxycarbonyl) conjugates, using Fmoc as a model compound for testing our hypothesis. In vitro incubation with bee venom PLA2 demonstrated that a 7-carbon linker between the PL and Fmoc has higher activation rate than a 5-carbon linker. 4-fold higher colonic expression of PLA2 was demonstrated in colonic mucosa of colitis-induced rats when compared to healthy animals, validating our hypothesis of a colitis-targeting prodrug approach. Next, a novel molecular dynamics (MD) simulation was developed for PL-based prodrugs containing clinically relevant drugs. PL-methotrexate conjugate with 6-carbon linker showed the highest extent of PLA2-mediated activation, whereas shorter linkers were activated to a lower extent. In conclusion, this work demonstrates that for carefully designed PL-drug conjugates, PLA2 overexpression in inflamed colonic tissues can be used as prodrug-activating enzyme and drug targeting strategy, including insights into the activation mechanisms in a PLA2 binding site.

Inflammatory bowel disease (IBD) is characterized by gastrointestinal inflammation comprised of Crohn’s disease and ulcerative colitis. Centers for Disease Control and Prevention report that 1.3% of the population of the United States (approximately 3 million people) were affected by the disease in 2015, and the number keeps increasing over time. IBD has a multifactorial etiology, from genetic to environmental factors. Most of the IBD treatments revolve around disease management, by reducing the inflammatory signals. We previously identified the surface layer protein A (SlpA) of Lactobacillus acidophilus that possesses anti-inflammatory properties to mitigate murine colitis. Herein, we expressed SlpA in a clinically relevant, food-grade Lactococcus lactis to further investigate and characterize the protective mechanisms of the actions of SlpA. Oral administration of SlpA-expressing L. lactis (R110) mitigated the symptoms of murine colitis. Oral delivery of R110 resulted in a higher expression of IL-27 by myeloid cells, with a synchronous increase in IL-10 and cMAF in T cells. Consistent with murine studies, human dendritic cells exposed to R110 showed exquisite differential gene regulation, including IL-27 transcription, suggesting a shared mechanism between the two species, hence positioning R110 as potentially effective at treating colitis in humans.

In inflammatory bowel disease (IBD) patients, the enzyme phospholipase A2 (PLA2) is overexpressed in the inflamed intestinal tissue, and hence may be exploited as a prodrug-activating enzyme allowing drug targeting to the site(s) of gut inflammation. The purpose of this work was to develop powerful modern computational approaches, to allow optimized a-priori design of phospholipid (PL) based prodrugs for IBD drug targeting. We performed simulations that predict the activation of PL-drug conjugates by PLA2 with both human and bee venom PLA2. The calculated results correlated well with in-vitro experimental data. In conclusion, a-priori drug design using a computational approach complements and extends experimentally derived data, and may improve resource utilization and speed drug development.

A new era of Crohn’s disease management exists where decisions are made by objective data as a necessary adjunct to patient symptoms. Cross-sectional imaging, particularly CT enterography (CTE) and MR enterography (MRE), provides powerful objective insights into the disease process resulting in a firm place for cross-sectional imaging in our current diagnostic and management paradigms. The high sensitivity and specificity of the techniques for the presence of bowel inflammation have helped pinpoint the location and severity of disease enabling diagnosis and facilitating assessment of symptoms. The ability to identify disease complications has helped direct medical therapy and enables more robust presurgical assessment. Emerging data suggest that cross-sectional imaging findings are sensitive to changes in inflammation resulting from our potent biologic therapies and may be used in amazing new ways such as in predicting disease course. Technological advances in CT and MR enterography have provided new insights into the disease processes while enhancing patient safety and tolerability. The goal of this chapter is to provide a gastroenterologist’s view of how cross-sectional imaging fits our current and future management algorithm. These remarkable technologies enable gastroenterologists and radiologists, working together, to serve our patient population in profound ways.

Although the effects of biologic agents on postoperative outcomes in Crohn's disease patients have been extensively studied, the effects on intraoperative outcomes, including blood loss, operative time, and length of small bowel resection, remain to be determined. This was a retrospective cohort study at a single tertiary referral center. Crohn's disease (CD) patients who underwent major abdominal surgery were identified. Patients receiving preoperative biologic agents were compared with controls. We compare operative outcomes between groups. A total of 144 patients who underwent major abdominal surgery at the University of Florida between March 2007 and March 2017 were included. One hundred and ten patients (76%) who received preoperative biologic therapy were compared with 34 controls. On univariate analysis, preoperative biologic use was associated with a significantly shorter length of small bowel resection (21.2 cm in biologic group

In the past, a prodrug design was used as a last option to improve bioavailability through controlling transport, distribution, metabolism, or other mechanisms. Prodrugs are currently used even in early stages of drug development, and a significant percentage of all drugs in the market are prodrugs. The focus of this article is lipidic prodrugs, a strategy whereby a lipid carrier is covalently bound to the drug moiety. The increased lipophilicity of the lipid-drug conjugate can improve the pharmacokinetic profile and provide meaningful advantages: increased absorption across biological barriers, prolonged circulation half-life, selective distribution profile (eg brain penetration), reduced hepatic first-pass metabolism, and overall enhanced bioavailability of the parent drug. Moreover, lipidic prodrugs may join the endogenous lipid trafficking pathways, thereby facilitate drug targeting, either by selective absorption pathway (eg lymphatic transport) or drug release at specific target site(s). The different lipid-drug conjugates (triglyceride-, fatty acids, phospholipid-, and steroid-based prodrugs), the physiological barriers that challenge the absorption of these conjugates, followed by their current utilization and potential clinical benefits are described and analyzed, and future opportunities this approach could provide are discussed. Altogether, lipidic prodrugs represent an exciting approach for improving different aspects of oral drug delivery/therapy and may provide solutions for various unmet needs; the use of this strategy is expected to grow.

Robert Hromas,1 Robert Leverence,1 Lazarus K Mramba,2 J Larry Jameson,3 Caryn Lerman,3 Thomas L Schwenk,4 Ellen M Zimmermann,2 Michael L Good51The Office of the Dean, Department of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA; 2Department of Medicine, College of Medicine, University of Florida Health, Gainesville, FL, USA; 3Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA; 4Department of Family Medicine, School of Medicine, University of Nevada Reno, Reno, NV, USA; 5Department of Anesthesiology, College of Medicine, University of Florida Health, Gainesville, FL, USAAbstract: Economic pressure has led the evolution of the role of the medical school dean from a clinician educator to a health care system executive. In addition, other dynamic requirements also have likely led to changes in their leadership characteristics. The most important relationship a dean has is with the chairs, yet in the context of the dean’s changing role, little attention has been paid to this relationship. To frame this discussion, we asked medical school chairs what characteristics of a dean’s leadership were most beneficial. We distributed a 26-question survey to 885 clinical and basic science chairs at 41 medical schools. These chairs were confidentially surveyed on their views of six leadership areas: evaluation, barriers to productivity, communication, accountability, crisis management, and organizational values. Of the 491 chairs who responded (response rate =55%), 88% thought that their dean was effective at leading the organization, and 89% enjoyed working with their dean. Chairs indicated that the most important area of expertise of a dean is to define a strategic vision, and the most important value for a dean is integrity between words and deeds. Explaining the reasons behind decisions, providing good feedback, admitting errors, open discussion of complex or awkward topics, and skill in improving relations with the teaching hospital were judged as desirable attributes of a dean. Interestingly, only 23% of chairs want to be a dean in the future. Financial acumen was the least important skill a chair thought a dean should hold, which is in contrast to the skill set for which many deans are hired and evaluated. After reviewing the literature and analyzing these responses, we assert that medical school chairs want their dean to maintain more traditional leadership than that needed by a health care system executive, such as articulating a vision for the future and keeping their promises. Thus, there appears to be a mismatch between what medical school chairs perceive they need from their dean and how the success of a dean is evaluated. Keywords: academic medicine deans, leadership characteristics, organizational values

Background Despite major advances in the medical management of Crohn’s disease (CD), a significant proportion of patients will require surgery within 5 years of diagnosis. Malnutrition is an independent risk factor for adverse post-operative outcomes following gastrointestinal surgery. Data on the value of pre-operative total parenteral nutrition (TPN) in CD patients are mixed and there is a paucity of data in the biologic era. We aimed to define the role of pre-operative TPN in this population. Methods This was a retrospective cohort study conducted at a tertiary referral center. CD patients who underwent major abdominal surgery were identified. Patients receiving pre-operative TPN were compared to controls. We compared the incidence of 30-day infectious and non-infectious post-operative complications between the two groups. Results A total of 144 CD patients who underwent major abdominal surgery between March 2007 and March 2017 were included. Fifty-five patients who received pre-operative TPN were compared to 89 controls. Twenty-one (14.6%) patients developed infectious complications (18.2% in TPN group vs 12.3% in non-TPN group, P = 0.34) and 23 (15.9%) developed non-infectious complications (14.5% in TPN group vs 16.9% in non-TPN group, P = 0.71). In a multivariate analysis, controlling for differences in baseline disease severity and malnutrition between groups, patients receiving pre-operative TPN for ≥60 days had significantly lower odds of developing non-infectious complications (odds ratio 0.07, 95% confidence interval: 0.01–0.80, P = 0.03). Weight loss of >10% in the past 6 months was a significant predictor of post-operative complications. Conclusions In a subset of malnourished CD patients, TPN is safe and allows comparable operative outcomes to controls. Pre-operative TPN for ≥60 days reduced post-operative non-infectious complications without associated increase in infectious complications.

Background and aims Medication persistence, defined as the time from drug initiation to discontinuation of therapy, has been suggested as a proxy for real-world therapeutic benefit and safety. This study seeks to compare the persistence of biologic drugs among patients with inflammatory bowel disease (IBD). Methods Patients with newly diagnosed IBD were included in a retrospective study using Truven MarketScan database. Treatment persistence and switching was compared among biologic medications including infliximab, adalimumab, certolizumab, golimumab, and vedolizumab. Predictors for discontinuation and switching were evaluated using time-dependent proportional hazard regression. Results In total, 5612 patients with Crohn’s disease (CD) and 3533 patients with ulcerative colitis (UC) were included in this analysis. Less than half of the patients continued using their initial biologic treatment after 1 year (48.48% in CD cohort; 44.78% in UC cohort). In the first year, adalimumab had the highest persistence and lowest switching rates for both CD (median survival time: 1.04 years) and UC (median survival time: 0.84 years). In subsequent years, infliximab users were more likely to persist in the use of biologic. Combination therapy with immunomodulators significantly decreased the risk of discontinuation, especially when immunomodulator therapy was started more than 30 days before the biologic (hazard ratio [HR], 0.22; CI, 0.16, 0.32). The major predictors for noncompliance included infection and hospitalization. Conclusion Overall, the persistence profiles of biologics suggest a high rate of dissatisfaction or adverse disease outcomes resulting in discontinuation and switching to a different agent. Early initiation of immunomodulators will substantially increase the persistence of biologic treatment.

Computed tomography and magnetic resonance enterography have become routine small bowel imaging tests to evaluate patients with established or suspected Crohn's disease, but the interpretation and use of these imaging modalities can vary widely. A shared understanding of imaging findings, nomenclature, and utilization will improve the utility of these imaging techniques to guide treatment options, as well as assess for treatment response and complications. Representatives from the Society of Abdominal Radiology Crohn's Disease-Focused Panel, the Society of Pediatric Radiology, the American Gastroenterological Association, and other experts, systematically evaluated evidence for imaging findings associated with small bowel Crohn's disease enteric inflammation and established recommendations for the evaluation, interpretation, and use of computed tomography and magnetic resonance enterography in small bowel Crohn's disease. This work makes recommendations for imaging findings that indicate small bowel Crohn's disease, how inflammatory small bowel Crohn's disease and its complications should be described, elucidates potential extra-enteric findings that may be seen at imaging, and recommends that cross-sectional enterography should be performed at diagnosis of Crohn's disease and considered for small bowel Crohn's disease monitoring paradigms. A useful morphologic construct describing how imaging findings evolve with disease progression and response is described, and standard impressions for radiologic reports that convey meaningful information to gastroenterologists and surgeons are presented.

Background Patients with Crohn's disease (CD) typically undergo multiple cross-sectional imaging exams including computed tomography and magnetic resonance enterography during the course of their disease. The aim was to identify imaging findings that predict future disease-related poor outcomes. Methods This was a retrospective, case control study at a single tertiary center. Cases were CD patients diagnosed with complications (bowel obstruction, perforation, internal fistula, or abscess); controls were CD patients without complications. Two radiologists blinded to clinical outcomes, independently scored cross-sectional imaging examinations obtained before the complication. Results One hundred eight patients (67 F; 41 M) with CD (51 cases; 57 controls) were included. For the cases, 21 had internal fistulae, 15 had bowel obstructions, 13 had abdominal abscesses, and 2 developed bowel perforations. Patients with complications were more likely to have a fixed small bowel stricture on cross-sectional imaging (P = 0.01). A patient with a stricture and upstream dilatation was 3.4 times more likely to develop a complication in the next 2 years. When present in the setting of hypervascularity and/or evidence of active inflammation, the risk increased further to 15-fold. Cases were more likely to be active smokers (29% versus 12%, P = 0.033). Cases had more evidence of inflammation based on higher Harvey Bradshaw Index values and inflammatory biomarkers and lower hemoglobin values. Conclusions Information from radiologic studies, especially the presence of fixed strictures, can predict future CD complications. These findings, along with smoking and ongoing inflammation, should alert the clinician to the possibility of future complications.

The molecular information that became available over the past two decades significantly influenced the field of drug design and delivery at large, and the prodrug approach in particular. While the traditional prodrug approach was aimed at altering various physiochemical parameters, e.g., lipophilicity and charge state, the modern approach to prodrug design considers molecular/cellular factors, e.g., membrane influx/efflux transporters and cellular protein expression and distribution. This novel targeted-prodrug approach is aimed to exploit carrier-mediated transport for enhanced intestinal permeability, as well as specific enzymes to promote activation of the prodrug and liberation of the free parent drug. The purpose of this article is to provide a concise overview of this modern prodrug approach, with useful successful examples for its utilization. In the past the prodrug approach used to be viewed as a last option strategy, after all other possible solutions were exhausted; nowadays this is no longer the case, and in fact, the prodrug approach should be considered already in the very earliest development stages. Indeed, the prodrug approach becomes more and more popular and successful. A mechanistic prodrug design that aims to allow intestinal permeability by specific transporters, as well as activation by specific enzymes, may greatly improve the prodrug efficiency, and allow for novel oral treatment options.

Purpose This study examines the relationship between quantitative magnetization transfer (qMT) parameters and the molecular composition of a model lamellar liquid crystal (LLC) system composed of 1-decyl alcohol (decanol), sodium dodecyl sulfate (SDS), and water. Methods Samples were made within a stable lamellar mesophase to provide different ratios of total semisolid protons (SDS + decanol) to water protons. Data were collected as a function of radiofrequency power, frequency offset, and temperature. qMT parameters were estimated by fitting a standard model to the data. Fitting results of four different semisolid line shapes were compared. Results A super-Lorentzian line shape for the semisolid component provided the best fit. The estimated amount of semisolids was proportional to the ratio of decanol-to-water protons. Other qMT parameters exhibited nonlinear dependence on sample composition. Magnetization transfer ratio (MTR) was a linear function of the semisolid fraction over a limited range of decanol concentration. Conclusion In LLC samples, MT between semisolid and water originates from intramolecular nOe among decanol aliphatic chain protons followed by proton exchange between decanol hydroxyl and water. Exchange kinetics is influenced by SDS, although SDS protons do not participate in MT. These studies provide clinically relevant range of semisolid fraction proportional to detected MTR. Magn Reson Med 72:1427–1434, 2014. © 2013 Wiley Periodicals, Inc.