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Jencks, Kara J.

https://orcid.org/0000-0002-4248-5291

Mayo Clinic

Mayo Clinic

Citations 17

Clinical Trial: Multi‐Strain Probiotic Improves Bile Acid Profile, Microbiome, and Metabolomic Parameters in Patients With History of Bile Acid Malabsorption—A Randomized, Controlled Trial
Matar, Ayah , Carlson, Paula, Busciglio, Irene, Johnson, Stephen, Mars, Ruben A., Kashyap, Purna C., Harmsen, W.S., Camilleri, Michael , Damianos, John A , Matar, Ayah , Jencks, Kara J. , Camilleri, M , Damianos, John , Busciglio, Irene, Johnson, Stephen, Mars, Ruben A. , Kashyap, Purna

Alimentary Pharmacology & Therapeutics | July 23, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1111/apt.70876 Get It

ABSTRACT Background Bile acid (BA) malabsorption (BAM) is a common cause of chronic diarrhoea and may occur in some patients due to abnormalities of the gut microbiota. Effects of probiotics on faecal secretory BAs, particularly the primary BA, chenodeoxycholic acid, are unclear. Aim/Methods We conducted a randomized, double‐blind, placebo‐controlled trial of the De Simone formulation 8‐strain probiotic in 24 patients previously diagnosed with BAM. Patients were randomized to 3 weeks of the probiotic (900 billion bacteria) or placebo (maltose), both administered three times daily. Symptoms, serum 7 α C4, faecal primary BAs, intestinal permeability by 13 C‐mannitol‐lactulose test (0.1 and 1 g of the sugars respectively) over 24 h, faecal short chain fatty acids (SCFA), microbiome, and metabolome were assessed at baseline and post‐intervention. Results Data from 22 patients were included. Probiotic supplementation was associated with a significant decrease in % faecal primary BAs (chenodeoxycholic acid and cholic acid) with median change from baseline −5.7 [IQR −10.3, 0.9]% compared to 9.8 [IQR 0.2, 20.6]% on placebo ( p = 0.012). The faecal microbiome was significantly different in the probiotic group after intervention, driven by probiotic‐specific species. There were no significant differences in symptoms, intestinal permeability, or SCFA. However, there was a numerical difference in the changes from baseline in 0‐2 h 13 C‐mannitol excretion −1.9 [−13.9, 4.2] mg for the probiotic and 1.0 (−0.5, 12.7) mg for placebo ( p = 0.084). Conclusions The De Simone formulation probiotic induced significant microbiome and metabolome changes in patients with BAM, ultimately leading to a decrease in % faecal primary BAs and possible reduction in intestinal permeability. Clinical Trials.gov registration NCT #06609148, January 2, 2025.
Recognizing Suspected Colonic Hypercompliance in Refractory Constipation When Barostat Testing Is Unavailable—Authors' Reply
Camilleri, Michael , Jencks, Kara J. , Camilleri, M

Neurogastroenterology & Motility | July 6, 2026 | Volume: 38 | Issue: 7 | Pages: No page available

10.1111/nmo.70388 Get It

Medically Refractory Constipation With Colonic Hypercompliance: Comparison With Megacolon and Healthy Colon
Matar, Ayah , Burton, D D, Beyder, Arthur, Bharucha, Adil E. , Camilleri, Michael , Jencks, Kara J. , Matar, Ayah , Burton, Duane, Camilleri, M , Beyder, Arthur

Neurogastroenterology & Motility | April 24, 2026 | Volume: 38 | Issue: 4 | Pages: No page available

10.1111/nmo.70327 Get It

ABSTRACT Background Chronic megacolon is an uncommon neurogastrointestinal disorder typically characterized by a persistent increase in colonic diameter. Methods Our aim was to identify adults with medical treatment‐refractory constipation without radiographic criteria for megacolon but with increased colonic compliance (refractory constipation with colonic hypercompliance (RCCH)), and to compare the colonic compliance in 7 identified patients with “RCCH” to colonic compliance in 10 patients with chronic megacolon by radiographic criteria (i.e., megacolon) and 40 healthy volunteers. After endoscopic placement, compliance of left or transverse colon was measured using a 10‐cm‐long infinitely compliant balloon connected to an electronically controlled rigid piston barostat. The barostat inflated the balloon from 0 to 44 mmHg in 4‐mmHg steps at 30‐s intervals to measure colonic compliance (pressure‐volume relationship). Eligibility criteria for inclusion were increased colonic compliance based on a functional assessment without meeting radiographic criteria for megacolon (i.e., RCCH). In the three groups, we compared colonic volumes at intra‐balloon pressure of 8, 16, 20, 32, and 44 mmHg, the pressure at half maximum volume, and the slope of the colonic compliance curve using ANOVA on ranks and Dunn's pairwise comparison test. Other features of colonic motility were documented. Results Colonic volumes at all pressures (8‐44 mmHg) and the pressure at half maximum volume were significantly greater in patients with megacolon and RCCH than in healthy controls ( p < 0.001 for both), but compliance was not significantly different between RCCH and megacolon. Conclusion A subset of patients with medically‐refractory chronic constipation has colonic compliance similar to that of patients with megacolon.
A Pilot Validation Study of Plant‐Based and Allergy‐Friendly Alternative for Testing Gastric Emptying: A Randomized Trial in Healthy Participants
Abdelnaem, Nada, Carlson, Paula, Busciglio, Irene, Burton, Duane, Ryks, Michael, Johnson, Derek R., Navin, Patrick J. , Bach, Corrie R. , Paulsen, Andrew, Bartlett, David J. , Camilleri, M., Jencks, Kara J. , Bach, Corrie, Paulsen, Andrew M, Camilleri, M , Navin, Patrick , Ryks, Michael, Johnson, Derek R., Camilleri, Michael

Neurogastroenterology & Motility | February 13, 2026 | Volume: 38 | Issue: 2 | Pages: No page available

10.1111/nmo.70268 Get It

ABSTRACT Background Gastric emptying (GE) scintigraphy with 4‐h imaging and a radiolabeled chicken egg‐based meal (320 kcal, 30% fat) is the standard test for gastroparesis at Mayo Clinic, with an intraindividual coefficient of variation (COV intra ) of 23.8% for GE half emptying time (T 1/2 ). Alternative meals for patients with dietary restrictions, including egg allergies or vegan diets, are lacking, limiting test accessibility. The study aimed to establish a vegan, lactose‐, nut‐, and gluten‐free meal with similar caloric and fat content to the egg meal and to assess its performance in GE studies. Methods In Vitro: 99m Tc binding to egg meal over 4 h was compared to a calorically and nutritionally similar vegan alternative, JUST Egg, using a validated in vitro model simulating gastric conditions of pH, pepsin, and stirring. In Vivo: 10 healthy participants underwent randomized crossover GE scintigraphy with standard and vegan meals, spaced ≥ 3 days apart to measure GE% at 2 h, 4 h, and GE T 1/2 . Group comparisons and variance analysis included Rank Sum tests and Bland–Altman plots. Key Results In Vitro: A strong correlation ( R = 0.975, p ‐value < 0.01) between 99m Tc binding in the egg and vegan egg models was observed. Minimal variance (< 10%) was recorded at all time points. In Vivo: GE at 4 h and GE T 1/2 showed non‐statistically significant mean differences, < 2% and < 10 min respectively, between both meals. The intra‐individual variability was 18.8%. Conclusions and Inferences The vegan meal demonstrated in vitro stability, in vivo performance comparable to the egg meal, and a COV intra of 18.8%, which was lower than the 23.8% reported in repeat egg meal GE studies. Trial Registration ClinicalTrials.gov number NCT06991036 ( https://clinicaltrials.gov/study/NCT06991036?term=NCT06991036&rank=1 )
A pilot, randomized, placebo-controlled trial of rimegepant on visceral sensation and symptoms in nonconstipation IBS pain
Halawi, Houssam, Matar, Ayah, Wang, Iris, Jencks, Kara J. , Busciglio, Irene, Eckert, Deborah J., Harmsen, William S., Camilleri, Michael, Wang, Xiao Jing , Matar, Ayah , Matar, Ayah , Wang, Xiao Jing , Eckert, Deborah, Camilleri, M , Jencks, Kara , Halawi, Houssam , Matar, Ayah , Harmsen, William S., Camilleri, Michael

American Journal of Physiology-Gastrointestinal and Liver Physiology | February 4, 2026 | Volume: 330 | Issue: 4 | Pages: G369-G380

10.1152/ajpgi.00394.2025 Get It

This pilot, randomized, double-blind trial in a relatively small sample of patients with IBS-related pain shows rimegepant significantly reduced sensations of gas, urgency, and pain during rectal distention and decreased rectal compliance. Decrease in compliance implies that changes in physical properties or distensibility of rectum did not contribute to alterations in rectal sensation. Same dose of rimegepant did not significantly impact daily abdominal pain, BM frequency, or colonic transit. There were no serious adverse events.
Correction to: Atypical Presentations of Levator Ani Syndrome With Perianal Hyperhidrosis: A Case Series
Gupta, Riya , Wang, Xiao Jing (Iris), Jencks, Kara J. , Damianos, John

ACG Case Reports Journal | January 5, 2026 | Volume: 13 | Issue: 1 | Pages: No page available

10.14309/crj.0000000000001948 Get It

Atypical Presentations of Levator Ani Syndrome With Perianal Hyperhidrosis: A Case Series
Gupta, Riya , Jencks, Kara J. , Wang, Xiao Jing (Iris), Jencks, Kara , Damianos, John , Wang, Xiao‐Jing

ACG Case Reports Journal | September 11, 2025 | Volume: 12 | Issue: 9 | Pages: No page available

10.14309/crj.0000000000001826 Get It

ABSTRACT Levator ani syndrome (LAS) explains up to 7.4% of anorectal pain cases. Classic symptoms include rectal pain or pressure with sitting. We present 2 patients, ages 32 and 25 years, presenting initially with “diarrhea” and perianal hyperhidrosis. History revealed rectal discomfort, tenesmus, urgency, and sensation of incomplete evacuation. Puborectalis tenderness was present on digital rectal examination. Therapies were tailored to each patient, including pelvic floor physical therapy with biofeedback, bowel regulation, rectal diazepam, and ileostomy. These presentations offer insights into potential pathophysiological mechanisms in LAS and highlight the importance of considering LAS in non-pain presentations.
Effects of Ricinoleic Acid (Castor Oil) on Gut Permeability in Healthy Participants: Provocative Test for Treatments Aimed at Restoring Barrier Function
Yang, David Yi , Lupianez‐Merly, Camille , Jencks, Kara J. , Busciglio, Irene, Eckert, Deborah J., Ryks, Michael, Dyer, Roy B. , Vizenor, Brady A., Zhao, Yuxi , Sapone, Anna, Rooks, Michelle, Gale, Jeremy D. , Camilleri, Michael , Dilmaghani, Saam , Eckert, Deborah, Dyer, Roy, Camilleri, M , Jencks, Kara , Vizenor, Brady A.

Clinical and Translational Gastroenterology | May 28, 2025 | Volume: 16 | Issue: 7 | Pages: e00865

10.14309/ctg.0000000000000865 Get It

INTRODUCTION: Altered intestinal permeability (IP) is implicated in multiple gastrointestinal and systemic disease conditions; an experimental model of perturbed IP in healthy subjects is needed. Traditional approaches to perturbing IP include use of nonsteroidal anti-inflammatory drugs. METHODS: We conducted a single-center, randomized, placebo-controlled pilot study of dose-related effects of castor oil (CO) (and its ingredient ricinoleic acid) at 750, 1,500, or 3,000 mg daily doses on IP. Permeability was assessed using validated 13 C-mannitol and lactulose urine excretion at 0–2, 8–24, and 0–24 hours after oral administration. RESULTS: Permeability analysis across all groups demonstrated significant difference among the groups for 0–2 hours 13 C-mannitol, 0–24 hours 13 C-mannitol, and borderline significant difference for 2–8 hours 13 C-mannitol ( P = 0.060) and 0–24 hours lactulose ( P = 0.056). Direct comparison of 3,000 mg CO vs placebo ( t test) demonstrated higher excretion of 13 C-mannitol and lactulose at 0–2, and 0–24 hours, and lactulose at 2–8 hours. DISCUSSION: CO may perturb small intestinal and colonic permeability in healthy adults.
S1193 Improvement in Disease-Related Biomarkers With an Adjuvant Treatment for 180 Days: Results From an Interventional Trial for Patients With Ulcerative Colitis
Turgeon, D. Kim , McClintock, Shannon D., Moraga, Gillian, Harber, Isabelle , McNeely, Molly M. , Varani, James, Aslam, Muhammad N. , Jencks, Kara J. , Stidham, Ryan W , Allen, Ron

American Journal of Gastroenterology | October 24, 2024 | Volume: 119 | Issue: 10S | Pages: S848-S848

10.14309/01.ajg.0001034140.69061.d8 Get It

S801 Dose-Related Effects of Ricinoleic Acid (Castor Oil) on Gut Permeability in Healthy Participants: Provocative Test for Treatments Aimed at Restoring Barrier Function
Lupianez‐Merly, Camille , Busciglio, Irene, Eckert, Deborah J., Ryks, Michael, Dyer, Roy B. , Vizenor, Brady A., Zhao, Yuxi , Sapone, Anna, Rooks, Michelle, Gale, Jeremy D. , Camilleri, Michael , Yang, David Yi , Jencks, Kara J. , Dilmaghani, Saam , Vizenor, Brady A.

American Journal of Gastroenterology | October 24, 2024 | Volume: 119 | Issue: 10S | Pages: S552-S553

10.14309/01.ajg.0001032572.47643.cf Get It