Mary H. Clench
University of Texas Medical Branch
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Digestive Diseases and Sciences | 1994
John R. Mathias; Mary H. Clench; Vonda G. Reeves-Darby; Lisa Mehelich Fox; Ping H. Hsu; Patricia H. Roberts; Lesa L. Smith; Norma J. Stiglich
Moderate to severe functional bowel disease results in debilitating abdominal pain, nausea, intermittent vomiting, early satiety, bloating, abdominal distension, and/or altered bowel habits. Because it occurs ∼20–30 times more frequently in women than in men and its symptoms often coincide with the menstrual cycle, we hypothesized that reproductive steroids may antagonize diseased nerves of the gastrointestinal tract, enhancing the expression of symptoms. No effective or consistent therapy has existed for these patients. We prospectively investigated the effect of a gonadotropin-releasing hormone analog, leuprolide acetate, in 30 women with symptoms of moderate to severe functional bowel disease. The study was phase II, randomized, double blind, and placebo controlled. Lupron Depot 3.75 mg (which delivers a continuous low dose of drug for one month) or placebo were given intramuscularly monthly for three months. Symptom scores were assessed at each four-week visit. Follicle-stimulating hormone, luteinizing hormone, estradiol, and progesterone levels were assessed before and after therapy. Patients treated with low-dose leuprolide improved progressively and significantly in scores for nausea, vomiting, bloating, abdominal pain, and early satiety, and for overall symptoms (P<0.01–0.05). All hormone levels decreased significantly (P<0.05) except luteinizing hormone (P=0.054).
Digestive Diseases and Sciences | 1998
John R. Mathias; Mary H. Clench; Thomas L. Abell; Kenneth L. Koch; Glen A. Lehman; Malcolm K. Robinson; Robin D. Rothstein; William J. Snape
We have previously reported impressive results in using a gonadotropin-releasing hormone analog, leuprolide acetate (Lupron), in the treatment of moderate to severe symptoms (especially abdominal pain and nausea) in patients with functional bowel disease (FBD). Pain is the hallmark of patients with FBD, and there is no consistent therapy for the treatment of these patients. The purpose of the present study was to expand the investigation to study similar patients (menstruating females) in a multicenter, double-blind, placebo-controlled, randomized study using Lupron Depot (which delivers a continuous dose of drug for one month), 3.75 mg (N = 32) or 7.5 mg (N = 33), or placebo (N = 35) given intramuscularly every four weeks for 16 weeks. Symptoms were assessed using daily diary cards to record abdominal pain, nausea, vomiting, early satiety, anorexia, bloating, and altered bowel habits. Additional assessment tools were quality of life questionnaires, psychological profile, oralto-cecal transit using the hydrogen breath test, antroduodenal manometry, reproductive hormone levels, and global evaluations by both patient and investigator. Patients in both Lupron Depot-treated groups showed consistent improvement in symptoms; however, only the Lupron Depot 7.5 mg group showed a significant improvement for abdominal pain and nausea compared to placebo (P < 0.001). Patient quality of life assessments and global evaluations completed by both patient and investigators were highly significant compared to placebo (P < 0.001). All reproductive hormone levels significantly decreased for both Lupron Depot-treated groups by week 4 and were significantly different compared to placebo at week 16 (P < 0.001). This study shows that leuprolide acetate is effective in controlling the debilitating symptoms of abdominal pain and nausea in patients with FBD.
Digestive Diseases and Sciences | 1989
John R. Mathias; Karen L. Ferguson; Mary H. Clench
In this informal initial study, four female patients with intractable chronic abdominal pain, daily nausea, intermittent vomiting, and altered stool habits due to “functional” disease were investigated. A gonadotropin-releasing hormone (GnRH) analog agonist, leuprolide acetate (Lupron) [dleu6,Desgly- NH210,Proethylamide9,was administered once daily (0.5 mg subcutaneously) for three months. At the end of the three-month period, three subjects were symptom-free and the fourth experienced only mild and intermittent pain. The leuprolide regimen was continued for an additional three months, and estrogen (0.625 mg orally) and calcium (1000 mg orally) were given daily to prevent osteoporosis. The patients remained symptom-free. A challenge with progesterone then induced recurrence of mild symptoms in each subject. Withdrawing leuprolide induced the baseline symptoms in all patients within three to five days. This regimen has now been continued for up to 15 months, and all four patients have remained generally symptomfree. Progesterone has also been given every three months to induce menses. A fifth patient, with Roux-en-Y syndrome, has also been treated with leuprolide. She is symptom-free after six months and has gained weight. In this initial observation period in patients with severe functional (neuromuscular) bowel disease, the GnRH analog agonist leuprolide controlled pain, nausea, and vomiting. The mechanism of this control is unknown but may involve the neuroendocrine physiology of the hypothalamic-pituitaryovarian axis.
Gastroenterology | 1986
Charles A. Sninsky; Richard H. Davis; Mary H. Clench; Kathleen D. Thomas; John R. Mathias
We performed a double-blind randomized study in 24 healthy volunteers, to evaluate the effects of two doses of lidamidine hydrochloride, loperamide, and placebo on transit of the small intestine and gastric emptying. Transit time of the small intestine was determined by measuring the rise in breath hydrogen excretion after ingestion of lactulose. Although there was a trend for prolonged intestinal transit time in both lidamidine groups, this difference was not significant compared with that in the placebo group. Loperamide significantly slowed transit when compared with placebo or lidamidine (p less than 0.001). Gastric emptying was assessed by using a solid-phase radiolabeled meal. Three parameters of gastric emptying were analyzed: half-emptying time, area under the gastric emptying curve, and beta. Although there was a trend for a longer half-emptying time in the group that received 12 mg of lidamidine, this difference approached, but did not reach, statistical significance (p = 0.06) compared with placebo. The area under the gastric emptying curve, a potentially more sensitive parameter for measuring gastric emptying, was significantly increased in the group receiving 12 and 18 mg of lidamidine (p less than 0.05) compared with the group receiving loperamide or placebo. In summary, lidamidine significantly delayed gastric emptying but had no significant effect on small bowel transit. These data suggest that the antidiarrheal properties of lidamidine are the result of enhanced absorption or inhibition of secretion of fluid and electrolytes.
Digestive Diseases and Sciences | 1994
John R. Mathias; Mary H. Clench; Patricia H. Roberts; Vonda G. Reeves-Darby
We initially investigated the effects of a gonadotropin-releasing hormone analog, leuprolide acetate, in 28 patients with moderate to severe functional bowel disease in a phase-II, randomized, double-blind, and placebo-controlled study using Lupron Depot 3.75 mg (which delivers a continuous low dose of drug for one month) or placebo given intramuscularly. After completing that 12-week study period during which their symptoms had improved significantly (P<0.01–0.5), the 28 patients were allowed to continue receiving leuprolide acetate; they were monitored for an additional 40 weeks. Of those 28, 25 (89%) finished the 52-week treatment. Drug administration was changed from the monthly low-dose form of leuprolide acetate to a daily subcutaneous dose that was gradually increased from 0.5 mg daily to an effective therapeutic dose (1.0–1.5 mg). All subjects received estrogen replacement during this period. Continued use of leuprolide acetate at maximum therapeutic dosage and over longer periods of time produced even more striking and significant changes in the disabling and debilitating symptoms of functional bowel disease. Nausea, abdominal pain, early satiety, anorexia, and abdominal distension decreased markedly (P<0.0001) and vomiting was also reduced (P<0.01) more than in the short-term, low-dosage, double-blind study. Combined total symptom scores and overall assessment also changed significantly in the long-term phase (bothP<0.0001).
Journal of Experimental Zoology | 1999
Mary H. Clench
The avian cecum is a blind-ended sac that extends from the proximal end of the colon. Ceca may be of several different histological types; they range in size from large and paired to very small and single, or they may be completely absent. Cecal types and sizes are summarized herein by taxonomic group. The intestinal type is best known; it may contain fluid, food particles, microorganisms, and substances produced by the ceca. Ceca may serve as the site for several different functions, especially digestion of small food particles, absorption of nutrients, production of immunoglobulins and antibodies, microbial action of beneficial and pathogenic organisms, utilization and absorption of water, and metabolism of uric acid into amino acids. Ceca in turkeys, chickens, and other galliforms have active motility that stirs and periodically evacuates the luminal contents. Contractions of the cecal wall propagate in either direction, with the majority being toward the cecal tip and most numerous when the ceca are filling with digesta. Propagation velocity of the contractions is affected by the presence or absence of food in the lumen. Cecal mixing contractions do not seem to be related to ileal motility. J. Exp. Zool. 283:441–447, 1999.
Digestive Diseases and Sciences | 1992
John R. Mathias; Gordon S. Baskin; Vonda G. Reeves-Darby; Mary H. Clench; Lesa L. Smith; John H. Calhoon
SummaryAfter orthotopic heart-lung transplantation and immunosuppression, a patient developed intractable nausea and vomiting in association with chronic cytomegalovirus infection. Chronic intestinal pseudoobstruction was documented by antroduodenal manometric study. The patient was treated with leuprolide acetate with resolution of symptoms and improvement of intestinal motility abnormality. This case demonstrates an association of chronic viral infection with acquired intestinal motor disorders. Gastrointestinal complications that are common after organ transplantation might be due to acquired neuromuscular disease. The potential efficacy of leuprolide in such neuromuscular disorders provides a rationale for diagnostic motility studies in patients with “functional” gastrointestinal disorders.
Digestive Diseases | 1998
John R. Mathias; Mary H. Clench
Functional disorders of the gastrointestinal tract comprise a common but ill-defined group of diseases; they primarily afflict women. Although predominantly involving nerve and muscle, the cellular and molecular bases of the pathogenesis of these functional disorders are unknown. Clinical studies indicate that some result from neural dysfunction within the enteric nervous system, others may be due to muscular problems, and the causes of still others remain unknown. Laboratory studies have shown that ovarian products such as progesterone, luteinizing hormone, human chorionic gonadotropin, and relaxin (but not estrogen), are neural antagonists of gastrointestinal motility. The production and secretion of these ovarian substances are controlled by gonadotropin-releasing hormone (GnRH) released from the hypothalamus; they probably act on γ-aminobutyric acid receptors and alter chloride influx into the cell. GnRH analogs are effective drugs that downmodulate the hypothalamic-pituitary-gonadal axis and inhibit the secretion of gonadal products involved in such hormone-dependent diseases as endometriosis and prostate cancer. Acting on the GnRH receptors (seven transmembrane domain receptors) on myenteric neurons, GnRH analogs are also effective neural modulators in such disorders as functional bowel disease. These analogs are a promising new group of compounds that may be used to treat difficult gastrointestinal problems.
Journal of Clinical Gastroenterology | 1993
John C. Cozart; Sathya S. Kalangi; Mary H. Clench; Donald R. Taylor; Michael J. Borucki; Richard B. Pollard; Roger D. Soloway
We reviewed the hospital charts of 17 patients with AIDS and Clostridium difficile diarrhea to determine antibiotic use before C. difficile infection, methods of treatment for C. difficile diarrhea, and response of diarrhea to treatment. Left shift and total white blood cell count before and after treatment for C. difficile were also determined. Non-HIV-infected patients with C. difficile diarrhea served as controls. In the patients with AIDS, resolution of diarrhea was noted in 15 (88%) patients. In 25 (76%) control patients, diarrhea resolved with treatment. The patients with AIDS also had a significant decrease (p < 0.05) in left shift in white blood cell count with treatment; the controls did not. Our study therefore suggests that C. difficile diarrhea is at least as likely to resolve with antibiotic therapy in patients with AIDS as it is in those with the non-AIDS-related disorder. We also found that patients with AIDS and C. difficile diarrhea are more likely than patients without AIDS to have a decreased left shift in white blood cell count after antibiotic therapy.
Neurogastroenterology and Motility | 1996
T. E. Ducker; J. W. Boss; S. A. Altug; H. Mehrabian; D. R. Dekeratry; Mary H. Clench; John R. Mathias
Abstract We hypothesized that sex hormones may affect motility disorders because these diseases occur more often in women than in men, and symptoms often occur or worsen after ovulation. Luteinizing hormone (LH) is predominantly secreted by the anterior pituitary midway through the menstrual cycle; it results in the development of the corpus luteum. LH levels also increase after bilateral gonadectomy. LH and human chorionic gonadotropin (hCG) bind to the same receptor, but rats lack hCG. To assess how LH and hCG influence myoelectric activity of the small intestine and to test the specificity of the LH receptor, we implanted electrodes on the jejunum of female rats. LH (0.1 or 0.5 NIH units) was administered intraperitoneally to intact and gonadectomized rats and 0.5 NIH units to rats that had been both hypophysectomized and gonadectomized; intact animals were treated with 100 units USP of hCG. Recordings were made with the rats in fasted and in fed states, and their intestinal motility was analysed. The most striking effects of LH, hypophysectomy, and hCG were the same: phase III of the migrating myoelectric complex was markedly fragmented and its duration lengthened (P < 0.0001). Gonadectomy alone and gonadectomy with hypophysectomy also increased fragmentation and phase III duration (P < 0.01 or better). LH receptors respond similarly to LH and hCG, and both hormones alter myoelectric activity of the rat small intestine in comparable ways.