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1.
Cancer Rep (Hoboken) ; 3(3): e1243, 2020 06.
Article in English | MEDLINE | ID: mdl-32671978

ABSTRACT

BACKGROUND: Small-cell lung cancer (SCLC) represents a group of highly fatal diseases with a tendency toward fast growth, early metastasis, and easy development of chemotherapy resistance. In the past 30 years, few advances have been made in the systemic treatment of SCLC, and cisplatin/etoposide has remained the standard of care for limited-stage SCLC and, in combination with radiotherapy, extensive-stage SCLC. The preferred metastatic sites of SCLC include the brain, liver, adrenal glands, bone, and bone marrow. However, bowel metastasis caused by SCLC is extremely rarely proved in patients while they are still alive (although autopsy studies suggest that silent metastases to the bowel are more common), and the standard treatment for bowel metastasis has never been reported. The mean time between the identification of gastrointestinal metastasis and mortality in patients with lung cancer is 100.6 days, with a range of 21-145 days. CASE: We report the case of a patient with extensive SCLC (including brain metastasis), in which exon 19 deletion of epidermal growth factor receptor (EGFR) was detected. She initially refused chemotherapy and cranial radiotherapy and instead only agreed to oral target therapy. The second-generation EGFR-tyrosine kinase inhibitor (TKI), afatinib, was administered to the patient, and partial remission, including smaller metastatic brain tumors, was noted. Even though the subsequent development of rare metastatic lesions in the ascending and sigmoid colon was proved by colonoscopic biopsies, the prolonged overall survival (400 days) without standard treatment was marked in this case. CONCLUSION: The patient with extensive metastasis of SCLC did not receive standard systemic chemotherapy. Instead, she initially received second-generation EGFR-TKI afatinib alone and later on whole brain radiotherapy as well (3 weeks before she expired). The prolonged overall survival of 400 days was marked and is worthy of sharing and further investigation.


Subject(s)
Afatinib/adverse effects , Colon, Ascending/pathology , Colon, Sigmoid/pathology , Colonic Neoplasms/pathology , Lung Neoplasms/drug therapy , Small Cell Lung Carcinoma/drug therapy , Aged , Antineoplastic Agents/adverse effects , Colon, Ascending/drug effects , Colon, Sigmoid/drug effects , Colonic Neoplasms/chemically induced , Female , Humans , Lung Neoplasms/pathology , Prognosis , Small Cell Lung Carcinoma/secondary
2.
Dtsch Med Wochenschr ; 145(14): 988-990, 2020 07.
Article in German | MEDLINE | ID: mdl-32668470

ABSTRACT

MEDICAL HISTORY AND CLINICAL PRESENTATION: A 66-year-old female patient was admitted to the emergency department following bitter zucchini ingestion. Clinical symptoms were tachycardia, hypotension, somnolence, diarrhea, hematochezia as well as exsiccosis, nausea and emesis. EXAMINATION AND DIAGNOSIS: Laboratory results showed leukocytosis and signs of exsiccosis. Ultrasound revealed thickening of the sigmoid colon wall, interpretable as acute colitis. Poisoning with cucurbitacin containing zucchini was diagnosed. THERAPY: The patient improved after intravenous fluid administration. Hemorrhagic colitis with diarrhea was self limiting. After 2 days, the patient was able to eat again. CONCLUSION: Acute food poisoning due to cucurbitacin - containing pumpkin is rare but can occur in small gardening units in association with higher outside temperatures. Cucurbitacin poisoning has to be taken into account for differential diagnosis in food poisoning. Bitter taste is essential to diagnose cucurbitacin intoxications.


Subject(s)
Cucurbitacins/adverse effects , Foodborne Diseases/diagnosis , Foodborne Diseases/etiology , Aged , Colitis/chemically induced , Colon, Sigmoid/drug effects , Diagnosis, Differential , Diarrhea/chemically induced , Female , Gastrointestinal Hemorrhage/chemically induced , Humans , Leukocytosis/chemically induced , Nausea/chemically induced , Ultrasonography , Vomiting/chemically induced
4.
Mucosal Immunol ; 11(2): 449-461, 2018 03.
Article in English | MEDLINE | ID: mdl-28766555

ABSTRACT

Toll-like receptor 9 (TLR9) agonists are being developed for treatment of colorectal and other cancers, yet the impact of these drugs on human intestines remains unknown. This, together with the fact that there are additional potential indications for TLR9 agonist therapy (e.g., autoimmune and infectious diseases), led us to investigate the impact of MGN1703 (Lefitolimod) on intestinal homeostasis and viral persistence in HIV-positive individuals. Colonic sigmoid biopsies were collected (baseline and week four) from 11 HIV+ individuals on suppressive antiretroviral therapy, who received MGN1703 (60 mg s.c.) twice weekly for 4 weeks in a single-arm, phase 1b/2a study. Within sigmoid mucosa, global transcriptomic analyses revealed 248 modulated genes (false discovery rate<0.05) including many type I interferon (IFN)-stimulated genes. MGN1703 increased the frequencies of cells exhibiting MX1 (P=0.001) and ISG15 (P=0.014) protein expression. No changes were observed in neutrophil infiltration (myeloperoxidase; P=0.97). No systematic effect on fecal microbiota structure was observed (analysis of similarity Global R=-0.105; P=0.929). TLR9 expression at baseline was inversely proportional to the change in integrated HIV DNA during MGN1703 treatment (P=0.020). In conclusion, MGN1703 induced a potent type I IFN response, without a concomitant general inflammatory response, in the intestines.


Subject(s)
Colon, Sigmoid/physiology , DNA/therapeutic use , Gastrointestinal Microbiome/drug effects , HIV Infections/immunology , HIV-1/physiology , Intestines/immunology , Toll-Like Receptor 9/agonists , Colon, Sigmoid/drug effects , Colon, Sigmoid/virology , Cytokines/genetics , Cytokines/metabolism , DNA, Viral/genetics , Female , Gene Expression Profiling , HIV Infections/drug therapy , Homeostasis , Humans , Immunity, Mucosal/drug effects , Interferon Type I/metabolism , Intestines/drug effects , Intestines/virology , Male , Myxovirus Resistance Proteins/genetics , Myxovirus Resistance Proteins/metabolism , Ubiquitins/genetics , Ubiquitins/metabolism , Viral Load/drug effects
5.
J Minim Invasive Gynecol ; 24(7): 1170-1176, 2017.
Article in English | MEDLINE | ID: mdl-28694166

ABSTRACT

STUDY OBJECTIVE: To evaluate the diagnostic accuracy and learning curve of a sonographic mapping protocol for deep endometriosis (DE). DESIGN: Retrospective cohort study (Canadian Task Force classification II-3). SETTING: Tertiary referral center in the United States. PATIENTS: 117 consecutive patients who presented to our gynecology clinic with complaints of significant noncyclic pelvic pain of at least 6 months' duration, and/or clinical findings concerning for deep endometriosis and who were referred for transvaginal ultrasound with bowel preparation. INTERVENTIONS: Patients underwent transvaginal ultrasound with bowel-preparation (TVUS-BP) performed by a single radiologist. Findings suspicious for DE were reported and correlated with surgical and histopathological findings. The duration of the examination and number of cases required to achieve proficiency were calculated for positive, equivocal, and negative findings. MEASUREMENTS AND MAIN RESULTS: Among 117 patients (median age, 35 years; range, 19-54 years) referred for TVUS-BP, 113 had complete examinations. Fifty-seven of these 113 patients underwent surgical exploration within 1 year, and DE was identified surgically in 23 of them. DE of the rectosigmoid colon and/or rectovaginal septum was detected with a sensitivity of 94% (95% confidence interval [CI], 70%-100%) and specificity of 100% (95% CI, 91%-100%). DE of the retrocervical region and/or uterosacral ligaments was detected with a sensitivity of 86% (95% CI, 65%-97%) and specificity of 94% (95% CI, 81%-99%). Proficiency, defined by a flattening of the learning curve, was achieved after 70 to 75 scans. The mean duration of the examination was 42 ± 4 minutes initially, but declined to 15 ± 4 minutes once proficiency was achieved. Cases of equivocal or minimal disease demonstrated the greatest decline in examination duration. CONCLUSION: A newly applied TVUS-BP protocol for detection of pelvic DE is highly accurate and required only a modest learning curve to achieve procedural proficiency in a US tertiary referral center where physicians interpret but typically do not perform TVUS exams. Overcoming diagnostic uncertainty regarding minimal or equivocal disease appeared to be an important factor in the initial learning curve. With adequate training, TVUS-BP may be adapted as a primary diagnostic tool for detecting pelvic DE.


Subject(s)
Cathartics/therapeutic use , Endometriosis/diagnosis , Endometriosis/surgery , Endosonography/methods , Learning Curve , Peritoneal Diseases/diagnosis , Preoperative Care/education , Vagina/diagnostic imaging , Adult , Colon, Sigmoid/diagnostic imaging , Colon, Sigmoid/drug effects , Colon, Sigmoid/pathology , Education, Medical/methods , Endometriosis/pathology , Female , Humans , Middle Aged , Pelvis/diagnostic imaging , Pelvis/pathology , Peritoneal Diseases/pathology , Peritoneal Diseases/surgery , Predictive Value of Tests , Preoperative Care/methods , Rectum/diagnostic imaging , Rectum/drug effects , Rectum/pathology , Retrospective Studies , Sensitivity and Specificity , Tertiary Care Centers , United States , Vagina/pathology , Young Adult
6.
J Minim Invasive Gynecol ; 24(7): 1145-1151, 2017.
Article in English | MEDLINE | ID: mdl-28673872

ABSTRACT

STUDY OBJECTIVE: To compare the accuracy of transvaginal ultrasound (TVUS) with and without bowel preparation (BP) to detect and describe intestinal nodules of deep infiltrating endometriosis (DIE) with laparoscopic findings. DESIGN: A prospective study of paired data (Canadian Task Force classification II.1). SETTING: A tertiary university hospital from November 2014 to November 2015. PATIENTS: A cohort of women awaiting surgery for endometriosis. INTERVENTIONS: The wall of the rectum and the lower sigmoid colon of the patients were evaluated by 2 TVUSs: the first ultrasound was performed without previous BP, and the second was done after a 3-day low-residue diet and two 250-mL enemas 12 hours and 3 hours before TVUS. MEASUREMENTS AND MAIN RESULTS: The presence or absence of rectosigmoid nodules visualized by TVUS with and without BP was compared with laparoscopic results. Forty patients with a mean age of 36.8 ± 5.0 years were included in the study. By comparing the surgical findings histologically confirmed (the presence or absence of bowel nodules and localization) with those of the 2 TVUSs with and without BP, the sensitivity, specificity, and Cohen kappa were 100%, 96%, and 0.95 and 73%, 88%, and 0.61, respectively. Laparoscopy showed that up to 37.5% of patients (15/40) presented bowel involvement. Variables were clearly more evaluable with than without BP. CONCLUSION: TVUS with BP has a higher accuracy than TVUS without BP. BP allows and facilitates the detection of more rectal nodules of DIE in patients with suspected endometriosis and surgical criteria.


Subject(s)
Cathartics/therapeutic use , Endometriosis/diagnosis , Endosonography/methods , Rectal Diseases/diagnosis , Sigmoid Diseases/diagnosis , Vagina/diagnostic imaging , Adult , Colon, Sigmoid/diagnostic imaging , Colon, Sigmoid/drug effects , Colon, Sigmoid/pathology , Endometriosis/surgery , Female , Humans , Laparoscopy , Peritoneal Diseases/diagnosis , Peritoneal Diseases/surgery , Preoperative Care/methods , Rectal Diseases/surgery , Rectum/diagnostic imaging , Rectum/drug effects , Rectum/pathology , Sensitivity and Specificity , Sigmoid Diseases/surgery , Young Adult
7.
World J Gastroenterol ; 23(21): 3934-3944, 2017 Jun 07.
Article in English | MEDLINE | ID: mdl-28638234

ABSTRACT

A 48-year-old woman was admitted with 15-mo history of abdominal pain, diarrhea and hematochezia, and 5-mo history of defecation difficulty. She had been successively admitted to nine hospitals, with an initial diagnosis of inflammatory bowel disease with stenotic sigmoid colon. Findings from computed tomography virtual colonoscopy, radiography with meglumine diatrizoate, endoscopic balloon dilatation, metallic stent implantation and later overall colonoscopy, coupled with the newfound knowledge of compound Qingdai pill-taking, led to a subsequent diagnosis of ischemic or toxic bowel disease with sigmoid colon stenosis. The patient was successfully treated by laparoscopic sigmoid colectomy, and postoperative pathological examination revealed ischemic or toxic injury of the sigmoid colon, providing a final diagnosis of drug-induced sigmoid colon stenosis. This case highlights that adequate awareness of drug-induced colon stenosis has a decisive role in avoiding misdiagnosis and mistreatment. The diagnostic and therapeutic experiences learnt from this case suggest that endoscopic balloon expansion and colonic metallic stent implantation as bridge treatments were demonstrated as crucial for the differential diagnosis of benign colonic stenosis. Skillful surgical technique and appropriate perioperative management helped to ensure the safety of our patient in subsequent surgery after long-term use of glucocorticoids.


Subject(s)
Colon, Sigmoid/drug effects , Constriction, Pathologic/diagnosis , Diarrhea/diagnosis , Drugs, Chinese Herbal/adverse effects , Inflammatory Bowel Diseases/diagnosis , Intestinal Obstruction/diagnosis , Pityriasis Rosea/drug therapy , Abdominal Pain/etiology , Abdominal Pain/therapy , Anti-Bacterial Agents/therapeutic use , Biopsy , Colectomy/methods , Colon, Sigmoid/diagnostic imaging , Colon, Sigmoid/pathology , Colon, Sigmoid/surgery , Colonography, Computed Tomographic , Colonoscopy/instrumentation , Colonoscopy/methods , Constipation/etiology , Constriction, Pathologic/chemically induced , Constriction, Pathologic/complications , Constriction, Pathologic/therapy , Contrast Media/administration & dosage , Diagnosis, Differential , Diarrhea/etiology , Diarrhea/microbiology , Diatrizoate Meglumine/administration & dosage , Dilatation/methods , Female , Fluid Therapy , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/therapy , Humans , Intestinal Obstruction/chemically induced , Intestinal Obstruction/complications , Intestinal Obstruction/therapy , Laparoscopy/methods , Levofloxacin/therapeutic use , Middle Aged , Self Expandable Metallic Stents
8.
J Clin Pharm Ther ; 41(6): 725-726, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27624676

ABSTRACT

WHAT IS KNOWN AND OBJECTIVE: There have been several reports describing rectovaginal fistula development after bevacizumab treatment, and these fistulas were diagnosed by CT scan or colonoscopy. We report a case of sigmoid-vaginal fistula diagnosed by fistulography. CASE DESCRIPTION: The case is a 53-year-old woman who was treated for chronic myelogenous leukaemia and gynaecological cancers 8 years previously. At 52 years of age, she was diagnosed with colon cancer and had a partial colectomy performed. One year after surgery, colon cancer recurred, and she was treated with anticancer agents, including bevacizumab. During chemotherapy, she complained of a foul smelling discharge from the vagina. Fistulography revealed a sigmoid-vaginal fistula. WHAT IS NEW AND CONCLUSION: This is the first report of vaginal fistulography performed on a patient who was treated with bevacizumab. Fistulography may be useful for detecting sigmoid-vaginal fistula.


Subject(s)
Angiogenesis Inhibitors/adverse effects , Bevacizumab/adverse effects , Colon, Sigmoid/drug effects , Vaginal Fistula/chemically induced , Angiogenesis Inhibitors/therapeutic use , Bevacizumab/therapeutic use , Colonic Neoplasms/drug therapy , Female , Humans , Middle Aged , Neoplasm Recurrence, Local/drug therapy
9.
Physiol Genomics ; 48(9): 651-9, 2016 09 01.
Article in English | MEDLINE | ID: mdl-27401218

ABSTRACT

The strength of associations between various exposures (e.g., diet, tobacco, chemopreventive agents) and colorectal cancer risk may partially depend on the complex interaction between epithelium and stroma across anatomic subsites. Currently, baseline data describing genome-wide coding and long noncoding gene expression profiles in the healthy colon specific to tissue type and location are lacking. Therefore, colonic mucosal biopsies from 10 healthy participants who were enrolled in a clinical study to evaluate effects of lignan supplementation on gut resiliency were used to characterize the site-specific global gene expression signatures associated with stromal vs. epithelial cells in the sigmoid colon and rectum. Using RNA-seq, we demonstrate that tissue type and location patterns of gene expression and upstream regulatory pathways are distinct. For example, consistent with a key role of stroma in the crypt niche, mRNAs associated with immunoregulatory and inflammatory processes (i.e., CXCL14, ANTXR1), smooth muscle contraction (CALD1), proliferation and apoptosis (GLP2R, IGFBP3), and modulation of extracellular matrix (MMP2, COL3A1, MFAP4) were all highly expressed in the stroma. In comparison, HOX genes (HOXA3, HOXD9, HOXD10, HOXD11, and HOXD-AS2, a HOXD cluster antisense RNA 2), and WNT5B expression were also significantly higher in sigmoid colon compared with the rectum. These findings provide strong impetus for considering colorectal tissue subtypes and location in future observational studies and clinical trials designed to evaluate the effects of exposures on colonic health.


Subject(s)
Colon, Sigmoid/metabolism , Colon/metabolism , Epithelial Cells/metabolism , Rectum/metabolism , Adult , Biopsy , Colon/drug effects , Colon/pathology , Colon, Sigmoid/drug effects , Colon, Sigmoid/pathology , Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , Cross-Over Studies , Double-Blind Method , Epithelial Cells/drug effects , Epithelial Cells/pathology , Epithelium/drug effects , Epithelium/metabolism , Epithelium/pathology , Extracellular Matrix/drug effects , Extracellular Matrix/genetics , Extracellular Matrix/metabolism , Extracellular Matrix/pathology , Female , Gene Expression Profiling/methods , Humans , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Lignans/administration & dosage , Male , Middle Aged , RNA, Messenger/metabolism , Rectum/drug effects , Rectum/pathology , Transcriptome/drug effects , Transcriptome/genetics , Young Adult
10.
Acta Oncol ; 55(11): 1285-1293, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27173757

ABSTRACT

BACKGROUND: To analyze the relationship between mean radiation dose to the bowels and the anal-sphincter and occurrence of 'defecation into clothing without forewarning', a specific and serious fecal incontinence symptom after gynecological radiotherapy. Additional potential risk factors associated with the symptom are explored. MATERIAL AND METHODS: Data were collected for 519 eligible gynecological cancer survivors, treated with pelvic radiotherapy, with a median follow-up of 5.8 years, using a study-specific questionnaire and medical records. Correlations between defecation into clothing without forewarning and mean dose to organs at risk; the anal-sphincter region, the rectum, the sigmoid and the small intestines were investigated, also taking other risk factors into account. RESULTS: Twelve percent reported having had the symptom at least once in the preceding six months. Mean doses >50 Gy to the anal-sphincter region, the rectum, the sigmoid and the small intestines were related to the occurrence of the symptom. Significantly associated risk factors were deliveries with high birth weight, heart failure and lactose and/or gluten intolerance. After adjusting for these factors, mean doses >50 Gy to the anal-sphincter region, the sigmoid and the small intestines remained related to the occurrence of the symptom. CONCLUSION: Mean doses to the bowels and anal-sphincter region are related to the risk of defecation into clothing without forewarning in long-term gynecological cancer survivors treated with pelvic radiotherapy. Further radiobiological modeling may distinguish which organ(s) contribute most to development of the symptom.


Subject(s)
Fecal Incontinence/etiology , Genital Neoplasms, Female/radiotherapy , Radiotherapy Dosage , Radiotherapy/adverse effects , Adult , Aged , Anal Canal/radiation effects , Brachytherapy/adverse effects , Colon, Sigmoid/drug effects , Female , Genital Neoplasms, Female/complications , Humans , Middle Aged , Multivariate Analysis , Organs at Risk , Rectum/drug effects , Risk Factors , Surveys and Questionnaires , Survivors
11.
BMC Gastroenterol ; 16: 20, 2016 Feb 24.
Article in English | MEDLINE | ID: mdl-26911806

ABSTRACT

BACKGROUND: Optimal phosphorous control is an important aspect of the care of patients with end-stage renal disease, and phosphate binders are usually needed. CASE PRESENTATION: A 74-year-old woman with end-stage renal disease on maintenance hemodialysis presented to the emergency room with abdominal discomfort, rectal pain, and blood-tinged stools. Initial concern was for a rectal carcinoma, based on the symptoms and imaging in initial computerized tomography of the abdomen showing rectal wall thickening, and her clinical presentation. She had been treated with the phosphate binder sevelamer for two months. In this case report, we explore the unique features of sevelamer-associated recto-sigmoid ulcers which led to her symptoms. CONCLUSION: Sevelamer is widely used in chronic kidney disease and end-stage renal disease patients with hyperphosphatemia. It is a crosslinked polymeric amine that binds phosphates and bile acids; it is not systemically absorbed. To the authors' knowledge, this is the first reported case of recto-sigmoid ulcers associated with use of this phosphate binder. Nephrologists, pathologists, and gastroenterology sub-specialists should be aware of this recently-reported entity in patients on sevelamer with suggestive symptoms, as this medication is widely used in renal patients.


Subject(s)
Chelating Agents/adverse effects , Kidney Failure, Chronic/drug therapy , Proctocolitis/chemically induced , Sevelamer/adverse effects , Ulcer/chemically induced , Aged , Colon, Sigmoid/drug effects , Female , Humans , Rectum/drug effects , Renal Dialysis
12.
Scand J Gastroenterol ; 51(5): 538-47, 2016.
Article in English | MEDLINE | ID: mdl-26610166

ABSTRACT

OBJECTIVE: Opioid therapy is associated with altered secretion and motility of the gut. The relative contribution of decreased secretion to the development of opioid-induced constipation remains unknown. MATERIALS AND METHODS: Twenty-five healthy males were treated with oxycodone for 5 d in a placebo-controlled, randomised cross-over design. Gastrointestinal adverse effects were assessed with validated questionnaires (bowel function index and gastrointestinal symptom rating scale). Rectosigmoid mucosal biopsies were taken at baseline and on day 5 during both treatments and mounted in Ussing chambers. Electrogenic ion transport parameters (short circuit current (SCC) and slope conductance) were measured after addition of secretagogues (prostaglandin E2 (PGE2) (6 µm), theophylline (400 µm)), and an inhibitor (ouabain (200 µm)). Additionally, morphine (50 µm) was added to investigate the direct opioid effect on colonic mucosa. RESULTS: Questionnaires showed pronounced bowel symptoms, including constipation during oxycodone treatment (eight-fold increase in bowel function index score from day 1 to day 5 (p < 0.001) while no significant change occurred during placebo treatment (p = 0.47). Basal SCC and slope conductance did not differ between treatments (all p > 0.05) and application with PGE2, theophylline, and ouabain yielded comparable results on all examinations (all p > 0.05). Morphine application consistently did not evoke a change in ion transport. CONCLUSION: Compared to placebo, epithelial electrogenic ion transport is not altered in mucosal biopsies from the rectosigmoid colon following 5-d oxycodone treatment. The secretory mechanisms in isolated mucosa appear to play a negligible role in the development of opioid-induced constipation.


Subject(s)
Colon, Sigmoid/metabolism , Gastrointestinal Motility/drug effects , Intestinal Mucosa/metabolism , Oxycodone/administration & dosage , Rectum/metabolism , Adult , Analgesics, Opioid/administration & dosage , Biopsy , Colon, Sigmoid/drug effects , Colon, Sigmoid/pathology , Constipation/chemically induced , Constipation/diagnosis , Constipation/physiopathology , Cross-Over Studies , Dose-Response Relationship, Drug , Follow-Up Studies , Healthy Volunteers , Humans , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , Ion Transport/drug effects , Male , Middle Aged , Rectum/drug effects , Rectum/pathology , Time Factors , Young Adult
14.
Saudi J Gastroenterol ; 21(5): 290-4, 2015.
Article in English | MEDLINE | ID: mdl-26458855

ABSTRACT

BACKGROUND/AIM: Aerobic metabolism is necessary for ion transport in many transporting epithelia, including the human colonic epithelium. We assessed the effects of the epithelial sodium channel blocker, amiloride, on oxygen consumption and short-circuit current of the human sigmoid epithelium to determine whether these effects were influenced by the age of the subject. MATERIALS AND METHODS: Segments of the sigmoid colon were obtained from the safety margin of resections performed in patients of 62-77 years of age. Isolated mucosa preparations were obtained and mounted in airtight Ussing chambers, fit for simultaneous measurement of short-circuit current and oxygen concentration, before and after blocking epithelial sodium channels with amiloride (0.1 mmol/L). Regression analyses were performed to assess the associations between short-circuit current, oxygen consumption, and age of the subject as well as to define the relationship between the decreases in short-circuit current and oxygen consumption after blockade. RESULTS: Epithelial sodium channel blockade caused an 80% reduction in short-circuit current and a 26% reduction in oxygen consumption. Regression analysis indicated that both changes were significantly related (r = 0.884;P = 0.0007). Oxygen consumption decreased by 1 m mol/h/cm2 for each 25 m A/cm2 decrease in short-circuit current. Neither short-circuit current nor oxygen consumption had any significant relationship with the age of the subjects. CONCLUSION: The decrease in epithelial oxygen consumption caused by amiloride is proportional to the decrease in short-circuit current and independent of the age of the subject.


Subject(s)
Amiloride/pharmacology , Colon, Sigmoid/drug effects , Diuretics/pharmacology , Epithelium/drug effects , Oxygen Consumption/drug effects , Sodium/metabolism , Age Factors , Aged , Cations, Monovalent/metabolism , Colon, Sigmoid/metabolism , Epithelial Sodium Channel Blockers/pharmacology , Epithelium/metabolism , Female , Humans , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism , Ion Transport/drug effects , Male , Middle Aged
15.
Acta Physiol (Oxf) ; 215(1): 37-45, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26052867

ABSTRACT

AIM: To analyse the effects of angiotensin II (Ang II) on the contractility of human sigmoid colon, and to characterize the subtype(s) of receptor(s) involved and the related action mechanism. METHODS: The contractility of sigmoid colon circular muscle strips was recorded isometrically. RT-PCR and immunohistochemistry were used to reveal the eventual existence of a local renin-angiotensin system (RAS) and the distribution of Ang II receptors. RESULTS: Transcripts encoding for the Ang II type 1 (AT1 ) and the Ang II type 2 (AT2 ) receptor subtypes and for the angiotensin-converting enzyme in the whole-thickness muscular wall were observed. Ang II caused a concentration-dependent contractile response, which is antagonized by losartan, AT1 receptor antagonist, but not by PD123319, AT2 receptor antagonist. The joint application of losartan and PD123319 did not produce any additive effect. The contractile response to Ang II was partially reduced by tetrodotoxin, Na(+) voltage-gated neural channel blocker, and to some extent by SR48968, tachykinin NK2 receptor antagonist. However, hexamethonium, nicotinic receptor antagonist, atropine, cholinergic muscarinic receptor antagonist and SR140333, tachykinin NK1 receptor antagonist, were ineffective. Immunohistochemical analysis showed that AT1 receptors were expressed on the smooth muscle layers and myenteric plexus. CONCLUSION: Ang II positively modulates the spontaneous contractile activity of human sigmoid colon via activation of post-junctional and pre-junctional AT1 receptors, the latter located on the enteric nerves that modulate the release of tachykinins. The presence of the components of RAS in the human colon suggests that Ang II can be also locally generated to control colonic motility.


Subject(s)
Angiotensin II/pharmacology , Colon, Sigmoid/drug effects , Colon, Sigmoid/metabolism , Receptor, Angiotensin, Type 1/metabolism , Receptor, Angiotensin, Type 2/metabolism , Renin-Angiotensin System/drug effects , Aged , Aged, 80 and over , Female , Humans , Imidazoles/pharmacology , Male , Middle Aged , Muscle Contraction/drug effects , Muscle, Smooth, Vascular/drug effects , Peptidyl-Dipeptidase A/metabolism , Pyridines/pharmacology , Renin-Angiotensin System/physiology
16.
Neurogastroenterol Motil ; 27(8): 1098-109, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25974622

ABSTRACT

BACKGROUND: Local release of mast cell proteases during gastrointestinal surgery is associated with the inhibition of motility and postoperative ileus (POI). We determined whether activation of intramuscular mast cell affects the motor patterns of the human ileum and colon and whether proteases are involved. METHODS: Motor response of ileal and colonic circular muscle strips was measured in organ bath. Mast cell degranulation was induced by compound 48/80 (c48/80; 25-675 µg/mL). Motor response was quantified as tone, rhythmic phasic contractions (RPCs) and contractions to electric field stimulation (EFS; 40 Hz), and bethanechol-evoked contractions. Ketotifen (10(-6) mol/L) and a protease inhibitor cocktail (P8340) were used to evaluate the role of mast cell mediators. KEY RESULTS: (a) c48/80 impaired the spontaneous and the electrically evoked motor response in small bowel and colonic strips (sigmoid colon EC50 : 460.0 µg/mL for RPCs and 8.9 µg/mL for electrically evoked contraction amplitudes) and bethanechol-evoked contractions. (b) Preincubation with ketotifen (10(-6) mol/L, 1 h) prevented the impairment of RPCs and EFS-evoked contractions in the sigmoid colon and ileum but not in the right colon. (c) Preincubation with P8340 also prevented the impairment of contractions in the sigmoid colon but not in the ileum or the right colon. CONCLUSIONS & INFERENCES: Mast cell degranulation by c48/80 inhibits the spontaneous and the nerve-mediated motor response in the human ileum and colon. The effect is partially mediated by mast cell proteases and could be relevant in the pathophysiology of POI.


Subject(s)
Cell Degranulation , Colon, Sigmoid/physiology , Ileum/physiology , Mast Cells/physiology , p-Methoxy-N-methylphenethylamine/pharmacology , Adult , Aged , Aged, 80 and over , Colon, Sigmoid/drug effects , Female , Humans , Ileum/drug effects , Ileus/complications , Ileus/physiopathology , In Vitro Techniques , Ketotifen/pharmacology , Male , Mast Cells/drug effects , Middle Aged , Muscle Contraction/drug effects , Postoperative Complications , Protease Inhibitors/pharmacology
18.
AIDS Res Hum Retroviruses ; 29(11): 1487-95, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23885722

ABSTRACT

Rectally applied antiretroviral microbicides for preexposure prophylaxis (PrEP) of HIV infection are currently in development. Since enemas (rectal douches) are commonly used by men who have sex with men prior to receptive anal intercourse, a microbicide enema could enhance PrEP adherence by fitting seamlessly within the usual sexual practices. We assessed the distribution, safety, and acceptability of three enema types-hyperosmolar (Fleet), hypoosmolar (distilled water), and isoosmolar (Normosol-R)-in a crossover design. Nine men received each enema type in random order. Enemas were radiolabeled [(99m)Tc-diethylene triamine pentaacetic acid (DTPA)] to assess enema distribution in the colon using single photon emission computed tomography/computed tomography (SPECT/CT) imaging. Plasma (99m)Tc-DTPA indicated mucosal permeability. Sigmoidoscopic colon tissue biopsies were taken to assess injury as well as tissue penetration of the (99m)Tc-DTPA. Acceptability was assessed after each product use and at the end of the study. SPECT/CT imaging showed that the isoosmolar enema had greater proximal colonic distribution (up to the splenic flexure) and greater luminal and colon tissue concentrations of (99m)Tc-DTPA when compared to the other enemas (p<0.01). Colon biopsies also showed that only the hyperosmolar enema caused sloughing of the colonic epithelium (p<0.05). In permeability testing, the hypoosmolar enema had higher plasma (99m)Tc-DTPA 24-h area under the concentration-time curve and peak concentration compared to the hyperosmolar and isoosmolar enemas, respectively. Acceptability was generally good with no clear preferences among the three enema types. The isoosmolar enema was superior or similar to the other enemas in all categories and is a good candidate for further development as a rectal microbicide vehicle.


Subject(s)
Anti-Infective Agents/administration & dosage , Enema/adverse effects , Enema/methods , HIV Infections/prevention & control , Patient Acceptance of Health Care , Solutions/administration & dosage , Solutions/chemistry , Biopsy , Colon, Sigmoid/drug effects , Colon, Sigmoid/pathology , Humans , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , Male , Solutions/pharmacokinetics , Tomography, Emission-Computed, Single-Photon
19.
Prostaglandins Other Lipid Mediat ; 100-101: 22-9, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23380599

ABSTRACT

Endocannabinoids are protective in animal colitis models. As endocannabinoids also form novel prostaglandin ethanolamides (prostamides) via COX-2, we investigated the effects of prostamides and other COX-2 mediators on tissue damage in an ex vivo human mucosal explant colitis model. Healthy human colonic mucosae were incubated with pro-inflammatory cytokines TNF-α and IL-1ß to elicit colitis-like tissue damage. The PGF-ethanolamide analogue, bimatoprost decreased colitis scores which were reversed by a prostamide-specific antagonist AGN 211334, but not the FP receptor antagonist AL-8810. PGF-ethanolamide and PGE-ethanolamide also reduced cytokine-evoked epithelial damage. Anandamide was protective in the explant colitis model; however COX-2 inhibition did not alter its effects, associated with a lack of COX-2 induction in explant mucosal tissue. These findings support an anti-inflammatory role for prostamides and endocannabinoids in the human colon.


Subject(s)
Colitis/prevention & control , Colon, Sigmoid/drug effects , Dinoprostone/analogs & derivatives , Adult , Amides/pharmacology , Arachidonic Acids/pharmacology , Bimatoprost , Cloprostenol/analogs & derivatives , Cloprostenol/pharmacology , Colitis/metabolism , Colon, Sigmoid/metabolism , Colon, Sigmoid/pathology , Cyclooxygenase 2/metabolism , Cyclooxygenase Inhibitors/pharmacology , Dinoprost/analogs & derivatives , Dinoprost/pharmacology , Dinoprostone/pharmacology , Endocannabinoids/pharmacology , Female , Humans , Immunohistochemistry , Interleukin-1beta/pharmacology , Male , Middle Aged , Oxazoles/pharmacology , Polyunsaturated Alkamides/pharmacology , Receptors, Prostaglandin/antagonists & inhibitors , Receptors, Prostaglandin/metabolism , Sulfonamides/pharmacology , Tissue Culture Techniques , Tumor Necrosis Factor-alpha/pharmacology , Young Adult
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