Effect of Physical Activity on the Association Between Dietary Fiber and Constipation: Evidence From the National Health and Nutrition Examination Survey 2005-2010.

Background/Aims: The effect of physical activity on the relationship between dietary fiber intake and constipation has not been comprehensively studied. This study aims to explore the impact of physical activity. Methods: Data were obtained from 3 cycles of the National Health and Nutrition Examination Survey (NHANES) 2005-2010 and included a total of 13 941 participants aged ≥ 20 years. Multiple logistic regression analysis was used to investigate the independent association between dietary fiber and constipation. Interaction analysis was also performed to analyze the relationship between dietary fiber and constipation in different physical activity groups. Results: Among non-active participants, dietary fiber intake did not associate with stool consistency (OR, 1.02; 95% CI, 0.98-1.05; P = 0.407). For physically active participants, 1-gram unit increase in dietary fiber intake reduced the risk of stool consistency by 3% (OR, 0.97; 95% CI, 0.94-0.99; P = 0.020). Moreover, the relationship between dietary fiber intake and stool consistency was significantly different for groups with different levels of physical activity (P interaction = 0.044). However, dietary fiber intake was not related to stool frequency among non-active participants (OR, 0.99; 95% CI, 0.94-1.05; P = 0.767) nor physically active participants (OR, 1.01; 95% CI, 0.97-1.04; P = 0.751). Conclusions: Increasing dietary fiber intake was associated with stool consistency-related constipation among physically active participants, but not among non-active participants. However, increasing dietary fiber intake is not significantly associated with stool frequency in different physical activity groups.

Abdominal ventral rectopexy with colectomy for obstructed defecation syndrome: An alternative option for selected patients.

BACKGROUND: Abdominal ventral rectopexy (AVR) with colectomy is controversial in the treatment of obstructed defecation syndrome (ODS). Literature data on this technique for ODS are very limited. AIM: To evaluate the safety and efficacy of AVR with colectomy for selected patients with ODS. METHODS: Consecutive patients who underwent AVR with colectomy for ODS were identified prospectively from 2016 to 2017 in our department. Patient demographics, perioperative surgical results, and postoperative follow-up outcomes were collected and analyzed. Long-term follow-up was evaluated with standardized questionnaires. The severity of symptoms was assessed by the objective Wexner Constipation Score (WCS) and ODS Score. The quality of life was assessed by the Patients Assessment of Constipation Quality of Life score. Functional outcome was compared pre- and post-operatively for each patient. The primary outcomes were determined by the improvement in symptoms and quality of life. Secondary outcome measures were operating time, postoperative length of stay, morbidity and mortality, improvement of pelvic floor structure, and patient satisfaction. RESULTS: Four patients underwent robotic-assisted surgery, and two patients underwent a laparoscopic-assisted procedure. The mean operating time for the robotic approach was 243 min (range 160-300 min), and the mean operating time for the laparoscopic approach was 230 min (range 220-240 min). The mean postoperative length of stay was 8.2 d (range 6-12 d). There was no conversion to open procedure and no postoperative mortality. No urinary retention, wound infection, prolonged ileus, pelvic infection and anastomosis leakage occurred. Six patients were followed up for 36 mo. The WCS, ODS, and Patients Assessment of Constipation Quality of Life score improved significantly postoperatively (P < 0.05). The WCS and ODS scores showed the best remission and stabilization at 6 to 12 mo after surgery. There was no recurrence or novel constipation after surgery. None of the patients used laxative medication. CONCLUSION: Robotic and laparoscopic-assisted ventral rectopexy with colectomy is a safe and effective procedure for selected patients with ODS. However, comprehensive preoperative evaluation and careful patient selection are essential.

Defecation function and quality of life in patients with slow-transit constipation after colectomy.

BACKGROUND: Although total or subtotal colectomy for slow-transit constipation (STC) has been proven to be a definite treatment, the associated defecation function and quality of life (QOL) are rarely studied. AIM: To evaluate the effectiveness of surgery for STC regarding defecation function and QOL. METHODS: From March 2013 to September 2017, 30 patients undergoing surgery for STC in our department were analyzed. Preoperative, intra-operative, and postoperative 3-mo, 6-mo, 1-year, and 2-year follow-up details were recorded. Defecation function was assessed by bowel movements, abdominal pain, bloating, straining, laxative, enema use, diarrhea, and the Wexner constipation and incontinence scales. QOL was evaluated using the gastrointestinal QOL index and the 36-item short form survey. RESULTS: The majority of patients (93.1%, 27/29) stated that they benefited from the operation at the 2-year follow-up. At each time point of the follow-up, the number of bowel movements per week significantly increased compared with that of the preoperative conditions (P < 0.05). Similarly, compared with the preoperative values, a marked decline was observed in bloating, straining, laxative, and enema use at each time point of the follow-up (P < 0.05). Postoperative diarrhea could be controlled effectively and notably improved at the 2-year follow-up. The Wexner incontinence scores at 6-mo, 1-year, and 2-year were notably lower than those at the 3-mo follow-up (P < 0.05). Compared with those of the preoperative findings, the Wexner constipation scores significantly decreased following surgery (P < 0.05). Thus, it was reasonable to find that the gastrointestinal QOL index scores clearly increase (P < 0.05) and that the 36-item short form survey results displayed considerable improvements in six spheres (role physical, role emotional, physical pain, vitality, mental health, and general health) following surgery. CONCLUSION: Total or subtotal colectomy for STC is not only effective in alleviating constipation-related symptoms but also in enhancing patients' QOL.

The impact of sedation on quality metrics of colonoscopy: a single-center experience of 48,838 procedures.

PURPOSE: Investigation of the role of sedation during colonoscopy is meaningful as the advantages of colonoscopy performing with sedation are still controversial. METHODS: Medical records of patients who underwent colonoscopy in our institution were retrospectively analyzed. The sedation rate, adenoma detection rate (ADR), polyp detection rate (PDR), cecal intubation rate (CIR), iatrogenic colonic perforation rate (ICP) were calculated. RESULTS: A total of 48,838 colonoscopies (24,498 in males) dated from July 2007 to February 2017 were analyzed. The median age was 50 years (range 16-85 years). An overall sedation rate was 80.38%. The PDR was 26.77%, and was not statistically different between colonoscopy with or without sedation (26.67% vs 27.22, p = 0.474). ADR was 12.9% regardless of applying sedation or not (13.0% vs 12.44%, p = 0.337). The CIR was 87.42% in all examinations with an adjusted CIR of 90.34%, and was higher when performed with sedation than without sedation (88.92% vs 80.64%, p < 0.0001). Five cases (0.01%) of ICP were reported, all of which occurred in patients under sedation. CONCLUSIONS: The use of sedation is associated with increased CIR, but ADR and PDR remain unchanged with or without sedation. However, perforation rate, albeit very low, is significantly higher in sedated patients.

Transanal total mesorectal excision for rectal cancer: a multicentric cohort study.

BACKGROUND: Transanal total mesorectal excision (taTME) has recently emerged as a promising novel surgical procedure for rectal cancer. It is believed to hold the potential advantage of providing better access to mobilize the distal rectum and achieving better pathologic results. This study aimed to evaluate the feasibility of taTME for rectal cancer and summarize the preliminary experience in 10 Chinese hospitals. METHODS: A total of 211 patients were enrolled in this study. Variables for evaluation of safety, feasibility, and oncologic outcomes were retrospectively collected and analysed. RESULTS: The median distance between the tumor and the anal verge was 5.9 cm (range, 1.5-12 cm). The median operating time was 280 min (range, 70-600 min) and the median estimated intra-operative blood loss was 50 mL (range, 10-1,500 mL). The overall rate of complication was 27.9%. Among the 211 patients, 175 (82.9%) had complete TME and 33 (15.6%) had near complete TME. The circumferential resection margin was negative in 97.7% of patients. The patients were followed for a median of 35 months (range, 2-86 months). There was 7.6% (16) mortality, 6.2% (13) had local recurrence, and 12.8% (27) had systemic recurrence. Kaplan-Meier survival analysis showed that 1-, 2-, and 3-year disease-free survival rates were 94.8%, 89.3%, and 80.2%, respectively, and 1-, 2-, and 3-year OS rates were 97.4%, 95.7%, and 92.9%, respectively. CONCLUSIONS: Although limited by its retrospective nature, taTME was safe and feasible in selected patients. Future work with rigorous data recording is warranted.

[Revisional surgery for nonstandard gastric bypass: a case report].

Bariatric surgery is the most effective treatment for obesity with or without type 2 diabetes mellitus and its complications. With the growing incidence of type 2 diabetes mellitus, the number of hospitals performing bariatric surgery and surgical cases increase substantially. The problems in operation standardization, quality control of operation and postoperative management of the patients cause the failure in weight loss, hypoglycemia and severe complications, and revisional surgery is often required to correct the condition. We report a case of laparoscopic revisional surgery following nonstandard gastric bypass, and the reasons for failure of weight loss in first bariatric surgery, the current situation of bariatric surgery and revisional metabolic surgery were analyzed. This case demonstrates the clinical necessity of revisonal bariatric surgery and the importance of selection of the surgical approaches and indications.

APE1 promotes antioxidant capacity by regulating Nrf-2 function through a redox-dependent mechanism.

APE1 is a multifunctional protein that has recently been implicated in protecting cells from oxidative stress. In the current study, we confirmed that APE1׳s effect on cellular antioxidant capacity is related to its redox activity through the use of an APE1 functional mutant, and we investigated the mechanism through which this multifunctional protein affects the function of the transcription factor Nrf-2 in regulating oxidative stress-induced genes. Using a pair of mutants for both the redox activity and the acetylation-regulated activity of APE1, in vitro assays showed that the redox activity of APE1 is crucial for its nuclear association with Nrf-2 and subsequent activation of Nrf-2׳s transcription of several downstream genes during oxidative challenge. Important oxidative stress genes are affected by APE1 redox activity, including Hmox1, Gstm1, and Txnrd1. In addition, utilizing human non-small-cell lung cancer sample tissue as well as a nude mouse xenograft model, we determined that APE1 expression levels are inversely correlated to oxidative stress in vivo. These findings indicated that interference with these crucial functions of APE1 shows promise in preventing resistance to certain radiotherapies and that further research is necessary to understand APE1׳s complex roles in regulating both the basal redox status and the oxidative stress state of the cellular environment.

Neonatal colon perforation due to anorectal malformations: can it be avoided?

Anorectal malformations (ARM) are common anomalies in neonates. Diagnostic and therapeutic delays in the management of ARM may lead to colonic perforation, and even death. Physical examination of the perineum is often sufficient to diagnose ARM in neonates. Notwithstanding, delayed diagnosis of ARM has become increasingly familiar to surgeons, as evidenced by the number of recent publications on this topic in the literature. In this commentary, we discuss spontaneous colonic perforation due to delayed diagnosis of ARM in neonates, and highlight the importance of early diagnosis in assuring good outcomes with surgical management. At this point, a thorough examination of the perineum during the initial newborn assessment is mandatory, particularly in those patients presenting with abdominal signs or symptoms.

[Pathophysiology of slow transit constipation].

Slow transit constipation(STC)is the common type of chronic idiopathic constipation. Due to failure of routine conservative treatment, laxatives abuse is the most choice for majority of the patients, which could damage the enteric nervous system and result in aggravation of constipation. Resection of the slow transit colon is the ultimate option for some patients. It is hard to prevent and treat STC clinically because of the unknown pathophysiologic mechanism. Abnormalities of enteric neurotransmitters such as VIP, SP, NOS and decreased number of interstitial cells of Cajal have been described in the colon of the patients with STC. However, long term application of stimulant laxatives can also result in the almost same changes in the colon. Exploration of the potential relationship among the above reported abnormalities is the direction of future study.

Sympathetic and parasympathetic regulation of rectal motility in rats.

INTRODUCTION: The colon and rectum are regulated by the autonomic nervous system (ANS). Abnormalities of the ANS are associated with diseases of the colon and rectum while its modulation is a putative mechanism for sacral nerve stimulation. The purpose of this study is to establish a rat model elucidating the role of the efferent ANS on rectal motility. MATERIALS AND METHODS: Rectal motility following transection or stimulation of parasympathetic pelvic nerves (PN) or sympathetic hypogastric nerves (HGN) was measured with rectal strain gauge transducers and quantified as a motility index (MI). Colonic transit was measured 24 hours after transection by calculating the geometric center (GC) of distribution of (51)Cr RESULTS AND DISCUSSION: Transection of PN and HGN decreased MI to 518 +/- 185 g*s (p < 0.05) and increased MI to 5,029 +/- 1,954 g*s (p < 0.05), respectively, compared to sham (975 +/- 243 g*s). Sectioning of PN and HGN decreased transit with GC = 4.9 +/- 0.2 (p < 0.05) and increased transit with GC = 8.1 +/- 0.7 (p < 0.02), respectively, compared to sham (GC = 5.8 +/- 0.3). Stimulation of PN and HGN increased MI to 831 +/- 157% (p < 0.01) and decreased MI to 251 +/- 24% (p < 0.05), respectively. CONCLUSION: Rectal motility is significantly altered by sectioning or stimulating either HGN or PN. This model may be useful in studying how sacral nerve stimulation exerts its effects and provide insight into the maladies of colonic motility.

Surgical management of intestinal malrotation in adults.

OBJECTIVE: The aim of this study was to review our experience with diagnosis and surgical management of intestinal malrotation in adult patients. PATIENTS AND METHODS: A retrospective review of the surgical outcome of adults with intestinal malrotation was performed. Twelve patients were observed and treated between July 1996 and July 2006 (4 women and 8 men; the mean age of the patients was 28.5 years). Surgical outcomes, including postoperative complications, deaths, and resolution of preoperative symptoms, were measured. RESULTS: A diagnosis of malrotation was made preoperatively in five patients by upper gastrointestinal contrast study, barium enema, or computed tomography scan. The anomaly was discovered incidentally at laparotomy in seven patients. All cases were proved to be malrotation intraoperatively. Nine patients underwent laparotomy and three underwent laparoscopic surgery (one converted to an open procedure). Follow-up ranged from 2 months to 118 months. Three patients had complications: one had wound infection, one had delayed gastric emptying, and one developed adhesive ileus. There were only two recurrences detected and one patient with recurrence required reoperation. No one died. CONCLUSIONS: Intestinal malrotation is a rare but important cause of abdominal pain in adults. It may present with chronic or acute symptoms. Laparotomy and laparoscopy are alternative and feasible techniques with low rates of complications for the treatment of intestinal malrotation in adults.

[Distribution and efficiency of recombinant adenovirus mediated human stem cell leukemia gene transfer in mice with interstitial cells of Cajal loss].

OBJECTIVE: To investigate the construction of the green fluorescent protein (GFP) labeled recombinant adenovirus containing human stem cell leukemia (hSCL) and its distribution and efficiency in mice with interstitial cells of Cajal (ICC) loss. METHODS: The recombinant adenovirus Ad-GFP/SCL was constructed by Ad-Easy system based on the homologous recombination in bacteria, then 1.6 x 10(9) PFU of recombinant adenoviruses were injected into Balb/c mice with ICC loss via the tail vein. In vivo distribution and efficiency of recombinant adenoviruses mediated hSCL were observed by GFP under the fluorescent microscope at different phases. The expression of SCL gene was measured by RT-PCR method. The damages were observed in different organs by HE staining. RESULTS: The recombinant adenovirus containing hSCL was quickly constructed by homologous recombination in bacteria using Ad-Easy system. Under the fluorescent microscope, GFP was revealed in heart, lung, liver, spleen, kidney, small intestine and large intestine of mice with ICC loss at different phases. No obvious damages were observed in various visceral organs by HE staining. RT-PCR showed SCL mRNA expression in various visceral organs at different levels. CONCLUSIONS: Construction of adenovirus vector by the homologous recombination in bacteria is an efficient and time saving method, and a high titer of adenovirus is able to mediate the safe and stable expression of SCL gene in mice with ICC loss. This finding will make further gene therapy in mice with STC possible.

[Effects of p53 inhibitor-alpha on the proliferation and apoptosis in large intestinal epithelial cells damaged by hyperthermic chemotherapy].

OBJECTIVE: To investigate the effects of p-fifty three inhibitor-alpha (PFT-alpha), a p53 inhibitor, on the proliferation and apoptosis of colon epithelial cells damaged by hyperthermic chemotherapy. METHODS: Normal epithelial cells were obtained from the mucosa at least 10 cm away from the cancer tissue in a specimen of large intestine cancer resected during operation and cultured. PFT-alpha at different concentrations was added into the culture fluid to observe its effects on the proliferation of the epithelial cells. Epithelial cell in logarithmic growth phase were inoculated in 6-well plate and divided into 3 groups: normal control (CON) group; hyperthermic chemotherapy (HTC) group, undergoing treatment of cisplatin and bath in water at 43 degrees C; and PFT-alpha + HTC group, undergoing treatment of PFT-alpha at different concentrations, cisplatin, and warm water bath. The cell apoptosis was observed by annexin V-fluorescein isothiocyanate/propidium iodide (PI) staining and flow cytometry (FCT). The cell cycle was observed by PI staining and FCT. Western blotting was used to detect the protein expression of cyclinB1 and Cdc2, and RT-PCR was used to detect the mRNA expression of cyclinB1. RESULTS: PFT-alpha at the concentration > 60 micromol/L significantly inhibited the proliferation of the large intestine epithelial cells. The natural apoptosis rate of the large intestine epithelial cells (CON group) was 2.9% +/- 0.4%, the apoptosis rate was 27.0% +/- 2.1% in the HTC group, and the apoptosis rates of the PFT-alpha + HTC group were 14.8% +/- 1.5%, 9.7% +/- 1.2%, 6.1% +/- 1.3%, and 3.8% +/- 0.3%, on a downward trend, corresponding to the increase of PFT-alpha concentration from 0, 20, 30, to 40 micromol/L (all P < 0.05). The G(0)/G(1) phase rate of epithelial cells was higher and the S phase rate was lower significantly in the PFT-alpha + HTC group. The G(2)/M phase rate was higher since the PFT-alpha concentration reached 10 micromol/L and then increased along with the increase of the PFT-alpha concentration; the S phase rates of the PFT-alpha + HTC group with different PFT-alpha concentrations were all significantly higher than that of the HTC group (all P < 0.01), however, were still lower than that of the CON group (all P < 0.01). The protein expressions of cyclinB1 and Cdc2 in the PFT-alpha + HTC group were both significantly higher than those in the CON and HTC groups (all P < 0.01), without a significant difference between the latter 2 groups. The mRNA expression of cyclinB1 in the PFT-alpha + HTC group increased along with the increase of the PFT-alpha concentration, and there wee significant differences in the mRNA expression of cyclinB1 between the CON and PFT groups and PFT-alpha + HTC group with the PFT-alpha concentration > or = 10 micromol/L (P < 0.05 or P < 0.01). CONCLUSION: PFT-alpha dose-dependently protects the hyperthermic chemotherapy-induced damage to the large intestine epithelial cells via upregulation of protein and mRNA expression of cyclinB1, increasing the phosphorylation level of Cdc2, decreasing the cyclinB1/Cdc2 activity, and increasing the G(2)/M phase rate of the cells.

Role of pelvicography and colpocystodefecography in diagnosis of outlet obstructive constipation.

AIMS: The aim was to research the changes in pelvic floor morphology and corresponding visceras in patients with outlet obstructive constipation (OOC). PATIENTS AND METHODS: Thirty-eight patients with OOC and 12 healthy volunteers were enrolled in this study. With simultaneous pelvicography and colpocystodefecography (PCCD), including pelvicography, vaginal opacification, voiding cystography and defecography, pelvic floor morphology was observed and the anorectal angle, the level of the perineum, peritoneum and bladder were measured. RESULTS: Thirty-seven cases of internal rectal prolapse (IRP), 5 cases of rectocele (RC) and 5 cases of spastic pelvic floor syndrome SPFS were diagnosed by PCCD. 12 IRP, 4 RC and 1 SPFS were detected by common physical examination. All of these were confirmed by PCCD. Moreover, PCCD found 9 pelvic floor hernia or peritoneoceles, 6 cystoceles, 3 descending perineum syndromes and 10 uterine prolapses. Compared with controls, OOC patients had a significantly large anorectal angle during defecation, abnormal descending of the perineum at rest and during defecation, and a deep pouch of Douglas during defecation. Some patients with urinary system symptoms may have had an abnormal descent of the bladder during rest and defecation. CONCLUSION: Simultaneous PCCD has a higher positive ratio than the common physical examination in diagnosing IRP and RC, and provides information for the diagnosis of pelvic floor hernia or peritoneocele, cystocele or uterine prolapse. PCCD is helpful in the selection of a proper surgical procedure.

Expression of c-kit messenger ribonucleic acid and c-kit protein in sigmoid colon of patients with slow transit constipation.

BACKGROUND AND AIMS: The c-kit protooncogene receptor and its ligand stem cell factor regulate the proliferation and survival of germ cells as well as interstitial cells of Cajal (ICCs). Decreased numbers of ICCs and defects in its networks have been reported in the colon of patients with slow transit constipation (STC). However, little information about the c-kit messenger ribonucleic acid (mRNA) and protein expression in the constipated colon is available. The aim of this study was to determine whether the expression of c-kit mRNA and c-kit protein declined in the colon in STC. PATIENTS AND METHODS: The sigmoid colonic samples from 12 patients with STC and from eight age-matched patients with non-obstructed colorectal cancer were used for this study. Expression of c-kit mRNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR), and expression of c-kit protein was detected by Western blot analysis. RESULTS: Decreased expression of c-kit mRNA was demonstrated in the STC group compared with the control group. The ratio of c-kit and beta-actin was 1.26+/-0.32 in controls and 1.17+/-0.41 in the STC group (U=0.500, P=0.029). c-kit protein expression significantly declined in the STC group. The mean value of optical density was 162.97+/-5.43 in the control group and 96.64+/-8.80 in the STC group (U=0.000, P=0.021). CONCLUSIONS: The data indicate that the expression of c-kit mRNA and c-kit protein significantly decreased in the colon of STC, suggesting that the c-kit signal pathway may play an important role in ICC reduction in STC.

[Study on distribution of interstitial cells of Cajal in the sigmoid colon of patients with slow transit constipation].

OBJECTIVE: Slow transit constipation (STC) is a colonic motor disorder whose etiology remains unclear. Recent studies have demonstrated a crucial role for interstitial cells of Cajal (ICC) in regulation of intestinal motility. The aim of this study was to examine the distribution of ICC within the normal sigmoid colon and STC patients. METHODS: Twelve patients with STC and eight age-matched controls were studied. ICC were identified with a monoclonal antibody to c-kit by an indirect immunofluorescence method. Immunostained tissues were examined with a laser scanning confocal microscope and the area occupied by ICC was calculated with image analysis software. RESULTS: ICC were located in the external muscle layers including longitudinal muscle (LM), myenteric plexus (MP), circular muscle (CM) and submucosal border (SMB). Two types of Kit-positive ICC were observed: bipolar cells characterized by one or two long processes, and multipolar cells with long stellate processes extending in various directions. A higher percentage of ICC was present in the MP regions and CM layers compared with the SMB and LM layers. Tissues from STC patients showed considerably decreased in number of ICC located in the four regions (ICC-LM, ICC-MP, ICC-CM, ICC-SMP), especially for ICC-SMP, almost completely disappeared. CONCLUSION: Decreased c-kit + ICC in number may play an important role in the pathophysiology of STC. It remains to be determined whether loss of ICC is primary or secondary to another lesion.

Decreased interstitial cells of Cajal in the sigmoid colon of patients with slow transit constipation.

BACKGROUND AND AIMS: Slow transit constipation (STC) is a colonic motor disorder that is characterized by measurably delayed movement of materials through the colon. Although abnormalities in the neuronal networks of the colon have been demonstrated in patients with STC, the etiology of STC remains unclear. Interstitial cells of Cajal (ICC) have been shown to be the pacemaker cells of the intestine and have been implied in the pathogenesis of a number of gastrointestinal motility dysfunctions, including idiopathic STC. This study aimed to determine the normal distribution of ICC within the colon of the Chinese and also to determine if ICC are decreased in Chinese STC patients. PATIENTS AND METHODS: Twelve patients with STC and eight age-matched normal controls were studied. Specimens of sigmoid colon were obtained immediately after resection. ICC were identified with a monoclonal antibody to c-kit by an indirect immunofluorescence method. Immunostained tissues were examined with a laser scanning confocal microscope and the area occupied by ICC was calculated with an image analysis system. RESULTS: ICC were located in the external muscle layers including myenteric plexus (MP) and submucosal border (SMB). Two types of Kit-positive ICC were observed: bipolar cells characterized by one or two long processes and multipolar cells characterized by long stellate processes extending in various directions. A higher percentage of ICC was present in the MP regions and circular muscle (CM) layers compared with the SMB and longitudinal muscle (LM) layers. Tissues from STC patients showed a considerable decrease in the number of ICC located in the four regions (ICC-LM, ICC-MP, ICC-CM, ICC-SMB), especially the ICC-SMB, in which ICC almost completely disappeared. CONCLUSIONS: Similar distribution of ICC was observed in the normal sigmoid colon of the Chinese. Decreased area of c-kit+ ICC may play an important role in the pathophysiology of STC. It remains to be determined whether the loss of ICC is primary or secondary to another lesion.