膳食纤维促短肠大鼠结肠代偿

目的探讨加用膳食纤维的肠内营养(EN)对短肠大鼠结肠代偿的促进作用.方法制作切除80%～85%的短肠大鼠模型,用Pepti-2000做EN治疗,同时加用膳食纤维(EF),观察其全身营养状况和结肠形态学的改变.结果术后15 d起EF组体重增加,并于第18 d起明显优于EN组(P＜0.05),第9天EN组正氮平衡明显低于CONT组(P＜0.001),而EF组与CONT组无差异.EF组结肠壁厚度、粘膜厚度、绒毛高度和绒毛表面积均比CONT和EN组有极为显著的差异(P＜0.01).结肠粘膜细胞DNA指数,EN和EF组均明显高于CONT组(P＜0.05),且S期细胞百分比均明显高于CONT组(P＜0.05).各实验组IGF-1mRNA含量均比CONT组有极显著差异(P＜0.01).EF组血胰岛素和胰高糖素明显高于CONT组(P＜0.05).结论应用膳食纤维治疗的短肠大鼠全身营养状况及结肠形态学代偿明显优于单用肠内营养组.     

Dietary fiber

Much has been written about dietary fiber in the past decade in both medical and popular journals. The possibility of improving our health and preventing certain diseases by eating more fiber is appealing. In this article, Dr Handler thoroughly explores the evidence relating fiber deficiency to various colonic diseases. Two of our reviewers, while recommending publication, felt that the article overstates the case for the relationship. Our readers will, of course, judge for themselves whether they find the evidence persuasive.     

The use of fluorography in the diagnosis of tumors of the large intestine

A current approach to the perfection of the diagnosis of colonic tumors is proposed in patients at risk by means of introduction into the ambulatory health care system (polyclinics, diagnostic centers) of standardized colonic fluorography followed by endoscopy in necessary cases. The main organizational and methodological principles of the use of colonic fluorography were worked out as a method of screening to reveal colonic tumors. It is suggested that such new elements as the "prescopic stage" realized outside the radiation zone, automated distant air inflation into the colon and so forth may be introduced in colonic fluorographic examination. Experience gained with over 2065 colonic fluorographies on a special fluorograph and 1120 examinations on routine x-ray diagnostic units fitted with the amplifier and a photochannel (79 cases of colonic carcinoma and 89 benign tumors were identified) evidences that the program of making colonic fluorography enables one to significantly improve the diagnosis of colonic tumors.     

Diet in Benign Colonic Disorders: A Narrative Review

PurposeDiet plays an important role in common benign colorectal diseases. This article reviews the evidence for diet and supplemental fiber in patients with chronic constipation, irritable bowel syndrome, inflammatory bowel disease, colonic diverticulitis, and fecal incontinence.MethodsWe performed a narrative review of the evidence for diet and supplemental fiber in patients with 5 common benign colonic diseases and summarized guideline recommendations for each condition. We generated tables of practical dietary advice by disease.FindingsDiet advice must be individualized and depends on underlying conditions, disease severity, symptom burden, and nutrition status. Guidance from a registered dietitian is highly recommended when making any dietary changes. Data from trials suggest that soluble fiber is effective for patients with chronic constipation, irritable bowel syndrome, and fecal incontinence. A diet low in select fermentable, oligo-, di-, and monosaccharides, and polyols may benefit patients with irritable bowel syndrome. Patients with inflammatory bowel disease, especially those with active disease, are at risk for malnutrition. Dietary restrictions may further increase that risk. There is limited evidence to recommend increasing or avoiding select food groups in patients with inflammatory bowel disease. Patients who have recovered from diverticulitis should adopt a prudent dietary pattern high in fruits, vegetables, whole grains, legumes, poultry, and fish.ImplicationsClinicians should counsel patients on the contribution of diet to their colorectal condition and the benefits and harms of dietary modification. Dietary advice should be practical and accompanied by realistic expectations for benefit.     

Les fibres sont-elles toutes des pr��biotiques ?

A first part refers to the present knowledge regarding the colonic microflora with a special focus on its composition, the key element of its physiological functions. Based on these elements, the notion of ??colonic food?? is proposed as a new dimension to be taken into account when formulating nutritional recommendations. The concepts of ??dietary fiber?? and ??prebiotic?? are then introduced and defined underlying on the one hand what they do have in common but on the other hand, and more importantly, what makes them different and specific. In conclusion a motivated answer to the title question is given.     

Effects of pectin on diarrhea in critically ill tube-fed patients receiving antibiotics.

BACKGROUND: Anaerobic colonic flora are necessary for the fermentation of fiber into short-chain fatty acids and constitute the bulk of fecal mass. Lack of dietary fiber in most enteral feedings, compounded by antibiotic therapy, suppresses normal colonic metabolism, resulting in diarrhea. Pectin, a water-soluble fiber, stimulates epithelial growth in the colon and thus reduces diarrhea. METHODS: Forty-four critically ill patients receiving enteral nutrition and antibiotic therapy were randomized to receive fiber-containing or fiber-free tube feedings and pectin or placebo. Data on frequency, consistency, and volume of fecal output; energy (caloric) intake; and administration of specific medications were collected for 9 days. Diarrhea was defined as 2 or more days with scores of 12 or higher on the Hart and Dobb diarrhea scale. RESULTS: Subjects in the 4 groups did not differ significantly in age, sex, severity of illness, or energy intake. Twelve subjects (27.3%) experienced diarrhea. Significantly fewer subjects in the fiber-free/placebo and fiber/pectin groups experienced diarrhea than did subjects in the fiber/placebo group (P = .02). On the basis of repeated-measures analysis of variance of daily mean scores, the severity of diarrhea did not differ significantly among the study groups over time (P = .16). CONCLUSIONS: The reduced rate of diarrhea found in this study may be related to the stringent definition of diarrhea used. The therapeutic dose of pectin for reducing diarrhea needs further exploration. The trend was toward less diarrhea in the fiber/pectin group, but the study needs to be replicated with a larger sample.     

Polyps in the colon. Answers to key questions.

Adenomatous polyps in the adult colon and rectum are of great clinical importance because they can undergo malignant degeneration. Size and histologic type are useful in predicting the likelihood of malignancy. In most cases, biopsy is required to distinguish small adenomas (< 1 cm) from hyperplastic polyps, which do not undergo malignant degeneration. An adenomatous polyp found during proctosigmoidoscopy warrants total colonoscopy with polypectomy, because of the possibility of a synchronous adenoma or cancer. Periodic colonoscopic follow-up is advised, because of the high rate of recurrent ("metachronous") adenomas. The optimal screening technique for colorectal polyps and early cancer in the general population remains to be defined. The most commonly used program at present entails periodic fecal occult blood testing and flexible proctosigmoidoscopy. Diets high in fiber and low in fat may have protective effects against the development of colonic neoplasms.     

Atlas-based fiber reconstruction from diffusion tensor MRI data

Purpose

Develop a neural fiber reconstruction method based on diffusion tensor imaging, which is not as sensitive to user-defined regions of interest as streamline tractography.

Methods

A simulated annealing approach is employed to find a non-rigid transformation to map a fiber bundle from a fiber atlas to another fiber bundle, which minimizes a specific energy functional. The energy functional describes how well the transformed fiber bundle fits the patient??s diffusion tensor data.

Results

The feasibility of the method is demonstrated on a diffusion tensor software phantom. We analyze the behavior of the algorithm with respect to image noise and number of iterations. First results on the datasets of patients are presented.

Conclusions

The described method maps fiber bundles based on diffusion tensor data and shows high robustness to image noise. Future developments of the method should help simplify inter-subject comparisons of fiber bundles.     

Pharmacologic characterization of the muscularis mucosae in three regions of the rabbit colon.

The aim of the present in vitro study was to provide information on the pharmacologic properties of the muscularis mucosae in three regions of the rabbit colon. Proximal muscularis mucosae exhibited spontaneous contractions whose frequency was independent of endogenous acetylcholine. In the mid and distal colon, spontaneous contractile frequencies were depressed by atropine and enhanced by eserine. Muscularis mucosae from all regions responded to acetylcholine, ADP, AMP, ATP, bradykinin, histamine, methoxamine, substance P, vasoactive intestinal polypeptide but not cholecystokinin octapeptide or gamma-aminobutyric acid. Low concentrations of norepinephrine caused propranolol-sensitive relaxations of proximal colonic muscularis mucosae whereas high concentrations evoked phentolamine-sensitive contractions. In the mid and distal colon, norepinephrine caused relaxations which were poorly antagonized by propranolol. Proximal colonic muscularis mucosae responded to electrical stimulation with an atropine- and tetrodotoxin-sensitive "on contraction." Responses from the mid and distal colon were tetrodotoxin-sensitive and consisted of an atropine-sensitive "duration contraction" followed by a propranolol-insensitive "off relaxation" which was not mediated by prostaglandin synthesis, a purine, or vasoactive intestinal polypeptide. These data suggest that the rabbit colonic muscularis mucosae possesses alpha-1 adrenoceptors, histamine H1, muscarinic, P2 purinoceptors and beta adrenoceptors. However, their relative importance and the nature of the intrinsic innervation suggests considerable specialization of this muscle layer in different regions of the rabbit colon.     

The end of the diet debates? All fats and carbs are not created equal

The key to healthy eating is choosing "good fats"--foods high in omega-3 fatty acids and unsaturated fats, and "good carbohydrates"--foods high in fiber and having a low glycemic index. The healthiest diet is the Mediterranean type, consisting of lean meats, fish, nuts, vegetables, whole fruits, and whole grains.     

Constipation

Most patients with chronic constipation respond to dietary measures, fiber supplements, or laxatives. For those who do not, diagnostic tests of colonic and anorectal function help to select appropriate treatments. Therapeutic options, pharmacologic agents, and surgery, the last resort, are discussed in this article.     

Preparation for colonoscopy using Golytely--a sure method? Comparative histological and clinical study between lavage and saline laxatives

Looking at clinical side-effects, effectiveness and tolerability, we compared the salinic solution "Golytely" vs. a conventional preparatory procedure (Cascara-Salax) in a prospective study including 28 patients with macroscopic normal mucosa. Mucosal changes in colonic step biopsies were investigated according to prefixed criteria. Results: There was no significant difference concerning weight, blood pressure, pulse rate, body temperature or essential laboratory findings. Whereas preparation using Cascara-Salax was less molesting stated by the patients, there was no difference in the way colonoscopy itself was tolerated in both groups. The performing doctor's evaluation of the colonic cleaning effect and examination conditions showed "Golytely" significantly ahead of Cascara-Salax. Histologically, colonic mucous layers depicted changes in the control groups in 63% vs. 40% in the "Golytely" group. "Golytely" seems to provide a safe and effective method of preparation for colonoscopy.     

活动期溃疡性结肠炎患者结肠黏膜中生长抑素受体的表达及其临床意义

目的:研究生长抑素受体(somatostatin receptor,SSTR)在活动期溃疡性结肠炎(ulcerative colitis,UC)中的表达及其临床意义.方法:取36份活动期UC患者的结肠黏膜标本(结肠炎组)及30份体检者的结肠黏膜标本(对照组),采用免疫组织化学法检测两组SSTR的表达情况.结果:SSTR的表达主要定位于结肠黏膜的上皮细胞、纤维细胞、淋巴细胞和小血管的内皮细胞的细胞质中.SSTR在UC结肠黏膜中的阳性表达率为92%,明显高于对照组的73%(P＜0.05).中、重度UC患者结肠黏膜SSTR的阳性表达率均明显高于轻度UC患者(均为P＜0.05).便血明显(肉眼可见)的UC患者结肠黏膜SSTR的阳性表达率明显高于便血不明显(肉眼不可见,但潜血试验阳性)的UC患者(P＜0.05).结论:活动期UC患者结肠黏膜的SSTR的表达上调,其上调程度在病情较重或伴明显便血患者中更高.     

肠镜下高频电息肉切除术的应用及护理

目的探讨肠镜下高频电息肉切除术的应用及护理方法。方法对196例内镜下高频电息肉切除术患者资料进行回顾性分析。结果196例患者在医护人员双方的共同配合下顺利进行手术操作，平均操作时间6min，无明显并发症发生。结论内镜下高频电息肉切除术安全有效，通过采取规范的护理措施能够增强手术效果，提高手术质量。     

High-resolution colonic manometry and its clinical application in patients with colonic dysmotility: A review

The detailed process and mechanism of colonic motility are still unclear, and colonic motility disorders are associated with numerous clinical diseases. Colonic manometry is considered to the most direct means of evaluating colonic peristalsis. Colonic manometry has been studied for more than 30 years; however, the long duration of the examination, high risk of catheterization, huge amount of real-time data, strict catheter sterilization, and high cost of disposable equipment restrict its wide application in clinical practice. Recently, high-resolution colonic manometry (HRCM) has rapidly developed into a major technique for obtaining more effective information involved in the physiology and/or pathophysiology of colonic contractile activity in colonic dysmotility patients. This review focuses on colonic motility, manometry, operation, and motor patterns, and the clinical application of HRCM. Furthermore, the limitations, future directions, and potential usefulness of HRCM in the evaluation of clinical treatment effects are also discussed.     

Detection of colonic inflammation with Fourier transform infrared spectroscopy using a flexible silver halide fiber

Persistent colonic inflammation increases risk for cancer, but mucosal appearance on conventional endoscopy correlates poorly with histology. Here we demonstrate the use of a flexible silver halide fiber to collect mid-infrared absorption spectra and an interval model to distinguish colitis from normal mucosa in dextran sulfate sodium treated mice. The spectral regime between 950 and 1800 cm(-1) was collected from excised colonic specimens and compared with histology. Our model identified 3 sub-ranges that optimize the classification results, and the performance for detecting inflammation resulted in a sensitivity, specificity, accuracy, and positive predictive value of 92%, 88%, 90%, and 88%, respectively.     

Low-attenuation oral GI contrast agents in abdominal-pelvic computed tomography

Background We designed and evaluated a low-attenuation oral contrast agent for abdominal-pelvic computed tomography (CT). Methods In vitro studies, were performed initially to evaluate the imaging characteristics of multiple solutions. These studies resulted in two solutions being compared with the presently accepted oral CT agents of dilute iodinated contrast and water. Ninety-eight consecutive subjects already scheduled for routine outpatient abdominal-pelvic CT were enrolled. Subjects were randomized to water (n = 30), fiber solution (n = 32), polyethylene glycol (PEG; n = 11), or dilute iodinated solution (DI; n = 25). Examinations were then evaluated for gastric distention, small bowel distention, small bowel wall visualization, and colonic transit. A questionnaire was given to the study subjects for feedback concerning taste and potential side effects from these agents. Results PEG tended to provide better bowel distention, wall visualization, and colonic transit compared with water, fiber solution, and DI. Areas of statistical significance included: (1) average bowel diameter in the left upper quadrant for water was 17.50 mm, whereas that for PEG was 21.88 mm (p < 0.05); (2) average bowel diameter in the pelvis for water was 14.79 mm, that for fiber was 15.67 mm, and that for PEG was 18.48 mm (p < 0.05); (3) wall visualization was better with PEG than with fiber (p < 0.05); (4) successful transit of contrast to the colon occurred in every subject who received PEG compared with only 20% of those received water and 39% of those who received fiber (p < 0.05). Similar trends for the superiority of PEG over DI were noted, although many of these did not reach statistical significance. Conclusion PEG solution has imaging characteristics related to bowel wall visualization, luminal distention, and colonic transit that make it an effective oral agent for abdominal pelvic CT examination.     

Tales from the crypt

Intestinal colonic crypts are derived from a stem cell population located at the base of each crypt. A new analysis of mitochondrial function and of the rates of mitochondrial DNA (mtDNA) mutation in individual crypts shows that mtDNA mutations arise in stem cells - and at a surprisingly high frequency. Because crypts turn over extremely rapidly (about once per week), somatic mtDNA mutations can "take over the system" and even become homoplasmic, in a manner similar to what has been shown to occur in tumors.     

3L生理氯化钠联合螺纹管在急性左半结肠梗阻术中结肠灌洗护理配合

目的探讨3L生理氯化钠联合螺纹管在急性左半结肠梗阻术中结肠灌洗护理的效果。方法选择2012年3月~2014年3月我院治疗的因结肠肿瘤造成急性肠梗阻进行腹腔探查患者30例作为A组。选择2010年3月~2012年3月我院治疗的因结肠肿瘤造成急性肠梗阻患者30例作为B组。A组采用螺纹管配合的微创灌洗方法。B组采用传统的灌洗方法。两组清理术野、腹腔,关闭腹腔的方法均相同。比较两组术后吻合口瘘发生率、腹腔感染、切口感染发生率。结果A组吻合口瘘、腹腔感染、切口感染率发生率明显低于B组(P0.05)。结论 3L生理氯化钠联合螺纹管在急性左半结肠梗阻术中结肠灌洗护理配合效果优于传统的开放肠腔进行冲洗护理配合方式。