The effect of arginine supplementation on growth hormone release and intestinal mucosal growth after massive small bowel resection in growing rats

Four-week-old male Sprague-Dawley rats underwent a 90% small bowel resection. From the fourth day after surgery, they were divided into group 1 and 2, and pair-fed by elemental diets (0.8 kcal/mL, 50 mL/day) with L-arginine (n = 10) or L-glycine (n = 11) as an isonitrogenous and isoenergetic supplement for 3 weeks. They were compared with each other 3 weeks after surgery. A statistical analysis was performed using the unpaired Student's t test and the one-way factorial analysis of variance (ANOVA) using Bonferroni/Dunn multiple comparison test. A Pvalue of < .05 was considered significant. There were no significant differences between the two groups in food intake, body weight, tail length, residual ileal length, and plasma IGF-I level. However, the mean height of ileal villi in group 1 showed higher than that in group 2 (P < .01). Growth hormone-releasing hormone (GHRH) provocative tests (1 microg per rat, intravenously) showed the more significant elevation of growth hormone IGH) secretion in the arginine supplement group than that of glycine supplement group at 5 minutes (P < .05). There were no significant differences between basal levels of plasma rat GH in both groups. It is suggested that arginine has a possible significant role of GH secretion and intestinal mucosal growth after massive small bowel resection.     

Nutritional implications of significant small bowel resection

Nutrition support of the patient with short bowel syndrome is determined by the extent and location of bowel resection, the functional status of residual bowel, and presence or absence of the ileocecal valve. The authors discuss the consequences and treatments for bowel resection.     

Effect of ageing on pancreatic hyperplasia after 90% proximal small bowel resection

PURPOSE: A longitudinal study to ascertain the attitudes toward, and habits of, substance use among a single class of medical students. METHOD: A single class from a northeastern medical school was surveyed in both its first year (February 1991, 176 students) and its third year (May 1993, 170 students). The students were asked to report how frequently during the prior year they had used drugs or alcohol, and whether their use of each substance had increased, decreased, or remained the same since entering medical school; to identify any family members with histories of alcohol or drug problems; and to report any incidence during the prior year of ten behaviors associated with substance dependence. The students were also asked to indicate their agreement or disagreement with 11 attitudinal statements. Additional attitudinal items asked the students to identify three major deterrents to the abuse of drugs and alcohol, and what they had done if they had become aware of a classmate with a drug or alcohol problem. Chi-square analysis and two-tailed t-tests were used to compare data from the two surveys. RESULTS: The response rates in the first and second surveys were 96.9% and 81.8%, respectively. Use of licit and illicit substances was comparable to that of chronological peers and prior national studies of medical trainees. Most of the students admitted to using alcohol at least once in the prior year (91.8% and 95%, respectively). In both years marijuana was the illicit drug used most often. Although there was a slight increase over time in the use of benzodiazepines (2.4% to 5.8%) and a decrease in the use of marijuana (29.4% to 21.7%), these changes were not significant. Few of the students in their third year reported using any substance other than alcohol more than once a month. In general, a greater percentage of the students reported a decrease rather than an increase in the use of a substance since entering medical school; the primary exception was for wine. As they progressed in their training, the students became less concerned about the effect of substance use on their performance and more likely to be embarrassed about admitting to an addiction. Although in each year a few of the students appeared to be at risk for substance dependence (8.9% and 3.5%, respectively), no student came to the attention of the administration because of problems related to substance use. While most of the students were unaware of any classmate who had a problem, half of those who were aware had done nothing, and the balance had rarely sought assistance from the faculty or administration. CONCLUSION: Although there was no evidence that substance use was a major problem, a few of the students appeared to be at risk for drug or alcohol dependence. Appropriate intervention, support, and referral systems should be identified for the few who may be at risk, and increased educational efforts are needed to help all students address this issue with their peers and, ultimately, with their patients.     

Abnormalities in proximal small bowel motility in patients with cirrhosis

Replantation of right hindlimbs in 76 immature rats was performed to study the factors affecting longitudinal growth of replanted extremities. There was a significant difference in tibia length between the replanted limb and the contralateral normal limb. The difference was significantly influenced by the ischemic interval (2 vs 4 hours), but not by suture method (intact vessels, vascular anastomosis with 10-0 nylon or 11-0 nylon). The replantation of immature extremities should be promptly undertaken because of the vulnerability of the epiphysis to ischemic insult.     

Intestinal adaptation after extensive resection of the small intestine and prolonged administration of parenteral nutrition

After a superior mesenteric thrombosis in a 77 year old man, all but 24 centimeters of the jejunum were resected and anastomosed to the remaining left colon. After being maintained on parenteral nutrition on a 24 hour basis for six weeks, the patient was placed on overnight parenteral nutrition in which he received 2 liters of parenteral nutrition solution containing about 2,200 calories. Over a period of nine months, hypertrophy, lengthening and dilatation took place so that the patient was almost able to support himself by mouth. We believe that this is the first patient in whom documented lengthening of the small intestine has been reported. The factors entering into the hypertrophy and dilatation are discussed. Many patients in this age group are denied therapy because of the consequences of massive enterectomy. With adaptation using prolonged parenteral nutrition, it should be possible for most patients to sustain themselves completely by mouth. Patients with massive necrosis of the small intestine should not be denied therapy even if only 1 foot of small intestine remains. This is likely to hypertrophy in length until parenteral nutrition is no longer necessary.     

Orthotopic liver transplantation improves small bowel motility disorders in cirrhotic patients

Altered small intestinal motility has been observed in patients with liver cirrhosis. Its pathophysiology remains to be defined. Our aim was to investigate the effect of orthotopic liver transplantation on small intestinal dysmotility in patients with liver disease. Two patients were studied both before and after orthotopic liver transplantation. Abnormal migrating motor complex activity and prominent clustered contractions present preoperatively normalized within 6 months after the surgical procedure. This finding might represent an additional benefit of liver transplantation considering that altered motility may be involved in bacterial overgrowth and infections observed in these patients.     

Adaptation after small bowel resection is attenuated by sialoadenectomy: the role for endogenous epidermal growth factor

Reactive oxygen species generated during the metabolism of the antitumor quinone 3,6-diaziridinyl-1,4-benzoquinone (DZQ) in human colonic carcinoma HCT116 cells lead to the induction of p21 (WAF1, Cip1, or sdi1), an upstream regulator of the retinoblastoma gene product pRb involved G1 cell cycle control. We here demonstrate that the cell cycle was arrested in G2/M phase following supplementation with DZQ of human osteosarcoma Saos-2 cells (lacking both p53 and pRb) and HCT116 cells. DZQ also induced p21 and apoptosis in Saos-2 cells. The transfection of the Rb gene into Saos-2 cells did not alter the level of p21 induction, but changed cell cycle arrest into G1 phase and prevented apoptosis. These findings suggest that quinones may lead to a p53-independent and pRb-preventable G2/M arrest and apoptosis, which correlate with p21 induction.     

Different responses of apolipoprotein A-I, A-IV, and B gene expression during intestinal adaptation to a massive small bowel resection in rats

Gene expression of apolipoproteins (apo) A-I, A-IV, and B, the predominant protein components of chylomicrons, was investigated in the residual ileum after a massive small bowel resection in rats. A Northern blot analysis showed that the apo A-IV mRNA level, but not the apo A-I and B mRNA levels, in the ileum was significantly higher in the resected rats than in the sham-operated rats 24 h and 2 wk post-surgery. RT-PCR coupled with a primer extension assay revealed that the apo B-48 mRNA/apo B-100 mRNA ratio, i.e., apo B mRNA editing, in the ileum was unchanged by the resection. It is thus concluded that, among the major intestinal apolipoproteins, apo A-IV is the only one whose gene expression is influenced by loss of the proximal intestine.     

Nitric oxide-producing neurons remain intact after small bowel transplantation

This study documents the fate of nitric oxide neurons following small bowel transplantation. Heterotopic, syngeneic small bowel transplants were performed in five male Lewis rats. The grafts were harvested 7, 36, 55, 60, and 65 days postoperatively, together with the native bowel for comparison. NADPH diaphorase staining of cryostat sections was used to identify the nitric oxide-producing neurons. NADPH diaphorase activity was concentrated in the myenteric plexus, deep muscular, and submucous plexus. No differences were detected between the transplanted and native bowel at any time after transplantation. This suggests that nitric-oxide-producing neurons are well preserved after transplantation and that posttransplant dysmotility is probably not related to interrupted nitric oxide innervation.     

Long-term follow-up after bowel resection for necrotizing enterocolitis: factors affecting outcome

BACKGROUND: Necrotizing enterocolitis (NEC) is the most common surgical emergency among newborns and is associated with a high morbidity and mortality. This study evaluates the long-term survival of infants requiring surgical intervention for NEC and factors affecting outcome. METHODS: A retrospective review of infants requiring surgery for complications of NEC at a tertiary care, pediatric hospital over a 16-year period was performed. Patients were evaluated for early and late morbidity and mortality, length of intestinal resection, presence of the ileocecal valve (ICV), days of parenteral nutrition (PN), and growth. RESULTS: Two hundred forty-nine patients were included, with an average gestational age of 30 +/- 5 (+/- SD) weeks and birth weight of 1.50 +/- 0.89 kg. The surgical mortality rate was 45%, with survivors (137) being larger (P < .001) and older (P < .001) at time of birth than nonsurvivors. Mortality rates varied inversely with gestational age and birth weight. Surgical survivors had an average of 21 +/- 26 cm of intestinal length resected. The ileocecal valve was preserved in 45% of infants. Growth was similar between infants with or without an ICV. Stratification of length of intestine resected showed that infants with larger resections had greater requirements for parenteral nutrition, but this had no influence on long-term growth at follow-up. CONCLUSIONS: Survivors of NEC are characterized by greater gestational age, greater birth weight, and older postgestational age at surgery. Infants who underwent greater intestinal resections required longer periods of PN. The length of intestine resected or presence of the ileocecal valve had no overall bearing on long-term outcome.     

Propulsion and mixing of small bowel contents after laparotomy in rat

Radioactive test substances were infused slowly into the duodenum of conscious rats via a permanent catheter starting 2, 12 and 24 h after a standardized laparotomy. Two differently labelled but otherwise identical test substances were used. The first test substance (125I-PVP) was infused for 4 h, the second (131I-PVP) for the remaining 1 h of the 5-hour infusion period. Immediately after the infusion the animals were killed, and the radioactivity emanating from each isotope was recorded from the excised bowel specimen. The bowel length passed by the border zone and the degree of overlap between the labels in this zone were taken as measures of propulsion and mixing, respectively. Propulsion and mixing were uninfluenced by laparotomy as measured 2--17, 12--17 and 24--29 h after laparotomy. The present findings indicate that laparotomy is not followed by a disturbance in the capability of the small bowel to transport and mix chyme, at least when no high demands with respect to chyme volume are required.     

Host immune suppression after small bowel/liver transplantation in rats

Biopsy samples from seven patients with acquired immunodeficiency syndrome were screened for Mycoplasma fermentans, M. pneumoniae and M. genitalium infection by the polymerase chain reaction. M. fermentans DNA was detected in four patients. Various tissues were evaluated and the mycoplasma were mainly detected from lymph nodes. Moreover, mycoplasma genus-specific DNA was isolated from peripheral blood mononuclear cells of asymptomatic human immunodeficiency virus(HIV)-infected individuals (two of 31 HIV-infected individuals). These data suggest that mycoplasma infection in AIDS patients is not uncommon.