bluuebunny/crossref_metadata_2025_split huggingface dataset:
Depressed Gut Absorptive Capacity Early After Trauma‐Hemorrhagic Shock G. SINGH, K. I. CHAUDRY, L. C. CHUDLER, AND I. H. CHAUDRY Annals of Surgery 214:712–718, 1991
Authors: Nussbaum Michael S. 
Published: May 2008

The authors investigated the effect of the calcium channel antagonist diltiazem on gut absorptive capacity after hemorrhage in rats. Carotid and femoral arterial catheters, portal and jugular venous catheters, and nasogastric tubes were placed in 12 anesthetized animals. After recovery from the anesthetic, eight animals (groups 2 and 3) were bled via the femoral catheter to a mean arterial pressure (MAP) of 40 mm Hg. This level of hypotension was maintained by continued bleeding to the maximal bleedout volume (approximately 60% of the animal's circulating blood volume), followed by infusion of lactated Ringer's solution until 40% of the maximal bleedout volume had been returned. The animals were then resuscitated with lactated Ringer's solution. Four rats (group 1) were not hemorrhaged and served as sham controls. During resuscitation the animals in group 2 received an additional 1 mL of saline, whereas those in group 3 were treated with diltiazem 400 μg/kg body weight in 1 mL of saline. MAP was measured throughout the experiment. Portal and central venous pressures were measured at the onset of hemorrhage, maximal bleedout, end of hemorrhage, end of resuscitation, and just before the D‐xylose absorption tests. Gut absorptive, capacity was determined using the 1‐hour D‐xylose absorption test at 2 hours and 4 hours after the end of hemorrhage. The D‐xylose was administered via the nasogastric tubes; portal blood was sampled 1 hour later and assayed for D‐xylose.The animals treated with diltiazem had a significantly lower MAP 2 hours after the end of hemorrhage, whereas at 4 hours, both hemorrhaged groups were significantly lower than controls. Central venous and portal pressures were significantly lower in the hemorrhaged groups at maximal bleedout and end of hemorrhage compared with the sham‐operated animals. However, these values returned to normal by 2 hours after the end of hemorrhage. There were no differences in the venous pressures between the animals receiving saline or diltiazem. The saline‐treated animals' gut absorptive capacity as measured by D‐xylose absorption was significantly reduced at 2 and 4 hours after the end of hemorrhage. Diltiazem administration restored gut absorptive capacity to normal at both time points after the end of hemorrhage.
Clinical and Metabolic Efficacy of Glutamine‐ Supplemented Parenteral Nutrition After Bone Marrow Transplantation. A Randomized, Double‐Blind, Controlled Study T. R. ZIEGLER, L. S. YOUNG, K. BENFELL, ET AL Annals of Internal Medicine 116:821–828, 1992
Authors: Sax Harry C. 
Published: May 2008

Glutamine (GLN), long considered to be a nonessential amino acid, may be conditionally essential during periods of metabolic stress.1 It has been suggested that the improved results seen in patients given enteral, as opposed to parenteral, nutrition may in part be due to the provision of GLN. Commercial amino acid solutions do not contain GLN because of its inherent instability. Glutamine‐supplemented solutions are currently under investigation and may be of benefit to patients who cannot tolerate enteral feedings. Bone marrow transplantation is one such setting, where the combination of radiation and chemotherapy make enteral support untenable.Forty‐five patients underwent allogeneic bone marrow transplantation for hematologic malignancies. They were randomly assigned to receive either a standard glutamine‐free total parenteral nutrition solution or one supplemented with L‐glutamine to provide 0.57 g of GLN/ kg per day in a blinded fashion. Overall protein intake was 1.5 g/kg per day. Patients were allowed to eat ad libitum, but they consumed fewer than 300 calories daily. Total parenteral nutrition was discontinued when patients were able to consume 50% of their needs orally daily for 3 consecutive days.All patients survived their acute hospitalization. One hundred‐day survival was not different between the two groups. The GLN group had significantly fewer clinical infections than did the control group. Ten of 24 GLN patients completed their hospitalization with no positive cultures as opposed to 1 of 21 control patients (p <.01). The majority of positive cultures in the control group were for Candida albicans.Daily nitrogen balance data were available in those patients not being treated with corticosteroids for graftvs‐host disease. During the early phase of transplantation (days 4 to 11), average daily nitrogen balance remained more negative in the control group (—4.2 ± 1.2 vs ‐1.4 ± 0.5 g; p <.002). There was no statistically significant difference between the two groups from days 18 to 25.Total days of parenteral support were equal in both groups. However, total hospital days were significantly fewer in the GLN group, most likely because of the decreased incidence of septic complications.
Upregulation of Nutrient Transport in Fetal Rabbit Intestine by Transamniotic Substrate Administration
Authors: Sax Harry C. 
Published: May 2008

Intrauterine growth retardation complicates 3% to 7% of full‐term pregnancies. The developing fetal gastrointestinal tract has the ability to absorb nutrients delivered via the amniotic sac. It is not clear, however, if this nutrient delivery does in fact aid in promoting additional maturation and development of the fetal gut. Sixteen pregnant New Zealand White rabbits underwent celiotomy on gestational day 24. The bicornuate uterus was exposed, and the ovarian‐end fetuses were randomly assigned to either a control or a study group. A catheter was placed in the amniotic cavity in each side of the uterus for nutrient infusion and was secured in place. Both catheters were exteriorized; animals were partially restrained but were allowed free access to food and water. Immediately postoperatively, infusion of either a metabolizable carbohydrate (d‐galactose; experimental group) or a nonmetabolized, nontransported carbohydrate (mannitol; control group) was carried out. Six days later, each fetus was harvested. A segment of intestinal sleeve was inverted, and uptakes of radiolabeled glucose and galactose were determined in proximal, middle, and distal segments of the small intestine.No significant differences were noted in fetal body weight or fetal small intestinal length between control and experimental groups. Mucosal weight, expressed as percent of total small intestinal weight, was significantly greater only in the proximal intestinal segment in the experimental group when compared with the control group.Mucosal galactose uptake (nmol/mg of protein per minute) for each intestinal segment was determined and significant increases were noted in the experimental group, in the middle and distal segments, when compared with the control group. However, no significant differences between the two groups were noted when galactose uptake was expressed in nmol/cm per minute. Mucosal glucose uptake (nmol/mg per minute) was significantly increased in the proximal and distal segments, but not in the middle segment, of the small intestine. Again, the differences in glucose uptake between the two groups were not statistically significant when expressed as nmol/cm per minute. Nutrient uptake, calculated for the entire small intestine, was significantly greater (p <.05) in the experimental group compared with the control group.The authors concluded that the developing fetal rabbit is capable of upregulating its intestinal mucosal brush border transport in response to administration of galactose in the amniotic fluid.
Marked Resistance of Normal Subjects to Tube‐Feeding‐Induced Diarrhea: The Role of Magnesium H. E. KANDIL, F. H. OPER, B. R. SWITZER, ET AL American Journal of Clinical Nutrition 57:73–80, 1993
Authors: Heimburger Douglas C. 
Published: May 2008

Because it is often assumed that feeding formulas are responsible for the diarrhea that commonly occurs in tube‐fed patients, the authors of this report sought to test the tolerance in normal subjects of a commonly used enteral feeding formula. They reasoned that if normal persons can tolerate substantial volumes of feeding without diarrhea, it may be patient‐specific factors and not the formulas themselves that cause diarrhea in sick persons. After five healthy male volunteers had undergone a 72‐hour acclimation to oral Ensure Plus (Ross Laboratories, Columbus, OH), the investigators administered Osmolite HN (Ross Laboratories) by continuous duodenal infusion, at progressively increasing infusion rates, until the subjects could no longer tolerate it.The subjects were able to tolerate maximum infusion rates of between 198 and 340 mL/h (5000 to 8650 kcal/ d). In two subjects, the infusion was stopped for symptoms other than diarrhea (abdominal distention, bloating, heartburn, and headache in one, and abdominal distention with vomiting in the other). These subjects never developed diarrhea, defined as >300 g of stool per day, despite maximum infusion rates of 371 and 258 mL/ h. The diarrhea that developed in the other three subjects was modest (350 to 380 g/d) and occurred only at infusion rates exceeding 275 mL/h, or more than 400% of their estimated basal energy expenditures.Blood and stool samples were analyzed to elucidate the mechanisms causing the diarrhea. The magnesium content of pooled diarrheal stools was significantly greater than that of nondiarrheal stools, suggesting that the magnesium load (mean 89 mmol/24 h, or more than 6 times the typical intake for US men) may have been the causal factor. There was no evidence that unabsorbed fat, carbohydrate, or protein contributed to the diarrhea.
Effect of Total Parenteral Nutrition on Amino Acid and Glucose Transport by the Human Small Intestine
Authors: Sax Harry 
Published: May 2008

The perioperative use of total parenteral nutrition (TPN) as an adjunct to surgical treatment of severely nutrient‐depleted patients is appropriate. Potentially deleterious effects of TPN on the gut have been examined with regard to atrophy and gut mucosal barrier function.1 The specific alterations in nutrient transport, an energy‐dependent luminal mechanism, have not, however, been clearly defined. Active transport of specific amino acids across the brush‐border membrane is facilitated by a number of carriers, some of which are sodium dependent.2 The maintenance of a sodium gradient requires energy; it is hypothesized that down‐regulation of brush‐border membrane transport should result from periods of low availability of luminal nutrients. If specific nutrients are physiologically more important, transport would be maintained.To study these changes, adult patients who were to undergo intestinal surgery were randomized to immediate operation or a 7‐day period of bowel rest with calorie and protein needs met by TPN. At celiotomy, segments of distal ileum were obtained and mucosa scraped for the preparation of brush‐border membrane vesicles. The brush‐border membrane vesicles were coincubated with labeled amino acids in the presence or absence of sodium. By determining the time course of uptake into vesicles, the maximum velocity as well as the affinity of the specific receptor can be determined. By expressing this data as an Eadie‐Hofstee transformation, the number of receptor sites can be extrapolated. Specific nutrients examined included glutamine (GLN), methyl‐d‐amino isobutyric acid (a system A analog), alanine, arganine, and glucose.A period of no oral nutrition, even with adequate parenteral nutrition support, caused down‐regulation in the number of receptors for alanine, arginine, leucine, and glucose. GLN transport, however, was maintained. In a single patient in whom jejunum was available, nutrient uptake was decreased across the board; however, GLN was the least diminished.
Arginine Stimulates Wound Healing and Immune Function in Elderly Human Beings S. J. KIRK, M. HLRSON, M. C. REGAN, ET AL Surgery 114:155–160. 1993
Authors: Sax Harry C. 
Published: May 2008

With the aging of the population, a larger number of elderly patients are undergoing more complex surgical procedures. In addition to advanced age, the general decline in metabolic reserve may lead to an increased risk of perioperative complications in these patients. Furthermore, their specialized nutritional needs remain unclear. Arginine, a semiessential amino acid, has been shown to enhance T‐cell‐mediated immune function both in healthy animals and in humans.1,2 The use of a specialized enteral feeding with supplemental arginine as well as with omega‐3 fatty acids and nucleotides significantly reduced complications and hospital stays in a series of patients undergoing upper gastrointestinal tract surgery for cancer.3To study the effects of supplemental arginine on wound healing in an elderly but otherwise healthy group of patients, 45 patients were randomly assigned to receive 30 g of arginine (as a syrup) per day or no supplemental arginine (control group) for a total of 2 weeks. Immune function was measured by lymphocyte response to well known mitogens such as phytohemagglutinin, concanavalin A, or poke weed. Mixed‐lymphocyte culture quantified the response to alloantigens by noting the increase in thymidine uptake in the lymphocytes of the patients when they were exposed to other human lymphocytes. Wound healing was examined both as the deposition of hydroxyproline into a subcutaneously implanted polytetrafluoroethylene catheter and as the creation of a partial‐thickness wound on the anterior aspect of the thigh. The wound was then observed and photographed daily until re‐epithelialization had taken place.All patients tolerated arginine supplementation without notable gastrointestinal tract dysfunction. There was a significant increase in serum insulin‐like growth factor (IGF‐I) levels (203 ± 18 ng/mL vs 140 ng/mL; p <.04). This is consistent with the role of arginine as a potent pituitary secretogogue. Arginine supplementation further increased collagen deposition into subcutaneous catheters as reflected by increased levels of hydroxyproline (17.4 ± 2 nmol/cm; p <.02). Despite this, there was no increase in the rate of epithelialization of the skin defect (12.5 days). The blastogenic effects of mitogens were significantly increased in all groups from day 1 through day 14. The increases in thymidine incorporation ranged from 15% to 80% for mitogens, with a 300% increase in the mixed‐lymphocyte response.
The Metabolism of [75Se]Selenite in Patients With Short Bowel Syndrome
Authors: Rannem Terje , Hylander Ellinor , Ladefoged Karin , Staun Michael , Tjellesen Lone , Jarnum Stig 
Published: May 2008

BackgroundPatients on home parenteral nutrition (HPN) require significantly higher amounts of selenium compared with controls. The purpose of the present study was to investigate if selenium deficiency of patients with short bowel syndrome is caused by selenium malabsorption or by excessive intestinal or renal loss.MethodsThe metabolism of [75Se]selenite was investigated in eight selenium‐depleted short bowel patients on HPN and in six control subjects. The isotope was given orally, and in a subsequent study as bolus injection or as 12‐hour IV infusion.ResultsThe fractional intestinal absorption of selenium was significantly reduced in the patients (2% to 58%, median 20%) when compared with the reference group (79% to 91%, median 82%) (p < .001). Within the group of patients we found a positive significant correlation between fractional selenium absorption and the length of the remaining small intestine (r = 0.95, p < .05). After parenteral [75Se]selenite administration, the patients showed a significantly higher fecal loss and a significantly reduced urinary excretion of 75Se when compared with the controls. Bolus injection vs 12‐hour infusion of [75Se]selenite did not affect the cumulative fecal or urinary 75Se excretion in the HPN patients.ConclusionsReduced intestinal selenium absorption is probably the most important cause of the selenium deficiency reported in patients with short bowel syndrome, but increased endogenous intestinal selenium loss and low selenium intake may also contribute. Despite the renal counterregulation, which results in a low urinary selenium excretion, HPN patients need a supply of selenium with their parenteral nutrition.
Nutrition Support in Clinical Practice: Review of Published Data and Recommendations for Future Research Directions
Authors: Klein Samuel , Kinney John , Jeejeebhoy Khursheed , Alpers David , Hellerstein Mark , Murray Michael , Twomey Patrick 
Published: May 2008

In the last 30 years, marked advances in enteral feeding techniques, venous access, and enteral and parenteral nutrient formulations have made it possible to provide nutrition support to almost all patients. Despite the abundant medical literature and widespread use of nutritional therapy, many areas of nutrition support remain controversial. Therefore, the leadership at the National Institutes of Health, The American Society for Parenteral and Enteral Nutrition, and The American Society for Clinical Nutrition convened an advisory committee to perform a critical review of the current medical literature evaluating the clinical use of nutrition support; the goal was to assess our current body of knowledge and to identify the issues that deserve further investigation. The panel was divided into five groups to evaluate the following areas: nutrition assessment, nutrition support in patients with gastrointestinal diseases, nutrition support in wasting diseases, nutrition support in critically ill patients, and perioperative nutrition support. The findings from each group are summarized in this report.This document is not meant to establish practice guidelines for nutrition support. The use of nutritional therapy requires a careful integration of data from pertinent clinical trials, clinical expertise in the illness or injury being treated, clinical expertise in nutritional therapy, and input from the patient and his/her family. (Journal of Parenteral and Enteral Nutrition21:133–156, 1997)
Enhanced Growth of Small Bowel in Transgenic Mice Expressing Human Insulin‐Like Growth Factor
Authors: Ney Denise M. 
Published: May 2008

Insulin‐like growth factor 1 (IGF‐1) plays an important role in the regulation of intestinal growth and maturation, whereas the direct effects of growth hormone (GH) on intestinal growth are less clear. In this study the authors utilize a transgenic mouse model to assess the extent to which longterm excess of IGF‐1 in a background of GH deficiency stimulates small bowel growth.IGF‐1 transgenic mice that overexpress an IGF‐1 transgene driven by the mouse metallothionein I promotor were compared with wild‐type littermates and GH transgenic mice. The IGF‐1 transgenics showed elevation of circulating IGF‐1, undetectable levels of plasma GH, and a decrease in pituitary GH messenger RNA (mRNA) caused by negative feedback effects of IGF‐1 excess. Growth of small bowel, abundance and localization of mRNAs for the IGF‐1 transgene, and IGF binding protein 3 (IGFBP‐3) were assayed to determine whether enterotrophic effects of excess IGF‐1 correlate with local overexpression of IGF‐1 in small bowel.Small bowel length and mass were greater in IGF‐1 transgenic than in wild‐type mice. Villus height, crypt depth, and crypt cell mitoses were greater in IGF‐1 transgenics than wild‐type mice. Jejunal dissacharidase activities were not different among the IGF‐1 transgenics and wild‐type mice. The IGF‐1 transgene was expressed strongly in villus epithelial cells and at much lower, but significant levels in crypt epithelial cells, lamina propria, and smooth muscle layers. IGFBP‐3 was strongly expressed and localized in the lamina propria.Regional expression of IGF‐1 and IGFBP‐3 correlated with the increase in mucosal mass in IGF‐I transgenics.Effects of IGF‐I overexpression on intestinal length and mucosal mass were similar to effects of GH overexpression, although IGF‐I transgenics showed greater small bowel growth relative to somatic growth compared with GH transgenics. Excess of IGF‐I increased crypt cell proliferation, whereas excess of GH did not increase crypt cell proliferation but did stimulate jejunal sucrase activity. These observations suggest that GH has greater differentiative actions, whereas IGF‐I exerts primarily mitogenic actions in small bowel.
Student Preferences for Adaptations in Classroom Testing
Authors: Nelson Janet S. , Jayanthi Madhavi , Epstein Michael H. , Bursuck William D. 
Published: May 2008

The purpose of the present study was to investigate student preferences for specific adaptations in general education classroom testing. Participants in the study were 158 middle school students, including students with high-incidence disabilities (HID) and general education students with low, average, high, and very high achievement. Students completed an instrument developed for the study, the Student Preferences for Testing Adaptations Questionnaire. Students rated each of 23 specific testing adaptations on a 4-point scale (1 = dislike to 4 = high preference). In two additional questions, students also stated reasons for a single most-liked and a single least-liked adaptation. Most testing adaptations were at least moderately preferred by students. Open-notes and open-book tests were among the adaptations most preferred, and least-preferred adaptations included teacher reading of test questions to students and tests with fewer questions or covering less material. Students with HID and/or students with low achievement indicated significantly higher preference than did students with average or above-average achievement for several adaptations. Students' rationales for their choices of most-liked adaptations included improved test performance as well as the opportunity to work with peers and to receive assistance. On the other hand, students' descriptions of least-liked adaptations included concerns regarding fairness and interference with their own style of working.