International Journal of Environmental Research and Public Health, 2019
The health benefits of dietary amylase resistant starch (RS) arise from intestinal microbial ferm... more The health benefits of dietary amylase resistant starch (RS) arise from intestinal microbial fermentation and generation of short chain fatty acids (SCFA). We compared the intestinal fermentative capability of stunted and nonstunted (‘healthy’) children in southern India using two types of RS: high amylose maize starch (HAMS) and acetylated HAMS (HAMSA). Twenty children (10 stunted and 10 healthy) aged 2 to 5 years were fed biscuits containing HAMS (10 g/day) for two weeks followed by a 2-week washout and then HAMSA biscuits (10 g/day) for 2 weeks. Fecal samples were collected at 3-4 day intervals and pH and SCFA analyzed. At entry, stunted children had lower SCFA concentrations compared to healthy children. Both types of RS led to a significant decrease in fecal pH and increase in fecal acetate and propionate in both healthy and stunted children. However, while HAMS increased fecal butyrate in both groups of children, HAMSA increased butyrate in healthy but not stunted children. Fu...
American Journal of Physiology-Gastrointestinal and Liver Physiology, 1994
Surfactant-like particles (SLP) have been isolated from the apical surface of rat enterocytes but... more Surfactant-like particles (SLP) have been isolated from the apical surface of rat enterocytes but appear to arise within the enterocyte and to be secreted into neighboring lymphatics (K. DeSchryver-Kecskemeti, R. Eliakim, S. Carroll, W. F. Stenson, M. A. Moxley, and D. H. Alpers. J. Clin. Invest. 84: 1355-1361, 1989). The present study was undertaken to analyze the clearance and distribution of these particle-associated proteins in vivo in the rat. Labeling of particles isolated from apical scrapings of rat enterocytes with 125I enabled identification of proteins of 116, 92, 68, 58, 48, 31, and 25 kDa. After the intravenous administration of 125I-SLP, the trichloroacetic acid-precipitable radioactivity in the plasma disappeared in a biphasic pattern. The average half-life of the early phase was 7.5 min and the second phase was 75 min. The half-life of a subset of the proteins (116, 92, and 48 kDa) was shorter, measuring 4.5 min for the first phase and ranging from 20 to 52 min for t...
American Journal of Physiology-Gastrointestinal and Liver Physiology, 1990
Rat intestinal alkaline phosphatase (IAP) is unique among the brush-border membrane enzymes in th... more Rat intestinal alkaline phosphatase (IAP) is unique among the brush-border membrane enzymes in that it is released bidirectionally (lumen and blood) and exists in either soluble (serum) or particulate (cellular) form. To elucidate the mechanism of membrane release, we examined the effects of phosphatidylinositol-specific phospholipase C (PtdIns-PLC) and serum anchor-specific phospholipase D (PLD) on the solubility of the various tissue forms of IAP. The "solubility" of cytosol IAP could be explained in part by intracellular PtdIns-PLC activity, detected by production of acidic IAP isomers, and by ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA)-sensitive PtdIns hydrolysis. Contamination with serum (abundant with anchor-specific PLD) was responsible for the complete or partial solubilization of IAP that was found during processing of light mucosal scrapings. Anchor-specific PLD activity was increased after fat feeding, and the IAP release...
American Journal of Physiology-Gastrointestinal and Liver Physiology, 1992
The rat enterocyte produces a particle with surfactant-like properties (including a whorled appea... more The rat enterocyte produces a particle with surfactant-like properties (including a whorled appearance, enrichment for dipalmitoyl phosphatidylcholine, and ability to lower surface tension) that also is enriched for intestinal alkaline phosphatase. Human Caco-2 cells grown on polycarbonate filters were utilized to study the secretion of these particles and exhibited whorls and strands of unilamellar membranes, particularly concentrated at the apical pole or near junctional complexes. Concentrated culture medium from these cells separated on continuous NaBr gradients revealed a fraction at density = 1.07 g/l enriched for phosphatidylcholine and intestinal alkaline phosphatase. This fraction contained membranous sheets containing alkaline phosphatase, detected by immunolocalization. Phosphatidylcholine comprised 54% of phospholipid in this fraction, compared with 20% in brush borders. When Caco-2 cells were transfected with cDNA encoding rat intestinal alkaline phosphatase, cellular p...
Gastric parietal cells have been accepted as the only site of intrinsic factor production in the ... more Gastric parietal cells have been accepted as the only site of intrinsic factor production in the human stomach. In animals, however, intrinsic factor has been localised to various other cell types of foregut origin, including chief and enteroendocrine cells in gastric mucosa, and duct cells from salivary glands and pancreas. The availability of recombinant human intrinsic factor has led to production of high titre, monospecific antiserum which was used to reexamine the distribution and subcellular localisation of intrinsic factor in the human stomach. Immunolight microscopy revealed that most positively stained cells were gastric parietal cells, but at the margins of the anatomical regions (e.g. cardia/fundus, body/antrum) clusters of gastric chief cells and individual enteroendocrine cells were found to contain intrinsic factor. Immunoelectron microscopy demonstrated the highest antigen density on endocytic and apical membranes of parietal cells. Exocrine secretory granules of a su...
... products. Fruits and vegetables have very little or no cobalamins, and hence vegans and other... more ... products. Fruits and vegetables have very little or no cobalamins, and hence vegans and other strict vegetarians proba-bly derive their limited intake from foods or water contaminated with microorganisms contained in manure. ...
JAMA: The Journal of the American Medical Association, 1971
Dr. Kent Kreisman, Senior Assistant Resident, Jewish Hospital of St. Louis and Assistant in Medic... more Dr. Kent Kreisman, Senior Assistant Resident, Jewish Hospital of St. Louis and Assistant in Medicine, Washington University School of Medicine: A 34-year-old woman was admitted for evaluation of diarrhea. This symptom first began in 1956, and consisted of four to five loose, watery, and occasionally bloody stools daily. The patient continued to have intermittent episodes of diarrhea over the subsequent four years, and in 1960, a diagnosis of ulcerative colitis was made. In 1964, the patient was admitted to another hospital and the terminal 4 feet of ileum, ascending colon, and half of the transverse colon were resected. The remaining distal portion of the ileum was anastomosed to the distal transverse colon. Numerous fistulae were found at the time of surgery and a diagnosis of "regional enteritis" was made. Following surgery, her weight, which had been 45.4 kg (100 lb), fell to 22.7 kg (50 lb). It subsequently returned to
International Journal of Environmental Research and Public Health, 2019
The health benefits of dietary amylase resistant starch (RS) arise from intestinal microbial ferm... more The health benefits of dietary amylase resistant starch (RS) arise from intestinal microbial fermentation and generation of short chain fatty acids (SCFA). We compared the intestinal fermentative capability of stunted and nonstunted (‘healthy’) children in southern India using two types of RS: high amylose maize starch (HAMS) and acetylated HAMS (HAMSA). Twenty children (10 stunted and 10 healthy) aged 2 to 5 years were fed biscuits containing HAMS (10 g/day) for two weeks followed by a 2-week washout and then HAMSA biscuits (10 g/day) for 2 weeks. Fecal samples were collected at 3-4 day intervals and pH and SCFA analyzed. At entry, stunted children had lower SCFA concentrations compared to healthy children. Both types of RS led to a significant decrease in fecal pH and increase in fecal acetate and propionate in both healthy and stunted children. However, while HAMS increased fecal butyrate in both groups of children, HAMSA increased butyrate in healthy but not stunted children. Fu...
American Journal of Physiology-Gastrointestinal and Liver Physiology, 1994
Surfactant-like particles (SLP) have been isolated from the apical surface of rat enterocytes but... more Surfactant-like particles (SLP) have been isolated from the apical surface of rat enterocytes but appear to arise within the enterocyte and to be secreted into neighboring lymphatics (K. DeSchryver-Kecskemeti, R. Eliakim, S. Carroll, W. F. Stenson, M. A. Moxley, and D. H. Alpers. J. Clin. Invest. 84: 1355-1361, 1989). The present study was undertaken to analyze the clearance and distribution of these particle-associated proteins in vivo in the rat. Labeling of particles isolated from apical scrapings of rat enterocytes with 125I enabled identification of proteins of 116, 92, 68, 58, 48, 31, and 25 kDa. After the intravenous administration of 125I-SLP, the trichloroacetic acid-precipitable radioactivity in the plasma disappeared in a biphasic pattern. The average half-life of the early phase was 7.5 min and the second phase was 75 min. The half-life of a subset of the proteins (116, 92, and 48 kDa) was shorter, measuring 4.5 min for the first phase and ranging from 20 to 52 min for t...
American Journal of Physiology-Gastrointestinal and Liver Physiology, 1990
Rat intestinal alkaline phosphatase (IAP) is unique among the brush-border membrane enzymes in th... more Rat intestinal alkaline phosphatase (IAP) is unique among the brush-border membrane enzymes in that it is released bidirectionally (lumen and blood) and exists in either soluble (serum) or particulate (cellular) form. To elucidate the mechanism of membrane release, we examined the effects of phosphatidylinositol-specific phospholipase C (PtdIns-PLC) and serum anchor-specific phospholipase D (PLD) on the solubility of the various tissue forms of IAP. The "solubility" of cytosol IAP could be explained in part by intracellular PtdIns-PLC activity, detected by production of acidic IAP isomers, and by ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA)-sensitive PtdIns hydrolysis. Contamination with serum (abundant with anchor-specific PLD) was responsible for the complete or partial solubilization of IAP that was found during processing of light mucosal scrapings. Anchor-specific PLD activity was increased after fat feeding, and the IAP release...
American Journal of Physiology-Gastrointestinal and Liver Physiology, 1992
The rat enterocyte produces a particle with surfactant-like properties (including a whorled appea... more The rat enterocyte produces a particle with surfactant-like properties (including a whorled appearance, enrichment for dipalmitoyl phosphatidylcholine, and ability to lower surface tension) that also is enriched for intestinal alkaline phosphatase. Human Caco-2 cells grown on polycarbonate filters were utilized to study the secretion of these particles and exhibited whorls and strands of unilamellar membranes, particularly concentrated at the apical pole or near junctional complexes. Concentrated culture medium from these cells separated on continuous NaBr gradients revealed a fraction at density = 1.07 g/l enriched for phosphatidylcholine and intestinal alkaline phosphatase. This fraction contained membranous sheets containing alkaline phosphatase, detected by immunolocalization. Phosphatidylcholine comprised 54% of phospholipid in this fraction, compared with 20% in brush borders. When Caco-2 cells were transfected with cDNA encoding rat intestinal alkaline phosphatase, cellular p...
Gastric parietal cells have been accepted as the only site of intrinsic factor production in the ... more Gastric parietal cells have been accepted as the only site of intrinsic factor production in the human stomach. In animals, however, intrinsic factor has been localised to various other cell types of foregut origin, including chief and enteroendocrine cells in gastric mucosa, and duct cells from salivary glands and pancreas. The availability of recombinant human intrinsic factor has led to production of high titre, monospecific antiserum which was used to reexamine the distribution and subcellular localisation of intrinsic factor in the human stomach. Immunolight microscopy revealed that most positively stained cells were gastric parietal cells, but at the margins of the anatomical regions (e.g. cardia/fundus, body/antrum) clusters of gastric chief cells and individual enteroendocrine cells were found to contain intrinsic factor. Immunoelectron microscopy demonstrated the highest antigen density on endocytic and apical membranes of parietal cells. Exocrine secretory granules of a su...
... products. Fruits and vegetables have very little or no cobalamins, and hence vegans and other... more ... products. Fruits and vegetables have very little or no cobalamins, and hence vegans and other strict vegetarians proba-bly derive their limited intake from foods or water contaminated with microorganisms contained in manure. ...
JAMA: The Journal of the American Medical Association, 1971
Dr. Kent Kreisman, Senior Assistant Resident, Jewish Hospital of St. Louis and Assistant in Medic... more Dr. Kent Kreisman, Senior Assistant Resident, Jewish Hospital of St. Louis and Assistant in Medicine, Washington University School of Medicine: A 34-year-old woman was admitted for evaluation of diarrhea. This symptom first began in 1956, and consisted of four to five loose, watery, and occasionally bloody stools daily. The patient continued to have intermittent episodes of diarrhea over the subsequent four years, and in 1960, a diagnosis of ulcerative colitis was made. In 1964, the patient was admitted to another hospital and the terminal 4 feet of ileum, ascending colon, and half of the transverse colon were resected. The remaining distal portion of the ileum was anastomosed to the distal transverse colon. Numerous fistulae were found at the time of surgery and a diagnosis of "regional enteritis" was made. Following surgery, her weight, which had been 45.4 kg (100 lb), fell to 22.7 kg (50 lb). It subsequently returned to
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