Search results for "absorption."
showing 10 items of 2682 documents
Carnitine transport into muscular cells. inhibition of transport and cell growth by mildronate
2000
Carnitine is involved in the transfer of fatty acids across mitochondrial membranes. Carnitine is found in dairy and meat products, but is also biosynthesized from lysine and methionine via a process that, in rat, takes place essentially in the liver. After intestinal absorption or hepatic biosynthesis, carnitine is transferred to organs whose metabolism is dependent on fatty acid oxidation, such as heart and skeletal muscle. In skeletal muscle, carnitine concentration was found to be 50 times higher than in the plasma, implicating an active transport system for carnitine. In this study, we characterized this transport in isolated rat myotubes, established mouse C2C12 myoblastic cells, and …
Steatocrit test after a standard fatty meal: A new simple and sensitive test to detect malabsorption
1991
The steatocrit test, a simple semiquantitative method for determining fat content in stool, was performed after a standard fatty meal to detect malabsorption in patients with celiac disease. Thirty-seven children (mean age 2.6 +/- 2.1 years) with total atrophy of the intestinal villi and 79 controls (mean age 3.5 +/- 2.8 years) were studied. All subjects underwent a small-bowel biopsy, a D-xylose absorption test, a rapid triglyceride absorption test, and a steatocrit determination first on an uncontrolled diet and then again after a standard fatty meal. The steatocrit test after a fatty meal did not detect any false-positive or false-negative results, while the D-xylose test showed two fals…
Coeliac disease: Oral ulcer prevalence, assessment of risk and association with gluten-free diet in children.
2008
Aims. Oral mucosal lesions may be markers of chronic gastrointestinal disorders, such as those causing malabsorption. Our objectives were to assess the prevalence of recurrent oral aphthous-like ulcers in coeliac disease patients living in the Mediterranean area, and to evaluate the impact of a gluten-free diet. Methods. A test group of 269 patients (age range 3-17 years) with coeliac disease confirmed both serologically and histologically was compared with a control group of 575 otherwise clinically healthy subjects for the presence, or a positive history of aphthous-like ulcers. Coeliac disease patients with aphthous-like ulcers were re-evaluated 1-year after starting a gluten-free diet. …
Bioavailability of nevirapine in rats after oral and subcutaneous administration, in vivo absorption from gastrointestinal segments and effect of bil…
2011
Abstract Nevirapine is a non-nucleoside reverse transcriptase inhibitor of human immunodeficiency virus type-1. The usual dosing regimen is 200 mg twice/day. Reducing the dosing frequency would significantly improve treatment adherence and quality of life of patients. To study new forms of administration, it is necessary to do pre-clinical studies and know the absorption characteristics of nevirapine in laboratory animals. However, there are no studies about its bioavailability in rats and hardly any about its pharmacokinetic. The objectives of this study were to describe the pharmacokinetics of nevirapine in rats after intravenous, oral and subcutaneous administration, to assess its absorp…
Pancreatic dysfunction and its association with fat malabsorption in HIV infected children
1998
Background—Nutrient malabsorption frequently occurs in HIV infected children, but very few studies have investigated exocrine pancreatic digestive capacity in these cases.Aims—To investigate pancreatic function in HIV infected children and to determine whether faecal fat loss, a prominent feature of intestinal dysfunction, is associated with pancreatic dysfunction.Patients—Forty seven children with HIV infection without apparent pancreatic disease and 45 sex and age matched healthy controls.Methods—Pancreatic function was evaluated by measuring elastase 1 concentration and chymotrypsin activity in stools by ELISA and colorimetric methods, respectively. Intestinal function was evaluated by m…
Immunologic and absorptive tests in celiac disease: can they replace intestinal biopsies?
1993
The sensitivity and specificity of several immunologic and absorption tests were determined in infants with celiac disease (31 male, 39 female; median age, 2.6 years) in different phases of the disease and in a group of control subjects with chronic diarrhea of different etiologies (32 male, 28 female; median age, 1.2 years). Intestinal biopsy was performed both in the patients and in the controls as a 'gold standard' for the diagnosis. The anti-gliadin antibody (AGA) IgG values showed a sensitivity of 89% and a specificity of 47%; AGA IgA were 69% sensitive and 92% specific; anti-endomysial antibodies (EmA) were 100% sensitive and 97% specific; the xylose test was 71% sensitive and 53% spe…
Parenteral nutrition improves nutritional status, autonomic symptoms and quality of life in transthyretin amyloid polyneuropathy
2016
Transthyretin familial amyloid polyneuropathy (TTR-FAP) is an inherited amyloidosis, leading to death in about ten years in most cases due to cardiac failure or wasting syndrome. Previous studies showed that modified body mass index was related to time before death, duration of gastrointestinal disturbances, malabsorption and functional capacity. We report two patients in whom nutritional status worsened despite diet modification, hypercaloric supplement and two relevant therapeutic approaches such as liver transplant and tafamidis meglumine, respectively. The first patient, a 52-year-old lady carrying Thr49Ala mutation, had a disease duration of twelve years and had lost weight up to 35 kg…
D-Glucose and fluid reabsorption in proximal surface tubule of the rat kidney
1972
Hexose reabsorption in the kidney was investigated by microperfusion of proximal cortical rat nephrons with Ringer's solution containingD-glucose (2.5, 5.0 and 18.0 mM/l), 3-O-methylD-glucose (4.5 mM/l) orD-fructose (18.0 mM/l) at perfusion rates of 20 or 40×10−6 ml/min. Inulin was used as a reference for fluid reabsorption. 1. The fraction of fluid reabsorbed was independent of the glucose concentration but it decreased when the perfusion rate increased from 20–40×10−6 ml/min. 2. At 18.0 mM/l the % glucose reabsorption was equal to the % fluid reabsorption. This equality was independent of the perfusion rate, (20 or 40×10−6 ml/min), indicating 1:1 coupling with net isotonic fluid reabsorpt…
Time course of development of transtubular sodium concentration differences in proximal surface tubules of the rat kidney. Micropuncture experiments …
1969
Int the proximal and distal surface tubules isotonic Na reabsorption (Φ Naout) is impaired by adrenalectomy. In the present experiments the time course of development of transtubular Na concentration differences (Na)P−(Na)TF was studied in the proximal convolution. 1. Na concentration was measured in free flow mannitol diuresis. Endproximal (Na)P−(Na)TF averaged 23.0±0.5 meq/l after 8.5±0.6 sec (controls) and 15.2±1.7 meq/l after 13.6±0.5 sec (adrenalectomized rats). 2. In modified stopped flow experiments tubular fluid, aspirated at the beginning of the proximal convolution in mannitol diuresis, was injected between two oil columnes and reaspirated after 28–36 sec of contact time. (Na)P−(N…
Partition of oleic acid between the lymph and portal blood in rats having a diverted bile–pancreatic duct
1996
AbstractThe present study examines the suggestion that in the absence of adequate bile and pancreatic juice, which support the absorption from the gut of long-chain fatty acidsinto lymph, the fatty acids are absorbed directly into the portal blood. Oleic acid (18:l) partitioning between lymph and portal blood was investigated in intact and bile- and pancreatic juice-diverted rats. In a first set of experiments, 18: 1 absorption from the gut into lymph and blood was studied by continuous recovery of the mesenteric lymph for 6 h and mesenteric portal venous blood for 1 h. In a second set of experiments, esterification processes were investigated by study of the mucosal distribution of labelle…