Time-dependent alteration of epidermal growth factor receptor in rat stomach by ethanol feeding

This study investigated the time-dependent effects of ethanol (EtOH) feeding on epidermal growth factor binding and epidermal growth factor-mediated functions in the stomach. Adult male rats were fed either an isocaloric control or EtOH-containing liquid diet (36% total calories as EtOH) for 2, 4 and 6 weeks. At the end of each feeding period, animals were sacrificed and the stomach was dissected for the sample preparation. EtOH caused a time-dependent alteration (r = 0.89) of the 125I-epidermal growth factor binding to the gastric mucosal membrane (% control: week 2, 114%; week 4, 64%* and week 6, 45%*, n = 5, *P < 0.05). Protein kinase analysis also showed that EtOH caused a time-dependent decrease of epidermal growth factor-stimulated autophosphorylation of epidermal growth factor receptor protein (180 kDa) during three feeding periods. Western blot analysis, using anti-tyrosine phosphorylated epidermal growth factor receptor (active form) antibody, revealed a major immunoreactive protein band (180 kDa) in all samples pre-incubated with 1 microM epidermal growth factor. Consistent with data from kinase analysis, treatment of EtOH decreased the immunoreactivity of the active form of epidermal growth factor receptor (180 kDa) in the stomach. In conclusion, EtOH feeding caused a time-dependent alteration of epidermal growth factor receptor in the stomach, which may be one of the mechanisms underlying the gastric pathology associated with alcohol abuse.     

The effect of dietary flaxseed supplementation on organic anion and osmolyte content and excretion in rat polycystic kidney disease

Progression of chronic renal failure in the Han:SPRD-cy rat polycystic kidney disease is associated with renal depletion of citric acid cycle metabolites and betaine. Amelioration of this disease by a soy protein diet is associated with retention of citric acid cycle anions, despite increased excretion, and preservation of tissue levels of betaine. As we have recently found that modest dietary supplementation with flaxseed preserves renal function and reduces histologic injury in the Han:SPRD-cy rat, we undertook a high-resolution 1H NMR spectroscopic study of urine and renal tissue extracts from Han:SPRD-cy rats to explore the renal biochemical consequences of a flaxseed diet. There was no significant dietary effect upon organic anion, methylamine, or osmolyte excretion in healthy animals. There was increased citrate excretion in Han:SPRD-cy rats fed flaxseed. Urinary ammonium excretion did not differ, suggesting that the observed increase in citrate excretion was not due to an alkaline effect of diet. Tissue extract studies revealed that disease amelioration was associated with tissue retention of succinate and betaine. Amelioration of Han:SPRD-cy rat polycystic kidney disease by diet is associated with alteration in the handling of citric acid cycle metabolites. Betaine may have a metabolic role in the reduction of chronic renal injury.     

High galactose levels in vitro and in vivo impair ascorbate regeneration and increase ascorbate-mediated glycation in cultured rat lens

In contrast to conventional view that glucose is the sole glycating agent, ascorbate has now emerged as a potential precursor of advanced glycation products in lenses during cataractogenesis, owing to the high concentration present in human lens. The effects of high hexose environment in vitro and in vivo on the disruption of redox equilibrium of ascorbate (ASA) to dehydroascorbate (DHA), which is required for ascorbate-mediated crystallin modification by the Maillard reaction during cataractogenesis were examined. Organ culture experiments were performed with rat lenses that were first exposed to high galactose levels in vitro and in vivo and then incubated with 1-14C-labeled ASA, DHA or DKG (2,3-diketogulonic acid). Formation of ASA degradation products as a function of time was assessed by radiometric TLC method. Upon incubation with ASA or DHA, an elevated level of the degradation product, DKG, was detected in lenses exposed to galactose in vivo and in vitro. ASA uptake was significantly enhanced in the galactosemic lenses as compared to controls (P = 0.01). Regeneration of ASA from DHA in both galactose treated and galactosemic lenses was impaired when compared to control lens which completely converted DHA from the medium into ASA. Surprisingly, the galactose exposed lenses showed enhanced permeability to DKG which was picked up readily from the medium in contrast to normal healthy lenses which remained impermeable to DKG. Galactose exposed lenses both in vitro and in vivo showed a 5-9-fold increase in crystallin bound Schiff base-linked radioactivity when incubated with 1-14C-labeled ASA or DHA. As a preamble to the question of whether lens pigmentation predisposes towards ascorbate oxidation, lens homogenate from normal young and old pigmented cataractous lenses were incubated with [1-14C]ASA. After 2 days, ASA levels were found to have decreased by 74% and DKG levels increased by 48% in brunescent lens as compared to the young lens. These data demonstrated that profound abnormalities in ASA metabolism exist in lenses exposed to a high sugar environment suggestive of a breakdown of the redox equilibrium of ASA to DHA and a loss of membrane permeability barrier for DKG. The latter would further contribute toward a ASA-catalysed Maillard reaction in the redox impaired lens.     

Circadian blood pressure changes in untreated children with kidney disease and conserved renal function

Ambulatory blood pressure monitoring over 24 h was applied in 31 children with kidney disease, aged 3-19 (median 11) years, in the absence of renal insufficiency and without antihypertensive therapy. Median creatinine clearance was 112 ml/min/1.73m2. Ambulatory blood pressure monitoring revealed that eight patients (26%) were hypertensive during the daytime, compared to 62% through casual recordings obtained in the office and 38% when blood pressure was taken at home. Nocturnal hypertension was detected by ambulatory monitoring in six patients, two of whom had normal blood pressure in the daytime. Median nocturnal dipping was 13% for systolic and 21% for diastolic blood pressure, i.e. similar to healthy children. Rhythm analysis recognized a distorted circadian pattern for systolic and/or diastolic blood pressure in eight patients. In conclusion, ambulatory blood pressure monitoring allows the evaluation of hypertension more reliably than casual recordings in the office. Nocturnal hypertension, as a major risk factor for renal deterioration, is detected in a similar proportion as daytime hypertension in almost 20% of untreated children with kidney disease and normal renal function.     

Biochemical and histological changes in blood, erythrocytes and tissue of rats on feeding Dryopteris juxtaposita fern

One tenet of successful orthodontic therapy is to complete treatment without decalcification, hypocalcification, or discoloration of the natural dentition. Fluoride application has been shown to reduce demineralization of enamel. The purpose of this study was to see if fluoride could be incorporated into enamel before orthodontic bracketing without adversely affecting bond strength. Forty extract adolescent human premolars were randomly divided into two equal groups with 20 teeth each. Group 1 served as control group, and group 2 (experimental) was immersed in 1.23% acidulated phosphate fluoride for 4 minutes after acid etching. The buccal surfaces of all 40 teeth were then bonded with the same type of metal bracket and debonded with an Instron machine. The debonding interface was observed with scanning electron microscopy (SEM). The mapping was calculated with energy dispersive x-ray spectrometry. The results showed that the bond strength of group 1 was significantly greater than that of group 2. The enamel detachment (enamel fracture) was found in the experimental group only. Although the application of acidulated phosphate fluoride to a tooth can prevent dental decay or decalcification, the bond strength decreases and enamel detachment is found after debonding. The result shows that the application of acidulated phosphate fluoride after acid etching enamel has an adverse effect on orthodontic bond strength of human enamel.     

N-Acetylgalactosamine 4,6-bissulfate in rat urine. II. Occurrence in rat cartilage and blood

The intraperitoneal injection of inorganic [35S]sulfate to rat was followed by the rapid appearance in urine of a labeled compound which behaved as N-acetylgalactosamine 4,6-bissulfate on paper chromatography and paper electrophoresis and when treated with two sulfatases with a high degree of specificity toward the sulfate bonds at positions 4 and 6, respectively. Enzymatically-prepared N-acetylgalactosamine 4,6-[6-35S]bissulfate was injected intravenously into rats. Of the injected dose, 90% was excreted unchanged in the urine during the subsequent 12 h, suggesting that the urinary N-acetylgalactosamine 4,6-bissulfate may derive from blood as renal filtrate. Examination of the rats injected with inorganic [35S]sulfate revealed the presence of labeled N-acetylgalactosamine 4,6-bissulfate at significant levels in the blood and cartilage, but at much lower levels in the liver. The cartilage component was highest in its rate of 35S uptake, suggesting that the blood component may derive at least in some part from the cartilage. Exposure of surviving cartilage slices to inorganic [35S]sulfate, followed by extraction of the slices with hot 50% ethanol yielded a number of radioactive compounds, of which three were characterized as UDP-N-acetylgalactosamine-4,6-[35S]bissulfate, N-acetylgalactosamine-1-phosphate 4,6-[35S]bissulfate and N-acetylgalactosamine 4,6-[35S]bissulfate. By subjecting the prelabeled tissue to chase incubation, it was possible to show that the UDP-N-acetylgalactosamine-4,6-bissulfate in the tissue disappeared with an approximate half-life of 10 min with a concomitant appearance in the medium of N-acetylgalactosamine 4,6-bissulfate and its 1-phosphate ester. These results suggest the occurrence in cartilage of an enzymatic system which is responsible for rapid turnover of UDP-N-acetylgalactosamine-4,6-bissulfate and possibly required for the rapid secretion of N-acetylgalactosamine 4,6-bissulfate into extracellular field.     

Determination of Ag ions in water, urine and blood

Isolated human polymorphonuclear leukocytes were submitted to long wave ultraviolet light (UVA) with and without preincubation of the cells with 8-methoxypsoralen (8-MOP). Leukocyte chemotaxis was determined in modified Boyden chambers using caseine as the attractant. Combined treatment (8-MOP + UVA) significantly inhibited the chemotactic activity with 8-MOP concentrations above 0.1 mug/ml and 2 J/cm(2). However, with high dosage of UVA (5 J/cm(2)) with and without 8-MOP still 25-30% cells migrated through the filters. Also, cell viability as determined by trypan blue exclusion was only moderately affected by combined treatment. The results indicate that these nonreplicating cells are comperatively insensitive to UVA and 8-MOP.     

Free lysine, glycine, alanine, glutamic acid and aspartic acid reduce the glycation of human lens proteins by galactose

The amino acids lysine, glycine, alanine, glutamate and aspartate formed adducts with galactose at physiological pH and temperature as shown by incorporation of U[14C] galactose. The percentage of galactose reacting with lysine, glycine, alanine, glutamate and aspartate was 4.5 to 7.8, 7.9 to 10.8, 3.2 to 4.6, 2.8 to 4.8 and 3 to 5.2, respectively. Studies with lysine showed that the extent of glycation of the free amino acid increased with time. Incubation of lens homogenate with galactose, effected glycation of proteins. Addition of lysine in concentrations of 5 and 10 mM to equimolar concentrations of galactose decreased the glycation of lens proteins by 64% to 71%; glycine, alanine, glutamate and aspartate decreased glycation by 23 to 68%, 32 to 61%, 35 to 56% and 26 to 61% respectively. Under similar conditions, glycine reacts to a greater extent than lysine, alanine, glutamic and aspartic acids. However, lysine was more effective than glycine, alanine, aspartic and glutamic acids in decreasing glycation of lens proteins by galactose. The decrease of glycation with added lysine increased with time. In general increase of amino acid concentration rather than that of sugar augmented the decrease of glycation of lens proteins.     

Utility of urine and blood cultures in pyelonephritis

OBJECTIVE: To determine how often the results of urine and blood cultures led to changes in antibiotic therapy for patients discharged from the hospital with the diagnosis of pyelonephritis. METHODS: A retrospective chart review was performed of consecutively admitted patients, 10-90 years old, with an ICD-9 discharge diagnosis of acute pyelonephritis. All patients were admitted to a university-based, tertiary care center and a large HMO medical center from 1993 to 1994. The association of urine and blood culture results with a change in antibiotic therapy was assessed. RESULTS: Of the 194 patients who met inclusion criteria, 189 (97%) had urine cultures obtained at the time of admission and 139 (71%) had blood cultures obtained. Ampicillin, gentamicin, or both were given as initial antibiotics 81% of the time, and isolated organisms from urine or blood were sensitive to the empiric antibiotics 95% of the time. Most (171/189; 90%) urine cultures were positive, but only 9 (5%) of these led to a change in antibiotic therapy. 80% of the urinary pathogens were Escherichia coli, 5% Enterococcus, 5% Proteus, and 4% Klebsiella. Only 40 (29%) of the 139 blood cultures were positive; none prompted a change in antibiotics. There were no cases in which blood and urine cultures grew different pathogens. CONCLUSIONS: Urine cultures are useful in directing antibiotic therapy in patients with the discharge diagnosis of acute pyelonephritis and support a change in therapy in 5% of cases. Among the patients in this study, blood cultures results did not lead to changes in antibiotic therapy. These findings warrant prospective, multicenter evaluation.     

The effects of acetyl-L-carnitine and sorbinil on peripheral nerve structure, chemistry, and function in experimental diabetes

Nerve conduction velocity (NCV) increased with age in nondiabetic male Wistar rats for the first 26 weeks of life. The NCV of animals made hyperglycemic at age 6 weeks by administration of streptozotocin (STZ) also increases, but at a slower rate. Animals with 4 weeks of hyperglycemia and reduced NCV treated with an aldose reductase inhibitor (sorbinil) or a short-chain acyl-carnitine (acetyl-L-carnitine [ALC]) daily for 16 weeks showed an improvement in NCV. Morphometric studies of tibial nerves collected from animals after 20 weeks of hyperglycemia (age 26 weeks) showed a consistent reduction in the width of the myelin sheath and little change in axon area. The number of large myelinated fibers (>6.5 microns) found in nerves collected from hyperglycemic animals was less than the number found in nondiabetic animals. Treatment of hyperglycemic rats with either sorbinil or ALC was associated with increased NCV, myelin width, and large myelinated fibers. The apparent metabolic effect of these agents was similar for fatty acid metabolism, but different for polyol pathway activity. We conclude that in animals hyperglycemic long enough to slow NCV, sorbinil and/or ALC treatment reduces the functional, structural, and biochemical changes associated with hyperglycemia that occur in the myelin sheath.     

Time-dependent, spontaneous release of white cell- and platelet-derived bioactive substances from stored human blood

BACKGROUND: The mechanisms of the detrimental effects of perioperative allogeneic blood transfusion are still unclear. Previous studies have suggested a higher incidence of adverse effects after the use of blood stored for prolonged time. Therefore, a possible time-dependent release of various white cell- and platelet-derived bioactive substances in stored human red cell suspensions was studied. STUDY DESIGN AND METHODS: Whole blood (6 units), plasma-reduced whole blood (6 units), and saline-adenine-glucose-mannitol blood (6 units) from 18 unpaid, normal blood donors were stored under standard blood bank conditions at 4 degrees C for 35 days. After refrigeration, samples were collected from all blood bags on Days 0, 2, 5, 9, 14, 21, 28, and 35 of storage. Extracellular concentrations of eosinophil cationic protein, eosinophil protein X, plasminogen activator inhibitor 1, myeloperoxidase, and interleukin 6 were analyzed by enzyme-linked immunosorbent assay and radioimmunoassay. The total intracellular and donor plasma levels of these substances also were analyzed at the time of blood donation. RESULTS: Eosinophil cationic protein, eosinophil protein X, and myeloperoxidase increased 10- to 25-fold (p < 0.05) in a time-dependent manner in whole blood, plasma-reduced whole blood, and saline-adenine-glucose-mannitol blood during storage for 35 days. Plasminogen activator inhibitor 1 increased threefold to sixfold (p < 0.05) in whole blood and plasma-reduced whole blood, but not in saline-adenine-glucose-mannitol blood. Interleukin 6 was not detected in either plasma or samples obtained from the blood bags. CONCLUSION: Stored whole blood, plasma-reduced whole blood, and saline-adenine-glucose-mannitol blood may release white cell- and platelet-derived bioactive substances in a time-dependent manner, which may be related to the detrimental effects of perioperative blood transfusions. Therefore, prestorage white cell reduction should be considered for further improvement of red cell suspensions.     

Time-dependent changes in the density and hemoglobin F content of biotin-labeled sickle cells

Sickle red blood cells (RBC) are subject to a number of important cellular changes and selection pressures. In this study, we validated a biotin RBC label by comparison to the standard 51Cr label, and used it to study changes that occur in sickle cells as they age. Sickle RBC had a much shorter lifespan than normal RBC, but the two labels gave equivalent results for each cell type. A variable number of sickle, but not normal, RBC disappeared from the circulation during the first few hours after reinfusion. The number of biotinylated sickle reticulocytes was decreased by 50% after 24 h and 75% after 48 h, with a gradual decrease in the amount of reticulum per cell. The labeled sickle cells exhibited major density increases during the first 4-6 d after reinfusion, with smaller changes thereafter. A small population of very light, labeled sickle RBC was essentially constant in number after the first few days. Fetal hemoglobin (HbF) content was determined in isolated biotinylated sickle RBC after reinfusion, allowing an estimate of lifespan for RBC containing HbF (F cells) and non-F cells. The lifespan of sickle biotinylated RBC lacking HbF was estimated to be approximately 2 wk, whereas F cells survived 6-8 wk.     

Poststatin, a novel inhibitor of bradykinin-degrading enzymes in rat urine

The association of baseline serum total cholesterol, systolic blood pressure, smoking and body mass index with coronary heart disease (CHD) mortality was analyzed among 1,619 men aged 40-59 at baseline. Analyses were made separately for the first, second and third decade of follow-up. Serum cholesterol and smoking more than 9 cigarettes daily were strong predictors of risk of CHD death (n = 450) occurring early and late during the 30-year follow-up. After 20 years of follow-up, systolic blood pressure was no longer associated with CHD risk. In contrast, highest tertile of body mass index (over 24.7 kg/m2) was only then associated with increased CHD risk. The correlations between the baseline and the 30-year risk factor values were 0.42 for serum cholesterol (n = 444), 0.28 for systolic blood pressure (n = 444) and 0.57 for body mass index (n = 429). Our results showed large differences in the long-term predictive power of the classical coronary risk factors. The reasons for these differences are discussed.     

Cortisol levels in blood and urine of trotting horses

Statistical analysis of normally occurring cortisol levels in serum and urine of horses served to recommend thresholds for this corticosteroid in these body fluids, as application of exogenous cortisol as well as ACTH may elevate the cortisol concentrations above the proposed threshold. The present study contributes to the general issue of how to establish thresholds for trotting horses upon sportive examination. 100 randomly selected post competition serum and urine samples, respectively, were submitted to cortisol analysis by means of HPLC. Concentrations of the endogenous corticosteroid in serum and urine followed a log-normal distribution with mean values of 61 and 49 ng/ml, respectively. The probability was 1: 100,000 to exceed concentration limits of 230 (serum) and 394 ng/ml (urine). Designation of thresholds for cortisol has proven problematic and is discussed here.     

Effect of galactose and sugar substitutes on blood insulin levels in normal and obese individuals

Eighteen male patients between the ages of 25 and 50 were given on a double blind randomized basis (A) 40 gms. galactose (B) 50 gms. arabinogalactan and 0.11 gm. sodium saccharin (C) 2 gm. methyl cellulose and 0.083 gm. sodium saccharin and (D) 4 gm. galactose, all in 200 ml water. Blood glucose, galactose and insulin levels were determined during a six hour period before and after ingestion. The three first mentioned solutions tasted equally sweet, the fourth was essentially tasteless. None of these feedings altered plasma insulin or glucose levels. It appears that in contrast to other conclusions reached by earlier investigators sweet taste is unable to induce insulin secretion through neurogenic pathways.