Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Graded dextrans were used as tracers to study glomerular permeability in nephrotic rats. Two narrow range fractions were used, one which was approximately the same size as albumin (62,000 mol wt) and one which was considerably larger (125,000 mol wt). Nephrosis was induced with daily injections of an aminonucleoside of puromycin, and the animals examined after 7 days, when proteinuria is minimal, or after 10 days, when proteinuria has almost reached a maximum. At both stages and with both dextran fractions the following results were obtained: (a) dextran was retained for up to 3 h (the longest interval studied) in the plasma at high concentration; (b) there was a sharp drop in the concentration of tracer between the inner, looser portions of the basement membrane (lamina rara interna) and its outer denser portions (lamina densa), (c) accumulation of dextran was seen in the mesangial areas with time; and (d) no accumulation of dextran was seen in the slits at any time. These results are the same as those reported earlier in normal animals, and they demonstrate that in nephrotics the basement membrane still behaves as the main filtration barrier retaining most of the plasma proteins. Certain differences from the findings in normals were also noted in that increased amounts of the tracer were present on the epithelial side of the basement membrane: (a) in the urinary spaces; (b) in the subepithelial portions of the basement membrane; and (c) within lysosomes (protein absorption droplets) in the epithelial cytoplasm. In addition areas of thinning of the dense portions of the basement membrane (lamina densa) were seen which were accompanied by a corresponding widening of the less dense, subendothelial and subepithelial layers (lamina rara interna and externa, respectively). The presence of increased quantities of dextran on the epithelial side of the basement membrane indicates that the filter, i.e. the basement membrane, is leaky and allows increased passage of dextrans and therefore plasma proteins.
 ...
PMID:The permeability of glomerular capillaries of aminonuceoside nephrotic rats to graded dextrans. 115 Dec 87

The permeability of subepithelial capillaries in porcine endometrium was studied during midcycle and early pregnancy. Gilts were slaughtered on Day 13 or Day 15 of the oestrous cycle or pregnancy, 15 min after injection through the ear vein of 11.1 MBq of 125I-labelled human albumin in phosphate-buffered saline. The radioactivity of endometrial strips taken along the mesometrial and antimesometrial aspects of the uterine horn varied on average from 270 to 701 c.p.m./g and no difference (P greater than 0.05) was found between reproductive status, days of slaughter or sampling sites. The majority of the subepithelial capillaries showed ultrastructural evidence of increased vascular permeability, such as marked thinning of the capillary walls, especially on the side proximal to the epithelial basal lamina, multilayering and partial disparition of the endothelial basal lamina and abundant endothelial vesicles. Fenestrated pores were observed, but were rare. There was no obvious difference between reproductive status, days of sampling or sampling sites inside the uterus, suggesting that on Days 13-15 after oestrus the ultrastructural characteristics of porcine endometrial capillaries are little affected by the presence of attaching blastocysts and supporting the results obtained with radioactive albumin. Ferritin injected directly into a uterine artery of one gilt on Day 15 of pregnancy was carried through the capillary wall by endothelial vesicles, showing ultrastructural evidence of increased permeability.
 ...
PMID:Structural and functional aspects of porcine endometrial capillaries on days 13 and 15 after oestrus or mating. 155 88

The effects of variations in transmural pressure over a range of 0 to 200 mmHg on transendothelial transport of macromolecules were studied in the canine common carotid artery. The uptake of 125I-albumin per unit artery weight increased with rising pressure. There was no significant difference in albumin permeability per unit luminal surface area between 0 and 100 mmHg, but permeability nearly doubled when pressure was raised to 200 mmHg. The contribution of an increased rate of transendothelial vesicle diffusion, as evaluated from the experimental determination of the ratio of attached-to-free vesicles and theoretical modeling, was found to be negligible. The reduction in transendothelial vesicle diffusion distance due to pressure-induced thinning of the peripheral zone contributes to a 25% increase in permeability. With the use of colloidal Ag and Au of various sizes, vesicle loading of particles with diameters greater than or equal to 15 nm was found to be severely restricted at transmural pressure less than or equal to 100 mmHg, but it was significantly enhanced at 200 mmHg, when particles as large as 25 nm became detectable in endothelial vesicles and subendothelial space. This hypertension-induced increase in macromolecular transport across the endothelium may cause an overloading of the arterial wall with low-density lipoproteins and play a significant role in atherogenesis.
 ...
PMID:Effects of arterial pressure on endothelial transport of macromolecules. 648 72

Adjuvant polyarthritis (AP) in rats is known to result in extensive bone loss. This study investigates the mechanisms responsible for the early trabecular osteopenia evaluated at a single point in time--2 weeks after adjuvant injection--in the hindpaw of female Lewis rats using biochemical and histomorphometric methods. At this early point in time, the inflammation was generalized (inflammatory score, 20; albumin/globulin, -80% versus control). Histomorphometric analysis of the noninjected femur showed that the trabecular bone volume was significantly decreased (-28% versus control) in both proximal and distal parts, and the femur growth rate was unaffected. The trabecular osteopenia was associated with a 90% decrease in osteoid surface and a concomitant thinning (-19%) of the trabeculae. Both the double-fluorescence-labeled surface and the osteoblast surface were also markedly decreased (-75%). In addition, the mineral apposition rate was reduced (-50%) and the bone formation rate was decreased by as much as 90%. The trabecular bone volume was decreased in relation with the extent of double-fluorescence labeling (r = 0.38, p = 0.03) and bone formation rate (r = 0.42, p = 0.01), suggesting that the generalized osteopenia resulted from the reduced bone formation. This was associated with a 26% reduction in plasma osteocalcin. Neither the osteoclast surface nor the number of osteoclasts was consistently affected. However, urinary hydroxyproline was increased by 100-200%, which likely reflected the cartilage and bone destruction at the site of injection. The present data show that the early extensive osteopenia observed 2 weeks after AP induction in rats results from defective bone formation with unchanged bone resorption. The role of cytokines in such an inhibitory effect on bone formation remains to be determined.
 ...
PMID:Bone morphometric changes in adjuvant-induced polyarthritic osteopenia in rats: evidence for an early bone formation defect. 832 7

We evaluated the radiological, biochemical and growth hormone (GH)/insulin-like growth factor-I (IGF-I) changes in 10 children with severe protein-energy malnutrition (PEM) who had rachitic manifestations (group 1), 10 children with severe PEM without clinical signs of rickets (group 2), and 10 children with normal body weight-for-length and -age, suffering from vitamin-D-deficiency with signs of florid rickets (group 3) and 10 normal age-matched children (group 4). Serum calcium (Ca2+), phosphorus (PO4), and albumin concentrations were markedly decreased in the two groups with PEM. Malnourished children with rickets had significantly higher serum alkaline phosphatase (ALP) concentrations compared to the malnourished group without rachitic manifestations. Radiological evaluation of the two groups who had rachitic manifestations revealed demineralization of long bones, thinning of the bony cortex, increased formation of osteoid tissue, and metaphyseal changes including cupping, fraying, and flaring. The incidence of these radiological findings did not differ among the well-nourished and the malnourished groups with clinical signs of rickets. However, the incidence of fracture of the shaft was higher (40 per cent) in the malnourished group compared to the well-nourished group (10 per cent) with rickets. In the malnourished group without clinical evidence of rickets, demineralization and cortical thinning was detected in 40 per cent without significant metaphyseal changes. Basal concentrations of GH and peak GH response to clonidine were significantly elevated and IGF-I concentrations were significantly depressed in the malnourished groups v. the other two groups. There were no significant differences in the fasting and the clonidine provoked GH levels or IGF-I concentrations between the rachitic children (group 3) and the normal children. These data suggest that in rachitic children there is not a major role for circulating GH (and by implication IGF-I) on bone mineralization. However, during malnutrition decreased IGF-I production can slow or stop epiphyseal growth and might contribute to the demineralization of the cortex of long bones.
 ...
PMID:Radiological, biochemical, and hormonal changes in malnourished children with rachitic manifestations. 882 Jun 18

To investigate the possibility of hemodilution with oxygen carrying fluid, we measured the viscosity effects of LEH which was suspended in different weight percentage of plasma expanders for different shear rates. All of LEH/Plasma expander suspensions show shear thinning flow behavior, and the viscosity of those suspensions increase with increased the weight percentage of each expander in suspensions for a fixed shear rate. Compared the viscosity data to those of human blood at 40% of hematocrit, LEH/albumin suspensions contained with 4% to 8% of albumin are the most suitable, whereas LEH/dextran (Dex) suspensions contained with 6% Dex70c is the least favorable suspension media for LEH. In point of viscosity effects, hemodilution with LEH/albumin or LEH/0.9% oxypolygelatin (Gel) may be valuable for further testing their efficacy in animal model.
 ...
PMID:Viscosity measurements for LEH suspended in different plasma expanders. 924 34

The potential role of transient sarcolemmal membrane wounding as a signal transduction event for cardiomyocyte hypertrophy was evaluated in rats with short-term pressure overload caused by banding of the proximal aorta. This procedure resulted in significant increases in left ventricular systolic (1.5-fold) and end-diastolic (2.6-fold) pressures and wall stresses that were associated with significant wall thinning and cavitary enlargement. Quantitative image analysis of frozen sections of the stressed ventricles obtained 60 minutes after banding demonstrated a 6- to 10-fold increase in cytosolic staining with a horseradish peroxidase-labeled anti-albumin antibody compared with sham-operated controls, indicating that an increase in transient sarcolemmal membrane permeability (wounding) is an early response to an abrupt increase in hemodynamic load in vivo. We conclude that an intense hemodynamic stress in vivo can result in histologically detectable cardiomyocyte wounding.
 ...
PMID:Cardiac myocyte membrane wounding in the abruptly pressure-overloaded rat heart under high wall stress. 936 53

Glucose degradation products (GDP) are carbonyl compounds, that are formed by heat sterilization of conventional peritoneal dialysis (PD) fluids. Carbonyl compounds are known to be toxic in vitro and potentially toxic also in vivo. The aim of this study was to evaluate the effects of daily, short-term exposure of the peritoneum to very high concentrations of GDP in vivo on peritoneal transport parameters and on peritoneal morphology in a well-established rat model of PD. Rats were exposed to three daily intraperitoneal (IP) injections (10 ml) for 9 days of a largely neutral (pH 7.2) PD fluid containing 1.5% glucose and sterilized by filtration, with (n = 8) or without (n = 8) the presence of different carbonyl compounds in concentrations 100 times higher than those reported in commercial PD fluids. Seven rats, not subjected to any exposure, served as controls. After the exposure, the rats were subjected to acute PD in 4-hour dwells. Twenty milliliters of 4% glucose dialysis fluid were instilled into the rat peritoneal cavity. Blood and dialysate samples were taken during the dwell for measurements of dialysate sodium, and for assessments of the mass transfer area coefficient (PS) for glucose and 51Cr-EDTA and of transperitoneal clearance (Cl) or radiolabelled albumin (RISA). At the end of the dwell, parts of the liver, diaphragm and peritoneum were removed for measurements of tissue cell density and thickness of the submesothelial peritoneal tissue. The exposure of the peritoneum to very high doses of carbonyl compounds did not affect the peritoneal transport of fluid and small solutes significantly, but seemed to slightly reduce lymph flow and albumin clearance out of the peritoneal cavity. Assessed after a hypertonic dwell, and compared to the situation in nontreated rats after the same kind of dwell, there was a significant thinning of the submesothelial tissue, but no difference in tissue cell density. It is concluded that short-term exposure of the peritoneum in vivo to very high doses of GDP resulted in almost no signs of acute toxicity.
 ...
PMID:Very high daily intraperitoneal doses of carbonyl compounds affect the morphology, but not the exchange characteristics, of rat peritoneum. 1124 88

Using 24-h ambulatory blood pressure (BP) monitoring and digitized M-mode echocardiography, we evaluated whether microalbuminuria is related to preclinical left ventricular (LV) diastolic dysfunction in hypertensive patients. We selected 87 never-treated hypertensive patients (mean 24-h BP > 140 and/or > 90 mm Hg); albuminuria was evaluated as mean value of 24-h urinary albumin excretion (UAE) from two 24-h urine collections. Microalbuminuria was found in 28 patients, classified as MA+ (UAE 30 to 300 mg/24 h); 59 patients had normal UAE (< 30 mg/24 h) and were classified as MA-. The MA+ and MA- groups did not differ with regard to age, sex, body mass index, or 24-h heart rate, whereas 24-h, daytime, and nighttime systolic and diastolic BP were significantly higher in MA+ than in MA-. The LV mass index was greater in MA+, as was the prevalence of LV hypertrophy; peak shortening rate of LV diameter, index of systolic function, was normal in all, but was lower in MA+. Peak lengthening rate of LV diameter and peak thinning rate of posterior wall, indices of diastolic function, were lower in MA+ and the prevalence of diastolic dysfunction was higher in MA+. UAE was inversely correlated with both indices of LV diastolic function, also after correction for age, 24-h heart rate, 24-h BP, and LV mass. In conclusion, in never-treated hypertensive patients, microalbuminuria is not only associated with greater myocardial mass, but is also related with preclinical impairment of LV diastolic function. This relation, independent from increased BP or LV mass, strengthens the role of microalbuminuria as an early and reliable marker of preclinical cardiac involvement.
 ...
PMID:Microalbuminuria as a marker of preclinical diastolic dysfunction in never-treated essential hypertensives. 1146 48

The effect of gastrointestinal nematode infections on bone development was investigated in growing sheep on pasture. Forty-five weaned lambs from six groups in a two-factorial design incorporating stocking rate (SR; low, medium and high) and presence or absence of infection on pasture were sampled in the late grazing season. Worm counts were performed at slaughter, and the left metacarpal bones were excised for bone assessment. Faecal egg counts and worm burdens, primarily of Ostertagia circumcincta and Trichostrongylus vitrinus, were considerably higher in the high SR infected group ("I-High") than in comparable animals at low or medium SRs, whereas uninfected groups showed negligible egg excretion. Clinical biochemistry revealed significantly reduced serum concentrations of albumin, calcium and alkaline phosphatase in infected lambs. Nematode infections were associated with significant reductions in bone mineral density (30% at high SR), measured by dual energy X-ray absorptiometry, and in bone size (9%). Histomorphometry indicated thinning of the trabecular structure and reduced bone formation in the infected groups, particularly the I-High group. Bone mineral density, bone tissue volume and structural changes were strongly associated with log-transformed worm counts. The study showed that lambs suffering from moderate to heavy degrees of naturally acquired gastrointestinal nematode infection developed marked osteopenia after weaning, i.eduring the later part of the grazing season.
 ...
PMID:Osteopenia and reduced serum alkaline phosphatase activity in grazing lambs naturally infected with gastrointestinal nematodes. 1157 36


1 2 3 Next >>