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At least 19 recordsLinked to original sources
PubMed1975

Colloidal alpha-stannic acid and negative iron colloid as differential electron stains for surface proteins.

Colloidal alpha-stannic acid and a negative iron colloid obtained from ferric hydroxide and potassium ferrocyanide, both negative sols being stable within a wide pH range, were refined as surface protein electron markers. Because of the relatively small size of its particles, colloidal alpha-stannic acid was used for staining all surface proteins. According to the pH at which the negative iron colloid was applied, it revealed either all surface proteins, or because of its large colloidal particles, stained basic proteins. This differential staining capability of the iron colloidal has been demonstrated previously on various control preparations (Puvion E, Blanquet PR: J Microsc 12:171, 1971). Controls on the affinity of the two colloids to surface amino groups were carried out on rat liver, mouse fibroblasts, HeLa and KB cells, Ehrlich and Zajdela ascites cells subjected to prior enzymatic and chemical treatments (incubation with neuraminidase or phospholipase C, esterification, acetylation or lipid extraction). At any pH below 9, the two sols stained proteins in the outer hydrophilic leaflet of esterified cells with relative selectivity, but the alpha-stannic acid showed them more accurately. The iron sol did reveal at high pH protein components of high isoionic point on the surfaces of rat hepatocytes and ascites cells which had only been treated with neuraminidase.

Animals↗
PubMed1976

Distribution of yttrium 90 ferric hydroxide colloid and gold 198 colloid after injection into knee.

Thirteen knees were injected with yttrium 90(90Y) ferric hydroxide colloid, and 12 with gold 198(198Au) colloid for treatment of persistent synovitis. Retention in the knee and uptake in lymph nodes and liver were measured by a quantitative scanning technique. There was no significant difference in the retention in the knee of the two different colloids. A tendency towards higher lymph node uptake was observed with 198Au compared with 90y. The inflammatory activity of the knee at the time of treatment may have influenced the subsequent lymph node uptake of 198Au, but not that of the 90Y, nor the overall leakage of either from the knee. 90Yferric hydroxide colloid was retained in the treated knee at least as well as other colloids which have been used for this purpose.

Gold Colloid, Radioactive↗
PubMed1977

[Drainage of the radioactive lymphotropic tracers 198 Au-colloid and 99m Tc-sulfur-colloid from the orbit in rabbits (author's transl)].

In order to investigate lymph drainage from the retrobulbar space colloid solutions (198Au-colloid and 99mTc-sulfur-colloid) were injected into the right retrobulbar space of 31 rabbits. The distribution of radioactivity was measured in vitro after dissection with a sodium iodine crystal well counter and in some animals in vivo with the Gamma camera. More than 90% of the applied activity of either colloid solution was found in some animals up to the eighth day post injection in the retrobulbar space and in the liver. The remaining activity was recovered mainly from the regional lymph nodes, due to its smaller particle size higher values were registered in the experiments with 198Au than in those with 99mTc. The highest concentrations with up to 4,6% of the activity were observed in the deep cervical lymph nodes on both sides. Minor concentrations of activity were found ipsilateral in the superficial cervical and mandibular lymph nodes. Furthermore, small but significant activities were demonstrated in the optic nerves as well as in the contralateral retrobulbar space. The present data clearly substantiate the existence of lymph drainage, although a slow one, from the retrobulbar space. Moreover they indicate a reverse prelymphatic-lymphatic flow toward the optic nerves and the contralateral retrobulbar space. These results are of importance in the discussions of lymphostatic ophthalmopathy. The clinical application of this method is desirable; however, at present it is not yet practicable without further studies.

Animals↗
PubMed1977

Clinical comparison of 99mTc-labeled preformed phytate colloid and sulfur colloid: concise communication.

An in vitro preformed colloid preparation of 99mTc-Sn-phytate was compared both qualitatively and quantitatively with a commercial 99mTc-sulfur colloid kit in 30 patients. The degree of liver and spleen deposition of radiocolloid was, for practical purposes, the same. A slightly higher background was visually noted in 33% of the patients receiving preformed colloidal 99mTc-Sn-phytate, but it did not interfere with the diagnostic quality of the liver and spleen images. The only advantage of the phytate compound was a preparation time of less than 5 min.

Colloids↗
PubMed1975

Renal transplantation in the rat. III. The effect of colloidal and non-colloidal perfusates on the clearing of blood from the in vitro perfused rat kidney.

Rat kidneys were perfused in vitro with Perfadex (Gelin's solution) and a modified Collins' C3-solution with or without colloids. When the same flow rate was used the presence of 5% dextran 40, 5% albumin, or 10% albumin did not alter the clearing of 51Cr-tagged red blood cells. The main difference between the experimental groups was a significant increase in perfusion pressure when colloids were excluded from the perfusate. Results concerning the regional distribution of 51Cr-activity within the kidney are discussed.

Albumins↗
PubMed1975

Electron microscopical and biochemical analysis of colloid milium.

Two new cases of colloid millium were studied by several methods to examine if collagen is the source of colloid. Wound-healing experiments in the lesion revealed that colloid is reproduced de novo with possible interaction with epidermal cells. Unfixed, native colloid did not contain collagen and salt extraction did not alter the ultrastructure of colloid. Tissue culture of colloid fibroblasts produced colloid-like substance. These results suggest that colloid is not a degeneration product of collagen. Disc electrophoresis of extracted colloid produced a distinct band, which is absent in the normal skin control. Amino acid analysis of colloid suggests that colloid may contain the recently described class of glycoprotein, called "structural glycoprotein" that is not related to collagen because it does not contain hydroxyproline and hydroxylysine and contains only a small amount of glucose. These biochemical data support the conclusion reached in electron microscopical studies.

Amino Acids↗
PubMed1992

Distribution of intraperitoneally injected microspheres labeled with the alpha-emitter astatine (211At) compared with phosphorus (32P) and yttrium (90Y) colloids in mice.

The alpha-emitter 211At was bound to polymer microspheres with a diameter of 1.8 microns. The distributions in mice of intraperitoneally injected 211At microspheres, 90Y silicate colloid, and 32P chromic phosphate colloid were compared. The microspheres with 211At spread rapidly in the peritoneal cavity and remained mainly on the intraperitoneal surfaces. Intraperitoneal injection of 90Y colloid resulted in high levels in intraperitoneal fat and the diaphragm, but 1 day after injection 8.5% of the injected dose per gram was found in blood and after 6 days 2.5% was observed in bone. The highest accumulation of 32P was found in liver and spleen. The injection of additional nonradioactive chromic phosphate colloid resulted in an even higher accumulation of 32P in spleen and liver. The same phenomenon was not observed with 211At microspheres. It is suggested that it is not only the particle size which is important in the distribution of intraperitoneally injected colloid, but the amount of colloid, the type of colloid, the addition or presence of other substances such as ascites, and the animal species might also influence the distribution. In conclusion, the intraperitoneal distribution of 211At-labeled microspheres in mice was favorable compared with 90Y and 32P colloid. These data must be viewed cautiously since the distribution might be different in other animal species or humans.

Animals↗
PubMed1992

Effect of Helicobacter pylori infection on colloidal bismuth subcitrate concentration in gastric mucus.

Necropsy gastric mucus infected with Helicobacter pylori has a reduced capacity to concentrate colloidal bismuth subcitrate when compared with non-infected mucus. Mucus mounted in a modified in vitro diffusion chamber was bathed with colloidal bismuth subcitrate solutions at different concentrations and pH levels. Bismuth was measured by atomic absorption spectrophotometry to assess intramucus colloidal bismuth subcitrate concentrations. Bismuth concentrations in non-infected mucus were higher than in Helicobacter pylori infected mucus at all experimental colloidal bismuth subcitrate concentrations and pH levels. Regardless of the infection status, the intramucus concentration of colloidal bismuth subcitrate was dependent upon the concentration of the bathing solution and independent of the pH and the mucus thickness. Colloidal bismuth subcitrate solubility in saline solution varied with pH, and was least soluble in the pH range 1.1 to 3.25 and more soluble above and below this pH range. This study suggests that Helicobacter pylori infection is associated with physicochemical changes in the gastric mucus with a reduction in its capacity to concentrate colloidal bismuth subcitrate. Such a reduction may compromise the attainment of optimum colloidal bismuth subcitrate concentrations necessary for its bactericidal activity.

Adolescent↗
PubMed1975

Pulmonary edema related to changes in colloid osmotic and pulmonary artery wedge pressure in patients after acute myocardial infarction.

Pulmonary artery wedge and plasma colloid osmotic pressures and their relationship to pulmonary edema were investigated in 26 patients with acute myocardial infarction of whom 14 developed pulmonary edema. In the absence of pulmonary edema, both the pulmonary artery wedge pressure and plasma colloid osmotic pressure were in normal range; after onset pulmonary edema, a moderate increase in pulmonary wedge pressure and reduction in plasma colloid osmotic pressure were observed. When the gradient between the plasma colloid osmotic pressure and the pulmonary artery wedge pressure was calculated, highly significant differences were demonstrated (P less than 0.002). In the absence of pulmonary edema, this gradient averaged 9.7 (plus or minus 1.7 SEM) torr; following appearance of pulmonary edema, it was reduced to 1.2 (plus or minus 1.3) torr. During therapy with digoxin and furosemide, reversal of pulmonary edema was closely related to a concomitant change in the colloid osmotic-hydrostatic pressure gradient. These observations indicate that both increases in pulmonary capillary pressure and decreases in colloid osmotic pressure may follow the onset of pulmonary edema. Such decline in colloid osmotic pressure and especially the reduction in colloid osmotic-hydrostatic capillary pressure gradient may favor transudation of fluid into the lungs.

Adult↗
PubMed1976

Radioactive colloidal solutions and suspensions for medical use.

Radioactive colloidal solutions and suspensions are being widely used in the diagnosis and treatment of various diseases. The author considers the behaviour or radioactive disperse preparations in the body and devotes particular attention to the reasons for isotope transition from the colloidal to the ionic state. Questions concerned with producing and investigating radioactive colloidal solutions are discussed. In the light of the physical and chemical properties of the radioisotopes and of the disperse systems themselves, the author considers methods of producing the more important radioactive disperse preparations: colloidal solutions of noble metals; colloidal solutions containing phosphorus-32, yttrium-90 and isotopes of the rare-earth elements; colloidal solutions with with indium-113m, gallium-68, technetium-99m and rhenium-186; suspensions (macroaggregates and microspheres) for the diagnosis of lung diseases; and radioactive colloidal solutions based on quaternary ammonium base compounds.

Colloids↗
PubMed1975

The hydraulic conductivity of the rat proximal tubular wall determined with colloidal solutions.

The hydraulic conductivity of the rat proximal tubular wall was determined using colloidal solutions perfused in short (50--200 mum) (SMP) or long (90--200 mum) (LMP) proximal tubular segments. In SMP human serum albumin (HSA) or polyvinylpyrrolidone (PVP) was added to raffinose solutions. A Lp of 0.019 nl-min-1-mm-1-mm Hg-1 was found when high colloid concentrations were used while values of 0.055--0.092 were found when low colloid concentrations were used. In other experiments, the Lp was determined by perfusing short tubular segments with pure raffinose solutions. A value of 0.015 nl-min-1-mm-1-mm Hg-1 was found. This is twice the value found when raffinose solutions were perfused through long tubular segments and it is concluded that the short microperfusion technique overestimates Lp with a factor of two. When microperfusions of long tubular segments were conducted, PVP was added to an equilibrium solution consisting of NaCl (110 mM) and raffinose (80 mM). Lp was found to be 0.018--0.021 when high colloid concentrations were used, while a value of 0.029 was found when a low colloid concentration was used. As found in both SMP and LMP a decrease in Lp's with increasing colloid concentrations indicates that a significant influence of radial concentration differences is highly probable. It is therefore suggested that the highest Lp derived when using the lowest colloid concentrations represents the best estimate. With this Lp value (0.03--0.05 nl-min-1-mm-1-mm Hg-1) and the existing transtubular hydrostatic and oncotic pressure difference it can be calculated that these passive forces might constitute the driving force for 1/3 of the fluid reabsorbed in the proximal tubule.

Animals↗
PubMed1979

[Distribution, absorption and excretion of 198Au-colloid and Na251CrO4 in the chicken (author's transl)].

In order to clarify the suitability of 198Au-colloid and Na251CrO4 as a marker of transit of the gastrointestinal content of the chicken, the distribution, absorption and excretion of 198Au-colloid and Na251CrO4 in the chicken were examined. Orally administered 198Au-colloid was not absorbed by the gastrointestinal tract and excreted into feces. Intravenously injected 198Au-colloid was not excreted into the gastrointestinal tract through the gastrointestinal wall. On the other hand, orally administered Na251CrO4 was relatively well absorbed by the gastrointestinal tract and distributed over a whole body. Intravenously injected Na251CrO4 was excreted into the gastrointestinal tract through the gastrointestinal wall and bile ducts. It seemed that 198Au-colloid was not adhered to the gastrointestinal mucosa and consequently, the transport of 198Au-colloid in the gastrointestinal tract was not delayed. It is concluded that 198Au-colloid is highly suitable as a marker of gastrointestinal transit of the chicken but Na251CrO4 is unsuitable.

Administration, Oral↗