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At least 19 recordsLinked to original sources
PubMed1986

Influence of crystalloid versus colloid infusion on peripartum colloid osmotic pressure changes.

Plasma colloid osmotic pressure acts to retain fluid in the intravascular space. Intravenous crystalloids have been identified as one of the major factors contributing to the consistent peripartum decline in colloid osmotic pressure. This study was undertaken to compare the effect of two crystalloid infusions (1000 and 2000 mL Plasma-Lyte A) and a colloid infusion (1000 mL 5% albumin) on the peripartum colloid osmotic pressure. Before elective cesarean section, 45 parturients received one of the three infusions. The lowest mean maternal colloid osmotic pressure (16.6 +/- 1.1 mmHg, P less than .05 compared with baseline) occurred in the 2000-mL crystalloid infusion group eight to 16 hours postpartum. Although the colloid osmotic pressure fell in all groups postpartum, this reduction was significantly (P less than .05) less during the first 24 hours in the colloid infusion group. Minimizing this disruption of the colloid osmotic pressure to pulmonary capillary wedge pressure gradient may be clinically important in selected patients.

Cesarean Section↗
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↗
PubMed1986

Comparison of three RE agents-99mTc-phytate, 99mTc-sulfur colloid and 99mTc-Sb2S3 colloid in the rodent species.

99mTc-phytate, 99mTc-sulfur colloid and 99mTc-antimony sulfide colloid are recognised as RE agents in clinical nuclear medicine. Since these three agents exist in vitro in different forms of particulate aggregation it was of interest to compare their properties and to evaluate the merits and limitations of each of these agents. A comparison was carried out in rats and rabbits as a prelude to a systematic study in human subjects. Quality tested radiopharmaceuticals were prepared and their pharmacokinetics studied in rats. The blood clearance, tissue distribution and scinti-imaging patterns of the RE system were also compared in rabbits. All the agents have excellent localizing properties in the liver but differ in varying extents in their disposition in other tissues. 99mTc-sulfur colloid has some predisposition for the lungs while 99mTc-phytate has a little propensity for the kidney and gut at late time periods. 99mTc-Sb2S3 colloid shows a more pronounced concentration in the bone-marrow, and displays intermediate properties between 99mTc-phytate and 99mTc-sulfur colloid, besides being the most stable (in vitro) radiopharmaceutical in this series of RE agents.

Animals↗
PubMed1987

Colloid shift in technetium-99m sulfur colloid liver-spleen scans of trauma patients.

To assess the radiosulfur colloid distribution in the liver-spleen scans of trauma patients, 73 trauma patients (age: 4-74 years, mean: 32 years) who had Tc-99m sulfur colloid liver-spleen scans for trauma workup were studied and compared with the liver-spleen scans of 87 control patients (age: 2-64 years, mean: 36 years). Radiocolloid distribution was visually assessed by two physicians independently, and the areas of the greatest density in the liver and spleen on the posterior view that included both organs were compared. The scans were grouped into three grades: Grade I, liver density greater than spleen density; Grade II, both organs showing equal density; and Grade III, splenic density greater than liver density (colloid shift). Forty-three of the trauma patients (59%) were in Grade III, 22 (30%) in Grade I, and 2 (11%) in Grade II. The control group had 12 (14%) patients in Grade III, 54 (62%) in Grade I, and 21 (24%) in Grade II. When the young adults and children of the trauma patients (age: 4-20 years, mean: 14 years) were looked at separately, 17 of 20 (85%) showed colloid shift (Grade III). It is concluded that there is a significantly higher incidence of colloid shift in trauma patients compared to control patients (P less than .01).

Adolescent↗
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↗
PubMed1989

In vitro colloid osmotic pressure of commonly used plasma expanders and substitutes: a study of the diffusibility of colloid molecules.

The rational choice of a plasma substitute for states of hypovolaemia depends partly on its colloid osmotic pressure (COP). We have measured the COP of 108 samples of plasma substitute across selectively permeable membranes which retain molecules greater than 10,000 dalton (COP10) and 50,000 dalton (COP50) the ratio COP50/COP10 providing a potential index of diffusibility of the smaller molecules across capillary membranes. 6% Hespan solution showed a particularly favourable COP50/COP10 ratio at 0.58 indicating a potential for good retention in the circulation whilst 3.5% Haemaccel showed a COP50/COP10 ratio of 0.18 indicating a potential for marked transcapillary diffusion, especially in states of capillary leak. In patients with normal capillary permeability both Gelofusine and Dextran 110 are likely to show adequate retention in the circulation with a COP50/COP10 ratio of 0.37 and 0.39 respectively. These are comparable to the retention of 4.5% human albumin (0.36) but all of the plasma substitutes tested, with the exception of Haemaccel, provided a higher COP across both membranes than 4.5% human albumin solution. An in vivo comparison of these plasma substitutes is required to confirm the advantages of macromolecular colloids in states of capillary leak.

Colloids↗
PubMed1987

Comparison of technetium-99m sulfur colloid and technetium-99m albumin colloid labeled solid meals for gastric emptying studies.

A Tc-99m albumin colloid (Tc-AC) kit has been introduced as an alternative to Tc-99m sulfur colloid (Tc-SC) for liver-spleen imaging. Since there is no need for boiling, the use of Tc-AC reduces preparation time and manipulation. Tc-SC is one of the most commonly used radiopharmaceuticals for the labeling of solid-phase markers in gastric emptying studies. In vitro studies were performed to evaluate the labeling efficiency and stability in hydrochloric acid and in human gastric juice of intracellularly labeled chicken liver and scrambled eggs labeled with Tc-SC and Tc-AC. Gastric emptying studies also were performed on 20 healthy volunteers with both Tc-SC and Tc-AC labeled scrambled egg sandwiches. There was no significant difference between Tc-SC and Tc-AC in the labeling efficiency of chicken liver (98% +/- 1% for Tc-SC, 96% +/- 2% for Tc-AC) and scrambled eggs (92% +/- 2% for Tc-SC, 91% +/- 3% for Tc-AC). However, both Tc-SC and Tc-AC labeled scrambled eggs showed a lower stability than chicken liver, particularly in human gastric juice. Gastric emptying curves from both meals in 20 normal subjects were also similar, with a mean half-emptying time of 85 +/- 13 minutes and 87 +/- 16 minutes for the meals containing Tc-SC and Tc-AC respectively. Tc-AC is a reliable alternative to Tc-SC as a radiotracer for solid-phase gastric emptying studies.

Adult↗
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↗
PubMed1987

The direct measurement of plasma colloid osmotic pressure is superior to colloid osmotic pressure derived from albumin or total protein.

Plasma colloid osmotic pressure (COP) has been calculated from both serum albumin concentration and plasma total protein concentration. These values have been compared to those measured directly using a membrane-transducer oncometer in a group of normal subjects, in a group of critically-ill patients with a variety of primary diagnoses and in a group of hypovolaemic patients before and after plasma volume replacement with 6% hydroxyethyl starch solution. In the normal samples, COP calculated from albumin (COPalb) underestimated the measured COP (COPm) by mean of 2.0 mmHg (p less than 0.002), with correlation coefficient r = 0.39(n/s). Similarly, the COPalb underestimated COPm by a mean of 5.7 mmHg (p less than 0.001) in the critically ill patient group; r = 0.38 (p less than 0.02). Furthermore, in the patients receiving plasma volume replacement serum albumin concentration fell by 13.1% (p less than 0.001) whilst COPm increased by 11.5% (p less than 0.002). In the normal subjects COP calculated from total protein concentration (COPtp) underestimated the COPm by 1.5 mmHg (p less than 0.02) with r = 0.65 (p less than 0.01). Conversely, in the patient samples, mean COPtp overestimated COPm by 3.5 mmHg (p less than 0.001) with r = 0.73 (p less than 0.002). We conclude that COPalb is an inadequate estimate of COPm particularly in patients where its use may have important clinical consequences. COPtp provides a reasonable estimate of COPm in normal subjects but in patients samples, where albumin: globulin ratio is low COPtp overestimates substantially in many cases. We advocate the direct measurement of COP in critically-ill patients.

Adult↗