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PubMed1986

[Hemodynamic change in the liver following hepatic resection in the dog. A comparative study by the 198Au colloid method, KICG and the H2 clearance method].

On the basis of our hypothesis that blood flow in the residual hepatic parenchyma is a determinant factor of posthepatectomy liver function, measurements were made of blood flow in the residual liver after 40% hepatic resection in dog. Adult mongrel dogs were divided into two groups, i.e., normal control and 40% hepatectomy, and evaluated for hepatic hemodynamics by 198Au colloid method, KICG and H2 clearance method. Blood biochemistry and, histology of the liver were also examined. The results are as follows: In the control group, hepatic blood flow by 198Au colloid method, KICG and H2 clearance method was found to correlate significantly with each other. In the 40% hepatectomy group, the hepatic blood flow index by both 198Au colloid method and KICG decreased in proportion to the amount of resected hepatic tissue initially and then increased as the liver regenerated. H2 clearance method showed that hepatic blood flow per unit weight of tissue decreased in the face of reduced hepatic volume in early stage of posthepatectomy period and returned to the preoperative level as the liver regenerated.

Alanine Transaminase↗

PubMed1988

An evaluation of technetium-99m tin colloid--its value in the diagnosis of renal transplant rejection.

The value of the Technetium-99m tin colloid (TTC) scan in the diagnosis of renal transplant rejection occurring more than 1 month following transplantation was assessed. To our knowledge, use of this agent has not previously been reported. Gamma camera imaging was performed on 15 occasions in 14 patients in whom plasma creatinine was rising and in three patients in whom renal function was stable. Both a qualitative and a quantitative assessment of images was made. The radioactivity recorded over the graft at 12-16 min post injection was expressed as a percentage of that recorded at 0-4 min. In the nine patients in whom graft perfusion was adequate to allow interpretation of the TTC scan and in whom rejection was diagnosed by biopsy (six cases) or on clinical grounds (three cases), the index ranged from 45 to 153%. In two patients the graft was poorly perfused and the accumulation of TTC was predictably low despite the presence of rejection. In the seven patients with either a stable creatinine or with rising creatinine not due to rejection, the index ranged from 5 to 43%. Previously reported studies have shown that sulphur colloids may be of value in diagnosing graft rejection. This study suggests that Tc99m tin colloid may be regarded as a suitable alternative scanning agent and that some simplification of data collection and analysis can be achieved.

Colloids↗

PubMed1988

Long-term observation following traumatic-hemorrhagic shock in the dog: a comparison of crystalloidal vs. colloidal fluids.

The effect of volume replacement with crystalloidal and colloidal solutions was analyzed in 40 anesthetized Foxhounds subjected to a standardized traumatic-hemorrhagic shock. Following trauma and hypotension (MAP 40 mmHg; 3.0 +/- 0.5 hr) the animals were randomized to treatment with autologous blood and hydroxyethyl starch 6% (HES 450/0.7), or human serum albumin 5% (ALB), dextran-60 6% (DX), Ringer's lactate (RL), and hyperosmolar saline 1.3% (HS), respectively. While analgesia and sedation were maintained, the hemodynamic measurements were continued for a 24-hr period. Crystalloids and colloids were found equally effective in maintaining the macrohemodynamics following resuscitation from traumatic-hemorrhagic shock. To keep central hemodynamics at pre-shock level required at least four times higher volumes of crystalloids than colloids. No specific advantage for one of the substitutes tested was found with regard to accumulation of water in the lung during the first 24 hr following shock in dogs. Extravascular lung water (thermo-dye) and organ water (gravimetry) were not different between the groups. However, fluid loss into the abdominal cavity as well as albumin extravasation into lung interstitium and abdominal cavity were more pronounced in the crystalloid-treated animals, whereas albumin redelivery by the lymph was decreased. The deterioration of tissue oxygen extractions as well as the changes in acid-base balance in both crystalloid-treated groups reflect the persistent microcirculatory inhomogeneity in spite of normal macrohemodynamics.

Acid-Base Equilibrium↗

PubMed1987

Pituitary intermediate lobe cysts: their formation and contribution to intraglandular (residual lumen) colloid.

3 types of bovine pituitary intermediate lobe cysts referred to in the present study as type 1, 2 and 3, normally occur in the deep zone of the intermediate lobe. The deep zone of the intermediate lobe, like the entire lobe, is composed entirely of basophilic cells which make contact and invade the posterior lobe. The deep zone abuts the marginal zone which faces the intraglandular lumen (residual lumen) between the anterior and intermediate lobe. The marginal zone is readily distinguished from the deep zone since cysts do not form there and the cells in the marginal zone continually break down into a colloid-like material that sloughs into the intraglandular lumen. The major characteristics of the type 1 cyst is the constant addition of intermediate lobe cells to its peripheral ring and the presence of an isolated clump of unknown material in the colloid. The type 2 cyst is characterized by the continual disintegration of its peripheral cells which are cast into the cavity forming its contents. The type 3 cyst is characterized by a peripheral ring made up of a single layer of basophilic intermediate lobe cells as well as a limiting membrane which surrounds the cavity of the cyst. Intermediate lobe cysts may be a reservoir of active intermediate lobe materials. It is widely accepted that intermediate lobe cells synthesize a family of peptide hormones and a recent study shows that intraglandular colloid housed in the intraglandular lumen (residual lumen) contains intermediate lobe peptide hormones ACTH, alpha MSH and beta LPH.

Animals↗

PubMed1984

Effect of atropine on oral clearance of a radiolabeled sulfur colloid.

Physical clearance is an important oral defense mechanism against gram-negative rods. We describe a simple technique that uses commercially available technetium-99m sulfur colloid to measure oral clearance. Technetium-99m sulfur colloid was sprayed into the mouth, and clearance was measured as the percent decrease in radiolabel counts over 2 hours using a radioisotope camera. Results using this technique compared favorably with clearance data using Tc-99m radiolabeled Escherichia coli. Atropine significantly decreased oral clearance rates of the colloid. Decreased clearance may be an important risk factor in the development of gram-negative rod colonization in hospitalized patients.

Atropine↗

PubMed1984

Effect of nonprotein colloid on postburn edema formation in soft tissues and lung.

We studied the effect of a nonprotein colloid solution--namely low molecular weight dextran (LMWD)--on edema formation in burned and nonburned soft tissue and lung. Adult sheep with lung and bilateral flank lymph fistulas were given a unilateral 25% to 30% full-thickness burn under ketamine anesthesia and followed for 72 hours. Resuscitation (24-hour period) was performed with lactated Ringer solution (LR) (n = 9) or 10% LMWD in saline (n = 8) to restore baseline vascular pressures and cardiac output. Interstitial edema and microvascular protein permeability were monitored by lymph flow (QL) and lymph to plasma protein ratio, respectively. With LR, QL values in nonburned skin and lung were increased twofold to threefold in the first 24 hours, while with LMWD, values remained at baseline. The nonburn edema with LR was due to the burn-induced hypoproteinemia state. The prevention of this process with LMWD was due to the generation of a twofold to threefold increase in the plasma to interstitial colloid osmotic pressure (COP) gradient. Burn QL was increased fivefold in both groups despite a higher COP gradient with LMWD. Net fluid requirements for the first 24 hours were 75 and 35 ml/kg for animals treated with LR and LMWD, respectively. After cessation of dextran administration in the second 24 hours, the COP gradients for the two groups were equal but QL in nonburned skin and net fluid requirements now increased significantly in the LMWD group. The development of nonburn edema was believed to be due to the persistent hypoproteinemic state. We conclude that edema formation in nonburned tissues, which is due to hypoproteinemia, accounts for a substantial amount of the net fluid requirements after thermal injury. This process can be prevented by infusion of a nonprotein colloid as long as the COP gradient is increased. Edema in burned tissue appears to be unaffected by changes in COP.

Animals↗

PubMed1978

Characterization of tin-technetium colloid in technetium-labeled albumin preparations.

The Tc-99m human serum albumin (HSA) system has been reinvestigated with gel filtration as the assay method. Other than Tc-99m HSA, two radioactive components have been isolated by this technique. Both components are tin-technetium colloids of differing particle sizes, and the relative quantity of each one is pH-dependent. The colloid has been further characterized by protein-induced x-ray emission analysis (PIXE) and by tissue distribution in rats. By this gel-filtration method, commercial Tc-99m HSA kits have been evaluated and have revealed varying amounts of colloids present.

Animals↗

PubMed1983

Colloid chemical aspects of pigment lithiasis in man: solubilization of calcium bilirubinate by bile salts (a preliminary report).

Calcium bilirubinate, an important constituent of pigment gallstones, can be solubilized in aqueous systems (including bile) to a considerable extent, depending on colloid mechanisms, strongly influenced by the actual ionic strength. Simple bile salt micelles protect colloid calcium bilirubinate against coagulation more effectively than do mixed bile salt-lecithin micelles, in particular when the latter are cholesterol saturated. The dissolved pigment does not enter the bile salt micelle. Pigment stone formation is believed to be due not merely to calcium bilirubinate overproduction, but also to pathological conditions leading to a coagulation of the colloid pigment in bile.

Bile Acids and Salts↗

PubMed1982

Relationship between colloid droplets of thyroid follicular cells and serum thyroglobulin concentration in neonatal rats after thyrotropin releasing hormone (TRH) injection.

Thyrotropin Releasing Hormone (TRH) shows the obvious and long-durated stimulation to the neonatal thyroid tissue through the pituitary. The sequential changes of serum thyroglobulin (Tg) levels and light and ultrastructural change in the cells of the thyroid gland were studied after TRH injection into neonatal rats. TRH injection induced a rapid increase of the colloid droplets in the thyroid follicular cells followed by a slow increase in serum Tg levels. Ultrastructurally, although marked surface activities consisting of formation of pseudopods and colloid droplets were observed after TRH injection, luminal colloid did not appear to go across the intercellular space between the thyroid follicular cells.

Animals↗

PubMed1980

A review of the colloidal gold marker system.

Colloidal gold can be used as a particulate marker for the detection and localization of target molecules by various modes of microscopy (light and fluorescent microscopy, scanning and transmission electron microscopy) using both direct and indirect labeling approaches. Several techniques are available for the preparation of gold markers in a size range of 5nm to 150nm, their mean size and shape characteristics and absorption spectra varying with particle size. Under appropriate conditions, colloidal gold will bind macromolecules by non-covalent electrostatic adsorption with little change in the specific activity of the bound macromolecule. This interaction is influenced by a number of factors including ionic concentration, pH conditions (in correlation with the protein pI values) and protein stabilizing levels. Presence of reactive protein on probes can be demonstrated and quantitated by direct and indirect radioactive binding assays and agglutination assays. These assays provide convenient procedures for characterizing stability, and behaviour in storage, of gold probes. Stability of gold probes under conditons where competing proteins are present, under freeze-thaw cycles and under SEM preparation conditions have been evaluated in this paper. Some of the basic procedures in the application of gold probes to cell labeling are briefly discussed together with certain limitations of the colloidal gold marker system. A bibliography of gold probe cell labeling studies is included.

Animals↗

PubMed1978

The determination of lymph shed by colloidal gold scanning in patients with malignant melanoma: a preliminary study.

Colloidal gold radionucleotide 198Au scanning can demonstrate the direction of regional lymphatic drainage in patients with primary malignant melanoma. Each of 32 patients with primary melanoma of the trunk received an intradermal injection of 0.1 mCi of 198Au colloid around the primary melanoma site. Imaging was accomplished with a tomographic scanner 24 hours following the injection. Twenty-seven of these patients underwent 36 regional lymph node dissections; nine had nodal metastases histologically demonstrated in the area (s) of nucleotide uptake. In clinical evaluation of up to 55 weeks, no patients demonstrated regional lymph node metastases in node groups which did not show preoperative gold uptake. Early evidence shows excellent correlation between the route of regional lymph node metastases and the direction of lymphatic flow to regional node groups, as demonstrated by gold colloid scanning. This procedure may be useful for evaluating patients with histologically defined high risk melanomas situated on the trunk in areas which drain to one or more lymph node regions.

Gold Colloid, Radioactive↗

PubMed1982

Detection of functional group on the liposome surface by colloid titration.

Suspensions of phospholipid liposomes (phosphatidylcholine, phosphatidylglycerol, phosphatidylethanoline and phosphatidylserine) were examined by colloid titration with polydiallyldimethylammonium chloride and potassium polyvinylsulfate as polycationic and polycationic and polyanionic titrants, respectively. In addition, the electrophoretic mobilities of the liposomes were measured with a cytopherometer. The following conclusions are drawn from the results of the titration: Phosphate and ammonium groups of phosphatidylcholine in liposomes form intramolecular or intermolecular salt linkages. Phosphate on the surface of phosphatidylglycerol liposomes shows a constant dissociation at above pH 3. Liposomes of phosphatidylethanolamine have no charge at low pH and a maximum negative charge above pH 10.5. On the surface of phosphatidylserine liposomes, the carboxyl group is completely dissociated at pH 6-7 and the phosphate group is released completely by the conversion of the ammonium ion to an amino group above pH 10.5. Stemming from these results, colloid titration can reveal the dissociation or the situation on the surface of liposomes more precisely than electrophoresis. Thus colloid titration is useful for determining the states of functional groups on the surface of phospholipid liposomes.

Colloids↗

PubMed1978

Colloid resorption in thyroid glands as revealed by scanning electron microscopy.

Colloid resorption from thyroid follicles in control and in calcitonin-treated rabbits was studied with the scanning electron microscope. Thus, an intense cell surface activity with several vesicles (exocytotic vesicles) and large pseudopods, sometimes cylindroids, is predominant on the thyroid follicular cells of calcitonin-treated rabbits. The pseudopods are irregular, mostly elongated, cup or dome-shaped and operate by phagocytosis or engulfment of colloid droplets (endocytosis). Only microvilli are visible on the cell surface of thyroid follicles in control rabbits. Comparative ultrastructural studies also revealed the occurrence of small exocytotic vesicles and large pseudopods in thyroid glands stimulated by calcitonin. The present findings demonstrate that the scanning electron microscopy better visualizes the colloid resorption and provides more details for the role of follicular cell surface in thyroid physiology.

Animals↗

PubMedDate not supplied

The use of colloids in clinical practice.

The use of colloid solutions for fluid resuscitation in hypovolaemic patients is widespread in clinical practice. This article describes the types of colloid agents which are currently available, their physicochemical properties, and adverse effects which may follow their administration. The relative merits of colloids compared with crystalloid solutions are discussed.

Colloids↗

PubMed1994

Thallium-201/technetium-99m-phytate (colloid) subtraction imaging of hepatocellular carcinoma.

UNLABELLED: This paper evaluates the clinical usefulness of 201Tl to image hepatocellular carcinoma (HCC), using 201Tl, 99mTc-phytate (colloid) and a three-headed SPECT camera. METHODS: The tumor-to-nontumor ratios (T/N) of 201Tl for different categories of HCC were generated. Tumors were emphasized by image subtraction (201Tl-99mTc-colloid). Thirty-three lesions in 16 patients (18 studies) with HCC were evaluated. There were 19 untreated nodular, five untreated diffuse, five local recurrent and four necrotic lesions after interventional therapy. RESULTS: The mean T/N were as follows: untreated nodular 1.54 +/- 0.31 (mean +/- s.d.), untreated diffuse 1.28 +/- 0.26, local recurrence 1.50 +/- 0.29 and necrosis 0.22 +/- 0.06. All the tumors (except necrotic areas) were enhanced by the image subtraction. CONCLUSION: Thallium-201 is useful for liver tumor imaging but 99mTc-phytate (colloid) is essential to discriminate 201Tl tumor uptake from normal liver accumulation. Image subtraction (201Tl/99mTc-colloid) is helpful in detecting HCC.

Aged↗

PubMedDate not supplied

[Characteristics of several indicators of colloid-osmotic homeostasis in middle-aged and aged persons].

Basic indexes of colloid-osmotic homeostasis have been studied in 50 patients. 25 elderly and old patients without surgical pathology have been examined, 25 young healthy persons were controls. It has been found that in elderly patients blood plasma COP tends to decrease, while blood plasma osmolality increases. The nature of changes gives evidence of lower reliability of colloid-osmotic homeostasis in geriatric patients. The results show that it is unjustified to use standard values of colloid-osmotic homeostasis characteristic of young and middle-aged patients during infusion therapy in geriatric patients.

Adolescent↗

PubMed1993

Formulation of technetium-99m-aerosol colloid with improved delivery efficiency for lung ventilation imaging.

Static imaging of lung ventilation in multiple views or with SPECT requires a 99mTc aerosol which does not wash out during imaging. Commercially available 99mTc colloids have suitable physical properties but are inefficiently delivered from jet nebulizers. An in vitro system was used to compare the delivery of various 99mTc radiopharmaceuticals from nebulizer solutions. Delivery of noncolloidal agents (pertechnetate, pentetate, imidodiphosphate, albumin) was much greater than that of colloids. However, addition of phosphate buffer to an in-house 99mTc-tin colloid produced an agent that was delivered as efficiently as the noncolloidal tracers and which shows promise for clinical use.

Aerosols↗

PubMed1996

[Detection of anti-Treponema pallidum antibodies with colloidal gold immunoprobes].

BACKGROUND: The aim of this study was to evaluate the usefulness of colloidal gold probes widely used in histochemistry and electronic microscopy for the serologic diagnosis of syphilis. METHODS: One hundred eighty-nine sera which had been submitted to the traditional fluorescent trigenemic absorption (FTA-ABS) test and had later been tested with the new colloidal gold probe method (IAT-ABS). RESULTS: Out of a total of 103 positive samples by FTA-ABS all were positive when tested by gold immunoprobes (sensitivity 100%). Eighty-six samples which were negative by immunofluorescence were all negative by IAT-ABS (specificity 100%). CONCLUSIONS: The new method of colloidal gold probes with the current microscopy is useful for confirming serologic diagnosis of syphilis.

Adolescent↗