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PubMed1981

Staining of colloid bodies by keratin antisera in lichen planus.

Immune sera against total keratin, as well as three keratin polypeptide subunits, were raised in guinea pig with different bands of stratum corneum fibrous proteins derived from normal human epidermis and isolated by SDS polyacrylamide gel electrophoresis. The staining pattern of the different polypeptide antisera using the indirect immunofluorescence and immunoperoxidase methods in biopsy specimens of normal human epidermis confirmed recently published results. Biopsy specimens from 10 lesions of lichen planus were studied by indirect immunofluorescence and immunoperoxidase methods utilizing the same four different specific antikeratin immune sera. Most often the staining pattern with the different immune sera was similar to that seen in normal keratinized epidermis. In all specimens, intense staining of the colloid bodies was detected with the different immune sera. This finding favors the concept that colloid bodies originate from keratin filaments. Control staining with pre-immune serum was always negative. In one case of bullous lichen planus, colloid bodies were not labeled by 67 K and 62 K immune sera, but were intensely stained with 55 K and total keratin antisera. Moreover, with 55 K immune serum there was more intense staining of certain basal cells. The correlation between these findings and previously published studies by electron microscopy is discussed.

Animals↗
PubMed2002

The effect of the combined administration of colloids and lactated Ringer's solution on the coagulation system: an in vitro study using thrombelastograph coagulation analysis (ROTEG.

UNLABELLED: Gelatin solutions are often given in clinical practice once the maximal dose of a median-weight hydroxyethyl starch (HES) has been reached. Colloids are usually combined with lactated Ringer's solution (RL). Whether the combined administration of colloids and/or crystalloids affects blood coagulation is not known. We diluted blood by 20%, 40%, and 60% with RL, gelatin (Gelofusin), 6% HES 130/0.4 (Voluven), and 6% HES 200/0.5 (Iso-Hes), as well as with combinations of these solutions at a ratio of 1:1 (gelatin/RL, 6% HES 130/0.4:RL, 6% HES 200/0.5:RL, 6% HES 130/0.4:gelatin, 6% HES 200/0.5:gelatin). Thereafter, blood was analyzed by using modified thrombelastograph coagulation analysis (ROTEG) and clotting time, clot formation time, and maximal clot firmness were determined. RL had the least effect on hemostasis. Gelatin administered alone impaired the coagulation system significantly less than each median-weight HES administered alone. We conclude that gelatin combined with 6% HES 200/0.5 or 6% HES 130/0.4 decreases hemostasis <6% HES 200/0.5 or 6% HES 130/0.4 administered alone. IMPLICATIONS: The effect of the combined administration of different colloids and/or crystalloids on coagulation is not known. We show that hemostasis is less impaired using a combination of gelatin and median-weight starches than using median-weight starches alone. Furthermore, the combination of lactated Ringer's solution and gelatin decreases the coagulation system to the same extent as the combination of lactated Ringer's solution and 6% hydroxyethyl starch 130/0.4.

Adult↗
PubMed1988

Pulmonary effects of crystalloid and colloid resuscitation from hemorrhagic shock in the presence of oleic acid-induced pulmonary capillary injury in the dog.

The effects of resuscitation with crystalloid and colloid solutions in the presence of increased pulmonary capillary permeability were studied. Twenty-four hours after oleic acid administration, dogs were anesthetized and bled to produce hemorrhagic shock. One hour later, resuscitation was performed with saline, 5% albumin, or 6% hydroxyethyl starch solution to restore and then maintain cardiac output at pre-oleic acid values for 6 h. Dogs were recovered and, 24 h later, were reanesthetized for final measurements. Oleic acid administration resulted in increases in pulmonary artery pressure, pulmonary vascular resistance, and extravascular lung water (EVLW). Resuscitation from hemorrhagic shock restored pulmonary hemodynamics to pre-hemorrhage levels and did not affect EVLW, PaO2, shunt fraction, dead-space-to-tidal-volume ratio, or pulmonary compliance. There were no differences in these parameters related to the choice of resuscitation fluid. Saline resuscitation markedly reduced plasma oncotic pressure and the plasma oncotic-pulmonary artery occlusion pressure gradient. Values for these two variables were markedly lower with saline than with colloid resuscitation. The authors conclude that the pulmonary effects of crystalloid and colloid solutions are similar in the presence of moderate increases in pulmonary capillary permeability.

Animals↗
PubMed1985

Ventilation scanning with technetium labeled aerosols. DTPA or sulfur colloid?

We have compared the distribution in the lungs of submicronic aerosols of either Tc-99m sulfur colloid or Tc-99m DTPA immediately after inhalation with the distribution 20 minutes later in 83 patients. Thirty-two of the 83 patients were active smokers. Of the 28 smokers who received Tc-99m DTPA aerosol, the total lung count fell by a mean of 27 +/- 14% between the 0 and 20 minute image. Eleven of these patients also had a major change in distribution of isotope during this time. In the nonsmoking patients total lung counts from Tc-99m DTPA fell by only 16 +/- 8% and none had a major change in distribution pattern. None of the smoking or non-smoking patients who received Tc-99m sulfur colloid had a significant change in count rate or distribution pattern over 20 minutes. The effects on the ventilation images of these rapid changes in count rate and distribution pattern after Tc-99m DTPA aerosol can be minimized by completing the ventilation study as quickly as possible after inhaling Tc-99m DTPA or by using a nondiffusible agent such as Tc-99m sulfur colloid.

Aerosols↗
PubMed1986

Intrathoracic abnormalities demonstrated by technetium-99m sulfur colloid imaging.

Since the scintillation camera enables us to include lower thorax in the views obtained during Tc-99m colloid imaging of the liver and spleen, intrathoracic pathology may be identified as relatively cold or hot areas in the thoracic cavity. Eighteen patients who underwent Tc-99m sulfur colloid imaging during a one-year period were found to have intrathoracic pathology demonstrated either as photopenic areas or as areas of increased radioactivity. These patients' clinical data and the results of other diagnostic modalities, including autopsy, were correlated with the Tc-99m images. The intrathoracic disease processes recognized were bacteremia, two cases; pleural effusion, two cases; lung pathology, one case; and cardiomegaly, 13 cases. With the Exception of two patients with bacteremia who had substantial radiocolloid sequestration by the lung, all the other patients had hepatic dysfunction. The presence of compromised hepatic function allows the visualization of intrathoracic abnormalities: photopenia suggesting pleural fluid collection or an enlarged cardiac silhouette (either photopenia or increased radioactivity occupying a large space in the anterior view to yield cardiothoracic ratio of greater than 50%). Therefore, Tc-99m sulfur during colloid liver-spleen imaging, patients with hepatic dysfunction may incidentally demonstrate intrathoracic pathology, especially cardiomegaly.

Aged↗
PubMed1991

The role of Tc-99m IDA hepatobiliary and Tc-99m colloid hepatic imaging in primary biliary cirrhosis.

To assess the presence of primary biliary cirrhosis, 15 patients at various histopathologic stages were studied by Tc-99m IDA hepatobiliary and/or Tc-99m colloid hepatic imaging. In the earlier stages (I and II), seven of eight patients (88%) showed uniform hepatic retention of Tc-99m IDA. Of seven patients in the same stage, however, four (57%) showed no abnormality on Tc-99m colliod imaging. In three of these four negative patients (75%), uniform hepatic retention of Tc-99m IDA was noted. In the later stages (III and IV), all seven patients showed decreased clearance with or without delayed tracer appearance in the intestine and prominent hepatic retention on Tc-99m IDA imaging; with Tc-99m colloid imaging there was enlargement of the spleen and increased activity in the spleen and bone marrow. Thus, Tc-99m IDA imaging is considered to be more useful in revealing this functional disorder at the earlier stage of primary biliary cirrhosis and in evaluating progression from an earlier to a later stage of disease. Tc-99m colloid imaging also effectively evaluated progression.

Bone Marrow↗
PubMed1994

Discordant uptake of Tc-99m DTPA-galactosyl human serum albumin and Tc-99m Sn colloid in a patient with severe acute hepatitis.

A patient with recently diagnosed severe acute hepatitis underwent serial liver scintigraphy with Tc-99m Sn colloid and Tc-99m DTPA-galactosyl human serum albumin. In initial studies, radionuclide distribution on Tc-99m DTPA-galactosyl human serum albumin scintigraphy was completely discrepant to that on Tc-99m Sn colloid scintigraphy. In a follow-up study 1 month later, the distribution of both radionuclides in the liver appeared relatively homogeneous. The uptake of Tc-99m DTPA-galactosyl human serum albumin and Tc-99m Sn colloid reflects the function of hepatocytes and Kupffer cells, respectively. Both kinds of scintigraphic study may be helpful to assess histopathologic change of different hepatic tissue architectures.

Acute Disease↗
PubMed2005

Lymphatic drainage patterns on early versus delayed breast lymphoscintigraphy performed after injection of filtered Tc-99m sulfur colloid in breast cancer patients undergoing sentinel lymph node biopsy.

The axillary lymph node status is the most important predictor of prognosis and aids in breast cancer treatment planning. Patients with breast cancer now frequently undergo sentinel lymph node (SLN) biopsy rather than axillary lymph node dissection to determine the status of the regional lymph nodes. However, the optimal timing of radionuclide injection relative to the timing of SLN biopsy remains controversial. The objective of this study was to compare the lymphatic drainage patterns on lymphoscintigraphy performed at 15 minutes to 4 hours and at 18 to 24 hours after injection of filtered Tc-99m sulfur colloid, and to determine whether, over time, radiocolloid migrates to second-echelon nodes that are not the SLNs. Fifteen women with breast cancer (mean age, 55 years; range, 38-78 years) were scheduled to undergo SLN biopsy after each received an injection of 18.5 MBq (0.5 mCi) filtered Tc-99m sulfur colloid into the breast parenchyma surrounding the tumor or biopsy cavity. Both early (15 minutes to 4 hours after radionuclide injection) and delayed (18-24 hours after radionuclide injection) lymphoscintigraphy was performed in each patient. SLN biopsy was performed, followed by completion axillary lymph node dissection and planned breast surgery. In each patient the patterns of distribution of the radionuclide in the lymph nodes were the same on early and delayed lymphoscintigrams. These findings, that the distributions of radionuclide in lymph nodes are identical on early and delayed images obtained after injection of filtered Tc-99m sulfur colloid, suggest that performing SLN biopsy on the day after injection does not diminish the accuracy of the technique in predicting the potential site of metastasis in the regional lymph nodes in patients undergoing this procedure for breast cancer.

Adult↗
PubMed1983

The effects of resuscitation with hypertonic vs. hypotonic vs. colloid on wound and urine fluid and electrolyte losses in severely burned children.

Thirty-nine children with large burns were resuscitated with either a hypertonic (HLS) (17 patients), hypotonic (11 patients), or colloid (11 patients) fluid regimen. Burn dressings, bed linen, and urine were analyzed for electrolyte content. The group receiving HLS excreted the greatest percentage of the administered sodium load in the urine, significantly more than the other two groups; however, the combined wound and urinary sodium losses were significantly greater for the group receiving colloid. Sodium loss through the burn wound exceeded urinary loss fivefold in the colloid group. The volume of fluid lost across the burn wound was inversely related to the osmolality of the fluid used for resuscitation. Wound sodium loss was a function of both sodium and fluid load. The flux of fluid and electrolytes across the burn wound is a dynamic part of the resuscitation problem and is dramatically effected by the volume and concentration of fluid used.

Burns↗
PubMed1993

Differential clearance of colloid and crystalloid solutions from the lung.

The hypothesis that alveolar fluid clearance depends on factors other than the alveolar-capillary oncotic gradient was tested by comparing lung clearance rates of three different colloid solutions and isotonic saline. The solutions (4 mL/kg) were instilled into the lower lobes of New Zealand rabbits. Colloid solutions were diluted to produce a fixed gradient of 8 mm Hg for each experiment. Fluid clearance was calculated at 3 hours, using lung gravimetrics. Surface tension, as a measure of surfactant inhibition, was measured in separate experiments using bubble surfactometry. Airway inflammatory reaction was assessed by determining leukocyte counts in bronchoalveolar lavage (BAL). Data were analyzed using ANOVA with Tukey's test for multiple comparisons. Alveolar fluid clearance rates were significantly different (p < 0.01) between groups, and varied between 2.0 +/- 0.12 mL/kg (saline), and -0.04 +/- 1.7 (plasma). Clearance rates for saline and dextran 70 were similar despite an increased plasma-alveolar osmotic gradient. Surface tension, reflecting surfactant inhibition, was greater with the plasma (3.9 +/- 3.7 mN/m) compared with the other groups (range, 0.23-0.48 mN/m) (p < 0.01). Neutrophil migration was greater with the protein group, but there were no differences in total WBC counts between groups. These data suggest that fluid clearance from the airspaces is primarily dependent on factors other than simple colloid-capillary osmotic gradient. Alveolar PMN migration was not a major determinant of fluid clearance. The association between surfactant inhibition and decreased fluid clearance rate observed with homologous plasma suggests that protein interference with the surfactant monolayer may play a role in reducing alveolar fluid clearance.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Formation of labelled colloid in 99Tcm-DMSA due to the presence of bactericidal fluid.

The possibility that traces of bactericidal fluid in 99Tcm-DMSA could lead to the formation of labelled colloid, was explored. In vitro investigations were undertaken using ultracentrifugation techniques and photon correlation spectroscopy. The latter showed that both contaminated and uncontaminated DMSA contained colloidal (or particulate) material. However the presence of 10 microliters bactericidal fluid as contaminant was shown by ultracentrifugation to result in labelling of this colloidal material when 99Tcm was added to DMSA. Studies in a normal volunteer confirmed the results of the in vitro studies, in that significant liver and spleen uptake was observed after the administration of contaminated 99Tcm-DMSA.

Anti-Infective Agents, Local↗
PubMed1993

Distribution of 99Tcm-sulphur colloid during granulocyte colony-stimulating factor administration in autologous bone marrow transplantation.

The distribution of 99Tcm-sulphur colloid (99Tcm-SC) in 15 patients receiving human recombinant granulocyte colony-stimulating factor (G-CSF) following high-dose combination chemotherapy and autologous bone marrow transplantation (ABMT) for treatment of solid tumours was prospectively determined. 99Tcm-SC imaging was performed before treatment and at the time of leukocyte recovery during G-CSF administration. On the baseline 99Tcm-SC study, lung and bone marrow radiocolloid activity were not detected. The study performed during G-CSF infusion demonstrated lung colloid activity in 12 of 15 patients and bone marrow colloid activity in 11 of 15 patients. The average background corrected region of interest counts significantly increased for lung (P < 0.008), bone marrow (P < 0.0001) and cardiac blood pool (P < 0.05), and significantly decreased for liver (P < 0.0005) during G-CSF compared to the baseline study. No relationship between the distribution of 99Tcm-SC and response to therapy or patient outcome could be established. In conclusion, these data demonstrate a shift of 99Tcm-SC to lung, bone marrow and cardiac blood pool, and away from liver following high-dose combination chemotherapy and ABMT and during G-CSF administration in patients undergoing treatment for solid tumours.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Crystalloid and colloid resuscitation of uncontrolled hemorrhagic shock following massive splenic injury.

Using a standardized massive splenic injury (MSI) model of uncontrolled hemorrhagic shock we studied the effect of vigorous crystalloid or colloid fluid resuscitation on the hemodynamic response, and survival in rats. The value of massive fluid infusion in uncontrolled hemorrhagic shock following intra-abdominal solid organ injury is still controversial. The effect of crystalloid and colloid infusion was studied following massive splenic injury. The animals were randomized into six groups: group 1 (n = 8) sham-operated, group 2 (n = 12) MSI untreated, group 3 (n = 10) MSI treated with 41.5 mL/kg Ringer's lactate (large-volume Ringer's lactate, LVRL), group 4 (n = 14) MSI treated with 5 mL/kg 7.5% NaCl (hypertonic saline, HTS), group 5 (n = 10) MSI treated with 7.5 mL/kg hydroxyethyl starch (HES-7.5), and group 6 (n = 11) MSI treated with 15 mL/kg hydroxyethyl starch (HES-15). Following MSI mean arterial pressure (MAP) in untreated group 2 decreased from 109.1 +/- 4.5 to 49.8 +/- 9.6 mmHg (P < 0.001) in 60 min. Mean survival time was 132.1 +/- 18.7 min, and total blood loss was 30.2 +/- 4.1% of blood volume. LVRL infusion resulted in an early rise in MAP from 59.7 +/- 7.3 to 90.0 +/- 11.3 mmHg (P < 0.01), which then rapidly dropped to 11.7 +/- 4.5 mmHg (P < 0.001) after 60 min. The mean survival time was 82.5 +/- 18.2 min (P < 0.01), and total blood loss was 53.7 +/- 2.9% (P < 0.01). Total blood loss following HTS infusion was 32.2 +/- 4.0% and survival time was 127.9 +/- 19.7 min. HES-7.5 infusion only moderately increased bleeding to 44.2 +/- 3.9% (P < 0.05), but mortality remained unchanged. HES-15 infusion resulted in an increase in blood loss to 47.8 +/- 7.1% (0.01), survival time dropped to 100.7 +/- 12.3 min (P < 0.05). Vigorous large volume infusion of Ringer's lactate or HES following MSI resulted in a significant increase in intra-abdominal bleeding and shortened survival time compared to untreated, small volume HTS, or HES-7.5-treated animals. The hemodynamic response to crystalloid or colloid infusion in blunt abdominal trauma is primarily dependent on the severity of injury and the rate of fluid resuscitation.

Animals↗
PubMed2000

Crystalloids versus colloids for resuscitation in shock.

The optimal composition of fluid for volume resuscitation in critically ill patients has been the subject of controversy for decades. Clinicians are faced with several options, including crystalloid solutions of varying tonicity, several colloid preparations (albumin and others), and blood products. Some of these solutions may be differentially distributed between the intra- and extravascular, and intra- and extracellular compartments, accounting for a variety of physiological effects. Two recently published meta-analyses concluded that colloids afford no survival benefit in critically ill patients compared with crystalloids. Albumin infusion may be of more value in patients with cirrhosis, or in those at high risk of acute renal failure. Additional randomized trials will be needed to establish the optimal composition and volume of colloid or crystalloid solutions for resuscitation in shock.

Albumins↗
PubMed2005

Stability of radioactive colloids for radiation synovectomy: influence of X-ray contrast agents, anaesthetics and glucocorticoids in vitro.

AIM: This in-vitro study investigated the influence of the contrast agents iothalamate (Conray) and special preparations of iotrolan (Isovist) and iopromide (Ultravist) without ethylenediaminetetraacetic acid (EDTA), the anaesthetic Scandicain and the glucocorticoid triamcinolone on the stability of 90Y-, 169Er- and 186Re-radiocolloids used for radiation synovectomy. METHODS: Vials of 1 ml of synovial fluid and 0.02 ml of radiocolloid suspension (0.56-3.6 MBq) were mixed with 0.06, 0.6 and 1.0 ml of each contrast agent. In an additional series, 0.1 ml of Scandicain and 0.1 ml of triamcinolone were tested. Thin layer chromatography and ultrafiltration/centrifugation were performed between 1 h and 15 days after incubation with negative and positive controls. RESULTS: Within 24 h, 0.6 and 1.0 ml of Conray had mobilized 5-20% of the 90Y and 169Er out of the colloids. No interference between 186Re-colloids and Conray was visible before the ninth day after incubation. Iotrolan and iopromide without EDTA had no effect on the stability at shorter incubation periods of up to 6 days. The addition of Scandicain did not produce low-molecular 90Y or 169Er in the presence of synovial fluid. The fraction of low-molecular 186Re reached 4% after 24 h. Triamcinolone did not have any effect on stability in the presence of synovial fluid. CONCLUSION: The disintegration of the radioactive colloids can be attributed to either the formation of EDTA complexes or radiolytic effects. The volume of the injected contrast agent should be as small as possible to confirm correct intra-articular distribution.

Anesthetics↗
PubMed2003

Effects of crystalloid and colloid resuscitation on hemorrhage-induced vascular hyporesponsiveness to norepinephrine in the rat.

BACKGROUND: We have shown previously that hemorrhagic hypotension is associated with a progressive development of vascular hyporeactivity to norepinephrine (NE). The present study investigated whether select crystalloid or colloid resuscitation fluids would ameliorate this effect. METHOD: Anesthetized male rats were hemorrhaged to and maintained at a mean arterial pressure (MAP) of 50 mm Hg for 60 minutes. Rats (n = 7 per group) were then resuscitated with lactated Ringer's (LR), 7.5% hypertonic saline (HS) for 1 hour followed by LR (HS-LR), Hespan, or Hextend to restore and maintain MAP to 70 mm Hg over 4 hours. Additional hemorrhaged groups were resuscitated with LR to the baseline MAP (LR-BL) or received no resuscitation. A sham hemorrhage group served as controls. The responses of MAP and the blood flow of the superior mesenteric, celiac, left renal, and left femoral arteries to NE (3 microg/kg administered intravenously) were measured at BL (prehemorrhage); at the end of the hypotensive period; and at 1, 2, and 4 hours after resuscitation. RESULTS: Hemorrhagic hypotension significantly (p < 0.01) reduced the NE-induced pressor response in MAP and significantly reduced the contractile responses (reflected by the reduction of blood flow after NE administration) of the four arteries to NE. Hespan and Hextend infusion improved the NE response of MAP and the contractile responses of the observed arteries to NE significantly better than LR, HS-LR, or LR-BL. The colloids improved the vascular contractile responses to NE in the superior mesenteric and left femoral arteries and the pressor response of MAP to NE, to 80% to 90% of their basal response level compared with 40% to 60% with the crystalloid fluids (p < 0.05). LR-BL infusion resulted in hemodilution, with no added benefit to vascular responsiveness. CONCLUSION: These data suggest that hypotensive resuscitation to 70 mm Hg with colloids was better than crystalloids in improving vascular responsiveness to the pressor effects of NE and required smaller volumes. Normotensive resuscitation with LR was not better than hypotensive resuscitation. Not all vasculatures improved equally after fluid resuscitation.

Animals↗
PubMed2000

Colloidal aggregation with mobile impurities.

The structure and aggregation kinetics of diffusion-limited cluster-cluster three-dimensional monomeric aggregates and gels is investigated as a function of the molar fraction of two types of impurities. In one case the impurities are allowed to aggregate among themselves whereas in the other the impurities are mobile monomers that remain as such during the whole aggregation process. Computer simulations are performed on a simple cubic lattice for which the functionality of the aggregating particles is effectively 6. The first type of impurity shows a decrease in the fractal dimension when compared to that of a one component system at the same concentration. As a consequence of this decrease, the gelation concentration is lowered. At higher concentrations a gelling to nongelling transition was observed. In the nongelling regime the colloidal aggregates are kept apart by the impurity clusters, developing a local ordering. For the monomeric type of impurity, at large impurity molar fractions, a nonstructured nongelling phase appears at high enough concentration, in which the colloidal aggregates are kept apart by the sea of mobile impurities that inhibits the formation of a gel. Smaller molar fractions of mobile monomeric impurities strongly affect both the fractal dimension and the kinetics of the aggregating colloid.

Algorithms↗
PubMed2006

Ionic colloidal crystals: Ordered, multicomponent structures via controlled heterocoagulation.

We propose a new type of ordered colloid, the "ionic colloidal crystal" (ICC), which is stabilized by attractive electrostatic interactions analogous to those in atomic ionic materials. The rapid self-organization of colloids via this method should result in a diversity of orderings that are analogous to ionic compounds. Most of these complex structures would be difficult to produce by other methods. We use a Madelung summation approach to evaluate the conditions where ICC's are thermodynamically stable. Using this model, we compare the relative electrostatic energies of various structures showing that the regions of ICC stability are determined by two dimensionless parameters representing charge balance and the spatial extent of the electrostatic interactions. Parallels and distinctions between ICC's and classical ionic crystals are discussed. Monte Carlo simulations are utilized to examine the glass transition and melting temperatures, between which crystallization can occur, of a model system having the rocksalt structure. These tools allow us to make a first-order prediction of the experimentally accessible regions of surface charge, particle size, ionic strength, and temperature where ICC formation is probable.

Biophysics↗