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PubMedDate not supplied

The safety of lymphatic mapping in pregnant breast cancer patients using Tc-99m sulfur colloid.

This investigation was undertaken to assess the risk to the embryo/fetus associated with sentinel lymph node biopsy and lymphoscintigraphy of the breast performed in pregnant patients. Approximately 92.5 MBq (2.5 mCi) of filtered Tc-99m sulfur colloid was injected peritumorally the day before surgery in two nonpregnant women with breast cancer. The whole-body distribution of the radiopharmaceutical was evaluated using a gamma camera 1 hour after injection. We then calculated the absorbed dose to the embryo/fetus for three theoretical extreme scenarios of biodistribution and pharmacokinetics: 1) all of the injected radiopharmaceutical remains in the breast and is eliminated only by physical decay; 2) all of the injected radiopharmaceutical is instantaneously transported to the urinary bladder, where it remains and is eliminated only by physical decay; and 3) the injected radiopharmaceutical behaves as though it were administered intravenously, that is, it has the biodistribution and pharmacokinetics of Tc-99m sulfur colloid injected for a liver/spleen or bone marrow scan. The fetal radiation absorbed dose was then estimated for two Tc-99m dosages: 18.5 MBq (0.5 mCi) and 92.5 MBq (2.5 mCi). The Medical Internal Radiation Dosimetry (MIRD) program was used to estimate the absorbed doses to the embryo/fetus for the first two scenarios. Published data were used to calculate the doses for the third scenario. A single breast is not among the source organs in the MIRD program, so the heart was used as a surrogate in the first scenario. In the two breast cancer patients, whole-body gamma-camera images obtained 1 hour after radiopharmaceutical injection revealed no radioactivity except in the vicinity of the injection site. In the theoretical scenarios, with 92.5 MBq, the highest absorbed doses to the embryo/fetus were as follows: scenario 1, 7.74 x 10(-2) mGy at 9 months of pregnancy; scenario 2, 4.26 mGy during early pregnancy; and scenario 3, 0.342 mGy at 9 months of pregnancy. The maximum absorbed dose to the fetus of 4.3 mGy calculated for the worst-case scenario is well below the 50 mGy that is believed to be the threshold absorbed dose for adverse effects. Thus breast lymphoscintigraphy during pregnancy appears to present a very low risk to the embryo/fetus.

Breast Neoplasms↗
PubMed1991

Studies on the relationship between serum colloidal reactions (ZTT and TTT) and IgG subclasses, especially IgG1 and IgG2.

The relationship between zinc sulfate turbidity test (ZTT and thymol turbidity test (TTT), and IgG subclasses, especially IgG1 and IgG2, was studied. Serum colloidal reactions of specimens from patients with IgG-myeloma usually show abnormally high values in ZTT and low values in TTT. But in some cases, values in ZTT and TTT are both low, and in a few cases both values are abnormally high. In order to see the reason why IgG-myelomas are classified into these three groups according to serum colloidal reactions. IgG subclasses of monoclonal proteins (MPs) isolated by zone electrophoresis were determined by immunodiffusion with anti IgG-subclasses. Results revealed that IgG1-myeloma showed high ZTT and low TTT and IgG2-myeloma showed low ZTT and TTT. Only two out of our 29 cases with IgG-myeloma showed high ZTT and TTT. MP from one of them belonged to IgG1-kappa and that from the other to IgG2-lambda. We checked the relationship between turbidity tests and electrophoretic mobility of MP and also that between these tests and L-chains' type of MP, but did not find any relationship between them. These findings suggest that IgG1 innately reacts with ZTT but not with TTT, while IgG2 does not react with any of these tests. MP from cases showing high values in both ZTT and TTT may have a special idiotype.

Antibodies, Monoclonal↗
PubMed1993

UV-induced colloid milium.

A 39-year-old woman is reported who developed numerous confluent yellowish semitranslucent papules of the face over 8 months. The patient habitually exposed herself to UVA-radiation twice a week for 7 years for aesthetic reasons. Histological, histochemical and immunohistochemical examinations were consistent with the diagnosis of adult colloid milium. A review of the literature is discussed. This case emphasizes the close relationship between long-term sun exposure, solar elastosis and adult colloid milium.

Adult↗
PubMed1993

Silver-enhanced colloidal-gold labelling of rabbit kidney collecting-duct cell surfaces imaged by scanning electron microscopy.

The luminal cell surfaces of rabbit kidney cortical collecting-duct cells were labelled with peanut lectin (PNA) and investigated by scanning electron microscopy. Labelling was performed either on 20-microns-thick cryostat sections from prefixed and cryoprotected rabbit kidney tissue or on cultured collecting-duct epithelium using biotinylated PNA and a 6-nm colloidal-gold-coupled antibody against biotin. Colloidal-gold labels were detected at low magnification (2000-4000x) using silver enhancement. Coating with chromium allowed simultaneous imaging of both cell-surface morphology and labelling topography in the backscattered electron imaging mode. Our results show that PNA binding is specific for a subtype of intercalated cells equipped with microvilli on the luminal surface. The presented method promises to be useful for the identification of specific cell types in heterogeneous tissues.

Aging↗
PubMed1981

Ultrastructural study of lichen planus: an evaluation of the colloid bodies.

Colloid bodies, which are eosinophilic, dyskeratotic, damaged epidermal cells that show signs of fibrinoid necrosis and premature keratinization, may play a role in the pathogenesis of lichen planus. An ultrastructural study of two patients with lichen planus focusing on the colloid bodies suggests the possibility of these bodies initiating the lichenoid dermal reaction.

Colloids↗
PubMed1985

Hemorrheological effects of colloidal plasma substitutes infusion. A comparative study.

Our objective was to investigate experimentally the easily overlooked effect of the clinical use of colloidal plasma substitutes on tissue perfusion. The experimental animals were dogs, and the study was carried out using several independent rheological experimental methods. The following are the principal findings: 1) Based on the observations made under a microscope, the stability of blood suspensions was best maintained by dextran-40 (Dex 40) and hydroxyethyl starch (HES0.55; Hespander), both of which cause little rouleaux formation by erythrocytes. In addition, the electronegativity of the erythrocyte membrane was simultaneously elevated. 2) The blood viscosity was greatly affected by the hematocrit and the serum protein concentration. 3) At a high shear rate, the blood viscosity among these colloidal plasma substitutes showed no great difference after infusion; in contrast, at a low shear rate, the blood viscosity after infusion of Dex 40 or HES0.55 was lower than after other substitutes. 4) The ratio of the viscosity at a low shear rate to the viscosity at a high shear rate is more significant and useful as a clinical indicator. On the basis of the preceding findings, Dex 40 and HES0.55 were generally superior to the other substitutes, especially HES0.55.

Blood Proteins↗
PubMed2005

Artificial colloids impair haemostasis. An in vitro study using thromboelastometry coagulation analysis.

BACKGROUND: Hydroxyethyl starch (HES) solutions impair haemostatic mechanisms. The impact of the degree of substitution (DS) of a HES solution on thromboelastometry tracings is unclear. Therefore we tested the hypothesis of whether the DS has an effect on the haemostatic defect caused by HES, and assessed whole blood coagulation by thromboelastometry coagulation analysis (ROTEM, Pentapharm Co., Munich, Germany) in serial in vitro haemodilutions of colloids. METHODS: Whole blood was withdrawn from 12 volunteers in a crossover study. Six per cent low-molecular weight HES with a high (HES MW 120 kDa/degree of substitution 0.7) and low (HES MW 130 kDa/0.4) degree of substitution, 4% succinylated gelatin (GEL) or 4% albumin (ALB) was added to citrated venous whole blood samples to make 20, 40, 60 vol.% end-concentrations of each of the solutions. Samples were analyzed by ROTEM. RESULTS: There was a comparable decrease in maximum clot firmness (MCF) and shear elastic modulus [G = 5000 x MCF/(100-MCF)] by HES 120/0.7 and HES 130/0.4 at 20 and 40 vol.% dilutions. At 60 vol.% dilution HES 120/0.7 decreased less alpha-angle and MCF than HES 130/0.4 (P < 0.05). With moderate dilutions all colloids shortened coagulation time (CT). At 20, 40 and 60 vol.% dilutions MCF and G were more decreased in both HES groups than in the ALB and GEL groups (P < 0.05). Furthermore, at 40 and 60 vol.% dilutions G deteriorated more in the GEL than in the ALB group (P < 0.05). CONCLUSION: In vitro the impact of the degree of substitution of HES solution on thromboelastometry coagulation analysis was modest. Haemodilution with gelatin and albumin induced fewer coagulation abnormalities than HES. In addition, the haemodilution with gelatin impaired coagulation more than albumin solution.

Adult↗
PubMed2005

Colloid vs. crystalloid preloading to prevent maternal hypotension during spinal anesthesia for elective cesarean section.

BACKGROUND: Hypotension associated with spinal anesthesia for cesarean section is still a clinical problem. Colloid solutions seem preferable to crystalloid solutions for preloading. In most studies the overall rate of hypotension is reported. Few studies have, however, investigated the maternal and neonatal consequences of different levels of maternal hypotension. METHODS: In this randomized, double-blinded study 110 patients presenting for elective cesarean section received either 1000 ml acetated Ringer's solution or 1000 ml 3% dextran 60 solution immediately before spinal anesthesia. The effect on overall hypotension, clinically significant hypotension (hypotension associated with maternal discomfort defined as nausea, retching/vomiting, dizziness or chest symptoms) and severe hypotension (systolic arterial pressure <80 mmHg) was studied. RESULTS: Dextran reduced the incidence of overall hypotension from 85 to 66% (P=0.03), reduced the incidence of clinically significant hypotension from 60 to 30% (P=0.002) and reduced the incidence of severe hypotension from 23 to 3.6% (P=0.004) compared to Ringer's solution. There were neither differences in neonatal outcome between treatment groups nor between neonates grouped after severity of maternal hypotension. CONCLUSION: Clinically significant hypotension seems to be a more suitable outcome variable than overall hypotension. The protective effect of the colloid solution increased with increased severity of hypotension.

Adult↗
PubMed1987

Low colloid osmotic pressure in very low birthweight infants receiving assisted ventilation.

Plasma colloid osmotic pressure (COP) was measured in three groups of very low birthweight infants. Babies in Group 1 (n = 8) were breathing spontaneously and had no respiratory disease. Those in Group 2 (n = 9) received assisted ventilation for hyaline membrane disease (HMD), and those in Group 3 (n = 7) received assisted ventilation for other reasons (five apnoea, two pneumonia). Both assisted ventilation groups had lower mean COP values than spontaneously breathing infants. Mean values (s.e.m.) for Groups 1, 2 and 3, respectively, were: 15.3 (0.6), 11.3 (0.4) and 11.9 mmHg (0.5) (P less than 0.001) on Day 1; and 15.2 (0.4), 12.9 (0.4) and 12.8 mmHg (0.3) (P less than 0.001) on Day 2. The increase from Day 1 to Day 2 was significant for those with HMD (P less than 0.05). Colloid osmotic pressure correlated with mean blood pressure (r = 0.51; P less than 0.001) but not with birthweight, gestation, crystalloid fluid intake or pH. The role of low COP in the pathogenesis of acute respiratory failure in infants with uncomplicated HMD is unclear, but such low COP may contribute to development of pulmonary oedema as a complication, particularly if the ductus arteriosus is still patent and the infants are given high volume intravenous fluids.

Blood Pressure↗
PubMed1978

Colloid osmotic pressure in surgical patients and its relationship to serum protein and albumin estimations.

A series of calculated colloid osmotic pressure (C.O.P.) results have been compared with concurrently performed total serum protein and serum albumin estimations. It is concluded that in most critically ill patients, serial estimations of total serum protein, which are very easy to perform using a hand refractometer or copper sulphate bottles, give a useful guide to the C.O.P. level. In a second series of patients, colloid osmotic pressure has been calculated before and after operation in a group of patients undergoing routine abdominal surgery, and significant falls in C.O.P. have been found to occur after operation. It is suggested that this may be a contributing factor in some of those patients who suffer postoperative respiratory complications.

Abdomen↗
PubMed2005

Juvenile colloid milium: a case report.

Juvenile colloid milium is extremely rare, has its onset before puberty, may be inherited, may be caused by ultraviolet light, and is thought to result from the degeneration of keratinocytes. We report a 7-year-old girl with juvenile colloid milium. To the best of our knowledge this is the first reported case in Turkey.

Child↗
PubMedDate not supplied

An argument for colloid resuscitation for shock.

A focused review of the physiologic mechanisms of colloid and crystalloid fluid resuscitations for acute critical illness is presented. This review suggests that postresuscitation plasma volume, cardiac output, left ventricular mechanical performance, and global and microcirculatory O2 supplies are more favorable with colloid therapy. Conversely, crystalloid may adversely affect microcirculatory blood flow and resultant O2 supply and use by ischemic tissues in shock. Poor relief of global and regional hypoxia may persist in critically ill patients after resuscitation with crystalloid.

Cardiac Output↗
PubMed2006

A case of argyria after colloidal silver ingestion.

BACKGROUND: Argyria is often considered an entity of the past, one which has largely disappeared with the cessation of silver usage in oral medications. However, with the practice of colloidal silver ingestion in current "alternative health" treatments, argyria should be considered in the differential diagnosis of blue-gray hyperpigmentation. METHODS: A single case report with clinicopathological correlation. RESULTS: Histological examination of skin biopsy specimen, which showed perieccrine brown-black granules, verified that colloidal silver rather than a prescribed medication was the source of the patient's dyspigmentation.

Administration, Oral↗
PubMed1989

Magnetic cell sorting using colloidal protein-magnetite.

Magnetic filtration of labelled cells as a way of separating leucocyte subpopulations was tested with a very simple and easy filtration device, using colloidal magnetite as the labelling reagent. In order to quantitate cell enrichment, a double label (both fluorescent and magnetic) was used, under conditions which labelled less than 10% of the cells in the initial sample. Up to 20 million cells were simply passed through a small magnetic filter with a hand-held syringe. Depletion of labelled cells in the suspension that passed through was threefold, and enrichment of labelled cells in the wash of the filter after its removal from the magnet was approximately fivefold. Factors which limited the quality of separation are discussed. Other, more preliminary, experiments found enrichments of 15- to 30-fold with the same colloidal magnetite and hand-held apparatus when the cell labelling system was more selective.

Animals↗
PubMed1988

Measurement of colloid osmotic pressure in submicrolitre samples.

A colloid osmometer for submicrolitre samples was constructed from solid polymethylmetacrylate and acrylnitrilmethylmetacrylate blocks, exposing a 0.85 mm diameter area of a Diaflo PM-30 ultrafiltration membrane. The unknown sample, contained in a 1-microliter glass micropipette, was applied to the membrane by suction, providing minimal exposure to air. The lower limit for successful application was 0.1-0.2 microliter. The accuracy of colloid osmotic pressure (COP) measurement depends strongly on the effective compliance of the pressure transducer. We tested three different systems: (i) A Hewlett-Packard 1280 'medical' transducer gave acceptable measurements on 1-microliter samples. In smaller samples (0.1-0.5 microliter) COP was underestimated, especially at COP greater than 10 mmHg. The equilibration time was 10-30 min. (ii) As (i), but with air pressure applied to the sample by a servoregulated pump, minimizing fluid transport through the membrane. Accurate measurements on 0.2-microliter samples were obtained in the course of 2-3 min, but the system required special instrumentation and some operating experience. (iii) An 'industrial' transducer, SensoNor AE-88o, with very low compliance, gave accurate measurements in the course of 1-3 min on samples as small as 0.1-0.2 microliter and COP up to 37 mmHg. We recommend system (iii) for samples smaller than 1 microliter.

Colloids↗
PubMed1988

Colloid osmotic pressure of interstitial fluid in rat subcutis and skeletal muscle: comparison of various wick sampling techniques.

Interstitial fluid for measurement of colloid osmotic pressure (COPi) was collected from rat subcutis and skeletal muscle with three wick methods; saline-soaked wicks implanted in vivo, titration with wicks preloaded with serial dilutions of rat plasma implanted postmortem (crossover method) and dry wicks implanted in vivo and post-mortem. When compared in 12 rats, the mean subcutaneous COPi of 14.2 and 13.3 mmHg as estimated with the crossover method and dry wick method, respectively, both exceeded the 10.7 mmHg obtained in saline-soaked wicks implanted for 60 min. Colloid osmotic pressure (COP) in fluid from dry wicks implanted subcutaneously was slightly lower than in plasma 5 min after implantation in vivo, then fell gradually, but remained stable the last 30 min of the 60 min in vivo implantation period and the first 30 min post-mortem, when again starting to rise. COP in fluid isolated from dry wicks implanted in muscle post-mortem approached or even exceeded that of plasma, suggesting leakage of intracellular proteins to wick fluid. Electrophoresis of dry wick fluid from subcutis showed a pattern similar to that of plasma, while protein fractions not present in plasma were observed in muscle wick fluid. For measurement of COPi we recommend the use of dry wicks implanted post mortem for subcutis and saline-soaked or dry wicks implanted in vivo for 90-120 min for skeletal muscle.

Animals↗
PubMed1986

Transport mechanisms of biological colloids.

An effort was made to distinguish among various mechanisms by which colloidal particles can be transported through liquid solutions. Figures 1-3 provide a visual (Figure: see text) summary of these differences. The various "phoretic" motions (electrophoresis, diffusiophoresis, osmophoresis) differ from sedimentation in that the driving forces operate within a thin interfacial layer at the surface of a particle rather than on the bulk of the article. Because of these surface forces, the velocity field of solvent dragged by a particle undergoing phoretic motion is much weaker (O(r-3)) than in the case of sedimentation (O(r-1)). As a consequence, particle-particle and particle-pore interactions are weak for the phoretic motions; Figures 4 and 5 demonstrate this point. It should be emphasized that the results presented in this paper are strictly valid only for very thin interfacial layers (kappa-1 much less than a, L and K much less than a). The Einstein relation (Eq. 1), which applies to sedimentation and diffusion with Equation 2 used for f, has been incorrect for the phoretic transport. As shown in Table 2, there is no unique value of f that fits all the phenomena, and in fact the magnitude of f for phoretic motion greatly exceeds the Stokes' law coefficient. Unfortunately, Equation 1 is well ingrained in the literature; one objective here was to bring its inadequacies to light. The phoretic transport processes offer important advantages in separations because of the selectivity that may be achieved through surface chemistry. For example, experiments are underway that demonstrate transport of particles across porous membranes by diffusiophoresis. It may prove economically attractive to develop both analytical and preparative separation methods that rely more on the surface properties of biological colloids rather than just their size.

Biological Transport↗
PubMed1986

Detection of mucus glycoconjugates in human conjunctiva by using the lectin colloidal gold technique in TEM. I. A quantitative study in normal subjects.

We applied a specific cytochemical reaction to characterize the glycoconjugates produced by goblet and non-goblet epithelial cells of normal human conjunctiva. For this purpose we utilized the lectins, proteins of vegetal origin, which are extremely sensitive in binding glycosidic residues. In particular, we used WGA, PNA, SBA and ConA conjugated with colloidal gold as ultrastructural marker for Transmission Electron Microscopy. This technique allowed us also to perform a quantitative analysis, by counting colloidal gold particles present on mucus granules. In this way we analyzed the content both of goblet and non-goblet epithelial cells. In the former, WGA, PNA, SBA and ConA receptors, here reported in decreasing density, were present. In the latter WGA was always positive, SBA and PNA sometimes were negative, ConA was always negative. We speculate the different contribution to mucus production by these two sources may be important in evaluating tear film stability alterations occurring in those diseases in which non-goblet epithelial cell vesicles increase.

Carbohydrate Metabolism↗