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PubMed2004

C-cells in colloid goiter.

PURPOSE: The aim of this investigation was to quantitatively evaluate C-cells in colloid goiters, analyzing 36 thyroids that were obtained through thyroidectomy from 24 patients with goiter and 12 normal glands from adult patients without thyroid disease, which were used as the control group. MATERIAL AND METHODS: On average, 6 different thyroid areas were sampled and labeled by immunohistochemistry with a monoclonal anticalcitonin antibody, utilizing the avidin-biotin-peroxidase complex. C-cells were counted in fields measuring 1 square centimeter, and the mean number of cells per field was then calculated. Data were statistically analyzed using the Mann-Whitney test. RESULTS: In the colloid goiter group, the number of C-cells ranged from 0 to 23 per field, while in normal controls they ranged from 20 to 148 per field. CONCLUSIONS: These results demonstrate a significant decrease of C-cell number in the colloid goiter group compared with control group, indicating that the hyperplastic process is restricted to follicular cells, to the detriment of C-cells, which probably cease to receive trophic stimuli.

Colloids↗
PubMed1999

Lipid peroxidation, antioxidant enzymes and glutathione levels in human erythrocytes exposed to colloidal iron hydroxide in vitro.

The free form of the iron ion is one of the strongest oxidizing agents in the cellular environment. The effect of iron at different concentrations (0, 1, 5, 10, 50, and 100 microM Fe3+) on the normal human red blood cell (RBC) antioxidant system was evaluated in vitro by measuring total (GSH) and oxidized (GSSG) glutathione levels, and superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px) and reductase (GSH-Rd) activities. Membrane lipid peroxidation was assessed by measuring thiobarbituric acid reactive substance (TBARS). The RBC were incubated with colloidal iron hydroxide and phosphate-buffered saline, pH 7.45, at 37 degrees C, for 60 min. For each assay, the results for the control group were: a) GSH = 3.52 +/- 0.27 microM/g Hb; b) GSSG = 0.17 +/- 0.03 microM/g Hb; c) GSH-Px = 19.60 +/- 1.96 IU/g Hb; d) GSH-Rd = 3.13 +/- 0.17 IU/g Hb; e) catalase = 394.9 +/- 22.8 IU/g Hb; f) SOD = 5981 +/- 375 IU/g Hb. The addition of 1 to 100 microM Fe3+ had no effect on the parameters analyzed. No change in TBARS levels was detected at any of the iron concentrations studied. Oxidative stress, measured by GSH kinetics over time, occurs when the RBC are incubated with colloidal iron hydroxide at concentrations higher than 10 microM of Fe3+. Overall, these results show that the intact human RBC is prone to oxidative stress when exposed to Fe3+ and that the RBC has a potent antioxidant system that can minimize the potential damage caused by acute exposure to a colloidal iron hydroxide in vitro.

Adult↗
PubMed1986

Fine anionic iron colloid and its use in light and electron microscopic detection of cationic sites in the rat kidney.

Ferric chloride, when boiled with ammonium thiocyanate, ammonia and cacodylic acid, is converted into a fine anionic iron colloid which consists of 1-1.5 nm electron dense granules and gives a distinct Prussian blue reaction. This colloid allows light and electron microscopic detection of ionized cationic sites in tissues at a pH range of 4.0-9.0. Light and electron micrographs of the rat kidney stained with this colloid are demonstrated. These micrographs indicate that the foot processes of glomerular podocytes and the brush border of the proximal convoluted tubule contain positively-charged groups in their intracellular matrices, and that the foot process plasma membrane fronting the Bowman's capsular space has positively-charged groups. The latter finding, together with our previous study (Murakami et al., 1986), suggests the co-existence of cationic and anionic sites on this foot process surface.

Animals↗
PubMed2000

The spatial relationship between the perineuronal proteoglycan network and the synaptic boutons as visualized by double staining with cationic colloidal iron method and anti-calbindin-D-28K immunohistochemistry in rat cerebellar nuclei.

The present study demonstrated the precise spatial relationship between meshes in the perineuronal proteoglycan network and the terminal boutons of synaptically associated axons. Sections from the rat cerebellum were stained with cationic colloidal iron (pH 1.0-1.5), and successively immunostained with anti-calbindin-D-28K monoclonal antibody. Cationic iron stained sulfated proteoglycans around the nerve cell of the medial cerebellar nucleus, whereas the anti-calbindin antibody labeled the Purkinje cells including their axons terminating on large neurons in the cerebellar nucleus. It was found that each synaptic bouton fits into a mesh of the perineuronal network. The individual meshes appeared to be divided by partitions faintly stained with the colloidal iron. Electron microscopy of cationic colloidal iron-stained ultrathin sections revealed that the synaptic boutons were separated from each other by the proteoglycan matrix and that each of them was further divided into two or more contact areas of presynaptic membrane by the same matrix. This suggests that individual synapses are protected against the effects of adjacent synaptic transmission, and that each of them may be subdivided by this manner of partitioning, like pads of a cat's paw.

Animals↗
PubMed2003

Comparison of colloid, thyroid follicular epithelium, and thyroid hormone concentrations in healthy and severely sick dogs.

OBJECTIVES: To compare serum concentrations of total thyroxine (TT4), free thyroxine (fT4), and thyroid-stimulating hormone (TSH), as well as measures of thyroid follicular colloid and epithelium, between groups of healthy dogs and severely sick dogs. DESIGN: Cross-sectional study. ANIMALS: 61 healthy dogs and 66 severely sick dogs. PROCEDURE: Serum samples were obtained before euthanasia, and both thyroid lobes were removed immediately after euthanasia. Morphometric analyses were performed on each lobe, and serum TT4, fT4, and TSH concentrations were measured. RESULTS: In the sick group, serum TT4 and fT4 concentrations were less than reference range values in 39 (59%) and 21 (32%) dogs, respectively; only 5 (8%) dogs had high TSH concentrations. Mean serum TT4 and fT4 concentrations were significantly lower in the sick group, compared with the healthy group. In the healthy group, a significant negative correlation was found between volume percentage of colloid and TT4 or fT4 concentrations, and a significant positive correlation was found between volume percentage of follicular epithelium and TT4 or fT4 concentrations. A significant negative correlation was observed between volume percentages of colloid and follicular epithelium in both groups. CONCLUSIONS AND CLINICAL RELEVANCE: TT4 and fT4 concentrations are frequently less than reference range values in severely sick dogs. Therefore, thyroid status should not be evaluated during severe illness. The absence of any significant differences in mean volume percentages of follicular epithelium between healthy and severely sick dogs suggests that these 2 groups had similar potential for synthesizing and secreting thyroid hormones.

Animals↗
PubMed1985

Interstitial fluid volume, plasma volume and transcapillary colloid osmotic gradient in patients with hepatic cirrhosis and fluid retention.

Colloid osmotic pressure in plasma (IIp) and in subcutaneous interstitial fluid (IIi) (wick technique), plasma volume (PV) and interstitial fluid volume (IFV) were measured in 12 patients with hepatic cirrhosis and fluid retention. The value of IIp (mean +/- SD) was 21.4 +/- 4.2 mmHg (28.6 +/- 3.4 mmHg in normal subjects (p less than 0.01)), mean IIi was 8.6 +/- 2.2 mmHg (15.8 +/- 2.7 mmHg in normal subjects (p less than 0.01)) and mean transcapillary colloid osmotic gradient (IIp-IIi) was 12.7 +/- 3.8 mmHg compared to 12.8 +/- 2.7 mmHg in normal subjects (p greater than 0.1). Mean PV was increased by 21% compared to normal values (p less than 0.01) and IFV increased by 43% (p less than 0.01). The study demonstrates that reduction in IIp in hepatic cirrhosis is accompanied by a decrease of IIi in subcutaneous tissue resulting in unchanged transcapillary colloid osmotic gradient. The reduction in IIi can partly be explained by simple dilution and partly by a decrease in interstitial protein mass. The wash-down of interstitial proteins in non-splanchnic tissues reduces the tendency to oedema and hypovolaemia.

Adult↗
PubMed1985

Dextran 70 versus donor plasma as colloid in open-heart surgery under extreme haemodilution.

Dextran 70 and donor plasma were compared as colloid in the priming solution during heart-lung perfusion in open-heart surgery. The patients underwent surgery for coronary artery or aortic valve disease. One group of nine patients had plasma in the priming solution, while ten patients received dextran 70. Prior to perfusion the patients in the dextran group received monovalent hapten to prevent anaphylactic reactions towards dextran. During the perfusion the same level of haemodilution was established in both groups; the haematocrit values fell from about 39 vol. per cent before perfusion to about 19 vol. per cent after 45 min of perfusion. Eighteen hours postoperatively, the haematocrit had increased to about 35 vol. per cent. The mean concentrations of total serum protein in preoperative samples from the plasma and dextran group were 66.0 g/l and 66.3 g/l, respectively, and fell to 42.6 g/l and 28.3 g/l in samples taken after 45 min of perfusion. The serum-protein concentration in the dextran group remained significantly lower than that of the plasma group throughout the postoperative period. A similar pattern was seen for the albumin concentration. Preoperatively the mean values of the colloid osmotic pressure of plasma were 24.2 mmHg and 25.5 mmHg in the plasma and dextran group, respectively. Corresponding figures 45 min after start of perfusion were 13.9 mmHg and 16.9 mmHg, respectively, significantly higher in the dextran group than in the plasma group. The colloid osmotic pressure exerted by dextran was about 9 mmHg during heart-lung perfusion and about 4 mmHg 18 h later.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve Insufficiency↗
PubMedDate not supplied

Functionality of protective colloids affecting the formation, size uniformity and morphology of drug-free polylactic acid microspheres.

Drug-free polylactic acid (PLA) microspheres were prepared by an emulsification-solvent evaporation technique using different types of protective colloids. The influence of five types of hydrophilic prolymers (polysaccharides, proteins, synthetic cellulose derivatives, synthetic nonionic polymers and surfactants) on the formation, size uniformity and morphology of PLA microspheres was investigated. Four characteristic functions (surface activity, viscosity, electric charge and interfacial film formation) of the hydrophilic polymer aqueous solutions were used to evaluate the efficacy of these protective colloids used. The results indicate that these four functions were the key parameters to achieve the formation of PLA microspheres. The best protective colloid should have high surface activity, optimum viscosity, adequate electric charge, and form an interfacial film to give a higher recovery, better size uniformity and smoother topography of the PLA microspheres.

Colloids↗
PubMed1989

The use of crystalloidal and colloidal solutions for volume replacement in hypovolemic shock.

A wide variety of colloidal and crystalloidal fluids, as well as blood and blood products, are available to the clinician for treatment of the hypovolemic patient. These fluids vary with respect to the size, shape, and concentrations of electrolytes, colloidal molecules, and/or cellular components, duration of volume-expanding effects, incidence of allergic reactions, and effect on the coagulation system. When these fluids are administered intravenously, their distribution in the vascular, interstitial, and cellular compartments can be predicted from fundamental physiological principles as well as from the results of laboratory and clinical research. It is thus recognized that colloidal fluids and blood provide more rapid expansion of the intravascular space when compared with crystalloidal fluids. Similar volumes of crystalloidal fluids more rapidly expand the interstitial and intracellular spaces. These principles guide therapy in hypovolemic shock. A logical decision regarding intravenous fluid therapy may be based on the nature of the volume deficit (blood, plasma, or selective protein loss, loss of free water and/or electrolytes) and the predicted changes in cellular and extracellular compartments.

Capillary Permeability↗
PubMed1979

Empty sella secondary to suprasellar colloid cyst of foregut (respiratory) origin. Case report.

An enlarged sella turcica was discovered in a 40-year-old man who had bitemporal headaches. A pneumoencephalograph revealed a third ventricular cyst, dilated lateral ventricles, and an empty sella. The colloid cyst was lined by foregut epithelium, probably originating in the respiratory tract, and dense connective tissue. This case is the first instance of an empty sella associated with a colloid cyst of the third ventricle. It is proposed that enlargement of the mass in the third ventricle caused increased pulsation pressure of the cerebrospinal fluid, and that in the presence of an incompetent diaphragma sellae the subarachnoid space expanded into the sella. The origin of third ventricle cysts is reconsidered. It is concluded that suprasellar colloid cysts may arise from endoderm, ectoderm, neuroepithelium, or a combination of these epithelia.

Adult↗
PubMed1994

Third ventricular xanthogranulomas clinically and radiologically mimicking colloid cysts. Report of two cases.

Two cases are reported of third ventricle masses that were clinically and radiographically indistinguishable from pure colloid cysts. A 21- and a 36-year-old man presented with a 5-year and 10-day histories of headache, respectively. Magnetic resonance (MR) imaging revealed smooth, homogeneous masses in the anterior third ventricle that were iso- to hyperintense on T1-weighted MR images and hyperintense on T2-weighted images. There was little enhancement with intravenous contrast material. In both patients, craniotomies were performed and histopathological examination revealed xanthogranulomas of the choroid plexus with only microscopic foci of colloid cyst-like structures. These cases illustrate that xanthogranulomas of the third ventricle may clinically and radiologically mimic pure colloid cysts, that a range of MR imaging signals can be seen, and that craniotomy rather than stereotactic aspiration is the indicated treatment.

Adult↗
PubMed1999

Rare occurrence of intracerebellar colloid cyst. Case report.

Colloid cysts are rare intracerebral lesions that are preferentially encountered within the third ventricle. There are only a few reports in which colloid cysts are described in other locations such as the fourth ventricle. A symptomatic intracerebellar colloid cyst in a 45-year-old woman is described. The patient presented with headache, gait disturbance, and nausea. Neuroradiological imaging revealed compression of the fourth ventricle, hydrocephalus, and an intracerebellar cystic lesion measuring 4 x 5 cm that had a small peripheral solid portion. The cyst was successfully removed via a paramedian suboccipital approach. Postoperatively, the patient recovered quickly. The findings in the present report represent an additional example of the broad spectrum of cystic lesions encountered in the cerebellum.

Cerebellar Diseases↗
PubMed1975

Elevated levels of colloid osmotic pressure in cecal contents of germfree animals.

Determinations of colloid osmotic pressure in the supernatant of germfree rat cecal contents indicated substantially elevated values in comparison to those of rat blood plasma or of conventional rat cecal supernatant. The germfree cecal supernatant, under conditions of similar total osmolality, was able to draw water at a sizable rate from a polyvinylpyrollidone solution whose colloid osmotic pressure was taken to be equivalent to that of interstitial fluid. It is suggested that the water absorption inhibition which was observed in the lower bowel of germfree rodents, is in part caused by the colloid osmotic pressure gradient which exists in these animals between the luminal contents and the tissue component.

Animals↗
PubMed1999

Over-the-counter drug products containing colloidal silver ingredients or silver salts. Department of Health and Human Services (HHS), Public Health Service (PHS), Food and Drug Administration (FDA). Final rule.

The Food and Drug Administration (FDA) is issuing a final rule establishing that all over-the-counter (OTC) drug products containing colloidal silver ingredients or silver salts for internal or external use are not generally recognized as safe and effective and are misbranded. FDA is issuing this final rule because many OTC drug products containing colloidal silver ingredients or silver salts are being marketed for numerous serious disease conditions and FDA is not aware of any substantial scientific evidence that supports the use of OTC colloidal silver ingredients or silver salts for these disease conditions.

Colloids↗
PubMed1979

[Contribution on standardisation of the colloidal iron binding reaction (author's transl)].

The iron binding reaction provides inconstant results with respect to the number of electron dense particles bound to cell surfaces if acetic acid has been used for the production of the colloid and for washing procedures in the course of iron binding. In the present paper it is shown that the dilution of colloidal iron hydroxide by adding acetic acid changes the size distribution of the colloidal particles, resulting in a marked decrease of iron binding. For that reason, a standard method is proposed in which hydrochloric acid is used instead of acetic acid. By this modification more reproducible results are gained with regard to the above mentioned quantitative aspects.

Animals↗
PubMed2002

Endoscopic resection of colloid cysts.

COLLOID CYSTS OFTEN cause cerebrospinal fluid pathway obstruction, which results in ventricular enlargement that provides sufficient space for endoscopy. Because of further improvement of endoscopic instrumentation and hemostasis, colloid cysts often can be resected completely via an endoscopic approach. This article describes our endoscopic technique as developed for the removal of colloid cysts located in the third ventricle.

Brain Diseases↗
PubMed2003

[The effects of colloid preload on hemodynamics and plasma concentration of atrial natriuretic peptide during spinal anesthesia in elderly patients].

We evaluated the effects of moderate colloid preloading on hemodynamics and plasma concentration of atrial natriuretic peptide (ANP) during spinal anesthesia in elderly patients undergoing low extremity surgery. Twenty patients (aged 66-90 yr) were randomly divided into two groups. Control group (n = 10) received no prehydration, and hydration group (n = 10) received colloid (6% hydroxyethyl starch; HES) preloading of 8 ml.kg-1 before spinal anesthesia. Systolic blood pressure decreased significantly 10 and 30 min after spinal anesthesia in either group, and there was no difference between the groups in the incidence of hypotension. The concentration of ANP decreased significantly by 23% in control group, whereas it increased significantly by 86% in hydration group, suggesting that cardiac preload might increase with volume expansion effect of prehydration with HES. In conclusion, colloid preloading with moderate volume might prevent the decrease in cardiac preload with increasing ANP, whereas it did not prevent spinal-induced hypotension in elderly patients.

Aged↗
PubMed2003

Radio-tympano-sinu-orthesis with 186Re-colloid: a new treatment modality for chronic otitis media and paranasal mucositis.

UNLABELLED: This preliminary treatment trial was performed to evaluate the safety and clinical efficacy of intracavitary therapy with (186)Re-colloid in patients with recurrent otitis media and paranasal sinusitis, resistant to pharmacotherapy and surgical treatment. METHODS: Thirty-nine applications of 5-35 MBq (186)Re-colloid into the tympanon and the paranasal sinuses were performed in 6 patients. Biodistribution and biokinetics were studied by gamma-camera imaging. Clinical success was documented 6-20 mo after therapy by each patient's self-evaluation and by rhinootologic follow-up, using a 4-step score. RESULTS: No harmful side effects were seen. There was good-to-excellent clinical improvement with a score of +1.44 +/- 0.5 by each patient's self-evaluation and by physicians scoring of +0.81 +/- 0.9 with only negligible extracranial tracer deposition. CONCLUSION: This novel treatment option using intracavitary application of (186)Re-colloid in chronic otitis media and sinusitis is safe and effective. The term "radio-tympano-sinu-orthesis" might be proposed analogously to the well-known radiosynoviorthesis.

Adult↗