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PubMed1987

Hypodense colloid cyst of the third ventricle.

The diagnosis of colloid cysts of the third ventricle using computed tomography (CT) rarely causes problems. The typical well-rounded, hyperdense mass in the anterior part of the third ventricle is usually well shown, along with the associated lateral ventricular dilatation. However, it is also well recognized that these cysts may be isodense, and this can on occasion lead to diagnostic difficulty. Rarely have hypodense colloid cysts been reported. We describe two patients in whom the low density of the tumors led, initially, to a failure to identify them on the CT scan. Although this is an atypical appearance, it is important to be aware of it, as colloid cysts which are surgically curable have a definite morbidity and mortality if untreated.

Adult↗

PubMed1987

Receptor-mediated binding, endocytosis and cellular processing of macromolecules conjugated with colloidal gold.

Receptor-mediated expression of cellular functions assures biological specificity, regulation, and control of nutritive and metabolic requirements. The study of receptor-ligand interactions is a central theme in many published reports employing colloidal gold labeling. With the ligand directly conjugated with colloidal gold, the investigator is afforded the opportunity to observe all phases of cellular binding, endocytosis, lysosomal delivery and catabolism. Reviewed are published studies employing direct ligand conjugation with colloidal gold, the relative merits and disadvantages of this type of procedure and data from recent studies investigating endothelial receptor binding of proteins in the coagulation and fibrinolysis cascades.

Animals↗

PubMed1987

Immunoglobulin IgM detected by ELISA in bovine pituitary intraglandular colloid, non-vascular holocrine secretion of intermediate lobe cells.

ELISA was employed to determine the presence of immunoglobulin IgM in crude bovine pituitary intraglandular colloid (IGC). The percentage weight of IgM was 1.15% per total weight of lyophilized colloid. The colloid from 32 glands (sufficient amount to perform the ELISA) was pooled and placed in 20 ml cold phosphate buffered saline (pH 7.6) and lyophilized. The total weight of the lyophilized material was 2.05 g IGC, housed in the intraglandular lumen (residual lumen). This is the holocrine secretion of the marginal half of bovine pituitary intermediate lobe (IL) cells, known to produce the ACTH/LPH family of peptides. The discovery of immunoglobulin IgM in IGC is a unique phenomenon. Since it has been established that IL cells process common precursor molecules to different final secretory products, it can be envisioned that continuing studies will help to elucidate the relationship between immunoglobulins and the ACTH/LPH family of peptides.

Animals↗

PubMed1987

Leukocyte labeling with technetium-99m tin colloids.

Triple density gradients of metrizamide in plasma (MP) were used to characterize label distribution in human leukocyte preparations incubated with 99mTc tin colloids. Less than 50% of the cell-associated radioactivity was specifically bound to leukocytes when heparinized blood was rotated with stannous fluoride colloid ([Tc]SFC). Labeling efficiency in leukocyte rich plasma (LRP) averaged 44%, of which greater than 90% was specifically bound to leukocytes. MP-gradient analysis also revealed that leukocyte labeling did not occur with stannous chloride colloid, nor when citrate was present during rotation with [Tc]SFC. When citrate was added after labeling to "solubilize" unbound [Tc]SFC, radiocolloid was removed from the leukocytes, indicating that the mechanism of [Tc]SFC labeling is adherence rather than phagocytosis. Technetium-labeled neutrophils exhibited normal in vitro chemotaxis and no lung uptake in vivo. Technetium-labeled mononuclear leukocytes, on the other hand, exhibited prolonged lung transit in vivo. Neither [Tc]SFC cell preparation showed signs of in vivo reoxidation to pertechnetate.

Humans↗

PubMed1986

Studies on hepatobiliary lymph flow with radioactive colloid--for lymph node metastasis resection of carcinoma of the bifurcation of hepatic duct.

Hepatobiliary lymphoscintigraphy by Technetium 99m-rhenium colloid (99mTc-Re colloid) using a fine needle guided by ultrasonography was performed on 12 patients who underwent resection of the hepatoduodenal ligament lymph nodes. Histological examination revealed no lymph node metastasis in 8 patients. In 4 patients in whom 99mTc-Re colloid was injected into the left medial inferior hepatic segment, periarterial lymph nodes showed higher isotope uptake count than periductal nodes, and lymph nodes around the common hepatic artery revealed higher values than superior posterior pancreatoduodenal nodes. On the contrary, in 3 patients in whom the isotope was injected into the right anterior inferior segment, periductal lymph nodes had higher values than periarterial nodes, and superior posterior pancreatoduodenal lymph nodes showed higher values than those around the common hepatic artery. In one patient in whom the isotope was injected into both right and left segments, superior posterior pancreatoduodenal lymph nodes showed similar values to those around the common hepatic artery. Periportal lymph nodes tended to have values between those of periarterial and periductal ones. Lymph node metastases were confirmed in 4 patients in whom the relationships mentioned above was not always observed, and periportal lymph nodes showed the highest values among the three.

Adenocarcinoma↗

PubMed1985

Dual ultrastructural localization of two neurotransmitter-related antigens: colloidal gold-labeled neurophysin-immunoreactive supraoptic neurons receive peroxidase-labeled glutamate decarboxylase- or gold-labeled GABA-immunoreactive synapses.

To study the morphological substrate for interaction between two chemically distinct neuronal types, two double ultrastructural immunolabeling strategies were employed. In the first, two different electron-dense markers were used to examine simultaneously two different neurotransmitter-related antigens in the hypothalamic supraoptic nucleus in the same thin section. Results obtained with the first method were confirmed with a second approach based on postembedding immunostaining of alternate serial thin sections with different antisera. Antiserum against glutamate decarboxylase, the enzyme responsible for the synthesis of the inhibitory amino acid transmitter gamma-aminobutyric acid (GABA), or antisera against GABA, was used to localize immunoreactive axons in the hypothalamic supraoptic nucleus. With light microscopy, glutamate decarboxylase- and GABA-immunoreactive axon terminals immunostained with peroxidase were found arborizing throughout all areas of the nucleus; terminal boutons were found adjacent to unlabeled somata within the nucleus. Cells containing immunoreactive oxytocin, vasopressin, and neurophysin were localized with peroxidase. Glutamate decarboxylase-immunoreactive axons stained with peroxidase prior to embedding in plastic were demonstrated to contact neurons which contained vesicles immunostained with neurophysin antiserum by a post-embedding immunocytochemical procedure which used immunoglobulins or protein A adsorbed to colloidal gold as a second ultrastructural marker. Quantitative evaluation of post-embedding staining with colloidal gold using a neurophysin primary antiserum indicated a specific antigen localization in neurosecretory vesicles. A critical factor in this double-labeling paradigm was that immunological reagents used in the second series did not cross-react with those used in the first series, regardless of the species of origin of antisera. To provide further verification of GABAergic synapses on neurophysin-containing neurons, alternate serial ultrathin sections were stained with colloidal gold using antisera against either neurophysin or GABA; boutons immunoreactive for GABA made synaptic contact with supraoptic neurons containing neurophysin immunoreactivity. Converging results obtained with these two procedures indicate that GABAergic axons synapse directly on neurons containing oxytocin or vasopressin in the rat hypothalamic supraoptic nucleus.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1981

[Human albumin or dextran 60 for the restoration of the blood volume, with special reference to the colloid osmotic pressure (author's transl)].

The high cost and limited availability of human albumin as a plasma substitute make it desirable to limit its use to special cases and to replace it by inexpensive and easily obtainable colloids. Patients about to undergo major abdominal surgery were given either human albumin or dextran 60 during the operation and for three days afterwards. Although both groups received the same quantity of colloidal plasma substitutes they differed significantly in respect to the serum albumin and protein concentrations. However, the osmotic pressure, for the maintenance of which the albumin fraction is mainly responsible, showed a marked fall in both groups, indicating that human albumin is not superior to dextran. All other parameters, particularly the clotting mechanism, remained within the normal range and did not differ between the two groups. The results of the study, in conjunction with the known facts regarding the metabolism and function of albumin, suggest that dextran 60 can adequately replace human albumin in a large number of cases. Great importance belongs to measurement of the colloid osmotic pressure.

Blood Proteins↗

PubMed1982

Colloidal bismuth subcitrate tablets and placebo in chronic duodenal ulceration: a double-blind, randomised trial.

In a double-blind, randomised trial of 46 outpatients with endoscopically proven chronic duodenal ulceration, 22 were given colloidal bismuth subcitrate (De-Nol, Gist-Brocades) and 24 were given placebo for four weeks. Clinical and laboratory assessment was made after two and four weeks' therapy. Endoscopic healing was demonstrated in 86.5% of patients taking colloidal bismuth tablets and in 25% of patients taking placebo. We observed no clinical or biochemical side effects in either group. These results indicate that colloidal bismuth subcitrate tablets are well tolerated, and are effective in healing chronic duodenal ulcers.

Adult↗

PubMedDate not supplied

Digital cell image analysis of Feulgen-stained nuclei from human papillary, medullary, colloid, lobular and comedocarcinomas of the breast.

The morphonuclear characteristics (nuclear size and chromatin pattern), the proliferation index and the ploidy level were characterized in a series of 46 breast tumors including medullary (5 cases), papillary (6 cases), lobular (27 cases), colloid (4 cases) and comedo- (4 cases) carcinomas. The quantitative assessments were carried out by means of digital cell image analyses of Feulgen-stained nuclei from imprint smears. The results show that monovariate analyses (one-way variance analyses) were much less potent than multivariate analyses (principal components analyses followed by the canonical transformation of the data and discriminant analyses) in assessing the morphonuclear characteristics of these breast tumors. The multivariate analyses indicated that there might be a level of malignancy which increases according to the sequence papillary and medullary and colloid carcinomas-->comedocarcinomas-->lobular carcinomas. This assertion is corroborated by the ploidy-level-related results which revealed a higher proportion of highly aneuploid cases in the group of lobular carcinomas than in the group which included medullary, papillary and colloid carcinomas. However, since highly aneuploid cases were also encountered in this latter low malignancy level group, we expressed the hypothesis firstly that aneuploidy reflects two distinct biological properties, i.e. the aggressiveness of a tumor and its age, and secondly that a highly aneuploid but low malignancy tumor should correspond to old degenerating tumors.

Adenocarcinoma, Mucinous↗

PubMed1995

Immuno-colloidal gold labeled surface replica, and its application to detect sp56, the egg recognition and binding protein, on the mouse spermatozoon.

Using immuno-colloidal gold surface replicas (IGSR), we developed a method to demonstrate surface antigens in a whole view of a cell at the EM level. In this study, a monoclonal antibody (MAB) 7C5 directed against sp56, which is a mouse sperm protein (M(r) = 56,000 daltons) and has specific affinity for the zona pellucida, was used as primary antibody. Fixed mouse spermatozoa were incubated with primary antibody and colloidal gold-labeled secondary antibody on a slide glass. Used gold particles were 10, 20 or 30 nm in diameter. The spermatozoa were then critical point dried, and replicated with platinum and carbon. Replicas were examined with a transmission EM. The result suggests that sp56 is located on the outer surface of the plasma membrane covering approximately 2/3 of dorsal edge of the sperm head, but it is virtually absent in the tapered apical tip. When 10 and 20 nm colloidal particles were used, about 500 particles were observed on one side of the flat sperm head. Although the large 30 nm particles were easily recognized in low magnification figures, the attached number on the sperm head was generally lower than the number of 10 or 20 nm particles observed. By this method, we could effectively demonstrate the localization of a surface antigen in a wide cell view with clear landmarks.

Animals↗

PubMed1996

Colloid cyst of the third ventricle.

BACKGROUND: Colloid cyst of the third ventricle has rarely been reported in the ophthalmic literature. The incidence is about one per 1000 in asymptomatic patients and accounts for 0.55 to 2 percent of all intracranial tumors. Although it is an uncommon benign tumor, nearly half of symptomatic patients present with papilledema and hydrocephalus. Consideration of this intracranial tumor should be included in the differential diagnosis of papilledema and apparent unilateral disc edema. METHODS: A patient with highly asymmetrical papilledema and vague visual symptomatology involving the right eye was studied. Computer axial tomography (CT) without contrast enhancement revealed a colloid cyst of the third ventricle. Typical symptoms of the condition include headaches, nausea, vomiting, visual obscuration, transient diplopia and weakness of the lower extremities, which are due to acute hydrocephalus caused by increased intracranial pressure from cystic obstruction of the foramen of Monro. Intermittency of symptoms is characteristic of this lesion. RESULTS: The patient underwent frontal craniotomy with total tumor excision and reopening of the cerebrospinal fluid pathway. CONCLUSIONS: Colloid cyst of the third ventricle discovered incidentally on CT in asymptomatic patients with no evidence of hydrocephalus can be monitored periodically. If symptomatic, neurosurgery is usually indicated since prolonged increased intracranial pressure can lead to mental and physical deterioration as well as sudden death.

Brain Diseases↗

PubMed1997

Impact of lymphoscintigraphy on sentinel node identification with technetium-99m-colloidal albumin in breast cancer.

UNLABELLED: Identification of the sentinel node by using colloidal tracers and a gamma probe or lymphoscintigraphy could be an effective alternative for the complicated original dye-oriented approach. We studied the sentinel node detection rate using early and delayed imaging in breast cancer patients. METHODS: Thirty-seven patients were imaged 2 hr and 18 hr after peritumoral injection of 99mTc-colloidal albumin. Preoperatively, axillary foci were located with a handheld gamma probe that was also used to isolate radiolabeled nodes from the axillary dissection specimens. The predictive value of the sentinel node for the axillary tumorstatus was evaluated with histological examination. RESULTS: Two and 18 hr after injection, lymphoscintigraphy revealed one to three separate axillary lymph nodes in 33 and 34 patients, respectively. In 30 patients the axillary foci were easily localized with the gamma probe preoperatively. In all 34 patients (92%), with visualized axillary foci, at least one radioactive sample could be retrieved using the gamma probe (total 53 samples). Metastases were found in the sentinel nodes of 11 patients, in seven of 11 being the only tumor-positive lymph node in the axilla. There were no false-negative sentinel nodes. CONCLUSION: The selective targeting and prolonged intranodal retention of 99mTc-colloidal albumin allows successful sentinel node identification in most (92%) patients.

Aged↗

PubMedDate not supplied

[Colloid cysts of the third ventricle].

The authors analyze the results of surgical treatment of 51 consecutive patients with colloid cysts of the third ventricle. Patients were operated by the senior author from 1981 to 1996. Provided are the clinical signs, CT and MRI diagnostic criteria. Surgical treatment of colloid cysts is discussed in every detail. The authors believe, transcallosal approach with cyst enucleation via foramen of Monroe is the most adequate technique. No complications related to surgery were observed, except for transitory fixational amnesia, which completely regressed by 2-3 weeks postoperatively. The conclusion is that transcallosal approach with subsequent removal of the colloid cyst via the foramen of Monroe is a safe and reliable technique bringing no surgical complications.

Adolescent↗

PubMed1997

The subcellular localisation and the time course of bismuth in the gastric mucosa of rats after short-term administration of colloidal bismuth subcitrate.

The aim of this study was to investigate if colloidal bismuth subcitrate (CBS) can penetrate the gastric mucus barrier to reach the different sites of the antral mucosa and to estimate the time course for CBS to reach and remain in the mucosa. A single dose of CBS was administered orally to rats that were sacrificed at different time intervals post treatment. The control group received gum acacia without CBS. Colloidal bismuth subcitrate, visualised as electron dense precipitate (EDP), was seen in the gastric mucus layer, intercellular spaces and intracellularly after 30 minutes and disappeared after 6 hours. Scant amounts of EDP were observed in the gastric crypts, confined only to the upper parts of these structures. We concluded that CBS can penetrate the mucus and has a wide but uneven distribution in the gastric mucosa. Colloidal bismuth subcitrate, in the concentration given only penetrated the upper two-thirds of gastric pits and not the lower one-third. We also concluded that CBS has to be given 6 hourly to ensure its continuous presence in the gastric mucosa.

Animals↗

PubMed1976

["Colloid cyst" of the lateral ventricle--report of a case (author's transl)].

Colloid cyst is a relatively rare benign tumor which is usually found in the third ventricle. A patient who had a "colloid cyst" in his right lateral ventricle was experienced. A 33-year-old man had suffered from intermittent attacks of headache and vomiting for five months. On July 22, 1974, he was hospitalized to our clinic because of headache, memory and gait disturbance. At the time of admission his consciousness was clear but he had slight memory disturbance and urinary incontinence. Incipient papilledma was noted and the deep tendon reflexes of the lower extrimities were slightly accentuated. Lumbar puncture revealed a clear CSF and its pressure was within normal limit and the protein was 59 mg/dl. The plain skull films showed no abnormal findings. EEG showed an asymmetry of alpha-wave, and paroxysmal high voltage of slow wave was found in the right frontal area. Right cerebral angiography demonstrated an unrolling of the pericallosal arteries suggesting dilatation of the lateral ventricles. On the 9th hospital day, he suddenly began to complain of severe headache and became drowsy. Mannitol and hydrocortisone were injected intravenously without producing any remarkable effects. A ventricular drainage was done, and the patient recovered rapidly. A conray ventriculography revealed a round filling defect in the right lateral ventricle. A transventricular approach through a short linear incision in the right frontal cortex was preformed on the 25th hospital day. A cyst containing colloid substance, about 5x4 cm in size, was found to be attached to the medial wall of the right lateral ventricle anterior to the foramen of Monro. This cyst was almost completely removed. Histological findings revealed inner lining of epithelial cells, He died on the 25th postoperative day from bacterial meningitis. Autopsy confirmed the cyst to have originated from the right lateral ventricle. A review of the literature was made and the pathogenesis and diagnosis of this disease and the mechanism of development of the symptoms were discussed.

Adult↗

PubMed1962

An electron microscopic study of the passage of colloidal particles from the blood vessels of the ciliary processes and choroid plexus of the rabbit.

The thinnest areas of the capillaries of the choroid plexus and ciliary processes in the eye of the rabbit are characterized by the presence of fenestrae. When various colloidal particles opaque to the electron beam (thorotrast, gold sol, and saccharated iron oxide) were injected into the blood stream, none were found in fenestrae or in areas that might suggest their having passed through fenestrae. The passage of marker particles from the lumen to the surrounding connective tissue does take place on occasion in the areas of thicker walls in the capillaries and venules rather than in the attenuated and fenestrated endothelial walls. The pathway taken by these markers may be either through the cytoplasm of the endothelial cells via membrane-bounded vesicles and vacuoles or through the intercellular spaces of the vessels. An altered aqueous humor (cloudy and plasmoid) was produced by endotoxin injection or by making a draining fistula in rabbit cornea. Both methods gave rise to the same changes in the blood vessels of the ciliary processes. Under such conditions of inflammation the passage of colloidal particles through the thicker walls of the capillaries and venules was greatly increased and occurred primarily as an intercellular passage between the endothelial cells. The attenuated and fenestrated areas of the endothelium of the small capillaries remained unchanged with no particles passing through them. These results on the altered vessels of the ciliary processes parallel those of Majno and Palade (26) on the rat cremaster muscle.

Animals↗

PubMed1962

Studies on the cornea. III. The fine structure of the frog cornea and the uptake and transport of colloidal particles by the cornea in vivo.

The fine structure of the frog cornea has been studied and compared with that of the rabbit cornea (1, 2) particularly in relation to the uptake and transport of colloidal particles. The frog corneal endothelium does not possess a terminal bar and the fluid space of the intercellular space is apparently continuous with that of the anterior chamber. Colloidal markers (ThO(2), Fe(2)O(3)) placed in the anterior chamber pass down the intercellular space into the cornea. Markers injected intrastromally diffuse freely in the stroma and Descemet's membrane but pass across the endothelium only via membrane-bounded vesicles. These results are compared with those of similar experiments in the rabbit and it is concluded that the primary pathway for the passage of materials into the cornea is intercellular and that the pinocytotic pathway of the rabbit corneal endothelium (Kaye and Pappas; Kaye et al.) is an adaptation to the presence of a terminal bar. The significance of the separation of inward and outward pathways in terms of corneal metabolism is considered.

Animals↗

PubMed1995

Filtered technetium-99m-sulfur colloid evaluated for lymphoscintigraphy.

UNLABELLED: Several 99mTc-labeled radiopharmaceuticals have been developed for lymphoscintigraphy of the extremities. In the United States, however, these agents are not widely used clinically. This study evaluates the use of smaller particle sizes ( < 0.1 micron) of 99mTc-sulfur colloid (99mTc-SC) for lymphoscintigraphy. METHODS: The 99mTc-SC was prepared by kit, and the final preparation was filtered through a sterile 0.1-micron filter. The radiochemical purity (RCP) of the filtered 99mTc-SC was determined before administration. Nineteen patients with suspected lymphedema were injected with 18.5 MBq (500 muCi) filtered 99mTc-SC intradermally in each foot, and whole-body images were obtained immediately and 1, 3, 6 and 24 hr later. Local views over the inguinal or axillary lymph nodes were also obtained every 5 min for the first hour. RESULTS: The average RCP value was 93.4% +/- 4.2% (n = 19), and the RCP difference pre- and postfiltration of the 99mTc-SC preparation was -1.7% +/- 1.4% (n = 40). Evaluation of the particle size with the polycarbonate filter showed that 89.9% +/- 4.5% (n = 28) of particles were less than 50 nm, and the particle size was further determined by electron microscopy to be 38.0 +/- 3.3 nm (n = 202). The mean particle sizes of two peaks measured by laser light scattering techniques were 7.5 and 53.9 nm (major peak). Clinical studies with filtered 99mTc-SC demonstrated similar lymphoscintigrams compared with those obtained with 99mTc antimony sulfide colloid (99mTc-ATC). Filtered 99mTc-SC showed a faster transport rate to the inguinal lymph nodes and lower radiation dosimetry for liver, spleen and whole body compared with 99mTc-ATC. CONCLUSION: Filtered 99mTc-SC can be easily prepared and is readily available for routine clinical use in lymphoscintigraphic studies.

Antimony↗