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Y Collan

Publications and source records attributed to Y Collan.

At least 163 records · Page 9Linked to original sources
PubMed1981

Studies on the pathogenesis of ischemic cell injury. VI. Mitochondrial flocculent densities in autolysis.

Flocculent densities in the matrix of mitochondria have become quite important in cell pathology since, when prominent, they indicate irreversible cell injury. The morphology and chemical nature of these flocculent densities have been studied in Kidney after various periods of autolysis in vitro in whole tissue samples and in isolated mitochondria. After 30 to 60 min of ischemia, flocculent densities were seen only occasionally and they were most prominent in samples subjected to mechanical damage during isolation. However, in 2- and 4-h samples numerous densities were seen. The size of the densities increased with time, being about 1,400 A in diameter at 4 h. Densities were also seen in mitochondria isolated in medium containing EDTA. They were seen only in the mitochondrial matrix, and could occasionally be found in condensed mitochondria. Small densities were generally round but larger one varied in shape and often appeared as aggregates of smaller densities. Digestion of the densities from water-soluble glycol methacrylate embedded samples was successful with pronase, but neither acid nor lipid solvents were effective. calcium or inorganic phosphate content of isolated mitochondria did not show an increase parallel to the occurrence of flocculent densities. The results suggest that the densities consist predominantly of protein and are probably formed through denaturation of proteins of the mitochondrial matrix and/or the inner membrane.

Animals↗
PubMed1981

Lysozyme in neoplastic Paneth cells of a jejunal adenocarcinoma.

This is the first reported case in which neoplastic cells not of granulocytic or monocytic origin have been shown to contain lysozyme. A highly differentiated metastasizing adenocarcinoma of the jejunum is presented. Areas of the tumour contained cells resembling Paneth cells, that is, they contained cytoplasmic granules with 1) stained red with Masson's trichrome and 2) were shown to contain lysozyme by an immunoperoxidase technique. No argentaffin cells could be identified within the tumour. Staining of mucosubstance revealed large intestine-type sulfated glycoproteins in the tumour tissue. The presence of lysozyme-containing neoplastic Paneth cells suggests that the tumor: 1) originated from the mucosal crypts, and 2) had a high degree of cellular differentiation.

Adenocarcinoma↗
PubMed1981

Fabry's disease and cornea verticillata. A report of 3 cases.

Fabry's disease is a rare familial disorder of glycolipid metabolism which is caused by a deficiency of a lysosomal enzyme alpha-galactosidase. A Finnish family is described in which cornea verticillata was found in the father and 2 daughters. In all cases, there were symptoms suggesting Fabry's disease: febrile episodes the origin of which was not clear, limb pains and, in the case of the father, 20 years of proteinuria with elevated ESR, and hemiplegia and aphasia following a cerebral thrombosis at the age of 43. The diagnosis was confirmed by demonstration of an alpha-galactosidase deficit in the serum and urine of all patients. Deficiency of this enzyme leads to abnormally high urinary tri- and dihexosyl ceramide levels, and this was observed in the father and the elder daughter. At the age of 12, the daughter had loss of vision in her right eye as a result of occlusion of the central retinal artery. Electron microscopic (EM) examination of the father's dermal angioma suggested Fabry's disease. Computerized cranial tomography of the father revealed not only the cerebrovascular condition but also a disease affecting the white matter of the brain.

Adolescent↗
PubMed1980

Changes in mitochondrial lipids of rat kidney during ischemia.

Lipid changes in mitochondria isolated from rat kidney after various periods of ischemia were analysed by thin-layer chromatography and gas-liquid chromatography. Free fatty acids were increased at 30 min and more so thereafter. Total phospholipid fatty acids decreased steadily. The proportion of diphosphatidylglycerol (cardiolipin) in the total phospholipid fraction decreased at 30 min, but the proportion of phosphatidylcholine and phosphatidylethanolamine in the total phospholipid fraction did not change until the irreversible phase of ischemic injury. We have shown that decrease of cardiolipin in mitochondrial membrane occurs early during ischemia, and only during the irreversible phase of ischemia are phosphatidylethanolamine and phosphatidylcholine broken down. It is postulated that these phenomena are due to activation of phospholipase in the mitochondrial membrane.

Animals↗
PubMed1980

The cochlear nerve in Meniere's disease.

Cochlear nerves of 11 patients with advanced Meniere's disease were studied by light and electron microscopy. All the nerves appeared normal on light microscopy. In cross sections, the density of myelinated nerve fibers was approximately 20,000 fibers per square millimeter in most cases. In two cases, the density was reduced, about 14,000/sq mm. No correlation was found between the age of patients or the duration of the disease and the density of myelinated nerve fibers. On electron microscopy, there were several features that suggested primary axonal degeneration or segmental demyelination in the cochlear nerve.

Age Factors↗
PubMed1980

Vestibular nerve in Meniere's disease.

Biopsy specimens of vestibular nerves of 40 patients with severe Meniere's disease were studied by microscopy. In 17 patients, a translabyrinthine eighth nerve transection was done; in 23 patients, a middle fossa vestibular neurectomy was done. Many of the nerve fibers had thickened and deformed myelin coats; some were thinly myelinated fibers and some showed degraded myelin. No macrophages were present. Occasional vestibular ganglion cells had thin myelin coats. In six patients, there were lighter areas between the fibers. In these there were roughly parallel astrocyte processes, with numerous cytoplasmic filaments. The light areas were surrounded by a basement membrane. Four of these patients showed continuation of vertiginous symptoms after operation and were not helped by surgery. These patients may suffer from a neuropathy that is different from the more common causes of Meniere's disease.

Adult↗
PubMed1980

Vestibular findings in patients with acoustic neurinoma.

We studied the vestibular system of 30 patients with eighth nerve schwannoma. Preoperatively, cold and warm calorizations were performed. At operation, the utriculus and the ampulla of the horizontal semicircular canal as well as the eighth nerve were identified and removed for study. The sensory epithelium of utricular macula and ampullar crista appeared fairly normal in most cases. In one, there was tumor invasion to the labyrinth and in another patchy necrosis of the sensory epithelium. The number and quality of sensory cells varied from case to case. In cases with intact superior vestibular nerve, on light microscopy the histopathologic features of sensory epithelia did not differentiate between groups and symmetrical caloric reactions and with reduced or absent caloric reactions.

Adult↗
PubMed1980

Neuroglial tissue in human eighth nerve specimens.

One hundred eighty nerve biopsy specimens from patients with eighth nerve tumors or other vertiginous diseases requiring vestibular neurectomy were studied. In many specimens light microscopy revealed pale areas among the myelinated nerve fibers in the neurolemmal portion of the eighth nerve. Electron microscopy showed that these were ectopic areas of glial tissue consisting of bundles of numerous cytoplasmic processes of fibrous astrocytes. The abundance of filaments within each process and the occurrence of microtubuli suggest that these processes are reactive astrocytes and accordingly are present as a consequence of the reparative potential of the astroglial tissue after a neuronal lesion. The possible functional significance of the findings is discussed.

Astrocytes↗
PubMed1980

The combined toxicity of technical grade xylene and ethanol in the rat.

1. Inhalation exposure to xylene of technical grade (300 p.p.m. in air, 6 h a day, 5 days a week, up to 18 weeks) enhanced the overall mono-oxygenation reactions (7-ethoxycoumarin O-deethylase and 2,5-diphenyloxazole hydroxylase( as well as the UDP-glucuronyltransferase activity in rat liver microsomes. 2. The simultaneous ingestion of aqueous 15-20% ethanol as drinking fluid increased the cytochrome P-450 concn. and the mono-oxygenation activity even more than the xylene exposure alone. 3. Xylene-ethanol treatment resulted in additive or less than additive effects on the measured hepatic enzyme activities. 4. Renal ethoxycoumarin deethylase activity was enhanced both by ethanol ingestion and by xylene inhalation, and the response was additive after the combined exposure. 5. Liver histology revealed that even though the xylene exposure alone did not produce detectable liver damage, the xylene-ethanol treatment produced more severe liver damage than did ethanol ingestion alone.

Animals↗
PubMed1979

Vestibular sensory epithelium in Meniere's disease.

Utricle and horizontal semicircular canal ampulla removed during labyrinthectomy from 11 patients with advanced Meniere's disease were studied under light and electron microscope. In light microscopy the epithelium of both sensory areas appeared fairly normal. Many sensory cells revealed fluid-filled crescents at the nucleus and many cells were extensively vacuolated. Ultrastructurally, a part of the observations were apparently artifacts due to specimen handling; some were normal, age-related findings. Some changes were considered secondary to dilation of the endolymphatic space. True signs of degeneration, seldom seen in these specimens were intraepithelial cysts, necrotic cells, and dark homogeneous masses in the sensory epithelium and dilated nerve fibers in the subepithelial tissue. No general degeneration of the utricular macula or ampullar crista seems to occur in Meniere's disease.

Adult↗
PubMed1979

Immunohistochemical identification of renal lysozyme during allograft rejection in man.

An immunoperoxidase staining method was used to identify lysozyme in biopsy or transplantectomy specimens of human renal allografts during reversible and irreversible rejection of the grafts. Proximal tubules in apparently functioning nephrons showed lysozyme staining. In irreversibly rejected grafts, infiltrating mononuclear phagocytes in and near peritubular and glomerular capillaries also stained intensely for lysozyme. In acute necrotizing arteritis, lysozyme-positive cells (mononuclear phagocytes) infiltrated the blood vessel wall. The presence of infiltrating lysozyme-positive cells in the transplant was consistent with poor graft survival. The variation in lysozyme staining of proximal tubular cells apparently was a reflection of the differences in the reabsorption capacity of the tubular cells, attributable to the tubular dysfunction of renal allografts. The infiltrating lysozyme-positive cells probably contribute to the increased urinary excretion of lysozyme during acute rejection.

Adolescent↗
PubMed1979

Electron microscopy of nephropathia epidemica cell nuclei in kidney biopsies.

Ultrastructural changes in cell nuclei were studied in kidney biopsies from 18 patients suffering from Nephropathia epidemica. Three patients showed small nuclear particles in a large aggregate in a few cells of the distal tubule. The particles had a diameter of about 30 nm and their occurrence was not associated with intravenous glucose infusions. Large light nuclear bodies were numerous in the nuclei of both interstitial and tubular cells. Many showed strands of darker material about 35 nm in diameter at their center. Nuclear vesicles with varying amounts of membrane debris were seen in both tubular and interstitial cells. Occasional interstitial lymphocytes showed abnormal margination of chromatin. Of the changes observed the small nuclear particles are not found in kidney biopsies in other conditions and it is possible that they are aggregates of viral protein.

Cell Nucleus↗
PubMed1979

Selective vitamin B12 malabsorption with proteinuria. Renal biopsy study.

Percutaneous renal biopsy were performed on 5 patients with selective vitamin B12 malabsorption of whom 3 had proteinuria. Light microscopy showed slight prominence of the mesangial areas but otherwise the findings were normal. Electron microscopy showed increased mesangial matrix, thickening of the basement membrane at the mesangial areas and dark mesangial deposit. Light flocculent subendothelial material, moon craters, membranous convoluted structures, extracellular round particles and occasional intracellular microtubular inclusions were also seen in the glomeruli. The tubular basement membrane appeared thickened around a few tubules, showing membranous vesicular debris and convoluted structures. The capsular membrane also showed vesicular debris. On immunohistochemical examination the glomerular deposits contained immunoglobulins but not complement - an argument against their immunological nature. Deposits were seen only in patients who had been on inadequate treatment for years before the biopsy. Adequate treatment after correct diagnosis decreased the amount of deposits. Proteinuria did not apparently depend on the presence of glomerular deposits.

Adolescent↗
PubMed1979

Menière's disease: morphological findings in eighth nerve and vestibular end organs.

37 patients with advanced Menière's disease were operated on by translabyrinthine 8th nerve neurectomy or middle fossa vestibular neurectomy. Cochlear and vestibular nerves, epithelia of the utricular macula and ampullar crista of horizontal canal were studied. All specimens were fairly well preserved and the microscopic studies suggested that there is no general deterioration of these structures even in long-standing, advanced Menière's disease, but some minor deviations from normal are present in individual cells.

Adult↗
PubMed1979

Functional and histological findings in acoustic neuroma.

27 patients with acoustic neuroma were operated on by translabyrinthine tumor removal. At operation 8th nerve compartments were identified and removed for study. Results of the audiological test battery and vestibular tests were compared with histological state of the nerve specimens studied. The tumor appears only seldom to invade the cochlear nerve in cases with 'cochlear' hearing loss, but in the majority of cases with 'retrocochlear' hearing loss the cochlear nerve is invaded.

Cochlear Nerve↗
PubMed1979

Histological grading of transitional cell tumours of the bladder. Value of histological grading (WHO) in prognosis.

Mortality among 139 patients with transitional cell tumour of the bladder was studied. Tumours were reevaluated according to the grading system recommended by WHO. The absolute 5-year survival of histologically benign papilloma cases was 68%, of grade I carcinoma cases 64%, of grade II carcinoma cases 42% and of grade III carcinoma patients 34%. Clinical staging (UICC), however, would have been more effective than histological grading (WHO) for prognostic purposes. 3 of the 14 patients with histologically benign papilloma in this study developed grade I carcinoma during follow-up periods of between 4.5 and 24 years. Following radical treatment all recurrences were papillomas. The study suggests that histological grading should be used to complement clinical staging in prognosis and that with half-yearly check-ups and elimination of any tumours thus detected, patients with papilloma rarely develop carcinomas of higher grade than grade I.

Aged↗