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Biomedical subjects

T Horn

Publications and source records attributed to T Horn.

At least 181 records · Page 10Linked to original sources
PubMed1987

Serum aminoterminal type III procollagen peptide and the 7S domain of type IV collagen in patients with alcohol abuse. Relation to ultrastructural fibrosis in the acinar zone 3 and to serum hyaluronan.

Serum concentrations of the aminoterminal propeptide of type III procollagen and of the 7S domain of type IV collagen, presumed to reflect fibrotic activity in liver tissue, and of the glycosamonoglycan hyaluronan, were obtained from 40 alcohol abusers, at the time of liver biopsy. The serological results were related to morphological findings in liver tissue, i.e. no fibrosis, fibrosis without cirrhosis, micronodular cirrhosis and macronodular cirrhosis, and to ultrastructural indications of perisinusoidal fibrosis in the acinar zone 3. All patients with fibrosis and cirrhosis on light microscopy had elevated serum levels of the type III procollagen peptide as well as of the 7S domain of type IV collagen. However, due to a considerable overlap between the groups, no relations could be demonstrated to the severity of the fibrosis, supporting the assumption that these serological markers reflect the current fibrotic activity and not the amount of fibrotic tissue previously deposited. Among patients without fibrosis on light microscopy, a relation between the propeptide levels and ultrastructural perisinusoidal zone 3 fibrosis was observed, suggesting that type III procollagen peptide may be valuable in detecting very early liver fibrosis. A positive correlation was demonstrated between the serum concentrations of type III procollagen peptide and hyaluronan. As hyaluronan is degraded in the liver endothelial cells, it is suggested that the liver is involved, not only in the synthesis, but also in the degradation of the propeptide.

Adolescent↗
PubMed1987

Detection of early zone 3 liver fibrosis in chronic alcoholics. A comparison of four connective tissue staining methods.

Fibrous deposits in the perisinusoidal space in the acinar zone 3 are early and prognostically important features of the alcoholic liver lesion. Four connective tissue staining methods: van Gieson's Picro-Fuchsin (VG), Gordon & Sweets' reticulin (GS), Chromotrope Aniline Blue (CAB), and Picro-Sirius (PS) were evaluated concerning their relative sensitivity in the detection of early zone 3 fibrosis. A selected area in 60 liver biopsies with preserved architecture, obtained from chronic alcoholics, were studied. A semiquantitative registration of the degree of fibrosis was made. A comparison between the scores of the various staining methods by means of Pratt's test revealed PS to be significantly the most sensitive method. GS was insignificantly more sensitive than CAB while VG (which in contrast to the other three methods leaves reticulin unstained) was the least sensitive. In five biopsies which only revealed fibrosis in PS, perisinusoidal collagenization was confirmed by transmission electron microscopy. In the histological detection of early zone 3 fibrosis, PS is therefore recommended.

Alcoholism↗
PubMed1987

Renal oncocytoma.

Renal oncocytomas are usually regarded as benign tumors. Metastases from renal oncocytomas to regional and especially distant lymph nodes are extremely rare. This paper describes five cases of renal oncocytomas, one of which had a malignant behaviour with metastases to regional and distant lymph nodes.

Adenoma↗
PubMed1987

Electron microscopy of biopsies from bronchogenic neoplasms.

Bronchial biopsies were investigated by light microscopy (LM) and electron microscopy (EM) with the aim to evaluate if EM could contribute to the LM tumour type diagnosis. Fourty-three pairs of biopsies were comparable. A histogenetic typing, especially of light microscopically undifferentiated and unclassifiable carcinomas, was possible by EM. However, when considering the therapeutical possibilities, at present time, LM tumour classification must be regarded as fully sufficient.

Biopsy↗
PubMed1987

Influence of the prostaglandin E1 analogue Rioprostil on the human gastric mucosa.

Ten healthy volunteers received the prostaglandin E1 analogue Rioprostil 300 micrograms b.i.d. for 1 week. Endoscopically obtained biopsies were investigated with tritiated thymidine and autoradiography to determine the rate of cell proliferation and with a texture-analyzing system to measure the intracellular amount of mucus in the epithelial cells. Rioprostil did not alter the tritiated thymidine labeling index in the antral area but did significantly depress it in the fundic area. The mucus content was unchanged in the antrum but was significantly increased in the fundus. These observations indicate that Rioprostil given orally causes an enhanced cell maturation in the fundic area as well as an increased intracellular mucus content. Rioprostil seems to have no influence on the human antral area.

Adult↗
PubMed1987

Immature ovarian teratoma in a postmenopausal woman.

We report the first case of immature ovarian teratoma occurring after menopause in a 57-year-old, 3 years postmenopausal woman. Within one year after resection of the teratoma she developed peritoneal botryoid rhabdomyosarcoma, which probably originated from initially unrecognized rhabdomyoblasts in the teratoma. The patient died 6 months later from progressive disease after a transient adriamycin-induced tumor response. The literature on ovarian immature teratoma and ovarian rhabdomyosarcoma is briefly reviewed, and the available treatment is discussed.

Cyclophosphamide↗
PubMed1987

In vitro tetraploidy in patients with ulcerative colitis.

One hundred and seven patients (57 patients with ulcerative colitis and 50 controls) were investigated for in vitro tetraploidy (IVT) in dermal fibroblast monolayer cultures. There was no difference in incidence of IVT between patients with ulcerative colitis and controls. We advance the hypothesis that the genetic background of the colorectal cancer type found in ulcerative colitis differs from that found in the colon cancer syndromes and in non-hereditary colorectal cancers. Colorectal cancer in ulcerative colitis is probably only dependent on the degree of inflammatory lesions of the colonic mucosa.

Adolescent↗
PubMed1987

Lipofuscinosis of the human uterus.

A case of uterine lipofuscinosis in a patient with Friedreich's ataxia is described. Ultrastructural investigation confirmed the mitochondrial origin of the lipofuscin. Clinically, the patient suffered from brown bowel syndrome. Both the brown bowel syndrome and the uterine lipofuscinosis in the present case may be related to Friedreich's ataxia.

Adult↗
PubMed1987

Pityriasis rosea and the need for a serologic test for syphilis.

A rapid plasma reagin (RPR) test was performed in fifty patients with a clinical diagnosis of pityriasis rosea to determine the frequency of syphilis as the underlying cause of the eruption. In none of the fifty patients was syphilis the cause. Experience in diagnosing skin diseases, frequency of syphilis in the community served, and the characteristics of the individual eruption are important factors in the decision to perform an RPR test.

Adolescent↗
PubMed1986

Early alcoholic liver injury. Activation of lipocytes in acinar zone 3 and correlation to degree of collagen formation in the Disse space.

Acinar zone 3 areas in liver biopsy specimens from 23 alcoholics and 47 non-alcoholics were investigated by light microscopy and transmission electron microscopy to asses fibrosis in the perisinusoidal space and to evaluate the role of the lipocytes. Quantitative analysis by light microscopy on toluidine blue-stained sections showed a significant reduction in number of lipocytes--median values of 2.7 and 1.2 lipocytes per 100 hepatocytes in biopsies from chronic alcoholics showing no or varying degrees of zone 3 fibrosis, respectively, as compared to 3.6 lipocytes per 100 hepatocytes in non-alcoholic livers. By transmission electron microscopy, the reduction in number of lipocytes was related to a corresponding increase in number of cells rich in rough endoplasmic reticulum and microfilaments (activated lipocytes). The occurrence of activated cells was significantly correlated to fibrosis of the perisinusoidal space. Activation of lipocytes and collagenization of the perisinusoidal space appeared before light microscopic evidence of fibrosis and were topographically not related to Mallory bodies or alcoholic hepatitis.

Actin Cytoskeleton↗
PubMed1986

Scanning electron microscopy of immune complexes in membranous glomerulopathy.

Scanning electron microscopy (SEM) was done on seven cases of membranous glomerulopathy (MG) in order to describe the morphologic appearance of the immune complexes that are deposited in the glomerular basement membranes, as previous SEM studies on the human glomerulus primarily focused on the changes in the podocytes. The diagnosis of membranous glomerulopathy of idiopathic form or secondary to systemic lupus erythematosus was confirmed by conventional light and transmission electron microscopy and immunofluorescent microscopy. By SEM, the external surfaces of the basement membranes were covered by immune complexes that appeared as a network of "lumpy-bumpy" deposits. They were arranged in anastomosing cords imparting a "swiss cheese" pattern. The immune-complex nature of these anastomosing cords of deposits is confirmed by our preliminary immunoscanning electron-microscopic study. The exact mechanism for immune complexes to be localized on the external surface of the basement membrane remains to be elucidated.

Antigen-Antibody Complex↗
PubMed1986

A chemical 5'-phosphorylation of oligodeoxyribonucleotides.

To circumvent the use of T4 polynucleotide kinase and ATP for the 5'-phosphorylation of synthetic oligodeoxyribonucleotides after deprotection and purification, we have developed a new chemical phosphorylation reagent that can be used on automated DNA synthesis instruments. The phosphite-derived compound, bis(beta-cyanoethoxy)-N,N-diisopropylaminophosphine, is coupled to a solid-supported fragment and oxidized under the same conditions as nucleoside phosphoramidites. The resultant 5'-phosphate oligomer is then fully deprotected in standard ammonium hydroxide solution at elevated temperature. Reverse-phase, high-pressure liquid chromatography, silica thin-layer chromatography, and 31P-nuclear magnetic resonance spectra of chemically phosphorylated thymidine were compared with a variety of phosphorus derivatives of thymidine. All evidence suggested that the nucleoside was converted to the 5'-phosphate form quantitatively with the reagent. Moreover, an excellent enzymatic ligation reaction was obtained with a chemically phosphorylated oligonucleotide.

DNA Ligases↗
PubMed1986

Perfusion fixation of hepatic needle biopsies for scanning electron microscopy. A methodological study.

Perfusion fixation is essential for the examination of the hepatic microvasculature by scanning electron microscopy. No detailed study has previously been done on the perfusion of human hepatic needle biopsies. The present paper demonstrates two modifications of a simple technique by which needle biopsies can be perfused. Perfusion was performed either manually (n = 33) or with a constant perfusion pressure of 10-15 mm H2O (n = 54). No significant difference in the ultrastructural preservation was observed in the two groups. Manual perfusion, however, when done gently, was superior in cleaning the sinusoids, and thus larger areas could be investigated by this method. Topographical orientation was possible, allowing the identification of terminal hepatic veins and portal tracts.

Biopsy, Needle↗
PubMed1986

The sinusoidal lining cells in "normal" human liver. A scanning electron microscopic investigation.

The scanning electron microscopic was used to study the fenestrations of human liver sinusoids. Thirteen biopsies, where light microscopy and transmission electron microscopy revealed normal sinusoidal architecture, were investigated. The number of fenestrae was calculated in acinar zone 3 and acinar zone 1 areas. The porosity, i.e. fenestrated area relative to total area of the sinusoidal lining wall, was estimated on micrographs by using a Texture Analysing System (TAS). A zonal gradient was found with median 23.5 fenestrae per micron 2 in zone 3, as compared to 19.2 fenestrae per micron 2 in the zone 1 area (p less than 0.005). Increasing porosity towards the terminal hepatic vein was found (9.1% in zone 3 vs. 7.6% in zone 1 (p less than 0.05)). This was due to an increased number of fenestrae measuring 100 nm or less in diameter in zone 3 areas. The number of fenestrae measuring more than 100 nm but less than 300 nm was unchanged along the sinusoids. Fenestrae larger than 300 nm were rare and randomly distributed. The results suggest a different permeability along the sinusoidal lining, which may influence the transport between blood and hepatocytes and thus be of importance to hepatocellular function.

Adult↗
PubMed1986

The blood hepatocytic barrier: a light microscopical, transmission- and scanning electron microscopic study.

The normal blood hepatocytic barrier (BHB), comprised by the endothelial lining cells and the perisinusoidal space, was investigated, and it was concluded that the BHB is a complex structure in which each individual part serves several functions. Immunohistochemical staining for factor VIII showed endothelial lining cells to be positive. By TEM and SEM the endothelial cells were seen to be fenestrated without a basal lamina. They possess numerous endocytotic vesicles. The perisinusoidal space contains the lipocytes and a matrix composed of fibrils, and a microfilamentous to granular material. The nature of these matrix components was poorly analyzable by conventional methods. Lipocytes were visualized by LM in: sections stained with oil red 0 after fixation in Baker's formol-calcium and following post-fixation in dichromate, and toluidine-blue-stained Epon-embedded sections. TEM revealed numerous cytoplasmic processes rich in microfilaments encircling the sinusoids.

Azo Compounds↗
PubMed1986

[Contact dermatitis caused by 2-chloroacetophenone following tear gas exposure].

We report a case of acute contact dermatitis caused by exposure to 2-chloracetophenone tear gas in the face. Within 3 days the contact dermatitis had disappeared without medical treatment, but 7 days after exposure, a scaly pruritic eruption developed at the site of the original exposure although no new contact with 2-chloracetophenone had taken place.

Adult↗