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M Ortmann

Publications and source records attributed to M Ortmann.

33 records · Page 2Linked to original sources
PubMed1989

[Lectin histochemistry in the kidney and renal tumors].

In recent years histochemical methods using lectins with diverse carbohydrate binding specificities have proved useful tools for studying the distribution pattern of intracellular and pericellular glycoconjugates at the tissue level. Several studies of human kidneys have shown that the binding sites for certain lectins are strictly confined to various parts of the nephron. This allows the use of lectins as markers for the particular segments. The glomeruli exhibit abundant sialoglycoproteins at the free surface coat of the podocytes as detected by PNA after sialidase representing a major component of the filtration barrier; neoplastic podocytes of glomeruloid bodies in nephroblastomas as well revealed an intense lectin binding despite failing any vascularization. The lectin binding pattern of renal carcinomas varies within a wide range depending on their histological growth pattern. Whereas most renal carcinomas of clear and granular cell type rarely displayed a slight reactivity with lectins at the cell surface and at the luminal aspect of tubulopapillary tumors, a sub-group of carcinomas named chromophobe type exhibited a strong cytoplasmic staining with DBA and PNA after sialidase. Comparative evaluation of normal kidneys revealed an identical binding pattern exclusively in the intercalated cells of the collecting ducts probably indicating a histogenetic origin of these tumors from the collecting duct epithelium. This assumption derives further support from the detection of precursor lesions rarely detected in normal and tumor-bearing kidneys exhibiting the same lectin binding pattern. In accordance with recent observations in the literature the disclosure of a similar lectin binding pattern in renal oncocytomas and their precursor lesions exhibiting oncocytic transformation clearly favors the assumption of an identical histogenetic origin. On the other hand, few cases of a carcinoma mimicking collecting duct epithelium exhibited a broader lectin binding pattern revealing evidence of secretory activity; the histochemical similarities between this unusual carcinoma and transitional cell carcinoma confirmed the suggested origin from the ducts of Bellini. In conclusion, lectin histochemistry may be a useful tool for estimating the characteristics of renal tumors and elucidating their histogenesis.

Epithelium↗
PubMed1989

CA 50 and CA 19-9 antigen expression in normal, hyperplastic, and neoplastic thyroid tissue.

The occurrence of the tumor-associated carbohydrate antigens defined by the monoclonal antibodies (moabs) C 50 and 19-9 has been studied by immunoperoxidase staining of formalin-fixed and paraffin-embedded tissue specimens from normal, hyperplastic, adenomatous, and carcinomatous thyroid tissues. Epithelial expression of these antigens was observed neither in normal nor in hyperplastic thyroid tissue. The antigens were expressed in only 1 of 26 follicular adenomas and the staining in this case was weak and restricted to a few cells. In contrast, the expression of this antigens is marked and progressive in carcinomatous tissues. A high proportion, 48 of 52 papillary carcinomas demonstrated C 50 reactivity, whereas 25 of these tumors expressed the CA 19-9 antigen. Of 25 follicular carcinomas, 15 gave a positive staining for the CA 50 and 6 for the CA 19-9 antigen. CA 50 antigen expression was still detected in tumor cells lacking the CA 19-9 antigen and C 50 reactive material was found in all tissue specimens from medullary carcinomas tested, whereas CA 19-9 antigen staining was consistently negative. This indicates that the moab C 50 which reacts, like the moab 19-9, with the sialylated Lewisa (Lea) blood group determinant also binds to other antigens apart from the sialylated Lea in CA 19-9 antigen negative tumor cells. Although, the functional significance of CA 50 and CA 19-9 antigen expression remains to be investigated, these results suggest that the demonstration of these antigens could provide additional differential diagnostic parameters for the characterization of hyperplastic and neoplastic lesions of the thyroid gland. Further clinical studies will show whether these carbohydrate antigens are useful serum markers for the monitoring of thyroid carcinomas.

Adenocarcinoma↗
PubMed1989

[Ultra-thin, flexible ureteropyeloscopy: a new diagnostic possibility. An animal experiment and clinical pilot study].

Recent advances in fiberoptic technology have resulted in the development of fiberscopes with an outer diameter of less than 6 F and an irrigating or working channel. The feasibility, conditions and benefit of ureteropyeloscopy with ultrathin, flexible endoscopes were evaluated in two sets of investigations: (1) in 6 pigs and (2) in 12 patients during routine retrograde pyelography. Prototypes of flexible endoscopes with a passively deflectable tip, an outer diameter of 5.5 F (1.8 mm) and a 1.5 F (0.5 mm) channel were used. Fine-needle aspiration cytology is possible through the channel under endoscopic control. At present, the lack of maneuverability and the fragility of the fiberscopes limit this method. Its use in the clinical routine, in addition to retrograde ureteropyelography, under local anesthesia is of great promise, however.

Adult↗
PubMed1988

Occurrence and distribution of glycoconjugates in human tissues as detected by the Erythrina cristagalli lectin.

We applied a horseradish peroxidase-Erythrina cristagalli agglutinin (HRP-ECA) conjugate for histochemical staining of tissue sections from various formalin-fixed, paraffin-embedded human tissue specimens. The HRP-ECA conjugate showed broad reactivity, but there was a distinct distribution of native (not masked by sialic acid) and sialic acid-masked ECA binding sites in the various organs. Free ECA binding sites could be detected on red blood cells, lymphocytes of thymus, tonsil, lymph node, and in mucous substances of different organs. Independent of blood group type, the vascular endothelium exhibited strong ECA reactivity. Free ECA binding sites occurred in the cytoplasm of Kupffer's cells in liver, in histiocytic cells of thymus, lymph node, tonsil, and in bone marrow. Podocytes of kidney glomerulus, syncytiotrophoblasts of placenta, megakaryocytes in bone marrow, myelin sheath of nerve, medullary thymocytes, and hepatocytes, as well as islet cells of pancreas, contained only sialic acid-capped ECA binding sites. Inhibiting studies with galactose, lactose, and N-acetyl-lactosamine, as well as other sugars, revealed that this lectin is specific for galactosyl residues. In comparison to galactose and lactose, N-acetyl-lactosamine exhibited the highest inhibitory activity on lectin binding, supporting the concept that this lectin is most reactive with N-acetyl-lactosamine-type (type 2 chain) glycoconjugates.

Blood Vessels↗
PubMed1988

Renal oncocytoma. II. Lectin and immunohistochemical features indicating an origin from the collecting duct.

The present study is aimed to gain more insight into the histochemical properties of renal oncocytomas. Ten oncocytomas and normal kidneys were investigated using several lectins (peanut agglutinin--PNA, Dolichos biflorus agglutinin--DBA and Ulex europaeus agglutinin--UEA) and antibodies against epithelial membrane antigen (EMA), Tamm-Horsfall glycoprotein (THG) and lysozyme. Lectin histochemistry revealed a characteristic binding pattern in renal oncocytomas, with strong DBA-binding and, in some cases, a weaker staining with UEA apparent in the cytoplasm of the oncocytes. PNA binding sites were evident only after enzymatic cleavage of sialic acid by neuraminidase. Comparative evaluation of normal kidneys exhibiting a strict compartmentalization of saccharide moieties in the various nephron segments revealed a similar binding pattern exclusively in interspersed collecting duct epithelium. This striking resemblance suggests that renal oncocytomas may originate from the collecting duct system. Further support for this assumption has been provided by the demonstration of strong cytoplasmic EMA reactivity in the oncocytes. In normal kidneys prominent labeling for EMA was apparent in the very same interspersed cells of the collecting ducts. THG and lysozyme failed to react in renal oncocytomas. In accordance with observations recently reported in the literature, these results clearly favor a histogenetic origin of renal oncocytomas from the collecting duct epithelium.

Adenoma↗
PubMed1988

Renal oncocytoma. I. Cytochrome c oxidase in normal and neoplastic renal tissue as detected by immunohistochemistry--a valuable aid to distinguish oncocytomas from renal cell carcinomas.

Using a polyclonal antibody raised against bovine heart cytochrome c oxidase, the occurrence of this mitochondrial marker enzyme has been investigated in 63 kidney tumors (ten renal oncocytomas, 43 renal cell carcinomas and ten tubulopapillary adenomas) as well as in normal renal tissue by an immunoperoxidase method (PAP-technique). The differentiation between renal oncocytomas and mitochondria-rich carcinomas represents a problem of histopathology since these tumors have a different prognosis and require different patient managements. The strong immunoreactivity in renal oncocytomas contrasted with the much weaker reactivity in renal carcinomas and adenomas. Even mitochondria-rich (granular cell type) carcinomas exhibited only moderate staining intensity. Furthermore, single strongly stained oncocytes or small complexes were sometimes detected in normal renal tissue. The demonstration of marked differences in enzyme content between renal oncocytomas and granular cell carcinomas renders this method suitable for unequivocal distinction between these renal neoplasms. The antibody proved to be a valuable marker for detecting "true" oncocytic transformation in renal tumors and was useful in defining even single oncocytes or small oncocytic lesions.

Adenoma↗
PubMed1987

Renal and cerebral necrosis in survivor after in utero death of co-twin.

A newborn with bilateral renal cortical necrosis and severe cerebral damage in association with a macerated stillborn twin is reported. The alterations in the kidneys and brain of the twin born alive suggest that the primary event took place before birth. Thromboplastic material and embolizing particles derived from the dead fetus may have passed the monoamnionic-monochorionic twin placenta and caused disseminated intravascular coagulation in the living twin, followed by infarction in other organ systems.

Brain Diseases↗
PubMed1985

Immunopathology of AIDS (acquired immune deficiency syndrome) observations in 75 patients with pre-AIDS and AIDS.

Sequential changes in the morphology of immunocompetent and other organs, in the accompanying immunocytological and immunovirological measurements are described in 75 patients with lymphadenopathy syndrome and with AIDS. The data presented demonstrate a stepwise development of the disease from a hyperimmunization syndrome to T-cell immune deficiency. Excessive antigenic stimulation by a large number of infectious organisms or by transfusion of blood and blood products account for antigenic overloading and hyperimmunization. Among such infectious organisms are certain viruses which per se interfere with cells of the immune system as for instance Epstein-Barr virus, cytomegalovirus, and HTLV3. Developing immunological incompetence will favor the persistence of these and other infectious organisms enhancing the damage of the immune reactivity and finally allow lethal infections or malignant tumors to occur.

Acquired Immunodeficiency Syndrome↗
PubMed1982

Histochemical distribution of certain biochemical constituents in the albumin glands of snails.

The presence in situ of the biochemical constituents galactans, proteinase-inhibitors, and erythro-agglutinin anti-A in snail's albumin gland tissues has been demonstrated by histochemical techniques using fluorescein isothiocyanate (FITC)-conjugated counterparts; namely, anti-galactan-specific lectins, different proteinases, and blood group A substance. Invariably, these constituents are localized as globular structures, predominantly within the lobules of the gland tissue. There is a good correlation between the histochemical findings and the previously reported biochemical and serological findings for these substances.

Albumins↗
PubMed1982

[The pathogenetic importance of peanut lectin binding sites in infectious, toxic and neoplastic processes].

Labelled lectins are generally used for identification of mono-, oligo- and polysaccharides in histochemistry. The aim of this work is to demonstrate in addition the importance of the labelled (FITC and peroxidase) lectin from peanut (peanut agglutinin = PNA) with regard to the pathogenesis of some infectious and neoplastic diseases. Thereby, PNA-binding sites have been shown as differentiation marker in embryonic kidneys and in dysontogenetic.

Arachis↗
PubMedDate not supplied

Renal tubular dysgenesis: a report of two cases.

Renal tubular dysgenesis, a congenital disorder of renal tubular development, was diagnosed in two newborns with oligohydramnios and Potter phenotype. Renal tubular dysgenesis (RTD) is a recently recognized congenital disorder of renal tubular development associated with oligohydramnios, Potter phenotype, and neonatal respiratory and renal failure. We report two newborn siblings with typical clinical and anatomic features of RTD. The diagnosis was proven by autopsy in one child. The pediatrician should consider the diagnosis of RTD in a child with congenital anuria and structurally normal kidneys on ultrasound, especially if a maternal history of late trimester oligohydramnios is present.

Anuria↗