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Biomedical subjects

G Seitz

Publications and source records attributed to G Seitz.

At least 109 records · Page 6Linked to original sources
PubMed1990

Glucocorticoid therapy obscures the diagnosis of cerebral lymphoma.

Neuropathological and radiographical findings of two patients with primary CNS B cell lymphoma are presented. Prior to computerized tomographic (CT)-guided stereotactic biopsy both patients had received glucocorticoid therapy which led to marked tumor regression on CT scans and transient improvement of neurological deficits. Despite careful targeting and serial sampling, multiple biopsy specimens examined cytologically, histologically and immunomorphologically showed nonspecific reactive astrogliosis and conspicuous perivascular infiltrates of T lymphocytes. A second biopsy performed after an interval of 2 and 8 weeks, respectively, and short-term discontinuation of dexamethasone therapy in one case, unequivocally established the diagnosis of Non-Hodgkin lymphoma. It is concluded that steroid therapy may obscure the bioptic diagnosis of cerebral lymphoma. In addition to the well-known antiedematous effect of glucocorticoids neuropathologists and neurosurgeons should be aware of a rapid and pronounced lymphodepletive action of steroids on malignant CNS lymphomas.

Astrocytes↗
PubMed1990

Carcinosarcoma of the lung, a tumour which has a poor prognosis and is extremely rarely diagnosed preoperatively.

Out of about 2,000 patients operated on for lung cancer in the period from 1975 to 1990, four were found with the very rare condition carcinosarcoma. The diagnosis was verified by immunohistochemical investigation. The problems concerning this rare tumour are discussed with reference to four case descriptions and with consideration of the pertinent literature. On the one hand, they comprise the difficulty of making a correct histological diagnosis preoperatively, and on the other hand the poor prognosis, even in the NO stage.

Adult↗
PubMed1990

Nephrogenic adenoma of the bladder in a child--immunohistochemical and lectinhistochemical investigations.

A morphological study of a 6-year-old girl with a nephrogenic adenoma of the bladder is presented. The tumor developed 4 years after multiple reconstructive operations of the urinary tract. Immuno- and lectinhistochemically, the tubular structure of the lesion resembled that of a collecting tubule. A conservative approach was the treatment of choice in the absence of microscopically malignant changes.

Adenoma↗
PubMed1989

Characterization of casein kinase II in human colonic carcinomas after heterotransplantation into nude mice.

Casein kinase II (CKII) activity in colorectal tumours was compared before and after heterotransplantation onto nude mice. The test revealed that the enzyme activity was about two-fold enhanced in the tumours isolated from the nude mice when compared to the respective primary tumours from which they were derived. Immunoblots using a polyclonal CKII-specific antibody showed that the increase of activity was due to a higher expression of the enzyme. Immunohistochemical studies on cross sections of nude mouse tumours showed that most of the CKII molecules were located at the peripheral part of the tumour; the central part did not show intense CKII-specific staining.

Animals↗
PubMed1989

Alteration of mitochondrial DNA in human oncocytomas.

Oncocytoma, a benign solid tumor, occurs in a number of organs but most frequently in the kidneys. Its oncocytes display an intensely eosinophilic cytoplasm due to presence of numerous mitochondria. Mitochondrial DNA analysis of six renal cell oncocytomas and adjacent renal tissue was performed using five restriction endonucleases. In the Hinfl restriction pattern, an additional 40 bp band was noted. This new band was demonstrated in all oncocytomas but in none of the corresponding renal tissues or additionally tested renal carcinomas. By reisolating and hybridizing this band to the mitochondrial genome, its sequence was localized within the cytochrome c oxidase subunit I gene. The data suggest that a molecular alteration of mitochondrial DNA is specific for oncocytomas, and this constitutes the first observed mitochondrial DNA change in a human solid tumor.

Adenoma↗
PubMed1989

Increased detectability of somatic changes in the DNA from human tumours after probing with "synthetic" and "genome-derived" hypervariable multilocus probes.

DNA fingerprinting with two minisatellite (33.15, M13) and two simple repeat probes [(GACA)4, (CAC)5/(GTG)s] was performed to screen for somatic changes in the DNA from various solid human tumours in comparison with constitutional DNA from the same patient. Loss of bands or changes in band intensities were observed. Together the probes 33.15 and (CAC)5/(GTG)5 detected deviating fingerprint patterns in 63% of the colorectal carcinomas investigated. In mammary and stomach carcinomas, only 1/11 and 2/11 tumours, respectively, showed differences with either of the three probes, 33.15, (GACA)4 and (CAC)5/(GTG)5.

Breast Neoplasms↗
PubMed1989

[Why are metastases in cirrhotic livers so rare?].

Metastases in livers with cirrhosis are a rare event in comparison to metastases in normal livers. This fact is of great importance for clinical differential diagnosis of tumours of the liver. High metalloproteinase inhibitor contents and especially altered lectins or lectin binding sites in cirrhosis of the liver may help to explain the rare event "metastasis in cirrhosis".

Animals↗
PubMed1989

Multiple cutaneous myxomas coinciding with repeated cardiac myxomas. A syndrome.

We report on a 31-year-old woman who underwent surgery for two metachronous cardiac myxomas - 7 and 9 years after excision of several cutaneous myxomas. Our observation is a further case of a syndrome-like complex of cardiac and cutaneous myxoma(s), pigmentation anomalies and endocrine disorders described only recently. As modern investigative methods and the development of cardiovascular surgery have brought about an essential improvement in diagnostics and prognosis of cardiac myxomas, the knowledge of this syndrome-like complex is of great therapeutic importance. Therefore, in our opinion, echocardiographic investigations are strongly recommended even in asymptomatic patients, once several cutaneous myxomas are diagnosed histologically.

Adult↗
PubMed1989

Decreased cardiac concentration of cGMP kinase in hypertensive animals. An index for cardiac vascularization?

Cyclic GMP (cGMP) kinase is intimately involved in the regulation of vascular smooth muscle tone. Its tissue concentration was determined in normotensive and hypertensive rats by use of monospecific anti-cGMP kinase antibodies. Hearts of spontaneously hypertensive rats and renovascular (Goldblatt II) hypertensive rats contained half the concentration of cGMP kinase than those of the respective normotensive animals. The increase in blood pressure and the resulting left ventricular hypertrophy were correlated inversely with the left ventricular cGMP kinase concentration. This decrease was specific for the left ventricle and was not observed in other tissues. In addition, the cardiac concentration of cGMP kinase was unchanged in hyperthyroid animals that had comparable left ventricular hypertrophy and mild hypertension. This suggested that in severe renovascular hypertension the decrease in cardiac cGMP kinase concentration is caused by a relative lack of cardiac vessel growth during the development of hypertrophy. In agreement with this conclusion, immunohistochemistry of cardiac cross sections showed that cGMP kinase was exclusively located in cardiac vessels. In support of this localization, the maximal arterial blood flow of heart, liver, skeletal muscle, and kidney correlated excellently with the cGMP kinase content of the respective organ. These results suggest that the cGMP kinase concentration of nonsmooth muscle tissues depends on the amount of organ-specific vascular smooth muscle and may be used as an index for the vascularization of these organs.

Animals↗
PubMed1989

[Tumor-specific changes in the mitochondrial genome of oncocytomas].

Two astrocytomas, 5 colon carcinomas, 3 clear cell carcinomas of kidney, 5 renal oncocytomas and 1 oxyphile adenoma of thyroid were examined for mitochondrial DNA-alterations applying 5 different restriction enzymes (Alu I, Hae III, Hpa II, Rsa I, Hinf I). Only by applying Hinf I restriction enzyme digestion we were able to prove alterations of the mitochondrial DNA in oncocytomas (2 additional bands of about 55 or 35 base pairs). This was the first proof of mitochondrial DNA-alteration in a human tumor. The present sequence analyses of DNA-alteration will help to explain which importance is attached to the alterations regarding genesis of oncocytic tumors.

Adenoma↗
PubMed1988

[Cushing syndrome--a leading symptom in bronchial carcinoid].

Bilateral adrenalectomy was performed in a 27-year-old male because of Cushing's syndrome. After 7 years a peripheral bronchial carcinoid was diagnosed; ACTH values went back to normal only after removal of the carcinoid. In the literature, there are 31 case reports on bronchial carcinoids associated with Cushing's syndrome. The Cushing's syndrome precedes the diagnosis of a tumor for months to years in at least half of the cases. Most of these patients first underwent adrenalectomy and/or hypophysectomy for their primarily endocrine symptoms and signs.

ACTH Syndrome, Ectopic↗
PubMed1988

Investigations of the estrogen (ER-ICA-test) and the progesterone receptor in the prostate and prostatic carcinoma on immunohistochemical basis.

Estrogen (ER) and Progesterone receptors (PR) were demonstrated immunohistochemically on frozen sections from 11 prostatectomy and 7 cystoprostatectomy specimens in the nuclei of various cell types. The periglandular fibrocytes and smooth muscle cells were extensively positive, the interglandular stromal cells were only partly so. Normal basal cells stained focally positive, hyperplastic basal cells stained extensively. The glandular secretory epithelium and atrophic glands were negative. The same findings were obtained in hyperplastic nodules. Both ER and PR also occurred in the urothelium of central prostatic ducts and of the prostatic urethra. The fibrous stroma around the ejaculatory ducts and seminal vesicles was extensively positive while the epithelium was negative. The smooth musculature of the seminal vesicles was only partly positive. On large field sections, the ER as well as the PR were numerically equally distributed throughout the inner zone of the prostate and the prostate proper. 12 prostatic carcinomas (G I-G III) were ER- and PR-negative. Estrogens may contribute to nodular hyperplasia by triggering a stromal proliferation with a secondary inductive epithelial growth. Obviously they do not act directly on prostatic carcinoma but inhibit growth via the hypophyseal-testicular axis. The biological significance of the PR in the prostate is unknown.

Humans↗
PubMed1988

Histology and immunohistochemistry studies in prostate cancer.

Histopathologic diagnosis of prostate carcinoma is not yet free of problems. There are particular difficulties in demarcating atypical forms of hyperplasia from well-differentiated carcinomas and in diagnosing and classifying incidental carcinomas. With the aid of conventional histology, however, nearly all diagnostic problems relevant for the patient can be solved. In routine diagnostics, modern immunohistochemical techniques are particularly helpful in assessing metastases of an undetected primary tumor. New immunohistochemical techniques provide insight into the receptor content of the prostate and show the histogenesis of prostate carcinoma in a new light. The estrogen receptor (modified ER-ICA test) is present in the nuclei of stromal cells and of basal cells within the glands, but not in the secretory epithelium. The receptor-associated protein--ER-D5--is found in the cytoplasm of stromal and basal cells. In basal cells and secretory epithelium, keratins show a different pattern. Immunohistochemically common adenocarcinomas display the pattern of secretory epithelium; urothelial and squamous cell carcinomas, on the contrary, display the pattern of basal cells. This finding does not support the opinion that the basal cell is the stem cell of secretory epithelium and the precursor cell of prostate carcinoma.

Carcinoma↗
PubMed1988

Hepatic reperfusion injury following orthotopic liver transplantation in the rat.

At 24 hr following orthotopic transplantation, rat liver grafts were perfused in situ for 7 min with trypan blue, a vital dye that provides information on hepatic microcirculation and stains nuclei of nonviable cells. Spotty and uneven dye distribution was observed indicating that hepatic microcirculation was disturbed 24 hr following transplantation surgery. Under these conditions, 15-20% of the hepatocytes were nonviable as assessed from trypan blue staining and frank necrosis. In contrast, perfusion of livers from untransplanted rats or liver explants exposed to cold ischemia for 60 min were judged normal by the criteria of uniform distribution of dye in the organ and absence of necrosis and nuclear dye uptake. Thus the observed damage was associated with reintroduction of blood and can therefore be classified as a reperfusion injury. The altered microcirculation and cell death following the operation was reduced markedly by perfusion of the cold, ischemic explant with nitrogen-saturated but not with oxygen-saturated buffer for 5 min prior to the implantation operation. Protection was even greater if the perfusion medium contained verapamil (20 micrograms/ml), a Ca++ channel blocker. We conclude that reperfusion of the stored liver causes an oxygen-dependent alteration in hepatic microcirculation that leads to hypoxia and scattered hepatocellular necrosis in the implanted graft. Brief perfusion of the hypoxic implant under anaerobic conditions may remove substrates involved in oxygen radical generation and prevent reperfusion injury upon introduction of oxygen into the graft via the blood. Taken together, these results suggest that removal of Euro-Collins' solution under anaerobic conditions may be beneficial clinically in preventing injury of surgical explants.

Animals↗
PubMed1987

Prolongation of graft survival in allogeneic islet transplantation by (-) 15-deoxyspergualin in the rat.

The effect of 15-Deoxyspergualin, a novel drug which has been described to have anti-tumour activity, on allogeneic graft survival (Dark Agouti----Lewis rats) after pancreatic islet transplantation was tested. A marked prolongation of graft survival could be shown using doses of 1.0, 2.5 and 5.0 mg Deoxyspergualin/kg on day 0 until day +9 post transplantation. A maximum of 55.6 days (average) survival time was observed using 2.5 mg/kg Deoxyspergualin compared to 5.2 +/- 0.6 days without immunosuppression. Using the chemiluminescence reaction of recipient monocytes after islet transplantation, a marked suppression of the monocyte system exceeding the treatment period could be observed. Since, in contrast to cyclosporin, B-cell toxicity could not be shown, the new drug seems to be a hopeful step towards successful allogeneic islet transplantation for treatment of diabetes.

Animals↗
PubMed1987

Immunohistochemical estrogen receptor demonstration in the prostate and prostate cancer.

Immunohistochemical investigations of human prostate and human prostate cancer were performed using two different monoclonal antibodies for the demonstration of estrogen receptors (ER). One marked the nuclear estrogen receptor protein (ERICAR, Abbott Laboratories), whereas the other one marked an estrogen receptor-associated cytoplasmic protein (ER-D5 kit, Amersham Buchler). 12 transurethral resection specimens with benign prostatic hyperplasia and 10 prostatic carcinomas were investigated by ERICA. Only in 1 specimen was a focally ERICA-positive basal cell hyperplasia found. The ER-D5 kit yielded a constantly positive reaction of stromal cells, especially smooth muscle cells. Basal cell hyperplasia and squamous metaplasia, alterations which can occur during estrogen application, were always strongly ER-D5-positive. Eleven (13.4%) out of 82 prostate carcinomas were focally positive. The staining results with ER-D5 are in good accordance with biochemical estrogen receptor investigations which demonstrated the estrogen receptors especially in the fibromuscular stroma. Furthermore, the results show that therapeutically applied estrogens do not directly inhibit the growth of prostatic carcinoma, however, the effect is an indirect one by suppressing androgen synthesis of the testis. The different staining results with ER-D5 and ERICA can be explained by the low ER concentration of prostate, the concentration is evidently below the limits of detectability with ERICA.

Antibodies, Monoclonal↗
PubMed1987

Neoplasm to neoplasm metastasis. Pheochromocytoma harboring a metastasis of breast cancer.

Breast cancer commonly metastasizes to the adrenal glands. Metastases to an already existing adrenal gland tumor, however, are a rare finding. To our knowledge, this report represents the first case of a breast carcinoma metastasizing to a pheochromocytoma. Metastases of a cancer to another coexisting tumor in the same individual is an unusual event.

Adrenal Gland Neoplasms↗