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L Weissbach

Publications and source records attributed to L Weissbach.

At least 109 records · Page 6Linked to original sources
PubMed1987

Localization of solitary and multiple metastases in stage II nonseminomatous testis tumor as basis for a modified staging lymph node dissection in stage I.

Because of a continuing need for pathological staging of clinical stage I testicular tumors an investigation was performed to determine the primary sites of metastatic involvement of the retroperitoneal lymph nodes and to define narrowly limited ipsilateral areas of lymph node dissection strictly for the purpose of staging. Surgical/pathological localization of solitary metastases provides the most direct evidence of primary lymphatic spread. There were 214 consecutive patients with stage II disease (excluding bulky disease) evaluated with respect to localization relative to the side of the involved testis and the number of metastases up to 5 cm. Solitary metastases of 5 cm. or less were found in 74 patients, 53 patients had 5 or less lymph nodes of 2 cm. or less and 87 patients had more than 5 lymph nodes of between 2 and 5 cm. Solitary nodes of the right testis tumor were located with decreasing frequency in the upper and lower interaortocaval, lower paracaval and precaval, upper precaval and right common iliac, upper paracaval and upper preaortic zones. Primary deposits of the left testis tumor were seen predominantly in the upper para-aortic zone. Upper preaortic and lower para-aortic zones were involved infrequently, and other areas were affected only in rare cases. These data contradict the assumption of a testicular lymph center located at the openings of the testicular veins into the vena cava and left renal vein, respectively. Multiple metastases were spread over the entire retroperitoneum, except for the external iliac regions. Hilar/suprahilar metastases were seen infrequently. Ipsilateral areas are defined according to primary involvement. A modified retroperitoneal lymph node dissection within ipsilateral areas is proposed as a staging operation for clinical stage I disease and a radical retroperitoneal lymph node dissection is indicated for pathological stage II disease.

Humans↗
PubMed1987

Simian virus 40 (SV40) DNA replication: SV40 large T antigen unwinds DNA containing the SV40 origin of replication.

The simian virus 40 (SV40) large T antigen (large tumor antigen), in conjunction with a topoisomerase, a DNA binding protein, and ATP, catalyzed the conversion of a circular duplex DNA molecule containing the SV40 origin of replication to a form with unusual electrophoretic mobility that we have named form U. Analysis of this molecule revealed it to be a highly underwound covalently closed circle. DNA unwinding was not detected with DNA containing a SV40 T-antigen binding site II mutation that renders the DNA inactive in replication. The unwinding reaction requires the action of a helicase, and SV40 T-antigen preparations contain such an activity. The T-antigen-associated ability to unwind DNA copurified with other activities intrinsic to T antigen [ability to support replication of SV40 DNA containing the SV40 origin, poly(dT)-stimulated ATPase activity, and DNA helicase]. However, in contrast to the unwinding activity, the SV40 T-antigen-associated helicase activity was not sequence-specific. A variety of labeled oligonucleotides hybridized with circular single-stranded DNA were displaced by T antigen in the presence of ATP.

Adenosine Triphosphatases↗
PubMed1987

Replication of simian virus 40 origin-containing DNA in vitro with purified proteins.

Simian virus 40 (SV40) DNA replication dependent on the SV40 origin of replication and the SV40 large tumor (T) antigen has been reconstituted in vitro with purified protein components isolated from HeLa cells. In addition to SV40 T antigen, these components included the DNA polymerase alpha-primase complex, topoisomerase I, and a fraction that contained a single-stranded DNA binding protein. The latter protein, which sediments at 5.1 S on glycerol gradients and copurifies with two major protein species of 72 and 76 kDa, was isolated solely by its ability to support SV40 DNA replication. The purified system retained the species-specific DNA polymerase alpha-primase requirement previously observed with crude fractions; the complex from HeLa cells supported SV40 replication, whereas that from calf thymus and mouse cells did not. DNA containing the polyomavirus origin of replication was replicated in a system containing polyomavirus T antigen, the HeLa single-stranded DNA binding protein-containing fraction, and DNA polymerase alpha-primase complex from mouse, but not HeLa, cells. While crude fractions yielded closed circular duplex DNA, none was detected with the purified system. Nevertheless, the addition of a crude fraction to the purified system yielded closed circular monomer products.

Antigens, Polyomavirus Transforming↗
PubMed1987

Adjuvant chemotherapy in nonseminomatous testicular tumour stage II.

Preliminary results of a random prospective trial to investigate the necessary extent of adjuvant chemotherapy are presented. Two hundred and sixty-three patients entered the study, of whom 210 (forty-eight stage IIA patients, 162 stage IIB patients) could be evaluated. Two hundred and eight patients are currently free of disease, since three of the five patients with relapses (one stage IIA patient, four stage IIB patients) achieved a complete remission. One IIB patient who had relapsed achieved a partial remission, whereas the final IIB patient who progressed is presently undergoing chemotherapy. One patient died of pneumonia after the first course of VBP. Toxicity consisted mainly of nausea, vomiting and loss of hair, 17% of the patients suffered infection, and 7% experienced sepsis.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

Clinical and endocrinological characterization of two subjects with Reifenstein syndrome associated with qualitative abnormalities of the androgen receptor.

The androgen receptor in fibroblasts cultured from a biopsy of scrotal skin from 1 subject with Reifenstein syndrome has been found to be normal in amount and to bind dihydrotestosterone with normal affinity but to be qualitatively abnormal as evident by thermolability and instability upon ultracentrifugation. The family study of this subject and endocrine studies document androgen resistance in the index patient and his affected uncle. These findings provide evidence for X-linkage of this disorder, and suggest that the mutations that give rise to this phenotype are probably allelic to the mutations of the androgen receptor that cause testicular feminization.

Adolescent↗
PubMed1987

Diagnosis of urothelial tumor by ureterorenoscopy.

In the past, radiologically detected filling defects in the upper urinary tract were correctly interpretable only by means of cytological techniques. The introduction of ureterorenoscopy has provided a reliable method for the detection of tumors in the ureter and renal pelvis. In contrast to transurethral ureterolithotripsy, diagnostic ureterorenoscopy entails few complications. It thus fills a diagnostic gap and facilitates therapeutic planning. A report is presented on 15 patients with obscure hematuria, or unclear filling defects in the upper urinary tract. In 10 patients, the unequivocal diagnosis of urothelial carcinoma was endoscopically and bioptically established by ureterorenoscopy. Small nonradiopaque concrements were found in 3 cases. The origin of hemorrhage could not be determined in 2 patients.

Adult↗
PubMed1987

[Dressing technic with silastic foam following penis operations].

Silastic foam has very good properties as dressing material. After operations on the penile urethra or the corpora cavernosa the liquid foam is applied to the wound area. The foaming material avoids formation of pouches and hollow spaces. The compressive bandage prevents post surgical edemas and hematomas respectively. It can be removed without pain.

Humans↗
PubMed1987

[The T category and metastasis in testicular tumors].

On the background of the advantageous prognosis of patients with testicular tumors we define subgroups in which therapy can be reduced. Basing on the distribution of metastases, especially the localisation of solitary nodes, staging LA may be limited to certain regions in patients with non-seminomas. The modification of irradiation fields for seminomas is difficult as the predictive value of negative diagnoses (CT, sonography, lymphography) is only 77%. As the topography of metastases does not differ within the various T-categories, the necessary extent of irradiation cannot be related upon them. In clinical stage I contralateral iliacal fields have not to be included. In left-sided tumors no positive solitary nodes were found in the ipsilateral iliac region, subsequently we suppose that this area might be preserved. In right-sided tumors occasional solitary nodes in the ipsilateral field are not necessarily due to an infiltration of the epididymis; therefore we recommend in general a prophylactic irradiation of the ipsilateral iliac region. An inguinal irradiation should be reserved only for pre-operated patients and an involvement of the scrotal wall.

Humans↗
PubMed1986

Simian virus 40 DNA replication in vitro: study of events preceding elongation of chains.

We have evidence for the formation of a stable preelongation complex during the replication of simian virus 40 (SV40) origin containing DNA (ori+ DNA) in vitro. Preincubation of ori+ DNA with HeLa cytosolic extracts and SV40-encoded large tumor antigen (T antigen) in the absence of deoxynucleoside triphosphates eliminates a lag that normally precedes replication. This effect requires ATP and is inhibited by RNase A; subsequent elongation is inhibited by aphidicolin but not by RNase A. A T antigen and SV40 origin-dependent complex can be isolated by gel-filtration chromatography of preincubation reaction mixtures. In both cases, the products formed by replication after complex formation resemble those formed during in vitro replication reactions described previously. HeLa cytosolic extract was separated into two ammonium sulfate fractions: a 0-40% fraction (AS 40) that shows low levels of DNA synthesis and a 40-65% fraction (AS 65) that is inactive by itself but stimulates synthesis when added to the AS 40 fraction. DNA synthesis by these combined fractions has the same requirements as crude extract, occurs in two stages as described above, and is sensitive to RNase A. Pretreatment of both fractions with micrococcal nuclease eliminated replication activity, whereas the combination of a pretreated fraction (either AS 40 or 65) with an untreated fraction was active. A heat-inactivated (55 degrees C, 5 min) AS 65 fraction restored replication activity to the combination of micrococcal nuclease-treated AS 40 and AS 65 fractions.

Ammonium Sulfate↗
PubMed1986

Role of DNA polymerase alpha and DNA primase in simian virus 40 DNA replication in vitro.

The role of DNA polymerase alpha (pol alpha) and DNA primase has been investigated in the simian virus 40 (SV40) DNA replication system in vitro. Removal of pol alpha and primase activities from crude extracts of HeLa cells or monkey cells by use of an anti-pol alpha immunoaffinity column resulted in the loss of replication activity. The addition of purified pol alpha-primase complex isolated from HeLa cells or monkey cells restored the replication activity of depleted extracts. In contrast, the pol alpha-primase complex isolated from either mouse cells or calf thumus did not. Extracts prepared from mouse cells (a source that does not support replication of SV40) did not replicate SV40 DNA. However, the addition of purified pol alpha-primase complex isolated from HeLa cells activated mouse cell extracts. pol alpha and primase from HeLa cells were extensively purified and separated by a one-step immunoaffinity adsorption and elution procedure. Both activities were required to restore DNA synthesis; the addition of pol alpha or primase alone supported replication poorly. Crude extracts of HeLa cells that were active in SV40 replication catalyzed the synthesis of full-length linear double-stranded (RFIII) DNA in reaction mixtures containing poly(dT)-tailed pBR322 RFIII. Maximal activity was dependent on the addition of oligo(dA), ATP, and creatine phosphate and was totally inhibited by aphidicolin. Since pol alpha alone could not replicate this substrate and since there was no degradation of input DNA, we propose that other enzymatic activities associate with pol alpha, displace the non-template strand, and allow the enzyme to replicate through duplex regions.

Animals↗
PubMed1986

Familial tumor of the testis.

A survey of the literature since 1928 yields reports on 100 patients with testicular tumor occurring in families. From our own case material we present clinical data on 11 additional patients. Non-twin brothers are most often involved. Presently available data are too limited to assess the impact of a possible genetic disposition on the development of malignoma of the testis. Additional case reports and register studies are needed. Equally undecided is the question if sperm banking of testicular tumor patients prior to therapy carries any genetic risk to the progeny.

Adult↗
PubMed1986

Aneurysmal hemorrhage of the kidney caused by angioleiomyoma.

A small angioleiomyoma consisting of proliferating smooth muscle cells and vessels caused macrohematuria in a 52-year-old female patient. The locally ill-defined tumor in the fatty tissue of the renal pelvis immured small arteries and veins as well as an interlobar artery, and caused damage to the vascular walls accompanied by the development of aneurysm, perforation and fistulation into the renal pelvis, by mechanisms open to various pathogenetic interpretations. Preoperative radiological diagnosis yielded a subcapsular hematoma, and showed more intense contrast medium staining of the upper renal pole. Dysontogenetic tumors are most frequently located in the renal cortex and are capable of locally destructive growth. They are usually well defined and of nodular structure. As, in our case, an exact diagnostic assessment of the process was lacking and both the location and growth pattern of the tumor were atypical, an organ-preserving resection was deemed unsuitable and nephrectomy was performed.

Aneurysm↗
PubMed1986

[Transurethral ureterolithotripsy in the treatment of ureteral calculi].

We report our experiences with transurethral ureterolithotripsy for treatment of ureteral calculi in 68 patients. 67% of the ureteral stones were extracted successfully. Failures and complications occur often by higher localisation of concrements. Only in 2 patients major complications occurred. Late complications (Ureter Manipulation Syndrome-UMS) were not observed in our patients. In cases with ureteral perforations or mucous membrane lesions ureteral stent must be used.

Adult↗
PubMed1985

Sperm parameters and ejaculation before and after operative treatment of patients with germ-cell testicular cancer.

In testicular tumor patients, the stage of disease is most accurately determined by retroperitoneal lymph node dissection (RLND) and histologic examination of the operative specimen. The resection of possibly metastatic nodes is essential for securing a good prognosis. However, the most frequently encountered loss of ejaculatory function is a major disadvantage of radical RLND. In patients who intraoperatively proved to be free of metastases, we successfully employed a modified technique aiming at the preservation of sympathetic nerve fibers which mediate ejaculation. In 29 of 37 patients (78%), postoperative ejaculation was antegrade. It was retrograde in 5 of 37 patients (13.5%); 3 patients had no emission. These results are retrospectively compared with results of radical RLND in 87 patients of whom 64% suffered a total loss of ejaculation and only 23% had antegrade ejaculation. RLND did not affect sperm count, motility, and cell morphology. Potentia coeundi was preserved in all cases, although 27% of patients experienced diminished erectility or libido.

Adolescent↗
PubMed1985

In vitro replication of duplex circular DNA containing the simian virus 40 DNA origin site.

Extracts (0.2 M NaCl) of HeLa cells support replication of DNA containing simian virus 40 (SV40) origin in the presence of SV40 large tumor (T) antigen. The reaction leads to the accumulation of high molecular weight products that represent DNA containing one parental strand and one progeny strand as well as duplex molecules that contain both strands derived from the input deoxynucleoside triphosphates. The replication reaction is inhibited by aphidicolin and by camptothecin, two inhibitors known to inhibit eukaryotic DNA replication in vivo.

Antigens, Viral, Tumor↗
PubMed1985

Steroid receptor status of human testicular tumors.

Biopsies of 9 testicular tumors were examined for the presence of cytoplasmic receptor proteins for estrogens, progestins, androgens, and glucocorticoids. Using an arbitrary threshold value of 10 fmol/mg cytosol protein for a postive assay, only 1 of 9 tumors was estrogen-receptor positive. However, no receptor-specific 8S binding could be detected by low salt sucrose gradient centrifugation. 1 tumor was progesterone-receptor positive. No androgen receptors could be demonstrated. In contrast, 8 of 9 neoplasms contained significant quantities of glucocorticoid receptors exclusively sedimenting at 8S. Our findings suggest that androgens, estrogens, and progestins are unlikely to play a major role in the natural history of testicular tumors. The presence of glucocorticoid receptors might offer a chance for endocrine manipulation of the development and growth of these neoplasms by glucocorticoids.

Adolescent↗
PubMed1985

Localization, incidence, diagnosis and treatment of extratesticular germ cell tumors.

On the basis of a literature search yielding 243 case histories, the rare extratesticular germ cell tumor is surveyed with respect to incidence, primary localization, histology and treatment. In this context, we report on 6 patients with negative results on clinical examination of the testes (palpation, scrotal ultrasonography). We briefly discuss a suitable method of diagnosing occult and burnt-out tumors. Polychemotherapy (vinblastine, bleomycin, cis-platinum) has been found to be very effective. The resulting high rates of remission thus lead to an improvement of overall prognosis.

Adolescent↗