PubMed Health⌕ Search

Biomedical subjects

W Göhde

Publications and source records attributed to W Göhde.

At least 37 records · Page 2Linked to original sources
PubMed1997

Increased number of cancer cells in bronchial washing fluid detected by combining conventional cytology and high-resolution flow cytometry.

The present study was performed to improve early lung cancer diagnosis in bronchial washing fluid, thereby increasing the diagnostic sensitivity of bronchoscopy by means of high-resolution flow cytometry (FC). We combined dual-parameter DNA/protein FC and conventional cytology in bronchial washing fluid samples from 112 patients with neoplastic and non-neoplastic lung diseases and found 43% of histologically confirmed tumor cases to be cytologically positive; 63% of the tumor samples were aneuploid, 52% of the aneuploid cases were cytologically positive and 48% were negative. In the negative cases, FC was an independent diagnostic factor. In 32% of the cases, FC also failed to detect abnormalities. However, the combination of both techniques increased the sensitivity in detecting neoplastic cells to 73%. Furthermore, simultaneous DNA/protein analysis allowed the recognition of aneuploid cell lines not detectable by single DNA measurement. Identification of aneuploid subpopulations by dual-parameter analysis in cytologically negative one-parameter FC "diploid" samples assumes an important diagnostic value. Dual-parameter DNA/protein FC is a valuable technique that increases the diagnostic yield of bronchoscopy with no risk for the patient and a low additional cost.

Aneuploidy↗
PubMed1995

Sex determination in dioecious plants Melandrium album and M. rubrum using high-resolution flow cytometry.

High-resolution flow cytometry was used to analyze nuclear DNA content in dioecious plants Melandrium album and M. rubrum. Very low coefficients of variation (0.53-0.70%) of G0/1 peaks were obtained after the analysis of nuclei isolated by chopping leaf tissues. In both species, females have lower DNA content than males due to sex chromosome heteromorphism. This made it possible to discriminate peaks belonging to female and male nuclei on the same histogram and permitted unambiguous sex identification in both species. The results indicated the possibility of diagnosing sex also in other heterogametic dioecious plants. The assay described here might be interesting in any area where rapid sex identification is required at an early stage of plant development.

DNA, Plant↗
PubMed1994

The relevance of flow-cytometric DNA content in the evaluation of lung cancer.

Cells from a group of 185 patients suffering from malignant tumours (160 non-small-cell lung carcinoma, 13 small-cell lung carcinoma, and 12 non-epithelial tumours) and 6 with benign lung tumours were studied by flow cytometry in order to detect the prognostic value of DNA content. A total of 144 (90%) non-small-cell lung carcinomas (NSCLC) and 8 (62%) small-cell lung carcinomas (SCLC) exhibited aneuploidy. Furthermore 52% (83 patients) NSCLC, 24% (3 patients) SCLC and 50% (6 patients) non-epithelial tumours demonstrated multiclonality. Benign cases showed diploid DNA content. For actuarial survival analysis using the Bergesson and Gage method and the Greenwood variance, 142 patients were selected. Statistical comparisons were made by the use of the t-test for unpaired data between fixed times. No correlation was observed between ploidy and stage, histological grading or treatment modality. A statistically significantly better survival was observed after 12, 18 and 24 months of follow-up for diploid and monoclonal (with the exclusion of hypo- and hypertetraploid) patients. Thus, flow-cytometric DNA analysis may be useful in prognostic assessment of human lung tumours.

Adult↗
PubMed1992

Cellular heterogeneity of DNA/total-protein content in human lung tumors, as determined by flow cytometry.

With the aim of distinguishing neoplastic cell sub-populations of different prognostic and diagnostic significance, dual-parameter measurements (DNA/protein) have been simultaneously determined in a (256, 256) channel matrix in lung samples derived from 110 patients affected by neoplastic and non-neoplastic lung diseases. Biparametric analysis demonstrated that cells with abnormally high red fluorescence (i.e., protein content), which is indicative of unbalanced growth, were often observed in malignant tumors as compared with normal lung samples. Furthermore, the dual-parameter analysis allowed recognition of additional aneuploid tumor-cell lines, indicating that the frequency of cytometrically determined diploid tumor is lower than that previously described by DNA monoparametric analysis. The recognition of aneuploid subpopulations by dual-parameter analysis in clinically and histologically negative one-parameter flow-cytometric "diploid" samples assumes important diagnostic value. The results have also shown the presence of multiple protein sub-populations in clones with the same ploidy value, indicating a higher level of cellular heterogeneity than demonstrated by DNA monoparametric measurements.

Adenocarcinoma↗
PubMed1991

Flow sorting of tumor cells for morphometric analysis, particularly of rare cells.

Using flow cytometric DNA measurement and sorting combined with morphometric light microscopy, different groups of cells were studied in a human melanoma pleural effusion, a human melanoma lymph node metastasis and a mouse tumor, as well as in normal reference tissues. Beside cells of the predominant tumor cell population, three types of rare tumor cells were studied after enrichment by sorting: a) giant cells from the greater than 8c region, comprising about 5% of the tumor cells, b) binucleated and multinucleated cells with unequal nuclear sizes within the same cell, found at frequencies of about 1.5%, and c) less than 2c cells which were derived from the so-called "debris"-region of the DNA histogram, found at frequencies of about 1 to 6%. All these rare cells were found only in the malignant tumors and not in the benign reference tissues. Morphometry showed that the increase in the cellular DNA content in the different fractions of tumor cells was combined with an increase in the cellular and nuclear sizes. However, the n/c-ratio was constant in the whole range of tumor cell fractions, including the fractions from the the less than 2c and the greater than 8c regions. The n/c-ratio of the less than 2c cells and giant cells differed from that of corresponding normal cells underlining their origin from the predominant tumor cell population. The possible linkage between the occurrence of the three rare cell types and genetic instability of tumors related to faulty nucleus and cell division is discussed.

Animals↗
PubMed1991

In vitro staining of islets of Langerhans for fluorescence-activated cell sorting.

A previously described technique from the author's laboratories for purification of pancreatic islets by fluorescence-activated cell sorting used the dye neutral red (NR) to obtain specific fluorescence of islets sufficient to give a sorting signal. A major drawback with this technique was the need to inject the dye intravascularly before excision of the pancreas. Preliminary investigations showed that NR would produce selective staining of islets by topical application in vitro but only at low concentrations that were insufficient to give fluorescence strong enough for sorting. The chelating agent dithizone (DTZ) produces bright red staining of islets by topical application in vitro. Further studies showed that dithizone-stained islets exhibited moderately strong fluorescence that faded too quickly for reliable sorting. By combining both NR and DTZ staining in vitro, selective fluorescence of islets was obtained that was sufficient to allow efficient sorting. Using the combined DTZ/NR stain the yield of islets obtained by sorting from a single rat pancreas was 569 +/- 72 (n = 16), corresponding to 83% of the islets present in the digest. The mean purity of the preparation, confirmed by histologic examination, was 80%. The viability of the islets was shown to be good both by supravital staining and by the successful correction of streptozotocin diabetes in syngeneic rats following transplantation of sorted islets.

Animals↗
PubMed1990

A specific fluorescent dye for ex situ staining of vital islets of Langerhans: neutral red.

We present a new technique for specific ex situ fluorescent staining of islets of Langerhans with neutral red. Depending on the concentration of neutral red (1 microgram/ml), this technique allows the differentiation between exocrine and endocrine pancreatic tissue, according to differences in fluorescence intensity. Pancreatic islets can be stained not only in situ, but in particular ex situ after pancreas digestion. Since intravital staining of the pancreas in situ with neutral red is not applicable in human transplantation, the staining procedure ex situ may be a useful tool for islet purification by particle sorting, using a fluorescent-light-activated system; thus, a sufficient mass of purified islets for free transplantation may be isolated.

Animals↗
PubMed1989

Radiation-induced diploid spermatids in mice.

Diploid elongated spermatids of mice were enriched by flow cytometry and cell sorting using a new type of sorter (Partec). The sorted abnormal spermatids were identified morphologically and by nuclear area integration. The radiation-induced increase in the frequency of diploid elongated spermatids was monitored with time following acute X-ray exposure of mice. Dose-response curves for acute 60Co-gamma and 14 MeV neutron irradiations yielded an RBE value of 4.3 for the doubling of the control level.

Animals↗
PubMed1989

Separation of pancreatic islets by fluorescence-activated sorting.

To allow clinical pancreatic islet transplantation, the yield and purity of islets must be improved. Intravital staining of islets with neutral red is a specific, nontoxic technique for labeling islets of various species. Using neutral red-stained rat islets, we investigated the known fluorescence absorbance and emission spectra in comparison with unstained exocrine tissue and have shown that stimulation with light of wavelength between 500 and 560 nm produces detectable emission greater than 610 nm, which is absent from unstained exocrine tissue. The PARTEC cell sorter is an inexpensive alternative to currently available fluorescence-activated cell sorters and has a sorting mechanism based on a piezoelectric valve. We made extensive modifications to this machine to allow passage of particles up to 300 micron diam. Using rat pancreas stained intravitally with neutral red and dispersed by intraductal collagenase technique, we have shown that islets can be accurately identified in a high-speed flow system and sorted to a purity of greater than 90% islet tissue. The islets remain intact and viable as determined by supravital staining and isogeneic transplantation to the kidney capsule site. These studies prove the feasibility of separating intact islets by fluorescence-activated sorting.

Animals↗
PubMed1989

[Results of impulse cytophotometry in malignant tumors of the head and neck. A prognostic parameter?].

Tumour biopsies of 93 patients with head and neck malignancy were analysed by cytophotometry. Ploidy and the proportion of cells in S-phase were measured. Tumours were classified as proliferative if the S-phase fraction was greater than 8%; the rest were classified as being less proliferative. Proliferative tumours produce local and distant metastases earlier and more frequently, so that the proportion of cells in S-phase is of prognostic importance. The response to chemotherapy of irradiation was no different in either group.

Carcinoma, Squamous Cell↗
PubMed1988

The applications of the BrdUrd-technique for the estimation of cycling S-phase cells in human renal cell carcinoma.

After testing the BrdUrd technique on experimental tumour cell lines, we applied the technique to human renal cell carcinoma in vitro. We compared the results with the data acquired after FCM analysis and 3H-thymidine treatment. In contrast to BrdUrd the 3H-thymidine uptake seemed to be limited in suspended cells. FCM data represented the DNA distribution of cells. BrdUrd labelling on the other hand detected DNA synthesizing cells. Only both methods in parallel were able to discriminate between proliferating cells and resting cells with an S-phase equivalent DNA content.

Bromodeoxyuridine↗
PubMed1987

A new anthracycline regimen for prolymphocytic leukemia? Study of a case report with flow cytometric implications.

A case of prolymphocytic leukemia (PL) is reported, which showed a good response to a new antiblastic schedule (4-epidoxorubicin-asparaginase-dexamethasone) in spite of the resistance to other chemotherapy regimens. However during the course of the disease it was possible to observe the terminal appearance of a small aneuploid cell population in the peripheral blood of the patient and, in the same time, the clinical condition deteriorated considerably. The significance of this neoplastic progression and the pros and cons of aggressive chemotherapy regimens remain to be carefully evaluated in PL and related disorders.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1986

DNA aneuploidies in adult patients with acute myeloid leukemia. Incidence and relation to patient characteristics and morphologic subtypes.

Analyses of the cellular DNA content were carried out by flow cytometry (FCM) in 148 adult patients with acute myeloid leukemia (AML) to assess the incidence of DNA aneuploidies and its relation to patient characteristics and morphologic subtypes. DNA aneuploidies were found in 54 of 131 patients with de novo AML (41.2%) and in 4 of 17 patients with AML after preleukemic syndromes. Subclassification according to morphology revealed the lowest rate of DNA aneuploidies in M1 leukemias (25%) and a significantly lower degree of DNA aneuploidy in M1 and M2 cases as compared to M4 and M5 subtypes (P less than 0.05). Within the group of M4 and M5 leukemias, patients less than or equal to 40 years of age had a higher frequency of aneuploid DNA stemlines (71.4%) than older patients (33.3%) (P less than 0.025). No differences between patients with and without DNA aneuploidy were identified for the initial leukocyte count, serum LDH, bone marrow S-phase index, bone marrow cell count/mm3 bone marrow nor the initial response to the induction regimen of 6-thioguanine, cytosine arabinoside, and daunorubicin (TAD). For remission duration a tendency towards a higher proportion of lung remissions was observed in patients with DNA aneuploidy.

Adolescent↗