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At least 253 records · Page 14Linked to original sources
PubMed1992

Variation in reference cells for DNA analysis of paraffin-embedded tissue.

Selection of the diploid reference cells used in flow cytometric DNA analysis of paraffin-embedded tissue is inconsistent in the literature. To determine which types of cells were most suitable for use as reference cells, benign paraffin-embedded tissue was evaluated from nine randomly selected autopsies. Benign kidney, lymph node, gastrointestinal mucosa, laryngeal mucosa, bronchial mucosa, bladder mucosa, pancreas, and, when available, prostate tissue were studied. Ten paraffin-embedded surgical specimens also were studied. In the autopsy specimens, great variability in the mean peak channels was noted on intrapatient evaluation and even more variability was present when comparing similar organs (especially lymph nodes) from different patients. Similar results were obtained using lymph nodes from surgical specimens. It is concluded that the most suitable diploid reference cells for DNA analysis of paraffin-embedded tissue are the benign cells present in the paraffin tumor block that have been processed in the same way as the tumor cells.

Aged↗
PubMed1999

DNA analysis in microfabricated formats.

The use of microfabricated DNA analysis tools utilizing microfluidics will provide the next generation of inexpensive DNA diagnostics. It will also provide methodologies to measure gene expression in a massively parallel manner, eventually providing the methodologies to measure most or all the human genes of significance on a single chip. These technologies, including PCR analysis, electrophoresis and gene chips are described using examples from the archival literature.

Journal Article↗
PubMed1991

Characterization of conservatively resected renal tumors using automated image analysis DNA cytometry.

The DNA histograms of 57 conservatively resected renal tumors were studied using automated image analysis DNA cytometry (Leytas II). Forty-nine of the analyzed tumors were renal cell carcinomas, six were oncocytomas, one was an angiomyolipoma, and one was a renal cell adenoma. On the basis of their DNA histograms, diploid, tetraploid, and aneuploid tumors could be distinguished. Aneuploid tumors could be subtyped further according to the DNA content of the stem cell line as hyperdiploid, hypertriploid, or hypertetraploid. Eight of the tumors were characterized by a combination of diploid and hypertriploid stem cell lines. During a mean follow-up of 5 years, only the two patients with a pure hypertriploid tumor died of distant metastases. These results indicate that automated DNA image analysis cytometry is able to differentiate among several types of renal tumors with obviously different prognoses.

Adenoma↗
PubMedDate not supplied

Sonographic, cytogenetic and DNA analysis in four 69,XXX fetuses diagnosed in the second trimester.

OBJECTIVE: To describe the ultrasound findings and its relationship with the cytogenetic study and the origin of the extra haploid chromosome set in four 69,XXX cases. METHODS: Four pregnant women were referred because of abnormal 2nd trimester ultrasound. Karytoypes, FISH and DNA analysis were performed. RESULTS: All cases presented asymmetrical intrauterine growth retardation, marked oligohydramnios and placental alterations and showed a 69,XXX karyotype. In three cases, DNA analysis allowed to establish the origin of the extra haploid chromosome set. CONCLUSIONS: At least three fetuses had a maternal extra haploid chromosome set. Thus, it has been possible to establish the main ultrasonographic markers and to observe the survival of the fetus until the second trimester when they have a maternal origin.

Adult↗
PubMed1991

Prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency with DNA analysis.

Six families at risk of having a child with 21-hydroxylase deficiency (21-OHD) requested prenatal diagnosis by DNA analysis. This was performed by Southern hybridization mainly using the endonuclease-probe combination of TaqI-21-hydroxylase (21-OHase) complementary DNA (cDNA). In three families, the probands were found to have deletion of a 3.7 kb fragment corresponding to the functional 21-OHase gene (21-OHase B gene). In the three fetuses tested, genomic DNA extracted from the chorionic villi had the 3.7 kb fragment and all were judged to be unaffected. In the other three families, DNA analysis was uninformative in the detection of 21-OHD and was also unable to determine carrier status with 21-OHase cDNA. In one of these three families, however, linkage analysis detected restriction fragment length polymorphism (RFLP) with cDNA for the fourth component of the complement (C4).

Adrenal Hyperplasia, Congenital↗
PubMed1993

False aneuploidy in flow cytometric DNA analysis of paraffin embedded tissue: effects of Carnoy's fixation.

False aneuploidy was detected on flow cytometric DNA analysis of paraffin embedded axillary lymph nodes negative for tumor. It was hypothesized that "clearing" of axillary fat in Carnoy's solution to facilitate lymph node dissection might be responsible for false aneuploidy. Various tissues fixed overnight in Carnoy's were compared to formalin fixed paraffin embedded controls. Under these conditions no false aneuploid peaks were detected, but Carnoy's fixation did shift the G0/G1 histogram peak to the left, increase the G0/G1 CV and increase the S phase fraction relative to formalin fixed controls. It was then hypothesized that partial fixation of nodes in Carnoy's followed by formalin fixation might result in false aneuploid peaks. Twenty-two lymph nodes were partially fixed in Carnoy's for periods ranging from 5 to 60 min followed by complete fixation in formalin. Seven of these nodes did show false aneuploid peaks. By contrast, no aneuploidy was detected in formalin fixed controls. It was concluded that tissues in contact with Carnoy's solution may be a source of false aneuploidy and/or false elevation of S phase fraction. This reinforces the need for matched negative tissue controls for DNA analysis of paraffin embedded specimens whenever possible.

Acetates↗
PubMed1996

Barrett esophagus with dysplasia. Flow cytometric DNA analysis of routine, paraffin-embedded mucosal biopsies.

Flow cytometric DNA ploidy analysis has been reported to be more objective and sensitive than morphologic evaluation as a surveillance method in patients with Barrett esophagus (BE) for the development and progression of precancerous lesions. Such analyses are typically performed using fresh samples that require a separate or "jumbo" biopsy, are prone to false DNA aneuploidy if not promptly processed, and do not allow for retrospective studies. The feasibility of performing flow cytometric DNA analysis on paraffin-embedded biopsies was studied to circumvent some of these problems using 12 squamous esophageal mucosa with inflammation and 58 BE cases showing varying degrees of dysplasia. Among the BE cases, 12 had no dysplasia, 20 were indefinite for dysplasia, 14 had low grade dysplasia, and 12 had high grade dysplasia. Satisfactory histograms were obtained in 86% of the analyzed samples. Among cases with adequate histograms, DNA aneuploidy was identified in 77% with high grade dysplasia, 16% with low grade dysplasia, 23% of indefinite for dysplasia, and 0% without dysplasia. One of the esophagitis samples was also DNA aneuploid. Correlation of DNA aneuploidy and degree of dysplasia is highly significant (P = .001). The authors have demonstrated that routinely processed paraffin-embedded biopsies can be used for flow cytometric ploidy analysis. DNA aneuploidy was highly correlated with degree of dysplasia and serves as a quantitative prognostic indicator for prospective as well as retrospective studies of the evolution of BE to carcinoma.

Barrett Esophagus↗
PubMed1999

Flow cytometric DNA analysis is useful in detecting multiple genetic alterations in squamous cell carcinoma of the esophagus.

BACKGROUND: Although flow cytometric DNA analysis has been recognized to be a useful prognostic indicator for patients with squamous cell carcinoma of the esophagus, the biologic significance of DNA aneuploidy remains to be elucidated. METHODS: Twenty-five patients with squamous cell carcinoma of the esophagus who underwent a curative subtotal esophagectomy were divided into 2 groups according to the DNA ploidy pattern. Multiple genetic changes, including the gene amplification of bcl-1, epidermal growth factor receptor, and c-myc, and the loss of heterozygosity of multiple tumor suppressor genes, including retinoblastoma, mutated in colorectal carcinoma, adenomatous polyposis coli, and deleted in colorectal carcinoma, in each case were investigated and the frequency of genetic alterations compared between both groups. In addition, the clinical outcome of these patients was also investigated. RESULTS: Eleven of 15 cases in the aneuploid group demonstrated at least 1 genetic change (73.3%) whereas only 2 of 10 cases in the diploid group did so (20.0%) (P<0.05). Both cases in the diploid group with genetic alterations had only 1 genetic change of 7 tested genes whereas 9 of 11 cases in the aneuploid group had multiple genetic alterations. Patients in the aneuploid group also showed a more unfavorable prognosis than patients in the diploid group. CONCLUSIONS: Based on the findings of the current study, flow cytometric DNA analysis is considered to be useful for both detecting multiple genetic alterations and predicting the prognosis of patients with carcinoma of the esophagus.

Aged↗
PubMed1995

Novel methods of DNA analysis.

The need for improved ways to analyze nucleic acids for the tools of molecular biology to become more prevalent in the routine clinical laboratory has led to the creation of unique methods for DNA analysis. Automation of sequencing techniques can provide a more rapid turnaround for results and can be more cost effective for the diagnosis of genetic disease and cancer than conventional techniques. Miniaturization of sequencing on DNA chips should be even more effective than our current means and make screening for these diseases easier. Improved amplification techniques will increase the sensitivity of infectious disease detection, and new methods to label and detect DNA probes will help alleviate the need to use radionuclides. This article centers on the nature of some recent advances in DNA analysis and on their future application in the clinical laboratory.

Argon↗
PubMed1988

Flow cytometric DNA analysis in the diagnosis of lung tumors. A comparison with conventional methods.

The efficiency of flow cytometric (FCM) DNA analysis in the diagnosis of lung carcinoma was compared with that of conventional cytologic techniques on bronchial brushing and fine needle aspiration samples from 461 patients. The main advantage of FCM was the rapid delivery of results. Unfortunately, this was offset by a poor sensitivity in the detection of bronchial tumors. Nevertheless, DNA analysis may still prove useful in determining the prognosis and in evaluating the effects of chemotherapy on known tumor stem lines.

Biopsy, Needle↗
PubMed1990

DNA analysis using polymerase chain reactions in the families of children with cystic fibrosis.

The results of our experience in DNA analysis in cystic fibrosis families using polymerase chain reaction (PCR) is reported. Of the first 10 families studied, seven were fully informative using the probe KM19 and PCR. In the remaining three families, Southern blotting analysis and the probe pXV2c were required before full information was obtained in two and partial information in the other family. The methods used, the current place of PCR and the clinical relevance of DNA analysis are discussed.

Blotting, Southern↗
PubMed1992

A flow cytometric DNA analysis of giant cell tumors of bone including two cases with malignant transformation.

BACKGROUND AND METHODS: Flow cytometric DNA analysis was performed on 30 cases of giant cell tumor (GCT) of bone with the use of paraffin-embedded sections. RESULTS: According to the criteria of Huvos, they were classified histologically into three groups: Grade 1, 26 cases; Grade 2, 4 cases; and Grade 3, no cases. Among the Grade 1 cases, 21 were diploid and 5 were aneuploid. Of the four Grade 2 cases, three were diploid and one was aneuploid. Nine patients had local relapses. Among four patients with complications by lung metastases, two have remained well at 18 and 157 months with the metastases. The other two patients, who had Grade 1 DNA diploid GCT of the 11th thoracic spine, had malignant transformation (osteosarcoma) resulting from radiation therapy. In one patient, the primary lesion exposed to radiation and the lung lesions were diploid, but in the other patient both were found to be aneuploid at autopsy. No significant differences of S-phase fraction were observed between two different grade groups. There was no significant correlation among DNA ploidy, histologic grade, and the presence or absence of lung metastases. CONCLUSIONS: Based on this study, the DNA analysis has a limitation in predicting the biologic behavior of GCT.

Adolescent↗
PubMed1989

Histopathologic parameters and DNA analysis in colorectal adenocarcinomas.

Human colon adenocarcinomas have histological parameters that are clearly associated with prognosis. These include tumor grade, pattern of invasion, presence of lymphocytes, and vascular involvement by tumor. The latter remains controversial with respect to the relative importance of intramural and extramural vascular involvement. Some studies show a poor prognosis for intramural invasion of capillary size vascular channels by tumor. On the other hand, when veins are involved by tumor, the presence of tumor in large extramural veins appears to have a much more ominous effect than intramural tumor involvement of small veins. The results of DNA analysis of colorectal adenocarcinomas varied greatly depending on study methodology but several important points can be summarized: (1) higher stage tumors have a greater proportion of aneuploid tumors; (2) aneuploid tumors tend to have a higher growth rate (SPF) and poorer survival than diploid tumors; and (3) aneuploid tumors are associated with histological parameters indicative of a poor prognosis such as vascular invasion, but ploidy is not related to tumor grade. One of the major problems in drawing firm conclusions about the relationship of flow cytometric DNA measurements to prognosis is great variability among the reported studies. The types of variation appear to fall into two major categories: patient selection and technical problems. The former are especially relevant in retrospective studies in which there is poor patient definition (site, grade, stage, and other standard tumor definitions) and a bias for selecting early stage tumors which have improved survivals. The latter includes a spectrum of technical problems inherent in this widely but not necessarily uniformly applied laboratory procedure. This is particularly true for DNA analysis of nuclei removed from paraffin tissue blocks. For the most part, quality control measurements including cell yields, the efficiency of extraction or disaggregation of aneuploid cells, exclusion of non-neoplastic cells, and other features characteristic of the scientific method are seldom included in studies of DNA analysis of solid tumors. Hopefully, a consensus regarding optimum technical and analytic methods will evolve, followed by the careful definition of human colon cancer cohorts. The importance of further studies is suggested by the results of this review which indicated that the presence of an aneuploid cell population is associated with a less favorable prognosis for all colorectal tumors.

Adenocarcinoma↗
PubMed1987

Flow cytometric DNA analysis of adrenocortical tumors in children.

Flow cytometric DNA analysis of isolated nuclei was performed on 14 lesions occurring in ten children with adrenocortical tumors. Unimodal DNA content distributions were obtained from seven tumors occurring in patients without metastases 2 to 18 years after diagnosis. Abnormal DNA contents were detected in all four primary lesions, which subsequently metastasized, and in the tumor of one patient who was followed for less than 2 years. Paraffin and frozen preparations were virtually identical, as were the analyses of the primary, recurrent, and metastatic disease occurring in one patient. These observations suggest that DNA content abnormalities detected by flow cytometry correlate with metastases, and may provide an objective measure of the biologic potential of these tumors.

Adrenal Gland Neoplasms↗
PubMed1996

Validation of probe EFD52 (D17S26) for forensic DNA analysis.

Validation studies that meet TWGDAM (The Working Group on DNA Analysis Methods) and CAC (California Association of Criminalists) guidelines for RFLP (restriction fragment length polymorphism) analysis were performed with the DNA probe EFD52 (D17S26). These studies demonstrate that the probe EFD52 is suitable for forensic casework. No unexpected DNA banding patterns were obtained from controlled studies examining various tissues, sample consistency over many gels, mixtures of body fluids, various substrates, various contaminants and non-human DNA sources. Of all the animal DNAs tested, only one higher primate yielded a single band to EFD52 hybridization. The sensitivity of EFD52 was shown to be comparable to that of other forensic probes. Population frequency distribution tables were prepared from over 4000 alleles and two-locus studies were conducted on nine forensically useful probes. Black, White, Hispanic and Lumbee Indian populations were found to be in Hardy-Weinberg and linkage equilibrium. Comparisons between victim blood standards and epithelial fractions of mixed strains from sexual assault cases were used to demonstrate the robustness of the EFD52 probe in forensic casework.

Asian People↗
PubMed1991

Flow cytometric DNA analysis of hepatocellular carcinoma: preliminary report.

Flow cytometric DNA analysis was performed in 50 paraffin-embedded specimens of clinical hepatocellular carcinoma (HCC) after hepatic resections. The DNA distribution pattern was classified in two types, diploid and aneuploid, according to the degree of dispersion on the DNA histogram. The major DNA pattern of HCC in this report proved to be aneuploid (78%), although 22% of tumors revealed a diploid pattern. The serum alpha-fetoprotein level exceeded 40 ng/ml in 86.1% of the aneuploid tumors and in 13.9% of the diploid tumors (p less than 0.05). We found no correlation between DNA distribution and hepatitis B surface antigen positivity, the presence of liver cirrhosis or tumor size. Additionally we noted no significant correlation between the DNA pattern and survival rates in patients with HCC who underwent hepatic resection.

Adolescent↗
PubMed1991

Flow cytometric DNA analysis of stage D2 prostatic carcinoma.

Flow cytometric DNA analysis was performed on 34 samples of prostatic carcinoma patients with stage D2 disease to study the relationship between DNA ploidy pattern, Gleason sum score, and prognosis. Nuclei were extracted from paraffin-embedded needle biopsy specimens. The DNA ploidy pattern was diploid in 53% of the tumors, tetraploid in 38%, and aneuploid in 9%. A significant correlation between DNA ploidy pattern, Gleason sum score, and prognosis was not proved. It was considered that DNA ploidy pattern and Gleason sum score of limited primary lesion did not allow a prognosis of the patients with stage D2 prostatic carcinoma to be made.

Adenocarcinoma↗
PubMed1999

DNA analysis of Huntington's disease: five years of experience in Germany, Austria, and Switzerland.

OBJECTIVE: To review the direct DNA testing for Huntington's disease (HD) in Germany, Switzerland, and Austria from 1993 to 1997, and to analyze the population with regard to age structure, gender, and family history. METHODS: Twelve laboratories (nine in Germany, two in Austria, and one in Switzerland) recorded data pertaining to repeat number, gender, age at molecular diagnosis, and family history of probands. The molecular test was categorized as either diagnostic (for symptomatic individuals), presymptomatic (for individuals at risk), and prenatal (for pregnancies at risk). RESULTS: A total of 3,090 HD patients, 992 individuals at risk, and 24 fetuses were investigated using DNA analysis. The clinical diagnosis was confirmed in 65.6% of patients. A total of 38.5% of individuals at risk inherited an expanded CAG repeat. The female-to-male ratio showed a distinct predominance of women both in the diagnostic and presymptomatic groups. Of the fetuses tested, six were carriers of an expanded CAG repeat. Two pregnancies were interrupted; one pregnancy was not. No information about the parents' decision was obtained for the remaining three pregnancies. CONCLUSIONS: Approximately 20% of the estimated 10,000 HD patients living in Germany, Switzerland, and Austria have been identified by DNA analysis (total population, approximately 100 million; incidence of HD, 1:10,000). Assuming a ratio of HD patients to individuals at risk of 1:3, approximately 30,000 individuals are, in principle, eligible for a presymptomatic test. Less than 3 to 4% of individuals at risk have requested a presymptomatic test. This shows that the assumed enormous request of predictive testing has not occurred. More surprisingly, prenatal diagnoses were found to be rare.

Adult↗