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At least 19 recordsLinked to original sources
PubMedDate not supplied

Cerebrospinal fluid cytology: diagnostic accuracy and comparison of different techniques.

Cytologic examination of cerebrospinal fluid was performed in 1,021 patients, using Nuclepore and Millipore filter techniques. Positive findings were obtained in 89 cases, including 40 with primary central nervous system tumors, 24 with metastatic tumors and 25 with leukemic or lymphomatous involvement. When correlated with histologic findings, the overall detection rate was 32.2 per cent for primary tumors, 53.3 per cent for metastatic tumors and 65.8 per cent for leukemia and lymphoma. Highest degree of accuracy in the primary tumor group was achieved with medulloblastoma (61.9 per cent). Among metastatic tumors, those originating in the lung (70 per cent) and breast (83 per cent) were the one most often detected. Comparison of the two filter techniques indicated a slightly higher detection rate when the Millipore filter was used. The reasons for this are not entirely clear, but increased cellular yield with the Millipore filter may be an important factor. The cytocentrifuge method was found to be generally inferior to either of the filter techniques in quality of cell preservation. Our findings indicate that diagnostic usefulness of cerebrospinal cytology depends on collection and preparation methods as well as the anatomic distribution and biologic behavior of the lesions.

Cerebrospinal Fluid↗
PubMed1978

Tissue cultures from cerebrospinal fluid specimens in the study of human brain tumors.

The authors report a study in which 109 cerebrospinal fluid (CSF) specimens from patients with varying neurological disorders were incubated in tissue culture medium for 1, 3, and sometimes 7 days. Strict criteria for malignancy were applied to cells found at these intervals. In 35 patients with verified central nervous system neoplasms, eight cases had malignant cells and 11 others had "doubtful" cells by tissue-culture analysis. Thirty-three of these cases were also examined with standard millipore cytological techniques: six had malignant cells and four had "doubtful" cells. Of 50 cases with inflammatory or other non-neoplastic conditions, cells were cultured in 13. None was considered malignant by our criteria. Tissue culture of CSF has several potential benefits. Even with stringent criteria, it is possible to demonstrate the presence of unequivocally malignant cells in CSF by tissue culture. The systemic application of such criteria may eventually increase the positive identification of malignancies. Further, since these cells are growing, the degree of malignancy may be more accurately determined by a study of growth in culture. Such a study could not be done by conventional methods. Finally, tissue culture can help to guide therapy in certain instances in which a surgical biopsy cannot be obtained.

Brain Neoplasms↗
PubMedDate not supplied

An evaluation of cytologic sampling techniques. A comparative study.

False negative cervical cytology is primarily due to errors in sampling. It has been demonstrated that combined ectocervical and endocervical sampling techniques will improve the yield. A prospective study was done to compare ectocervical and combined sampling with a selective technique in which the examiner determines the location of the squamocolumnar junction and chooses the appropriate method. The results demonstrate that combined ectocervical and endocervical sampling significantly increases the number of positive Papanicolaou smears. Selecting which cervices should be samples ectocervically and which need combined sampling does not significantly improve the yield over ectocervical sampling alone. It is the conclusion of this study that both ectocervical and endocervical sampling should routinely be used.

Diagnosis, Differential↗
PubMedDate not supplied

Centrifugal Cytology, IV. The Prearation of fixed stained dispersions of gynecological cells.

The Centrifugal Cytology technique has been utilized to produce glutaraldehyde fixed stained dispersions of both conventional Ayre scrapes and Davis pipet (PAPette) samples. Light microscope studies of dispersions of both types of cells on conventional microscope slides indicated that both the tinctorial and morphological appearance of the cells after Papanicolaou staining was very similar to that observed with conventional smears and that the same criteria could be utilized with the Centrifugal Cytology dispersions to screen the cells for cancer as had previously been used with the smears. A preliminary study indicated that six out of six positives with no false negatives or false positives were found. The Centrifugal Cytology technique appears to have promise as a method for preparing suspension samples such as pipets of gynecologic cells. Scanning electron microscope studies reveal that the squamous epithelial cells are very thin and at least some of them are covered by a network structure.

Carcinoma, Squamous Cell↗
PubMed1978

[Sample technique in cytology (author's transl)].

Modern theory and experience question the reliability and suitability of sampling per judgment being the method for the evaluation of the percentage of cells in clinical cytology till now. For the reduction of this gap empirical studies were undertaken in order to receive proper estimates of blood smears. A simple method for the differential blood count is to take 30 or more strips of the width of the field of vision of the microscope perpendicular to the smearing direction as sampling units at random or by systemtaic selection with a random starting point. For the class of cells under consideration as well as for whole the cell population on the slide, the coefficient of variation of the mean of the cells within different strips has to be less than 0,1. Smears of a width of 10 mm instead of the usual 22 mm seems to be preferable. Under such conditions more than 1.000 cells are to be counted for a reliable estimate of the more frequent classes of cells. It is not supposed that this tedious method will be carried out by technicians but modern apparatus are presumed to give consistent estimates in such a way.

Blood Cells↗
PubMed1977

Malignancy grading of epithelial bladder tumours. Reproducibility of grading and comparison between forceps biopsy, aspiration biopsy and exfoliative cytology.

107 bladder tumours cystoscopically suspected to be malignant were examined morphologically by forceps biopsy, aspiration biopsy and exfoliative cytology. The malignancy was graded from 0 through 4. The reproducibility of each method was established, and was found to be 80%, 65% and 90%, respectively. Exfoliative cytology underestimated the malignancy grade as compared with histopathology (59% of the malignant tumours were not jduged as malignant in the cytological grading), but showed no tendency towards overestimation and gave no falsely postiive diagnoses of malignancy. It is concluded that diagnosis of bladder tumours requires both biopsy and cytological techniques, since they proved complementary in a number of cases. Grading by aspiration biopsy is less reliable but may be of benefit in selected cases where forceps biopsy is less suitable.

Biopsy↗
PubMed1979

Combined cycloheximide and 8-hydroxyquinoline pretreatment for study of plant chromosomes.

The actions of cycloheximide and 8-hydroxyquinoline on dividing cells of root meristems of Zea mays L. have been studied during the development of a new cytological technique for sugar cane (Saccharum) root tips. The determination of mitotic phase indices revealed that combined treatment with cycloheximide (70 ppm) plus 8-hydroxyquinoline (250 ppm) was superior to treatments with either chemical separately. After the combined treatment, the preparations contained nearly ten times more cells in prophase and metaphase that were suitable for chromosome counting than those given a single pretreatment with 8-hydroxyquinoline. This new pretreatment has been developed especially for chromosome studies in tropical grasses with a large number of small chromosomes. However, both chemicals are active in a wide range of plant species.

Chromosomes↗
PubMedDate not supplied

Cell yield obtained with various cytopreparatory techniques for urinary cytology.

Information concerning the main pitfalls of cytopreparatory techniques, e.g., cell loss, is of paramount importance for general acceptance of the routine use of urinary cytology. Therefore, we studied the cell yield obtained with five Papanicolaou and two May-Grünwald-Giemsa (MGG) smear techniques commonly used in diagnostic cytology laboratories, and compared the results with those obtained with the Millipore filter technique. All smear methods using wet fixation gave very low cell harvests (2-26%), and all methods using air drying gave high cell yield (55-95%), the spray fixation method giving intermediate results (about 40%). Since the morphometric studies showed that there was no preferential cell loss, the cells remaining on the slides can be considered representative of the original cell population. However, if the cell concentration of the urinary sample is extremely low, the Millipore filter and the albumin MGG methods, in both of which cell loss is minimal, are recommended. The results obtained with the spray fixation Papanicolaou method are quantitatively acceptable and qualitatively excellent.

Cell Count↗
PubMed1979

Qualitative cytological criteria for the validation of enzyme histochemical techniques.

Qualitative cytological criteria are concerned with the 'precision' of a histochemical reaction and form part of the general criteria for the validation of enzyme histochemical techniques. Three major problem areas are considered: (a) the general artifacts which interfere with the 'clean' appearance of the tissue sections; (b) the exact intracellular localization of the final reaction product and its relationship to specific subcellular compartments; (c) the problem of diffusion of enzymes or reaction products, or both, from their primary subcellular sites. Each of these points is discussed and illustrated by a few examples and the conclusion is drawn that by careful consideration of various criteria the enzyme cytochemical techniques can provide 'quantitative' information comparable to biochemical measurements of enzyme activity in tissue homogenates. In the example of localization of catalase with 3,3'-diaminobenzidine it is demonstrated that biochemical enzyme assays corrrelate closely with quantitative morphometric data obtained from cytochemical preparations through an automatic image analyser system.

Animals↗
PubMed1977

The correlation of routine cytology with the contents of carcinoembryonic antigen and alpha-fetoprotein in pleural and peritoneal effusions.

The levels of carcinoembryonic antigen (CEA) and of alpha-fetoprotein (AFP) were determined with radioimmunoassay in 63 samples of either pleural or peritoneal effusions. All samples were collected from 53 patients suspected for malignancy and were also studied with the routine cytological techniques. Elevated levels of CEA (above 20 ng/ml) were found in 14 out of 29 cytologically positive samples, in none of 6 cytologically suspected and of 14 cytologically negative samples. The highest levels of CEA (above 1,000 ng/ml) were found in samples from patients with gastrointestinal carcinomas, while negative results were most often found in lymphoreticular and ovarian malignancies. Elevated levels of AFP (above 5 ng/ml) were found in 9 samples (5 cytologically positive and 4 negative). Five of these exudates were negative for CEA. Positive results of AFP were most frequently found in samples derived from patients with secondary or primary liver tumours. The highest levels of AFP (6 and 30 ng/ml), were determined in samples of two hepatoma patients. The combined cytological and radioimmunological studies suggested malignancy in 52 out of 63 samples while cytology alone detected either neoplastic or suspected cells in 35 samples only.

Ascitic Fluid↗
PubMed1979

[Use of phase-contrast and interference-contrast microscopy for immediate cytological tests in gynaecological practice (author's transl)].

Vital cytological tests of cervical smears obtained from 1,083 patients in a gynaecological practice are reported. The smears had been taken in search for malignant changes, in addition to the need for appraisals of ovarian function and vaginal flora. Smears which produced suspicious colposcopic and vital cytological findings were restained by means of Papanicolaou stain. The diagnoses based on both methods were compared. The results have confirmed the vital cytological technique to be extremely suitable for functional and flora diagnosis, while the Papanicolaou method was found to be superior to vital cytology in cancer screening.

Cytodiagnosis↗
PubMed1979

Characterization of human T lymphocyte subpopulations (TG and T non G): cytologic examination and cytographic analysis.

Two T lymphocyte subpopulations were separated with an immunological method. In fact recently two T cell subsets with receptors for the Fc of IgM (TM) and of IgG (TG) respectively have been described. We have specifically separated TG and T non G lymphocytes by the rosetting technique. Cytological examination was performed on the two cell fractions: the results are in agreement with that already reported. Cytographic analysis was also carried out confirming the cytologic results. The possible practical implications of these acquisitions and those already applied are discussed.

Cell Separation↗
PubMedDate not supplied

Cell clusters in urinary cytology.

Clusters of cells in cytologic preparations from the urinary tract have been commented on repeatedly. To determine their significance we studied 88 patients with documented papillary carcinomas, Grades I-IV, who had cytologic examination of their urine. We defined two distinct cluster types, "rounded", and "papillary", which were easily distinguishable from artifactual excoriated cell aggregates. By cytologic techniques 64 per cent of the specimens were positive and 18 per cent suspicious for malignancy, with the lowest sensitivity for Grade I tumors, and the highest for Grade IV tumors. Clusters were observed in 39 per cent of the cases, and also were more common in the most undifferentiated tumors. However, many cases which were cytologically positive had no clusters, and in only one case were clusters present without other cytologic features of malignancy. It appears that the presence of cell clusters is not a more sensitive indicator of papillary lesions than usual cytologic criteria applied to single cells. Clusters may indicate a higher grade tumor.

Adult↗
PubMed2026

Analyzing Meiosis in Maize.

Meiosis is central to sexual reproduction and the main source of genetic diversity in plants. Understanding how meiotic processes are regulated has direct relevance to agriculture. As meiotic recombination is the vehicle of plant breeding, gaining the ability to influence recombination patterns can accelerate crop improvement. Maize is a powerful model for studying plant meiosis, thanks to its large chromosomes, well-developed genetics, and the availability of diverse cytogenetic and molecular tools. Insights gained from maize studies can extend to other species. In this review, we describe a variety of approaches for examining meiosis and meiotic recombination in maize. Cytological techniques, including protein immunolocalization and fluorescence in situ hybridization (FISH), enable visualization of chromosome structure and behavior, as well as crossover (CO) formation. Chromatin immunoprecipitation (ChIP) is used in meiosis research to determine locations of recombination proteins, identify recombination sites, and elucidate chromatin features, such as histone modifications. Quantification of COs at specific genomic sites through pollen typing by droplet digital PCR allows precise high-resolution measurement of recombination rates. Combining cytology, protein localization, and molecular assays provides a multiscale picture of meiosis, linking molecular mechanisms to chromosome behavior and, ultimately, to genetic variation.

Journal Article↗
PubMed1978

Cytotoxicity evaluation of root canal sealers by the tissue culture--agar overlay technique.

Ten commercially available root canal sealers were tested for cytotoxicity by the tissue culture--agar overlay method for periods of 0, 24, 48, 72, and 96 hours. All sealers manifested evidence of toxicity at every stage of testing. Some sealers which were markedly toxic at 0 hour showed reducing levels of toxicity out to 96 hours. Others remained highly toxic throughout the entirety of the experimental period.

Agar↗