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D C Allison

Publications and source records attributed to D C Allison.

At least 37 records · Page 2Linked to original sources
PubMed1989

Demonstration of the cell cycle positions of taxol-induced "asters" and "bundles" by sequential measurements of tubulin immunofluorescence, DNA content, and autoradiographic labeling of taxol-sensitive and -resistant cells.

We used reliable and relatively inexpensive equipment to make sequential sets of measurements of antitubulin immunofluorescence, Feulgen staining, and autoradiography on the same cells. This was done to evaluate tubulin conformations, DNA content, and [3H]-thymidine incorporation in cell lines sensitive (HL60) and resistant (K562) to the novel anti-tubulin chemotherapeutic agent taxol. Numbers of cells with microtubule bundles have been found to correlate with sensitivity to taxol by clonogenic assay for several leukemic cell lines. We have found that cells with "asters" produced by taxol exposure are in mitosis and that cells with taxol-induced "bundles" are in G0/G1, S, and G2 phases. We further found that S-phase cells with microtubule bundles in both sensitive (HL60) and resistant (K562) cell lines were able to incorporate [3H]-thymidine after 4-hr exposure to taxol. As microtubule bundles and asters occur in cells of the same cell cycle phases in both lines, we conclude that the greater frequency of cells with microtubule bundles reported for sensitive cells after taxol treatment cannot result from drug exclusion nor from different effects of the drug on cell microtubules in these two leukemic lines.

Alkaloids↗
PubMed1988

Comparison of absorption measurements of DNA stain content by utilizing video and scanning image cytometers.

After staining with the Feulgen reaction, the DNA stain contents of 155 mouse bone marrow cells and 22 adjacent chicken erythrocytes were measured by absorption image cytometry by utilizing two different systems--a scanning cytometer and a video cytometer. In the scanning cytometer (M85 microdensitometer, Vickers Instruments, Malden, MA), a spot of light was scanned across the cell. In the video cytometer (TAS Plus, E. Leitz, Rockleigh, NJ), the microscope field, which may contain several nuclei, was imaged onto a Plumbicon video camera. With each system, cells were scanned, digitized into their elementary pixels, and analyzed to determine their integrated absorbance. Comparison of the DNA stain contents of the same G0/G1 bone marrow cells and chicken erythrocytes, as measured by video and scanning cytometry, showed that both techniques gave comparable results; scanning cytometry is more precise. The coefficients of variation of the measurements for the G0/G1 bone marrow cells and for the chicken erythrocytes were 5.9% and 7.0%, respectively, when measured by video cytometry at the absorption peak (584 nm), compared to 4.1% and 3.5%, respectively, for the same cells when measured by scanning cytometry off the absorption peak (615 nm). The video-based measurements were relatively lower than the scanning measurements for darkly stained cells; this suggests that glare and other optical errors which increase with stain darkness caused greater systematic errors in the video cytometer than they did in the scanning cytometer.

Animals↗
PubMed1988

The cytogenetic and hepatotoxic effects of dioxin on mouse liver cells.

The cytogenetic and hepatotoxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on mouse liver cells were investigated. Male C57BL/6J strain mice, which have TCDD receptors, were given single intraperitoneal injections of 25, 37.5, 75 and 150 micrograms of TCDD/kg body weight or corn oil carrier alone. Two-thirds hepatectomies were carried out at 1 or 7 days after injection and chromosomal aberrations and mitotic indexes of the regenerating hepatocytes were scored 54 hr after hepatectomy. Liver sections from additional intact mice were studied for TCDD-hepatotoxicity at 1, 7 and 30 days after injection. The three high doses of TCDD caused hepatotoxicity with necrosis of liver cells and focal architectural collapse by 30 days after injection. No evidence was obtained of an increase in the frequency of chromosomal structural aberrations at doses that allowed sufficient mitotic activity for cytogenetic evaluation. We conclude that TCDD is not a clastogen for mouse hepatocytes, although high doses cause marked hepatocellular necrosis.

Animals↗
PubMed1988

Analysis of techniques and results in 347 consecutive colon anastomoses.

We have reported our experience with 347 consecutive colon anastomoses in 321 patients seen over an 8 year period. The overall anastomotic failure, mortality, and complication rates were 1.4, 2, and 10 percent, respectively, for the entire series. The complication and death rates were significantly higher in patients whose anastomoses were completed as part of an emergency procedure. Even though various one- and two-layer inverting techniques, suture materials, and staples were used, we could not identify any one method as being clearly superior in preventing anastomotic complications, although the results do suggest that some caution may be appropriate before mechanical stapling devices are universally applied. The results support that adherence to accepted surgical principles of reducing the solid content and fecal flora of the colon prior to operation, insuring an excellent blood supply to both bowel ends, even approximation of the bowel ends with inverting sutures which include the submucosal layer of the bowel, absence of tension, meticulous hemostasis, and avoidance of anastomosis in the presence of peritonitis are the primary means of avoiding dehiscence of colon anastomoses.

Adolescent↗
PubMed1987

Cytophotometric determination of unscheduled DNA synthesis.

We describe a cytophotometric assay for unscheduled DNA synthesis (UDS) in asynchronously growing cells. Monolayer cultures of human HEp-2 and mouse MCa-11 cells were incubated with the carcinogen methyl-methane sulfonate (MMS), as well as with hydroxyurea and (3H)thymidine. Slides were prepared, and the DNA contents and areas of nuclei were measured by absorption cytophotometry. The labeling of the nuclei, determined on the basis of their DNA content to be in G0/G1, was selectively measured after the preparation of autoradiographs. The labeling of the G0/G1 cells increased with increasing doses of MMS. We also found that the increased nuclear labeling after MMS treatment was not due to induction of replicative DNA synthesis or selective destruction of G0/G1 cells. The results of this assay compared favorably with a standard biochemical method for measuring unscheduled DNA synthesis by benzoylated naphthoylated DEAE cellulose chromatography.

Animals↗
PubMed1987

Combined flow and absorption DNA measurements of [3H]TdR-labelled tumour cells. I. Studies of MCa-11 cells grown as tumours in vivo and as exponential cultures in vitro.

Flow cytometry of cellular DNA content provides rapid estimates of DNA distributions, i.e. the proportions of cells in the different phases of the cell cycle. Measurements of DNA alone, however, yield no kinetic information and can make it difficult to resolve the cell cycle distributions of normal and transformed cells present in tumour biopsy specimens. The use of absorption cytophotometry of the Feulgen DNA content and [3H]TdR labelling of the same nuclei provides objective criteria to distinguish the ranges of DNA content for G0/G1, S, and G2/M cells. We now report on a study in which we combined flow and absorption cytometry to resolve the cell cycle distributions of host and tumour cells present in biopsy specimens of MCa-11 mouse mammary tumours labelled in vivo for 0.5 hr with [3H]TdR. A similar analysis of exponential monolayer cultures, labelled for 5 min with [3H]TdR under pulse-chase conditions, revealed a highly synchronous traversal of almost all cells through the different phases of the cell cycle. Combination of the flow and absorption methods also allowed us to detect G2 tumour cells in vivo and a minor tumour stem-line in vitro, to show that these two techniques are complementary and yield new information when they are combined.

Absorption↗
PubMed1986

Alterations in the DNA metabolism of MCa-11 mouse mammary tumor cells grown in vivo and in vitro.

Mouse mammary carcinoma (MCa-11) cells were grown in vitro in exponential, plateau-fed, and starved monolayer cultures or as 100-, 250-, and 500-microns tissue culture spheroids, and in vivo as small (4-mm diameter) and large (12-mm diameter) tumors. In all of these forms, the growth rates of the MCa-11 cells were found to decrease after an initial rapid proliferation of a relatively small number of cells. The DNA distributions of these cells during different rates of growth in vitro and in vivo, as well as the proportion and intensity of labeling of the S-phase cells with [3H]thymidine and [3H]deoxyuridine, were measured by flow and absorption cytometry. We found that significant numbers of MCa-11 cells remained in S phase, even after the growth rates in vivo and in vitro had slowed. However, as growth rates decreased, the intensity and proportion of S-phase cells labeled with exogenous DNA precursors decreased. We conclude that progressive alterations, including possible slowing and cessation, of replicative DNA synthesis occur in S-phase tumor cells as the metabolic constraints on tumor growth are increased.

Animals↗
PubMed1985

Hepatotoxic doses of dioxin do not damage mouse bone marrow chromosomes.

We report on a study of the cytogenetic and hepatotoxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Mice of the C57B1/6J (with high-affinity TCDD receptor) or DBA/2J (with low-affinity TCDD receptor) strains were given single intraperitoneal injections of 50, 100 or 150 micrograms of TCDD/kg body weight. At various times (8-48 h) after injection, we examined bone marrow cells for cytogenetic effects by performing structural aberration, sister-chromatid exchange, and micronucleus tests. 1 month after exposure, liver sections were studied for hepatotoxic effects. We found no evidence of chromosome damage by TCDD given in doses that cause liver damage in both strains of mice.

Animals↗
PubMed1985

An improved method of preparing nuclei for absorption cytophotometry.

An improved method of isolating nuclei from tissue for Feulgen-DNA measurements has been developed. The optimal nuclear isolation medium (NIM) was found to be a solution of 2% polyethylene glycol (PEG) and 0.6% NP40 in phosphate-buffered saline. The disaggregation procedure consists of gentle mechanical disruption of the tissues, followed by a 10 min incubation in the NIM at room temperature. The mixture is then syringed four times through a 27-gauge needle, and the nuclei are placed onto slides with a cytocentrifuge. Nuclei prepared in NIM without PEG had obvious DNA leakage and tended to form clumps. Addition of PEG to the NIM led to separation of nuclei without any DNA leakage, thus greatly increasing the accuracy of the DNA cytophotometry results. G0/G1 nuclei at the appropriate ploidy levels were found for non-transformed and transformed tissues prepared with this technique. In addition, S-phase liver nuclei prepared in this manner showed the expected incorporation of (3H) thymidine after a 1/2 hr pulse in vivo.

Animals↗
PubMed1985

Variations in the [3H]thymidine labeling of S-phase cells in solid mouse tumors.

To determine whether all tumor S-phase cells incorporate [3H]thymidine, we labeled the cells in three mouse tumors (MCa-11, colon-26, and colon-51) in vivo for 1/2 h with [3H]thymidine (10 microCi/g of body weight). Cells from the tumors, as well as control cells from the bone marrows of the tumor-bearing mice, were then placed onto slides and Feulgen stained. The positions of these Feulgen-stained cells were mapped with a computerized scanning stage, and their nuclear DNA content and nuclear areas were determined by absorption cytophotometry. Next, the slides were processed for autoradiography and exposed for 32 or 64 days to obtain plateau labeling. The cells were then relocated, and the areas of the autoradiographic grains over each nucleus were measured. We found that 99% of the S-phase bone marrow cells were labeled. The 5-mm tumors, however, showed a wide range of S-phase labeling, with 94, 89, and 85% of the MCa-11, colon-51, and colon-26 S-phase cells, respectively, being labeled. The same mice bearing both 5- and 20-mm MCa-11 tumors, however, showed 95 and 57% labeling of the S-phase cells in the small and large tumors, respectively. These results show that the [3H]thymidine labeling of S-phase cells varies greatly for experimental mouse tumors of different size and type, and they suggest that "labeling index" and flow cytometric DNA measurements may not give valid estimates of the actual proportions of cycling S-phase cells in such tumors.

Animals↗
PubMed1984

Increased accuracy and speed of absorption cytometric DNA measurements by automatic corrections for nuclear darkness.

We have developed a method of calculating the average local absorbance (ALA) of a nucleus from the integrated nuclear absorbance and area. One can use the ALA, along with nuclear areas measured at different point absorbance thresholds, to determine whether a nucleus is stained too lightly or too darkly for accurate absorption measurements; this allows selection of an optimal light wavelength for the performance of these measurements. The ALA can also be used for automatic and instantaneous correction of integrated absorbance values from darkly stained cells. This allows the rapid measurement of the integrated absorbances of a large number of nuclei that are heterogeneous in stain intensity. Coefficients of variation of approximately 3% are obtained for the integrated absorbances of nuclei of nontransformed G0/G1 cells. This correction method can be applied with any image densitometer that generates both integrated absorbance and area values.

Animals↗
PubMed1984

Computerized measurement of the DNA content, areas, and autoradiographic grains of the same nuclei: demonstration that lightly (3H)thymidine-labeled bone marrow cells are predominantly in G0/G1 and G2.

A computerized "flying spot" microdensitometer and scanning stage have been combined to measure the cellular DNA content, nuclear areas, and autoradiographic grain areas of the same cells. The slide positions of the Feulgen-stained, (3H)thymidine-labeled cells are mapped with the computerized stage, and nuclear DNA content and areas are then determined by integral absorbance measurements at 588 nm. Following autoradiograph preparation, the cells are relocated and the areas of the autoradiographic grains over each nucleus are measured at a light wavelength (625 nm) and an optical density setting (greater than 0.10) that do not detect the Feulgen stain. The microcomputer calculates the portion of each nucleus covered with autoradiographic grains (grain area proportion, GAP), and it links the GAP value to the DNA content of each nucleus in the computer file for subsequent sorting and analysis. By using this system in a study of mouse bone marrow cells labeled in vivo with (3H)thymidine, we found that all S-phase cells were clearly labeled after 8 or more days of autoradiographic exposure. Prolonged exposures (up to 64 days) led to detection of lightly labeled cells (0.1 less than GAP less than 0.8) with G1/G0 and G2 DNA content.

Animals↗
PubMed1984

Colonic perforation as a complication of peritoneovenous shunt: a case report.

Perforation of the left colon by a peritoneovenous shunt was diagnosed in a patient who had systemic sepsis 6 years after placement of the shunt. The patient was treated successfully by direct tapping of the shunt, which demonstrated enteric flora, and by an exploratory laparotomy, removal of the shunt, bowel resection, and colostomy. Although visceral perforations have been described with ventriculo-peritoneal shunts, we found no published report of an enteric fistula from a peritoneovenous shunt. This complication should be considered in patients with shunt malfunction.

Ascites↗
PubMed1983

Morbidity and mortality after operation in nonbleeding cirrhotic patients.

The purpose of this study has been to provide information on the mortality and morbidity rates for operation on nonbleeding cirrhotic patients and to identify factors that portend a grave prognosis. A review of 102 cirrhotic patients who underwent a variety of major therapeutic operations revealed a mortality rate of 19.6 percent. Mortality rates were significantly increased (p less than 0.05) by emergency operation (45.8 percent), gastrointestinal related operation (27.6 percent), ascites (37.5 percent), a bilirubin concentration greater than 3.5 mg (44.4 percent), a prothrombin time increase greater than 2 seconds (36.1 percent), a partial thromboplastin time increase greater than 2 seconds (50 percent), an alkaline phosphatase concentration greater than 70 units (40.9 percent), an operative blood loss greater than 1,000 ml (33.3 percent), and the presence of one or more postoperative complications (39.6 percent). Mortality rates were not increased after extremity, genitourinary, or gynecologic operations, an albumin concentration less than 3 g, a serum glutamic oxalacetic transaminase concentration greater than 40 units, hepatomegaly, and a history of previous gastrointestinal bleeding. When significant risk factors were added, mortality rates were significantly associated (p less than 0.001): zero to one factors 5.1 percent, two to three factors 19.4 percent, four to five factors 33.3 percent, and more than six factors 66.7 percent. The complication rate was 47.1 percent and included liver failure (42.2 percent), sepsis (18.6 percent), and bleeding (8.8 percent). Thus, in cirrhotic patients a clear need for operation must exist, liver function must be optimized preoperatively, and the most simple and expeditious procedure must be performed to avoid excessive blood loss and postoperative complications.

Adult↗
PubMed1983

Cytophotometric measurement of the cellular DNA content of [3H]thymidine-labelled spheroids. Demonstration that some non-labelled cells have S and G2 DNA content.

Spheroids from the V279-171b and MCa-11 cell lines were incubated continuously for 24 hr in [3H]thymidine for labelling of the outer cells of the viable rim. The spheroids were dispersed into single cells, and the DNA content of photomapped cells was measured by absorption cytophotometry. Autoradiographs were then prepared from which we ascertained cellular labelling. For spheroids of both cell lines, we found a larger proportion of cells with a G0/G1 DNA content among the non-labelled inner spheroid cells than among the labelled outer cells (P less than 0.001). This block of non-labelled spheroid cells in G0/G1 was not a cell cycle perturbation caused by the isotope for the MCa-11 spheroids. Approximately 8% of non labelled MCa-11 spheroid cells had S/G2 DNA content, suggesting that non-cycling cells in spheroids may be blocked in S and G2 as well as in the G0/G1 phase of the cell cycle.

Animals↗
PubMed1981

Increased accuracy of absorption cytophotometric DNA values by control of stain intensity.

A method of improving absorption cytophotometric cellular DNA values by making measurements on Feulgenstained cells at optimal stain absorbances has been developed. Stain intensity can be controlled either by alteration of the Feulgen staining reaction or by selection of "off-peak" wavelengths of light for cytometry. The use of chicken red blood cells as an internal standard, and of a computerized cytometer for the measurements, allows selection of the appropriate off-peak light wavelengths, correction for staining variability at different sites on the same slide, and rapid calculation of cellular DNA values. Cytometry can also be performed at controlled absorbance levels on autoradiographs of 3H-thymidine-labeled cells to allow direct study of the DNA content of nonlabeled G1/G0 and G2/M cells. Use of this technique on mixtures of mouse thymocytes, spleen cells, bone marrow cells, and liver cells gave essentially identical values for G1/G0 cellular DNA content, with coefficients of variation of less than 3%.

Animals↗
PubMed1980

Use of a trypan blue assay to measure the deoxyribonucleic acid content and radioactive labeling of viable cells.

A simple method of determining cellular viability, DNA content, and isotopic labeling is described. Cells are sedimented onto slides and fixed in a mixture of trypan blue and paraformaldehyde which stains nonviable cells a dark blue color, whereas viable cells exclude the dye. The staining pattern is stable for at least 6 months and persists after the Feulgen reaction, allowing the selection of viable cells for cytophotometric DNA determinations. We ascertained cellular incorporation of a 3H-thymidine label by photomapping cells prior to cytophotometry and relocating these cells after preparation of autoradiographs. The method gives accurate quantitative DNA and labeling values of mouse thymocytes labeled in vitro and may be of value in studies of tumors containing a large proportion of necrotic cells.

Animals↗