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C M Payne

Publications and source records attributed to C M Payne.

At least 19 recordsLinked to original sources
PubMed1994

Programmed cell death of the normal human neutrophil: an in vitro model of senescence.

The present study provides experimental data which indicate that the neutrophil is ideal for studying programmed cell death or apoptosis in vitro. Neutrophils can be obtained from human peripheral blood in large numbers with minimal experimental manipulation and are easily separated from other leukocytes, providing nearly pure cell suspensions. The neutrophil life span in vitro is sufficiently short to allow observations to be made within eight hours after experimental manipulation. Neutrophils can also be easily maintained in serum-free, chemically defined media which can be systematically altered, thereby defining specific variables that influence the apoptotic process. Since the neutrophils do not need an exogenous trigger to undergo programmed cell death, it is also an excellent model to study senescence. It was determined from this study that neutrophils undergo apoptosis most efficiently at 37 degrees C, a temperature requirement for physiologic cell death. Neutrophils undergo apoptosis at a slightly faster rate and maintain membrane integrity better when incubated in a tissue culture medium (e.g., RPMI 1640) compared with a balanced salt solution (e.g., HBBB). Cycloheximide, an inhibitor of protein synthesis, was shown to accelerate apoptosis in a dose-dependent manner. The presence of Zn++ significantly decreased the rate of apoptosis, whereas the presence of Ca++ and Mg++ had no apparent effect. These studies indicate that the process of senescence, culminating in cell death, is subject to modulation by a variety of agents and experimental conditions. In addition, the ultrastructural features of neutrophils undergoing programmed cell death in vitro were compared in detail to those occurring in vivo and were found to be comparable.

Apoptosis↗
PubMed1994

Clinical paths for cardiac surgery patients: a multidisciplinary approach to quality improvement outcomes.

Implementation of clinical paths has resulted in a successful multidisciplinary approach for monitoring quality improvement outcomes in a select group of cardiovascular patients. This article defines clinical paths and explains their development, implementation, and evaluation. It also discusses how variances (which are defined as discrepancies between expected and actual events) were identified and how this information led to actions to improve patient outcomes. The roles of each health care professional are discussed in relation to clinical paths, and positive outcomes for the nurse, other health care professionals, and the institution are presented.

Clinical Protocols↗
PubMed1994

Insertional activation of cepA leads to high-level beta-lactamase expression in Bacteroides fragilis clinical isolates.

Bacteroides fragilis is an important opportunistic pathogen of humans and is resistant to many drugs commonly used to treat anaerobic infections, including beta-lactams. A strain set comprised of B. fragilis isolates producing either low or high levels of the endogenous cephalosporinase activity, CepA, has been described previously (M. B. Rogers, A. C. Parker, and C. J. Smith, Antimicrob. Agents Chemother. 37:2391-2400, 1993). Clones containing cepA genes from each of seven representative strains were isolated, and the DNA sequences were determined. Nucleotide sequence comparisons revealed that there were few differences between the cepA coding sequences of the low- and high-activity strains. The cepA coding sequences were cloned into an expression vector, pFD340, and analyzed in a B. fragilis 638 cepA mutant. The results of beta-lactamase assays and ampicillin MICs showed that there was no significant difference in the enzymatic activity of structural genes from the high- or low-activity strains. Comparison of sequences upstream of the cepA coding region revealed that 50 bp prior to the translation start codon, the sequence for high-activity strains change dramatically. This region of the high-activity strains shared extensive homology with IS21, suggesting that an insertion was responsible for the increased expression of cepA in these isolates. Northern (RNA) blot analysis of total RNA by using cepA-specific DNA probes supported the idea that differential cepA expression in low- and high-activity strains was controlled at the level of transcription. However, the insertion did not alter the cepA transcription start site, which occurred 27 bp upstream of the ATG translation start codon in both expression classes. Possible mechanisms of cepA activation are discussed.

Amino Acid Sequence↗
PubMed1993

Effect of regular consumption of oily fish compared with white fish on chronic plaque psoriasis.

The influence of dietary advice on the severity of chronic plaque psoriasis was studied in 18 patients. Medication was standardized in all patients who were advised to eat 170 g white fish daily for a 4 week run-in period. Then the patients were randomized either to continue with the white fish diet or to substitute 170 g oily fish daily for 6 weeks. At the end of this second period the diets were reversed for a further 6 weeks. The oily fish but not the white fish diet led to a modest clinical improvement (11% and 15%, P < 0.01) which was accompanied by a rise in plasma eicosapentaenoic acid (20:5n-3) concentrations. It is concluded that dietary advice to increase the daily intake of oily fish is a useful adjunct in the treatment of psoriasis. The fish that should be recommended include mackerel, sardine, salmon, pilchard, kipper and herring.

Adult↗
PubMed1992

Change in the frequency of apoptosis after low- and high-dose X-irradiation of human lymphocytes.

The purpose of the present study was to correlate the type and frequency of cell death in human lymphocytes receiving variable doses of X-irradiation. Monocyte-depleted lymphocyte fractions were exposed in vitro to variable doses of X-rays of 0-20 Gy (0-2000 rads) and incubated for 4 and 16 h. An assessment of the mode of cell death (apoptosis vs. classical necrosis) was carefully evaluated using a multidisciplinary approach using light, fluorescence and electron microscopy (EM), and dye exclusion assays. Eosin Y exclusion assays indicated the absence of classical necrosis occurring in short-term cultures (4 h postirradiation). An assessment of cell counts, however, revealed a mean decrease of 4% at 0 Gy and 13% at 10-20 Gy (1000-2000 rads). The predominant mode of cell death was apoptosis, but the percent apoptotic cells (determined by EM) did not parallel this increase in cell loss with increasing radiation and actually decreased at doses above 5 Gy (500 rads). The discrepancy between percent cell loss and percent apoptosis was explained by a proposed change in overall duration of the apoptotic process. In long-term cultures (16 h postirradiation), a combination of classical necrosis, classical apoptosis, and combined apoptosis and necrosis (secondary necrosis of apoptotic cells) was apparent and was associated with a marked decrease in viability. Irradiation effects on lymphocytes showing none of the morphologic features of apoptosis or classical necrosis in short-term culture were evidenced by an increase in nuclear lobation. The results of this study indicate that the vast majority of peripheral blood lymphocytes are radioresistant. The use of irradiation in an in vitro model to study the biochemical events of the apoptotic process is also evaluated.

Apoptosis↗
PubMed1991

A variant form of thrombasthenia.

We encountered two siblings with abnormal bruising since infancy. Studies revealed functional platelet defects characterized by a lack of platelet aggregation and adenosine triphosphate release on exposure to adenosine diphosphate and collagen as well as variable responses with ristocetin (at concentrations of less than or equal to 1.25 g/L) and arachidonic acid. In addition, little or no platelet aggregation was observed after exposure to hexadimethrine bromide (Polybrene), the calcium ionophore A23187, and the thromboxane/endoperoxide analogue U46619. The membrane proteins IIIa and Ib were present, as determined with monoclonal antibody testing, and no platelet-associated IgG was found. Platelet analysis with routine electron microscopy and ultrastructural cytochemistry revealed normal morphologic features and no deficiencies in the number of alpha granules dense bodies and other organelles. The platelet abnormality may represent a new variant of thrombasthenia.

Adenosine Diphosphate↗
PubMed1990

Six-year retrospective surveillance of gastroenteritis viruses identified at ten electron microscopy centers in the United States and Canada.

To identify the prevalence, seasonality and demographic characteristics of patients with viral gastroenteritis, we reviewed 6 years of retrospective data on viral agents of gastroenteritis screened by electron microscopy at 10 centers in the United States and Canada. From 52,691 individual electron microscopic observations, a virus was detected in 16% of specimens, and the yearly positive detection rate among centers ranged from 8 to 34%. Rotavirus was the agent most commonly observed (26 to 83%), followed by adenoviruses (8 to 27%, respiratory and enteric combined), and small round viruses (SRVs) (0 to 40%) which were second most common at two of the centers. Rotavirus and astrovirus detections occurred more often in the winter but seasonal trends in detection were not apparent for the other viruses. Of all astroviruses detected 64% were found in infants (less than 1 year); unlike the other agents studied SRVs were detected in a large percentage of infants (48%) and older children and adults (20%). Among hospitalized patients a majority of all astroviruses, caliciviruses and SRVs were detected 7 days or more after admission in contrast to both rotaviruses and adenoviruses which were more likely to be detected earlier. The data suggest that SRVs are common agents of gastroenteritis and may be important causes of nosocomial infections. Because of the relative insensitivity of direct electron microscopy as a screening method for SRVs, astroviruses and caliciviruses, these data probably underestimate the true prevalence of disease caused by these agents.

Adenoviruses, Human↗
PubMed1990

Ultrastructural morphometry in the diagnosis of Sézary syndrome.

Blood specimens from 87 patients and control subjects were prepared for electron microscopy and subjected to ultrastructural morphometric evaluation by using a computerized planimeter. A statistical comparison of means indicated that patients with Sézary syndrome could be distinguished from normal subjects and patients with reactive lymphocytosis, by using mean nuclear perimeter and form factor values. The lymphocytic nuclei from patients with infectious mononucleosis were more lobated on visual inspection than those from normal subjects; the difference in mean form factor values was statistically significant. The simple histogram method was most discriminatory and distinguished patients with Sézary syndrome from patients with other types of lymphoid leukemias and reactive lymphocytosis, including infectious mononucleosis. The histogram method could not, however, distinguish patients with Sézary syndrome from patients with T-cell chronic lymphocytic leukemia and Japanese T-cell leukemia. The use of bivariate graphic displays (plotting nuclear size and shape measurements) placed the lymphoid cells of the various types of lymphoproliferative disorders into distinct morphometric domains. Computerized morphometric techniques may, therefore, be of greater value when the range of possible diagnoses is large.

Adult↗
PubMed1990

Limitations of ZAF correction factors in the determination of calcium/phosphorus ratios: important forensic science considerations relevant to the analysis of bone fragments using scanning electron microscopy and energy-dispersive x-ray microanalysis.

A series of calcium phosphate standards having calcium/phosphorus (Ca/P) molar ratios of 0.50, 1.00, 1.50, and 1.67, respectively, was prepared for bulk specimen analysis using scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis (EDXA). The standards were mounted on carbon planchettes as either pure crystals or crystals embedded in epoxy resin. Ten different samples of each embedded and non-embedded standard were analyzed in a JEOL 100 CX electron microscope interfaced with a Kevex 8000 EDXA system using a lithium-drifted silicon detector and a multichannel analyzer. The Ca/P ratios were determined by calculating both net peak intensities without matrix corrections and atomic kappa-ratios using the MAGIC V computer program with ZAF correction factors for quantitative analysis. There was such extensive absorption of phosphorus X-rays in standards embedded in an epoxy matrix that the observed Ca/P ratios were statistically compatible with four different standards ranging in theoretical Ca/P ratios from 1.0 to 1.67. Although the non-embedded crystals showed a greater separation in the Ca/P ratios, both methods of preparation produced serious flaws in analysis. Direct application of the discovery of this caveat to the identification of suspected bone fragments for forensic science purposes is discussed.

Bone and Bones↗
PubMed1989

Ultrastructural morphometric analysis of papillary neoplasms: biological and diagnostic relevance.

Ten papillary adenocarcinomas of thyroid origin (P-Thy), ten papillary adenocarcinomas of ovarian origin (P-Ov), and eight papillary neoplasms of non-thyroid/non-ovarian origin (P-Other) were morphometrically compared using 19 distinct quantitative nuclear and nucleolar parameters as a database for diagnosis. The selected cases consisted of 16 primary and 12 metastatic neoplasms. It was determined that the P-Thy group had a significantly smaller nucleolar area (NuA) and nucleolar perimeter (NuP), and smaller SDs of nuclear area (NA), NuA, and NuP compared with the P-Ov and P-Other groups (P less than .05). The P-Ov group had a significantly smaller SD of NA compared with the P-Other group (P less than .05). The P-Ov group exhibited the greatest variability among the papillary neoplasms. Linear regression analysis indicated that in the P-Thy group alone there was a significant correlation between mean nuclear form factor (4 pi A/P2) and mean NuA (r = -.82; P less than .01), and mean NP and mean NuA (r = +.77; P less than .01). Linear regression analysis also indicated that in the P-Ov group alone, there was a significant correlation between mean NA and mean NuA (r = +.75; P less than .02). Morphometric domains were established using statistically significant sets of variables that distinguished between the groups. The application of three-dimensional computerized cluster analysis techniques indicated that the P-Thy group consistently had the smallest morphometric domains. It was concluded that ultrastructural morphometric analysis of papillary neoplasms has diagnostic potential and reveals interesting biological relationships among distinct nuclear features in the different groups of neoplasms.

Adenocarcinoma, Papillary↗
PubMed1989

Phylogenetic considerations of neurosecretory granule contents: role of nucleotides and basic hormone/transmitter packaging mechanisms.

The characteristics of neurosecretory granules include the presence of an acidic interior, a hyperosmolar concentration of granule solutes, the presence of chromogranin (CG) or CG-like soluble acidic proteins and a high content of nucleotides, predominantly ATP. The identification of "nucleotides" within the neuroendocrine "stem cells" of coelenterates (e.g. Hydra) has raised some interesting evolutionary questions as to the function of intragranular nucleotides. The chromaffin granules of adrenal medullary cells have been studied extensively, and are representative of the neurohormone/neurotransmitter packaging problems encountered in neurosecretory granules, in general. At the acid pH (5.7) of the interior of the chromaffin granule, ATP has three negative charges based on the pK value of the gamma-phosphate group. ATP can therefore interact with positively charged amines, acetylcholine and divalent cations, forming binary and ternary complexes. The results of nuclear magnetic resonance (NMR) spectroscopy indicate that the hyperosmolar solutes within the chromaffin granule exist in a viscous, but fluid state; one function of ATP could be to help lower the osmotic pressure of the granule contents through extensive, but weak, intermolecular bonding. In addition, ATP is an excellent buffer to help maintain a pH of 5.7 within the interior of the chromaffin granule. An acidic milieu contributes to neurohormone/neurotransmitter packaging and granule stability. The presence of nucleotides within neurosecretory granules cannot, however, be explained on the basis of the ability of ATP to simply reduce osmotic pressure, since insulin molecules exist in a crystalline phase, a condition which, by itself, could substantially reduce osmotic pressure; nucleotides, nevertheless, co-exist in these insulin cores. ATP and ATP metabolites such as ADP, AMP and adenosine, formed as a result of the action of ectonucleotidases, can have extensive extracellular trophic and feedback effects after secretion. Extracellular nucleotides and adenosine can function as neuromodulators, agonists and antagonists to inflammatory cells, and regulators of blood flow, etc. It is possible that intragranular nucleotides were retained through a billion or more years of evolution because of the importance of these trophic and feedback effects. Parts of the neuroscretory granule, such as the F1 subunit of the proton-translocating ATPase, can be traced back to the aerobic bacteria, vacuolar amine transport to yeast and a CG-like acidic protein to protozoan secretory granules (i.e., the trichocysts of Paramecia).

Animals↗
PubMed1989

Isoprinosine does not influence the natural history of herpes zoster or postherpetic neuralgia.

In a double-blind randomised trial, 38 elderly patients with acute herpes zoster received either isoprinosine (IP) or placebo. IP neither shortened the acute phase of herpes zoster nor prevented postherpetic neuralgia. Transient asymptomatic hyperuricaemia affected one third of IP treated patients. Shortcomings in study design and misleading interpretation of results are common in previously published clinical trials of herpes zoster and postherpetic neuralgia. Guidelines for future studies are proposed.

Aged↗
PubMed1989

Chorioretinal anastomoses in age-related macular degeneration.

Both eyes (obtained at autopsy) from a 79-year-old man with a history of age-related macular degeneration and glaucoma were studied. One eye was studied histologically using light microscopy and transmission electron microscopy. The other eye was prepared for scanning electron microscopy after injection of Batson's mixture into the ocular vasculature. Well-developed anastomoses between the retinal and choroidal circulation in the macular area and a pathologic tubular pattern of the choriocapillaris were found. This is an adaptation of the perifoveal circulation to changes in the fovea and a choroidal vascular response to damaged tissue.

Aged↗
PubMed1989

A comparative mathematical evaluation of contour irregularity using form factor and PERBAS, a new analytical shape factor.

Contour irregularity was mathematically evaluated using two different analytical shape factors: (1) "form factor" (FF), a conventional type of shape analysis formula defined by the formula 4 pi A/P2, and (2) the "PErimeter Ratio Before and After Smoothing" (PERBAS). PERBAS values are obtained by first "smoothing" a contour that contains one or more concavities; surface projections are connected using straight lines and include only tangent lines that do not interest the nucleus, resulting in a convex wrap. Perimeters before and after smoothing were obtained using a MOP-3 computerized image analyzer. Using a series of computer-generated images, it was determined that FF was more sensitive than PERBAS to simple deformations of shape (i.e., having no contour concavities) whereas PERBAS was more specific for surface "roughness" (i.e., contour having at least one concavity). As an application to cancer diagnosis, 6 cases of Burkitt's lymphoma (BL) and 14 cases of Burkitt's-like lymphoma (BLL) were compared for nuclear contour roughness using both shape factors. The BLL group could be distinguished from the BL group on the basis of mean PERBAS values (P = .029), but not on the basis of mean FF values (P = .093). The BL group had a mean PERBAS value of 1.051 +/- 0.023 and a mean FF value of 0.790 +/- 0.068. The BLL group had a mean PERBAS value of 1.093 +/- 0.054 and a mean FF value of 0.723 +/- 0.094. Mean FF and PERBAS values, plotted in a bivariate graphic display, established morphometric shape domains. BL cases occupied a significantly smaller shape domain than did the BLL cases, indicating a greater heterogeneity among nuclear shapes in the latter group. Shape discrimination, in general, was greatly increased when both shape factors were used; this has a great potential for determining cancer diagnosis and patient prognosis.

Burkitt Lymphoma↗
PubMed1989

Quantitative light and electron microscopic correlations of nuclear features in papillary thyroid and ovarian carcinomas.

The light microscopic (LM) and electron microscopic (EM) features of nuclear bodies and nucleoli were quantitatively compared in ten papillary carcinomas each of thyroid (PC-Thy) and ovarian (PC-Ovar) origins, along with eight nonthyroid, nonovarian papillary neoplasms from other organs (PN-Oth). In each neoplasm, 100 randomly selected nuclei were scored for the presence of characteristic nuclear bodies; these were defined at the LM level by the presence of a central density surrounded by a clear halo, which corresponded to four distinct quantifiable images at the EM level. Means (+/- standard deviations) of the nucleolar frequency factor, the nucleolar area and the computed total nucleolar area (the product of the nuclear frequency factor and the mean nucleolar area) were assessed for the EM images. The number of nuclear bodies was 11.9 +/- 10.7 for PC-Thy, 5.2 +/- 5.3 for PC-Ovar and 5.9 +/- 7.4 for PN-Oth; the means for PC-Thy and PC-Ovar were significantly different (P less than .03), as were the means for PC-Thy and PN-Oth (P less than .04). The nucleolar frequency factor was 0.60 +/- 0.19 for PC-Thy, 1.19 +/- 0.51 for PC-Ovar and 0.99 +/- 0.22 for PN-Oth; these means were significantly different for PC-Thy versus PC-Ovar (P less than .01) and for PC-Thy versus PN-Oth (P less than .001). The mean nucleolar area was 1.19 +/- 0.45 for PC-Thy, 1.91 +/- 0.92 for PC-Ovar and 1.94 +/- 0.76 for PN-Oth; the means were significantly different for PC-Thy and PC-Ovar (P less than .05) and for PC-Thy and PN-Oth (P less than .05). The computed total nucleolar area was 0.73 +/- 0.41 for PC-Thy, 2.17 +/- 1.09 for PC-Ovar and 1.94 +/- 1.00 for PN-Oth; these means were significantly different for PC-Thy versus PC-Ovar (P less than .001) and for PC-Thy versus PN-Oth (P less than .01). A comparison of the total number of nuclear bodies, as determined by both LM and EM, indicated a significant correlation for the PC-Ovar (P less than .01) and PN-Oth (P less than .001) groups using linear regression analysis.(ABSTRACT TRUNCATED AT 400 WORDS)

Carcinoma, Papillary↗