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W H Anderson

Publications and source records attributed to W H Anderson.

At least 37 records · Page 2Linked to original sources
PubMed1994

Hydrogen peroxide regulates phospholipase D-mediated hydrolysis of phosphatidylethanolamine and phosphatidylcholine by different mechanisms in NIH 3T3 fibroblasts.

A major goal of this work was to determine in NIH 3T3 fibroblasts whether the recently described effects of H2O2 on phospholipase D-mediated hydrolysis of phosphatidylethanolamine (PtdEtn) and phosphatidylcholine (PtdCho) are mediated by similar or different mechanisms. While exposure of NIH 3T3 fibroblasts to H2O2 stimulated the hydrolysis of both PtdEtn and PtdCho, the following important differences were noted: (i) prolonged (24 h) treatment of fibroblasts with 400 nM phorbol 12-myristate 13-acetate (PMA) blocked the stimulatory effect of H2O2 on PtdEtn, but not on PtdCho, hydrolysis; (ii) PMA-induced hydrolysis of PtdEtn, but not PtdCho, was inhibited by H2O2; (iii) the stimulatory effect of H2O2 was additive with that of sphingosine or staurosporine, inhibitors of protein kinase C, on the hydrolysis of PtdCho, but not PtdEtn; (iv) with membranes isolated from H2O2-treated fibroblasts, the hydrolysis of PtdCho, but not PtdEtn, was increased compared to values obtained with control membranes. These results imply that H2O2 regulates PtdEtn and PtdCho hydrolysis by different mechanisms. Stimulation of PtdEtn hydrolysis by H2O2, sphingosine, and staurosporine may commonly involve, at least in part, neutralization of an inhibitory protein kinase C isozyme.

3T3 Cells↗
PubMed1993

Carcinogens stimulate phosphorylation of ethanolamine derived from increased hydrolysis of phosphatidylethanolamine in C3H/101/2 fibroblasts.

Many human tumors contain high concentrations of ethanolamine phosphate (EtnP). An important question is whether increased formation of EtnP is merely the consequence of cell transformation, or is it associated with the process of carcinogenesis. Here we show that in C3H/10T1/2 embryonic fibroblasts, an established cellular model for the study of carcinogenesis, the environmental carcinogens, 7,12-dimethylbenz[a]anthracene (DMBA) and benzo[a]pyrene (B[a]P) (0.1-1 microgram/ml concentration; 24 h treatment), stimulate phosphorylation of ethanolamine derived from increased hydrolysis of phosphatidylethanolamine. The results suggest that increased formation of EtnP is associated with the early stages of carcinogenesis. This observation may have prognostic value.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1993

Elicitation of a predominantly lambda light chain-bearing antibody response in BALB/c mice to a novel bifunctional aminocarboxylate chelating agent.

A panel of murine monoclonal antibodies has been raised against the aminocarboxylate bifunctional chelating agent PA-DOTA complexed with Samarium. Ninety percent of the antibodies (43 of 48) used a lambda light chain. The binding specificity of 11 of the antibodies was examined by competition assays using several structurally related aminocarboxylate chelating agents containing different metals. Most of the antibodies are directed against the macrocycle ring of PA-DOTA and require the presence of a metal within the structure for binding.

Animals↗
PubMed1993

High-resolution CT in simple coal workers' pneumoconiosis. Lack of correlation with pulmonary function tests and arterial blood gas values.

We examined 21 miners by means of standard chest radiography, high-resolution computerized tomography (HRCT), pulmonary function tests, and resting arterial blood gas levels. Using the ILO/UC classification of pneumoconiosis, 7 miners had category 1/0 or 2/1 simple coal workers' pneumoconiosis (CWP). By HRCT, nodules were identified in 12 miners; 4 of 9 were classified as category 0/0 CWP; 2 of 5, 0/1 CWP; 5 of 6, 1/0 CWP; and 1 of 1, 2/1 CWP by chest radiograph. Focal emphysema was identified by HRCT in 7 miners; 4 of 9 were classified as 0/0 CWP; 2 of 5, 0/1 CWP; and 1 of 6, 1/0 CWP by standard chest radiography. Four miners with definite nodules confirmed by HRCT had focal emphysema, while three without nodules had focal emphysema. Pulmonary function testing was not different between miners with or without CWP by standard chest radiography, nor was it different between miners with or without definite nodules evidenced by HRCT. No difference in resting oxygenation was found between any group of miners. The presence of focal emphysema confirmed by HRCT did not significantly affect pulmonary function tests on resting arterial blood gas values. There was, however, a significantly lower FEV1 and mean forced expiratory flow during the middle half of forced vital capacity with lifetime nonsmoking miners. The presence of CWP on chest radiography was significantly correlated with smoking cigarettes but not the years of mining. The presence of nodules on HRCT approached a significant correlation with cigarette smoking, but focal emphysema did not. For detecting evidence of coal dust accumulation in lung parenchyma and identifying focal emphysema, HRCT was more sensitive than standard chest radiography. However, despite earlier detection of parenchymal abnormalities, abnormal pulmonary function attributable to coal dust could not be identified.

Blood Gas Analysis↗
PubMed1992

Enhancement of storage phosphor plate images: a C-language program.

A C-language software program has been developed for emulating the image enhancement processing of a storage phosphor plate system. This software has been implemented on a VAX 3400 computer. There are 2,100 lines of C-language code in the program. There are seven parameters used to specify the degree of enhancement. The software is being implemented on a single accelerator board.

Algorithms↗
PubMed1992

Impact of arterial blood gas analysis in disability evaluation of the bituminous coal miner with simple pneumoconiosis.

The Department of Labor has set guidelines for the use of resting arterial blood gas analysis in determination of total and permanent disability for coal workers' pneumoconiosis. To determine the prevalence with which bituminous coal miners fall below the arterial tensions of both oxygen and carbon dioxide published in the Federal Register, we studied 1012 miners who had both reproducible spirometry and arterial blood gas analysis as part of their disability evaluation. Eighty-seven percent of impaired miners could be identified by the spirometric criteria. Thirteen percent of impaired bituminous coal miners had acceptable pulmonary function but were eligible for black lung benefits by the blood gas guidelines. This population would have been missed if blood gas analysis were excluded from the evaluation process. On the other hand, approximately 25% of the blood gas analyses that were performed could be eliminated if a policy was adopted to do this test only on miners with spirometry that exceed the federal guidelines.

Carbon Dioxide↗
PubMed1992

The mandibular third molar position as a predictive criteria for risk for pericoronitis: a retrospective study.

During the 6-month period from mid February 1988 to mid August 1988, 148 patients presented with 154 diagnosed cases of mandibular third molar pericoronitis. All patients were members of the recruit population stationed at the Recruit Training Command, Great Lakes, Illinois. Selected clinical parameters relating to the orientation and eruption status of these third molars were collected and analyzed. The goal was to obtain a predictive clinical profile of the impacted mandibular third molar (MTM) at greatest risk for pericoronitis in the young naval and Marine Corps personnel. The majority of pericoronitis cases, 120 of 148 or 81.0%, involved vertically oriented MTMs; of this total, 79.1% were erupted to the approximate height of the occlusal plane of the arch. The remaining 20.9% were at or below the height of contour of the adjacent tooth. Mesioangular impacted MTMs accounted for only 11.2% of pericoronitis cases. The remaining cases comprised distoangular and horizontally impacted MTMs (3.4% and 3.8%, respectively). Involvement by impinging maxillary dentition was observed in 39.7% of the vertically oriented MTMs, 56.2% of the mesioangular oriented MTMs, 40.0% of the distoangular MTMs, and 14.0% of the horizontally impacted MTMs. The mean value for occlusal coverage by a soft tissue operculum observed for all MTMs in this study was 49%. In the population studied, risk for pericoronitis appears to increase with greater vertical orientation and height of eruption. The absence of impinging maxillary dentition did not eliminate the risk of mandibular third molar pericoronitis. These data have implications for targeting treatment needs of naval and Marine Corps personnel who may be without dental support for extended periods of time.

Adult↗
PubMed1991

A rapid method for the preparation of yeast for immunoelectron microscopy using Lowicryl HM-20.

We describe a fixation and embedding procedure for the yeast Saccharomyces cerevisiae using Lowicryl HM-20 which is rapid, gives excellent fixation, and avoids the low temperature handling normally associated with embedding in this resin. This procedure yields superior structural preservation when compared to the commonly used rapid embedding procedure which employs Lowicryl K4M. We demonstrate that sections prepared using our rapid procedure are suitable for use in immunogold labelling experiments.

Acrylic Resins↗
PubMed1991

The severity of diabetes is a major determinant of myocardial damage in the rat.

The severity of insulin-dependent diabetes mellitus had a marked effect upon the development of myocardial sequelae in the rat. Even with the same degree of hyperglycemia, glycosuria, polydipsia, and polyuria, moderately diabetic animals did not develop the degenerative ultrastructural changes seen in myocardium from more severely diabetic rats. These included decreased cardiocyte size, loss and disorganization of myofibrils, and loss of sarcoplasmic reticulum and transverse tubules. Since hyperglycemia and glycosuria are frequently used as the primary, and often sole, criteria for identifying diabetes in experimental animals, this study demonstrates the need to more specifically define the severity of the disease in studies of the heart.

Animals↗
PubMed1991

Tuberculosis in the intensive care unit: a chemotherapeutic controversy.

A survey of 150 practicing pulmonary physicians was conducted to determine chemotherapy preferences for the treatment of the patient suffering respiratory insufficiency secondary to active nonmiliary tuberculosis. An equal sample was selected from both the private sector and academic medicine in order to determine if antituberculous agent selection differed between these two groups. The majority of the 109 physicians who responded to the questionnaire (64.2%) indicated that they would use isoniazid, rifampin, and a third agent. There was no statistical difference in the choice of ethambutol, pyrazinamide, or streptomycin as the third drug. There was no difference between university and community based physicians in the use of three drug combinations or in the selection of the specific third agent. This study suggests that, although the majority of pulmonologists responding would treat the patient with respiratory insufficiency from tuberculosis with an aggressive three drug approach, there is no consensus as to which agent should be the third drug.

Antitubercular Agents↗
PubMed1990

The forensic science implications of site and temporal influences on postmortem blood-drug concentrations.

The dependence of postmortem blood-drug concentrations on the collection site and on the postmortem interval before specimen collection has been studied. These studies consisted of both sequential sampling from the same collection site at defined time intervals and a comparison of the drug concentrations of postmortem blood simultaneously collected from various sites. A site and time dependence was observed for postmortem blood-drug concentrations. The heart blood-drug concentrations were, in general, significantly higher than those of peripheral specimens. As a result of this phenomenon, the analysis of peripheral blood specimens and solid tissues is often necessary before a definitive interpretation of postmortem toxicological analyses is possible.

Absorption↗
PubMed1989

AIDS in Cuba.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Tularemic pneumonia mimicking Legionnaires' disease with false-positive direct fluorescent antibody stains for Legionella.

Pleuropulmonary tularemia may mimic atypical pneumonia caused by other common etiologic agents, including Legionella. The correct identification of the pathogen responsible for the atypical pneumonia is usually made serologically or with the use of special stains and cultures. We have reported a case of pleuropulmonary tularemia whose diagnosis was confounded by false-positive direct fluorescent antibody stains for Legionella.

Adult↗
PubMed1989

Image data compression in magnification hand radiographs.

A study was conducted on the use of an irreversible compression technique, Fourier quantization, to reduce the amount of digital data needed for an image. The effect of image compression was studied in radiographs obtained to diagnose subperiosteal bone resorption. Magnification radiographs of 44 hands were digitized to an array size of 4,096 X 4,096 X 12 bits. Selected subregions containing a single middle phalanx were compressed and reconstructed. A subset of the resultant 12-bit uncompressed and 8-, 7-, and 6-bit compressed images were read by four radiologists whose responses were analyzed with receiver operating characteristic (ROC) techniques. There were 81 images used in the ROC analysis, of which 48 were normal and 33 showed subperiosteal resorption. No statistically significant loss of diagnostic quality was detected for 8- or 7-bit compressed images, with average compression ratios of 16:1 and 28:1, respectively. Diagnostic quality was lost with 6-bit images, with an average compression ratio of 107:1.

Arthritis↗
PubMed1989

Resting gas exchange in nonsmoking bituminous-coal miners with simple pneumoconiosis.

Gas exchange at rest under normoxic conditions was studied in 2,297 nonsmoking bituminous-coal miners with and without simple coal workers' pneumoconiosis (CWP). Measurements of arterial oxygen tension (Pao2) and arterial carbon dioxide tension (Paco2) from blood gas samples obtained at rest in the seated position were used to calculate the alveolar-arterial oxygen tension difference, (A-a)Do2, using the classic alveolar-air equation. We then recalculated the (A-a)Do2 using the age-predicted Pao2 for each miner. The difference between the actual and the predicted (A-a)Do2 was measured and the mean difference for each category of simple CWP was analyzed. We found no evidence that the resting gas exchange differs significantly from the age-predicted (A-a)Do2 in the nonsmoking bituminous-coal minor with simple CWP. Likewise, there is no significant change in (A-a)Do2 with change in the category of simple CWP.

Age Factors↗
PubMed1989

Pulmonary complications after tricyclic antidepressant overdose.

We studied 82 consecutive patients admitted to the ICU with predominant tricyclic antidepressant overdose (mean plasma tricyclic level, 1,025 ng/ml) to determine the nature and incidence of respiratory complications. The majority of patients (80.4 percent) had a decreased arterial to alveolar oxygen tension ratio (PaO2/PAO2) on initial emergency room arterial blood gas analysis (mean, 0.56). Mechanical ventilation was required in 76.8 percent of the patients for a mean duration of 46.2 h. Chest radiograph abnormalities developed during the first 48 h in 32/82 patients (39 percent). The group with radiographic abnormalities had higher mean drug levels than the group without (p less than 0.05). Of 82 patients, nine (11 percent) developed radiographic evidence of bilateral alveolar infiltrates suggestive of acute lung injury. This group had significantly higher mean drug levels than the groups with other types of radiographic abnormalities (p less than 0.001). Charcoal was recovered from the airway of 18/72 patients who received activated charcoal slurry by nasogastric tube in the emergency room after endotracheal intubation. The group who aspirated did not show statistically significant difference in the incidence of chest radiograph abnormalities, gas exchange, or survival compared with the group that did not aspirate.

Adult↗