Search PubMed⌕ Search

Biomedical subjects

D W White

Publications and source records attributed to D W White.

71 records · Page 4Linked to original sources
PubMed1981

Death certificate study of leukemia among farmers from Wisconsin.

The risk of leukemia among farmers and dairy farmers in particular was studied with the use of mortality records from Wisconsin, 1968-76. A comparison of occupation as noted on the death certificate for 1,499 cases and a like number of matched controls revealed a slight [odds ratio (OR) = 1.10], but statistically nonsignificant, excess risk of leukemia among farmers. The risk was highest among those born after 1897 (OR approximately 1.50) or dying before age 71 years (OR approximately 1.35) among dairy farmers (whether noted on death certificates or identified by county agricultural agents of the Cooperative Extension Programs of the University of Wisconsin) and all farmers alike. The under-representation of farmers among controls with smoking-related causes of death, however, may partially account for these findings. Stratification by county of residence showed significantly elevated risks among farmers from counties with heavy dairy production (OR = 1.40) and fertilizer use (OR = 1.42).

Age Factors↗
PubMed1981

Antimicrobial activity and synergism of cefuroxime on anaerobic bacteria.

In vitro efficacy of cefuroxime was tested against 333 clinical isolates of anaerobic bacteria, including 80 strains of Bacteroides fragilis. Its activity was compared with that of cefamandole and cefoxitin. In addition, the antimicrobial synergism of cefuroxime was tested in combination with either penicillin or carbenicillin against B. fragilis. At 16 microgram/ml, cefuroxime inhibited 70% of all anaerobic bacteria, but it was ineffective against 64% of B. fragilis strains tested. Cefuroxime in combination with penicillin or carbenicillin exerted excellent synergistic activity against two of the three isolates of B. fragilis tested and had an additive effect on the other. Although cefuroxime by itself is ineffective against B. fragilis, it acts synergistically with penicillin or carbenicillin.

Anaerobiosis↗
PubMed1981

Substance P in the central nervous system.

A radioimmunoassay has been developed for measuring substance P-like immunoreactivity. Assay sensitivity was 0.7fmoles of substance P. Using the radioimmunoassay substance P-like immunoreactivity was detected in postmortem tissue samples from the central nervous system of rats and humans. Immunofluorescence studies confirmed the localisation of substance P in the dorsal horn of the spinal cord.

Animals↗
PubMed1979

Retinoblastoma Y79 cell line: a study of membrane structures.

The continuous retinoblastoma cell line Y79, grown in suspension culture, has been examined by transmission and scanning electron microscopy, including freeze-fracture replica preparations. Four classes of cells were distinguishable by their size and surface characteristics. The surface structures included blebs, filopodia, lamellipodia, microvilli, and microplicae. The possible origin of a most unusual type of cell, apparently forming natural clones, is discussed.

Cell Line↗
PubMed1978

Lymphocyte cytotoxicity in the X-irradiation induced rat small bowel adenocarcinoma. II. Presence of cytotoxic lymphocytes in irradiated animals.

Cytotoxic peripheral blood lymphoid cells were demonstrated in both Holtzman and Lewis Brown-Norway rats which had received 2000R of local X-irradiation to the temporarily hypoxic, exteriorized, ileum and jejunum regardless of whether a small bowel adenocarcinoma subsequently developed. The cytotoxic response, which was detectable at two days, was quite evident by day 5 post-irradiation. No evidence of cross-reacting tumor antigens was obtained when similarly processed effector cells from Holtzman rats bearing a spontaneous mammary carcinoma were incubated with cell cultures derived from the small bowel adenocarcinoma. These findings indicate X-irradiation of the small bowel initiates lymphocyte sensitization that is manifested as in vitro cytotoxicity against cell cultures of the adenocarcinoma.

Adenocarcinoma↗
PubMed1977

Lymphocyte cytotoxicity in X-irradiation-induced adenocarcinoma of the rat small bowel. I. Measurement of target cell destruction by release of radioiodinated membrane proteins: brief communication.

A cell-mediated immune response as denoted by lymphocyte cytotoxicity was detected in Holtzman rats with X-irradiation-induced adenocarcinomas of the small bowel. Cytotoxicity was measured by target cell destruction as determined by release of intracellular 51Cr or radioiodinated (125I) membrane proteins. The radioiodination assay possessed an important advantage over the 51Cr technique in that the radiolabel was spontaneously lost slowly, thus permitting long-term studies.

Adenocarcinoma↗
PubMed1977

Torsion of the wandering spleen seen as a migratory abdominal mass.

Torsion of the wandering spleen is an unusual cause of an acute abdomen, rarely diagnosed preoperatively. The authors describe a case which was suspected prior to surgery and confirmed by radionuclide imaging. Radiographic findings include an extrinsic mass on barium-enema examination and absence of the splenic shadow in the left upper quadrant.

Adult↗
PubMedDate not supplied

CD8+ T cells in intracellular bacterial infections of mice.

In the normal course of an immune response, both CD4+ and CD8+ T cells respond to each of the bacterial pathogens we have discussed and both responses may be required for the most potent immunity to infection. In this discussion, we have focused on the ability of these organisms to prime CD8+ T-cell responses in vivo and the ability of CD8+ T cells as sole mediators of acquired immunity, to protect against infection. It is clear that the vacuolar location of bacterial pathogens such as Salmonella or Mycobacteria does not prevent in vivo priming of CD8+ T-cell responses to these pathogens. However, vacuolar localization may affect the potency of CD8+ T-cell responses under experimental conditions that assess the capacity of CD8+ T cells as the sole mediators of acquired immunity. In the case of cytoplasmic L. monocytogenes, clear evidence exists that antigen-specific CD8+ T cells, in the absence of immune CD4+ T cells, can provide substantial acquired immunity to naive mice. Similar clear experimental results with Salmonella and Mycobacteria are lacking. Such results would provide stronger support for vaccines that elicit CD8+ T-cell responses to these vacuolar pathogens. Although our discussion has focused on only three specific organisms, we suggest that detection of an in vivo CD8+ T-cell response to a bacterial antigen does not ensure that the response will be protective against infection in a vaccine setting. In the case of Salmonella and Mycobacteria, this issue remains unresolved.

Animals↗
PubMedDate not supplied

Causes of death among workers in the tobacco industry.

The number of deaths by cause, race, and sex among 2,709 workers (1,003 white males, 789 black males, 517 white females, and 400 black females) in the tobacco industry identified from obituary listings of the Tobacco Workers' International Union from 1957 to 1978 were compared to expected numbers based on the experience of the U.S. population. The frequency of deaths from cancer of the colon was slightly elevated among each race-sex group [proportionate mortality ratios (PMRs) from 129 to 163]. Although unexplained, this resembles the excess of cancer of the digestive system previously reported among cigarette manufacturers. The excess deaths from cancer of the lung occurred only among white females and may represent chance findings. Among non-neoplastic causes of death, PMRs for arteriosclerotic heart disease, motor vehicle accidents, and suicides were high among most race-sex groups, while PMRs for respiratory disease and cirrhosis of the liver were low.

Adult↗
PubMedDate not supplied

Leukemia cell types and agricultural practices in Nebraska.

The risk of specific histologic types of leukemia among farmers was investigated using mortality records from Nebraska for the years 1957-1974. The frequency of farming as an occupation listed on the death certificates among 1,084 leukemia deaths was compared to the corresponding frequency for 2,168 controls for calculation of odds ratios (OR). The elevated OR for chronic lymphatic leukemia among farmers was statistically significant (OR = 1.67), while elevated ORs for acute lymphatic leukemia (OR = 1.34), acute monocytic leukemia (OR = 1.94), and acute unspecified leukemia (OR = 2.36) were not. Farmers who died at younger ages or who were born in more recent years were at greater risk of acute lymphatic, acute myeloid, chronic myeloid, acute unspecified, and unspecified leukemia than other farmers. Certain cell types were related to agricultural characteristics of the subject's county of residence, although few were statistically significant. Farmers from counties with large cattle inventories and significant dairy activity were at higher risk of chronic lymphatic leukemia. Farmers from major corn-producing, hog- and chicken-raising, and pesticide- and fertilizer-using counties tended to be at higher risk of acute lymphatic, acute myeloid, chronic myeloid, and acute unspecified leukemia than farmers from counties less involved in the production or use of these agricultural factors.

Adult↗