Biomedical subjects

D J Hurley

Publications and source records attributed to D J Hurley.

9 recordsLinked to original sources

PubMed1991

Numbers and percent of T lymphocytes in bovine peripheral blood during the periparturient period.

To determine if periparturient immunosuppression in dairy cattle might be due to an alteration in total numbers of percent of T lymphocytes, we examined the numbers and percent of T lymphocyte subsets in peripheral blood from periparturient dairy cows, some of which received recombinant bovine granulocyte colony stimulating factor (rbG-CSF) during the study. Beginning 2 weeks preparatum through 4 weeks postpartum, peripheral blood mononuclear cells (PBMC) were collected and labeled with monoclonal antibodies to BoCD5, BoCD4, and BoCD8, and the percent of cells positive for each marker measured by flow cytometry. The percent of PBMC expressing BoCD5 (total T cells), and BoCD8 (T suppressor/cytotoxic cells) was not significantly different between the groups, or at different times before and after calving. The percent of PBMC expressing BoCD4 (T helper cells) was not significantly different between the groups, however, within both groups there was a higher percent of BoCD4+ cells after calving than during the prepartum period. In cows receiving rbG-CSF, total numbers of PBMC were significantly increased compared to controls during the postpartum treatment period.

Animals↗

PubMed1990

Culture conditions for blastogenic responses of bovine mammary mononuclear cells.

Several experimental parameters were examined to determine optimal conditions for proliferative responses of mammary mononuclear cells (MMC) obtained from six nonlactating dairy cows. These parameters were: pre-incubation of cells in medium prior to assay, mitogen concentration, assay incubation time, and type of culture medium. Response variables included viability of cells and the rate of proliferation as assessed by tritiated thymidine incorporation. Pre-incubation of cells in medium had no effect on the proliferative response of MMC. Whereas Concanavalin A (ConA; 3.3 or 6.6 micrograms/ml) and phytohemagglutinin (PHA; 1, 5, 10 micrograms/ml) did stimulate proliferation of MMC, the higher doses did not stimulate greater proliferation than the lower doses of mitogens. The greatest mitogenic response was obtained on days 2 and 3 of incubation. Proliferative responses were significantly higher at all mitogen levels tested in a 50-50 mixture of Rosewell Park Memorial Institute medium 1640 and Liebovitz-15 medium (RPMI/L-15) than in RPMI alone. Viability of MMC was also significantly higher in the RPMI/L-15 medium. To test whether the significant effect of media on blastogenesis was specific for mononuclear cells from the bovine mammary gland, peripheral blood lymphocytes (PBL) from four dairy cows were cultured with ConA and PHA in a mitogen assay in both RPMI and RPMI/L-15. Viability was measured on day of collection and on all culture days. PBL were stimulated equally in both media. PBL viability decreased significantly on day 1 in both RPMI and RPMI/L-15. These results suggest that the optimal culture conditions for blastogenic responses of mammary mononuclear cells and peripheral blood lymphocytes may differ.

Animals↗

PubMed1990

An evaluation of the mononuclear cells derived from bovine mammary gland dry secretions using leukocyte antigen specific monoclonal antibodies, light scattering properties and non-specific esterase staining.

The distribution of mononuclear cells isolated from the bovine mammary gland during the nonlactating (dry) period was examined using monoclonal antibodies against leukocyte cell surface antigens, cellular light scattering properties, and the presence of nonspecific esterase. Most of the mononuclear cells isolated during the dry period were lymphocytes. T cells predominated until about 1 week prior to parturition. During the week prior to calving, the percentage of B cells increased until it approximated T cells. The ratio of CD4:CD8 cells was 2-3:1 for mammary gland T cells. This was similar to the ratio found in peripheral blood. At dry-off, about 12% of mammary mononuclear cells were macrophages. The macrophage percentage increased (to about 30%) at mid-dry and remained at this levels until parturition. PMN's were isolated with the mononuclear cells during the first 2 weeks dry and the week prior to calving. Three methods were used to identify mammary macrophages. Esterase staining (as an enzymatic method), forward angle/90 degrees light scatter (based on size and internal complexity), and MHC class II/forward angle light scatter (based on size and surface markers) were compared. Each method yielded similar specificity for macrophage identification. Non-adherent cell fractions, obtained by passage of the cells over Sephadex G-10 columns, were enriched in CD4 positive T cells, somewhat depleted of B cells, and depleted of macrophages and PMN's. Cells eluted from G-10 columns, with lidocaine, were mostly lymphocytes, but reflected the cells loaded onto the column.

Animals↗

PubMed1990

Children's observations of violence: I. Critical issues in child development and intervention planning.

Children are often the unintended or indirect victims of wife abuse as witnesses of this violence in their family. Current research on these children and a conceptual framework to understand how this violence affects their development are outlined. The implications of this research are discussed in terms of several intervention strategies. The importance of primary prevention programs in school systems is stressed.

Canada↗

PubMed1990

Children's observations of violence: II. Clinical implications for children's mental health professionals.

This paper discusses the clinical implications of our current knowledge about children exposed to violence. It highlights a number of typical case scenarios in which mental health professionals have responded inadequately to the issue of violence. Alternative strategies for assessing and treating children exposed to violence are offered which have both therapeutic and preventative value. Finally, a family based assessment and treatment approach, which may be appropriate in a number of cases, is suggested.

Child↗

PubMed1987

Differentiation of peanut lectin positive suppressor T-cells from peanut lectin negative precursors in bovine cells by 12-O-tetradecanoylphorbol-13-acetate.

Although 12-O-tetradecanoylphorbol-13-acetate (TPA) can synergize with lectins to enhance lymphocyte proliferation, pretreatment of lymphocytes with TPA decreases their response. Pretreatment also inhibits the response to allogeneic cells in the mixed lymphocyte culture. In this study we determined that at least part of this inhibition was due to the generation of T-lymphocytes with the ability to suppress proliferation in vitro. By using populations enriched in lymphocytes or macrophages we determined that the interaction of TPA with lymphocytes, but not macrophages, was required to mediate the suppression. The number of macrophages present in culture (range, 0.5-10%) was irrelevant to the generation of inhibitory activity. Moreover, the TPA-induced suppressor activity copurified with T-cells. Furthermore, when peanut lectin (agglutinin) (PNA) was used to separate T-cells after treatment with TPA, essentially all of the activity copurified with the PNA positive cells. When PNA separations were carried out before treatment with TPA, the suppressor activity arose from the PNA negative fraction. Therefore, TPA appeared to cause phenotypically PNA negative T-cells to gain the PNA positive marker, as well as to function as suppressor cells in vitro. Suppressor activity was also found in the culture medium. Thus the suppression observed may be mediated through a soluble factor released by the TPA-treated cells. Although the suppressor cell activity induced by TPA can only partially account for its in vitro inhibition of lymphocyte proliferation, the development of suppressor cells merits further study with respect to lymphocyte phenotypic and functional differentiation. The results also suggest the possibility that similar processes could occur in vivo, possibly during the course of tumor promotion.

Animals↗

PubMed1987

Induction of suppressor activity by tumor-promoting phorbol esters in primary cultures of lymph node cells.

We have observed the induction of suppressor activity in primary cultures of lymphocytes by the tumor-promoting phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA). Suppressor activity was detected as the ability of TPA-treated lymphocytes to inhibit proliferation in mixed lymphocyte cultures (MLC). Induction of this activity was dependent on the dose of TPA and was maximal after approximately 12 h of incubation. Neither the induction of the activity, nor the activity itself was inhibited by indomethacin or interleukin 2 (IL2). A comparison of addition of TPA directly to the MLC, addition of TPA pretreated cells as participants in the MLC and addition of cells treated with TPA to induce suppressor activity suggested that the suppressor activity was only one of the ways that TPA could inhibit proliferation. This suppressor activity may account for some of the reported effects of TPA in immunological systems in vitro and suggests that suppressor cells could play a role in TPA-mediated promotion in vivo.

Animals↗

PubMed1979

Human lymphocyte-tumor cell interaction. A scanning electron microscopy study.

Cells from the metastatic chest wall lesions of a patient with adenocarcinoma of the breast were incubated with autologous lymphocytes. Their interactions were observed in the scanning electron microscope. The lymphocytes first surrounded the cancer cells; cancer cells then were destroyed while the lymphocytes in contact with them lost their microvilli. The heterologous human lymphocytes being used as controls surrounded the tumor cells but did not destroy them. Lymphocytes in the presence of tumor cells showed interconnections through cytoplasmic bridging.

Adenocarcinoma↗

PubMed1979

Morphologic expression of the interactions of human lymphocytes and Pseudomonas aeruginosa as observed by scanning electron microscopy.

When human lymphocytes and Pseudomonas aeruginosa were incubated together and then observed under the scanning electron microscope, four distinct morphologic observations were made: (1) filopods extending between lymphocytes and bacteria; (2) globular structures bulging out in many of the filopods; (3) filopods connecting lymphocytes to each other in the presence of bacteria; and (4) bacteria adhering to the lymphocytes in areas where decreased numbers of microvilli were present.

Adult↗