Minichromosomes assembled on the mouse mammary tumor virus (MMTV) promoter in vitro exhibit positioned nucleosomes, one of which covers the binding sites for progesterone receptor (PR) and nuclear factor 1 (NF1). Incorporation of histone H1 into MMTV minichromosomes improves the stability of this nucleosome and decreases basal transcription from the MMTV promoter, as well as its response to eit...

The effects of in vitro pretreatment with benzene metabolites on colony-forming response of murine bone marrow cells stimulated with recombinant granulocyte/macrophage colony-stimulating factor (rGM-CSF) were examined. Pretreatment with hydroquinone (HQ) at concentrations ranging from picomolar to micromolar for 30 min resulted in a 1.5- to 4.6-fold enhancement in colonies formed in response to...

Rosettes against SRBC were made from normal spleen cells. Although T rosettes tend to dissociate, they could be stabilized with 0.05% sodium azide. A clear separation of nonrosettes, T rosettes, and B rosettes was obtained by subjecting the suspension of splenic rosettes to velocity sedimentation at unit gravity. Each fraction was injected with either normal bone marrow cells or normal thymus c...

Earlier workers suggested that synergism of polymyxin and sulfonamides occurred because sulfonamides produced changes in the cell wall which permitted the more ready access of polymyxin. We tested this hypothesis by using L-forms, which lack cell wall. The demonstration that synergism of polymyxin and sulfonamides occurs in L-forms of Proteus mirabilis and Staphylococcus aureus suggested that t...

RESEARCH BACKGROUND Currently, multiple myeloma is the second most common hematological malignancy in the U.S., constituting 1% of all cancers. With conventional treatment, the median survival time is typically 3-4 years, although it can be extended to 5-7 years or longer with advanced treatments. Recent research indicated that an increase in osteoclast (OC) activity is often associated withmul...

polybrominated diphenyl ethers (pbdes) have been widely used in many products as flameretardants, which resulted in their release into the environment. little is known about the impact of coexisting pbdes on organisms. in this study, the in vivo effects of bde-47 and bde-99 on a suite of biomarkers, acetyl cholinesterase (ache), ethoxyresorufin-o-deethylase (erod), glutathione-s-transferase (gs...

The genes for the hemopoietic growth factors, GM colony-stimulating factor (CSF) and G-CSF have been cloned, and recombinant material is available for both. We tested these recombinant factors for their effects on the blast cells of acute myeloblastic leukemia (AML). Culture methods are available that support both colony formation by AML blasts and the growth of blast stem cells in suspension. ...

Background: Hemostasis in human body depends on a complicated series of events which actively involve blood platelets. Platelets exhibit diverse responses in a variety of agonists. In vivo, most of the agonists act in synergism, causing aggregation of platelets. Methods: The synergism between ADP – Epinephrine and Epinephrine – Collagen has been determined in this study by means of turbidometri...

An experiment was designed to determine the effect of radiation dosage on the synergism between radiation and estrogen in the production of mammary cancer. Female A x C rats had their left mammary chain exposed to graded doses of X-radiation while under anesthetic with urethan or sodium pentobarbital. The rats had previously been hysterectomized and exposed to estrogen by implantation with chol...

The concentration addition (CA) and the independent action (IA) models are widely used for predicting mixture toxicity based on its composition and individual component dose-response profiles. However, the prediction based on these models may be inaccurate due to interaction among mixture components. In this work, the nature and prevalence of non-additive effects were explored for binary, terna...