Functional characterization of a stable, noncytolytic stage of macrophage activation in tumors

The state in which macrophages (Mphi) from regressing Moloney sarcomas could kill tumor target cells was a highly labile one which decayed rapidly in vitro. Thereafter, regressor Mphi were noncytolytic. Mphi from several different progressing sarcomas failed to kill, even when challenged with target cells immediately after explantation. Similarly, thioglycollate-induced peritoneal Mphi (TG-Mphi) did not kill. Noncytolygic Mphi derived either from progressing sarcomas or from long-term (up to 96 h) cultures of regressor Mphi were exquisitely sensitive to stimulation by bacterial lipopolysaccharide (LPS); picogram/milliliter amounts induced killing. Similar concentrations of LPS had no demonstrable effect on TG-Mphi. Thus, tumor Mphi generally appeared to have been primed in vivo, with those in regressing sarcomas having additionally acquired cytolytic activity. Inability of progressor Mphi to kill apparently stemmed from lack of, or failure to respond to, the signal needed in vivo to trigger cytolytic activity, rather than the total absence of activation.     

Treatment of Acid Leachate from Coal Discard using Calcium Carbonate and Biological Sulphate Removal

Abstract.   An integrated approach is proposed for treating acidic coal discard leachate, consisting of CaCO₃ handling and dosing, CaCO₃-neutralization, and biological sulphate removal. It was found that: powdered CaCO₃ can be slurried to a constant density and used to neutralize the acid water, remove Fe (II), Fe (III), and Al, and partially remove the sulphate (to saturation level); biological sulphate removal can be used to lower the sulphate to less than 200 mg/L using ethanol as the carbon and energy source; CO₂ produced during calcium carbonate treatment can be used for H₂S-stripping and; H₂S gas recovered in the sulphate removal stage can be used for iron removal.     

Induction of T-cell hyporesponsiveness by intrahepatic modulation of donor antigen-presenting cells

In this study, we examined the ability of varying populations of donor cells from B6 mice to induce hyporesponsiveness in T lymphocytes from C3H mice in vitro and in vivo. Small, resting B lymphocytes were inefficient stimulators of T-lymphocyte proliferation compared to splenic mononuclear cells (SMNC) and lipopolysaccharide (LPS)-induced B-cell blasts in vitro (P < 0.05). Pretreatment of SMNC with anti-B7-1 or anti-intracellular adhesion molecule-1 (ICAM-1) monoclonal antibodies (mAb) similarly resulted in inefficient stimulation of T-cell proliferation in vitro (P < 0.05). However, in vivo, only intrahepatic, but not intravenous, injection of donor cells into C3H mice resulted in decreased T-lymphocyte proliferation in response to restimulation by alloantigen. This effect was most pronounced following intrahepatic injection of resting B lymphocytes or SMNC pretreated with anti-ICAM-1 mAb compared to uninjected or intravenously injected mice (P < 0.05). The hyporesponsiveness was associated with an increased production of interleukin-4 (IL-4) by the responder T lymphocytes and correlated with enhanced skin allograft survival. These data demonstrate that intrahepatic injection of donor-derived cells induces T-lymphocyte hyporesponsiveness. The mechanism appears to be modulated by an ICAM-1-mediated signal resulting in expansion of an IL-4-producing T-lymphocyte population.     

Apoptosis as a cause of death in measles virus-infected cells

To determine the mechanism of measles virus-induced cell death, we studied the infection of Vero cells and monocytic cell lines with wild-type (Chicago-1) and vaccine (Edmonston) strains of measles virus. DNA fragmentation indicative of apoptosis was apparent by flow cytometry, agarose gel electrophoresis, and electron microscopy. Within syncytia, DNA strand breaks were demonstrated by end labeling with terminal transferase and then by visualization.     

Arthroscopic-assisted reduction of distal radius fractures

The outcomes of seven patients with severe comminuted intraarticular fractures of the distal radius treated by arthroscopic reduction and percutaneous external fixation (ARPEF) were retrospectively reviewed. All of the fractures were classified as C3 types using the AO classification scheme. Outcomes were evaluated using the Gartland and Werley functional criteria, an objective wrist examination, a radiographic analysis, and a self-assessment outcome form at an average follow-up of 27 months (range, 12 to 45 months). All patients were free of pain and had returned to their prior occupations. No patient had articular incongruency of greater than 1 mm, and there was no evidence of radiocarpal degenerative change. Active range of motion and maximal grip strength averaged 92% and 98%, respectively, of the uninjured wrist. The technique of arthroscope-assisted reduction and percutaneous external fixation yielded excellent results in a small group of patients, with minimal complications.     

Transference in social perception: the role of chronic accessibility in significant-other representations

Research has shown that the activation and application of a significant-other representation to a new person, or transference, occurs in everyday social perception (S. M. Andersen & A. Baum, 1994; S. M. Andersen & S. W. Cole, 1990). Using a combined idiographic and nomothetic experimental paradigm, two studies examined the role of chronic accessibility of significant-other representations in transference. After learning about 4 fictional people, 1 of whom resembled a significant other, participants' recognition memory was assessed. Both studies showed greater false-positive memory in the significant-other condition, relative to control, even in the absence of priming. Study 2 showed that although the effect was greater when the significant-other representation was concretely applicable to the target information, it occurred even when no such applicability was present. Results implicate the chronic accessibility of significant-other representations in transference.