Effects of injected leukemia inhibitory factor on hematopoietic and other tissues in mice

Purified bacterially synthesized recombinant murine leukemia inhibitory factor (LIF) was injected in varying doses for up to 2 weeks into adult DBA/2 and C3H/HeJ mice. At high doses (2 micrograms, three times daily) LIF exhibited toxic effects seen as behavioral changes, loss of body fat, and thymus atrophy. Dose-related rises were observed in blood platelets, erythrocyte sedimentation rates, and serum calcium to albumin ratios, including dose schedules with no toxic effects. LIF induced a decrease in bone marrow cell numbers, particularly in marrow lymphocytes, and a moderate increase in spleen weight with a reduction in spleen lymphocytes and an elevation of erythroid populations. LIF-injected mice showed a rise in megakaryocytes up to twofold in the marrow and fivefold in the spleen, with an associated 10-fold rise in megakaryocyte progenitor cells in the spleen. Comparable rises in other types of progenitor cells were also observed in the spleen. The observed changes indicate the biologic activity of LIF in vivo and are consistent with the known wide range of in vitro actions of this molecule. The ability of LIF to elevate megakaryocyte and platelet levels suggests a potential clinical application of LIF in the treatment of thrombocytopenias.     

Developing a behavioral model for mobile phone-based diabetes interventions

Objectives

Behavioral models for mobile phone-based diabetes interventions are lacking. This study explores the potential mechanisms by which a text message-based diabetes program affected self-management among African-Americans.

Methods

We conducted in-depth, individual interviews among 18 African-American patients with type 2 diabetes who completed a 4-week text message-based diabetes program. Each interview was audio-taped, transcribed verbatim, and imported into Atlas.ti software. Coding was done iteratively. Emergent themes were mapped onto existing behavioral constructs and then used to develop a novel behavioral model for mobile phone-based diabetes self-management programs.

Results

The effects of the text message-based program went beyond automated reminders. The constant, daily communications reduced denial of diabetes and reinforced the importance of self-management (Rosenstock Health Belief Model). Responding positively to questions about self-management increased mastery experience (Bandura Self-Efficacy). Most surprisingly, participants perceived the automated program as a “friend” and “support group” that monitored and supported their self-management behaviors (Barrera Social Support).

Conclusions

A mobile phone-based diabetes program affected self-management through multiple behavioral constructs including health beliefs, self-efficacy, and social support.

Practice implications

Disease management programs that utilize mobile technologies should be designed to leverage existing models of behavior change and can address barriers to self-management associated with health disparities.     

UHMWPE Wear Debris and Tissue Reactions Are Reduced for Contemporary Designs of Lumbar Total Disc Replacements

Background

Lumbar total disc replacement (L-TDR) is a procedure used to relieve back pain and maintain mobility. Contemporary metal-on-polyethylene (MoP) L-TDRs were developed to address wear performance concerns about historical designs, but wear debris generation and periprosthetic tissue reactions for these newer implants have not been determined.

Questions/purposes

The purpose of this study was to determine (1) whether periprosthetic ultrahigh-molecular-weight polyethylene (UHMWPE) wear debris and biological responses were present in tissues from revised contemporary MoP L-TDRs that contain conventional cores fabricated from γ-inert-sterilized UHMWPE; (2) how fixed- versus mobile-bearing design affected UHMWPE wear particle number, shape, and size; and (3) how these wear particle characteristics compare with historical MoP L-TDRs that contain cores fabricated from γ-air-sterilized UHMWPE.

Methods

We evaluated periprosthetic tissues from 11 patients who received eight fixed-bearing ProDisc-L and four mobile-bearing CHARITÉ contemporary L-TDRs with a mean implantation time of 4.1 and 2.7 years, respectively. Histologic analysis of tissues was performed to assess biological responses and polarized light microscopy was used to quantify number and size/shape characteristics of UHMWPE wear particles from the fixed- and mobile-bearing devices. Comparisons were made to previously reported particle data for historical L-TDRs.

Results

Five of seven (71%) fixed-bearing and one of four mobile-bearing L-TDR patient tissues contained at least 4 particles/mm² wear with associated macrophage infiltration. Tissues with wear debris were highly vascularized, whereas those without debris were more necrotic. Given the samples available, the tissue around mobile-bearing L-TDR was observed to contain 87% more, 11% rounder, and 11% less-elongated wear debris compared with tissues around fixed-bearing devices; however, there were no significant differences. Compared with historical L-TDRs, UHMWPE particle number and circularity for contemporary L-TDRs were 99% less (p = 0.003) and 50% rounder (p = 0.003).

Conclusions

In this preliminary study, short-term results suggest there was no significant influence of fixed- or mobile-bearing designs on wear particle characteristics of contemporary L-TDRs, but conventional UHMWPE has notably improved the wear resistance of these devices compared with historical UHMWPE.     

Feminist identity,body image,and disordered eating

ABSTRACT

Using data from a community-based sample (Project EAT-III), this study (N = 1241; mean age = 25.2) examined the relationship of feminist identity with body image and disordered eating. Feminist-identified women reported significantly higher body satisfaction than non-feminist women and women who did not identify as feminists but held feminist beliefs. However, feminist-identified women did not differ from non-feminist women in disordered eating. Women holding feminist beliefs and non-feminist women did not differ in body satisfaction. Our findings suggest that self-identification as a feminist may promote positive body image in young adult women, but may be insufficient to change behaviors.     

Reaping benefits from intellectual capital

The wealth and value of organizations are increasingly based on intellectual capital. Although acquiring talented individuals and investing in employee learning adds value to the organization, reaping the benefits of intellectual capital involves translating the wisdom of employees into reusable and sustained actions. This requires a culture that creates employee commitment, encourages learning, fosters sharing, and involves employees in decision making. An infrastructure to recognize and embed promising and best practices through social networks, evidence-based practice, customization of innovations, and use of information technology results in increased productivity, stronger financial performance, better patient outcomes, and greater employee and customer satisfaction.