Exploitation of the intestinal microflora by the parasitic nematode Trichuris muris.

The inhabitants of the mammalian gut are not always relatively benign commensal bacteria but may also include larger and more parasitic organisms, such as worms and protozoa. At some level, all these organisms are capable of interacting with each other. We found that successful establishment of the chronically infecting parasitic nematode Trichuris muris in the large intestine of mice is dependent on microflora and coincident with modulation of the host immune response. By reducing the number of bacteria in the host animal, we significantly reduced the number of hatched T. muris eggs. Critical interactions between bacteria (microflora) and parasites (macrofauna) introduced a new dynamic to the intestinal niche, which has fundamental implications for our current concepts of intestinal homeostasis and regulation of immunity.

The role of TNF-alpha in Trichuris muris infection I: influence of TNF-alpha receptor usage, gender and IL-13.

Th1 and Th2 responses to the gut-dwelling nematode Trichuris muris have been well established in mouse models of infection, with Th2 responses clearly playing an important role in resistance. TNF-alpha has previously been shown to play an undefined role in resistance, although it is not a typical Th2 cytokine. However, the relative importance of the two TNF-alpha receptors, p55 and p75, has not previously been investigated. We demonstrate that p55 is the dominant TNF-alpha receptor during T. muris infection as p55-/- mice are more susceptible to infection than p75-/- mice. Moreover, p75 clearly plays a role in negatively regulating TNF-alpha. We also demonstrate that a gender difference influences the immune response of p55-/- and p75-/- mice in response to T. muris infection, with female mice fully expelling by day 35 post-infection (p.i.) and male mice harbouring chronic infections. Further, this gender difference can be reversed with recombinant IL-13 (rIL-13) in male gene-deficient mice or IL-13R2.Fc treatment in female gene-deficient mice.

The role of TNF-alpha in Trichuris muris infection II: global enhancement of ongoing Th1 or Th2 responses.

Host resistance to Trichuris muris is driven by Th2 responses. However, TNF-alpha has also been shown to play a role in protection. As TNF-alpha has a variety of actions, the exact role of TNF-alpha in immunity to T. muris is yet to be established. Here we demonstrate that although blocking TNF-alpha has been shown to abrogate resistance, rTNF-alpha treatment does not promote resistance. Further, we show that TNF-alpha functions to enhance the ongoing immune response. AKR animals that typically respond to infection with a polarized Th1 response produce greater levels of Th1 cytokines when treated with TNF-alpha and BALB/c animals that normally respond with a polarized Th2 response produce higher levels of Th2 cytokines. Crucially, blocking TNF-alpha in the strong Th2 responder strain BALB/c does not prevent expulsion of T. muris, thus supporting its role as a biological enhancer. TNF-alpha does increase transcription of both IFN-gamma and IL-13 in vitro but can also act synergistically with IL-13 in vitro to promote production of RELMbeta, which has also been shown to play a role in resistance to T. muris. Thus, this data demonstrates that TNF-alpha acts to enhance an ongoing immune response but is not necessary for a strong protective Th2 response.

Literacy for health information of adult patients and caregivers in a rural emergency department.

The nurse practitioner is responsible for providing the patient and family with understandable written information before discharge from the emergency department (ED) following an acute event. Patients are more likely to adhere to their treatment regimen and follow-up if they have a clear understanding of their instructions. Patients cannot correctly interpret information they cannot read. This study describes the ability of two age groups of rural ED patients or caregivers to read health information. The literacy level of 91 younger adults and 104 elderly adults from three rural hospitals was assessed at discharge with the Rapid Estimate of Adult Literacy in Medicine (REALM). While there was no difference in the REALM scores (t = 0.608) of the two age groups, there was a significant difference in the education levels. The REALM scores placed the reading level of the sample at between seventh and eighth grade. The preprinted discharge instruction forms used by the three rural hospitals had a Flesch-Kincaid grade level of 9.0, a reading level higher than 62% of the sample. By ensuring discharge instructions are developed at a reading level of sixth grade or below, nurse practitioners can provide teaching materials that encompass the reading levels of the majority of the rural ED population.

Adding medications in the emergency department: effect on knowledge of medications in older adults.

INTRODUCTION: Older adults constitute 20% of the ED population. Of older patients discharged from the emergency department, 40% receive at least one new medication to add to their already complex medication regimen. The purpose of this study was to determine the effect of increasing medication complexity on knowledge of newly prescribed medications for older adults discharged from the emergency department. METHODS: The complexity of self-administered medications after ED treatment was measured with the Medication Complexity Index to determine its potential influence on the patient's knowledge of medication. The Knowledge of Medication Subtest, a measure of the effectiveness of medication teaching, was administered by telephone interview 48 to 72 hours after ED discharge. RESULTS: Sixty rural ED patients ranging in age from 60 to 98 years completed the study. Higher medication complexity after the addition of medications in the emergency department was associated with less knowledge of their medications (r = 0.37, P =. 004). DISCUSSION: The increase in medication complexity that results from ED therapeutic intervention may decrease knowledge of medications. A heightened emphasis should be placed on effective medication teaching, counseling, and follow-up for older adult ED patients.

Randomized trial of geragogy-based medication instruction in the emergency department.

BACKGROUND: Medication adherence by older adults who are discharged from the emergency department (ED) is an essential attribute of effective treatment. Researchers have demonstrated that delivery of well-structured instructions increases the knowledge of discharge regimens and increases adherence among ED populations. OBJECTIVES: This study compared the level of medication knowledge of elderly ED patients receiving instruction by one of two teaching methods: the usual preprinted discharge instructions with handwritten medication information and individualized computer-generated discharge instructions designed within a geragogy framework. METHOD: The geragogy intervention included large-print, easily readable, specific information ordered within the elderly memory schema. This schema consists of purpose, administration, and emergency information in that order. The Knowledge of Medication Subtest by Horn and Swain (1977) was administered by telephone 48 to 72 hours after discharge. Sixty patients (38 women, 22 men) with a mean age of 76 years were randomly assigned to groups and completed the study at three rural ED sites. RESULTS: Subjects in the geragogy-based intervention group demonstrated significantly more knowledge of medications than did subjects experiencing the usual discharge teaching method (t = 2.19, p = .016). CONCLUSIONS: These findings suggest that a medication teaching intervention geared to the special needs of the elderly can be effective in increasing medication knowledge.