The Influence of US Drug Price Dynamics on Cost-Effectiveness Analyses of Biologics

OBJECTIVES

This study aimed to evaluate the influence of drug price dynamics in cost-effectiveness analyses.

METHODS

We evaluated scenarios involving typical US drug price increases during the exclusivity period and price decreases after the loss of exclusivity (LOE). Worked examples are presented using the Institute for Clinical and Economic Review's assessments of tezepelumab for the treatment of severe asthma and targeted immune modulators for rheumatoid arthritis.

RESULTS

Tezepelumab case: yearly 2% price increases during the period of exclusivity and a post-LOE price decrease of 25% yielded an incremental cost per quality-adjusted life-year (QALY) gained that increased over the base case from $430 300 to $444 600 (+3.2%). Yearly 2% price increases followed by a steeper post-LOE price reduction of 40% resulted in a cost per QALY gained of $401 400 (6.8% reduction vs the base case). Rheumatoid arthritis case: incorporating post-LOE price reductions for etanercept (intervention) and adalimumab (comparator) ranging from 25% to 40% yielded an incremental cost per QALY of $121 000 and $122 300, respectively (< 3% increase from the base case of $119 200/QALY). Including a 2% yearly price increase during the projected exclusivity periods of both intervention and comparator increased the cost per QALY gained by > 60%.

CONCLUSION

Two biologic treatment cases incorporating price dynamics in cost-effectiveness analyses had varied impacts on the cost-effectiveness ratio depending on the magnitude of pre-LOE price increase and post-LOE price decrease and whether the LOE also affected the comparator. Yearly price increase magnitude during the period of exclusivity, among other factors, may counterbalance the effects of lower post-LOE intervention prices.

The effectiveness and value of tezepelumab for severe asthma

DISCLOSURES: Drs Rind, Campbell, Pearson, Ms Herce-Hagiwara, Ms Fluetsch, and Ms Herron-Smith report grants from Arnold Ventures; Kaiser Foundation Health Plan, Inc; The Patrick and Catherine Donaghue Medical Research Foundation; Blue Cross Blue Shield of Massachusetts; and California Healthcare Foundation during the course of this study.

A Randomized Controlled Trial of Heart Failure Disease Management vs Usual Care in Skilled Nursing Facilities

OBJECTIVE

Patients discharged from the hospital to a skilled nursing facility (SNF) are not typically part of a heart failure disease management program (HF-DMP). The objective of this study is to determine if an HF-DMP in SNF improves outcomes for patients with HF.

DESIGN

Cluster-randomized controlled trial.

PARTICIPANTS

The trial was conducted in 47 SNFs, and 671 patients were enrolled (329 HF-DMP; 342 to usual care).

METHODS

The HF-DMP included documentation of ejection fraction, symptoms, weights, diet, medication optimization, education, and 7-day visit post SNF discharge. The composite outcome was all-cause hospitalization, emergency department visits, or mortality at 60 days. Secondary outcomes included the composite endpoint at 30 days, change in the Kansas City Cardiomyopathy Questionnaire and the Self-care of HF Index at 60 days. Rehospitalization and mortality rates were calculated as an exploratory outcome.

RESULTS

Mean age of the patients was 79 ± 10 years, 58% were women, and the mean ejection fraction was 51% ± 16%. At 30 and 60 days post SNF admission, the composite endpoint was not significant between DMP (29%) and usual care (32%) at 30 days and 60 days (43% vs 47%, respectively). The Kansas City Cardiomyopathy Questionnaire significantly improved in the HF-DMP vs usual care for the Physical Limitation (11.3 ± 2.9 vs 20.8 ± 3.6; P = .039) and Social Limitation subscales (6.0 ± 3.1 vs 17.9 ± 3.8; P = .016). Self-care of HF Index was not significant. The total number of events (composite endpoint) totaled 517 (231 in HF-DMP and 286 in usual care). Differences in the 60-day hospitalization rate [mean HF-DMP rate 0.43 (SE 0.03) vs usual care 0.54 (SE 0.05), P = .04] and mortality rate (HF-DMP 5.2% vs usual care 10.8%, P < .001) were significant.

CONCLUSIONS AND IMPLICATIONS

The composite endpoint was high for patients with HF in SNF regardless of group. Rehospitalization and mortality rates were reduced by the HF-DMP. HF-DMPs in SNFs may be beneficial to the outcomes of patients with HF. SNFs should consider structured HF-DMPs for their patients.

The costs and consequences of omalizumab in uncontrolled asthma from a USA payer perspective

BACKGROUND

Omalizumab, an anti-immunoglobulin E antibody, reduces exacerbations and symptoms in uncontrolled allergic asthma. The study objective was to estimate the costs and consequences of omalizumab compared to usual care from a US payer perspective.

METHODS

We estimated payer costs, quality-adjusted survival (QALYs), and the incremental cost-effectiveness ratio (ICER) of omalizumab compared to usual care using a state-transition simulation model that included sensitivity analyses. Every 2 weeks, patients could transition between chronic asthma and exacerbation health states. The best available evidence informed the clinical and cost input estimates. Five years of omalizumab treatment followed by usual care was assumed to estimate a lifetime horizon. Omalizumab responders (60.5% of treated) were modeled as a separate scenario where nonresponders reverted back to usual care after 16 weeks of active treatment.

RESULTS

The mean lifetime discounted costs and QALYs were $83,400 and 13.87 for usual care and $174,500 and 14.19 for omalizumab plus usual care resulting in $287 200/QALY (95% interval: $219,300, $557, 900). The ICER was $172 300/QALY when comparing omalizumab to usual care in the responder scenario. One-way sensitivity analyses indicated that the results were sensitive to the difference in treatment-specific utilities for the chronic state, exacerbation-associated mortality, omalizumab price, exacerbation rates, and response definition.

CONCLUSIONS

The results suggest that adding omalizumab to usual care improves QALYs at an increase in direct medical costs. The cost-effectiveness of omalizumab is similar to other chronic disease biologics. The value increases when omalizumab response is used to guide long-term treatment.

Health economics of asthma: assessing the value of asthma interventions

The aim of this systematic review was to summarize and assess the quality of asthma intervention health economic studies from 2002 to 2007, compare the study findings with clinical management guidelines, and suggest avenues for future improvement of asthma health economic studies. Forty of the 177 studies met our inclusion criteria. We assessed the quality of studies using The Quality of Health Economic Studies validated instrument (total score range: 0-100). Six studies (15%) had quality category 2, 26 studies (65%) achieved quality category 3, and the remaining eight (20%) studies were scored as the highest quality level, category 4. Overall, the findings from this review are in line with the Global Initiative for Asthma clinical guidelines. Many asthma health economic studies lacked appropriate long term time horizons to match the chronic nature of the disease and suffered from using effectiveness measures that did not capture all disease related risks and benefits. We recommend that new asthma simulation models: be flexible to allow for long term time horizons, focus on using levels of asthma control in their structure, and estimate both long term asthma specific outcomes like well-controlled time as well as generic outcomes such as quality adjusted survival.

The response to combination therapy treatment regimens in severe/difficult-to-treat asthma

The aim of the present study was to assess the response of high-dose salmeterol/fluticasone combination (SFC) and low-dose SFC compared with regimens without inhaled corticosteroid (ICS) plus long-acting beta-agonist (LABA) in a large cohort with severe or difficult-to-treat asthma. Subjects were administered low-dose SFC (100/50 or 250/50 microg) or high-dose SFC (500/50 microg), and a control group received medications that could include ICS or LABA but not both. The present authors calculated unadjusted and propensity score-adjusted differences in outcomes consistent with components of asthma control, comparing high-dose and low-dose SFC cohorts with controls. The low-dose SFC cohort had higher asthma-related quality of life and fewer asthma control problems compared with controls. The high-dose SFC cohort had higher forced expiratory volume in one second but higher odds of having severe asthma compared with controls. The present results support the evidence that some asthmatics achieve better outcomes while receiving a low-dose salmeterol/fluticasone combination, but also suggest that those on a high-dose salmeterol/fluticasone combination fail to achieve significant improvement in many control-related health outcomes as compared with similar patients not receiving salmeterol/fluticasone combination. These findings suggest a limited value of high-dose salmeterol/fluticasone combination compared with the alternatives. While additional studies are needed, the present findings call for alternative therapeutic approaches in severe/difficult-to-treat asthma for those unable to attain asthma control with or without salmeterol/fluticasone combination.

Pandemic flu vaccine: are we doing enough?

Influenza experts have been trying for a long time to convince other scientists, the public health community, and the general population that preparations for a pandemic should be a priority. But it was not until the highly pathogenic H5N1 avian strain emerged, causing a great epizootic and infecting and killing people exposed to infected birds, that research on this topic exploded. Below I discuss some truly phenomenal advances that have emerged from this newfound interest in pandemic influenza, to show that, yes, we are doing enough.

Genotypic analysis of invasive Streptococcus pneumoniae from Mali, Africa, by semiautomated repetitive-element PCR and pulsed-field gel electrophoresis

As part of a large, ongoing study of invasive infections in pediatric patients in Bamako, Mali, 106 cases of invasive pneumococcal disease were identified from June 2002 to July 2003 (J. D. Campbell et al., Pediatr. Infect. Dis. J. 23:642-649, 2004). Of the 12 serotypes present, the majority of isolates were not contained in PCV7 (the 7-valent pneumococcal conjugate vaccine), including 1 isolate that was serotype 1, 12 isolates that were serotype 2, 58 isolates that were serotype 5, 7 isolates that were serotype 7F, and 1 isolate that was serotype 12F. To determine whether clonal dissemination of the predominant serotypes had taken place, genotyping was performed on 100 S. pneumoniae isolates by using two methods: pulsed-field gel electrophoresis (PFGE) of SmaI-digested genomic DNA, and the Bacterial Barcodes repetitive-element PCR (rep-PCR) method. Criteria for delineating rep-PCR genotypes were established such that isolates of different serotypes were generally not grouped together. The two methods were equally discriminatory within a given pneumococcal serotype. PFGE separated the isolates into 15 genotypes and 7 subtypes; rep-PCR separated isolates into 15 genotypes and 6 subtypes. Using either method, isolates within serotypes 2, 5, and 7 formed three large, separate clusters containing 1 genotype each. Both methods further distinguished related subtypes within serotypes 2 and 5. Interestingly, one of the PFGE subtypes of serotype 5 is indistinguishable from the Columbia(5)-19 clone circulating in Latin America since 1994. The data support that serotypes 2 and 5 were likely to be the result of dissemination of particular clones, some of which are responsible for invasive disease over a broad population range.

Lifestyle, minerals and health

This paper proposes that most poor health and behavioral conditions are related to a deficiency of essential minerals or an excess of toxic ones. Clients requesting a hair mineral analysis were required to complete a questionnaire including lifestyle, health status and diet. Most prevalent health conditions in order of frequency were: depression, allergies, low back pain, arthritis, cardiovascular disease and poor digestion. Most deficient minerals were chromium, magnesium, zinc and calcium. Aluminum was the most frequent toxic mineral. it is proposed that such mineral abnormalities were caused by an over consumption of nutrient-poor, highly processed foods such as white flour, sugar and harmful fats. Such a diet promotes poor lifestyles such as smoking, drug abuse, alcoholism and criminal activity. Poor diets and dangerous lifestyles precedes the development of most prevalent diseases. The most common one is cardiovascular disease which increased at an alarming rate in the last century.

In vivo stability of human chemokine and chemokine receptor expression

Cross-sectional analyses of human PBMC, plasma, and tissue have reported altered chemokine and/or chemokine receptor expression in several inflammatory diseases. Interpretation of such studies is difficult without data on the in vivo stability of such parameters. Using four color flow cytometry, we longitudinally followed CXCR3, CCR5 (Th1-associated), and CCR3 (Th2-associated) expression within CD4+/CD45RO+ and CD8+/CD45RO+ T cell populations in peripheral blood of healthy individuals over a 21 day period. In parallel, we quantified plasma levels of IP-10, Mig, eotaxin and TARC. Chemokine and receptor expression differed markedly between subjects but was highly stable, varying by <5% within individuals. Differences in chemokine receptor expression between subjects were markedly altered when quantified as absolute cell numbers rather than frequencies. Finally, CCR3 expression by CD4+/CD45RO+ T cells was positively correlated with plasma levels of its ligand, eotaxin, whereas strong negative correlations were evident between CXCR3 expression and IP-10 or Mig. These data demonstrate longitudinal stability of chemokine receptor and ligand expression among healthy individuals; reveal that both frequency and absolute cell count analysis is essential for accurate assessment of chemokine receptor expression; and identify inverse relationships between type 1 and type 2 immunity-associated receptors and their ligands in vivo.

Suppression of IL-2-induced T cell proliferation and phosphorylation of STAT3 and STAT5 by tumor-derived TGF beta is reversed by IL-15

IL-2 responses are susceptible to suppression by TGFbeta, a cytokine widely implicated in suppression of inflammatory responses and secreted by many different tumor cell types. There have been conflicting reports regarding inhibition of IL-2-induced STAT3 and STAT5 phosphorylation by TGFbeta and subsequent suppression of immune responses. Using TGFbeta-producing multiple myeloma tumor cells we demonstrate that tumor-derived TGFbeta can block IL-2-induced proliferation and STAT3 and STAT5 phosphorylation in T cells. High affinity IL-2R expression was required for the suppression of IL-2 responses as a novel CD25(-) T cell line proliferated and phosphorylated STAT3 when cultured with tumor cells or rTGFbeta1. Activating T cells with IL-15, which does not use the high affinity IL-2R, completely restored the ability of T cells to phosphorylate STAT3 and STAT5 when cultured with tumor cells. IL-15-treated T cells proliferated normally when cocultured with tumor cells or rTGFbeta1, whereas IL-2 responses were consistently inhibited. Preincubation with IL-15 also restored the ability of T cells to respond to IL-2 by phosphorylating STAT3 and STAT5, and proliferating normally in the presence of tumor cells. IL-2 pretreatment did not restore T cell function. IL-15 also restored T cell responses by T cells from multiple myeloma patients, and against freshly isolated bone marrow tumor samples. Thus, activation of T cells by IL-15 renders T cells resistant to suppression by TGFbeta1-producing tumor cells and rTGFbeta1. This finding may be exploited in the design of new immunotherapy approaches that will rely on T cells avoiding tumor-induced suppression.

Introducing telemedicine technology to rural physicians and settings

OBJECTIVE

The researchers investigated rural health providers' perceptions of telemedicine, developed a framework for assessing their readiness to adopt this type of technology, and offered a guide for its implementation.

STUDY DESIGN

Qualitative data were collected from semistructured interviews with thematic analysis.

POPULATION

The study population included physicians, nurses, and administrative personnel located in 10 health care practices in 4 communities in 3 rural Missouri counties.

OUTCOMES MEASURED

The researchers measured how often health providers used telemedicine technology and their perceptions of the advantages, disadvantages, barriers, and facilitators involved in adopting it.

RESULTS

Participants varied widely in their perceptions of telemedicine. Providers in practices affiliated with the university's tertiary center were more likely to use it than were those in private practice. Interviews and other data yielded 6 themes related to a provider's receptivity to technological change: These themes were turf, efficacy, practice context, apprehension, time to learn, and ownership. Each theme applies to the computer and videoconferencing components of telemedicine, and each may operate as a perceived barrier or facilitator of change.

CONCLUSIONS

Care providers and administrators consider a range of factors, including economic ramifications, efficacy, social pressure, and apprehension, when deciding whether and how fast to adopt telemedicine. Since adopting this technology can be a major change, agencies trying to introduce it into rural areas should take all these factors into account in their approach to health care providers, staff, and communities.

Proinflammatory cytokine expression by Theileria annulata infected cell lines correlates with the pathology they cause in vivo

Control of Theileria annulata is currently best achieved by the use of live attenuated cell line vaccines. However, the mechanisms underlying attenuation are unclear and there is a need to rapidly produce new cell line vaccines, which could safely and effectively vaccinate cattle against tropical theileriosis. There is increasing evidence to suggest that proinflammatory cytokines produced by T. annulata infected cells play a central role in both pathology and immune evasion. This study aimed to test this hypothesis and to evaluate cytokine expression as a marker of virulence. The pathogenicity and protective efficacy of cloned T. annulata cell lines that expressed different levels of proinflammatory cytokines were compared. In two independent trials using different stocks of T. annulata, cell lines that expressed higher levels of proinflammatory cytokines induced severe reactions, and in some cases death, when used to vaccinate groups of cattle. In contrast, low cytokine expressing lines induced low post-vaccinal reactions. The results clearly demonstrated that cytokine expression by T. annulata infected cells could be used as a marker of virulence and provided strong evidence to support a role for cytokines in the induction of pathology. Both high and low cytokine expressing cell lines protected cattle against heterologous challenge infection, offering the possibility of using cytokine expression to rapidly select new safe, potent vaccines against tropical theileriosis without the need for culture attenuation.

T cell chemokine receptor expression in human Th1- and Th2-associated diseases

The interaction between chemokines and their receptors is an important step in the control of leukocyte migration into sites of inflammation. Chemokines also mediate a variety of effects independent of chemotaxis, including induction and enhancement of Th1- and Th2-associated cytokine responses. Recent studies have shown that human Th1 and Th2 clones, activated under polarizing conditions with polyclonal stimuli in vitro, display distinct patterns of chemokine receptor expression: Th1 clones preferentially express CCR5 and CXCR3, while many Th2 clones express CCR4, CCR8 and, to a lesser extent, CCR3. These differential patterns of chemokine receptor expression suggest a mechanism for selective induction of migration and activation of Th1- and Th2-type cells during inflammation and, perhaps, normal immune homoeostasis. Studies have begun to examine T cell chemokine receptor expression in vivo to determine the relevance of these in vitro observations to human Th1- and Th2-associated diseases. In this review, we critically examine recent reports of T cell chemokine receptor expression in human autoimmune disorders (multiple sclerosis and rheumatoid arthritis) and atopic disorders (allergic rhinitis and asthma) which are believed to arise from inappropriate Th1- and Th2-dominated responses, respectively.

Evolution of bone marrow transplantation--the original immunotherapy

Allogeneic bone-marrow transplantation (BMT) has provided a curative treatment option for chronic myeloid leukaemia (CML) over the past 20-30 years. New drugs - signal transduction inhibitors - that target the bcr-abl oncogene have the potential to render such transplantation procedures obsolete and provide hope for those without a suitable donor ( approximately 60% of patients). Here, we discuss how new drug and immune-based approaches could be combined to enhance treatment of this already 'curable' malignancy.

Comparison of chemiluminescent assays and colorimetric ELISAs for quantification of murine IL-12, human IL-4 and murine IL-4: chemiluminescent substrates provide markedly enhanced sensitivity

Many available ELISAs lack the sensitivity required to reliably quantify levels of cytokines released in response to antigenic stimulation. In an effort to increase sensitivity of these assays, we compare the sensitivity of standard colorimetric ELISAs and corresponding chemiluminescent assays for three cytokines which are usually produced in very low quantities: mouse IL-12 p70, human IL-4 and mouse IL-4. Use of a chemiluminescent substrate enhanced the sensitivity of these assays 12-29-fold as compared to current colorimetric ELISAs. Accompanying this increase in sensitivity was an increase in dynamic range, a decrease in the time required to obtain maximum sensitivity and a decrease in the concentration of reagents required. These findings are of particular interest to those wanting to quantitate levels of any cytokine which is typically produced in low levels.

The Th1-Th2 classification of cellular immune responses: concepts, current thinking and applications in haematological malignancy

The finding that T cell immune responses could be divided into those promoting cell mediated immunity (Th1) and humoral responses (Th2) has had a profound effect on the understanding of immune response generation over the last 15 years. With ever increasing knowledge of the immune system, the model has come under criticism, as not all responses easily fit the classification. Nonetheless, the model still provides a valuable framework on which to base immunological research. In this review we update the model with current thinking regarding the generation and maintenance of immune responses. We then examine how the Th1-Th2 paradigm may be applied in developing new understanding of several topical issues in haematological malignancy-control of graft-versus-host disease; cytokine control of proliferating clones in B and T cell diseases; and suppression of T cell responses in multiple myeloma.

The no-show rate in a high-risk obstetric clinic

We wished to determine the reasons for an average missed appointment rate of 28% in a high-risk pregnancy clinic. Only 41% of the 261 women in the study group could be reached by telephone. The reasons included not having a phone, the phone had been disconnected, incorrect phone number on the chart, the patient had moved, and the patient did not respond to the answering machine message. The reasons for missing the appointment included lack of transportation, scheduling problems, overslept or forgot, presence of a sick child or relative, and lack of child care. The response of patients to assessing prenatal care may reflect their priority of medical care relative to other priorities associated with day-to-day existence. There may be a baseline missed appointment rate for prenatal care in lower socioeconomic populations of women. The commitment of personnel time and energy to attempt to modify the no-show rate should be reexamined.

Experimental approaches to analysis of immune dysregulation in human allergic disease

Over the last 40 years, much attention has been directed towards identification of the immunologic, genetic and environmental factors that predispose towards development of allergic disease. An implicit assumption in many such studies is that clinical tolerance reflects from immunologic tolerance. Here we critically review the conceptual background and experimental data arguing for the alternative hypothesis that failure to develop atopic disease reflects the success of type 1 dominated immunity that constitutively impedes development of type 2 responses to environmental antigens, hence, clinical immediate hypersensitivity. We report that endogenous production of type 1 chemokines such as IP-10 by non-atopic individuals may play a substantive role in maintaining this putatively protective type 1 bias in non-atopic subjects. Polyclonal activators (superantigen TSST-1, anti-CD3, PHA) were used to activate distinct intracellular signaling pathways, inducing quantitatively different IFNgamma:IL-4 ratios in primary culture of human PBMC. In parallel, physiologic stimuli such as grass pollen or cat antigen were used to evaluate the impact of IP-10 on CD4 T cell dependant, chloroquine-sensitive cytokine synthesis. IFNgamma responses by non-atopic subjects were markedly increased in the presence of nM concentrations of rhIP-10 while type 2 cytokine synthesis remained unaffected. Optimal rIP-10 concentrations for promoting expression and maintenance of type 1 cytokine synthesis in vitro (0.1 to 10 ng/ml) were at or well below those generally used for chemotaxis (5 to 100 ng/ml). Collectively, our findings suggest a potential role for this T cell focused chemokine in maintaining the default type 1 responses usually caused to environmental antigens in non-atopic subjects. These may play a role in determining the relative susceptibility of individuals to develop atopic disease. Taken together with recent reports of other roles played by chemokines in shaping the nature of immune responses, the data suggest that constitutive, endogenous type 1 chemokine synthesis may play a homeostatic role in inhibiting development of atopic disease.

C-C chemokine receptor 3 antagonism by the beta-chemokine macrophage inflammatory protein 4, a property strongly enhanced by an amino-terminal alanine-methionine swap

Allergic reactions are characterized by the infiltration of tissues by activated eosinophils, Th2 lymphocytes, and basophils. The beta-chemokine receptor CCR3, which recognizes the ligands eotaxin, eotaxin-2, monocyte chemotactic protein (MCP) 3, MCP4, and RANTES, plays a central role in this process, and antagonists to this receptor could have potential therapeutic use in the treatment of allergy. We describe here a potent and specific CCR3 antagonist, called Met-chemokine beta 7 (Ckbeta7), that prevents signaling through this receptor and, at concentrations as low as 1 nM, can block eosinophil chemotaxis induced by the most potent CCR3 ligands. Met-Ckbeta7 is a more potent CCR3 antagonist than Met- and aminooxypentane (AOP)-RANTES and, unlike these proteins, exhibits no partial agonist activity and is highly specific for CCR3. Thus, this antagonist may be of use in ameliorating leukocyte infiltration associated with allergic inflammation. Met-Ckbeta7 is a modified form of the beta-chemokine macrophage inflammatory protein (MIP) 4 (alternatively called pulmonary and activation-regulated chemokine (PARC), alternative macrophage activation-associated C-C chemokine (AMAC) 1, or dendritic cell-derived C-C chemokine (DCCK) 1). Surprisingly, the unmodified MIP4 protein, which is known to act as a T cell chemoattractant, also exhibits this CCR3 antagonistic activity, although to a lesser extent than Met-Ckbeta7, but to a level that may be of physiological relevance. MIP4 may therefore use chemokine receptor agonism and antagonism to control leukocyte movement in vivo. The enhanced activity of Met-Ckbeta7 is due to the alteration of the extreme N-terminal residue from an alanine to a methionine.

Why geriatrics? Academic geriatricians' perceptions of the positive, attractive aspects of geriatrics

BACKGROUND

Recruitment of geriatrics trainees has been poor, and the current shortage of academic geriatricians is expected to worsen. Although barriers to entering geriatrics practice have been identified, a review of the literature found few studies about why people choose to enter geriatrics.

METHODS

We used qualitative methods to investigate the positive, attractive aspects of geriatrics. Long interviews with six academic geriatricians were taped and transcribed. Transcripts were entered into a textual database computer program and reviewed independently by two investigators.

RESULTS

Six themes emerged: 1) traditional learning experiences, 2) value on personal relationships, 3) a perception of distinctive differences, 4) a desire to feel needed personally and societally, 5) prefer democracy versus autocracy, and 6) desire intellectual challenges. Academic geriatrics, therefore, is particularly attractive to people who value enduring relationships, see challenges in complexity, practice social responsibility, prefer working within a multidisciplinary team, and derive satisfaction from making seemingly small but nonetheless important changes in peoples' lives.

CONCLUSIONS

If further studies validate these findings, they could promote geriatrics as a career, by, for example, identifying students and family practice and internal medicine residents who share these values, beliefs, and attitudes and encouraging them to consider this important field.

Transforming growth factor beta from multiple myeloma cells inhibits proliferation and IL-2 responsiveness in T lymphocytes

Multiple myeloma (MM) is a cancer of plasma cells, characterized by profound suppression of host immune responses. Here we show that MM cell lines significantly suppress the proliferation, blasting, response to interleukin-2 (IL-2), and expression of CD25 by concanavalin A (Con A)-activated or allostimulated peripheral blood T lymphocytes. T cells arrest in the G1 stage of the cell cycle, and do not enter the IL-2 autocrine growth pathway. T cell inhibition was mediated by a soluble factor. MM cell lines did not produce IL-10 but did produce large amounts of transforming growth factor beta1 (TGF-beta1). T cells were assessed for their ability to respond to IL-2 when co-cultured with MM cells in the presence or absence of the TGF-beta inhibitor, TGF-beta latency-associated peptide (LAP). MM cells suppressed IL-2 responses but this inhibition was completely reversed by TGF-beta LAP. A CD25-, IL-2-dependent blast cell line was not inhibited by MM cells or rhTGF-beta, confirming the specificity of the inhibition mechanism for the IL-2 autocrine growth pathway. We conclude that MM cells suppress T cells in their entry into the autocrine IL-2/CD25 pathway and in response to IL-2, and that TGF-beta has a significant role to play.

Immune regulation in multiple myeloma: the host-tumour conflict

Multiple myeloma (MM) remains essentially incurable by conventional anti-tumour therapy. This has led to increased interest in the possibility that forms of immune therapy might be effective. The successful use of donor lymphocyte infusions (DLI) in a few cases of MM relapse following allogeneic bone marrow transplantation have added weight to this view. MM is characterized by several defects in the host's immune system. The influence of the malignant clone on the function of the immune effector cells results from both passive and active suppression. Despite an array of functional adhesion molecules and HLA class I and II molecules on their surface and the secretion of a tumour-specific peptide, they fail to express adequate levels of co-stimulatory molecules thus inducing anergy in potentially tumour-specific T cells. In addition to this passive evasion of immune regulation, MM tumour cells are capable of producing a number of immunologically active agents which can induce immunosuppression such as transforming growth factor-beta, Fas ligand (FasL), vascular endothelial growth factor and Muc-1. It is postulated that these agents may be produced by the tumour cell to influence the microenvironment to support growth and differentiation of the clone but may have the additional benefit of altering the function of the host immune effector cells and thus preventing tumour rejection. This duality of function is important if clinicians are to design immunotherapy strategies which will achieve the true potential and result in improved survival in MM.

The proliferation-associated nuclear protein Ki-67 in the bovine system: partial characterisation and its application for determination of the proliferation of Theileria-infected bovine cells

Theileria annulata-infected bovine cells as well as mitogen-stimulated bovine peripheral blood mononuclear cells (PBMC) express a proliferation-associated nuclear protein equivalent to the human Ki-67 protein. In analogy to the human system, the expression of the bovine Ki-67 protein is restricted to proliferating cells only, since (a) Ki-67 expression paralleled [3H]-thymidine incorporation in concanavalin A (Con A)-stimulated bovine PBMC, (b) Ki-67 was not detectable in quiescent bovine cells, and (c) Ki-67 expression in Theileria-infected cells is related to the presence of the parasites within the cytoplasm of the host cells; upon treatment with the theilericidal drug buparvaquone the parasites are destroyed and the cells cease to proliferate and to express the Ki-67 protein. Western-blot analysis of lysates of proliferating bovine cells revealed that the prototype monoclonal antibody Ki-67 and the new equivalent antibody MIB-1 detected one prominent protein band with an apparent molecular weight of 430 kDa. Two cDNA clones (pUC18.B1.Ki-67 and pUC18.B2.Ki-67) were isolated from a lambdagt11 cDNA library of T. annulata-infected bovine cells by immunoscreening with the monoclonal antibody MIB-1. Comparison of these cDNA sequences with those of the human Ki-67 protein revealed 60-70% identity. Within the "Ki-67 motif", identity proved to be 80% at the amino acid level. The remarkable identity between bovine and human Ki-67 proteins suggests that MIB-1 can be used as a marker for cell proliferation in animal research. In this context we could identify proliferating cells in lymph nodes of Theileria-infected animals and, furthermore, we could distinguish between infected and uninfected proliferating cells using MIB-1 and an antiserum against a recombinant parasite protein designated SA288.

Innate and adaptive immune responses co-operate to protect cattle against Theileria annulata

For many years it was assumed that Theileria annulata resembled T. parva, parasitizing lymphocytes and causing lymphoproliferative disease, with the two species being controlled by similar protective immune responses. Patricia Preston et al. here review the evidence that has led to a different view of T. annulata. It is now thought that the schizonts of T. annulata inhabit macrophages and B cells, and that tropical theileriosis is not a lymphoproliferative disease. Both innate and adaptive responses contribute to recovery from infection and resistance to challenge and cytokines produced by infected and uninfected cells influence the outcome of infection. Partial protection has been stimulated recently by defined recombinant antigens; efficacy depended upon the delivery system.

Pneumococcal vaccines

Despite advances in our knowledge of the pathogenesis and host immune response and efforts at prevention and treatment, S. pneumoniae continues to cause considerable disease and mortality. The currently available polysaccharide vaccines confer moderate protection in most adults and older children, but they are underutilized. There are an estimated 40,000 deaths per year among U.S. adults due to pneumococcus, of which nearly half might be prevented if the current recommendations for vaccination were followed. Future advances must include augmented efforts at coverage of older children and adults via improvements in education, delivery mechanisms and financing. The major advance in the field is the development of conjugate vaccines which appear safe, immunogenic and efficacious against invasive pneumoccocal disease in infants. The first conjugate vaccine is anticipated to be available for use in the U.S. in the year 2000.

Ascorbic acid is a potent inhibitor of various forms of T cell apoptosis

This study was designed to examine the effect of ascorbic acid (vitamin C) on various death pathways of mouse T cells. Unlike humans, mice produce their own ascorbic acid and our study tested the effect of additional ascorbic acid on murine T cells. Our data show that three T cell death pathways (growth factor withdrawal-, spontaneous-, and steroid-induced death) were inhibited when T cells were incubated with ascorbic acid. The data show that both activated and resting T cells were responsive to ascorbic acid since both populations were resistant to death stimuli when treated with ascorbic acid. Additionally, effector T cells were more likely to enter S phase if treated with ascorbic acid. Our data implicate ascorbic acid as a potent inhibitor of various forms of T cell death and suggest that vitamin C may function as an immune booster through this mechanism.

Diminished IL-2 responses and alteration of CD2 expression on CD8+ T cells are associated with a lack of cytotoxic T cell responses during Theileria annulata infection

Theileria annulata is a tick-borne protozoan parasite which causes the disease bovine tropical theileriosis. In immunized or drug-treated animals, the pathogenic macroschizont stage of the parasite is destroyed by MHC class I-restricted cytotoxic T lymphocytes (CTL). Here we show that although CD8+ T cells increase greatly in number and display activation markers during an acute infection, they exhibit no killing of infected cells. During the ineffectual response, efferent lymph cells' ability to proliferate to IL-2 drops, coinciding with loss of MoAb binding to CD2 by CD8+ cells. When animals were treated with the anti-parasite drug 'Butalex', IL-2 responses, anti-CD2 antibody binding by CD8+ cells and strong CTL activity were restored within 24 h. The initial activation of CD4+ T cells by parasite-infected cells altering the IL-2 production in the draining lymph node is the likely cause of the failure of CTL responses.

In vivo development of Theileria annulata: major changes in efferent lymph following infection with sporozoites or allogeneic schizont-infected mononuclear cells

The object of these experiments was to study the pathogenesis and kinetics of Theileria annulata infection in the efferent lymph of the draining lymph nodes of calves. Efferent lymphatics of calves were cannulated prior to infection with T. annulata sporozoite or an allogeneic schizont cell line. Potentially lethal sporozoite challenge induced cell shut-down from days 4-6 and then a massive increase in output of blasting cells (both infected and non-infected) in the efferent lymph. The rate of lymph flow and total cell output increased to 5 to 10-fold from day 6 onwards. Sporozoites were never isolated from the efferent lymph. However, large numbers of parasite-infected cells were seen in efferent lymph from the sixth day of infection. The animals inoculated with an allogeneic T. annulata-infected cell line exhibited only a small increase in flow rate and cell output. Parasite-infected cells of recipient origin were seen in efferent lymph from day 11 onwards. However, cells of donor origin were never isolated either from efferent lymph or peripheral blood. Thus the parasite transferred from the inoculated donor cell line to the cells of the recipient before schizonts appeared in efferent lymph.

Private self-consciousness and the five-factor model of personality: distinguishing rumination from reflection

A distinction between ruminative and reflective types of private self-attentiveness is introduced and evaluated with respect to L. R. Goldberg's (1982) list of 1,710 English trait adjectives (Study 1), the five-factor model of personality (FFM) and A. Fenigstein, M. F. Scheier, and A. Buss's (1975) Self-Consciousness Scales (Study 2), and previously reported correlates and effects of private self-consciousness (PrSC; Studies 3 and 4). Results suggest that the PrSC scale confounds two unrelated, motivationally distinct dispositions--rumination and reflection--and that this confounding may account for the "self-absorption paradox" implicit in PrSC research findings: Higher PrSC scores are associated with more accurate and extensive self-knowledge yet higher levels of psychological distress. The potential of the FFM to provide a comprehensive framework for conceptualizing self-attentive dispositions, and to order and integrate research findings within this domain, is discussed.

CD40 activation boosts T cell immunity in vivo by enhancing T cell clonal expansion and delaying peripheral T cell deletion

In this report we show that activation of APC with an agonist anti-CD40 mAb profoundly alters the behavior of CD4 T cells in vivo. Stimulation of mice with anti-CD40 2 days before, but not 1 day after, administration of superantigen (SAg) enhanced CD4 and CD8 T cell clonal expansion by approximately threefold. Further, CD40 activation also delayed peripheral T cell deletion after activation. Dying, activated T cells were quantitated by detecting extracellular phosphatidylserine with concomitant staining for SAg-reactive T cells using a TCR Vbeta-specific mAb. Upon close examination, it was shown that CD40 activation delayed the death of the activated T cells. Additionally, it was found that enhanced survival of CD4 T cells was equally dependent on APC expression of B7-1 and B7-2. This is in contrast to CD8 T cells, which did not depend as much on B7-1 as B7-2. Thus, CD40 activation indirectly promotes T cell growth and delays the death of SAg-stimulated CD4 T cells in vivo. These data suggest that one way CD40 activation promotes a more robust immune response is by indirectly increasing the production of effector T cells and by keeping them alive for longer periods of time.

Private self-consciousness and the five-factor model of personality: distinguishing rumination from reflection

A distinction between ruminative and reflective types of private self-attentiveness is introduced and evaluated with respect to L. R. Goldberg's (1982) list of 1,710 English trait adjectives (Study 1), the five-factor model of personality (FFM) and A. Fenigstein, M. F. Scheier, and A. Buss's (1975) Self-Consciousness Scales (Study 2), and previously reported correlates and effects of private self-consciousness (PrSC; Studies 3 and 4). Results suggest that the PrSC scale confounds two unrelated, motivationally distinct dispositions--rumination and reflection--and that this confounding may account for the "self-absorption paradox" implicit in PrSC research findings: Higher PrSC scores are associated with more accurate and extensive self-knowledge yet higher levels of psychological distress. The potential of the FFM to provide a comprehensive framework for conceptualizing self-attentive dispositions, and to order and integrate research findings within this domain, is discussed.

Long-term effects of perindopril on metabolic parameters and the heart in the spontaneously hypertensive/NIH-corpulent rat with non-insulin-dependent diabetes mellitus and hypertension

The spontaneously hypertensive/NIH-corpulent (SHR/N-cp) rat is a genetic model that exhibits both non-insulin-dependent diabetes mellitus (NIDDM) and hypertension. To determine the impact of long-term treatment with the long-acting angiotensin-converting enzyme (ACE) inhibitor perindopril (PE) on the glucose metabolism, lipid levels, and heart in this model, studies were performed in three groups of SHR/N-cp rats maintained on a diet containing 54% carbohydrate with 18% sucrose and 36% starch. One group of obese rats received PE (0.5 to 1.0 mg/kg body weight/d) for 3 to 4 months, a second group of obese rats received no treatment, and a third group of lean rats were used as controls. The mean systolic blood pressure (SBP) increased gradually in both untreated obese and lean rats, with lean animals showing slightly higher levels compared with untreated obese rats. By contrast, SBP was reduced to normal levels in PE-treated obese rats throughout the treatment period. Compared with lean rats, obese rats showed significantly higher body weight and fasting serum levels of glucose, insulin, total cholesterol (TC), and triglyceride (TG). However, no significant differences were observed in these metabolic parameters between PE-treated and untreated obese rats. Plasma renin activity measured at the end of the treatment period was significantly higher in PE-treated rats compared with untreated obese and untreated lean rats. The mean heart weight and left ventricular weight, expressed in absolute terms or indexed to body weight, were significantly lower in PE-treated versus untreated obese and untreated lean rats. To further determine whether glucose metabolism is directly affected by PE treatment, in vitro glycogen synthesis was evaluated in isolated soleus muscles obtained from three additional groups of animals. The basal rate of muscle glycogen synthesis was significantly lower in obese compared with lean rats (P < .05), but did not differ between PE-treated and untreated obese rats. Maximal insulin-stimulated glycogen synthesis increased threefold in PE-treated obese rats, but this increase did not differ from the increases observed in untreated obese and lean rats. In conclusion, the present study shows that long-term PE treatment in obese SHR/N-cp rats with NIDDM and hypertension effectively controlled systemic arterial pressure and resulted in a significant reduction in left ventricular weight. However, these favorable effects of PE were not associated with significant improvement in glucose tolerance, hyperinsulinemia, and hyperlipidemia in this model. PE also had no direct stimulatory effects on either basal or insulin-mediated glycogen synthesis in the isolated soleus muscle of obese rats, perhaps because of the severe insulin-resistant state of the animals. Our results support the clinical observations that antihypertensive therapy with ACE inhibitors has neutral effects on glucose metabolism and insulin sensitivity in patients with combined hypertension and NIDDM.

Evidence for strain specificity in cytotoxic T-lymphocyte-mediated, major histocompatibility complex class I-dependent killing of Theileria annulata-infected cells

Cattle immunised against Theileria annulata with one parasite strain have been found to be immune to re-challenge with different strains of the parasite. However, recent evidence of apparent strain specificity has been documented in cattle immunised with attenuated parasite-infected cells. In this study the strain specificity of major histocompatibility complex class I-restricted cytotoxic T-lymphocytes (CTL), a major anti-parasite effector mechanism, was examined. CTL generated following challenge with the Hissar (Indian) strain effectively lysed autologous cells infected with this strain of the parasite. However, CTL were less effective against cells infected with the Gharb (Moroccan) strain and showed virtually no reactivity against the Ankara (Turkish) strain, providing the first direct evidence for strain specificity in immune responses against T. annulata.

A stage-specific, parasite-induced, "window" of in vivo interferon-gamma production is associated with pathogenesis in Theileria annulata infection

The tick-borne protozoan parasite Theileria annulata causes tropical theileriosis, a severe leukoproliferative disease of cattle, which naive susceptible animals fail to control. The parasite infects and transforms macrophages, developing in the local draining lymph node. IFN gamma has been shown to block parasite development in newly infected cells, and inhibits the growth of fully differentiated macroschizont stage-infected cells in vitro. However, the parasite has been found to specifically induce IFN gamma production by T cells and appears to flourish in the face of this T cell-derived response in vivo. Here we show that the production of IFN gamma in vivo is tightly controlled by the parasite. Induction of cytokine production by T cells is not initiated until the parasite has developed beyond the IFN gamma sensitive trophozoite stage. Cytokine production is kept high as infected macrophages develop, and IFN gamma appears to play an active role in maintaining the growth of these cells. Once the infection is fully established, IFN gamma is down regulated, avoiding potential inhibitory effects. Thus by controlling T cell IFN gamma production, the parasite induces a "window" of cytokine expression which promotes its own growth, but avoids potential inhibitory effects of the cytokine.

Stereospecific pharmacokinetics of free and protein-bound ketoprofen in serum and synovial fluid of horses after intravenous and intramuscular administration

OBJECTIVE

To determine intravascular and intrasynovial pharmacokinetics of the R and S enantiomers of ketoprofen after i.v. and i.m. administration to horses.

ANIMALS

6 healthy adult mares.

PROCEDURE

Horses were weighed and ketoprofen (2.2 mg/kg of body weight) was administered i.v. Blood and synovial fluid samples were obtained and analyzed for concentrations of the R and S enantiomers by means of a modified reverse-phase stereospecific high-pressure liquid chromatographic method. Three weeks later, the procedure was repeated, except that ketoprofen was given IM. Protein binding of ketoprofen enantiomers was determined by means of ultrafiltration. Nonlinear least squares methods were used to calculate pharmacokinetic parameters.

RESULTS

Data obtained after i.v. administration best fit an open, two-compartment model. Mean +/- SD S-to-R serum concentration ratios after i.v. and i.m. administration were 1.36 +/- 0.214 and 1.34 +/- 0.245, respectively. Intrasynovial concentrations of the R and S enantiomers of ketoprofen could be measured for only the first 3 hours after i.v. administration; concentrations were less than the limit of quantification by 4 hours after i.v. administration and at all times after i.m. administration. Extent of protein binding of the R enantiomer was not significantly different from extent of protein binding of the S enantiomer; extent of protein binding did not appear to be concentration dependent. Mean free S-to-free R serum concentration ratios, adjusted for protein binding, after i.v. and i.m. administration were 1.58 and 1.56, respectively.

CONCLUSIONS

The R and S enantiomers of ketoprofen are rapidly absorbed and eliminated, have low volumes of distribution, and are highly protein bound.

A novel cell surface proliferation-associated marker expressed on T cells and up-regulated on germinal center B cells

In this study we present data on a novel cell surface antigen recognized by monoclonal antibody (mAb) VPM30, originally thought to recognize only bovine and ovine sIg+ B cells from peripheral blood. Here we show that the antigen, molecular mass 28 kDa, is not only found in B cell follicles in frozen sections, but when used on paraffin sections VPM30 specifically stains B cells in the light zone of germinal centers but not in the mantle or dark zones. In addition we show that the antigen is also expressed by 90% of T cells after activation, with kinetics of antigen expression mirroring those of proliferation. By both size and distribution, the antigen appears to be novel, corresponding to no known cluster of differentiation, and will be of great use in the study of ruminant cellular immune responses.

Parasite-mediated steps in immune response failure during primary Theileria annulata infection

"Exotic" European cattle are highly susceptible to T. annulata infection. In immunised animals, several effective anti-parasite responses can be demonstrated, such as anti-macroschizont cytotoxic T cells (CTL), and nitric oxide killing of parasites. The failure of infected animals to mount an effective primary immune response suggests that the presence of the parasite directly interferes with the development of immunity. When the activation pathways of CD4+ T cells in draining lymph nodes were examined during the course of a primary infection it was found that the development of this essential arm of the immune response was altered. Instead of interacting with antigen presenting cells in the paracortex, the majority of CD4+ T cells were rapidly activated by developing infected cells in the medulla of the node. Activation of T cells by infected cells also drastically alters the cytokines produced by the T cells. During effective immune responses, the principal cytokine involved appears to be IL-2, with only small, controlled "bursts" of IFN gamma production. However, IL-2 responsiveness is only transient in animals undergoing primary infection, while IFNg production is greatly elevated. IFN gamma does not appear to control parasitised cells, and may even aid the growth of infected macrophages--large numbers of macrophages enter the cell cycle during the peak period of IFN gamma production. Uncontrolled parasite-induced IFN gamma production is also likely to account for the local failure of antibody responses. Germinal centres in infected lymph nodes lose normal morphology, with IFN gamma sensitive zones failing to develop. A third strategy which the parasite uses to evade immune response destruction is through affecting CTL activity. CTL in infected draining lymph nodes lose expression of the adhesion molecule CD2--a molecule is essential in adherence to target cells for lysis. CD2- CTL are unable to lyse macroschizont infected cells.

Allograft responses can interfere with the development of immunity against Theileria annulata following vaccination with parasite infected cell lines

Theileria annulata macroschizont-infected cell lines are successfully used as vaccines in several countries. The inoculated animals produce a strong allogeneic response against the MHC antigens of the immunizing cell line followed by an anti-parasite response. Immunity against the parasite wanes in the absence of challenge and re-immunization is sometimes recommended. However, it is not known if allogeneic responses generated by the first immunization with a T. annulata infected cell line will interfere with the boosting of immunity against the parasite at the time of re-immunization with the same cell line. Animals were primed against MHC antigens by skin grafting, followed by immunization with a T. annulata infected cell line prepared from the skin donor. A strong anti-MHC response was produced. This interfered with parasite transfer and the development of an anti-parasite immune response; the effect was more marked when a low vaccine cell dose was used. There was a negative correlation between the ease of isolating infected cells from the animals after cell line immunization, and the subsequent response to challenge. Where no cell lines could be isolated, the animals were fully susceptible to sporozoite challenge. These observations are of immediate importance in endemic areas where cell lines of T. annulata schizonts are being used as vaccines to control the disease.

A non-protective T helper 1 response against the intra-macrophage protozoan Theileria annulata

Theileria annulata is a protozoan parasite which infects and transforms bovine macrophages. Infected macrophages possess augmented antigen presentation capabilities, as they are able to activate the majority of T cells from unexposed animals. In vivo, T cells in the draining lymph node (principal site of parasite development) are activated 'non-specifically' by the parasite. This event is followed by failure of the immune response to control the infection. Protective immune responses against intra-macrophage protozoa are usually mediated by T helper 1 (Th1) T cell responses. Here we examine the cytokine responses made by T. annulata-activated T cells. We show that the outcome of in vitro activation of T cells by parasitized macrophages is a skewing of their cytokine responses towards preferential expression of interferon-gamma (IFN-gamma) mRNA. The in vitro response is mirrored during in vivo infection, as greatly elevated amounts of IFN-gamma protein are found in lymph efferent from infected lymph nodes, while expression of IL-4 mRNA within the node stops. IFN-gamma production does not correlate with protection against the parasite, as infected cells flourish during peak IFN-gamma production, and only very small amounts of IFN-gamma are produced during the effective immune response of an immunized animal. Overproduction of IFN-gamma and loss of IL-4 expression are also likely to account for the failure of B cells to reach the light zone of germinal centres, a developmental step which is tightly regulated by cytokines.

Extrapleural suction buttress of primary esophageal repair

Buttress reinforcement of a primary esophageal repair after perforation may diminish the potential for breakdown or leakage of the approximation. We describe a method of reinforcing a primary esophageal repair by using pleural tissue that is secured in place with an extrapleural, soft T-tube attached to a suction device. This technique is simple to apply and may maximize recovery of respiratory function by permitting timely removal of chest tubes.