Practical problems with the collection and interpretation of serial quality of life assessments in patients with malignant glioma

Objectives: To assess the problems involved with the collection and interpretation of serial collected health related quality of life assessments in patients with malignant glioma. Patients and methods: One-hundred and fifty nine patients with malignant glioma from three Scottish neurosurgical centres in whom assessments of performance status, neurological impairment, mood, and quality of life had been recorded over a 6-month period were prospectively identified. The amount of missing data and the reasons for missing data were assessed. Characteristics of patients that were fully compliant with serial assessments were then compared with those that were not. Results: Compliance with serial assessments (both patient and observer reported) was poor, dropping to less than 50% at 6 months. Observer reported measures showed a similar pattern of decline as patient reported measures. The largest single cause of missing data (approximately 70%) was due to administrative failure. Compliant patients were found to have a significantly greater probability of survival compared to non-compliant patients and were also found to be younger and fitter relative to the rest of the study population. Conclusions: Studies utilising quality of life outcomes should give early consideration to minimising avoidable sources of missing data and recording the reasons for non-compliance. Quality of life studies basing conclusions on a complete case analysis should be wary of possible bias.     

Parathyroid carcinoma: is there a role for adjuvant radiation therapy?

BACKGROUND: The authors proposed to determine risk factors associated with postoperative progression of parathyroid carcinoma within the neck (locoregional) and to assess the efficacy of postoperative adjuvant radiation therapy in preventing disease progression within the neck. METHODS: A retrospective review of patients with pathologically confirmed parathyroid carcinoma who underwent surgical resection was performed. Risk factors identified on univariate analysis were applied in a proportional hazards analysis to identify significant independent predictors of locoregional disease progression and cause-specific survival after surgical resection. Fifty-seven patients were treated with surgery alone (no adjuvant radiation therapy [RT]) and were determined to have sufficient follow-up and pathologically confirmed features to be included in the current analysis. Four patients were treated with surgery and adjuvant RT. Four patients received RT to the neck and mediastinum for unresectable locoregional disease progression. Patients were followed for a median of 75.6 months (range, 8.4-358 months). RESULTS: Twenty-five patients (44%) developed locoregional disease progression at a median of 27.1 months after surgery (range, 6.2-138.3 months). The univariate analysis revealed that surgical margin status and the institution at which the initial surgery was performed were predictive of locoregional progression-free survival. The institution at which the initial surgery was performed was found to be an independent predictor of cause-specific survival. Of the four patients treated with surgery and adjuvant RT, all were alive and without disease at the time of last follow-up. All four patients who received RT for locoregional disease progression after initial surgery achieved locoregional disease control. CONCLUSIONS: Patients with parathyroid carcinoma are reported to have a significant risk of locoregional disease progression after surgery alone. The results of the current study demonstrated that the risk of postoperative disease progression can be predicted by surgical margin status and the institution at which the initial surgery is performed. Patients treated with surgery and postoperative RT may have a lower risk of locoregional disease progression and improved cause-specific survival. RT can be used to provide locoregional control of recurrent disease.     

Low back pain in Australian adults: the economic burden

This paper reports the results of a "cost-of-illness" study of low back pain (LBP) in Australian adults. It estimates the direct cost of LBP in 2001 to be AU dollars 1.02 billion. Approximately 71% of this amount is for treatment by chiropractors, general practitioners, massage therapists, physiotherapists and acupuncturists. However, the direct costs are minor compared to the indirect costs of AU dollars 8.15 billion giving a total cost of AU dollars 9.17 billion. LBP in Australian adults represents a massive health problem with a significant economic burden. This burden is so great that it has compelling and urgent ramifications for health policy, planning and research. This study identifies that research should concentrate on both direct but particularly the indirect costs including cost-effective management regimes that encourage an early return to duties.     

Aseptic meningitis epidemic during a West Nile virus avian epizootic

While enteroviruses have been the most commonly identified cause of aseptic meningitis in the United States, the role of the emerging, neurotropic West Nile virus (WNV) is not clear. In summer 2001, an aseptic meningitis epidemic occurring in an area of a WNV epizootic in Baltimore, Maryland, was investigated to determine the relative contributions of WNV and enteroviruses. A total of 113 aseptic meningitis cases with onsets from June 1 to September 30, 2001, were identified at six hospitals. WNV immunoglobulin M tests were negative for 69 patients with available specimens; however, 43 (61%) of 70 patients tested enterovirus-positive by viral culture or polymerase chain reaction. Most (76%) of the serotyped enteroviruses were echoviruses 13 and 18. Enteroviruses, including previously rarely detected echoviruses, likely caused most aseptic meningitis cases in this epidemic. No WNV meningitis cases were identified. Even in areas of WNV epizootics, enteroviruses continue to be important causative agents of aseptic meningitis.     

Developing a departmental culture for reporting adverse incidents

A simple, reproducible model for reporting adverse events was developed in order to promote cultural awareness and acceptance of risk management within the authors' department. A departmental proforma was created and prospective reporting of adverse events was encouraged. In the six months prior to commencing this study only four adverse incidents were reported. Following the introduction of the proforma 64 critical incidents and near-misses were reported in the one-year period. In conclusion a simple model for reporting critical incidents and near-misses has been established. This has fostered a cultural change within the department and all members of staff feel more comfortable with reporting such incidents. The process is seen as educational and an important part of continuing professional and departmental development. Protocols and changes in organisational practice have been developed to reduce and prevent the occurrence of adverse events and offer patients continuous improvement in care.     

Inhibition of indoleamine 2,3-dioxygenase activity in IFN-gamma stimulated astroglioma cells decreases intracellular NAD levels

Astroglia provide essential metabolic and neurotropic support to cells within the CNS and participate in the cellular immune response with microglia/macrophages following activation by the pro-inflammatory cytokine IFN-gamma. Activation of glial cells results in local oxidative stress and induction of a number of proteins including the enzyme indoleamine 2,3-dioxygenase (IDO). As a rate-limiting enzyme, IDO regulates tryptophan catabolism via the kynurenine pathway producing a series of metabolic precursors (some of which are neurotoxic) before complete oxidation to the essential pyridine nucleotide NAD. Inhibition of this pathway may therefore prove therapeutic in neuroinflammatory disease by reducing production of cell toxins. However, kynurenine metabolism may also be cytoprotective through de novo synthesis of cellular NAD levels. We investigated the hypothesis that IDO activity is directly involved in maintenance of intracellular [NAD] in activated astroglial cells through control of de novo synthesis. Exposure to IFN-gamma increased IDO activity from 7+/-1 nmol to 129+/-11 nmol kynurenine/hr/mg protein. Inhibition of IDO activity with either 6-chloro-D-tryptophan (competitive inhibition), or 3-ethoxy beta-carboline (non-competitive inhibition) resulted in a dose-dependent decrease in IDO activity that correlated directly with decreasing [NAD] (R(2)=0.92 and 0.81, respectively). These results support the hypothesis that one important consequence of increasing IDO activity in astroglial cells during inflammation is to maintain NAD levels through de novo synthesis from tryptophan. Inhibition of kynurenine pathway metabolism under these conditions may significantly decrease cell viability and CNS functions unless alternate precursors for NAD synthesis are available.     

Enforced expression of the tumor suppressor p53 renders human leukemia cells (U937) more sensitive to 1-[beta-D-arabinofuranosyl]cytosine (ara-C)-induced apoptosis

The effects of enforced expression of p53 on the sensitivity of p53(-/-) human monocytic leukemia cells (U937) to apoptosis following exposure to the S-phase-specific antimetabolite 1-[beta-D-arabinofuranosyl]cytosine (ara-C) were examined. Cells were stably transfected with a plasmid containing a chimeric DNA construct encoding a temperature-sensitive p53 variant (135(ala-->val)), which transactivates at 32 degrees but is non-functional at 37 degrees. A significant reduction in the S-phase population was observed in ptsp53 mutants incubated at 32 degrees. Nevertheless, while vector controls did not exhibit differential sensitivity to ara-C at 32 degrees versus 37 degrees, temperature-sensitive p53 mutants displayed a significant increase in apoptosis at the permissive temperature. This was not accompanied by increased ara-CTP formation, DNA incorporation of [3H]ara-C, or altered expression of Bcl-2 or Bax. Enhanced sensitivity was associated with increased mitochondrial injury (e.g. cytochrome c release), caspase activation, and loss of clonogenic survival. Significantly, ptsp53 cells synchronized in S phase were markedly more sensitive to ara-C-mediated mitochondrial injury and apoptosis at 32 degrees, indicating that wild-type p53 specifically enhances the susceptibility of this subpopulation to ara-C lethality. Consistent with these results, transient transfection of human wild-type p53 cDNA rendered parental U937 cells more sensitive to ara-C-mediated cell death. Collectively, these findings indicate that p53 expression renders S-phase U937 cells more susceptible to ara-C-mediated mitochondrial dysfunction, cytochrome c release, apoptosis, and loss of clonogenic survival without enhancing ara-C metabolism. Such findings raise the possibility that loss of functional p53 activity allows leukemia cells to circumvent ara-C lethality.     

Analgesic duration and kinetics of liposomal bupivacaine after subcutaneous injection in mice

1. The objective of the present study was to assess the time-course profile of analgesia and bupivacaine concentrations at the site of injection after subcutaneous administration of a single dose of standard bupivacaine or a novel controlled-release liposomal bupivacaine formulation. 2. Groups of mice were injected subcutaneously with 0.2 mL of 0.5% standard bupivacaine or 0.5, 1 or 2% liposomal bupivacaine. 3. A prolonged duration of analgesia occurred in mice receiving liposomal bupivacaine. In the liposomal groups, the bupivacaine remained at the injection site for more than 96 h, compared with approximately 8 h in groups injected with standard bupivacaine. 4. These results confirm that the prolonged analgesia observed after injection of the liposomal formulation is associated with sustained higher levels of bupivacaine at the site of injection.     

mda-7 (IL-24) Inhibits growth and enhances radiosensitivity of glioma cells in vitro via JNK signaling

Despite therapeutic interventions including surgery, chemotherapy and radiotherapy, glioblastoma multiforme (GBM) has a very poor prognosis and novel therapies are required. MDA-7 (IL-24), when expressed via a recombinant replication defective adenovirus, Ad.mda-7, has profound anti-proliferative and cytotoxic effects in a variety of tumor cells, but not in non-transformed cells. The present studies examined the combined impact of Ad.mda-7 and ionizing radiation on the proliferation and survival of GBM cells. Ad.mda-7 reduced the proliferation of rodent and human glioma cells in MTT assays and in colony formation assays. The anti-proliferative effects of Admda-7 were enhanced by radiation in a greater than additive fashion. In vitro, this cellular change correlated with enhanced cell numbers in G1/G0 and G2/M phases of the cell cycle, implying Ad.mda-7 radiosensitizes tumor cells in a cell cycle-independent manner. The radiosensitizing effects were not observed in cultures of non-transformed primary astrocytes. The enhanced reduction in growth correlated with increased necrosis and DNA degradation. Ad.mda-7 enhanced p38 and ERK1/2 activity but did not alter JNK or Akt activity. Irradiation of cells expressing MDA-7 suppressed ERK1/2 activity and dramatically enhanced JNK1/2 activity without altering either Akt or p38 activity. Inhibition of JNK1/2, but not p38, signaling abolished the radiosensitizing properties of MDA-7. Inhibition of neither ERK1/2 nor PI3K signaling enhanced the anti-proliferative effects of Ad.mda-7, whereas combined inhibition of both pathways enhanced cell killing, suggesting that ERK and PI3K signaling can be protective against MDA-7 lethality.     

Histone deacetylase inhibitors in cancer therapy

Histone deacetylase inhibitors (HDAC inhibitors) represent a novel class of antineoplastic agents that act by promoting acetylation of histones, leading in turn to uncoiling of chromatin and activation of a variety of genes implicated in the regulation of cell surivival, proliferation, differentiation, and apoptosis. The major classes of HDIs include shortchain fatty acids, hydroxamic acid derivatives, synthetic benzamide derivatives, and cyclic tetrapeptides. Members of each of these classes have now entered clinical trials in humans. Despite their shared capacity to trigger histone deacetylation, individual HDIs exert diverse actions on cell cycle regulatory, signal transduction, and survival-related proteins which in all probability accounts for their disparate actions. Major areas of investigation surrounding HDIs include elucidating the mechanisms by which they induce apoptosis in neoplastic cells, and characterizing the factors responsible for the decision of such cells to undergo maturation versus cell death in the response to these agents. In this context, attention has recently focused on the ability of HDIs to induce perturbations in cell cycle regulatory proteins (e.g., p21(CIP1)), downregulation of survival signaling pathways (e.g., Raf/MEK/ERK), and disruption of cellular redox state (e.g., induction of reactive oxygen species; ROS). Aside from efforts to combine HDIs with established cytotoxic drugs, attempts are underway to establish a rational basis for combining HDIs with differentiation- inducing agents (e.g., ATRA, hypomethylating agents such as 5'-deoxyazacytine) with the goal of triggering re-expression of turn or suppressor and/or differentiation-associated genes. Finally, the results of recent preclinical studies provide a strong rationale for combining HDIs with other novel, molecularly targeted agents, including inhibitors of survival signaling pathways or cell cycle progression. Collectively, these findings should provide a fertile environment for the development of novel HDI-containing regimens in the treatment of cancer for many years to come.