Corticosteroids as co-analgesics with opioids for cancer pain: a survey of Australian and New Zealand palliative care clinicians.

Corticosteroids are commonly used as co-analgesics with opioids for cancer pain; however limited quality data exist supporting their efficacy for this purpose. Further, little is known about individual prescribing practices. The current study surveyed members of the Australian New Zealand Society of Palliative Medicine about their use of corticosteroids as adjuvant analgesics in cancer pain. It confirmed high rates of utilisation and found variability in starting doses and associated decision-making. Further research is required to determine the efficacy and safety of corticosteroids as co-analgesics in cancer pain management.

Inpatient palliative care consultation for patients with glioblastoma in a tertiary hospital.

Glioblastoma (GBM) is an uncommon disease with significant mortality and morbidity, but there is a lack of published evidence on palliative care involvement with this population. This audit highlights the heavy symptom burden, extensive allied health involvement and discharge outcomes of GBM inpatients referred to the palliative care service at The Royal Melbourne Hospital. This information can provide an important framework for further research and also supports the role of multidisciplinary palliative care in the care of patients with GBM.

Correlation of serum protein biomarkers with disease activity in psoriatic arthritis.

Objective: To assess the correlation of serum protein biomarkers with disease activity across different domains of psoriatic arthritis (PsA).Material and methods: A cross-sectional cohort of 45 adult patients with PsA fulfilling the classification for psoriatic arthritis (CASPAR) criteria was recruited from University of California San Diego (UCSD) Arthritis Clinics. Clinical data and serum samples were collected and serum was analyzed for protein biomarkers hypothesized to be relevant to disease activity in PsA. Correlations were evaluated for clinical disease activity measures across disease domains.Results: Biomarkers with the highest correlation to the composite indices and disease domains were SAA, IL-6, YKL-40, and ICAM-1. In addition, several biomarkers were moderately correlated with individual composite indices and/or disease domains. Low or no correlation was observed with some biomarkers, e.g. MMP-3, MMP-1, EGF, VEGF, and IL-6R. In contrast, the correlation of all biomarkers with certain disease domains was low; specifically, pain, percent body surface area of psoriasis, and patient global assessment. The multi-biomarker disease activity score (MBDA) developed for rheumatoid arthritis (RA) showed high correlations with most composite indices and some disease domains in PsA.Conclusions: These data suggest biomarker analysis can reflect disease activity across disease domains in PsA. Certain domains would likely benefit from the evaluation of additional biomarkers.

Determination of the minimally important difference (MID) in multi-biomarker disease activity (MBDA) test scores: impact of diurnal and daily biomarker variation patterns on MBDA scores.

The Multi-Biomarker Disease Activity (MBDA) score is a validated rheumatoid arthritis (RA) disease activity measure based on 12 serum biomarkers. Here, we evaluate short-term biological variability of MBDA scores to determine the magnitude of change that might be considered clinically meaningful. Twenty-eight adult seropositive RA patients with clinically stable disease and no changes in RA medications for 4 weeks prior to study were enrolled. Nine serum samples were obtained over four consecutive days (non-fasting). MBDA score variation was assessed day-to-day (daily) and within 24 h (diurnal). The standard deviation (SD) of MBDA scores was calculated by a linear mixed model including random effects for patient, day, and time of day. The minimally important difference (MID) was calculated as [Formula: see text]. A subgroup analysis was performed for patients with active RA (moderate or high MBDA score). The SD of MBDA score change in the full cohort was 4.7 in a combined daily-diurnal variation analysis, which corresponds with an MID of 11. The SD of MBDA score change in the subset of patients with active RA (moderate/high MBDA scores) was 3.6. This corresponds with an MID of 8 units in patients with active RA for whom clinicians are most likely to need guidance with respect to therapeutic decisions. Changes in MBDA score ≥ 8 represent a change in RA disease activity that clinicians can use as a benchmark for therapeutic drug efficacy and can be incorporated into a treat-to-target strategy.

Protein dynamics simulations from nanoseconds to microseconds.

There have been a number of advances in atomic resolution simulations of biomolecules during the past few years. These have arisen partly from improvements to computer power and partly from algorithmic improvements. There have also been advances in measuring time-dependent fluctuations in proteins using NMR spectroscopy, revealing the importance of fluctuations in the microsecond to millisecond time range. Progress has also been made in measuring how far the simulations are able to represent the accessible phase space that is available to the protein in its native state, in solution, at room temperature. Another area of development is the simulation of protein unfolding at atomic resolution.

An evaluation of the performance of cDNA microarrays for detecting changes in global mRNA expression.

The cDNA microarray is one technological approach that has the potential to accurately measure changes in global mRNA expression levels. We report an assessment of an optimized cDNA microarray platform to generate accurate, precise and reliable data consistent with the objective of using microarrays as an acquisition platform to populate gene expression databases. The study design consisted of two independent evaluations with 70 arrays from two different manufactured lots and used three human tissue sources as samples: placenta, brain and heart. Overall signal response was linear over three orders of magnitude and the sensitivity for any element was estimated to be 2 pg mRNA. The calculated coefficient of variation for differential expression for all non-differentiated elements was 12-14% across the entire signal range and did not vary with array batch or tissue source. The minimum detectable fold change for differential expression was 1.4. Accuracy, in terms of bias (observed minus expected differential expression ratio), was less than 1 part in 10 000 for all non-differentiated elements. The results presented in this report demonstrate the reproducible performance of the cDNA microarray technology platform and the methods provide a useful framework for evaluating other technologies that monitor changes in global mRNA expression.

Selectively reduced expression of synaptic plasticity-related genes in amyloid precursor protein + presenilin-1 transgenic mice.

A critical question in Alzheimer's disease (AD) research is the cause of memory loss that leads to dementia. The amyloid precursor protein + presenilin-1 (APP+PS1) transgenic mouse is a model for amyloid deposition, and like AD, the mice develop memory deficits as amyloid deposits accumulate. We profiled gene expression in these transgenic mice by microarray and quantitative RT-PCR (qRT-PCR). At the age when these animals developed cognitive dysfunction, they had reduced mRNA expression of several genes essential for long-term potentiation and memory formation (Arc, Zif268, NR2B, GluR1, Homer-1a, Nur77/TR3). These changes appeared to be related to amyloid deposition, because mRNA expression was unchanged in the regions that did not accumulate amyloid. Transgene expression was similar in both amyloid-containing and amyloid-free regions of the brain. Interestingly, these changes occurred without apparent changes in synaptic structure, because a number of presynaptic marker mRNAs (growth-associated protein-43, synapsin, synaptophysin, synaptopodin, synaptotagmin, syntaxin) remained stable. Additionally, a number of genes related to inflammation were elevated in transgenic mice, primarily in the regions containing amyloid. In AD cortical tissue, the same memory-associated genes were downregulated. However, all synaptic and neuronal transcripts were reduced, implying that the loss of neurons and synapses contributed to these changes. We conclude that reduced expression of selected genes associated with memory consolidation are linked to memory loss in both circumstances. This suggests that the memory loss in APP+PS1 transgenic mice may model the early memory dysfunction in AD before the degeneration of synapses and neurons.

Fluorescence energy transfer indicates similar transient and equilibrium intermediates in staphylococcal nuclease folding.

Fluorescence resonance energy transfer (FRET) is one of the few methods available to measure the rate at which a folding protein collapses. Using staphylococcal nuclease in which a cysteine residue was engineered in place of Lys64, permitted FRET measurements of the distance between the donor tryptophan 140 and 5-[[2-[(iodoacetyl)-amino]ethyl]amino]naphthalene-1-sulfonic acid-labeled Cys64. These measurements were undertaken on both equilibrium partially folded intermediates at low pH (A states), as well as transient intermediates during stopped-flow refolding. The results indicate that there is an initial collapse of the protein in the deadtime of the stopped-flow instrument, corresponding to a regain of approximately 60% of the native signal, followed by three slower transients. This is in contrast to circular dichroism measurements which show only 20-25% regain of the native secondary structure in the burst phase. Thus hydrophobic collapse precedes the formation of substantial secondary structure. The first two detected transient intermediate species have FRET properties essentially identical with those of the previously characterized equilibrium A state intermediates, suggesting similar structures between the equilibrium and transient intermediates. The effects of anions on the folding of acid-unfolded staphylococcal nuclease, and urea on the unfolding of the resulting A states, indicates that in folding the protein becomes compact prior to formation of major secondary structure, whereas in unfolding the protein expands prior to major loss of secondary structure. Comparison of the kinetics of refolding of staphylococcal nuclease, monitored by FRET, and for a proline-free variant, indicate that folding occurs via two partially folded intermediates leading to a native-like species with one (or more) proline residues in a non-native conformation. For the A states an excellent correlation between compactness measured by FRET, and compactness determined from small-angle X-ray scattering, was observed. Further, a linear relationship between compactness and free energy of unfolding was noted. Formation of soluble aggregates of the A states led to dramatic enhancement of the FRET, consistent with intermolecular fluorescence energy transfer.

Minimal residual disease in interferon-treated chronic myelogenous leukemia: results and pitfalls of analysis based on polymerase chain reaction.

Therapy with interferon-alpha results in complete cytogenetic remission in 15-20% of patients with chronic myelogenous leukemia. Even during prolonged clinical follow-up, most of these patients do not relapse. However, because of the limited sensitivity of cytogenetic techniques (approximately 5%) and Southern blots (approximately 1%), it is uncertain whether the residual malignant clone becomes extinct or persists below the limit of detection in these patients. We used polymerase chain reaction to amplify the chimeric BCR-ABL transcripts in 18 patients with chronic myelogenous leukemia who became Ph1 chromosome negative while receiving treatment with interferon-alpha, either alone or in combination with interferon-gamma. At the time of study, these patients had been Ph1-negative for a median of 22+ months. Fifteen patients were positive for residual BCR-ABL transcripts. No residual BCR-ABL message was detected on analysis of multiple serial samples in three patients. In order to confirm these results, the samples from these three patients, along with positive and negative controls, were analyzed by two independent laboratories in a blinded fashion. In the first laboratory, RNA specimens from all three patients were considered negative using chemiluminescent acidinium-ester-labeled probes. In the second laboratory, samples from all three patients were also negative by conventional polymerase chain reaction (PCR). However, when a second round of amplification was carried out on the amplified samples using a different combination of primers, samples from two of the three patients were positive. The results confirm the presence of a small proportion of BCR-ABL-positive cells in the majority of patients who are in complete remission and highlight some of the potential problems of PCR-based analysis. There is a need to standardize PCR methodology and potential confounding factors need to be addressed before PCR can be generally applied to analysis of minimal residual disease in CML. The implications of BCR-ABL positivity for these patients are discussed.

Pre- and postsynaptic correlates of interocular competition and segregation in the frog.

Segregated zones of termination between converging inputs that arise from different presynaptic populations are a common property of topographically organized zones within the vertebrate central nervous system. Increasing evidence suggests that such segregation is at least in part established on the basis of competitive interactions that depend upon the activity patterns within each afferent population. However, the cellular mechanisms of these interactions are poorly understood. We have used a preparation in which a stereotyped interdigitating pattern of retina-specific termination stripes are produced in frog tecta innervated by two retinas as a result of embryonic implantation of a third eye primordia. In these animals it has been possible to examine the relationship between the number of retinal ganglion cells in each of the retinas innervating a striped tectum, the volumetric changes in the tectum as a result of this double innervation, and the pattern of eye-specific segregation that is produced. Counts of retinal ganglion cells in the retinas of the three-eyed frogs with one completely striped tectal lobe revealed no significant differences between cell numbers in the doubly innervating retinas and the normal retinas of the same animals. The average increase in retinal ganglion cell innervation to the striped tecta of these animals was 100%. However the tecta only increased in total volume by 26%. This later increase consisted of a 25% increase in the volume of the deep lying and predominantly cellular tectal laminae and a 37% increase in the superficial retinotectal synaptic zone. In many of these same animals HRP and 3H-proline were used to differentially label the set of stripes from each retina and measurements of the extent of each projection were performed. We found that the volume of tectal neuropil occupied by a striped projection is relatively unrelated to the number of ganglion cells making up that projection. Observations of the striping pattern after HRP processing to visualize stripes in whole unsectioned tecta indicate that the periodicities and rostrocaudal orientation of stripes are robust over a wide range of relative innervation densities. When one projection is much smaller than the other, stripes appear to break down into a series of "puffs" or islands of retina-specific termination zones. Nevertheless, these puffs still have a rostrocaudal alignment and the spacing of fully formed stripes. These observations suggest that the formation of exclusive termination zones may be a threshold phenomenon: so after a certain innervation density is reached one input can take over a unit of target neuropil in an all-or-none manner.(ABSTRACT TRUNCATED AT 400 WORDS)

Topographic and morphometric effects of bilateral embryonic eye removal on the optic tectum and nucleus isthmus of the leopard frog.

Rana pipiens were raised through metamorphosis after extirpation of both eye primordia at Shumway embryonic stage 17 (Shumway '40). The visual connections between the isthmic nuclei and the optic tectum were examined in these animals using horseradish peroxidase (HRP) histochemistry. Isthmo-tectal projections are normally aligned with the primary retinotectal map. We asked whether these connections would develop normal topographic organization in the absence of normal retinal input. HRP was formed into a solid pellet (congruent to 200-500 micrometer diameter) and inserted into one tectal lobe on the tip of a fine metal probe. The procedure produced relatively restricted retrograde label in somas and dendrites in both isthmi nuclei. In the nucleus isthmus ipsilateral to the tectal lobe receiving the HRP pellet, processes of tecto-isthmi neurons were labeled by anterograde transport. The topography of the isthmo-tectal and tecto-isthmic projections were identical in the developmentally enucleated animals and in normal frogs, even though eye removal severely reduced the volume of the optic tecta and the isthmi nuclei. Thus our analyses indicate that retinal contacts do not play an active role in the development of the positional or polarity cues that are involved in "mapping" projections between central visual nuclei. These results are discussed in the context of peripheral specification of central connections and in terms of models that have recently been proposed to explain the development of the retinotectal system.

Three-dimensional visualization and measurement of conformal dose distributions using magnetic resonance imaging of BANG polymer gel dosimeters.

PURPOSE/OBJECTIVE: The measurement of complex dose distributions (those created by irradiation through multiple beams, multiple sources, or multiple source dwell positions) requires a dosimeter that can integrate the dose during a complete treatment. Integrating dosimeter devices generally are capable of measuring only dose at a point (ion chamber, diode, TLD) or in a plane (film). With increasing use of conformal dose distributions requiring shaped, noncoplanar beams, there will be an increased requirement for a dosimeter that can record and display a 3D dose distribution. The use of a 3D dosimeter will be required to confirm the accuracy of treatment plans produced by the current generation of 3D treatment-planning computers. METHODS AND MATERIALS: The use of a Fricke-infused gel and magnetic resonance imaging (MRI) to demonstrate the localization of stereotactic beams has been demonstrated (11). The recently developed BANG polymer gel dosimetry system (MGS Research, Inc., Guilford, CT), based on radiation-induced chain polymerization of acrylic monomers dispersed in a tissue-equivalent gel, surpasses the Fricke-gel method by providing accurate, quantitative dose distribution data that do not deteriorate with time (6, 9). The improved BANG2 formulation contains 3% N,N'-methylene-bisacrylamide, 3% acrylic acid, 1% sodium hydroxide, 5% gelatin, and 88% water, where all percentages are by weight. The gel was poured into volumetric flasks, of dimensions comparable to a human head. The gels were irradiated with complex beam arrangements, similar to those used for conformal radiation therapy. Images of the gels were acquired using a Siemens 1.5T imager and a Hahn spin-echo pulse sequence (90 degrees-tau-180 degrees-tau-acquire, for different values of tau). The images were transferred via network to a Macintosh computer for which a data analysis and display program was written. The program calculates R2 maps on the basis of multiple TE images, using a monoexponential nonlinear least-squares fit based on the Levenberg-Marquardt algorithm. The program also creates a dose-to-R2 calibration function by fitting a polynomial to a set of dose and R2 data points, obtained from gels irradiated in test tubes to known doses. This function can then be applied to any other R2 map, so that a dose map can be computed and displayed. RESULTS: Through exposure to known doses of radiation, the gel has been shown to respond linearly with dose in the range of 0 to 10 Gy, and its response is independent of the beam energy or modality. Dose distributions have been imaged in orthogonal planes, and can be displayed in a convenient form for comparison with isodose plans. The response of the gel is stable; the gel can be irradiated at any time after its manufacture, and imaging can be conducted any time following a brief interval after irradiation. CONCLUSION: The polymer gel dosimeter has been shown to be a valuable device for displaying three-dimensional dose distributions. The imaged dose distribution can be compared easily with calculated dose distributions, to validate a treatment planning system. In the future, gels may be prepared in anthropomorphic phantoms, to confirm unique patient dose distributions.

Radiation therapy dosimetry using magnetic resonance imaging of polymer gels.

Further progress in the development of polymer gel dosimetry using MRI is reported, together with examples of its application to verify treatment plans for stereotactic radiosurgery and high dose rate brachytherapy. The dose distribution image produced in the tissue-equivalent gel by radiation-induced polymerization, and encoded in the spatial distribution of the NMR transverse relaxation rates (R2) of the water protons in the gel, is permanent. Maps of R2 are constructed from magnetic resonance imaging data and serve as a template for dose maps, which can be used to verify complex dose distributions from external sources or brachytherapy applicators. The integrating, three-dimensional, tissue-equivalent characteristics of polymer gels make it possible to obtain dose distributions not readily measured by conventional methods. An improved gel formulation (BANG-2) has a linear dose response that is independent of energy and dose rate for the situations studied to date. There is excellent agreement between the dose distributions predicted using treatment planning calculations and those measured using the gel method, and the clinical practical utility of MRI-based polymer gel dosimetry is thereby demonstrated.

Cerebellar hemangioblastoma with prominent stromal astrocytosis: diagnostic and histogenetic considerations.

A cerebellar hemangioblastoma with atypical radiologic and morphologic features is reported. On computed tomography this tumor presented as a single ring-enhancing mass in the right cerebellar hemisphere without adjacent cyst formation. It was radiologically indistinguishable from an abscess or malignant neoplasm. Postmortem examination demonstrated a circumscribed, cystic neoplasm arising in the pia at the base of a sulcus. Microscopically, the tumor contained a prominent astrocytic component that mimicked the appearance of a highly vascular astrocytoma. Hemangioblastomas with this degree of astrocytosis are unusual. They must be distinguished pathologically from both cystic astrocytoma and mixed hemangioblastoma-glioma (angioglioma).

Transitory acidification of semen as a potential method for the inactivation of some pathogenic microorganisms. Effect on fertilization and development of ova in superovulated heifers.

The fertilizing capacity of transitorily acidified semen was investigated with respect to using acidification as a method for destroying or inactivating acid labile pathogenic microorganisms in semen prior to freezing. Ejaculates diluted 1:1 with phosphate buffered saline (PBS) were acidified to pH 5.0 for 2 or 5 minutes before being returned to their original pH. They were then frozen by commercial methods and used to artificially inseminate superovulated heifers. A total 739 ova and embryos was collected from 119 inseminated donors. The fertilization rate was 88%, and 78% of the embryos were of transferable quality. Semen acidification had no apparent effect on the post-thaw percentage of intact acrosomes.

Pre-analytical effects of blood sampling and handling in quantitative immunoassays for rheumatoid arthritis.

Variability in pre-analytical blood sampling and handling can significantly impact results obtained in quantitative immunoassays. Understanding the impact of these variables is critical for accurate quantification and validation of biomarker measurements. Particularly, in the design and execution of large clinical trials, even small differences in sample processing and handling can have dramatic effects in analytical reliability, results interpretation, trial management and outcome. The effects of two common blood sampling methods (serum vs. plasma) and two widely-used serum handling methods (on the clot with ambient temperature shipping, "traditional", vs. centrifuged with cold chain shipping, "protocol") on protein and autoantibody concentrations were examined. Matched serum and plasma samples were collected from 32 rheumatoid arthritis (RA) patients representing a wide range of disease activity status. Additionally, a set of matched serum samples with two sample handling methods was collected. One tube was processed per manufacturer's instructions and shipped overnight on cold packs (protocol). The matched tube, without prior centrifugation, was simultaneously shipped overnight at ambient temperatures (traditional). Upon delivery, the traditional tube was centrifuged. All samples were subsequently aliquoted and frozen prior to analysis of protein and autoantibody biomarkers. Median correlation between paired serum and plasma across all autoantibody assays was 0.99 (0.98-1.00) with a median % difference of -3.3 (-7.5 to 6.0). In contrast, observed protein biomarker concentrations were significantly affected by sample types, with median correlation of 0.99 (0.33-1.00) and a median % difference of -10 (-55 to 23). When the two serum collection/handling methods were compared, the median correlation between paired samples for autoantibodies was 0.99 (0.91-1.00) with a median difference of 4%. In contrast, significant increases were observed in protein biomarker concentrations among certain biomarkers in samples processed with the 'traditional' method. Autoantibody quantification appears robust to both sample type (plasma vs. serum) and pre-analytical sample collection/handling methods (protocol vs. traditional). In contrast, for non-antibody protein biomarker concentrations, sample type had a significant impact; plasma samples generally exhibit decreased protein biomarker concentrations relative to serum. Similarly, sample handling significantly impacted the variability of protein biomarker concentrations. When biomarker concentrations are combined algorithmically into a single test score such as a multi-biomarker disease activity test for rheumatoid arthritis (MBDA), changes in protein biomarker concentrations may result in a bias of the score. These results illustrate the importance of characterizing pre-analytical methodology, sample type, sample processing and handling procedures for clinical testing in order to ensure test accuracy.

Characterization of a multiplex, 12-biomarker test for rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory disorder that primarily involves the joints. Accurate and frequent assessment of RA disease activity is critical to optimal treatment planning. A novel algorithm has been developed to determine a multi-biomarker disease activity (MBDA) score based upon measurement of the concentrations of 12 serum biomarkers in multiplex format. Biomarker assays from several different platforms were used in feasibility studies to identify biomarkers of potential significance. These assays were adapted to a multiplex platform for training and validation of the algorithm. In this study, the analytical performance of the underlying biomarker assays and the MBDA score was evaluated. Quantification of 12 biomarkers was performed with multiplexed sandwich immunoassays in three panels. Biomarker-specific capture antibodies were bound to specific locations in each well; detection antibodies were labeled with electrochemiluminescent tags. Data were acquired with a Sector Imager 6000, and analyte concentrations were determined. Parallelism, dynamic range, cross-reactivity, and precision were established for each biomarker as well as for the MBDA score. Interference by serum proteins, heterophilic antibodies, and common RA therapies was also assessed. The individual biomarker assays had 3-4 orders of magnitude dynamic ranges, with good reproducibility across time, operators, and reagent lots; the MBDA score had a median coefficient of variation of <2% across the score range. Cross-reactivity as well as interference by serum rheumatoid factor (RF), human anti-mouse antibodies (HAMA), or common RA therapies, including disease-modifying antirheumatic drugs and biologics, was minimal. The same MBDA score was observed in different subjects despite having different biomarker profiles, supporting prior literature reports that multiple pathways contribute to RA.