A magneto-activated nanoscale cytometry platform for molecular profiling of small extracellular vesicles

Exosomal PD-L1 (exoPD-L1) has recently received significant attention as a biomarker predicting immunotherapeutic responses involving the PD1/PD-L1 pathway. However, current technologies for exosomal analysis rely primarily on bulk measurements that do not consider the heterogeneity found within exosomal subpopulations. Here, we present a nanoscale cytometry platform NanoEPIC, enabling phenotypic sorting and exoPD-L1 profiling from blood plasma. We highlight the efficacy of NanoEPIC in monitoring anti-PD-1 immunotherapy through the interrogation of exoPD-L1. NanoEPIC generates signature exoPD-L1 patterns in responders and non-responders. In mice treated with PD1-targeted immunotherapy, exoPD-L1 is correlated with tumor growth, PD-L1 burden in tumors, and the immune suppression of CD8+ tumor-infiltrating lymphocytes. Small extracellular vesicles (sEVs) with different PD-L1 expression levels display distinctive inhibitory effects on CD8 + T cells. NanoEPIC offers robust, high-throughput profiling of exosomal markers, enabling sEV subpopulation analysis. This platform holds the potential for enhanced cancer screening, personalized treatment, and therapeutic response monitoring.

Multi-campaign ship and aircraft observations of marine cloud condensation nuclei and droplet concentrations

In-situ marine cloud droplet number concentrations (CDNCs), cloud condensation nuclei (CCN), and CCN proxies, based on particle sizes and optical properties, are accumulated from seven field campaigns: ACTIVATE; NAAMES; CAMP2EX; ORACLES; SOCRATES; MARCUS; and CAPRICORN2. Each campaign involves aircraft measurements, ship-based measurements, or both. Measurements collected over the North and Central Atlantic, Indo-Pacific, and Southern Oceans, represent a range of clean to polluted conditions in various climate regimes. With the extensive range of environmental conditions sampled, this data collection is ideal for testing satellite remote detection methods of CDNC and CCN in marine environments. Remote measurement methods are vital to expanding the available data in these difficult-to-reach regions of the Earth and improving our understanding of aerosol-cloud interactions. The data collection includes particle composition and continental tracers to identify potential contributing CCN sources. Several of these campaigns include High Spectral Resolution Lidar (HSRL) and polarimetric imaging measurements and retrievals that will be the basis for the next generation of space-based remote sensors and, thus, can be utilized as satellite surrogates.

Harmonized and high-quality datasets of aerosol optical depth at a US continental site, 1997-2018

Aerosol optical depth (AOD) characterizes the aerosol burden in the atmosphere, while its wavelength dependence is a sign of particle size. Long-term records of wavelength-resolved AOD with high quality and suitable continuity are required for climate change assessment. Typically, climate-related studies use AOD products provided by several, and perhaps different, ground-based instruments. The measurements from these instruments often have different accuracy and temporal resolution. To preserve the advantages of these products (high quality) and to reduce their disadvantages (patchy records), we generate a merged dataset obtained from four instruments deployed at a US continental site in which a nearly-continuous AOD record is found at two wavelengths (500 and 870 nm) with high quality and high temporal resolution (1-min) for a 21-yr period (1997-2018). The combined dataset addresses: (1) varying data quality and resolution mismatch of the individual AOD records, and (2) the uncertainty of the merged AOD and its relevance for user-specified needs. The generated dataset will be beneficial for a wide range of applications including aerosol-radiation interactions.

Lyme Disease Biosensors: A Potential Solution to a Diagnostic Dilemma

Over the past four decades, Lyme disease has remained a virulent and pervasive illness, persisting throughout North America and many other regions of the world. Recent increases in illness in many countries has sparked a renewed interest in improved Lyme diagnostics. While current standards of diagnosis are acceptable for the late stages of the disease, it remains difficult to accurately diagnose early forms of the illness. In addition, current diagnostic methods tend to be relatively expensive and require a large degree of laboratory-based analysis. Biosensors represent the fusion of biological materials with chemical techniques to provide simple, inexpensive alternatives to traditional diagnostic methods. Lyme disease biosensors have the potential to better diagnose early stages of the illness and provide possible patients with an inexpensive, commercially available test. This review examines the current state of Lyme disease biosensing, with a focus on previous biosensor development and essential future considerations.

Photolysis Controls Atmospheric Budgets of Biogenic Secondary Organic Aerosol

Secondary organic aerosol (SOA) accounts for a large fraction of the tropospheric particulate matter. Although SOA production rates and mechanisms have been extensively investigated, loss pathways remain uncertain. Most large-scale chemistry and transport models account for mechanical deposition of SOA but not chemical losses such as photolysis. There is also a paucity of laboratory measurements of SOA photolysis, which limits how well photolytic losses can be modeled. Here, we show, through a combined experimental and modeling approach, that photolytic loss of SOA mass significantly alters SOA budget predictions. Using environmental chamber experiments at variable relative humidity between 0 and 60%, we find that SOA produced from several biogenic volatile organic compounds undergoes photolysis-induced mass loss at rates between 0 and 2.2 ± 0.4% of nitrogen dioxide (NO₂) photolysis, equivalent to average atmospheric lifetimes as short as 10 h. We incorporate our photolysis rates into a regional chemical transport model to test the sensitivity of predicted SOA mass concentrations to photolytic losses. The addition of photolysis causes a ∼50% reduction in biogenic SOA loadings over the Amazon, indicating that photolysis exerts a substantial control over the atmospheric SOA lifetime, with a likely dependence upon the SOA molecular composition and thus production mechanisms.

Lense-Thirring frame dragging induced by a fast-rotating white dwarf in a binary pulsar system

Radio pulsars in short-period eccentric binary orbits can be used to study both gravitational dynamics and binary evolution. The binary system containing PSR J1141-6545 includes a massive white dwarf (WD) companion that formed before the gravitationally bound young radio pulsar. We observed a temporal evolution of the orbital inclination of this pulsar that we infer is caused by a combination of a Newtonian quadrupole moment and Lense-Thirring (LT) precession of the orbit resulting from rapid rotation of the WD. LT precession, an effect of relativistic frame dragging, is a prediction of general relativity. This detection is consistent with an evolutionary scenario in which the WD accreted matter from the pulsar progenitor, spinning up the WD to a period of <200 seconds.

A single fast radio burst localized to a massive galaxy at cosmological distance

Fast radio bursts (FRBs) are brief radio emissions from distant astronomical sources. Some are known to repeat, but most are single bursts. Nonrepeating FRB observations have had insufficient positional accuracy to localize them to an individual host galaxy. We report the interferometric localization of the single-pulse FRB 180924 to a position 4 kiloparsecs from the center of a luminous galaxy at redshift 0.3214. The burst has not been observed to repeat. The properties of the burst and its host are markedly different from those of the only other accurately localized FRB source. The integrated electron column density along the line of sight closely matches models of the intergalactic medium, indicating that some FRBs are clean probes of the baryonic component of the cosmic web.

The magnetic field and turbulence of the cosmic web measured using a brilliant fast radio burst

Fast radio bursts (FRBs) are millisecond-duration events thought to originate beyond the Milky Way galaxy. Uncertainty surrounding the burst sources, and their propagation through intervening plasma, has limited their use as cosmological probes. We report on a mildly dispersed (dispersion measure 266.5 ± 0.1 parsecs per cubic centimeter), exceptionally intense (120 ± 30 janskys), linearly polarized, scintillating burst (FRB 150807) that we directly localize to 9 square arc minutes. On the basis of a low Faraday rotation (12.0 ± 0.7 radians per square meter), we infer negligible magnetization in the circum-burst plasma and constrain the net magnetization of the cosmic web along this sightline to <21 nanogauss, parallel to the line-of-sight. The burst scintillation suggests weak turbulence in the ionized intergalactic medium.

The host galaxy of a fast radio burst

In recent years, millisecond-duration radio signals originating in distant galaxies appear to have been discovered in the so-called fast radio bursts. These signals are dispersed according to a precise physical law and this dispersion is a key observable quantity, which, in tandem with a redshift measurement, can be used for fundamental physical investigations. Every fast radio burst has a dispersion measurement, but none before now have had a redshift measurement, because of the difficulty in pinpointing their celestial coordinates. Here we report the discovery of a fast radio burst and the identification of a fading radio transient lasting ~6 days after the event, which we use to identify the host galaxy; we measure the galaxy's redshift to be z = 0.492 ± 0.008. The dispersion measure and redshift, in combination, provide a direct measurement of the cosmic density of ionized baryons in the intergalactic medium of ΩIGM = 4.9 ± 1.3 per cent, in agreement with the expectation from the Wilkinson Microwave Anisotropy Probe, and including all of the so-called 'missing baryons'. The ~6-day radio transient is largely consistent with the radio afterglow of a short γ-ray burst, and its existence and timescale do not support progenitor models such as giant pulses from pulsars, and supernovae. This contrasts with the interpretation of another recently discovered fast radio burst, suggesting that there are at least two classes of bursts.

Variation in Arterial Access for Invasive Coronary Procedures in New Zealand: A National Analysis (ANZACS-QI 5)

BACKGROUND

Radial arterial access (RA) and femoral arterial access (FA) rates for invasive coronary angiography (ICA) vary widely internationally. The European Society of Cardiology (ESC) suggests default RA is feasible. We aim to investigate the variation in RA rates across all New Zealand public hospitals.

METHODS AND RESULTS

Patient characteristics, procedural details, and inpatient outcome data were collected in the All New Zealand Acute Coronary Syndrome - Quality Improvement (ANZACS-QI) registry on consecutive patients undergoing ICA over five months. Of the 5894 ICAs 81% were via RA. Hospitals averaged 25 - 176 procedures/month (46.5% - 96.4% via RA). Operators averaged 17 procedures/month. Those performing more than 20 ICAs/month had RA rates between 61% - 99%. Of the 75 operators, 69% met the ESC recommendation. After multivariable adjustment higher operator (RR 1.12, CI 1.09 - 1.30) and hospital (RR 1.21, CI 1.15 - 1.28) volume were independent predictors of RA. Those with prior CABG (RR 0.51, CI 0.45 - 0.57), STEMI <12h (RR 0.91, CI 0.87 - 0.96), and female sex (RR 0.96, CI 0.94 - 0.99) were less likely to receive RA.

CONCLUSIONS

New Zealand has a high RA rate for ICAs. Rates vary substantially between both operators and centres. Radial arterial was highest amongst the highest volume operators and centres.

Early HIV Infections Among Men Who Have Sex with Men in Five Cities in the United States

We tested blood samples from men who have sex with men (MSM) to detect early HIV infection. Early HIV included both acute (infected past 30 days) and recent (estimated recency past 240 days). Acute infections were defined as screen immunoassay (IA) negative/NAAT-positive or IA-positive/Multispot-negative/NAAT-positive. Recent infections were defined as avidity index cutoff <30 % on an avidity-based IA and, (1) not reporting antiretroviral therapy use or, (2) HIV RNA >150 copies/mL. Of 937 samples, 26 % (244) were HIV-infected and of these 5 % (12) were early. Of early infections, 2 were acute and 10 recent; most (8/12) were among black MSM. Early infection was associated with last partner of black race [adjusted relative risk (ARR) = 4.6, confidence intervals (CI) 1.2-17.3], receptive anal sex at last sex (ARR = 4.3, CI 1.2-15.0), and daily Internet use to meet partners/friends (ARR = 3.3, CI 1.1-9.7). Expanding prevention and treatment for black MSM will be necessary for reducing incidence in the United States.

Shape-morphing nanocomposite origami

Nature provides a vast array of solid materials that repeatedly and reversibly transform in shape in response to environmental variations. This property is essential, for example, for new energy-saving technologies, efficient collection of solar radiation, and thermal management. Here we report a similar shape-morphing mechanism using differential swelling of hydrophilic polyelectrolyte multilayer inkjets deposited on an LBL carbon nanotube (CNT) composite. The out-of-plane deflection can be precisely controlled, as predicted by theoretical analysis. We also demonstrate a controlled and stimuli-responsive twisting motion on a spiral-shaped LBL nanocomposite. By mimicking the motions achieved in nature, this method offers new opportunities for the design and fabrication of functional stimuli-responsive shape-morphing nanoscale and microscale structures for a variety of applications.

A review of the volatiles from the healthy human body

A compendium of all the volatile organic compounds (VOCs) emanating from the human body (the volatolome) is for the first time reported. 1840 VOCs have been assigned from breath (872), saliva (359), blood (154), milk (256), skin secretions (532) urine (279), and faeces (381) in apparently healthy individuals. Compounds were assigned CAS registry numbers and named according to a common convention where possible. The compounds have been grouped into tables according to their chemical class or functionality to permit easy comparison. Some clear differences are observed, for instance, a lack of esters in urine with a high number in faeces. Careful use of the database is needed. The numbers may not be a true reflection of the actual VOCs present from each bodily excretion. The lack of a compound could be due to the techniques used or reflect the intensity of effort e.g. there are few publications on VOCs from blood compared to a large number on VOCs in breath. The large number of volatiles reported from skin is partly due to the methodologies used, e.g. collecting excretions on glass beads and then heating to desorb VOCs. All compounds have been included as reported (unless there was a clear discrepancy between name and chemical structure), but there may be some mistaken assignations arising from the original publications, particularly for isomers. It is the authors' intention that this database will not only be a useful database of VOCs listed in the literature, but will stimulate further study of VOCs from healthy individuals. Establishing a list of volatiles emanating from healthy individuals and increased understanding of VOC metabolic pathways is an important step for differentiating between diseases using VOCs.

Integrating molecular diagnostics into histopathology training: the Belfast model

Molecular medicine is transforming modern clinical practice, from diagnostics to therapeutics. Discoveries in research are being incorporated into the clinical setting with increasing rapidity. This transformation is also deeply changing the way we practise pathology. The great advances in cell and molecular biology which have accelerated our understanding of the pathogenesis of solid tumours have been embraced with variable degrees of enthusiasm by diverse medical professional specialties. While histopathologists have not been prompt to adopt molecular diagnostics to date, the need to incorporate molecular pathology into the training of future histopathologists is imperative. Our goal is to create, within an existing 5-year histopathology training curriculum, the structure for formal substantial teaching of molecular diagnostics. This specialist training has two main goals: (1) to equip future practising histopathologists with basic knowledge of molecular diagnostics and (2) to create the option for those interested in a subspecialty experience in tissue molecular diagnostics to pursue this training. It is our belief that this training will help to maintain in future the role of the pathologist at the centre of patient care as the integrator of clinical, morphological and molecular information.

A review of the volatiles from the healthy human body

A compendium of all the volatile organic compounds (VOCs) emanating from the human body (the volatolome) is for the first time reported. 1840 VOCs have been assigned from breath (872), saliva (359), blood (154), milk (256), skin secretions (532) urine (279), and faeces (381) in apparently healthy individuals. Compounds were assigned CAS registry numbers and named according to a common convention where possible. The compounds have been grouped into tables according to their chemical class or functionality to permit easy comparison. Some clear differences are observed, for instance, a lack of esters in urine with a high number in faeces. Careful use of the database is needed. The numbers may not be a true reflection of the actual VOCs present from each bodily excretion. The lack of a compound could be due to the techniques used or reflect the intensity of effort e.g. there are few publications on VOCs from blood compared to a large number on VOCs in breath. The large number of volatiles reported from skin is partly due to the methodologies used, e.g. collecting excretions on glass beads and then heating to desorb VOCs. All compounds have been included as reported (unless there was a clear discrepancy between name and chemical structure), but there may be some mistaken assignations arising from the original publications, particularly for isomers. It is the authors' intention that this database will not only be a useful database of VOCs listed in the literature, but will stimulate further study of VOCs from healthy individuals. Establishing a list of volatiles emanating from healthy individuals and increased understanding of VOC metabolic pathways is an important step for differentiating between diseases using VOCs.

Imaging findings in recurrent extramedullary leukaemias

Acute leukaemias are relatively common malignancies. Treatment has advanced significantly in the recent past and there has been improved patient survival. This improved initial response is leading to an increasing number of cases of relapse. Extramedullary relapse occurs in a wide variety of locations with varying presentations, imaging findings and differentials. The pathophysiology and clinical course of recurrent extramedullary myeloid and lymphocytic leukaemias are reviewed in this article. The wide variety of imaging findings associated with many important sites of recurrence and the associated differential diagnosis are discussed and illustrated.

Growing pains: twin family study evidence for genetic susceptibility and a genetic relationship with restless legs syndrome

BACKGROUND

Growing pains (GP) is a prevalent familial childhood disorder of unknown aetiology. Familial occurrence of GP, and individual and familial association of GP with restless legs syndrome (RLS) has been reported.

METHODS

We applied a twin family design to search for evidence of genetic susceptibility to GP, and for a genetic relationship between GP and RLS. The parents of 1843 twin pairs aged 3-16 years were administered a questionnaire, which identified 88 pairs with at least one twin individual fulfilling criteria for GP. Standard questionnaires for history of GP and RLS were completed for these twin pairs, their siblings and parents.

RESULTS

Twenty-five of 34 monozygotic (MZ) pairs were concordant for GP, compared with 12 of the 54 dizygotic (DZ) pairs. The casewise concordance was 0.85 and 0.36 for MZ and DZ pairs, respectively (p < 0.001). The lifetime GP prevalence for relatives of twins with GP was 51% for non-twin siblings, 47% for parents. Twenty-three percent of twin individuals with GP met RLS criteria compared with 8% of twin individuals without GP (p = 0.03). Of the twins with GP concordance, 19% met RLS criteria compared with 2% of twins with GP discordance (p = 0.01). In two MZ pairs, one had GP and the other RLS. The lifetime prevalence of RLS was 40% for mothers, and 24% for fathers and 18% for non-twin siblings.

CONCLUSION

This first twin family study of GP provides evidence for a genetic aetiology and for a genetic relationship to RLS.

P3-05-08: Hormone Receptor Heterogeneity in Ductal Intraepithelial Neoplasia (Ductal Carcinoma In Situ) of the Breast

Background: Ductal Intraepithelial Neoplasia [DIN] often shows heterogeneity of both morphology and nuclear grade within the same patient. It is unknown whether this implies heterogeneity with respect to hormone receptor status that may affect treatment. We sought to determine the rate of heterogeneity in terms of nuclear grade and receptor status in DIN patients.

Methods: A hospital tumor registry was queried for patients diagnosed with DIN between 1980 and 2010. Of the 746 patients identified, 579 (77.6%) had a concomitant invasive tumor. Of the remaining 167 patients, 70 were diagnosed prior to 2007 (when ASCO-CAP guidelines for hormone receptor measurements were released), 2 were found to have lobular intraepithelial neoplasia rather than DIN, and in 11 cases, pathology slides were not available for review. Of the 84 remaining patients with DIN, 17 (20.2%) had DIN 1 alone, 19 (22.6%) had DIN 2 alone, and 7 (8.3%) had DIN 3 alone. 41 (48.8%) of the patients had more than one grade of DIN. These patients formed the cohort of interest. Slides were reviewed by a single pathologist who evaluated ER and PR positivity within the different grades of DIN in each patient, classifying tumors staining 1% or greater as positive. Statistical analyses were performed using SPSS.

Results: The median patient age was 53 years old. Of the 41 patients with multiple grades of DIN, 32 (78.0%) had DIN 1 and 2, 6 (14.6%) had DIN 2 and 3, and 3 (7.3%) had DIN 1, 2, and 3 within the same tumor. 93.8%, 94.7% and 88.9% of DIN 1, 2 and 3 lesions respectively were ER-positive. A difference in hormone receptor status between different grades of DIN within the same tumor was noted in 12 (29.3%) of patients; of these 3 (10.3%) varied in ER status and 10 (34.5%) varied in PR status. Of the 2 patients with ER-negative DIN 1, both had ER-positive higher grade DIN within the same tumor. Of the 2 patients with ER-negative DIN 2, one had ER-positive DIN 1 while the other had ER-negative DIN 3. Therefore, of the total 41 patients, 40 (97.6%) had at least one component of DIN that was ER-positive, and evaluating more than one grade of DIN for ER allowed 75% of patients with at least one ER-negative component to be offered hormonal therapy.

Conclusions: Nearly 50% of patients with DIN will have more than one nuclear grade in the same tumor. These different nuclear grades vary in hormone receptor status in approximately 30% of patients. The majority of patients (97.6%) have at least one component of their DIN that is ER-positive. For those who have at least one component that is ER-negative, up to 75% may be offered hormonal therapy by considering other grades of DIN in treatment decision-making.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-05-08.

Effects of boron doping on the structural and optical properties of silicon nanocrystals in a silicon dioxide matrix

Doping of Si nanocrystals is an important topic in the emerging field of Si nanocrystals based all-Si tandem solar cells. Boron-doped Si nanocrystals embedded in a silicon dioxide matrix were realized by a co-sputtering process, followed by high temperature annealing. The x-ray photoelectron spectroscopy B 1s signal attributable to Si-B (187 eV) and/or B-B (188 eV) indicates that the boron may exist inside Si nanocrystals. A higher probability of effective boron doping was suggested for Si-rich oxide films with a low oxygen content, Then, structural and optical properties were characterized with a focus on the effects of the boron content on Si quantum dots. The results show that as the boron content increases, the nanocrystal size is slightly reduced and the Si crystallization is suppressed. The photoluminescence intensity of the films is decreased as the boron content increases. This is due to boron-induced defects and/or Auger processes induced by effective doping. These results can provide optimal conditions for future Si quantum dot based solar cells.

After radiotherapy, do bone metastases from gastrointestinal cancers show response rates similar to those of bone metastases from other primary cancers?

PURPOSE

Reports investigating whether the response rates to palliative radiation therapy (RT) for painful bone metastases from gastrointestinal (GI) cancers are similar to rates for bone metastases from other primary cancer sites have been limited. The present study evaluated response rates for symptomatic bone metastases from gi cancers after palliative outpatient rt in the Rapid Response Radiotherapy Program (RRRP).

PATIENTS AND METHODS

We identified 69 patients with bone metastases from gi primaries who received palliative rt in the RRRP clinic during 1999-2006. We extracted records for 31 of these patients during 1999-2003 from an RRRP database that used the Edmonton Symptom Assessment Scale (ESAS). Record for the remaining 38 patients during 2003-2006 were extracted from an RRRP database that used the Brief Pain Inventory (BPI). Eligibility criteria for encryption in the two RRRP databases and for collection of patient demographic information (age, sex, primary cancer site, and Karnofsky performance status) were identical. Response rates for this cohort of metastatic gi patients were then compared to rates for 479 patients receiving palliative RT for bone metastases from other primary cancer sites. Pain scores from the ESAS and BPI and data on analgesic consumption were collected at baseline and by telephone follow-up at 4, 8, and 12 weeks after RT for all patients. Complete (CR), partial (PR), and overall (CR+PR) responses were evaluated according to International Consensus Endpoints.

RESULTS

Assessment of the 69 patients with metastatic GI cancers revealed CR, PR, and CR+PR rates of 18%, 42%, and 61% at 4 weeks; 22%, 35%, and 57% at 8 weeks; and 50%, 21%, and 71% at 12 weeks for evaluable patients. The 479 evaluable patients with metastatic cancer from other primary cancer sites had CR, PR, and CR+PR rates of 25%, 27%, and 51% at 4 weeks; 26%, 22%, and 48% at 8 weeks; and 22%, 29%, and 51% at 12 weeks. No statistically significant differences were observed in RT response rates for bone metastases from GI cancers than from other primary cancer sites.

CONCLUSIONS

After palliative RT, bone metastases from gi cancers demonstrate response rates that are similar to rates for metastases from other primary cancer sites. Patients with symptomatic bone metastases from GI malignancies should be referred for palliative RT as readily as patients with osseous metastases from other primary cancer sites.

Reduction of seizure thresholds following electrical stimulation of sensorimotor cortex is dependent on stimulation intensity and is not related to synaptic potentiation

Epilepsy is characterized as a chronic brain state with a very low seizure threshold, and the occurrence of repeated seizure activity. Currently, there is no animal model of induced epilepsy that allows for the exploration of the brain mechanisms underlying a low seizure threshold without the elicitation of seizures. In this study, we employed repeated application of different intensities of electrical stimulation in an attempt to reduce afterdischarge (seizure) thresholds without eliciting seizures. We utilized an in vivo model of neocortical activation via stimulation of the corpus callosum of the adult rat. The intensities were chosen to be subthreshold (20, 30, 40, 50 microA), near threshold (150 microA), and suprathreshold (250, 500 microA) relative to the mean initial afterdischarge threshold (ADT). We also examined changes in the evoked field responses of the transcallosal pathway to the sensorimotor cortex as a measure of synaptic efficacy. Our results indicated that stimulation at 50 microA was effective at reducing the ADT, while minimizing the number of seizures elicited. Stimulation at 150 microA resulted in the concomitant reduction of ADT and repeated seizures typical of most electrical kindling studies. Finally, the 500 microA group showed repeated seizures, but no reduction of afterdischarge threshold. These stimulation intensities (50 microA, 150 microA, 500 microA and 0 microA-control) can be used to independently determine the brain mechanisms responsible for 1) the acquisition of a low afterdischarge threshold independent of the reorganizing effect of repeated seizures, and 2) the elicitation of repeated seizures independent of stimulation induced reduction of afterdischarge threshold.

Worst, Average or Current Pain in the Brief Pain Inventory: Which Should be Used to Calculate the Response to Palliative Radiotherapy in Patients with Bone Metastases?

AIMS

To determine which pain intensity scale in the Brief Pain Inventory correlates best with functional interference and should be used to calculate the response to palliative radiotherapy. To determine the differences in functional interference scores for patients classified as responders and non-responders to palliative radiotherapy.

PATIENTS AND METHODS

All patients referred to the Rapid Response Radiotherapy Program for palliative radiotherapy of symptomatic bone metastases were considered for the study. Patients rated the intensity and functional interference of their pain at the irradiated sites according to the Brief Pain Inventory before and 2 months after radiotherapy. Worst, average and current pain scores were correlated with functional interference scores using Spearman rank coefficients. Responders and non-responders to palliative radiotherapy were defined for each pain intensity scale according to the end points specified by the International Bone Metastases Consensus Working Party. Average differences between responders and non-responders were compared using a Wilcoxon rank sum test.

RESULTS

Between May 2003 and June 2005, 199 patients enrolled in the study (102 men and 97 women). Ninety-five patients returned complete questionnaires at 2 months of follow-up. All pain intensity and interference scores for evaluable patients were significantly lower at 2 months (P<0.0021). Response rates differed depending on the definition of pain intensity. An overall response rate was observed in 66, 58 and 54% of patients for worst, average and current pain, respectively. Worst pain showed the best correlation with functional interference. Responders reported significantly larger decreases in functional interference scores at follow-up in general activity, normal work, enjoyment of life and average functional interference.

CONCLUSION

Worst pain intensity had higher correlations with all functional interference scores except relationships with others. Therefore, we recommend an 11-point scale measuring worst pain to evaluate response rates in future radiotherapy trials. The mean difference from baseline to follow-up in functional interference scores was significantly larger in patients who responded to radiotherapy treatment.