Treatment of COVID-19 Patients with Two Units of Convalescent Plasma in a Resource-Constrained State

IMPORTANCE

Many therapies are used to treat COVID-19, the disease caused by the virus SARS-CoV-2, including convalescent plasma. The clinical utility of using 2 units of convalescent plasma for COVID-19 hospitalized patients is not fully understood.

OBJECTIVE

Many therapies are used to treat COVID-19, the disease caused by the virus SARS-CoV-2, including convalescent plasma. The clinical utility of using 2 units of convalescent plasma for COVID-19 hospitalized patients is not fully understood. Our study aims to determine the safety and efficacy of treating hospitalized COVID-19 patients with 2 units of COVID-19 convalescent plasma (CCP).

METHOD

This was a retrospective study of Arkansas patients treated with CCP using the (US) Food and Drug Administration (FDA) emergency Investigational New Drug (eIND) mechanism from April 9, 2020, through August 9, 2020. It was a multicenter, statewide study in a low-resource setting, which are areas that lack funding for health care cost coverage on various levels including individual, family, or social. Adult patients (n = 165, volunteer sample) in Arkansas who were hospitalized with severe or life-threatening acute COVID-19 disease as defined by the FDA criteria were transfused with 2 units of CCP (250 mL/unit) using the FDA eIND mechanism. The primary outcome was 7- and 30-day mortality after the second unit of CCP.

RESULTS

Unadjusted mortality was 12.1% at 7 days and 23.0% at 30 days. The unadjusted mortality was reduced to 7.7% if the first CCP unit was transfused on the date of diagnosis, 8.7% if transfused within 3 days of diagnosis, and 32.0% if transfused at or after 4 or more days of diagnosis. The risk of death was higher in patients that received low, negative, or missing titer CCP units in comparison to those that received higher titer units.

CONCLUSION

The provision of 2 units of CCP was associated with a reduction in mortality in patients treated with high titer units within 3 days of COVID-19 diagnosis. Given the results, CCP is a viable, low-cost therapy in resource-constrained states and countries.

Estimated glucose disposal rate as a candidate biomarker for thrombotic biomarkers in T1D: a pooled analysis

PURPOSE

To determine the utility of estimated glucose disposal rate (eGDR) as a candidate biomarker for thrombotic biomarkers in patients with type 1 diabetes (T1D).

METHODS

We reanalysed baseline pretreatment data in a subset of patients with T1D from two previous RCTs, consisting of a panel of thrombotic markers, including fibrinogen, tissue factor (TF) activity, and plasminogen-activator inhibitor (PAI)-1, and TNFα, and clinical factors (age, T1D duration, HbA1c, insulin requirements, BMI, blood pressure, and eGDR). We employed univariate linear regression models to investigate associations between clinical parameters and eGDR with thrombotic biomarkers.

RESULTS

Thirty-two patients were included [mean ± SD age 31 ± 7 years, HbA1c of 58 ± 9 mmol/mol (7.5 ± 0.8%), eGDR 7.73 ± 2.61]. eGDR negatively associated with fibrinogen (P < 0.001), PAI-1 concentrations (P = 0.005), and TF activity (P = 0.020), but not TNFα levels (P = 0.881). We identified 2 clusters of patients displaying significantly different characteristics; 56% (n = 18) were categorised as 'higher-risk', eliciting significantly higher fibrinogen (+ 1514 ± 594 μg/mL; P < 0.001), TF activity (+ 59.23 ± 9.42 pmol/mL; P < 0.001), and PAI-1 (+ 8.48 ± 1.58 pmol/dL; P < 0.001), HbA1c concentrations (+ 14.20 ± 1.04 mmol/mol; P < 0.001), age (+ 7 ± 3 years; P < 0.001), duration of diabetes (15 ± 2 years; P < 0.001), BMI (+ 7.66 ± 2.61 kg/m²; P < 0.001), and lower mean eGDR (- 3.98 ± 1.07; P < 0.001).

CONCLUSIONS

Compared to BMI and insulin requirements, classical surrogates of insulin resistance, eGDR is a suitable and superior thrombotic risk indicator in T1D.

TRIAL REGISTRATION

ISRCTN4081115; registered 27 June 2017.

A kinetic and thermodynamic investigation into the removal of methyl orange from wastewater utilizing fly ash in different process configurations

The removal of methyl orange using coal fly ash, which is a widely available low-cost adsorbent, has been investigated. Adsorption studies for dye removal were conducted using various configurations such as batch, column and heap adsorption at various temperatures and adsorbent dosages at neutral pH. The Langmuir, Freundlich and Tempkin isotherm models were used to describe the process. The Freundlich model best represented the adsorption. Kinetic studies show the adsorption followed pseudo-second-order kinetics. Thermodynamic studies show that the process is spontaneous, endothermic and random. Column configuration was found to be the most efficient with a dye removal percentage of 99.95%, followed by heap adsorption at 99.25% removal and lastly batch configuration with 96.68% removal. Economic analysis shows that column operation would be the most effective for practical implementation.

Provision of COVID-19 Convalescent Plasma in a Resource-Constrained State

BACKGROUND

Arkansas is a rural state of 3 million people. It is ranked fifth for poverty nationally. The first case of coronavirus disease 2019 (COVID-19) in Arkansas occurred on 11 March 2020. Since then, approximately 8% of all Arkansans have tested positive. Given the resource limitations of Arkansas, COVID-19 convalescent plasma (CCP) was explored as a potentially lifesaving, therapeutic option. Therefore, the Arkansas Initiative for Convalescent Plasma was developed to ensure that every Arkansan has access to this therapy.

STUDY DESIGN AND METHOD

This brief report describes the statewide collaborative response from hospitals, blood collectors, and the Arkansas Department of Health (ADH) to ensure that CCP was available in a resource-limited state.

RESULTS

Early contact tracing by ADH identified individuals who had come into contact with "patient zero" in early March. Within the first week, 32 patients tested positive for COVID-19. The first set of CCP collections occurred on 9 April 2020. Donors had to be triaged carefully in the initial period, as many had recently resolved their symptoms. From our first collections, with appropriate resource and inventory management, we collected sufficient CCP to provide the requested number of units for every patient treated with CCP in Arkansas.

CONCLUSIONS

The Arkansas Initiative, a statewide effort to ensure CCP for every patient in a resource-limited state, required careful coordination among key players. Collaboration and resource management was crucial to meet the demand of CCP products and potentially save lives.

1207 Keep It Simple: Wireless Patches For Home Sleep Diagnostics

Introduction

Despite growing use of home sleep testing for the diagnosis of obstructive sleep apnea (OSA), there are significant barriers including limited availability, high cost, and complex wires making it difficult for patients to use on their own. The objective of this study was to evaluate a new flexible, thin, and wireless adhesive patch (proprietor sensors, TatchSleep Pro [TSP]) for the detection of OSA and compare the validity to overnight polysomnography (PSG). The TSP transmits data wirelessly to a smartphone app which in turn uploads the data to a cloud server. Data is presented to a sleep professional via a dedicated interface to score and analyze the results.

Methods

Patients (n=9; mean age=47 (SD=10); mean BMI=33 (SD=6.6); 4 males) undergoing a PSG evaluation for OSA also wore 2 TSP patches applied on the chest and abdomen. The TSP patches detected respiratory effort, derived airflow, derived pressure, body position and movement. Two sets of respiratory data (with common SpO2 and heartrate as a reference from PSG) were created, one from PSG and one from the TSP. The data were then scored by a certified sleep technician, blinded to the conditions. Linear regression analyses were used to compare the two derived apnea-hypopnea indices (AHI). In the morning, all participants were asked about their experience using the TSP. The study was approved by the Western IRB.

Results

There was a significant correlation for AHI between the TSP and PSG (R2= 0.94; p&lt;0.01). All participants found the TSP comfortable to wear and indicated that removing the patches was ‘easy’ or ‘very easy,’

Conclusion

These preliminary results suggest the wireless TSP may be an effective, cost-efficient way to evaluate OSA. Despite small sample, results show promise as a new innovative product for home sleep testing.

Support

Supported by Tatch Inc.

Identification of Optimum Panel of Blood-based Biomarkers for Alzheimer's Disease Diagnosis Using Machine Learning

With the increasing number of people living with Alzheimer's disease (AD), there is a need for low-cost and easy to use methods to detect AD early to facilitate access to appropriate care pathways. Neuroimaging biomarkers (such as those based on PET and MRI) and biochemical biomarkers (such as those based on CSF) are recommended by international guidelines to facilitate diagnosis. However, neuroimaging is expensive and may not be widely available and CSF testing is invasive. Bloodbased biomarkers offer the potential for the development of a low-cost and more time efficient tool to detect AD to complement CSF and neuroimaging as blood is much easier to obtain. Although no single blood biomarker is yet able to detect AD, combinations of biomarkers (also called panels) have shown good results. However, a large number of biomarkers are often needed to achieve a satisfactory detection performance. In addition, it is difficult to reproduce reported results within and across different study cohorts because of data overfitting and lack of access to the datasets used in the studies. In this study, our focus is to identify an optimum panel (in terms of the least number of blood biomarkers to meet the specified diagnostic performance of 80% sensitivity and specificity) based on a widely accessible data set, and to demonstrate a testing methodology that reinforces reproducibility of results. Realizing a panel with reduced number of markers will have significant impact on the complexity and cost of diagnosis and potential development of cost-effective point of care devices.

Proteomic analysis of JAK2V617F-induced changes identifies potential new combinatorial therapeutic approaches

In excess of 90% of patients with polycythaemia vera (PV) express a mutated form of Janus kinase 2 (JAK2), JAK2V617F. Such aberrant proteins offer great potential for the treatment of these diseases; however, inhibitors to JAK2 have had limited success in the clinic in terms of curing the disease. To understand the effects of this oncogene in haematopoietic cells with the aim of improving treatment strategies, we undertook a systematic evaluation of the effects of JAK2V617F expression using proteomics. The effects of JAK2V617F on over 5000 proteins and 2000 nuclear phosphopeptide sites were relatively quantified using either SILAC or eight-channel iTRAQ mass spectrometry. Pathway analysis of the proteins identified as changing indicated disruption to the p53 and MYC signalling pathways. These changes were confirmed using orthogonal approaches. The insight gained from this proteomic analysis led to the formation of hypothesis-driven analysis on inhibitor-mediated effects on primary cells from patients with a JAK2V617F mutation. Simultaneous inhibition of MYC and upregulation of p53 led to the preferential extinction of JAK2V617F-positive CD34+ cells, illustrating a potential therapeutic benefit from combined targeting of p53 and MYC.

Identification of blood biomarkers for use in point of care diagnosis tool for Alzheimer's disease

Early diagnosis of Alzheimer's Disease (AD) is widely regarded as necessary to allow treatment to be started before irreversible damage to the brain occur and for patients to benefit from new therapies as they become available. Low-cost point-of-care (PoC) diagnostic tools that can be used to routinely diagnose AD in its early stage would facilitate this, but such tools require reliable and accurate biomarkers. However, traditional biomarkers for AD use invasive cerebrospinal fluid (CSF) analysis and/or expensive neuroimaging techniques together with neuropsychological assessments. Blood-based PoC diagnostics tools may provide a more cost and time efficient way to assess AD to complement CSF and neuroimaging techniques. However, evidence to date suggests that only a panel of biomarkers would provide the diagnostic accuracy needed in clinical practice and that the number of biomarkers in such panels can be large. In addition, the biomarkers in a panel vary from study to study. These issues make it difficult to realise a PoC device for diagnosis of AD. An objective of this paper is to find an optimum number of blood biomarkers (in terms of number of biomarkers and sensitivity/specificity) that can be used in a handheld PoC device for AD diagnosis. We used the Alzheimer's disease Neuroimaging Initiative (ADNI) database to identify a small number of blood biomarkers for AD. We identified a 6-biomarker panel (which includes A1Micro, A2Macro, AAT, ApoE, complement C3 and PPP), which when used with age as covariate, was able to discriminate between AD patients and normal subjects with a sensitivity of 85.4% and specificity of 78.6%.

Endemic goitre and hypothyroidism in an adult female patient dependent on total parenteral nutrition

We present the case of a thirty-year-old female patient who was referred to the endocrinology team with an enlarging goitre and biochemical hypothyroidism. She had been dependent on total parenteral nutrition for the previous six years as a result of intestinal failure thought to be caused by possible underlying mitochondrial disease. The patient also suffers from a Desmin myopathy, and at present, the exact aetiology behind her intestinal failure is not certain. The goitre was smooth and had been enlarging slowly over the previous few months. Thyroid peroxidase antibodies were found to be within normal range. Further analysis of the case showed that twelve months earlier the patients total parenteral nutrition (TPN) feed had been altered as a result of manganese toxicity. The current feeding regimen did not contain a trace element additive which had previously supplied iodine supplementation. A little detective work established that iodine content to the TPN had been reduced, the trace element additive (Additrace) was recommenced providing 1 µmol of iodine per day, equating to 130 µg of iodine. Following this change, thyroid-stimulating hormone levels returned to normal and the goitre quickly reduced in size. We present a rare case of endemic goitre and hypothyroidism in a patient receiving inadequate iodine supplementation through total parenteral nutrition.

A device for characterising the mechanical properties of the plantar soft tissue of the foot

The plantar soft tissue is a highly functional viscoelastic structure involved in transferring load to the human body during walking. A Soft Tissue Response Imaging Device was developed to apply a vertical compression to the plantar soft tissue whilst measuring the mechanical response via a combined load cell and ultrasound imaging arrangement. Accuracy of motion compared to input profiles; validation of the response measured for standard materials in compression; variability of force and displacement measures for consecutive compressive cycles; and implementation in vivo with five healthy participants. Static displacement displayed average error of 0.04 mm (range of 15 mm), and static load displayed average error of 0.15 N (range of 250 N). Validation tests showed acceptable agreement compared to a Houndsfield tensometer for both displacement (CMC > 0.99 RMSE > 0.18 mm) and load (CMC > 0.95 RMSE < 4.86 N). Device motion was highly repeatable for bench-top tests (ICC = 0.99) and participant trials (CMC = 1.00). Soft tissue response was found repeatable for intra (CMC > 0.98) and inter trials (CMC > 0.70). The device has been shown to be capable of implementing complex loading patterns similar to gait, and of capturing the compressive response of the plantar soft tissue for a range of loading conditions in vivo.

Compliance and persistence to oral bisphosphonate therapy following initiation within a secondary fracture prevention program: a randomised controlled trial of specialist vs. non-specialist management

Following initiation of oral bisphosphonate therapy through a secondary fracture prevention program, 2-year treatment compliance and persistence remained high and were similar in patients randomised to follow-up by either the program or primary care physician. Thus, community-based and specialist management are equally effective in supporting compliance and persistence with anti-osteoporotic treatments.

INTRODUCTION

The purpose of this study was to determine whether management by a secondary fracture prevention (SFP) program (aka "fracture liaison service") results in better compliance and persistence to oral bisphosphonate therapy than follow-up by the primary care physician, after initiation within an SFP program.

METHODS

This prospective RCT included 102 patients with incident osteoporotic fractures referred to a SFP program in Sydney, Australia. Following oral bisphosphonate therapy initiation, patients were randomised to either 6-monthly follow-up with the SFP program (group A) or referral to their primary care physician with a single SFP program visit at 24 months (group B). Compliance and persistence to treatment were measured using pharmaceutical claims data. Predictors of compliance and persistence and associations between compliance and persistence, and changes in bone mineral density (BMD) or bone resorption marker, urinary deoxypyridinoline over 24 months were analysed.

RESULTS

The median medication possession ratio at 24 months was 0.78 (IQR, 0.50-0.93) in group A and 0.79 (IQR, 0.48-0.96) in group B (p = 0.68). Persistence at 24 months was also similar in both groups (64 vs. 61%, respectively; p = 0.75). After adjusting for confounders, patients in group A were not more likely to be compliant (OR, 1.06; 95% CI, 0.46-2.47) or persistent (HR, 0.83; 95% CI, 0.27-1.67) than those randomised to group B. Time-based changes in BMD or bone turnover were not associated with compliance or persistence.

CONCLUSION

Compliance and persistence to oral bisphosphonate therapy remain high amongst patients initiated within an SFP program, with community-based and SFP program management being equally effective in maintaining therapeutic compliance and persistence over 2 years. These results indicate that one of the main functions of an SFP program may be the initiation of therapy rather than continuous patient monitoring.

Abstract P5-14-15: Discovery and validation of simple heart measurements to screen patients who will benefit from deep inspiration breath hold for left breast irradiation

Purpose:

Deep inspiration breath hold (DIBH) using active breath control in left-sided breast irradiation (RT) can significantly reduce radiation dose to heart and coronary arteries in selected patients. At our institution, a cutoff of V50% &gt;10cc is currently used to identify patients who require DIBH. This dose-volume cutoff requires generation of a radiation plan in order to select patients. The purpose of this study was to identify simple 2-D measurements of the heart at the time of CT simulation that can help screen patients for DIBH in order to streamline the process for left-sided breast RT.

Methods:

This study evaluated CT simulation scans from 50 left-sided breast cancer patients treated with tangent RT alone, where 50% of patients were treated with DIBH. On each CT dataset, a tangential line was drawn between the medial and lateral tattoos. The following heart measurements were recorded by a blinded observer at 2, 3, 4, and 5 cm below the tattoos: (1) maximal heart distance (MHD) perpendicular to this line and (2) heart length (HL) along this line. Predictive models were created using two strategies; (1) step wise approach utilizing the most significant factor and (2) principle component analysis. Using C-statistics, 3 cutoffs with the highest correlations with heart dose were determined from the model. These cutoffs were validated in a cohort of 100 consecutive patients treated from Jan-May 2012.

Results:

Data from 49 patients in the derivation cohort were analyzable. The HL at 2 cm had the strongest correlation with V50 (R2 = 0.45; p &lt;0.0001). Other values that were associated with V50 were HL at 3 cm (R2 = 0.37; p = &lt;0.0001), MHD at 2cm (R2 = 0.25; p = 0.0003), MHD at 3 cm (R2 = 0.23; p = 0.0006) and HL at 4 cm (R2 = 0.17, p = 0.0035). The predictive model using HL at 2 cm gave an adjusted R2 = 0.4385 (P&lt;0.0001). Adding other variables into the predictive model did not improve the adjusted R2. The following 3 cutoffs for HL at 2 cm with respective (sensitivity; specificity) were identified: 3.92 cm (0.955; 0.48), 7.65 cm (0.32; 0.48), and 6.5 cm (0.5; 0.8). In the validation cohort, 22/100 had V50% &gt; 10 cc. Validation of the 3 derived cutoffs for HL at 2 cm yielded the following sensitivities and specificities: 1.0 and 0.28 for 3.92 cm; 0.53 and 0.93 for 7.65 cm; 0.58 and 0.69 for 6.5 cm. Positive predictive value (PPV) and negative predictive value (NPV) were as follows: 3.92 cm (PPV = 0.25; NPV = 1.00). 7.65 cm (PPV = 0.63; NPV = 0.89), and 6.5cm (PPV = 0.30; NPV = 0.87).

Conclusions:

A simple 2-D heart measurement, heart length at 2 cm below the tattoos, had moderate correlation with the irradiated heart volume. Although HL at 2 cm did not have both high specificity and sensitivity to predict who would benefit from DIBH, cut-offs could be selected to maximize sensitivity (3.92 cm for sensitivity 1.0) or specificity (7.65 cm for specificity 0.93). For example, in departments that routinely acquire both free-breathing and DIBH CT simulation scans for all left-sided patients, a cutoff of 3.92cm would minimize the number of unnecessary DIBH scans.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-14-15.

Pitpnm1 is expressed in hair cells during development but is not required for hearing

•

We studied the expression of Pitpnm1 in the developing mouse inner ear.

•

We covered several ages between E14.5 and P5, and also looked at adults.

•

Pitpnm1 is expressed in the inner hair cells from before birth to adulthood.

•

Pitpnm1 is expressed transiently in the outer hair cells at early postnatal stages.

•

Mice lacking Pitpnm1 display no obvious auditory defects.

Deafness is a genetically complex disorder with many contributing genes still unknown. Here we describe the expression of Pitpnm1 in the inner ear. It is expressed in the inner hair cells of the organ of Corti from late embryonic stages until adulthood, and transiently in the outer hair cells during early postnatal stages. Despite this specific expression, Pitpnm1 null mice showed no hearing defects, possibly due to redundancy with the paralogous genes Pitpnm2 and Pitpnm3.

The role of comorbidities on the uptake of systemic treatment and 3-year survival in older cancer patients

BACKGROUND

Older patients are notably absent from clinical trials. Thus, observational studies are the primary avenue for understanding the role of comorbidity in cancer care and survival. We examined the impact of comorbidity on systemic treatment initiation and 3-year survival in a cohort of older cancer patients.

PATIENTS AND METHODS

Our cohort comprised 2753 Australian veterans aged ≥65 years with full health coverage and a cancer registry notification for colorectal (CRC), breast, prostate or non-small-cell lung cancer (NSCLC). We established comorbidities based on drugs prescribed in the 6 months prior to cancer diagnosis.

RESULTS

Patients with higher comorbidity burden were more likely to receive systemic treatment for prostate cancer [adjusted odds ratio 1.21, 95% confidence interval (CI) 1.05-1.39] but less likely for NSCLC (0.63, 95% CI 0.45-0.86). After adjusting for receipt of treatment, increased comorbidity resulted in shorter survival for CRC [adjusted hazard ratio (aHR) 1.16, 95% CI 1.07-1.26] and breast cancer (aHR 1.23, 95% CI 1.02-1.48). However, we did not demonstrate significant improvements in 3-year survival for patients receiving systemic treatment.

CONCLUSION

Comorbidity influences systemic treatment uptake and adversely affects survival, with impact dependent upon comorbidity and cancer type. Clinical trials should be undertaken in older patients to better understand the risks and benefits of cancer treatments.

Medical students' perceptions of using e-learning to enhance the acquisition of consulting skills

BACKGROUND

This study aims to evaluate medical students' perception of the usefulness and effectiveness of an e-learning package developed to enhance the acquisition of consulting skills.

METHOD

A survey with mixed method data analysis was conducted. Participants were 67 medical students completing their third year primary care rotation as part of a five-year degree at the University of Tasmania. Participants completed a 10 question anonymous online survey after using the elearning package

RESULTS

Of the participants, 92% found it enjoyable and 95% found the e-learning package useful; 75% perceived it to be effective in increasing their performance and 91% believed it increased their knowledge in consulting skills. Benefits for participants' confidence, style and structure of consulting skills were found.

CONCLUSION

Participants found the e-learning package to be enjoyable and effective. E-learning should be further utilised in a blended learning environment to support face-to-face teaching in consulting skills.

The efficacy of HER2-targeted agents in metastatic breast cancer: a meta-analysis

BACKGROUND

The addition of HER2-targeted agents to standard treatment has been shown to improve outcomes for HER2 positive metastatic breast cancer patients. We undertook a meta-analysis to evaluate the efficacy of HER2-targeted therapy in addition to standard treatment in metastatic breast cancer patients.

PATIENTS AND METHODS

Eligible trials were randomised controlled trials (RCTs) comparing the addition of HER2 therapy to standard treatment (hormone or chemotherapy) reporting overall survival (OS), time to progression (TTP), progression-free survival (PFS) and/or response rates.

RESULTS

Eight trials comprising 1848 patients were eligible for inclusion. HER2-targeted agents were trastuzumab and lapatinib and therapeutic partners were taxanes (4 RCTs), anthracyclines (1), capecitabine (2), anastrozole (1) and letrozole (1). The addition of HER2-targeted agents improved OS [hazard ratios (HR) 0.78; 95% confidence interval (CI) 0.67-0.91], TTP (HR 0.56; 95% CI 0.48-0.64), PFS (HR 0.63; 95% CI 0.53-0.74) and overall response rate (relative risk 1.67; 95% CI 1.46-1.90).

CONCLUSIONS

Our meta-analysis confirms the benefit of adding HER2-targeted therapy to standard treatment in HER2 positive metastatic breast cancer. Compared with OS, TTP, PFS and ORR overestimate treatment benefit. Trials in our meta-analysis differed in terms of partner drug or HER2 agents, yet delivered comparable outcomes.

Analysis of collagen fibre shape changes in breast cancer

Second harmonic generation microscopy was performed on both normal and diseased breast tissue. Differences in the collagen fibre shape between normal, benign and malignant breast tissue were compared and quantified using elliptical Fourier analysis. Principal shape analysis of these coefficients provided an understanding of the key differences in collagen fibre shape between the three tissue types. A Gaussian model was also used to associate the shape of the fibre with the probability that it had been sampled from malignant breast tissue. These results provide quantitative evidence for the alteration of collagen fibre shape in both benign and malignant breast tissue.

Synchrotron-based in vivo tracking of implanted mammalian cells

We have developed an X-ray imaging protocol that permits 3D visualisation of a small number of implanted cells within bulk tissue. The cells are marked using natural endocytosis of inert gold nano-particles. The resulting local increase in electron density allows high imaging contrast to be obtained from small clusters of these marked cells. Using this technique we have imaged C6 glioma cells within the brain of a model animal. The cells were marked by exposing them to colloidal gold incorporated in the growth media. Gold-loaded glioma cells were implanted into the brains of adult male Wistar rats. After tumours had been allowed to develop for up to 2 weeks, the animals were sacrificed and images of the intact cranium were acquired at the SYRMEP imaging station on the Elettra synchrotron in Italy. Computed tomography was performed using mixed absorption and phase contrast techniques at an X-ray energy of 24 keV. In the resulting volume datasets the tumour bulk is clearly visible and the infiltrating nature of the malignant growth is well demonstrated. Although the protocol was developed using this particular model of malignant brain tumour, it is believed that it will be possible to use it with other cell lines.

Dissecting obesogenic behaviours: the development and application of a test battery for targeting prescription for weight loss

There are limited practical tools to help clinicians or public health workers manage obesity in their patients. We have previously developed a scanning technique for diagnosing environments leading to obesity (Analysis Grid for Environments/Elements Leading to Obesity). Here we describe the development of a tool for identifying behaviours in an individual most likely to lead to obesity. A questionnaire battery of five tests called the DAB-Q (Diet, Activity and Behaviour Questionnaire) was developed, piloted and internally validated with overweight women from a commercial weight loss programme. Outcome from the tests, which are available free on the Internet, provides clinicians with a simple, effective and time-saving tool for ranking foods, drinks and activities likely to be most effectively targeted for weight loss in an individual. This is based on total scores derived from measures of frequency, potential for change and potency of each item as a potential contributor to overweight.

Power demodulation of local field potential recordings

Local field potentials (LFPs) are used to monitor the activity of large groups of neurons with macroelectrodes. Historically traditional linear statistical analysis techniques based on second order moments have been used to analyze these signals. We describe a new method based on power demodulation for estimating the instantaneous firing rate that is common to the neural activity of the most prominent neurons sensed by the electrodes. Correlated firing rates among neighboring neurons are common in many neurological structures and pathologies such as tremor. We validate our estimator with a Monte Carlo simulation based on a novel statistical model of LFPs. Our results show that the power demodulation approach can achieve a correlation of >0.80 with the common firing rate. This suggests that it may be possible to estimate the common intensity of a group neurons in recordings which are too noisy or contain too many neurons to apply spike detection or spike sorting algorithms.

Application of mobile phone technology for managing chemotherapy-associated side-effects

BACKGROUND

Novel mobile phone technology linked to a server that communicates patients' symptoms to healthcare professionals has been adapted to register the side- effects of chemotherapy and provide advice on management of toxicity. We report a feasibility study to examine the utility of home monitoring of patients' symptoms via a mobile phone.

METHODS

Six colon cancer patients receiving adjuvant chemotherapy, entered symptom data onto user friendly screens on a mobile phone twice daily. This 'real time' self assessment of nausea, vomiting, mucositis, diarrhoea and hand-foot syndrome and measurement of temperature was sent via a secured connection to a remote computer. In the event of moderate or severe symptoms (generating amber and red alerts respectively), the nurse was immediately alerted by the computer, via a pager. The nurse then contacted the patient to reinforce the automatic advice sent to the patient on their phone and to assess the patient using clinical algorithms.

RESULTS

The patient used the mobile phones during the first two cycles of chemotherapy. The data were successfully analysed by the server software and alerts were generated alerting the study nurses to patients' symptoms at the appropriate time. There were 91 alerts-54 red and 37 amber; 54% (29/54) of the red alerts were data delay and transmission problems which were swiftly rectified. The remaining red alerts were managed appropriately by the study nurses. Both patients and staff felt confident in this approach to symptom management.

CONCLUSIONS

This study demonstrates that the technology for monitoring patients' symptoms worked well. The patients felt secure in the knowledge that their symptoms were being closely monitored and that they were participating effectively in their own care management.

Preoperative Nutritional Status Predicts the Severity of the Systemic Inflammatory Response Syndrome (SIRS) Following Major Vascular Surgery

OBJECTIVES

This study examined the relationship between pre-operative nutritional status and systemic inflammatory response syndrome (SIRS) or sepsis following major vascular surgery.

DESIGN AND METHODS

Subjects undergoing open AAA repair, EVAR or lower limb revascularisation were studied prospectively. Pre-operative nutrition was assessed clinically using Mini-Nutritional Assessment (MNA) and body composition was measured by dual energy X-ray absorptiometry (DEXA) scanning. SIRS severity was assessed for 5 post-operative days and sepsis noted within 30 days of surgery.

RESULTS

Using MNA, neither SIRS severity nor sepsis occurrence differed significantly between 'well-nourished' subjects and those 'at risk of malnutrition'. Using DEXA, negative associations existed between body mass index and both SIRS score and SIRS duration. Fat free mass (FFM) was negatively associated with SIRS score and duration. Negative associations also existed between skeletal muscle mass (SMM) and SIRS score and duration. SMM was also negatively correlated with post-operative length of stay in hospital. There were no significant correlations between sepsis and any nutritional indices.

CONCLUSIONS

Lower pre-operative nutritional indices, indicating protein energy malnutrition, were associated with more severe systemic inflammatory responses following major vascular surgery.

Physiologic responses to acupuncture point stimulation: a pilot study to evaluate methods and instrumentation

The physiological responses to needle stimulation of an acupuncture point and a nearby control point were compared in six healthy participants. The electrocardiogram (ECG), respiration, and electrodermal response (EDR) were measured along with the times of needle insertion, interim needle stimulation and needle removal. In addition to the aforementioned, any relevant events such as movement of the subject, unexpected noise, etc were annotated.

Variable frequency bioimpedance instrumentation

The design of instrumentation used to measure the bioimpedance of skin or tissue is presented. An inexpensive, component level approach, appropriate for use by researchers rather that commercial applications, is emphasized. The design and implementation process is thoroughly explained and design tradeoffs are discussed with relation to various applications. A validation of the implementation in hardware is presented and an example application to skin impedance topography is considered.

Stereotactic body radiotherapy (SBRT) and medical inoperability of early stage non-small cell lung cancer

17074

Background: Early stage NSCLC is commonly diagnosed in elderly patients who often have significant medical co-morbidity. SBRT is emerging as a treatment alternative that can provide 80–97% local control for peripheral tumors. We performed a literature review and a retrospective review of 24 patients referred to Princess Margaret Hospital for consideration of SBRT to assess what criteria were used to determine patient selection for this new treatment. Methods: Published papers reporting treating stage I NSCLC with SBRT were reviewed. Clinical and demographic characteristics of patients referred for consideration of SBRT over the last 15 months were analyzed. All patients were assessed by experienced thoracic surgeons to determine their operability status. Patients were retrospectively scored as average or high risk for surgery on the basis of accepted PFT guidelines (FEV1 and DLCO <40% predicted); Charlson Index of Comorbidity (CCI) was calculated (score >2 associated with impaired survival). Results: Of 13 papers reporting Stage 1 SBRT results, 8 included details of medical inoperability. 2 papers had strict guidelines for PFTs, in addition to other criteria. In 6 studies reporting 276 pts, the most common reason for inoperability was non-specific medical comorbidity (60%). Our cohort (24 patients) referred for SBRT (median age 75, range 57–89) had a mean tumour size of 2.32cm (S.D. 1.11); 50% of patients had a good (0–1) Zubrod Performance status. Based upon PFT tests alone 10 patients (42%) were high risk and 5 (21%) average risk for surgery. The CCI score was ≥3 in 10 patients (42%). 3 patients who scored average risk and CCI ≤2 were deemed medically inoperable due a single severe medical comorbity. In 23/24 pts the surgeon recommended against surgery; one patient refused surgery. Conclusions: With an aging population and increased detection due to incidental finding or screening, it is important to know that there is effective alternative therapy for patients deemed too high risk for surgical resection. Comorbidity is an important factor influencing surgical mortality; defining explicit criteria for inoperability remains a clinical challenge.

No significant financial relationships to disclose.

Wavelet-based feature extraction applied to small-angle x-ray scattering patterns from breast tissue: a tool for differentiating between tissue types

This paper reports on the application of wavelet decomposition to small-angle x-ray scattering (SAXS) patterns from human breast tissue produced by a synchrotron source. The pixel intensities of SAXS patterns of normal, benign and malignant tissue types were transformed into wavelet coefficients. Statistical analysis found significant differences between the wavelet coefficients describing the patterns produced by different tissue types. These differences were then correlated with position in the image and have been linked to the supra-molecular structural changes that occur in breast tissue in the presence of disease. Specifically, results indicate that there are significant differences between healthy and diseased tissues in the wavelet coefficients that describe the peaks produced by the axial d-spacing of collagen. These differences suggest that a useful classification tool could be based upon the spectral information within the axial peaks.