Novel Inhibitors to MmpL3 Transporter of Mycobacterium tuberculosis by Structure-Based High-Throughput Virtual Screening and Molecular Dynamics Simulations

Tuberculosis (TB)-causing bacterium Mycobacterium tuberculosis (Mtb) utilizes mycolic acids for building the mycobacterial cell wall, which is critical in providing defense against external factors and resisting antibiotic action. MmpL3 is a secondary resistance nodulation division transporter that facilitates the coupled transport of mycolic acid precursor into the periplasm using the proton motive force, thus making it an attractive drug target for TB infection. In 2019, X-ray crystal structures of MmpL3 from M. smegmatis were solved with a promising inhibitor SQ109, which showed promise against drug-resistant TB in Phase II clinical trials. Still, there is a pressing need to discover more effective MmpL3 inhibitors to counteract rising antibiotic resistance. In this study, structure-based high-throughput virtual screening combined with molecular dynamics (MD) simulations identified potential novel MmpL3 inhibitors. Approximately 17 million compounds from the ZINC15 database were screened against the SQ109 binding site on the MmpL3 protein using drug property filters and glide XP docking scores. From this, the top nine compounds and the MmpL3-SQ109 crystal complex structure each underwent 2 × 200 ns MD simulations to probe the inhibitor binding energetics to MmpL3. Four of the nine compounds exhibited stable binding properties and favorable drug properties, suggesting these four compounds could be potential novel inhibitors of MmpL3 for M. tuberculosis.

A systematic review of the literature reporting on remote monitoring epileptic seizure detection devices

BACKGROUND

Early detection and alert notification of an impending seizure for people with epilepsy have the potential to reduce Sudden Unexpected Death in Epilepsy (SUDEP). Current remote monitoring seizure detection devices for people with epilepsy are designed to support real-time monitoring of their vital health parameters linked to seizure alert notification. An understanding of the rapidly growing literature on remote seizure detection devices is essential to address the needs of people with epilepsy and their carers.

AIM

This review aims to examine the technical characteristics, device performance, user preference, and effectiveness of remote monitoring seizure detection devices.

METHODOLOGY

A systematic review referenced to PRISMA guidelines was used.

RESULTS

A total of 1095 papers were identified from the initial search with 30 papers included in the review. Sixteen non-invasive remote monitoring seizure detection devices are currently available. Such seizure detection devices were found to have inbuilt intelligent sensor functionality to monitor electroencephalography, muscle movement, and accelerometer-based motion movement for detecting seizures remotely. Current challenges of these devices for people with epilepsy include skin irritation due to the type of patch electrode used and false alarm notifications, particularly during physical activity. The tight-fitted accelerometer-type devices are reported as uncomfortable from a wearability perspective for long-term monitoring. Also, continuous recording of physiological signals and triggering alert notifications significantly reduce the battery life of the devices. The literature highlights that 3.2 out of 5 people with epilepsy are not using seizure detection devices because of the cost and appearance of the device.

CONCLUSION

Seizure detection devices can potentially reduce morbidity and mortality for people with epilepsy. Therefore, further collaboration of clinicians, technical experts, and researchers is needed for the future development of these devices. Finally, it is important to always take into consideration the expectations and requirements of people with epilepsy and their carers to facilitate the next generation of remote monitoring seizure detection devices.

Transient Radiographic Pseudoprogression Following Fractionated SBRT for Primary Renal Cell Carcinoma

PURPOSE/OBJECTIVE(S)

SBRT is an emerging treatment for patients with RCC who are not surgical candidates. Pooled analysis of an international consortium suggests promising short term local control. In the event of local failure, other ablative methods may be used to salvage these patients. Trends in radiographic surveillance are not well characterized post SBRT. In this study we observe a common transient increase in the tumor size followed by stability or decline in patients treated with fractionated SBRT on a phase II clinical protocol.

MATERIALS/METHODS

Radiographic studies of patients enrolled in a phase II clinical trial were reviewed for this report. Primary RCC tumors were treated using SBRT with two fractionation schema (48 Gy in 3 or 4 fractions) based on a 5 cm size threshold. Patients were followed with routine imaging per protocol at 3, 6, 12, 18, and 24 months post-treatment. Percent change in greatest dimension is analyzed over time and subsequently stratified by dose, baseline tumor diameter, and PTV. An increase in tumor size by 10% or greater followed by tumor shrinkage or stability was considered a transient increase.

RESULTS

From August of 2013 to December of 2022, 40 patients were enrolled in this trial with a median age of 77.5 and follow up of 18 months. 32 patients with at least two follow up images (minimum of 6 months post-SBRT) were included in the analysis. 26 of these patients were treated with 48 Gy in 3 fractions and 6 were treated with 48 Gy in 3 fractions. Median tumor size was 38.4 cc with a median diameter of 3.5 cm. 46.9% of patients experienced a transient increase with a median increase of 19.7% (range = 63.1, IQR = 13.9%-38.6%) of the pretreatment largest dimension. 66.7% of patients with tumors ≥ 5 cm experienced a transient increase vs. 42.3% of patients with tumors < 5cm. 56.3% of patients with PTV ≥ 38.4 cc experienced a transient increase vs. 40% of patients with a PTV < 38.4cc. Patients with PTV < 38.4 cc experienced a median 19% increase compared with the PTV ≥ 38.4 cc median increase of 37.5%. Most common transient increase was observed at 3 months post treatment. Of patients evaluated with CT scans, 50% experienced a transient increase, compared with 37.5% of those evaluated with MRI scans.

CONCLUSION

SBRT is a promising treatment for primary RCC, however radiographic surveillance of the disease post-treatment is not well characterized. In this study of patients enrolled in a Phase II protocol, there appears to be a transient radiographic increase in the size of primary tumors followed by stability and decline. Further investigations will guide the timing and need for salvage treatment for post- SBRT RCC.

A Literature Review of the Effects of Air Pollution on COVID-19 Health Outcomes Worldwide: Statistical Challenges and Data Visualization

Several peer-reviewed papers and reviews have examined the relationship between exposure to air pollution and COVID-19 spread and severity. However, many of the existing reviews on this topic do not extensively present the statistical challenges associated with this field, do not provide comprehensive guidelines for future researchers, and review only the results of a relatively small number of papers. We reviewed 139 papers, 127 of which reported a statistically significant positive association between air pollution and adverse COVID-19 health outcomes. Here, we summarize the evidence, describe the statistical challenges, and make recommendations for future research. To summarize the 139 papers with data from geographical locations around the world, we also present anopen-source data visualization tool that summarizes these studies and allows the research community to contribute evidence as new research papers are published.

Development and evaluation of a predictive algorithm for unsatisfactory response among patients with pulmonary arterial hypertension using health insurance claims data

OBJECTIVE

This study aimed to develop and validate a predictive algorithm for unsatisfactory response to initial pulmonary arterial hypertension (PAH) therapy using health insurance claims.

METHODS

Adult patients with PAH initiated on a first PAH therapy (index date) were identified from Optum's de-identified Clinformatics Data Mart Database (1/1/2010-12/31/2019). A random survival forest algorithm was developed using patient-month data and predicted the "survival function" (i.e. risk of not having unsatisfactory response) over time. For each patient-month observation, risk factors were assessed in the 12 months prior. Unsatisfactory response was defined as the first instance of (1) new PAH therapy, (2) PAH-related hospitalization or emergency room visit, (3) lung transplant or atrial septostomy, (4) PAH-related death or (5) chronic oxygen therapy initiation. To facilitate use in clinical practice, a simplified risk score was also developed based on a linear combination of the most important risk factors identified in the algorithm.

RESULTS

In total, 4781 patients were included (median age = 69.0 years; 58.6% female). Over a median follow-up of 14.0 months, 3169 (66.3%) had an unsatisfactory response. The most important risk factors included in the algorithm were healthcare resource use (i.e. PAH-related outpatient visits, pulmonologist visits, cardiologist visits, all-cause hospitalizations), time since first PAH diagnosis, time since index date, Charlson Comorbidity Index, dyspnea, and age. Predictive accuracy was good for the full algorithm (C-statistic: 0.732) but was slightly lower for the simplified risk score (C-statistic: 0.668).

CONCLUSION

The present claims-based algorithm performed well in predicting time to unsatisfactory response following initial PAH therapy.

Thermal sensitivity and seasonal change in the gut microbiome of a desert ant, Cephalotes rohweri

Microorganisms within ectotherms must withstand the variable body temperatures of their hosts. Shifts in host body temperature resulting from climate change have the potential to shape ectotherm microbiome composition. Microbiome compositional changes occurring in response to temperature in nature have not been frequently examined, restricting our ability to predict microbe-mediated ectotherm responses to climate change. In a set of field-based observations, we characterized gut bacterial communities and thermal exposure across a population of desert arboreal ants (Cephalotes rohweri). In a paired growth chamber experiment, we exposed ant colonies to variable temperature regimes differing by 5 °C for three months. We found that the abundance and composition of ant-associated bacteria were sensitive to elevated temperatures in both field and laboratory experiments. We observed a subset of taxa that responded similarly to temperature in the experimental and observational study, suggesting a role of seasonal temperature and local temperature differences amongst nests in shaping microbiomes within the ant population. Bacterial mutualists in the genus Cephaloticoccus (Opitutales: Opitutaceae) were especially sensitive to change in temperature-decreasing in abundance in naturally warm summer nests and warm growth chambers. We also report the discovery of a member of the Candidate Phlya Radiation (Phylum: Gracilibacteria), a suspected epibiont, found in low abundance within the guts of this ant species.

691 ‘ARE YOU CONCERNED ABOUT ME TODAY’ - AN MDT APPROACH TO IMPROVING DELIRIUM RECOGNITION

Introduction

Delirium is a common neuropsychiatric syndrome that increases the likelihood of adverse outcomes for patients admitted to hospital. Delirium is preventable and treatable. Recognition of the syndrome is challenging. Our aim was to increase this recognition through robust inpatient screening, utilising a multi-disciplinary team (MDT) approach.

Method

Stakeholder analysis for a quality improvement project revealed that junior doctors were members of the team most likely to perform a 4AT. Plan, do, study, act (PDSA) cycles were carried out: 1. Junior doctor engagement 2. Verbal prompts in huddle 3. Healthcare assistant (HCA) questionnaires.

Results

Baseline data showed that on average 0.6% patients had new 4AT over one week on elderly care wards. Intervention 1 involved 4AT handouts given to junior doctors. Number of 4ATs was 3% of patients per week. Intervention 2 used prompts in the morning MDT huddle, asking about concerns for patients. This increased the number of patients having 4AT per week to 6.5%. HCAs did not attend huddles and were targeted in the third intervention. A questionnaire with delirium information and the subsequent question ‘are you concerned about this patient’ was placed in patient bedside folders. This gave opportunity for HCAs to escalate patients to huddle so 4ATs could be carried out. The questionnaire was completed for 62% of patients, but only 1.4% patients were flagged up and subsequently had 4AT. This time was complicated however by the wards becoming Covid-19 wards.

Conclusion

Delirium is common however there is missed opportunity for earlier identification. Utilising HCAs with bedside questionnaires was time efficient and ensured robust escalation to prompt further investigation. When incorporated into huddle this could lead to more delirium diagnoses if carried out over a longer period, outside of the Covid-19 pandemic and on a ward solely populated with elderly care patients.

OP0255-PARE USING AN EDUCATIONAL APPLICATION TO FACILITATE UNDERSTANDING OF THE ANATOMY AND FUNCTION OF THE BRAIN AND TO EXPLORE THE EFFECTS OF CLINICAL FATIGUE FROM A PATIENT PERSPECTIVE

Background:

Rheumatic and musculoskeletal diseases are a group of devastating autoimmune disorders that all commonly share the debilitating symptom of fatigue. Despite the fact that fatigue can often cause some of the greatest impairments to quality of life, it is frequently reported by patients as the least successfully managed symptom of these conditions.

Fatigue is routinely misunderstood within the general population, with many people using the word fatigue as a synonym for tired. Fatigue is not the same as tiredness, which is a normal state that is experienced by most of the population, therefore it is important to help the general public understand what fatigue actually is and how it imposes consequences and limitations on those who suffer from it. To aid this understanding an educational application has been created to reinforce the patient perspective of living with fatigue. Furthermore, this application will also aid the understanding of brain anatomy and function, using Augmented Reality (AR), as research has now shown that brain function may be altered in the state of fatigue.

Currently, educational AR applications show great potential for increasing comprehension and understanding of complex concepts. AR expands user engagement by enhancing the learner’s enjoyment and enriching their learning environment. We hope to utilise this technology in the education of fatigue.

Objectives:

We aimed to create an AR application that has informative content designed to educate users on the topics of basic brain anatomy and function. Furthermore, we aimed to increase the users understanding of the complete impairment of fatigue by creating a short video that describes living with fatigue from the patient’s perspective.

Methods:

The application was created using medical scan dataset, a variety of 3D modelling software, and a game engine to create a functional and interactive augmented application. The short video regarding a patient’s perspective on living with fatigue was developed in collaboration with the Glasgow Arthritis Involvement Network patient partners. In order to determine if the application met its primary objectives a pilot test was conducted on 14 participants. After consenting to taking part in the study, individuals were guided through a pre-application test, the use of the application itself and finally a post-application test.

Results:

Initial results from the pilot test showed promise in the educational potential of the application. With regards to the questions pertaining to the brain anatomy, the percentage of questions answered correctly increased from 36% in the pre-test to 60% in the post-test. Furthermore, after using the application the participants reported a significant increase in their confidence for their answers. An additional six questions ascertained a participants perceptions of fatigue. From these questions, the answer that was most significantly changed after use of the application, was in relation to the impact that fatigue has on a patient’s quality of life (t-Test p=0.02). After use of the application participants’ opinions changed to reflect the fact that fatigue can completely impair a person’s quality of life, showing an increase in their understanding of the debilitating nature of fatigue.

Conclusion:

This research explored the development and effectiveness of an AR application that was centered around fatigue and basic neuroanatomy education within the general population. From the pilot test conducted we are able to report that the application was successful in delivering educational material about brain anatomy and was successful in increasing awareness about the impact that fatigue can have on an individual’s quality of life.

Figure 1.

Augmented brain model scene using brain model as trigger

Figure 2.

Example of material change upon selection of Occipital Lobe option

Acknowledgments:

The Glasgow Arthritis Involvement Network (GAIN)

Disclosure of Interests:

None declared

B-52 Improvements in Cognitive Functioning in Inactive Professional Fighters

Objective

Repetitive head injuries common in combat sports have been associated with increased risk for cognitive dysfunction. Interestingly, the Professional Fighter’s Brain Health Study (PFBHS) team has observed improvements in fighters’ cognitive performance following their transition to inactive fighting status. As this phenomenon was explored, it was hypothesized that fighters’ cognitive performance will initially improve following their discontinuation of fighting.

Methods

Longitudinal demographic, fighting history, and cognitive functioning data from 31 fighters who discontinued fighting during their participation in the PFBHS. Cognitive functioning was assessed via CNS Vital Signs and C3/iComet computerized batteries. Number of professional fights, as well as inactive fighting status, was determined using published professional online records. Fighters were considered inactive if they had gone two or more years without a professional match.

Results

Paired-samples t test was conducted to evaluate cognitive functioning in fighters at time 1 (actively fighting) and time 2 (inactive fighting status). When comparing cognitive function at across time points, performance on CNS Vital Signs measures of verbal memory, processing speed, psychomotor speed, and reaction time, as well as C3/iComet measures of set-shifting and complex reaction time, significantly improved at time 2 (all p’s < 0.05). Interestingly, performance did not improve across time points on a C3/iComet measure of processing speed (Trailmaking Test Part A).

Conclusions

Cognitive performance improved on most measures when fighters transitioned to inactive fighting status. Given the limited sample size, future analysis is necessary to evaluate the relationship between fighting status and cognitive performance in a larger sample size.

B-59 Prevalence of Pseudobulbar Affect Symptoms in Professional Fighters

Objective

Pseudobulbar Affect (PBA) is defined as dysregulation of emotional expression and is characterized by sudden, uncontrollable, laughing and/or crying that is discordant with the present mood or social context. This study sought to establish the prevalence of PBA symptoms in individuals with a high incidence of sports-related head injuries and explore the relationship between two rating scales designed to measure PBA symptoms.

Methods

Sixty-three professional fighters (age: M = 44.7, SD = 10.0; 98% male) underwent neurological and neuropsychological assessment including completion of the Pathological Laughing and Crying Scale (PLCS) and the Center for Neurologic Study – Lability Scale (CNS-LS). Diagnostic criteria for PBA were reviewed during the neurological exam to establish the prevalence of the clinical syndrome. Prevalence statistics for item endorsement on the rating scales and diagnostic status were calculated. To investigate the rate of agreement between rating scales, concordance correlation coefficient (CCC) and root mean square difference (RMSD) were calculated.

Results

Eleven percent of participants met clinical criteria for PBA diagnosis, 25% of participants endorsed clinically significant PBA symptoms on the CNS-LS (M = 10.9, SD = 4.9), and 8% endorsed significant symptoms on the PLCS (M = 3.1, SD = 6.5). The rating scales were significantly positively correlated (r = .58; p < .01), though overall agreement was low (CCC = 0.55; RMSD = 5.4).

Conclusions

This study demonstrates that the prevalence of PBA symptoms in a sample of professional fighters is not uncommon. Although both the CNS-LS and PCLS are designed to measure PBA symptoms, they appear to be measuring unique aspects of PBA that may provide complimentary, rather than redundant information.

C-03 The sensitivity and specificity of the Montreal Cognitive Assessment is Age Dependent for Amyloid Positivity in a Mixed Clinical Sample

Objective

The Montreal Cognitive Assessment (MoCA) is a widely-used screening tool for neurodegenerative disorders. Despite widespread use, there have been few investigations into correlations between MoCA and biomarkers of Alzheimer's disease pathology. This study examined the relationship between MoCA performance and the presence of amyloid as detected by positron emission tomography (PET).

Methods

Sensitivity and specificity for the total MoCA score were determined for 76 individuals (26 amyloid-negative, 50 amyloid- positive) who were between the ages of 55 and 90 and diagnosed with MCI or mild dementia with a CDR score of 0-1 and were participating in a longitudinal, observational study at the Cleveland Clinic Lou Ruvo Center for Brain Health. All individuals underwent an amyloid PET scan and cognitive screening.

Results

Sensitivity and specificity for the total score were determined using amyloid positivity as the standard. A cutpoint of 25 yielded the best balance between sensitivity and specificity (74% and 74%, respectively). A total score of 27 was required to achieve 90% sensitivity to identify amyloid positive individuals (i.e. only a 10% risk that individuals with a score of 28-30 have a positive scan). A score of 26 was required in individuals over the age of 75.

Conclusions

With the emergence of new diagnostic biomarkers, there is need to define the utility of affordable, widely-available screening tools. In this mixed clinical sample, the MoCA score showed good sensitivity for detecting amyloid pathology but with low specificity. Thus a total MoCA score of 28 is needed to confidently rule out risk for AD pathology.

C-02 An Unbiased Biomarker Approach to Neuropsychological, Behavioral, and Psychiatric Symptoms in a Mixed Clinical Sample

Objective

Suspected Non-Alzheimer’s Pathology (SNAPs) are individuals who present with a cognitive syndrome meeting clinical criteria for Alzheimer’s disease (AD) but are found to lack underlying AD pathology. Current clinical criteria for AD lack specificity in predicting underlying neurodegenerative pathology. With the advent of amyloid positron emission tomography (PET) the presence of amyloid pathology can now be identified in vivo. Using a biomarker-based approach, we aimed to characterize the neuropsychological, behavioral, and psychiatric profile of SNAPs in contrast to those with AD pathology (APs).

Method

76 individuals (26 amyloid-negative [SNAPs], 50 amyloid- positive [APs]) completed neuropsychological testing and a PET amyloid scan as a part of a longitudinal observational study at the Cleveland Clinic LRCBH. Individuals meeting NIA-A criteria for MCI or mild AD with a Clinical Dementia Rating score of .05 -1 were included. Amyloid status was determined via clinical read of two clinicians trained in reading amyloid scans (neuroradiologist and neuropsychiatrist). Independent samples t tests assessed group differences between SNAPs and APs across cognitive, behavioral, and psychiatric measures.

Results

Mini-Mental State Examination scores were equivalent between SNAPs and APs. SNAPs performed significantly better on measures of verbal and nonverbal memory, set-shifting, and semantic fluency, as well as aspects of processing speed and working memory (all p’s < .05). Additionally, SNAPs endorsed more RBD symptoms (p < .05). No significant group differences were observed across neuropsychiatric or functional measures.

Conclusion(s)

Differences in an individual’s neuropsychological, behavioral, and psychiatric profile in consideration with a biomarker approach may provide key insights and afford greater diagnostic clarity.

Relationship Between Verbal Fluency Performance, Fight Exposure, and Subcortical Region Brain Volumes in Professional Fighters

Purpose

Verbal fluency performance has been shown to be sensitive to preclinical cognitive changes in neurodegenerative diseases and may detect early, trauma-related cognitive and volumetric changes amongst professional fighters. Baseline verbal fluency performance and volumes of relevant subcortical brain structures were expected to decline as number of professional fights (NoPF) increased, while controlling for education.

Methods

Baseline letter and semantic fluency performance, NoPF, and structural brain imaging from 548 active and retired fighters who participated in the Professional Fighters Brain Health Study were considered. ANCOVAs were conducted to assess differences in verbal fluency performance by NOPF, while controlling for years of education. Number of professional fights were stratified into low (0-20 fights), medium (21-40 fights), and high (41 or more fights).

Results

Semantic fluency performance differed across the three levels of NoPF (F(2, 542)=4.56; p<.02). In addition, significant positive correlations between semantic fluency performance and volumes in the following regions were observed: left thalamus, left putamen, left pallidum, bilateral caudates, bilateral amygdalae, bilateral hippocampi, and bilateral accumbens (all p’s<.05). In contrast, letter fluency performance was not significantly associated with NoPF or volumes of relevant subcortical brain structures (all p’s>.05).

Conclusion

Semantic fluency may be low-cost, easy-to-administer harbinger of emerging cognitive dysfunction and lower volumes in related subcortical brain regions. Additional assessment of clinical utility is necessary.

Abstract P3-10-13: Dual targeting of androgen receptor and IKK alpha is a potential therapeutic strategy for triple negative breast cancer

Background

There are limited treatments for triple negative breast cancer (TNBC) patients and an unmet need for targeted approaches in these patients. In the last 4-5 years, the prevalence of high androgen receptor (AR) expression in TNBCs has been noted in up to 50% of tumors suggesting it has clinical relevance. The non-canonical NF-kB pathway is also upregulated in this patient group and it has been reported that that there is crosstalk between these pathways. Therefore the aim of this study was to examine the expression of IKKα and AR in breast cancer tissue samples, to assess if combining these markers increased prognostic power.

Methods

Immunohistochemistry was performed on tissue microarray of 410 patients to assess proteins level of IKK alpha and AR. Protein expression levels were assessed using the weighted histoscore (WHS) method. The median was employed as the cut off for IKK alpha and 1% as cut off for AR. Expression was analyzed for associations with cancer-specific survival (CSS) and recurrence-free survival (RFS).

Results

In a cohort of 370 breast cancers nether AR nor IKK alpha alone or combined were associated with CSS or RFS. Stratifying patients by ER status did not impact CSS or RFS. However, in TNBC patients (n=82) high expression of AR was associated with shorter CSS (HR 2.55 95 CI 1.61-5.59, p=0.013). To assess if combining AR and IKK alpha increased prognostic power, AR and IKK alpha were combined into a single score: 0= low expression of both or high expression of one and 1= high expression of both. In the full cohort or when stratified by ER status the score was not associated with CSS or RFS, however in TNBC the combined score potentiated the effect observed with AR alone, (HR 1.68 95 CI 1.20-2.33, p=0.001). Patient CSS was stratified from 11.5 years to 4.6 years and was independently associated with CSS when compared with common clinicopathological factors (HR 1.56 95CI 1.11-2.21, p=0.011). In addition, the combined score was associated with decrease radiotherapy use (p=0.032), increased recurrence rate (p=0.014), decreased cytotoxic T cells (p=0.007), B cells (p=0.043) and macrophages (p=0.037).

Conclusions

A combined AR and IKK alpha score is an independent prognostic classification for patients with TNBC. Patients with high expression of both AR and IKK alpha a significantly reduced survival and were immune cell cold. This study suggests that this patient group will not benefit from immunotherapy but dual targeting with anti-androgens and IKK alpha selective inhibitors could offer a novel therapeutic strategy for this patient group.

Citation Format: Roseweir AK, Khongthong P, Dickson K, Bennett L, Edwards J. Dual targeting of androgen receptor and IKK alpha is a potential therapeutic strategy for triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-10-13.

A NEW SEMI-EMPIRICAL AMBIENT TO EFFECTIVE DOSE CONVERSION MODEL FOR THE PREDICTIVE CODE FOR AIRCREW RADIATION EXPOSURE (PCAIRE)

The Predictive Code for Aircrew Radiation Exposure (PCAIRE) is a semi-empirical code that estimates both ambient dose equivalent, based on years of on-board measurements, and effective dose to aircrew. Currently, PCAIRE estimates effective dose by converting the ambient dose equivalent to effective dose (E/H) using a model that is based on radiation transport calculations and on the radiation weighting factors recommended in International Commission on Radiological Protection (ICRP) 60. In this study, a new semi-empirical E/H model is proposed to replace the existing transport calculation models. The new model is based on flight data measured using a tissue-equivalent proportional counter (TEPC). The measured flight TEPC data are separated into a low- and a high-lineal-energy spectrum using an amplitude-weighted ¹³⁷Cs TEPC spectrum. The high-lineal-energy spectrum is determined by subtracting the low-lineal-energy spectrum from the measured flight TEPC spectrum. With knowledge of E/H for the low- and high-lineal-energy spectra, the total E/H is estimated for a given flight altitude and geographic location. The semi-empirical E/H model also uses new radiation weighting factors to align the model with the most recent ICRP 103 recommendations. The ICRP 103-based semi-empirical effective dose model predicts that there is a ∼30 % reduction in dose in comparison with the ICRP 60-based model. Furthermore, the ambient dose equivalent is now a more conservative dose estimate for jet aircraft altitudes in the range of 7-13 km (FL230-430). This new semi-empirical E/H model is validated against E/H predicted from a Monte Carlo N-Particle transport code simulation of cosmic ray propagation through the Earth's atmosphere. Its implementation allows PCAIRE to provide an accurate semi-empirical estimate of the effective dose.

Pregnancy outcomes in cystic fibrosis: a 10-year experience from a UK centre

BACKGROUND

Cystic fibrosis manifests as a multisystem disease, despite this female fertility is relatively preserved with levels approaching that of the non-cystic fibrosis population. We reviewed pregnancies in cystic fibrosis patients over a 10-year period from a UK adult cystic fibrosis centre by considering maternal and fetal outcomes.

METHODS

We conducted a retrospective case-note review of pregnancies during 2003-2013 using respiratory and obstetric records.

RESULTS

We observed moderate falls in lung function immediately after delivery, which persisted at 12 months postpartum. We found that a decline in lung function at delivery was a marker for further decline in function during the subsequent postpartum period. We found baseline lung function was predictive of gestational age at delivery. We observed a high incidence of haemoptysis.

CONCLUSION

Consistent with current guidance we found pregnancy is feasible and well tolerated in the majority of patients with cystic fibrosis. There was a high incidence of haemoptysis, which warrants further study.

An inpatient observation and comparison of the bennett's I.p.p.R. And aerosol methods of administering salbutamol

Compared with aerosol administration the Bennett's Intermittent Positive Pressure Respirator (I.P.P.R.) has been the most favoured method of Salbutamol administration in hospitals for the treatment of asthma or Chronic Obstructive Airways Disease (C.O.A.D.).

NFκB signalling is upregulated in a subset of castrate-resistant prostate cancer patients and correlates with disease progression

BACKGROUND

Cell line models suggest that activation of NFκB is associated with progression of prostate cancer. This pathway may be a therapeutic target if these observations translate to clinical specimens.

METHODS

Immunohistochemistry measured NFκBp65 (p65), NFκBp65 nuclear localisation signal (NLS), NFκBp65 phosphorylated at ser 276 (p65(ser276)), NFκBp65 phosphorylated at ser 536 (p65(ser536)), IκBα phosphorylated at ser 32/36 (pIκBα(ser32/36)) and MMP-9 protein expression in 61 matched hormone naive prostate cancer (HNPC) and castrate-resistant prostate cancer (CRPC) tumours. Animal and cell models were used to investigate the role of NFκB inhibition in prostate carcinogenesis.

RESULTS

In HNPC tumours, NLS expression significantly associated with a shorter time to disease recurrence and disease-specific death. In CRPC tumours p65, pIκBα(ser32/36) and MMP-9 expression significantly associated with shorter time to death from disease recurrence and shorter disease-specific death. MMP-9 and pIκBα(ser32/36) expression significantly associated with metastases at recurrence and were independent of Gleason sum and prostate-specific antigen at recurrence. Expression of phosphorylated Akt was associated with increased p65 activation in mouse models and inhibition of NFκB in LNCaP cells significantly reduced cellular proliferation and induced apoptosis.

CONCLUSION

These results provide further evidence that the NFκB pathway could be exploited as a target for CRPC.

CURRENT PRACTICE IN RENAL ANAEMIA MANAGEMENT: TWO MULTINATIONAL SURVEYS

The European Best Practice Guidelines recommend that 85% of patients with standard causes of chronic renal failure should achieve a target haemoglobin concentration of > or = 11 g/dL. However, patient outcomes need to be improved as many patients respond suboptimally to treatment and fail to reach these targets. Two multinational surveys of nursing practice in the management of renal anaemia in northern (with comparative data from Australia) and southern Europe were conducted. The aim was to assess variations in the role and amount of responsibility delegated to nurses in renal units throughout Europe and Australia. Patient care could be optimised by developing formal training and educational programmes for nephrology nurses and this has already occurred in many units in the UK.

Health-related quality of life in patients with metastatic colorectal cancer treated with panitumumab in first- or second-line treatment

Background:

Panitumumab in combination with chemotherapy was evaluated in two pivotal clinical trials in first- and second-line treatment of metastatic colorectal cancer (mCRC), respectively. This analysis compared the health-related quality of life (HRQoL) of patients with or without panitumumab in the two trials.

Methods:

Patients with mCRC were randomised to FOLFOX (first-line trial) or FOLFIRI (second-line trial)±panitumumab. The EuroQoL 5-Dimensions Health State Index (EQ-5D HSI) and Visual Analogue Scale (EQ-5D VAS) were assessed at baseline and monthly follow-up until disease progression. Patients with wild-type KRAS mCRC with baseline and post-baseline HRQoL scores were included. Difference in change from baseline between treatment groups was evaluated using linear mixed and pattern-mixture models.

Results:

In the first-line trial, 576 patients with wild-type KRAS mCRC (284 panitumumab+FOLFOX4 and 292 FOLFOX4 alone) were included in the HRQoL analyses. In the second-line trial, 530 patients with wild-type KRAS mCRC were included in these analyses (263 panitumumab+FOLFIRI and 267 FOLFIRI alone). There was no significant difference in the change in EQ-5D HSI and VAS scores between treatment groups in either trial.

Conclusion:

The addition of panitumumab to FOLFOX4 or FOLFIRI in first- or second-line treatment of wild-type KRAS mCRC significantly improved progression-free survival without compromising HRQoL.

Establishment of an HIV/sexually transmitted disease programme and prevalence of infection among incarcerated men in Jamaica

The goal of this study is to describe the establishment of an HIV testing and treatment programme in the Jamaican correctional system and to estimate the prevalence of HIV/sexually transmitted disease (STD) among adult incarcerated men in this country. A demonstration project was implemented by the Jamaican Department of Correctional Services and Ministry of Health in the nation's largest correctional centre. All inmates were offered HIV and syphilis testing, and a subset was offered chlamydia, gonorrhoea and trichomoniasis testing. Cross-sectional data from the project were reviewed to determine the prevalence and correlates of HIV/STD. HIV test acceptance was 63% for voluntary testers (n = 1200). The prevalence of HIV was 3.3% (95% confidence interval [CI] 2.33-4.64) (n = 1017) and the prevalence syphilis was 0.7% (95% CI 0.29-1.49) (n = 967). Among the subset tested (n = 396) the prevalence of chlamydia was 2.5% (95% CI 1.22-4.49) and for trichomoniasis it was 1.8% (95% CI 0.01-3.60), but no cases of gonorrhoea were detected (n = 396). The prevalence of HIV was significantly higher at 25% (95% CI 13.64-39.60) for persons located in a separate section where individuals labelled as men who have sex with men (MSM) are separated. HIV/STD testing is important and feasible in Jamaica. A special focus should be placed on providing services to inmates labelled as MSM. Other Caribbean nations may also benefit from similar programmes.

Comparison of codes assessing galactic cosmic radiation exposure of aircraft crew

The assessment of the exposure to cosmic radiation onboard aircraft is one of the preoccupations of bodies responsible for radiation protection. Cosmic particle flux is significantly higher onboard aircraft than at ground level and its intensity depends on the solar activity. The dose is usually estimated using codes validated by the experimental data. In this paper, a comparison of various codes is presented, some of them are used routinely, to assess the dose received by the aircraft crew caused by the galactic cosmic radiation. Results are provided for periods close to solar maximum and minimum and for selected flights covering major commercial routes in the world. The overall agreement between the codes, particularly for those routinely used for aircraft crew dosimetry, was better than +/-20 % from the median in all but two cases. The agreement within the codes is considered to be fully satisfactory for radiation protection purposes.

Renal anaemia: recent developments and future directions for improved management

The global burden of chronic kidney disease (CKD) and associated anaemia is substantial. With the increasing numbers of patients that are likely to be affected in the future, approaches are required to improve anaemia management without increasing the workload of renal units. Advocating early treatment may improve patient outcomes and nurses are in an ideal position to identify and manage anaemia at an early stage in patients with CKD. In addition, adopting a multidisciplinary approach, alongside nephrologists, diabetologists, cardiologists, social workers, nutritionists and pharmacists, may allow nurses to detect and treat anaemia earlier in patients with CKD. Maintaining awareness of factors associated with decreased erythropoiesis-stimulating agents (ESAs) efficacy (e.g. iron deficiency or poor nutritional status) is also important. To reduce the burden on healthcare providers, anaemia management could be simplified by extending the administration interval of ESAs. Recent studies have explored the clinical efficacy of administration of currently available agents at intervals of up to once monthly in highly selected, stable patients. The use of an ESA that can control anaemia while maintaining haemoglobin levels within guideline ranges with extended administration intervals in all patients without the need for additional screening or stepwise dose adjustments with attendant monitoring may help improve patient care while reducing the workload of healthcare providers.

A patient follow-up survey programme for alosetron: assessing compliance to and effectiveness of the risk management programme

BACKGROUND

In November 2002, alosetron HCl (Lotronex, GlaxoSmithKline Research Triangle Park, NC, USA) was re-introduced to the US marketplace for women with severe diarrhoea-predominant irritable bowel syndrome. In support of the re-introduction, a risk management programme was implemented, which included a patient follow-up study in which all users of alosetron could participate.

AIM

We report on the methods used and the effectiveness of key elements of the risk management programme.

METHODS

Patients voluntarily enroled in the study and completed questionnaires at baseline, after 5 and 10 weeks, and quarterly thereafter. Questions focussed on patient eligibility, knowledge of risks and benefits, and adherence to the recommended programme elements for education, prescribing and dispensing.

RESULTS

Between December 2002 and 2004, 4,803 patients enrolled in the study, and <3% were lost to follow-up. The average follow-up time was approximately 6 months, and the response rate for each assessment was >95%. A total of 90% of patients at baseline met the full clinical criteria recommended for the treatment. Patient adherence to the risk management programme was >87%.

CONCLUSIONS

Using the Lotronex risk management programme, patients met clinical criteria, were knowledgeable about treatment risks and benefits, and were adherent to the process elements of the programme. These patients seemed to engage in active dialogue with their physicians about symptoms and use of alosetron.

Twice-weekly administration of peginterferon-alpha-2b improves viral kinetics in patients with chronic hepatitis C genotype 1

The decline in hepatitis C viral load on treatment with peginterferon-alpha-2b is not continuous. The aim of this study was to investigate whether twice weekly dosing of peginterferon-alpha-2b may improve viral kinetics. Ten interferon-naïve patients with chronic hepatitis C (genotype 1a or b) were randomized to receive either 1.0 microg/kg peginterferon-alpha-2b once (group A) or twice weekly (group B) for 4 weeks. Viral load and serum concentrations of peginterferon-alpha-2b were measured. Peginterferon-alpha-2b reached maximal blood concentrations 24 h after the first dose, followed by a linear decline during the subsequent days. On the day before administration of the next dose, peginterferon-alpha-2b was undetectable in nine patients in group A (once weekly dosing). The same pattern was observed during the next 3 weeks of therapy. In group B (twice weekly dosing) peginterferon-alpha-2b was detectable at any given time point and higher than in group A (P between 0.01 and <0.0001). Viral load decreased in all patients within 2 days after the first dose of peginterferon-alpha-2b, but increased again on day 3. In group A, it further increased until day 7. A similar pattern was observed in the second week. In contrast, in group B, viral load decreased again on day 4 and remained lower until the end of the study (P < 0.001). To achieve continuous drug exposure and to improve initial viral clearance, peginterferon-alpha-2b has to be given at least two times weekly.

Insulin-like growth factor-1 inscribes a gene expression profile for angiogenic factors and cancer progression in breast epithelial cells

Activation of the insulin-like growth factor-1 receptor (IGF-1R) by IGF-1 is associated with the risk and progression of many types of cancer, although despite this it remains unclear how activated IGF-1R contributes to cancer progression. In this study, gene expression changes elicited by IGF-1 were profiled in breast epithelial cells. We noted that many genes are functionally linked to cancer progression and angiogenesis. To validate some of the changes observed, the RNA and/or protein was confirmed for c-fos, cytochrome P450 1A1, cytochrome P450 1B1, interleukin-1 beta, fas ligand, vascular endothelial growth factor, and urokinase plasminogen activator. Nuclear proteins were also temporally monitored to address how gene expression changes were regulated. We found that IGF-1 stimulated the nuclear translocation of phosphorylated AKT, hypoxic-inducible factor-1 alpha, and phosphorylated cAMP-responsive element-binding protein, which correlated with temporal changes in gene expression. Next, the promoter regions of IGF-1-regulated genes were searched in silico. The promoters of genes that clustered together had similar regulatory regions. In summary, IGF-1 inscribes a gene expression profile relevant to cancer progression, and this study provides insight into the mechanism(s) whereby some of these changes occur.

Assessing gene significance from cDNA microarray expression data via mixed models

The determination of a list of differentially expressed genes is a basic objective in many cDNA microarray experiments. We present a statistical approach that allows direct control over the percentage of false positives in such a list and, under certain reasonable assumptions, improves on existing methods with respect to the percentage of false negatives. The method accommodates a wide variety of experimental designs and can simultaneously assess significant differences between multiple types of biological samples. Two interconnected mixed linear models are central to the method and provide a flexible means to properly account for variability both across and within genes. The mixed model also provides a convenient framework for evaluating the statistical power of any particular experimental design and thus enables a researcher to a priori select an appropriate number of replicates. We also suggest some basic graphics for visualizing lists of significant genes. Analyses of published experiments studying human cancer and yeast cells illustrate the results.

Patient falls from bed and the role of bedrails in the acute care setting

The use of bedrails in preventing patient falls from bed remains highly controversial and has received only limited research attention throughout the last decade. The present study questioned the relationship between bedrail use and patient falls from bed particularly in terms of age-gender characteristics, mental status and the severity of injuries sustained. A retrospective, cross-sectional analysis was conducted of 419 patient falls occurring in an urban, acute care hospital from 1993-2000. This audit identified 136 falls from bed. It was found that for all age-gender groups the incidence of falls from bed with bedrails elevated was equal to or higher than when bedrails were not elevated. Patients in a 'non rational' state at the time of falling were significantly more likely to have fallen with the bedrails elevated (chi 2 = 19.463, p < 0.001). Whilst there was no statistically significant relationship between the position of bedrails and the severity of injuries sustained (chi 2 = 1.088, p = 0.780) the fact that there was a patient death resulting from a fall from bed over elevated bedrails was considered to be of particular clinical significance. Thus the role of bedrails as protective or safety devices was challenged and an urgent re-evaluation of current practices recommended.

Improving the nurse-patient relationship: a multi-faceted approach

AIM

A Corporate Education Session was held to provide concrete strategies for overcoming several specific barriers in the daily nurse-patient relationship that negatively affect the patient, nurse, or both, and to provide the latest information about best practice as it affects nurses in renal care.

METHODOLOGY

The session was led by a moderator who presented three video case studies to the audience. Communication strategies for recognising and overcoming nurse-patient communication barriers were presented. The audience expressed their views about each case study using voting pads, and a panel of experts addressed the comments of the audience and discussed guidelines for best practice in renal care. The panel comprised three experienced renal nurses, a senior nephrologist, and an expert in social interaction.

CONCLUSIONS

Optimal treatment of patients with renal disease should include early treatment of anaemia, adequate levels of dialysis, and a multidisciplinary approach, responding to both the medical and the social needs of the patient.

MAPS: a microarray project system for gene expression experiment information and data validation

SUMMARY

MAPS is a MicroArray Project System for management and interpretation of microarray gene expression experiment information and data. Microarray project information is organized to track experiments and results that are: (1) validated by performing analysis on stored replicate gene expression data; and (2) queried according to the biological classifications of genes deposited on microarray chips.