Neutralization escape of Omicron XBB, BR.2, and BA.2.3.20 subvariants

New Omicron subvariants continue to emerge throughout the world. In particular, the XBB subvariant, which is a recombinant virus between BA.2.10.1.1 and BA.2.75.3.1.1.1, as well as the BA.2.3.20 and BR.2 subvariants that contain mutations distinct from BA.2 and BA.2.75, are currently increasing in proportion of variants sequenced. Here we show that antibodies induced by 3-dose mRNA booster vaccination as well as BA.1- and BA.4/5-wave infection effectively neutralize BA.2, BR.2, and BA.2.3.20 but have significantly reduced efficiency against XBB. In addition, the BA.2.3.20 subvariant exhibits enhanced infectivity in the lung-derived CaLu-3 cells and in 293T-ACE2 cells. Overall, our results demonstrate that the XBB subvariant is highly neutralization resistant, which highlights the need for continued monitoring of the immune escape and tissue tropism of emerging Omicron subvariants.

Enhanced evasion of neutralizing antibody response by Omicron XBB.1.5, CH.1.1, and CA.3.1 variants

Omicron subvariants continuingly challenge current vaccination strategies. Here, we demonstrate nearly complete escape of the XBB.1.5, CH.1.1, and CA.3.1 variants from neutralizing antibodies stimulated by three doses of mRNA vaccine or by BA.4/5 wave infection, but neutralization is rescued by a BA.5-containing bivalent booster. CH.1.1 and CA.3.1 show strong immune escape from monoclonal antibody S309. Additionally, XBB.1.5, CH.1.1, and CA.3.1 spike proteins exhibit increased fusogenicity and enhanced processing compared with BA.2. Homology modeling reveals the key roles of G252V and F486P in the neutralization resistance of XBB.1.5, with F486P also enhancing receptor binding. Further, K444T/M and L452R in CH.1.1 and CA.3.1 likely drive escape from class II neutralizing antibodies, whereas R346T and G339H mutations could confer the strong neutralization resistance of these two subvariants to S309-like antibodies. Overall, our results support the need for administration of the bivalent mRNA vaccine and continued surveillance of Omicron subvariants.

The development and validation of a new simulator for endourology

INTRODUCTION

Simulation in medicine has developed a lot in the last few decades. There is a broad range of simulators available, above all for training in surgical procedures. Endourology can benefit much from simulation because the minimally-invasive procedures of endourology frequently have long learning curves, which can be reduced by training with simulators.

MATERIALS AND METHODS

A low-fidelity simulator was designed for practicing endourology techniques that use cystoscopy. The process of validation involved 5 experts and 19 non-experts. Experts comprised medical professionals working in a department of urology who had performed at least 100 flexible cystoscopy procedures. Non-experts were residents in internal medicine without experience in any type of endoscopy. Information about face and content validity was collected by means of Likert scales from 1 to 5. To evaluate construct validity, we measured the time to complete two tasks, for which the procedure was evaluated by means of the OSATS global evaluation scale.

RESULTS

New simulator was successfully built according to its design. For all evaluated aspects of construct validity, there was a significant difference (p<0.05) between the group of experts and the group of non-experts. Content validity was scored 4.66 (standard deviation ±0.56) by the experts and 4.41 (±0.71) by the non-experts. In the face validity questionnaire, the average score was 4.14 (±0.94), the question receiving the highest score: 4.6 (±0.84) concerned immersion in the procedure.

CONCLUSION

The simulator presented is valid both for training up new urologists in endourology technique and for experts seeking to perfect their skills.

Extraordinary Evasion of Neutralizing Antibody Response by Omicron XBB.1.5, CH.1.1 and CA.3.1 Variants

Newly emerging Omicron subvariants continue to emerge around the world, presenting potential challenges to current vaccination strategies. This study investigates the extent of neutralizing antibody escape by new subvariants XBB.1.5, CH.1.1, and CA.3.1, as well as their impacts on spike protein biology. Our results demonstrated a nearly complete escape of these variants from neutralizing antibodies stimulated by three doses of mRNA vaccine, but neutralization was rescued by a bivalent booster. However, CH.1.1 and CA.3.1 variants were highly resistant to both monovalent and bivalent mRNA vaccinations. We also assessed neutralization by sera from individuals infected during the BA.4/5 wave of infection and observed similar trends of immune escape. In these cohorts, XBB.1.5 did not exhibit enhanced neutralization resistance over the recently dominant BQ.1.1 variant. Notably, the spike proteins of XBB.1.5, CH.1.1, and CA.3.1 all exhibited increased fusogenicity compared to BA.2, correlating with enhanced S processing. Overall, our results support the administration of new bivalent mRNA vaccines, especially in fighting against newly emerged Omicron subvariants, as well as the need for continued surveillance of Omicron subvariants.

Enhanced neutralization resistance of SARS-CoV-2 Omicron subvariants BQ.1, BQ.1.1, BA.4.6, BF.7, and BA.2.75.2

The continued evolution of SARS-CoV-2 has led to the emergence of several new Omicron subvariants, including BQ.1, BQ.1.1, BA.4.6, BF.7, and BA.2.75.2. Here, we examine the neutralization resistance of these subvariants against sera from 3-dose vaccinated healthcare workers, hospitalized BA.1-wave patients, and BA.4/5-wave patients. We found enhanced neutralization resistance in all new subvariants, especially in the BQ.1 and BQ.1.1 subvariants driven by N460K and K444T mutations, as well as the BA.2.75.2 subvariant driven largely by its F486S mutation. All Omicron subvariants maintained their weakened infectivity in Calu-3 cells, with the F486S mutation driving further diminished titer for the BA.2.75.2 subvariant. Molecular modeling revealed the mechanisms of antibody-mediated immune evasion by R346T, K444T, F486S, and D1199N mutations. Altogether, these findings shed light on the evolution of newly emerging SARS-CoV-2 Omicron subvariants.

Enhanced neutralization resistance of SARS-CoV-2 Omicron subvariants BQ.1, BQ.1.1, BA.4.6, BF.7, and BA.2.75.2

The continued evolution of SARS-CoV-2 has led to the emergence of several new Omicron subvariants, including BQ.1, BQ.1.1, BA.4.6, BF.7, and BA.2.75.2. Here, we examine the neutralization resistance of these subvariants against sera from 3-dose vaccinated healthcare workers, hospitalized BA.1-wave patients, and BA.4/5-wave patients. We found enhanced neutralization resistance in all new subvariants, especially in the BQ.1 and BQ.1.1 subvariants driven by N460K and K444T mutations, as well as the BA.2.75.2 subvariant driven largely by its F486S mutation. All Omicron subvariants maintained their weakened infectivity in Calu-3 cells, with the F486S mutation driving further diminished titer for the BA.2.75.2 subvariant. Molecular modeling revealed the mechanisms of antibody-mediated immune evasion by R346T, K444T, F486S, and D1199N mutations. Altogether, these findings shed light on the evolution of newly emerging SARS-CoV-2 Omicron subvariants.

CTIM-09. ENRICHED TCR/BCR VDJ REARRANGEMENTS CORRELATE WITH MRI AND SURVIVAL OUTCOMES IN PATIENTS WITH RECURRENT HIGH-GRADE GLIOMA TREATED WITH CAN-3110

BACKGROUND

CAN-3110 (rQNestin34.5v2) is an HSV-1 oncolytic viral immunotherapy with one copy of the inflammatory ICP34.5 gene under transcriptional control of the Nestin glioma-specific promoter. We completed a phase 1 sequential dose-escalation trial of CAN-3110 in recurrent high-grade glioma (rHGG).

METHODS

CAN-3110 was injected intratumorally starting at 1x106 plaque forming units (pfu) and dose- escalated by half log up to 1x1010 pfu in biopsy confirmed rHGG. An expansion cohort of 12 patients was then accrued at 1x109 pfus. Blood and post-injection rHGG were collected.

RESULTS

41 rHGG patients were treated (42 separate interventions): median age 56 years (range 27-74); 21 females, 20 males; median baseline KPS 90 (range 70-100). CAN-3110 administration was well-tolerated with no dose limiting toxicities. Median overall survival (mOS) was 11.9 months. Histologic and molecular analyses showed significantly increased T cell infiltration in post treatment samples with elevated T cell and/or B cell receptor (TCR/BCR) transcripts which correlated with patient survival (HR 0.26 for patients with elevated TCR/BCR rearrangements as compared to patients with low). Volumetric analyses of MRI suggest a trend between reduction in the relative change in tumor growth, TCR/BCRs enrichment and survival in CAN-3110 treated patients.

CLINICAL IMPLICATIONS

Administration of CAN-3110 into rHGG was well tolerated. OS of CAN-3110 treated subjects compare favorably to historical controls. The association of increased TCR/BCR transcripts with survival suggests that CAN-3110 induces T cell responses against rHGG, supporting further clinical development of CAN-3110 viral immunotherapy.

Distinct Neutralizing Antibody Escape of SARS-CoV-2 Omicron Subvariants BQ.1, BQ.1.1, BA.4.6, BF.7 and BA.2.75.2

Continued evolution of SARS-CoV-2 has led to the emergence of several new Omicron subvariants, including BQ.1, BQ. 1.1, BA.4.6, BF.7 and BA.2.75.2. Here we examine the neutralization resistance of these subvariants, as well as their ancestral BA.4/5, BA.2.75 and D614G variants, against sera from 3-dose vaccinated health care workers, hospitalized BA.1-wave patients, and BA.5-wave patients. We found enhanced neutralization resistance in all new subvariants, especially the BQ.1 and BQ.1.1 subvariants driven by a key N460K mutation, and to a lesser extent, R346T and K444T mutations, as well as the BA.2.75.2 subvariant driven largely by its F486S mutation. The BQ.1 and BQ.1.1 subvariants also exhibited enhanced fusogenicity and S processing dictated by the N460K mutation. Interestingly, the BA.2.75.2 subvariant saw an enhancement by the F486S mutation and a reduction by the D1199N mutation to its fusogenicity and S processing, resulting in minimal overall change. Molecular modelling revealed the mechanisms of receptor-binding and non-receptor binding monoclonal antibody-mediated immune evasion by R346T, K444T, F486S and D1199N mutations. Altogether, these findings shed light on the concerning evolution of newly emerging SARS-CoV-2 Omicron subvariants.

P15.04.B Serial18F-fluciclovine PET-CT and multiparametric MRI during chemoradiation for glioblastoma - an exploratory clinical study with pre-clinical correlation

Background

Positron emission tomography (PET) using anti-1-amino-3-18fluorine-fluorocyclobutane-1-carboxylic acid (18F-fluciclovine) shows preferential glioma cell uptake with low activity in normal brain. Dynamic contrast-enhanced (DCE) MRI may also be used to investigate regions of glioma that do not show gadolinium-enhancement on post-contrast T1-weighted MR sequences (Gd-T1) and may reflect tumour infiltration beyond the Gd-T1 enhancing margin. There is a paucity of data on how 18F-fluciclovine uptake correlates with Gd-T1 and DCE-MRI activity, how it correlates with tumour biology and whether significant changes in uptake occur during treatment. The aims of this pilot study were: 1 To compare 18F-fluciclovine PET, DCE-MRI and Gd-T1 in patients undergoing chemoradiotherapy for glioblastoma (GBM) 2 To investigate correlation between 18F-fluciclovine uptake, MRI findings, and tumour biology in a pre-clinical glioma model.

Material and Methods

18F-fluciclovine-PET-CT and MRI including DCE-MRI were acquired before, during and after adjuvant chemoradiotherapy (60 Gy in 30 fractions with temozolomide) in GBM patients. DCE-MRI and Gd-T1 volumes were manually contoured, and PET volumes defined using semi-automatic thresholding. Gd-T1 was subtracted from PET and DCE-MRI volumes to identify areas beyond the Gd-T1 volume boundary and similarity of the PET and DCE-MRI volumes outside the Gd-T1 volume boundary were measured using the Dice similarity coefficient (DSC). CT-2A tumour cells were stereotactically injected into the right striatum of 8 to 10-week-old C57BL6J mice and they underwent MRI and 18F-fluciclovine PET-CT. Post-mortem mice brains underwent immunohistochemistry staining for ASCT2 (amino acid transporter), nestin (stemness) and Ki-67 (proliferation) to assess for biologically active tumour.

Results

6 patients were recruited (GBM 1-6). For GBM 1-3: PET volumes were greater than DCE-MRI, in turn greater than Gd-T1. For GBM 4-6, Gd-T1 volumes were similar to DCE-MRI and both were greater than PET volumes. GBM 1-3 had lower overall survival than GBM 4-6: median 249 vs. 903 days. 18F-fluciclovine uptake and Gd uptake (on DCE-MRI) was seen beyond the margins of the standard Gd-T1 volume. Comparing these regions beyond the Gd-T1 margins, the PET and DCE-MRI had low DSC, suggesting distinct areas of fluciclovine and DCE-MRI uptake. Pre-clinical PET-CT demonstrated tumour-specific 18F-fluciclovine uptake which corresponded to biologically active tumour based on immunostaining for Ki-67, nestin and ASCT2.

Conclusion

Results from this joint pre-clinical and clinical pilot study suggest volumes of 18F-fluciclovine-PET activity beyond that depicted by MRI-DCE and Gd-T1 are associated with a poorer prognosis in patients undergoing chemoradiotherapy for GBM. The pre-clinical model confirmed 18F-fluciclovine uptake reflected biologically active tumour.

[18F] Sodium Fluoride Dose Reduction Enabled by Digital Photon Counting PET/CT for Evaluation of Osteoblastic Activity

The aim of the study was to assess the quality and reproducibility of reducing the injected [¹⁸F] sodium fluoride ([¹⁸F]NaF) dose while maintaining diagnostic imaging quality in bone imaging in a preclinical skeletal model using digital photon counting PET (dPET) detector technology. Beagles (n = 9) were administered three different [¹⁸F]NaF doses: 111 MBq (n = 5), 20 MBq (n = 5), and 1.9 MBq (n = 9). Imaging started ≃45 min post-injection for ≃30 min total acquisition time. Images were reconstructed using Time-of-Flight, ultra-high definition (voxel size of 1 × 1 × 1 mm³), with 3 iterations and 3 subsets. Point spread function was modeled and Gaussian filtering was applied. Skeleton qualitative and quantitative molecular image assessment was performed. The overall diagnostic quality of all images scored excellent (61%) and acceptable (39%) by all the reviewers. [¹⁸F]NaF SUV_mean showed no statistically significant differences among the three doses in any of the region of interest assessed. This study demonstrated that a 60-fold [¹⁸F]NaF dose reduction was not significantly different from the highest dose, and it had not significant effect on overall image quality and quantitative accuracy. In the future, ultra-low dose [¹⁸F]NaF dPET/CT imaging may significantly decrease PET radiation exposure to preclinical subjects and personnel.

Myocardial ischaemia of non-obstructive origin as a cause of new onset anginal chest pain in the long COVID syndrome

Background

New-onset chest pain occurs in around 20% of patients with long COVID syndrome (LCS). Being the vascular endothelium one of the targets of the SARS-CoV-2 virus, we hypothesized that new onset anginal symptoms in LCS could be due to endothelium dysfunction and other non-obstructive causes of myocardial ischaemia.

Methods

We investigated 11 consecutive patients who developed new onset anginal chest pain, suggestive of myocardial ischaemia, after documented SARS-CoV-2 infection. Intracoronary assessment included endothelium-dependent evaluation with acetylcholine testing (Ach), and endothelium-independent assessment with coronary flow reserve (CFR) and microcirculatory resistance (MR). Criteria for positiveness of these tests and medical treatment recommendation were obtained from 2019 ESC guidelines and 2020 EAPCI consensus document on ischaemia with non-obstructive coronary arteries (INOCA).

Results

Mean patient age was 56 years (SD ± 15); 10 (91%) were female. In the acute COVID-19 phase, 4 patients (36%) had had pulmonary infiltrates and 2 (18%) required hospitalization. Conclusive non-invasive tests were obtained in 7 (64%), showing exercise-related myocardial ischaemia in 6 (86%). Coronary angiography ruled out obstructive epicardial stenoses in all the patients. Ach testing revealed abnormal endothelium-dependent responses in 9 (82%) patients: 5 (56%) had epicardial vessel and 4 (44%) microvascular spasm. Endothelium-independent assessment was abnormal in 6 (54%) cases, with abnormal CFR in 2 (33%), abnormal MR in 2 (33) and both abnormal CFR and MR in 2 (33%) patients. The most frequent endotype was combined endothelium dependent- and independent abnormalities (6/9, 67%). Stratified medical treatment according to endotype led to significant improvement in Seattle Angina Scores for angina frequency (+22 points, p=0.013) and a notable trend towards angina stability (+25 points, p=0.093) at a mean follow-up time of 222 days.

Conclusions

Myocardial ischaemia of non-obstructive origin is common in patients with chest pain and LCS. Vasomotor abnormalities related to endothelial dysfunction occurred in 82% of patients, frequently associated to impaired microvascular vasodilation or high microvascular resistance. Stratified medical treatment led to significant improvement in angina stability and frequency.

Funding Acknowledgement

Type of funding sources: None.

Glycogen Synthase Kinase-3 Maleimide Inhibitors As Potential PET-Tracers for Imaging Alzheimer's Disease: 11C-Synthesis and In Vivo Proof of Concept

Herein we present the evaluation of ¹¹C-labeled-maleimides as radiotracers for positron emission tomography imaging of GSK-3 associated with Alzheimer's disease (AD). 3-Acetyl-4-(1-[¹¹C]-methyl-1H-indol-3-yl)[1H]pyrrole-2,5-dione ([¹¹C]-2) was obtained by direct methylation using [¹¹C]-CH₃I and Cs₂CO₃ in DMF with a 31 ± 4% radiochemical yield and a radiochemical purity of 97.7 ± 0.8%. [¹¹C]-2 was stable both in its final formulation and in human plasma for 120 min and had a plasma protein binding of 70 ± 1% and a LogD_7.4 value of 1.84 ± 0.04. [¹¹C]-2 ex vivo biodistributions in healthy animals demonstrated significant brain uptake and retention, showing its ability to penetrate the intact blood-brain barrier. In vivo PET imaging in mice bearing AD showed, with respect to normal animals, significant differences in uptake in the hypothalamus, the striatum, and the amygdala and a significant increase in amygdala uptake in later stages of the pathology. These results are very promising, and further studies are being performed for a complete validation of this compound as novel tracer for AD.

Assessment of Fall-Related Emergency Medical Service Calls and Transports after a Community-Level Fall-Prevention Initiative

Background: Getting effective fall prevention into the homes of medically and physically vulnerable individuals is a critical public health challenge. Community paramedicine is emerging globally as a new model of care that allows emergency medical service units to evaluate and treat patients in non-emergency contexts for prevention efforts and chronic care management. The promise of community paramedicine as a delivery system for fall prevention that scales to community-level improvements in outcomes is compelling but untested.Objective: To study the impact of a community paramedic program's optimization of a fall prevention system entailing a clinical pathway and learning health system (called Community-FIT) on community-level fall-related emergency medical service utilization rates.Methods: We used an implementation science framework and quality improvement methods to design and optimize a fall prevention model of care that can be embedded within community paramedic operations. The model was implemented and optimized in an emergency medical service agency servicing a Midwestern city in the United States (∼35,000 residents). Primary outcome measures included relative risk reduction in the number of community-level fall-related 9-1-1 calls and fall-related hospital transports. Interrupted time series analysis was used to evaluate relative risk reduction from a 12-month baseline period (September 2016 - August 2017) to a 12-month post-implementation period (September 2018-August 2019).Results: Community paramedic home visits increased from 25 in 2017, to 236 in 2018, to 517 in 2019, indicating a large increase in the number of households that benefited from the efforts. A relative risk reduction of 0.66 (95% [CI] 0.53, 0.76) in the number of fall calls and 0.63 (95% [CI] 0.46, 0.75) in the number of fall-related calls resulting in transports to the hospital were observed.Conclusions: Community-FIT may offer a powerful mechanism for community paramedics to reduce fall-related 9-1-1 calls and transports to hospitals that can be implemented in emergency medical agencies across the country.

Penile granulomas after BCG instillations. A case report and review of literature

Penile granulomas has been rarely reported in the setting of BCG instillations. We present a 70 year-old male with multiple penile granulomas during BCG instillations due a high-grade urothelial bladder cancer. Histopathological study revealed granulomatous structures with central necrosis as seen after BCG therapy. Local treatment with cryotherapy has been shown to be effective. This case emphasizes the importance to suspect this adverse effect in patients under BCG treatment.

The Double Burden of COVID-19 and Dengue in Nepal: The challenges ahead

Coronavirus disease 2019 (COVID-19) pandemic has caused significant impact on the health care system. As a consequence, diagnosis and treatment of vector borne diseases including dengue has been equally affected. Nepal is no exception to this, where COVID-19 cases is exponentially increased and all resources are concentrated on its prevention, control and management. Dengue, one of the major vector-borne diseases in Nepal, is apparently overlooked despite approaching the peak season of the disease. The aim of this paper is to describe the double burden of COVID-19 and dengue in Nepal, particularly highlighting the co-circulation and possible coinfections. This has posed higher risk of increased severity, more severe cases and deaths in Nepal. Moreover, potential misdiagnosis of these viral diseases may lead to delayed or, inappropriate treatment and poor allocation of resources.

Variance formulae for multiphase stepped wedge cluster randomized trial

In a multiphase stepped wedge cluster randomized trial (MSW-CRT), more than one intervention will be initiated on each sequence in a fixed order. Hence, with the MSW-CRT design, the effect of the first intervention can be evaluated when compared to control, as well as the added-on effects of the subsequent interventions. Studies that use MSW-CRT have been proposed, but properties of this design have not been explicitly studied. We derive closed-form variance formulae to test the interventions' effects, which can be readily used for sample size and power calculation. Additionally, we provide relationships between variances to test the interventions' effects and design parameters. Under special conditions, some important properties include: (i) the variances to test different interventions' effects (ie, the first intervention effect and the second intervention effect) may be same; (ii) as the cluster-period mean autocorrelation increases, the variance to test an intervention effect may first increase and then decrease; (iii) as the amount of periods between the initiations of two interventions (ie, lag) increases, the variance to test an intervention effect may remain unchanged. We illustrate the relationships between power and design parameters using the variance formulae. From a few illustrative examples, we observe that the statistical test that uses data only relevant to a specific intervention has inferior power (relative power loss <15%) compared to the test when using all the study data. Also, power is reduced when both the total number of periods and lag are decreased simultaneously (relative power loss <20%).

The HEALing (Helping to End Addiction Long-term SM) Communities Study: Protocol for a cluster randomized trial at the community level to reduce opioid overdose deaths through implementation of an integrated set of evidence-based practices

BACKGROUND

Opioid overdose deaths remain high in the U.S. Despite having effective interventions to prevent overdose deaths, there are numerous barriers that impede their adoption. The primary aim of the HEALing Communities Study (HCS) is to determine the impact of an intervention consisting of community-engaged, data-driven selection, and implementation of an integrated set of evidence-based practices (EBPs) on reducing opioid overdose deaths.

METHODS

The HCS is a four year multi-site, parallel-group, cluster randomized wait-list controlled trial. Communities (n = 67) in Kentucky, Massachusetts, New York and Ohio are randomized to active intervention (Wave 1), which starts the intervention in Year 1 or the wait-list control (Wave 2), which starts the intervention in Year 3. The HCS will test a conceptually driven framework to assist communities in selecting and adopting EBPs with three components: 1) a community engagement strategy with local coalitions to guide and implement the intervention; 2) a compendium of EBPs coupled with technical assistance; and 3) a series of communication campaigns to increase awareness and demand for EBPs and reduce stigma. An implementation science framework guides the intervention and allows for examination of the multilevel contexts that promote or impede adoption and expansion of EBPs. The primary outcome, number of opioid overdose deaths, will be compared between Wave 1 and Wave 2 communities during Year 2 of the intervention for Wave 1. Numerous secondary outcomes will be examined.

DISCUSSION

The HCS is the largest community-based implementation study in the field of addiction with an ambitious goal of significantly reducing fatal opioid overdoses.

Toward indicators of the performance of US Infrastructures under climate change risks

Built infrastructures are increasingly disrupted by climate-related extreme events. Being able to monitor what climate change implies for US infrastructures is of considerable importance to all levels of decision-makers. A capacity to develop cross-cutting, widely applicable indicators for more than a dozen different kinds of infrastructure, however, is severely limited at present. The development of such indicators must be considered an ongoing activity that will require expansion and refinement. A number of recent consensus reports suggest four priorities for indicators that portray the impacts of climate change, climate-related extreme events, and other driving forces on infrastructure. These are changes in the reliability of infrastructure services and the implications for costs; changes in the resilience of infrastructures to climate and other stresses; impacts due to the interdependencies of infrastructures; and ongoing adaptation in infrastructures.

Power analysis for RNA-Seq differential expression studies using generalized linear mixed effects models

Background

Power analysis becomes an inevitable step in experimental design of current biomedical research. Complex designs allowing diverse correlation structures are commonly used in RNA-Seq experiments. However, the field currently lacks statistical methods to calculate sample size and estimate power for RNA-Seq differential expression studies using such designs. To fill the gap, simulation based methods have a great advantage by providing numerical solutions, since theoretical distributions of test statistics are typically unavailable for such designs.

Results

In this paper, we propose a novel simulation based procedure for power estimation of differential expression with the employment of generalized linear mixed effects models for correlated expression data. We also propose a new procedure for power estimation of differential expression with the use of a bivariate negative binomial distribution for paired designs. We compare the performance of both the likelihood ratio test and Wald test under a variety of simulation scenarios with the proposed procedures. The simulated distribution was used to estimate the null distribution of test statistics in order to achieve the desired false positive control and was compared to the asymptotic Chi-square distribution. In addition, we applied the procedure for paired designs to the TCGA breast cancer data set.

Conclusions

In summary, we provide a framework for power estimation of RNA-Seq differential expression under complex experimental designs. Simulation results demonstrate that both the proposed procedures properly control the false positive rate at the nominal level.

A pan-cancer study of class-3 semaphorins as therapeutic targets in cancer

BACKGROUND

Initially characterized as axon guidance factors, semaphorins also have been implicated to have critical roles in multiple physiological and developmental functions, including the regulation of immune responses, angiogenesis, organ formation, and the etiology of multiple forms of cancer. Moreover, their contribution in immunity and the regulation of tumour microenvironment is becoming increasingly recognized. Here, we provide a comprehensive analysis of class-3 semaphorins, the only secreted family of genes among veterbrate semaphorins, in terms of their expression profiles and their association with patient survival. We also relate their role with immune subtypes, tumour microenvironment, and drug sensitivity using a pan-cancer study.

RESULTS

Expression profiles of class-3 semaphorins (SEMA3s) and their association with patient survival and tumour microenvironment were studied in 31 cancer types using the TCGA pan-cancer data. The expression of SEMA3 family varies in different cancer types with striking inter- and intra- cancer heterogeneity. In general, our results show that SEMA3A, SEMA3C, and SEMA3F are primarily upregulated in cancer cells, while the rest of SEMA3s are mainly down-regulated in the tested tumours. The expression of SEMA3 family members was frequently associated with patient overall survival. However, the direction of the association varied with regards to the particular SEMA3 isoform queried and the specific cancer type tested. More specifically, SEMA3A and SEMA3E primarily associate with a poor prognosis of survival, while SEMA3G typically associates with survival advantage. The rest of SEMA3s show either survival advantage or disadvantage dependent on cancer type. In addition, all SEMA3 genes show significant association with immune infiltrate subtypes, and they also correlate with level of stromal cell infiltration and tumour cell stemness with various degrees. Finally, our study revealed that SEMA3 genes, especially SEMA3C and SEMA3F may contribute to drug induced cancer cell resistance.

CONCLUSIONS

Our systematic analysis of class-3 semaphorin gene expression and their association with immune infiltrates, tumour microenvironment and cancer patient outcomes highlights the need to study each SEMA3 member as a separate entity within each specific cancer type. Also our study validated the identification of class-3 semaphorin signals as promising therapeutic targets in cancer although further laboratory validation still needed.

Antipsychotics and women: Yes, prolactin is important

Introduction

The hormonal imbalance produced by antipsychotics can be detected by symptoms, such as: infertility, acne, hirsutism, sexual dysfunction and galactorrhea. We consider especially important the study of women's diseases, which may develop due to hyperprolactinemia, specifically: breast cancer, endometrial cancer and osteoporosis.

Objective

To undertake a systematic review about the relationship between hyperprolactinemia as a result of the treatment with antipsychoticsand endometrial and breast cancer.

Method

An exhaustive search was performed on PUBMED and COCHRANE (from 2006 to 2015).

Fifteen papers were selected including comparative studies, clinical trials and clinical reviews.

Results

With respect to endometrial carcinoma, there is no direct relationship with the use of antipsychotics. However, most papers have suggested that the blood prolactin elevation is a risk factor in the development of endometrial engrossment, which could lead to endometrial hyperplasia, polyps and endometrial cancer. Related to the use of antipsychotics as a treatment for schizophrenic women and breast carcinoma, a significant association was found and this association is strengthened through the interaction of other factors like the fact that women with schizophrenia are less worried about going to the clinical screening reviews in their health centre, smoking, and lower physical activity than healthy women.

Conclusions

Aripiprazolis associated with a low prevalence of hyperprolactinemia. Menopausal women, the obese, and women who smoke receiving antipsychotics that produce hyperprolactinemia have the greatest risk of developing endometrial pathology. Schizophrenic women with hyperprolactinemia due to antipsychotics and loss of motivation to go to screening activities have a greater risk of breast cancer. Sexual dysfunction could be a non-adherence treatment factor.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Glioblastoma infiltration of both tumor- and virus-antigen specific cytotoxic T cells correlates with experimental virotherapy responses

The mode of action for oncolytic viruses (OVs) in cancer treatment is thought to depend on a direct initial cytotoxic effect against infected tumor cells and subsequent activation of immune cell responses directed against the neoplasm. To study both of these effects in a mouse model of glioblastoma (GBM), we employed murine GBM cells engineered to constitutively express the type I Herpes Simplex Virus (HSV1) HSV-1 receptor, nectin-1, to allow for more efficient infection and replication by oncolytic HSV (oHSV). These cells were further engineered with a surrogate tumor antigen to facilitate assays of T cell activity. We utilized MRI-based volumetrics to measure GBM responses after injection with the oHSV and bioluminescent imaging (BLI) to determine oHSV replicative kinetics in the injected tumor mass. We found increased infiltration of both surrogate tumor antigen- and oHSV antigen-specific CD8+ T cells within 7 days after oHSV injection. There was no increase in tumor infiltrating CD8+ T cells expressing “exhaustion” markers, yet oHSV infection led to a reduction in PD-1+ CD8+ T cells in injected GBMs and an increase in IFNγ+ CD8+ T cells. There was a significant direct correlation between oHSV-mediated reduction in GBM volume and increased infiltration of both viral and tumor antigen-specific CD8+ T cells, as well as oHSV intratumoral gene activity. These findings imply that CD8+ T cell cytotoxicity against both tumor and viral antigens as well as intratumoral oHSV gene expression are important in oHSV-mediated GBM therapy.

Fully moderated t-statistic in linear modeling of mixed effects for differential expression analysis

BACKGROUND

Gene expression profiling experiments with few replicates lead to great variability in the estimates of gene variances. Toward this end, several moderated t-test methods have been developed to reduce this variability and to increase power for testing differential expression. Most of these moderated methods are based on linear models with fixed effects where residual variances are smoothed under a hierarchical Bayes framework. However, they are inadequate for designs with complex correlation structures, therefore application of moderated methods to linear models with mixed effects are needed for differential expression analysis.

RESULTS

We demonstrated the implementation of the fully moderated t-statistic method for linear models with mixed effects, where both residual variances and variance estimates of random effects are smoothed under a hierarchical Bayes framework. We compared the proposed method with two current moderated methods and show that the proposed method can control the expected number of false positives at the nominal level, while the two current moderated methods fail.

CONCLUSIONS

We proposed an approach for testing differential expression under complex correlation structures while providing variance shrinkage. The proposed method is able to improve power by moderation and controls the expected number of false positives properly at the nominal level.

Identification of a Subtype of Hepatocellular Carcinoma with Poor Prognosis Based on Expression of Genes within the Glucose Metabolic Pathway

Hepatocellular carcinoma (HCC) is the most prevalent primary cancer and a highly aggressive liver malignancy. Liver cancer cells reprogram their metabolism to meet their needs for rapid proliferation and tumor growth. In the present study, we investigated the alterations in the expression of the genes involved in glucose metabolic pathways as well as their association with the clinical stage and survival of HCC patients. We found that the expressions of around 30% of genes involved in the glucose metabolic pathway are consistently dysregulated with a predominant down-regulation in HCC tumors. Moreover, the differentially expressed genes are associated with an advanced clinical stage and a poor prognosis. More importantly, unsupervised clustering analysis with the differentially expressed genes that were also associated with overall survival (OS) revealed a subgroup of patients with a worse prognosis including reduced OS, disease specific survival, and recurrence-free survival. This aggressive subtype had significantly increased expression of stemness-related genes and down-regulated metabolic genes, as well as increased immune infiltrates that contribute to a poor prognosis. Collectively, this integrative study indicates that expressions of the glucose metabolic genes could be used as potential prognostic markers and/or therapeutic targets, which might be helpful in developing precise treatment for patients with HCC.

P6391Major acute cardiovascular events in patients with inflammatory bowel disease

Introduction

Traditional risk factors for coronary heart disease have been reported in around 85% patients who present with myocardial infarction. More recently, inflammation and immune mediated diseases have been associated with ischemic heart disease.

Inflammatory Bowel Disease (IBD) is an immune mediated disorder which comprises of ulcerative colitis and Crohn's disease. Estimated prevalence of IBD in the United States in 2004 was 1.4 million people. These patients have an overall increased risk of thrombotic complications with microvascular thrombosis hypothesized to contribute in disease pathogenesis.

Results from a recent meta-analysis were consistent with increased risk of ischemic heart disease among IBD patients, with risk greater in females and younger patients, although heterogeneity was considerable in overall data. Also, in a recent study, IBD was found to be associated with an increased risk of acute myocardial infarction and heart failure despite lower prevalence of coronary risk factors in IBD patients.

IBD pathogenesis involves sustained activation of immune responses with upregulation of cytokines including but not limited to IL-1 beta, IL-6 and TNF-alpha. Upregulation of these cytokines has also been reported in coronary atherosclerosis.

Based on above information, we explored incidence of MACE (Major Adverse Cardiac Event) in this patient population from our health system data-base.

Methods

Propensity scores were estimated for all 15,292 (0.4%) patients with inflammatory bowel disease from a total patient pool of 3,917,894 patients in our health system to assemble a 1:1 matched cohort balanced for age, gender, race and known cardiovascular risk factors including hypertension, hyperlipidemia, diabetes mellitus and smoking (current and former). ICD-9 and ICD-10 codes were used to identify cardiovascular risk factors and outcomes.

Results

Matched patients (n=30,584) had a mean age of 51 years, with 58% of all being women, and 63% Caucasian. During the median follow up of 4.4 years all-cause mortality was observed in 1.7% and 1.2% of patients from IBD and non-IBD groups respectively (hazard ratio {HR}, 1.31; 95% confidence interval {CI}, 1.08–1.58; p=0.005). Combined outcome for myocardial infarction or all-cause mortality was noted in 4.1% and 3.4% from IBD and non-IBD groups respectively (HR, 1.16; 95% CI, 1.03–1.30; p=0.014) while HRs for cardiovascular mortality, myocardial infarction and unstable angina independently were 1.04 (0.74–1.47; p=0.833), 1.05 (0.89–1.23; p=0.591) and 1.10 (0.83–1.46; p=0.524) respectively.

Conclusion

Inflammatory bowel disease did not show association with myocardial infarction, cardiovascular mortality or unstable angina when matched for known cardiovascular risk factors, but was associated with increased all-cause mortality and combined end-point of all-cause mortality or myocardial infarction.

P1551A genetic risk score predicts recurrent events after myocardial infarction in young adults

Background

To evaluate whether a genetic risk score (GRS) improves the prediction of recurrent events in young non-diabetic patients presenting with an acute myocardial infarction and identifies a more aggressive form of atherosclerosis in this population.

Methods and results

We performed a prospective study including 81 consecutive non-diabetic patients aged below 55 y.o. presenting with an acute myocardial infarction (48±6 y.o., 89% male). A comprehensive study including serum biomarkers, genetic testing and cardiac CT was performed. We studied the association of a GRS composed of 11 genetic variants with a primary composite end-point (all-cause mortality, recurrent acute coronary syndrome, and cardiac re-hospitalisation). After a median follow-up of 4.1 (3.5 - 4.4) years 24 recurrent events were documented. A significantly higher prevalence of 9 out of 11 risk alleles was noted compared with general population. The GRS was significantly associated with recurrent events, especially when baseline LDL-cholesterol levels were elevated. Compared with the low-risk GRS category, the multivariate-adjusted hazard ratio for recurrent events for the intermediate-risk GRS category was 10.2 (95% CI 1.1–100.3, p=0.04) and for the high-risk GRS was 20.7 (2.4–181.0, p=0.006) when LDL-C ≥2.8 mmol/L. Inclusion of the GRS improved the C statistic (ΔC statistic =0.086), the continuous Net Reclassification Index (30%) and the Integrated Discrimination Improvement (0.05) compared with a multivariate clinical risk model. Cardiac CT detected coronary calcified atherosclerosis and numerous plaques but it had a limited value for prediction of recurrences. No association was observed between extracellular matrix metabolism biomarkers and GRS or recurrent events in this population.

Cox regression analysis between GRS terciles and LDL-C Univariate analysis Multivariate analysis* HR (95% CI) p-value HR (95% CI) p-value* Low GRS 1 1 Intermediate GRS 2.0 (0.7–5.8) 0.21 LDL-C≤110 mg/dL (≤2.8 mmol/L) 1.0 (0.3–4.0) >110 mg/dL (>2.8 mmol/L) 10.2 (1.1–100.3) 0.04 High GRS 3.0 (1.0–9.2) 0.05 LDL-C≤110 mg/dL (≤2.8 mmol/L) 0.3 (0.1–1.9) >110 mg/dL (>2.8 mmol/L) 20.7 (2.4–181.0) 0.006 *Multivariate model adjusted for GRACE risk score and LDL-C and interaction. There was a strong interaction between GRS terciles and LDL-C (p<0.01).

Recurrent events based on genetic risk

Conclusions

A multilocus genetic risk score identified non-diabetic young patients at increased risk for recurrent events after a myocardial infarction. The significance of LDL-cholesterol in relation to genetic predisposition for recurrences merits further evaluation.

Acknowledgement/Funding

Instituto de Salud Carlos III (PI12/0564, PI14/01152 and PI15/00667), the CIBERCV and the Spanish Society of Cardiology (2015/CC)

A new clinical score to identify children at low risk for appendicitis

BACKGROUND

Besides clinical signs and imaging, in recent years, biomarkers have proven to be a viable diagnostic resource for acute appendicitis (AA).

OBJECTIVE

The objective of this study was to develop a clinical score including clinical signs and a combination of biomarkers to identify children with abdominal pain at low risk of AA.

DESIGN/METHODS

We prospectively included children 2 to 14 years of age with abdominal pain suggestive of AA who presented to the emergency department between July 2016 and September 2017. A new score, the Pediatric Appendicitis Laboratory Score (PALabS) including clinical signs, leucocyte (WBC) and neutrophil (ANC) counts and plasma C-reactive protein (CRP) and calprotectin (CP) levels was developed and validated through secondary analyses of two distinct cohorts The validation sample included visits to a single pediatric emergency department from 2012 to 2013 and 2016 to 2017.

RESULTS

The derivation sample included 278 children, 35.9% of whom had AA and the validation sample included 255 children, 49% of whom had AA. Using logistic regression, we created a 6-part score that consisted of nausea (3 points), history of focal right lower quadrant pain (4 points), ANC of ≥7500/μL (7 points), WBC of ≥10,000/μL (4 points), CRP ≥ 10.0 mg/L (2 points) and CP ≥ 0.50 ≥ ng/mL (3 points). This score exhibited a high discriminatory power (area under the curve: 0.88; 95% confidence interval: 0.84 to 0.92) and outperformed the PAS and Kharbanda scores (area under the curve: 0.76; 95% confidence interval: 0.71 to 0.82 and 0.82; 95% confidence interval: 0.77 to 0.87, respectively). A PALabS ≤6 had a sensitivity of 99.2% (95% confidence interval [CI]: 95.6-99.9), negative predictive value of 97.6% (95% CI: 87.7-99.6), and negative likelihood ratio of 0.03 (95% CI: 0.00-0.18) in the validation set.

CONCLUSION

In our validation cohort of patients with acute abdominal pain, the new score can accurately predict which children are at low risk of appendicitis and could be safely managed with close observation.

Abstract P2-08-58: Prognostic factors of survival in node positive breast cancer patients after neoadjuvant chemotherapy in a large series after 5y follow-up: Can response overcome the poor prognosis of nodal stage?

Background: Status of the axilla is one of the most significant prognostic factors in breast cancer (BC) patients. On the other hand, response to neoadjuvant chemotherapy (NACT) is related to survival. The aim of the present study is to analyze which prognostic factors impact most on Node positive (N+) BC patient survival after NATC. Material and methods: Retrospective analyses on a series of N+ BC patients treated with NATC based on anthracyclines and taxanes +/- trastuzumab if HER2 positive tumors, between June 2008 and December 2016. Clinical, radiological and pathological outcomes have been evaluated. Residual cancer burden (RCB) 1 and the neoadjuvant response index (INR) 2 have been recorded. Survival was calculated with Kaplan-Meier survival curve since the start of NATC to the first documented disease recurrence (DFS) or death (OS). Hazard ratios (HRs) with 95% CIs were estimated with cox proportional hazards regression analysis and subgroups were compared with a two-sided log-rank test. Results: A total of 345 N+ BC patients were included. Pathological complete response was achieved in 72 (20.8%) patients. After NACT, 137 (39.6%) become ypN0, 9 (2.6%) ypN1 mic, 113 (32.7%) ypN1, 60 (17.3%) ypN2 and 26 (7.6%) N3. Those independent predictive factor of ypN0 were molecular subtype (TN and Her2+) with OR: 7.7, p&lt;0.001 and clinical response with OR 6.88, p: 0.04. At a mean follow-up of 58 months there have been 73 (21.1%) recurrences: 9 (2.3%) local, 45 (13%) systemic, 15 (4.3%) systemic+ local, 3 (0.9%) axilla, 1 (0.3%) supraclavicular. The estimated 5y OS was 87.8%. The univariate analysis according to DSF is detailed in Table1.

Adjusted univariate anaalysis cox regression of clinical and pathological factors of desease free survivalBMI10.989-1.010.963AGE0.9960.953-1.0420.876Dose NATC0.9940.979-1.0080.402Clinical Stage1.4021.077-1.8260.012Rx Image1.260.803-1.9940.311Rx size1.0090.995-1.0240.217Number suspicious ALN1.0950.801-1.4970.57Molecular subtype TN,HER20.8800.534-1.450.616Nottinghan grade1.0460.753-1.4530.789Histological subtype1.4651.044-2.0570.27MOlecular subtype1.1510.956-1.3850.137Vascular invasion1.6761.137-24710.009Clinical response2.3691.709-3.284&lt;0.001Fibrosis tumor bed0.980.972-0.989&lt;0.001Nodal fibrosis&gt;50%1.7950.874-3.6860.111Pathological tumoral response1.6861.175-2.4180.005ypN03.561.853-6.838&lt;0.001NRI0.330.192-0.565&lt;0.001RCB1.2741.106-1.4680.001

In the multivariate model those parameters that were independently prognostic were clinical response HR: 5.44 (IC95% 2.275-13.042, p&lt;0.001) and clinical stage HR: 2.364 (IC95% 1.018-5.490, p: 0.045). Conclusions: The most significant prognostic factor in our N+ series was response to NATC, followed by clinical stage. Those independently predictive factors of axillar response (ypN0) were molecular subtype (TN and Her2+) and clinical response. In conclusion, in those patients with chemo sensitive tumors, lymphadenectomy could be safely spared with a more selective axillary approach.

Citation Format: Fernandez S, Garcia A, Vethencourt A, Vazquez S, Petit A, Pla MJ, Ortega R, Pérez J, Gil M, Ponce J, Pernas S, Lopez A, Falo C. Prognostic factors of survival in node positive breast cancer patients after neoadjuvant chemotherapy in a large series after 5y follow-up: Can response overcome the poor prognosis of nodal stage? [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 P2-08-58.

Pharmacokinetic-Pharmacodynamic Model of Neutropenia in Patients With Myeloma Receiving High-Dose Melphalan for Autologous Stem Cell Transplant

High-dose melphalan (HDM) is part of the conditioning regimen in patients with multiple myeloma (MM) receiving autologous stem cell transplantation (ASCT). However, individual sensitivity to melphalan varies, and many patients experience severe toxicities. Prolonged severe neutropenia is one of the most severe toxicities and contributes to potentially life-threatening infections and failure of ASCT. Granulocyte-colony stimulating factor (G-CSF) is given to stimulate neutrophil proliferation after melphalan administration. The aim of this study was to develop a population pharmacokinetic/pharmacodynamic (PK/PD) model capable of predicting neutrophil kinetics in individual patients with MM undergoing ASCT with high-dose melphalan and G-CSF administration. The extended PK/PD model incorporated several covariates, including G-CSF regimen, stem cell dose, hematocrit, sex, creatinine clearance, p53 fold change, and race. The resulting model explained portions of interindividual variability in melphalan exposure, therapeutic effect, and feedback regulation of G-CSF on neutrophils, thus enabling simulation of various doses and prediction of neutropenia duration.

Arming an Oncolytic Herpes Simplex Virus Type 1 with a Single-chain Fragment Variable Antibody against PD-1 for Experimental Glioblastoma Therapy

PURPOSE

Glioblastoma (GBM) is resistant to standard of care. Immune checkpoints inhibitors (such as anti-PD-1 mAbs) efficiently restore antitumor T-cell activity. We engineered a new oncolytic herpes simplex virus (oHSV) expressing a single-chain antibody against PD-1 (scFvPD-1) to evaluate its efficacy in mouse models of GBM.

EXPERIMENTAL DESIGN

NG34scFvPD-1 expresses the human GADD34 gene transcriptionally controlled by the Nestin promoter to allow replication in GBM cells and a scFvPD-1 cDNA transcriptionally controlled by the CMV promoter. ELISA assays were performed to detect binding of scFvPD-1 to mouse and human PD-1. In vitro cytotoxicity and replication assays were performed to measure NG34scFvPD-1 oncolysis, and scFvPD-1 expression and secretion were determined. In vivo survival studies using orthotopic mouse GBM models were performed to evaluate the therapeutic potency of NG34scFvPD-1.

RESULTS

NG34scFvPD-1-infected GBM cells express and secrete scFvPD-1 that binds mouse PD-1. The introduction of the scFvPD-1 sequence in the viral backbone does not alter the oncolytic properties of NG34scFvPD-1. In situ NG34scFvPD-1 treatment improved the survival with a tail of durable survivorship in 2 syngeneic immunocompetent mouse models of GBM. Mice that survived the first GBM challenge rejected the second challenge of GBM when implanted in the contralateral hemisphere. However, this was not true when athymic mice were employed as the recipients of the second challenge, consistent with the need for an intact immune system to obtain a memory response.

CONCLUSIONS

NG34scFvPD-1 treatment induces a durable antitumor response in 2 preclinical mouse models of GBM with evidence for antitumor memory.

Persistent major alopecia following adjuvant docetaxel for breast cancer: incidence, characteristics, and prevention with scalp cooling

Background

Persistent alopecia (PA) after docetaxel has been recently described. The aim of our study is to establish the incidence and characteristics of PA following adjuvant docetaxel for breast cancer (BC) and to test the ability of scalp cooling in prevention.

Patients and methods

BC patients receiving adjuvant chemotherapy followed or not by endocrine therapy (and a control group receiving only endocrine therapy) were interviewed in a single institution at 1.5 to 5 years following primary diagnosis searching for PA. A confirmatory prevalence study was later performed in other two institutions. Finally, a prevention study using prophylactic scalp cooling (PSC) with ELASTO-GEL hypothermia caps in patients receiving adjuvant docetaxel was performed.

Results

In the initial prevalence study (492 patients), minor forms of PA (grade 1) were recorded with all chemotherapy regimens and aromatase inhibitors. Patients receiving docetaxel regimens at cumulative dose (CD) ≥ 400 mmg/m² presented a significantly higher prevalence of grades 1 PA (33–52%) and 2 PA (5–12%). Prevalence of grade 2 PA with docetaxel CD ≥ 400 mmg/m² was confirmed in two other institutions. Overall, grade 2 PA was seen in 10.06% (95% CI 7.36–13.61) of 358 patients with docetaxel regimens reaching CD ≥ 400 mmg/m², but not in patients with lower docetaxel CD, other chemotherapy regimens, or endocrine therapy alone. In prevention trial, no grade 2 PA occurred among 116 patients receiving adjuvant docetaxel (≥ 400 mmg/m²) and PSC followed-up after a 96 months median time. PSC was well tolerated. No scalp relapses were seen among 30 patients (22% of all inclusions) having disease relapse.

Conclusion

Adjuvant treatment with docetaxel (CD ≥ 400 mmg/m²) is associated with a significant rate of grade 2 PA, leading to wearing a wig, in around 10% of patients. This toxicity was completely prevented with scalp cooling. Clinical Trial Reference: NCT00515762.

Electronic supplementary material

The online version of this article (10.1007/s10549-018-4855-2) contains supplementary material, which is available to authorized users.

Ultraviolet radiation in the Atacama Desert

The world's highest levels of surface ultraviolet (UV) irradiance have been measured in the Atacama Desert. This area is characterized by its high altitude, prevalent cloudless conditions, and a relatively low total ozone column. In this paper, we provide estimates of the surface UV (monthly UV index at noon and annual doses of UV-B and UV-A) for all sky conditions in the Atacama Desert. We found that the UV index at noon during the austral summer is expected to be greater than 11 in the whole desert. The annual UV-B (UV-A) doses were found to range from about 3.5 kWh/m² (130 kWh/m²) in coastal areas to 5 kWh/m² (160 kWh/m²) on the Andean plateau. Our results confirm significant interhemispherical differences. Typical annual UV-B doses in the Atacama Desert are about 40% greater than typical annual UV-B doses in northern Africa. Mostly due to seasonal changes in the ozone, the differences between the Atacama Desert and northern Africa are expected to be about 60% in the case of peak UV-B levels (i.e. the UV-B irradiances at noon close to the summer solstice in each hemisphere). Interhemispherical differences in the UV-A are significantly lower since the effect of the ozone in this part of the spectrum is minor.

Blackwater fever in a non-immune patient with Plasmodium falciparum malaria after intravenous artesunate

Blackwater fever was typically reported after quinine administration, although it is poor recognized in patients receiving artesunate. This case describes a blackwater fever in a non-immune patient after artesunate for severe malaria. It highlights the importance of monitoring haemolytic parameters in severe malaria to avoid renal impairment or severe anaemia.