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Abstract With the approval of new therapies targeting the PI3K pathway, the detection of PIK3CA mutations has become a key factor in treatment management for HR+/HER2− metastatic breast cancer (MBC). We developed multiplex digital PCR (dPCR) assays to detect and quantify PIK3CA mutations. A first screening assay allows the detection of 21 mutations, with a drop-off system targeting the 542–546 hotspot mutations combined with the simultaneous detection of N345K, C420R, H1047L and H1047R mutations. In the case of a positive result, a sequential strategy based on other assays that we have developped allows for precise mutation identification. Clinical validity was determined by analyzing plasma circulating free DNA (cfDNA) from 213 HR+/HER2− MBC samples, as well as DNA extracted from 97 available matched tumors from 89 patients. Our assays have shown reliable specificity, accuracy and reproducibility, with limits of blank of three and four droplets for the screening assay. Sixty-eight patients (32%) had at least one PIK3CA mutation detectable in their plasma, and we obtained 83.1% agreement between the cfDNA analysis and the corresponding tumors. The high sensitivity and robustness of these new dPCR assays make them well-suited for rapid and cost-effective detection of PIK3CA mutations in the plasma of MBC patients.

Abstract Cerebral microhemorrhages (CMHs) are associated with cerebrovascular disease, cognitive impairment, and normal aging. One method to study CMHs is to analyze histological sections (5–40 μm) stained with Prussian blue. Currently, users manually and subjectively identify and quantify Prussian blue-stained regions of interest, which is prone to inter-individual variability and can lead to significant delays in data analysis. To improve this labor-intensive process, we developed and compared three digital pathology approaches to identify and quantify CMHs from Prussian blue-stained brain sections: (1) ratiometric analysis of RGB pixel values, (2) phasor analysis of RGB images, and (3) deep learning using a mask region-based convolutional neural network. We applied these approaches to a preclinical mouse model of inflammation-induced CMHs. One-hundred CMHs were imaged using a 20 × objective and RGB color camera. To determine the ground truth, four users independently annotated Prussian blue-labeled CMHs. The deep learning and ratiometric approaches performed better than the phasor analysis approach compared to the ground truth. The deep learning approach had the most precision of the three methods. The ratiometric approach has the most versatility and maintained accuracy, albeit with less precision. Our data suggest that implementing these methods to analyze CMH images can drastically increase the processing speed while maintaining precision and accuracy.

Quantifying rapidly varying perturbations in cerebral tissue absorption and scattering can potentially help to characterize changes in brain function caused by ischemic trauma. We have developed a platform for rapid intrinsic signal brain optical imaging using macroscopically structured light. The device performs fast, multispectral, spatial frequency domain imaging (SFDI), detecting backscattered light from three-phase binary square-wave projected patterns, which have a much higher refresh rate than sinusoidal patterns used in conventional SFDI. Although not as fast as "single-snapshot" spatial frequency methods that do not require three-phase projection, square-wave patterns allow accurate image demodulation in applications such as small animal imaging where the limited field of view does not allow single-phase demodulation. By using 655, 730, and 850 nm light-emitting diodes, two spatial frequencies ([Formula: see text] and [Formula: see text]), three spatial phases (120 deg, 240 deg, and 360 deg), and an overall camera acquisition rate of 167 Hz, we map changes in tissue absorption and reduced scattering parameters ([Formula: see text] and [Formula: see text]) and oxy- and deoxyhemoglobin concentration at [Formula: see text]. We apply this method to a rat model of cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) to quantify hemodynamics and scattering on temporal scales ([Formula: see text]) ranging from tens of milliseconds to minutes. We observe rapid concurrent spatiotemporal changes in tissue oxygenation and scattering during CA and following CPR, even when the cerebral electrical signal is absent. We conclude that square-wave SFDI provides an effective technical strategy for assessing cortical optical and physiological properties by balancing competing performance demands for fast signal acquisition, small fields of view, and quantitative information content.

Burn wounds are often characterized by injury depth, which then dictates wound management strategy. While most superficial burns and full thickness burns can be diagnosed through visual inspection, clinicians experience difficulty with accurate diagnosis of burns that fall between these extremes. Accurately diagnosing burn severity in a timely manner is critical for starting the appropriate treatment plan at the earliest time points to improve patient outcomes. To address this challenge, research groups have studied the use of commercial laser Doppler imaging (LDI) systems to provide objective characterization of burn-wound severity. Despite initial promising findings, LDI systems are not commonplace in part due to long acquisition times that can suffer from artifacts in moving patients. Commercial LDI systems are being phased out in favor of laser speckle imaging (LSI) systems that can provide similar information with faster acquisition speeds. To better understand the accuracy and usefulness of commercial LSI systems in burn-oriented research, we studied the performance of a commercial LSI system in three different sample systems and compared its results to a research-grade LSI system in the same environments. The first sample system involved laboratory measurements of intralipid (1%) flowing through a tissue simulating phantom, the second preclinical measurements in a controlled burn study in which wounds of graded severity were created on a Yorkshire pig, and the third clinical measurements involving a small sample of clinical patients. In addition to the commercial LSI system, a research grade LSI system that was designed and fabricated in our labs was used to quantitatively compare the performance of both systems and also to better understand the "Perfusion Unit" output of commercial systems.

In the present study, we have developed a multi-modal instrument that combines laser speckle imaging, arterial blood pressure, and electroencephalography (EEG) to quantitatively assess cerebral blood flow (CBF), mean arterial pressure (MAP), and brain electrophysiology before, during, and after asphyxial cardiac arrest (CA) and resuscitation. Using the acquired data, we quantified the time and magnitude of the CBF hyperemic peak and stabilized hypoperfusion after resuscitation. Furthermore, we assessed the correlation between CBF and MAP before and after stabilized hypoperfusion. Finally, we examined when brain electrical activity resumes after resuscitation from CA with relation to CBF and MAP, and developed an empirical predictive model to predict when brain electrical activity resumes after resuscitation from CA. Our results show that: 1) more severe CA results in longer time to stabilized cerebral hypoperfusion; 2) CBF and MAP are coupled before stabilized hypoperfusion and uncoupled after stabilized hypoperfusion; 3) EEG activity (bursting) resumes after the CBF hyperemic phase and before stabilized hypoperfusion; 4) CBF predicts when EEG activity resumes for 5-min asphyxial CA, but is a poor predictor for 7-min asphyxial CA. Together, these novel findings highlight the importance of using multi-modal approaches to investigate CA recovery to better understand physiological processes and ultimately improve neurological outcome.

Abstract Background The optimal duration of intravenous antibiotic therapy in Staphylococcus aureus prosthetic bone and joint infection has not been established. The objective of this study was to compare the effect of early and late intravenous-to-oral antibiotic switch on treatment failure. Patients and methods We retrospectively analyzed all adult cases of S. aureus prosthetic bone and joint or orthopedic metalware-associated infection between January 2008 and December 2015 in a French university hospital. The primary outcome was treatment failure defined as the recurrence of S. aureus prosthetic bone and joint or orthopedic metalware-associated infection at any time during or after the first line of medical and surgical treatment within 2 years of follow-up. A Cox model was created to assess risk factors for treatment failure. Results Among the 140 patients included, mean age was 60.4 years (SD 20.2), and 66% were male (n = 92). Most infections were due to methicillin-susceptible S. aureus (n = 113, 81%). The mean duration of intravenous antibiotic treatment was 4.1 days (SD 4.6). The majority of patients (119, 85%) had ≤5 days of intravenous therapy. Twelve patients (8.5%) experienced treatment failure. Methicillin-resistant S. aureus infections (HR 11.1; 95% CI 1.5–111.1; p = 0.02), obesity (BMI > 30 kg/m2) (HR 6.9; 95% CI1.4–34.4, p = 0.02) and non-conventional empiric antibiotic therapy (HR 7.1; 95% CI 1.8–25.2; p = 0.005) were significantly associated with treatment failure, whereas duration of intravenous antibiotic therapy (≤ 5 or > 5 days) was not. Conclusion There was a low treatment failure rate in patients with S. aureus prosthetic bone and joint or orthopedic metalware-associated infection with early oral switch from intravenous to oral antibiotic therapy.

Background: Cervical cancers are mainly caused by an oncogenic HPV. For locally advanced stages, the standard treatment is radio-chemotherapy (RTCT) followed by brachytherapy. Nevertheless, the prognosis remains highly heterogeneous between patients. Objective: We investigated the prognostic value of HPV circulating tumor DNA (ctDNA) in locally advanced cervical cancers alongside that of Squamous Cell Carcinoma Antigen (SCC-A). Methods: This single-center retrospective study included patients treated in curative intent for an IB3 to IVA squamous cell cervical cancer. Quantification of HPV ctDNA in serum collected at diagnosis was performed using a multiplex digital PCR assay for the simultaneous detection of 8 HPV genotypes. Results: Among the 97 patients included, 76 patients (78.4%) were treated by RTCT, followed by brachytherapy for 57 patients (60%). HPV ctDNA was detected in 59/97 patients at diagnosis (60.8%). This detection was associated with lymph node invasion (p=0.04) but not with tumor stage. A high level of SCC-A at diagnosis was associated with tumor stage (p=0.008) and lymph node invasion (p=0.012). In univariate analysis, better disease-free survival (DFS) was associated with optimal RTCT regimen (p=0.002), exposure to brachytherapy (p=0.0001) and a low SCC-A at diagnosis (continuous analysis, p=0.002). Exploratory analysis revealed that 3/3 patients (100%) whose HPV ctDNA was still detectable at the end of treatment relapsed, while 6/22 patients (27.3%) whose HPV ctDNA was negative at the end of treatment relapsed. Conclusion: HPV ctDNA detection at diagnosis of locally advanced cervical squamous cell carcinomas is frequent and related to node invasion, but not to DFS. The prognostic value of HPV ctDNA detection after treatment warrants specific studies. [ABSTRACT FROM AUTHOR]

Lake sediments are valuable archives and can help construct a chronology of event deposits induced by seismic events. Such a chronology can be used to better understand the recurrence times between seismic events over longer periods than those covered by historical seismicity catalogs. However, only a few studies in lake palaeoseismology have focused on areas with moderate seismicity. This study aims to improve the catalog of paleoseismological archives in the front of the Western Alps. In this part, new multi-proxy data from the sedimentary archives of Lake Aiguebelette (France) allow the identification of 32 homogenites (thickness ≥ 0.5 cm) interpreted as of coseismic origin over the Holocene. An age model based on short-lived radionuclides, paleomagnetic data and radiocarbon ages constrains the chronology of sedimentary deposits in the deep basin of Lake Aiguebelette. Among these homogenites, several were deposited at time intervals compatible with historical seismic events. To correlate the historical seismic events likely to have generated the event deposits identified in the sedimentary sequences of the deep basin of Lake Aiguebelette, the Earthquake Sensitivity Threshold Index (ESTI) method is used. Historical seismicity catalogs with uncertainties about intensities and epicenter coordinates for earthquakes make correlations to event deposits difficult. To better understand which seismic events may have been archived, a relative comparison was conducted between the pseudospectral acceleration (PSA) values calculated for each event in the FCAT-17 seismic catalog and for two distinct frequencies. Based on this PSA approach, for higher frequencies (5 Hz), the contribution of nearby and moderate events is significantly stronger than that of strong and distant events in the lake sequence of Aiguebelette. Thus, the chronicle established based on the event deposits archived in Lake Aiguebelette sediment is interpreted as representative of local events (epicentral distance to the lake < 50 km). Recurrence intervals between the deposition of event layers do not follow a specific distribution (log-normal, Weibull, gamma or exponential) but might be a combination of several distributions. This suggests possible coexistence of several processes over the Holocene, impacting the evolution of the seismicity in this area. [ABSTRACT FROM AUTHOR]

Social inequalities tended to increase in the context of the pandemic, particularly in relation to the measures taken to manage and reduce the risk of COVID-19. When lockdown measures required the general population “to stay home”, what were homeless people expected to do? The ECHO study is a cross-sectional, descriptive study with a convergent mixed-method design. Data were collected across shelters in France both during and immediately following the lockdown (April – June 2020). This article presents the study’s qualitative findings, with a focus on understanding both the experiences and perceptions among these populations of the measures taken to limit the COVID-19 infection. A total of 26 semi-directed individual interviews were conducted across seven shelters in both Lyon (42%) and Paris (58%). Data were analysed using thematic content analysis with partial blinded coding. Four key themes were identified: 1- Reactions to the introduction of lockdown: a sudden implementation reminiscent of prior violent or traumatic circumstances amongst participants, 2- Accommodation during lockdown: participants’ conflicting visions of the shelter, 3- Influence of the media and public communication: an abundant flow of information impacting participant’s wellbeing and representations on the pandemic, and 4- The individual impact of lockdown: perceived health and limitations to daily life activities. The most vulnerable populations have borne the heaviest burden during the pandemic. It is therefore crucial that we improve both the availability of information, and the health literacy of, all groups within the national population.

The incidence of cardiovascular diseases is increasing worldwide with the growing aging of the population. Biological aging has major influence on the vascular tree and is associated with critical changes in the morphology and function of the arterial wall together with an extensive remodeling of the vascular extracellular matrix. Elastic fibers fragmentation and release of elastin degradation products, also known as elastin-derived peptides (EDPs), are typical hallmarks of aged conduit arteries. Along with the direct consequences of elastin fragmentation on the mechanical properties of arteries, the release of EDPs has been shown to modulate the development and/or progression of diverse vascular and metabolic diseases including atherosclerosis, thrombosis, type 2 diabetes and nonalcoholic steatohepatitis. Most of the biological effects mediated by these bioactive peptides are due to a peculiar membrane receptor called elastin receptor complex (ERC). This heterotrimeric receptor contains a peripheral protein called elastin-binding protein, the protective protein/cathepsin A, and a transmembrane sialidase, the neuraminidase-1 (NEU1). In this review, after an introductive part on the consequences of aging on the vasculature and the release of EDPs, we describe the composition of the ERC, the signaling pathways triggered by this receptor, and the current pharmacological strategies targeting ERC activation. Finally, we present and discuss new regulatory functions that have emerged over the last few years for the ERC through desialylation of membrane glycoproteins by NEU1, and its potential implication in receptor transactivation.

The James Webb Space Telescope will revolutionize transiting exoplanetatmospheric science due to its capability for continuous, long-durationobservations and its larger collecting area, spectral coverage, and spectralresolution compared to existing space-based facilities. However, it is unclearprecisely how well JWST will perform and which of its myriad instruments andobserving modes will be best suited for transiting exoplanet studies. In thisarticle, we describe a prefatory JWST Early Release Science (ERS) program thatfocuses on testing specific observing modes to quickly give the community thedata and experience it needs to plan more efficient and successful futuretransiting exoplanet characterization programs. We propose a multi-prongedapproach wherein one aspect of the program focuses on observing transits of asingle target with all of the recommended observing modes to identify andunderstand potential systematics, compare transmission spectra at overlappingand neighboring wavelength regions, confirm throughputs, and determine overallperformances. In our search for transiting exoplanets that are well suited toachieving these goals, we identify 12 objects (dubbed "community targets") thatmeet our defined criteria. Currently, the most favorable target is WASP-62bbecause of its large predicted signal size, relatively bright host star, andlocation in JWST's continuous viewing zone. Since most of the community targetsdo not have well-characterized atmospheres, we recommend initiating preparatoryobserving programs to determine the presence of obscuring clouds/hazes withintheir atmospheres. Measurable spectroscopic features are needed to establishthe optimal resolution and wavelength regions for exoplanet characterization.Other initiatives from our proposed ERS program include testing the instrumentbrightness limits and performing phase-curve observations.(Abridged)

The authors regret omission of an acknowledgment of funding provided by National Institutes of Health grant R01 NS020989. The authors would like to apologize for any inconvenience caused.

Cerebral amyloid angiopathy (CAA) is a neurovascular disease that is strongly associated with an increase in the number and size of spontaneous microbleeds. Conventional methods of magnetic resonance imaging for detection of microbleeds, and positron emission tomography with Pittsburgh Compound B imaging for amyloid deposits, can separately demonstrate the presence of microbleeds and CAA in affected brains in vivo; however, there still is a critical need for strong evidence that shows involvement of CAA in microbleed formation. Here, we show in a Tg2576 mouse model of Alzheimers disease, that the combination of histochemical staining and an optical clearing method called optical histology, enables simultaneous, co-registered three-dimensional visualization of cerebral microvasculature, microbleeds, and amyloid deposits. Our data suggest that microbleeds are localized within the brain regions affected by vascular amyloid deposits. All observed microhemorrhages (n=39) were in close proximity (0 to 144 μm) with vessels affected by CAA. Our data suggest that the predominant type of CAA-related microbleed is associated with leaky or ruptured hemorrhagic microvasculature. The proposed methodological and instrumental approach will allow future study of the relationship between CAA and microbleeds during disease development and in response to treatment strategies.