IZCp and PZCp: Redox Non-innocent Cyclopentadienyl Ligands as Electron Reservoirs for Sandwich Complexes

A long-sustained effort of systematic steric and electronic modification of cyclopentadienyl (Cp) ligands has enabled them to find wide-ranging, valuable applications. Herein, we present two novel Cp ligands: imidazolium- and pyrrolinium-substituted zwitterionic Cps (IZCp and PZCp), whose key utility is redox non-innocence─the ability to participate cooperatively with the metal center in redox reactions. Through the simple metalation of ZCps, the Cr(0) and Mo(0) half-sandwich complexes (IZCp)Cr(CO)3, (PZCp)Cr(CO)3, (IZCp)Mo(CO)3, and (PZCp)Mo(CO)3, respectively, as well as the Ru(II) sandwich complexes [(IZCp)RuCp]PF6 and [(PZCp)RuCp]PF6 were prepared. The sandwich complexes were fully characterized and showed by cyclic voltammetry reversible one-electron reduction at E1/2 potentials ranging from -1.7 to -2.7 V vs Fc/Fc+. These values are unusually low and have not been observed with other Cp ligands due to the instability of the reduced complexes. Density functional theory (DFT) calculations for the reduced sandwich derivatives with IZCp and PZCp showed their spin densities to be highly delocalized over their ZCp ligand moieties (70-90%). Electron paramagnetic resonance (EPR) analysis of the isolated K[(PZCp)Mo(CO)3] and (PZCp)RuCp also indicated a high degree of ligand-localized radical character. Thus, the IZCp and PZCp ligands act as electron reservoirs to sustain these sandwich complexes in highly reduced states. At the same time, the CO stretching frequencies of K[(PZCp)Mo(CO)3]: νCO 1871, 1748, and 1699 cm-1, rank the [PZCp]- ligand as the strongest electron-donating Cp ligand among the reported CpMo(CO)3 derivatives, whose νCO > 1746 cm-1. In addition, these redox non-innocent Cps were obtained in high yields and found to be practically air- and moisture-stable, unlike typical Cps.

In-depth correlation analysis between tear glucose and blood glucose using a wireless smart contact lens

Tears have emerged as a promising alternative to blood for diagnosing diabetes. Despite increasing attempts to measure tear glucose using smart contact lenses, the controversy surrounding the correlation between tear glucose and blood glucose still limits the clinical usage of tears. Herein, we present an in-depth investigation of the correlation between tear glucose and blood glucose using a wireless and soft smart contact lens for continuous monitoring of tear glucose. This smart contact lens is capable of quantitatively monitoring the tear glucose levels in basal tears excluding the effect of reflex tears which might weaken the relationship with blood glucose. Furthermore, this smart contact lens can provide an unprecedented level of continuous tear glucose data acquisition at sub-minute intervals. These advantages allow the precise estimation of lag time, enabling the establishment of the concept called 'personalized lag time'. This demonstration considers individual differences and is successfully applied to both non-diabetic and diabetic humans, as well as in animal models, resulting in a high correlation.

Reactive cutaneous capillary endothelial proliferation predicted the efficacy of camrelizumab in patients with recurrent/metastatic head and neck squamous cell carcinoma

BACKGROUND

Reactive cutaneous capillary endothelial proliferation (RCCEP), a special adverse event (AE) only observed in patients treated with camrelizumab, was reported to be correlated with the efficacy of camrelizumab in patients with advanced hepatocellular carcinoma. This study to analyze the possible correlation between the occurrence of RCCEP and efficacy of camrelizumab in patients with recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC).

MATERIAL AND METHODS

In this study, we retrospectively analyzed the efficacy and RCCEP occurrence of camrelizumab in 58 patients with R/M HNSCC in the Shanghai Ninth People's Hospital affiliated to Shanghai JiaoTong University School of Medicine between January 2019 and June 2022. Kaplan-Meier analysis was used to assess the correlation between the occurrence of RCCEP and the survival of enrolled patients, and COX multifactor analysis was adopted to evaluate associated factors that affected the efficacy of camrelizumab immunotherapy.

RESULTS

A significant correlation between the incidence of RCCEP and a higher objective response rate was observed in this study (p=0.008). The occurrence of RCCEP was associated with better median overall survival (17.0 months vs. 8.7 months, p<0.0001, HR=5.944, 95% CI:2.097-16.84) and better median progression-free survival (15.1 months vs. 4.0 months, p<0.0001, HR=4.329,95% CI:1.683-11.13). In COX multifactor analysis, RCCEP occurrence was also an independent prognostic factor affecting OS and PFS in patients with R/M HNSCC.

CONCLUSIONS

The occurrence of RCCEP can show a better prognosis, it could be used as a clinical biomarker to predict the efficacy of camrelizumab treatment.

On the use of thermal forces to probe kinesin's response to force

The stepping dynamics of cytoskeletal motor proteins determines the dynamics of cargo transport. In its native cellular environment, a molecular motor is subject to forces from several sources including thermal forces and forces ensuing from the interaction with other motors bound to the same cargo. Understanding how the individual motors respond to these forces can allow us to predict how they move their cargo when part of a team. Here, using simulation, we show that details of how the kinesin motor responds to small assisting forces-which, at the moment, are not experimentally constrained-can lead to significant changes in cargo dynamics. Using different models of the force-dependent detachment probability of the kinesin motor leads to different predictions on the run-length of the cargo they carry. These differences emerge from the thermal forces acting on the cargo and transmitted to the motor through the motor tail that tethers the motor head to the microtubule. We show that these differences appear for cargo carried by individual motors or motor teams, and use our findings to propose the use of thermal forces as a probe of kinesin's response to force in this otherwise inaccessible force regime.

Smart Contact Lenses as Wearable Ophthalmic Devices for Disease Monitoring and Health Management

The eye contains a complex network of physiological information and biomarkers for monitoring disease and managing health, and ocular devices can be used to effectively perform point-of-care diagnosis and disease management. This comprehensive review describes the target biomarkers and various diseases, including ophthalmic diseases, metabolic diseases, and neurological diseases, based on the physiological and anatomical background of the eye. This review also includes the recent technologies utilized in eye-wearable medical devices and the latest trends in wearable ophthalmic devices, specifically smart contact lenses for the purpose of disease management. After introducing other ocular devices such as the retinal prosthesis, we further discuss the current challenges and potential possibilities of smart contact lenses.

Radiation Oncology Practice Changes during the COVID-19 Pandemic

PURPOSE/OBJECTIVE(S)

The purpose of this study was to characterize the effects of institutional policies routine SARS-CoV-2 testing before treatment starts with mandatory quarantine periods for COVID-positive patients during the first year of the COVID19 pandemic across radiation oncology sections at our tertiary cancer center.

MATERIALS/METHODS

Electronic medical databases were queried to identify all patients treated with curative intent at a large urban cancer center and regional satellites a year prior to the pandemic (02/11/19-12/30/19; pre-pandemic) and the first year of the pandemic (03/11/20-12/30/20; post-pandemic). New treatment starts were filtered for those undergoing treatment under a single ICD-10 diagnosis and the first treatment in each time period for each patient. Chi-square tests were used for categorical variables, and the t-test was used for continuous variables to correlate differences in demographic and clinical factors before and during the pandemic.

RESULTS

The total number of new treatment starts were similar between the pre-pandemic (2,218 patients) and post-pandemic (2,130 patients) periods, but there was a 26% decrease in treatments in April 2020 compared to April 2019 and a 40% increase in treatments in November 2020 compared to November 2019. Post-pandemic patients had higher minimum Charlson Comorbidity Index scores (mean 46.0 vs 42.6, P = 0.0013) and were younger (62.8 yo vs 64.3 yo, P = 0.0001). The proportion of patients being treated from the same state as our institution was higher in the post-pandemic period compared to pre-pandemic (77.8% vs 72.43%, P = 0.0259). Distribution of treatments across department disease-site sections were significantly different (P<0.0001), with the proportion of patients treated by the Breast service having increased by 22% whereas the metropolitan area regional satellites experienced a 18% reduction. There were no statistically significant differences amongst pre- and post-pandemic patients with respect to race, marital status, or smoking status. Post-pandemic patients had less total radiation-related clinical visits (mean 24.8 vs 28.6, P<0.0001), lower administered dose (4329 cGy vs 4533 cGy, P<0.0001), and lower radiation fraction count (17 vs 19, P<0.0001). There was no statistically significant difference in the duration between CT simulation and treatment start, but post-pandemic patients had shorter duration of elapsed days during treatment (27 days vs 29 days, P = 0.0001). A disease-site-specific analysis demonstrated that these differences were most pronounced in patients treated for breast cancer.

CONCLUSION

In the first year of the COVID19 pandemic, our institution saw a dynamic change in the number of new radiation treatments. Additional analyses across individual disease-specific services may reveal insight into dose, fractionation, and technique, which may account for the observed differences.

Phase II study of a trastuzumab biosimilar in combination with paclitaxel for HER2-positive recurrent or metastatic urothelial carcinoma: KCSG GU18-18

BACKGROUND

Human epidermal growth factor receptor 2 (HER2) is a widely explored therapeutic target in solid tumors. We evaluated the efficacy and safety of trastuzumab-pkrb, a biosimilar of trastuzumab, in combination with paclitaxel, in HER2-positive recurrent or metastatic urothelial carcinoma (UC).

PATIENTS AND METHODS

We enrolled 27 patients; they were administered a loading dose of 8 mg/kg trastuzumab-pkrb on day 1, followed by 6 mg/kg and 175 mg/m2 paclitaxel on day 1 every 3 weeks, intravenously. All patients received six cycles of the combination treatment and continued to receive trastuzumab-pkrb maintenance until disease progression, unacceptable toxicity, or for up to 2 years. HER2 positivity (based on immunohistochemistry analysis) was determined according to the 2013 American Society of Clinical Oncology /College of American Pathologists HER2 testing guidelines. The primary endpoint was objective response rate (ORR); the secondary endpoints were overall survival (OS), progression-free survival (PFS), and safety.

RESULTS

Twenty-six patients were evaluated via primary endpoint analysis. The ORR was 48.1% (1 complete and 12 partial responses) and the duration of response was 6.9 months [95% confidence interval (CI) 4.4-9.3 months]. With a median follow-up of 10.5 months, the median PFS and OS were 8.4 months (95% CI 6.2-8.8 months) and 13.5 months (95% CI 9.8 months-not reached), respectively. The most common treatment-related adverse event (TRAE) of any grade was peripheral neuropathy (88.9%). The most common grade 3/4 TRAEs were neutropenia (25.9%), thrombocytopenia (7.4%), and anemia (7.4%).

CONCLUSIONS

Trastuzumab-pkrb plus paclitaxel demonstrates promising efficacy with manageable toxicity profiles in patients with HER2-positive recurrent or metastatic UC.

[Pathological classification of malignant peritoneal mesothelioma and comparative analysis with peritoneal carcinomatosis]

Objective: To analyze the pathological classification of malignant peritoneal mesothelioma (MPeM) and screen the immunohistochemical markers that can distinguish MPeM from peritoneal metastatic carcinoma (PC) . Methods: In June 2020, the pathological results of peritoneal biopsy of 158 MPeM and 138 PC patients from Cangzhou Central Hospital, Cangzhou People's Hospital, and Cangzhou Hospital of Integrated Traditional Chinese and Western Medicine from May 2011 to July 2019 were retrospectively analyzed, and the pathological classifications of MPeM in Cangzhou were summarized. Immunohistochemical markers of MPeM and PC patients were analyzed, and receiver operating characteristic curve (ROC curve) was drawn for differential diagnosis of MPeM and PC. Results: There were 55 male and 103 female MPeM patients in Cangzhou, with an average age of 57.1 years old. The asbestos exposure rate was 91.14% (144/158). The most common pathological classifications were cutaneous type, accounting for 90.51% (143/158). There were significant differences in the expression of calreticulum protein, CK5/6, vimentin, D2-40, carcinoembryonic antigen (CEA) and tail type homologous nuclear gene transcription factor 2 (CDX-2) between MPeM and PC (P<0.05). Among the 6 positive markers, the sensitivity of calreticulum protein was the highest (0.905) and CEA was the lowest (0.428) . Conclusion: Calreticulum protein, CK5/6, vimentin, D2-40, CEA and CDX-2 may be used as specific markers to distinguish the diagnosis of MPeM from PC.

Large-scale neural dynamics in a shared low-dimensionalstate space reflect cognitive and attentional dynamics

Cognition and attention arise from the adaptive coordination of neural systems in response to external and internal demands. The low-dimensional latent subspace that underlies large-scale neural dynamics and the relationships of these dynamics to cognitive and attentional states, however, are unknown. We conducted functional magnetic resonance imaging as human participants performed attention tasks, watched comedy sitcom episodes and an educational documentary, and rested. Whole-brain dynamics traversed a common set of latent states that spanned canonical gradients of functional brain organization, with global desynchronization among functional networks modulating state transitions. Neural state dynamics were synchronized across people during engaging movie watching and aligned to narrative event structures. Neural state dynamics reflected attention fluctuations such that different states indicated engaged attention in task and naturalistic contexts whereas a common state indicated attention lapses in both contexts. Together, these results demonstrate that traversals along large-scale gradients of human brain organization reflect cognitive and attentional dynamics.

Formation of Highly Stable 1,2-Dicarbonyl Organic Radicals from Cyclic (Alkyl)(amino)carbenes

Two air-stable organic radicals derived from oxalyl chloride and cAAC were synthesized, resulting in the unexpected formation of a known (amino)(carboxy) radical cation ([2]BF₄) and the oxidative formation of a 1,2-dicarbonyl radical cation ([3]BF₄) from a neutral 3-oxetanone compound (4). The highly strained and newly discovered 4 was obtained by a single-electron reduction of [3]BF₄ with a mild reducing agent. This result differs from the generation of NHC-based 1,2-dicarbonyl radicals, indicating the uniqueness of cAAC.

Triplex metallohelices have enantiomer-dependent mechanisms of action in colon cancer cells

Self-assembled enantiomers of an asymmetric di-iron metallohelix differ in their antiproliferative activities against HCT116 colon cancer cells such that the compound with Λ-helicity at the metals becomes more potent than the Δ compound with increasing exposure time. From concentration- and temperature-dependent ⁵⁷Fe isotopic labelling studies of cellular accumulation we postulate that while the more potent Λ enantiomer undergoes carrier-mediated efflux, for Δ the process is principally equilibrative. Cell fractionation studies demonstrate that both enantiomers localise in a similar fashion; compound is observed mostly within the cytoskeleton and/or genomic DNA, with significant amounts also found in the nucleus and membrane, but with negligible concentration in the cytosol. Cell cycle analyses using flow cytometry reveal that the Δ enantiomer induces mild arrest in the G₁ phase, while Λ causes a very large dose-dependent increase in the G₂/M population at a concentration significantly below the relevant IC₅₀. Correspondingly, G₂-M checkpoint failure as a result of Λ-metallohelix binding to DNA is shown to be feasible by linear dichroism studies, which indicate, in contrast to the Δ compound, a quite specific mode of binding, probably in the major groove. Further, spindle assembly checkpoint (SAC) failure, which could also be responsible for the observed G₂/M arrest, is established as a feasible mechanism for the Λ helix via drug combination (synergy) studies and the discovery of tubulin and actin inhibition. Here, while the Λ compound stabilizes F-actin and induces a distinct change in tubulin architecture of HCT116 cells, Δ promotes depolymerization and more subtle changes in microtubule and actin networks.

Revisiting the Reaction of IPr with Tritylium: An Alternative Mechanistic Pathway

Despite a recent proposal on the mechanism of a single-electron transfer (SET) process between tritylium and 2,6-bis(diisopropylphenyl)imidazol-2-ylidene (IPr) based on evidence of transient IPr radical cation intermediate ([IPr]⋅⁺ ) formation, such oxidation is still contentious because of the high oxidation potential of N-heterocyclic carbenes. Our experimental analysis indicates that the appearance of deep purple color, previously considered to be from transient [IPr]⋅⁺ , originates from a zwitterionic intermediate (3 a), not a radical cation. Here, we propose an alternative mechanism for the reaction involving tritylium and IPr. This mechanism is noteworthy for explaining how [NHC-H]⁺ can be generated without the formation of transient [NHC]⋅⁺ , which has been frequently proposed as an intermediate for the reaction between NHC and oxidants. These results also show that a transient strong single-electron donor (3 a) could be generated by the alternative mechanism for oxidants using NHCs, which is a more feasible explanation for the reactivity of NHCs with oxidants.

Search for the Majorana Nature of Neutrinos in the Inverted Mass Ordering Region with KamLAND-Zen

The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νββ) decay half-life in ^{136}Xe using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of ^{136}Xe. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νββ decay half-life of T_{1/2}^{0ν}>2.3×10^{26}  yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.

Compact high repetition rate Thomson parabola ion spectrometer

We present the development of a compact Thomson parabola ion spectrometer capable of characterizing the energy spectra of various ion species of multi-MeV ion beams from >10²⁰W/cm² laser produced plasmas at rates commensurate with the highest available from any of the current and near-future PW-class laser facilities. This diagnostic makes use of a polyvinyl toluene based fast plastic scintillator (EJ-260), and the emitted light is collected using an optical imaging system coupled to a thermoelectrically cooled scientific complementary metal-oxide-semiconductor camera. This offers a robust solution for data acquisition at a high repetition rate, while avoiding the added complications and nonlinearities of micro-channel plate based systems. Different ion energy ranges can be probed using a modular magnet setup, a variable electric field, and a varying drift-distance. We have demonstrated operation and data collection with this system at up to 0.2 Hz from plasmas created by irradiating a solid target, limited only by the targeting system. With the appropriate software, on-the-fly ion spectral analysis will be possible, enabling real-time experimental control at multi-Hz repetition rates.

Plastic wastes in the time of COVID-19: Their environmental hazards and implications for sustainable energy resilience and circular bio-economies

The global scope of pollution from plastic waste is a well-known phenomenon associated with trade, mass consumption, and disposal of plastic products (e.g., personal protective equipment (PPE), viral test kits, and vacuum-packaged food). Recently, the scale of the problem has been exacerbated by increases in indoor livelihood activities during lockdowns imposed in response to the coronavirus disease 2019 (COVID-19) pandemic. The present study describes the effects of increased plastic waste on environmental footprint and human health. Further, the technological/regulatory options and life cycle assessment (LCA) approach for sustainable plastic waste management are critically dealt in terms of their implications on energy resilience and circular economy. The abrupt increase in health-care waste during pandemic has been worsening environmental quality to undermine the sustainability in general. In addition, weathered plastic particles from PPE along with microplastics (MPs) and nanoplastics (NPs) can all adsorb chemical and microbial contaminants to pose a risk to ecosystems, biota, occupational safety, and human health. PPE-derived plastic pollution during the pandemic also jeopardizes sustainable development goals, energy resilience, and climate control measures. However, it is revealed that the pandemic can be regarded as an opportunity for explicit LCA to better address the problems associated with environmental footprints of plastic waste and to focus on sustainable management technologies such as circular bio-economies, biorefineries, and thermal gasification. Future researches in the energy-efficient clean technologies and circular bio-economies (or biorefineries) in concert with a "nexus" framework are expected to help reduce plastic waste into desirable directions.

A flexible proton beam imaging energy spectrometer (PROBIES) for high repetition rate or single-shot high energy density (HED) experiments (invited)

The PROBIES diagnostic is a new, highly flexible, imaging and energy spectrometer designed for laser-accelerated protons. The diagnostic can detect low-mode spatial variations in the proton beam profile while resolving multiple energies on a single detector or more. When a radiochromic film stack is employed for "single-shot mode," the energy resolution of the stack can be greatly increased while reducing the need for large numbers of films; for example, a recently deployed version allowed for 180 unique energy measurements spanning ∼3 to 75 MeV with <0.4 MeV resolution using just 20 films vs 180 for a comparable traditional film and filter stack. When utilized with a scintillator, the diagnostic can be run in high-rep-rate (>Hz rate) mode to recover nine proton energy bins. We also demonstrate a deep learning-based method to analyze data from synthetic PROBIES images with greater than 95% accuracy on sub-millisecond timescales and retrained with experimental data to analyze real-world images on sub-millisecond time-scales with comparable accuracy.

A novel cardiac arrest severity score for the early prediction of hypoxic-ischemic brain injury and in-hospital death

Funding Acknowledgements

Type of funding sources: None.

Background

Out-of-hospital cardiac arrest (OHCA) outcomes are unsatisfactory despite postcardiac arrest care. Early prediction of prognoses might help stratify patients and provide tailored therapy.

Purpose

In this study, we derived and validated a novel scoring system to predict hypoxic-ischaemic brain injury (HIBI) and in-hospital death (IHD).

Methods

We retrospectively analysed Korean Hypothermia Network prospective registry data collected from in Korea between 2015 and 2018. Patients without neuroprognostication data were excluded, and the remaining patients were randomly divided into derivation and validation cohorts. HIBI was defined when at least one prognostication predicted a poor outcome. IHD meant all deaths regardless of cause. In the derivation cohort, stepwise multivariate logistic regression was conducted for HIBI and IHD scores, and model performance was assessed. We then classified patients into four categories and analysed associations between the categories and cerebral performance categories (CPCs) at hospital discharge. Finally, we validated our models in the internal validation cohort.

Results

Among 1373 patients, 240 were excluded, and 1133 were randomised into derivation (n=754) and validation cohorts (n=379). In the derivation cohort, 7 and 8 predictors were selected for HIBI (0–8) and IHD scores (0–11), respectively, and the area under the curve (AUC) was 0.85 (95% CI 0.82–0.87) and 0.80 (95% CI 0.77–0.82), respectively. Applying optimum cutoff values of ≥6 points for HIBI and ≥7 points for IHD, patients were classified as follows: HIBI (-)/IHD (-), Category 1 (n=424); HIBI (-)/IHD (+), Category 2 (n=100); HIBI (+)/IHD (-), Category 3 (n=21); and HIBI (+)/IHD (+), Category 4 (n=209). CPCs at discharge were significantly different in each category (p&lt;0.001). In the validation cohort, the model showed moderate discrimination (AUC 0.83, 95% CI 0.79–0.87 for HIBI and AUC 0.77, 95% CI 0.72–0.81 for IHD) with good calibration. Each category of the validation cohort showed a significant difference in discharge outcomes (p&lt;0.001) and a similar trend to the derivation cohort.

Conclusions

We presented a novel approach for assessing illness severity after OHCA. Although external prospective studies are warranted, risk stratification for HIBI and IHD could help provide OHCA patients with appropriate treatment.

Novel serum biomarkers for predicting prognosis in post cardiac arrest patients

Funding Acknowledgements

Type of funding sources: None.

Objective

To determine the clinical feasibility of novel serum biomarkers by comparing them with conventional serum biomarkers in out-of-hospital cardiac arrest (OHCA) patients treated with target temperature management (TTM).

Methods

This study was a prospective observational study conducted on OHCA patients who underwent TTM. We measured serum biomarker Neuron‑Specific Enolase (NSE), S-100B (S100 calcium-binding protein), Tau protein, Glial Fibrillary Acidic Protein (GFAP), Neurofilament Light Chain (NFL), and Ubiquitin C-terminal hydrolase-L1 (UCH-L1) at 0, 24, 48, and 72 hours after return of spontaneous circulation (ROSC). Conventional biomarkers include NSE and S-100B. The primary outcome was good neurologic outcome at 6 months after OHCA.

Results

A total of 100 patients were included in this study from August 2018 to May 2020. Among the included patients, 46 patients had good neurologic outcomes. As for the biomarker's AUC value measured immediately after ROSC, GFAP had the highest value (0.850), and among the values measured 24 hours after ROSC, S100B showed the highest value (0.901). The AUC values of biomarkers measured after 48 hours and 72 hours after ROSC, were the highest in NFL (0.921, 0.946). AUC values measured after 72 hours of ROSC showed higher values in novel biomarkers than in conventional biomarkers.

Conclusion

After 72 hours of ROSC, the Novel biomarkers showed a higher AUC value than the conventional biomarkers. Among them, NFL showed the highest AUC values than other biomarkers at 48 and 72 hours of ROSC.

A Multicentre Clinical Study of Sarcoma Personalised Treatment Using Patient-Derived Tumour Xenografts

AIMS

Medication for advanced sarcomas has not improved for three decades. Patient-derived tumour xenografts (PDTX) are a promising solution for developing new therapies and real-time personalised medicine because of their highly effective prediction of drug efficacy. However, there is a dearth of PDTX models for sarcomas due to the scarcity and heterogeneity of the disease.

MATERIALS AND METHODS

A multicentre clinical collaborative study (ChiCTR-OOC-17013617) was carried out. Fresh patient tumour tissues via resection or biopsy were used for the PDTX set-up. The standard medical care chosen by the physician was given to the patient, in parallel with testing on multiple regimens. The outcomes of patients' responses and PDTX tests were compared. Comprehensive analyses were carried out to assess the clinical value of PDTX for the treatment of sarcomas. Living tissues from successfully engrafted cases were deposited into a repository.

RESULTS

Forty-two cases, including 36 bone sarcomas and six soft-tissue sarcomas, were enrolled; the overall engraftment rate was 73.8%. Histopathological examination showed a 100% consistency between primary tumours and tumour grafts. The engraftment rate was independent of age, gender and sampling methods, but was associated with subtypes of tumour. The outgrowth time of tumour grafts could be associated with prognosis. Major somatic mutations in tumour grafts occurred primarily in common tumour driver genes. Poor prognosis was associated with the KMT2C mutation. A drug efficacy test showed complete concordance between the PDTX model and patients' responses in 17 regimens.

CONCLUSION

PDTX is an ideal preclinical model for sarcomas because of its faithful preservation of the heterogeneity of the disease, a satisfactory engraftment rate and high accuracy in its prediction of drug efficacy.

Age-related hearing loss was accelerated by apoptosis of spiral ganglion and stria vascularis cells in ApoE KO mice with hyperglycemia and hyperlipidemia

Age-related hearing loss (ARHL) is associated with diabetes and/or dyslipidemia in humans. However, the detailed mechanism for the development of ARHL by diabetes and/or dyslipidemia has not been elucidated. In this study, we investigated the etiology of ARHL in apolipoprotein E (ApoE)-deficient mice with diabetes and dyslipidemia. The atherosclerotic CD-STZ (mice fed with a control diet and received an STZ injection), WD-con (mice fed with a western diet), and WD-STZ (mice fed with a western diet and received an STZ injection) mice showed a 2.4-, 4.9-, and 6.8-fold larger area, respectively, occupied by lesions throughout the aorta compared with the CD-con mice. A significantly larger area under the curve (AUC) was observed in the STZ-treated groups than in the non-treated groups based on the oral glucose tolerance test (OGTT). At 20 weeks of age, HbA_1c levels were significantly higher in the CD-STZ and WD-STZ mice than in the CD-con and WD-con mice. In all the groups, the auditory brainstem response (ABR) thresholds of the 16-week-old mice were significantly higher compared with those of the 8-week-old mice. In particular, in the WD-STZ mice, the ABR thresholds of the left and right ears reached the maximum decibel peak equivalent sound pressure levels (130 dBpeSPL), which is a sign of deafness. The apoptotic spiral ganglion neurons (SGNs) of the WD-STZ mice were significantly increased compared with those of the other three groups, indicating that SGN apoptosis resulted in hearing loss in STZ-induced diabetic ApoE KO mice fed with a WD. A significant loss of the stria vascularis cells was observed in the WD-STZ group compared with the CD-con mice. In the organ of Corti, few apoptotic hair cells were found in all the groups; however, no significant difference was observed. Therefore, we consider that the reduced hearing ability in the STZ-treated and WD-fed groups was attributed to the damage to the SGN and stria vascularis in the cochlea. Thus, our results indicated that ototoxicity by diabetes and/or dyslipidemia accelerated ARHL in ApoE KO mice, thereby suggesting the importance of appropriate treatment of patients with diabetes and/or dyslipidemia to prevent ARHL.

Ultra-compact x-ray spectrometer for high-repetition-rate laser-plasma experiments

We present in this work the development of an ultra-compact, multi-channel x-ray spectrometer (UCXS). This diagnostic has been specially built and adapted to perform at high-repetition-rate (>1 Hz) for high-intensity, short-pulse laser plasma experiments. X-ray filters of varying materials and thicknesses are chosen to provide spectral resolution up to ΔE ≈ 1 keV over the x-ray energy range of 1-30 keV. These filters are distributed over a total of 25 channels, where each x-ray filter is coupled to a single scintillator. The UCXS is designed to detect and resolve a large variety of laser-driven x-ray sources such as low energy bremsstrahlung emission, fluorescence, and betatron radiation (up to 30 keV). Preliminary results from commissioning experiments at the ABL laser facility at Colorado State University are provided.

Hospital procedural volume and clinical outcomes for transcatheter aortic valve replacement – US nationwide readmission database, 2016–2019

Background

The number of hospitals offering transcatheter aortic valve replacement (TAVR) programs has increased exponentially in the United States over past several years. Multiple prior studies indicate relationship between hospital volume and clinical outcomes for various cardiac procedures.

Purpose

The association between the hospital procedural volume and clinical outcomes for TAVR is yet poorly understood. In this study, we aim to examine the in-hospital outcomes after TAVR stratified by hospital volume within a nationally representative, large database.

Methods

The National Readmission Database (NRD) 2016–2019 was used to identify hospitals with established TAVR programs (performing ≥20 TAVRs/year). Based on annualized procedural volume of transfemoral TAVR, hospitals were stratified into tertiles of low, medium, and high volume TAVR centers. Rates of adverse in-hospital events (death, cardiac arrest, stroke, vascular complications, and permanent pacemaker), 30-day mortality, and 30-day readmission rates were examined. Multivariate logistic regression analysis was performed to compare overall outcomes following TAVR in low-, medium-, and high-volume centers; adjusted for baseline characteristics and comorbidity burden.

Results

Of 71 million discharge records reviewed, a total of 232,581 patients underwent transfemoral TAVR between 2016–2019. Of all the TAVR cases, 77,183 (33.2%), 75,987 (32.7%), and 79,411 (34.1%) were performed at low-, medium-, and high-volume hospitals respectively. The median number of annual TAVR procedures was 91, 229, and 456 in low-, medium-, and high-volume centers respectively. Adjusted in-hospital mortality was significantly higher in low-volume (OR: 1.40, 95% CI: 1.21–1.62, p&lt;0.01) and medium-volume (OR: 1.29, 95% CI: 1.11–1.50, p&lt;0.01) hospitals compared with high-volume centers. Similarly, adjusted 30-day mortality (OR: 1.45, 95% CI: 1.27–1.66, p&lt;0.01), 30-day readmission rates (OR: 1.11, 95% CI: 1.05–1.18, p&lt;0.01), and in-hospital cardiac arrest (OR: 1.20, 95% CI: 1.08–1.33, p&lt;0.01) were significantly higher for centers in the lowest-volume tertile compared with those in the highest-volume tertile. There were no significant differences in hospital length of stay (mean, 4.3±6.5 days), in-hospital stroke, acute kidney injury, vascular complications, need for permanent pacemaker, or mechanical circulatory support post-TAVR between the three groups.

Conclusion

In the United States, an inverse volume-mortality relationship was observed for transfemoral TAVR procedures from 2016 through 2019. Mortality and readmission rates at 30 days post-TAVR were significantly higher at low-volume hospitals compared with high-volume hospitals. Further research focusing at establishing protocols and standardized training programs may help mitigate the discrepancy in TAVR outcomes amongst hospitals with discrepant procedural volume.

Funding Acknowledgement

Type of funding sources: None.

Applications of machine learning to a compact magnetic spectrometer for high repetition rate, laser-driven particle acceleration

Accurately and rapidly diagnosing laser-plasma interactions is often difficult due to the time-intensive nature of the analysis and will only become more so with the rise of high repetition rate lasers and the desire to implement feedback on a commensurate timescale. Diagnostic analysis employing machine learning techniques can help address this problem while maintaining a high degree of accuracy. We report on the application of machine learning to the analysis of a scintillator-based electron spectrometer for experiments on high intensity, laser-plasma interactions at the Colorado State University Advanced Lasers and Extreme Photonics facility. Our approach utilizes a neural network trained on synthetic data and tested on experiments to extract the accelerated electron temperature. By leveraging transfer learning, we demonstrate an improvement in the neural network accuracy, decreasing the network error by 50%.