New insights into aging in LiNiO2 cathodes from high resolution paramagnetic NMR spectroscopy

Bulk degradation processes are examined in the LiNiO2 cathode using high resolution solid-state NMR, combined with magnetometry and X-ray diffraction. Capacity decay is correlated with bulk heterogeneity, whereby multiple structural domains coexist in the charged state, and the Li content and electrochemical activity of these domains is unraveled for the first time.

Tumour size predicts risk of recurrence in tall cell subtype papillary thyroid carcinoma

BACKGROUND

The tall cell subtype of papillary thyroid cancer (TCPTC) is the most common aggressive subtype and often treated aggressively. This approach may not be necessary in smaller tumours without adverse histological characteristics.

METHODS

97 patients with TCPTC defined as a height-to-width ratio of ≥3:1 and at least 30% tall cells were compared against 390 classical papillary thyroid carcinoma (CPTC) based on tumour size with recurrence free survival (RFS) as the primary outcome.

RESULTS

TCPTC are more likely to present with adverse histological characteristics. In smaller tumours (<2 ​cm), only central lymph node metastasis (HR7.16 p ​= ​0.03) and multifocality (HR10.11 p ​= ​0.026) increased recurrence risk. In larger tumours, TCPTC histology (HR3.78 p ​= ​0.002), lymphovascular invasion (HR3.02 p ​= ​0.014) and central lymph node metastasis (HR3.24 p ​< ​0.001) significantly increased recurrence risk.

CONCLUSION

TCPTC tumours <2 ​cm without central lymph node metastasis and multifocality are similar in risk of recurrence to classical PTC and could be managed with lobectomy.

Utility of multimodal longitudinal imaging data for dynamic prediction of cardiovascular and renal disease: the CARDIA study

Background

Medical examinations contain repeatedly measured data from multiple visits, including imaging variables collected from different modalities. However, the utility of such data for the prediction of time-to-event is unknown, and only a fraction of the data is typically used for risk prediction. We hypothesized that multimodal longitudinal imaging data could improve dynamic disease prognosis of cardiovascular and renal disease (CVRD).

Methods

In a multi-centered cohort of 5,114 CARDIA participants, we included 166 longitudinal imaging variables from five imaging modalities: Echocardiography (Echo), Cardiac and Abdominal Computed Tomography (CT), Dual-Energy x-ray Absorptiometry (DEXA), Brain Magnetic Resonance Imaging (MRI) collected from young adulthood to mid-life over 30 years (1985-2016) to perform dynamic survival analysis of CVRD events using machine learning dynamic survival analysis (Dynamic-DeepHit, LTRCforest, and Extended Cox for Time-varying Covariates). Risk probabilities were continuously updated as new data were collected. Model performance was assessed using integrated AUC and C-index and compared to traditional risk factors.

Results

Longitudinal imaging data, even when being irregularly collected with high missing rates, improved CVRD dynamic prediction (0.03 in integrated AUC, up to 0.05 in C-index compared to traditional risk factors; best model's C-index = 0.80-0.83 up to 20 years from baseline) from young adulthood followed up to midlife. Among imaging variables, Echo and CT variables contributed significantly to improved risk estimation. Echo measured in early adulthood predicted midlife CVRD risks almost as well as Echo measured 10-15 years later (0.01 C-index difference). The most recent CT exam provided the most accurate prediction for short-term risk estimation. Brain MRI markers provided additional information from cardiac Echo and CT variables that led to a slightly improved prediction.

Conclusions

Longitudinal multimodal imaging data readily collected from follow-up exams can improve CVRD dynamic prediction. Echocardiography measured early can provide a good long-term risk estimation, while CT/calcium scoring variables carry atherosclerotic signatures that benefit more immediate risk assessment starting in middle-age.

Homogeneous crystallization and buried interface passivation for perovskite tandem solar modules

Scalable fabrication of all-perovskite tandem solar cells is challenging because the narrow-bandgap subcells made of mixed lead-tin (Pb-Sn) perovskite films suffer from nonuniform crystallization and inferior buried perovskite interfaces. We used a dopant from Good's list of biochemical buffers, aminoacetamide hydrochloride, to homogenize perovskite crystallization and used it to extend the processing window for blade-coating Pb-Sn perovskite films and to selectively passivate defects at the buried perovskite interface. The resulting all-perovskite tandem solar module exhibited a certified power conversion efficiency of 24.5% with an aperture area of 20.25 square centimeters.

Comparison between U-shaped structural deep learning models to detect landslide traces

Landslides endanger lives and public infrastructure in mountainous areas. Monitoring landslide traces in real-time is difficult for scientists, sometimes costly and risky because of the harsh terrain and instability. Nowadays, modern technology may be able to identify landslide-prone locations and inform locals for hours or days when the weather worsens. This study aims to propose indicators to detect landslide traces on the fields and remote sensing images; build deep learning (DL) models to identify landslides from Sentinel-2 images automatically; and apply DL-trained models to detect this natural hazard in some particular areas of Vietnam. Nine DL models were trained based on three U-shaped architectures, including U-Net, U2-Net, and U-Net3+, and three options of input sizes. The multi-temporal Sentinel-2 images were chosen as input data for training all models. As a result, the U-Net, using an input image size of 32 × 32 and a performance of 97 % with a loss function of 0.01, can detect typical landslide traces in Vietnam. Meanwhile, the U-Net (64 × 64) can detect more considerable landslide traces. Based on multi-temporal remote sensing data, a different case study in Vietnam was chosen to see landslide traces over time based on the trained U-Net (32 × 32) model. The trained model allows mountain managers to track landslide occurrences during wet seasons. Thus, landslide incidents distant from residential areas may be discovered early to warn of flash floods.

Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

High inductance magnetic-core coils have enhanced efficiency in inducing suprathreshold motor response in rats

Objective. Transcranial magnetic stimulation (TMS) coil design involves a tradeoff among multiple parameters, including magnetic flux density (B), inductance (L), induced electric (E) field, focality, penetration depth, coil heating, etc. Magnetic materials with high permeability have been suggested to enhance coil efficiency. However, the introduction of magnetic core invariably increases coil inductance compared to its air-core counterpart, which in turn weakens theEfield. Our lab previously reported a rodent-specific TMS coil with silicon steel magnetic core, achieving 2 mm focality. This study aims to better understand the tradeoffs amongB,L,andEin the presence of magnetic core.Approach. The magnetic core initially operates within the linear range, transitioning to the nonlinear range when it begins to saturate at high current levels and reverts to the linear range as coil current approaches zero; both linear and nonlinear analyses were performed. Linear analysis assumes a weak current condition when magnetic core is not saturated; a monophasic TMS circuit was employed for this purpose. Nonlinear analysis assumes a strong current condition with varying degrees of core saturation.Main results. Results reveal that, the secondaryEfield generated by the silicon steel core substantially changed the dynamics during TMS pulse. Linear and nonlinear analyses revealed that higher inductance coils produced stronger peakEfields and longerEfield waveforms. On a macroscopic scale, the effects of these two factors on neuronal activation could be conceptually explained through a one-time-constant linear membrane model. Four coils with differentB,L,andEcharacteristics were designed and constructed. BothEfield mapping and experiments on awake rats confirmed that inductance could be much higher than previously anticipated, provided that magnetic material possesses a high saturation threshold.Significance. Our results highlight the novel potentials of magnetic core in TMS coil designs, especially for small animals.

Feasibility, tolerability and efficacy of the ketogenic diet in children with drug-resistant epilepsy in Vietnam

OBJECTIVES

According to the WHO, more than 50 million people have epilepsy. Among them, nearly 80% of patients with epilepsy live in developing countries and 75% of them do not have access to treatment. The ketogenic diet (KD) has been shown as an effective alternative for patients with drug-resistant epilepsy. Although it has been studied in Asia, no such studies have been conducted in Vietnam. The purpose of this study was to verify the feasibility and tolerability of KD in children with refractory epilepsies in Vietnam.

METHODS

Children with drug-resistant epilepsy followed at Children's Hospital, Vietnam treated by KD were included in a prospective study from June 2019 to October 2021. Side-effects, retention rate, number, and duration of seizures were recorded after 1, 3, 6, 9 and 12 months of KD. Patients were considered as respondents when a 50% seizure frequency was reached. Tolerance and acceptability of the KD were closely monitored.

RESULTS

Forty-six children were included but KD was contraindicated for one patient. Due to the COVID pandemic, we had to rely on internet exchanges to stay in touch with families. Meals had to be adapted to Vietnamese culinary habits. The retention rate decreased from 82.2% at 1 month to 40% at 12 months of follow-up. The incidence of side effects was 44.4% and occurred mainly during the first month. Fifteen patients out of 45 were considered as responders after 12 months.

SIGNIFICANCE

Our study was the first attempt to introduce KD in Vietnam. It demonstrated that this diet was feasible and well tolerated. The KD diet resulted in significant improvement for 30% of our patients with drug-resistant epilepsy. This percentage is lower than in some studies but warrants the use of KD as a valuable alternative in a country where many patients lack access to recent treatments.

Minimal invasive plate osteosynthesis for the dislocated humeral head fracture associated with ipsilateral humeral shaft fracture: A case report

The condition combining a dislocated humeral head fracture and an ipsilateral humeral shaft fracture is seen to be rare in literature, which is limited to case report or case series. Furthermore, effective management of these coexistent injuries is still a subject of debate. The essential purpose of this article is to report another treatment method for this condition. We present a case of a 79-year-old female patient who suffered a three-part humeral head fracture-dislocation associated with the ipsilateral humeral shaft fracture. The combined injuries were managed by minimal invasive plate osteosynthesis (MIPO) through the deltopectoral approach with the eventual result of bone healing and good function after thirty-three months of follow-up. In conclusion, MIPO should be considered a safe and effective option, however, the risk of traumatic osteonecrosis of the humeral head is taken into account before operation decision-making.

Low levels of mouse sperm chromatin fragmentation delay embryo development

We previously demonstrated that MnCl2 induces double-stranded DNA breaks in sperm in a process that we term as sperm chromatin fragmentation. Here, we tested if the levels of double-stranded DNA breaks were corelated to the concentration of MnCl2, and we compared this to another agent that causes single-stranded DNA breaks, H2O2. We found that both methods have the advantage of inducing DNA breaks in a concentration-dependent manner. Mouse sperm were treated with varying concentrations of either H2O2 or MnCl2, and the DNA damage was assessed by pulse-field gel electrophoresis, and the alkaline and neutral comet assays. Oocytes were injected with either treated sperm and the resulting embryos analyzed with an embryoscope to detect subtle changes in embryonic development. We confirmed that H2O2 treatment induced primarily single-stranded DNA breaks and MnCl2 induced primarily double-stranded DNA breaks, indicating different mechanisms of damage. These sperm were injected into oocytes, and the development of the resulting embryos followed with an embryoscope equipped with time lapse recording. We found that aberrations in early embryonic development by day 2 with even the lowest levels of DNA damage and that the levels of embryonic aberrations correlated to the concentration of either H2O2 or MnCl2. Low levels of H2O2 caused significantly more aberrations in embryonic development than low levels of MnCl2 even though the levels of DNA damage as measured by comet assays were similar. These data demonstrate that even low levels of sperm DNA damage cause delays and arrests in embryonic development.

Effect of the L74I Polymorphism on Fitness of Cabotegravir-Resistant Variants of Human Immunodeficiency Virus 1 Subtype A6

The presence of human immunodeficiency virus (HIV) 1 subtype A6, characterized by the L74I integrase (IN) polymorphism, is associated with confirmed virologic failure in clinical trials of long-acting cabotegravir and rilpivirine. We investigated the effect of L74I on replication capacity (RC) of recombinant viruses carrying this polymorphism in combination with various IN stand-transfer inhibitor resistance mutations. The presence of L74I conferred greater RC to recombinant viruses expressing HIV-1 A6 IN when present together with G118R, G140R, Q148H, and R263K; no significant difference in RC was observed for the Q148K or R mutants. These findings may explain, in part, the association of HIV-1 subtype A6 with virologic failure.

Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm

We present a new measurement of the positive muon magnetic anomaly, a_{μ}≡(g_{μ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From the ratio ω_{a}/ω[over ˜]_{p}^{'}, together with precisely determined external parameters, we determine a_{μ}=116 592 057(25)×10^{-11} (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain a_{μ}(FNAL)=116 592 055(24)×10^{-11} (0.20 ppm). The new experimental world average is a_{μ}(exp)=116 592 059(22)×10^{-11} (0.19 ppm), which represents a factor of 2 improvement in precision.

Brain Functional Connectome Defines a Transdiagnostic Dimension Shared by Cognitive Function and Psychopathology in Preadolescents

BACKGROUND

Cognitive function and general psychopathology are two important classes of human behavior dimensions that are individually related to mental disorders across diagnostic categories. However, whether these two transdiagnostic dimensions are linked to common or distinct brain networks that convey resilience or risk for the development of psychiatric disorders remains unclear.

METHODS

The current study is a longitudinal investigation with 11,875 youths from the Adolescent Brain Cognitive Development (ABCD) Study at ages 9 to 10 years at the onset of the study. A machine learning approach based on canonical correlation analysis was used to identify latent dimensional associations of the resting-state functional connectome with multidomain behavioral assessments including cognitive functions and psychopathological measures. For the latent resting-state functional connectivity factor showing a robust behavioral association, its ability to predict psychiatric disorders was assessed using 2-year follow-up data, and its genetic association was evaluated using twin data from the same cohort.

RESULTS

A latent functional connectome pattern was identified that showed a strong and generalizable association with the multidomain behavioral assessments (5-fold cross-validation: ρ = 0.68-0.73 for the training set [n = 5096]; ρ = 0.56-0.58 for the test set [n = 1476]). This functional connectome pattern was highly heritable (h2 = 74.42%, 95% CI: 56.76%-85.42%), exhibited a dose-response relationship with the cumulative number of psychiatric disorders assessed concurrently and at 2 years post-magnetic resonance imaging scan, and predicted the transition of diagnosis across disorders over the 2-year follow-up period.

CONCLUSIONS

These findings provide preliminary evidence for a transdiagnostic connectome-based measure that underlies individual differences in the development of psychiatric disorders during early adolescence.

Fault Detection in 3D Printing: A Study on Sensor Positioning and Vibrational Patterns

This work examines the use of accelerometers to identify vibrational patterns that can effectively predict the state of a 3D printer, which could be useful for predictive maintenance. Prototypes using both a simple rectangular shape and a more complex Octopus shape were fabricated and evaluated. Fast Fourier Transform, Spectrogram, and machine learning models, such as Principal Component Analysis and Support Vector Machine, were employed for data analysis. The results indicate that vibrational signals can be used to predict the state of a 3D printer. However, the position of the accelerometers is crucial for vibration-based fault detection. Specifically, the sensor closest to the nozzle could predict the state of the 3D printer faster at a 71% greater sensitivity compared to sensors mounted on the frame and print bed. Therefore, the model presented in this study is appropriate for vibrational fault detection in 3D printers.

Association between Biomarkers of Inflammation and 10-Year Changes in Aortic Stiffness: The Multi-Ethnic Study of Atherosclerosis

Background. Chronic inflammation is associated with incident cardiovascular events. We study the association between biomarkers of inflammation and subclinical vascular dysfunction measured as proximal aortic stiffness. Methods. MRI imaging was performed in the Multi-Ethnic Study of Atherosclerosis (MESA) at baseline (2000) and at the 10-year follow-up. Aortic arch pulse wave velocity (PWV) and ascending and descending aorta distensibility (AAD, DAD) were measured in 1223 asymptomatic individuals at both exams. Linear regression was used to study the association of baseline inflammation-C-reactive protein (CRP), interleukin-6 (IL6), and fibrinogen (Fib)-with baseline and 10-year changes in aortic stiffness (PWV, AAD, DAD). Results. The mean age of the participants was 59 ± 9 years, 47.8% of them were men, 32.6% were hypertensive at baseline, and 7.6% were diabetic. At baseline and follow-up, the mean AAD values were, respectively, 1.73 × 10-3 mmHg-1 and 1.57 × 10-3 mmHg-1, the mean DAD values were 2.19 × 10-3 mmHg-1 and 1.99 × 10-3 mmHg-1, and the mean PWV values were 8.10 m/s and 8.99 m/s. At baseline, the AAD (in 10-3 mmHg-1) and DAD (in 10-3 mmHg-1) were inversely associated with CRP (in mg/L) (AAD coeff: -0.047, p-value: 0.011, DAD coeff: -0.068, p-value: <0.001) and IL6 (in pg/mL) (AAD coeff: -0.098, p-value: 0.003, DAD coeff: -0.14, p-value: <0.001) in a univariable analysis but not after adjustment for demographic variables or cardiovascular risk factors. The baseline DAD was inversely associated with Fib (in mg/dL) (coeff: -0.334, p-value: 0.001). The baseline PWV (in m/s) was positively associated with IL6 (in pg/mL) in a univariable analysis (coeff: 0.054, p-value: 0.014). In a longitudinal analysis, the 10-year changes in DAD were inversely associated with CRP, even after adjustment for demographics and risk factors (DAD coeff: -0.08, p-value 0.044). Conclusions. Higher CRP levels at baseline were independently associated with a 10-year increase in aortic stiffness, measured as decreased aortic distensibility.

Systematic Sampling of the Female Reproductive System for Molecular Characterization

As part of the National Institutes of Health Human BioMolecular Atlas Program to develop a global platform to map the 37 trillion cells in the adult human body, we are generating a comprehensive molecular characterization of the female reproductive system. Data gathered from multiple single-cell/single-nucleus and spatial molecular assays will be used to build a 3D molecular atlas. Herein, we describe our multistep protocol, beginning with an optimized organ procurement workflow that maintains functional characteristics of the uterus, ovaries, and fallopian tubes by perfusing these organs with preservation solution. We have also developed a structured tissue sampling procedure that retains information on individual-level anatomic, physiologic, and individual diversity of the female reproductive system, toward full exploration of the function and structure of female reproductive cells. © 2023 Wiley Periodicals LLC. Basic Protocol 1: Preparation and preservation of the female reproductive system (ovaries, fallopian tubes, and uterus) prior to procurement Basic Protocol 2: Removal of the female reproductive system en bloc Basic Protocol 3: Postsurgical dissection of ovaries Basic Protocol 4: Postsurgical dissection of fallopian tubes Basic Protocol 5: Postsurgical dissection of cervix Basic Protocol 6: Postsurgical dissection of uterine body Support Protocol 1: OCT-embedded tissue protocol Support Protocol 2: Tissue fixation protocol Support Protocol 3: Snap-frozen tissue protocol Basic Protocol 7: Tissue slice preparation for Visium analysis Support Protocol 4: Hematoxylin and eosin staining for 10X Visium imaging Basic Protocol 8: Manual tissue dissociation for Multiome analysis Basic Protocol 9: Tissue dissociation for Multiome analysis using S2 Singulator.

Substrate and phosphorylation site selection by phosphoprotein phosphatases

Dynamic protein phosphorylation and dephosphorylation are essential regulatory mechanisms that ensure proper cellular signaling and biological functions. Deregulation of either reaction has been implicated in several human diseases. Here, we focus on the mechanisms that govern the specificity of the dephosphorylation reaction. Most cellular serine/threonine dephosphorylation is catalyzed by 13 highly conserved phosphoprotein phosphatase (PPP) catalytic subunits, which form hundreds of holoenzymes by binding to regulatory and scaffolding subunits. PPP holoenzymes recognize phosphorylation site consensus motifs and interact with short linear motifs (SLiMs) or structural elements distal to the phosphorylation site. We review recent advances in understanding the mechanisms of PPP site-specific dephosphorylation preference and substrate recruitment and highlight examples of their interplay in the regulation of cell division.

Coastal landscape classification using convolutional neural network and remote sensing data in Vietnam

The length of global coastline is about 356 thousand kilometers with various dynamic natural and anthropogenic. Although the number of studies on coastal landscape categorization has been increasing, it is still difficult to distinguish precisely them because the used methods commonly are traditional qualitative ones. With the leverage of remote sensing data and GIS tools, it helps categorize and identify a variety of features on land and water based on multi-source data. The aim of study is using different natural - social profile data obtained from ALOS, NOAA, and multi-temporal Landsat satellite images as input data of the convolutional-neural-network (CvNet) models for coastal landscape classification. Studies used 900 cut-line samples which represent coastal landscapes in Vietnam for training and optimizing CvNet models. As a result, nine coastal landscapes were identified including: deltas, alluvial, mature and young sand dunes, cliff, lagoon, tectonic, karst, and transitional landscapes. Three CvNet models using three different optimizer types classified the landscapes of other 1150 cut-lines in Vietnam with the accuracies about 98% and low loss function value. Excepting dalmatian, karst and delta coastal landscapes, five others distribute heterogeneous along the coasts in Vietnam. Therefore, the evaluation of additional natural components is necessary and CvNet model have ability to update new landscape types in variety of tropical nation as a step toward coastal landscape classification at both national and global scales.

Assessment of heterogeneity among participants in the Parkinson's Progression Markers Initiative cohort using α-synuclein seed amplification: a cross-sectional study

BACKGROUND

Emerging evidence shows that α-synuclein seed amplification assays (SAAs) have the potential to differentiate people with Parkinson's disease from healthy controls. We used the well characterised, multicentre Parkinson's Progression Markers Initiative (PPMI) cohort to further assess the diagnostic performance of the α-synuclein SAA and to examine whether the assay identifies heterogeneity among patients and enables the early identification of at-risk groups.

METHODS

This cross-sectional analysis is based on assessments done at enrolment for PPMI participants (including people with sporadic Parkinson's disease from LRRK2 and GBA variants, healthy controls, prodromal individuals with either rapid eye movement sleep behaviour disorder (RBD) or hyposmia, and non-manifesting carriers of LRRK2 and GBA variants) from 33 participating academic neurology outpatient practices worldwide (in Austria, Canada, France, Germany, Greece, Israel, Italy, the Netherlands, Norway, Spain, the UK, and the USA). α-synuclein SAA analysis of CSF was performed using previously described methods. We assessed the sensitivity and specificity of the α-synuclein SAA in participants with Parkinson's disease and healthy controls, including subgroups based on genetic and clinical features. We established the frequency of positive α-synuclein SAA results in prodromal participants (RBD and hyposmia) and non-manifesting carriers of genetic variants associated with Parkinson's disease, and compared α-synuclein SAA to clinical measures and other biomarkers. We used odds ratio estimates with 95% CIs to measure the association between α-synuclein SAA status and categorical measures, and two-sample 95% CIs from the resampling method to assess differences in medians between α-synuclein SAA positive and negative participants for continuous measures. A linear regression model was used to control for potential confounders such as age and sex.

FINDINGS

This analysis included 1123 participants who were enrolled between July 7, 2010, and July 4, 2019. Of these, 545 had Parkinson's disease, 163 were healthy controls, 54 were participants with scans without evidence of dopaminergic deficit, 51 were prodromal participants, and 310 were non-manifesting carriers. Sensitivity for Parkinson's disease was 87·7% (95% CI 84·9-90·5), and specificity for healthy controls was 96·3% (93·4-99·2). The sensitivity of the α-synuclein SAA in sporadic Parkinson's disease with the typical olfactory deficit was 98·6% (96·4-99·4). The proportion of positive α-synuclein SAA was lower than this figure in subgroups including LRRK2 Parkinson's disease (67·5% [59·2-75·8]) and participants with sporadic Parkinson's disease without olfactory deficit (78·3% [69·8-86·7]). Participants with LRRK2 variant and normal olfaction had an even lower α-synuclein SAA positivity rate (34·7% [21·4-48·0]). Among prodromal and at-risk groups, 44 (86%) of 51 of participants with RBD or hyposmia had positive α-synuclein SAA (16 of 18 with hyposmia, and 28 of 33 with RBD). 25 (8%) of 310 non-manifesting carriers (14 of 159 [9%] LRRK2 and 11 of 151 [7%] GBA) were positive.

INTERPRETATION

This study represents the largest analysis so far of the α-synuclein SAA for the biochemical diagnosis of Parkinson's disease. Our results show that the assay classifies people with Parkinson's disease with high sensitivity and specificity, provides information about molecular heterogeneity, and detects prodromal individuals before diagnosis. These findings suggest a crucial role for the α-synuclein SAA in therapeutic development, both to identify pathologically defined subgroups of people with Parkinson's disease and to establish biomarker-defined at-risk cohorts.

FUNDING

PPMI is funded by the Michael J Fox Foundation for Parkinson's Research and funding partners, including: Abbvie, AcureX, Aligning Science Across Parkinson's, Amathus Therapeutics, Avid Radiopharmaceuticals, Bial Biotech, Biohaven, Biogen, BioLegend, Bristol-Myers Squibb, Calico Labs, Celgene, Cerevel, Coave, DaCapo Brainscience, 4D Pharma, Denali, Edmond J Safra Foundation, Eli Lilly, GE Healthcare, Genentech, GlaxoSmithKline, Golub Capital, Insitro, Janssen Neuroscience, Lundbeck, Merck, Meso Scale Discovery, Neurocrine Biosciences, Prevail Therapeutics, Roche, Sanofi Genzyme, Servier, Takeda, Teva, UCB, VanquaBio, Verily, Voyager Therapeutics, and Yumanity.

Abstract 1561: Preclinical examination of PLK1 inhibitors for the treatment of diffuse midline gliomas

Diffuse Midline Gliomas (DMGs) are devastating and incurable pediatric brain tumours. DMGs are characterised by epigenetic aberrations in the form of histone modifications, coupled with mitotic abnormalities, which together drive a stem-like transcriptional cell state that is critically dependent on the cell cycle. Polo-like kinase 1 (PLK1) is a pivotal regulator of mitosis and cell cycle progression. To determine an effective therapeutic strategy against DMG, we characterised the anti-tumour potential of PLK1 inhibition, either alone or in combination with radiotherapy. We show that targeting PLK1 with small molecule inhibitors BI2536 and BI6727 (volasertib) reduced DMG colony formation and cell proliferation, and induced G2/M checkpoint arrest and apoptosis in vitro at physiologically achievable, clinically relevant concentrations. When combined with radiotherapy, PLK1 inhibitors acted as potent radiosensitisers with synergistic suppression of DMG survival. We further show that PLK1 inhibitors exert potent anti-tumour effects in highly aggressive orthotopic DMG models, effectively extending the median survival of tumour harbouring mice both as a single agent and enhanced in combination with radiotherapy. We further demonstrate a potential novel role for PLK1 in defining an oncogenic transcriptional state in DMG by acting as a conduit between cell cycle progression and the DMG epigenome through modulation of polycomb repressive complex 2 (PRC2) activity and its resultant histone methyltransferase function. Together, these data indicate that targeting PLK1 is a highly promising therapeutic strategy to arrest DMG tumorgenicity. This data has formed the basis for a planned international Phase 1/2 trial of the PLK1 inhibitor volasertib in combination with radiotherapy in paediatric patients with DMG.

Citation Format: Elisha Hayden, Laura Franshaw, Dannielle Upton, Jie Liu, Hieu Nguyen, Swapna Joshi, Maria Tsoli, Emmy Dolman, Benjamin Rayner, David Ziegler. Preclinical examination of PLK1 inhibitors for the treatment of diffuse midline gliomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1561.

Catchment sourcing urban pesticide pollution using constructed wetlands in Melbourne, Australia

A survey of 111 urban constructed stormwater wetlands (median watershed area = 86.8 ha) was conducted to identify the major pesticides present and to determine their major catchment sources (residential, industrial, commercial, sporting ovals) and associations with catchment imperviousness. Melbourne, Australia, has separate stormwater and sewerage systems and these wetlands are designed to treat urban stormwater. To maximise the pesticides that could be detected, three types of passive samplers (POCIS, Chemcatcher® SDB-XC and Chemcatcher® C18) were deployed, along with collection of fine sediments. A total of 231 pesticides were screened using these methods. Pesticides that were detected in >5 % of wetlands were checked to determine their registered use in urban areas using an Australian government database (PubCris). Twenty-five pesticides were detected in >5 % of wetlands: 4 pesticides were associated with non-urban land uses (agriculture and forests), another 4 pesticides had no known registered use in urban areas and 17 were associated with urban areas. The pesticides associated with urban areas were the herbicides simazine, diuron, metolachlor, bromacil, propyzamide and paclobutrazol, the fungicides tebuconazole, propiconazole, metalaxyl, trifloxystrobin, iprodione and carbendazim and the insecticides fipronil, bifenthrin, chlorantraniliprole, thiamethoxam and permethrin. Atrazine was also detected in 59 % of wetlands but has not been registered for urban uses in Australia since 2010. It's presence in Melbourne may be due to legacy issues or aerial transportation from rural areas where it's still widely used in crop cultivation. Generally, the major urban catchment source of pesticides is from residential areas (particularly fipronil and simazine), most likely in wood preservatives, paints and from weed or insect control. Many of these widely used pesticides were correlated with increased catchment imperviousness. Some pesticides (bromacil and imidacloprid) were correlated with commercial premises and chlorantraniliprole was correlated with the presence of sporting ovals in the catchment. No pesticides were specifically correlated with industrial areas. The use of passive samplers and fine sediments, in conjunction with detailed land use mapping of stormwater wetland catchments is very effective and efficient in monitoring and sourcing pesticide contamination in urban environments.

A261 SEVERE ACUTE LIVER INJURY SECONDARY TO WILSON’S DISEASE: A CASE REPORT AND REVIEW OF THE LITERATURE

Background

Wilson’s disease is autosomal recessive and rare (prevalence 1/30000-1/50000) caused by mutations in the ATP7B gene involved in copper excretion. Copper deposition drives hepatic injury, along with neuropsychiatric-ophthalmologic, and hematologic symptoms. Leipzig criteria greater than 4 establishes the diagnosis.

Purpose

We report a case of severe liver injury secondary to probable Wilson’s disease.

Method

Literature review of diagnosis, management including emerging therapies was performed using PubMed.

Result(s)

A 29-year-old otherwise healthy male with no family history of liver disease presented with abdominal pain, jaundice, and severe acute liver injury (ALT 1534 U/L ALP 114 U/L bilirubin 113 umol/L) initially misdiagnosed as hepatitis A in community urgent care. He had worsening liver injury (ALT 1809 U/L bilirubin 411 umol/L), with normal INR and no encephalopathy over an additional 3 weeks and was admitted to our tertiary care centre for further work up. History did not reveal viral prodromes, herbals or natural remedies. CBD oil was the only potential exposure, though longstanding use of the same brand argued against this as a cause. Chronic liver disease workup was negative (viral hepatitides, SARS-CoV-2, alpha-1-antitrypsin, acetaminophen level, iron profile, and comprehensive Mitogen autoantibody panel). Patent vasculature on Doppler US. Liver biopsy showed diffuse lobular inflammation, hepatocyte necrosis, 30% parenchymal involvement, primarily lymphocytes with some eosinophils and plasma cells, and no viral inclusions suggesting acute hepatitis with drugs or viral hepatitis as etiologies. The 24-hour urine copper was elevated at 2.19 umol/d (<0.80). Biopsy copper dry weight 60mcg/g (N<50; >250 diagnostic). Normal ceruloplasmin 0.30g/L and serum copper 25.8 umol/L. MRI brain not suggestive of Wilson’s disease, no Kayser-Fleischer rings on Ophthalmology assessment, and no hemolysis. Given a Leipzig score of 3 suggesting possible Wilson’s disease he was started on penicillamine 1500mg daily. Five weeks later he had serologic (ALT 1061 U/L bilirubin 128 umol/L) improvement, yet elevated elastography at 22kPa IQR 5% likely due to inflammation. Given coverage issues, he was switched to compassionate trientine 500mg BID with further improvement (ALT 347 U/L bilirubin 26 umol/L). Sequencing for ATP7B gene mutations are pending (Blueprint Genetics).

Conclusion(s)

Wilson’s disease should be considered in those with hepatic or neuropsychiatric symptoms, transaminases in the 1000s or acute liver failure. Treatment is lifelong with typically good prognosis and is fatal if untreated. Treatment options include chelators D-penicillamine (first line, with side effects including proteinuria and worsened neurological symptoms) and trientine (fewer side effects). Zinc prevents copper absorption and can be used in asymptomatic patients. Transplant in acute liver failure and end-stage liver disease is guided by the King’s score. Several novel therapies including gene therapy are in development.

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Disclosure of Interest

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Modeling transcranial magnetic stimulation coil with magnetic cores

Objective.Accurate modeling of transcranial magnetic stimulation (TMS) coils with the magnetic core is largely an open problem since commercial (quasi) magnetostatic solvers do not output specific field characteristics (e.g. induced electric field) and have difficulties when incorporating realistic head models. Many open-source TMS softwares do not include magnetic cores into consideration. This present study reports an algorithm for modeling TMS coils with a (nonlinear) magnetic core and validates the algorithm through comparison with finite-element method simulations and experiments.Approach.The algorithm uses the boundary element fast multipole method applied to all facets of a tetrahedral core mesh for a single-state solution and the successive substitution method for nonlinear convergence of the subsequent core states. The algorithm also outputs coil inductances, with or without magnetic cores. The coil-core combination is solved only once i.e. before incorporating the head model. The resulting primary TMS electric field is proportional to the total vector potential in the quasistatic approximation; it therefore also employs the precomputed core magnetization.Main results.The solver demonstrates excellent convergence for typical TMS field strengths and for analyticalB-Happroximations of experimental magnetization curves such as Froelich's equation or an arctangent equation. Typical execution times are 1-3 min on a common multicore workstation. For a simple test case of a cylindrical core within a one-turn coil, our solver computed the small-signal inductance nearly identical to that from ANSYS Maxwell. For a multiturn rodent TMS coil with a core, the modeled inductance matched the experimental measured value to within 5%.Significance.Incorporating magnetic core in TMS coil design has advantages of field shaping and energy efficiency. Our software package can facilitate model-informed design of more efficiency TMS systems and guide selection of core material. These models can also inform dosing with existing clinical TMS systems that use magnetic cores.

Preclinical Evaluation of 89Zr-Panitumumab for Biology-Guided Radiation Therapy

PURPOSE

Biology-guided radiation therapy (BgRT) uses real-time line-of-response data from on-board positron emission tomography (PET) detectors to guide beamlet delivery during therapeutic radiation. The current workflow requires ¹⁸F-fluorodeoxyglucose (FDG) administration daily before each treatment fraction. However, there are advantages to reducing the number of tracer injections by using a PET tracer with a longer decay time. In this context, we investigated ⁸⁹Zr-panitumumab (⁸⁹Zr-Pan), an antibody PET tracer with a half-life of 78 hours that can be imaged for up to 9 days using PET.

METHODS AND MATERIALS

The BgRT workflow was evaluated preclinically in mouse colorectal cancer xenografts (HCT116) using small-animal positron emission tomography/computed tomography (PET/CT) for imaging and image-guided kilovoltage conformal irradiation for therapy. Mice (n = 5 per group) received 7 MBq of ⁸⁹Zr-Pan as a single dose 2 weeks after tumor induction, with or without fractionated radiation therapy (RT; 6 × 6.6 Gy) to the tumor region. The mice were imaged longitudinally to assess the kinetics of the tracer over 9 days. PET images were then analyzed to determine the stability of the PET signal in irradiated tumors over time.

RESULTS

Mice in the treatment group experienced complete tumor regression, whereas those in the control group were killed because of tumor burden. PET imaging of ⁸⁹Zr-Pan showed well-delineated tumors with minimal background in both groups. On day 9 postinjection, tumor uptake of ⁸⁹Zr-Pan was 7.2 ± 1.7 in the control group versus 5.2 ± 0.5 in the treatment group (mean percentage of injected dose per gram of tissue [%ID/g] ± SD; P = .07), both significantly higher than FDG uptake (1.1 ± 0.5 %ID/g) 1 hour postinjection. To assess BgRT feasibility, the clinical eligibility criteria was computed using human-equivalent uptake values that were extrapolated from preclinical PET data. Based on this semiquantitative analysis, BgRT may be feasible for 5 consecutive days after a single 740-MBq injection of ⁸⁹Zr-Pan.

CONCLUSIONS

This study indicates the potential of long-lived antibody-based PET tracers for guiding clinical BgRT.

An efficient approach to identifying anti-government sentiment on Twitter during Michigan protests

Trust in the government is an important dimension of happiness according to the World Happiness Report (Skelton, 2022). Recently, social media platforms have been exploited to erode this trust by spreading hate-filled, violent, anti-government sentiment. This trend was amplified during the COVID-19 pandemic to protest the government-imposed, unpopular public health and safety measures to curb the spread of the coronavirus. Detection and demotion of anti-government rhetoric, especially during turbulent times such as the COVID-19 pandemic, can prevent the escalation of such sentiment into social unrest, physical violence, and turmoil. This article presents a classification framework to identify anti-government sentiment on Twitter during politically motivated, anti-lockdown protests that occurred in the capital of Michigan. From the tweets collected and labeled during the pair of protests, a rich set of features was computed from both structured and unstructured data. Employing feature engineering grounded in statistical, importance, and principal components analysis, subsets of these features are selected to train popular machine learning classifiers. The classifiers can efficiently detect tweets that promote an anti-government view with around 85% accuracy. With an F1-score of 0.82, the classifiers balance precision against recall, optimizing between false positives and false negatives. The classifiers thus demonstrate the feasibility of separating anti-government content from social media dialogue in a chaotic, emotionally charged real-life situation, and open opportunities for future research.

Application of deep learning models to detect coastlines and shorelines

Identifying and monitoring coastlines and shorelines play an important role in coastal erosion assessment around the world. The application of deep learning models was used in this study to detect coastlines and shorelines in Vietnam using high-resolution satellite images and different object segmentation methods. The aims are to (1) propose indicators to identify coastlines and shorelines; (2) build deep learning (DL) models to automatically interpret coastlines and shorelines from high-resolution remote sensing images; and (3) apply DL-trained models to monitor coastal erosion in Vietnam. Eight DL models were trained based on four artificial-intelligent-network structures, including U-Net, U2-Net, U-Net3+, and DexiNed. The high-resolution images collected from Google Earth Pro software were used as input data for training all models. As a result, the U-Net using an input-image size of 512 × 512 provides the highest performance of 98% with a loss function of 0.16. The interpretation results of this model were used effectively for the coastline and shoreline identification in assessing coastal erosion in Vietnam due to sea-level rise in storm events over 20 years. The outcomes proved that while the shoreline is ideal for observing seasonal tidal changes or the immediate motions of current waves, the coastline is suitable to assess coastal erosion caused by the influence of sea-level rise during storms. This paper has provided a broad scope of how the U-Net model can be used to predict the coastal changes over vietnam and the world.

Hallucinating symmetric protein assemblies

Deep learning generative approaches provide an opportunity to broadly explore protein structure space beyond the sequences and structures of natural proteins. Here, we use deep network hallucination to generate a wide range of symmetric protein homo-oligomers given only a specification of the number of protomers and the protomer length. Crystal structures of seven designs are very similar to the computational models (median root mean square deviation: 0.6 angstroms), as are three cryo-electron microscopy structures of giant 10-nanometer rings with up to 1550 residues and C33 symmetry; all differ considerably from previously solved structures. Our results highlight the rich diversity of new protein structures that can be generated using deep learning and pave the way for the design of increasingly complex components for nanomachines and biomaterials.

Robust deep learning-based protein sequence design using ProteinMPNN

Although deep learning has revolutionized protein structure prediction, almost all experimentally characterized de novo protein designs have been generated using physically based approaches such as Rosetta. Here, we describe a deep learning-based protein sequence design method, ProteinMPNN, that has outstanding performance in both in silico and experimental tests. On native protein backbones, ProteinMPNN has a sequence recovery of 52.4% compared with 32.9% for Rosetta. The amino acid sequence at different positions can be coupled between single or multiple chains, enabling application to a wide range of current protein design challenges. We demonstrate the broad utility and high accuracy of ProteinMPNN using x-ray crystallography, cryo-electron microscopy, and functional studies by rescuing previously failed designs, which were made using Rosetta or AlphaFold, of protein monomers, cyclic homo-oligomers, tetrahedral nanoparticles, and target-binding proteins.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Sperm degradation after vasectomy follows a sperm chromatin fragmentation dependent mechanism causing DNA breaks in the toroid linker regions

Vasectomy is a widely used surgical technique creating an obstructive azoospermia. Although sperm cannot be ejaculated, the testis maintains sperm production in vasectomized males. The continuous accumulation of sperm deposited in the epididymis and the vas deferens fraction necessarily need to be degraded and eliminated. While the elimination process is carried out by granulomas that form after vasectomy, the detailed mechanisms of sperm degradation are still not known. The aim was to assess whether sperm chromatin fragmentation (SCF), a mechanism that degrades the entire sperm genome at the toroid linker regions (TLRs), is activated after vasectomy in sperm cells. We vasectomized mice and evaluated the presence of TLR-specific double-strand breaks through pulsed-field gel electrophoresis and the Comet assay at 1, 2 and 3 weeks after surgery. Results for DNA damage (Olive tail moment) at single-cell level showed an increase of double-strand breaks after vasectomy for vas deferens sperm after 1, 2 and 3 weeks postvasectomy (21.78 ± 2.29; 19.71 ± 1.79 and 32.59 ± 1.81, respectively), compared to mock surgery (7.04 ± 1.03; 10.10 ± 1.29 and 8.64 ± 0.85, respectively; P < 0.001). Similar findings were obtained for cauda epididymis sperm (P < 0.001), but not for caput epididymis (P > 0.05). Pulsed-field gel electrophoresis showed the presence of double-stranded breaks between 15 and 145 kb, indicating that DNA breaks were produced mainly in the sperm TLRs. Results presented here suggest that SCF is a mechanism activated in vas deferens after vasectomy to degrade sperm DNA when they cannot be ejaculated, preventing their function.

Stage-specific miRNAs regulate gene expression associated with growth, development and parasite-host interaction during the intra-mammalian migration of the zoonotic helminth parasite Fasciola hepatica

Background

MiRNAs are small non-coding RNAs that post-transcriptionally regulate gene expression in organisms ranging from viruses to mammals. There is great relevance in understanding how miRNAs regulate genes involved in the growth, development, and maturation of the many parasitic worms (helminths) that together afflict more than 2 billion people.

Results

Here, we describe the miRNAs expressed by each of the predominant intra-mammalian development stages of Fasciola hepatica, a foodborne flatworm that infects a wide range of mammals worldwide, most importantly humans and their livestock. A total of 124 miRNAs were profiled, 72 of which had been previously reported and three of which were conserved miRNA sequences described here for the first time. The remaining 49 miRNAs were novel sequences of which, 31 were conserved with F. gigantica and the remaining 18 were specific to F. hepatica. The newly excysted juveniles express 22 unique miRNAs while the immature liver and mature bile duct stages each express 16 unique miRNAs. We discovered several sequence variant miRNAs (IsomiRs) as well as miRNA clusters that exhibit strict temporal expression paralleling parasite development. Target analysis revealed the close association between miRNA expression and stage-specific changes in the transcriptome; for example, we identified specific miRNAs that target parasite proteases known to be essential for intestinal wall penetration (cathepsin L3). Moreover, we demonstrate that miRNAs fine-tune the expression of genes involved in the metabolic pathways that allow the parasites to move from an aerobic external environment to the anerobic environment of the host.

Conclusions

These results provide novel insight into the regulation of helminth parasite development and identifies new genes and miRNAs for therapeutic development to limit the virulence and pathogenesis caused by F. hepatica.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08644-z.

Deletion of Orc4 during oogenesis severely reduces polar body extrusion and blocks zygotic DNA replication†

Origin recognition complex subunit 4 (ORC4) is a DNA-binding protein required for DNA replication. During oocyte maturation, after the last oocyte DNA replication step and before zygotic DNA replication, the oocyte undergoes two meiotic cell divisions in which half the DNA is ejected in much smaller polar bodies. We previously demonstrated that ORC4 forms a cytoplasmic cage around the DNA that is ejected in both polar body extrusion (PBE) events. Here, we used ZP3 activated Cre to delete exon 7 of Orc4 during oogenesis to test how it affected both predicted functions of ORC4: its recently discovered role in PBE and its well-known role in DNA synthesis. Orc4 deletion severely reduced PBE. Almost half of Orc4-depleted germinal vesicle (GV) oocytes cultured in vitro were arrested before anaphase I (48%), and only 25% produced normal first polar bodies. This supports the role of ORC4 in PBE and suggests that transcription of the full-length Orc4 during oogenesis is required for efficient PBE. Orc4 deletion also abolished zygotic DNA synthesis. Fewer Orc4-depleted oocytes developed to the metaphase II (MII) stage, and after activation these oocytes were arrested at the two-cell stage without undergoing DNA synthesis. This confirms that transcription of full-length Orc4 after the primary follicle stage is required for zygotic DNA replication. The data also suggest that MII oocytes do not have a replication licensing checkpoint as cytokinesis progressed without DNA synthesis. Together, the data confirm that oocyte ORC4 is important for both PBE and zygotic DNA synthesis.

Trapped Alkali-Metal Rydberg Qubit

Rydberg interactions of trapped alkali-metal atoms are used widely to facilitate quantum gate operations in quantum processors and repeaters. In most laboratory realizations using this protocol, the Rydberg states are repelled by the trapping laser fields, requiring that the fields be turned off during gate operations. Here we create a quasi-two-level system in a regime of Rydberg excitation blockade for a mesoscopic Rb ensemble of several hundred atoms confined in a magic-wavelength optical lattice. We observe many-body Rabi oscillations between the ground and collective Rydberg state. In addition we use Ramsey interference techniques to obtain the light shifts of both the lower and upper states of the collective qubit. Whereas the coupling producing the Rabi oscillations is enhanced by a factor of sqrt[N], there is no corresponding enhancement for the light shifts. We derive an effective two-level model which is in good agreement with our observations. Trapped Rydberg qubits and an effective two-level description are expected to have broad applicability for studies of quantum simulation and networking using collective encoding in ensembles of neutral atoms.

Functional Aspects of Sperm Chromatin Organization

Sperm nuclei present a highly organized and condensed chromatin due to the interchange of histones by protamines during spermiogenesis. This high DNA condensation leads to almost inert chromatin, with the impossibility of conducting gene transcription as in most other somatic cells. The major chromosomal structure responsible for DNA condensation is the formation of protamine-DNA toroids containing 25-50 kilobases of DNA. These toroids are connected by toroid linker regions (TLR), which attach them to the nuclear matrix, as matrix attachment regions (MAR) do in somatic cells. Despite this high degree of condensation, evidence shows that sperm chromatin contains vulnerable elements that can be degraded even in fully condensed chromatin, which may correspond to chromatin regions that transfer functionality to the zygote at fertilization. This chapter covers an updated review of our model for sperm chromatin structure and its potential functional elements that affect embryo development.

Reaction Kinetics of 1,4-Cyclohexadiene with OH radicals : An Experimental and Theoretical Study

This work presents OH-initiated oxidation kinetics of 1,4-cyclochexadiene (1,4-CHD). Temperature dependence of the reaction was investigated by utilizing laser flash photolysis flow reactor and laser-induced fluorescence (LPFR/LIF) technique over the...

The Mammalian Family of Katanin Microtubule-Severing Enzymes

The katanin family of microtubule-severing enzymes is critical for cytoskeletal rearrangements that affect key cellular processes like division, migration, signaling, and homeostasis. In humans, aberrant expression, or dysfunction of the katanins, is linked to developmental, proliferative, and neurodegenerative disorders. Here, we review current knowledge on the mammalian family of katanins, including an overview of evolutionary conservation, functional domain organization, and the mechanisms that regulate katanin activity. We assess the function of katanins in dividing and non-dividing cells and how their dysregulation promotes impaired ciliary signaling and defects in developmental programs (corticogenesis, gametogenesis, and neurodevelopment) and contributes to neurodegeneration and cancer. We conclude with perspectives on future katanin research that will advance our understanding of this exciting and dynamic class of disease-associated enzymes.