Ferroptosis in renal fibrosis: a mini-review.

Ferroptosis is a novel form of programmed cell death that is iron-dependent and distinct from autophagy, apoptosis, and necroptosis. It is primarily characterised by a decrease in glutathione peroxidase 4 (GPX4) activity, or by the accumulation of lipid peroxidation and reactive oxygen species (ROS). Renal fibrosis is a common pathological change in the progression of various primary and secondary renal diseases to end-stage renal disease and poses a serious threat to human health with high morbidity and mortality. Multiple pathways contribute to the development of renal fibrosis, with ferroptosis playing a crucial role in renal fibrosis pathogenesis due to its involvement in the production of ROS. Ferroptosis is related to several signalling pathways, including System Xc-/GPX4, abnormal iron metabolism and lipid peroxidation. A number of studies have indicated that ferroptosis is closely involved in the process of renal fibrosis caused by various kidney diseases such as glomerulonephritis, renal ischaemia-reperfusion injury, diabetic nephropathy and renal calculus. Identifying the underlying molecular mechanisms that determine cell death would open up new insights to address a therapeutic strategy to renal fibrosis. The review aimed to browse and summarise the known mechanisms of ferroptosis that may be associated with biological reactions of renal fibrosis.

ABBV-319: A CD19-targeting glucocorticoid receptor modulator antibody-drug conjugate therapy for B-cell malignancies.

Glucocorticoids are key components of the current standard-of-care regimens (e.g., R-CHOP, EPOCH-R, Hyper-CVAD) for treatment of B-cell malignancy. However, systemic glucocorticoid treatment is associated with several adverse events. CD19 displays restricted expression in normal B-cells and is up-regulated in B-cell malignancies. ABBV-319 is a CD19-targeting antibody-drug conjugate (ADC) engineered to reduce glucocorticoid-associated toxicities while possessing three distinct mechanisms of action (MOA) to increase therapeutic efficacy: (1) antibody-mediated delivery of glucocorticoid receptor modulator (GRM) payload to activate apoptosis, (2) inhibition of CD19 signaling, and (3) enhanced Fc-mediated effector function via afucosylation of the antibody backbone. ABBV-319 elicited potent GRM-driven anti-tumor activity against multiple malignant B-cell lines in vitro as well as in cell line-derived xenografts (CDXs) and patient-derived xenografts (PDXs) in vivo. Remarkably, a single-dose of ABBV-319 induced sustained tumor regression and enhanced anti-tumor activity compared to repeat dosing of systemic prednisolone at the maximum tolerated dose (MTD) in mice. The unconjugated CD19 monoclonal antibody (mAb) also displayed anti-proliferative activity on a subset of B-cell lymphoma cell lines through the inhibition of PI3K signaling. Moreover, afucosylation of the CD19 mAb enhanced Fc-mediated antibody-dependent cellular cytotoxicity (ADCC), and this activity was maintained after conjugation with GRM payloads. Notably, ABBV-319 displayed superior efficacy compared to afucosylated CD19 mAb in human CD34+ PBMC-engrafted NSG-tg(Hu-IL15) transgenic mice, demonstrating enhanced anti-tumor activity when multiple MOAs are enabled. ABBV-319 also showed durable anti-tumor activity across multiple B-cell lymphoma PDX models, including non-germinal center B-cell (GCB) DLBCL and relapsed lymphoma post R-CHOP treatment. Collectively, these data support the ongoing evaluation of ABBV-319 in Phase I clinical trial (NCT05512390).

A comparative study of stereo-dependent SSVEP targets and their impact on VR-BCI performance.

Steady-state visual evoked potential brain-computer interfaces (SSVEP-BCI) have attracted significant attention due to their ease of deployment and high performance in terms of information transfer rate (ITR) and accuracy, making them a promising candidate for integration with consumer electronics devices. However, as SSVEP characteristics are directly associated with visual stimulus attributes, the influence of stereoscopic vision on SSVEP as a critical visual attribute has yet to be fully explored. Meanwhile, the promising combination of virtual reality (VR) devices and BCI applications is hampered by the significant disparity between VR environments and traditional 2D displays. This is not only due to the fact that screen-based SSVEP generally operates under static, stable conditions with simple and unvaried visual stimuli but also because conventional luminance-modulated stimuli can quickly induce visual fatigue. This study attempts to address these research gaps by designing SSVEP paradigms with stereo-related attributes and conducting a comparative analysis with the traditional 2D planar paradigm under the same VR environment. This study proposed two new paradigms: the 3D paradigm and the 3D-Blink paradigm. The 3D paradigm induces SSVEP by modulating the luminance of spherical targets, while the 3D-Blink paradigm employs modulation of the spheres' opacity instead. The results of offline 4-object selection experiments showed that the accuracy of 3D and 2D paradigm was 85.67 and 86.17% with canonical correlation analysis (CCA) and 86.17 and 91.73% with filter bank canonical correlation analysis (FBCCA), which is consistent with the reduction in the signal-to-noise ratio (SNR) of SSVEP harmonics for the 3D paradigm observed in the frequency-domain analysis. The 3D-Blink paradigm achieved 75.00% of detection accuracy and 27.02 bits/min of ITR with 0.8 seconds of stimulus time and task-related component analysis (TRCA) algorithm, demonstrating its effectiveness. These findings demonstrate that the 3D and 3D-Blink paradigms supported by VR can achieve improved user comfort and satisfactory performance, while further algorithmic optimization and feature analysis are required for the stereo-related paradigms. In conclusion, this study contributes to a deeper understanding of the impact of binocular stereoscopic vision mechanisms on SSVEP paradigms and promotes the application of SSVEP-BCI in diverse VR environments.

Dietary vitamin C and vitamin E with the risk of aortic aneurysm and dissection: A prospective population-based cohort study.

BACKGROUND AND AIMS: The associations between dietary vitamin C (VC), vitamin E (VE) intake and aortic aneurysm and dissection (AAD) remain unclear. This study aimed to prospectively investigate the associations between dietary VC and VE with the incident risk of AAD. METHODS AND RESULTS: A total of 139 477 participants of UK Biobank cohort were included in the analysis. Dietary VC and VE consumptions were acquired through a 24-h recall questionnaire. Cox proportional regression models were used to examine the associations between VC, VE intake and the risk of AAD. Incident AAD was ascertained through hospital inpatient records and death registers. During a median follow-up of 12.5 years, 962 incident AAD events were documented. Both dietary VC [adjusted hazard ratio (HR), 0.77; 95 % confidence intervals (CI), 0.63-0.93; P-trend = 0.008] and VE (adjusted HR, 0.70; 95 % CI, 0.57-0.87; P-trend = 0.002) were inversely associated with incident AAD when comparing the participants in the highest quartile with those in the lowest. In subgroup analyses, the associations were more pronounced in participants who were over 60 years old, participants with smoking history, hypertension or hyperlipidemia, who were under the high risk of AAD. CONCLUSION: Higher dietary VC and VE intakes are associated with reduced risk of AAD. Our study emphasizes the importance of diet adjustment strategies targeted on VC and VE to lower the incidence rate of AAD especially in the high-risk population.

Modified Nishida muscle transposition procedure combined with superior rectus muscle tenotomy for inferior rectus muscle aplasia.

The modified Nishida muscle transposition procedure, in which one-third of each vertical rectus muscle belly is sutured onto the sclera in the infero- and superotemporal quadrants without either tenotomy of the vertical rectus muscles or splitting of the vertical rectus muscle is an effective treatment for abducens nerve palsy. We report a case of inferior rectus muscle aplasia treated using the modified Nishida procedure to transpose both horizontal rectus muscles inferiorly combined with superior rectus tenotomy.

Effect of Listening Channels for Sport-Event Theme Songs on Willingness to Share.

Purpose: The sport-event theme songs is a crucial means to evoke consumer enthusiasm and boost the influence of sport event. This research aims to examine the effects of direct and indirect listening channels for sport-event theme songs on consumers' willingness to share. Methods: In this research, three between-subjects experiments were conducted to measure the effect of listening channels for sport-event theme songs on the willingness to share, along with the moderating effects of fans' fanaticism and sport-event type. All participants in the experiments were social populations from China. Results: Study 1 reveals that direct listening is more likely to cause consumers to share cognitive information about sport-event theme songs; indirect listening, meanwhile, makes them more willing to share the emotional value of the songs. Study 2 indicates that fans' fanaticism moderates the relationship between listening type and shared content. In the case of low fanaticism, indirect listening can increase consumers' willingness to share sport-event theme songs compared with direct listening. Study 3 reveals that sport-event type moderates the relationship between listening type and shared content. For public welfare sport events, indirect listening is more likely than direct listening to cause consumers to share the emotional value of sport-event theme songs. For commercial events, compared with indirect listening, direct listening is more likely to cause consumers to share cognitive information about sport-event theme songs. Conclusion: The results of this research unveiled the effect of listening channels for sport-event theme songs on the willingness to share, as well as the theoretical mechanisms behind them. In addition, this research enriches the research on listening channels in the field of psychology and provides an important basis for improving the effectiveness of sport-event theme songs.

In-stent Restenosis After Stenting for Superior Mesenteric Artery Dissection Is Associated With Stent Landing Zone: From Clinical Prediction to Hemodynamic Mechanisms.

OBJECTIVE: To identify risk factors for in-stent restenosis (ISR) in patients undergoing stent placement for superior mesenteric artery dissection (SMAD) and to determine the hemodynamic mechanism underlying ISR. METHODS: For this retrospective study, patients with SMAD who had ISR after stent placement were included in the ISR group, and age- and sex-matched patients with SMAD who did not experience ISR after stent placement were included in the control group. Clinical, imaging, and hemodynamic data were assessed. Multivariable regression was used to identify independent ISR risk factors. Structural and fluid dynamics simulations were applied to determine the hemodynamic mechanism underlying the occurrence of ISR. RESULTS: The study population included 26 patients with ISR and 26 control patients. Multivariate analysis demonstrated that stent-to-vascular (S/V) ratio (odds ratio [OR], 1.14; 95% confidence interval [CI]: 1.00-1.29; p=0.045), stent proximal position >10 mm away from the SMA root (OR, 108.67; 95% CI: 3.09-3816.42; p=0.010), and high oscillatory shear index (OSI) area (OR, 1.25; 95% CI: 1.02-1.52; p=0.029) were predictors of ISR. In structural and fluid dynamics simulations, a stent proximal position near the abdominal aorta (AA) or entering into the AA reduced the contact area between the proximal struts of the stent and the vascular wall, and alleviated the distal lumen overdilation. CONCLUSION: The S/V ratio, stent proximal position away from the SMA root (>10 mm), and high OSI area are independent risk factors for ISR in patients with SMAD undergoing stent placement. Deploying the proximal end of the stent near the AA or entering into the AA appears to improve the hemodynamic environment in the SMA lumen and ultimately reduce the risk of ISR. CLINICAL IMPACT: In-stent restenosis is an uncommon but potentially catastrophic complication after stent placement for the management of superior mesenteric artery dissection. This study identified risk factors for in-stent restenosis and demonstrated that, as long as the stent can fully cover the dissection range, deploying the proximal end of the stent near the abdominal aorta or less entering into the abdominal aorta may reduce the risk of in-stent restenosis in this patient population.

piRNAs as emerging biomarkers and physiological regulatory molecules in cardiovascular disease.

Cardiovascular diseases (CVD) represent one of the most considerable global health threats, owing to their high incidence and mortality rates. Despite the ongoing advancements in detection, prevention, treatment, and prognosis of CVD, which have resulted in a decline in both incidence and mortality rates, CVD remains a major public health concern. Therefore, novel diagnostic biomarkers and therapeutic interventions are imperative to minimise the risk of CVD. Non-coding RNAs (ncRNAs) have recently gained increasing attention, with PIWI-interacting RNAs (piRNAs) emerging as a class of small ncRNAs traditionally recognised for their role in silencing transposons within cells. Although the functional roles of PIWI proteins and piRNAs in human cells remain unclear, growing evidence suggests that these molecules are gradually becoming valuable biomarkers for the diagnosis and treatment of CVD. This review provides a comprehensive summary of the latest studies on piRNAs in CVD. This review discusses the roles of piRNAs in various cardiovascular subtypes, including myocardial hypertrophy, heart failure, myocardial infarction, and cardiac regeneration. The perceived insights may contribute novel perspectives for the diagnosis and treatment of CVD.

Effects of high moisture ear corn on production performance, milk fatty acid composition, serum antioxidant status, and immunity in primiparous dairy cows.

Objective: This study evaluated the effects of high moisture ear corn (HMEC) on production performance, milk fatty acid composition, serum antioxidant status, and immunity in primiparous dairy cows. Methods: A total of 45 healthy primiparous Holstein cows (36.50±4.30 kg of milk/day, 201±9.00 lactating days in milk) were sorted into 3 groups: control group (CG, n = 15), 50% HMEC (replacing 50% steam-flaked corn with HMEC, n = 15), and 100% HMEC (replacing steam-flaked corn with HMEC, n = 15) on an equal dry matter (DM) basis. The study consisted of adaptation period of 14 days, followed by a formal period of 60 days. Feed intake and milk yield were recorded daily. Milk and blood samples were collected on 1, 30, and 60 d of the experimental period. Results: The 50% HMEC group and 100% HMEC group significantly increased (p<0.05) milk yield and dry matter intake (DMI) in dairy cows compared to the control group (CG). The 100% HMEC group showed an increase (p<0.05) in 4% fat-corrected milk (4% FCM). Both the 50% HMEC group and 100% HMEC group exhibited significant decreases (p<0.05) in the content of C10:0, C12:0, and C14:0 fatty acids, along with a significant increase (p<0.05) in cis-9C18:1 content. The saturated fatty acid (SFA) content was significantly lower (p<0.05) in the 50% HMEC and 100% HMEC groups than that of CG. Conversely, the monounsaturated fatty acid (MUFA) content was higher (p<0.05) in the 50% HMEC and 100% HMEC groups than that in CG. Notably, the 100% HMEC group significantly increased (p<0.05) the serum superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) content, while also decreasing the serum malondialdehyde (MDA) content (p<0.05). Moreover, the 100% HMEC group significantly increased (p<0.05) the content of immunoglobulin G (IgG) and immunoglobulin M (IgM). Conclusion: High moisture ear corn could improve production performance and milk fatty acid levels and enhance immunity and antioxidant capacity in dairy cows. These results lay the foundation for the wider application of HMEC in ruminant animal diets.

Average Time Consumption Per Character - a Practical Performance Metric for Generic Synchronous BCI Spellers.

OBJECTIVE: The information transfer rate (ITR) is widely accepted as a performance metric for generic brain-computer interface (BCI) spellers, while it is noticeable that the communication speed given by ITR is actually an upper bound which however can never be reached in real systems. A new performance metric is therefore needed. METHODS: In this paper, a new metric named average time consumption per character (ATCPC) is proposed. It quantifies how long it takes on average to type one character using a typical synchronous BCI speller. To analytically derive ATCPC, the real typing process is modelled with a random walk on a graph. Misclassification and backspace are carefully characterized. A close-form formula of ATCPC is obtained through computing the hitting time of the random walk. The new metric is validated through simulated typing experiments and compared with ITR. RESULTS: Firstly, the formula and simulation show a good consistency. Secondly, ITR always tends to overestimate the communication speed, while ATCPC is more realistic. CONCLUSION: The proposed ATCPC metric is valid. SIGNIFICANCE: ATCPC is a qualified substitute for ITR. ATCPC also reveals the great potential of keyboard optimization to further enhance the performance of BCI spellers, which was hardly investigated before.

Machine Learning for Experimental Reactivity of a Set of Metal Clusters toward C-H Activation.

Understanding the mechanisms of C-H activation of alkanes is a very important research topic. The reactions of metal clusters with alkanes have been extensively studied to reveal the electronic features governing C-H activation, while the experimental cluster reactivity was qualitatively interpreted case by case in the literature. Herein, we prepared and mass-selected over 100 rhodium-based clusters (RhxVyOz- and RhxCoyOz-) to react with light alkanes, enabling the determination of reaction rate constants spanning six orders of magnitude. A satisfactory model being able to quantitatively describe the rate data in terms of multiple cluster electronic features (average electron occupancy of valence s orbitals, the minimum natural charge on the metal atom, cluster polarizability, and energy gap involved in the agostic interaction) has been constructed through a machine learning approach. This study demonstrates that the general mechanisms governing the very important process of C-H activation by diverse metal centers can be discovered by interpreting experimental data with artificial intelligence.

Photoreversible Aggregation of the Biliprotein Containing the First and Second GAF Domains of a Cyanobacteriochrome All2699 in Nostoc sp. PCC7120.

As plant photoreceptors, phytochromes are capable of detecting red light and far-red light, thereby governing plant growth. All2699 is a photoreceptor found in Nostoc sp. PCC7120 that specifically responds to red light and far-red light. All2699g1g2 is a truncated protein carrying the first and second GAF (cGMP phosphodiesterase/adenylyl cyclase/FhlA) domains of All2699. In this study, we found that, upon exposure to red light, the protein underwent aggregation, resulting in the formation of protein aggregates. Conversely, under far-red light irradiation, these protein aggregates dissociated. We delved into the factors that impact the aggregation of All2699g1g2, focusing on the protein structure. Our findings showed that the GAF2 domain contains a low-complexity (LC) loop region, which plays a crucial role in mediating protein aggregation. Specifically, phenylalanine at position 239 within the LC loop region was identified as a key site for the aggregation process. Furthermore, our research revealed that various factors, including irradiation time, temperature, concentration, NaCl concentration, and pH value, can impact the aggregation of All2699g1g2. The aggregation led to variations in Pfr concentration depending on temperature, NaCl concentration, and pH value. In contrast, ΔLC did not aggregate and therefore lacked responses to these factors. Consequently, the LC loop region of All2699g1g2 extended and enhanced sensory properties.

A Subject-Specific Attention Index Based on the Weighted Spectral Power.

As an essential cognitive function, attention has been widely studied and various indices based on EEG have been proposed for its convenience and easy availability for real-time attention monitoring. Although existing indices based on spectral power of empirical frequency bands are able to describe the attentional state in some way, the reliability still needs to be improved. This paper proposed a subject-specific attention index based on the weighted spectral power. Unlike traditional indices, the ranges of frequency bands are not empirical but obtained from subject-specific change patterns of spectral power of electroencephalograph (EEG) to overcome the great inter-subject variance. In addition, the contribution of each frequency component in the frequency band is considered different. Specifically, the ratio of power spectral density (PSD) function in attentional and inattentional state is utilized to calculate the weight to enhance the effectiveness of the proposed index. The proposed subject-specific attention index based on the weighted spectral power is evaluated on two open datasets including EEG data of a total of 44 subjects. The results of the proposed index are compared with 3 traditional attention indices using various statistical analysis methods including significance tests and distribution variance measurements. According to the experimental results, the proposed index can describe the attentional state more accurately. The proposed index respectively achieves accuracies of 86.21% and 70.00% at the 1% significance level in both the t-test and Wilcoxon rank-sum test for two datasets, which obtains improvements of 41.38% and 20.00% compared to the best result of the traditional indices. These results indicate that the proposed index provides an efficient way to measure attentional state.

Deciphering dynamic interactions between spermatozoa and the ovarian microenvironment through integrated multi-omics approaches in viviparous Sebastes schlegelii.

The ovarian microenvironment plays a crucial role in ensuring the reproductive success of viviparous teleosts. However, the molecular mechanism underlying the interaction between spermatozoa and the ovarian microenvironment has remained elusive. This study aimed to contribute to a better understanding of this process in black rockfish (Sebastes schlegelii) using integrated multi-omics approaches. The results demonstrated significant upregulation of ovarian complement-related proteins and pattern recognition receptors, along with remodeling of glycans on the surface of spermatozoa at the early spermatozoa-storage stage (1 month after mating). As spermatozoa were stored over time, ovarian complement proteins were progressively repressed by tryptophan and hippurate, indicating a remarkable adaptation of spermatozoa to the ovarian microenvironment. Before fertilization, a notable upregulation of cellular junction proteins was observed. The study revealed that spermatozoa bind to ZPB2a protein through GSTM3 and that ZPB2a promotes spermatozoa survival and movement in a GSTM3-dependent manner. These findings shed light on a key mechanism that influences the dynamics of spermatozoa in the female reproductive tract, providing valuable insights into the molecular networks regulating spermatozoa adaptation and survival in species with internal fertilization.

When inflammatory stressors dramatically change, disease phenotypes may transform between autoimmune hematopoietic failure and myeloid neoplasms.

Aplastic anemia (AA) and hypoplastic myelodysplastic syndrome are paradigms of autoimmune hematopoietic failure (AHF). Myelodysplastic syndrome and acute myeloid leukemia are unequivocal myeloid neoplasms (MNs). Currently, AA is also known to be a clonal hematological disease. Genetic aberrations typically observed in MNs are detected in approximately one-third of AA patients. In AA patients harboring MN-related genetic aberrations, a poor response to immunosuppressive therapy (IST) and an increased risk of transformation to MNs occurring either naturally or after IST are predicted. Approximately 10%-15% of patients with severe AA transform the disease phenotype to MNs following IST, and in some patients, leukemic transformation emerges during or shortly after IST. Phenotypic transformations between AHF and MNs can occur reciprocally. A fraction of advanced MN patients experience an aplastic crisis during which leukemic blasts are repressed. The switch that shapes the disease phenotype is a change in the strength of extramedullary inflammation. Both AHF and MNs have an immune-active bone marrow (BM) environment (BME). In AHF patients, an inflamed BME can be evoked by infiltrated immune cells targeting neoplastic molecules, which contributes to the BM-specific autoimmune impairment. Autoimmune responses in AHF may represent an antileukemic mechanism, and inflammatory stressors strengthen antileukemic immunity, at least in a significant proportion of patients who have MN-related genetic aberrations. During active inflammatory episodes, normal and leukemic hematopoieses are suppressed, which leads to the occurrence of aplastic cytopenia and leukemic cell regression. The successful treatment of underlying infections mitigates inflammatory stress-related antileukemic activities and promotes the penetration of leukemic hematopoiesis. The effect of IST is similar to that of treating underlying infections. Investigating inflammatory stress-powered antileukemic immunity is highly important in theoretical studies and clinical practice, especially given the wide application of immune-activating agents and immune checkpoint inhibitors in the treatment of hematological neoplasms.

Sustainable tourism development for traditional Chinese drama's intangible cultural heritage.

This study establishes an expert-driven evaluation system to assess the sustainable tourism development of drama-related intangible cultural heritage in China. Utilizing the Saaty 1-9 scale and hierarchical analysis method, 52 experts determined indicator weights and current development levels. Four dimensions are evaluated: humanistic value, project quality, tourism development, and sustainability. Results reveal humanistic value as most vital at 41.70 % weight. Secondary factors are project quality (29.89 %), tourism development (20.87 %), and sustainability (7.54 %). Aesthetic value, dissemination degree, and location conditions proved to the crucial tourism indicators. The ideological value of drama is paramount, alongside visibility and climate factors. The evaluation demonstrated strong preservation of humanistic value but deficiencies in tourism development, especially regarding infrastructure. Key recommendations include balancing preservation, dissemination, and innovation; emphasizing ideological value, visibility, and climate suitability; maintaining humanistic diversity; and improving site infrastructure. Further testing of evaluation indicators across periods is warranted alongside examining green revitalization potential. This assessment, guided by experts, offers a thorough framework for the sustainable development and preservation of the precious intangible heritage embodied in Chinese drama.

Unraveling Pre-filled Syringe Needle Clogging: Exploring a Fresh Outlook Through Innovative Techniques.

OBJECTIVE: This study aimed to investigate the movement of liquid in the needle region of staked-in-needle pre-filled syringes using neutron imaging and synchrotron X-ray tomography. The objective was to gain insights into the dynamics of liquid presence and understand the factors contributing to needle clogging. METHODS: Staked-in-needle pre-filled syringes were examined using neutron radiography and synchrotron X-ray phase-contrast computed tomography. Neutron radiography provided a 2D visualization of liquid presence in the needle, while synchrotron X-ray tomography offered high-resolution 3D imaging to study detailed morphological features of the liquid. RESULTS: Neutron radiography revealed liquid presence in the needle region for as-received samples and after temperature and pressure cycling. Pressure cycling had a more pronounced effect on liquid formation. Synchrotron X-ray tomography confirmed the presence of liquid and revealed various morphologies, including droplets of different sizes, liquid segments blocking sections of the needle, and a thin layer covering the needle wall. Liquid presence was also observed between the steel needle and the glass barrel. CONCLUSIONS: The combination of neutron imaging and synchrotron X-ray tomography provided valuable insights into the dynamics of liquid movement in staked-in-needle pre-filled syringes. Temperature and pressure cycling were found to contribute to additional liquid formation, with pressure changes playing a significant role. The detailed morphological analysis enhanced the understanding of microstructural arrangements within the needle. This research contributes to addressing the issue of needle clogging and can guide the development of strategies to improve pre-filled syringe performance.

Contributions of Chinese hamster ovary cell derived extracellular vesicles and other cellular materials to hollow fiber filter fouling during perfusion manufacturing of monoclonal antibodies.

Hollow fiber filter fouling is a common issue plaguing perfusion production process for biologics therapeutics, but the nature of filter foulant has been elusive. Here we studied cell culture materials especially Chinese hamster ovary (CHO) cell-derived extracellular vesicles in perfusion process to determine their role in filter fouling. We found that the decrease of CHO-derived small extracellular vesicles (sEVs) with 50-200 nm in diameter in perfusion permeates always preceded the increase in transmembrane pressure (TMP) and subsequent decrease in product sieving, suggesting that sEVs might have been retained inside filters and contributed to filter fouling. Using scanning electron microscopy and helium ion microscopy, we found sEV-like structures in pores and on foulant patches of hollow fiber tangential flow filtration filter (HF-TFF) membranes. We also observed that the Day 28 TMP of perfusion culture correlated positively with the percentage of foulant patch areas. In addition, energy dispersive X-ray spectroscopy-based elemental mapping microscopy and spectroscopy analysis suggests that foulant patches had enriched cellular materials but not antifoam. Fluorescent staining results further indicate that these cellular materials could be DNA, proteins, and even adherent CHO cells. Lastly, in a small-scale HF-TFF model, addition of CHO-specific sEVs in CHO culture simulated filter fouling behaviors in a concentration-dependent manner. Based on these results, we proposed a mechanism of HF-TFF fouling, in which filter pore constriction by CHO sEVs is followed by cake formation of cellular materials on filter membrane.

Generating Potential RET-Specific Inhibitors Using a Novel LSTM Encoder-Decoder Model.

The receptor tyrosine kinase RET (rearranged during transfection) plays a vital role in various cell signaling pathways and is a critical factor in the development of the nervous system. Abnormal activation of the RET kinase can lead to several cancers, including thyroid cancer and non-small-cell lung cancer. However, most RET kinase inhibitors are multi-kinase inhibitors. Therefore, the development of an effective RET-specific inhibitor continues to present a significant challenge. To address this issue, we built a molecular generation model based on fragment-based drug design (FBDD) and a long short-term memory (LSTM) encoder-decoder structure to generate receptor-specific molecules with novel scaffolds. Remarkably, our model was trained with a molecular assembly accuracy of 98.4%. Leveraging the pre-trained model, we rapidly generated a RET-specific-candidate active-molecule library by transfer learning. Virtual screening based on our molecular generation model was performed, combined with molecular dynamics simulation and binding energy calculation, to discover specific RET inhibitors, and five novel molecules were selected. Further analyses indicated that two of these molecules have good binding affinities and synthesizability, exhibiting high selectivity. Overall, this investigation demonstrates the capacity of our model to generate novel receptor-specific molecules and provides a rapid method to discover potential drugs.