Persistent Signaling Research Articles

P1314 Multi-omics analysis of Crohn’s Disease trajectory from active to remission reveals that the altered ileal anti-bacterial epithelial signals and pathogenic microbial composition and metabolomics persist despite normalizing ileal immune signals during remission

Abstract Background Characterizing gut factors that improve or persist during Crohn’s disease (CD) trajectory from active to remission to healthy-normal states is crucial for defining treatment targets and CD cure. Methods Using multi-omics (ileal transcriptomics, microbiome, and metabolomics), we aimed to compare active, mostly treatment naïve newly diagnosed CD to patients in remission, using controls as a reference Results 193 subjects were included (median age 32 years, 60% male); 78 CD in remission, 38 active and mostly (80%) treatment naïve newly diagnosed CD patients, and 77 non-IBD controls (Table 1). Controls and CD remission groups had significantly lower and mostly normal CRP, with significantly lower fecal calprotectin in the remission than in the active group (Table 1). Most patients (79%) in remission were on biologics (58% on anti-TNF and 21% on vedolizumab/Stelara). Ileal transcriptomics (Fig. 1A-B) highlighted a significant reduction of genes and pathways related to adaptive T cell activation in treated patients in remission compared to active treatment naïve patients. This decrease was significantly lower than in controls, suggesting some immune compromise likely secondary to CD therapy. There were no differences between the levels of S1008/9 genes encoding for fecal calprotectin and OSM and TREM1 genes related to the anti-TNF response in patients in remission on treatment, compared to controls. Despite that, patients in remission still showed persistent signals of elevated expression of epithelial antimicrobial pathways and genes, including DUOX2, CEACAM5/6, REG4, and DMBT1, and more novel increased goblet cells and mucin glycosylated genes and signals (Fig. 1A-B). Interestingly, these epithelial antimicrobial signals during remission were coupled with persistent pathogenic gut microbial composition, as indicated by several microbial measurements, including the published Gevers et al index (PMID:24629344), our general health and specific IBD indexes (PMID:35197084), and alpha diversity (Fig. 1C), with significant enrichment of oral bacteria that dislocated to the gut in the CD groups. Similarly, 39 of 43 (91%) of the gut metabolites (Fig. 1D) that were significantly different between CD in remission vs. controls showed similar altered directionally in active treatment naïve CD patients vs. controls, suggesting persistent metabolic alterations during remission Conclusion Multi-omics analysis shows that despite normalizing ileal immune signals and genes encoding calprotectin during remission, the altered anti-bacterial epithelial signal and pathogenic microbiome and metabolome signatures persist. This highlights the need to directly target the epithelia-microbes axis, in addition to immune suppression, to improve CD outcomes.

Characterizing immune biomarkers and effector CD8+ T-cell exhaustion in pancreatic adenocarcinoma via single-cell RNA sequencing profiling

Aim: Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer-related mortality and is characterized by T-cell exhaustion, particularly in effector CD8+ T-cells. This exhaustion, driven by persistent immunosuppressive signals in the tumor microenvironment, impairs immune function and hinders effective immunotherapy. This study aimed to identify key exhaustion-related marker genes in CD8+ T-cells linked to PDAC and assess the potential of repurposing anti-inflammatory drugs to counteract T-cell exhaustion and enhance immune responses against PDAC. Methods: We employed a multi-omics approach, integrating single-cell RNA sequencing data with whole genome sequencing to identify dysregulated exhaustion-related immune markers in CD8+ T-cells in PDAC. We examined gene expression profiles and conducted functional enrichment analysis to evaluate their roles in immune exhaustion. We analyzed mutations in the shortlisted biomarkers from The Cancer Genome Atlas (TCGA) and performed in silico mutational analysis using Maestro to evaluate the impact of an IL7R mutation (K110N) on protein function. Virtual screening using a deep learning framework, GNINA, explored the inhibitory features of the anti-inflammatory drugs oxaprozin and celecoxib on IL7R. Results: Key dysregulated exhaustion-related immune markers were identified including PRF1, GZMA, CD8A, CD3D, NKG7, IL7R, and IL2RG. Pathway enrichment analysis indicated significant involvement in T-cell receptor signaling, Th1 and Th2 differentiation, and Th17 differentiation pathways, correlating with reported poor survival outcomes in PDAC patients. Mutational analysis of IL7R revealed a likely pathogenic mutation (K110N) located in the IL-7Ralpha fibronectin type III domain. Drug repurposing of oxaprozin and celecoxib showed favorable binding interactions with both wild and mutant IL7R proteins. Conclusions: The K110N mutation, despite not causing significant structural changes, may impact T-cell and B-cell homeostasis and development. Our findings suggest that oxaprozin and celecoxib could effectively inhibit T-cell exhaustion through favorable interactions with IL7R. Further clinical studies are necessary to validate the therapeutic potential of these anti-inflammatory drugs in enhancing immune responses in pancreatic cancer.

Time to Castration Resistance is Associated With Overall Survival Even After the Achievement of Castration Resistance in Metastatic Prostate Cancer.

Recent clinical trials have shown that patients with metastatic castration-sensitive prostate cancer in real-world settings have different overall survival (OS) rates after stratifying for tumor burden or visceral metastasis. However, some patients with a low tumor burden and without visceral metastasis still have a poor survival. Androgen receptor signaling is still a main therapeutic target of prostate cancer treatment even after the achievement of castration resistance. In this regard, we hypothesized that time to castration resistance can be a prognostic factor of metastatic castration-sensitive prostate cancer even after achieving castration resistance. The current study aimed to assess the novel prognostic factors, particularly time to castration resistance, of prostate cancer in patients at a real-world single institution. The data of 261 patients who were newly diagnosed with metastatic castration-sensitive prostate cancer from January 2007 to December 2023 were retrospectively analyzed. The median OS was 60.7 months, and the median time to castration resistance was 13.1 months. Among 261 patients, 158 developed castration-resistant prostate cancer. A shorter time to castration resistance, the presence of distant lymph node metastasis, ISUP grade group 5, and older age were associated with a shorter OS in patients who developed castration-resistant prostate cancer. A shorter time to castration resistance was significantly associated with a shorter OS regardless of the tumor burden. Further, it was associated with a shorter OS even after the achievement of castration resistance. The study results support the presence of persistent androgen receptor signaling even after achieving castration resistance in prostate cancer, and time to castration resistance can be a biomarker for the activation of androgen receptor signaling regardless of tumor burden.

Fructose-Driven glycolysis supports synaptic function in subterranean rodent - Gansu Zokor (Eospalax cansus).

Several studies indicate that fructose can be used as an energy source for subterranean rodents. However, how subterranean rodents utilize fructose metabolism with no apparent physiological drawbacks remains poorly understood. In the present study, we measured field excitatory postsynaptic potentials (fEPSPs) in hippocampal slices from Gansu zokor and SD rats hippocampi before and 60 min after replacement of 10 mM glucose in the artificial cerebrospinal fluid (ACSF) with 10 mM fructose (gassed with 95 % O2 and 5 % CO2). Subsequently, we performed transcriptome analysis on Gansu zokor brains incubated with ACSF containing 10 mM fructose and determined the contents of fructose, lactate, ATP, and UA. Whole brain RNA and proteins were extracted to detect the transcriptional levels of Glut5, Khk, Aldoc, and Cs and the translational levels of GLUT5, CS, NRF2, and c-FOS. The results showed that Gansu zokor brains exhibit higher levels of GLUT5 protein and Khk mRNA levels than SD rats to facilitate fructose uptake and metabolism, resulting in increased fructose, ATP, and lactate content in the brain during fructose incubation. Stable UA levels during fructose metabolism reduce the risk of oxidative stress and neuroinflammation, and activation of the Nrf2 pathway increases downstream antioxidant capacity, thereby reducing brain damage. Persistent fEPSP signaling suggests that fructose supports excitatory synaptic transmission in the CA1 region of the hippocampus of the Gansu zokor but leads to hippocampal dysfunction in SD rats. The unique insights about fructose metabolism in the brain of Gansu zokor obtained in our study will be useful for further studies on the evolution of subterranean rodents.

Return to play in professional football players following traumatic cervical spine injury: expert opinions from the National Football League spine surgeons.

There is a paucity of high-quality return-to-play (RTP) data following treatment of cervical spine injuries in contact sports. In this study, the authors gathered insights from National Football League (NFL) team spine surgeon consultants to highlight current practices in treating cervical spine injuries and report decision-making regarding RTP in professional American football players. A cross-sectional, online survey was distributed to all NFL consulting physicians specializing in the management of spine injuries. The survey covered the following five clinical vignettes of cervical spine injuries: 1) radiculopathy, 2) myelopathy, 3) unilateral facet fracture, 4) unilateral facet dislocation, and 5) neck pain with MRI showing a ligamentous STIR signal. Participants were asked about management options and criteria to clear players for RTP using a combination of multiple-choice and open-ended answers. A total of 26 physicians from 21 of 32 (66%) teams responded. Anterior surgery was most commonly recommended for cervical disc herniation causing radiculopathy or myelopathy (73% and 88%, respectively). A rigid cervical orthosis was preferred by 68% of experts for initial management of nondisplaced unilateral facet fracture, but single-level anterior fusion was preferred by 56% for a unilateral facet dislocation. Common criteria to clear players for RTP with cervical disc herniation causing radiculopathy included a normal examination (85%), radiographic fusion postoperatively (58%), and pain-free range of motion (50%). Contraindications for RTP included persistent stenosis (35%), instability (31%), multilevel fusion (27%), and persistent cord signal change (23%). Additional criteria for RTP in players with facet fractures or dislocations included radiographic evidence of fracture healing (32% and 24%, respectively) and normal flexion/extension radiographs (24% and 32%, respectively). Finally, for players with isolated ligamentous STIR signal changes, resolution of MRI findings was required by 36% of responding physicians prior to RTP. Decision-making regarding RTP after cervical spine injuries in professional football players is complex and influenced by improvement of symptoms, pain-free range of motion, and radiographic evidence of fusion or fracture healing. Respondents preferred anterior cervical discectomy and fusion for disc herniations causing cervical radiculopathy and myelopathy, rigid orthosis for unilateral facet fractures, and surgery for unilateral facet dislocations. The results of this study provide insight into how surgeons serving as consultants to professional football teams may counsel players who sustain cervical spine injuries.

Dopaminergic responses to identity prediction errors depend differently on the orbitofrontal cortex and hippocampus.

Adaptive behavior depends on the ability to predict specific events, particularly those related to rewards. Armed with such associative information, we can infer the current value of predicted rewards based on changing circumstances and desires. To support this ability, neural systems must represent both the value and identity of predicted rewards, and these representations must be updated when they change. Here we tested whether prediction error signaling of dopamine neurons depends on two areas known to represent the specifics of rewarding events, the HC and OFC. We monitored the spiking activity of dopamine neurons in rat VTA during changes in the number or flavor of expected rewards designed to induce errors in the prediction of reward value or reward identity, respectively. In control animals, dopamine neurons registered both error types, transiently increasing firing to additional drops of reward or changes in reward flavor. These canonical firing signatures of value and identity prediction errors were significantly disrupted in rats with ipsilateral neurotoxic lesions of either HC or OFC. Specifically, HC lesions caused a failure to register either type of prediction error, whereas OFC lesions caused persistent signaling of identity prediction errors and much more subtle effects on signaling of value errors. These results demonstrate that HC and OFC contribute distinct types of information to the computation of prediction errors signaled by dopaminergic neurons.

Effects of Biological and Enzymatic Ageing on the Surface Properties of Mg-modified Biochar

The excellent surface properties of Mg-modified biochar have highlighted a broad application prospect for soil heavy metal mitigation. However, the soil biotic aging process can have an impact on the physical and chemical properties of biochar as well as the heavy metal removal performance. Therefore, MgCl2-modified biochar was subjected to a six-month microbial and enzymatically aged test to explore the effects of different biotic aging processes on the physical and chemical properties. The Pb2+ adsorption performance of Mg-modified biochar that experienced different aging processes was compared using isothermal adsorption experiments. The results showed that after microbial aging, the Mg-modified biochar pyrolyzed at 700 ℃ displayed a low persistent free radical signal, with the biofilm secreted by microorganisms wrapped on the surface of the biochar, leading to the increase in the oxygen-containing functional groups on the biochar surface and the increase in the maximum adsorption capacity of Pb2+ from 55.31 mg·g-1 to 86.27 mg·g-1. In contrast, a higher free radical signal of 500 ℃ pyrolyzed biochar suggested that the free radical inhibited the growth and reproduction of microorganisms on the biochar surface, resulting in an insignificant enhancement in maximum adsorption capacity to Pb2+ compared to that with unmodified biochar. The pores of the Mg-modified biochar were severely damaged during the enzymatically aged process, resulting in a decrease in the adsorption capacity of Pb2+ to 22.18 mg·g-1, which was significantly lower than that of the unmodified biochar. Therefore, the adsorption capacity of microbially aged Mg-modified biochar is superior to that of enzymatically aged Mg-modified biochar, mainly because the oxygen-containing functional groups exhibited on the surface of the biochar covered by microorganisms come from the extracellular secretions of microorganisms, which promote the removal of Pb2+.

Study on the vibration characteristics induced by rotating stall in a centrifugal pump based on improved variational mode decomposition

Rotating stall within the centrifugal pump has been found to induce enhanced unstable flow, which subsequently exacerbates pump vibration, posing serious risks to the safe and stable operation of the pump. To investigate the rotating stall and its induced vibration characteristics, numerical simulations have been employed to study the flow field of the rotating stall within the pump. Additionally, experimental measurements of the pump vibration signals under rotating stall conditions have been conducted, establishing the relationship between the internal rotating stall and external pump vibrations. The results have demonstrated that the reduction in flow rate promotes the development of rotating stall, with a similar distribution pattern of stall cells within the pump. The propagation speed of the stall cells within the impeller channels was approximately 20 % of the impeller rotational speed. Under deep stall conditions, the stall cells consistently moved from the suction side to the pressure side, accompanied by vortex structures of varying scales. These vortices extended to the pressure-side outlet, forming reverse vortices that blocked the impeller channels. Reconstructed external pump vibration signals, analyzed using the generalized S-transform, revealed persistent strong vibration signals in the 6 kHz–9kHz frequency range under stall conditions. Power spectral density analysis further indicated that the amplitude in the low-frequency range positively correlated with the development of rotating stall, with the primary frequency at 12 times the shaft frequency, which can be considered a characteristic frequency of stall conditions. These findings provide a scientific basis for ensuring the stable operation of centrifugal pumps.

Abstract PR010: High purity CTC RNA sequencing identifies poor prognosis lineage states in castrate resistant prostate cancer

Abstract Background: Metastatic prostate cancer is an androgen receptor (AR) driven disease for which multiple AR targeted therapies are FDA approved, leading to improvements in patient outcomes. However, development of treatment resistance remains universal, driven by AR alterations as well as lineage state transitions that bypass AR signaling and culminate in neuroendocrine prostate cancer (NEPC) with poor prognosis. Liquid biopsies could enable longitudinal molecular analysis to identify such lineage transitions, but bulk RNA sequencing of circulating tumor cells (CTCs) has been limited by the challenge of isolating sufficiently pure samples for global signaling pathway analysis. We developed a novel approach to CTC purification that results in purity comparable to tissue biopsies and performed the first large-scale CTC RNA-seq study in a multi-institutional cohort of patients with metastatic prostate cancer. Using this approach, we identified multiple prostate cancer lineage states associated with prognosis. Methods: 273 blood samples were collected from 117 patients with histologically confirmed metastatic prostate cancer treated at the University of Wisconsin Carbone Cancer Center, William S. Middleton Memorial Veterans Hospital, UC San Diego Moores Cancer Center and Dana Farber Cancer Institute. CTCs were isolated with our automated microfluidic technology integrating negative and positive selection for CTC enrichment. CTCs were captured immunomagnetically followed by RNA isolation on chip and RNA sequencing. A modification of the ESTIMATE algorithm was used to infer sample tumor purity, and CIBERSORTx was used to infer immune content. Overall survival (OS) was defined as date of death or last contact relative to first CTC sample collection. Results: 146 samples from 70 patients met our >50% purity threshold for gene expression pathway analysis. Single sample pathway analysis identified four CTC transcriptional phenotypes: luminal A (high AR signaling, intermediate proliferation), luminal B (high AR signaling, high proliferation), low proliferation, and neuroendocrine. Compared to patients with low CTC burden/low tumor purity (median OS NR, n=63), patients with luminal A (n=21) and low proliferation (n=12) phenotypes had similar survival, while patients with luminal B (n=18) and NE (n=3) had markedly shorter survival (LumB: median OS 6 months, HR 9.1, log rank p<0.0001, NE: median OS 3.7 months, HR 11.8, log rank p=0.0019). Conclusion: We report the largest CTC RNA sequencing cohort of patients with metastatic prostate cancer and demonstrate that CTC RNA-seq identifies prostate cancer lineage states mirroring those described in tissue profiling. In addition to an NE phenotype concordant with tissue histology and associated with markedly inferior overall survival, we identified a more common luminal B CTC subtype defined by persistent AR signaling and high proliferation and associated with poor prognosis comparable to NEPC. Citation Format: Marina N Sharifi, Jamie M Sperger, Amy K Taylor, Katharine E Tippins, Shannon R Reese, Viridiana Carreno, Katherine R Kaufmann, Alex H Chang, Luke A Nunamaker, Charlotte Linebarger, Kyle T Helzer, Matthew Bootsma, Grace C Blitzer, John Floberg, David Kosoff, Rana R McKay, Xiao X Wei, Shuang G Zhao, Joshua M Lang. High purity CTC RNA sequencing identifies poor prognosis lineage states in castrate resistant prostate cancer [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr PR010.

Sensitive Detection of Gynecological Cancer Recurrence Using Circulating Tumor DNA and Digital PCR: A Comparative Study with Serum Biochemical Markers.

Early detection of recurrences in gynecological cancers is crucial for women's health. Circulating tumor DNA (ctDNA) analysis through liquid biopsy offers a promising approach for monitoring disease progression and identifying relapses. This study investigated the utility of digital Polymerase Chain Reaction (dPCR) for ctDNA detection in three gynecological cancer patients with clinically confirmed relapses during a two-year post-surgical follow-up. Patient-specific tumor mutations were identified through whole-exome sequencing (WES) and confirmed via Sanger sequencing. dPCR probes targeting these mutations were used to quantify the ctDNA levels in plasma samples collected throughout the follow-up period, and the findings were compared with standard serum biochemical markers. In two patients, persistent positive dPCR signals for the selected mutations were detected after tumor removal, with ctDNA levels progressively increasing even after post-surgical chemotherapy. Notably, dPCR identified elevated ctDNA levels before an increase in the cancer antigen 125 (CA125) biochemical marker was observed. In the third patient, no ctDNA signals from the two selected mutations were detected despite clinical evidence of recurrence, suggesting the emergence of new mutations. While this study highlights the promise of dPCR for early recurrence detection in gynecological cancers, it also underscores the critical need for comprehensive mutation panels to overcome the inherent challenges posed by tumor heterogeneity and the emergence of new mutations during disease progression.

EGFR-mediated HSP70 phosphorylation facilitates PCNA association with chromatin and DNA replication.

Efficient DNA replication requires highly coordinated programs for the timely recruitment of protein complexes to DNA replication forks. Defects in this process result in replication stress, which in turn activates cell cycle checkpoints, suppresses cell proliferation and induces apoptosis. In response to persistent cell growth signals that speed up DNA replication processes, cells accelerate the recruitment of DNA replication proteins to avoid DNA replication stress. The mechanisms by which cell growth signals induce processes to facilitate the recruitment of DNA replication proteins onto the replication sites remain unclear. Here, we report that the epidermal growth factor receptor (EGFR) phosphorylates heat shock protein 70 (HSP70) for DNA replication. Such a modification promotes nuclear localization and chromatin association of HSP70, which interacts with the DNA replication coordinator, proliferating cell nuclear antigen (PCNA). HSP70 subsequently facilitates the loading of PCNA onto chromatin. Knockdown or chemical inhibition of HSP70 suppresses PCNA association with chromatin and impairs DNA synthesis and Okazaki fragment maturation, leading to replicative DNA double-strand breaks and apoptosis. Furthermore, chemical inhibition of HSP70 potentiates EGFR-tyrosine kinase inhibitor-induced tumor reduction in vivo. This work expands our understanding of oncogenesis-induced DNA replication processes and provides a foundation for improved treatments for EGFR-mutated lung cancer by simultaneously targeting HSP70.

Apoptosis signaling is activated as a transient pulse in neurons.

Apoptosis is a fundamental process of all mammalian cells but exactly how it is regulated in different primary cells remains less explored. In most contexts, apoptosis is engaged to eliminate cells. However, postmitotic cells such as neurons must efficiently balance the need for developmental apoptosis versus the physiological needs for their long-term survival. Neurons are capable of reversing the commitment to death even after the point of cytochrome c release. This ability of neurons to recover from an apoptotic signal suggests that activation of the apoptotic pathway in neurons could be much more transient than is currently recognized. Here, we investigated whether the apoptotic pathway in neurons is a persistent signal or a transient pulse in continuous presence of apoptotic stimulus. We have examined this at three key steps in apoptotic signaling: phosphorylation of c-Jun, induction of the BH3-only family proteins and Bax activation. Strikingly, we found all three of these events occur as transient signals following Nerve Growth Factor (NGF) deprivation-induced apoptosis in sympathetic neurons. This transient apoptosis signal would effectively allow neurons to reset and permit recovery if the apoptotic stimulus is reversed. Excitingly, we have also discovered that a neuron's ability to recover from an apoptotic signal is dependent on expression of the anti-apoptotic Bcl-2 family protein Bcl-xL. Bcl-xL-deficient neurons lose the ability to recover from NGF deprivation even if NGF is restored. Additionally, we show that recovery from a previous exposure to NGF deprivation is protective against subsequent deprivation. Together, these results define a novel mechanism by which apoptosis is regulated in neurons where the transient pulse of the apoptotic signaling supports neuronal resilience.

ZGSO:Cr3+,Ni2+ Persistent Phosphors with Dual Emission in NIR-I and SWIR Ranges for Bio-Imaging Applications.

Persistent luminescence (PersL) is widely used for near infrared (NIR-I, 650-950nm) imaging as they allow getting images without background. Bio-imaging in the second shortwave-infrared region SWIR-II (NIR-II, 1000-1400nm) is less widespread but is growing as it offers the advantages of low photon scattering, increased in vivo penetration depth, and improved imaging clarity. In this work, the preparation and the complete optical properties of a new material is reported, Zn1.33Ga1.33Ni0.005Cr0.005Sn0.33O3.995 (ZGSO:Cr3+, Ni2+) able of emitting in both deep-red/NIR-I and SWIR (NIR-II) and shows its potential in bioimaging. ZGSO:Cr3+, Ni2+ can be excited using different sources such as X-rays, UV, and visible light to emit persistent signals in dual biological windows (dual-BW). By integrating an energy transfer process from Cr3+ to Ni2+ within this newly synthesized material, the influence of co-dopants on signal intensity and emission wavelengths is sought to explore. PersL at ≈700nm (NIR-I) and ≈1300nm (NIR-II) have been tested in preliminary bioimaging experiments using different protocols, allowing signal detection with good spatial resolution and depth sensitivity. The dual-BW PersL imaging strategy expands the toolbox for highly accurate analysis and has, for the first time, allowed access to accurately high-resolution sensing, and tracing.

X-ray/γ-ray/Ultrasound-Activated Persistent Luminescence Phosphors for Deep Tissue Bioimaging and Therapy.

Persistent luminescence phosphors (PLPs) can remain luminescent after excitation ceases and have been widely explored in bioimaging and therapy since 2007. In bioimaging, PLPs can efficiently avoid tissue autofluorescence and light scattering interference by collecting persistent luminescence signals after the end of excitation. Outstanding signal-to-background ratios, high sensitivity, and resolution have been achieved in bioimaging with PLPs. In therapy, PLPs can continuously produce therapeutic molecules such as reactive oxygen species after removing excitation sources, which realizes sustained therapeutic activity after a single dose of light stimulation. However, most PLPs are activated by ultraviolet or visible light, which makes it difficult to reactivate the PLPs in vivo, particularly in deep tissues. In recent years, excitation sources with deep tissue penetration have been explored to activate PLPs, including X-ray, γ-ray, and ultrasound. Researchers found that various inorganic and organic PLPs can be activated by X-ray, γ-ray, and ultrasound, making these PLPs valuable in the imaging and therapy of deep-seated tumors. These X-ray/γ-ray/ultrasound-activated PLPs have not been systematically introduced in previous reviews. In this review, we summarize the recently developed inorganic and organic PLPs that can be activated by X-ray, γ-ray, and ultrasound to produce persistent luminescence. The biomedical applications of these PLPs in deep-tissue bioimaging and therapy are also discussed. This review can provide instructions for the design of PLPs with deep-tissue-renewable persistent luminescence and further promote the applications of PLPs in phototheranostics, noninvasive biosensing devices, and energy harvesting.

Persistent biogeochemical signals of land use-driven, deep root losses illuminated by C and O isotopes of soil CO2 and O2

Replacing long-lived, rarely disturbed vegetation with short-lived, frequently disturbed vegetation is a widespread phenomenon in the Anthropocene that can influence ecosystem functioning and soil development by reducing the abundance of deep roots. We explore how sources and fate of soil CO2 vary with organic substrate source, abundance of respiring biota (i.e., roots and soil microbes), season, and soil depth. We quantified multiple isotopic signatures of CO2 (δ13C, Δ14C, δ18O) as well as concentrations and δ18O of free O2 in the upper 5 m of soil at sites where root abundances and soil organic C have been previously quantified: in late-successional forests, cultivated fields, and ~ 80 y old regenerating pine forests growing on previously cultivated land. We hypothesized that soil CO2sources would vary across soil depth and land cover, reflecting varying abundances of organic substrates, and seasonally as the dominance of root vs. microbial CO2 production changes through the year. δ13C–CO2 revealed respiration of C4-derived substrates in cultivated fields particularly during the growing season. This effect was not evident in soils of regenerating pine or older hardwood forests, suggesting that ~ 80 y of pine inputs to reforested soils have been sufficient to dominate microbial substrate selection over any remnant, historic agricultural C4 inputs. Δ14C–CO2 diverged by land use at 3 and 5 m, indicating that more recently-produced photosynthate is available for mineralization in forests compared to cultivated plots, and in late-successional forests compared to regenerating pine forests. At 1.5, 3, and 5 m in forested plots we observed evidence of respiratory demands on soil pore space O2. In these soils, we observed declines in [O2] compared to other depths and to the agricultural plots and concurrent increases in δ18O of free O2, consistent with the idea that roots and heterotrophic soil microbes are more active where photosynthate is more available. The δ18O–CO2 values, a likely proxy for δ18O of soil porewater, exhibited 18O enrichment during the winter, when many sampling wells were flooded, compared to growing season values. These data suggest an isotopically-distinct and laterally-flowing source of CO2-laden porewater during winter months. Combined, these datasets document how ~ 80 y of forest regeneration can provide sufficient C inputs to mask any microbial mineralization of decades-old organic inputs, but belowground C inputs still lag those of late successional forests. We also infer that lateral and vertical flows of water can serve as a sink for biotically-generated CO2, and that where deep soil [CO2] is lower due to lower root and microbial activities, production of carbonic acid is also diminished. Where reaction rates are weathering limited, a paucity of deep roots imposed by anthropogenic land cover change thus may limit the production of this agent of soil development and the C sink represented by the silicate weathering it can promote. The data suggest deep and persistent effects of the loss of deeply rooted long-lived vegetation on deep soil C storage and transformations that promote acid-dissolution weathering reactions that help form soil itself.

Tip tilt and focus estimation based on LGS and downlink joint measurements for ground to GEO satellite optical communication link.

Achieving high data rates in GEO Feeder optical uplinks faces challenges due to the fading nature of the channel induced by atmospheric turbulence. Adaptive optics pre-compensation using downlink measurements is a solution to mitigate the impact of the turbulence. However, the point-ahead angle anisoplanatism, inherent to the bidirectional link geometry, limits the uplink correction efficiency, leading to persistent signal fades and loss of information onboard the satellite. We recently proposed a new minimum mean square error method that improves the phase estimation at the PAA based on the downlink phase and log amplitude measurements, reducing the anisoplanatism impact on the coupled flux. Alternatively, a laser guide star can be used to measure the phase at the PAA. However, it is currently challenging to retrieve the tip, tilt, and focus modes, whose correction is essential to improve the link quality. In this article, we propose to combine both techniques to estimate the tip, tilt, and focus at the PAA by incorporating the LGS high-order measurements in the MMSE formalism. We develop the associated analytical reconstructor and evaluate the performance of the phase estimation and the gain on the coupled flux statistics aboard the GEO satellite, considering an idealized LGS system. The new estimator is shown to reduce the tip, tilt, and focus error variances by up to 70% of their initial value.

Combined inhibition of MET and VEGF enhances therapeutic efficacy of EGFR TKIs in EGFR-mutant non-small cell lung cancer with concomitant aberrant MET activation

Abstract Background Aberrant activation of mesenchymal epithelial transition (MET) has been considered to mediate primary and acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in EGFR-mutant non-small cell lung cancer (NSCLC). However, mechanisms underlying this process are not wholly clear and the effective therapeutic strategy remains to be determined. Methods The gefitinib-resistant NSCLC cell lines were induced by concentration increase method in vitro. Western blot and qPCR were used to investigate the relationship between MET and vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) signaling pathway. Double luciferase reporter gene and co-immunoprecipitation were used to further reveal the regulation mechanism between MET and VEGF/VEGFR2. The effect of combined inhibition of MET and VEGF/VEGFR2 signaling pathway on the therapeutic sensitivity of EGFR-TKI in gefitinib resistant cell lines with MET aberration was verified ex vivo and in vivo. Results We successfully obtained two gefitinib-resistant NSCLC cell lines with EGFR mutation and abnormal activation of MET. We observed that MET formed a positive feedback loop with the VEGF/VEGFR2 signaling, leading to persistent downstream signaling activation. Specifically, MET up-regulated VEGFR2 expression in a MAPK/ERK/ETS1-dependent manner, while VEGF promoted physical interaction between VEGFR2 and MET, thereby facilitating MET phosphorylation. A MET inhibitor, crizotinib, combined with an anti-VEGF antibody, bevacizumab, enhanced the sensitivity of NSCLC cells to gefitinib and synergistically inhibited the activation of downstream signaling in vitro. Dual inhibition of MET and VEGF combined with EGFR TKIs markedly restrained tumor growth in both human NSCLC xenograft models and in an EGFR/MET co-altered case. Conclusions Our work reveals a positive feedback loop between MET and VEGF/VEGFR2, resulting in continuous downstream signal activation. Combined inhibition of MET and VEGF/VEGFR2 signaling pathway may be beneficial for reversing EGFR TKIs resistance.

Long-term observations of the turbid outflow plume from the Russian River, California

Understanding the mechanisms that spread freshwater away from small river systems and form turbid, low-salinity coastal plumes is crucial for assessing water quality in coastal waters. We present an analysis of 15 years (January 2004 to December 2018) of daily MODIS Aqua satellite data and in situ instrument data on the turbid freshwater plume that forms off the Russian River (California, USA), a prototypical Mediterranean-climate, small mountainous river system (SMRS). We present per-pixel statistical metrics and regression analyses to identify and quantify the controls on the extent and configuration of the plume exerted by river discharge, waves, winds, and tides. While freshwater outflow exhibits a persistent signal in nearshore waters, a large-scale plume only extends offshore into coastal waters during high river flow, when plume turbidity can be detected more than 10 km offshore from the river mouth. Our results show times when wave radiation stress exceeds outflow inertia, confining the plume within the surf zone and leading to an absence of detectable plume turbidity in coastal waters. Although tidal currents significantly influence the plume near the inlet, wind forcing is the primary control on plume shape and extent in coastal waters, deflecting the turbid outflow more than 30 km upcoast or downcoast of the river mouth with respective wind directions. Coriolis forcing is also significant and observed most clearly during periods of high river discharge and low wind forcing. In addition to introducing novel remote sensing methodology for SMRS plume analyses, these findings highlight the complex interplay of forcing related to tides, river discharge, winds, and waves in shaping the behavior of SMRS plumes. New insights include the impact of tides on larger discharges, the role of Coriolis forcing in SMRS plumes, and the effect of cross-shore winds on plume compression. Further, by considering the Russian River as a model for SMRS, this study can be used to ground-truth existing numerical models of small river plumes and to contribute to understanding critical for managing coastal water quality and nearshore ecosystems.

Cyld restrains the hyperactivation of synovial fibroblasts in inflammatory arthritis by regulating the TAK1/IKK2 signaling axis

TNF is a potent cytokine known for its involvement in physiology and pathology. In Rheumatoid Arthritis (RA), persistent TNF signals cause aberrant activation of synovial fibroblasts (SFs), the resident cells crucially involved in the inflammatory and destructive responses of the affected synovial membrane. However, the molecular switches that control the pathogenic activation of SFs remain poorly defined. Cyld is a major component of deubiquitination (DUB) machinery regulating the signaling responses towards survival/inflammation and programmed necrosis that induced by cytokines, growth factors and microbial products. Herein, we follow functional genetic approaches to understand how Cyld affects arthritogenic TNF signaling in SFs. We demonstrate that in spontaneous and induced RA models, SF-Cyld DUB deficiency deteriorates arthritic phenotypes due to increased levels of chemokines, adhesion receptors and bone-degrading enzymes generated by mutant SFs. Mechanistically, Cyld serves to restrict the TNF-induced hyperactivation of SFs by limiting Tak1-mediated signaling, and, therefore, leading to supervised NF-κB and JNK activity. However, Cyld is not critically involved in the regulation of TNF-induced death of SFs. Our results identify SF-Cyld as a regulator of TNF-mediated arthritis and inform the signaling landscape underpinning the SF responses.

PD-1 controls differentiation, survival, and TCR affinity evolution of stem-like CD8+ T cells.

Stem-like progenitors are a critical subset of cytotoxic T cells that self-renew and give rise to expanded populations of effector cells critical for successful checkpoint blockade immunotherapy. Emerging evidence suggests that the tumor-draining lymph nodes can support the continuous generation of these stem-like cells that replenish the tumor sites and act as a critical source of expanded effector populations, underlining the importance of understanding what factors promote and maintain activated T cells in the stem-like state. Using advanced 3D multiplex immunofluorescence imaging, here we identified antigen-presentation niches in tumor-draining lymph nodes that support the expansion, maintenance, and affinity evolution of a unique population of TCF-1+PD-1+SLAMF6 hi stem-like CD8+ T cells. Our results show that contrary to the prevailing view that persistent TCR signaling drives terminal effector differentiation, prolonged antigen engagement well beyond the initial priming phase sustained the proliferation and self-renewal of these stem-like T cells in vivo . The inhibitory PD-1 pathway plays a central role in this process by mediating the fine-tuning of TCR and co-stimulatory signal input that enables selective expansion of high affinity TCR stem-like clones, enabling them to act as a renewable source of high affinity effector cells. PD-1 checkpoint blockade disrupts this fine tuning of input signaling, leading to terminal differentiation to the effector state or death of the most avid anti-tumor stem-like cells. Our results thus reveal an unexpected relationship between TCR ligand affinity recognition, a key negative feedback regulatory loop, and T cell stemness programming. Furthermore, these findings raise questions about whether anti-PD-1 checkpoint blockade during cancer immunotherapy provides a short-term anti-tumor effect that comes at the cost of diminishing efficacy due to progressive loss of these critical high affinity stem-like precursors.