Gut symbionts alleviate MASH through a secondary bile acid biosynthetic pathway.

The gut microbiota has been found to play an important role in the progression of metabolic dysfunction-associated steatohepatitis (MASH), but the mechanisms have not been established. Here, by developing a click-chemistry-based enrichment strategy, we identified several microbial-derived bile acids, including the previously uncharacterized 3-succinylated cholic acid (3-sucCA), which is negatively correlated with liver damage in patients with liver-tissue-biopsy-proven metabolic dysfunction-associated fatty liver disease (MAFLD). By screening human bacterial isolates, we identified Bacteroides uniformis strains as effective producers of 3-sucCA both in vitro and in vivo. By activity-based protein purification and identification, we identified an enzyme annotated as ß-lactamase in B. uniformis responsible for 3-sucCA biosynthesis. Furthermore, we found that 3-sucCA is a lumen-restricted metabolite and alleviates MASH by promoting the growth of Akkermansia muciniphila. Together, our data offer new insights into the gut microbiota-liver axis that may be leveraged to augment the management of MASH.

Gut bacteria alleviate smoking-related NASH by degrading gut nicotine.

Tobacco smoking is positively correlated with non-alcoholic fatty liver disease (NAFLD)1-5, but the underlying mechanism for this association is unclear. Here we report that nicotine accumulates in the intestine during tobacco smoking and activates intestinal AMPKα. We identify the gut bacterium Bacteroides xylanisolvens as an effective nicotine degrader. Colonization of B. xylanisolvens reduces intestinal nicotine concentrations in nicotine-exposed mice, and it improves nicotine-exacerbated NAFLD progression. Mechanistically, AMPKα promotes the phosphorylation of sphingomyelin phosphodiesterase 3 (SMPD3), stabilizing the latter and therefore increasing intestinal ceramide formation, which contributes to NAFLD progression to non-alcoholic steatohepatitis (NASH). Our results establish a role for intestinal nicotine accumulation in NAFLD progression and reveal an endogenous bacterium in the human intestine with the ability to metabolize nicotine. These findings suggest a possible route to reduce tobacco smoking-exacerbated NAFLD progression.

Role of Y box-binding protein 1 (Ybx1) in zebrafish folliculogenesis: Promoting follicle cell proliferation via suppression of p21 (cdkn1a).

Y box-binding protein 1 (YB-1; Ybx1/ybx1) regulates gene expression through DNA/RNA-binding. In zebrafish, Ybx1 is highly abundant in primary growth (PG) follicles in the ovary, but decreases precipitously as the follicles enter the secondary growth (SG). To understand Ybx1 function in folliculogenesis, we created an ybx1 mutant using TALEN and observed disrupted folliculogenesis during the previtellogenic (PV) to early vitellogenic (EV) transition of SG, resulting in underdeveloped ovaries and infertility. Expression and Western blot analyses revealed differential gene expression between ybx1-/- and control ovaries, with significantly increased expression of cdkn1a (p21), a cell cycle inhibitor, in ybx1-/- follicles. While cdkn1a knockout via CRISPR/Cas9 was embryonically lethal, the heterozygote (cdkn1a+/-) displayed advanced follicle activation and maturation, contrasting with the ybx1-/- phenotype. Partial loss of p21 alleviated the ybx1-/-phenotype, restoring folliculogenesis with normal PG-PV and PV-EV transitions in ybx1-/-;cdkn1a+/- mutant. While ybx1-/- mutant follicle cells displayed poor proliferation in vivo and in vitro, the cells from the ybx1-/-;p21+/- follicles resumed normal proliferation. In conclusion, Ybx1 is crucial for early folliculogenesis in zebrafish, potentially by repressing cdkn1a expression, either directly or indirectly.

Attention-guided variational graph autoencoders reveal heterogeneity in spatial transcriptomics.

The latest breakthroughs in spatially resolved transcriptomics technology offer comprehensive opportunities to delve into gene expression patterns within the tissue microenvironment. However, the precise identification of spatial domains within tissues remains challenging. In this study, we introduce AttentionVGAE (AVGN), which integrates slice images, spatial information and raw gene expression while calibrating low-quality gene expression. By combining the variational graph autoencoder with multi-head attention blocks (MHA blocks), AVGN captures spatial relationships in tissue gene expression, adaptively focusing on key features and alleviating the need for prior knowledge of cluster numbers, thereby achieving superior clustering performance. Particularly, AVGN attempts to balance the model's attention focus on local and global structures by utilizing MHA blocks, an aspect that current graph neural networks have not extensively addressed. Benchmark testing demonstrates its significant efficacy in elucidating tissue anatomy and interpreting tumor heterogeneity, indicating its potential in advancing spatial transcriptomics research and understanding complex biological phenomena.

The Toxoplasma protein phosphatase 6 catalytic subunit (TgPP6C) is essential for cell cycle progression and virulence.

Protein phosphatases are post-translational regulators of Toxoplasma gondii proliferation, tachyzoite-bradyzoite differentiation and pathogenesis. Here, we identify the putative protein phosphatase 6 (TgPP6) subunits of T. gondii and elucidate their role in the parasite lytic cycle. The putative catalytic subunit TgPP6C and regulatory subunit TgPP6R likely form a complex whereas the predicted structural subunit TgPP6S, with low homology to the human PP6 structural subunit, does not coassemble with TgPP6C and TgPP6R. Functional studies showed that TgPP6C and TgPP6R are essential for parasite growth and replication. The ablation of TgPP6C significantly reduced the synchronous division of the parasite's daughter cells during endodyogeny, resulting in disordered rosettes. Moreover, the six conserved motifs of TgPP6C were required for efficient endodyogeny. Phosphoproteomic analysis revealed that ablation of TgPP6C predominately altered the phosphorylation status of proteins involved in the regulation of the parasite cell cycle. Deletion of TgPP6C significantly attenuated the parasite virulence in mice. Immunization of mice with TgPP6C-deficient type I RH strain induced protective immunity against challenge with a lethal dose of RH or PYS tachyzoites and Pru cysts. Taken together, the results show that TgPP6C contributes to the cell division, replication and pathogenicity in T. gondii.

Flexible Tactile Sensors for 3D Force Detection.

As tactile force sensing has become increasingly significant in the field of machine haptics, achieving multidimensional force sensing remains a challenge. We propose a 3D flexible force sensor that consists of an axisymmetric hemispherical protrusion and four equally sized quarter-circle electrodes. By simulating the device using a force and electrical field model, it has been found that the magnitude and direction of the force can be expressed through the voltage relationship of the four electrodes when the magnitude of the shear force remains constant and its direction varies within 0-360°. The experimental results show that a resolution of 15° can be achieved in the range 0-90°. Additionally, we installed the sensor on a robotic hand, enabling it to perceive the magnitude and direction of touch and grasp actions. Based on this, the designed 3D flexible tactile force sensor provides valuable insights for multidimensional force detection and applications.

Comparative physiological, biochemical, metabolomic, and transcriptomic analyses reveal the formation mechanism of heartwood for Acacia melanoxylon.

Acacia melanoxylon is well known as a valuable commercial tree species owing to its high-quality heartwood (HW) products. However, the metabolism and regulatory mechanism of heartwood during wood development remain largely unclear. In this study, both microscopic observation and content determination proved that total amount of starches decreased and phenolics and flavonoids increased gradually from sapwood (SW) to HW. We also obtained the metabolite profiles of 10 metabolites related to phenolics and flavonoids during HW formation by metabolomics. Additionally, we collected a comprehensive overview of genes associated with the biosynthesis of sugars, terpenoids, phenolics, and flavonoids using RNA-seq. A total of ninety-one genes related to HW formation were identified. The transcripts related to plant hormones, programmed cell death (PCD), and dehydration were increased in transition zone (TZ) than in SW. The results of RT-PCR showed that the relative expression level of genes and transcription factors was also high in the TZ, regardless of the horizontal or vertical direction of the trunk. Therefore, the HW formation took place in the TZ for A. melanoxylon from molecular level, and potentially connected to plant hormones, PCD, and cell dehydration. Besides, the increased expression of sugar and terpenoid biosynthesis-related genes in TZ further confirmed the close connection between terpenoid biosynthesis and carbohydrate metabolites of A. melanoxylon. Furthermore, the integrated analysis of metabolism data and RNA-seq data showed the key transcription factors (TFs) regulating flavonoids and phenolics accumulation in HW, including negative correlation TFs (WRKY, MYB) and positive correlation TFs (AP2, bZIP, CBF, PB1, and TCP). And, the genes and metabolites from phenylpropanoid and flavonoid metabolism and biosynthesis were up-regulated and largely accumulated in TZ and HW, respectively. The findings of this research provide a basis for comprehending the buildup of metabolites and the molecular regulatory processes of HW formation in A. melanoxylon.

Recent Development of Biodegradable Occlusion Devices for Intra-Atrial Shunts.

Atrial septal defect (ASD) is the third most common type of structural congenital heart defect. Patent foramen ovale (PFO) is an anatomical anomaly in up to 25% of the general population. With the innovation of occlusion devices and improvement of transcatheter techniques, percutaneous closure has become a first-line therapeutic alternative for treatment of ASD and PFO. During the past few decades, the development of biodegradable occlusion devices has become a promising direction for transcatheter closure of ASD/PFO due to their biodegradability and improved biocompatibility. The purpose of this review is to comprehensively summarize biodegradable ASD/PFO occlusion devices, regarding device design, materials, biodegradability, and evaluation of animal or clinical experiments (if available). The current challenges and the research direction for the development of biodegradable occluders for congenital heart defects are also discussed.

Enhancing the tissue penetration to improve sonodynamic immunotherapy for pancreatic ductal adenocarcinoma using membrane-camouflaged nanoplatform.

PURPOSE: Sonodynamic therapy (SDT) is a promising strategy as an "in situ vaccine" to enhance activation of antitumor immune responses in solid tumors. However, the dense extracellular matrix (ECM) in pancreatic ductal adenocarcinoma (PDAC) lead to hypoxia and limited penetration of most drugs, aggravating the immunosuppressive tumor microenvironment and limiting the efficacy of synergistic sonodynamic immunotherapy. Therefore, it is essential to regulate ECM in order to alleviate tumor hypoxia and enhance the efficacy of sonodynamic immunotherapy for PDAC. METHODS: The CPIM nanoplatform, consisting of a macrophage membrane-coated oxygen and drug delivery system (CM@PFOB-ICG-α-Mangostin), was synthesized using ultrasound and extrusion methods. The in vivo homologous targeting and hypoxia alleviation capabilities of CPIM were evaluated through near-infrared (NIR) imaging and photoacoustic (PA) imaging. The tumor growth inhibition potential and ability to reprogram the tumor microenvironment by the CPIM nanoplatform were also investigated. RESULTS: Co-delivery of α-Mangostin inhibits CAFs and enhances stromal depletion, thereby facilitating better infiltration of macromolecules. Additionally, the nanoemulsion containing perfluorocarbon (PFC) can target tumor cells and accumulate within them through homologous targeting. The US irradiation results in the rapid release of oxygen, serving as a potential source of sonodynamic therapy for hypoxic tumors. Moreover, CPIM reshapes the immunosuppressive microenvironment increasing the population of cytotoxic T lymphocytes (CTLs), and enhancing their anti-tumor immune response through the use of anti-PDL1 antibodies to block immune checkpoints. CONCLUSION: The present study offers a potential strategy for the co-delivery of oxygen and α-Mangostin, aiming to enhance the penetration of tumors to improve SDT. This approach effectively addresses the existing limitations of immune checkpoint blockade (ICB) treatment in solid tumors, while simultaneously boosting the immune response through synergistic sonodynamic immunotherapy.

The antioxidant protein glutaredoxin 1 is essential for oxidative stress response and pathogenicity of Toxoplasma gondii.

Glutaredoxins (Grxs) are ubiquitous antioxidant proteins involved in many molecular processes to protect cells against oxidative damage. Here, we study the roles of Grxs in the pathogenicity of Toxoplasma gondii. We show that Grxs are localized in the mitochondria (Grx1), cytoplasm (Grx2), and apicoplast (Grx3, Grx4), while Grx5 had an undetectable level of expression. We generated Δgrx1-5 mutants of T. gondii type I RH and type II Pru strains using CRISPR-Cas9 system. No significant differences in the infectivity were detected between four Δgrx (grx2-grx5) strains and their respective wild-type (WT) strains in vitro or in vivo. Additionally, no differences were detected in the production of reactive oxygen species, total antioxidant capacity, superoxide dismutase activity, and sensitivity to external oxidative stimuli. Interestingly, RHΔgrx1 or PruΔgrx1 exhibited significant differences in all the investigated aspects compared to the other grx2-grx5 mutant and WT strains. Transcriptome analysis suggests that deletion of grx1 altered the expression of genes involved in transport and metabolic pathways, signal transduction, translation, and obsolete oxidation-reduction process. The data support the conclusion that grx1 supports T. gondii resistance to oxidative killing and is essential for the parasite growth in cultured cells and pathogenicity in mice and that the active site CGFS motif was necessary for Grx1 activity.

Exact test and exact confidence interval for the Cox model.

The Cox proportional hazards model is commonly used to analyze time-to-event data in clinical trials. Standard inference procedures for the Cox model are based on asymptotic approximations and may perform poorly when there are few events in one or both treatment groups, as may be the case when the event of interest is rare or when the experimental treatment is highly efficacious. In this article, we propose an exact test of equivalence and efficacy under a proportional hazard model with treatment effect as the only fixed effect, together with an exact confidence interval that is obtained by inverting the exact test. The proposed test is based on a conditional error method originally proposed for sample size reestimation problems. In the present context, the conditional error method is used to combine information from a sequence of hypergeometric distributions, one at each observed event time. The proposed procedures are evaluated in simulation studies and illustrated using real data from an HIV prevention trial. A companion R package "ExactCox" is available for download on CRAN.

A disposable paper-based electrochemical biosensor decorated by electrospun cellulose acetate nanofibers for highly sensitive bio-detection.

Paper-based electrochemical sensors have the characteristics of flexibility, biocompatibility, environmental protection, low cost, wide availability, and hydropathy, which make them very suitable for the development and application of biological detection. This work proposes electrospun cellulose acetate nanofiber (CA NF)-decorated paper-based screen-printed (PBSP) electrode electrochemical sensors. The CA NFs were directly collected on the PBSP electrode through an electrospinning technique at an optimized voltage of 16 kV for 10 min. The sensor was functionalized with different bio-sensitive materials for detecting different targets, and its sensing capability was evaluated by CV, DPV, and chronoamperometry methods. The test results demonstrated that the CA NFs enhanced the detection sensitivity of the PBSP electrode, and the sensor showed good stability, repeatability, and specificity (p < 0.01, N = 3). The electrochemical sensing of the CA NF-decorated PBSP electrode exhibited a short detection duration of ∼5-7 min and detection ranges of 1 nmol mL-1-100 µmol mL-1, 100 fg mL-1-10 µg mL-1, and 1.5 × 102-106 CFU mL-1 and limits of detection of 0.71 nmol mL-1, 89.1 fg mL-1, and 30 CFU mL-1 for glucose, Ag85B protein, and E. coli O157:H7, respectively. These CA NF-decorated PBSP sensors can be used as a general electrochemical tool to detect, for example, organic substances, proteins, and bacteria, which are expected to achieve point-of-care testing of pathogenic microorganisms and have wide application prospects in biomedicine, clinical diagnosis, environmental monitoring, and food safety.

Diiron Complexes with Rigid and Conjugated S-to-S Bridges for Electrocatalytic Reduction of CO2.

Electroreduction of CO2 to value-added low-carbon chemicals is a promising way for carbon neutrality and CO2 utilization. It was found that the diiron complex [(µ-bdt)Fe2(CO)6] (bdt = benzene-1,2-dithiolate) has high catalytic activity for electrocatalytic CO2 reduction. To further study the effect of the S-to-S bridge on the catalytic performances of diiron complexes for electrochemical CO2 reduction, four diiron complexes 1-4 with different rigid and conjugated S-to-S bridges were either selected or designed. The electrocatalytic studies showed that under optimal conditions, 2 with a 2,3-naphthalenedithiolato bridge exhibited the lowest catalytic onset potential (Eonset = -1.75 V vs Fc+/0), while 4 with a diphenyl-1,2-vinylidene bridge displayed the highest catalytic activity (TOFmax = 295 s-1), which is 1.5 times that of [(µ-bdt)Fe2(CO)6]. The controlled potential electrolysis experiments of 4 in 0.1 M MeOH/MeCN at -2.35 V vs Fc+/0 gave a total faradaic yield close to 100%, with selectivities of 77%, 9%, and 14% for HCOOH, CO, and H2, respectively. The mechanism for CO2 reduction was studied using density functional theory, IR spectroelectrochemistry, and electrochemical methods. The results indicate that modifying the structure of the S-to-S bridge is an effective strategy to improve the catalytic performance of diiron complexes for electrocatalytic CO2 reduction.

Portal vein velocity predicts portal vein system thrombosis after splenectomy with esophagogastric devascularization.

BACKGROUND: Portal vein system thrombosis (PVST) is a potentially fatal complication after splenectomy with esophagogastric devascularization (SED) in cirrhotic patients with portal hypertension. However, the impact of portal vein velocity (PVV) on PVST after SED remains unclear. Therefore, this study aims to explore this issue. METHODS: Consecutive cirrhotic patients with portal hypertension who underwent SED at Tongji Hospital between January 2010 and June 2022 were enrolled. The patients were divided into two groups based on the presence or absence of PVST, which was assessed using ultrasound or computed tomography after the operation. PVV was measured by duplex Doppler ultrasound within one week before surgery. The independent risk factors for PVST were analyzed using univariate and multivariate logistic regression analysis. A nomogram based on these variables was developed and internally validated using 1000 bootstrap resamples. RESULTS: A total of 562 cirrhotic patients with portal hypertension who underwent SED were included, and PVST occurred in 185 patients (32.9%). Multivariate logistic regression analysis showed that PVV was the strongest independent risk factor for PVST. The incidence of PVST was significantly higher in patients with PVV ≤ 16.5 cm/s than in those with PVV > 16.5 cm/s (76.2% vs. 8.5%, p < 0.0001). The PVV-based nomogram was internally validated and showed good performance (optimism-corrected c-statistic = 0.907). Decision curve and clinical impact curve analyses indicated that the nomogram provided a high clinical benefit. CONCLUSION: A nomogram based on PVV provided an excellent preoperative prediction of PVST after splenectomy with esophagogastric devascularization.

Mining and rational design of psychrophilic catalases using metagenomics and deep learning models.

A complete catalase-encoding gene, designated soiCat1, was obtained from soil samples via metagenomic sequencing, assembly, and gene prediction. soiCat1 showed 73% identity to a catalase-encoding gene of Mucilaginibacter rubeus strain P1, and the amino acid sequence of soiCAT1 showed 99% similarity to the catalase of a psychrophilic bacterium, Pedobacter cryoconitis. soiCAT1 was identified as a psychrophilic enzyme due to the low optimum temperature predicted by the deep learning model Preoptem, which was subsequently validated through analysis of enzymatic properties. Experimental results showed that soiCAT1 has a very narrow range of optimum temperature, with maximal specific activity occurring at the lowest test temperature (4 °C) and decreasing with increasing reaction temperature from 4 to 50 °C. To rationally design soiCAT1 with an improved temperature range, soiCAT1 was engineered through site-directed mutagenesis based on molecular evolution data analyzed through position-specific amino acid possibility calculation. Compared with the wild type, one mutant, soiCAT1S205K, exhibited an extended range of optimum temperature ranging from 4 to 20 °C. The strategies used in this study may shed light on the mining of genes of interest and rational design of desirable proteins. KEY POINTS: • Numerous putative catalases were mined from soil samples via metagenomics. • A complete sequence encoding a psychrophilic catalase was obtained. • A mutant psychrophilic catalase with an extended range of optimum temperature was engineered through site-directed mutagenesis.

Electrocardiographic characteristics of bladder cancer patients receiving preoperative chemotherapy combined with immunotherapy.

OBJECTIVE: Patients treated with preoperative chemotherapy and immunotherapy for bladder cancer may be at increased risk of cardiotoxicity and electrophysiological abnormalities. This study aimed to analyze their electrocardiographic (ECG) alterations. METHODS: Patients with bladder cancer who were hospitalized and receiving tislelizumab plus nab-paclitaxel (TnP) were enrolled prospectively. ECG, cardiac biomarkers, and echocardiography were performed at baseline and the end of TnP. RESULTS: A total of 60 patients (76.7% males), including 30 muscle-invasive and 30 non-muscle-invasive bladder cancer, received three or four cycles of TnP, respectively. Hypertension was the commonest comorbidity (41.7%), and 25 patients (41.7%) were prescribed cardiovascular drugs. In comparison with baseline characteristics, cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) were within normal ranges after TnP. However, echocardiographic parameter of left ventricular ejection fraction slightly decreased after TnP (62.81 ± 3.81% to 61.10 ± 4.37%, p = .011). The incidence of abnormal ECG increased from 65.0% at baseline to 76.7%, of which only a higher prevalence of fragmented QRS (fQRS) was observed (33.3% to 50.0%, p = .013; mainly in inferior leads). ECG parameters of QT dispersion (QTd) were prolonged significantly after the regimen (39.50 ± 11.37 to 44.20 ± 15.85 ms, p = .019). CONCLUSION: In bladder cancer patients receiving preoperative chemotherapy combined with immunotherapy, the main ECG abnormality was fQRS and QTd, with relatively normal cardiac biomarkers and echocardiographic parameters. Regular ECG screening should be carried out carefully to detect potential cardiotoxicity in the long-term follow-up.

High-fidelity source mask optimization for suppressing line-end shortening.

Source mask optimization (SMO) is a widely used computational lithography technique for compensating lithographic distortion. However, line-end shortening is still a key factor that cannot be easily corrected and affects the image fidelity of lithography at advanced nodes. This paper proposes a source mask optimization method that suppresses line-end shortening and improves lithography fidelity. An adaptive hybrid weight method is employed to increase the weights of the line end during the optimization, which adaptively updates the weights in each iteration according to the edge placement error (EPE). A cost function containing a penalty term based on the normalized image log slope (NILS) is established to ensure the fidelity of the overall feature when paying more attention to the line-end region. The scope of this penalty term is regulated by widening and extending the split contour to further reduce the line-end shortening. Simulation results show that the proposed method can effectively suppress the line-end shortening and improve the lithography fidelity compared with the traditional SMO method.

A programmable pAgo nuclease with RNA target preference from the psychrotolerant bacterium Mucilaginibacter paludis.

Argonaute (Ago) proteins are programmable nucleases found in eukaryotes and prokaryotes. Prokaryotic Agos (pAgos) share a high degree of structural homology with eukaryotic Agos (eAgos), and eAgos originate from pAgos. Although eAgos exclusively cleave RNA targets, most characterized pAgos cleave DNA targets. This study characterized a novel pAgo, MbpAgo, from the psychrotolerant bacterium Mucilaginibacter paludis which prefers to cleave RNA targets rather than DNA targets. Compared to previously studied Agos, MbpAgo can utilize both 5'phosphorylated(5'P) and 5'hydroxylated(5'OH) DNA guides (gDNAs) to efficiently cleave RNA targets at the canonical cleavage site if the guide is between 15 and 17 nt long. Furthermore, MbpAgo is active at a wide range of temperatures (4-65°C) and displays no obvious preference for the 5'-nucleotide of a guide. Single-nucleotide and most dinucleotide mismatches have no or little effects on cleavage efficiency, except for dinucleotide mismatches at positions 11-13 that dramatically reduce target cleavage. MbpAgo can efficiently cleave highly structured RNA targets using both 5'P and 5'OH gDNAs in the presence of Mg2+ or Mn2+. The biochemical characterization of MbpAgo paves the way for its use in RNA manipulations such as nucleic acid detection and clearance of RNA viruses.

CPSF6-mediated XBP1 3'UTR shortening attenuates cisplatin-induced ER stress and elevates chemo-resistance in lung adenocarcinoma.

Alternative polyadenylation (APA) is a widespread mechanism generating RNA molecules with alternative 3' ends. Herein, we discovered that TargetScan includes a novel XBP1 transcript with a longer 3' untranslated region (UTR) (XBP1-UL) than that included in NCBI. XBP1-UL exhibited a lowered level in blood samples from lung adenocarcinoma (LUAD) patients and in those after DDP treatment. Consistently, XBP1-UL was reduced in A549 cells compared to normal BEAS-2B cells, as well as in DDP-treated/resistant A549 cells relative to controls. Moreover, due to decreased usage of the distal polyadenylation site (PAS) in 3'UTR, XBP1-UL level was lowered in A549 cells and decreased further in DDP-resistant A549 (A549/DDP) cells. Importantly, use of the distal PAS (dPAS) and XBP1-UL level were gradually reduced in A549 cells under increasing concentrations of DDP, which was attributed to DDP-induced endoplasmic reticulum (ER) stress. Furthermore, XBP1 transcripts with shorter 3'UTR (XBP1-US) were more stable and presented stronger potentiation on DDP resistance. The choice of proximal PAS (pPAS) was attributed to CPSF6 elevation, which was caused by BRCA1-distrupted R-loop accumulation in CPSF6 5'end. DDP-induced nuclear LINC00221 also facilitated CPSF6-induced pPAS choice in the pre-XBP1 3'end. Finally, we found that unlike the unspliced XBP1 protein (XBP1-u), the spliced form XBP1-s retarded p53 degradation to facilitate DNA damage repair of LUAD cells. The current study provides new insights into tumor progression and DDP resistance in LUAD, which may contribute to improved LUAD treatment.

A quantitative systems pharmacology model of plasma kallikrein-kinin system dysregulation in hereditary angioedema.

Hereditary angioedema (HAE) due to C1-inhibitor deficiency is a rare, debilitating, genetic disorder characterized by recurrent, unpredictable, attacks of edema. The clinical symptoms of HAE arise from excess bradykinin generation due to dysregulation of the plasma kallikrein-kinin system (KKS). A quantitative systems pharmacology (QSP) model that mechanistically describes the KKS and its role in HAE pathophysiology was developed based on HAE attacks being triggered by autoactivation of factor XII (FXII) to activated FXII (FXIIa), resulting in kallikrein production from prekallikrein. A base pharmacodynamic model was constructed and parameterized from literature data and ex vivo assays measuring inhibition of kallikrein activity in plasma of HAE patients or healthy volunteers who received lanadelumab. HAE attacks were simulated using a virtual patient population, with attacks recorded when systemic bradykinin levels exceeded 20 pM. The model was validated by comparing the simulations to observations from lanadelumab and plasma-derived C1-inhibitor clinical trials. The model was then applied to analyze the impact of nonadherence to a daily oral preventive therapy; simulations showed a correlation between the number of missed doses per month and reduced drug effectiveness. The impact of reducing lanadelumab dosing frequency from 300 mg every 2 weeks (Q2W) to every 4 weeks (Q4W) was also examined and showed that while attack rates with Q4W dosing were substantially reduced, the extent of reduction was greater with Q2W dosing. Overall, the QSP model showed good agreement with clinical data and could be used for hypothesis testing and outcome predictions.