Mechanism for the Regulated Control of Bacterial Transcription Termination by a Universal Adaptor Protein.

NusG/Spt5 proteins are the only transcription factors utilized by all cellular organisms. In enterobacteria, NusG antagonizes the transcription termination activity of Rho, a hexameric helicase, during the synthesis of ribosomal and actively translated mRNAs. Paradoxically, NusG helps Rho act on untranslated transcripts, including non-canonical antisense RNAs and those arising from translational stress; how NusG fulfills these disparate functions is unknown. Here, we demonstrate that NusG activates Rho by assisting helicase isomerization from an open-ring, RNA-loading state to a closed-ring, catalytically active translocase. A crystal structure of closed-ring Rho in complex with NusG reveals the physical basis for this activation and further explains how Rho is excluded from translationally competent RNAs. This study demonstrates how a universally conserved transcription factor acts to modulate the activity of a ring-shaped ATPase motor and establishes how the innate sequence bias of a termination factor can be modulated to silence pervasive, aberrant transcription.

The molecular mechanism for TERRA recruitment and annealing to telomeres.

Telomeric repeat containing RNA (TERRA) is a noncoding RNA that is transcribed from telomeres. Previous study showed that TERRA trans anneals by invading into the telomeric duplex to form an R-loop in mammalian cells. Here, we elucidate the molecular mechanism underlying TERRA recruitment and invasion into telomeres in the context of shelterin proteins, RAD51 and RNase H using single molecule (sm) assays. We demonstrate that TERRA trans annealing into telomeric DNA exhibits dynamic movement that is stabilized by TRF2. TERRA annealing to the telomeric duplex results in the formation of a stable triplex structure which differs from a conventional R-loop. We identified that the presence of a sub-telomeric DNA and a telomeric overhang in the form of a G-quadruplex significantly enhances TERRA annealing to telomeric duplex. We also demonstrate that RAD51-TERRA complex invades telomere duplex more efficiently than TERRA alone. Additionally, TRF2 increases TERRA affinity to telomeric duplex and protects it from RNase H digestion. In contrast, TRF1 represses TERRA annealing to telomeric duplex and fails to provide protection against RNase H digestion. Our findings provide an in-depth molecular mechanism underpinning TERRA recruitment and annealing to the telomere.

Integrating comparative modeling and accelerated simulations reveals conformational and energetic basis of actomyosin force generation.

Muscle contraction is performed by arrays of contractile proteins in the sarcomere. Serious heart diseases, such as cardiomyopathy, can often be results of mutations in myosin and actin. Direct characterization of how small changes in the myosin-actin complex impact its force production remains challenging. Molecular dynamics (MD) simulations, although capable of studying protein structure-function relationships, are limited owing to the slow timescale of the myosin cycle as well as a lack of various intermediate structures for the actomyosin complex. Here, employing comparative modeling and enhanced sampling MD simulations, we show how the human cardiac myosin generates force during the mechanochemical cycle. Initial conformational ensembles for different myosin-actin states are learned from multiple structural templates with Rosetta. This enables us to efficiently sample the energy landscape of the system using Gaussian accelerated MD. Key myosin loop residues, whose substitutions are related to cardiomyopathy, are identified to form stable or metastable interactions with the actin surface. We find that the actin-binding cleft closure is allosterically coupled to the myosin motor core transitions and ATP-hydrolysis product release from the active site. Furthermore, a gate between switch I and switch II is suggested to control phosphate release at the prepowerstroke state. Our approach demonstrates the ability to link sequence and structural information to motor functions.

Free-standing membrane incorporating single-atom catalysts for ultrafast electroreduction of low-concentration nitrate.

The release of wastewaters containing relatively low levels of nitrate (NO3-) results in sufficient contamination to induce harmful algal blooms and to elevate drinking water NO3- concentrations to potentially hazardous levels. In particular, the facile triggering of algal blooms by ultra-low concentrations of NO3- necessitates the development of efficient methods for NO3- destruction. However, promising electrochemical methods suffer from weak mass transport under low reactant concentrations, resulting in long treatment times (on the order of hours) for complete NO3- destruction. In this study, we present flow-through electrofiltration via an electrified membrane incorporating nonprecious metal single-atom catalysts for NO3- reduction activity enhancement and selectivity modification, achieving near-complete removal of ultra-low concentration NO3- (10 mg-N L-1) with a residence time of only a few seconds (10 s). By anchoring Cu single atoms supported on N-doped carbon in a carbon nanotube interwoven framework, we fabricate a free-standing carbonaceous membrane featuring high conductivity, permeability, and flexibility. The membrane achieves over 97% NO3- removal with high N2 selectivity of 86% in a single-pass electrofiltration, which is a significant improvement over flow-by operation (30% NO3- removal with 7% N2 selectivity). This high NO3- reduction performance is attributed to the greater adsorption and transport of nitric oxide under high molecular collision frequency coupled with a balanced supply of atomic hydrogen through H2 dissociation during electrofiltration. Overall, our findings provide a paradigm of applying a flow-through electrified membrane incorporating single-atom catalysts to improve the rate and selectivity of NO3- reduction for efficient water purification.

A DNA origami device spatially controls CD95 signalling to induce immune tolerance in rheumatoid arthritis.

DNA origami is capable of spatially organizing molecules into sophisticated geometric patterns with nanometric precision. Here we describe a reconfigurable, two-dimensional DNA origami with geometrically patterned CD95 ligands that regulates immune cell signalling to alleviate rheumatoid arthritis. In response to pH changes, the device reversibly transforms from a closed to an open configuration, displaying a hexagonal pattern of CD95 ligands with ~10 nm intermolecular spacing, precisely mirroring the spatial arrangement of CD95 receptor clusters on the surface of immune cells. In a collagen-induced arthritis mouse model, DNA origami elicits robust and selective activation of CD95 death-inducing signalling in activated immune cells located in inflamed synovial tissues. Such localized immune tolerance ameliorates joint damage with no noticeable side effects. This device allows for the precise spatial control of cellular signalling, expanding our understanding of ligand-receptor interactions and is a promising platform for the development of pharmacological interventions targeting these interactions.

The maize single-nucleus transcriptome comprehensively describes signaling networks governing movement and development of grass stomata.

The unique morphology of grass stomata enables rapid responses to environmental changes. Deciphering the basis for these responses is critical for improving food security. We have developed a planta platform of single-nucleus RNA-sequencing by combined fluorescence-activated nuclei flow sorting, and used it to identify cell types in mature and developing stomata from 33,098 nuclei of the maize epidermis-enriched tissues. Guard cells (GCs) and subsidiary cells (SCs) displayed differential expression of genes, besides those encoding transporters, involved in the abscisic acid, CO2, Ca2+, starch metabolism, and blue light signaling pathways, implicating coordinated signal integration in speedy stomatal responses, and of genes affecting cell wall plasticity, implying a more sophisticated relationship between GCs and SCs in stomatal development and dumbbell-shaped guard cell formation. The trajectory of stomatal development identified in young tissues, and by comparison to the bulk RNA-seq data of the MUTE defective mutant in stomatal development, confirmed known features, and shed light on key participants in stomatal development. Our study provides a valuable, comprehensive, and fundamental foundation for further insights into grass stomatal function.

Role of the leucine-rich repeat protein kinase 2 C-terminal tail in domain cross-talk.

Leucine-rich repeat protein kinase 2 (LRRK2) is a multi-domain protein encompassing two of biology's most critical molecular switches, a kinase and a GTPase, and mutations in LRRK2 are key players in the pathogenesis of Parkinson's disease (PD). The availability of multiple structures (full-length and truncated) has opened doors to explore intra-domain cross-talk in LRRK2. A helix extending from the WD40 domain and stably docking onto the kinase domain is common in all available structures. This C-terminal (Ct) helix is a hub of phosphorylation and organelle-localization motifs and thus serves as a multi-functional protein : protein interaction module. To examine its intra-domain interactions, we have recombinantly expressed a stable Ct motif (residues 2480-2527) and used peptide arrays to identify specific binding sites. We have identified a potential interaction site between the Ct helix and a loop in the CORB domain (CORB loop) using a combination of Gaussian accelerated molecular dynamics simulations and peptide arrays. This Ct-Motif contains two auto-phosphorylation sites (T2483 and T2524), and T2524 is a 14-3-3 binding site. The Ct helix, CORB loop, and the CORB-kinase linker together form a part of a dynamic 'CAP' that regulates the N-lobe of the kinase domain. We hypothesize that in inactive, full-length LRRK2, the Ct-helix will also mediate interactions with the N-terminal armadillo, ankyrin, and LRR domains (NTDs) and that binding of Rab substrates, PD mutations, or kinase inhibitors will unleash the NTDs.

Fibroblast growth factor receptor 1 inhibition suppresses pancreatic cancer chemoresistance and chemotherapy-driven aggressiveness.

AIMS: Pancreatic ductal adenocarcinoma (PDAC) is often intrinsically-resistant to standard-of-care chemotherapies such as gemcitabine. Acquired gemcitabine resistance (GemR) can arise from treatment of initially-sensitive tumors, and chemotherapy can increase tumor aggressiveness. We investigated the molecular mechanisms of chemoresistance and chemotherapy-driven tumor aggressiveness, which are understood incompletely. METHODS: Differential proteomic analysis was employed to investigate chemotherapy-driven chemoresistance drivers and responses of PDAC cells and patient-derived tumor xenografts (PDX) having different chemosensitivities. We also investigated the prognostic value of FGFR1 expression in the efficacy of selective pan-FGFR inhibitor (FGFRi)-gemcitabine combinations. RESULTS: Quantitative proteomic analysis of a highly-GemR cell line revealed fibroblast growth factor receptor 1 (FGFR1) as the highest-expressed receptor tyrosine kinase. FGFR1 knockdown or FGFRi co-treatment enhanced gemcitabine efficacy and decreased GemR marker expression, implicating FGFR1 in augmentation of GemR. FGFRi treatment reduced PDX tumor progression and prolonged survival significantly, even in highly-resistant tumors in which neither single-agent showed efficacy. Gemcitabine exacerbated aggressiveness of highly-GemR tumors, based upon proliferation and metastatic markers. Combining FGFRi with gemcitabine or gemcitabine+nab-paclitaxel reversed tumor aggressiveness and progression, and prolonged survival significantly. In multiple PDAC PDXs, FGFR1 expression correlated with intrinsic tumor gemcitabine sensitivity. CONCLUSION: FGFR1 drives chemoresistance and tumor aggressiveness, which FGFRi can reverse.

Deciphering adipose development: Function, differentiation and regulation.

The overdevelopment of adipose tissues, accompanied by excess lipid accumulation and energy storage, leads to adipose deposition and obesity. With the increasing incidence of obesity in recent years, obesity is becoming a major risk factor for human health, causing various relevant diseases (including hypertension, diabetes, osteoarthritis and cancers). Therefore, it is of significance to antagonize obesity to reduce the risk of obesity-related diseases. Excess lipid accumulation in adipose tissues is mediated by adipocyte hypertrophy (expansion of pre-existing adipocytes) or hyperplasia (increase of newly-formed adipocytes). It is necessary to prevent excessive accumulation of adipose tissues by controlling adipose development. Adipogenesis is exquisitely regulated by many factors in vivo and in vitro, including hormones, cytokines, gender and dietary components. The present review has concluded a comprehensive understanding of adipose development including its origin, classification, distribution, function, differentiation and molecular mechanisms underlying adipogenesis, which may provide potential therapeutic strategies for harnessing obesity without impairing adipose tissue function.

A Type I Photosensitizer-Polymersome Boosts Reactive Oxygen Species Generation by Forcing H-Aggregation for Amplifying STING Immunotherapy.

Activation of the innate immune Stimulator of Interferon Genes (STING) pathway potentiates antitumor immunity. However, delivering STING agonists systemically to tumors presents a formidable challenge, and resistance to STING monotherapy has emerged in clinical trials with diminishing natural killer (NK) cell proliferation. Here, we encapsulated the STING agonist diABZI within polymersomes containing a Type I photosensitizer (NBS), creating a nanoagonist (PNBS/diABZI) for highly responsive tumor immunotherapy. This structure promoted H-aggregation and intersystem crossing of NBS, resulting in a ∼ 3-fold amplification in superoxide anion and singlet oxygen generation. The photodynamic therapy directly damaged hypoxia tumor cells and stimulated the proliferation of NK cells and cytotoxic T lymphocytes, thereby sensitizing STING immunotherapy. A single systemic intravenous administration of PNBS/diABZI eradicated orthotopic mammary tumors in murine models, achieving long-term antitumor immune memory to inhibit tumor recurrence and metastasis and significantly improving long-term tumor-free survival. This work provides a design rule for boosting reactive oxygen species production by promoting the intersystem crossing process, highlighting the potential of Type I photosensitizer-polymer vehicles for augmenting STING immunotherapy.

Mild hypothermia reduces lipopolysaccharide-induced microglial activation via down-regulation of Tent5c.

Microglial activation is a critical factor in the pathogenesis and progression of neuroinflammatory diseases. Mild hypothermia, known for its neuroprotective properties, has been shown to alleviate microglial activation. In this study, we explore the differentially expressed (DE) mRNAs and long non-coding RNAs (lncRNAs) in BV-2 microglial cells under different conditions: normal temperature (CN), mild hypothermia (YT), normal temperature with lipopolysaccharide (LPS), and mild hypothermia with LPS (LPS + YT). Venn analysis revealed 119 DE mRNAs that were down-regulated in the LPS + YT vs LPS comparison but up-regulated in the CN vs LPS comparison, primarily enriched in Gene Ontology terms related to immune and inflammatory responses. Furthermore, through Venn analysis of YT vs CN and LPS + YT vs LPS comparisons, we identified 178 DE mRNAs and 432 DE lncRNAs. Among these transcripts, we validated the expression of Tent5c at the protein and mRNA levels. Additionally, siRNA-knockdown of Tent5c attenuated the expression of pro-inflammatory genes (TNF-α, IL-1ß, Agrn, and Fpr2), cellular morphological changes, NLRP3 and p-P65 protein levels, immunofluorescence staining of p-P65 and number of cells with ASC-speck induced by LPS. Furthermore, Tent5c overexpression further potentiated the aforementioned indicators in the context of mild hypothermia with LPS treatment. Collectively, our findings highlight the significant role of Tent5c down-regulation in mediating the anti-inflammatory effects of mild hypothermia.

Transcriptome sequencing and metabolome analysis reveal the molecular mechanism of Salvia miltiorrhiza in response to drought stress.

Salvia miltiorrhiza is commonly used as a Chinese herbal medicine to treat different cardiovascular and cerebrovascular illnesses due to its active ingredients. Environmental conditions, especially drought stress, can affect the yield and quality of S. miltiorrhiza. However, moderate drought stress could improve the quality of S. miltiorrhiza without significantly reducing the yield, and the mechanism of this initial drought resistance is still unclear. In our study, transcriptome and metabolome analyses of S. miltiorrhiza under different drought treatment groups (CK, A, B, and C groups) were conducted to reveal the basis for its drought tolerance. We discovered that the leaves of S. miltiorrhiza under different drought treatment groups had no obvious shrinkage, and the malondialdehyde (MDA) contents as well as superoxide dismutase (SOD) and peroxidase (POD) activities dramatically increased, indicating that our drought treatment methods were moderate, and the leaves of S. miltiorrhiza began to initiate drought resistance. The morphology of root tissue had no significant change under different drought treatment groups, and the contents of four tanshinones significantly enhanced. In all, 5213, 6611, and 5241 differentially expressed genes (DEGs) were shared in the A, B, and C groups compared with the CK group, respectively. The results of KEGG and co-expression analysis showed that the DEGs involved in plant-pathogen interactions, the MAPK signaling pathway, phenylpropanoid biosynthesis, flavonoid biosynthesis, and plant hormone signal transduction responded to drought stress and were strongly correlated with tanshinone biosynthesis. Furthermore, the results of metabolism analysis indicated that 67, 72, and 92 differentially accumulated metabolites (DAMs), including fumarate, ferulic acid, xanthohumol, and phytocassanes, which were primarily involved in phenylpropanoid biosynthesis, flavonoid biosynthesis, and diterpenoid biosynthesis pathways, were detected in these groups. These discoveries provide valuable information on the molecular mechanisms by which S. miltiorrhiza responds to drought stress and will facilitate the development of drought-resistant and high-quality S. miltiorrhiza production.

A Hydrogel-coated Wood Membrane with Intelligent Oil Pollution Detection for Emulsion Separation.

Considering the potential threats posed by oily wastewater to the ecosystem, it is urgently in demand to develop efficient, eco-friendly, and intelligent oil/water separation materials to enhance the safety of the water environment. Herein, an intelligent hydrogel-coated wood (PPT/PPy@DW) membrane with self-healing, self-cleaning, and oil pollution detection performances is fabricated for the controllable separation of oil-in-water (O/W) emulsions and water-in-oil (W/O) emulsions. The PPT/PPy@DW is prepared by loading polypyrrole (PPy) particles on the delignified wood (DW) membranes, further modifying the hydrogel layer as an oil-repellent barrier. The layered porous structure and selective wettability endow PPT/PPy@DW with great separation performance for various O/W emulsions (≥98.69% for separation efficiency and ≈1000 L m-2 h-1 bar-1 for permeance). Notably, the oil pollution degree of PPT/PPy@DW can be monitored in real-time based on the changed voltage generated during O/W emulsion separation, and the oil-polluted PPT/PPy@DW can be self-cleaned by soaking in water to recover its separation performance. The high affinity of PPT/PPy@DW for water makes it effective in trapping water from the mixed surfactant-stabilized W/O emulsions. The prepared eco-friendly and low-cost multifunctional hydrogel wood membrane shows promising potential in on-demand oil/water separation and provides new ideas for the functional improvement of new biomass oil/water separation membrane materials.

Engineering Sonosensitizer-Derived Nanotheranostics for Augmented Sonodynamic Therapy.

Sonodynamic therapy (SDT), featuring noninvasive, deeper penetration, low cost, and repeatability, is a promising therapy approach for deep-seated tumors. However, the general or only utilization of SDT shows low efficiency and unsatisfactory treatment outcomes due to the complicated tumor microenvironment (TME) and SDT process. To circumvent the issues, three feasible approaches for enhancing SDT-based therapeutic effects, including sonosensitizer optimization, strategies for conquering hypoxia TME, and combinational therapy are summarized, with a particular focus on the combination therapy of SDT with other therapy modalities, including chemodynamic therapy, photodynamic therapy, photothermal therapy, chemotherapy, starvation therapy, gas therapy, and immunotherapy. In the end, the current challenges in SDT-based therapy on tumors are discussed and feasible approaches for enhanced therapeutic effects are provided. It is envisioned that this review will provide new insight into the strategic design of high-efficiency sonosensitizer-derived nanotheranostics, thereby augmenting SDT and accelerating the potential clinical transformation.

Integrative analyses of bulk and single-cell transcriptomics reveals the infiltration and crosstalk of cancer-associated fibroblasts as a novel predictor for prognosis and microenvironment remodeling in intrahepatic cholangiocarcinoma.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is a highly malignant neoplasm and characterized by desmoplastic matrix. The heterogeneity and crosstalk of tumor microenvironment remain incompletely understood. METHODS: To address this gap, we performed Weighted Gene Co-expression Network Analysis (WGCNA) to identify and construct a cancer associated fibroblasts (CAFs) infiltration biomarker. We also depicted the intercellular communication network and important receptor-ligand complexes using the single-cell transcriptomics analysis of tumor and Adjacent normal tissue. RESULTS: Through the intersection of TCGA DEGs and WGCNA module genes, 784 differential genes related to CAFs infiltration were obtained. After a series of regression analyses, the CAFs score was generated by integrating the expressions of EVA1A, APBA2, LRRTM4, GOLGA8M, BPIFB2, and their corresponding coefficients. In the TCGA-CHOL, GSE89748, and 107,943 cohorts, the high CAFs score group showed unfavorable survival prognosis (p < 0.001, p = 0.0074, p = 0.028, respectively). Additionally, a series of drugs have been predicted to be more sensitive to the high-risk group (p < 0.05). Subsequent to dimension reduction and clustering, thirteen clusters were identified to construct the single-cell atlas. Cell-cell interaction analysis unveiled significant enhancement of signal transduction in tumor tissues, particularly from fibroblasts to malignant cells via diverse pathways. Moreover, SCENIC analysis indicated that HOXA5, WT1, and LHX2 are fibroblast specific motifs. CONCLUSIONS: This study reveals the key role of fibroblasts - oncocytes interaction in the remodeling of the immunosuppressive microenvironment in intrahepatic cholangiocarcinoma. Subsequently, it may trigger cascade activation of downstream signaling pathways such as PI3K-AKT and Notch in tumor, thus initiating tumorigenesis. Targeted drugs aimed at disrupting fibroblasts-tumor cell interaction, along with associated enrichment pathways, show potential in mitigating the immunosuppressive microenvironment that facilitates tumor progression.

Transcriptomic features of systemic lupus erythematosus patients in flare and changes during acute in-hospital treatment.

OBJECTIVES: Systemic lupus erythematosus (SLE) is a complex autoimmune disease with varying symptoms and multi-organ damage. Relapse-remission cycles often persist for many patients for years with the current treatment. Improved understanding of molecular changes caused by SLE flare and intensive treatment may result in more targeted therapies. METHODS: RNA sequencing was performed on peripheral blood mononuclear cells (PBMCs) from 65 SLE patients in flare, collected both before (SLE1) and after (SLE2) in-hospital treatment, along with 15 healthy controls (HC). Differentially expressed genes (DEGs) were identified among the three groups. Enriched functions and key molecular signatures of the DEGs were analysed and scored to elucidate the transcriptomic changes during treatment. RESULTS: Few upregulated genes in SLE1 vs HC were affected by treatment (SLE2 vs SLE1), mostly functional in interferon signalling (IFN), plasmablasts and neutrophils. IFN and plasmablast signatures were repressed, but the neutrophil signature remained unchanged or enhanced by treatment. The IFN and neutrophil scores together stratified the SLE samples. IFN scores correlated well with leukopenia, while neutrophil scores reflected relative cell compositions but not cell counts. CONCLUSIONS: In-hospital treatment significantly relieved SLE symptoms with expression changes of a small subset of genes. Notably, IFN signature changes matched SLE flare and improvement, while enhanced neutrophil signature upon treatment suggested the involvement of low-density granulocytes (LDG) in disease development.

Total Three-Dimensional-Guided Laparoscopic Radical Resection for Left Perihilar Cholangiocarcinoma.

BACKGROUND: The application of three-dimensional (3D) reconstruction has been extensively adopted in hepatectomy navigation,1 yet its utilization in laparoscopic radical resection of perihilar cholangiocarcinoma (pHCCA) remains underexplored. VIDEO: A 54-year-old male patient, classified as Child-Pugh B, presented a small neoplasm situated at the left hepatic duct proximate to the right hepatic and common hepatic ducts. An enhanced abdominal computed tomographic scan identified a solitary lesion measuring 2.8 × 2.4 cm. 3D reconstruction exposed tumor invasion into the left hepatic artery and left portal vein. Given the lesion's unique location, a pure laparoscopic left hepatectomy and caudate lobectomy were executed using a no-touch en block technique post patient consent. Concurrently, extrahepatic bile duct resection, radical lymphadenectomy with skeletonization, and biliary reconstruction were performed. RESULTS: The 3D reconstruction-guided laparoscopic left hepatectomy and caudate lobectomy were successfully completed in 425 min with minimal blood loss (50 mL). The histological grading was T2bN0M0 (stage II). The patient was discharged on the sixth postoperative day without complications, and postoperative treatment included mono-drug chemotherapy with capecitabine. No recurrence was observed at the 6-month follow-up. CONCLUSION: Our experience suggests that 3D reconstruction-guided laparoscopic radical resection may offer increased precision and efficiency in selected pHCCA patients. This approach can potentially yield outcomes comparable with or superior to open surgery, given standardized lymph node dissection by skeletonization, use of the no-touch en block technique, appropriate digestive tract reconstruction, and reduced bleeding and liver damage.

Prognostic Significance of Tumor Necrosis in Patients with Gallbladder Carcinoma Undergoing Curative-Intent Resection.

BACKGROUND: Tumor necrosis has been indicated to correlate with dismal survival outcomes of a variety of solid tumors. However, the significance and prognostic value of tumor necrosis remain unclear in gallbladder carcinoma. The aim of this research is to explore the relationships between necrosis with long-term survival and tumor-related biological characteristics of patients with gallbladder carcinoma. PATIENTS AND METHODS: Patients with gallbladder carcinoma who accepted curative-intent resection in West China Hospital of Sichuan University (China) between January 2010 and December 2021 were retrospectively analyzed. Tumor necrosis was determined by staining the patient's original tissue sections with hematoxylin and eosin. Based on the presence of tumor necrosis, the pathologic features and survival outcomes were compared. RESULTS: This study enrolled 213 patients with gallbladder carcinoma who underwent curative-intent surgery, of whom 89 had tumor necrosis. Comparative analyses indicated that patients with tumor necrosis had more aggressive clinicopathological features, such as larger tumor size (p = 0.002), poorer tumor differentiation (p = 0.029), more frequent vascular invasion (p < 0.001), presence of lymph node metastasis (p = 0.014), and higher tumor status (p = 0.01), and experienced poorer survival. Univariate and multivariate analyses revealed that tumor necrosis was an independent prognostic factor for overall survival (multivariate: HR 1.651, p = 0.026) and disease-free survival (multivariate: HR 1.589, p = 0.040). CONCLUSIONS: Tumor necrosis can be considered as an independent predictive factor for overall survival and disease-free survival among individuals with gallbladder carcinoma, which was a valuable pathologic parameter.

Interdependence between myocardial deformation and perfusion in patients with T2DM and HFpEF: a feature-tracking and stress perfusion CMR study.

BACKGROUND: Patients with diabetes have an increased risk of developing heart failure with preserved ejection fraction (HFpEF). This study aimed to compare indices of myocardial deformation and perfusion between patients with type 2 diabetes mellitus (T2DM) with and without HFpEF and to investigate the relationship between myocardial strain and perfusion reserve. METHODS: This study included 156 patients with T2DM without obstructive coronary artery disease (CAD) and 50 healthy volunteers who underwent cardiac magnetic resonance (CMR) examination at our center. Patients with T2DM were subdivided into the T2DM-HFpEF (n = 74) and the T2DM-non-HFpEF (n = 82) groups. The parameters of left ventricular (LV) and left atrial (LA) strain as well as stress myocardial perfusion were compared. The correlation between myocardial deformation and perfusion parameters was also assessed. Mediation analyses were used to evaluate the direct and indirect effects of T2DM on LA strain. RESULTS: Patients with T2DM and HFpEF had reduced LV radial peak systolic strain rate (PSSR), LV circumferential peak diastolic strain rate (PDSR), LA reservoir strain, global myocardial perfusion reserve index (MPRI), and increased LA booster strain compared to patients with T2DM without HFpEF (all P < 0.05). Furthermore, LV longitudinal PSSR, LA reservoir, and LA conduit strain were notably impaired in patients with T2DM without HFpEF compared to controls (all P < 0.05), but LV torsion, LV radial PSSR, and LA booster strain compensated for these alterations (all P < 0.05). Multivariate linear regression analysis demonstrated that LA reservoir and LA booster strain were independently associated with global MPRI (ß = 0.259, P < 0.001; ß = - 0.326, P < 0.001, respectively). Further, the difference in LA reservoir and LA booster strain between patients with T2DM with and without HFpEF was totally mediated by global MPRI. Global stress PI, LA booster, global rest PI, and global MPRI showed high accuracy in diagnosing HFpEF among patients with T2DM (areas under the curve [AUC]: 0.803, 0.790, 0.740, 0.740, respectively). CONCLUSIONS: Patients with T2DM and HFpEF exhibited significant LV systolic and diastolic deformation, decreased LA reservoir strain, severe impairment of myocardial perfusion, and elevated LA booster strain that is a compensatory response in HFpEF. Global MPRI was identified as an independent influencing factor on LA reservoir and LA booster strain. The difference in LA reservoir and LA booster strain between patients with T2DM with and without HFpEF was totally mediated by global MPRI, suggesting a possible mechanistic link between microcirculation impairment and cardiac dysfunction in diabetes. Myocardial perfusion and LA strain may prove valuable for diagnosing and managing HFpEF in the future.

Establishment of patient-derived organoids and a characterization based drug discovery platform for treatment of gastric cancer.

BACKGROUND: Gastric cancer (GC) encompasses many different histological and molecular subtypes. It is a major driver of cancer mortality because of poor survival and limited treatment options. Personalised medicine in the form of patient-derived organoids (PDOs) represents a promising approach for improving therapeutic outcomes. The goal of this study was to overcome the limitations of current models by ameliorating organoid cultivation. METHODS: Organoids derived from cancer tissue were evaluated by haematoxylin and eosin staining, immunohistochemistry, mRNA, and whole-exome sequencing. Three representative chemotherapy drugs, 5-fluorouracil, docetaxel, and oxaliplatin, were compared for their efficacy against different subtypes of gastric organoids by ATP assay and apoptosis staining. In addition, drug sensitivity screening results from two publicly available databases, the Genomics of Drug Sensitivity in Cancer and Cancer Cell Line Encyclopaedia, were pooled and applied to organoid lines. Once key targeting genes were confirmed, chemotherapy was used in combination with poly (ADP ribose) polymerase (PARP)-targeted therapy. RESULTS: We successfully constructed GC PDOs surgically resected from GC patient tissue. PDOs closely reflected the histopathological and genomic features of the corresponding primary tumours. Whole-exosome sequencing and mRNA analysis revealed that changes to the original tumour genome were maintained during long-term culture. The drugs caused divergent responses in intestinal, poorly differentiated intestinal, and diffuse gastric cancer organoids, which were confirmed in organoid lines. Poorly differentiated intestinal GC patients benefited from a combination of 5-fluorouracil and veliparib. CONCLUSION: The present study demonstrates that combining chemotherapy with PARP targeting may improve the treatment of chemotherapy-resistant tumours.