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1.
Article in English | MEDLINE | ID: mdl-39255122

ABSTRACT

Steering is a fundamental task in interactive Virtual Reality (VR) systems. Prior work has demonstrated that movement direction can significantly influence user behavior in the steering task, and different interactive environments (VEs) can lead to various behavioral patterns, such as tablets and PCs. However, its impact on VR environments remains unexplored. Given the widespread use of steering tasks in VEs, including menu adjustment and object manipulation, this work seeks to understand and model the directional effect with a focus on barehand interaction, which is typical in VEs. This paper presents the results of two studies. The first study was conducted to collect behavioral data with four categories: movement time, average movement speed, success rate, and reenter times. According to the results, we examined the effect of movement direction and built the SθModel. We then empirically evaluated the model through the data collected from the first study. The results proved that our proposed model achieved the best performance across all the metrics (r 2 > 0.95), with more than 15% improvement over the original Steering Law in terms of prediction accuracy. Next, we further validated the SθModel by another study with the change of device and steering direction. Consistent with previous assessments, the model continues to exhibit optimal performance in both predicting movement time and speed. Finally, based on the results, we formulated design recommendations for steering tasks in VEs to enhance user experience and interaction efficiency.

2.
Article in English | MEDLINE | ID: mdl-39255157

ABSTRACT

Authentication in digital security relies heavily on text-based passwords, even with other available methods like biometrics and graphical passwords. While virtual reality (VR) keyboards are typically invisible to onlookers, the presence of inconspicuous sensors, including accelerometers, gyroscopes, and barometers, poses a potential risk of unauthorized observation and recording. Traditional defense shoulder-surfing attack methods typically involve breaking apart the Qwerty layout, which destroys the user's inherent familiarity with the layout. This research addresses the need for secure password entry in VR environments while retaining the Qwerty layout. We explore three keyboard-related position alteration strategies to ensure security while mitigating the decline in user experience. These strategies involve moving the entire keyboard, cursor, and keys. Our theoretical study assesses the effectiveness of these strategies against shoulder-surfing attacks. Two user studies, employing ray-based and position-based text entry methods, respectively, evaluate the practical effectiveness of the three strategies in resisting shoulder-surfing attacks, as well as their impact on typing performance and user experience. Our findings demonstrate that the three strategies achieve shoulder-surfing attack resistance comparable to a random layout keyboard. Moreover, compared to a random layout, the two strategies involving the movement of the entire keyboard and the repositioning of keys support faster entry rates and enhanced user experience.

3.
Article in English | MEDLINE | ID: mdl-39255139

ABSTRACT

The use of Virtual Reality (VR) technology, especially in medical rehabilitation, has expanded to include tactile cues along with visual stimuli. For patients with upper limb hemiplegia, tangible handles with haptic stimuli could improve their ability to perform daily activities. Traditional VR controllers are unsuitable for patient rehabilitation in VR, necessitating the design of specialized tangible handles with integrated tracking devices. Besides, matching tactile stimulation with corresponding virtual visuals could strengthen users' embodiment (i.e., owning and controlling virtual bodies) in VR, which is crucial for patients' training with virtual hands. Haptic stimuli have been shown to amplify the embodiment in VR, whereas the effect of partial tactile stimulation from tangible handles on embodiment remains to be clarified. This research, including three experiments, aims to investigate how partial tactile feedback of tangible handles impacts users' embodiment, and we proposed a design concept called TouchMark for partial tactile stimuli that could help users quickly connect the physical and virtual worlds. To evaluate users' tactile and comfort perceptions when grasping tangible handles in a non-VR setting, various handles with three partial tactile factors were manipulated in Study 1. In Study 2, we explored the effects of partial feedback using three forms of TouchMark on the embodiment of healthy users in VR, with various tangible handles, while Study 3 focused on similar investigations with patients. These handles were utilized to complete virtual food preparation tasks. The tactile and comfort perceptions of tangible handles and users' embodiment were evaluated in this research using questionnaires and interviews. The results indicate that TouchMark with haptic line and ring forms over no stimulation would significantly enhance users' embodiment, especially for patients. The low-cost and innovative TouchMark approach may assist users, particularly those with limited VR experience, in achieving the embodiment and enhancing their virtual interactive experience.

4.
Nat Commun ; 15(1): 7652, 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39227563

ABSTRACT

P2X receptors, a subfamily of ligand-gated ion channels activated by extracellular ATP, are implicated in various physiopathological processes, including inflammation, pain perception, and immune and respiratory regulations. Structural determinations using crystallography and cryo-EM have revealed that the extracellular three-dimensional architectures of different P2X subtypes across various species are remarkably identical, greatly advancing our understanding of P2X activation mechanisms. However, structural studies yield paradoxical architectures of the intracellular domain (ICD) of different subtypes (e.g., P2X3 and P2X7) at the apo state, and the role of the ICD in P2X functional regulation remains unclear. Here, we propose that the P2X3 receptor's ICD has an apo state conformation similar to the open state but with a less tense architecture, containing allosteric sites that influence P2X3's physiological and pathological roles. Using covalent occupancy, engineered disulfide bonds and voltage-clamp fluorometry, we suggested that the ICD can undergo coordinated motions with the transmembrane domain of P2X3, thereby facilitating channel activation. Additionally, we identified a novel P2X3 enhancer, PSFL77, and uncovered its potential allosteric site located in the 1α3ß domain of the ICD. PSFL77 modulated pain perception in P2rx3+/+, but not in P2rx3-/-, mice, indicating that the 1α3ß, a "tunable" region implicated in the regulation of P2X3 functions. Thus, when P2X3 is in its apo state, its ICD architecture is fairly ordered rather than an unstructured outward folding, enabling allosteric modulation of the signaling of P2X3 receptors.


Subject(s)
Allosteric Site , Protein Domains , Receptors, Purinergic P2X3 , Animals , Receptors, Purinergic P2X3/metabolism , Receptors, Purinergic P2X3/chemistry , Receptors, Purinergic P2X3/genetics , Humans , Mice , HEK293 Cells , Adenosine Triphosphate/metabolism , Male , Mice, Inbred C57BL , Allosteric Regulation
5.
J Thorac Dis ; 16(8): 5274-5284, 2024 Aug 31.
Article in English | MEDLINE | ID: mdl-39268132

ABSTRACT

Background: There is a shortage of reliable predictive models to provide valuable prognostic information for early esophageal squamous cell carcinoma (ESCC) without lymph node metastasis (LNM). We aimed to develop and validate a nomogram using the prognostic factors in T1N0 ESCC patients. Methods: Patients with pathological T1N0 ESCC who underwent esophagectomy between 2014 and 2021 at three institutes were reviewed. The prognostic factors were evaluated by Cox proportional hazards model and a nomogram was developed. Patients were divided into high- and low-risk groups based on cut-off value of total points in the nomogram. Overall survival (OS) was estimated by the Kaplan-Meier method and compared using the log-rank test. Results: A total of 275 patients were included and split into training (n=180) and external validation (n=95) cohorts. In the training cohort, multivariable analysis showed that the surgical approach, T1 substage, and carcinoembryonic antigen (CEA) level were independent prognostic factors. The developed nomogram had relatively high performance, with the area under the receiver operating characteristic (ROC) curve (AUC) of 0.783, 0.711 and 0.612 for 1-, 3-, and 5-year OS, respectively. The calibration curves showed that the predicted probability was in good agreement with the actual probability. Forty-seven was determined as cut-off value of total points. High-risk group (n=148) showed a significant poor OS than low-risk group (n=127) (P<0.001). Conclusions: Left surgical approach, stage T1b, and higher CEA were associated with poorer prognosis in T1N0 ESCC patients. The nomogram demonstrated a good performance to predict the individual survival.

6.
Article in English | MEDLINE | ID: mdl-39255119

ABSTRACT

We propose and study a novel cross-reality environment that seamlessly integrates a monoscopic 2D surface (an interactive screen with touch and pen input) with a stereoscopic 3D space (an augmented reality HMD) to jointly host spatial data visualizations. This innovative approach combines the best of two conventional methods of displaying and manipulating spatial 3D data, enabling users to fluidly explore diverse visual forms using tailored interaction techniques. Providing such effective 3D data exploration techniques is pivotal for conveying its intricate spatial structures-often at multiple spatial or semantic scales-across various application domains and requiring diverse visual representations for effective visualization. To understand user reactions to our new environment, we began with an elicitation user study, in which we captured their responses and interactions. We observed that users adapted their interaction approaches based on perceived visual representations, with natural transitions in spatial awareness and actions while navigating across the physical surface. Our findings then informed the development of a design space for spatial data exploration in cross-reality. We thus developed cross-reality environments tailored to three distinct domains: for 3D molecular structure data, for 3D point cloud data, and for 3D anatomical data. In particular, we designed interaction techniques that account for the inherent features of interactions in both spaces, facilitating various forms of interaction, including mid-air gestures, touch interactions, pen interactions, and combinations thereof, to enhance the users' sense of presence and engagement. We assessed the usability of our environment with biologists, focusing on its use for domain research. In addition, we evaluated our interaction transition designs with virtual and mixed-reality experts to gather further insights. As a result, we provide our design suggestions for the cross-reality environment, emphasizing the interaction with diverse visual representations and seamless interaction transitions between 2D and 3D spaces.

7.
Shock ; 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39158573

ABSTRACT

ABSTRACT: Restoration of mesenteric lymphatic microcirculation is crucial for alleviating severe hemorrhagic shock-induced death. Exercise preconditioning (EP) enhances adaptability and resistance to injury and disease. The mitochondria-associated endoplasmic reticulum membrane (MAM) plays a crucial role in the energy and information exchange between the two organelles. Therefore, we hypothesized that EP ameliorates mesenteric lymphatic contractility through MAM in rats following hemorrhagic shock, aiming to confirm that EP enhances resistance to hemorrhagic shock and further popularizes the idea that exercise is beneficial for health. To test this hypothesis, we observed the effects of EP for four weeks on survival time and mesenteric lymphatic contractility in conscious rats following hemorrhagic shock, and further explored the effects of MAM agonists and inhibitors. The results showed that EP prolonged the survival time and improved the mesenteric lymphatic contractility and reactivity in vivo and in vitro in rats underwent hemorrhagic shock, ameliorated the MAM ultrastructure in lymphatic smooth muscle cells (LSMCs) and reduced the voltage-dependent anion channel 1 (VDAC1, a vital protein of MAM) and IP3R1 expressions in mesenteric lymphatic tissue. Importantly, treatment with 2-APB (IP3R1 inhibitor) or VBIT-12 (VDAC1 inhibitor) prolonged the survival time, improved mesenteric lymphatic contractility in vivo, ameliorated the MAM ultrastructure injury, and decreased the IP3R1 or VDAC1 expressions in LSMCs in rats following hemorrhagic shock. In contrast, the administration of drinking water containing CdCl2 (IP3R1 activator) abolished the beneficial effect of EP on hemorrhagic shock. Taken together, the protective effect of EP on lymphatic contractility following hemorrhagic shock was achieved by improving MAM in LSMCs.

8.
Inorg Chem ; 63(32): 15090-15097, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39087570

ABSTRACT

The conversion of CO2 into useful chemicals via photocatalysts is a promising strategy for resolving the environmental problems caused by the addition of CO2. Herein, a series of composite photocatalysts MOP@TpPa-CH3 based on MOP-NH2 and TpPa-CH3 through covalent bridging have been prepared via a facile room-temperature evaporation method and employed for photocatalytic CO2 reduction. The photocatalytic performances of MOP@TpPa-CH3 are greater than those of TpPa-CH3 and MOP-NH2, where the CO generation rate of MOP@TpPa-CH3 under 10% CO2 still reaches 119.25 µmol g-1 h-1, which is 2.18 times higher than that under pure CO2 (54.74 µmol g-1 h-1). To investigate the structural factors affecting the photocatalytic activity, MOP@TBPa-CH3 without C═O groups is synthesized, and the photoreduction performance is also evaluated. The controlling experimental results demonstrate that the excellent photoreduction CO2 performance of MOP@TpPa-CH3 in a 10% CO2 atmosphere is due to the presence of C═O groups in TpPa-CH3. This work offers a new design and construction strategy for novel MOP@COF composites.

9.
Article in English | MEDLINE | ID: mdl-39162795

ABSTRACT

Dysregulation of lipid metabolism plays a key role in the onset and progression of CKD, and a thorough understanding of its regulatory mechanisms is essential for the development of effective treatments. In recent years, an increasing number of studies have focused on the pharmacological activities of natural products and their application in the treatment of chronic diseases. Natural products, including plant extracts and bioactive compounds, have been shown to exert anti-inflammatory, antioxidant, antifibrosis, and anti-apoptotic effects through various signaling pathways in the treatment of CKD. Many natural products have been shown to target dysregulated lipid metabolism through various signaling pathways. This review summarizes the key regulatory factors and signaling pathways involved in the dysregulation of lipid metabolism in chronic kidney disease (CKD), highlighting their importance as potential therapeutic targets. Recently published research on the potential therapeutic benefits of natural products for the treatment of CKD was described. These studies have revealed the multi-target role of natural products in the regulation of lipid metabolism. Natural products show great potential in targeting lipid metabolism-related pathways, offering a novel research direction for the treatment of CKD while providing a scientific basis and experimental support for the development of new treatment strategies.

10.
Article in English | MEDLINE | ID: mdl-39208039

ABSTRACT

Prior work has shown that frame rate significantly influences user behavior in fast-response tasks in 2D and 3D contexts. However, its impact on a steering task, which involves navigating an object along a path from the start to the end, remains relatively unexplored, especially in the context of virtual reality (VR). This task is considered a typical non-fast-response activity, as it does not demand rapid reactions within a limited time frame. Our work aims to understand and model users' steering behavior and predict movement time with different task complexities and frame rates in VR environments. We first conducted a user study to collect user behavior in a steering task with four factors: frame rate, path length, width, and radius of curvature. Based on the results, we then quantified the effects of frame rate and built two predictive models. Our models exhibited the best fit ([Formula: see text]) and over 17% improvement in prediction accuracy for movement time compared to existing models. Our models' robustness was further validated by applying them to predict steering performance with different VR tasks and frame rates. The two models keep the best predictability for both movement time and speed.

11.
Surg Infect (Larchmt) ; 25(6): 444-451, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38957995

ABSTRACT

Background: The objective of this study was to investigate the association between pre-operative body mass index (BMI) and surgical infection in perihilar cholangiocarcinoma (pCCA) patients treated with curative resection. Methods: Consecutive pCCA patients were enrolled from four tertiary hospitals between 2008 and 2022. According to pre-operative BMI, the patients were divided into three groups: low BMI (≤18.4 kg/m2), normal BMI (18.5-24.9 kg/m2), and high BMI (≥25.0 kg/m2). The incidence of surgical infection among the three groups was compared. Multivariable logistic regression models were used to determine the independent risk factors associated with surgical infection. Results: A total of 371 patients were enrolled, including 283 patients (76.3%) in the normal BMI group, 30 patients (8.1%) in the low BMI group, and 58 patients (15.6%) in the high BMI group. The incidence of surgical infection was significantly higher in the patients in the low BMI and high BMI groups than in the normal BMI group. The multivariable logistic regression model showed that low BMI and high BMI were independently associated with the occurrence of surgical infection. Conclusions: The pCCA patients with a normal BMI treated with curative resection could have a lower risk of surgical infection than pCCA patients with an abnormal BMI.


Subject(s)
Body Mass Index , Klatskin Tumor , Surgical Wound Infection , Humans , Male , Female , Middle Aged , Aged , Surgical Wound Infection/epidemiology , Risk Factors , Klatskin Tumor/surgery , Klatskin Tumor/complications , Incidence , Bile Duct Neoplasms/surgery , Bile Duct Neoplasms/complications , Bile Duct Neoplasms/epidemiology , Retrospective Studies , Adult , Preoperative Period
12.
Games Health J ; 13(4): 297-304, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38985574

ABSTRACT

Objective: Following the initial measures taken to manage the repercussions of the COVID-19 pandemic, mental health conditions have become a critical concern. Mental health has become a foremost priority not only for health care providers but also for many other organizations, such as educational institutions, companies, and government agencies. A significant proportion of the Australian population having experienced mental disorders highlights the need for effective interventions. Those with pre-existing mental health issues experienced particularly pronounced effects. Among these challenges, advancements in technology offer new possibilities for mental health support. Videogames have shown effectiveness in mitigating symptoms of depression. Previous research has shown that game interface preferences correlate with players' emotional responses. This study aims to use MoodJumper, a game we designed, developed, and evaluated to examine the choice of game preferences in individuals with depressive symptoms. Materials and Methods: A pilot study was carried out after obtaining the Human Ethics committee's approval (n = 20). The participants were asked to fill out a Patient Health Questionnaire-9 (PHQ-9) questionnaire. They then played with the MoodJumper game for 20-30 minutes. Upon completing the game session, they were asked to fill out a questionnaire regarding their experience. Results: The results indicate a nonsignificant correlation between music preference, the direction of movement, and depressive symptoms meaning no significant relationship was found between depressive symptoms and chosen settings. However, a significant negative correlation was found between decision-making ability regarding game preferences and Patient Health Questionnaire-9 scores showing the difficulty of choosing preferred settings when having depressive symptoms. Conclusion: This contribution paves the way for designing and evaluating more impactful game experiences for individuals with mental health challenges.


Subject(s)
COVID-19 , Depression , Video Games , Humans , Pilot Projects , Video Games/psychology , Video Games/statistics & numerical data , Depression/psychology , Male , Female , Adult , COVID-19/psychology , Australia , Surveys and Questionnaires , SARS-CoV-2 , Middle Aged
13.
Article in English | MEDLINE | ID: mdl-39052867

ABSTRACT

Magnesium (Mg) deficiency is associated with increased risk and malignancy in colorectal cancer (CRC), yet the underlying mechanisms remain elusive. Here, we used genomic, proteomic, and phosphoproteomic data to elucidate the impact of Mg deficiency on CRC. Genomic analysis identified 160 genes with higher mutation frequencies in Low-Mg tumors, including key driver genes such as KMT2C and ERBB3. Unexpectedly, initiation driver genes of CRC, such as TP53 and APC, displayed higher mutation frequencies in High-Mg tumors. Additionally, proteomic and phosphoproteomic data indicated that low Mg content in tumors may activate epithelial-mesenchymal transition (EMT) by modulating inflammation or remodeling the phosphoproteome of cancer cells. Notably, we observed a negative correlation between the phosphorylation of DBN1 at S142 (DBN1S142p) and Mg content. A mutation in S142 to D (DBN1S142D) mimicking DBN1S142p upregulated MMP2 and enhanced cell migration, while treatment with MgCl2 reduced DBN1S142p, thereby reversing this phenotype. Mechanistically, Mg2+ attenuated the DBN1-ACTN4 interaction by decreasing DBN1S142p, which in turn enhanced the binding of ACTN4 to F-actin and promoted F-actin polymerization, ultimately reducing MMP2 expression. These findings shed new light on the crucial role of Mg deficiency in CRC progression and suggest that Mg supplementation may be a promising preventive and therapeutic strategy for CRC.

14.
J Affect Disord ; 362: 308-316, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38971193

ABSTRACT

BACKGROUND: The bidirectional relationships between metabolic syndrome (MetS) and major depressive disorder (MDD) were discovered, but the influencing factors of the comorbidity were barely investigated. We aimed to fully explore the factors and their associations with MetS in MDD patients. METHODS: The data were retrieved from the electronic medical records of a tertiary psychiatric hospital in Beijing from 2016 to 2021. The influencing factors were firstly explored by univariate analysis and multivariate logistic regressions. The propensity score matching was used to reduce the selection bias of participants. Then, the Bayesian networks (BNs) with hill-climbing algorithm and maximum likelihood estimation were preformed to explore the relationships between influencing factors with MetS in MDD patients. RESULTS: Totally, 4126 eligible subjects were included in the data analysis. The proportion rate of MetS was 32.6 % (95 % CI: 31.2 %-34.1 %). The multivariate logistic regression suggested that recurrent depression, uric acid, duration of depression, marriage, education, number of hospitalizations were significantly associated with MetS. In the BNs, number of hospitalizations and uric acid were directly connected with MetS. Recurrent depression and family history psychiatric diseases were indirectly connected with MetS. The conditional probability of MetS in MDD patients with family history of psychiatric diseases, recurrent depression and two or more times of hospitalizations was 37.6 %. CONCLUSION: Using the BNs, we found that number of hospitalizations, recurrent depression and family history of psychiatric diseases contributed to the probability of MetS, which could help to make health strategies for specific MDD patients.


Subject(s)
Bayes Theorem , Comorbidity , Depressive Disorder, Major , Metabolic Syndrome , Humans , Depressive Disorder, Major/epidemiology , Metabolic Syndrome/epidemiology , Female , Male , Middle Aged , Adult , Risk Factors , China/epidemiology , Logistic Models , Hospitalization/statistics & numerical data , Uric Acid/blood , Propensity Score
15.
Angew Chem Int Ed Engl ; 63(40): e202410722, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38965047

ABSTRACT

In this work, a noncoplanar terphenyl served as a building block to synthesize a novel 3,3'-substituted bipyridyl ligand (L1) which further reacted with binuclear half-sandwich units A/B, giving rise to two aesthetic 41 metalla-knots in high yields via a coordination-driven self-assembly strategy. Furthermore, given the inherent compactness of the 41 metalla-knots, it creates favorable conditions for the emergence of steric repulsion. We focused on progressively introducing nitrogen atoms featuring a lone pair of electrons (LPEs) into ligand L1 to manipulate the balance of H⋅⋅⋅H/LPEs⋅⋅⋅LPEs steric repulsion during the assembly process, ultimately achieving controlled assembly from 41 metalla-knots to the pseudo-Solomon link and then to molecular tweezer-like assembly facilitated by stacking interactions. All the assemblies were well characterized by solution-state NMR techniques, ESI-TOF/MS, and single-crystal X-ray diffraction. The evolutionary process of the topological architectures is equivalent to visualizing the synergistic effect of steric hindrance and stacking interactions on structural assembly, providing a new avenue for achieving the controlled synthesis of different topologies.

16.
Surgery ; 176(3): 730-738, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38902127

ABSTRACT

BACKGROUND: Lymph node metastasis is significantly associated with a worse prognosis in patients with localized early-stage esophageal squamous cell carcinoma. This study aimed to explore the prognostic factors and develop a nomogram for predicting survival in patients with pathologic T1-2N+ esophageal squamous cell carcinoma. METHODS: Between 2014 and 2022, patients with pT1-2N+ esophageal squamous cell carcinoma who underwent esophagectomy with lymphadenectomy at 2 institutes were reviewed and assigned to training and external validation cohorts. Independent prognostic factors were identified via univariate and multivariate Cox regression analyses. The nomogram model was developed and evaluated by the area under the receiver operating characteristic curve and calibration curve. RESULTS: In total, 268 patients with a median age of 65 years (range, 40-82) were included and assigned to training (n = 190) and external validation (n = 78) cohorts. The Cox proportional hazards model demonstrated that body mass index (P = .031), surgical approach (P < .001), T stage (P = .015), and Clavien-Dindo classification (P < .001) were independent prognostic factors in the training cohort. The nomogram showed good discrimination, with an area under the receiver operating characteristic curve for 1-year, 3-year, and 5-year of 0.810, 0.789, and 0.809 in the training cohort and 0.782, 0.679, and 0.698 in the validation cohort. The calibration curve showed that the predicted survival probability was in good agreement with the actual survival probability. CONCLUSION: Lower body mass index, left surgical approach, T2 stage, and Clavien-Dindo classification grade III to V were related to worse prognosis in patients with pT1-T2N+ esophageal squamous cell carcinoma. The developed nomogram may predict individual survival accurately.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Esophagectomy , Neoplasm Staging , Nomograms , Humans , Middle Aged , Male , Female , Retrospective Studies , Aged , Esophageal Squamous Cell Carcinoma/surgery , Esophageal Squamous Cell Carcinoma/mortality , Esophageal Squamous Cell Carcinoma/pathology , Esophageal Neoplasms/mortality , Esophageal Neoplasms/pathology , Esophageal Neoplasms/surgery , Prognosis , Adult , Aged, 80 and over , Lymphatic Metastasis , Lymph Node Excision , ROC Curve , Proportional Hazards Models
17.
Immunology ; 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38934051

ABSTRACT

Maintaining intracellular redox balance is essential for the survival, antibody secretion, and mucosal immune homeostasis of immunoglobulin A (IgA) antibody-secreting cells (ASCs). However, the relationship between mitochondrial metabolic enzymes and the redox balance in ASCs has yet to be comprehensively studied. Our study unveils the pivotal role of mitochondrial enzyme PCK2 in regulating ASCs' redox balance and intestinal homeostasis. We discover that PCK2 loss, whether globally or in B cells, exacerbates dextran sodium sulphate (DSS)-induced colitis due to increased IgA ASC cell death and diminished antibody production. Mechanistically, the absence of PCK2 diverts glutamine into the TCA cycle, leading to heightened TCA flux and excessive mitochondrial reactive oxygen species (mtROS) production. In addition, PCK2 loss reduces glutamine availability for glutathione (GSH) synthesis, resulting in a decrease of total glutathione level. The elevated mtROS and reduced GSH expose ASCs to overwhelming oxidative stress, culminating in cell apoptosis. Crucially, we found that the mitochondria-targeted antioxidant Mitoquinone (Mito-Q) can mitigate the detrimental effects of PCK2 deficiency in IgA ASCs, thereby alleviating colitis in mice. Our findings highlight PCK2 as a key player in IgA ASC survival and provide a potential new target for colitis treatment.

18.
Proc Natl Acad Sci U S A ; 121(27): e2407570121, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38941275

ABSTRACT

Although mechanically interlocked molecules (MIMs) display unique properties and functions associated with their intricate connectivity, limited assembly strategies are available for their synthesis. Herein, we presented a synergistic assembly strategy based on coordination and noncovalent interactions (π-π stacking and CH⋯π interactions) to selectively synthesize molecular closed three-link chains ([Formula: see text] links), highly entangled figure-eight knots ([Formula: see text] knots), trefoil knot ([Formula: see text] knot), and Borromean ring ([Formula: see text] link). [Formula: see text] links can be created by the strategic assembly of nonlinear multicurved ligands incorporating a furan or phenyl group with the long binuclear half-sandwich organometallic Cp*RhIII (Cp* = η5-pentamethylcyclopentadienyl) clip. However, utilizing much shorter binuclear Cp*RhIII units for union with the 2,6-naphthyl-containing ligand led to a [Formula: see text] knot because of the increased π-π stacking interactions between four consecutive stacked layers and CH⋯π interactions. Weakening such π-π stacking interactions resulted in a [Formula: see text] knot. The universality of this synergistic assembly strategy for building [Formula: see text] knots was verified by utilizing a 1,5-naphthyl-containing ligand. Quantitative conversion between the [Formula: see text] knot and the simple macrocycle species was accomplished by adjusting the concentrations monitored by NMR spectroscopy and electrospray ionization mass spectrometry (ESI-MS). Furthermore, increasing the stiff π-conjugated area of the binuclear unit afforded molecular Borromean ring, and this topology is a topological isomer of the [Formula: see text] link. These artificial metalla-links and metalla-knots were confirmed by single-crystal X-ray diffraction, NMR and ESI-MS. The results offer a potent strategy for building higher-order MIMs and emphasize the critical role that noncovalent interactions play in creating sophisticated topologies.

19.
Sci China Life Sci ; 67(6): 1089-1105, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38842635

ABSTRACT

Histone H3 Lys36 (H3K36) methylation and its associated modifiers are crucial for DNA double-strand break (DSB) repair, but the mechanism governing whether and how different H3K36 methylation forms impact repair pathways is unclear. Here, we unveil the distinct roles of H3K36 dimethylation (H3K36me2) and H3K36 trimethylation (H3K36me3) in DSB repair via non-homologous end joining (NHEJ) or homologous recombination (HR). Yeast cells lacking H3K36me2 or H3K36me3 exhibit reduced NHEJ or HR efficiency. yKu70 and Rfa1 bind H3K36me2- or H3K36me3-modified peptides and chromatin, respectively. Disrupting these interactions impairs yKu70 and Rfa1 recruitment to damaged H3K36me2- or H3K36me3-rich loci, increasing DNA damage sensitivity and decreasing repair efficiency. Conversely, H3K36me2-enriched intergenic regions and H3K36me3-enriched gene bodies independently recruit yKu70 or Rfa1 under DSB stress. Importantly, human KU70 and RPA1, the homologs of yKu70 and Rfa1, exclusively associate with H3K36me2 and H3K36me3 in a conserved manner. These findings provide valuable insights into how H3K36me2 and H3K36me3 regulate distinct DSB repair pathways, highlighting H3K36 methylation as a critical element in the choice of DSB repair pathway.


Subject(s)
DNA Breaks, Double-Stranded , DNA End-Joining Repair , Histones , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Histones/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Humans , Methylation , Ku Autoantigen/metabolism , Ku Autoantigen/genetics , Replication Protein A/metabolism , Replication Protein A/genetics , Homologous Recombination , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/genetics , DNA Repair , Chromatin/metabolism , Chromatin/genetics
20.
Article in English | MEDLINE | ID: mdl-38824095

ABSTRACT

BACKGROUND: In patients with hilar cholangiocarcinoma (HCCA), radical resection can be achieved by resection and reconstruction of the vasculature. However, whether vascular reconstruction (VR) improves long-term and short-term prognosis has not been demonstrated comprehensively. METHODS: This was a retrospective multicenter study of patients who received surgery for HCCA with or without VR. Variables associated with overall survival (OS) and recurrence-free survival (RFS) were identified based on Cox regression. Kaplan-Meier curves were used to explore the impact of VR. Restricted mean survival time (RMST) was used for comparisons of short-term survival between the groups. Patients' intraoperative and postoperative characteristics were compared. RESULTS: Totally 447 patients were enrolled. We divided these patients into 3 groups: VR with radical resections (n = 84); non-VR radical resections (n = 309) and non-radical resection (we pooled VR-nonradical and non-VR nonradical together, n = 54). Cox regression revealed that carbohydrate antigen 242 (CA242), vascular invasion, lymph node metastasis and poor differentiation were independent risk factors for OS and RFS. There was no significant difference of RMST between the VR and non-VR radical groups within 12 months after surgery (10.18 vs. 10.76 mon, P = 0.179), although the 5-year OS (P < 0.001) and RFS (P < 0.001) were worse in the VR radical group. The incidences of most complications were not significantly different, but those of bile leakage (P < 0.001) and postoperative infection (P = 0.009) were higher in the VR radical group than in the non-VR radical group. Additionally, the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) up to 7 days after surgery tended to decrease in all groups. There was no significant difference in the incidence of postoperative liver failure between the VR and non-VR radical groups. CONCLUSIONS: Radical resection can be achieved with VR to improve the survival rate without worsening short-term survival compared with resection with non-VR. After adequate assessment of the patient's general condition, VR can be considered in the resection.

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