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1.
Transplantation ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38946027

ABSTRACT

BACKGROUND: Antibody-mediated rejection (AMR) is a major cause of renal allograft dysfunction and loss. Targeting B cells and/or donor-specific antibody removal using plasma exchange and anti-CD20 antibodies are increasingly used in clinical practice, but the efficacy remains limited. Recent studies suggest that targeting purinergic P2X7 receptor/ATP axis can have profound immune regulatory effects in transplant models, but the mechanisms involved remain incompletely defined. METHODS: Purified B cells were isolated from the spleen of Balb/C mice and cultured with oxidized ATP at different concentrations. Proliferation and differentiation of B cells were examined. Effects of oxidized ATP were examined in a presensitized animal model where kidney allograft rejection mimics aspects of clinical AMR. Histopathology was assessed at the time of rejection or on day 5 after kidney transplantation. Infiltrating immune cells in renal allografts were detected by flow cytometry. RESULTS: Oxidized ATP inhibited B-cell activation and proliferation in vitro, significantly attenuated histological signs of graft injury and prolonged kidney allograft survival. Mechanistically, oxidized ATP inhibited antibody secretion by activated B cells in response to lipopolysaccharide stimulation and markedly suppressed the production of donor-specific antibody in kidney allograft recipients. Oxidized ATP also reduced graft infiltration by other inflammatory cells. CONCLUSIONS: These findings provide evidence for the involvement of the purinergic P2X7 receptor pathway in AMR and suggest that targeting this pathways may have important clinical implications.

2.
Cell Death Dis ; 15(6): 434, 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38898023

ABSTRACT

The interaction between glioblastoma cells and glioblastoma-associated macrophages (GAMs) influences the immunosuppressive tumor microenvironment, leading to ineffective immunotherapies. We hypothesized that disrupting the communication between tumors and macrophages would enhance the efficacy of immunotherapies. Transcriptomic analysis of recurrent glioblastoma specimens indicated an enhanced neuroinflammatory pathway, with CXCL12 emerging as the top-ranked gene in secretory molecules. Single-cell transcriptome profiling of naïve glioblastoma specimens revealed CXCL12 expression in tumor and myeloid clusters. An analysis of public glioblastoma datasets has confirmed the association of CXCL12 with disease and PD-L1 expression. In vitro studies have demonstrated that exogenous CXCL12 induces pro-tumorigenic characteristics in macrophage-like cells and upregulated PD-L1 expression through NF-κB signaling. We identified CXCR7, an atypical receptor for CXCL12 predominantly present in tumor cells, as a negative regulator of CXCL12 expression by interfering with extracellular signal-regulated kinase activation. CXCR7 knockdown in a glioblastoma mouse model resulted in worse survival outcomes, increased PD-L1 expression in GAMs, and reduced CD8+ T-cell infiltration compared with the control group. Ex vivo T-cell experiments demonstrated enhanced cytotoxicity against tumor cells with a selective CXCR7 agonist, VUF11207, reversing GAM-induced immunosuppression in a glioblastoma cell-macrophage-T-cell co-culture system. Notably, VUF11207 prolonged survival and potentiated the anti-tumor effect of the anti-PD-L1 antibody in glioblastoma-bearing mice. This effect was mitigated by an anti-CD8ß antibody, indicating the synergistic effect of VUF11207. In conclusion, CXCL12 conferred immunosuppression mediated by pro-tumorigenic and PD-L1-expressing GAMs in glioblastoma. Targeted activation of glioblastoma-derived CXCR7 inhibits CXCL12, thereby eliciting anti-tumor immunity and enhancing the efficacy of anti-PD-L1 antibodies.


Subject(s)
B7-H1 Antigen , Chemokine CXCL12 , Glioblastoma , Receptors, CXCR , Glioblastoma/pathology , Glioblastoma/immunology , Glioblastoma/genetics , Glioblastoma/metabolism , Humans , Animals , Receptors, CXCR/metabolism , Receptors, CXCR/genetics , Chemokine CXCL12/metabolism , Mice , B7-H1 Antigen/metabolism , Cell Line, Tumor , Tumor Microenvironment , Brain Neoplasms/pathology , Brain Neoplasms/immunology , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Signal Transduction/drug effects
3.
Chem Commun (Camb) ; 60(46): 5948-5951, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38764410

ABSTRACT

Structurally symmetric dyes using functionalized fluorenes and benzotriazole as the main building moieties have been synthesized and found to exhibit efficient dual-state emission (DSE) and interesting two-wavelength or dual amplified spontaneous emission (dual-ASE) behaviors in the solution phase, which may benefit the development of organic gain materials with dual-wavelength amplification.

4.
RSC Adv ; 14(22): 15358-15364, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38741959

ABSTRACT

Functional separators modified by transition metal compounds have been proven to be effective in suppressing the shuttle effect of polysulfides and accelerating sluggish electrode dynamics in lithium-sulfur batteries (LSBs). However, the behaviors of heterojunctions composed of transition metals and their compounds in LSBs are still rarely studied. Herein, we report a novel Ni-CoSe2 heterostructure coated with nitrogen-doped carbon. Compared to homogeneous cobalt diselenide, it exhibits much stronger adsorption and catalytic conversion abilities towards polysulfides. With the modified separators, the lithium-sulfur batteries exhibit significantly improved capacity retention and reduced polarization during cycling.

6.
Eur J Clin Pharmacol ; 80(8): 1219-1227, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38691139

ABSTRACT

OBJECTIVES: To describe the pharmacokinetic (PK) characteristics of nirmatrelvir/ritonavir in renal transplant recipients and explore the potential factors that related to the PK variance of nirmatrelvir/ritonavir and its interaction with calcineurin inhibitor (CNI). METHODS: Renal transplant recipients treated with CNI and nirmatrelvir/ritonavir were prospectively enrolled. Steady-state plasma concentrations of nirmatrelvir/ritonavir were determined by high-performance liquid chromatography-tandem mass spectrometry, and the PK parameters were calculated using non-compartmental analysis. Spearman correlation analysis was used for exploring influencing factors. RESULTS: A total of eight recipients were enrolled; for nirmatrelvir and ritonavir, AUC/dose was 0.24179 ± 0.14495 and 0.06196 ± 0.03767 µg·h·mL-1·mg-1. Red blood cell (RBC), hematocrit (Ht), hemoglobins (Hb), and creatinine clearance (Ccr) were negatively correlated with AUC/dose of nirmatrelvir, while Ccr, CYP3A5 genotype, and CYP3A4 genotype were related to the AUC/dose of ritonavir. Ccr was negatively correlated with the C0/dose of tacrolimus (TAC) after termination of nirmatrelvir/ritonavir (rs = -0.943, p = 0.008). CONCLUSIONS: The PK characteristics of nirmatrelvir/ritonavir vary greatly among renal transplant recipients. Factors including Ccr and CYP3A5 genotype were related to the in vivo exposure of nirmatrelvir/ritonavir. During the whole process before and after nirmatrelvir/ritonavir therapy, it is recommended to adjust the CNI basing on renal function to avoid CNI toxicity exposure.


Subject(s)
Calcineurin Inhibitors , Drug Interactions , Kidney Transplantation , Ritonavir , Humans , Ritonavir/pharmacokinetics , Ritonavir/pharmacology , Male , Calcineurin Inhibitors/pharmacokinetics , Calcineurin Inhibitors/pharmacology , Calcineurin Inhibitors/administration & dosage , Female , Middle Aged , Adult , Cytochrome P-450 CYP3A/metabolism , Cytochrome P-450 CYP3A/genetics , Immunosuppressive Agents/pharmacokinetics , Immunosuppressive Agents/administration & dosage , Prospective Studies , Tacrolimus/pharmacokinetics , Tacrolimus/administration & dosage , Tacrolimus/pharmacology , Genotype , Area Under Curve , Transplant Recipients
7.
Transplantation ; 108(8): 1802-1811, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38499506

ABSTRACT

BACKGROUND: Co-infection of JC polyomavirus (JCPyV) and BK polyomavirus (BKPyV) is uncommon in kidney transplant recipients, and the prognosis is unclear. This study aimed to investigate the effect of concurrent JCPyV-DNAemia on graft outcomes in BKPyV-infected kidney transplant recipients with polyomavirus-associated nephropathy (PyVAN). METHODS: A total of 140 kidney transplant recipients with BKPyV replication and PyVAN, 122 without concurrent JCPyV-DNAemia and 18 with JCPyV-DNAemia were included in the analysis. Least absolute shrinkage and selection operator regression analysis and multivariate Cox regression analysis were used to identify prognostic factors for graft survival. A nomogram for predicting graft survival was created and evaluated. RESULTS: The median tubulitis score in the JCPyV-DNAemia-positive group was higher than in JCPyV-DNAemia-negative group ( P  = 0.048). At last follow-up, the graft loss rate in the JCPyV-DNAemia-positive group was higher than in the JCPyV-DNAemia-negative group (50% versus 25.4%; P  = 0.031). Kaplan-Meier analysis showed that the graft survival rate in the JCPyV-DNAemia-positive group was lower than in the JCPyV-DNAemia-negative group ( P  = 0.003). Least absolute shrinkage and selection operator regression and multivariate Cox regression analysis demonstrated that concurrent JCPyV-DNAemia was an independent risk factor for graft survival (hazard ratio = 4.808; 95% confidence interval: 2.096-11.03; P  < 0.001). The nomogram displayed favorable discrimination (C-index = 0.839), concordance, and clinical applicability in predicting graft survival. CONCLUSIONS: Concurrent JCPyV-DNAemia is associated with a worse graft outcome in BKPyV-infected kidney transplant recipients with PyVAN.


Subject(s)
DNA, Viral , Graft Survival , Kidney Transplantation , Polyomavirus Infections , Humans , Kidney Transplantation/adverse effects , Kidney Transplantation/mortality , Female , Male , Middle Aged , Polyomavirus Infections/virology , Polyomavirus Infections/diagnosis , Adult , DNA, Viral/blood , Retrospective Studies , BK Virus/pathogenicity , Risk Factors , Kidney Diseases/surgery , Kidney Diseases/virology , Kidney Diseases/mortality , Kidney Diseases/diagnosis , Tumor Virus Infections/virology , Tumor Virus Infections/diagnosis , Tumor Virus Infections/mortality , Treatment Outcome , Coinfection , Nomograms , Graft Rejection/virology , Aged
8.
Ren Fail ; 46(1): 2314630, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38345067

ABSTRACT

BACKGROUND: No study has validated, compared and adapted scoring systems for prognosis prediction based on donor kidney core biopsy (CB), with less glomeruli than wedge biopsy. METHODS: A total of 185 donor kidney CB specimens were reviewed using seven scoring systems. The association between the total score, item scores, score-based grading, and allograft prognosis was investigated. In specimens with less than ten glomeruli (88/185, 47.6%), scoring systems were modified by adjusting weights of the item scores. RESULTS: The Maryland aggregate pathology index (MAPI) score-based grading and periglomerular fibrosis (PGF) associated with delayed graft function (DGF) (Grade: OR = 1.59, p < 0.001; PGF: OR = 1.06, p = 0.006). Total score, score-based grading and chronic lesion score in scoring systems associated with one-year and 3-year eGFR after transplantation. Total-score-based models had similar predictive capacities for eGFR in all scoring systems, except MAPI and Ugarte. Score of glomerulosclerosis (GS), interstitial fibrosis (IF), tubular atrophy (TA), and arteriolar hyalinosis (AH) had good eGFR predictive capacities. In specimens with less than ten glomeruli, modified scoring systems had better eGFR predictive capacities than original scoring systems. CONCLUSIONS: Scoring systems could predict allograft prognosis in paraffin-embedded CB with ten more glomeruli. A simple and pragmatic scoring system should include GS, IF, TA and AH, with weights assigned based on predictive capacity for prognosis. Replacing GS scores with tubulointerstitial scores could significantly improve the predictive capacity of eGFR. The conclusion should be further validated in frozen section.


Subject(s)
Kidney Diseases , Kidney Transplantation , Humans , Kidney/pathology , Prognosis , Paraffin Embedding , Kidney Diseases/pathology , Biopsy , Fibrosis
10.
BMC Microbiol ; 24(1): 37, 2024 Jan 27.
Article in English | MEDLINE | ID: mdl-38279108

ABSTRACT

BACKGROUND: Vibrio vulnificus exists as one of the most serious foodborne pathogens for humans, and rapid and sensitive detection methods are needed to control its infections. As an emerging method, The Loop-Mediated Isothermal Amplification (LAMP) assay has been applied to the early detection of various foodborne pathogens due to its high efficiency, but sample preprocessing still prolongs the complete detection. To optimize the detection process, our study established a novel sample preprocessing method that was more efficient compared to common methods. RESULT: Using V. vulnificus as the detecting pathogen, the water-lysis-based detecting LAMP method shortened the preprocessing time to ≤ 1 min with 100% LAMP specificity; the detection limits of the LAMP assay were decreased to 1.20 × 102 CFU/mL and 1.47 × 103 CFU/g in pure culture and in oyster, respectively. Furthermore, the 100% LAMP specificity and high sensitivity of the water-lysis method were also obtained on detecting V. parahaemolyticus, V. alginolyticus, and P. mirabilis, revealing its excellent LAMP adaption with improvement in sensitivity and efficiency. CONCLUSION: Our study provided a novel LAMP preprocessing method that was more efficient compared to common methods and possessed the practical potential for LAMP application in the future.


Subject(s)
Molecular Diagnostic Techniques , Vibrio vulnificus , Humans , Vibrio vulnificus/genetics , Nucleic Acid Amplification Techniques/methods , Water , Specimen Handling , Sensitivity and Specificity
11.
J Formos Med Assoc ; 123(1): 7-15, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37690868

ABSTRACT

Melanoma is rare in Taiwan. Asian melanoma is distinct from Western melanoma because acral and mucosal melanoma accounts for the majority of melanoma cases, leading to distinct tumor behaviors and genetic profiling. With consideration of the clinical guidelines in Western countries, Taiwanese experts developed a local clinical practice consensus guideline. This consensus includes diagnosis, staging, and surgical and systemic treatment, based only on clinical evidence, local epidemiology, and available resources evaluated by experts in Taiwan. This consensus emphasizes the importance of surgical management, particularly for sentinel lymph node biopsies. In addition, molecular testing for BRAF is mandatory for patients before systemic treatment. Furthermore, immunotherapy and targeted therapy are prioritized for systemic treatment. This consensus aimed to assist clinicians in Taiwan in diagnosing and treating patients according to available evidence.


Subject(s)
Melanoma , Skin Neoplasms , Humans , Melanoma/diagnosis , Melanoma/therapy , Skin Neoplasms/diagnosis , Skin Neoplasms/therapy , Skin Neoplasms/genetics , Taiwan , Immunotherapy , Consensus
12.
Psychiatry Res ; 330: 115556, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37951032

ABSTRACT

We investigated whether changes through doubling the duration of each tDCS session would increase efficacy of tDCS for depression. tDCS was applied for 10 sessions, followed by two additional weekly sessions. 63 patients with MDD underwent randomization, with 22 being assigned to 60-min/d group, 25 to 30 min/d group, and 16 to sham group. HAMD-17 reductive ratios at week 2 and 4 were of no significant differences among treatment groups. 60 min group had a greater decrease in anxiety compared to 30 min group and sham group based on HAMA at 4 weeks but only in the completer analysis, not in ITT analysis.


Subject(s)
Depressive Disorder, Major , Transcranial Direct Current Stimulation , Humans , Anxiety , Depression , Depressive Disorder, Major/therapy , Suicidal Ideation , Transcranial Direct Current Stimulation/methods , Treatment Outcome , Time Factors
13.
Eur J Med Chem ; 261: 115855, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-37847955

ABSTRACT

In view of the fact that the G-protein-coupled receptors (GPCRs) sit at the top of the signaling pathways triggering a diverse range of signaling cascades towards a cellular event, GPCRs are regarded as central drug targets. mGlu5, a type of classical GPCRs, is highly expressed in the central nervous system (CNS) and responds to the neurotransmitter glutamate. Researches show that mGlu5 is a potential drug target for the treatment of depression. Up to now, multiple mGlu5 negative allosteric modulators (NAMs) have entered clinical trials, but no small molecule mGlu5 NAM has yet to reach market. Herein, we report the structural optimization and structure-activity relationship studies of a series of novel mGlu5 NAMs. Among them, the novel compound 10b is a high-affinity mGluR5 antagonist, with an IC50 value of 11.5 nM. Besides, we evaluated the anti-depressant effect of compound 10b using the chronic unpredictable mild stress (CUMS)-induced depression model. The data showed that the mice in CUMS group were featured by decreased level of serum 5-HT and increased level of serum CORT, and the expression of synaptic proteins were reduced, including GluA1, GluA2, p-PKA, BDNF and TrkB. However, those factors for identifying sensitivity to depression-like behaviors could be improved by compound 10b treatment. The preliminary toxicology evaluations indicated that compound 10b had a good safety profile in vivo. Collectively, the compound 10b represents a promising lead compound for the treatment of depressive disorder.


Subject(s)
Depressive Disorder , Pyrimidines , Mice , Animals , Pyrimidines/pharmacology , Pyrimidines/chemistry , Allosteric Regulation , Structure-Activity Relationship , Central Nervous System , Receptors, G-Protein-Coupled
14.
J Psychiatr Res ; 165: 41-47, 2023 09.
Article in English | MEDLINE | ID: mdl-37459777

ABSTRACT

OBJECTIVE: To explore the factors influencing anhedonia at baseline and use them as confounding factors. To further investigate the correlation between overt aggression and anhedonia during the acute phase of major depressive disorder. METHODS: In this eight-week prospective study, 384 major depressive disorder patients were recruited from the outpatient section of Shanghai Mental Health Center from May 1, 2017, to October 30, 2018. Standard treatments were performed with escitalopram or venlafaxine for participants. Depressive symptoms, overt aggression, and anhedonia were assessed using the 17-item Hamilton Rating Scale for Depression, Modified Overt Aggression Scale, and Snaith-Hamilton Pleasure Scale at baseline, and in the 4th and 8th weeks. RESULTS: Obsessive-compulsive symptoms and the duration of untreated psychosis were positively associated with aggression (P < 0.05). Patients with aggressive behaviour had worse cognitive impairment and severe anhedonia of pleasurable sensory experiences (P < 0.05). For anhedonia, being female (tau_b = -0.23, P = 0.012) was a protective factor, while number of recurrent, melancholic features, current obsessions, previous combination drug therapies, depressive symptoms, and aggressive behaviour were risk factors (P < 0.05). Social anhedonia related to interests/pastimes, and pleasurable sensory experiences were more severe in major depressive disorder patients with aggressive behaviour in the acute phase (P < 0.05). CONCLUSIONS: Anhedonia persisted in major depressive disorder patients with aggressive behaviour after standardized treatment during the acute phase. Being female protected the pleasures from social interaction and sensory experience. However, the number of depressive episodes, melancholic features, current obsessive symptoms, previous combination drug therapies, depressive symptoms, and aggressive behaviour was positively associated with anhedonia.


Subject(s)
Depressive Disorder, Major , Humans , Female , Male , Depressive Disorder, Major/complications , Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/diagnosis , Anhedonia , Prospective Studies , China , Aggression
15.
Adv Sci (Weinh) ; 10(27): e2302640, 2023 09.
Article in English | MEDLINE | ID: mdl-37485650

ABSTRACT

Hepatocellular carcinoma (HCC) is one of the most lethal cancers worldwide. Patient-derived organoid (PDO) has great potential in precision oncology, but low success rate, time-consuming culture, and lack of tumor microenvironment (TME) limit its application. Mesenchymal stromal cells (MSC) accumulate in primary site to support tumor growth and recruit immune cells to form TME. Here, MSC and peripheral blood mononuclear cells (PBMC) coculture is used to construct HCC organoid-on-a-chip mimicking original TME and provide a high-throughput drug-screening platform to predict outcomes of anti-HCC immunotherapies. HCC-PDOs and PBMC are co-cultured with MSC and Cancer-associated fibroblasts (CAF). MSC increases success rate of biopsy-derived PDO culture, accelerates PDO growth, and promotes monocyte survival and differentiation into tumor-associated macrophages. A multi-layer microfluidic chip is designed to achieve high-throughput co-culture for drug screening. Compared to conventional PDOs, MSC-PDO-PBMC and CAF-PDO-PBMC models show comparable responses to chemotherapeutic or targeted anti-tumor drugs but more precise prediction potential in assessing patients' responses to anti-PD-L1 drugs. Moreover, this microfluidic platform shortens PDO growth time and improves dimensional uniformity of organoids. In conclusion, the study successfully constructs microengineered organoid-on-a-chip to mimic TME for high-throughput drug screening, providing novel platform to predict immunotherapy response of HCC patients.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Mesenchymal Stem Cells , Humans , Carcinoma, Hepatocellular/therapy , Leukocytes, Mononuclear , Liver Neoplasms/therapy , Precision Medicine , Organoids , Immunotherapy , Lab-On-A-Chip Devices , Tumor Microenvironment
16.
Pediatr Surg Int ; 39(1): 230, 2023 Jul 10.
Article in English | MEDLINE | ID: mdl-37428242

ABSTRACT

AIM: This study aims to explore the application of RENAL nephrometry scoring system in bilateral Wilms tumor (BWT). METHODS: A retrospective review of patients with BWT from January 2010 to June 2022 was performed. Each kidney unit of the BWT was evaluated independently and scored according to RENAL nephrometry scoring system by 2 blinded reviewers, and reviewers were blinded to what surgery the patients ultimately had. Discrepancies were evaluated by a third reviewer to reach a consensus. Tumor anatomical characteristics were summarized and compared. RESULTS: 29 patients with 53 kidney units were included in the study. 53 kidney units included 12 (22.6%) low-complexity, 9 (17.0%) intermediate-complexity, and 32 (60.4%) high-complexity. 2 kidney units (3.8%) had tumor thrombus, and 14 (26.4%) had multiple lesions. A total of 42 kidney units (79.2%) underwent initial nephron-sparing surgery (NSS) and 11 (20.8%) underwent radical nephrectomy. Less complexity tumors were observed in the NSS group. Of the 42 kidney units undergoing initial NSS, 26 were performed in vivo and 16 ex vivo via autotransplantation. The latter group featured a higher complexity. During follow-up, 22 patients survived and 7 died, no statistically significant tumor complexity was observed between the two groups. CONCLUSIONS: The anatomical characteristics of BWT are complex. Despite this study did not indicate that the complexity correlates with prognosis, low-complexity tumors were candidates for NSS, and kidney autotransplantation provided a feasible procedure for high-complexity tumors. A refined system is required due to multiple lesions and tumor thrombus.


Subject(s)
Kidney Neoplasms , Wilms Tumor , Humans , Kidney Neoplasms/surgery , Kidney Neoplasms/pathology , Wilms Tumor/surgery , Wilms Tumor/pathology , Kidney/diagnostic imaging , Kidney/surgery , Nephrectomy/methods , Prognosis , Retrospective Studies , Nephrons/pathology , Nephrons/surgery
17.
Small ; 19(39): e2302499, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37254463

ABSTRACT

Mechanical properties of graphene, e.g., strength, modulus, and fracture toughness are extremely sensitive to flaws. Here the fracture properties of stacked bilayer graphene sheets (SBLG) are reported, obtained via stacking two individually grown graphene sheets. The SBLG is presented here as a building block for flaw-resilient nanomaterials. The fracture properties of freestanding SBLG sheets, suspended on transmission electron microscope (TEM) grids, are characterized by stretching the TEM grid inside an scanning electron microscope (SEM) chamber and monitoring the local displacements in real-time. The fracture toughness is measured and expressed as a function of the critical displacement required to propagate existing cracks in the experiment via computational models. This approach decouples force and displacements measurements, and utilizes the known elastic modulus along with the known displacement boundary conditions at the onset of crack growth to estimate the far field force and stress. This strategy represents a breakthrough in nanoscale fracture mechanics for statistical analysis and high throughput experimens on multiple samples at a time. Results demonstrate that the SBLG is markedly tougher than as-grown single or multilayer graphene, with a mode I fracture toughness of ≈28.06 ± 7.5 MPa m $\sqrt m $ . The mechanisms leading to a higher toughness of SBLG are also analyzed and discussed.

18.
J Colloid Interface Sci ; 644: 533-545, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37012113

ABSTRACT

Metal-organic polymers (MOPs) can enhance the photoelectrochemical (PEC) water oxidation performance of BiVO4 photoanodes, but their PEC mechanisms have yet to be comprehended. In this work, we constructed an active and stable composite photoelectrode by overlaying a uniform MOP on the BiVO4 surface using Fe2+ as the metal ions and 2,5-dihydroxyterephthalic acid (DHTA) as ligand. Such modification on the BiVO4 surface yielded a core-shell structure that could effectively enhance the PEC water oxidation activity of the BiVO4 photoanode. Our intensity-modulated photocurrent spectroscopy analysis revealed that the MOP overlayer could concurrently reduce the surface charge recombination rate constant (ksr) and enhance the charge transfer rate constant (ktr), thus accelerating water oxidation activity. These phenomena can be ascribed to the passivation of the surface that inhibits the recombination of the charge carrier and the MOP catalytic layer that improves the hole transfer. Our rate law analysis also demonstrated that the MOP coverage shifted the reaction order of the BiVO4 photoanode from the third-order to the first-order, resulting in a more favorable rate-determining step where only one hole accumulation is required to overcome water oxidation. This work provides new insights into the reaction mechanism of MOP-modified semiconductor photoanodes.

19.
Transl Pediatr ; 12(2): 280-286, 2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36891364

ABSTRACT

Background: Intussusception is a frequent abdominal emergency in the pediatric population when the proximal bowel invaginates into the distal bowel. However, catheter-induced intussusception has not previously been described in pediatric renal transplant recipients, and the risk factors need to be investigated. Case Description: We report 2 cases of post-transplant intussusception which were caused by abdominal catheters. Case 1 experienced ileocolonic intussusception 3 months after renal transplantation and presented with intermittent abdominal pain; the intussusception was successfully managed using air enema. However, this child experienced a total of 3 episodes of intussusception within 4 days, which discontinued only after removal of the peritoneal dialysis catheter. No further intussusception recurrence was observed and the patient's intermittent pain disappeared during the follow-up. Case 2 developed ileocolonic intussusception 2 days after renal transplantation and presented currant jelly stools. The intussusception was completely irreducible until the intraperitoneal drainage catheter was eliminated; the patient discharged normal feces during the following days. A search in the databases of PubMed, Web of Science, and Embase yielded 8 similar cases. Our 2 cases had a younger age at disease onset than those retrieved in the search, and abdominal catheter was revealed as a lead point. Possible leading points of the 8 previously reported cases included post-transplant lymphoproliferative disorder (PTLD), acute appendicitis, tuberculosis, lymphocele, and firm adhesions. We noted that our cases were managed successfully with nonoperative treatment, whereas the 8 reported cases underwent surgical intervention. All of the 10 cases of intussusception occurred after renal transplantation and showed that intussusception had been induced by a lead point. Conclusions: Our 2 cases implied that abdominal catheter could be a lead point to induce intussusception, especially in pediatric recipients with abdominal disorder. This experience may be applicable to other surgeries involving indwelling abdominal catheters in children. Health practitioners should consider this pathologic lead point and avoid serious consequences when intussusception occurs.

20.
Adv Mater ; 35(26): e2211432, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36941204

ABSTRACT

Bacterial infections, such as bacterial keratitis (BK) and subcutaneous abscess, pose significant challenges to global healthcare. Innovative and new antibacterial agents and antibacterial strategies are in demand to control infections in this era of high drug resistance. Nanotechnology is gradually emerging as an economically feasible and effective anti-infection treatment. High-entropy MXenes (HE MXenes) are used to confer desirable properties with exposed active sites to high-entropy atomic layers, whose potential application in the field of biomedicine remains to be explored. Herein, monolayer HE MXenes are fabricated by implementing transition metals with high entropy and low Gibbs free energy to fill the gap in the biocatalytic performance of non-high-entropy MXenes. HE MXenes are endowed with extremely strong oxidase mimic activity (Km = 0.227 mm) and photothermal conversion efficiency (65.8%) in the second near-infrared (NIR-II) biowindow as entropy increases. Subsequently, HE MXenes realize NIR-II-enhanced intrinsic oxidase mimic activity for killing methicillin-resistant Staphylococcus aureus and rapidly removing the biofilm. Furthermore, HE MXenes can effectively treat BK and subcutaneous abscess infection induced by methicillin-resistant Staphylococcus aureus as nanotherapeutic agents with minuscule side effects. Overall, monolayer HE MXenes demonstrate promising clinical application potential in the treatment of drug-resistant bacterial infections and promote the healing of infected tissues.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Humans , Oxidoreductases , Abscess/drug therapy , Entropy , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/chemistry
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