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1.
Environ Sci Technol ; 2024 May 10.
Article En | MEDLINE | ID: mdl-38728016

The urgent environmental concern of methane abatement, attributed to its high global warming potential, necessitates the development of methane oxidation catalysts (MOC) with enhanced low-temperature activity and durability. Herein, an iridium-doped PdOx nanoparticle supported on silicalite-1 zeolite (PdIr/S-1) catalyst was synthesized and applied for methane catalytic combustion. Comprehensive characterizations confirmed the atomically dispersed nature of iridium on the surface of PdOx nanoparticles, creating an Ir4f-O-Pdcus microstructure. The atomically doped Ir transferred more electrons to adjacent oxygen atoms, modifying the electronic structure of PdOx and thus enhancing the redox ability of the PdIr/S-1 catalysts. This electronic modulation facilitated methane adsorption on the Pd site of Ir4f-O-Pdcus, reducing the energy barrier for C-H bond cleavage and thereby increasing the reaction rate for methane oxidation. Consequently, the optimized PdIr0.1/S-1 showed outstanding low-temperature activity for methane combustion (T50 = 276 °C) after aging and maintained long-term stability over 100 h under simulated exhaust conditions. Remarkably, the novel PdIr0.1/S-1 catalyst demonstrated significantly enhanced activity even after undergoing harsh hydrothermal aging at 750 °C for 16 h, significantly outperforming the conventional Pd/Al2O3 catalyst. This work provides valuable insights for designing efficient and durable MOC catalysts, addressing the critical issue of methane abatement.

2.
Angew Chem Int Ed Engl ; : e202402133, 2024 May 06.
Article En | MEDLINE | ID: mdl-38708621

We describe small heterojunction polymer dots (Pdots) with deep-red light catalyzed H2 generation for diabetic skin wound healing. The Pdots with donor/acceptor heterojunctions showed remarkably enhanced photocatalytic activity as compared to the donor or acceptor nanoparticles alone. We encapsulate the Pdots and ascorbic acid into liposomes to form Lipo-Pdots nanoreactors, which selectively scavenge •OH radicals in live cells and tissues under 650 nm light illumination. The antioxidant capacity of the heterojunction Pdots is ~10 times higher than that of the single-component Pdots described previously. Under a total light dose of 360 J/cm2, the Lipo-Pdots nanoreactors effectively scavenged •OH radicals and suppressed the expression of pro-inflammatory cytokines in skin tissues, thereby accelerating the healing of skin wounds in diabetic mice. This study provides a feasible solution for safe and effective treatment of diabetic foot ulcers.

3.
Front Surg ; 11: 1370702, 2024.
Article En | MEDLINE | ID: mdl-38742149

Background and objective: Surgery is the primary therapy that crucially affects the survival of patients with kidney cancer (KC). However, pertinent surgical decision criteria for individuals with stage T2-3 KC are lacking. This study aimed to display the practical choices and evolving trends of surgical procedures and elucidate their implied value. Methods: Through the Surveillance, Epidemiology, and End Results (SEER) dataset, the levels and evolving trends of different surgical methods were examined to determine cancer-specific risk of death (CSRD). Additionally, stratification analysis and survival rate analysis were performed to explore the effectiveness of partial nephrectomy (PN). Results: In this study, 9.27% of patients opted for PN. Interestingly, an upward trend was observed in its decision, with an average annual percentage change (AAPC) of 7.0 (95% CI: 4.8-9.3, P < 0.05). Patients who underwent PN and were in a relatively less severe condition exhibited more favorable CSRD levels (0.17-0.36 vs. 0.50-0.67) and an improvement trend compared with those who underwent radical nephrectomy (RN) (AAPC: -1.9 vs. -0.8). Further analysis showed that the levels of CSRD and survival rates for patients opting for different surgical methods followed a similar pattern. Conclusions: This study showed that RN was still the most common surgical method. Patients with stage T2-3 KC had an increasing preference for PN and exhibited more favorable cancer-related survival outcomes, which underscores the need for further investigation and validation.

4.
J Nanobiotechnology ; 22(1): 257, 2024 May 16.
Article En | MEDLINE | ID: mdl-38755645

Imperceptible examination and unideal treatment effect are still intractable difficulties for the clinical treatment of pancreatic ductal adenocarcinoma (PDAC). At present, despite 5-fluorouracil (5-FU), as a clinical first-line FOLFIRINOX chemo-drug, has achieved significant therapeutic effects. Nevertheless, these unavoidable factors such as low solubility, lack of biological specificity and easy to induce immunosuppressive surroundings formation, severely limit their treatment in PDAC. As an important source of energy for many tumor cells, tryptophan (Trp), is easily degraded to kynurenine (Kyn) by indolamine 2,3- dioxygenase 1 (IDO1), which activates the axis of Kyn-AHR to form special suppressive immune microenvironment that promotes tumor growth and metastasis. However, our research findings that 5-FU can induce effectively immunogenic cell death (ICD) to further treat tumor by activating immune systems, while the secretion of interferon-γ (IFN-γ) re-induce the Kyn-AHR axis activation, leading to poor treatment efficiency. Therefore, a metal matrix protease-2 (MMP-2) and endogenous GSH dual-responsive liposomal-based nanovesicle, co-loading with 5-FU (anti-cancer drug) and NLG919 (IDO1 inhibitor), was constructed (named as ENP919@5-FU). The multifunctional ENP919@5-FU can effectively reshape the tumor immunosuppression microenvironment to enhance the effect of chemoimmunotherapy, thereby effectively inhibiting cancer growth. Mechanistically, PDAC with high expression of MMP-2 will propel the as-prepared nanovesicle to dwell in tumor region via shedding PEG on the nanovesicle surface, effectively enhancing tumor uptake. Subsequently, the S-S bond containing nanovesicle was cut via high endogenous GSH, leading to the continued release of 5-FU and NLG919, thereby enabling circulating chemoimmunotherapy to effectively cause tumor ablation. Moreover, the combination of ENP919@5-FU and PD-L1 antibody (αPD-L1) showed a synergistic anti-tumor effect on the PDAC model with abdominal cavity metastasis. Collectively, ENP919@5-FU nanovesicle, as a PDAC treatment strategy, showed excellent antitumor efficacy by remodeling tumor microenvironment to circulate tumor chemoimmunotherapy amplification, which has promising potential in a precision medicine approach.


Carcinoma, Pancreatic Ductal , Fluorouracil , Immunotherapy , Tumor Microenvironment , Tumor Microenvironment/drug effects , Animals , Fluorouracil/pharmacology , Fluorouracil/therapeutic use , Mice , Humans , Immunotherapy/methods , Cell Line, Tumor , Carcinoma, Pancreatic Ductal/drug therapy , Pancreatic Neoplasms/drug therapy , Matrix Metalloproteinase 2/metabolism , Liposomes/chemistry , Kynurenine/metabolism , Interferon-gamma/metabolism , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/chemistry , Oxaliplatin/pharmacology , Oxaliplatin/therapeutic use
5.
Brain Sci ; 14(5)2024 May 15.
Article En | MEDLINE | ID: mdl-38790476

In this study, we investigated the feasibility of using electroencephalogram (EEG) signals to differentiate between four distinct subject-driven cognitive states: resting state, narrative memory, music, and subtraction tasks. EEG data were collected from seven healthy male participants while performing these cognitive tasks, and the raw EEG signals were transformed into time-frequency maps using continuous wavelet transform. Based on these time-frequency maps, we developed a convolutional neural network model (TF-CNN-CFA) with a channel and frequency attention mechanism to automatically distinguish between these cognitive states. The experimental results demonstrated that the model achieved an average classification accuracy of 76.14% in identifying these four cognitive states, significantly outperforming traditional EEG signal processing methods and other classical image classification algorithms. Furthermore, we investigated the impact of varying lengths of EEG signals on classification performance and found that TF-CNN-CFA demonstrates consistent performance across different window lengths, indicating its strong generalization capability. This study validates the ability of EEG to differentiate higher cognitive states, which could potentially offer a novel BCI paradigm.

6.
Virus Genes ; 60(3): 320-324, 2024 Jun.
Article En | MEDLINE | ID: mdl-38722491

H6 avian influenza virus is widely prevalent in wild birds and poultry and has caused human infection in 2013 in Taiwan, China. During our active influenza surveillance program in wild waterfowl at Poyang Lake, Jiangxi Province, an H6N2 AIV was isolated and named A/bean goose/JiangXi/452-4/2013(H6N2). The isolate was characterized as a typical low pathogenic avian influenza virus (LPAIV) due to the presence of the amino acid sequence PQIETR↓GLFGAI at the cleavage site of the hemagglutinin (HA) protein. The genetic evolution analysis revealed that the NA gene of the isolate originated from North America and exhibited the highest nucleotide identity (99.29%) with a virus recovered from wild bird samples in North America, specifically A/bufflehead/California/4935/2012(H11N2). Additionally, while the HA and PB1 genes belonged to the Eurasian lineage, they displayed frequent genetic interactions with the North American lineage. The remaining genes showed close genetic relationships with Eurasian viruses. The H6N2 isolate possessed a complex genome, indicating it is a multi-gene recombinant virus with genetic material from both Eurasian and North American lineages.


Animals, Wild , Influenza A virus , Influenza in Birds , Phylogeny , Reassortant Viruses , Animals , China , Reassortant Viruses/genetics , Reassortant Viruses/isolation & purification , Reassortant Viruses/classification , Influenza in Birds/virology , Animals, Wild/virology , Influenza A virus/genetics , Influenza A virus/isolation & purification , Influenza A virus/classification , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Birds/virology , Evolution, Molecular , Genome, Viral/genetics , Neuraminidase/genetics , Viral Proteins/genetics
7.
Biochem Pharmacol ; 225: 116310, 2024 May 22.
Article En | MEDLINE | ID: mdl-38788960

Targeting the DNA damage response (DDR) is a promising strategy in oncotherapy, as most tumor cells are sensitive to excess damage due to their repair defects. Ataxia telangiectasia mutated and RAD3-related protein (ATR) is a damage response signal transduction sensor, and its therapeutic potential in tumor cells needs to be precisely investigated. Herein, we identified a new axis that could be targeted by ATR inhibitors to decrease the DNA-dependent protein kinase catalytic subunit (DNAPKcs), downregulate the expression of the retinoblastoma (RB), and drive G1/S-phase transition. Four-way DNA Holliday junctions (FJs) assembled in this process could trigger S-phase arrest and induce lethal chromosome damage in RB-positive triple-negative breast cancer (TNBC) cells. Furthermore, these unrepaired junctions also exerted toxic effects to RB-deficient TNBC cells when the homologous recombination repair (HRR) was inhibited. This study proposes a precise strategy for treating TNBC by targeting the DDR and extends our understanding of ATR and HJ in tumor treatment.

8.
Molecules ; 29(10)2024 May 19.
Article En | MEDLINE | ID: mdl-38792257

Glioblastoma multiforme, a highly aggressive and lethal brain tumor, is a substantial clinical challenge and a focus of increasing concern globally. Hematological toxicity and drug resistance of first-line drugs underscore the necessity for new anti-glioma drug development. Here, 43 anthracenyl skeleton compounds as p53 activator XI-011 analogs were designed, synthesized, and evaluated for their cytotoxic effects. Five compounds (13d, 13e, 14a, 14b, and 14n) exhibited good anti-glioma activity against U87 cells, with IC50 values lower than 2 µM. Notably, 13e showed the best anti-glioma activity, with an IC50 value up to 0.53 µM, providing a promising lead compound for new anti-glioma drug development. Mechanistic analyses showed that 13e suppressed the MDM4 protein expression, upregulated the p53 protein level, and induced cell cycle arrest at G2/M phase and apoptosis based on Western blot and flow cytometry assays.


Antineoplastic Agents , Apoptosis , Glioblastoma , Tumor Suppressor Protein p53 , Humans , Glioblastoma/drug therapy , Glioblastoma/metabolism , Glioblastoma/pathology , Tumor Suppressor Protein p53/metabolism , Cell Line, Tumor , Apoptosis/drug effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Anthracenes/pharmacology , Cell Proliferation/drug effects , Brain Neoplasms/drug therapy , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Proto-Oncogene Proteins/metabolism , Cell Cycle Proteins/metabolism
9.
Front Oncol ; 14: 1349888, 2024.
Article En | MEDLINE | ID: mdl-38800400

Objective: The aim of this study is to examine the predictive factors for cancer-specific survival (CSS) in patients diagnosed with Small-Cell Carcinoma of the Prostate (SCCP) and to construct a prognostic model. Methods: Cases were selected using the Surveillance, Epidemiology, and End Results (SEER) database. The Kaplan-Meier method was utilized to calculate survival rates, while Lasso and Cox regression were employed to analyze prognostic factors. An independent prognostic factor-based nomogram was created to forecast CSS at 12 and 24 months. The model's predictive efficacy was assessed using the consistency index (C-index), calibration curve, and decision curve analysis (DCA) in separate tests. Results: Following the analysis of Cox and Lasso regression, age, race, Summary stage, and chemotherapy were determined to be significant risk factors (P < 0.05). In the group of participants who received training, the rate of 12-month CSS was 44.6%, the rate of 24-month CSS was 25.5%, and the median time for CSS was 10.5 months. The C-index for the training cohort was 0.7688 ± 0.024. As for the validation cohort, it was 0.661 ± 0.041. According to the nomogram, CSS was accurately predicted and demonstrated consistent and satisfactory predictive performance at both 12 months (87.3% compared to 71.2%) and 24 months (80.4% compared to 71.7%). As shown in the external validation calibration plot, the AUC for 12- and 24-month is 64.6% vs. 56.9% and 87.0% vs. 70.7%, respectively. Based on the calibration plot of the CSS nomogram at both the 12-month and 24-month marks, it can be observed that both the actual values and the nomogram predictions indicate a predominantly stable CSS. When compared to the AJCC staging system, DCA demonstrated a higher level of accuracy in predicting CSS through the use of a nomogram. Conclusion: Clinical prognostic factors can be utilized with nomograms to forecast CSS in Small-Cell Carcinoma of the Prostate (SCCP).

10.
Phytochem Anal ; 2024 May 20.
Article En | MEDLINE | ID: mdl-38768606

INTRODUCTION: Lipid molecules are present in tumours and play an important role in the anti-inflammatory response as well as in antiviral protection. Changes in the type and location of lipids in the intestine following exposure to environmental stressors play an important role in several disorders, including ulcerative colitis (UC), inflammatory bowel disease (IBD), and colorectal cancer. OBJECTIVES: The aim of this work is to provide a new theoretical basis for tumour initiation and development by accurately measuring the spatial distribution of lipids and metabolites in intestinal tissue. Spatial metabolomics allows the detection of samples with minimal sample volume by label-free imaging of complex samples in their original state. The distribution of lipid molecules in tumours has not been reported, although the distribution of lipid molecules in intestinal tissue has been reported in the literature. METHODS: The range of lipid profiles in colon cancer mouse tumour tissue was compiled using a spatial metabolomics: lipid extraction method. The changes in lipid distribution in two regions after oral administration of American Ginseng (Panax quinquefolius L.) vesicles were also compared. Tumour tissue samples were extracted with 80% methanol-20% formic acid in water. RESULTS: The resulting spatial metabolic profile allowed the identification of seven lipid classes in mouse tumours. The distribution of fibre tissue cells was 23.2% higher than tumour tissue cells, with the exception of the fatty acid (FA) species.

12.
Am J Transl Res ; 16(3): 955-963, 2024.
Article En | MEDLINE | ID: mdl-38586097

OBJECTIVE: To observe the multi-slice spiral CT angiography (MSCTA) imaging features of arteriovenous fistula dysfunction in patients undergoing maintenance hemodialysis and analyze the significance of the imaging examination. METHODS: Altogether 90 patients with end-stage renal disease treated by maintenance hemodialysis in General Hospital of China Resources & Wisco from June 2020 to February 2023 were divided into a normal function group (n=68) and a dysfunction group (n=22) according to the function of autogenous arteriovenous fistula. The clinical data of the two groups were recorded. The MSCTA was performed in each patient, and the manifestations of arteriovenous fistula dysfunction were analyzed. Additionally, the vascular access stenosis, vascular access lumen stenosis, arteriovenous diameter, blood flow, and hemodynamic indices were tested, and the value of MSCTA in predicting arteriovenous fistula function was analyzed by Logistic regression. RESULTS: The degree of vascular access stenosis and vascular access lumen stenosis in the normal group were less than those in the dysfunctional group (P<0.05). The arteriovenous diameter, blood flow, blood flow velocity at anastomotic vein end, dialysis adequacy (spKt/V), and von Willebrand factor (vWF) function in the normal group were larger than those in the dysfunction group, and the radial artery shear force was lower than in the dysfunction group, with statistical significance (P<0.05). Among the arteriovenous fistula dysfunction, there were 3 patients with anastomotic + outflow vein stenosis, 4 patients with outflow vein stenosis, 9 patients with inflow artery + anastomosis + outflow vein stenosis, and 6 patients with superior vena cava stenosis. Logistic regression analysis showed that slow blood flow velocity at the venous end of anastomosis and high shear force of radial artery were influencing factors of arteriovenous fistula dysfunction, and the area under ROC curve of blood flow velocity at the venous end of anastomosis plus shear force of radial artery was 0.93, with a sensitivity of 0.87 and a specificity of 0.85. CONCLUSION: MSCTA can be used to evaluate the dysfunction of autologous arteriovenous fistula in patients undergoing maintenance hemodialysis, and provide important reference information for the formulation of the next best clinical treatment plan.

13.
Neurosurg Rev ; 47(1): 152, 2024 Apr 12.
Article En | MEDLINE | ID: mdl-38605210

Background- Postoperative delirium is a common complication associated with the elderly, causing increased morbidity and prolonged hospital stay. However, its risk factors in chronic subdural hematoma patients have not been well studied. Methods- A total of 202 consecutive patients with chronic subdural hematoma at Peking University Third Hospital between January 2018 and January 2023 were enrolled. Various clinical indicators were analyzed to identify independent risk factors for postoperative delirium using univariate and multivariate regression analyses. Delirium risk prediction models were developed as a nomogram and a Markov chain. Results- Out of the 202 patients (age, 71 (IQR, 18); female-to-male ratio, 1:2.7) studied, 63 (31.2%) experienced postoperative delirium. Univariate analysis identified age (p < 0.001), gender (p = 0.014), restraint belt use (p < 0.001), electrolyte imbalance (p < 0.001), visual analog scale score (p < 0.001), hematoma thickness (p < 0.001), midline shift (p < 0.001), hematoma side (p = 0.013), hematoma location (p = 0.018), and urinal catheterization (p = 0.028) as significant factors. Multivariate regression analysis confirmed the significance of restraint belt use (B = 7.657, p < 0.001), electrolyte imbalance (B = -3.993, p = 0.001), visual analog scale score (B = 2.331, p = 0.016), and midline shift (B = 0.335, p = 0.007). Hematoma thickness and age had no significant impact. Conclusion- Increased midline shift and visual analog scale scores, alongside restraint belt use and electrolyte imbalance elevate delirium risk in chronic subdural hematoma surgery. Our prediction models may offer reference value in this context.


Emergence Delirium , Hematoma, Subdural, Chronic , Humans , Male , Female , Aged , Hematoma, Subdural, Chronic/complications , Emergence Delirium/complications , Retrospective Studies , Risk Factors , Risk Assessment , Electrolytes
14.
Front Cell Neurosci ; 18: 1335688, 2024.
Article En | MEDLINE | ID: mdl-38572072

Introduction: Hypoxic-ischemic encephalopathy (HIE) is one of severe neonatal brain injuries, resulting from inflammation and the immune response after perinatal hypoxia and ischemia. IgG N-glycosylation plays a crucial role in various inflammatory diseases through mediating the balance between anti-inflammatory and pro-inflammatory responses. This study aimed to explore the effect of IgG N-glycosylation on the development of HIE. Methods: This case-control study included 53 HIE patients and 57 control neonates. An ultrahigh-performance liquid chromatography (UPLC) method was used to determine the features of the plasma IgG N-glycans, by which 24 initial glycan peaks (GPs) were quantified. Multivariate logistic regression was used to examine the association between initial glycans and HIE, by which the significant parameters were used to develop a diagnostic model. Though receiver operating characteristic (ROC) curves, area under the curve (AUC) and 95% confidence interval (CI) were calculated to assess the performance of the diagnostic model. Results: There were significant differences in 11 initial glycans between the patient and control groups. The levels of fucosylated and galactosylated glycans were significantly lower in HIE patients than in control individuals, while sialylated glycans were higher in HIE patients (p < 0.05). A prediction model was developed using three initial IgG N-glycans and fetal distress, low birth weight, and globulin. The ROC analysis showed that this model was able to discriminate between HIE patients and healthy individuals [AUC = 0.798, 95% CI: (0.716-0.880)]. Discussion: IgG N-glycosylation may play a role in the pathogenesis of HIE. Plasma IgG N-glycans are potential noninvasive biomarkers for screening individuals at high risk of HIE.

15.
RSC Adv ; 14(15): 10526-10537, 2024 Mar 26.
Article En | MEDLINE | ID: mdl-38567335

Ca-phosphate/-silicate ceramic granules have been widely studied because their biodegradable fillers can enhance bone defect repair accompanied with bioactive ion release and material degradation; however, it is a challenge to endow bioceramic composites with time-dependent ion release and highly efficient osteogenesis in vivo. Herein, we prepared dual-core-type bioceramic granules with varying chemical compositions beneficial for controlling ion release and stimulating osteogenic capability. Core-shell-structured bioceramic granules (P8-Sr4@Zn3, P8-Sr4@TCP, and P8-Sr4@HAR) composed of 8% P- and 4% Sr-substituting wollastonite (P8, Sr4) dual core components and different shell components, such as 3% Zn-substituting wollastonite (Zn3), ß-tricalcium phosphate (ß-TCP), and hardystonite (HAR), were prepared by cutting extruded core-shell fibers through dual-core ternary nozzles, followed by high-temperature sintering post-treatment. The experimental results showed that nonstoichiometric wollastonite core components contributed to more biologically active ion release in Tris buffer in vitro, and the sparingly dissolvable shell component readily maintained the granule morphology in vivo; thus, such bioceramic implants can adjust new bone growth and material degradation over time. In particular, bioceramic granules encapsulated by the TCP shell exhibited the most appreciable osteogenic capacity and expected biodegradation, which was mostly favorable for bone repair in critical bone defects. It is reasonable to consider that this new multiphasic bioceramic granule design is versatile for developing next-generation implants for various bone damage repairs.

16.
ACS Omega ; 9(16): 17989-18000, 2024 Apr 23.
Article En | MEDLINE | ID: mdl-38680346

In this study, a single factor exploration method was adopted to optimize the cotton shell-based activated carbon adsorption reaction time, temperature, pH value, initial concentration of cadmium ion, and other conditions. The experimental results showed that under the conditions of Cd2+ solution pH = 8, initial concentration of 100 mg/L, adsorption reaction time of 180 min, adsorption temperature of 45 °C, cotton shell-based activated carbon dosage of about 0.1 g, the removal rate of Cd2+ was 94.03%, the adsorption capacity was 51.95 mg/g, and the error was only 0.05%. The adsorption kinetic analysis of this study conforms to the quasi-second-order kinetic model, the adsorption isotherm analysis conforms to the Langmuir adsorption isothermal model, and the Gibbs free energy of the adsorption process is negative; the above simulation analysis also proves the spontaneity and feasibility of the adsorption process.

17.
J Hazard Mater ; 471: 134328, 2024 Jun 05.
Article En | MEDLINE | ID: mdl-38643575

The microbial degradation of polyethylene (PE) and polypropylene (PP) resins in rivers and lakes has emerged as a crucial issue in the management of microplastics. This study revealed that as the flow rate decreased longitudinally, ammonia nitrogen (NH4+-N), heavy fraction of organic carbon (HFOC), and small-size microplastics (< 1 mm) gradually accumulated in the deep and downstream estuarine sediments. Based on their surface morphology and carbonyl index, these sediments were identified as the potential hot zone for PE/PP degradation. Within the identified hot zone, concentrations of PE/PP-degrading genes, enzymes, and bacteria were significantly elevated compared to other zones, exhibiting strong intercorrelations. Analysis of niche differences revealed that the accumulation of NH4+-N and HFOC in the hot zone facilitated the synergistic coexistence of key bacteria responsible for PE/PP degradation within biofilms. The findings of this study offer a novel insight and comprehensive understanding of the distribution characteristics and synergistic degradation potential of PE/PP in natural freshwater environments.


Bacteria , Biodegradation, Environmental , Geologic Sediments , Polyethylene , Polypropylenes , Water Pollutants, Chemical , Polypropylenes/chemistry , Polyethylene/chemistry , Polyethylene/metabolism , Water Pollutants, Chemical/metabolism , Water Pollutants, Chemical/chemistry , Geologic Sediments/microbiology , Geologic Sediments/chemistry , Bacteria/metabolism , Bacteria/genetics , Microplastics/toxicity , Microplastics/metabolism , Fresh Water/microbiology , Estuaries
18.
J Am Chem Soc ; 146(12): 8768-8779, 2024 Mar 27.
Article En | MEDLINE | ID: mdl-38483318

2'-Deoxynucleosides and analogues play a vital role in drug development, but their preparation remains a significant challenge. Previous studies have focused on ß-2'-deoxynucleosides with the natural ß-configuration. In fact, their isomeric α-2'-deoxynucleosides also exhibit diverse bioactivities and even better metabolic stability. Herein, we report that both α- and ß-2'-deoxynucleosides can be prepared with high yields and stereoselectivity using a remote directing diphenylphosphinoyl (DPP) group. It is particularly efficient to prepare α-2'-deoxynucleosides with an easily accessible 3,5-di-ODPP donor. Instead of acting as a H-bond acceptor on a 2-(diphenylphosphinoyl)acetyl (DPPA) group in our previous studies for syn-facial O-glycosylation, the phosphine oxide moiety here acts as a remote participating group to enable highly antifacial N-glycosylation. This proposed remote participation mechanism is supported by our first characterization of an important 1,5-briged P-heterobicyclic intermediate via variable-temperature NMR spectroscopy. Interestingly, antiproliferative assays led to a α-2'-deoxynucleoside with IC50 values in the low micromole range against central nervous system tumor cell lines SH-SY5Y and LN229, whereas its ß-anomer exhibited no inhibition at 100 µM. Furthermore, the DPP group significantly enhanced the antitumor activities by 10 times.


Neuroblastoma , Phosphines , Humans , Glycosylation
19.
Article En | MEDLINE | ID: mdl-38536635

Porcine epidemic diarrhea virus (PEDV) infection results in significant mortality among newborn piglets, leading to substantial economic setbacks in the pig industry. Short-chain fatty acids (SCFA), the metabolites of intestinal probiotics, play pivotal roles in modulating intestinal function, enhancing the intestinal barrier, and bolstering immune responses through diverse mechanisms. The protective potential of Lactobacillus delbrueckii, Lactobacillus johnsonii, and Lactococcus lactis was first noted when administered to PEDV-infected piglets. Histological evaluations, combined with immunofluorescence studies, indicated that piglets receiving L. lactis displayed less intestinal damage, with diminished epithelial cell necrosis and milder injury levels. Differences in immunofluorescence intensity revealed a significant disparity in antigen content between the L. lactis and PEDV groups, suggesting that L. lactis might suppress PEDV replication, the intestine. We then assessed short-chain fatty acid content through targeted metabolomics, finding that acetate levels markedly varied from other groups. This protective impact was confirmed by administering acetate to PEDV-infected piglets. Data suggested that piglets receiving acetate exhibited resistance to PEDV. Flow cytometry analyses were conducted to evaluate the expression of innate and adaptive immune cells in piglets. Sodium acetate appeared to bolster innate immune defenses against PEDV, marked by elevated NK cell and macrophage counts in mesenteric lymph nodes, along with increased NK cells in the spleen and macrophages in the bloodstream. Acetic acid was also found to enhance the populations of CD8+ IFN-γ T cells in the blood, spleen, and mesenteric lymph, CD4+ IFN-γ T cells in mesenteric lymph nodes and spleen, and CD4+ IL-4+T cells in the bloodstream. Transcriptome analyses were carried out on the jejunal mucosa from piglets with PEDV-induced intestinal damage and from healthy counterparts with intact barriers. Through bioinformatics analysis, we pinpointed 189 significantly upregulated genes and 333 downregulated ones, with the PI3K-AKT, ECM-receptor interaction, and pancreatic secretion pathways being notably enriched. This transcriptomic evidence was further corroborated by western blot and qPCR. Short-chain fatty acids (SCFA) were found to modulate G protein-coupled receptor 41 (GPR41) and 43 (GPR43) in porcine intestinal epithelial cells (IPEC-J2). Post-acetic acid exposure, there was a notable upsurge in the ZO-1 barrier protein expression in IPEC-J2 compared to the unexposed control group (WT), while GPR43 knockdown inversely affected ZO-1 expression. Acetic acid amplified the concentrations of phosphorylated PI3K and AKT pivotal components of the PI3K/AKT pathway. Concurrently, the co-administration of AKT agonist SC79 and PI3K inhibitor LY294002 revealed acetic acid's role in augmenting ZO-1 expression via the P13K/AKT signaling pathway. This study demonstrates that acetic acid produced by Lactobacillus strains regulates intestinal barrier and immune functions to alleviate PEDV infection. These findings provide valuable insights for mitigating the impact of PEDV in the pig industry.

20.
Phys Med Biol ; 69(8)2024 Apr 03.
Article En | MEDLINE | ID: mdl-38484392

Objective.Monolithic crystal detectors are increasingly being applied in positron emission tomography (PET) devices owing to their excellent depth-of-interaction (DOI) resolution capabilities and high detection efficiency. In this study, we constructed and evaluated a dual-ended readout monolithic crystal detector based on a multiplexing method.Approach.We employed two 12 × 12 silicon photomultiplier (SiPM) arrays for readout, and the signals from the 12 × 12 array were merged into 12 X and 12 Y channels using channel multiplexing. In 2D reconstruction, three methods based on the centre of gravity (COG) were compared, and the concept of thresholds was introduced. Furthermore, a light convolutional neural network (CNN) was employed for testing. To enhance depth localization resolution, we proposed a method by utilizing the mutual information from both ends of the SiPMs. The source width and collimation effect were simulated using GEANT4, and the intrinsic spatial resolution was separated from the measured values.Main results.At an operational voltage of 29 V for the SiPM, an energy resolution of approximately 12.5 % was achieved. By subtracting a 0.8 % threshold from the total energy in every channel, a 2D spatial resolution of approximately 0.90 mm full width at half maximum (FWHM) can be obtained. Furthermore, a higher level of resolution, approximately 0.80 mm FWHM, was achieved using a CNN, with some alleviation of edge effects. With the proposed DOI method, a significant 1.36 mm FWHM average DOI resolution can be achieved. Additionally, it was found that polishing and black coating on the crystal surface yielded smaller edge effects compared to a rough surface with a black coating.Significance.The introduction of a threshold in COG method and a dual-ended readout scheme can lead to excellent spatial resolution for monolithic crystal detectors, which can help to develop PET systems with both high sensitivity and high spatial resolution.


Neural Networks, Computer , Positron-Emission Tomography , Positron-Emission Tomography/methods , Photons , Gravitation
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