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1.
World J Gastrointest Oncol ; 16(8): 3600-3623, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39171160

RESUMEN

BACKGROUND: Colorectal polyps, which are characterized by a high recurrence rate, represent preneoplastic conditions of the intestine. Due to unclear mechanisms of pathogenesis, first-line therapies for non-hereditary recurrent colorectal polyps are limited to endoscopic resection. Although recent studies suggest a mechanistic link between intestinal dysbiosis and polyps, the exact compositions and roles of bacteria in the mucosa around the lesions, rather than feces, remain unsettled. AIM: To clarify the composition and diversity of bacteria in the mucosa surrounding or 10 cm distal to recurrent intestinal polyps. METHODS: Mucosal samples were collected from four patients consistently with adenomatous polyps (Ade), seven consistently with non-Ade (Pol), ten with current Pol but previous Ade, and six healthy individuals, and bacterial patterns were evaluated by 16S rDNA sequencing. Linear discriminant analysis and Student's t-tests were used to identify the genus-level bacteria differences between groups with different colorectal polyp phenotypes. Pearson's correlation coefficients were used to evaluate the correlation between intestinal bacteria at the genus level and clinical indicators. RESULTS: The results confirmed a decreased level of probiotics and an enrichment of pathogenic bacteria in patients with all types of polyps compared to healthy individuals. These changes were not restricted to the mucosa within 0.5 cm adjacent to the polyps, but also existed in histologically normal tissue 10 cm distal from the lesions. Significant differences in bacterial diversity were observed in the mucosa from individuals with normal conditions, Pol, and Ade. Increased abundance of Gram-negative bacteria, including Klebsiella, Plesiomonas, and Cronobacter, was observed in Pol group and Ade group, suggesting that resistance to antibiotics may be one risk factor for bacterium-related harmful environment. Meanwhile, age and gender were linked to bacteria changes, indicating the potential involvement of sex hormones. CONCLUSION: These preliminary results support intestinal dysbiosis as an important risk factor for recurrent polyps, especially adenoma. Targeting specific pathogenic bacteria may attenuate the recurrence of polyps.

2.
Sci Rep ; 14(1): 18935, 2024 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-39147923

RESUMEN

Acute pancreatitis, a common exocrine inflammatory disease affecting the pancreas, is characterized by intense abdominal pain and multiple organ dysfunction. However, the alterations in retinal blood vessels among individuals with acute pancreatitis remain poorly understood. This study employed optical coherence tomography angiography (OCTA) to examine the superficial and deep retinal blood vessels in patients with pancreatitis. Sixteen patients diagnosed with pancreatitis (32 eyes) and 16 healthy controls (32 eyes) were recruited from the First Affiliated Hospital of Nanchang University for participation in the study. Various ophthalmic parameters, such as visual acuity, intraocular pressure, and OCTA image for retina consisting of the superficial retinal layer (SRL) and the deep retinal layer (DRL), were recorded for each eye. The study observed the superficial and deep retinal microvascular ring (MIR), macrovascular ring (MAR), and total microvessels (TMI) were observed. Changes in retinal vascular density in the macula through annular partitioning (C1-C6), hemispheric quadrant partitioning (SR, SL, IL, and IR), and early diabetic retinopathy treatment studies (ETDRS) partitioning methods (R, S, L, and I). Correlation analysis was employed to investigate the relationship between retinal capillary density and clinical indicators. Our study revealed that in the superficial retinal layer, the vascular density of TMI, MIR, MAR, SR, IR, S, C2, C3 regions were significantly decreased in patients group compared with the normal group. For the deep retinal layer, the vascular density of MIR, SR, S, C1, C2 regions also reduced in patient group. The ROC analysis demonstrated that OCTA possesses significant diagnostic performance for pancreatitis. In conclusion, patients with pancreatitis may have retinal microvascular dysfunction, and OCTA can be a valuable tool for detecting alterations in ocular microcirculation in pancreatitis patients in clinical practice.


Asunto(s)
Pancreatitis , Vasos Retinianos , Tomografía de Coherencia Óptica , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios de Casos y Controles , Relevancia Clínica , Microvasos/diagnóstico por imagen , Microvasos/patología , Microvasos/fisiopatología , Pancreatitis/complicaciones , Pancreatitis/patología , Pancreatitis/fisiopatología , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/patología , Tomografía de Coherencia Óptica/métodos , Agudeza Visual
3.
Phys Rev Lett ; 133(5): 056601, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39159079

RESUMEN

Recent experiments reported that quantum Hall chiral edge state-mediated Josephson junctions (chiral Josephson junctions) could exhibit Fraunhofer oscillations with a periodicity of either h/e [Vignaud et al., Nature (London) 624, 545 (2023)NATUAS0028-083610.1038/s41586-023-06764-4] or h/2e [Amet et al., Science 352, 966 (2016)SCIEAS0036-807510.1126/science.aad6203]. While the h/e-periodic component of the supercurrent had been anticipated theoretically before, the emergence of the h/2e periodicity is still not fully understood. In this Letter, we systematically study the Fraunhofer oscillations of chiral Josephson junctions. In chiral Josephson junctions, the chiral edge states coupled to the superconductors become chiral Andreev edge states. We find that in short junctions, the coupling of the chiral Andreev edge states can trigger the h/2e-magnetic flux periodicity. Our theory resolves the important puzzle concerning the appearance of the h/2e periodicity in chiral Josephson junctions. Furthermore, we explain that when the chiral Andreev edge states couple, a pair of localized Majorana zero modes appear at the ends of the Josephson junction, which are robust and independent of the phase difference between the two superconductors. As the h/2e periodicity and the Majorana zero modes have the same physical origin in the wide junction limit, the Fraunhofer oscillation period could be useful in identifying the regime with Majorana zero modes.

4.
J Am Chem Soc ; 146(33): 23625-23632, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39120638

RESUMEN

The interfacial species-built local environments on Cu surfaces impact the CO2 electroreduction process significantly in producing value-added multicarbon (C2+) products. However, intricate interfacial dynamics leads to a challenge in understanding how these species affect the process. Herein, with ab initio molecular dynamics (AIMD) and finite element method (FEM) simulations, we reveal that the highly concentrated interfacial species, including the *CO, hydroxide, and K+, could synergistically promote the C-C coupling on the one-dimensional (1D) porous hollow structure regulated interfacial environment. The Cu-Ag tandem catalyst was then synthesized with the as-designed structure, exhibiting a high C2+ Faradaic efficiency of 76.0% with a partial current density of 380.0 mA cm-2 in near-neutral electrolytes. Furthermore, in situ Raman spectra validate that the 1D porous structure regulates the concentration of interfacial CO intermediates and ions to increase *CO coverage, local pH value, and ionic field, promoting the CO2-to-C2+ activity. These results provide insights into the design of practical ECR electrocatalysts by regulating interfacial species-induced local environments.

5.
PLoS Pathog ; 20(8): e1012437, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39102432

RESUMEN

The ability of Staphylococcus aureus (S. aureus) to survive within macrophages is a critical strategy for immune evasion, contributing to the pathogenesis and progression of osteomyelitis. However, the underlying mechanisms remain poorly characterized. This study discovered that inhibiting the MEK1/2 pathway reduced bacterial load and mitigated bone destruction in a mouse model of S. aureus osteomyelitis. Histological staining revealed increased phosphorylated MEK1/2 levels in bone marrow macrophages surrounding abscess in the mouse model of S. aureus osteomyelitis. Activation of MEK1/2 pathway and its roles in impairing macrophage bactericidal function were confirmed in primary mouse bone marrow-derived macrophages (BMDMs). Transcriptome analysis and in vitro experiments demonstrated that S. aureus activates the MEK1/2 pathway through EGFR signaling. Moreover, we found that excessive activation of EGFR-MEK1/2 cascade downregulates mitochondrial reactive oxygen species (mtROS) levels by suppressing Chek2 expression, thereby impairing macrophage bactericidal function. Furthermore, pharmacological inhibition of EGFR signaling prevented upregulation of phosphorylated MEK1/2 and restored Chek2 expression in macrophages, significantly enhancing S. aureus clearance and improving bone microstructure in vivo. These findings highlight the critical role of the EGFR-MEK1/2 cascade in host immune defense against S. aureus, suggesting that S. aureus may reduce mtROS levels by overactivating the EGFR-MEK1/2 cascade, thereby suppressing macrophage bactericidal function. Therefore, combining EGFR-MEK1/2 pathway blockade with antibiotics could represent an effective therapeutic approach for the treatment of S. aureus osteomyelitis.


Asunto(s)
Receptores ErbB , MAP Quinasa Quinasa 1 , Macrófagos , Osteomielitis , Infecciones Estafilocócicas , Staphylococcus aureus , Animales , Osteomielitis/microbiología , Osteomielitis/inmunología , Osteomielitis/metabolismo , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/metabolismo , Infecciones Estafilocócicas/microbiología , Ratones , Staphylococcus aureus/inmunología , Receptores ErbB/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/microbiología , MAP Quinasa Quinasa 1/metabolismo , MAP Quinasa Quinasa 2/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Transducción de Señal
6.
Bioelectrochemistry ; 160: 108794, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39142024

RESUMEN

Accurate, convenient, label-free, and cost-effective biomolecules detection platforms are currently in high demand. In this study, we showcased the utilization of electrolyte-gated InGaZnO field-effect transistors (IGZO FETs) featuring a large on-off current ratio of over 106 and a low subthreshold slope of 78.5 mV/dec. In the DNA biosensor, the modification of target DNA changed the effective gate voltage of IGZO FETs, enabling an impressive low detection limit of 0.1 pM and a wide linear detection range from 0.1 pM to 1 µM. This label-free detection method also exhibits high selectivity, allowing for the discrimination of single-base mismatch. Furthermore, the reuse of gate electrodes and channel films offers cost-saving benefits and simplifies device fabrication processes. The electrolyte-gated IGZO FET biosensor presented in this study shows great promise for achieving low-cost and highly sensitive detection of various biomolecules.

7.
Front Psychol ; 15: 1402065, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39108426

RESUMEN

The current study presents the development process and initial validation of the Engagement in Athletic Training Scale (EATS), which was designed to evaluate athletes' engagement in athletic training. In study 1, item generation and initial content validity of the EATS were achieved. In study 2, the factor structure of the EATS was examined using exploratory factor analysis (EFA) and exploratory structural equation modeling (ESEM). Internal consistency reliabilities of the subscales were examined (N = 460). In study 3, factor structure, discriminant validity, internal consistency reliability, and nomological validity of the EATS were further examined in an independent sample (N = 513). Meanwhile, measurement invariance of the EATS across samples (study 2 and study 3) and genders was evaluated. Overall, results from the 3 rigorous studies provided initial psychometric evidence for the 19-item EATS and suggested that the EATS could be used as a valid and reliable measure to evaluate athletes' engagement in athletic training.

8.
Nanoscale ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39129678

RESUMEN

Over the past two decades, significant progress in two-dimensional (2D) materials has invigorated research in condensed matter and material physics in low dimensions. While traditionally studied in three-dimensional systems, magnetism has now been extended to the 2D realm. Recent breakthroughs in 2D magnetism have attracted substantial interest from the scientific community, owing to the stable magnetic order achievable in atomically thin layers of the van der Waals (vdW)-type layered magnetic materials. These advances offer an exciting platform for investigating related phenomena in low dimensions and hold promise for spintronic applications. Consequently, vdW magnetic materials with tunable magnetism have attracted significant attention. Specifically, antiferromagnetic metal thiophosphates MPX3 (M = transition metal, P = phosphorus, X = chalcogen) have been investigated extensively. These materials exhibit long-range magnetic order spanning from bulk to the 2D limit. The magnetism in MPX3 arises from localized moments associated with transition metal ions, making it tunable via substitutions and intercalations. In this review, we focus on such tuning by providing a comprehensive summary of various metal- and chalcogen-substitution and intercalation studies, along with the mechanism of magnetism modulation, and a perspective on the development of this emergent material family.

9.
Nat Prod Res ; : 1-8, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38962949

RESUMEN

The phytochemical investigation on the rhizomes of Paris yunnanensis Franch. resulted in the discovery and characterisation of six compounds, including two new saponins named parisyunnanosides M-N (1-2), and four known ones (3-6). The structures of isolated compounds were determined by spectroscopic data analysis and chemical methods. Compound 2 is a pregnane-type saponin with a special α,ß-unsaturated carboxylic acid moiety at C-17, which is first discovered in genus Paris. The anti-inflammatory activity of the isolated compounds was assessed in vitro. The results demonstrated that compounds 3 and 4 could significantly inhibit the production of NO which was induced by LPS in RAW 264.7 cells with IC50 values of 0.67 ± 0.17 µM and 0.85 ± 0.12 µM, respectively.

10.
Eur J Oncol Nurs ; 72: 102650, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-39018958

RESUMEN

PURPOSE: This study aimed to develop and validate accessible artificial neural network and decision tree models to predict the risk of lower limb lymphedema after cervical cancer surgery. METHODS: We selected 759 patients who underwent cervical cancer surgery at the Hunan Cancer Hospital from January 2010 to January 2020, collecting demographic, behavioral, clinicopathological, and disease-related data. The artificial neural network and decision tree techniques were used to construct prediction models for lower limb lymphedema after cervical cancer surgery. Then, the models' predictive efficacies were evaluated to select the optimal model using several methods, such as the area under the receiver operating characteristic curve and accuracy, sensitivity, and specificity tests. RESULTS: In the training set, the artificial neural network and decision tree model accuracies for predicting lower limb lymphedema after cervical cancer surgery were 99.80% and 88.14%, and the sensitivities 99.50% and 74.01%, respectively; the specificities were 100% and 95.20%, respectively. The area under the receiver operating characteristic curve was 1.00 for the artificial neural network and 0.92 for the decision tree model. In the test set, the artificial neural network and decision tree models' accuracies were 86.70% and 82.02%, and the sensitivities 65.70% and 67.11%, respectively; the specificities were 96.00% and 89.47%, respectively. CONCLUSION: Both models had good predictive efficacy for lower limb lymphedema after cervical cancer surgery. However, the predictive performance and stability were superior in the artificial neural network model than in the decision tree model.

11.
Quant Imaging Med Surg ; 14(7): 4998-5011, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39022287

RESUMEN

Background: As an autoimmune disease, antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) often affects multiple organs, including the ocular system. This study aims to investigate differences in retinal thickness (RT) and retinal superficial vascular density (SVD) between patients with AAV and healthy controls (HCs) using optical coherence tomography angiography (OCTA). Currently, these differences are not clear. Methods: A total of 16 AAV individuals (32 eyes) and 16 HCs (32 eyes) were recruited to this cross-sectional study conducted in the First Affiliated Hospital of Nanchang University from June 2023 to September 2023. The study protocol conformed with the tenets of the Declaration of Helsinki (as revised in 2013). Each image observed by OCTA was divided into 9 regions using the Early Treatment Diabetic Retinopathy Study (ETDRS) subzones as a guide. Results: In the full layer, the RT of AAV patients was found to be significantly reduced in the inner superior (IS, P<0.001), outer superior (OS, P=0.003), inner temporal (IT, P=0.003), and outer temporal (OT, P<0.001) regions; inner RT was significantly lower in the IS (P=0.006), OS (P<0.001), inner nasal (IN, P=0.005), outer nasal (ON, P<0.001), and center (C, P=0.01) regions than that in HCs. Outer RT of AAV patients showed a reduction in the IS (P<0.001), as well as IT (P=0.008), and OT (P<0.001) regions. No statistically significant differences were seen in the different subregions in other different layers (P>0.05). Only the inner inferior (II) and outer inferior (OI) regions of SVD in AAV patients did not differ significantly from controls. All other regions showed a reduction in SVD. The details are as follows: IS (P<0.001), OS (P<0.001), IT (P=0.005), OT (P<0.001), IN (P<0.001), ON (P<0.001), and C (P=0.003). According to receiver operating characteristic (ROC) curve analysis, the full IS region [area under the curve (AUC): 0.8892, 95% confidence interval (CI): 0.8041-0.9742, P<0.001] had the highest diagnostic value for AAV-induced reduction in RT. The IS (AUC: 0.9121, 95% CI: 0.8322-0.9920, P<0.001) region was also the most sensitive to changes in SVD of AAV individuals. In addition, we found that SVD in the IN region (r=-0.4224, 95% CI: -0.6779 to -0.0757, P=0.02) as well as mean visual acuity (r=-0.3922, 95% CI: -0.6579 to -0.0397, P=0.03) of AAV patients were negatively correlated with disease duration. However, we did not find an association between SVD and RT in this study. Conclusions: The findings from OCTA indicated a reduction in RT and SVD among patients with AAV. OCTA allows for the evaluation of AAV-related ocular lesions and holds promise for monitoring of disease progression through regular evaluations.

12.
World J Gastrointest Surg ; 16(6): 1637-1646, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38983358

RESUMEN

BACKGROUND: Early gastric cancer (EGC) is a common malignant tumor of the digestive system, and its lymph node metastasis and survival prognosis have been concerning. By retrospectively analyzing the clinical data of EGC patients, we can better understand the status of lymph node metastasis and its impact on survival and prognosis. AIM: To evaluate the prognosis of EGC patients and the factors that affect lymph node metastasis. METHODS: The clinicopathological data of 1011 patients with EGC admitted to our hospital between January 2015 and December 2023 were collected in a retrospective cohort study. There were 561 males and 450 females. The mean age was 58 ± 11 years. The patient underwent radical gastrectomy. The status of lymph node metastasis in each group was determined according to the pathological examination results of surgical specimens. The outcomes were as follows: (1) Lymph node metastasis in EGC patients; (2) Analysis of influencing factors of lymph node metastasis in EGC; and (3) Analysis of prognostic factors in patients with EGC. Normally distributed measurement data are expressed as mean ± SD, and a t test was used for comparisons between groups. The data are expressed as absolute numbers or percentages, and the chi-square test was used for comparisons between groups. Rank data were compared using a nonparametric rank sum test. A log-rank test and a logistic regression model were used for univariate analysis. A logistic stepwise regression model and a Cox stepwise regression model were used for multivariate analysis. The Kaplan-Meier method was used to calculate the survival rate and construct survival curves. A log-rank test was used for survival analysis. RESULTS: Analysis of influencing factors of lymph node metastasis in EGC. The results of the multifactor analysis showed that tumor length and diameter, tumor site, tumor invasion depth, vascular thrombus, and tumor differentiation degree were independent influencing factors for lymph node metastasis in patients with EGC (odds ratios = 1.80, 1.49, 2.65, 5.76, and 0.60; 95%CI: 1.29-2.50, 1.11-2.00, 1.81-3.88, 3.87-8.59, and 0.48-0.76, respectively; P < 0.05). Analysis of prognostic factors in patients with EGC. All 1011 patients with EGC were followed up for 43 (0-13) months. The 3-year overall survival rate was 97.32%. Multivariate analysis revealed that age > 60 years and lymph node metastasis were independent risk factors for prognosis in patients with EGC (hazard ratio = 9.50, 2.20; 95%CI: 3.31-27.29, 1.00-4.87; P < 0.05). Further analysis revealed that the 3-year overall survival rates of gastric cancer patients aged > 60 years and ≤ 60 years were 99.37% and 94.66%, respectively, and the difference was statistically significant (P < 0.05). The 3-year overall survival rates of patients with and without lymph node metastasis were 95.42% and 97.92%, respectively, and the difference was statistically significant (P < 0.05). CONCLUSION: The lymph node metastasis rate of EGC patients was 23.64%. Tumor length, tumor site, tumor infiltration depth, vascular cancer thrombin, and tumor differentiation degree were found to be independent factors affecting lymph node metastasis in EGC patients. Age > 60 years and lymph node metastasis are independent risk factors for EGC prognosis.

13.
Inorg Chem ; 63(29): 13459-13467, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38982873

RESUMEN

Investigations of transition-metal boride clusters not only lead to novel structures but also provide important information about the metal-boron bonds that are critical to understanding the properties of boride materials. The geometric structures and bonding features of heteronuclear boron-containing transition metal carbonyl cluster cations BM(CO)6+ and BM2(CO)8+ (M = Co, Rh, and Ir) are studied by a combination of the infrared photodissociation spectroscopy and density functional calculations at B3LYP/def2-TZVP level. The completely coordinated BM2(CO)8+ complexes are characterized as a sandwich structure composed of two staggered M(CO)4 fragments and a boron cation, featuring a D3d symmetry and 1Eg electronic ground state as well as metal-anchored carbonyls in an end-on manner. In conjunction with theoretical calculations, multifold metal-boron-metal bonding interactions in BM2(CO)8+ complexes involving the filled d orbitals of the metals and the empty p orbitals of the boron cation were unveiled, namely, one σ-type M-B-M bond and two π-type M-B-M bonds. Accordingly, the BM2(CO)8+ complexes can be described as a linear conjugated (OC)4M═B═M(CO)4 skeleton with a formal B-M bond index of 1.5. The three delocalized d-p-d covalent bonds render compensation for the electron deficiency of the cationic boron center and endow both metal centers with the favorable 18-electron structure, thus contributing much to the overall structural stability of the BM2(CO)8+ cations. As a comparison, the saturated BRh(CO)6+ and BIr(CO)6+ complexes are determined to be a doublet Cs-symmetry structure with an unbridged (OC)2B-M(CO)4 pattern, involving a two-center σ-type (OC)2B → M(CO)4+ dative single bond along with a weak covalent B-M half bond. This work offers important insight into the structure and bonding of late transition metal boride carbonyl cluster cations.

14.
Fitoterapia ; 177: 106136, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39053744

RESUMEN

Global Natural Products Social (GNPS) molecular networking platform was applied to discovery the undescribed compounds from the common marine fungi Aspergillus versicolor CGF9-1-2, ultimately resulting in isolation of four new polyketides, decumbenone E (1), decumbenone F (2), 2'-epi-8-O-methylnidurufin (6), (-)-phomoindene A (7), one new nucleoside, 3-methyl-9-(2-methylbutene)-xanthine (8), and five known analogues. Their structures were elucidated based on 1D/2D NMR spectroscopic and HRESIMS data analyses, meanwhile, the absolute configurations of new compounds were established based on the X-ray crystallographic experiments, as well as the electronic circular dichroism (ECD) analysis. All compounds were predicted pharmaceutical chemistry with ten commonly disease-related proteins by molecular docking. In addition, all compounds against TDP1 were performed in vitro, which was consistent with the docking result, and compound 6 shown a weak inhibitory activity.


Asunto(s)
Antozoos , Aspergillus , Simulación del Acoplamiento Molecular , Aspergillus/química , Antozoos/microbiología , Antozoos/química , Estructura Molecular , Animales , Policétidos/aislamiento & purificación , Policétidos/farmacología , Policétidos/química , China , Productos Biológicos/farmacología , Productos Biológicos/aislamiento & purificación , Productos Biológicos/química , Nucleósidos/aislamiento & purificación , Nucleósidos/química , Nucleósidos/farmacología
15.
Angew Chem Int Ed Engl ; : e202409763, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38954763

RESUMEN

Developing non-platinum group metal catalysts for the sluggish hydrogen oxidation reaction (HOR) is critical for alkaline fuel cells. To date, Ni-based materials are the most promising candidates but still suffer from insufficient performance. Herein, we report an unconventional hcp/fcc Ni (u-hcp/fcc Ni) heteronanocrystal with multiple epitaxial hcp/fcc heterointerfaces and coherent twin boundaries, generating rugged surfaces with plenty of asymmetric convex sites. Systematic analyses discover that such convex sites enable the adsorption of *H in unusual bridge positions with weakened binding energy, circumventing the over-strong *H adsorption on traditional hollow positions, and simultaneously stabilizing interfacial *H2O. It thus synergistically optimizes the HOR thermodynamic process as well as reduces the kinetic barrier of the rate-determining Volmer step. Consequently, the developed u-hcp/fcc Ni exhibits the top-rank alkaline HOR activity with a mass activity of 40.6 mA mgNi-1 (6.3 times higher than fcc Ni control) together with superior stability and high CO-tolerance. These results provide a paradigm for designing high-performance catalysts by shifting the adsorption state of intermediates through configuring surface sites.

16.
Plants (Basel) ; 13(13)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38999715

RESUMEN

Stripe rust (Puccinia striiformis West. f.sp. tritici, Pst) is a destructive disease that seriously threatens wheat production globally. Exploring novel resistance genes for use in wheat breeding is an urgent need, as continuous Pst evolution frequently leads to a breakdown of host resistance. Here, we identified a set of wheat-Dasypyrum villosum 01I139 (V#6) disomic introgression lines for the purpose of determining their responses to a mixture of Pst isolates CYR32, CYR33 and CYR34 at both seedling and adult-plant stages. The results showed that all introgression lines exhibited high susceptibility at the seedling stage, with infection-type (IT) scores in the range of 6-8, whereas, for chromosomes 5V#6 and 7V#6, disomic addition lines NAU5V#6-1 and NAU7V#6-1 displayed high resistance at the adult-plant stage, indicating that adult-plant resistance (APR) genes were located on them. Further, in order to transfer the stripe-rust resistance on chromosome 7V#6, four new wheat-D. villosum introgression lines were identified, by the use of molecular cytogenetic approaches, from the self-pollinated seeds of 7D and 7V#6, in double monosomic line NAU7V#6-2. Among them, NAU7V#6-3 and NAU7V#6-4 were t7V#6L and t7V#6S monosomic addition lines, and NAU7V#6-5 and NAU7V#6-6 were homozygous T7DS·7V#6L and T7DL·7V#6S whole-arm translocation lines. Stripe-rust tests and genetic analyses of chromosome 7V#6 introgression lines revealed a dominant APR gene designated as Yr7VS on the chromosome arm 7V#6S. Comparison with the homozygous T7DL·7V#6S translocation line and the recurrent parent NAU0686 showed no significant differences in yield-related traits. Thus, T7DL·7V#6S whole-arm translocation with the APR gene Yr7VS provided a valuable germplasm for breeding for resistance.

17.
Fitoterapia ; 177: 106104, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38950637

RESUMEN

Four undescribed polyketides, beshanzones A (1) and B (2) as well as beshanhexanols A (3) and B (4), along with three known ones (5-7) were isolated from the rice fermentation of two endophytic fungi associated with the critically endangered Chinese endemic conifer Abies beshanzuensis. γ-Butyrolactone derivatives 1, 2, and 5 were isolated from Phomopsis sp. BSZ-AZ-2, an interesting strain that drawn our attention this time. The cyclohexanol derivatives 3, 4, 6, and 7 were obtained during a follow-up investigation on Penicillium commune BSZ-P-4-1. The chemical structures including absolute configurations of compounds 1-4 were determined by spectroscopic methods, Mo2(OAc)4 induced electronic circular dichroism (IECD), GIAO NMR calculations and DP4+ probability analyses. In particular, compound 2 contains a novel 5/5 bicyclic ring system, which might be biogenetically derived from the known compound 5 through hydrolysis followed by an Aldol reaction. All isolates were evaluated for their antimicrobial activities against a small panel of bacterial and fungal pathogens. Compounds 6 and 7 showed moderate inhibitory activities against Candida albicans, with MIC values of 16 and 32 µg/mL, respectively.


Asunto(s)
Abies , Especies en Peligro de Extinción , Endófitos , Policétidos , Endófitos/química , Policétidos/farmacología , Policétidos/aislamiento & purificación , Policétidos/química , Estructura Molecular , China , Abies/química , Phomopsis/química , Pruebas de Sensibilidad Microbiana , Penicillium/química , Bacterias/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación , 4-Butirolactona/análogos & derivados , 4-Butirolactona/aislamiento & purificación , 4-Butirolactona/farmacología , 4-Butirolactona/química
18.
Phytochemistry ; 226: 114221, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39002688

RESUMEN

An extensive phytochemical investigation on the EtOAc-soluble fraction of the 90% MeOH extract from the twigs and needles of the 'vulnerable' Chinese endemic conifer Tsuga forrestii (Forrest's hemlock) led to the isolation and characterization of 50 structurally diverse diterpenoids, including 15 unreported C-18 carboxylated ones (tsugaforrestiacids A-O, 1-15, resp.). Among them, compounds 1-7 are abieten-18-oic acids, compound 8 is an abieten-18-succinate, and compounds 10-12 are podocarpen-18-oic acids, whereas compounds 13-15 are pimarane-type, isopimarane-type, and totarane-type diterpenoid acids, respectively. Their structures and absolute configurations were determined by a combination of spectroscopic methods, GIAO NMR calculations and DP4+ probability analyses, electronic circular dichroism (ECD) data, and single crystal X-ray diffraction analyses. All the isolates were evaluated for their inhibitory activities against the ATP-citrate lyase (ACL), a key enzyme in cellular metabolism. Tsugaforrestiacids E (5) and H (8) were found to have significant inhibitory effects against ACL, with IC50 values of 5.3 and 6.2 µM, respectively. The interactions of the bioactive molecules with the ACL enzyme were examined by molecular docking studies. The isolated diterpenoids also provide chemotaxonomic evidence to support the delimitation of Tsuga from its closest sister group (Nothotsuga). The above findings highlight the importance of protecting plant species with unique and diverse secondary metabolites, which may be potential sources of new therapeutic agents for the treating ACL-associated diseases.


Asunto(s)
ATP Citrato (pro-S)-Liasa , Diterpenos , Fitoquímicos , Diterpenos/química , Diterpenos/farmacología , Diterpenos/aislamiento & purificación , ATP Citrato (pro-S)-Liasa/antagonistas & inhibidores , ATP Citrato (pro-S)-Liasa/metabolismo , Fitoquímicos/farmacología , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , China , Estructura Molecular , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Especies en Peligro de Extinción , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad , Hojas de la Planta/química
19.
Environ Res ; 261: 119707, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39084507

RESUMEN

Soil salinization poses a significant global challenge, exerting adverse effects on both agriculture and ecosystems. Planting halophytes has the potential ability to improve saline-alkali land and enhance ecosystem multifunctionality (EMF). However, it remains unclear which halophytes are effective in improving saline-alkali land and what impact they have on the rhizosphere microbial communities and EMF. In this study, we evaluated the Na+ absorption capability of five halophytes (Grubovia dasyphylla, Halogeton glomeratus, Suaeda salsa, Bassia scoparia, and Reaumuria songarica) and assessed their rhizosphere microbial communities and EMF. The results showed that S. salsa possessed the highest shoot (3.13 mmol g-1) and root (0.92 mmol g-1) Na+ content, and its soil Na+ absorption, along with B. scoparia, was significantly higher than that of other plants. The soil pH, salinity, and Na+ content of the halophyte rhizospheres decreased by 6.21%, 23.49%, and 64.29%, respectively, when compared to the bulk soil. Extracellular enzymes in the halophyte rhizosphere soil, including α-glucosidase, ß-glucosidase, ß-1,4-N-acetyl-glucosaminidase, neutral phosphatase, and alkaline phosphatase, increased by 70.1%, 78.4%, 38.5%, 79.1%, and 64.9%, respectively. Furthermore, the halophyte rhizosphere exhibited higher network complexity of bacteria and fungi and EMF than bulk soil. The relative abundance of the dominant phyla Proteobacteria, Firmicutes, and Ascomycota in the halophyte rhizosphere soil increased by 9.4%, 8.3%, and 22.25%, respectively, and showed higher microbial network complexity compared to the bulk soil. Additionally, keystone taxa, including Muricauda, Nocardioides, and Pontibacter, were identified with notable effects on EMF. This study confirmed that euhalophytes are the best choice for saline-alkali land restoration. These findings provided a theoretical basis for the sustainable use of saline-alkali cultivated land.

20.
CNS Neurosci Ther ; 30(7): e14870, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39049714

RESUMEN

AIMS: Traumatic brain injury (TBI) stands as a significant concern in public health, frequently leading to enduring neurological deficits. Long non-coding RNA H19 (lncRNA H19) exerts a potential regulator role in the pathology of brain injury. This study investigates the effects of lncRNA H19 knockdown (H19-KD) on the pathophysiology of TBI and its potential neuroprotective mechanisms. METHODS: Controlled cortical impact was employed to establish a stable TBI mouse model. The expression levels of various genes in perilesional cortex and striatum tissue after TBI was detected by RT-qPCR. AAV9-shRNA-H19 was injected into the lateral ventricle of mice to knockdown the expression of lncRNA H19. Various behavioral tests were performed to evaluate sensorimotor and cognitive functions after TBI. Immunofluorescence and Nissl staining were performed to assess brain tissue damage and neuroinflammation. The Nrf2 and HO-1 expression was performed by Western blot. RESULTS: After TBI, the expression of lncRNA H19 was elevated in perilesional tissue and gradually reverted to baseline. Behavioral tests demonstrated that H19-KD significantly promoted the recovery of sensorimotor and cognitive functions after TBI. Besides, H19-KD reduced brain tissue loss, preserved neuronal integrity, and ameliorated white matter damage at the histological level. In addition, H19-KD restrained the pro-inflammatory and facilitated anti-inflammatory phenotypes of microglia/macrophages, attenuating the neuroinflammatory response after TBI. Furthermore, H19-KD promoted activation of the Nrf2/HO-1 axis after TBI, while suppression of Nrf2 partially abolished the neuroprotective effect. CONCLUSION: H19-KD exerts neuroprotective effects after TBI in mice, partially mediated by the activation of the Nrf2/HO-1 axis.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2 , ARN Largo no Codificante , Recuperación de la Función , Animales , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Lesiones Traumáticas del Encéfalo/patología , Lesiones Traumáticas del Encéfalo/metabolismo , Lesiones Traumáticas del Encéfalo/genética , Ratones , Recuperación de la Función/fisiología , Masculino , Técnicas de Silenciamiento del Gen/métodos , Hemo-Oxigenasa 1/metabolismo , Proteínas de la Membrana
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