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1.
Proc Natl Acad Sci U S A ; 121(35): e2317182121, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39172793

RESUMEN

From microbes to humans, organisms perform numerous tasks for their survival, including food acquisition, migration, and reproduction. A complex biological task can be performed by either an autonomous organism or by cooperation among several specialized organisms. However, it remains unclear how autonomy and cooperation evolutionarily switch. Specifically, it remains unclear whether and how cooperative specialists can repair deleted genes through direct genetic exchange, thereby regaining metabolic autonomy. Here, we address this question by experimentally evolving a mutualistic microbial consortium composed of two specialists that cooperatively degrade naphthalene. We observed that autonomous genotypes capable of performing the entire naphthalene degradation pathway evolved from two cooperative specialists and dominated the community. This evolutionary transition was driven by the horizontal gene transfer (HGT) between the two specialists. However, this evolution was exclusively observed in the fluctuating environment alternately supplied with naphthalene and pyruvate, where mutualism and competition between the two specialists alternated. The naphthalene-supplied environment exerted selective pressure that favors the expansion of autonomous genotypes. The pyruvate-supplied environment promoted the coexistence and cell density of the cooperative specialists, thereby increasing the likelihood of HGT. Using a mathematical model, we quantitatively demonstrate that environmental fluctuations facilitate the evolution of autonomy through HGT when the relative growth rate and carrying capacity of the cooperative specialists allow enhanced coexistence and higher cell density in the competitive environment. Together, our results demonstrate that cooperative specialists can repair deleted genes through a direct genetic exchange under specific conditions, thereby regaining metabolic autonomy.


Asunto(s)
Naftalenos , Naftalenos/metabolismo , Transferencia de Gen Horizontal , Evolución Biológica , Simbiosis , Consorcios Microbianos/genética , Consorcios Microbianos/fisiología , Genotipo
2.
Asian J Androl ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39119639

RESUMEN

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a complex disease that is often accompanied by mental health disorders. However, the potential mechanisms underlying the heterogeneous clinical presentation of CP/CPPS remain uncertain. This study analyzed widely targeted metabolomic data of expressed prostatic secretions (EPS) and plasma to reveal the underlying pathological mechanisms of CP/CPPS. A total of 24 CP/CPPS patients from The Second Nanning People's Hospital (Nanning, China), and 35 asymptomatic control individuals from First Affiliated Hospital of Guangxi Medical University (Nanning, China) were enrolled. The indicators related to CP/CPPS and psychiatric symptoms were recorded. Differential analysis, coexpression network analysis, and correlation analysis were performed to identify metabolites that were specifically altered in patients and associated with various phenotypes of CP/CPPS. The crucial links between EPS and plasma were further investigated. The metabolomic data of EPS from CP/CPPS patients were significantly different from those from control individuals. Pathway analysis revealed dysregulation of amino acid metabolism, lipid metabolism, and the citrate cycle in EPS. The tryptophan metabolic pathway was found to be the most significantly altered pathway associated with distinct CP/CPPS phenotypes. Moreover, the dysregulation of tryptophan and tyrosine metabolism and elevation of oxidative stress-related metabolites in plasma were found to effectively elucidate the development of depression in CP/CPPS. Overall, metabolomic alterations in the EPS and plasma of patients were primarily associated with oxidative damage, energy metabolism abnormalities, neurological impairment, and immune dysregulation. These alterations may be associated with chronic pain, voiding symptoms, reduced fertility, and depression in CP/CPPS. This study provides a local-global perspective for understanding the pathological mechanisms of CP/CPPS and offers potential diagnostic and therapeutic targets.

3.
Front Neurosci ; 18: 1424316, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39148521

RESUMEN

Chemical Exchange Saturation Transfer (CEST) is a technique that uses specific off-resonance saturation pulses to pre-saturate targeted substances. This process influences the signal intensity of free water, thereby indirectly providing information about the pre-saturated substance. Among the clinical applications of CEST, Amide Proton Transfer (APT) is currently the most well-established. APT can be utilized for the preoperative grading of gliomas. Tumors with higher APTw signals generally indicate a higher likelihood of malignancy. In predicting preoperative molecular typing, APTw values are typically lower in tumors with favorable molecular phenotypes, such as isocitrate dehydrogenase (IDH) mutations, compared to IDH wild-type tumors. For differential diagnosis, the average APTw values of meningiomas are significantly lower than those of high-grade gliomas. Various APTw measurement indices assist in distinguishing central nervous system lesions with similar imaging features, such as progressive multifocal leukoencephalopathy, central nervous system lymphoma, solitary brain metastases, and glioblastoma. Regarding prognosis, APT effectively differentiates between tumor recurrence and treatment effects, and also possesses predictive capabilities for overall survival (OS) and progression-free survival (PFS).

4.
J Mol Med (Berl) ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39158595

RESUMEN

Crouzon syndrome (CS), a syndromic craniosynostosis, is a craniofacial developmental deformity caused by mutations in fibroblast growth factor receptor 2 (FGFR2). Previous CS mouse models constructed using traditional gene editing techniques faced issues such as low targeting efficiency, extended lineage cycles, and inconsistent and unstable phenotypes. In this study, a CRISPR/Cas9-mediated strategy was employed to induce a functional augmentation of the Fgfr2 point mutation in mice. Various techniques, including bone staining, micro-CT, histological methods, and behavioral experiments, were employed to systematically examine and corroborate phenotypic disparities between mutant mice (Fgfr2C361Y/+) and their wild-type littermates. Confirmed via PCR-Sanger sequencing, we successfully induced the p.Cys361Tyr missense mutation in the Fgfr2 IIIc isoform of the extracellular domain (corresponding to the p.Cys342Tyr mutation in humans) based on Fgfr2-215 transcript (ENSMUST00000122054.8). Fgfr2C361Y/+ mice exhibited characteristics consistent with the phenotypic features associated with CS, including skull-vault craniosynostosis, skull deformity, shallow orbits accompanied by exophthalmos, midface hypoplasia with malocclusion, and shortened skull base, notably without any apparent limb defects. Furthermore, mutant mice displayed behavioral abnormalities encompassing deficits in learning and memory, social interaction, and motor dysfunction, without anxiety-related disorders. Histopathological examination of the hippocampal region revealed structural abnormalities, suggesting possible brain development impairment secondary to craniosynostosis. In conclusion, we constructed a novel gene-edited Fgfr2C361Y/+ mice strain based on CRISPR/Cas9, which displayed skull and behavioral abnormalities, serving as a new model for studying genetic molecular mechanisms and exploring treatments for CS. KEY MESSAGES: CRISPR/Cas9 crafted a Crouzon model by enhancing Fgfr2-C361Y in mice. Fgfr2C361Y/+ mice replicate CS phenotypes-craniosynostosis and midface anomalies. Mutant mice show diverse behavioral abnormalities, impacting learning and memory. Fgfr2C361Y/+ mice offer a novel model for cranial suture studies and therapeutic exploration.

5.
Nat Commun ; 15(1): 6789, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39117673

RESUMEN

Oil reservoirs, being one of the significant subsurface repositories of energy and carbon, host diverse microbial communities affecting energy production and carbon emissions. Viruses play crucial roles in the ecology of microbiomes, however, their distribution and ecological significance in oil reservoirs remain undetermined. Here, we assemble a catalogue encompassing viral and prokaryotic genomes sourced from oil reservoirs. The catalogue comprises 7229 prokaryotic genomes and 3,886 viral Operational Taxonomic Units (vOTUs) from 182 oil reservoir metagenomes. The results show that viruses are widely distributed in oil reservoirs, and 85% vOTUs in oil reservoir are detected in less than 10% of the samples, highlighting the heterogeneous nature of viral communities within oil reservoirs. Through combined microcosm enrichment experiments and bioinformatics analysis, we validate the ecological roles of viruses in regulating the community structure of sulfate reducing microorganisms, primarily through a virulent lifestyle. Taken together, this study uncovers a rich diversity of viruses and their ecological functions within oil reservoirs, offering a comprehensive understanding of the role of viral communities in the biogeochemical cycles of the deep biosphere.


Asunto(s)
Biodiversidad , Metagenoma , Yacimiento de Petróleo y Gas , Virus , Yacimiento de Petróleo y Gas/virología , Yacimiento de Petróleo y Gas/microbiología , Virus/genética , Virus/clasificación , Virus/aislamiento & purificación , Metagenoma/genética , Microbiota/genética , Genoma Viral/genética , Filogenia , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación , Metagenómica
6.
Chem Soc Rev ; 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39143899

RESUMEN

With the increasing demand for energy and the climate challenges caused by the consumption of traditional fuels, there is an urgent need to accelerate the adoption of green and sustainable energy conversion and storage technologies. The integration of flexible thermoelectrics with other various energy conversion technologies plays a crucial role, enabling the conversion of multiple forms of energy such as temperature differentials, solar energy, mechanical force, and humidity into electricity. The development of these technologies lays the foundation for sustainable power solutions and promotes research progress in energy conversion. Given the complexity and rapid development of this field, this review provides a detailed overview of the progress of multifunctional integrated energy conversion and storage technologies based on thermoelectric conversion. The focus is on improving material performance, optimizing the design of integrated device structures, and achieving device flexibility to expand their application scenarios, particularly the integration and multi-functionalization of wearable energy conversion technologies. Additionally, we discuss the current development bottlenecks and future directions to facilitate the continuous advancement of this field.

7.
ACS Appl Mater Interfaces ; 16(32): 42597-42607, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39102741

RESUMEN

Field-effect transistor (FET) biosensors based on two-dimensional (2D) materials are highly sought after for their high sensitivity, label-free detection, fast response, and ease of on-chip integration. However, the subthreshold swing (SS) of FETs is constrained by the Boltzmann limit and cannot fall below 60 mV/dec, hindering sensor sensitivity enhancement. Additionally, the gate-leakage current of 2D material biosensors in liquid environments significantly increases, adversely affecting the detection accuracy and stability. Based on the principle of negative capacitance, this paper presents for the first time a two-dimensional material WSe2 negative capacitance field-effect transistor (NCFET) with a minimum subthreshold swing of 56 mV/dec in aqueous solution. The NCFET shows a significantly improved biosensor function. The pH detection sensitivity of the NCFET biosensor reaches 994 pH-1, nearly an order of magnitude higher than that of the traditional two-dimensional WSe2 FET biosensor. The Al2O3/HfZrO (HZO) bilayer dielectric in the NCFET not only contributes to negative capacitance characteristics in solution but also significantly reduces the leakage in solution. Utilizing an enzyme catalysis method, the WSe2 NCFET biosensor demonstrates a specific detection of glucose molecules, achieving a high sensitivity of 4800 A/A in a 5 mM glucose solution and a low detection limit (10-9 M). Further experiments also exhibit the ability of the biosensor to detect glucose in sweat.


Asunto(s)
Técnicas Biosensibles , Capacidad Eléctrica , Glucosa , Transistores Electrónicos , Técnicas Biosensibles/instrumentación , Glucosa/análisis , Óxido de Aluminio/química , Hafnio/química , Concentración de Iones de Hidrógeno , Óxidos
8.
Front Neurol ; 15: 1369414, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39108659

RESUMEN

Objective: To explore the spatial relationship between A1 segment proximal anterior cerebral artery aneurysms and their main trunks, classify them anatomically and develop targeted treatment strategies. Methods: This single-center retrospective analysis involved 39 patients diagnosed with aneurysms originating from the proximal of A1 segment of the anterior cerebral artery (2014-2023). Classify the patient's aneurysm into 5 types based on the location of the neck involving the carrier artery and the spatial relationship and projection direction of the aneurysm body with the carrier artery, and outcomes from treatment methods were compared. Results: Among 39 aneurysms, 18 cases underwent endovascular intervention treatment, including 6 cases of stent assisted embolization, 1 case of flow-diverter embolization, 5 cases of balloon assisted embolization, and 6 cases of simple coiling. At discharged, the mRS score of all endovascularly treated patients was 0, and the GOS score was 5 at 6 months after discharge. At discharge, the mRS score of microsurgical clipping treated patients was 0 for 15 cases, 3 for 1 case, 4 for 1 case and 5 for 2 cases. Six months after discharge, the GOS score was 5 for 16 cases, 4 for 2 cases, 3 for 2 cases, and 1 for 1 case. GOS outcomes at 6 months were better for endovascularly treated patients (p = 0.047). Conclusion: Results showed better outcomes for the endovascular treatment group compared to microsurgical clipping at 6 months after surgery. The anatomical classification of aneurysms in this region may be of help to develop effective treatment strategies.

9.
Eur J Radiol ; 179: 111664, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39121745

RESUMEN

OBJECTIVES: To investigate whether high concentration iodinated contrast media (CM), compared with low concentration CM, could reduce pain and discomfort levels in patients who had level II and III venous conditions. METHODS: This prospective, single-center study enrolled patients who had level II and III venous conditions and underwent abdominal contrast-enhanced CT scan between July 2021 and February 2022. The venous condition to establish peripheral venous access for CM injection was graded using the Intravenous Access Scoring system, of which level II and III indicated poor venous condition and difficult venous access. Patients received iomeprol 400 in high concentration group and ioversol 320 in low group at an identical iodine delivery rate of 1.12 gI/s. The primary outcomes were pain and comfort levels. The secondary outcomes included adverse events and image quality. Patients rated pain intensity via Numerical Rating Scale and comfort level via Visual Analogue Scale with higher scores indicating higher levels of pain and discomfort. Quantitative and qualitative image assessment were compared between two groups. Continuous variables were compared using Student's t test or Mann-Whitney U test. Categorical variables were compared using χ2 test, χ2 test for trend or Fisher's exact test. RESULTS: A total of 206 patients (mean age, 60.13 ± 12.14 years; 81 males) were included with 99 in the high concentration group and 107 in the low concentration group. The high group had significantly lower pain scores (median 1 [IQR: 0-2] vs 2 (IQR 2-4), p < 0.001) and comfort scores (1 [IQR: 0-3] vs 3 [IQR: 2-5], p < 0.001) than the low group. Incidence of CM extravasation did not significantly differ (1.0 % vs 4.5 %, p = 0.214). No hypersensitivity reaction was observed. Qualitative assessment showed higher clarity scores of intrahepatic hepatic artery and portal vein in the high group. Quantitative assessment results were comparable between two groups. CONCLUSION: High concentration iodinated CM could lower pain intensity and improve comfort levels without comprising image quality of CT scan. High concentration CM is a preferable choice in patients with poor venous conditions during contrast-enhanced CT scan.

10.
Neuropharmacology ; 259: 110100, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39117105

RESUMEN

Stinels are a novel class of N-methyl-d-aspartate glutamate receptor (NMDAR) positive allosteric modulators. We explored mechanism of action and NR2 subtype specificity of the stinel zelquistinel (ZEL) in HEK 293 cells expressing recombinant NMDARs. ZEL potently enhanced NMDAR current at NR2A (EC50 = 9.9 ± 0.5 nM) and NR2C-containing (EC50 = 9.7 ± 0.6 nM) NMDARs, with a larger ceiling enhancement at NR2B-NMDAR (EC50 = 35.0 ± 0.7 nM), while not affecting NR2D-containing NMDARs. In cells expressing NR2A and NR2C-containing NMDARs, ZEL exhibited an inverted-U dose-response relation, with a low concentration enhancement and high concentration suppression of NMDAR currents. Extracellular application of ZEL potentiated NMDAR receptor activity via prolongation of NMDAR currents. Replacing the slow Ca2+ intracellular chelator EGTA with the fast chelator BAPTA blocked ZEL potentiation of NMDARs, suggesting an action on intracellular Ca2+-calmodulin-dependent inactivation (CDI). Consistent with this mechanism of action, removal of the NR1 intracellular C-terminus, or intracellular infusion of a calmodulin blocking peptide, blocked ZEL potentiation of NMDAR current. In contrast, BAPTA did not prevent high-dose suppression of current, indicating this effect has a different mechanism of action. These data indicate ZEL is a novel positive allosteric modulator that binds extracellularly and acts through a unique long-distance mechanism to reduce NMDAR CDI, eliciting enhancement of NMDAR current. The critical role that NMDARs play in long-term, activity-dependent synaptic plasticity, learning, memory and cognition, suggests dysregulation of CDI may contribute to psychiatric disorders such as depression, schizophrenia and others, and that the stinel class of drugs can restore NMDAR-dependent synaptic plasticity by reducing activity-dependent CDI.

11.
Adv Sci (Weinh) ; : e2310244, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39099429

RESUMEN

The most pronounced neuropathological feature of Parkinson's disease (PD) is the loss of dopamine (DA) neurons in the substantia nigra compacta (SNc), which depletes striatal DA. Hypothalamic oxytocin is found to be reduced in PD patients and closely interacts with the DA system, but the role of oxytocin in PD remains unclear. Here, the disturbances of endogenous oxytocin level and the substantia nigra (SN) oxytocin receptor expression in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model is observed, correlated with the striatal tyrosine hydroxylase (TH) expression reduction. Killing/silencing hypothalamic oxytocin neurons aggravates the vulnerability of nigrostriatal DA signal to MPTP, whereas elevating oxytocin level by intranasal delivery or microinjecting into the SN promotes the resistance. In addition, knocking out SN oxytocin receptors induces the time-dependent reductions of SNc DA neurons, striatal TH expression, and striatal DA level by increasing neuronal excitotoxicity. These results further uncover that oxytocin dampens the excitatory synaptic inputs onto DA neurons via activating oxytocin receptor-expressed SN GABA neurons, which target GABA(B) receptors expressed in SNc DA neuron-projecting glutamatergic axons, to reduce excitotoxicity. Thus, besides the well-known prosocial effect, oxytocin acts as a key endogenous factor in protecting the nigrostriatal DA system.

12.
Se Pu ; 42(7): 702-710, 2024 Jul.
Artículo en Chino | MEDLINE | ID: mdl-38966978

RESUMEN

Organic acid metabolites exhibit acidic properties. These metabolites serve as intermediates in major carbon metabolic pathways and are involved in several biochemical pathways, including the tricarboxylic acid (TCA) cycle and glycolysis. They also regulate cellular activity and play crucial roles in epigenetics, tumorigenesis, and cellular signal transduction. Knowledge of the binding proteins of organic acid metabolites is crucial for understanding their biological functions. However, identifying the binding proteins of these metabolites has long been a challenging task owing to the transient and weak nature of their interactions. Moreover, traditional methods are unsuitable for the structural modification of the ligands of organic acid metabolites because these metabolites have simple and similar structures. Even minor structural modifications can significantly affect protein interactions. Thermal proteome profiling (TPP) provides a promising avenue for identifying binding proteins without the need for structural modifications. This approach has been successfully applied to the identification of the binding proteins of several metabolites. In this study, we investigated the binding proteins of two TCA cycle intermediates, i.e., succinate and fumarate, and lactate, an end-product of glycolysis, using the matrix thermal shift assay (mTSA) technique. This technique involves combining single-temperature (52 ℃) TPP and dose-response curve analysis to identify ligand-binding proteins with high levels of confidence and determine the binding affinity between ligands and proteins. To this end, HeLa cells were lysed, followed by protein desalting to remove endogenous metabolites from the cell lysates. The desalted cell lysates were treated with fumarate or succinate at final concentrations of 0.004, 0.04, 0.4, and 2 mmol/L in the experimental groups or 2 mmol/L sodium chloride in the control group. Considering that the cellular concentration of lactate can be as high as 2-30 mmol/L, we then applied lactate at final concentrations of 0.2, 1, 5, 10, and 25 mmol/L in the experimental groups or 25 mmol/L sodium chloride in the control group. Using high-sensitivity mass spectrometry coupled with data-independent acquisition (DIA) quantification, we quantified 5870, 5744, and 5816 proteins in succinate, fumarate, and lactate mTSA experiments, respectively. By setting stringent cut-off values (i.e., significance of changes in protein thermal stability (p-value)<0.001 and quality of the dose-response curve fitting (square of Pearson's correlation coefficient, R2)>0.95), multiple binding proteins for these organic acid metabolites from background proteins were confidently determined. Several known binding proteins were identified, notably fumarate hydratase (FH) as a binding protein for fumarate, and α-ketoglutarate-dependent dioxygenase (FTO) as a binding protein for both fumarate and succinate. Additionally, the affinity data for the interactions between these metabolites and their binding proteins were obtained, which closely matched those reported in the literature. Interestingly, ornithine aminotransferase (OAT), which is involved in amino acid biosynthesis, and 3-mercaptopyruvate sulfurtransferase (MPST), which acts as an antioxidant in cells, were identified as lactate-binding proteins. Subsequently, an orthogonal assay technique developed in our laboratory, the solvent-induced precipitation (SIP) technique, was used to validate the mTSA results. SIP identified OAT as the top target candidate, validating the mTSA-based finding that OAT is a novel lactate-binding protein. Although MPST was not identified as a lactate-binding protein by SIP, statistical analysis of MPST in the mTSA experiments with 10 or 25 mmol/L lactate revealed that MPST is a lactate-binding protein with a high level of confidence. Peptide-level empirical Bayes t-tests combined with Fisher's exact test also supported the conclusion that MPST is a lactate-binding protein. Lactate is structurally similar to pyruvate, the known binding protein of MPST. Therefore, assuming that lactate could potentially occupy the binding site of pyruvate on MPST. Overall, the novel binding proteins identified for lactate suggest their potential involvement in amino acid synthesis and redox balance regulation.


Asunto(s)
Ciclo del Ácido Cítrico , Humanos , Células HeLa , Ácido Succínico/metabolismo , Ácido Succínico/química , Fumaratos/metabolismo , Fumaratos/química
14.
Int J Ophthalmol ; 17(7): 1370-1374, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39026920

RESUMEN

Among refractive errors, astigmatism is the most common optical aberration, where refraction changes in different meridians of the eye. It causes blurred vision at any distance and includes corneal, lenticular, and retinal astigmatism. Cataract surgery used to cause a progressive increase in the pre-exisiting corneal astigmatism because of creating a surgically induced astigmatism, for example, a large size surgery incision. The development of surgical techniques during last decades has made cataract surgery interchange to treat preoperative corneal astigmatism at time of surgery. Nowadays, three surgical approaches can be used. By placing a sutureless clear corneal incision on the steep meridian of the cornea, a preoperative corneal astigmatism less than 1.0 D can be corrected. Single or paired peripheral corneal relaxing incisions (PCRIs) provide 1.0-3.0 D corneal astigmatism correction. PCRIs are typically used for treating 1.0-1.5 D of regular corneal astigmatism, if more than 2.0 D, the risk of overcorrection and irregular astigmatism is increased. When toric intraocular lenses (IOLs) are unavailable in markets, PCRIs are still a reasonable option for patients with up to 3.0 D of pre-existing corneal astigmatism. Toric IOLs implantation can correct 1.0-4.5 D of corneal astigmatism. Several IOLs are approved to correct a high degree of corneal astigmatism with cylinder power up to 12.0 D. These approaches can be used alone or in combination.

15.
Nat Commun ; 15(1): 6074, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025911

RESUMEN

One-dimensional metallic transition-metal chalcogenide nanowires (TMC-NWs) hold promise for interconnecting devices built on two-dimensional (2D) transition-metal dichalcogenides, but only isotropic growth has so far been demonstrated. Here we show the direct patterning of highly oriented Mo6Te6 NWs in 2D molybdenum ditelluride (MoTe2) using graphite as confined encapsulation layers under external stimuli. The atomic structural transition is studied through in-situ electrical biasing the fabricated heterostructure in a scanning transmission electron microscope. Atomic resolution high-angle annular dark-field STEM images reveal that the conversion of Mo6Te6 NWs from MoTe2 occurs only along specific directions. Combined with first-principles calculations, we attribute the oriented growth to the local Joule-heating induced by electrical bias near the interface of the graphite-MoTe2 heterostructure and the confinement effect generated by graphite. Using the same strategy, we fabricate oriented NWs confined in graphite as lateral contact electrodes in the 2H-MoTe2 FET, achieving a low Schottky barrier of 11.5 meV, and low contact resistance of 43.7 Ω µm at the metal-NW interface. Our work introduces possible approaches to fabricate oriented NWs for interconnections in flexible 2D nanoelectronics through direct metal phase patterning.

16.
Angew Chem Int Ed Engl ; : e202408379, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970405

RESUMEN

Formamide (HCONH2) plays a pivotal role in the manufacture of a diverse array of chemicals, fertilizers, and pharmaceuticals. Photocatalysis holds great promise for green fabrication of carbon-nitrogen (C-N) compounds owing to its environmental friendliness and mild redox capability. However, the selective formation of the C-N bond presents a significant challenge in the photocatalytic synthesis of C-N compounds. This work developed a photocatalytic radical coupling method for the formamide synthesis from co-oxidation of ammonia (NH3) and methanol (CH3OH). An exceptional formamide yield rate of 5.47 ± 0.03 mmol·gcat-1·h-1 (911.87 ± 0.05 mmol·gBi-1·h-1) was achieved over atomically dispersed Bi sites (BiSAs) on TiO2. An accumulation of 45.0 mmol·gcat-1 (0.2 g·gcat-1) of formamide was achieved after long-term illumination, representing the highest level of photocatalytic C-N compounds synthesis. The critical C-N coupling for formamide formation originated from the "σ-σ" interaction between electrophilic ●CH2OH with nucleophilic ●NH2 radical. The  BiSAs sites facilitated the electron transfer between reactants and photocatalysts and enhanced the nucleophilic attack of â—NH2 radical at the â—CH2OH radical, thereby advancing the selective C-N bond formation. This work deepens the understanding of the C-N coupling mechanism and offers an alternative and intriguing photocatalytic approach for the efficient and sustainable production of C-N compounds.

17.
Int J Med Sci ; 21(9): 1604-1611, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39006846

RESUMEN

Purpose: To investigate morphological and hemodynamic characteristics of the ophthalmic artery (OA) in patients with white matter hyperintensity (WMH), and the association of the presence and severity of WMH with OA characteristics. Methods: This cross-sectional study included 44 eyes of 25 patients with WMH and 38 eyes of 19 controls. The Fazekas scale was adopted as criteria for evaluating the severity of white matter hyperintensities. The morphological characteristics of the OA were measured on the basis of three-dimensional reconstruction. The hemodynamic parameters of the OA were calculated using computational fluid dynamics simulations. Results: Compared with the control group, the diameter (16.0±0.27 mm vs. 1.71±0.18 mm, P=0.029), median blood flow velocity (0.12 m/s vs. 0.22 m/s, P<0.001), mass flow ratio (2.16% vs. 3.94%, P=0.012) and wall shear stress (2.65 Pa vs. 9.31 Pa, P<0.001) of the OA in patients with WMH were significantly decreased. After adjusting for confounding factors, the diameter, blood flow velocity, wall shear stress, and mass flow ratio of the OA were significantly associated with the presence of WMH. Male sex and high low-density protein level were associated with moderate-to-severe total WMH, and smoking was associated with the moderate-to-severe periventricular WMH. Conclusions: The diameter, blood flow velocity, mass flow ratio, and wall shear stress of the OA were independently associated with the presence of WMH. Atherosclerosis might be involved in the common mechanism of the occurrence of WMH and the OA changes.


Asunto(s)
Hemodinámica , Arteria Oftálmica , Sustancia Blanca , Humanos , Masculino , Femenino , Arteria Oftálmica/diagnóstico por imagen , Arteria Oftálmica/fisiopatología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiopatología , Sustancia Blanca/irrigación sanguínea , Sustancia Blanca/patología , Estudios Transversales , Hemodinámica/fisiología , Persona de Mediana Edad , Anciano , Velocidad del Flujo Sanguíneo , Imagen por Resonancia Magnética , Adulto
18.
Shanghai Kou Qiang Yi Xue ; 33(2): 180-185, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-39005096

RESUMEN

PURPOSE: To investigate the efficacy of a modified maxillary protraction appliance in patients of skeletal Class Ⅲ with crowding. METHODS: Forty patients with skeletal Class Ⅲ malocclusion were divided into two groups, with 20 patients in each group. The experimental group had molar in a neutral or distal relationship and applied a modified maxillary protraction appliance, while the control group had molar mesial relationship and applied a conventional maxillary protraction appliance. Lateral cephalometric radiographs were taken before and after treatment in both groups for comparison. SPSS 22.0 software package was used for data analysis. RESULTS: The angle measurements taken before and after treatment showed a significant increase in SNA, ANB, SN-MP and U4-SN(P<0.01), while SNB decreased(P<0.01) in both groups. SN-OL changes were statistically different before and after treatment in the experimental group(P<0.05). The sagittal measurements before and after treatment in both groups showed significant alterations in all(P<0.05) but the length of the maxillary arch in both groups. For vertical measurements, U1-PP, L1-MP, U4-SN, U6-SN, and ANS-ME all increased (P<0.05), while the changes of U4-PP and U6-PP in the two groups before and after treatment were statistically different(P<0.05). Compared with the control group, the experimental group had a significantly increased maxillary arch length, a more remote location at U6, and a less variable molar relationship after treatment(P<0.01). The two groups showed a variable amount of cephalometric measurements before and after treatment: the experimental group had a significant increase in maxillary arch length, a more remote position at U6, and a smaller change in molar relationship compared to the control group(P<0.01). CONCLUSIONS: The modified maxillary protraction appliance showed good results for maxillary protraction and pushing the molar distally in patients with skeletal Class Ⅲ with crowding at neutral or distal molar relationship.


Asunto(s)
Cefalometría , Maloclusión de Angle Clase III , Maxilar , Humanos , Maloclusión de Angle Clase III/terapia , Maloclusión/terapia
19.
Ecotoxicol Environ Saf ; 283: 116811, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39083873

RESUMEN

In this work, the relationship and kinetics of biodegradation and bio-adsorption of benzo[a]pyrene (BaP) by Bacillus and Ascomycota were explored, and the metabolites of BaP under mixed microbial coculture were analyzed and characterized. The results show that BaP was removed through both biosorption and biodegradation. Under mixed microbial coculture, biosorption played a significant role in the early stage and biodegradation was predominant in the later stage. During the removal of BaP, the fungi exhibited remarkable adsorption capabilities for BaP with an adsorption efficiency (AE) of 38.14 %, while bacteria had a best degradation for BaP with a degradation efficiency (DE) of 56.13 %. Under the mixed microbial culture, the removal efficiency (RE) of BaP by the synergistic action of fungi and bacteria reached up to 76.12 % within 15 days. Kinetics analysis illustrated that the degradation and adsorption process of BaP were well fit to the first-order and the pseudo-second-order kinetic models, respectively. The research on the relationship between degradation and adsorption during microbial removal of BaP, as well as the synergistic effects of fungi and bacteria, will provide a theoretical guidance for two or even synthetic microbial communities.

20.
J Agric Food Chem ; 72(31): 17649-17657, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39047266

RESUMEN

Oxathiapiprolin (OXA), which targets the oxysterol-binding protein (OSBP), is an outstanding piperidinyl thiazole isoxazoline (PTI) fungicide that can be used to control oomycetes diseases. In this study, starting from the structure of OXA, a series of novel OSBP inhibitors were designed and synthesized by introducing an indole moiety to replace the pyrazole in OXA. Finally, compound b24 was found to exhibit the highest control effect (82%) against cucumber downy mildew (CDM) in the greenhouse at a very low dosage of 0.069 mg/L, which was comparable to that of OXA (88%). Furthermore, it showed better activity against potato late blight (PLB) than other derivatives of indole. The computational results showed that the R-conformation of b24 should be the dominant conformation binding to PcOSBP. The results of the present work indicate that the 3-fluorine-indole ring is a favorable fragment to increasing the electronic energy when binding with PcOSBP. Furthermore, compound b24 could be used as a lead compound for the discovery of new OSBP inhibitors.


Asunto(s)
Fungicidas Industriales , Enfermedades de las Plantas , Fungicidas Industriales/química , Fungicidas Industriales/farmacología , Enfermedades de las Plantas/microbiología , Relación Estructura-Actividad , Indoles/química , Indoles/farmacología , Cucumis sativus/química , Cucumis sativus/microbiología , Oomicetos/efectos de los fármacos , Solanum tuberosum/química , Estructura Molecular , Simulación del Acoplamiento Molecular , Descubrimiento de Drogas , Hidrocarburos Fluorados , Pirazoles
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