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1.
Nature ; 627(8004): 680-687, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38448587

RESUMO

Methods for selective covalent modification of amino acids on proteins can enable a diverse array of applications, spanning probes and modulators of protein function to proteomics1-3. Owing to their high nucleophilicity, cysteine and lysine residues are the most common points of attachment for protein bioconjugation chemistry through acid-base reactivity3,4. Here we report a redox-based strategy for bioconjugation of tryptophan, the rarest amino acid, using oxaziridine reagents that mimic oxidative cyclization reactions in indole-based alkaloid biosynthetic pathways to achieve highly efficient and specific tryptophan labelling. We establish the broad use of this method, termed tryptophan chemical ligation by cyclization (Trp-CLiC), for selectively appending payloads to tryptophan residues on peptides and proteins with reaction rates that rival traditional click reactions and enabling global profiling of hyper-reactive tryptophan sites across whole proteomes. Notably, these reagents reveal a systematic map of tryptophan residues that participate in cation-π interactions, including functional sites that can regulate protein-mediated phase-separation processes.


Assuntos
Cátions , Ciclização , Indicadores e Reagentes , Proteínas , Triptofano , Cátions/química , Indicadores e Reagentes/química , Oxirredução , Proteoma/química , Triptofano/química , Peptídeos/química , Química Click , Proteínas/química
2.
Nature ; 595(7868): 542-548, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34290429

RESUMO

Rigid molecular sieving materials work well for small molecules with the complete exclusion of large ones1-3, and molecules with matching physiochemical properties may be separated using dynamic molecular sieving materials4-6. Metal-organic frameworks (MOFs)7-9 are known for their precise control of structures and functions on a molecular level10-15. However, the rational design of local flexibility in the MOF framework for dynamic molecular sieving remains difficult and challenging. Here we report a MOF material (JNU-3a) featuring one-dimension channels with embedded molecular pockets opening to propylene (C3H6) and propane (C3H8) at substantially different pressures. The dynamic nature of the pockets is revealed by single-crystal-to-single-crystal transformation upon exposure of JNU-3a to an atmosphere of C3H6 or C3H8. Breakthrough experiments demonstrate that JNU-3a can realize high-purity C3H6 (≥99.5%) in a single adsorption-desorption cycle from an equimolar C3H6/C3H8 mixture over a broad range of flow rates, with a maximum C3H6 productivity of 53.5 litres per kilogram. The underlying separation mechanism-orthogonal-array dynamic molecular sieving-enables both large separation capacity and fast adsorption-desorption kinetics. This work presents a next-generation sieving material design that has potential for applications in adsorptive separation.

3.
Proc Natl Acad Sci U S A ; 120(27): e2304306120, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37364127

RESUMO

Understanding the fundamental interaction of nanoparticles at plant interfaces is critical for reaching field-scale applications of nanotechnology-enabled plant agriculture, as the processes between nanoparticles and root interfaces such as root compartments and root exudates remain largely unclear. Here, using iron deficiency-induced plant chlorosis as an indicator phenotype, we evaluated the iron transport capacity of Fe3O4 nanoparticles coated with citrate (CA) or polyacrylic acid (PAA) in the plant rhizosphere. Both nanoparticles can be used as a regulator of plant hormones to promote root elongation, but they regulate iron deficiency in plant in distinctive ways. In acidic root exudates secreted by iron-deficient Arabidopsis thaliana, CA-coated particles released fivefold more soluble iron by binding to acidic exudates mainly through hydrogen bonds and van der Waals forces and thus, prevented iron chlorosis more effectively than PAA-coated particles. We demonstrate through roots of mutants and visualization of pH changes that acidification of root exudates primarily originates from root tips and the synergistic mode of nanoparticle uptake and transformation in different root compartments. The nanoparticles entered the roots mainly through the epidermis but were not affected by lateral roots or root hairs. Our results show that magnetic nanoparticles can be a sustainable source of iron for preventing leaf chlorosis and that nanoparticle surface coating regulates this process in distinctive ways. This information also serves as an urgently needed theoretical basis for guiding the application of nanomaterials in agriculture.


Assuntos
Anemia Hipocrômica , Arabidopsis , Deficiências de Ferro , Nanopartículas de Magnetita , Ferro/metabolismo , Transporte Biológico , Anemia Hipocrômica/metabolismo , Arabidopsis/metabolismo , Raízes de Plantas/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(22): e2220148120, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37216506

RESUMO

Exploring the potential lead compounds for Alzheimer's disease (AD) remains one of the challenging tasks. Here, we report that the plant extract conophylline (CNP) impeded amyloidogenesis by preferentially inhibiting BACE1 translation via the 5' untranslated region (5'UTR) and rescued cognitive decline in an animal model of APP/PS1 mice. ADP-ribosylation factor-like protein 6-interacting protein 1 (ARL6IP1) was then found to mediate the effect of CNP on BACE1 translation, amyloidogenesis, glial activation, and cognitive function. Through analysis of the 5'UTR-targetd RNA-binding proteins by RNA pulldown combined with LC-MS/MS, we found that FMR1 autosomal homolog 1 (FXR1) interacted with ARL6IP1 and mediated CNP-induced reduction of BACE1 by regulating the 5'UTR activity. Without altering the protein levels of ARL6IP1 and FXR1, CNP treatment promoted ARL6IP1 interaction with FXR1 and inhibited FXR1 binding to the 5'UTR both in vitro and in vivo. Collectively, CNP exhibited a therapeutic potential for AD via ARL6IP1. Through pharmacological manipulation, we uncovered a dynamic interaction between FXR1 and the 5'UTR in translational control of BACE1, adding to the understanding of the pathophysiology of AD.


Assuntos
Doença de Alzheimer , Animais , Camundongos , Regiões 5' não Traduzidas , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Cromatografia Líquida , Proteína do X Frágil da Deficiência Intelectual/genética , Biossíntese de Proteínas , Espectrometria de Massas em Tandem
5.
Traffic ; 24(1): 20-33, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36412210

RESUMO

AP2S1 is the sigma 2 subunit of adaptor protein 2 (AP2) that is essential for endocytosis. In this study, we investigated the potential role of AP2S1 in intracellular processing of amyloid precursor protein (APP), which contributes to the pathogenesis of Alzheimer disease (AD) by generating the toxic ß-amyloid peptide (Aß). We found that knockdown or overexpression of AP2S1 decreased or increased the protein levels of APP and Aß in cells stably expressing human full-length APP695, respectively. This effect was unrelated to endocytosis but involved lysosomal degradation. Morphological studies revealed that silencing of AP2S1 promoted the translocalization of APP from RAB9-positive late endosomes (LE) to LAMP1-positive lysosomes, which was paralleled by the enhanced LE-lysosome fusion. In support, silencing of vacuolar protein sorting-associated protein 41 (VPS41) that is implicated in LE-lyso fusion prevented AP2S1-mediated regulation of APP degradation and translocalization. In APP/PS1 mice, an animal model of AD, AAV-mediated delivery of AP2S1 shRNA in the hippocampus significantly reduced the protein levels of APP and Aß, with the concomitant APP translocalization, LE-lyso fusion and the improved cognitive functions. Taken together, these data uncover a LE-lyso fusion mechanism in APP degradation and suggest a novel role for AP2S1 in the pathophysiology of AD.


Assuntos
Subunidades sigma do Complexo de Proteínas Adaptadoras , Doença de Alzheimer , Camundongos , Humanos , Animais , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/metabolismo , Endossomos/metabolismo , Lisossomos/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Complexo 2 de Proteínas Adaptadoras/metabolismo , Subunidades sigma do Complexo de Proteínas Adaptadoras/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
6.
FASEB J ; 38(15): e23864, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39109513

RESUMO

Little is known about the blood-feeding physiology of arbovirus vector Aedes aegypti although this type of mosquito is known to transmit infectious diseases dengue, Zika, yellow fever, and chikungunya. Blood feeding in the female A. aegypti mosquito is essential for egg maturation and for transmission of disease agents between human subjects. Here, we identify the A. aegypti sulfakinin receptor gene SKR from the A. aegypti genome and show that SKR is expressed at different developmental stages and in varied anatomical localizations in the adult mosquito (at three days after eclosion), with particularly high expression in the CNS. Knockingdown sulfakinin and sulfakinin receptor gene expression in the female A. aegypti results in increased blood meal intake, but microinjection in the thorax of the sulfakinin peptide 1 and 2 both inhibits dose dependently blood meal intake (and delays the time course of blood intake), which is reversible with receptor antagonist. Sulfakinin receptor expressed ectopically in mammalian cells CHO-K1 responds to sulfakinin stimulation with persistent calcium spikes, blockable with receptor antagonist. These data together suggest that activation of the Gq protein-coupled (i.e., calcium-mobilizing) sulfakinin receptor inhibits blood meal intake in female A. aegypti mosquitoes and could serve as a strategic node for the future control of A. aegypti mosquito reproduction/population and disease transmission.


Assuntos
Aedes , Receptores Acoplados a Proteínas G , Animais , Aedes/metabolismo , Aedes/genética , Feminino , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Células CHO , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Cricetulus , Comportamento Alimentar/fisiologia , Mosquitos Vetores
7.
J Cell Mol Med ; 28(3): e18114, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38323741

RESUMO

Patients with Philadelphia chromosome-like acute lymphoblastic leukaemia (Ph-like ALL) often face a grim prognosis, with PDGFRB gene fusions being commonly detected in this subgroup. Our study has unveiled a newfound fusion gene, TERF2::PDGFRB, and we have found that patients carrying this fusion gene exhibit sensitivity to dasatinib. Ba/F3 cells harbouring the TERF2::PDGFRB fusion display IL-3-independent cell proliferation through activation of the p-PDGFRB and p-STAT5 signalling pathways. These cells exhibit reduced apoptosis and demonstrate sensitivity to imatinib in vitro. When transfused into mice, Ba/F3 cells with the TERF2::PDGFRB fusion gene induce tumorigenesis and a shortened lifespan in cell-derived graft models, but this outcome can be improved with imatinib treatment. In summary, we have identified the novel TERF2::PDGFRB fusion gene, which exhibits oncogenic potential both in vitro and in vivo, making it a potential therapeutic target for tyrosine kinase inhibitors (TKIs).


Assuntos
Proteínas de Fusão Oncogênica , Leucemia-Linfoma Linfoblástico de Células Precursoras , Receptor beta de Fator de Crescimento Derivado de Plaquetas , Proteína 2 de Ligação a Repetições Teloméricas , Animais , Humanos , Camundongos , Carcinogênese , Transformação Celular Neoplásica , Mesilato de Imatinib , Inibidores de Proteínas Quinases/farmacologia , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Transdução de Sinais , Fator de Transcrição STAT5/genética , Proteína 2 de Ligação a Repetições Teloméricas/genética , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética
8.
J Am Chem Soc ; 146(13): 8865-8876, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38470125

RESUMO

Formate is a major reactive carbon species in one-carbon metabolism, where it serves as an endogenous precursor for amino acid and nucleic acid biosynthesis and a cellular source of NAD(P)H. On the other hand, aberrant elevations in cellular formate are connected to progression of serious diseases, including cancer and Alzheimer's disease. Traditional methods for formate detection in biological environments often rely on sample destruction or extensive processing, resulting in a loss of spatiotemporal information. To help address these limitations, here we present the design, synthesis, and biological evaluation of a first-generation activity-based sensing system for live-cell formate imaging that relies on iridium-mediated transfer hydrogenation chemistry. Formate facilitates an aldehyde-to-alcohol conversion on various fluorophore scaffolds to enable fluorescence detection of this one-carbon unit, including through a two-color ratiometric response with internal calibration. The resulting two-component probe system can detect changes in formate levels in living cells with a high selectivity over potentially competing biological analytes. Moreover, this activity-based sensing system can visualize changes in endogenous formate fluxes through alterations of one-carbon pathways in cell-based models of human colon cancer, presaging the potential utility of this chemical approach to probe the continuum between one-carbon metabolism and signaling in cancer and other diseases.


Assuntos
NAD , Neoplasias , Humanos , Hidrogenação , NAD/metabolismo , Carbono , Formiatos/química
9.
J Am Chem Soc ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39324803

RESUMO

C3H6 is a crucial building block for many chemicals, yet separating it from other C3 hydrocarbons presents a significant challenge. Herein, we report a hydrolytically stable Cu4I4-triazolate metal-organic framework (MOF) (JNU-9-CH3) featuring 1D channels decorated with readily accessible iodine and nitrogen atoms from Cu4I4 clusters and triazolate linkers, respectively. The exposed iodine and nitrogen atoms allow for cooperative binding of C3 hydrocarbons, as evidenced by in situ single-crystal crystallography and Raman spectroscopy studies. As a result, JNU-9-CH3 exhibits substantially stronger binding affinity for C3H4, CH2═C═CH2, and C3H8 than that for C3H6. Breakthrough experiments confirm its ability to directly separate C3H6 (≥99.99%) from C3H4/CH2═C═CH2/C3H8/C3H6 mixtures at varying ratios and flow rates. Overall, we illustrate the cooperative binding of C3 hydrocarbons in a Cu4I4-triazolate MOF and its highly efficient C3H6 purification from quaternary C3 mixtures. The study highlights the potential of MOF adsorbents with metal-iodide clusters for cooperative bindings and hydrocarbon separations.

10.
Curr Issues Mol Biol ; 46(8): 8710-8725, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39194731

RESUMO

Hollow structures are essential for development and physiological activity. The construction and maintenance of hollow structures never cease throughout the lives of multicellular animals. Epithelial tissue closure is the main strategy used by living organisms to build hollow structures. The high diversity of hollow structures and the simplicity of their development in Drosophila make it an excellent model for the study of hollow structure morphogenesis. In this review, we summarize the tissue closure processes in Drosophila that give rise to or maintain hollow structures and highlight the molecular mechanisms and distinct cell biology involved in these processes.

11.
Radiology ; 311(1): e231461, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38652028

RESUMO

Background Noninvasive tests can be used to screen patients with chronic liver disease for advanced liver fibrosis; however, the use of single tests may not be adequate. Purpose To construct sequential clinical algorithms that include a US deep learning (DL) model and compare their ability to predict advanced liver fibrosis with that of other noninvasive tests. Materials and Methods This retrospective study included adult patients with a history of chronic liver disease or unexplained abnormal liver function test results who underwent B-mode US of the liver between January 2014 and September 2022 at three health care facilities. A US-based DL network (FIB-Net) was trained on US images to predict whether the shear-wave elastography (SWE) value was 8.7 kPa or higher, indicative of advanced fibrosis. In the internal and external test sets, a two-step algorithm (Two-step#1) using the Fibrosis-4 Index (FIB-4) followed by FIB-Net and a three-step algorithm (Three-step#1) using FIB-4 followed by FIB-Net and SWE were used to simulate screening scenarios where liver stiffness measurements were not or were available, respectively. Measures of diagnostic accuracy were calculated using liver biopsy as the reference standard and compared between FIB-4, SWE, FIB-Net, and European Association for the Study of the Liver guidelines (ie, FIB-4 followed by SWE), along with sequential algorithms. Results The training, validation, and test data sets included 3067 (median age, 42 years [IQR, 33-53 years]; 2083 male), 1599 (median age, 41 years [IQR, 33-51 years]; 1124 male), and 1228 (median age, 44 years [IQR, 33-55 years]; 741 male) patients, respectively. FIB-Net obtained a noninferior specificity with a margin of 5% (P < .001) compared with SWE (80% vs 82%). The Two-step#1 algorithm showed higher specificity and positive predictive value (PPV) than FIB-4 (specificity, 79% vs 57%; PPV, 44% vs 32%) while reducing unnecessary referrals by 42%. The Three-step#1 algorithm had higher specificity and PPV compared with European Association for the Study of the Liver guidelines (specificity, 94% vs 88%; PPV, 73% vs 64%) while reducing unnecessary referrals by 35%. Conclusion A sequential algorithm combining FIB-4 and a US DL model showed higher diagnostic accuracy and improved referral management for all-cause advanced liver fibrosis compared with FIB-4 or the DL model alone. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Ghosh in this issue.


Assuntos
Algoritmos , Técnicas de Imagem por Elasticidade , Cirrose Hepática , Humanos , Masculino , Cirrose Hepática/diagnóstico por imagem , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Técnicas de Imagem por Elasticidade/métodos , Adulto , Aprendizado Profundo , Fígado/diagnóstico por imagem , Fígado/patologia , Idoso , Ultrassonografia/métodos
12.
J Org Chem ; 89(7): 4851-4860, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38546258

RESUMO

A Pd-catalyzed one-pot sequential C-H functionalization strategy was utilized to prepare four lycorine alkaloids and one pseudo-lycorine alkaloid from the common intermediate 4. By switching the followed oxidative conditions of air, DMSO/H2O/I2, and DMSO/O2, based on the Pd(PPh3)4/K2CO3/toluene catalytic system, three key intermediates 12a, 12b, and 12c with different substitution patterns could be obtained in a well-controlled manner. As a result, four natural products γ-lycorane, hippadine, anhydrolycorinone, and anhydrolycorine as well as a pseudo-lycorine alkaloid Δ(4a,10b)-6-oxodihydrolycorine were successfully synthesized within 10 steps through this divergent route.

13.
Fish Shellfish Immunol ; 153: 109836, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39147177

RESUMO

Pseudomonas plecoglossicida is one of most important pathogenic bacterial species in large yellow croaker and several other commercially valuable fish species. In our previous study, a GacS deficient mutant (ΔgacS) was constructed and its virulence showed substantially attenuated. In present study, the safety, immunogenicity and protective effect of the ΔgacS were evaluated in large yellow croaker as a live-attenuated vaccine candidate. It was shown that the ΔgacS strain exhibited good safety to large yellow croaker and there was no mortality or clinical symptoms observed in all fish that infected by ΔgacS strain with the doses range from 2 × 105~107 CFU per fish via intraperitoneal injection (IP) or immersion (IM), and almost all bacteria were cleaned up in the spleen of the fish at 14-day post infection. Specific antibodies could be detected at 7-day and 14-day post infection by direct agglutination method, and the valences of antibodies and bactericidal activities of the serum were significant increased with vaccination doses and vaccination time. Moreover, the expressions of some molecules and cytokines involved in specific immune responses were detected in the ΔgacS strain immunization group and control group. After challenged by the wild-type (WT) strain XSDHY-P, the relative percentage survival (RPS) showed highly correlated with the immunized dosage regardless of vaccination methods. It showed that the RPS of the IP groups were 39.47 %, 57.89 %, 71.05 % with the immune dosage in a descending order, respectively, and the RPS of the IM groups were 26.31 %, 36.84 %, 76.31 % with the immune dosage in a descending order, respectively. In summary, the ΔgacS strain exhibited safety and good protective effect to large yellow croaker and was a potential live vaccine candidate.


Assuntos
Doenças dos Peixes , Perciformes , Infecções por Pseudomonas , Pseudomonas , Vacinas Atenuadas , Animais , Doenças dos Peixes/imunologia , Doenças dos Peixes/prevenção & controle , Perciformes/imunologia , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/administração & dosagem , Infecções por Pseudomonas/veterinária , Infecções por Pseudomonas/prevenção & controle , Infecções por Pseudomonas/imunologia , Pseudomonas/imunologia , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas contra Pseudomonas/imunologia , Vacinas contra Pseudomonas/genética , Imunogenicidade da Vacina
14.
BMC Neurol ; 24(1): 59, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336624

RESUMO

OBJECTIVES: Computed tomographic perfusion (CTP) can play an auxiliary role in the selection of patients with acute ischemic stroke for endovascular treatment. However, data on CTP in non-stroke patients with intracranial arterial stenosis are scarce. We aimed to investigate images in patients with asymptomatic intracranial arterial stenosis to determine the detection accuracy and interpretation time of large/medium-artery stenosis or occlusion when combining computed tomographic angiography (CTA) and CTP images. METHODS: We retrospectively reviewed 39 patients with asymptomatic intracranial arterial stenosis from our hospital database from January 2021 to August 2023 who underwent head CTP, head CTA, and digital subtraction angiography (DSA). Head CTA images were generated from the CTP data, and the diagnostic performance for each artery was assessed. Two readers independently interpreted the CTA images before and after CTP, and the results were analyzed. RESULTS: After adding CTP maps, the accuracy (area under the curve) of diagnosing internal carotid artery (R1: 0.847 vs. 0.907, R2: 0.776 vs. 0.887), middle cerebral artery (R1: 0.934 vs. 0.933, R2: 0.927 vs. 0.981), anterior cerebral artery (R1: 0.625 vs. 0.750, R2: 0.609 vs. 0.750), vertebral artery (R1: 0.743 vs. 0.764, R2: 0.748 vs. 0.846), and posterior cerebral artery (R1: 0.390 vs. 0.575, R2: 0.390 vs. 0.585) occlusions increased for both readers (p < 0.05). Mean interpretation time (R1: 72.4 ± 6.1 s vs. 67.7 ± 6.4 s, R2: 77.7 ± 3.8 s vs. 72.6 ± 4.7 s) decreased when using a combination of both images both readers (p < 0.001). CONCLUSIONS: The addition of CTP images improved the accuracy of interpreting CTA images and reduced the interpretation time in asymptomatic intracranial arterial stenosis. These findings support the use of CTP imaging in patients with asymptomatic intracranial arterial stenosis.


Assuntos
AVC Isquêmico , Humanos , Estudos Retrospectivos , Constrição Patológica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Angiografia por Tomografia Computadorizada/métodos , Perfusão , Angiografia Cerebral/métodos
15.
BMC Infect Dis ; 24(1): 361, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549089

RESUMO

BACKGROUND: Pancreaticoduodenectomy (PD) is a complex procedure and easily accompanied by healthcare-associated infections (HAIs). This study aimed to assess the impact of PBD on postoperative infections and clinical outcomes in PD patients. METHODS: The retrospective cohort study were conducted in a tertiary hospital from January 2013 to December 2022. Clinical and epidemiological data were collected from HAIs surveillance system and analyzed. RESULTS: Among 2842 patients who underwent PD, 247 (8.7%) were diagnosed with HAIs, with surgical site infection being the most frequent type (n = 177, 71.7%). A total of 369 pathogenic strains were detected, with Klebsiella pneumoniae having the highest proportion, followed by Enterococcu and Escherichia coli. Although no significant association were observed generally between PBD and postoperative HAIs, subgroup analysis revealed that PBD was associated with postoperative HAIs in patients undergoing robotic PD (aRR = 2.174; 95% CI:1.011-4.674; P = 0.047). Prolonging the interval between PBD and PD could reduce postoperative HAIs in patients with cholangiocarcinoma (≥4 week: aRR = 0.292, 95% CI 0.100-0.853; P = 0.024) and robotic PD (≤2 week: aRR = 3.058, 95% CI 1.178-7.940; P = 0.022). PBD was also found to increase transfer of patients to ICU (aRR = 1.351; 95% CI 1.119-1.632; P = 0.002), extended length of stay (P < 0.001) and postoperative length of stay (P = 0.004). CONCLUSION: PBD does not exhibit a significant association with postoperative HAIs or other outcomes. However, the implementation of robotic PD, along with a suitable extension of the interval between PBD and PD, appear to confer advantages concerning patients' physiological recuperation. These observations suggest potential strategies that may contribute to enhanced patient outcomes.


Assuntos
Infecção Hospitalar , Pancreaticoduodenectomia , Humanos , Estudos Retrospectivos , Pancreaticoduodenectomia/efeitos adversos , Pancreaticoduodenectomia/métodos , Cuidados Pré-Operatórios/métodos , Drenagem/métodos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/etiologia , Atenção à Saúde , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento
16.
Phys Chem Chem Phys ; 26(4): 3285-3295, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38197170

RESUMO

In two-dimensional (2D) materials, breaking the inversion symmetry plays an important role in valleytronics. Ferrovalley (FV) materials can achieve spontaneous valley polarization (VP) without additional modulation due to the magnetic exchange interaction and strong spin-orbit coupling. Using first-principles calculations, we predict a new 2D material, Janus FeClSH, which exhibits a large spontaneous VP. This monolayer is a perfect FV material, where the valence band maximum and conduction band minimum are located at the K/K' point. A large VP of 102.95 meV is spontaneously generated for the case of out-of-plane magnetization. Additionally, we propose that the irradiating circularly polarized light can be used to realize VP for the case of in-plane magnetization. Remarkably, a triangular nanoflake of FeClSH with armchair edges can show nontrivial corner states, exhibiting a second-order topological insulator (SOTI) state. The VP effect and SOTI state are tunable with the Hubbard U parameter, making the FeClSH monolayer promising for the study of the coupling between VP and SOTI.

17.
J Phys Chem A ; 128(40): 8803-8815, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39344670

RESUMO

Single-walled carbon nanotubes (SWCNTs) have gained a lot of attention in the past few decades due to their promising optoelectronic properties. In addition, SWCNTs can form complexes that have good chemical stability and transport properties with other optical functional materials through noncovalent interactions. Elucidating the detailed mechanism of these complexes is of great significance for improving their optoelectronic properties. Nevertheless, simulating the photoinduced dynamics of these complexes accurately is rather challenging since they usually contain hundreds of atoms. To save computational efforts, most of the previous works have ignored the excitonic effects by employing nonadiabatic carrier (electron and hole) dynamics simulations. To properly consider the influence of excitonic effects on the photoinduced ultrafast processes of the SWCNT-tetraphenyl porphyrin (H2TPP) complex and to further improve the computational efficiency, we developed the nonadiabatic molecular dynamics (NAMD) method based on the extended tight binding-based simplified Tamm-Dancoff approximation (sTDA-xTB), which is applied to study the ultrafast photoinduced dynamics of the noncovalent SWCNT-porphyrin complex. In combination with statically electronic structure calculations, the present work successfully reveals the detailed microscopic mechanism of the ultrafast excitation energy transfer process of the complex. Upon local excitation on the H2TPP molecule, an ultrafast energy transfer process occurs from H2TPP (SWCNT-H2TPP*) to SWCNT (SWCNT*-H2TPP) within 10 fs. Then, two slower processes corresponding to the energy transfer from H2TPP to SWCNT and hole transfer from H2TPP to SWCNT take place in the 1 ps time scale. The sTDA-xTB-based electronic structure calculation and NAMD simulation results not only match the previous experimental observations from static and transient spectra but also provide more insights into the detailed information on the complex's photoinduced dynamics. Therefore, the sTDA-xTB-based NAMD method is a powerful theoretical tool for studying the ultrafast photoinduced dynamics in large extended systems with a large number of electronically excited states, which could be helpful for the subsequent design of SWCNT-based functional materials.

18.
Acta Pharmacol Sin ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060522

RESUMO

Delta like non-canonical Notch ligand 1 (DLK1), as a member of epidermal growth factor-like family, plays a critical role in somatic growth, tissue development and possibly tissue renewal. Though previous studies had indicated that DLK1 contributed to adipogenesis and myogenesis, it's still controversial whether DLK1 affects angiogenesis and how it interacts with Notch signaling with numerous conflicting reports from different models. Based on our preliminary finding that DLK1 expression was up-regulated in mice ischemic gastrocnemius and in the border zone of infarcted myocardium, we administered either recombinant DLK1 (rDLK1) or PBS in C57BL/6 mice after establishment of hindlimb ischemia (HLI) and myocardial infarction (MI), respectively. Exogenous rDLK1 administration significantly improved both blood perfusion of mice ischemic hindlimbs and muscle motor function on the 3rd, 7th day after HLI, by promoting neovascularization. Similar effect on neovascularization was verified in mice on the 28th day after MI as well as improvement of cardiac failure. Correspondingly, the number of CD34+KDR+ cells, indicated as endothelial progenitor cells (EPCs), was significantly in mice ischemic gastrocnemius by rDLK1 administration, which was abrogated by DAPT as the specific inhibitor of Notch intracellular domain (NICD). Furthermore, bone marrow mononuclear cells were obtained from C57BL/6 mice and differentiated to EPCs ex vivo. Incubation with rDLK1 triggered Notch1 mRNA and NICD protein expressions in EPCs as exposed to hypoxia and serum deprivation, promoting EPCs proliferation, migration, anti-apoptosis and tube formation. Otherwise, rDLK1 incubation significantly decreased intracellular and mitochondrial reactive oxygen species, increased ATP content and mitochondrial membrane potential, downregulated short isoform of OPA-1 expression whereas upregulated mitofusin (-1, -2) expression in EPCs by Notch1 signaling, which were all abrogated by DAPT. In summary, the present study unveils the pro-angiogenesis and its mechanism of rDLK1 through activation of Notch1 signaling in endothelial progenitor cells.

19.
BMC Med Imaging ; 24(1): 242, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285357

RESUMO

OBJECTIVES: To establish a nomogram for differentiating malignant and benign focal liver lesions (FLLs) using ultrasomics features derived from contrast-enhanced ultrasound (CEUS). METHODS: 527 patients were retrospectively enrolled. On the training cohort, ultrasomics features were extracted from CEUS and b-mode ultrasound (BUS). Automatic feature selection and model development were performed using the Ultrasomics-Platform software, outputting the corresponding ultrasomics scores. A nomogram based on the ultrasomics scores from artery phase (AP), portal venous phase (PVP) and delayed phase (DP) of CEUS, and clinical factors were established. On the validation cohort, the diagnostic performance of the nomogram was assessed and compared with seniorexpert and resident radiologists. RESULTS: In the training cohort, the AP, PVP and DP scores exhibited better differential performance than BUS score, with area under the curve (AUC) of 84.1-85.1% compared with the BUS (74.6%, P < 0.05). In the validation cohort, the AUC of combined nomogram and expert was significantly higher than that of the resident (91.4% vs. 89.5% vs. 79.3%, P < 0.05). The combined nomogram had a comparable sensitivity with the expert and resident (95.2% vs. 98.4% vs. 97.6%), while the expert had a higher specificity than the nomogram and the resident (80.6% vs. 72.2% vs. 61.1%, P = 0.205). CONCLUSIONS: A CEUS ultrasomics based nomogram had an expert level performance in FLL characterization.


Assuntos
Meios de Contraste , Neoplasias Hepáticas , Nomogramas , Ultrassonografia , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Ultrassonografia/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Estudos Retrospectivos , Diagnóstico Diferencial , Adulto , Idoso , Sensibilidade e Especificidade , Fígado/diagnóstico por imagem
20.
Curr Microbiol ; 81(11): 396, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375231

RESUMO

Strain DM2021935T representing a novel Acinetobacter species was isolated from a spoiled bath lotion in Guangdong, China. Based on 16S rRNA gene phylogenetic analysis, strain DM2021935T was closely related to 'Acinetobacter thutiue' VNH17T, Acinetobacter junii CIP 64.5 T, and Acinetobacter tibetensis Y-23 T. Cells of strain DM2021935T were Gram-stain-negative, non-spore-forming, strictly aerobic, catalase-positive, oxidase-negative, α-hemolytic, and non-motile. Strain DM2021935T exhibited growth in 1-3% (w/v) NaCl at temperatures ranging from 4 to 37 °C and tolerated pH levels from 6.0 to 8.0. The predominant fatty acids in strain DM2021935T are C12:0, C16:0, C18:1 ω9c, and summed feature 3. Polar lipid profiles included glycolipids, phospholipids, phosphatidylethanolamine, and phosphatidyl-N-methylethanolamine. The identified respiratory quinones were ubiquinone Q-8 and Q-9. The genomic size of DM2021935T comprised 4.15 Mb, consisting of one chromosome (3,827,633 bp) and two plasmids (241,357 and 83,010 bp). The G + C content was 41.8%. The average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values between strain DM2021935T and phylogenetically related type strains were below the species delineation thresholds (72.2-95.4, 53.1-87.0, and 20.4-66.4%, respectively). AntiSMASH analysis identified four gene clusters: non-ribosomal peptide synthetase, non-alpha poly-amino group acids, YcaO cyclodehydratase, and aryl polyene biosynthesis. Based on genotypic data, strain DM2021935T represents a novel species within the genus Acinetobacter. The proposed name for the novel species is Acinetobacter corruptisaponis sp. nov. (type strain DM2021935T = KCTC 92772 T = GDMCC 1.3703 T).


Assuntos
Acinetobacter , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Filogenia , RNA Ribossômico 16S , Acinetobacter/genética , Acinetobacter/classificação , Acinetobacter/isolamento & purificação , RNA Ribossômico 16S/genética , Ácidos Graxos/química , DNA Bacteriano/genética , China , Genoma Bacteriano , Análise de Sequência de DNA , Fosfolipídeos/análise
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