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1.
BMC Microbiol ; 24(1): 241, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961344

RESUMEN

BACKGROUND: Staphylococcus aureus, a commensal bacterium, colonizes the skin and mucous membranes of approximately 30% of the human population. Apart from conventional resistance mechanisms, one of the pathogenic features of S. aureus is its ability to survive in a biofilm state on both biotic and abiotic surfaces. Due to this characteristic, S. aureus is a major cause of human infections, with Methicillin-Resistant Staphylococcus aureus (MRSA) being a significant contributor to both community-acquired and hospital-acquired infections. RESULTS: Analyzing non-repetitive clinical isolates of MRSA collected from seven provinces and cities in China between 2014 and 2020, it was observed that 53.2% of the MRSA isolates exhibited varying degrees of ability to produce biofilm. The biofilm positivity rate was notably high in MRSA isolates from Guangdong, Jiangxi, and Hubei. The predominant MRSA strains collected in this study were of sequence types ST59, ST5, and ST239, with the biofilm-producing capability mainly distributed among moderate and weak biofilm producers within these ST types. Notably, certain sequence types, such as ST88, exhibited a high prevalence of strong biofilm-producing strains. The study found that SCCmec IV was the predominant type among biofilm-positive MRSA, followed by SCCmec II. Comparing strains with weak and strong biofilm production capabilities, the positive rates of the sdrD and sdrE were higher in strong biofilm producers. The genetic determinants ebp, icaA, icaB, icaC, icaD, icaR, and sdrE were associated with strong biofilm production in MRSA. Additionally, biofilm-negative MRSA isolates showed higher sensitivity rates to cefalotin (94.8%), daptomycin (94.5%), mupirocin (86.5%), teicoplanin (94.5%), fusidic acid (81.0%), and dalbavancin (94.5%) compared to biofilm-positive MRSA isolates. The biofilm positivity rate was consistently above 50% in all collected specimen types. CONCLUSIONS: MRSA strains with biofilm production capability warrant increased vigilance.


Asunto(s)
Biopelículas , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/fisiología , China/epidemiología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Antibacterianos/farmacología , Genes Bacterianos/genética , Humanos
2.
Eur Radiol ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38834786

RESUMEN

OBJECTIVES: We aimed to develop and validate a radiomics nomogram based on dual-energy computed tomography (DECT) images and clinical features to classify the time since stroke (TSS), which could facilitate stroke decision-making. MATERIALS AND METHODS: This retrospective three-center study consecutively included 488 stroke patients who underwent DECT between August 2016 and August 2022. The eligible patients were divided into training, test, and validation cohorts according to the center. The patients were classified into two groups based on an estimated TSS threshold of ≤ 4.5 h. Virtual images optimized the visibility of early ischemic lesions with more CT attenuation. A total of 535 radiomics features were extracted from polyenergetic, iodine concentration, virtual monoenergetic, and non-contrast images reconstructed using DECT. Demographic factors were assessed to build a clinical model. A radiomics nomogram was a tool that the Rad score and clinical factors to classify the TSS using multivariate logistic regression analysis. Predictive performance was evaluated using receiver operating characteristic (ROC) analysis, and decision curve analysis (DCA) was used to compare the clinical utility and benefits of different models. RESULTS: Twelve features were used to build the radiomics model. The nomogram incorporating both clinical and radiomics features showed favorable predictive value for TSS. In the validation cohort, the nomogram showed a higher AUC than the radiomics-only and clinical-only models (AUC: 0.936 vs 0.905 vs 0.824). DCA demonstrated the clinical utility of the radiomics nomogram model. CONCLUSIONS: The DECT-based radiomics nomogram provides a promising approach to predicting the TSS of patients. CLINICAL RELEVANCE STATEMENT: The findings support the potential clinical use of DECT-based radiomics nomograms for predicting the TSS. KEY POINTS: Accurately determining the TSS onset is crucial in deciding a treatment approach. The radiomics-clinical nomogram showed the best performance for predicting the TSS. Using the developed model to identify patients at different times since stroke can facilitate individualized management.

3.
Eur Radiol ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856782

RESUMEN

OBJECTIVES: Aneurysm wall enhancement (AWE) on high-resolution contrast-enhanced vessel wall MRI (VWMRI) is an emerging biomarker for intracranial aneurysms (IAs) stability. Quantification methods of AWE in the literature, however, are variable. We aimed to determine the optimal post-contrast timing to quantify AWE in both saccular and fusiform IAs. MATERIALS AND METHODS: Consecutive patients with unruptured IAs were prospectively recruited. VWMRI was acquired on 1 pre-contrast and 4 consecutive post-contrast phases (each phase was 9 min). Signal intensity values of cerebrospinal fluid (CSF) and aneurysm wall on pre- and 4 post-contrast phases were measured to determine the aneurysm wall enhancement index (WEI). AWE was also qualitatively analyzed on post-contrast images using previous grading criteria. The dynamic changes of AWE grade and WEI were analyzed for both saccular and fusiform IAs. RESULTS: Thirty-four patients with 42 IAs (27 saccular IAs and 15 fusiform IAs) were included. The changes in AWE grade occurred in 8 (30%) saccular IAs and 6 (40%) in fusiform IAs during the 4 post-contrast phases. The WEI of fusiform IAs decreased 22.0% over time after contrast enhancement (p = 0.009), while the WEI of saccular IAs kept constant during the 4 post-contrast phases (p > 0.05). CONCLUSIONS: When performing quantitative analysis of AWE, acquiring post-contrast VWMRI immediately after contrast injection achieves the strongest AWE for fusiform IAs. While the AWE degree is stable for 36 min after contrast injection for saccular IAs. CLINICAL RELEVANCE STATEMENT: The standardization of imaging protocols and analysis methods for AWE will be helpful for imaging surveillance and further treatment decisions of patients with unruptured IAs. KEY POINTS: Imaging protocols and measurements of intracranial aneurysm wall enhancement are reported heterogeneously. Aneurysm wall enhancement for fusiform intracranial aneurysms (IAs) is strongest immediately post-contrast, and stable for 36 min for saccular IAs. Future multi-center studies should investigate aneurysm wall enhancement as an emerging marker of aneurysm growth and rupture.

4.
Nat Prod Res ; : 1-7, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38752831

RESUMEN

Polysaccharides and flavonoids have excellent antioxidant properties and tyrosinase inhibitory effects. In this paper, the antioxidant capacity of Inonotus sanghuang extract and its inhibition kinetics on mushroom tyrosinase were investigated to determine the preparation process of Inonotus sanghuang primary whitening gel. By conducting experimental studies on the effects of water extract and alcohol extract of Inonotus sanghuang on antioxidant capacity and tyrosinase activity, their inhibitory ability and types of inhibitory effects were determined. The single factor experiment was used to determine the preparation process of Sanghuang primary whitening gel. This study has proven that the extract of Inonotus sanghuang possesses antioxidant and tyrosinase inhibitory capabilities. It also identified the preparation process for the primary whitening gel of Inonotus sanghuang, thereby providing a theoretical and experimental basis for the development of whitening products utilising Inonotus sanghuang.

5.
Adv Mater ; : e2400261, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38741451

RESUMEN

Intracranial implants for diagnosis and treatment of brain diseases have been developed over the past few decades. However, the platform of conventional implantable devices still relies on invasive probes and bulky sensors in conjunction with large-area craniotomy and provides only limited biometric information. Here, an implantable multi-modal sensor array that can be injected through a small hole in the skull and inherently spread out for conformal contact with the cortical surface is reported. The injectable sensor array, composed of graphene multi-channel electrodes for neural recording and electrical stimulation and MoS2-based sensors for monitoring intracranial temperature and pressure, is designed based on a mesh structure whose elastic restoring force enables the contracted device to spread out. It is demonstrated that the sensor array injected into a rabbit's head can detect epileptic discharges on the surface of the cortex and mitigate it by electrical stimulation while monitoring both intracranial temperature and pressure. This method provides good potential for implanting a variety of functional devices via minimally invasive surgery.

6.
Helicobacter ; 29(2): e13066, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38468575

RESUMEN

BACKGROUND: SHP1 has been documented as a tumor suppressor and it was thought to play an antagonistic role in the pathogenesis of Helicobacter pylori infection. In this study, the exact mechanism of this antagonistic action was studied. MATERIALS AND METHODS: AGS, MGC803, and GES-1 cells were infected with H. pylori, intracellular distribution changes of SHP1 were first detected by immunofluorescence. SHP1 overexpression and knockdown were then constructed in these cells to investigate its antagonistic roles in H. pylori infection. Migration and invasion of infected cells were detected by transwell assay, secretion of IL-8 was examined via ELISA, the cells with hummingbird-like alteration were determined by microexamination, and activation of JAK2/STAT3, PI3K/Akt, and ERK pathways were detected by immunoblotting. Mice infection model was established and gastric pathological changes were evaluated. Finally, the SHP1 activator sorafenib was used to analyze the attenuating effect of SHP1 activation on H. pylori pathogenesis in vitro and in vivo. RESULTS: The sub-localization of SHP1 changed after H. pylori infection, specifically that the majority of the cytoplasmic SHP1 was transferred to the cell membrane. SHP1 inhibited H. pylori-induced activation of JAK2/STAT3 pathway, PI3K/Akt pathway, nuclear translocation of NF-κB, and then reduced EMT, migration, invasion, and IL-8 secretion. In addition, SHP1 inhibited the formation of CagA-SHP2 complex by dephosphorylating phosphorylated CagA, reduced ERK phosphorylation and the formation of CagA-dependent hummingbird-like cells. In the mice infection model, gastric pathological changes were observed and increased IL-8 secretion, indicators of cell proliferation and EMT progression were also detected. By activating SHP1 with sorafenib, a significant curative effect against H. pylori infection was obtained in vitro and in vivo. CONCLUSIONS: SHP1 plays an antagonistic role in H. pylori pathogenesis by inhibiting JAK2/STAT3 and PI3K/Akt pathways, NF-κB nuclear translocation, and CagA phosphorylation, thereby reducing cell EMT, migration, invasion, IL-8 secretion, and hummingbird-like changes.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Animales , Ratones , Proteínas Bacterianas/metabolismo , Antígenos Bacterianos/metabolismo , Helicobacter pylori/fisiología , FN-kappa B/metabolismo , Interleucina-8/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Infecciones por Helicobacter/patología , Sorafenib/metabolismo , Células Epiteliales/metabolismo
7.
Int J Antimicrob Agents ; 63(5): 107160, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38537721

RESUMEN

In a vast majority of bacteria, protozoa and plants, the methylerythritol phosphate (MEP) pathway is utilized for the synthesis of isopentenyl diphosphate (IDP) and dimethylallyl diphosphate (DMADP), which are precursors for isoprenoids. Isoprenoids, such as cholesterol and coenzyme Q, play a variety of crucial roles in physiological activities, including cell-membrane formation, protein degradation, cell apoptosis, and transcription regulation. In contrast, humans employ the mevalonate (MVA) pathway for the production of IDP and DMADP, rendering proteins in the MEP pathway appealing targets for antimicrobial agents. This pathway consists of seven consecutive enzymatic reactions, of which 4-diphosphocytidyl-2C-methyl-D-erythritol synthase (IspD) and 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase (IspF) catalyze the third and fifth steps, respectively. In this study, we characterized the enzymatic activities and protein structures of Helicobacter pylori IspDF and Acinetobacter baumannii IspD. Then, using the direct interaction-based thermal shift assay, we conducted a compound screening of an approved drug library and identified 27 hit compounds potentially binding to AbIspD. Among them, two natural products, rosmarinic acid and tanshinone IIA sodium sulfonate, exhibited inhibitory activities against HpIspDF and AbIspD, by competing with one of the substrates, MEP. Moreover, tanshinone IIA sodium sulfonate also demonstrated certain antibacterial effects against H. pylori. In summary, we identified two IspD inhibitors from approved ingredients, broadening the scope for antibiotic discovery targeting the MEP pathway.


Asunto(s)
Acinetobacter baumannii , Antibacterianos , Helicobacter pylori , Hemiterpenos , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/enzimología , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/enzimología , Antibacterianos/farmacología , Inhibidores Enzimáticos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Productos Biológicos/farmacología , Productos Biológicos/química , Compuestos Organofosforados/farmacología , Humanos , Transferasas (Grupos de Otros Fosfatos Sustitutos)/antagonistas & inhibidores , Transferasas (Grupos de Otros Fosfatos Sustitutos)/metabolismo
8.
AJNR Am J Neuroradiol ; 45(3): 262-270, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38388686

RESUMEN

BACKGROUND AND PURPOSE: Intracranial plaque enhancement (IPE) identified by contrast-enhanced vessel wall MR imaging (VW-MR imaging) is an emerging marker of plaque instability related to stroke risk, but there was no standardized timing for postcontrast acquisition. We aim to explore the optimal postcontrast timing by using multiphase contrast-enhanced VW-MR imaging and to test its performance in differentiating culprit and nonculprit lesions. MATERIALS AND METHODS: Patients with acute ischemic stroke due to intracranial plaque were prospectively recruited to undergo VW-MR imaging with 1 precontrast phase and 4 consecutive postcontrast phases (9 minutes and 13 seconds for each phase). The signal intensity (SI) values of the CSF and intracranial plaque were measured on 1 precontrast and 4 postcontrast phases to determine the intracranial plaque enhancement index (PEI). The dynamic changes of the PEI were compared between culprit and nonculprit plaques on the postcontrast acquisitions. RESULTS: Thirty patients with acute stroke (aged 59 ± 10 years, 18 [60%] men) with 113 intracranial plaques were included. The average PEI of all intracranial plaques significantly increased (up to 14%) over the 4 phases. There was significantly increased PEI over the 4 phases for culprit plaques (an average increase of 23%), but this was not observed for nonculprit plaques. For differentiating culprit and nonculprit plaques, we observed that the performance of IPE in the second postcontrast phase (cutoff = 0.83, AUC = 0.829 [0.746-0.893]) exhibited superior accuracy when compared with PEI in the first postcontrast phase (cutoff = 0.48; AUC = 0.768 [0.680-0.843]) (P = .022). CONCLUSIONS: A 9-minute delay of postcontrast acquisition can maximize plaque enhancement and better differentiate between culprit and nonculprit plaques. In addition, culprit and nonculprit plaques have different enhancement temporal patterns, which should be evaluated in future studies.


Asunto(s)
Arteriosclerosis Intracraneal , Accidente Cerebrovascular Isquémico , Placa Aterosclerótica , Accidente Cerebrovascular , Masculino , Humanos , Femenino , Arteriosclerosis Intracraneal/patología , Imagen por Resonancia Magnética/métodos , Placa Aterosclerótica/patología
9.
J Adv Res ; 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38346487

RESUMEN

INTRODUCTION: Despite the high morbidity and mortality, the effective therapies for heart failure with preserved fraction (HFpEF) are limited as the poor understand of its pathophysiological basis. OBJECTIVE: This study was aimed to characterize the cellular heterogeneity and potential mechanisms of HFpEF at single-cell resolution. METHODS: An HFpEF mouse model was induced by a high-fat diet with N-nitro-L-arginine methyl ester. Cells from the hearts were subjected to single-cell sequencing. The key protein expression was measured with Immunohistochemistry and immunofluorescence staining. RESULTS: In HFpEF hearts, myocardial fibroblasts exhibited higher levels of fibrosis. Furthermore, an increased number of fibroblasts differentiated into high-metabolism and high-fibrosis phenotypes. The expression levels of genes encoding certain pro-angiogenic secreted proteins were decreased in the HFpEF group, as confirmed by bulk RNA sequencing. Additionally, the proportion of the endothelial cell (EC) lineages in the HFpEF group was significantly downregulated, with low angiogenesis and high apoptosis phenotypes observed in these EC lineages. Interestingly, the fibroblasts in the HFpEF heart might cross-link with the EC lineages via over-secretion of ANGPTL4, thus displaying an anti-angiogenic function. Immunohistochemistry and immunofluorescence staining then revealed the downregulation of vascular density and upregulation of ANGPTL4 expression in HFpEF hearts. Finally, we predicted ANGPTL4as a potential druggable target using DrugnomeAI. CONCLUSION: In conclusion, this study comprehensively characterized the angiogenesis impairment in HFpEF hearts at single-cell resolution and proposed that ANGPTL4 secretion by fibroblasts may be a potential mechanism underlying this angiogenic abnormality.

10.
mSphere ; 9(1): e0056423, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38170984

RESUMEN

The emergence of antibiotic-resistant and biofilm-producing Staphylococcus aureus isolates presents major challenges for treating staphylococcal infections. Biofilm inhibition is an important anti-virulence strategy. In this study, a novel maleimide-diselenide hybrid compound (YH7) was synthesized and demonstrated remarkable antimicrobial activity against methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) in both planktonic cultures and biofilms. The minimum inhibitory concentration (MIC) of YH7 for S. aureus isolates was 16 µg/mL. Quantification of biofilms demonstrated that the sub-MIC (4 µg/mL) of YH7 significantly inhibits biofilm formation in both MSSA and MRSA. Confocal laser scanning microscopy analysis further confirmed the biofilm inhibitory potential of YH7. YH7 also significantly suppressed bacterial adherence to A549 cells. Moreover, YH7 treatment significantly inhibited S. aureus colonization in nasal tissue of mice. Preliminary mechanistic studies revealed that YH7 exerted potent biofilm-suppressing effects by inhibiting polysaccharide intercellular adhesin (PIA) synthesis, rather than suppressing bacterial autolysis. Real-time quantitative PCR data indicated that YH7 downregulated biofilm formation-related genes (clfA, fnbA, icaA, and icaD) and the global regulatory gene sarX, which promotes PIA synthesis. The sarX-dependent antibiofilm potential of YH7 was validated by constructing S. aureus NCTC8325 sarX knockout and complementation strains. Importantly, YH7 demonstrated a low potential to induce drug resistance in S. aureus and exhibited non-toxic to rabbit erythrocytes, A549, and BEAS-2B cells at antibacterial concentrations. In vivo toxicity assays conducted on Galleria mellonella further confirmed that YH7 is biocompatible. Overall, YH7 demonstrated potent antibiofilm activity supports its potential as an antimicrobial agent against S. aureus biofilm-related infections. IMPORTANCE Biofilm-associated infections, characterized by antibiotic resistance and persistence, present a formidable challenge in healthcare. Traditional antibacterial agents prove inadequate against biofilms. In this study, the novel compound YH7 demonstrates potent antibiofilm properties by impeding the adhesion and the polysaccharide intercellular adhesin production of Staphylococcus aureus. Notably, its exceptional efficacy against both methicillin-resistant and methicillin-susceptible strains highlights its broad applicability. This study highlights the potential of YH7 as a novel therapeutic agent to address the pressing issue of biofilm-driven infections.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Ratones , Conejos , Staphylococcus aureus , Staphylococcus aureus Resistente a Meticilina/genética , Meticilina/farmacología , Antibacterianos/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Biopelículas
11.
mSphere ; 9(1): e0061223, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38193656

RESUMEN

The emergence of Klebsiella pneumoniae carbapenemase-2 (KPC-2) and New Delhi metallo-ß-lactamase (NDM)-coproducing hypervirulent carbapenem-resistant Klebsiella pneumoniae (KPC-2-NDM-hv-CRKP) poses a certain threat to public health. Currently, only a few sporadic reports of such double-positive hv-CRKPs were available. In this study, we isolated two KPC-2-NDM-5-hv-CRKPs from elderly patients with serious underlying diseases and poor prognoses. We found both FK3122 and FK3127 were typical multidrug-resistant (MDR) isolates, exhibiting high-level resistance to both carbapenems and novel ß-lactamase inhibitors ceftazidime/avibactam. Notably, FK3122 is even resistant to cefiderocol due to multiple blaNDM-5 elements. Besides the MDR phenotype, A549 human lung epithelial cells and Galleria mellonella infection model all indicated that FK3122 and FK3127 were highly pathogenic. According to the whole-genome sequencing analysis, we observed over 10 resistant elements, and the uncommon co-existence of blaKPC-2, blaNDM-5, and virulence plasmids in both two isolates. Both virulence plasmids identified in FK3122 and FK3127 shared a high identity with classical virulence plasmid pK2044, harboring specific hypervirulent factors: rmpA and iuc operon. We also found that the resistance and virulence plasmids in FK3127 could not only be transferred to Escherichia coli EC600 independently but also together as a co-transfer, which was additionally confirmed by the S1-pulsed-field gel electrophoresis plasmid profile. Moreover, polymorphic mobile genetic elements were found surrounding resistance genes, which may stimulate the mobilization of resistance genes and result in the duplication of these elements. Considering the combination of high pathogenicity, limited therapy options, and easy transmission of KPC-2-NDM-5-hv-CRKP, our study emphasizes the need for underscores the imperative for ongoing surveillance of these pathogens.IMPORTANCEHypervirulent Klebsiella pneumoniae drug resistance has increased gradually with the emergence of carbapenem-resistant hypervirulent K. pneumoniae (hv-CRKP). However, little information is available on the virulence characteristics of the New Delhi metallo-ß-lactamase (NDM) and Klebsiella pneumoniae carbapenemase-2 (KPC-2) co-producing K. pneumoniae strains. In this study, we obtained two KPC-2-NDM-hv-CRKPs from elderly patients, each with distinct capsule types and sequence types: ST11-KL64 and ST15-KL24; these ST-type lineages are recognized as classical multidrug-resistant (MDR) K. pneumoniae. We found these KPC-2-NDM-hv-CRKPs were not only typical MDR isolates, including resistance to ceftazidime/avibactam and cefiderocol, but also displayed exceptionally high levels of pathogenicity. In addition, these high-risk factors can also be transferred to other isolates. Consequently, our study underscores the need for ongoing surveillance of these isolates due to their heightened pathogenicity, limited therapeutic options, and potential for easy transmission.


Asunto(s)
Compuestos de Azabiciclo , Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Klebsiella , Humanos , Anciano , Ceftazidima/farmacología , Klebsiella pneumoniae , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones por Klebsiella/epidemiología , Carbapenémicos/farmacología , Escherichia coli/genética
12.
Eur Radiol ; 34(7): 4831-4840, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38172441

RESUMEN

OBJECTIVES: Significant atherosclerotic stenosis or occlusion in the distal internal carotid artery (ICA) may induce diffuse wall thickening (DWT) in the upstream arterial wall. This study aimed to assess the association of atherosclerotic steno-occlusive diseases in the distal ICA with DWT in the upstream ipsilateral ICA. METHODS: Individuals with atherosclerotic stenosis in the distal ICA, detected by carotid MR vessel wall imaging using 3D pre- and post-contrast T1 volume isotropic turbo spin-echo acquisition (T1-VISTA) sequence, were enrolled. The associations of vessel wall thickening, the longitudinal extent of DWT, enhancement of the upstream ipsilateral ICA, and stenosis degree in the distal ICA were examined. RESULTS: Totally 64 arteries in 55 patients with atherosclerotic steno-occlusive distal ICAs were included. Significant correlations were found between distal ICA stenosis and DWT in the petrous ICA (r = 0.422, p = 0.001), DWT severity (r = 0.474, p < 0.001), the longitudinal extent of DWT in the ICA (r = 0.671, p < 0.001), enhancement in the petrous ICA (r = 0.409, p = 0.001), and enhancement degree (r = 0.651, p < 0.001). In addition, high degree of enhancement was correlated with both increased wall thickness and increased prevalence of DWT in the petrous ICA (both p < 0.001). CONCLUSIONS: DWT of the petrous ICA is commonly detected in patients with atherosclerotic steno-occlusive disease in the distal ICA. The degree of stenosis in the distal ICA is associated with wall thickening and its longitudinal extent in the upstream segments. CLINICAL RELEVANCE STATEMENT: Diffuse wall thickening is a common secondary change in atherosclerotic steno-occlusive disease in the intracranial carotid. This phenomenon constitutes a confounding factor in the distinction between atherosclerosis and inflammatory vasculopathies, and could be reversed after alleviated atherosclerotic stenosis. KEY POINTS: • Diffuse wall thickening of the petrous internal carotid artery is commonly detected in patients with atherosclerotic steno-occlusive disease in the distal internal carotid artery. • The phenomenon of diffuse wall thickening could be reversed after stenosis alleviation. • Carotid artery atherosclerosis with diffuse wall thickening should warrant a differential diagnosis from other steno-occlusive diseases, including moyamoya diseases and Takayasu aortitis.


Asunto(s)
Arteria Carótida Interna , Estenosis Carotídea , Humanos , Femenino , Masculino , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/complicaciones , Persona de Mediana Edad , Arteria Carótida Interna/diagnóstico por imagen , Arteria Carótida Interna/patología , Anciano , Angiografía por Resonancia Magnética/métodos , Adulto , Imagenología Tridimensional/métodos , Anciano de 80 o más Años
13.
Eur J Radiol ; 170: 111208, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37988960

RESUMEN

PURPOSE: This study aimed to investigate the associations of atherosclerotic plaque characteristics in intracranial and extracranial carotid arteries with severity of white matter hyperintensities (WMHs) in symptomatic patients using magnetic resonance (MR) imaging. METHOD: Patients with cerebrovascular symptoms and carotid plaque were recruited from the cross-sectional, multicenter study of CARE-II. Luminal stenosis of intracranial and extracranial carotid arteries, carotid plaque compositional features, and WMHs were evaluated by brain structural and vascular MR imaging. The atherosclerotic plaque characteristics in intracranial and extracranial carotid arteries were compared between patients with and without moderate-to-severe WMHs (Fazekas score > 2), and their associations with severity of WMHs were analyzed using logistic regression. RESULTS: Of the recruited 622 patients (mean age, 58.7 ± 10.9 years; 422 males), 221 (35.5 %) had moderate-to-severe WMHs with higher prevalence of moderate-to-severe luminal stenosis (17.0 % vs. 10.4 %), intraplaque hemorrhage (15.7 % vs. 9.0 %), thin/ruptured fibrous cap (30.2 % vs. 20.4 %), calcification (44.4 % vs. 22.2 %) and lipid-rich necrotic core (63.8 % vs. 51.1 %) in carotid artery compared to those without (all P < 0.05). Multivariate logistic regression showed that carotid calcification (OR, 1.854; 95 % CI, 1.187-2.898; P = 0.007) was independently associated with moderate-to-severe WMHs after adjusting for confounding factors. No significant association was found between intracranial atherosclerotic stenosis and moderate-to-severe WMHs (P > 0.05). CONCLUSION: Carotid atherosclerotic plaque features, particularly presence of calcification, were independently associated with severity of WMHs, but such association was not found in intracranial atherosclerotic stenosis, suggesting that carotid atherosclerotic plaque characteristics may have closer association with severity of WMHs compared to intracranial atherosclerosis.


Asunto(s)
Estenosis Carotídea , Arteriosclerosis Intracraneal , Placa Aterosclerótica , Sustancia Blanca , Masculino , Humanos , Persona de Mediana Edad , Anciano , Placa Aterosclerótica/diagnóstico por imagen , Constricción Patológica/patología , Estenosis Carotídea/patología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Estudios Transversales , Factores de Riesgo , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/patología , Imagen por Resonancia Magnética/métodos , Arteriosclerosis Intracraneal/patología
14.
Comput Methods Programs Biomed ; 244: 107975, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38128464

RESUMEN

BACKGROUND AND OBJECTIVE: Intracranial aneurysms are relatively common life-threatening diseases, and assessing aneurysm rupture risk and identifying the associated risk factors is essential. Parameters such as the Oscillatory Shear Index, Pressure Loss Coefficient, and Wall Shear Stress are reliable indicators of intracranial aneurysm development and rupture risk, but aneurysm surface irregular pulsation has also received attention in aneurysm rupture risk assessment. METHODS: The present paper proposed a new approach to estimate aneurysm surface deformation. This method transforms the estimation of aneurysm surface deformation into a constrained optimization problem, which minimizes the error between the displacement estimated by the model and the sparse data point displacements from the four-dimensional CT angiography (4D-CTA) imaging data. RESULTS: The effect of the number of sparse data points on the results has been discussed in both simulation and experimental results, and it shows that the proposed method can accurately estimate the surface deformation of intracranial aneurysms when using sufficient sparse data points. CONCLUSIONS: Due to a potential association between aneurysm rupture and surface irregular pulsation, the estimation of aneurysm surface deformation is needed. This paper proposed a method based on 4D-CTA imaging data, offering a novel solution for the estimation of intracranial aneurysm surface deformation.


Asunto(s)
Aneurisma Roto , Aneurisma Intracraneal , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Angiografía Cerebral/métodos , Tomografía Computarizada Cuatridimensional/métodos , Simulación por Computador , Medición de Riesgo , Aneurisma Roto/diagnóstico por imagen
15.
Eur Radiol ; 34(7): 4610-4618, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38108888

RESUMEN

OBJECTIVES: In patients with an unruptured intracranial aneurysm, gadolinium enhancement of the aneurysm wall is associated with growth and rupture. However, most previous studies did not have a longitudinal design and did not adjust for aneurysm size, which is the main predictor of aneurysm instability and the most important determinant of wall enhancement. We investigated whether aneurysm wall enhancement predicts aneurysm growth and rupture during follow-up and whether the predictive value was independent of aneurysm size. MATERIALS AND METHODS: In this multicentre longitudinal cohort study, individual patient data were obtained from twelve international cohorts. Inclusion criteria were as follows: 18 years or older with ≥ 1 untreated unruptured intracranial aneurysm < 15 mm; gadolinium-enhanced aneurysm wall imaging and MRA at baseline; and MRA or rupture during follow-up. Patients were included between November 2012 and November 2019. We calculated crude hazard ratios with 95%CI of aneurysm wall enhancement for growth (≥ 1 mm increase) or rupture and adjusted for aneurysm size. RESULTS: In 455 patients (mean age (SD), 60 (13) years; 323 (71%) women) with 559 aneurysms, growth or rupture occurred in 13/194 (6.7%) aneurysms with wall enhancement and in 9/365 (2.5%) aneurysms without enhancement (crude hazard ratio 3.1 [95%CI: 1.3-7.4], adjusted hazard ratio 1.4 [95%CI: 0.5-3.7]) with a median follow-up duration of 1.2 years. CONCLUSIONS: Gadolinium enhancement of the aneurysm wall predicts aneurysm growth or rupture during short-term follow-up, but not independent of aneurysm size. CLINICAL RELEVANCE STATEMENT: Gadolinium-enhanced aneurysm wall imaging is not recommended for short-term prediction of growth and rupture, since it appears to have no additional value to conventional predictors. KEY POINTS: • Although aneurysm wall enhancement is associated with aneurysm instability in cross-sectional studies, it remains unknown whether it predicts risk of aneurysm growth or rupture in longitudinal studies. • Gadolinium enhancement of the aneurysm wall predicts aneurysm growth or rupture during short-term follow-up, but not when adjusting for aneurysm size. • While gadolinium-enhanced aneurysm wall imaging is not recommended for short-term prediction of growth and rupture, it may hold potential for aneurysms smaller than 7 mm.


Asunto(s)
Aneurisma Roto , Medios de Contraste , Gadolinio , Aneurisma Intracraneal , Angiografía por Resonancia Magnética , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Femenino , Masculino , Estudios Longitudinales , Aneurisma Roto/diagnóstico por imagen , Persona de Mediana Edad , Angiografía por Resonancia Magnética/métodos , Anciano , Estudios de Cohortes
16.
Dalton Trans ; 52(46): 17470-17476, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37953713

RESUMEN

The electrochemical nitrate reduction reaction (ENO3RR) is a green ammonia synthesis method under ambient conditions relative to the traditional Haber-Bosch technology, which does not require high-temperature or high-pressure conditions and can convert nitrate pollutants in the environment into value-added NH3, thus achieving a dual purpose. However, more electrocatalysts with a remarkable performance towards high-efficiency ENO3RR need to be developed. In this work, a Cu/NiO-NF composite electrocatalyst with a nanorod structure on nickel foam was successfully fabricated, which contains heterogeneous interfaces between Cu and NiO toward selective electrocatalytic nitrate reduction for ammonia synthesis. The steric nanorod morphology of the catalyst can significantly increase the surface area, expose more active sites, and improve the reaction activity. Moreover, the construction of the composite and the interface effectively boosts the synergistic effect of the active species Cu and NiO, which can regulate the electronic structure of the catalyst, expose more active sites, enhance the conductivity of the material, and accelerate the interfacial electron transfer, thereby further promoting the ENO3RR performance. This Cu/NiO-NF composite exhibits a high NH3 yield of 0.6 mmol h-1 cm-2 and up to 97.81% faradaic efficiency at the optimal applied potential of -1.0 V (vs. RHE) in a concentration of 0.1 M NO3--containing 0.1 M PBS. Furthermore, it demonstrates excellent electrochemical cycle stability. This work provides insights into the rational design and fabrication of ENO3RR electrocatalysts for potential electrocatalytic applications.

17.
Prog Neurobiol ; 231: 102543, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37924858

RESUMEN

Tinnitus induced by hearing loss is caused primarily by irreversible damage to the peripheral auditory system, which results in abnormal neural responses and frequency map disruption in the central auditory system. It remains unclear whether and how electrical rehabilitation of the auditory cortex can alleviate tinnitus. We hypothesize that stimulation of the cortical surface can alleviate tinnitus by enhancing neural responses and promoting frequency map reorganization. To test this hypothesis, we assessed and activated cortical maps using our newly designed graphene-based electrode array with a noise-induced tinnitus animal model. We found that cortical surface stimulation increased cortical activity, reshaped sensory maps, and alleviated hearing loss-induced tinnitus behavior in adult mice. These effects were likely due to retained long-term synaptic potentiation capabilities, as shown in cortical slices from the mice model. These findings suggest that cortical surface activation can be used to facilitate practical functional recovery from phantom percepts induced by sensory deprivation. They also provide a working principle for various treatment methods that involve electrical rehabilitation of the cortex.


Asunto(s)
Corteza Auditiva , Pérdida Auditiva , Acúfeno , Ratones , Animales , Acúfeno/terapia , Modelos Animales de Enfermedad , Mapeo Encefálico/métodos , Plasticidad Neuronal/fisiología
18.
Front Comput Neurosci ; 17: 1231924, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38024449

RESUMEN

Introduction: The N-methyl-D-aspartate receptor (NMDAR) plays a critical role in synaptic transmission and is associated with various neurological and psychiatric disorders. Recently, a novel form of postsynaptic plasticity known as NMDAR-based short-term postsynaptic plasticity (STPP) has been identified. It has been suggested that long-lasting glutamate binding to NMDAR allows for the retention of input information in brain slices up to 500 ms, leading to response facilitation. However, the impact of STPP on the dynamics of neuronal populations remains unexplored. Methods: In this study, we incorporated STPP into a continuous attractor neural network (CANN) model to investigate its effects on neural information encoding in populations of neurons. Unlike short-term facilitation, a form of presynaptic plasticity, the temporally enhanced synaptic efficacy resulting from STPP destabilizes the network state of the CANN by increasing its mobility. Results: Our findings demonstrate that the inclusion of STPP in the CANN model enables the network state to predictively respond to a moving stimulus. This nontrivial dynamical effect facilitates the tracking of the anticipated stimulus, as the enhanced synaptic efficacy induced by STPP enhances the system's mobility. Discussion: The discovered STPP-based mechanism for sensory prediction provides valuable insights into the potential development of brain-inspired computational algorithms for prediction. By elucidating the role of STPP in neural population dynamics, this study expands our understanding of the functional implications of NMDAR-related plasticity in information processing within the brain. Conclusion: The incorporation of STPP into a CANN model highlights its influence on the mobility and predictive capabilities of neural networks. These findings contribute to our knowledge of STPP-based mechanisms and their potential applications in developing computational algorithms for sensory prediction.

19.
Food Chem X ; 19: 100871, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37780239

RESUMEN

The beneficial microorganisms in food are diverse and complex in structure. These beneficial microorganisms can produce different and unique flavors in the process of food fermentation. The unique flavor of these fermented foods is mainly produced by different raw and auxiliary materials, fermentation technology, and the accumulation of flavor substances by dominant microorganisms during fermentation. The succession and metabolic accumulation of microbial flora significantly impacts the distinctive flavor of fermented foods. The investigation of the role of microbial flora changes in the production of flavor substances during fermentation can reveal the potential connection between microbial flora succession and the formation of key flavor compounds. This paper reviewed the evolution of microbial flora structure as food fermented and the key volatile compounds that contribute to flavor in the food system and their potential relationship. Further, it was a certain guiding significance for food industrial production.

20.
Microbiol Spectr ; 11(6): e0159623, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37819121

RESUMEN

IMPORTANCE: Biofilms are an important virulence factor in Staphylococcus aureus and are characterized by a structured microbial community consisting of bacterial cells and a secreted extracellular polymeric matrix. Inhibition of biofilm formation is an effective measure to control S. aureus infection. Here, we have synthesized a small molecule compound S-342-3, which exhibits potent inhibition of biofilm formation in both MRSA and MSSA. Further investigations revealed that S-342-3 exerts inhibitory effects on biofilm formation by reducing the production of polysaccharide intercellular adhesin and preventing bacterial adhesion. Our study has confirmed that the inhibitory effect of S-342-3 on biofilm is achieved by downregulating the expression of genes responsible for biofilm formation. In addition, S-342-3 is non-toxic to Galleria mellonella larvae and A549 cells. Consequently, this study demonstrates the efficacy of a biologically safe compound S-342-3 in inhibiting biofilm formation in S. aureus, thereby providing a promising antibiofilm agent for further research.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Staphylococcus aureus/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Biopelículas , Adhesión Bacteriana , Staphylococcus aureus Resistente a Meticilina/metabolismo , Antibacterianos/farmacología , Antibacterianos/metabolismo , Pruebas de Sensibilidad Microbiana
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