Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 121(23): e2322283121, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38814873

RESUMEN

Single-atom catalysts (SACs) with atomic dispersion active sites have exhibited huge potentials in peroxymonosulfate (PMS)-based Fenton-like chemistry in water purification. However, four-N coordination metal (MN4) moieties often suffer from such problems as low selectivity and narrow workable pH. How to construct SACs in a controllable strategy with optimized electronic structures is of great challenge. Herein, an innovative strategy (i.e., the "4 + 1" fabrication) was devised to precisely modulate the first-shell coordinated microenvironment of FeN4 SAC using an additional N (SA-FeN5). This leads to almost 100% selective formation of high-valent iron-oxo [Fe(IV)═O] (steady-state concentration: 2.00 × 10-8 M) in the SA-FeN5/PMS system. In-depth theoretical calculations unveil that FeN5 configuration optimizes the electron distribution of monatomic Fe sites, which thus fosters PMS adsorption and reduces the energy barrier for Fe(IV)═O generation. SA-FeN5 was then attached to polyvinylidene difluoride membrane for a continuous flow device, showing long-term abatement of the microcontaminant. This work furnishes a general strategy for effective PMS activation and selective high-valent metal-oxo species generation by high N-coordination number regulation in SACs, which would provide guidance in the rational design of superior environmental catalysts for water purification.

2.
Exp Neurol ; 377: 114784, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38642665

RESUMEN

Inflammation is one of the key injury factors for spinal cord injury (SCI). Exosomes (Exos) derived from M2 macrophages have been shown to inhibit inflammation and be beneficial in SCI animal models. However, lacking targetability restricts their application prospects. Considering that chemokine receptors increase dramatically after SCI, viral macrophage inflammatory protein II (vMIP-II) is a broad-spectrum chemokine receptor binding peptide, and lysosomal associated membrane protein 2b (Lamp2b) is the key membrane component of Exos, we speculated that vMIP-II-Lamp2b gene-modified M2 macrophage-derived Exos (vMIP-II-Lamp2b-M2-Exo) not only have anti-inflammatory properties, but also can target the injured area by vMIP-II. In this study, using a murine contusive SCI model, we revealed that vMIP-II-Lamp2b-M2-Exo could target the chemokine receptors which highly expressed in the injured spinal cords, inhibit some key chemokine receptor signaling pathways (such as MAPK and Akt), further inhibit proinflammatory factors (such as IL-1ß, IL-6, IL-17, IL-18, TNF-α, and iNOS), and promote anti-inflammatory factors (such as IL-4 and Arg1) productions, and the transformation of microglia/macrophages from M1 into M2. Moreover, the improved histological and functional recoveries were also found. Collectively, our results suggest that vMIP-II-Lamp2b-M2-Exo may provide neuroprotection by targeting the injured spinal cord, inhibiting some chemokine signals, reducing proinflammatory factor production and modulating microglia/macrophage polarization.


Asunto(s)
Exosomas , Macrófagos , Ratones Endogámicos C57BL , Microglía , Traumatismos de la Médula Espinal , Animales , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/genética , Exosomas/metabolismo , Exosomas/trasplante , Ratones , Macrófagos/metabolismo , Microglía/metabolismo , Microglía/efectos de los fármacos , Microglía/patología , Proteína 2 de la Membrana Asociada a los Lisosomas/metabolismo , Proteína 2 de la Membrana Asociada a los Lisosomas/genética , Polaridad Celular/efectos de los fármacos , Polaridad Celular/fisiología , Femenino , Neuroprotección/fisiología , Transducción de Señal/efectos de los fármacos , Quimiocinas/metabolismo
3.
J Magn Reson Imaging ; 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38174777

RESUMEN

BACKGROUND: Conventional magnetic resonance imaging (MRI) has certain limitations in distinguishing between malignant and benign urinary bladder (UB) lesions. Amide proton transfer (APT) imaging may provide more diagnostic information than diffusion-weighted imaging (DWI) to distinguish between malignant and benign UB. PURPOSE: To investigate the potential of APT imaging in the diagnosis of malignant and benign UB lesions and to compare its diagnostic efficacy with that of conventional DWI. STUDY TYPE: Prospective. SUBJECTS: Eighty patients with UB lesions. FIELD STRENGTH/SEQUENCE: A 3.0 T/turbo spin echo (TSE) T1-weighted and T2-weighted imaging, single-shot echo planar DWI, and three-dimensional TSE APT imaging. ASSESSMENT: Patients underwent radical cystectomy or transurethral resection of the bladder lesions within 2 weeks after CT urography and MRI examination. APT signal intensity in UB lesions was quantified by the asymmetric magnetization transfer ratio (MTRasym ). MTRasym and apparent diffusion coefficient (ADC) values were measured and compared between malignant and benign UB lesions. STATISTICAL TESTS: Kolmogorov-Smirnov test, Student's t test or Mann-Whitney U test, Spearman rank correlation coefficient, area under the receiver operating characteristic (ROC) curve (AUC), Delong test, and intraclass correlation coefficient (ICC). The significance threshold was set at P < 0.05. RESULTS: Thirty-two patients had pathologically confirmed benign UB lesions, including 2 bladder leiomyomas, 1 submucosal amyloidosis, 1 inflammatory myofibroblastic tumor, and 28 inflammatory lesions, and 48 patients had pathologically confirmed urothelial carcinoma. Urothelial carcinomas showed significantly higher MTRasym values (1.53% [0.74%] vs. 0.85% [0.23%]) and significantly lower ADC values (1.24 ± 0.34 × 10-3 mm2 /s vs. 1.43 ± 0.22 × 10-3 mm2 /s) than benign UB lesions. The MTRasym value (AUC = 0.928) was significantly better in differentiating urothelial carcinoma from benign UB lesions than the ADC value (AUC = 0.722). DATA CONCLUSION: APT imaging may have value in discriminating malignant from benign UB lesions and has better diagnostic performance than DWI. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

4.
J Colloid Interface Sci ; 657: 155-168, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38035418

RESUMEN

The global shortage of freshwater and inadequate supply of clean water have necessitated the implementation of robust technologies for wastewater purification, and Fenton-like chemistry is a highly-promising approach. However, realizing the rapid Fenton-like chemistry for high-efficiency degradation of organic micropollutants (OMs) remains challenging. Herein, one novel system was constructed by a Co single-atom catalyst activating peroxymonosulfate (PMS), and the optimal system (SA-Co-NBC-0.2/PMS) achieved unprecedented catalytic performance towards a model OM [Iohexol (IOH)], i.e., almost 100% decay ratio in only 10 min (the observed rate constant: 0.444 min-1) with high electrophilic species 1O2 (singlet oxygen) generation. Theoretical calculations unveiled that Co-N4 sites preferred to adsorb the terminal-O of PMS (more negative adsorption energy than other O sites: -32.67 kcal/mol), promoting the oxidation of PMS to generate 1O2. Iodine (I)23 (0.1097), I24 (0.1154) and I25 (0.0898) on IOH with higher f- electrophilic values were thus identified as the main attack sites. Furthermore, 16S ribosomal RNA high-throughput sequencing and quantitative structure-activity relationship analysis illustrated the environmentally-benign property of the SA-Co-NBC-0.2 and the tapering ecological risk during IOH degradation process. Significantly, this work comprehensively checked the competence of the SA-Co-NBC-0.2/PMS system for organics abatement in practical wastewater.


Asunto(s)
Cobalto , Yohexol , Adsorción , Catálisis , Peróxidos
5.
Front Pediatr ; 11: 1169733, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37469682

RESUMEN

Background: Studies have found that toxic heavy metals exposure could induce the generation of reactive oxygen species (ROS), and is of epigenetic effect, which might be associated with the occurrence of Autistic Disorder (ASD). This systematic review and meta-analysis aims to elucidate the association between exposure to 4 heavy metals, cadmium (Cd), lead (Pb), arsenic(As), and mercury (Hg), and the occurrence of ASD in children. Methods: We searched PubMed, Web of Science, Embase, and Cochrane Library, from their inception to October 2022, for epidemiological investigations that explore the association between exposure to Cd, Pb, As, or Hg and the occurrence of child ASD. Results: A total of 53 studies were included, involving 5,054 individuals aged less than 18 (2,533 ASD patients and 2,521 healthy controls). Compared with the healthy controls, in hair and blood tests, concentrations of the 4 heavy metals were significantly higher in the ASD group than in the healthy control group, and the differences in Pb, arsenic and Hg were statistically significant (P < 0.05). In the urine test, concentrations of arsenic and Hg were significantly higher in the ASD group than in the healthy control group (P < 0.05), while the results of Cd and Pb were opposite to those of arsenic and Hg (P > 0.05). Subgroup analysis for geographic regions showed that ASD patients in Asia and Europe had higher concentrations of the 4 heavy metals, compared with the healthy controls, in which the differences in Pb, arsenic, and Hg were statistically significant (P < 0.05), while in North America, the healthy controls had higher Cd, arsenic, and Hg concentrations (P > 0.05). Conclusion: Compared with the healthy control group, the ASD group had higher concentrations of Cd, Pb, arsenic, and Hg. These 4 heavy metals play different roles in the occurrence and progression of ASD. Moreover, there is significant heterogeneity among the included studies due to controversies about the study results among different countries and regions and different sources of detection materials. The results of this study firmly support the policies to limit heavy metals exposure, especially among pregnant women and young children, so as to help reduce the incidence of ASD.

6.
Medicine (Baltimore) ; 102(22): e33771, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37266626

RESUMEN

BACKGROUND: To evaluate the effect of repetitive transcranial magnetic stimulation (rTMS) combined with task-oriented training (TOT) on upper limb function in stroke patients with hemiplegia. METHODS: A systematic review and meta-analysis was performed using PRISMA guidelines. Computer searches of PubMed, Cochrane Library, Embase, Web of science, China Knowledge Network, Wanfang, and Wipu databases were conducted from the time of database creation to October 27, 2022. Clinical trials meeting the inclusion criteria were screened, with rTMS combined with TOT in the test group and other therapies in the control group. Literature screening and data extraction were performed independently by 2 investigators, and meta-analysis was performed using Stata software after quality evaluation of the literature. RESULTS: Meta-analysis results showed that repeated transcranial magnetic stimulation combined with TOT was more effective in box and block test (I2 = 0%, P = .820, 95% confidence interval [CI] [-0.20, 0.88]), Fugl-Meyer Assessment (I2 = 0%, P = .569, 95% CI [0.88, 1.26]), and modified Barthel Index (I2 = 39.9%, P = .189, 95% CI [0.45, 1.03]) were not significantly different from controls, and the efficacy was significantly better in motor evoked potentials (I2 = 86.5%, P < .001, 95% CI [-1.38, -0.83]). CONCLUSIONS: Data analysis clarified the efficacy of rTMS) combined with TOT on upper extremity motor function disorders after stroke, but there was no significant difference between the efficacy in box and block test, Fugl-Meyer Assessment, and modified Barthel Index and the efficacy in motor evoked potentials between rTMS and the control group, suggesting that the neuro plasticizing effect of rTMS may translate into functional improvement by promoting neuro electrical signaling.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Estimulación Magnética Transcraneal/métodos , Hemiplejía/etiología , Hemiplejía/terapia , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/terapia , Extremidad Superior
7.
Front Psychol ; 14: 1128686, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37008858

RESUMEN

Today's civilization faces serious challenges related to sustainability. Without the support of society, organizations can no longer continually build their enterprises. The pressure of sustainable development goals are also enhancing on companies. Thus, marketing managers place a strong emphasis on meeting the socio-ethical demands of their target audience, whether it is through cultural promotion, environmental conservation, or disaster relief initiatives. This study explores how sustainable marketing influences the customer engagement and sustainable purchase intention. For data collection, a self-administered questionnaire was distributed to 393 purchasers and potential purchasers of electric vehicles, and a structural equation model (SEM) test was conducted using Mplus 8.0 software. The results of the study showed that: First, the outcome states that sustainable marketing valuable for improving brand image. Second, brand image is good for customer engagement in the Chinese market for electric automobiles. Third, the appeal of sustainable purchasing intentions is increased by brand image. Fourth, a useful instrument for long-term purchase intentions is customer engagement. Fifth, CSR has a significant role in enhancing consumers' intentions to make sustainable purchases. Most notably, it acts as a helpful moderator in the relationship between company image and customer engagement. Lastly, CSR also strengthens the link between company image and sustainable purchasing intentions. This research offers a theoretical framework and practical implications that sustainable marketing initiatives are an important antecedent of organizational outcomes for the electric vehicle sector in China.

8.
Medicine (Baltimore) ; 102(12): e33393, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36961150

RESUMEN

The etiology of adolescent myopia involves genetic and environmental factors. The pathological mechanism of modern medicine includes blood perfusion, changes in blood molecules, neurotransmitters, and sclera remodeling. Chinese medicine believes that myopia is mainly related to the deficiency of liver blood and spleen and stomach disorders. The prevention and treatment of myopia in adolescents are very important, but in terms of the current incidence of myopia in adolescents and the level of clinical diagnosis and treatment, its prevention and treatment are insufficient. Modern medicine and traditional Chinese medicine both pay attention to integrity, so adolescent myopia should not only pay attention to eye changes but also pay attention to other body systems and other aspects of change. Intestinal flora has become a research hotspot in recent years, and it has been found that it is closely associated with multi-system and multi-type diseases. No studies have directly investigated the link between Intestinal flora and myopia in adolescents. Therefore, by summarizing the pathological mechanism of adolescent myopia and the connection between intestinal flora and the pathological mechanism of adolescent myopia, this paper analyzes the possible pathological mechanism of the influence of intestinal flora on adolescent myopia, providing a theoretical basis for future studies on the correlation between changes of intestinal flora and its metabolites and the incidence of adolescent myopia, which is of great significance for the study on the risk prediction of adolescent myopia.


Asunto(s)
Microbioma Gastrointestinal , Miopía , Humanos , Adolescente , Miopía/epidemiología , Miopía/etiología , Medicina Tradicional China , Pueblo Asiatico , Esclerótica
9.
PeerJ ; 11: e14929, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36846458

RESUMEN

Background: Following spinal cord injury (SCI), a large number of peripheral monocytes infiltrate into the lesion area and differentiate into macrophages (Mø). These monocyte-derived Mø are very difficult to distinguish from the local activated microglia (MG). Therefore, the term Mø/MG are often used to define the infiltrated Mø and/or activated MG. It has been recognized that pro-inflammatory M1-type Mø/MG play "bad" roles in the SCI pathology. Our recent research showed that local M1 cells are mainly CD45-/lowCD68+CD11b+ in the subacute stage of SCI. Thus, we speculated that the M1 cells in injured spinal cords mainly derived from MG rather than infiltrating Mø. So far, their dynamics following SCI are not yet entirely clear. Methods: Female C57BL/6 mice were used to establish SCI model, using an Infinite Horizon impactor with a 1.3 mm diameter rod and a 50 Kdynes force. Sham-operated (sham) mice only underwent laminectomy without contusion. Flow cytometry and immunohistofluorescence were combined to analyze the dynamic changes of polarized Mø and MG in the acute (1 day), subacute (3, 7 and 14 days) and chronic (21 and 28 days) phases of SCI. Results: The total Mø/MG gradually increased and peaked at 7 days post-injury (dpi), and maintained at high levels 14, 21 and 28 dpi. Most of the Mø/MG were activated, and the Mø increased significantly at 1 and 3 dpi. However, with the pathological process, activated MG increased nearly to 90% at 7, 14, 21 and 28 dpi. Both M1 and M2 Mø were increased significantly at 1 and 3 dpi. However, they decreased to very low levels from 7 to 28 dpi. On the contrary, the M2-type MG decreased significantly following SCI and maintained at a low level during the pathological process.


Asunto(s)
Microglía , Traumatismos de la Médula Espinal , Femenino , Ratones , Animales , Microglía/patología , Ratones Endogámicos C57BL , Macrófagos/patología , Traumatismos de la Médula Espinal/patología
10.
Front Mol Neurosci ; 15: 848185, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35663270

RESUMEN

Proinflammatory immune cell subsets constitute the majority in the local microenvironment after spinal cord injury (SCI), leading to secondary pathological injury. Previous studies have demonstrated that inflammasomes act as an important part of the inflammatory process after SCI. Probenecid, an inhibitor of the Pannexin-1 channel, can inhibit the activation of inflammasomes. This article focuses on the effects of probenecid on the local immune microenvironment, histopathology, and behavior of SCI. Our data show that probenecid inhibited the expression and activation of nucleotide-binding oligomerization domain receptor pyrindomain-containing 1 (NLRP1), apoptosis-associated speck-like protein containing a CARD (ASC) and caspase-1, interleukin-1ß (IL-1ß), and caspase-3 proteins associated with inflammasomes, thereby suppressing the proportion of M1 cells. And consequently, probenecid reduced the lesion area and demyelination in SCI. Moreover, the drug increased the survival of motor neurons, which resulted in tissue repair and improved locomotor function in the injured SC. Altogether, existing studies indicated that probenecid can alleviate inflammation by blocking Pannexin-1 channels to inhibit the expression of caspase-1 and IL-1ß, which in turn restores the balance of immune cell subsets and exerts neuroprotective effects in rats with SCI.

11.
Magn Reson Imaging ; 92: 26-32, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35623417

RESUMEN

PURPOSE: To investigate the feasibility of susceptibility weighted imaging (SWI) in detecting tumour boundaries in metastatic liver disease (MLD) without contrast agent, and whether SWI can provide pathophysiologic information for preoperative evaluation. METHODS: Thirty patients with MLD underwent tumour resection. All patients underwent conventional MRI (T1-weighted and T2-weighted imaging), contrast-enhanced (CE) MRI and multibreath-hold 2D SWI. The conspicuity of the tumour boundary was assessed using a 4-grade scale. The detection rate of tumour boundaries and areas were reviewed and measured. The longest dimension was used to estimate the tumour size from the MR image. The conspicuity of the tumour boundary and area were compared using a nonparametric multi-group comparison (Friedman M). The McNemar test was applied to examine differences in the detection rate of tumour boundaries. RESULTS: Among four different MRI sequences, SWI exhibited increased conspicuity of the tumour boundary than the conventional MRI (P < 0.001). SWI (91.8%) and CE-MRI (64.4%) exhibited higher detection rates of the tumour boundary than T1WI and T2WI (6.8% and 12.3% respectively). Longer tumour maximum diameters were measured with SWI (29.1 ± 17.2 mm) and CE-MRI (28.2 ± 16.8) compared to conventional MRI (P < 0.05). CONCLUSION: 2D multibreath-hold SWI enables enhanced noninvasive detection of tumour boundaries in patients with MLD compared with conventional MRI and CE-MRI without using an exogenous contrast agent. SWI has the potential to become a preoperative assessment standard that complements conventional MRI.


Asunto(s)
Hepatopatías , Neoplasias , Medios de Contraste , Humanos , Imagen por Resonancia Magnética/métodos , Sensibilidad y Especificidad
12.
Epilepsy Res ; 133: 6-9, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28395176

RESUMEN

The high-fat, low-carbohydrate ketogenic diet (KD) is an effective clinical treatment for epilepsy in juveniles, especially for drug-resistant seizures. The KD results in elevated production of ketone bodies (KB's), such as beta-hydroxybutyrate (ß-HB), which are thought to have anticonvulsant properties; however, their exact mechanism of action is unknown. In vitro, KB effects on reducing neuronal firing rates are mediated in part by Katp channel activity and GABAb signaling. In order to study metabolic and pharmacological effects in a whole-animal model, we used the eas "bang-sensitive" (BS) mutant strain of Drosophila, which exhibits seizure-like activity (SLA) upon mechanical stimulation. Direct application of the KB ß-HB to food reduced BS SLA. Application either of tolbutamide, a Katp blocker, or of CGP-55845, a GABAb antagonist, concomitantly with ß-HB, partially reversed these KB effects on SLA, verifying a role for Katp channels and GABAb signaling in mediating the anticonvulsant effects of KB's and validating this whole-animal model of KD effects on seizure.


Asunto(s)
Ácido 3-Hidroxibutírico/uso terapéutico , Anticonvulsivantes/uso terapéutico , Antagonistas del GABA/farmacología , Canales KATP/metabolismo , Receptores de GABA-B/metabolismo , Convulsiones/tratamiento farmacológico , Animales , Animales Modificados Genéticamente , Modelos Animales de Enfermedad , Proteínas de Drosophila/genética , Drosophila melanogaster , Hipoglucemiantes/farmacología , Canales KATP/genética , Ácidos Fosfínicos/farmacología , Propanolaminas/farmacología , Receptores de GABA-B/genética , Transducción de Señal/efectos de los fármacos , Estadísticas no Paramétricas , Tolbutamida/farmacología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...