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2.
Artículo en Inglés | MEDLINE | ID: mdl-38959195

RESUMEN

Background: Posterior fossa craniotomy is commonly performed for various pathologies. However, intra-cranial infection following craniotomy causes morbidity. Pseudomeningocele is one of the main complications following posterior fossa operation. This study aimed to test the hypothesis that the risk of intra-cranial infection is increased in patients who undergo posterior fossa craniotomy with pseudomeningocele compared with those without pseudomeningocele. Methods: We retrospectively analyzed the data of patients undergoing posterior fossa craniotomy for the management of neurological pathologies at our institute from 2011 to 2020. A total of 308 craniotomies were included, and the primary outcome of interest was the occurrence of intra-cranial infection. Standard statistical methods were used to explore associations between several parameters, including pseudomeningocele, intra-cranial infection, and wound leak. Results: Of the 308 craniotomies, 41 (13.3%) developed intra-cranial infection and 59 (19.2%) involved pseudomeningocele. Of cases involving pseudomeningocele, 27 (45.8%) developed an intra-cranial infection compared with only 14 of 249 without pseudomeningocele (5.6%; p < 0.001). In the multi-variable analysis, pseudomeningocele was associated with intra-cranial infection (odds ratio [OR] 8.56; 95% confidence interval [CI] 3.145-23.299; p < 0.001) and wound leak (OR 91.339; 95% CI 10.437-799.364; p < 0.001). Conclusion: The findings indicate that patients undergoing posterior fossa craniotomy are at a greater risk of intra-cranial infection if there is pseudomeningocele after the operation.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39031344

RESUMEN

Hepatocellular carcinoma (HCC) is the predominant form of primary liver cancer, accounting for approximately 90% of liver cancer cases. It currently ranks as the fifth most prevalent cancer worldwide and represents the third leading cause of cancer-related mortality. As a malignant disease with surgical resection and ablative therapy being the sole curative options available, it is disheartening that most HCC patients who undergo liver resection experience relapse within five years. Microvascular invasion (MVI), defined as the presence of micrometastatic HCC emboli within liver vessels, serves as an important histopathological feature and indicative factor for both disease-free survival and overall survival in HCC patients. Therefore, achieving accurate preoperative noninvasive prediction of MVI holds vital significance in selecting appropriate clinical treatments and improving patient prognosis. Currently, there are no universally recognized criteria for preoperative diagnosis of MVI in clinical practice. Consequently, extensive research efforts have been directed towards preoperative imaging prediction of MVI to address this problem and the relative research progresses were reviewed in this article to summarize its current limitations and future research prospects.

4.
Phytomedicine ; 132: 155833, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-39008915

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is the second most common cause of cancer-related mortality and is characterised by extensive invasive and metastatic potential. Previous studies have shown that vitexicarpin extracted from the fruits of Vitex rotundifolia can impede tumour progression. However, the molecular mechanisms involved in CRC treatment are still not fully established. PURPOSE: Our study aimed to investigate the anticancer activity, targets, and molecular mechanisms of vitexicarpin in CRC hoping to provide novel therapies for patients with CRC. STUDY DESIGN/METHODS: The impact of vitexicarpin on CRC was assessed through various experiments including MTT, clone formation, EDU, cell cycle, and apoptosis assays, as well as a tumour xenograft model. CETSA, label-free quantitative proteomics, and Biacore were used to identify the vitexicarpin targets. WB, Co-IP, Ubiquitination assay, IF, molecular docking, MST, and cell transfection were used to investigate the mechanism of action of vitexicarpin in CRC cells. Furthermore, we analysed the expression patterns and correlation of target proteins in TCGA and GEPIA datasets and clinical samples. Finally, wound healing, Transwell, tail vein injection model, and tissue section staining were used to demonstrate the antimetastatic effect of vitexicarpin on CRC in vitro and in vivo. RESULTS: Our findings demonstrated that vitexicarpin exhibits anticancer activity by directly binding to inosine monophosphate dehydrogenase 2 (IMPDH2) and that it promotes c-Myc ubiquitination by disrupting the interaction between IMPDH2 and c-Myc, leading to epithelial-mesenchymal transition (EMT) inhibition. Vitexicarpin hinders the migration and invasion of CRC cells by reversing EMT both in vitro and in vivo. Additionally, these results were validated by the overexpression and knockdown of IMPDH2 in CRC cells. CONCLUSION: These results demonstrated that vitexicarpin regulates the interaction between IMPDH2 and c-Myc to inhibit CRC proliferation and metastasis both in vitro and in vivo. These discoveries introduce potential molecular targets for CRC treatment and shed light on new mechanisms for c-Myc regulation in tumours.

5.
Neurocrit Care ; 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39043984

RESUMEN

BACKGROUND: Identical bursts on electroencephalography (EEG) are considered a specific predictor of poor outcomes in cardiac arrest, but its relationship with structural brain injury severity on magnetic resonance imaging (MRI) is not known. METHODS: This was a retrospective analysis of clinical, EEG, and MRI data from adult comatose patients after cardiac arrest. Burst similarity in first 72 h from the time of return of spontaneous circulation were calculated using dynamic time-warping (DTW) for bursts of equal (i.e., 500 ms) and varying (i.e., 100-500 ms) lengths and cross-correlation for bursts of equal lengths. Structural brain injury severity was measured using whole brain mean apparent diffusion coefficient (ADC) on MRI. Pearson's correlation coefficients were calculated between mean burst similarity across consecutive 12-24-h time blocks and mean whole brain ADC values. Good outcome was defined as Cerebral Performance Category of 1-2 (i.e., independence for activities of daily living) at the time of hospital discharge. RESULTS: Of 113 patients with cardiac arrest, 45 patients had burst suppression (mean cardiac arrest to MRI time 4.3 days). Three study participants with burst suppression had a good outcome. Burst similarity calculated using DTW with bursts of varying lengths was correlated with mean ADC value in the first 36 h after cardiac arrest: Pearson's r: 0-12 h: - 0.69 (p = 0.039), 12-24 h: - 0.54 (p = 0.002), 24-36 h: - 0.41 (p = 0.049). Burst similarity measured with bursts of equal lengths was not associated with mean ADC value with cross-correlation or DTW, except for DTW at 60-72 h (- 0.96, p = 0.04). CONCLUSIONS: Burst similarity on EEG after cardiac arrest may be associated with acute brain injury severity on MRI. This association was time dependent when measured using DTW.

6.
Int J Biol Macromol ; 273(Pt 2): 132990, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38857719

RESUMEN

Pseudomonas aeruginosa is a critical pathogen and novel treatments are urgently needed. The out membrane of P. aeruginosa facilitates biofilm formation and antibiotic resistance, and hinders the exogenous application against Gram-negative bacteria of endolysins. Engineered endolysins are investigated for enhancing antimicrobial activity, exemplified by artilysins. Nevertheless, existing research predominantly relies on laborious and time-consuming approaches of individually artilysin identification. This study proposes a novel strategy for expedited artilysin discovery using a recombinant artilysin library comprising proteins derived from 38 antimicrobial peptides and 8 endolysins. In this library, 19 colonies exhibited growth inhibition against P. aeruginosa exceeding 50 %, and three colonies were designated as dutarlysin-1, dutarlysin-2 and dutarlysin-3. Remarkably, dutarlysin-1, dutarlysin-2 and dutarlysin-3 demonstrated rapid and enhanced antibacterial activity, even minimum inhibitory concentration of them killed approximately 4.93 lg units, 6.75 lg units and 5.36 lg units P. aeruginosa, respectively. Dutarlysins were highly refractory to P. aeruginosa resistance development. Furthermore, 2 µmol/L dutarlysin-1 and dutarlysin-3 effectively eradicated over 76 % of the mature biofilm. These dutarlysins exhibited potential broad-spectrum activity against hospital susceptible Gram-negative bacteria. These results supported the effectiveness of this artilysins discovery strategy and suggested dutarlysin-1 and dutarlysin-3 could be promising antimicrobial agents for combating P. aeruginosa.


Asunto(s)
Antibacterianos , Biopelículas , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa , Pseudomonas aeruginosa/efectos de los fármacos , Biopelículas/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Proteínas Recombinantes/farmacología , Endopeptidasas/farmacología , Endopeptidasas/química , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/química
7.
ACS Appl Mater Interfaces ; 16(27): 35639-35650, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38916253

RESUMEN

Photonic crystal coatings with unique structural colors and self-cleaning properties have been providing an efficient way for substrate coloration. However, the enhancement of the robustness and durability of structural colored coatings to meet the requirements in diverse environments remains a challenging task. Here, to realize the application of photonic crystal films under various kinds of conditions, we present a poly(fluoroalkyl acrylate)-based colloidal photonic crystal (fCPC) coating. Fluorinated core-interlayer-shell (FCIS) colloidal particles of polystyrene (PS) core, poly(methyl methacrylate) (PMMA) interlayer, and poly(fluoroalkyl acrylate-ethyl acrylate-butyl acrylate) (P(FA-EA-BA)) shell copolymers have been first prepared by a stepwise emulsion polymerization. fCPCs with self-supporting property, reprocessing ability, friction resistance, as well as excellent wettability and liquid-repellent properties are successfully obtained via the bending-induced ordering technique (BIOT). When applied in antifouling applications, the fCPC film exhibits resistance against various oil and inorganic liquids. Furthermore, the fCPC coatings demonstrate their durability under outdoor conditions by maintaining stable color appearances during rainy and sunny conditions. Additionally, an electronic product adhered with the fCPC coatings is presented, which exhibits a surface that remains clean even after prolonged usage in comparison to the conventional CPC coating. Structural colored textiles with enhanced stability and functionalized liquid-repellent properties are achieved through a one-step process using FCIS particles. Therefore, the developed self-cleaning and comprehensive fCPC coatings capable of withstanding diverse conditions may open up new avenues for the advancement of structural coloration in decoration, vehicle, textile, and building.

8.
Front Endocrinol (Lausanne) ; 15: 1366219, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38887267

RESUMEN

Objective: The aim of this study was to develop a nomogram, using serum thymidine kinase 1 protein (STK1p) combined with ultrasonography parameters, to early predict central lymph node metastasis (CLNM) in patients with papillary thyroid carcinoma (PTC) pre-surgery. Methods: Patients with PTC pre-surgery in January 2021 to February 2023 were divided into three cohorts: the observation cohort (CLNM, n = 140), the control cohort (NCLNM, n = 128), and the external verification cohort (CLNM, n = 50; NCLNM, n = 50). STK1p was detected by an enzyme immunodot-blot chemiluminescence analyzer and clinical parameters were evaluated by ultrasonography. Results: A suitable risk threshold value for STK1p of 1.7 pmol/L was selected for predicting CLNM risk by receiver operating characteristic (ROC) curve analysis. Multivariate analysis identified the following six independent risk factors for CLNM: maximum tumor size >1 cm [odds ratio (OR) = 2.406, 95% confidence interval (CI) (1.279-4.526), p = 0.006]; capsule invasion [OR = 2.664, 95% CI (1.324-5.360), p = 0.006]; irregular margin [OR = 2.922; 95% CI (1.397-6.111), p = 0.004]; CLN flow signal [OR = 3.618, 95% CI (1.631-8.027), p = 0.002]; tumor-foci number ≥2 [OR = 4.064, 95% CI (2.102-7.859), p < 0.001]; and STK1p ≥1.7 pmol/L [OR = 7.514, 95% CI (3.852-14.660), p < 0.001]. The constructed nomogram showed that the area under the ROC curve for the main dataset was 0.867 and that for the validation dataset was 0.830, exhibiting effectivity, and was recalculated to a total score of approximately 383. Through monitoring the response post-surgery, all patients were assessed as tumor-free at 12 months post-surgery, which was significantly associated with a reduction in STK1p to disease-free levels. Conclusion: We demonstrate for the first time that a novel nomogram including STK1p combined with ultrasonography can assist in the clinical prevention of CLNM, by facilitating timely, individualized prophylactic CLNM dissection, thereby reducing the risk of secondary surgery and the probability of recurrence.


Asunto(s)
Metástasis Linfática , Nomogramas , Timidina Quinasa , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides , Ultrasonografía , Humanos , Masculino , Femenino , Timidina Quinasa/sangre , Persona de Mediana Edad , Adulto , Cáncer Papilar Tiroideo/sangre , Cáncer Papilar Tiroideo/cirugía , Cáncer Papilar Tiroideo/patología , Cáncer Papilar Tiroideo/diagnóstico por imagen , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/diagnóstico por imagen , Ultrasonografía/métodos , Biomarcadores de Tumor/sangre , Factores de Riesgo , Curva ROC , Pronóstico , Anciano , Adulto Joven , Ganglios Linfáticos/patología , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/cirugía
9.
BMC Anesthesiol ; 24(1): 212, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918712

RESUMEN

BACKGROUND: 3% chloroprocaine (CP) has been reported as the common local anesthetic used in pregnant women undergoing urgent cesarean delivery during labor analgesia period. However, 0.75% ropivacaine is considered a promising and effective alternative. Therefore, we conducted a randomized controlled trial to compare the effectiveness and safety of 0.75% ropivacaine with 3% chloroprocaine for extended epidural anesthesia in pregnant women. METHODS: We conducted a double-blind, randomized, controlled, single-center study from November 1, 2022, to April 30, 2023. We selected forty-five pregnant women undergoing urgent cesarean delivery during labor analgesia period and randomized them to receive either 0.75% ropivacaine or 3% chloroprocaine in a 1:1 ratio. The primary outcome was the time to loss of cold sensation at the T4 level. RESULTS: There was a significant difference between the two groups in the time to achieve loss of cold sensation (303, 95%CI 255 to 402 S vs. 372, 95%CI 297 to 630 S, p = 0.024). There was no significant difference the degree of motor block (p = 0.185) at the Th4 level. Fewer pregnant women required additional local anesthetics in the ropivacaine group compared to the chloroprocaine group (4.5% VS. 34.8%, p = 0.011). The ropivacaine group had lower intraoperative VAS scores (p = 0.023) and higher patient satisfaction scores (p = 0.040) than the chloroprocaine group. The incidence of intraoperative complications was similar between the two groups, and no serious complications were observed. CONCLUSIONS: Our study found that 0.75% ropivacaine was associated with less intraoperative pain treatment, higher patient satisfaction and reduced the onset time compared to 3% chloroprocaine in pregnant women undergoing urgent cesarean delivery during labor analgesia period. Therefore, 0.75% ropivacaine may be a suitable drug in pregnant women undergoing urgent cesarean delivery during labor analgesia period. CLINICAL TRIAL NUMBER AND REGISTRY URL: The registration number: ChiCTR2200065201; http://www.chictr.org.cn , Principal investigator: MEN, Date of registration: 31/10/2022.


Asunto(s)
Analgesia Obstétrica , Anestésicos Locales , Cesárea , Procaína , Ropivacaína , Humanos , Femenino , Ropivacaína/administración & dosificación , Embarazo , Método Doble Ciego , Cesárea/métodos , Anestésicos Locales/administración & dosificación , Adulto , Analgesia Obstétrica/métodos , Procaína/análogos & derivados , Procaína/administración & dosificación
10.
Angew Chem Int Ed Engl ; : e202403917, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38818640

RESUMEN

Although dearomative functionalizations enable the direct conversion of flat aromatics into precious three-dimensional architectures, the case for simple arenes remains largely underdeveloped owing to the high aromatic stabilization energy. We herein report a dearomative sequential addition of two nucleophiles to arene π-bonds through umpolung of chromium-arene complexes. This mode enables divergent dearomative carbonylation reactions of benzene derivatives by tolerating various nucleophiles in combination with alcohols or amines under CO-gas-free conditions, thus providing modular access to functionalized esters or amides. The tunable synthesis of 1,3- or 1,4-cyclohexadienes as well as the construction of carbon quaternary centers further highlight the versatility of this dearomatization. Diverse late-stage modifications and derivatizations towards synthetically challenging and bioactive molecules reveal the synthetic utility. A possible mechanism was proposed based on control experiments and intermediate tracking.

11.
Redox Biol ; 73: 103176, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38705094

RESUMEN

Excitotoxicity is a prevalent pathological event in neurodegenerative diseases. The involvement of ferroptosis in the pathogenesis of excitotoxicity remains elusive. Transcriptome analysis has revealed that cytoplasmic reduced nicotinamide adenine dinucleotide phosphate (NADPH) levels are associated with susceptibility to ferroptosis-inducing compounds. Here we show that exogenous NADPH, besides being reductant, interacts with N-myristoyltransferase 2 (NMT2) and upregulates the N-myristoylated ferroptosis suppressor protein 1 (FSP1). NADPH increases membrane-localized FSP1 and strengthens resistance to ferroptosis. Arg-291 of NMT2 is critical for the NADPH-NMT2-FSP1 axis-mediated suppression of ferroptosis. This study suggests that NMT2 plays a pivotal role by bridging NADPH levels and neuronal susceptibility to ferroptosis. We propose a mechanism by which the NADPH regulates N-myristoylation, which has important implications for ferroptosis and disease treatment.


Asunto(s)
Ferroptosis , NADP , Humanos , NADP/metabolismo , Animales , Aciltransferasas/metabolismo , Aciltransferasas/genética , Ratones , Procesamiento Proteico-Postraduccional
12.
PLoS One ; 19(4): e0300734, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38662660

RESUMEN

To encourage technological and industrial innovation, nations worldwide implement "re-industrialization" and "manufacturing return." This study investigates the relationship between GDP growth, expenditure on research and development, and medium- to high-tech as a percentage of manufactured exports on technological innovation in Pakistan. We evaluated long-run and short-run causal relationships using the ARDL, bound-F test, and ECM regression. The study found a positive relationship between GDP growth and technological innovation in the short and long run. In the short run, with a one-year lag, the analysis reveals a positive and statistically significant relationship between technological innovation, medium-high-tech exports, and GDP growth. In the long run, R&D is positive and significant, while economic growth and technological innovation are positive but not statistically significant. There is a 0.38 percent chance that exogenous shocks will eventually lead to equilibrium in the long run. Based on the findings of this study, it is recommended to allocate resources to research and development, promoting collaborative initiatives, ensuring intellectual property rights, and developing a skilled workforce.


Asunto(s)
Desarrollo Económico , Invenciones , Tecnología , Pakistán , Invenciones/economía , Tecnología/economía , Humanos , Desarrollo Industrial
13.
Insights Imaging ; 15(1): 101, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578423

RESUMEN

BACKGROUND: We aimed to explore the application value of various machine learning (ML) algorithms based on multicenter CT radiomics in identifying peripheral nerve invasion (PNI) of colorectal cancer (CRC). METHODS: A total of 268 patients with colorectal cancer who underwent CT examination in two hospitals from January 2016 to December 2022 were considered. Imaging and clinicopathological data were collected through the Picture Archiving and Communication System (PACS). The Feature Explorer software (FAE) was used to identify the peripheral nerve invasion of colorectal patients in center 1, and the best feature selection and classification channels were selected. Finally, the best feature selection and classifier pipeline were verified in center 2. RESULTS: The six-feature models using RFE feature selection and GP classifier had the highest AUC values, which were 0.610, 0.699, and 0.640, respectively. FAE generated a more concise model based on one feature (wavelet-HLL-glszm-LargeAreaHighGrayLevelEmphasis) and achieved AUC values of 0.614 and 0.663 on the validation and test sets, respectively, using the "one standard error" rule. Using ANOVA feature selection, the GP classifier had the best AUC value in a one-feature model, with AUC values of 0.611, 0.663, and 0.643 on the validation, internal test, and external test sets, respectively. Similarly, when using the "one standard error" rule, the model based on one feature (wave-let-HLL-glszm-LargeAreaHighGrayLevelEmphasis) achieved AUC values of 0.614 and 0.663 on the validation and test sets, respectively. CONCLUSIONS: Combining artificial intelligence and radiomics features is a promising approach for identifying peripheral nerve invasion in colorectal cancer. This innovative technique holds significant potential for clinical medicine, offering broader application prospects in the field. CRITICAL RELEVANCE STATEMENT: The multi-channel ML method based on CT radiomics has a simple operation process and can be used to assist in the clinical screening of patients with CRC accompanied by PNI. KEY POINTS: • Multi-channel ML in the identification of peripheral nerve invasion in CRC. • Multi-channel ML method based on CT-radiomics can detect the PNI of CRC. • Early preoperative identification of PNI in CRC is helpful to improve the formulation of treatment strategies and the prognosis of patients.

14.
World J Gastroenterol ; 30(11): 1524-1532, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38617452

RESUMEN

Autophagy is a cellular catabolic process characterized by the formation of double-membrane autophagosomes. Transmission electron microscopy is the most rigorous method to clearly visualize autophagic engulfment and degradation. A large number of studies have shown that autophagy is closely related to the digestion, secretion, and regeneration of gastrointestinal (GI) cells. However, the role of autophagy in GI diseases remains controversial. This article focuses on the morphological and biochemical characteristics of autophagy in GI diseases, in order to provide new ideas for their diagnosis and treatment.


Asunto(s)
Enfermedades Gastrointestinales , Humanos , Autofagia , Microscopía Electrónica de Transmisión
15.
Ecotoxicol Environ Saf ; 276: 116340, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38636261

RESUMEN

Exposure to pesticides induces oxidative stress and deleterious effects on various tissues in non-target organisms. Numerous models investigating pesticide exposure have demonstrated metabolic disturbances such as imbalances in amino acid levels within the organism. One potentially effective strategy to mitigate pesticide toxicity involves dietary intervention by supplementing exogenous amino acids and their derivates to augment the body's antioxidant capacity and mitigate pesticide-induced oxidative harm, whose mechanism including bolstering glutathione synthesis, regulating arginine-NO metabolism, mitochondria-related oxidative stress, and the open of ion channels, as well as enhancing intestinal microecology. Enhancing glutathione synthesis through supplementation of substrates N-acetylcysteine and glycine is regarded as a potent mechanism to achieve this. Selection of appropriate amino acids or their derivates for supplementation, and determining an appropriate dosage, are of the utmost importance for effective mitigation of pesticide-induced oxidative harm. More experimentation is required that involves large population samples to validate the efficacy of dietary intervention strategies, as well as to determine the effects of amino acids and their derivates on long-term and low-dose pesticide exposure. This review provides insights to guide future research aimed at preventing and alleviating pesticide toxicity through dietary intervention of amino acids and their derivates.


Asunto(s)
Aminoácidos , Estrés Oxidativo , Plaguicidas , Plaguicidas/toxicidad , Estrés Oxidativo/efectos de los fármacos , Animales , Antioxidantes/farmacología , Glutatión/metabolismo , Suplementos Dietéticos , Humanos
16.
CNS Neurosci Ther ; 30(4): e14713, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38615362

RESUMEN

AIMS: We aimed to evaluate the potential of a novel selective α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPAR) potentiator, LT-102, in treating cognitive impairments associated with schizophrenia (CIAS) and elucidating its mechanism of action. METHODS: The activity of LT-102 was examined by Ca2+ influx assays and patch-clamp in rat primary hippocampal neurons. The structure of the complex was determined by X-ray crystallography. The selectivity of LT-102 was evaluated by hERG tail current recording and kinase-inhibition assays. The electrophysiological characterization of LT-102 was characterized by patch-clamp recording in mouse hippocampal slices. The expression and phosphorylation levels of proteins were examined by Western blotting. Cognitive function was assessed using the Morris water maze and novel object recognition tests. RESULTS: LT-102 is a novel and selective AMPAR potentiator with little agonistic effect, which binds to the allosteric site formed by the intradimer interface of AMPAR's GluA2 subunit. Treatment with LT-102 facilitated long-term potentiation in mouse hippocampal slices and reversed cognitive deficits in a phencyclidine-induced mouse model. Additionally, LT-102 treatment increased the protein level of brain-derived neurotrophic factor and the phosphorylation of GluA1 in primary neurons and hippocampal tissues. CONCLUSION: We conclude that LT-102 ameliorates cognitive impairments in a phencyclidine-induced model of schizophrenia by enhancing synaptic function, which could make it a potential therapeutic candidate for CIAS.


Asunto(s)
Disfunción Cognitiva , Propionatos , Esquizofrenia , Animales , Ratones , Ratas , Fenciclidina , Esquizofrenia/complicaciones , Esquizofrenia/tratamiento farmacológico , Disfunción Cognitiva/tratamiento farmacológico , Isoxazoles
17.
Phys Med Biol ; 69(8)2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38484392

RESUMEN

Objective.Monolithic crystal detectors are increasingly being applied in positron emission tomography (PET) devices owing to their excellent depth-of-interaction (DOI) resolution capabilities and high detection efficiency. In this study, we constructed and evaluated a dual-ended readout monolithic crystal detector based on a multiplexing method.Approach.We employed two 12 × 12 silicon photomultiplier (SiPM) arrays for readout, and the signals from the 12 × 12 array were merged into 12 X and 12 Y channels using channel multiplexing. In 2D reconstruction, three methods based on the centre of gravity (COG) were compared, and the concept of thresholds was introduced. Furthermore, a light convolutional neural network (CNN) was employed for testing. To enhance depth localization resolution, we proposed a method by utilizing the mutual information from both ends of the SiPMs. The source width and collimation effect were simulated using GEANT4, and the intrinsic spatial resolution was separated from the measured values.Main results.At an operational voltage of 29 V for the SiPM, an energy resolution of approximately 12.5 % was achieved. By subtracting a 0.8 % threshold from the total energy in every channel, a 2D spatial resolution of approximately 0.90 mm full width at half maximum (FWHM) can be obtained. Furthermore, a higher level of resolution, approximately 0.80 mm FWHM, was achieved using a CNN, with some alleviation of edge effects. With the proposed DOI method, a significant 1.36 mm FWHM average DOI resolution can be achieved. Additionally, it was found that polishing and black coating on the crystal surface yielded smaller edge effects compared to a rough surface with a black coating.Significance.The introduction of a threshold in COG method and a dual-ended readout scheme can lead to excellent spatial resolution for monolithic crystal detectors, which can help to develop PET systems with both high sensitivity and high spatial resolution.


Asunto(s)
Redes Neurales de la Computación , Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones/métodos , Fotones , Gravitación
18.
J Am Chem Soc ; 146(13): 9444-9454, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38513075

RESUMEN

The 3d transition metal-catalyzed enantioconvergent radical cross-coupling provides a powerful tool for chiral molecule synthesis. In the classic mechanism, the bond formation relies on the interaction between nucleophile-sequestered metal complexes and radicals, limiting the nucleophile scope to sterically uncongested ones. The coupling of sterically congested nucleophiles poses a significant challenge due to difficulties in transmetalation, restricting the reaction generality. Here, we describe a probable outer-sphere nucleophilic attack mechanism that circumvents the challenging transmetalation associated with sterically congested nucleophiles. This strategy enables a general copper-catalyzed enantioconvergent radical N-alkylation of aromatic amines with secondary/tertiary alkyl halides and exhibits catalyst-controlled stereoselectivity. It accommodates diverse aromatic amines, especially bulky secondary and primary ones to deliver value-added chiral amines (>110 examples). It is expected to inspire the coupling of more nucleophiles, particularly challenging sterically congested ones, and accelerate reaction generality.

19.
J Ethnopharmacol ; 327: 118020, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38458341

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Polygala tenuifilia Willd (Polygalaceae), a traditional Chinese medicine, has been used for a long time to treat various illnesses with serious adverse reactions. Glycyrrhizae radix et rhizoma processing is generally used to reduce the adverse reactions. AIM OF THE STUDY: The aim of this study was to validate the irritation caused by raw Polygalaceae (RPA), to investigate whether processed Polygalaceae (PGA) was less irritating, and to screen and validate irritant properties of virgaureagenin G (polygala acid, PA), 3,6'-disinapoylsucrose (DSS), Tenuifolia (TEN) and polygalaxanthone III (POL), which had pharmacologically active in Polygalaceae. Zebrafish model, Draize test and High-Performance Liquid Chromatography (HPLC) were utilized to achieve the aim. MATERIALS AND METHODS: Scanning Electron Microscopy (SEM) and optical microscope were used to determine the presence of calcium oxalate needle crystal in RPA and PGA. Zebrafish egg spinning changes and zebrafish embryo behavior were used for irritation validation, irritation comparison and irritant screening. For additional evidence, the Draize test, HE staining of rabbit eyes and ELISA kit were used. Finally, changes in the composition of RPA and PGA were investigated using HPLC. RESULTS: SEM and optical microscopy revealed no calcium oxalate needle crystals in Polygalaceae. RPA, PGA, PA and DSS were able to accelerate the spinning of zebrafish eggs and the movement of embryos, while TEN and POL were not. RPA, PGA, DSS and PA may cause rabbit eyes to become hyperemic and swollen, resulting in damage to the iris, cornea and conjunctiva and increased levels of interleukin-6 (IL-6) and interleukin-10 (IL-10). Comparatively, the effects caused by PGA were less severe than those caused by RPA. In addition, compared to RPA, PGA had lower levels of DSS and PA. CONCLUSIONS: RPA, PGA, DSS, and PA were irritating. However, processing and curing could reduce the irritation by reducing the levels of DSS and PA. DSS and PA could be two potential irritants of Polygalaceae.


Asunto(s)
Medicamentos Herbarios Chinos , Glycyrrhiza , Polygala , Animales , Conejos , Pez Cebra , Irritantes , Medicamentos Herbarios Chinos/química , Raíces de Plantas/química , Polygala/química , Oxalato de Calcio
20.
ACS Appl Mater Interfaces ; 16(10): 12647-12660, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38437590

RESUMEN

Three new heteroleptic Ru complexes, CYC-B22, CYC-B23C, and CYC-B23T, were prepared as sensitizers for coadsorbent-free, panchromatic, and efficient dye-sensitized solar cells. They are simultaneously functionalized with highly conjugated anchoring and ancillary ligands to explore the electronic and steric effects on their photovoltaic characteristics. The coadsorbent-free device based on CYC-B22 achieved the best power conversion efficiency (PCE) of 8.63% and a panchromatic response extending to 850 nm. The two stereoisomers, CYC-B23C and CYC-B23T coordinated with an unsymmetrical anchoring ligand, display similar absorption properties and the same driving forces for electron injection as well as dye regeneration. Nevertheless, the devices show not only the remarkably distinct PCE (6.64% vs 8.38%) but also discernible stability. The molecular simulation for the two stereoisomers adsorbed on TiO2 clarifies the distinguishable distances (16.9 Å vs 19.0 Å) between the sulfur atoms in the NCS ligands and the surface of the TiO2, dominating the charge recombination dynamics and iodine binding and therefore the PCE and stability of the devices. This study on the steric effects caused by the highly conjugated and unsymmetrical anchoring ligand on the adsorption geometry and photovoltaic performance of the dyes paves a new way for advancing the molecular design of polypyridyl metal complex sensitizers.

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