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1.
EMBO J ; 43(6): 931-955, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38360997

RESUMEN

The Von Hippel-Lindau (VHL) protein, which is frequently mutated in clear-cell renal cell carcinoma (ccRCC), is a master regulator of hypoxia-inducible factor (HIF) that is involved in oxidative stresses. However, whether VHL possesses HIF-independent tumor-suppressing activity remains largely unclear. Here, we demonstrate that VHL suppresses nutrient stress-induced autophagy, and its deficiency in sporadic ccRCC specimens is linked to substantially elevated levels of autophagy and correlates with poorer patient prognosis. Mechanistically, VHL directly binds to the autophagy regulator Beclin1, after its PHD1-mediated hydroxylation on Pro54. This binding inhibits the association of Beclin1-VPS34 complexes with ATG14L, thereby inhibiting autophagy initiation in response to nutrient deficiency. Expression of non-hydroxylatable Beclin1 P54A abrogates VHL-mediated autophagy inhibition and significantly reduces the tumor-suppressing effect of VHL. In addition, Beclin1 P54-OH levels are inversely correlated with autophagy levels in wild-type VHL-expressing human ccRCC specimens, and with poor patient prognosis. Furthermore, combined treatment of VHL-deficient mouse tumors with autophagy inhibitors and HIF2α inhibitors suppresses tumor growth. These findings reveal an unexpected mechanism by which VHL suppresses tumor growth, and suggest a potential treatment for ccRCC through combined inhibition of both autophagy and HIF2α.


Asunto(s)
Beclina-1 , Carcinoma de Células Renales , Neoplasias Renales , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau , Animales , Humanos , Ratones , Autofagia , Beclina-1/genética , Beclina-1/metabolismo , Carcinoma de Células Renales/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Hidroxilación , Neoplasias Renales/metabolismo , Procolágeno-Prolina Dioxigenasa/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo
2.
Plant Physiol ; 195(3): 1925-1940, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38427921

RESUMEN

Leaf senescence is a vital aspect of plant physiology and stress responses and is induced by endogenous factors and environmental cues. The plant-specific NAC (NAM, ATAF1/2, CUC2) transcription factor family influences growth, development, and stress responses in Arabidopsis (Arabidopsis thaliana) and other species. However, the roles of NACs in tobacco (Nicotiana tabacum) leaf senescence are still unclear. Here, we report that NtNAC56 regulates leaf senescence in tobacco. Transgenic plants overexpressing NtNAC56 (NtNAC56-OE) showed induction of senescence-related genes and exhibited early senescence and lower chlorophyll content compared to wild-type (WT) plants and the Ntnac56-19 mutant. In addition, root development and seed germination were inhibited in the NtNAC56-OE lines. Transmission electron microscopy observations accompanied by physiological and biochemical assays revealed that NtNAC56 overexpression triggers chloroplast degradation and reactive oxygen species accumulation in tobacco leaves. Transcriptome analysis demonstrated that NtNAC56 activates leaf senescence-related genes and jasmonic acid (JA) biosynthesis pathway genes. In addition, the JA content of NtNAC56-OE plants was higher than in WT plants, and JA treatment induced NtNAC56 expression. We performed DNA affinity purification sequencing to identify direct targets of NtNAC56, among which we focused on LIPOXYGENASE 5 (NtLOX5), a key gene in JA biosynthesis. A dual-luciferase reporter assay and a yeast one-hybrid assay confirmed that NtNAC56 directly binds to the TTTCTT motif in the NtLOX5 promoter. Our results reveal a mechanism whereby NtNAC56 regulates JA-induced leaf senescence in tobacco and provide a strategy for genetically manipulating leaf senescence and plant growth.


Asunto(s)
Ciclopentanos , Regulación de la Expresión Génica de las Plantas , Nicotiana , Oxilipinas , Hojas de la Planta , Proteínas de Plantas , Senescencia de la Planta , Plantas Modificadas Genéticamente , Factores de Transcripción , Nicotiana/genética , Nicotiana/fisiología , Nicotiana/efectos de los fármacos , Nicotiana/crecimiento & desarrollo , Oxilipinas/metabolismo , Oxilipinas/farmacología , Ciclopentanos/metabolismo , Ciclopentanos/farmacología , Hojas de la Planta/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/fisiología , Senescencia de la Planta/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Especies Reactivas de Oxígeno/metabolismo , Clorofila/metabolismo , Cloroplastos/metabolismo , Cloroplastos/ultraestructura , Regiones Promotoras Genéticas/genética
3.
FASEB J ; 38(5): e23519, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38457249

RESUMEN

ARL3 is essential for cilia development, and mutations in ARL3 are closely associated with ciliopathies. In a previous study, we observed distinct phenotypes of retinal dystrophy in patients with heterozygous ARL3T31A and compound heterozygous ARL3T31A/C118F mutations, indicating that different mutation types may exert diverse effects on their functions. Here, we generated transformed immortal fibroblast cells from patients carrying heterozygous ARL3T31A and compound heterozygous ARL3T31A/C118F mutations, and systematically evaluated their cilia morphology and function, which were further validated in ARPE-19 cells. Results showed that both ARL3T31A and ARL3T31A/C118F mutations led to a decrease in cilium formation. The ARL3T31A/C118F mutations caused significantly elongated cilia and impaired retrograde transport, whereas the ARL3T31A mutation did not induce significant changes in fibroblasts. RNA-sequencing results indicated that compared to ARL3T31A , ARL3T31A/C118F fibroblasts exhibited a higher enrichment of biological processes related to neuron projection development, tissue morphogenesis, and extracellular matrix (ECM) organization, with noticeable alterations in pathways such as ECM-receptor interaction, focal adhesion, and TGF-ß signaling. Similar changes were observed in the proteomic results in ARPE-19 cells. Core regulated genes including IQUB, UNC13D, RAB3IP, and GRIP1 were specifically downregulated in the ARL3T31A/C118F group, and expressions of IQUB, NPM2, and SLC38A4 were further validated. Additionally, IQUB showed a rescuing effect on the overlong cilia observed in ARL3T31A/C118F fibroblasts. Our results not only enhance our understanding of ARL3-related diseases but also provide new insights into the analysis of heterozygous and compound heterozygous mutations in genetics.


Asunto(s)
Cilios , Proteómica , Humanos , Cilios/genética , Cilios/metabolismo , Transporte de Proteínas , Factores de Ribosilacion-ADP/genética , Factores de Ribosilacion-ADP/metabolismo , Mutación , Fibroblastos/metabolismo , Proteínas de la Membrana/metabolismo
4.
Stroke ; 55(4): 856-865, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38362756

RESUMEN

BACKGROUND: The present study aimed to evaluate the efficacy and safety of intravenous tirofiban versus alteplase before endovascular treatment (EVT) in acute ischemic stroke patients with intracranial large vessel occlusion. METHODS: This was a post hoc analysis using data from 2 multicenter, randomized trials: the DEVT trial (Direct Endovascular Treatment for Large Vessel Occlusion Stroke) from May 2018 to May 2020 and the RESCUE BT trial (Intravenous Tirofiban Before Endovascular Thrombectomy for Acute Ischemic Stroke) from October 2018 to October 2021. Patients with acute intracranial large vessel occlusion within 4.5 hours from last known well were dichotomized into 2 groups: tirofiban plus EVT versus alteplase bridging with EVT. The primary outcome was functional independence (modified Rankin Scale score of 0-2) at 90 days. Safety outcomes included symptomatic intracranial hemorrhage and 3-month mortality. Multivariable logistic regression (adjusting for baseline systolic blood pressure, occlusion site, onset-to-puncture time, anesthesia, and first choice of EVT) and propensity score overlap weighting (balance in demographic covariates, stroke characteristics, and initial management between groups) were performed. RESULTS: One-hundred and eighteen alteplase-treated patients in the DEVT trial and 98 tirofiban-treated patients in the RESCUE BT trial were included (median age, 70 years; 115 [53.2%] men). The rate of functional independence was 60.2% in the tirofiban group compared with 46.6% in the alteplase group (adjusted odds ratio, 1.25 [95% CI, 0.60-2.63]). Compared with alteplase, tirofiban was not associated with increased risk of symptomatic intracranial hemorrhage (6.8% versus 9.2%; P=0.51) and mortality (17.8% versus 19.4%; P=0.76). The propensity score overlap weighting analyses showed consistent outcomes. CONCLUSIONS: Among patients with intracranial large vessel occlusion within 4.5 hours of onset, tirofiban plus EVT was comparable to alteplase bridging with EVT regarding the efficacy and safety outcomes. These findings should be interpreted as preliminary and require confirmation in a randomized trial. REGISTRATION: URL: https://www.chictr.org.cn; Unique identifiers: ChiCTR-IOR-17013568 and ChiCTR-INR-17014167.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Masculino , Humanos , Anciano , Femenino , Activador de Tejido Plasminógeno/uso terapéutico , Tirofibán/uso terapéutico , Fibrinolíticos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/cirugía , Terapia Trombolítica/efectos adversos , Resultado del Tratamiento , Procedimientos Endovasculares/efectos adversos , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/cirugía , Trombectomía/efectos adversos , Hemorragias Intracraneales/etiología , Hemorragias Intracraneales/inducido químicamente , Estudios Multicéntricos como Asunto
5.
J Am Chem Soc ; 146(31): 21968-21976, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39052048

RESUMEN

Electrified synthesis of high-value organonitrogen chemicals from low-cost carbon- and nitrogen-based feedstocks offers an economically and environmentally appealing alternative to traditional thermocatalytic methods. However, the intricate electrochemical reactions at electrode surfaces pose significant challenges in controlling selectivity and activity, especially for producing complex substances such as N,N-dimethylformamide (DMF). Herein, we tackle this challenge by developing relay catalysis for efficient DMF production using a composite WO2-NiOOH/Ni catalyst with two distinctive active sites. Specifically, WO2 selectively promotes dimethylamine (DMA) electrooxidation to produce strongly surface-bound (CH3)2N*, while nearby NiOOH facilitates methanol electrooxidation to yield more weakly bound *CHO. The disparity in binding energetics of the key C- and N-intermediates expedites C-N coupling at the WO2-NiOOH interface. In situ infrared spectroscopy with isotope-labeling experiments, quasi-in situ electron paramagnetic resonance trapping experiments, and electrochemical operating experiments revealed the C-N coupling mechanism and enhanced DMF-synthesis selectivity and activity. In situ X-ray absorption spectroscopy (XAS) and postreaction transmission electron microscopy (TEM) studies verified the stability of WO2-NiOOH/Ni during extended electrochemical operation. A Faradaic efficiency of ∼50% and a production rate of 438 µmol cm-2 h-1 were achieved at an industrially relevant current density of 100 mA cm-2 over an 80 h DMF production period. This study introduces a new paradigm for developing electrothermo relay catalysis for the sustainable and efficient synthesis of valuable organic chemicals with industrial potential.

6.
Br J Haematol ; 204(5): 1780-1789, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38369805

RESUMEN

Chimeric antigen receptor T-cell (CAR-T) therapy targeting B-cell maturation antigen (BCMA) has shown profound efficacy and manageable toxicity in patients with relapsed/refractory multiple myeloma (RRMM). However, determining the best course of treatment for post-CAR-T therapy relapse remains a significant challenge. We conducted a retrospective analysis of patients from the phase I LEGEND-2 study (NCT03090659) enrolled at the Xi'an site, analysing the first salvage line of therapy and outcomes in patients with RRMM who progressed after receiving LCAR-B38M CAR-T therapy. Of 45 eligible patients, 34 (76%) had progressive disease (PD). Overall response rate (ORR) to salvage treatment was 50.0%. Median progression-free survival (PFS) after starting salvage treatment was 16.3 months. Median PFS of patients receiving proteasome inhibitor (PI)-based combination therapy was longer (28.2 months) than that of patients receiving a second BCMA CAR-T (including LCAR-B38M; 3.9 months, p = 0.0022) or chemotherapy (1.67 months, p = 0.0001). All patients with extramedullary disease at baseline (n = 11) progressed after CAR-T therapy; ORR to salvage therapy was 25.0% and median PFS was 9.7 months. In conclusion, salvage therapy in patients with PD after receiving LCAR-B38M CAR-T cells produced moderate efficacy, with better outcomes for PI-based salvage regimens.


Asunto(s)
Antígeno de Maduración de Linfocitos B , Inmunoterapia Adoptiva , Mieloma Múltiple , Terapia Recuperativa , Humanos , Mieloma Múltiple/terapia , Mieloma Múltiple/mortalidad , Terapia Recuperativa/métodos , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Inmunoterapia Adoptiva/efectos adversos , Inmunoterapia Adoptiva/métodos , Anciano , Adulto , Resultado del Tratamiento
7.
Neuroepidemiology ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39134004

RESUMEN

Objective Complications or serious adverse events (SAEs) are common in the treatment of patients with large vessel occlusion stroke. There has been limited study of the impact of SAEs for patients after endovascular thrombectomy (EVT). The goal of this study was to characterize the rates and clinical impact of SAEs following EVT. Methods A post-hoc analysis was performed using pooled databases of the 'DEVT' and 'RESCUE BT' trials. SAEs were designated as symptomatic intracranial hemorrhage, brain herniation or craniectomy, respiratory failure, circulatory failure, pneumonia, deep venous thrombosis, and systemic bleeding. The primary endpoint was functional independence (modified Rankin Scale score 0-2 within 90 days). Logistic regression analysis was used to determine the predictors and associations between SAEs and outcomes. Results Of 1182 enrolled patients, 402 (34%) had a procedural complication, 745 (63%) had 1404 SAEs occurrences with 4.65% in-hospital mortality. The three most frequent SAEs were pneumonia (620, 52.5%), systemic bleeding (174, 14.7%) and respiratory failure (173, 14.6%). Pneumonia, systemic bleeding or deep venous thrombosis were less life-threatening. Patients with advanced age (adjusted odds ratio, 1.28 [95% confidence interval, 1.14-1.43]), higher NIHSS (1.09 [1.06-1.11]), occlusion site (middle cerebral artery-M1 vs. intracranial cerebral artery [ICA]: 0.75 [0.53-1.04]; M2 vs. ICA: 1.30 [0.80-2.12]), longer procedure time (1.01 [1.00-1.01]) and unsuccessful vessel recanalization (1.79 [1.06-2.94]) were more likely to experience SAEs. Compared with no SAE, patients with SAEs had lower odds of functional independence (0.46 [0.40-0.54]). Conclusions Overall, SAEs diagnosed following thrombectomy in patients with stroke were common (more than 60%) and associated with functional dependence. Patients with advanced age, higher NIHSS, longer procedure time and failed recanalization were more likely to experience SAEs. There was no statistical difference in the risk of SAEs among patient with M1 and M2 occluded compared with those ICA occluded. An understanding of the prevalence and predictors of SAEs could alert clinicians to the estimated risk of an SAE for a patient after EVT.

8.
BMC Public Health ; 24(1): 1194, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38685020

RESUMEN

BACKGROUND: TikTok is emerging as a vital platform for health information dissemination. Despite myopia being a global public health issue, the high-quality myopia information shared by health educators often fails to go viral. It is imperative to analyze the factors influencing video quality and popularity, especially from diverse perspectives of researchers, health educators, and audiences. METHODS: TikTok myopia-related videos were retrieved using TikTok's default comprehensive search (DCS) and most liked search (MLS) strategies. Venn diagrams were employed to illustrate the relationships and commonalities between the two strategies across four sample sizes (top 200, 150, 100, and 50). Video metadata, including details such as creator information, production properties, upload time, video duration, and viewer engagement, were collected. Video quality was assessed using the DISCERN tool. Video content covering six aspects of myopia were evaluated. The impact of search strategies, video sample sizes, production properties, and myopia content on video quality and audience engagement was analyzed through single-factor or multi-factor analysis. RESULTS: DCS and MLS retrieval strategies, as well as varying sample sizes, resulted in differences in audience engagement for myopia videos (P < 0.039), while The DISCERN quality scores remained comparable (P > 0.221). Videos published by healthcare professionals (HCPs) and non-profit organizations (NPOs) were associated with high-quality (P ≤ 0.014) but comparatively lower popularity (P < 0.033). Videos that reported contents of risk factors, management, and outcomes showed high popularity (P < 0.018), while longer video duration (> 60s) exhibited the opposite trend (P < 0.032). Content on myopia evaluation (P ≤ 0.001) and management (P ≤ 0.022) and video duration were positively correlated with higher DISCERN quality. CONCLUSION: Videos created by HCPs and NPOs deserve greater attention. Rather than pursuing entertaining effects, professional educators should emphasize producing concise, and high-quality myopia content that readily resonates with the audience and has the potential to go viral on the platform.


Asunto(s)
Miopía , Grabación en Video , Humanos , Miopía/terapia , Difusión de la Información/métodos
9.
JAMA ; 331(10): 840-849, 2024 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-38329440

RESUMEN

Importance: It is uncertain whether intravenous methylprednisolone improves outcomes for patients with acute ischemic stroke due to large-vessel occlusion (LVO) undergoing endovascular thrombectomy. Objective: To assess the efficacy and adverse events of adjunctive intravenous low-dose methylprednisolone to endovascular thrombectomy for acute ischemic stroke secondary to LVO. Design, Setting, and Participants: This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 82 hospitals in China, enrolling 1680 patients with stroke and proximal intracranial LVO presenting within 24 hours of time last known to be well. Recruitment took place between February 9, 2022, and June 30, 2023, with a final follow-up on September 30, 2023. Interventions: Eligible patients were randomly assigned to intravenous methylprednisolone (n = 839) at 2 mg/kg/d or placebo (n = 841) for 3 days adjunctive to endovascular thrombectomy. Main Outcomes and Measures: The primary efficacy outcome was disability level at 90 days as measured by the overall distribution of the modified Rankin Scale scores (range, 0 [no symptoms] to 6 [death]). The primary safety outcomes included mortality at 90 days and the incidence of symptomatic intracranial hemorrhage within 48 hours. Results: Among 1680 patients randomized (median age, 69 years; 727 female [43.3%]), 1673 (99.6%) completed the trial. The median 90-day modified Rankin Scale score was 3 (IQR, 1-5) in the methylprednisolone group vs 3 (IQR, 1-6) in the placebo group (adjusted generalized odds ratio for a lower level of disability, 1.10 [95% CI, 0.96-1.25]; P = .17). In the methylprednisolone group, there was a lower mortality rate (23.2% vs 28.5%; adjusted risk ratio, 0.84 [95% CI, 0.71-0.98]; P = .03) and a lower rate of symptomatic intracranial hemorrhage (8.6% vs 11.7%; adjusted risk ratio, 0.74 [95% CI, 0.55-0.99]; P = .04) compared with placebo. Conclusions and Relevance: Among patients with acute ischemic stroke due to LVO undergoing endovascular thrombectomy, adjunctive methylprednisolone added to endovascular thrombectomy did not significantly improve the degree of overall disability. Trial Registration: ChiCTR.org.cn Identifier: ChiCTR2100051729.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Femenino , Humanos , Anciano , Método Doble Ciego , Trombectomía/efectos adversos , Hemorragias Intracraneales , Metilprednisolona/efectos adversos
10.
Int J Mol Sci ; 25(5)2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38474064

RESUMEN

Our previous study has reported that metastasis-associated protein 2 (MTA2) plays essential roles in tumorigenesis and aggressiveness of gastric cancer (GC). However, the underlying molecular mechanisms of MTA2-mediated GC and its upstream regulation mechanism remain elusive. In this study, we identified a novel circular RNA (circRNA) generated from the MTA2 gene (circMTA2) as a crucial regulator in GC progression. CircMTA2 was highly expressed in GC tissues and cell lines, and circMTA2 promoted the proliferation, invasion, and metastasis of GC cells both in vitro and in vivo. Mechanistically, circMTA2 interacted with ubiquitin carboxyl-terminal hydrolase L3 (UCHL3) to restrain MTA2 ubiquitination and stabilize MTA2 protein expression, thereby facilitating tumor progression. Moreover, circMTA2 was mainly encapsulated and transported by exosomes to promote GC cell progression. Taken together, these findings uncover that circMTA2 suppresses MTA2 degradation by interacting with UCHL3, thereby promoting GC progression. In conclusion, we identified a cancer-promoting axis (circMTA2/UCHL3/MTA2) in GC progression, which paves the way for us to design and synthesize targeted inhibitors as well as combination therapies.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patología , Proteínas Represoras/genética , Línea Celular Tumoral , Histona Desacetilasas/metabolismo , Proteolisis , Regulación Neoplásica de la Expresión Génica , Proliferación Celular/genética , Ubiquitina Tiolesterasa/metabolismo
11.
World J Microbiol Biotechnol ; 40(6): 181, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38668833

RESUMEN

In view of the extensive potential applications of chitinase (ChiA) in various fields such as agriculture, environmental protection, medicine, and biotechnology, the development of a high-yielding strain capable of producing chitinase with enhanced activity holds significant importance. The objective of this study was to utilize the extracellular chitinase from Bacillus thuringiensis as the target, and Bacillus licheniformis as the expression host to achieve heterologous expression of ChiA with enhanced activity. Initially, through structural analysis and molecular dynamics simulation, we identified key amino acids to improve the enzymatic performance of chitinase, and the specific activity of chitinase mutant D116N/E118N was 48% higher than that of the natural enzyme, with concomitant enhancements in thermostability and pH stability. Subsequently, the expression elements of ChiA(D116N/E118N) were screened and modified in Bacillus licheniformis, resulting in extracellular ChiA activity reached 89.31 U/mL. Further efforts involved the successful knockout of extracellular protease genes aprE, bprA and epr, along with the gene clusters involved in the synthesis of by-products such as bacitracin and lichenin from Bacillus licheniformis. This led to the development of a recombinant strain, DW2△abelA, which exhibited a remarkable improvement in chitinase activity, reaching 145.56 U/mL. To further improve chitinase activity, a chitinase expression frame was integrated into the genome of DW2△abelA, resulting in a significant increas to 180.26 U/mL. Optimization of fermentation conditions and medium components further boosted shake flask enzyme activity shake flask enzyme activity, achieving 200.28 U/mL, while scale-up fermentation experiments yielded an impressive enzyme activity of 338.79 U/mL. Through host genetic modification, expression optimization and fermentation optimization, a high-yielding ChiA strain was successfully constructed, which will provide a solid foundation for the extracellular production of ChiA.


Asunto(s)
Bacillus licheniformis , Proteínas Bacterianas , Quitinasas , Bacillus licheniformis/genética , Bacillus licheniformis/enzimología , Bacillus thuringiensis/genética , Bacillus thuringiensis/enzimología , Bacitracina , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Quitinasas/biosíntesis , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Simulación de Dinámica Molecular , Familia de Multigenes , Proteínas Recombinantes/biosíntesis , Temperatura
13.
JMIR Med Educ ; 10: e52784, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39140269

RESUMEN

Background: With the increasing application of large language models like ChatGPT in various industries, its potential in the medical domain, especially in standardized examinations, has become a focal point of research. Objective: The aim of this study is to assess the clinical performance of ChatGPT, focusing on its accuracy and reliability in the Chinese National Medical Licensing Examination (CNMLE). Methods: The CNMLE 2022 question set, consisting of 500 single-answer multiple choices questions, were reclassified into 15 medical subspecialties. Each question was tested 8 to 12 times in Chinese on the OpenAI platform from April 24 to May 15, 2023. Three key factors were considered: the version of GPT-3.5 and 4.0, the prompt's designation of system roles tailored to medical subspecialties, and repetition for coherence. A passing accuracy threshold was established as 60%. The χ2 tests and κ values were employed to evaluate the model's accuracy and consistency. Results: GPT-4.0 achieved a passing accuracy of 72.7%, which was significantly higher than that of GPT-3.5 (54%; P<.001). The variability rate of repeated responses from GPT-4.0 was lower than that of GPT-3.5 (9% vs 19.5%; P<.001). However, both models showed relatively good response coherence, with κ values of 0.778 and 0.610, respectively. System roles numerically increased accuracy for both GPT-4.0 (0.3%-3.7%) and GPT-3.5 (1.3%-4.5%), and reduced variability by 1.7% and 1.8%, respectively (P>.05). In subgroup analysis, ChatGPT achieved comparable accuracy among different question types (P>.05). GPT-4.0 surpassed the accuracy threshold in 14 of 15 subspecialties, while GPT-3.5 did so in 7 of 15 on the first response. Conclusions: GPT-4.0 passed the CNMLE and outperformed GPT-3.5 in key areas such as accuracy, consistency, and medical subspecialty expertise. Adding a system role insignificantly enhanced the model's reliability and answer coherence. GPT-4.0 showed promising potential in medical education and clinical practice, meriting further study.


Asunto(s)
Evaluación Educacional , Licencia Médica , Humanos , China , Evaluación Educacional/métodos , Evaluación Educacional/normas , Reproducibilidad de los Resultados , Competencia Clínica/normas
14.
Biomed Opt Express ; 15(4): 2708-2718, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38633062

RESUMEN

The two-photon all-optical physiology system has attracted great interest in deciphering neuronal circuits in vivo, benefiting from its advantages in recording and modulating neuronal activities at single neuron resolutions. However, the interference, or crosstalk, between the imaging and photostimulation beams introduces a significant challenge and may impede the future application of voltage indicators in two-photon all-optical physiology system. Here, we propose the time multiplexed excitation method to distinguish signals from neuronal activities and crosstalks from photostimulation. In our system, the laser pulses of the imaging beam and photostimulation beam are synchronized, and a time delay is introduced into these pulses to separate the fluorescence signal generated by these two beams. We demonstrate the efficacy of our system in eliminating crosstalk signals from photostimulation and evaluate its influence on both genetically encoded calcium indicators (GECIs) and genetically encoded voltage indicators (GEVIs) through in vivo experiments.

15.
ACS Appl Mater Interfaces ; 16(8): 10138-10147, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38364211

RESUMEN

Enhancing the reaction selectivity for multicarbon products (C2+) is an important goal for the electrochemical CO(2) reduction (ECO(2)R) process. Cuprous compounds have demonstrated promising C2+ selectivity in the ECO(2)R process, but further investigation is necessary to thoroughly elucidate their catalytic behavior toward C2+ oxygenate production. In this study, copper nitride-based materials with varying reduction rates were employed as precatalysts. Consequently, a relationship between the selectivity toward C2+ oxygenates and the Cu oxidation state during the ECOR process is established. Results of theoretical and experimental analyses reveal that the Cu0/Cu+ interface plays a key role in enhancing *CO adsorption while lowering the formation energy of *CH2CO, thereby promoting acetate production. This work highlights the significance of the Cu0/Cu+ interface in the regulation of C2+ oxygenate production and paves the way for the development of highly selective catalysts in the future.

16.
J Biomed Mater Res A ; 112(7): 1149-1163, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38461474

RESUMEN

Diabetic wounds environment is over-oxidized, over-inflammatory, leading to difficulties in regenerating blood vessels, and retardation of healing in diabetic wounds. Therefore, diabetic wounds can be treated from the perspective of scavenging oxidative free radicals and reducing the level of inflammation. Herein, we report a bioactive poly(salicylic acid)-poly(citric acid) (FPSa-PCG) hydrogel for diabetic wound repair. The FPSa-PCG hydrogel shows abilities of antioxidation, anti-inflammation, and regulation of macrophage phenotype. The FPSa-PCG hydrogel showed good biocompatibility, and obtain the abilities of promotion of macrophages migration, reduction of ROS generation, suppression of the M1-type macrophage polarization. FPSa and PCG could synergistically enhance the angiogenesis through upregulating the mRNA expression of HIF1Α, VEGF, and CD31 in endothelial cells and reduce the ROS level of macrophages through upregulating the mRNA expression of Nrf2. The in vivo diabetic wound model confirmed the promoting effect of FPSa-PCG hydrogel on wound closure in diabetes. The further studies found that FPSa-PCG hydrogel could induce the CD31 protein expression in the subcutaneous tissue and inhibit the TNF-a protein expression. This work shows that the simple composition FPSa-PCG hydrogel has a promising therapeutic potential in the treatment of diabetic wounds.


Asunto(s)
Diabetes Mellitus Experimental , Subunidad alfa del Factor 1 Inducible por Hipoxia , Macrófagos , Factor 2 Relacionado con NF-E2 , Cicatrización de Heridas , Animales , Cicatrización de Heridas/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Ratones , Masculino , Andamios del Tejido/química , Hidrogeles/química , Hidrogeles/farmacología , Células RAW 264.7 , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Ratones Endogámicos C57BL , Humanos
17.
BMJ Open ; 14(2): e081050, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38365302

RESUMEN

OBJECTIVES: To aid doctors in selecting the optimal preoperative implantable collamer lens (ICL) size and to enhance the safety and surgical outcomes of ICL procedures, a clinical decision support system (CDSS) is proposed in our study. DESIGN: A retrospective study of patients after ICL surgery. SETTING: China Tertiary Myopia Prevention and Control Center. PARTICIPANTS: 2772 eyes belonging to 1512 patients after ICL surgery. Data were collected between 2018 and 2022. OUTCOME MEASURES: A CDSS is constructed and used to predict vault at 1 month postoperatively and preoperative ICL dimensions using various artificial intelligence methods. Accuracy metrics as well as area under curve (AUC) parameters are used to determine the CDSS prediction methods. RESULTS: Among the ICL size prediction models, conventional neural networks (CNNs) achieve the best prediction accuracy at 91.37% and exhibit the highest AUC of 0.842. Regarding the prediction model for vault values 1 month after surgery, CNN surpasses the other methods with an accuracy of 85.27%, which has the uppermost AUC of 0.815. Thus, we select CNN as the prediction algorithm for the CDSS. CONCLUSIONS: This study introduces a CDSS to assist doctors in selecting the optimal ICL size for patients while improving the safety and postoperative outcomes of ICL surgery.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas , Aprendizaje Profundo , Humanos , Estudios Retrospectivos , Implantación de Lentes Intraoculares/métodos , Agudeza Visual , Inteligencia Artificial
18.
Bioact Mater ; 41: 158-173, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39131630

RESUMEN

Dysregulated inflammation after trauma or infection could result in the further disease and delayed tissue reconstruction. The conventional anti-inflammatory drug treatment suffers to the poor bioavailability and side effects. Herein, we developed an amphiphilic multifunctional poly (citrate-polyglycol-curcumin) (PCGC) nano oligomer with the robust anti-inflammatory activity for treating acute lung injury (ALI) and Methicillin-resistant staphylococcus aureus (MRSA) infected wound. PCGC demonstrated the sustained curcumin release, inherent photoluminescence, good cellular compatibility, hemocompatibility, robust antioxidant activity and enhanced cellular uptake. PCGC could efficiently scavenge nitrogen-based free radicals, oxygen-based free radicals, and intracellular oxygen species, enhance the endothelial cell migration and reduce the expression of pro-inflammatory factors through the NF-κB signal pathway. Combined the anti-inflammation and antioxidant properties, PCGC can shortened the inflammatory process. In animal model of ALI, PCGC was able to reduce the pulmonary edema, bronchial cell infiltration, and lung inflammation, while exhibiting rapid metabolic behavior in vivo. The MRSA-infection wound model showed that PCGC significantly reduced the expression of pro-inflammatory factors, promoted the angiogenesis and accelerated the wound healing. The transcriptome sequencing and molecular mechanism studies further demonstrated that PCGC could inhibit multiple inflammatory related pathways including TNFAIP3, IL-15RA, NF-κB. This work demonstrates that PCGC is efficient in resolving inflammation and promotes the prospect of application in inflammatory diseases as the drug-loaded therapeutic system.

19.
Biosensors (Basel) ; 14(1)2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38248427

RESUMEN

Recently, significant progress has been made in the development of microdevices for point-of-care infectious disease detection. However, most microdevices only allow limited steps, such as DNA amplification on the chip, while sample preparation, such as lysis and DNA extraction, is conducted off the chip using the traditional method. In this study, an all-in-one platform was developed, which incorporated all necessary procedures for nucleic acid detection. Our on-chip DNA extraction method utilized the magnetic bead-based technology on a hybrid channel-digital microfluidics (C-DMF) microdevice. It yielded high recovery rates, varying from 88.43% to 95.83%, with pathogen concentrations of 103-106 CFU/mL. In particular, the on-chip method exhibited significantly higher efficacy compared to the traditional off-chip manual method, for the DNA extraction of E. coli and S. aureus, representing Gram-negative and Gram-positive bacteria, respectively, at a sample concentration of 103 CFU/mL. To address the need for rapid and accessible diagnostics, colorimetric LAMP amplification was integrated into the proposed microdevice. The results were visually detectable with the naked eye, making it user-friendly for non-specialists. In addition, this platform demonstrated impressive sensitivity in simultaneously detecting common foodborne pathogens in spiked meat samples, achieving the LOD of 102-103 CFU/mL. The entire process, from sampling to result, was fully automated and only required approximately 60 min, offering promising applicability in resource-limited and on-site testing scenarios.


Asunto(s)
Escherichia coli , Microfluídica , Staphylococcus aureus , Cromatografía de Afinidad , ADN
20.
Int J Biol Macromol ; 264(Pt 1): 130390, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38403228

RESUMEN

The process of lignin extraction often involves intricate chemical transformations, influencing its potential for high-value utilization. By investigating the process of lignin derivatives extraction from hemp fibers using supercritical CO2, ethanol, and water, we identified the relationship between the chemical structure of lignin derivatives and temperature. This discovery contributes to controlling the chemical structure of lignin derivatives through temperature modulation. We observed that lignin derivatives extracted within the temperature range of 100-120 °C exhibited the lowest average molecular weight and polydispersity index, presenting a disordered microstructure with the highest hydroxyl content. Lignin derivatives extracted between 140 and 160 °C showed an increase in average molecular weight and polydispersity index, decreased hydroxyl content, and a gradual transformation of microstructure into spherical particles. At 180 °C, the average molecular weight and polydispersity index of lignin derivatives decreased, the microstructure of lignin derivatives showed fewer spherical particles, while its hydroxyl content exhibited a partial recovery. Chemical analysis revealed a lower degree of condensation in lignin derivatives at 100-120 °C. Between 120 and 160 °C, the degree of condensation increased. At 180 °C, extensive degradation occurred in lignin derivatives. This research advances innovative techniques for lignin derivative separation, contributing to their utilization in higher-value applications.


Asunto(s)
Cannabis , Lignina , Lignina/química , Etanol/química , Agua/química , Dióxido de Carbono , Temperatura
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