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1.
FASEB J ; 38(15): e23852, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39101942

RESUMEN

Temporomandibular joint osteoarthritis (TMJOA) is a degenerative ailment that causes slow cartilage degeneration, aberrant bone remodeling, and persistent discomfort, leading to a considerable reduction in the patient's life quality. Current treatment options for TMJOA have limited efficacy. This investigation aimed to explore a potential strategy for halting or reversing the progression of TMJOA through the utilization of exosomes (EXOs) derived from urine-derived stem cells (USCs). The USC-EXOs were obtained through microfiltration and ultrafiltration techniques, followed by their characterization using particle size analysis, electron microscopy, and immunoblotting. Subsequently, an in vivo model of TMJOA induced by mechanical force was established. To assess the changes in the cartilage of TMJOA treated with USC-EXOs, we performed histology analysis using hematoxylin-eosin staining, immunohistochemistry, and histological scoring. Our findings indicate that the utilization of USC-EXOs yields substantial reductions in TMJOA, while concurrently enhancing the structural integrity and smoothness of the compromised condylar cartilage surface. Additionally, USC-EXOs exhibit inhibitory effects on osteoclastogenic activity within the subchondral bone layer of the condylar cartilage, as well as attenuated apoptosis in the rat TMJ in response to mechanical injury. In conclusion, USC-EXOs hold considerable promise as a potential therapeutic intervention for TMJOA.


Asunto(s)
Exosomas , Osteoartritis , Articulación Temporomandibular , Exosomas/metabolismo , Animales , Osteoartritis/terapia , Osteoartritis/patología , Osteoartritis/metabolismo , Ratas , Masculino , Humanos , Articulación Temporomandibular/metabolismo , Articulación Temporomandibular/patología , Células Madre/citología , Células Madre/metabolismo , Ratas Sprague-Dawley , Orina/citología , Trastornos de la Articulación Temporomandibular/terapia , Trastornos de la Articulación Temporomandibular/metabolismo , Trastornos de la Articulación Temporomandibular/patología , Femenino , Cartílago Articular/patología , Cartílago Articular/metabolismo
3.
Front Med (Lausanne) ; 11: 1420848, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39139792

RESUMEN

Background: Myopia, strabismus, and ptosis are common pediatric eye diseases, which have a negative impact on children and adolescents in terms of visual function, mental health, and health-related quality of life (HRQoL). Therefore, this study focused on those pediatric eye diseases by analyzing their risk factors and HRQoL for the comprehensive management of myopia, strabismus, and ptosis. Methods: A total of 363 participants (2-18 years old) were included in this study for risk factors analysis of myopia, strabismus, and ptosis. We collected demographic characteristics, lifestyle habits and eye care habits of these children and analyzed them by using univariable and multivariable logistic regression. In addition, we applied the Chinese version of Pediatric Quality of Life Inventory-Version 4.0 (PedsQL 4.0) to assess HRQoL in 256 children with strabismus and ptosis. Univariable and multivariable linear regression models were applied to evaluate potential influencing factors of HRQoL. Results: Of all the participants, 140 had myopia, 127 had strabismus, and 145 had ptosis. Based on the multivariable logistic regression analysis model, we found that the history of parental myopia and daily average near-distance eye usage time were risk factors for myopia, and increased body mass index (BMI) was identified as a risk factor for strabismus and ptosis. Individuals with ptosis possessed decreased HRQoL. The multivariable linear regression model suggested that daily average near-distance eye usage time, light intensity during visual tasks, and daily average sleep duration had potential influences on HRQoL. Conclusion: This is the first study to assess the risk factors and HRQoL of myopia, strabismus, and ptosis together. We identified risk factors for these common pediatric eye diseases to help doctors, parents, and teachers better manage them. Our study discovered that children with eye disorders exhibit a notably diminished HRQoL. Consequently, it emphasizes the necessity for increased social attention and mental health assistance for these children.

4.
Ecotoxicol Environ Saf ; 284: 116879, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39142117

RESUMEN

Pervasive environmental pollutants, specifically particulate matter (PM2.5), possess the potential to disrupt homeostasis of female thyroid hormone (TH). However, the precise mechanism underlying this effect remains unclear. In this study, we established a model of PM2.5-induced thyroid damage in female rats through intratracheal instillation and employed histopathological and molecular biological methods to observe the toxic effects of PM2.5 on the thyroid gland. Transcriptome gene analysis and 16S rRNA sequencing were utilized to investigate the impact of PM2.5 exposure on the female rat thyroid gland. Furthermore, based on the PM2.5-induced toxic model in female rats, we evaluated its effects on intestinal microbiota, TH levels, and indicators of thyroid function. The findings revealed that PM2.5 exposure induced histopathological damage to thyroid tissue by disrupting thyroid hormone levels (total T3 [TT3], (P < 0.05); total T4 [TT4], (P < 0.05); and thyrotropin hormone [TSH], (P < 0.05)) and functional indices (urine iodine [UI], P > 0.05), thus further inducing histopathological injuries. Transcriptome analysis identified differentially expressed genes (DEGs), primarily concentrated in interleukin 17 (IL-17), forkhead box O (FOXO), and other signaling pathways. Furthermore, exposure to PM2.5 altered the composition and abundance of intestinal microbes. Transcriptome and microbiome analyses demonstrated a correlation between the DEGs within these pathways and the flora present in the intestines. Moreover, 16 S rRNA gene sequencing analysis or DEGs combined with thyroid function analysis revealed that exposure to PM2.5 significantly induced thyroid hormone imbalance. We further identified key DEGs involved in thyroid function-relevant pathways, which were validated using molecular biology methods for clinical applications. In conclusion, the homeostasis of the "gut-thyroid" axis may serve as the underlying mechanism for PM2.5-induced thyrotoxicity in female rats.

5.
ACS Synth Biol ; 13(8): 2533-2544, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39090815

RESUMEN

ß-ionone, a norisoprenoid, is a natural aromatic compound derived from plants, which displays various biological activities including anticancer, antioxidant and deworming properties. Due to its large biomass and strong environmental tolerance, the nonconventional oleaginous yeast Candida tropicalis was selected to efficiently synthesize ß-ionone. We initially investigated the capacity of the cytoplasm and subcellular compartments to synthesize ß-ionone independently. Subsequently, through adaptive screening of enzymes, functional identification of subcellular localization signal peptides and subcellular compartment combination strategies, a titer of 152.4 mg/L of ß-ionone was achieved. Finally, directed evolution of rate-limiting enzyme and overexpression of key enzymes were performed to enhance ß-ionone production. The resulting titer was 400.5 mg/L in shake flasks and 730 mg/L in a bioreactor. This study demonstrates the first de novo synthesis of ß-ionone in C. tropicalis, providing a novel cellular chassis for terpenoid fragrances with considerable industrial potential.


Asunto(s)
Candida tropicalis , Ingeniería Metabólica , Norisoprenoides , Candida tropicalis/metabolismo , Candida tropicalis/genética , Ingeniería Metabólica/métodos , Norisoprenoides/metabolismo , Reactores Biológicos
6.
Talanta ; 279: 126672, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39111219

RESUMEN

Spinal cord injury (SCI) is a debilitating neurological and pathological condition that results in significant impairments in motor, sensory, and autonomic functions. By integrating multispectral imaging (MSI) with Raman spectroscopy, a label-free optical methodology was developed for achieving a non-invasive in vivo understanding on the pathological features of SCI evolution. Under the guidance of captured the spectral imaging data cube with a rigid endoscope based MSI system, a special designed fiber probe passed through the instrumental channel for acquiring the finger-print spectral information from compression rat SCI models. After identifying the main visual features of injured spinal cord tissue in all Sham, 0-, 3- and 7-days post injury (0 DPI, 3 DPI, and 7 DPI) groups, the blood volume and oxygen content were visualized to describe hemorrhage, hypoxia and inflammatory state after acute injury. The averaged reflectance spectra, which were deduced from MSI data cubes, were utilized for describing oxygen saturation and hemoglobin concentration in living tissue. The results of Raman spectroscopy addressed complex compositional and conformational phenomena during SCI progression, correlated with the well-known event like neuronal apoptosis, hemorrhage, demyelination, and even the upregulation of chondroitin sulfate proteoglycans (CSPGs). A principal component analysis and linear discriminate algorithm (PCA-LDA) based discriminate model was introduced for categorizing spectral features in different injury stages, which was applicable for intraoperative interpretations on the complex pathological courses of SCI and therapeutic outcomes.

7.
J Orthop Surg Res ; 19(1): 474, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39127696

RESUMEN

Anterior talofibular ligament injuries and osteochondral lesions of the talus present unique challenges to orthopedic surgeons. This study aimed to investigate the relevant relationship between them by analyzing the Magnetic resonance imaging (MRI) results of clinical patients and single-cell RNA sequence (scRNA seq) results of healthy talus cartilage to discuss the risk factors. Data from 164 patients from 2018 to 2023 was retrospectively analyzed. The correlation analysis between ATFL injury grade and the Hepple stage of OLT determined by MRI was performed. Publicly available single-cell RNA datasets were collected. Single-cell RNA datasets from five volunteers of healthy talus cartilage were analyzed. ATFL injury grade was relevant with the Hepple stage of OLT (P < 0.05). The results of multivariate logistic regression analysis showed that injured area was the independent influencing factor of the incidence rate and the severity of OLT (P < 0.05). The Hepple stage of OLT was relevant with AOFAS and VAS (P < 0.05). Single-cell RNA sequence results showed that among the 9 subtypes of chondrocytes, the interaction strength between HTC-A and HTC-B is the highest. Their physical interactions are mainly achieved through the CD99 signaling pathway, and factor interactions are mainly achieved through the ANGPTL signaling pathway. Anterior talofibular ligament injury may lead to osteochondral lesions of the talus. Early medical intervention should be carried out for ligament injuries to restore joint stability and avoid cartilage damage.


Asunto(s)
Ligamentos Laterales del Tobillo , Imagen por Resonancia Magnética , Astrágalo , Humanos , Astrágalo/lesiones , Astrágalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Masculino , Femenino , Adulto , Estudios Retrospectivos , Ligamentos Laterales del Tobillo/lesiones , Ligamentos Laterales del Tobillo/diagnóstico por imagen , Adulto Joven , Persona de Mediana Edad , Análisis de la Célula Individual/métodos , Cartílago Articular/lesiones , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/patología , Condrocitos/metabolismo , Traumatismos del Tobillo/diagnóstico por imagen , Adolescente , Análisis de Secuencia de ARN/métodos
8.
Phytochemistry ; 228: 114241, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39122160

RESUMEN

Six pairs of previously undescribed enantiomeric phytocannabinoid-like meroterpenoids, (±)-spinulinoids A‒F, and two naturally occurring compounds, (+)-rhododaurichromanic acid A and (E)-4-((3,7-dimethylocta-2,6-dien-1-yl)oxy)benzoic acid, together with one known congener, (-)-rhododaurichromanic acid A, were obtained from the twigs and leaves of Rhododendron spinuliferum. Their structures were established by their extensive spectral data (NMR and HRESIMS), ECD calculations, and single-crystal X-ray diffraction data. Spinulinoids A and B are unprecedented phytocannabinoid-like meroterpenoids constructed by the resorcinol moiety and a ß-bisabolene unit, whereas spinulinoid C represents a rare adduct of quinone and ß-bisabolene with a tricyclic 6/6/6 ring system.

9.
Pharmacol Res ; 207: 107341, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39134188

RESUMEN

Drug conjugates are obtained from tumor-located vectors connected to cytotoxic agents via linkers, which are designed to deliver hyper-toxic payloads directly to targeted cancer cells. These drug conjugates include antibody-drug conjugates (ADCs), peptide-drug conjugates (PDCs), small molecule-drug conjugates (SMDCs), nucleic acid aptamer-drug conjugates (ApDCs), and virus-like drug conjugate (VDCs), which show great therapeutic value in the clinic. Drug conjugates consist of a targeting carrier, a linker, and a payload. Payloads are key therapy components. Cytotoxic molecules and their derivatives derived from natural products are commonly used in the payload portion of conjugates. The ideal payload should have sufficient toxicity, stability, coupling sites, and the ability to be released under specific conditions to kill tumor cells. Microtubule protein inhibitors, DNA damage agents, and RNA inhibitors are common cytotoxic molecules. Among these conjugates, cytotoxic molecules of natural origin are summarized based on their mechanism of action, conformational relationships, and the discovery of new derivatives. This paper also mentions some cytotoxic molecules that have the potential to be payloads. It also summarizes the latest technologies and novel conjugates developed in recent years to overcome the shortcomings of ADCs, PDCs, SMDCs, ApDCs, and VDCs. In addition, this paper summarizes the clinical trials conducted on conjugates of these cytotoxic molecules over the last five years. It provides a reference for designing and developing safer and more efficient conjugates.

10.
J Am Soc Nephrol ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39137052

RESUMEN

BACKGROUND: IgA nephropathy is an important global cause of kidney failure. Dysregulation of IgA production is thought to play a key role in IgA nephropathy pathogenesis, however, little is known about the epigenetic mechanisms such as RNA 5- methylcytosine (5mC) modification in regulating IgA synthesis. METHODS: To decipher the role of RNA 5mC in regulation of IgA class switch, the miR-23b-/- and LCWE induced Kawasaki disease mice were treated with 5-azacytidine. Trdmt1-/- and double Trdmt1-/-/ miR-23b-/- mice, Aid-/- mice or Aid-/-/ miR-23b-/- mice were also employed. RESULTS: We showed that miR-23b down regulated expression of Transfer RNA Aspartic Acid Methyltransferase 1 (Trdmt1) and consequently reduced 5-methylcytosine (m5C) RNA modification and IgA synthesis in B cells. Inhibition of m5C RNA modification normalised serum IgA levels and ameliorated progression of the IgA nephropathy-like kidney disease in miR-23b-/- and Kawasaki disease mice while mesangial IgA and C3 deposition failed to develop in Trdmt1-/-miR-23b-/- mice. By contrast, increased m5C RNA modification resulted in an exaggerated IgA nephropathy phenotype. miR-23b regulation of serum IgA levels and the development of an IgA nephropathy-like kidney disease in miR-23b-/- and Kawasaki disease mice is likely mediated through TRDMT1 driven 5-methylcytosine RNA modification in B cells, resulting in impaired activation-induced cytidine deaminase activity and IgA class switch recombination. CONCLUSIONS: This study revealed TRDMT1 induced RNA 5mC methylation regulate IgA class switch and inhibition of RNA 5mC by 5-Azacytidine could ameliorate progression of IgA nephropathy.

11.
JAMA Netw Open ; 7(8): e2425124, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39106068

RESUMEN

IMPORTANCE: Identifying pediatric eye diseases at an early stage is a worldwide issue. Traditional screening procedures depend on hospitals and ophthalmologists, which are expensive and time-consuming. Using artificial intelligence (AI) to assess children's eye conditions from mobile photographs could facilitate convenient and early identification of eye disorders in a home setting. OBJECTIVE: To develop an AI model to identify myopia, strabismus, and ptosis using mobile photographs. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study was conducted at the Department of Ophthalmology of Shanghai Ninth People's Hospital from October 1, 2022, to September 30, 2023, and included children who were diagnosed with myopia, strabismus, or ptosis. MAIN OUTCOMES AND MEASURES: A deep learning-based model was developed to identify myopia, strabismus, and ptosis. The performance of the model was assessed using sensitivity, specificity, accuracy, the area under the curve (AUC), positive predictive values (PPV), negative predictive values (NPV), positive likelihood ratios (P-LR), negative likelihood ratios (N-LR), and the F1-score. GradCAM++ was utilized to visually and analytically assess the impact of each region on the model. A sex subgroup analysis and an age subgroup analysis were performed to validate the model's generalizability. RESULTS: A total of 1419 images obtained from 476 patients (225 female [47.27%]; 299 [62.82%] aged between 6 and 12 years) were used to build the model. Among them, 946 monocular images were used to identify myopia and ptosis, and 473 binocular images were used to identify strabismus. The model demonstrated good sensitivity in detecting myopia (0.84 [95% CI, 0.82-0.87]), strabismus (0.73 [95% CI, 0.70-0.77]), and ptosis (0.85 [95% CI, 0.82-0.87]). The model showed comparable performance in identifying eye disorders in both female and male children during sex subgroup analysis. There were differences in identifying eye disorders among different age subgroups. CONCLUSIONS AND RELEVANCE: In this cross-sectional study, the AI model demonstrated strong performance in accurately identifying myopia, strabismus, and ptosis using only smartphone images. These results suggest that such a model could facilitate the early detection of pediatric eye diseases in a convenient manner at home.


Asunto(s)
Inteligencia Artificial , Diagnóstico Precoz , Fotograbar , Humanos , Femenino , Masculino , Estudios Transversales , Niño , Preescolar , Fotograbar/métodos , Miopía/diagnóstico , Aprendizaje Profundo , Estrabismo/diagnóstico , Blefaroptosis/diagnóstico , Sensibilidad y Especificidad , China/epidemiología , Oftalmopatías/diagnóstico , Adolescente
12.
Heliyon ; 10(14): e34616, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39114017

RESUMEN

In the realm of classroom assessment, the shift towards "assessment as learning" underscores the pivotal role of students in developing assessment literacy. This study aims to bridge the gap in the literature by examining the understudied area of students' assessment literacy. The author introduces a novel chain mediation effect structure model to investigate the interactions between teacher autonomy support, self-efficacy, critical reflection, and students' assessment literacy. The sample comprises 704 high school students from central China, with an even gender distribution (321 boys and 383 girls), which provides a robust dataset for analysis. By utilizing the Student Evaluative Scale, Critical Reflection Scale, and Self-Efficacy Scale, the study reveals a significant and positive correlation between teacher autonomy support and the level of assessment literacy among students. Furthermore, the findings indicate that self-efficacy and critical reflection act as mediators in the relationship between teacher autonomy support and students' assessment literacy. This suggests that educators who foster an environment of autonomy, empowering students to take ownership of their learning, can significantly enhance students' belief in their own abilities (self-efficacy) and their capacity for reflective thinking, thereby improving students' assessment literacy. The study concludes with concrete suggestions for classroom practice and identifies avenues for future research to further refine our understanding of the complex interplay between teacher support, student self-efficacy, critical reflection, and assessment literacy.

13.
Cell Rep ; 43(8): 114609, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39116210

RESUMEN

The NLRP3 inflammasome is dysregulated in autoinflammatory disorders caused by inherited mutations and contributes to the pathogenesis of several chronic inflammatory diseases. In this study, we discovered that disulfiram, a safe US Food and Drug Administration (FDA)-approved drug, specifically inhibits the NLRP3 inflammasome but not the NLRC4 or AIM2 inflammasomes. Disulfiram suppresses caspase-1 activation, ASC speck formation, and pyroptosis induced by several stimuli that activate NLRP3. Mechanistically, NLRP3 is palmitoylated at cysteine 126, a modification required for its localization to the trans-Golgi network and inflammasome activation, which was inhibited by disulfiram. Administration of disulfiram to animals inhibited the NLRP3, but not NLRC4, inflammasome in vivo. Our study uncovers a mechanism by which disulfiram targets NLRP3 and provides a rationale for using a safe FDA-approved drug for the treatment of NLRP3-associated inflammatory diseases.

14.
Clin Kidney J ; 17(8): sfae209, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39145144

RESUMEN

Background: This study investigates the link between genetic variants associated with kidney function and immunoglobulin A (IgA) nephropathy (IgAN) progression. Methods: We recruited 961 biopsy-proven IgAN patients and 651 non-IgAN end-stage renal disease (ESRD) patients from Ruijin Hospital. Clinical and renal pathological data were collected. The primary outcome was the time to ESRD. A healthy population was defined as estimated glomerular filtration rate >60 mL/min/1.73 m2 without albuminuria or hematuria. Fifteen single-nucleotide polymorphisms (SNPs) were selected from a genome-wide association study of kidney function and genotyped by the SNaPshot. Immunohistochemistry in renal tissue and ELISA in urine samples were performed to explore the potential functions of genetic variations. Results: The rs77924615-G was independently associated with an increased risk for ESRD in IgAN patients after adjustments for clinical and pathologic indices, and treatment (adjusted hazard ratio 2.10; 95% confidence interval 1.14-3.88). No significant differences in ESRD-free survival time were found among different genotypes in non-IgAN ESRD patients (log-rank, P = .480). Moreover, rs77924615 exhibited allele-specific enhancer activity by dual-luciferase reporter assay. Accordingly, the urinary uromodulin-creatinine ratio (uUCR) was significantly higher in healthy individuals with rs77924615 AG or GG than in individuals with AA. Furthermore, uromodulin expression in tubular epithelial cells was higher in patients with rs77924615 AG or GG. Finally, we confirmed that an increased uUCR (P = .009) was associated with faster IgAN progression. Conclusion: The SNP rs77924615, which modulates the enhancer activity of the UMOD gene, is associated with renal function deterioration in IgAN patients by increasing uromodulin levels in both the renal tubular epithelium and urine.

15.
Fitoterapia ; 178: 106171, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39111719

RESUMEN

Euphorbiabietane F (1), a novel abietane diterpenoid with the unprecedented 6/6/5/6/5 carbon skeleton, one new strobane diterpenoid (2), together with one new pimarane diterpenoid (3) were isolated from the roots of Euphorbia fischeriana. The structures were elucidated by the extensive spectroscopic data, gauge-independent atomic orbital (GIAO) NMR calculations, the comparison of experimental and calculated ECD spectra, as well as single crystal X-ray diffraction. The cytotoxicity result suggested the moderate inhibition rate of 1 on the cell lines of HepG2 and A549.

16.
Sci Total Environ ; 950: 175357, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39127203

RESUMEN

Klebsiella pneumoniae (Kp) is a human symbiotic opportunistic pathogen capable of causing severe hospital-based infections and community-acquired infections. The problem of antimicrobial resistance (AMR) has become increasing serious over time, posing a major threat to socio-economic and human development. In this study, we explored the global trend of AMR in 1786 strains of Kp isolated between 1982 and 2023. The number of antibiotic resistance genes (ARGs) in Kp increased significantly from 24.29 ± 5.44 to 32.42 ± 8.52 over time. Mobile genetic elements (MGEs) were responsible for the ARGs horizontal transfer of Kp strains. The results of structural equation modeling (SEM) indicated a strong association between the human development index and the increase of antibiotic consumption, which indirectly affected the occurrence and development of antibiotic resistance in Kp. The results of Generalized Linear Models (GLM) indicated that the influence of environmental factors such as temperature on the development of Kp resistance could not be ignored. Overall, this study monitored the longitudinal trend of antimicrobial resistance in Kp, explored the factors influencing antibiotic resistance, and provided insights for mitigating the threat of antimicrobial resistance.

17.
Int J Biol Macromol ; 277(Pt 4): 134534, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39111464

RESUMEN

A fungal laccase-mediator system capable of high effectively oxidizing tetracyclines under a wide pH range will benefit environmental protection. This study reported a directed evolution of a laccase PIE5 to improve its performance on tetracyclines oxidization at alkaline conditions. Two mutants, namely MutA (D229N/A244V) and MutB (N123A/D229N/A244V) were obtained. Although they shared a similar optimum pH and temperature as PIE5, the two mutants displayed approximately 2- and 5-fold higher specific activity toward the mediators ABTS and guaiacol at pHs 4.0 to 6.5, respectively. Simultaneously, their catalytic efficiency increased by 8.0- and 6.4-fold compared to PIE5. At a pH range of 5-8 and 28 °C, MutA or MutB at a final concentration of 2.5 U·mL-1 degraded 77 % and 81 % of 100 mg·L-1 tetracycline within 10 min, higher than PIE5 (45 %). Furthermore, 0.1 U·mL-1 MutA or MutB completely degraded 100 mg·L-1 chlortetracycline within 6 min in the presence of 0.1 mM ABTS. At pH 8.0, MutA degraded tetracycline and chlortetracycline following the routine pathways were reported previously based on LC-MS analysis.

18.
Nat Commun ; 15(1): 6791, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39117735

RESUMEN

Site-selective C(sp3)-H arylation is an appealing strategy to synthesize complex arene structures but remains a challenge facing synthetic chemists. Here we report the use of photoredox-mediated hydrogen atom transfer (HAT) catalysis to accomplish the site-selective α-C(sp3)-H arylation of dialkylamine-derived ureas through 1,4-radical aryl migration, by which a wide array of benzylamine motifs can be incorporated to the medicinally relevant systems in the late-stage installation steps. In contrast to previous efforts, this C-H arylation protocol exhibits specific site-selectivity, proforming predominantly on sterically more-hindered secondary and tertiary α-amino carbon centers, while the C-H functionalization of sterically less-hindered N-methyl group can be effectively circumvented in most cases. Moreover, a diverse range of multi-substituted piperidine derivatives can be obtained with excellent diastereoselectivity. Mechanistic and computational studies demonstrate that the rate-determining step for methylene C-H arylation is the initial H atom abstraction, whereas the radical ipso cyclization step bears the highest energy barrier for N-methyl functionalization. The relatively lower activation free energies for secondary and tertiary α-amino C-H arylation compared with the functionalization of methylic C-H bond lead to the exceptional site-selectivity.

19.
Genome Med ; 16(1): 96, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39123268

RESUMEN

BACKGROUND: Immunoglobulin (Ig) glycosylation modulates the immune response and plays a critical role in ageing and diseases. Studies have mainly focused on IgG glycosylation, and little is known about the genetics and epidemiology of IgA glycosylation. METHODS: We generated, using a novel liquid chromatography-mass spectrometry method, the first large-scale IgA glycomics dataset in serum from 2423 twins, encompassing 71 N- and O-glycan species. RESULTS: We showed that, despite the lack of a direct genetic template, glycosylation is highly heritable, and that glycopeptide structures are sex-specific, and undergo substantial changes with ageing. We observe extensive correlations between the IgA and IgG glycomes, and, exploiting the twin design, show that they are predominantly influenced by shared genetic factors. A genome-wide association study identified eight loci associated with both the IgA and IgG glycomes (ST6GAL1, ELL2, B4GALT1, ABCF2, TMEM121, SLC38A10, SMARCB1, and MGAT3) and two novel loci specifically modulating IgA O-glycosylation (C1GALT1 and ST3GAL1). Validation of our findings in an independent cohort of 320 individuals from Qatar showed that the underlying genetic architecture is conserved across ancestries. CONCLUSIONS: Our study delineates the genetic landscape of IgA glycosylation and provides novel potential functional links with the aetiology of complex immune diseases, including genetic factors involved in IgA nephropathy risk.


Asunto(s)
Estudio de Asociación del Genoma Completo , Glicómica , Inmunoglobulina A , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina A/genética , Glicosilación , Femenino , Masculino , Polisacáridos/metabolismo , Adulto , Inmunoglobulina G/sangre , Persona de Mediana Edad , Anciano
20.
Materials (Basel) ; 17(15)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39124453

RESUMEN

Flexible thermoelectric materials have drawn significant attention from researchers due to their potential applications in wearable electronics and the Internet of Things. Despite many reports on these materials, it remains a significant challenge to develop cost-effective methods for large-scale, patterned fabrication of materials that exhibit both excellent thermoelectric performance and remarkable flexibility. In this study, we have developed an Ag2Se-based ink with excellent printability that can be used to fabricate flexible thermoelectric films by screen printing and low-temperature sintering. The printed films exhibit a Seebeck coefficient of -161 µV/K and a power factor of 3250.9 µW/m·K2 at 400 K. Moreover, the films demonstrate remarkable flexibility, showing minimal changes in resistance after being bent 5000 times at a radius of 5 mm. Overall, this research offers a new opportunity for the large-scale patterned production of flexible thermoelectric films.

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