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1.
Cell ; 168(1-2): 172-185.e15, 2017 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-28086090

RESUMEN

Pathogenic Vibrio cholerae remains a major human health concern. V. cholerae has a characteristic curved rod morphology, with a longer outer face and a shorter inner face. The mechanism and function of this curvature were previously unknown. Here, we identify and characterize CrvA, the first curvature determinant in V. cholerae. CrvA self-assembles into filaments at the inner face of cell curvature. Unlike traditional cytoskeletons, CrvA localizes to the periplasm and thus can be considered a periskeletal element. To quantify how curvature forms, we developed QuASAR (quantitative analysis of sacculus architecture remodeling), which measures subcellular peptidoglycan dynamics. QuASAR reveals that CrvA asymmetrically patterns peptidoglycan insertion rather than removal, causing more material insertions into the outer face than the inner face. Furthermore, crvA is quorum regulated, and CrvA-dependent curvature increases at high cell density. Finally, we demonstrate that CrvA promotes motility in hydrogels and confers an advantage in host colonization and pathogenesis.


Asunto(s)
Vibrio cholerae/citología , Vibrio cholerae/patogenicidad , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Locomoción , Ratones , Peptidoglicano/metabolismo , Periplasma/metabolismo , Alineación de Secuencia , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Virulencia
2.
J Am Chem Soc ; 146(18): 12723-12733, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38654452

RESUMEN

Enfumafungin-type antibiotics, represented by enfumafungin and fuscoatroside, belong to a distinct group of triterpenoids derived from fungi. These compounds exhibit significant antifungal properties with ibrexafungerp, a semisynthetic derivative of enfumafungin, recently gaining FDA's approval as the first oral antifungal drug for treating invasive vulvar candidiasis. Enfumafungin-type antibiotics possess a cleaved E-ring with an oxidized carboxyl group and a reduced methyl group at the break site, suggesting unprecedented C-C bond cleavage chemistry involved in their biosynthesis. Here, we show that a 4-gene (fsoA, fsoD, fsoE, fsoF) biosynthetic gene cluster is sufficient to yield fuscoatroside by heterologous expression in Aspergillus oryzae. Notably, FsoA is an unheard-of terpene cyclase-glycosyltransferase fusion enzyme, affording a triterpene glycoside product that relies on enzymatic fusion. FsoE is a P450 enzyme that catalyzes successive oxidation reactions at C19 to facilitate a C-C bond cleavage, producing an oxidized carboxyl group and a reduced methyl group that have never been observed in known P450 enzymes. Our study thus sets the important foundation for the manufacture of enfumafungin-type antibiotics using biosynthetic approaches.


Asunto(s)
Antifúngicos , Antifúngicos/química , Antifúngicos/farmacología , Antifúngicos/metabolismo , Aspergillus oryzae/enzimología , Aspergillus oryzae/metabolismo , Familia de Multigenes , Triterpenos/química , Triterpenos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo
3.
Biomarkers ; 29(4): 185-193, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38568742

RESUMEN

BACKGROUND: Extra spindle pole bodies-like 1 (ESPL1) is known to play a crucial role in the segregation of sister chromatids during mitosis. Overexpression of ESPL1 is considered to have oncogenic effects in various human cancers. However, the specific biological function of ESPL1 in endometrial cancer (EC) remains unclear. METHODS: The TCGA and GEO databases were utilized to assess the expression of ESPL1 in EC. Immunohistochemistry was utilized to detect separase expression in EC samples. Kaplan-Meier survival analysis and Cox regression analysis were performed to evaluate the diagnostic and prognostic significance of ESPL1 in EC. Gene Set Enrichment Analysis (GSEA) was employed to explore the potential signaling pathway of ESPL1 in EC. Cell proliferation and colony formation ability were analyzed using CCK-8 and colony formation assay. RESULTS: Our analysis revealed that ESPL1 is significantly upregulated in EC, and its overexpression is associated with advanced clinical characteristics and unfavourable prognostic outcomes. Suppression of ESPL1 attenuated proliferation of EC cell line. CONCLUSION: The upregulation of ESPL1 is associated with advanced disease and poor prognosis in EC patients. These findings suggest that ESPL1 has the potential to serve as a diagnostic and prognostic biomarker in EC, highlighting its significance in the management of EC patients.


The expression of ESPL1 was higher in EC tissue than normal endometrial tissue.ESPL1 could be a potential prognostic marker for EC.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Endometriales , Separasa , Regulación hacia Arriba , Femenino , Humanos , Persona de Mediana Edad , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , Neoplasias Endometriales/genética , Neoplasias Endometriales/metabolismo , Neoplasias Endometriales/patología , Regulación Neoplásica de la Expresión Génica , Estimación de Kaplan-Meier , Pronóstico , Separasa/metabolismo , Separasa/genética
4.
J Biol Chem ; 298(9): 102372, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35970391

RESUMEN

Nitrogen (N2) gas in the atmosphere is partially replenished by microbial denitrification of ammonia. Recent study has shown that Alcaligenes ammonioxydans oxidizes ammonia to dinitrogen via a process featuring the intermediate hydroxylamine, termed "Dirammox" (direct ammonia oxidation). However, the unique biochemistry of this process remains unknown. Here, we report an enzyme involved in Dirammox that catalyzes the conversion of hydroxylamine to N2. We tested previously annotated proteins involved in redox reactions, DnfA, DnfB, and DnfC, to determine their ability to catalyze the oxidation of ammonia or hydroxylamine. Our results showed that none of these proteins bound to ammonia or catalyzed its oxidation; however, we did find DnfA bound to hydroxylamine. Further experiments demonstrated that, in the presence of NADH and FAD, DnfA catalyzed the conversion of 15N-labeled hydroxylamine to 15N2. This conversion did not happen under oxygen (O2)-free conditions. Thus, we concluded that DnfA encodes a hydroxylamine oxidase. We demonstrate that DnfA is not homologous to any known hydroxylamine oxidoreductases and contains a diiron center, which was shown to be involved in catalysis via electron paramagnetic resonance experiments. Furthermore, enzyme kinetics of DnfA were assayed, revealing a Km of 92.9 ± 3.0 µM for hydroxylamine and a kcat of 0.028 ± 0.001 s-1. Finally, we show that DnfA was localized in the cytoplasm and periplasm as well as in tubular membrane invaginations in HO-1 cells. To the best of our knowledge, we conclude that DnfA is the first enzyme discovered that catalyzes oxidation of hydroxylamine to N2.


Asunto(s)
Alcaligenes , Amoníaco , Hidroxilaminas , Oxidorreductasas , Alcaligenes/enzimología , Amoníaco/metabolismo , Proteínas Bacterianas/metabolismo , Flavina-Adenina Dinucleótido/metabolismo , Hidroxilaminas/metabolismo , NAD/metabolismo , Nitrógeno/metabolismo , Oxidación-Reducción , Oxidorreductasas/metabolismo , Oxígeno
5.
Plant Mol Biol ; 113(1-3): 59-74, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37634200

RESUMEN

Leaves are the primary photosynthetic organs, providing essential substances for tree growth. It is important to obtain an anatomical understanding and regulatory network analysis of leaf development. Here, we studied leaf development in Populus Nanlin895 along a development gradient from the newly emerged leaf from the shoot apex to the sixth leaf (L1 to L6) using anatomical observations and RNA-seq analysis. It indicated that mesophyll cells possess obvious vascular, palisade, and spongy tissue with distinct intercellular spaces after L3. Additionally, vacuoles fuse while epidermal cells expand to form pavement cells. RNA-seq analysis indicated that genes highly expressed in L1 and L2 were related to cell division and differentiation, while those highly expressed in L3 were enriched in photosynthesis. Therefore, we selected L1 and L3 to integrate ATAC-seq and RNA-seq and identified 735 differentially expressed genes (DEGs) with changes in chromatin accessibility regions within their promoters, of which 87 were transcription factors (TFs), such as ABI3VP1, AP-EREBP, MYB, NAC, and GRF. Motif enrichment analysis revealed potential regulatory functions for the DEGs through upstream TFs including TCP, bZIP, HD-ZIP, Dof, BBR-BPC, and MYB. Overall, our research provides a potential molecular foundation for regulatory network exploration in leaf development during photosynthesis establishment.

6.
Cancer Sci ; 114(5): 1882-1897, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36445120

RESUMEN

Naked cuticle homolog 1 (NKD1), which is expressed at low levels in many tumors, is considered an inhibitor of the Wnt/ß-catenin pathway, but it is highly expressed in colon cancer and can promote colon cancer cell proliferation. miRNAs are involved in the occurrence and progression of many tumors. However, miRNAs that can regulate NKD1 and the mechanisms by which NKD1 regulates tumor progression remain ambiguous. This research aims to reveal the potential regulatory network of NKD1 in colon cancer. miRNA data downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were analyzed by bioinformatics to screen for potential miRNAs targeting NKD1. Let-7b-5p was found to inhibit proliferation, migration, and invasion of colon cancer cells targeting NKD1. Further studies suggested that let-7b-5p can modulate Wnt signaling activity, and the nuclear accumulation of ß-catenin was significantly restrained by let-7b-5p through targeting NKD1. Moreover, NKD1 could prohibit the expression of the APC protein. Further studies manifested that NKD1 bound to APC and promoted the ubiquitination degradation of APC through restraining the expression of the deubiquitinating enzyme USP15 and blocking the combination between USP15 and APC. Functionally, NKD1 enhanced the proliferation and migration of colon cancer cells by inhibiting APC expression. This research revealed a novel mechanism by which the let-7b-5p-NKD1-APC-ß-catenin signaling pathway inhibited colon cancer cell progression.


Asunto(s)
Proteína de la Poliposis Adenomatosa del Colon , Proteínas de Unión al Calcio , Neoplasias del Colon , MicroARNs , Vía de Señalización Wnt , Humanos , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Proteínas de Unión al Calcio/metabolismo , Línea Celular Tumoral , Proliferación Celular , Neoplasias del Colon/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , MicroARNs/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo , Proteína de la Poliposis Adenomatosa del Colon/metabolismo
7.
Hum Mol Genet ; 30(21): 1919-1931, 2021 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-34124757

RESUMEN

Sturge-Weber syndrome (SWS) is a neurocutaneous disorder characterized by vascular malformations affecting skin, eyes and leptomeninges of the brain, which can lead to glaucoma, seizures and intellectual disability. The discovery of a disease-causing somatic missense mutation in the GNAQ gene, encoding an alpha chain of heterotrimeric G-proteins, has initiated efforts to understand how G-proteins contribute to SWS pathogenesis. The mutation is predominantly detected in endothelial cells and is currently believed to affect downstream MAPK signalling. In this study of six Norwegian patients with classical SWS, we aimed to identify somatic mutations through deep sequencing of DNA from skin biopsies. Surprisingly, one patient was negative for the GNAQ mutation, but instead harbored a somatic mutation in GNB2 (NM_005273.3:c.232A>G, p.Lys78Glu), which encodes a beta chain of the same G-protein complex. The positions of the mutant amino acids in the G-protein are essential for complex reassembly. Therefore, failure of reassembly and continuous signalling is a likely consequence of both mutations. Ectopic expression of mutant proteins in endothelial cells revealed that expression of either mutant reduced cellular proliferation, yet regulated MAPK signalling differently, suggesting that dysregulated MAPK signalling cannot fully explain the SWS phenotype. Instead, both mutants reduced synthesis of Yes-associated protein (YAP), a transcriptional co-activator of the Hippo signalling pathway, suggesting a key role for this pathway in the vascular pathogenesis of SWS. The discovery of the GNB2 mutation sheds novel light on the pathogenesis of SWS and suggests that future research on targets of treatment should be directed towards the YAP, rather than the MAPK, signalling pathway.


Asunto(s)
Proteínas de Unión al GTP/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Mutación , Síndrome de Sturge-Weber/diagnóstico , Síndrome de Sturge-Weber/genética , Adolescente , Adulto , Niño , Análisis Mutacional de ADN , Proteínas de Unión al GTP/química , Frecuencia de los Genes , Estudios de Asociación Genética/métodos , Humanos , Persona de Mediana Edad , Modelos Moleculares , Nortriptilina , Fenotipo , Conformación Proteica , Subunidades de Proteína/genética , Relación Estructura-Actividad , Secuenciación del Exoma , Adulto Joven
8.
Plant Biotechnol J ; 21(8): 1542-1559, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37057908

RESUMEN

High-temperature (HT) stress at flowering stage causes significant damage to soybean, including pollen abortion and fertilization failure, but few genes involved in male fertility regulation under HT stress in soybean have been characterized. Here, we demonstrated that miR156b-GmSPL2b module involved in male fertility regulation of soybean cytoplasmic male sterility (CMS)-based restorer line under HT stress. Overexpression of miR156b decreased male fertility in soybean CMS-based restorer line and its hybrid F1 with CMS line under HT stress. RNA-seq analysis found that miR156b mediated male fertility regulation in soybean under HT stress by regulating the expression of pollen development and HT response related genes. Metabolomic analysis of miR156bOE revealed reduction in flavonoid content under HT stress. Integrated transcriptomic and metabolomic analysis showed that the overexpression of miR156b caused flavonoid metabolism disorder in soybean flower bud under HT stress. Knockout of GmSPL2b also decreased the thermotolerance of soybean CMS-based restorer line during flowering. Moreover, GmSPL2b turned out to be directly bounded to the promoter of GmHSFA6b. Further verification indicated that GmHSFA6b overexpression enhanced HT tolerance in Arabidopsis during flowering. Substance content and gene expression analysis revealed that miR156b-GmSPL2b may mediate reactive oxygen species clearance by regulating flavonoid metabolism, thus participating in the regulation of male fertility in soybean under HT stress. This study not only provided important progress for understanding the molecular mechanism of miR156b-GmSPL2b regulating the male fertility of soybean CMS-based restorer line under HT stress, but also provided genetic resources and theoretical basis for creating HT-tolerant strong restorer lines.


Asunto(s)
Glycine max , Infertilidad Vegetal , Glycine max/genética , Infertilidad Vegetal/genética , Temperatura , Citosol , Fertilidad/genética , Citoplasma/genética
9.
Org Biomol Chem ; 21(35): 7141-7150, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37608696

RESUMEN

Bisabosqual-type meroterpenoids are fungi-derived polyketide-terpenoid hybrids bearing a 2,3,3a,3a1,9,9a-hexahydro-1H-benzofuro[4,3,2-cde]chromene skeleton (6/6/6/5 ring system) or its seco-C-ring structure, and exhibit diverse bioactivities. Their unique structural architecture and impressive biological activities have led to considerable interest in discovering new analogues. However, to date, only nine analogues have been identified. Herein, we reported the isolation and identification of six new bisabosqual-type meroterpenoids stachybisbins C-H (1-6), together with one known compound bisabosqual C (7), from Stachybotrys bisbyi PYH05-7. Intriguingly, we found that 7, which contains the intact tetracyclic skeleton, can be non-enzymatically converted into its seco derivative stachybisbin I (8), unveiling the biosynthetic relationship between bisabosquals and seco-bisabosquals. Moreover, based on CRISPR/Cas9-mediated gene disruption, we revealed that the three-gene cluster responsible for the formation of LL-Z1272ß is associated with the biosynthesis of bisabosqual-type meroterpenoids, and then proposed a plausible route to 1-8.


Asunto(s)
Benzopiranos , Policétidos , Radiofármacos , Terpenos
10.
Org Biomol Chem ; 21(4): 851-857, 2023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36602159

RESUMEN

Fernane-type triterpenoids are a small group of natural products mainly found in plants and fungi with a wide range of biological activities. Polytolypin is a representative fernane-type triterpenoid from fungi and possesses potent antifungal activity. So far, biosynthesis of fungal-derived fernane-type triterpenoids has not been characterized, which hinders the expansion of their structural diversity using biosynthetic approaches. Herein, we identified the biosynthetic gene cluster of polytolypin and elucidated its biosynthetic pathway through heterologous expression in Aspergillus oryzae NSAR1, which involves a new triterpene cyclase for the biosynthesis of the hydrocarbon skeleton motiol, followed by multiple oxidations via three P450 enzymes. Moreover, two new triterpene cyclases for the biosynthesis of two other fernane-type skeletons isomotiol and fernenol were identified from fungi, and were individually co-expressed with the three P450 enzymes involved in polytolypin biosynthesis. These studies led to the generation of 13 fernane-type triterpenoids including eight new compounds, and two of them showed stronger antifungal activity towards Candida albicans FIM709 than polytolypin.


Asunto(s)
Antifúngicos , Triterpenos , Antifúngicos/farmacología , Triterpenos/farmacología , Triterpenos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Triterpenos Pentacíclicos , Vías Biosintéticas/genética
11.
Org Biomol Chem ; 21(20): 4309-4318, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-37171256

RESUMEN

In fungi, there is a rare group of natural products harboring the 2,3,3a,9a-tetrahydro-4H-furo[2,3-b]chromene skeleton, represented by xyloketal B, which display a wide range of biological activities and have drawn significant attention. In this work, four new analogues simpliketals A-D (1-4), as well as two other new compounds simplilactones A and B (5 and 6), were isolated from Simplicillium sp. AHK071-01. Their structures were elucidated by extensive NMR spectroscopic methods, 13C NMR calculation, single-crystal X-ray diffraction, and ECD calculation. In addition, five known compounds (7-11) including alboatrin (7) were also obtained. Based on the structural similarity of the above compounds, we inferred that compounds 5, 6, and 8-11 might be biosynthetically related with 1-4 and 7, which allowed us to propose an alternative biosynthetic route to generate the furan-fused chromene skeleton of this class of compounds, instead of a previously presumed polyketide-terpenoid hybrid pathway. Finally, cytotoxicity assays showed that 1-4 exhibited weak inhibitory activity on PANC-1 cells and that 2 and 3 possessed moderate activity against SH-SY5Y cells.


Asunto(s)
Hypocreales , Neuroblastoma , Humanos , Benzopiranos/química , Estructura Molecular , Furanos
12.
Brain ; 145(7): 2602-2616, 2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35104841

RESUMEN

Bi-allelic pathogenic variants in ZBTB11 have been associated with intellectual developmental disorder, autosomal recessive 69 (MRT69; OMIM 618383). We report five patients from three families with novel, bi-allelic variants in ZBTB11. We have expanded the clinical phenotype of MRT69, documenting varied severity of atrophy affecting different brain regions and described combined malonic and methylmalonic aciduria as a biochemical manifestation. As ZBTB11 encodes for a transcriptional regulator, we performeded chromatin immunoprecipitation-sequencing targeting ZBTB11 in fibroblasts from patients and controls. Chromatin immunoprecipitation-sequencing revealed binding of wild-type ZBTB11 to promoters in 238 genes, among which genes encoding proteins involved in mitochondrial functions and RNA processing are over-represented. Mutated ZBTB11 showed reduced binding to 61 of the targeted genes, indicating that the variants act as loss of function. Most of these genes are related to mitochondrial functions. Transcriptome analysis of the patient fibroblasts revealed dysregulation of mitochondrial functions. In addition, we uncovered that reduced binding of the mutated ZBTB11 to ACSF3 leads to decreased ACSF3 transcript level, explaining combined malonic and methylmalonic aciduria. Collectively, these results expand the clinical spectrum of ZBTB11-related neurological disease and give insight into the pathophysiology in which the dysfunctional ZBTB11 affect mitochondrial functions and RNA processing contributing to the neurological and biochemical phenotypes.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos , Errores Innatos del Metabolismo , Malformaciones del Sistema Nervioso , Errores Innatos del Metabolismo de los Aminoácidos/genética , Encéfalo , Humanos , Errores Innatos del Metabolismo/genética
13.
Int J Neurosci ; 133(11): 1224-1232, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34396896

RESUMEN

BACKGROUND: Previous research has revealed that activation or aberrant expression of kinases can lead to tumorigenesis of various cancers, including neuroblastoma (NB). Suppression of kinase expression can reduce drug resistance. We explored the potential role and mechanism of the aurora kinase B (AURKB) gene in the acquisition of carboplatin resistance in NB. METHODS: Immunohistochemistry (IHC) and qRT-PCR were used to explore the AURKB expression in NB patients. Subsequently, we structured Carboplatin-resistant NB cells. The potential biological functions of AURKB in carboplatin resistance were examined through knockdown of AURKB combined with CCK8, flow cytometry, immunohistochemistry, and western blot. Finally, overexpression of AURKB combined with ERK inhibitor (U0126) was carried out to explore the role of downstream signaling pathways. RESULTS: Overexpression of AURKB was closely correlated to poor prognosis in NB patients. In vitro, knockdown of AURKB could lead to a decline in IC50 value and restrain the invasion and the expression of MRP1 and Ki67, while promotes apoptosis in carboplatin-resistant cells (IMR-32-R and SK-N-AS-R). Additionally, AURKB overexpression could potentiate the invasion and the expression of MRP1 and Ki67, while suppresses apoptosis in SK-N-AS-R and IMR-32-R, whereas ERK inhibitor U0126 could reverse the phenomenon caused by AURKB overexpression. CONCLUSION: AURKB overexpression was strongly associated with poor prognosis and carboplatin resistant acquisition. Additionally, suppression of AURKB-ERK axis might be a potential therapy for carboplatin resistance in NB patients.

14.
Sensors (Basel) ; 23(15)2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37571599

RESUMEN

Automatic driving technology refers to equipment such as vehicle-mounted sensors and computers that are used to navigate and control vehicles autonomously by acquiring external environmental information. To achieve automatic driving, vehicles must be able to perceive the surrounding environment and recognize and understand traffic signs, traffic signals, pedestrians, and other traffic participants, as well as accurately plan and control their path. Recognition of traffic signs and signals is an essential part of automatic driving technology, and gesture recognition is a crucial aspect of traffic-signal recognition. This article introduces mm-TPG, a traffic-police gesture recognition system based on a millimeter-wave point cloud. The system uses a 60 GHz frequency-modulated continuous-wave (FMCW) millimeter-wave radar as a sensor to achieve high-precision recognition of traffic-police gestures. Initially, a double-threshold filtering algorithm is used to denoise the millimeter-wave raw data, followed by multi-frame synthesis processing of the generated point cloud data and feature extraction using a ResNet18 network. Finally, gated recurrent units are used for classification to enable the recognition of different traffic-police gestures. Experimental results demonstrate that the mm-TPG system has high accuracy and robustness and can effectively recognize traffic-police gestures in complex environments such as varying lighting and weather conditions, providing strong support for traffic safety.

15.
J Asian Nat Prod Res ; 25(10): 957-967, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36729489

RESUMEN

19-Hydroxybrevianamide M (1) and 6 R-methoxybrevianamide V (2), two new alkaloids, were isolated from an extract of the endophytic fungus Aspergillus sp. JNU18HC0517J, together with six known analogues (3- 8). Their structures were elucidated by extensive spectroscopic analyses, NMR calculations, and ECD calculations. 6 R-methoxybrevianamide V (2) was the first L-proline indole DKP alkaloid with substitution at C-6 on the proline ring. Furthermore, the cytotoxities and antimicrobial activities of these isolated compounds were also evaluated. Compound 8 exhibited moderate antibacterial activity against Staphylococcus aureus 209 P with a minimal inhibitory concentration (MIC) value of 16 µg/ml.[Figure: see text].


Asunto(s)
Alcaloides , Aspergillus , Estructura Molecular , Aspergillus/química , Alcaloides/química , Hongos , Alcaloides Indólicos/química , Antibacterianos/química , Pruebas de Sensibilidad Microbiana
16.
Am J Med Genet A ; 188(5): 1464-1475, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35080095

RESUMEN

Craniosynostosis (CS) is a common congenital anomaly defined by premature fusion of one or more cranial sutures. Syndromic CS involves additional organ anomalies or neurocognitive deficits and accounts for 25%-30% of the cases. In a recent population-based study by our group, 84% of the syndromic CS cases had a genetically verified diagnosis after targeted analyses. A number of different genetic causes were detected, confirming that syndromic CS is highly heterogeneous. In this study, we performed whole-exome sequencing of 10 children and parents from the same cohort where previous genetic results were negative. We detected pathogenic, or likely pathogenic, variants in four additional genes (NFIA, EXTL3, POLR2A, and FOXP2) associated with rare conditions. In two of these (POLR2A and FOXP2), CS has not previously been reported. We further detected a rare predicted damaging variant in SH3BP4, which has not previously been related to human disease. All findings were clustered in genes involved in the pathways of osteogenesis and suture patency. We conclude that whole-exome sequencing expands the list of genes associated with syndromic CS, and provides new candidate genes in osteogenic signaling pathways.


Asunto(s)
Craneosinostosis , Osteogénesis , Proteínas Adaptadoras Transductoras de Señales/genética , Niño , Suturas Craneales , Craneosinostosis/diagnóstico , Craneosinostosis/genética , Humanos , Transducción de Señal/genética , Secuenciación del Exoma/métodos
17.
Langmuir ; 38(13): 4111-4120, 2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35312331

RESUMEN

Self-driven droplet transport along an open gradient surface is increasingly becoming popular for various microfluidics applications. In this work, a gradient copper oxide layer is formed on a copper sheet (as a bipolar electrode, BPE) in a KOH solution by bipolar electrochemistry. The deposits at different positions present a rich variety of colors, compositions, and microstructures along the longitudinal axis of the BPE. More than half the length of the anodic pole is covered by a Cu(OH)2/CuO composite layer of several micrometers thick, which is composed of dense micropillars with a decreasing spacing gradient to the anodic direction. The micropillar arrays are superhydrophilic, and after modified with 1-dodecanethiol, the tops of the dense micropillars constitute a hydrophobic and microscopically discontinuous surface with a wettability gradient. On such a gradient surface water droplets can move spontaneously to more hydrophilic direction at a velocity of about 16 mm s-1. The superhydrophobicity of the modified micropillar arrays is discussed through a comparison with the wax tubules on a lotus leaf. Theoretical analysis of the driving force reveals that the concave surface effect of water at the spacings between the micropillars is the critical factor for driving the rolling motion of the droplets along the gradient micropillar arrays.

18.
Biometrics ; 78(2): 679-690, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33528028

RESUMEN

With the increasing availability of data in the public domain, there has been a growing interest in exploiting information from external sources to improve the analysis of smaller scale studies. An emerging challenge in the era of big data is that the subject-level data are high dimensional, but the external information is at an aggregate level and of a lower dimension. Moreover, heterogeneity and uncertainty in the auxiliary information are often not accounted for in information synthesis. In this paper, we propose a unified framework to summarize various forms of aggregated information via estimating equations and develop a penalized empirical likelihood approach to incorporate such information in logistic regression. When the homogeneity assumption is violated, we extend the method to account for population heterogeneity among different sources of information. When the uncertainty in the external information is not negligible, we propose a variance estimator adjusting for the uncertainty. The proposed estimators are asymptotically more efficient than the conventional penalized maximum likelihood estimator and enjoy the oracle property even with a diverging number of predictors. Simulation studies show that the proposed approaches yield higher accuracy in variable selection compared with competitors. We illustrate the proposed methodologies with a pediatric kidney transplant study.


Asunto(s)
Proyectos de Investigación , Niño , Simulación por Computador , Humanos , Funciones de Verosimilitud
19.
J Cardiovasc Pharmacol ; 80(6): 852-860, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36027600

RESUMEN

ABSTRACT: Vascular calcification (VC) occurs via an active cell-mediated process, which involves osteogenic differentiation, apoptosis, and phenotypic transformation of vascular smooth muscle cells (VSMCs). As a member of the transforming growth factor-ß family, growth differentiation factor 11 (GDF11) can inhibit apoptosis and osteogenic differentiation and maintain the stability of atherosclerotic plaques. In this study, coronary artery calcium score (CACS) of participants with GDF11 measurements was measured using computed tomography angiography and was scored according to the Agatston score. ß-glycerophosphate (10 mM), dexamethasone (100 nM), and l -ascorbic acid (50 µg/mL) [osteogenic medium (OM)] were used to induce calcification of human aortic smooth muscle cells. We found that CACS was negatively correlated with serum GDF11 levels in patients and GDF11 was a strong predictor of elevated CACS (OR = 0.967, 95% CI: 0.945-0.991; P = 0.006), followed by age (OR = 1.151, 95% CI: 1.029-1.286; P = 0.014), triglycerides (OR = 4.743, 95% CI: 1.170-19.236; P = 0.029), C-reactive protein (OR = 1.230, 95% CI: 1.010-1.498; P = 0.04), and hypertension (OR = 7.264, 95% CI: 1.099-48.002; P = 0.04). Furthermore, exogenous GDF11 inhibited OM-induced calcification by inhibiting osteogenic differentiation, the phenotypic transformation and apoptosis of human aortic smooth muscle cells. Our study demonstrates that GDF11 plays a crucial role in reducing vascular calcification and serves as a potential intervention target to vascular calcification.


Asunto(s)
Osteogénesis , Calcificación Vascular , Humanos , Factores Protectores , Factores de Diferenciación de Crecimiento , Calcificación Vascular/diagnóstico por imagen , Proteínas Morfogenéticas Óseas
20.
J Nat Prod ; 85(10): 2312-2331, 2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36137221

RESUMEN

Twenty new malabaricane triterpenoids, astramalabaricosides A-T (1-20), were isolated from the roots of Astragalus membranaceus var. mongholicus (Astragali Radix). Their structures were determined by spectroscopic analysis, and the use of the circular dichroism exciton chirality method, quantum chemical calculations, and chemical methods. Malabaricane triterpenoids, an unusual group with the 6-6-5-tricyclic core, are distributed in plants (e.g., Simaroubaceae, Polypodiaceae, and Fabaceae), a marine sponge, and fungi, and their number obtained to date is limited. Compounds 1-20 were characterized as glycosides with a highly oxygenated side chain, and 13-20 were the first cyclic carbonate derivatives among the malabaricane triterpenoids. The stereocluster formed from the continuous hydroxylated chiral carbons in each highly oxygenated side chain and the 6-6-5-tricyclic core system were entirely segregated, and the independent identification of their stereoconfigurations required considerable effort. The migratory inhibitory and antiproliferative activities of 1-20 were evaluated by wound-healing and cell-viability assays, respectively. Most compounds showed significant migratory inhibitory activity, and a preliminary structure-activity relationship was developed. Malabaricane triterpenoids are being reported in the genus Astragalus for the first time.


Asunto(s)
Planta del Astrágalo , Triterpenos , Astragalus propinquus/química , Triterpenos/farmacología , Triterpenos/análisis , Raíces de Plantas/química
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