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1.
Nature ; 604(7907): 771-778, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35418677

RESUMEN

Adhesion G protein-coupled receptors (aGPCRs) constitute an evolutionarily ancient family of receptors that often undergo autoproteolysis to produce α and ß subunits1-3. A tethered agonism mediated by the 'Stachel sequence' of the ß subunit has been proposed to have central roles in aGPCR activation4-6. Here we present three cryo-electron microscopy structures of aGPCRs coupled to the Gs heterotrimer. Two of these aGPCRs are activated by tethered Stachel sequences-the ADGRG2-ß-Gs complex and the ADGRG4-ß-Gs complex (in which ß indicates the ß subunit of the aGPCR)-and the other is the full-length ADGRG2 in complex with the exogenous ADGRG2 Stachel-sequence-derived peptide agonist IP15 (ADGRG2(FL)-IP15-Gs). The Stachel sequences of both ADGRG2-ß and ADGRG4-ß assume a U shape and insert deeply into the seven-transmembrane bundles. Constituting the FXφφφXφ motif (in which φ represents a hydrophobic residue), five residues of ADGRG2-ß or ADGRG4-ß extend like fingers to mediate binding to the seven-transmembrane domain and activation of the receptor. The structure of the ADGRG2(FL)-IP15-Gs complex reveals the structural basis for the improved binding affinity of IP15 compared with VPM-p15 and indicates that rational design of peptidic agonists could be achieved by exploiting aGPCR-ß structures. By converting the 'finger residues' to acidic residues, we develop a method to generate peptidic antagonists towards several aGPCRs. Collectively, our study provides structural and biochemical insights into the tethered activation mechanism of aGPCRs.


Asunto(s)
Péptidos , Receptores Acoplados a Proteínas G , Microscopía por Crioelectrón , Humanos , Péptidos/metabolismo , Dominios Proteicos , Receptores Acoplados a Proteínas G/metabolismo
2.
Nature ; 589(7843): 620-626, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33408414

RESUMEN

Adhesion G-protein-coupled receptors (GPCRs) are a major family of GPCRs, but limited knowledge of their ligand regulation or structure is available1-3. Here we report that glucocorticoid stress hormones activate adhesion G-protein-coupled receptor G3 (ADGRG3; also known as GPR97)4-6, a prototypical adhesion GPCR. The cryo-electron microscopy structures of GPR97-Go complexes bound to the anti-inflammatory drug beclomethasone or the steroid hormone cortisol revealed that glucocorticoids bind to a pocket within the transmembrane domain. The steroidal core of glucocorticoids is packed against the 'toggle switch' residue W6.53, which senses the binding of a ligand and induces activation of the receptor. Active GPR97 uses a quaternary core and HLY motif to fasten the seven-transmembrane bundle and to mediate G protein coupling. The cytoplasmic side of GPR97 has an open cavity, where all three intracellular loops interact with the Go protein, contributing to the high basal activity of GRP97. Palmitoylation at the cytosolic tail of the Go protein was found to be essential for efficient engagement with GPR97 but is not observed in other solved GPCR complex structures. Our work provides a structural basis for ligand binding to the seven-transmembrane domain of an adhesion GPCR and subsequent G protein coupling.


Asunto(s)
Microscopía por Crioelectrón , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/química , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Glucocorticoides/química , Glucocorticoides/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/ultraestructura , Sitios de Unión , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/ultraestructura , Humanos , Ligandos , Lipoilación , Modelos Moleculares , Unión Proteica , Receptores Acoplados a Proteínas G/metabolismo
3.
Nat Chem Biol ; 20(4): 484-492, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37945893

RESUMEN

GPR101 is an orphan G protein-coupled receptor actively participating in energy homeostasis. Here we report the cryo-electron microscopy structure of GPR101 constitutively coupled to Gs heterotrimer, which reveals unique features of GPR101, including the interaction of extracellular loop 2 within the 7TM bundle, a hydrophobic chain packing-mediated activation mechanism and the structural basis of disease-related mutants. Importantly, a side pocket is identified in GPR101 that facilitates in silico screening to identify four small-molecule agonists, including AA-14. The structure of AA-14-GPR101-Gs provides direct evidence of the AA-14 binding at the side pocket. Functionally, AA-14 partially restores the functions of GH/IGF-1 axis and exhibits several rejuvenating effects in wild-type mice, which are abrogated in Gpr101-deficient mice. In summary, we provide a structural basis for the constitutive activity of GPR101. The structure-facilitated identification of GPR101 agonists and functional analysis suggest that targeting this orphan receptor has rejuvenating potential.


Asunto(s)
Receptores Acoplados a Proteínas G , Ratones , Animales , Microscopía por Crioelectrón , Receptores Acoplados a Proteínas G/metabolismo , Ligandos
4.
Proc Natl Acad Sci U S A ; 120(30): e2216329120, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37478163

RESUMEN

To accomplish concerted physiological reactions, nature has diversified functions of a single hormone at at least two primary levels: 1) Different receptors recognize the same hormone, and 2) different cellular effectors couple to the same hormone-receptor pair [R.P. Xiao, Sci STKE 2001, re15 (2001); L. Hein, J. D. Altman, B.K. Kobilka, Nature 402, 181-184 (1999); Y. Daaka, L. M. Luttrell, R. J. Lefkowitz, Nature 390, 88-91 (1997)]. Not only these questions lie in the heart of hormone actions and receptor signaling but also dissecting mechanisms underlying these questions could offer therapeutic routes for refractory diseases, such as kidney injury (KI) or X-linked nephrogenic diabetes insipidus (NDI). Here, we identified that Gs-biased signaling, but not Gi activation downstream of EP4, showed beneficial effects for both KI and NDI treatments. Notably, by solving Cryo-electron microscope (cryo-EM) structures of EP3-Gi, EP4-Gs, and EP4-Gi in complex with endogenous prostaglandin E2 (PGE2)or two synthetic agonists and comparing with PGE2-EP2-Gs structures, we found that unique primary sequences of prostaglandin E2 receptor (EP) receptors and distinct conformational states of the EP4 ligand pocket govern the Gs/Gi transducer coupling selectivity through different structural propagation paths, especially via TM6 and TM7, to generate selective cytoplasmic structural features. In particular, the orientation of the PGE2 ω-chain and two distinct pockets encompassing agonist L902688 of EP4 were differentiated by their Gs/Gi coupling ability. Further, we identified common and distinct features of cytoplasmic side of EP receptors for Gs/Gi coupling and provide a structural basis for selective and biased agonist design of EP4 with therapeutic potential.


Asunto(s)
Dinoprostona , Transducción de Señal , Dinoprostona/metabolismo , Transducción de Señal/fisiología , Receptores de Prostaglandina/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Hormonas , Subtipo EP4 de Receptores de Prostaglandina E/metabolismo , Subtipo EP2 de Receptores de Prostaglandina E/metabolismo , Subtipo EP3 de Receptores de Prostaglandina E/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(15): e2117004119, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35394864

RESUMEN

GPR126 is a member of the adhesion G protein-coupled receptors (aGPCRs) that is essential for the normal development of diverse tissues, and its mutations are implicated in various pathological processes. Here, through screening 34 steroid hormones and their derivatives for cAMP production, we found that progesterone (P4) and 17-hydroxyprogesterone (17OHP) could specifically activate GPR126 and trigger its downstream Gi signaling by binding to the ligand pocket in the seven-transmembrane domain of the C-terminal fragment of GPR126. A detailed mutagenesis screening according to a computational simulated structure model indicated that K1001ECL2 and F1012ECL2 are key residues that specifically recognize 17OHP but not progesterone. Finally, functional analysis revealed that progesterone-triggered GPR126 activation promoted cell growth in vitro and tumorigenesis in vivo, which involved Gi-SRC pathways in a triple-negative breast cancer model. Collectively, our work identified a membrane receptor for progesterone/17OHP and delineated the mechanisms by which GPR126 participated in potential tumor progression in triple-negative breast cancer, which will enrich our understanding of the functions and working mechanisms of both the aGPCR member GPR126 and the steroid hormone progesterone.


Asunto(s)
Progesterona , Receptores Acoplados a Proteínas G , Receptores de Progesterona , Neoplasias de la Mama Triple Negativas , 17-alfa-Hidroxiprogesterona/metabolismo , Línea Celular Tumoral , Humanos , Progesterona/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Transducción de Señal , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/metabolismo
6.
Prostate ; 84(4): 317-328, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38145367

RESUMEN

BACKGROUND: Prostate leucine zipper (PrLZ) is a prostate-specific protein, and our previous study demonstrated that PrLZ enhances the malignant progression of prostate cancer (Pca). However, the roles of PrLZ in epithelial to mesenchymal transition (EMT) remain unknown. METHODS: Quantitative real-time PCR (qRT-PCR), immunohistochemical (IHC) staining, hematoxylin-eosin (HE) staining, and western blotting were used to analyze the expression of protein and genes level in human PCa cell lines. Invasion assay was used to examine the effect of PrLZ, miR-200a, miR-200b, miR-200c, miR-141, miR-429, miR-205, and ZEB1 on PCa cell line invasion in vitro. Prostate cancer metastasis animal model was designed to assess the effect of PrLZ on PCa cell line invasion in vivo. RESULTS: We proved that high PrLZ expression initiates EMT, which was shown by the downregulation of E-cadherin and upregulation of vimentin in PC-3/PrLZ and ARCaP-E/PrLZ cells. Mechanistic analysis revealed that PrLZ regulates EMT by activating TGF-ß1/p-smad2 signaling and further inhibiting the expression of miR-200 family members, which negatively regulates ZEB1 expression and causes EMT in Pca. Moreover, using two of orthotopic mouse model and tail vein injection of human prostate cancer cells mouse model, we observed that PC-3/PrLZ cells led to the development of distant organ metastases in vivo. CONCLUSIONS: Our results show the mechanism by which PrLZ regulates EMT and metastasis and suggest that PrLZ may be a potential therapeutic target for Pca metastasis.


Asunto(s)
MicroARNs , Neoplasias de la Próstata , Masculino , Animales , Ratones , Humanos , MicroARNs/genética , Factor de Crecimiento Transformador beta1/metabolismo , Próstata/patología , Línea Celular Tumoral , Transición Epitelial-Mesenquimal , Leucina Zippers , Homeobox 1 de Unión a la E-Box con Dedos de Zinc , Neoplasias de la Próstata/patología , Regulación Neoplásica de la Expresión Génica , Movimiento Celular
7.
Lancet ; 402(10395): 41-53, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37331369

RESUMEN

BACKGROUND: There is a paucity of effective systemic therapy options for patients with advanced, chemotherapy-refractory colorectal cancer. We aimed to evaluate the efficacy and safety of fruquintinib, a highly selective and potent oral inhibitor of vascular endothelial growth factor receptors (VEGFRs) 1, 2, and 3, in patients with heavily pretreated metastatic colorectal cancer. METHODS: We conducted an international, randomised, double-blind, placebo-controlled, phase 3 study (FRESCO-2) at 124 hospitals and cancer centres across 14 countries. We included patients aged 18 years or older (≥20 years in Japan) with histologically or cytologically documented metastatic colorectal adenocarcinoma who had received all current standard approved cytotoxic and targeted therapies and progressed on or were intolerant to trifluridine-tipiracil or regorafenib, or both. Eligible patients were randomly assigned (2:1) to receive fruquintinib (5 mg capsule) or matched placebo orally once daily on days 1-21 in 28-day cycles, plus best supportive care. Stratification factors were previous trifluridine-tipiracil or regorafenib, or both, RAS mutation status, and duration of metastatic disease. Patients, investigators, study site personnel, and sponsors, except for selected sponsor pharmacovigilance personnel, were masked to study group assignments. The primary endpoint was overall survival, defined as the time from randomisation to death from any cause. A non-binding futility analysis was done when approximately one-third of the expected overall survival events had occurred. Final analysis occurred after 480 overall survival events. This study is registered with ClinicalTrials.gov, NCT04322539, and EudraCT, 2020-000158-88, and is ongoing but not recruiting. FINDINGS: Between Aug 12, 2020, and Dec 2, 2021, 934 patients were assessed for eligibility and 691 were enrolled and randomly assigned to receive fruquintinib (n=461) or placebo (n=230). Patients had received a median of 4 lines (IQR 3-6) of previous systemic therapy for metastatic disease, and 502 (73%) of 691 patients had received more than 3 lines. Median overall survival was 7·4 months (95% CI 6·7-8·2) in the fruquintinib group versus 4·8 months (4·0-5·8) in the placebo group (hazard ratio 0·66, 95% CI 0·55-0·80; p<0·0001). Grade 3 or worse adverse events occurred in 286 (63%) of 456 patients who received fruquintinib and 116 (50%) of 230 who received placebo; the most common grade 3 or worse adverse events in the fruquintinib group included hypertension (n=62 [14%]), asthenia (n=35 [8%]), and hand-foot syndrome (n=29 [6%]). There was one treatment-related death in each group (intestinal perforation in the fruquintinib group and cardiac arrest in the placebo group). INTERPRETATION: Fruquintinib treatment resulted in a significant and clinically meaningful benefit in overall survival compared with placebo in patients with refractory metastatic colorectal cancer. These data support the use of fruquintinib as a global treatment option for patients with refractory metastatic colorectal cancer. Ongoing analysis of the quality of life data will further establish the clinical benefit of fruquintinib in this patient population. FUNDING: HUTCHMED.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias del Recto , Humanos , Trifluridina/efectos adversos , Factor A de Crecimiento Endotelial Vascular , Calidad de Vida , Neoplasias del Recto/tratamiento farmacológico , Método Doble Ciego , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
8.
Planta ; 260(1): 24, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858226

RESUMEN

MAIN CONCLUSION: The resurrection plant Boea hygrometrica selectively recruits and assembles drought-specific microbial communities across the plant-soil compartments, which may benefit plant growth and fitness under extreme drought conditions. Plant-associated microbes are essential for facilitating plant growth and fitness under drought stress. The resurrection plant Boea hygrometrica in natural habitats with seasonal rainfall can survive rapid desiccation, yet their interaction with microbiomes under drought conditions remains unexplored. This study examined the bacterial and fungal microbiome structure and drought response across plant-soil compartments of B. hygrometrica by high-throughput amplicon sequencing of 16S rRNA gene and internal transcribed spacer. Our results demonstrated that the diversity, composition, and functional profile of the microbial community varied considerably across the plant-soil compartments and were strongly affected by drought stress. Bacterial and fungal diversity was significantly reduced from soil to endosphere and belowground to aboveground compartments. The compartment-specific enrichment of the dominant bacteria phylum Cyanobacteriota and genus Methylorubrum in leaf endosphere, genera Pseudonocardia in rhizosphere soil and Actinoplanes in root endosphere, and fungal phylum Ascomycota in the aboveground compartments and genera Knufia in root endosphere and Cladosporium in leaf endosphere composed part of the core microbiota with corresponding enrichment of beneficial functions for plant growth and fitness. Moreover, the recruitment of dominant microbial genera Sphingosinicella and Plectosphaerella, Ceratobasidiaceae mycorrhizal fungi, and numerous plant growth-promoting bacteria involving nutrient supply and auxin regulation was observed in desiccated B. hygrometrica plants. Our results suggest that the stable assembled drought-specific microbial community of B. hygrometrica may contribute to plant survival under extreme environments and provide valuable microbial resources for the microbe-mediated drought tolerance enhancement in crops.


Asunto(s)
Sequías , Microbiota , Microbiología del Suelo , Microbiota/genética , Estrés Fisiológico , Bacterias/genética , Bacterias/clasificación , Raíces de Plantas/microbiología , Raíces de Plantas/genética , ARN Ribosómico 16S/genética , Hongos/fisiología , Hongos/genética , Rizosfera , Brassicaceae/microbiología , Brassicaceae/genética , Brassicaceae/fisiología , Hojas de la Planta/microbiología , Hojas de la Planta/genética
9.
Nat Chem Biol ; 18(11): 1196-1203, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35982227

RESUMEN

Adhesion G protein-coupled receptors are elusive in terms of their structural information and ligands. Here, we solved the cryogenic-electron microscopy (cryo-EM) structure of apo-ADGRG2, an essential membrane receptor for maintaining male fertility, in complex with a Gs trimer. Whereas the formations of two kinks were determinants of the active state, identification of a potential ligand-binding pocket in ADGRG2 facilitated the screening and identification of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate and deoxycorticosterone as potential ligands of ADGRG2. The cryo-EM structures of DHEA-ADGRG2-Gs provided interaction details for DHEA within the seven transmembrane domains of ADGRG2. Collectively, our data provide a structural basis for the activation and signaling of ADGRG2, as well as characterization of steroid hormones as ADGRG2 ligands, which might be used as useful tools for further functional studies of the orphan ADGRG2.


Asunto(s)
Receptores Acoplados a Proteínas G , Transducción de Señal , Humanos , Masculino , Microscopía por Crioelectrón , Sulfato de Deshidroepiandrosterona , Desoxicorticosterona , Ligandos , Receptores Acoplados a Proteínas G/química
10.
Langmuir ; 40(6): 3168-3180, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38288605

RESUMEN

Hydrogen peroxide (H2O2) is an ideal green product with a broad range of applications, and visible-light-driven photocatalytic H2O2 production is deemed a sustainable and eco-friendly strategy. Herein, various ZnxCd1-xS/MXene photocatalysts with a Schottky junction were prepared for photocatalytic H2O2 production. The obtained Zn0.3Cd0.7S/MXene (ZCM-0.3) hybrid presented the highest photocatalytic H2O2 production rate in pure neutral water of 1160 µmol h-1 g-1, which was further improved to 2178.58 µmol h-1 g-1 in the presence of isopropanol as the sacrificial reagent. The experimental results demonstrated that the sufficient visible-light-harvesting ability and appropriate conduction band potential of the Zn0.3Cd0.7S solid solution, the excellent conductivity and two-electron selectivity of MXene, and the construction of Schottky junctions at the Zn0.3Cd0.7S/MXene interface resulted in the fast transfer and separation of the photogenerated charge carriers and the targeted reduction of oxygen to H2O2. The photocatalytic mechanism for H2O2 production was studied and proposed. Moreover, a simple photo-Fenton system consisting of ZnxCd1-xS/MXene and ferrous ions (Fe2+) was constructed and applied for the degradation of various emerging pollutants, which also performed effectively and exhibited universality across different pollutants. Overall, this study presents a novel and useful strategy to convert solar energy into chemical energy through efficient H2O2 production and provides an effective alternative for the degradation of emerging pollutants.

11.
Crit Rev Food Sci Nutr ; : 1-26, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39002141

RESUMEN

Cancer-related complications pose significant challenges in the management and treatment of patients with malignancies. Several meta-analyses have indicated improving effects of probiotics on cancer complications, while some studies have reported contentious findings. The purpose of the present study was to evaluate the efficacy of probiotics in addressing cancer complications, including diarrhea, mucositis, and infections, following chemotherapy, radiotherapy, and surgery. Relevant studies were searched in the PubMed, Scopus, Embase and Web of Science databases and Google Scholar up to September 2023. All meta-analyses addressing the effects of probiotics on all cancer treatments-induced complications including infection, diarrhea and oral mucositis were included. The pooled results were calculated using a random-effects model. Analyses of subgroups, sensitivity and publication bias were also conducted. The results revealed that the probiotics supplementation was effective on reduction of total cancer complications (OR:0.53; 95% CI: 0.44, 0.62, p < 0.001; I2=79.0%, p < 0.001), total infection rate (OR:0.47; 95%CI: 0.41, 0.52, p < 0.001; I2= 48.8%, p < 0.001); diarrhea (OR:0.50; 95%CI: 0.44, 0.57, p < 0.001; I2=44.4%, p = 0.023) and severe diarrhea (OR: 0.4; 95%CI: 0.27, 0.56, p < 0.001; I2=31.3%, p = 0.178), oral mucositis (OR: 0.76; 95%CI: 0.58, 0.94, p < 0.001; I2=95.5%, p < 0.001) and severe oral mucositis (OR:0.65, 95%CI: 0.58, 0.72 p < 0.001; I2=22.1%, p = 0.274). Multi strain probiotic (OR:0.49; 95%CI: 0.32, 0.65, p < 0.001; I2=90.7%, p < 0.001) were more efficacious than single strain (OR:0.73; 95%CI: 0.66, 0.81, p < 0.001; I2=0.00%, p = 0.786). The findings of the current umbrella meta-analysis provide strong evidence that probiotic supplementation can reduce cancer complications.

12.
J Org Chem ; 89(1): 44-56, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38088910

RESUMEN

In this paper, we present an example of a photoinduced catalyst, halogen-, and base-free TEMPO-mediated interrupted 6π-photocyclization/dehydrogenative aromatization of ortho-biaryl-appended 1,3-dicarbonyl compounds for the preparation of 10-phenanthrenols. The reaction involves rapid photocycloaddition via a 1,2-biradical of 1,3-dicarbonyl compounds, followed by subsequent dehydrogenative aromatization of 1,4-biradical intermediates using TEMPO as the commercially available oxidant rather than trapped by TEMPO to form an alkoxyamine product.

13.
J Org Chem ; 89(1): 474-483, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38096480

RESUMEN

A radical 1,2,4-trifunctional reaction of thiosulfonate to unactivated olefin is achieved by a migration strategy under mild conditions. In this reaction, the more unstable primary free radicals are in situ generated after the migration of heteroaryl groups in the presence of DABCO. This trifunctionalization of unactivated olefins involves two C-S bond formations and one C-C bond formation.

14.
J Org Chem ; 89(12): 8804-8814, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38860924

RESUMEN

1,4-/1,3-Regioselective bifunctionalization of 1,3-enynes with selenosulfonates in water under catalyst-free conditions for the construction of sulfonyl allene and 1,3-disulfonyl-conjugated dienes respectively have been developed. The reactions feature mild reaction conditions in aqueous solution and remarkable regioselectivity controlled by substrates.

15.
Inorg Chem ; 63(2): 1337-1346, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38153815

RESUMEN

Reactions of a chiral and quasi-spherical molecule [1S,4S-2,5-2.2.1-H2dabch]I2 (1) with alkali metal halide MX (M = Na, K, Cs; X = Cl, Br) at room temperature produced a series of organic-inorganic hybrid (OIH) materials [1S,4S-2,5-2.2.1-H2dabch]NaBr3 (2), [1S,4S-2,5-2.2.1-H2dabch]CsCl3·H2O (3) and [1S,4S-2,5-2.2.1-H2dabch]KBr3·H2O (4). The single-crystal X-ray diffraction analysis revealed that the organic-inorganic framework structures comprised of the templating ligand and alkali metal halides (NaBr, CsCl, KBr) displayed dimensions spanning from one-dimensional (1D) to three-dimensional (3D). Moreover, the results of both differential scanning calorimetry (DSC) and dielectric measurements demonstrated that compounds 1-4 displayed reversible, high-temperature phase transitions and noticeable dielectric anomalies. In addition, the temperature-dependent second harmonic generation (SHG) results revealed crystals 1 and 3 can switch from the SHG-ON to the SHG-OFF state, which was proved by the variable-temperature X-ray diffraction. This research aims to streamline the exploration of multifunctional second harmonic generation (SHG) and dielectric materials that have been synthesized using chiral ligands and alkali metals. This will provide researchers with enhanced opportunities to delve further into this specific research domain.

16.
Environ Res ; 257: 119349, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38844029

RESUMEN

Integrated aquaculture wastewater treatment systems (IAWTSs) are widely used in treating aquaculture wastewater with the aeration-microalgae unit serving as an important component. In this study, we artificially constructed an IAWTS and applied two aeration-microalgae methods: ordinary aeration or ozone nanobubbles (ONBs) with microalgae (Nannochloropsis oculata). The impact of N.oculata and ONBs on the removal performance of nutrients and the underlying micro-ecological mechanisms were investigated using 16S rRNA gene amplicon sequencing. The results demonstrated that the combined use of ONBs and N.oculata exhibited superior purification effects with 78.25%, 76.59% and 86.71% removal of CODMn, TN and TP. N.oculata played a pivotal role as the primary element in wastewater purification, while ONBs influenced nutrient dynamics by affecting both N.oculata and bacterial communities. N.oculata actively shaped bacterial communities, with a specific focus on nitrogen and phosphorus cycling in the micro-environment remodeled by ONBs. Rare bacterial communities displayed heightened activity in response to the changes in N.oculata, ONBs, and nutrient levels. These findings provide a novel approach to improve the technological processes the IAWTS, contributing to the advancement of sustainable aquaculture practices by offering valuable insights into wastewater purification efficiency and micro-ecological mechanisms.


Asunto(s)
Acuicultura , Microalgas , Microbiota , Ozono , Eliminación de Residuos Líquidos , Aguas Residuales , Acuicultura/métodos , Aguas Residuales/química , Aguas Residuales/microbiología , Microbiota/efectos de los fármacos , Eliminación de Residuos Líquidos/métodos , Fósforo/metabolismo , Nitrógeno/metabolismo
17.
Environ Res ; 250: 118492, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38373550

RESUMEN

Dioxin-like pollutants (DLPs), such as polychlorinated biphenyl 126 (PCB 126), are synthetic chemicals classified as persistent organic pollutants. They accumulate in adipose tissue and have been linked to cardiometabolic disorders, including fatty liver disease. The toxicity of these compounds is associated with activation of the aryl hydrocarbon receptor (Ahr), leading to the induction of phase I metabolizing enzyme cytochrome P4501a1 (Cyp1a1) and the subsequent production of reactive oxygen species (ROS). Recent research has shown that DLPs can also induce the xenobiotic detoxification enzyme flavin-containing monooxygenase 3 (FMO3), which plays a role in metabolic homeostasis. We hypothesized whether genetic deletion of Fmo3 could protect mice, particularly in the liver, where Fmo3 is most inducible, against PCB 126 toxicity. To test this hypothesis, male C57BL/6 wild-type (WT) mice and Fmo3 knockout (Fmo3 KO) mice were exposed to PCB 126 or vehicle (safflower oil) during a 12-week study, at weeks 2 and 4. Various analyses were performed, including hepatic histology, RNA-sequencing, and quantitation of PCB 126 and F2-isoprostane concentrations. The results showed that PCB 126 exposure caused macro and microvesicular fat deposition in WT mice, but this macrovesicular fatty change was absent in Fmo3 KO mice. Moreover, at the pathway level, the hepatic oxidative stress response was significantly different between the two genotypes, with the induction of specific genes observed only in WT mice. Notably, the most abundant F2-isoprostane, 8-iso-15-keto PGE2, increased in WT mice in response to PCB 126 exposure. The study's findings also demonstrated that hepatic tissue concentrations of PCB 126 were higher in WT mice compared to Fmo3 KO mice. In summary, the absence of FMO3 in mice led to a distinctive response to dioxin-like pollutant exposure in the liver, likely due to alterations in lipid metabolism and storage, underscoring the complex interplay of genetic factors in the response to environmental toxins.


Asunto(s)
Ratones Endogámicos C57BL , Ratones Noqueados , Estrés Oxidativo , Oxigenasas , Bifenilos Policlorados , Animales , Oxigenasas/genética , Oxigenasas/metabolismo , Bifenilos Policlorados/toxicidad , Estrés Oxidativo/efectos de los fármacos , Ratones , Masculino , Hígado/efectos de los fármacos , Hígado/metabolismo , Contaminantes Ambientales/toxicidad
18.
Artículo en Inglés | MEDLINE | ID: mdl-38526751

RESUMEN

Vaccines against SARS-CoV-2 have been recommended across the world, yet no study has investigated whether COVID-19 vaccination influences short-term warfarin anti-coagulation levels. Patients on stable warfarin treatment who received anti-SARS-CoV-2 vaccination were prospectively enrolled and followed up for three months. INR values less than 10 days before vaccination (baseline), 3-5 days (short-term) and 6-14 days (medium-term) after vaccination were recorded as INR0, INR1, and INR2, respectively. The variations of INR values within individuals were compared, and the linear mixed effect model was used to evaluate the variations of INR values at different time points. Logistic regression analysis was performed to determine covariates related to INR variations after COVID-19 vaccination. Vaccination safety was also monitored. There was a significant difference in INR values between INR0 and INR1 (2.15 vs. 2.26, p = 0.003), yet no marked difference was found between INR0 and INR2. The linear mixed effect model also demonstrated that INR variation was significant in short-term but not in medium-term or long-term period after vaccination. Logistic regression analysis showed that no investigated covariates, including age, vaccine dose, genetic polymorphisms of VKORC1 and CYP2C9 etc., were associated with short-term INR variations. Two patients (2.11%) reported gingival hemorrhage in the short-term due to increased INR values. The overall safety of COVID-19 vaccines for patients on warfarin was satisfying. COVID-19 vaccines may significantly influence warfarin anticoagulation levels 3-5 days after vaccination. We recommend patients on warfarin to perform at least one INR monitoring within the first week after COVID-19 vaccination.

19.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34740971

RESUMEN

Inflammation in the epididymis and testis contributes significantly to male infertility. Alternative therapeutic avenues treating epididymitis and orchitis are expected since current therapies using antibiotics have limitations associated to side effects and are commonly ineffective for inflammation due to nonbacterial causes. Here, we demonstrated that type 1 parathyroid hormone receptor (PTH1R) and its endogenous agonists, parathyroid hormone (PTH) and PTH-related protein (PTHrP), were mainly expressed in the Leydig cells of testis as well as epididymal epithelial cells. Screening the secretin family G protein-coupled receptor identified that PTH1R in the epididymis and testis was down-regulated in mumps virus (MuV)- or lipopolysaccharide (LPS)-induced inflammation. Remarkably, activation of PTH1R by abaloparatide (ABL), a Food and Drug Administration-approved treatment for postmenopausal osteoporosis, alleviated MuV- or LPS-induced inflammatory responses in both testis and epididymis and significantly improved sperm functions in both mouse model and human samples. The anti-inflammatory effects of ABL were shown to be regulated mainly through the Gq and ß-arrestin-1 pathway downstream of PTH1R as supported by the application of ABL in Gnaq± and Arrb1-/- mouse models. Taken together, our results identified an important immunoregulatory role for PTH1R signaling in the epididymis and testis. Targeting to PTH1R might have a therapeutic effect for the treatment of epididymitis and orchitis or other inflammatory disease in the male reproductive system.


Asunto(s)
Epididimitis/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Orquitis/metabolismo , Receptor de Hormona Paratiroídea Tipo 1/metabolismo , beta-Arrestina 1/metabolismo , Animales , Infertilidad Masculina/metabolismo , Infertilidad Masculina/virología , Lipopolisacáridos , Masculino , Ratones Endogámicos C57BL , Virus de la Parotiditis
20.
Artículo en Inglés | MEDLINE | ID: mdl-38904619

RESUMEN

Objective: This study specifically investigates the impact of sacubitril/valsartan on cardiac structural remodeling and modulation of blood levels of miRNA-328 and NT-proBNP in patients with coronary heart disease (CHD) complicated by chronic heart failure (CHF). We aim to determine whether sacubitril/valsartan offers advantages over traditional therapies regarding cardiac morphology and molecular biomarkers, thus providing insights into its potential role in managing CHD and CHF. Methods: From January 2020 to January 2023, CHD patients with chronic heart failure were randomized into two groups for this study. Both groups received standard treatments: the control group received valsartan, while the study group received sacubitril/valsartan. Therapeutic outcomes were analyzed, including changes in cardiac structure, function, miRNA-328, and NT-proBNP levels in the blood, along with noting any adverse reactions. Results: The total effective rate in the study group was 86.67%, significantly higher than that in the control group (71.67%) (P < .05). After treatment, both groups exhibited reductions in left atrial anterior and posterior diameter, left ventricular end-diastolic diameter, and left ventricular end-systolic diameter compared to before treatment, with the study group showing lower values than the control group (P < .05). The left ventricular ejection fraction (LVEF) increased in both groups, with the study group showing a higher increase than the control group. Additionally, the end-diastolic volume and end-systolic volume decreased in both groups after treatment, with the study group showing greater decreases than the control group (P < .05). Moreover, both groups exhibited reductions in peripheral blood levels of miRNA-328 and NT-proBNP, with the study group showing greater reductions than the control group (P < .05). There was no significant difference in the incidence of adverse reactions between the study group and the control group during treatment (P > .05). Conclusion: Sacubitril/valsartan significantly improves cardiac function and structure in patients with CHD complicated by CHF, effectively reducing levels of miRNA-328 and NT-proBNP in the blood. It demonstrates safety and high value in clinical applications.

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