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1.
Biochem Biophys Res Commun ; 721: 150109, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38762932

RESUMEN

Wild-type Proteinase K binds to two Ca2+ ions, which play an important role in regulating enzymaticactivity and maintaining protein stability. Therefore, a predetermined concentration of Ca2+ must be added during the use of Proteinase K, which increases its commercial cost. Herein, we addressed this challenge using a computational strategy to engineer a Proteinase K mutant that does not require Ca2+ and exhibits high enzymatic activity and protein stability. In the absence of Ca2+, the best mutant, MT24 (S17W-S176N-D260F), displayed an activity approximately 9.2-fold higher than that of wild-type Proteinase K. It also exhibited excellent protein stability, retaining 56.2 % of its enzymatic activity after storage at 4 °C for 5 days. The residual enzymatic activity was 65-fold higher than that of the wild-type Proteinase K under the same storage conditions. Structural analysis and molecular dynamics simulations suggest that the introduction of new hydrogen bond and π-π stacking at the Ca2+ binding sites due to the mutation may be the reasons for the increased enzymatic activity and stability of MT24.

2.
New Phytol ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769723

RESUMEN

Potato (Solanum tuberosum) is the fourth largest food crop in the world. Late blight, caused by oomycete Phytophthora infestans, is the most devastating disease threatening potato production. Previous research has shown that StRFP1, a potato Arabidopsis Tóxicos en Levadura (ATL) family protein, positively regulates late blight resistance via its E3 ligase activity. However, the underlying mechanism is unknown. Here, we reveal that StRFP1 is associated with the plasma membrane (PM) and undergoes constitutive endocytic trafficking. Its PM localization is essential for inhibiting P. infestans colonization. Through in vivo and in vitro assays, we investigated that StRFP1 interacts with two sugar transporters StSWEET10c and StSWEET11 at the PM. Overexpression (OE) of StSWEET10c or StSWEET11 enhances P. infestans colonization. Both StSWEET10c and StSWEET11 exhibit sucrose transport ability in yeast, and OE of StSWEET10c leads to an increased sucrose content in the apoplastic fluid of potato leaves. StRFP1 ubiquitinates StSWEET10c and StSWEET11 to promote their degradation. We illustrate a novel mechanism by which a potato ATL protein enhances disease resistance by degrading susceptibility (S) factors, such as Sugars Will Eventually be Exported Transporters (SWEETs). This offers a potential strategy for improving disease resistance by utilizing host positive immune regulators to neutralize S factors.

3.
Nanomicro Lett ; 16(1): 190, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698298

RESUMEN

A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells. The control of forming uniform and large-area film and perovskite crystallization is still the main obstacle restricting the efficiency of PSMs. In this work, we adopted a solid-liquid two-step film formation technique, which involved the evaporation of a lead iodide film and blade coating of an organic ammonium halide solution to prepare perovskite films. This method possesses the advantages of integrating vapor deposition and solution methods, which could apply to substrates with different roughness and avoid using toxic solvents to achieve a more uniform, large-area perovskite film. Furthermore, modification of the NiOx/perovskite buried interface and introduction of Urea additives were utilized to reduce interface recombination and regulate perovskite crystallization. As a result, a large-area perovskite film possessing larger grains, fewer pinholes, and reduced defects could be achieved. The inverted PSM with an active area of 61.56 cm2 (10 × 10 cm2 substrate) achieved a champion power conversion efficiency of 20.56% and significantly improved stability. This method suggests an innovative approach to resolving the uniformity issue associated with large-area film fabrication.

4.
Eur J Nutr ; 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38703229

RESUMEN

PURPOSE: The traditional Chinese herbal medicine Suaeda salsa (L.) Pall (S. salsa) with a digesting food effect was taken as the research object, and its chemical composition and action mechanism were explored. METHODS: The chemical constituents of S. salsa were isolated and purified by column chromatography, and their structures were characterized by nuclear magnetic resonance. The food accumulation model in mice was established, and the changes of the aqueous extract of S. salsa in gastric emptying and intestinal propulsion rate, colonic tissue lesions, serum brain-gut peptide hormone, colonic tissue protein expression, and gut microbiota structure were compared. RESULTS: Ten compounds were isolated from S. salsa named as naringenin (1), hesperetin (2), baicalein (3), luteolin (4), isorhamnetin (5), taxifolin (6), isorhamnetin-3-O-ß-D-glucoside (7), luteolin-3'-D-glucuronide (8), luteolin-7-O-ß-D-glucuronide (9), and quercetin-3-O-ß-D-glucuronide (10), respectively. The aqueous extract of S. salsa can improve the pathological changes of the mice colon and intestinal peristalsis by increasing the rate of gastric emptying and intestinal propulsion. By adjusting the levels of 5-HT, CCK, NT, SS, VIP, GT-17, CHE, MTL, and ghrelin, it can upregulate the levels of c-kit, SCF, and GHRL protein, and restore the imbalanced structure of gut microbiota, further achieve the purpose of treating the syndrome of indigestion. The effect is better with the increase of dose. CONCLUSION: S. salsa has a certain therapeutic effect on mice with the syndrome of indigestion. From the perspective of "brain-gut-gut microbiota", the mechanism of digestion and accumulation of S. salsa was discussed for the first time, which provided an experimental basis for further exploring the material basis of S. salsa.

6.
Ren Fail ; 46(1): 2332492, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38584135

RESUMEN

Acute kidney injury (AKI) is associated with a high mortality rate. Pathologically, renal ischemia/reperfusion injury (RIRI) is one of the primary causes of AKI, and hypoxia-inducible factor (HIF)-1α may play a defensive role in RIRI. This study assessed the role of hypoxia-inducible factor 1α (HIF-1α)-mediated mitophagy in protection against RIRI in vitro and in vivo. The human tubular cell line HK-2 was used to assess hypoxia/reoxygenation (H/R)-induced mitophagy through different in vitro assays, including western blotting, immunofluorescence staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), and reactive oxygen species (ROS) measurement. Additionally, a rat RIRI model was established for evaluation by renal histopathology, renal Doppler ultrasound, and transmission electron microscopy to confirm the in vitro data. The selective HIF-1α inhibitor LW6 reduced H/R-induced mitophagy but increased H/R-induced apoptosis and ROS production. Moreover, H/R treatment enhanced expression of the FUN14 domain-containing 1 (FUNDC1) protein. Additionally, FUNDC1 overexpression reversed the effects of LW6 on the altered expression of light chain 3 (LC3) BII and voltage-dependent anion channels as well as blocked the effects of HIF-1α inhibition in cells. Pretreatment of the rat RIRI model with roxadustat, a novel oral HIF-1α inhibitor, led to decreased renal injury and apoptosis in vivo. In conclusion, the HIF-1α/FUNDC1 signaling pathway mediates H/R-promoted renal tubular cell mitophagy, whereas inhibition of this signaling pathway protects cells from mitophagy, thus aggravating apoptosis, and ROS production. Accordingly, roxadustat may protect against RIRI-related AKI.


Asunto(s)
Lesión Renal Aguda , Daño por Reperfusión , Animales , Humanos , Ratas , Lesión Renal Aguda/etiología , Lesión Renal Aguda/prevención & control , Lesión Renal Aguda/metabolismo , Apoptosis , Hipoxia/metabolismo , Hipoxia/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Isquemia , Riñón/patología , Proteínas de la Membrana/metabolismo , Proteínas Mitocondriales , Mitofagia , Especies Reactivas de Oxígeno/metabolismo , Daño por Reperfusión/metabolismo , Transducción de Señal
7.
Inorg Chem ; 63(15): 6909-6921, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38564449

RESUMEN

The coprecipitation of iron (Fe) and phosphorus (P) in natural environments limits their bioavailability. Plant root-secreted organic acids can dissolve Fe-P precipitates, but the molecular mechanism underlying mobilizing biogenic elements from highly insoluble inorganic minerals remains poorly understood. Here, we investigated vivianite (Fe3(PO4)2·8H2O) dissolution by organic acids (oxalic acid (OA), citric acid (CA), and 2'-dehydroxymugineic acid (DMA)) at three different pH values (4.0, 6.0, and 8.0). With increasing pH, the vivianite dissolution efficiency by OA and CA was decreased while that by DMA was increased, indicating various dissolution mechanisms of different organic acids. Under acidic conditions, weak ligand OA (HC2O4- > C2O42- at pH 4.0 and C2O42- at pH 6.0) dissolved vivianite through the H+ effect to form irregular pits, but under alkaline condition (pH 8.0), the completely deprotonated OA was insufficient to dissolve vivianite. At pH 4.0, CA (H2Cit- > HCit2- > H3Cit) dissolved vivianite to form irregular pits through a proton-promoted mechanism, while at pH 6.0 (HCit2- > Cit3-) and pH 8.0 (Cit3-), CA dissolved vivianite to form near-rhombohedral pits through a ligand-promoted mechanism. At three pH values ((H0)DMA3- > (H1)DMA2- at pH 4.0, (H0)DMA3- at pH 6.0, and (H0)DMA3- and one deprotonated imino at pH 8.0), strong ligand DMA dissolved vivianite to form near-rhombohedral pits via ligand-promoted mechanisms. Raman spectroscopy showed that the deprotonated carboxyl groups (COO-) and imino groups were bound to Fe on the vivianite (010) face. The surface free energy of vivianite coated with OA decreased from 29.32 mJ m-2 to 24.23 mJ m-2 and then to 13.47 mJ m-2 with increasing pH, and that coated with CA resulted in a similar pH-dependent vivianite surface free-energy decrease while that coated with DMA increased the vivianite surface free energy from 31.92 mJ m-2 to 39.26 mJ m-2 and then to 49.93 mJ m-2. Density functional theory (DFT)-based calculations confirmed these findings. Our findings provide insight into the mechanism by which organic acids dissolved vivianite through proton and ligand effects.

8.
J Pharm Anal ; 14(3): 401-415, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38618249

RESUMEN

Activation of nuclear factor erythroid 2-related factor 2 (Nrf2) by Kelch-like ECH-associated protein 1 (Keap1) alkylation plays a central role in anti-inflammatory therapy. However, activators of Nrf2 through alkylation of Keap1-Kelch domain have not been identified. Deoxynyboquinone (DNQ) is a natural small molecule discovered from marine actinomycetes. The current study was designed to investigate the anti-inflammatory effects and molecular mechanisms of DNQ via alkylation of Keap1. DNQ exhibited significant anti-inflammatory properties both in vitro and in vivo. The pharmacophore responsible for the anti-inflammatory properties of DNQ was determined to be the α, ß-unsaturated amides moieties by a chemical reaction between DNQ and N-acetylcysteine. DNQ exerted anti-inflammatory effects through activation of Nrf2/ARE pathway. Keap1 was demonstrated to be the direct target of DNQ and bound with DNQ through conjugate addition reaction involving alkylation. The specific alkylation site of DNQ on Keap1 for Nrf2 activation was elucidated with a synthesized probe in conjunction with liquid chromatography-tandem mass spectrometry. DNQ triggered the ubiquitination and subsequent degradation of Keap1 by alkylation of the cysteine residue 489 (Cys489) on Keap1-Kelch domain, ultimately enabling the activation of Nrf2. Our findings revealed that DNQ exhibited potent anti-inflammatory capacity through α, ß-unsaturated amides moieties active group which specifically activated Nrf2 signal pathway via alkylation/ubiquitination of Keap1-Kelch domain, suggesting the potential values of targeting Cys489 on Keap1-Kelch domain by DNQ-like small molecules in inflammatory therapies.

9.
ACS Synth Biol ; 13(5): 1562-1571, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38679882

RESUMEN

Respirantins are 18-membered antimycin-type depsipeptides produced by Streptomyces sp. and Kitasatospora sp. These compounds have shown extraordinary anticancer activities against a panel of cancer cell lines with nanomolar levels of IC50 values. However, further investigation has been impeded by the low titers of the natural producers and the challenging chemical synthesis due to their structural complexity. The biosynthetic gene cluster (BGC) of respirantin was previously proposed based on a bioinformatic comparison of the four members of antimycin-type depsipeptides. In this study, we report the first successful reconstitution of respirantin in Streptomyces albus using a synthetic BGC. This heterologous system serves as an accessible platform for the production and diversification of respirantins. Through polyketide synthase pathway engineering, biocatalysis, and chemical derivatization, we generated nine respirantin compounds, including six new derivatives. Cytotoxicity screening against human MCF-7 and Hela cancer cell lines revealed a unique biphasic dose-response profile of respirantin. Furthermore, a structure-activity relationship study has elucidated the essential functional groups that contribute to its remarkable cytotoxicity. This work paves the way for respirantin-based anticancer drug discovery and development.


Asunto(s)
Antimicina A , Antineoplásicos , Depsipéptidos , Familia de Multigenes , Streptomyces , Humanos , Streptomyces/metabolismo , Streptomyces/genética , Depsipéptidos/farmacología , Depsipéptidos/química , Depsipéptidos/biosíntesis , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , Antineoplásicos/química , Células HeLa , Antimicina A/análogos & derivados , Antimicina A/farmacología , Antimicina A/metabolismo , Células MCF-7 , Sintasas Poliquetidas/metabolismo , Sintasas Poliquetidas/genética , Vías Biosintéticas/genética , Relación Estructura-Actividad
10.
Int J Surg ; 110(4): 1896-1903, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38668654

RESUMEN

BACKGROUND: It is unclear whether laparoscopic hepatectomy (LH) for hepatolithiasis confers better clinical benefit and lower hospital costs than open hepatectomy (OH). This study aim to evaluate the clinical and economic value of LH versus OH. METHODS: Patients undergoing OH or LH for primary hepatolithiasis at Yijishan Hospital of Wannan Medical College between 2015 and 2022 were divided into OH group and LH group. Propensity score matching (PSM) was used to balance the baseline data. Deviation-based cost modelling and weighted average median cost (WAMC) were used to assess and compare the economic value. RESULTS: A total of 853 patients were identified. After exclusions, 403 patients with primary hepatolithiasis underwent anatomical hepatectomy (OH n=143; LH n=260). PSM resulted in 2 groups of 100 patients each. Although LH required a longer median operation duration compared with OH (285.0 versus 240.0 min, respectively, P<0.001), LH patients had fewer wound infections, fewer pre-discharge overall complications (26 versus 43%, respectively, P=0.009), and shorter median postoperative hospital stays (8.0 versus 12.0 days, respectively, P<0.001). No differences were found in blood loss, major complications, stone clearance, and mortality between the two matched groups. However, the median overall hospital cost of LH was significantly higher than that of OH (CNY¥52,196.1 versus 45,349.5, respectively, P=0.007). Although LH patients had shorter median postoperative hospital stays and fewer complications than OH patients, the WAMC was still higher for the LH group than for the OH group with an increase of CNY¥9,755.2 per patient undergoing LH. CONCLUSION: The overall clinical benefit of LH for hepatolithiasis is comparable or even superior to that of OH, but with an economic disadvantage. There is a need to effectively reduce the hospital costs of LH and the gap between costs and diagnosis-related group reimbursement to promote its adoption.


Asunto(s)
Hepatectomía , Laparoscopía , Puntaje de Propensión , Humanos , Hepatectomía/economía , Hepatectomía/métodos , Femenino , Masculino , Laparoscopía/economía , Laparoscopía/métodos , Persona de Mediana Edad , Adulto , Estudios Retrospectivos , Hepatopatías/cirugía , Hepatopatías/economía , Estudios de Cohortes , Anciano , Litiasis/cirugía , Litiasis/economía , Tiempo de Internación/economía , Tiempo de Internación/estadística & datos numéricos , Complicaciones Posoperatorias/economía , Resultado del Tratamiento
11.
Sci Total Environ ; 929: 172331, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38608879

RESUMEN

The iron oxyhydroxides of iron plaque on the surface of rice root are crucial for the uptake of nutrition elements, especially phosphorus (P), but the effects of iron oxyhydroxides of iron plaque on the accumulation and uptake of P remain largely unknown. In this study, we investigated the regulatory mechanism of iron plaque on P uptake in rice via hydroponics of whole plant and simulation of iron oxyhydroxides-coated suspension cells in rice. The hydroponic experiment results showed that the presence of iron plaque increased the P content in rice shoots. The simulation experiment results further confirmed that after iron plaque coating, the P contents in the whole cell and on the cell wall were significantly increased from 5.16 mg/g and 2.73 mg/g to 8.85 mg/g and 5.27 mg/g, respectively. In addition, our data also showed that iron plaque coating led to an increase in cell surface potentials from -380 ± 40 mV to -200 ± 30 mV, thus promoting the adsorption of more P. Taken together, this study demonstrated that the iron plaque coating increased the surface potential of the cells, thus enhancing cellular P enrichment, eventually promoting P efficient adsorption in rice. Deciphering these regulatory mechanisms provide an insight into P biogeochemical cycling at the soil-plant interface and offer theoretical basis and practical references for the improvement of P bioavailability in rice production.


Asunto(s)
Hierro , Oryza , Fósforo , Raíces de Plantas , Oryza/metabolismo , Fósforo/metabolismo , Raíces de Plantas/metabolismo , Hierro/metabolismo , Hidroponía
12.
Adv Mater ; : e2400347, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38573812

RESUMEN

Suppressing trap-assisted nonradiative losses through passivators is a prerequisite for efficient perovskite light-emitting diodes (PeLEDs). However, the complex bonding between passivators and perovskites severely suppresses the passivation process, which still lacks comprehensive understanding. Herein, the number, category, and degree of bonds between different functional groups and the perovskite are quantitatively assessed to study the passivation dynamics. Functional groups with high electrostatic potential and large steric hindrance prioritize strong bonding with organic cations and halides on the perfect surface, leading to suppressed coordination with bulky defects. By modulating the binding priorities and coordination capacity, hindrance from the intense interaction with perfect perovskite is significantly reduced, leading to a more direct passivation process. Consequently, the near-infrared PeLED without external light out-coupling demonstrates a record external quantum efficiency of 24.3% at a current density of 42 mA cm-2. In addition, the device exhibits a record-level-cycle ON/OFF switching of 20 000 and ultralong half-lifetime of 1126.3 h under 5 mA cm-2. An in-depth understanding of the passivators can offer new insights into the development of high-performance PeLEDs.

13.
Oncogene ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671157

RESUMEN

The long-term maintenance of leukaemia stem cells (LSCs) is responsible for the high degree of malignancy in MLL (mixed-lineage leukaemia) rearranged acute myeloid leukaemia (AML). The DNA damage response (DDR) and DOT1L/H3K79me pathways are required to maintain LSCs in MLLr-AML, but little is known about their interplay. This study revealed that the DDR enzyme ATM regulates the maintenance of LSCs in MLLr-AML with a sequential protein-posttranslational-modification manner via CBP-DOT1L. We identified the phosphorylation of CBP by ATM, which confers the stability of CBP by preventing its proteasomal degradation, and characterised the acetylation of DOT1L by CBP, which mediates the high level of H3K79me2 for the expression of leukaemia genes in MLLr-AML. In addition, we revealed that the regulation of CBP-DOT1L axis in MLLr-AML by ATM was independent of DNA damage activation. Our findings provide insight into the signalling pathways involoved in MLLr-AML and broaden the understanding of the role of DDR enzymes beyond processing DNA damage, as well as identigying them as potent cancer targets.

14.
Phys Med Biol ; 69(9)2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38527368

RESUMEN

Transbronchial microwave ablation (MWA) with flexible antennas has gradually become an attractive alternative to percutaneous MWA for lung cancer due to its characteristic of non-invasiveness. However, flexible antennas for the precision ablation of lung tumors that are adjacent to critical bronchial structures are still not available. In this study, a non-invasive flexible directional (FD) antenna for early stage central lung tumors surrounding the bronchia was proposed. A comprehensive numerical MWA model with the FD antenna was developed in a real human-sized left lung model. The structure of the antenna and the treatment protocol were optimized by a generic algorithm for the precision ablation of two cases of early stage central lung cancer (i.e. spherical-like and ellipsoidal tumors). The electromagnetic efficiency of the optimized antenna was also improved by implementing an optimizedπ-matching network for impedance matching. The results indicate that the electromagnetic energy of MWA can be restricted to a particular area for precision ablation of specific lung tumors using the FD antenna. This study contributes to the field of lung cancer management with MWA.


Asunto(s)
Técnicas de Ablación , Neoplasias Pulmonares , Microondas , Microondas/uso terapéutico , Neoplasias Pulmonares/cirugía , Neoplasias Pulmonares/radioterapia , Humanos , Técnicas de Ablación/métodos , Técnicas de Ablación/instrumentación
15.
Surgery ; 175(6): 1539-1546, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38508920

RESUMEN

BACKGROUND: Ischemia-reperfusion injury is a common problem in liver surgery and transplantation. Although ischemia-reperfusion injury is known to be more pronounced in fatty livers, the underlying mechanisms for this difference remain poorly understood. We hypothesized that ferroptosis plays a significant role in fatty liver ischemia-reperfusion injury due to increased lipid peroxidation in the presence of stored iron in the fatty liver. To test this hypothesis, the ferroptosis pathway was evaluated in a murine fatty liver ischemia-reperfusion injury model. METHODS: C57BL6 mice were fed with a normal diet or a high fat, high sucrose diet for 12 weeks. At 22 weeks of age, liver ischemia-reperfusion injury was induced through partial (70%) hepatic pedicle clamping for 60 minutes, followed by 24 hours of reperfusion before tissue harvest. Acyl-coenzyme A synthetase long-chain family member 4 and 4-hydroxynonenal were quantified in the liver tissues. In separate experiments, liproxstatin-1 or vehicle control was administered for 7 consecutive days before liver ischemia-reperfusion injury. RESULTS: Exacerbated ischemia-reperfusion injury was observed in the livers of high fat, high sucrose diet fed mice. High fat, high sucrose diet + ischemia-reperfusion injury (HDF+IRI) livers had a significantly greater abundance of acyl-coenzyme A synthetase long-chain family member 4 and 4-hydroxynonenal compared with normal diet + ischemia-reperfusion injury (ND+IRI) livers or sham fatty livers, which indicated an increase of ferroptosis. HFD fed animals receiving liproxstatin-1 injections had a significant reduction in serum aspartate transaminase and alanine transaminase after ischemia-reperfusion injury, consistent with attenuation of ischemia-reperfusion injury in the liver. CONCLUSION: Ferroptosis plays a significant role in ischemia-reperfusion injury in fatty livers. Inhibiting ferroptotic pathways in the liver may serve as a novel therapeutic strategy to protect the fatty liver in the setting of ischemia-reperfusion injury.


Asunto(s)
Ferroptosis , Peroxidación de Lípido , Hígado , Ratones Endogámicos C57BL , Daño por Reperfusión , Animales , Daño por Reperfusión/metabolismo , Daño por Reperfusión/etiología , Daño por Reperfusión/patología , Ratones , Masculino , Hígado/metabolismo , Hígado/irrigación sanguínea , Hígado/patología , Hígado Graso/metabolismo , Hígado Graso/etiología , Hígado Graso/patología , Modelos Animales de Enfermedad , Aldehídos/metabolismo , Coenzima A Ligasas/metabolismo , Dieta Alta en Grasa/efectos adversos , Quinoxalinas , Compuestos de Espiro
16.
Angew Chem Int Ed Engl ; 63(22): e202403365, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38454191

RESUMEN

Meroterpenoids of the ochraceopones family featuring a linear tetracyclic scaffold exhibit exceptional antiviral and anti-inflammatory activities. The biosynthetic pathway and chemical logic to generate this linear tetracycle, however, remain unknown. In this study, we identified and characterized all biosynthetic enzymes to afford ochraceopones and elucidated the complete biosynthetic pathway. We demonstrated that the linear tetracyclic scaffold of ochraceopones was derived from an angular tetracyclic precursor. A multifunctional cytochrome P450 OchH was validated to catalyze the free-radical-initiated carbon-carbon bond cleavage of the angular tetracycle. Then, a new carbon-carbon bond was verified to be constructed using a new aldolase OchL, which catalyzes an intramolecular aldol reaction to form the linear tetracycle. This carbon-carbon bond fragmentation and aldol reaction cascade features an unprecedented strategy for converting a common angular tetracycle to a distinctive linear tetracyclic scaffold in meroterpenoid biosynthesis.


Asunto(s)
Carbono , Sistema Enzimático del Citocromo P-450 , Carbono/química , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/química , Estructura Molecular , Terpenos/química , Terpenos/metabolismo , Aldehídos/química , Aldehídos/metabolismo , Biocatálisis
17.
J Chem Neuroanat ; 137: 102413, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38492895

RESUMEN

Chronic pain is often accompanied by tissue damage and pain hypersensitivity. It easily relapses and is challenging to cure, which seriously affects the patients' quality of life and is an urgent problem to be solved. Current treatment methods primarily rely on morphine drugs, which do not address the underlying nerve injury and may cause adverse reactions. Therefore, in recent years, scientists have shifted their focus from chronic pain treatment to cell transplantation. This review describes the classification and mechanism of chronic pain through the introduction of the characteristics of olfactory ensheathing cells (OECs), an in-depth discussion of special glial cells through the phagocytosis of nerve debris, receptor-ligand interactions, providing nutrition, and other inhibition of neuroinflammation, and ultimately supporting axon regeneration and mitigation of chronic pain. This review summarizes the potential and limitations of OECs for treating chronic pain by objectively analyzing relevant clinical trials and methods to enhance efficacy and future development prospects.


Asunto(s)
Dolor Crónico , Bulbo Olfatorio , Humanos , Dolor Crónico/terapia , Animales , Bulbo Olfatorio/citología , Neuroglía , Trasplante de Células/métodos
18.
Phys Chem Chem Phys ; 26(14): 10520-10529, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38512292

RESUMEN

In this paper we investigate the relationship between the conductivity effective mass and exfoliation energy of materials to assess whether automatic sampling of the electron band structure can predict the presence of and ease of separating chemically bonded layers. We assess 22 976 materials from the Materials Project database, screen for only those that are thermodynamically stable and identify the 1000 materials with the highest standard deviation for p-type and the 1000 materials with the highest standard deviation for n-type internal conductivity effective mass tensors. We calculate the exfoliation energy of these 2000 materials and report on the correlation between effective mass and exfoliation energy. A relationship is found which is used to identify a previously unconsidered two-dimensional material and could streamline the modelling of other two-dimensional materials in the future.

19.
Biochem Biophys Res Commun ; 707: 149513, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38508051

RESUMEN

Cancer is a significant global health concern, and finding effective methods to treat it has been a focus of scientific research. It has been discovered that the growth, invasion, and metastasis of tumors are closely related to the environment in which they exist, known as the tumor microenvironment (TME). The immune response interacting with the tumor occurring within the TME constitutes the tumor immune microenvironment, and the immune response can lead to anti-tumor and pro-tumor outcomes and has shown tremendous potential in immunotherapy. A channel called the P2X7 receptor (P2X7R) has been identified within the TME. It is an ion channel present in various immune cells and tumor cells, and its activation can lead to inflammation, immune responses, angiogenesis, immunogenic cell death, and promotion of tumor development. This article provides an overview of the structure, function, and pharmacological characteristics of P2X7R. We described the concept and components of tumor immune microenvironment and the influence immune components has on tumors. We also outlined the impact of P2X7R regulation and how it affects the development of tumors and summarized the effects of drugs targeting P2X7R on tumor progression, both past and current, assisting researchers in treating tumors using P2X7R as a target.


Asunto(s)
Neoplasias , Receptores Purinérgicos P2X7 , Microambiente Tumoral , Humanos , Neoplasias/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Animales
20.
Front Comput Neurosci ; 18: 1358437, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38449670

RESUMEN

With the rapid increase of economic globalization, the significant expansion of shipping volume has resulted in shipping route congestion, causing the necessity of trajectory prediction for effective service and efficient management. While trajectory prediction can achieve a relatively high level of accuracy, the performance and generalization of prediction models remain critical bottlenecks. Therefore, this article proposes a dual-attention (DA) based end-to-end (E2E) neural network (DAE2ENet) for trajectory prediction. In the E2E structure, long short-term memory (LSTM) units are included for the task of pursuing sequential trajectory data from the encoder layer to the decoder layer. In DA mechanisms, global attention is introduced between the encoder and decoder layers to facilitate interactions between input and output trajectory sequences, and multi-head self-attention is utilized to extract sequential features from the input trajectory. In experiments, we use a ro-ro ship with a fixed navigation route as a case study. Compared with baseline models and benchmark neural networks, DAE2ENet can obtain higher performance on trajectory prediction, and better validation of environmental factors on ship navigation.

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