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1.
Small ; : e2402104, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949416

RESUMEN

To meet increasing requirement for innovative energy storage and conversion technology, it is urgent to prepare effective, affordable, and long-term stable oxygen electrocatalysts to replace precious metal-based counterparts. Herein, a two-step pyrolysis strategy is developed for controlled synthesis of Fe2O3 and Mn3O4 anchored on carbon nanotubes/nanosheets (Fe2O3-Mn3O4-CNTs/NSs). The typical catalyst has a high half-wave potential (E1/2 = 0.87 V) for oxygen reduction reaction (ORR), accompanied with a smaller overpotential (η10 = 290 mV) for oxygen evolution reaction (OER), showing substantial improvement in the ORR and OER performances. As well, density functional theory calculations are performed to illustrate the catalytic mechanism, where the in situ generated Fe2O3 directly correlates to the reduced energy barrier, rather than Mn3O4. The Fe2O3-Mn3O4-CNTs/NSs-based Zn-air battery exhibits a high-power density (153 mW cm-2) and satisfyingly long durability (1650 charge/discharge cycles/550 h). This work provides a new reference for preparation of highly reversible oxygen conversion catalysts.

2.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1020586

RESUMEN

Objective:To investigate the application of Wuxing music combined with traditional Chinese medicine bath and golden paste encapsulation in patients with psoriasis vulgaris(blood-heat syndrome).Methods:In this prospective study,80 patients with psoriasis vulgaris(blood heat syndrome)admitted to our hospital from Nov 2020 to Nov 2022 were included and randomly divided into the control group and the observation group,with 40 cases in each group.The control group received routine nursing intervention,and the observation group received Wuxing music combined with traditional Chinese medicine bath and golden paste encapsulation nursing on the basis of control group,4 weeks as a course of treatment.After 2 courses of nursing,nursing effect,the scores of SCL-90 and DQOLS,the levels of serum inflammatory factors[interleukin-13(IL-13),transforming growth factor-β(TGF-β),and tumor necrosis factor-α(TNF-α)],and nursing satisfaction were compared between the two groups.Results:The area and severity of skin lesions in the two groups were lower than before nursing,and the changes in the observation group were more significant(P<0.05).The scores of SCL-90 and DQOLS in the two groups were lower than those before nursing,and the changes in the observation group were more significant(P<0.05).The levels of IL-13,TGF-β and TNF-α in the two groups were lower than those before nursing,and the levels of these indicators in the observation group were significantly lower than those in the control group(P<0.05).The satisfaction rate of the observation group was higher than that of the control group(P<0.05).Conclusions:Wuxing music combined with traditional Chinese medicine bath and golden paste encapsulation has a significant nursing effect on patients with psoriasis vulgaris(blood heat syndrome).It can decrease serum inflammatory factors,alleviate the degree of skin lesions,and iprove quality of life and nursing satisfaction.

3.
Phytochemistry ; 217: 113920, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37951561

RESUMEN

Ten lignans, including six previously undescribed phenolic ester glycosyl lignans (1-6), were isolated from a well-known traditional Chinese medicine, Qin-Jiao, which is the dry root of Gentiana macrophylla Pall. (Gentianaceae). Their structures were determined by spectroscopic and chemical methods, especially 2D NMR techniques. Quantum chemical calculations of theoretical ECD spectra allowed the determination of their absolute configurations. Refer to its traditional applications for the treatment of rheumatic arthralgia and hepatopathy, these compounds were evaluated on a TNF-α induced MH7A human synoviocyte inflammation model and a D-GalN induced AML12 hepatocyte injury model. Compounds 1, 2, 5, and 6 significantly reduced the release of proinflammatory cytokine IL-1ß in MH7A cells at 15 µM and they also could strongly protect AML12 cells against D-GalN injury at 30 µM. Flow cytometry and Western blot analysis showed that compound 5 ameliorated D-GalN induced AML12 cell apoptosis by upregulating the expression of anti-apoptotic Bcl-2 protein and down-regulating the expression of pro-apoptotic Bax protein.


Asunto(s)
Medicamentos Herbarios Chinos , Gentiana , Lignanos , Humanos , Gentiana/química , Lignanos/farmacología , Glucósidos/farmacología , Glucósidos/química , Medicamentos Herbarios Chinos/farmacología , Inflamación
4.
Plants (Basel) ; 12(24)2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38140413

RESUMEN

The one-time application of blended urea (BU), combining controlled-release urea (CRU) and uncoated urea, has proven to be a promising nitrogen (N) management strategy. However, the long-term sustainability of blending urea remains largely unexplored. To assess whether a single application of blended urea could effectively replace split uncoated urea applications, a long-term field experiment was conducted in the North China Plain (NCP). The results indicated that, when compared to common urea (CU) at the optimal N rate (180 kg N ha-1), BU achieved comparable grain yields, N uptake and NUE (61% vs. 62). BU exhibited a 12% higher 0-20 cm soil organic nitrogen stock and a 9% higher soil organic carbon (C) stock. Additionally, BU reduced life-cycle reactive N (Nr) losses and the N footprint by 10%, and lowered greenhouse gas (GHG) emissions and the C footprint by 7%. From an economic analysis perspective, BU demonstrated comparable private profitability and a 3% greater ecosystem economic benefit. Therefore, BU under the optimal N rate has the potential to substitute split applications of common urea in the long-term and can be regarded as a sustainable N management strategy for wheat and maize production in the NCP.

5.
Sci Adv ; 9(37): eadh7820, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37703377

RESUMEN

1,3-ß-Glucan serves as the primary component of the fungal cell wall and is produced by 1,3-ß-glucan synthase located in the plasma membrane. This synthase is a molecular target for antifungal drugs such as echinocandins and the triterpenoid ibrexafungerp. In this study, we present the cryo-electron microscopy structure of Saccharomyces cerevisiae 1,3-ß-glucan synthase (Fks1) at 2.47-Å resolution. The structure reveals a central catalytic region adopting a cellulose synthase fold with a cytosolic conserved GT-A-type glycosyltransferase domain and a closed transmembrane channel responsible for glucan transportation. Two extracellular disulfide bonds are found to be crucial for Fks1 enzymatic activity. Through structural comparative analysis with cellulose synthases and structure-guided mutagenesis studies, we gain previously unknown insights into the molecular mechanisms of fungal 1,3-ß-glucan synthase.


Asunto(s)
beta-Glucanos , Microscopía por Crioelectrón , Antifúngicos , Catálisis
6.
Nat Commun ; 14(1): 4776, 2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37553334

RESUMEN

Chitin is one of the most abundant natural biopolymers and serves as a critical structural component of extracellular matrices, including fungal cell walls and insect exoskeletons. As a linear polymer of ß-(1,4)-linked N-acetylglucosamine, chitin is synthesized by chitin synthases, which are recognized as targets for antifungal and anti-insect drugs. In this study, we determine seven different cryo-electron microscopy structures of a Saccharomyces cerevisiae chitin synthase in the absence and presence of glycosyl donor, acceptor, product, or peptidyl nucleoside inhibitors. Combined with functional analyses, these structures show how the donor and acceptor substrates bind in the active site, how substrate hydrolysis drives self-priming, how a chitin-conducting transmembrane channel opens, and how peptidyl nucleoside inhibitors inhibit chitin synthase. Our work provides a structural basis for understanding the function and inhibition of chitin synthase.


Asunto(s)
Quitina Sintasa , Quitina , Quitina Sintasa/química , Quitina Sintasa/metabolismo , Quitina/metabolismo , Microscopía por Crioelectrón , Nucleósidos/metabolismo , Saccharomyces cerevisiae/metabolismo , Catálisis
7.
Plants (Basel) ; 12(7)2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37050116

RESUMEN

Although nitrogen (N) fertilizer application plays an essential role in improving crop productivity, an inappropriate management can result in negative impacts on environment and human health. To break this dilemma, a 12-year field experiment (2008-2019) with five N application rates was conducted on the North China Plain (NCP) to evaluate the integrated impacts of optimizing N management (Opt. N, 160 kg N ha-1 on average) on agronomic, environmental, health, and economic performances of summer maize production. Over the 12-year study, the Opt. N treatment achieved the maximal average grain yield (10.6 Mg ha-1) and grain protein yield (793 kg ha-1) among five N treatments. The life cycle assessment methodology was applied to determine the negative impacts on environmental and human health, and both of them increased with the N rate. Compared with the farmers' conventional N rate (250 kg N ha-1), the Opt. N treatment reduced acidification, eutrophication, global warming, and energy depletion potentials by 29%, 42%, 35%, and 18%, respectively, and reduced the health impact by 32% per Mg of grain yield or grain protein yield produced. Both the Opt. N and Opt. N*50-70% treatments resulted in high private profitability (2038 USD ha-1), ecosystem economic benefit (1811 USD ha-1), and integrated compensation benefit (17,548 USD ha-1). This study demonstrates the potential benefits of long-term optimizing of N management to maintain high maize yields and grain quality, to reduce various environmental impacts and health impacts, and to enhance economic benefits. These benefits can be further enhanced when Opt. N was combined with advanced agronomic management practices. The results also suggest that reducing the optimal N rate from 160 to 145 kg N ha-1 is achievable to further reduce the negative impacts while maintaining high crop productivity. In conclusion, optimizing the N management is essential to promote sustainable summer maize production on the NCP.

8.
Science ; 379(6636): 996-1003, 2023 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-36893255

RESUMEN

Metabolic networks are interconnected and influence diverse cellular processes. The protein-metabolite interactions that mediate these networks are frequently low affinity and challenging to systematically discover. We developed mass spectrometry integrated with equilibrium dialysis for the discovery of allostery systematically (MIDAS) to identify such interactions. Analysis of 33 enzymes from human carbohydrate metabolism identified 830 protein-metabolite interactions, including known regulators, substrates, and products as well as previously unreported interactions. We functionally validated a subset of interactions, including the isoform-specific inhibition of lactate dehydrogenase by long-chain acyl-coenzyme A. Cell treatment with fatty acids caused a loss of pyruvate-lactate interconversion dependent on lactate dehydrogenase isoform expression. These protein-metabolite interactions may contribute to the dynamic, tissue-specific metabolic flexibility that enables growth and survival in an ever-changing nutrient environment.


Asunto(s)
Metabolismo de los Hidratos de Carbono , L-Lactato Deshidrogenasa , Metaboloma , Humanos , Ácidos Grasos/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Especificidad de Órganos , Espectrometría de Masas/métodos , Regulación Alostérica
10.
Journal of Experimental Hematology ; (6): 1333-1339, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1009990

RESUMEN

OBJECTIVE@#To explore the efficacy of venetoclax (VEN) plus azacitidine (AZA) in patients with FLT3-ITD mutated relapsed/refractory acute myeloid leukemia (FLT3-ITDmut R/R AML) and analyze the molecular genetic characteristics of the patients.@*METHODS@#Clinical baseline characteristics and follow-up data of 16 R/R AML patients treatd with VEN plus AZA in the hematology department of Shenzhen Second People's Hospital from November 2018 to April 2021 were collected. Leukemia related genes were detected by next-generation sequencing(NGS) or PCR. The relationship between the efficacy of VEN plus AZA and molecular genetics characteristics of patients with FLT3-ITDmut R/R AML were analyzed.@*RESULTS@#14.3% (1/7) of the patients in FLT3-ITDmut group and 22.2% (2/9) of the patients in FLT3-ITDwt group achieved complete remission (CR)/CR with incomplete blood count recovery (CRi), respectively, with no significant difference (P=0.69). There was no significant difference in overall response rate (ORR) (CR/CRi+PR) between FLT3-ITDmut group and FLT3-ITDwt group [42.9%(3/7) vs 44.4%(4/9), P=0.95], too. The median overall survival (OS) time of FLT3-ITDmut patients was significantly shorter than that of FLT3-ITDwt patients (130 vs 300 days, respectively) (P =0.02). Co-existing mutations of FLT3-ITD and IDH1 were detected in one patient who achieved CR. Co-existing mutations of FLT3-ITD and SF3B1 were found in one patient who achieved PR. Three FLT3-ITDmut R/R AML patients accompanied with NPM1 mutation had no response to VEN plus AZA.@*CONCLUSION@#VEN plus AZA showed a certain effect on patients with FLT3-ITDmut R/R AML. To improve OS of the patients, bridging transplantation is need. IDH1 and SF3B1 mutations might predict that patients with FLT3-ITDmut R/R AML have treatment response to VEN plus AZA, while the combination of NPM1 mutation may indicate poor response.


Asunto(s)
Humanos , Nucleofosmina , Pronóstico , Leucemia Mieloide Aguda/genética , Mutación , Azacitidina/uso terapéutico , Tirosina Quinasa 3 Similar a fms/genética
11.
Chinese Journal of Hematology ; (12): 373-379, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-984632

RESUMEN

Objective: To explore the molecular features of chronic myelomonocytic leukemia (CMML) . Methods: According to 2022 World Health Organization (WHO 2022) classification, 113 CMML patients and 840 myelodysplastic syndrome (MDS) patients from March 2016 to October 2021 were reclassified, and the clinical and molecular features of CMML patients were analyzed. Results: Among 113 CMML patients, 23 (20.4%) were re-diagnosed as acute myeloid leukemia (AML), including 18 AML with NPM1 mutation, 3 AML with KMT2A rearrangement, and 2 AML with MECOM rearrangement. The remaining 90 patients met the WHO 2022 CMML criteria. In addition, 19 of 840 (2.3%) MDS patients met the WHO 2022 CMML criteria. At least one gene mutation was detected in 99% of CMML patients, and the median number of mutations was 4. The genes with mutation frequency ≥ 10% were: ASXL1 (48%), NRAS (34%), RUNX1 (33%), TET2 (28%), U2AF1 (23%), SRSF2 (21.1%), SETBP1 (20%), KRAS (17%), CBL (15.6%) and DNMT3A (11%). Paired analysis showed that SRSF2 was frequently co-mutated with ASXL1 (OR=4.129, 95% CI 1.481-11.510, Q=0.007) and TET2 (OR=5.276, 95% CI 1.979-14.065, Q=0.001). SRSF2 and TET2 frequently occurred in elderly (≥60 years) patients with myeloproliferative CMML (MP-CMML). U2AF1 mutations were often mutually exclusive with TET2 (OR=0.174, 95% CI 0.038-0.791, Q=0.024), and were common in younger (<60 years) patients with myelodysplastic CMML (MD-CMML). Compared with patients with absolute monocyte count (AMoC) ≥1×10(9)/L and <1×10(9)/L, the former had a higher median age of onset (60 years old vs 47 years old, P<0.001), white blood cell count (15.9×10(9)/L vs 4.4×10(9)/L, P<0.001), proportion of monocytes (21.5% vs 15%, P=0.001), and hemoglobin level (86 g/L vs 74 g/L, P=0.014). TET2 mutations (P=0.021) and SRSF2 mutations (P=0.011) were more common in patients with AMoC≥1×10(9)/L, whereas U2AF1 mutations (P<0.001) were more common in patients with AMoC<1×10(9)/L. There was no significant difference in the frequency of other gene mutations between the two groups. Conclusion: According to WHO 2022 classification, nearly 20% of CMML patients had AMoC<1×10(9)/L at the time of diagnosis, and MD-CMML and MP-CMML had different molecular features.


Asunto(s)
Humanos , Anciano , Persona de Mediana Edad , Leucemia Mielomonocítica Crónica/genética , Pronóstico , Factor de Empalme U2AF/genética , Mutación , Síndromes Mielodisplásicos/genética , Leucemia Mieloide Aguda/genética
12.
Chinese Journal of Neurology ; (12): 552-556, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-994867

RESUMEN

Endometrial carcinoma is one of common malignant tumors in female reproductive system, but it is extremely rare in leptomeningeal metastasis. The clinical manifestations and signs of meningeal carcinomatosis are complex and not specific. It is difficult to get a precise diagnosis early, and it has high rate of misdiagnosis and missed diagnosis. Accurate diagnosis and treatment of a case of leptomeningeal metastasis from endometrial carcinoma by next-generation sequencing and cerebrospinal fluid cytology are reported. The patient is an elderly female with a history of endometrial cancer. The main manifestations were fever, headache and dizziness; cerebrospinal fluid cytology showed tumor cells; AKT1 gene and TP53 gene were detected in endometrial carcinoma tissue, plasma and cerebrospinal fluid by next-generation sequencing. After treatment with intrathecal chemotherapy, immunotherapy combined with anti angiogenesis, the patient′s condition still progressed gradually and died finally. The purpose of this case report is to raise clinical awareness of recognition and treatment in early meningeal metastasis of endometrial carcinoma.

13.
Chinese Acupuncture & Moxibustion ; (12): 1056-1061, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1007442

RESUMEN

OBJECTIVE@#To observe the effects of Xingnao Kaiqiao (regaining consciousness and opening orifices) acupuncture therapy on the expression of hypoxia-inducible factor 1α (HIF-1α) and Nod-like receptor protein 3 (NLRP3) in cerebral ischemia-reperfusion rats, and to explore the mechanism of acupuncture against cerebral ischemia-reperfusion injury.@*METHODS@#Seventy-two male SD rats were randomly divided into a sham-operation group, a model group, an acupuncture group and a non-point acupuncture group, with 18 rats in each one. Using modified Longa thread embolization method, the rat model of acute focal cerebral ischemia was prepared; and after 2 h ischemia, the reperfusion was performed to prepared the model of cerebral ischemia-reperfusion. Immediately after reperfusion, Xingnao Kaiqiao acupuncture method was applied to bilateral "Neiguan" (PC 6) and "Shuigou" (GV 26) in the acupuncture group, while in the non-point acupuncture group, acupuncture was delivered at non-points and all of the needles were retained for 30 min in these two groups. The samples were collected 24 h after reperfusion in the rats of each group. Zea-Longa neurological deficit score was used to evaluate the degree of cerebral neurological impairment, TTC staining was adopted to observe the volume percentage of cerebral infarction, HE staining was provided to observe the morphological changes of brain, and Western blot was applied for detecting the expression of HIF-1α and NLRP3 proteins in the cerebral cortex on the right side.@*RESULTS@#Compared with the sham-operation group, neurological deficit score and volume percentage of cerebral infarction were increased in the model group (P<0.01), and HIF-1α and NLRP3 protein expression was elevated (P<0.01). Compared with the model group, neurological deficit score and volume percentage of cerebral infarction were decreased (P<0.01), and HIF-1α and NLRP3 protein expression was lower (P<0.01) in the acupuncture group. There was no significant difference in above indexes in the non-point acupuncture group compared with the model group (P>0.05). Compared with the sham-operation group, the brain tissue of the rats in the model group and the non-point acupuncture group was loose and edema, and the nuclei were shriveled. The brain tissue morphology in the acupuncture group was similar to that of the sham-operation group.@*CONCLUSION@#Acupuncture can alleviate cerebral ischemia-reperfusion injury, and its mechanism may be related to the regulation of HIF-1α/NLRP3 signaling pathway to attenuate inflammatory response.


Asunto(s)
Masculino , Animales , Ratas , Ratas Sprague-Dawley , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Terapia por Acupuntura , Daño por Reperfusión/terapia , Isquemia Encefálica/terapia , Infarto Cerebral/terapia , Proteínas NLR
14.
Zhongguo Gu Shang ; 35(12): 1115-20, 2022 Dec 25.
Artículo en Chino | MEDLINE | ID: mdl-36572424

RESUMEN

OBJECTIVE: To investigate clinical outcomes of countertraction method in treating irreducible subcoracoid dislocation of shoulder joint combined with Hill-Sacks injury. METHODS: A total of 56 patients with irreducible subcoracoid dislocation of the shoulder joint combined with Hill-Sacks injury admitted from December 2013 to June 2020 were retrospectively analyzed. Under the anesthesia of shoulder joint cavity injection, the reduction was performed by using anti-traction method (experimental group) and traditional Hippocrates method (control group), 28 cases in each group. There were 11 males and 17 females in experimental group, with an average age of (61.95±19.32) years old, 9 cases on the left side, and 19 cases on the right side. Twelve males and 16 females in control group, with an average age of (63.13±12.75) years old, 11 cases on the left side, 17 cases on the right side. The curative effects between two groups were evaluated before and after operation, including the success rate of reduction, the duration of reduction, the distance from successful reduction to injury, complications and functional rehabilitation(Constant score of shoulder joint). RESULTS: The success rates of reduction in experimental group and control group were 92.86%(26/28) and 67.86% (19/28), respectively, and the difference was statistically significant (P<0.05). The duration of simple reduction was (4.25±2.13) min and ( 6.31±1.69) min, the difference was statistically significant (P<0.05);the time from successful reduction to injury was (9.16±0.94) h and (8.94±1.31) h, respectively, with no significant difference(P>0.05). There were no complications such as vascular nerve injury and fracture in experimental group, 2 cases of axillary nerve injury and 1 case of humeral head fracture in control group. Constant scores of shoulder joint between experimental group and control group were (92.34±5.62) points and (90.91±4.73) points, respectively, with no significant difference (P>0.05). CONCLUSION: For patients with irreducible subcoracoid dislocation of the shoulder joint with Hill-Sacks injury, the countertraction method under anesthesia of the shoulder joint cavity achieved a higher success rate and few complications.


Asunto(s)
Luxaciones Articulares , Inestabilidad de la Articulación , Luxación del Hombro , Lesiones del Hombro , Articulación del Hombro , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Articulación del Hombro/cirugía , Luxación del Hombro/cirugía , Luxación del Hombro/complicaciones , Estudios Retrospectivos , Luxaciones Articulares/complicaciones , Inestabilidad de la Articulación/cirugía
15.
Sci Rep ; 12(1): 16059, 2022 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-36163391

RESUMEN

The primary function of heat shock transcription factor (HSF) in the heat shock response is to activate the transcription of genes encoding heat shock proteins (HSPs). The phloem-feeding insect Bemisia tabaci (Gennadius) is an important pest of cotton, vegetables and ornamentals that transmits several plant viruses and causes enormous agricultural losses. In this study, the gene encoding HSF (Bthsf1) was characterized in MED B. tabaci. The full-length cDNA encoded a protein of 652 amino acids with an isoelectric point of 5.55. The BtHSF1 deduced amino acid sequence showed strong similarity to HSF in other insects. Expression analyses using quantitative real-time PCR indicated that Bthsf1 was significantly up-regulated in B. tabaci adults and pupae during thermal stress. Although Bthsf1 was induced by both hot and cold stress, the amplitude of expression was greater in the former. Bthsf1 had distinct, significant differences in expression pattern during different duration of high but not low temperature stress. Oral ingestion of dsBthsf1 repressed the expression of Bthsf1 and four heat shock proteins (Bthsp90, Bthsp70-3, Bthsp20 and Bthsp19.5) in MED B. tabaci during hot and cold stress. In conclusion, our results show that Bthsf1 is differentially expressed during high and low temperature stress and regulates the transcription of multiple hsps in MED B. tabaci.


Asunto(s)
Hemípteros , Aminoácidos/metabolismo , Animales , ADN Complementario/metabolismo , Factores de Transcripción del Choque Térmico/genética , Factores de Transcripción del Choque Térmico/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Hemípteros/fisiología , Temperatura , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
16.
Int J Biol Macromol ; 219: 500-507, 2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-35932807

RESUMEN

The PA28 family proteasome activators play important roles in regulating proteasome activities. Though the three paralogs (PA28α, PA28ß, and PA28γ) are similar in terms of primary sequence, they show significant differences in expression pattern, cellular localization and most importantly, biological functions. While PA28αß is responsible for promoting peptidase activity of proteasome to facilitate MHC-I antigen processing, but unable to promote protein degradation, PA28γ is well-known to not only promote peptidase activity but also proteolytic activity of proteasome. However, why this paralog has the unique function remains elusive. Previous structural studies have mainly focused on mammalian PA28α, PA28ß and PA28αß heptamers, while structural studies on mammalian PA28γ of atomic resolution are still absent to date. In the present work, we determined the Cryo-EM structure of the human PA28γ heptamer at atomic resolution, revealing interesting unique structural features that may hint our understanding the functional mechanisms of this proteasome activator.


Asunto(s)
Autoantígenos , Complejo de la Endopetidasa Proteasomal , Animales , Microscopía por Crioelectrón , Humanos , Mamíferos/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis
17.
Bioorg Chem ; 127: 105970, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35749854

RESUMEN

Six pairs of enantiomeric phthalide dimers (1-6) were isolated from the rhizomes of Ligusticum chuanxiong. Their structures and absolute configurations were elucidated by NMR spectroscopy, X-ray diffraction analyses, and electronic circular dichroism calculations. Compounds (+)-1 and (-)-1 are new phthalide dimers, featuring two classes of monomeric units (a phthalide and an unusual 2,3-seco-phthalide) with an uncommon linkage (3,6'/8,3'a). Compounds (+)-2 and (-)-3 are also novel phthalide dimers that had not been reported previously. Although (-)-2 and (+)-3 have been successfully isolated in previous studies, their absolute configurations were not unambiguously determined. As for compound 4, it was reported as a racemate in one study, and one of its enantiomers was identified in a subsequent study. Herein, all enantiomeric phthalide dimers were successfully separated, and their absolute configurations were determined. The inhibitory effects of all isolates against lipopolysaccharide-induced nitric oxide production were tested using RAW264.7 cells. The results show that compounds (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, (-)-4, (+)-5, (+)-6, and (-)-6 have inhibitory activities, with compound (+)-5 being the most active (IC50 value of 4.3 ± 1.3 µM).


Asunto(s)
Benzofuranos , Ligusticum , Antiinflamatorios/farmacología , Benzofuranos/química , Benzofuranos/farmacología , Ligusticum/química , Estructura Molecular , Rizoma/química
18.
Molecules ; 27(11)2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35684456

RESUMEN

Lung cancer continues to be the world's leading cause of cancer death and the treatment of non-small cell lung cancer (NSCLC) has attracted much attention. The tubers of Bletilla striata are regarded as "an excellent medicine for lung diseases" and as the first choice to treat several lung diseases. In this study, seventeen phenanthrene derivatives, including two new compounds (1 and 2), were isolated from the tubers of B. striata. Most compounds showed cytotoxicity against A549 cells. An EdU proliferation assay, a cell cycle assay, a wound healing assay, a transwell migration assay, a flow cytometry assay, and a western blot assay were performed to further investigate the effect of compound 1 on A549 cells. The results showed that compound 1 inhibited cell proliferation and migration and promoted cell apoptosis in A549 cells. The mechanisms might correlate with the regulation of the Akt, MEK/ERK, and Bcl-2/Bax signaling pathways. These results suggested that the phenanthrenes of B. striata might be important and effective substances in the treatment of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Orchidaceae , Fenantrenos , Células A549 , Apoptosis , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Proliferación Celular , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Fenantrenos/farmacología
19.
J Exp Med ; 219(6)2022 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-35532553

RESUMEN

Hypoxia contributes to airway inflammation and remodeling in several lung diseases; however, exactly how hypoxic pulmonary epithelium regulates allergic inflammation remains to be fully characterized. Here, we report that conditional deletion of the E3 ubiquitin ligase VHL in lung epithelial cells resulted in exacerbated type 2 responses accompanied by selective increase of group 2 innate lymphoid cells (ILC2s) at steady state and following inflammation or helminth infection. Ablation of expression of the hypoxia-inducible factor 2α (HIF2α) significantly reversed VHL-mediated ILC2 activation. VHL deficiency in lung epithelial cells caused increased expression of the peptide hormone adrenomedullin (ADM), and our data suggest that HIF2α controls Adm expression. ADM directly promoted ILC2 activation both in vitro and in vivo. Our findings indicate that the hypoxic response mediated by the VHL-HIF2α axis is critical for control of pulmonary type 2 responses by increasing ADM expression in lung epithelia, causing ILC2 activation.


Asunto(s)
Inmunidad Innata , Enfermedades Pulmonares , Adrenomedulina , Epitelio , Humanos , Hipoxia , Inflamación , Pulmón , Linfocitos
20.
ACS Med Chem Lett ; 13(2): 196-202, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35178175

RESUMEN

A series of brigatinib derivatives were designed and synthesized as new potent and selective EGFRT790M/C797S inhibitors. One of the most potent and selective compounds 18k strongly suppressed the EGFRL858R/T790M/C797S and EGFR19Del/T790M/C797S kinases with IC50 values of 0.7 and 3.6 nM, respectively, which were over 54-fold more potent than the lead compound. 18k also demonstrated promising EGFRT790M/C797S mutant selectivity, and was 94-fold less potent against the wild type EGFR. A cocrystal structure of EGFRT790M/C797S with a close derivative 18f was solved to provide insight on the inhibitor's binding mode. Moreover, compound 18k was orally bioavailable and demonstrated highly desirable PK properties, making it a promising lead compound for further structural optimization.

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