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1.
Int J Biol Macromol ; 263(Pt 1): 130309, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382779

RESUMO

Maintaining protein balance within a cell is essential for proper cellular function, and disruptions in the ubiquitin-proteasome pathway, which is responsible for degrading and recycling unnecessary or damaged proteins, can lead to various diseases. Deubiquitinating enzymes play a vital role in regulating protein homeostasis by removing ubiquitin chains from substrate proteins, thereby controlling important cellular processes, such as apoptosis and DNA repair. Among these enzymes, ubiquitin-specific protease 7 (USP7) is of particular interest. USP7 is a cysteine protease consisting of a TRAF region, catalytic region, and C-terminal ubiquitin-like (UBL) region, and it interacts with tumor suppressors, transcription factors, and other key proteins involved in cell cycle regulation and epigenetic control. Moreover, USP7 has been implicated in the pathogenesis and progression of various diseases, including cancer, inflammation, neurodegenerative conditions, and viral infections. Overall, characterizing the functions of USP7 is crucial for understanding the pathophysiology of diverse diseases and devising innovative therapeutic strategies. This article reviews the structure and function of USP7 and its complexes, its association with diseases, and its known inhibitors and thus represents a valuable resource for advancing USP7 inhibitor development and promoting potential future treatment options for a wide range of diseases.


Assuntos
Proteostase , Ubiquitina , Peptidase 7 Específica de Ubiquitina/genética , Peptidase 7 Específica de Ubiquitina/química , Peptidase 7 Específica de Ubiquitina/metabolismo , Ubiquitina/química , Domínio Catalítico , Ubiquitina Tiolesterase/química
2.
Int J Biol Macromol ; 254(Pt 3): 126801, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37689288

RESUMO

Histone lysine-specific demethylase 1 (LSD1) expression has been evaluated in multiple tumors, including gastric cancer (GC). However, the mechanisms underlying LSD1 dysregulation in GC remain largely unclear. In this study, neural precursor cell-expressed developmentally down-regulated protein 8 (NEDD8) was identified to be conjugated to LSD1 at K63 by ubiquitin-conjugating enzyme E2 M (UBE2M), and this neddylated LSD1 could promote LSD1 ubiquitination and degradation, leading to a decrease of GC cell stemness and chemoresistance. Herein, our findings revealed a novel mechanism of LSD1 neddylation and its contribution to decreasing GC cell stemness and chemoresistance. Taken together, our findings may whistle about the future application of neddylation inhibitors.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Ubiquitinação , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Histona Desmetilases
3.
Front Pharmacol ; 14: 1225515, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745048

RESUMO

Object: This research intended to probe the antibacterial effect and pharmacodynamic substances of Tea-Seed Oil (TSO) through the use of ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) analysis, network analysis, and molecular docking. Methods: The major chemical components in the methanol-extracted fractions of TSO were subjected to UPLC-Q-TOF-MS. Network pharmacology and molecular docking techniques were integrated to investigate the core components, targets, and potential mechanisms of action through which the TSO exert their antibacterial properties. To evaluate the inhibitory effects, the minimum inhibitory concentration and diameter of the bacteriostatic circle were calculated for the potential active ingredients and their equal ratios of combinatorial components (ERCC) against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. Moreover, the quantification of the active constituents within TSO was achieved through the utilization of high-performance liquid chromatography (HPLC). Results: The methanol-extracted fractions contained a total of 47 chemical components, predominantly consisting of unsaturated fatty acids and phenolic compounds. The network pharmacology analysis and molecular docking analysis revealed that various components, including gallocatechin, gallic acid, epigallocatechin, theophylline, chlorogenic acid, puerarin, and phlorizin, have the ability to interact with critical core targets such as serine/threonine protein kinase 1 (AKT1), epidermal growth factor receptor (EGFR), a monoclonal antibody to mitogen-activated protein kinase 14 (MAPK14), HSP90AA1, and estrogen receptor 1 (ESR1). Furthermore, these components can modulate the phosphatidylinositol-3-kinase protein kinase B (PI3K-AKT), estrogen, MAPK and interleukin 17 (IL-17) signaling pathways, hereby exerting antibacterial effects. In vitro validation trials have found that seven components, namely gallocatechin, gallic acid, epigallocatechin, theophylline, chlorogenic acid, puerarin, and phloretin, displayed substantial inhibitory effects on E. coli, S. aureus, P. aeruginosa, and C. albicans, and are typically present in tea oil, with a total content ranging from 15.87∼24.91 µg·g-1. Conclusion: The outcomes of this investigation possess the possibility to expand our knowledge base concerning the utilization of TSO, furnish a theoretical framework for the exploration of antibacterial drugs and cosmetics derived from inherently occurring TSO, and establish a robust groundwork for the advancement and implementations of TOS products within clinical settings.

4.
World J Clin Cases ; 11(26): 6268-6273, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37731559

RESUMO

BACKGROUND: Bronchial Dieulafoy's disease (BDD) is characterized by the erosion of an anomalous artery in the submucosa of the bronchus. The etiology of pediatric BDD is mainly congenital dysplasia of bronchus and pulmonary arteries, which is different from chronic inflammatory injury of the airway in adult patients. The internal thoracic artery, subclavian artery, and intercostal artery are known to be involved in the blood supply to the BDD lesion in children. CASE SUMMARY: We report a case of BDD in a 4-year-old boy with recurrent hemoptysis for one year. Selective angiography showed a dilated right bronchial artery, and anastomosis of its branches with the right lower pulmonary vascular network. Bronchoscopy showed nodular protrusion of the bronchial mucosa with a local scar. Selective embolization of the bronchial artery was performed to stop bleeding. One month after the first intervention, the symptoms of hemoptysis recurred. A computed tomography angiogram (CTA) showed another tortuous and dilated feeding artery in the right lower lung, which was an abnormal ascending branch of the inferior phrenic artery (IPA). The results of angiography were consistent with the CTA findings. The IPA was found to be another main supplying artery, which was not considered during the first intervention. Finally, the IPA was also treated by microsphere embolization combined with coil interventional closure. During the one-year follow-up, the patient never experienced hemoptysis. CONCLUSION: The supplying arteries of the bleeding lesion in children with BDD may originate from multiple different aortopulmonary collateral arteries, and the IPA should be considered to reduce missed diagnosis. CTA is a noninvasive radiological examination for the screening of suspected vessels, which shows a high coincidence with angiography, and can serve as the first choice for the diagnosis of BDD.

5.
Inorg Chem ; 62(37): 15164-15172, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37672772

RESUMO

We investigate Ge3n+1O-/0 (n = 1-3) clusters using anion photoelectron spectroscopy and theoretical calculations. The results show that the lowest energy structure of Ge4O- is a bent Cs symmetric trigonal bipyramidal structure, while Ge4O has a C3v symmetric trigonal bipyramidal structure. Ge7O- has two coexisting low-lying isomers, the first one can be viewed as a Ge2O unit interacting with a Ge5 trigonal bipyramid, the second one can be regarded as an O atom interacting with a Ge7 pentagonal bipyramid; whereas Ge7O has a C3v symmetric structure with a Ge atom and an O atom capping a Ge6 trigonal antiprism from the bottom and top, respectively. The structures of Ge10O- and Ge10O can be obtained by adding an O atom to different binding sites of a C3v symmetric Ge10. Chemical bonding analyses of Ge3n+1O (n = 1-3) reveal that the O atom interacts with its neighboring three Ge atoms forming one 4c-2e σ bond and two 4c-2e π bonds in the top Ge3O trigonal pyramid, while the terminal Ge atom forms one 4c-2e σ bond in the bottom Ge4 trigonal pyramid. The large HOMO-LUMO gaps of Ge3n+1O (n = 1-3) indicate that they have good stabilities. Ab initio molecular dynamics simulations suggest that both Ge7O and Ge10O are dynamically stable in general at 300 and 500 K. The current work suggests that the C3v symmetric Ge3 units and the insertion growth pattern may be viable for constructing 1D germanium oxide nanostructures with the chemical formula of Ge3n+1O.

6.
Oncogenesis ; 12(1): 45, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37717015

RESUMO

Neddylation is the writing of monomers or polymers of neural precursor cells expressed developmentally down-regulated 8 (NEDD8) to substrate. For neddylation to occur, three enzymes are required: activators (E1), conjugators (E2), and ligators (E3). However, the central role is played by the ubiquitin-conjugating enzymes E2M (UBE2M) and E2F (UBE2F), which are part of the E2 enzyme family. Recent understanding of the structure and mechanism of these two proteins provides insight into their physiological effects on apoptosis, cell cycle arrest and genome stability. To treat cancer, it is therefore appealing to develop novel inhibitors against UBE2M or UBE2F interactions with either E1 or E3. In this evaluation, we summarized the existing understanding of E2 interaction with E1 and E3 and reviewed the prospective of using neddylation E2 as a pharmacological target for evolving new anti-cancer remedies.

7.
Nano Lett ; 23(17): 8378-8384, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37651712

RESUMO

The discovery of graphene and its excellent properties inspired the search for more two-dimensional (2D) materials. Understanding the structures and properties of the smallest repeating units as well as crystal 2D materials is helpful for designing 2D materials. As germanium tends to form three-dimensional structures, the preparation of germanium-based 2D nanomaterials is still a challenge. Herein, we report a Ge3O3 cluster with the potential to construct a germanium oxide 2D nanostructure. We conduct a combined anion photoelectron spectroscopy and theoretical study on Ge3O3-/0. The structure of Ge3O3- is a Cs symmetric nonplanar six-membered ring, while that of Ge3O3 is a D3h symmetric planar six-membered ring. Chemical bonding analyses reveal that Ge3O3 exhibits π aromaticity. First-principle results suggest that a buckled honeycomb 2D nanostructure with a wide band gap of 3.14 eV may be produced based on Ge3O3, which is promising in optoelectronic applications especially in blue, violet, and ultraviolet regions.

8.
J Biomed Sci ; 30(1): 60, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37525190

RESUMO

Dysregulation of various cells in the tumor microenvironment (TME) causes immunosuppressive functions and aggressive tumor growth. In combination with immune checkpoint blockade (ICB), epigenetic modification-targeted drugs are emerging as attractive cancer treatments. Lysine-specific demethylase 1 (LSD1) is a protein that modifies histone and non-histone proteins and is known to influence a wide variety of physiological processes. The dysfunction of LSD1 contributes to poor prognosis, poor patient survival, drug resistance, immunosuppression, etc., making it a potential epigenetic target for cancer therapy. This review examines how LSD1 modulates different cell behavior in TME and emphasizes the potential use of LSD1 inhibitors in combination with ICB therapy for future cancer research studies.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Histonas/metabolismo , Neoplasias/tratamento farmacológico , Epigênese Genética , Histona Desmetilases/genética
9.
BMC Med ; 21(1): 256, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37452335

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) have reported single-nucleotide polymorphisms (SNPs) in the VRK serine/threonine kinase 2 gene (VRK2) showing genome-wide significant associations with major depression, but the regulation effect of the risk SNPs on VRK2 as well as their roles in the illness are yet to be elucidated. METHODS: Based on the summary statistics of major depression GWAS, we conducted population genetic analyses, epigenome bioinformatics analyses, dual luciferase reporter assays, and expression quantitative trait loci (eQTL) analyses to identify the functional SNPs regulating VRK2; we also carried out behavioral assessments, dendritic spine morphological analyses, and phosphorylated 4D-label-free quantitative proteomics analyses in mice with Vrk2 repression. RESULTS: We identified a SNP rs2678907 located in the 5' upstream of VRK2 gene exhibiting large spatial overlap with enhancer regulatory marks in human neural cells and brain tissues. Using luciferase reporter gene assays and eQTL analyses, the depression risk allele of rs2678907 decreased enhancer activities and predicted lower VRK2 mRNA expression, which is consistent with the observations of reduced VRK2 level in the patients with major depression compared with controls. Notably, Vrk2-/- mice exhibited depressive-like behaviors compared to Vrk2+/+ mice and specifically repressing Vrk2 in the ventral hippocampus using adeno-associated virus (AAV) lead to consistent and even stronger depressive-like behaviors in mice. Compared with Vrk2+/+ mice, the density of mushroom and thin spines in the ventral hippocampus was significantly altered in Vrk2-/- mice, which is in line with the phosphoproteomic analyses showing dysregulated synapse-associated proteins and pathways in Vrk2-/- mice. CONCLUSIONS: Vrk2 deficiency mice showed behavioral abnormalities that mimic human depressive phenotypes, which may serve as a useful murine model for studying the pathophysiology of depression.


Assuntos
Estudo de Associação Genômica Ampla , Leucemia Mieloide Aguda , Humanos , Camundongos , Animais , Depressão/genética , Polimorfismo de Nucleotídeo Único , Proteínas Serina-Treonina Quinases/metabolismo
10.
Am J Transl Res ; 15(3): 2098-2102, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37056866

RESUMO

Moyamoya disease is mainly caused by stenosis or occlusion of the terminal internal carotid artery, anterior cerebral artery, and proximal middle cerebral artery, and an abnormal vascular network is formed near the stenosis or occlusion of vascular lesions. Moyamoya disease can lead to a series of complications such as transient cerebral ischemia, cerebral infarction, and cerebral hemorrhage, which have been reported in the literature. Eye involvement with moyamoya disease is relatively rare in the literature. This article introduces a case of central retinal vein occlusion in a teenager related to moyamoya disease. The patient was only 16 years old and suddenly suffered from vision loss in the left eye. After detailed ophthalmological examination, she was diagnosed with central retinal vein occlusion in the left eye. In order to find the exact cause, we conducted head and neck CTA and brain DSA examinations on the patient, and finally found that the main cause of central retinal vein occlusion in this patient was moyamoya disease, which indicated that central retinal vein occlusion in young people may be caused by moyamoya disease in the early stage. This discovery has great clinical significance, for characteristic manifestations of the eye, suggesting that examination of moyamoya disease is a routine item for such patients, so as to achieve early detection, early diagnosis and early treatment, in order to avoid cerebral infarction, cerebral palsy, and serious or even life-threatening complications such as bleeding.

11.
J Med Chem ; 66(6): 3896-3916, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36856685

RESUMO

Histone lysine specific demethylase 1 (LSD1) has been recognized as an important epigenetic target for cancer treatment. Although several LSD1 inhibitors have entered clinical trials, the discovery of novel potent LSD1 inhibitors remains a challenge. In this study, the antipsychotic drug chlorpromazine was characterized as an LSD1 inhibitor (IC50 = 5.135 µM), and a series of chlorpromazine derivatives were synthesized. Among them, compound 3s (IC50 = 0.247 µM) was the most potent one. More importantly, compound 3s inhibited LSD1 in the cellular level and downregulated the expression of programmed cell death-ligand 1 (PD-L1) in BGC-823 and MFC cells to enhance T-cell killing response. An in vivo study confirmed that compound 3s can inhibit MFC cell proliferation without significant toxicity in immunocompetent mice. Taken together, our findings indicated that the novel LSD1 inhibitor 3s tethering a phenothiazine scaffold may serve as a lead compound for further development to activate T-cell immunity in gastric cancer.


Assuntos
Inibidores Enzimáticos , Neoplasias Gástricas , Animais , Camundongos , Inibidores Enzimáticos/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Linhagem Celular Tumoral , Clorpromazina/uso terapêutico , Linfócitos T/metabolismo , Proliferação de Células , Histona Desmetilases/metabolismo , Morte Celular , Relação Estrutura-Atividade
12.
J Phys Chem Lett ; 14(11): 2854-2861, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36917175

RESUMO

Unlike C≡O, which is common in coordination chemistry and organometallic chemistry, little is known about Si≡O or Ge≡O compounds. Here we report a Ge6O- cluster featuring a Ge≡O triple bond. The structural and chemical bonding properties of Ge6O-/0 are investigated using anion photoelectron spectroscopy and theoretical calculations. Two nearly degenerate isomers have been found for Ge6O-. The lowest-energy structure (6A) can be viewed as an O atom bonding with a tetragonal bipyramidal Ge6. The second one (6B) can be considered as an O atom interacting with a capped trigonal bipyramidal Ge6. Chemical bonding analyses reveal that Ge6O- (6A) can be viewed as a Ge≡O unit interacting with a σ antiaromatic C2v symmetric tetragonal pyramidal Ge53- moiety. Comparisons of the chemical bonding in Ge6O- (6A) with that in Ge5CO- and Ge5MnO- indicate the similar behavior of Ge≡O to C≡O and Mn≡O in its bonding to the Ge53- and Ge54- moieties.

13.
Int J Biol Macromol ; 230: 123219, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36642357

RESUMO

Histone deacetylase 6 (HDAC6) is the only member of the HDAC family that resides primarily in the cytoplasm with two catalytic domains and a ubiquitin-binding domain. HDAC6 is highly expressed in various solid tumors and participates in a wide range of biological activities, including hormone receptors, the p53 signaling pathway, and the kinase cascade signaling pathway due to its unique structural foundation and abundant substrate types. Additionally, HDAC6 can function as an oncogenic factor in solid tumors, boosting tumor cell proliferation, invasion and metastasis, drug resistance, stemness, and lowering tumor cell immunogenicity, so assisting in carcinogenesis. Pan-HDAC inhibitors for cancer prevention are associated with potential cardiotoxicity in clinical investigations. It's interesting that HDAC6 silencing didn't cause any significant harm to normal cells. Currently, the use of HDAC6 specific inhibitors, individually or in combination, is among the most promising therapies in solid tumors. This review's objective is to give a general overview of the structure, biological functions, and mechanism of HDAC6 in solid tumor cells and in the immunological milieu and discuss the preclinical and clinical trials of selective HDAC6 inhibitors. These endeavors highlight that targeting HDAC6 could effectively kill tumor cells and enhance patients' immunity during solid tumor therapy.


Assuntos
Neoplasias , Humanos , Proliferação de Células , Desacetilase 6 de Histona/metabolismo , Desacetilase 6 de Histona/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/metabolismo , Neoplasias/tratamento farmacológico
14.
Inorg Chem ; 62(5): 2033-2039, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36693231

RESUMO

We present joint anion photoelectron spectroscopy and theoretical studies for Mn2Ge6- and Mn2Ge7-. Experimental results show that Mn2Ge6- and Mn2Ge7- have vertical electron detachment energies of 2.58 ± 0.08 and 2.88 ± 0.08 eV, respectively. Both Mn2Ge6- and Mn2Ge6 have Cs symmetric structures with a Mn atom attached to a pentagonal bipyramid MnGe6. Both Mn2Ge7- and Mn2Ge7 have C2v symmetric structures, which can be considered as two Mn2Ge4 tetragonal bipyramids sharing a MnGeMn face. According to chemical bonding analyses, Mn2Ge6 could be considered as a (MnII)(MnGe62-) complex. Theoretical calculations predict that the extension of Mn2Ge7 to Mn2nGe4n+3 may be able to produce a new type of Mn-doped germanium nanostructure.

15.
Am J Phys Med Rehabil ; 102(5): 409-418, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36170751

RESUMO

OBJECTIVE: The aim of the study is to determine the effects of motor imagery training associated with conventional rehabilitation therapies on lower limb motor function recovery in poststroke patients. DESIGN: Comprehensive literature searches were performed to identify studies published before June 5, 2022. RevMan 5.3 software was used for meta-analysis. The quality of the included studies was assessed using the Cochrane risk-of-bias tool and the modified Jadad scale. The certainty of the evidence was evaluated with the Grading of Recommendations, Assessment, Development and Evaluations system. RESULT: Twenty-three trials and/or 1109 participants with motor imagery training ability were included in this review. Motor imagery training combined with conventional rehabilitation therapies versus conventional rehabilitation therapies demonstrated significant benefits in motor function, balance function, temporospatial gait variables (walking speed, stride length, and cadence) and activities of daily living. Subgroup analysis demonstrated that motor imagery training-conventional rehabilitation therapies had a better effect on improvement in motor function and activities of daily living in the acute phase and had a greater benefit on walking speed in the chronic phase. In addition, motor imagery training-conventional rehabilitation therapies resulted in greater improvements in stride length, cadence, walking ability, and balance function in the subacute phase. CONCLUSIONS: Motor imagery training-conventional rehabilitation therapies have better effects on the recovery of lower limb motor function in poststroke patients than conventional rehabilitation therapies, which may be most beneficial for lower extremity motor function recovery in the first 7 days to 6 mos.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/métodos , Atividades Cotidianas , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Extremidade Inferior
16.
Inorg Chem ; 61(50): 20524-20530, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36475633

RESUMO

The structures and chemical bonding of Ge6MnO- are investigated using anion photoelectron spectroscopy and theoretical calculations. The lowest energy structure of Ge6MnO- is found to have a C5v symmetric structure with an O atom attached to a pentagonal bipyramidal MnGe6. Chemical bonding analyses reveal that Ge6MnO- can be considered as a [MnV≡O]3+[Ge64-] complex with two unpaired 3d electrons on Mn. The Ge64- ligand is highly stable in Ge6MnO- and exhibits double aromaticity with 10 delocalized σ electrons and 6 delocalized π electrons. Our calculations show that the Ge64- ligand could also form [CrIV≡O]2+[Ge64-] in Na2Ge6CrO and [FeIV≡O]2+[Ge64-] in Na2Ge6FeO. The results suggest the possibility of designing and synthesizing a series of stable high-valent metal oxide anionic species with the composition [M≡O]n+[Ge64-] in the gas phase or in the salt-stabilized bulk solid materials.

17.
Inorg Chem ; 61(32): 12570-12576, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35913829

RESUMO

The structures, chemical bonding, and magnetic properties of MnGe3O-/0 and MnGe4O-/0 are investigated by photoelectron spectroscopy and ab initio calculations. The experimental vertical electron detachment energies of MnGe3O- and MnGe4O- are measured to be 2.06 ± 0.04 and 2.64 ± 0.04 eV, respectively. The structures of MnGe3O-/0 and MnGe4O-/0 can be viewed as evolved from quadrilateral MnGe3 or tetrahedral MnGe3. It is found that both MnGe3O- and MnGe3O have Cs symmetric planar structures with an O atom attached to quadrilateral MnGe3. The structure of MnGe4O- is nonplanar with an O atom and an additional Ge atom attached to tetrahedral MnGe3, while that of MnGe4O is planar with an O atom and an additional Ge atom attached to quadrilateral MnGe3. Chemical bonding analyses reveal the existence of Ge═O double bonds in MnGe3O and MnGe4O. Magnetic property analyses suggest that MnGe3O and MnGe4O are ferromagnetic with total spin magnetic moments of 5 µB.

18.
Cell Mol Life Sci ; 79(8): 413, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35819633

RESUMO

Cancer immunotherapy is a rapidly developing and effective method for the treatment of a variety of malignancies in recent years. As a significant immune checkpoint, programmed cell death 1 ligand 1 (PD-L1) and its receptor programmed cell death protein 1 (PD-1) play the most significant role in cancer immune escape and cancer immunotherapy. Though PD-L1 have become an important target for drug development and there have been various approved drugs and clinic trials targeting it, and various clinical response rate and adverse reactions prevent many patients from benefiting from it. In recent years, combination trials have become the main direction of PD-1/PD-L1 antibodies development. Here, we summarized PD-L1 biofunctions and key roles in various cancers along with the development of PD-L1 inhibitors. The regulators that are involved in controlling PD-L1 expression including post-translational modification, mRNA level regulation as well as degradation and exosome secretory pathway of PD-L1 were focused. This systematic summary may provide comprehensive understanding of different regulations on PD-L1 as well as a broad prospect for the search of the important regulator of PD-L1. The regulatory factors of PD-L1 can be potential targets for immunotherapy and increase strategies of immunotherapy in combination.


Assuntos
Antígeno B7-H1 , Neoplasias , Antígeno B7-H1/metabolismo , Humanos , Imunoterapia/métodos , Neoplasias/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Processamento de Proteína Pós-Traducional
19.
Phys Chem Chem Phys ; 24(31): 18627-18634, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35894793

RESUMO

We investigate the structures and properties of Mn2Ge4-/0 and Mn2Ge5-/0 by anion photoelectron spectroscopy and theoretical calculations. The vertical detachment energies (VDEs) of Mn2Ge4- and Mn2Ge5- are measured to be 2.69 eV and 2.49 eV, respectively. It is found that neutral Mn2Ge4 has an approximate quadrilateral bipyramidal structure with C2v symmetry and 11B2 electronic state. Neutral Mn2Ge5 has a pentagonal bipyramidal structure with C2v symmetry and 11B2 electronic state. The 4s-based molecular orbitals of the Mn atoms participate in the chemical bonding with the Ge4 and Ge5 fragments in Mn2Ge4 and Mn2Ge5. In Mn2Ge4, the two Mn atoms interact with the Ge4 moiety via four GeGeMn 3c-2e σ bonds. In Mn2Ge5, the two Mn atoms interact with the Ge5 moiety via one MnGeMn 3c-2e σ bond and four GeMnGe 3c-2e σ bonds. The analysis of magnetic properties reveals that both Mn2Ge4 and Mn2Ge5 exhibit highly ferromagnetic characteristics with a magnetic moment of 10 µB which mainly originated from the Mn atoms. These double Mn atom doped germanium clusters may provide new opportunities to design novel spintronic devices featuring high magnetic moments.

20.
Antimicrob Agents Chemother ; 66(7): e0007322, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35758720

RESUMO

Metronidazole (Met) is the first choice for treating Helicobacter pylori (Hp). However, Hp is easy to resistant, making Met unable to be widely used. How to overcome Hp's Met resistance is still an issue. In this study, Met was used as the primary raw material with linolenic acid to prepare a novel compound-linolenic acid-metronidazole (Lla-Met). The MIC, minimum bactericidal concentration (MBC), colonization amount of Hp in gastric mucosa, etc., were evaluated, respectively. Lla-Met was successfully prepared by the detection of nuclear magnetic resonance, etc., and its MIC and MBC to Hp were 2~4 µg/mL, 8~16 µg/mL. Moreover, in vivo experiments, Lla-Met significantly reduced the colonization of drug-resistant Hp in gastric mucosa. In the toxicity test, Lla-Met inhibited rate to GES-1 and BGC823 cells were 15% at 128 µg/mL; the mice were administered 10 times treatment Lla-Met treatment (240 mg/kg), have no difference significant injuries were found in their stomach, liver, spleen, kidney, and weight. In addition, Hp G27 continued for 18 days in vitro with sub-Lla-Met concentration, G27 did not show drug resistance to Lla-Met; Lla-Met did not exert an effect on non-Hp species with 128 µg/mL; Compared with a neutral environment, when the acid concentration is 3.0, Lla-Met is not decomposed and has better stability. Conclusion: Lla-Met, a newly prepared compound, has relatively well antibacterial of Met-resistant and sensitive Hp, with a capability of overcoming the metronidazole resistance of Hp.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Claritromicina/farmacologia , Resistência a Medicamentos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Metronidazol/farmacologia , Metronidazol/uso terapêutico , Camundongos , Ácido alfa-Linolênico/farmacologia
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