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1.
Trends Biochem Sci ; 48(6): 568-584, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36959016

RESUMO

4-Hydroxyphenylpyruvate dioxygenase (HPPD) plays a key role in tyrosine metabolism and has been identified as a promising target for herbicide and drug discovery. The structures of HPPD complexed with different types of inhibitors have been determined previously. We summarize the structures of HPPD complexed with structurally diverse molecules, including inhibitors, natural products, substrates, and catalytic intermediates; from these structures, the detailed inhibitory mechanisms of different inhibitors were analyzed and compared, and the key structural factors determining the slow-binding behavior of inhibitors were identified. Further, we propose four subpockets that accommodate different inhibitor substructures. We believe that these analyses will facilitate in-depth understanding of the enzymatic reaction mechanism and enable the design of new inhibitors with higher potency and selectivity.


Assuntos
4-Hidroxifenilpiruvato Dioxigenase , Herbicidas , 4-Hidroxifenilpiruvato Dioxigenase/química , 4-Hidroxifenilpiruvato Dioxigenase/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Herbicidas/farmacologia , Herbicidas/química , Catálise , Biologia
2.
Annu Rev Med ; 75: 189-204, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-37669567

RESUMO

Complement constitutes a major part of the innate immune system. The study of complement in human health has historically focused on infection risks associated with complement protein deficiencies; however, recent interest in the field has focused on overactivation of complement as a cause of immune injury and the development of anticomplement therapies to treat human diseases. The kidneys are particularly sensitive to complement injury, and anticomplement therapies for several kidney diseases have been investigated. Overactivation of complement can result from loss-of-function mutations in complement regulators; gain-of-function mutations in key complement proteins such as C3 and factor B; or autoantibody production, infection, or tissue stresses, such as ischemia and reperfusion, that perturb the balance of complement activation and regulation. Here, we provide a high-level review of the status of anticomplement therapies, with an emphasis on the transition from rare diseases to more common kidney diseases.


Assuntos
Nefropatias , Doenças Raras , Humanos , Doenças Raras/tratamento farmacológico , Doenças Raras/genética , Proteínas Inativadoras do Complemento , Nefropatias/tratamento farmacológico , Nefropatias/genética , Mutação
3.
Nature ; 579(7798): 219-223, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32132712

RESUMO

Ultrathin two-dimensional (2D) semiconducting layered materials offer great potential for extending Moore's law of the number of transistors in an integrated circuit1. One key challenge with 2D semiconductors is to avoid the formation of charge scattering and trap sites from adjacent dielectrics. An insulating van der Waals layer of hexagonal boron nitride (hBN) provides an excellent interface dielectric, efficiently reducing charge scattering2,3. Recent studies have shown the growth of single-crystal hBN films on molten gold surfaces4 or bulk copper foils5. However, the use of molten gold is not favoured by industry, owing to its high cost, cross-contamination and potential issues of process control and scalability. Copper foils might be suitable for roll-to-roll processes, but are unlikely to be compatible with advanced microelectronic fabrication on wafers. Thus, a reliable way of growing single-crystal hBN films directly on wafers would contribute to the broad adoption of 2D layered materials in industry. Previous attempts to grow hBN monolayers on Cu (111) metals have failed to achieve mono-orientation, resulting in unwanted grain boundaries when the layers merge into films6,7. Growing single-crystal hBN on such high-symmetry surface planes as Cu (111)5,8 is widely believed to be impossible, even in theory. Nonetheless, here we report the successful epitaxial growth of single-crystal hBN monolayers on a Cu (111) thin film across a two-inch c-plane sapphire wafer. This surprising result is corroborated by our first-principles calculations, suggesting that the epitaxial growth is enhanced by lateral docking of hBN to Cu (111) steps, ensuring the mono-orientation of hBN monolayers. The obtained single-crystal hBN, incorporated as an interface layer between molybdenum disulfide and hafnium dioxide in a bottom-gate configuration, enhanced the electrical performance of transistors. This reliable approach to producing wafer-scale single-crystal hBN paves the way to future 2D electronics.

4.
J Immunol ; 210(10): 1543-1551, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36988282

RESUMO

Complement factor D (FD) is a rate-limiting enzyme of the alternative pathway (AP). Recent studies have suggested that it is synthesized as an inactive precursor and that its conversion to enzymatically active FD is catalyzed by mannan-binding lectin-associated serine protease 3 (MASP3). However, whether MASP3 is essential for AP complement activity remains uncertain. It has been shown that Masp1/3 gene knockout did not prevent AP complement overactivation in a factor H-knockout mouse, and a human patient lacking MASP3 still retained AP complement activity. In this study, we have assessed AP complement activity in a Masp3-knockout mouse generated by CRISPR/Cas9 editing of the Masp1/3 gene. We confirmed specific Masp3 gene inactivation by showing intact MASP1 protein expression and absence of mature FD in the mutant mice. Using several assays, including LPS- and zymosan-induced C3b deposition and rabbit RBC lysis tests, we detected plasma concentration-dependent AP complement activity in Masp3 gene-inactivated mice. Thus, although not measurable in 5% plasma, significant AP complement activity was detected in 20-50% plasma of Masp3 gene-inactivated mice. Furthermore, whereas FD gene deletion provided more than 90% protection of CD55/Crry-deficient RBCs from AP complement-mediated extravascular hemolysis, Masp3 gene deletion only provided 30% protection in the same study. We also found pro-FD to possess intrinsic catalytic activity, albeit at a much lower level than mature FD. Our data suggest that MASP3 deficiency reduces but does not abrogate AP complement activity and that this is explained by intrinsic pro-FD activity, which can be physiologically relevant in vivo.


Assuntos
Lectina de Ligação a Manose , Serina Proteases Associadas a Proteína de Ligação a Manose , Animais , Humanos , Camundongos , Coelhos , Fator D do Complemento/metabolismo , Via Alternativa do Complemento/fisiologia , Lectina de Ligação a Manose da Via do Complemento , Proteínas do Sistema Complemento , Camundongos Knockout , Serina Proteases Associadas a Proteína de Ligação a Manose/genética
5.
Am J Physiol Cell Physiol ; 326(2): C647-C658, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38189133

RESUMO

Thoracic aortic aneurysm/dissection (TAAD) is a lethal vascular disease, and several pathological factors participate in aortic medial degeneration. We previously discovered that the complement C3a-C3aR axis in smooth muscle cells promotes the development of thoracic aortic dissection (TAD) through regulation of matrix metalloproteinase 2. However, discerning the specific complement pathway that is activated and elucidating how inflammation of the aortic wall is initiated remain unknown. We ascertained that the plasma levels of C3a and C5a were significantly elevated in patients with TAD and that the levels of C3a, C4a, and C5a were higher in acute TAD than in chronic TAD. We also confirmed the activation of the complement in a TAD mouse model. Subsequently, knocking out Cfb (Cfb) or C4 in mice with TAD revealed that the alternative pathway and Cfb played a significant role in the TAD process. Activation of the alternative pathway led to generation of the anaphylatoxins C3a and C5a, and knocking out their receptors reduced the recruitment of inflammatory cells to the aortic wall. Moreover, we used serum from wild-type mice or recombinant mice Cfb as an exogenous source of Cfb to treat Cfb KO mice and observed that it exacerbated the onset and rupture of TAD. Finally, we knocked out Cfb in the FBN1C1041G/+ Marfan-syndrome mice and showed that the occurrence of TAA was reduced. In summary, the alternative complement pathway promoted the development of TAAD by recruiting infiltrating inflammatory cells. Targeting the alternative pathway may thus constitute a strategy for preventing the development of TAAD.NEW & NOTEWORTHY The alternative complement pathway promoted the development of TAAD by recruiting infiltrating inflammatory cells. Targeting the alternative pathway may thus constitute a strategy for preventing the development of TAAD.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Azidas , Desoxiglucose/análogos & derivados , Humanos , Camundongos , Animais , Via Alternativa do Complemento , Metaloproteinase 2 da Matriz , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/metabolismo , Aneurisma da Aorta Torácica/patologia , Dissecção Aórtica/genética , Inflamação
6.
J Am Chem Soc ; 146(20): 14203-14212, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38733560

RESUMO

Nanomedicines often rely on noncovalent self-assembly and encapsulation for drug loading and delivery. However, challenges such as reproducibility issues due to the multicomponent nature, off-target activation caused by premature drug release, and complex pharmacokinetics arising from assembly dissociation have hindered their clinical translation. In this study, we introduce an innovative design concept termed single molecular nanomedicine (SMNM) based on macrocyclic carrier-drug conjugates. Through the covalent linkage of two chemotherapy drugs to a hypoxia-cleavable macrocyclic carrier, azocalix[4]arene, we obtained two self-included complexes to serve as SMNMs. The intramolecular inclusion feature of the SMNMs has not only demonstrated comprehensive shielding and protection for the drugs but also effectively prevented off-target drug leakage, thereby significantly reducing their side effects and enhancing their antitumor therapeutic efficacy. Additionally, the attributes of being a single component and molecularly dispersed confer advantages such as ease of preparation and good reproducibility for SMNMs, which is desirable for clinical applications.


Assuntos
Antineoplásicos , Calixarenos , Portadores de Fármacos , Nanomedicina , Humanos , Portadores de Fármacos/química , Nanomedicina/métodos , Calixarenos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Animais , Compostos Macrocíclicos/química , Camundongos , Linhagem Celular Tumoral , Liberação Controlada de Fármacos
7.
J Transl Med ; 22(1): 46, 2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212795

RESUMO

BACKGROUND: Ovarian cancer (OC) is a malignant neoplasm that displays increased vascularization. Angiopoietin-like 4 (ANGPTL4) is a secreted glycoprotein that functions as a regulator of cell metabolism and angiogenesis and plays a critical role in tumorigenesis. However, the precise role of ANGPTL4 in the OC microenvironment, particularly its involvement in angiogenesis, has not been fully elucidated. METHODS: The expression of ANGPTL4 was confirmed by bioinformatics and IHC in OC. The potential molecular mechanism of ANGPTL4 was measured by RNA-sequence. We used a series of molecular biological experiments to measure the ANGPTL4-JAK2-STAT3 and ANGPTL4-ESM1 axis in OC progression, including MTT, EdU, wound healing, transwell, xenograft model, oil red O staining, chick chorioallantoic membrane assay and zebrafish model. Moreover, the molecular mechanisms were confirmed by Western blot, Co-IP and molecular docking. RESULTS: Our study demonstrates a significant upregulation of ANGPTL4 in OC specimens and its strong association with unfavorable prognosis. RNA-seq analysis affirms that ANGPTL4 facilitates OC development by driving JAK2-STAT3 signaling pathway activation. The interaction between ANGPTL4 and ESM1 promotes ANGPTL4 binding to lipoprotein lipase (LPL), thereby resulting in reprogrammed lipid metabolism and the promotion of OC cell proliferation, migration, and invasion. In the OC microenvironment, ESM1 may interfere with the binding of ANGPTL4 to integrin and vascular-endothelial cadherin (VE-Cad), which leads to stabilization of vascular integrity and ultimately promotes angiogenesis. CONCLUSION: Our findings underscore that ANGPTL4 promotes OC development via JAK signaling and induces angiogenesis in the tumor microenvironment through its interaction with ESM1.


Assuntos
Cistadenocarcinoma Seroso , Janus Quinase 2 , Neoplasias Ovarianas , Fator de Transcrição STAT3 , Animais , Feminino , Humanos , Microambiente Tumoral , Simulação de Acoplamento Molecular , Angiogênese , Peixe-Zebra/metabolismo , Carcinogênese , Proliferação de Células , Carcinoma Epitelial do Ovário , Neoplasias Ovarianas/genética , Linhagem Celular Tumoral , Proteína 4 Semelhante a Angiopoietina/genética , Proteínas de Neoplasias , Proteoglicanas
8.
Chemistry ; : e202402891, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39196966

RESUMO

The visible light-induced decarboxylative cascade reaction of fluoroalkyl carboxylic acids has been achieved for the efficient synthesis of fluorinated compounds. However, most of the transformations rely on noble iridium metal complex. Herein, a visible light-induced metal-free decarboxylative cascade reaction of fluoroalkyl carboxylic acids has been realized. This protocol features simple operation, transition metal, and good functional group tolerance.

9.
BMC Cancer ; 24(1): 576, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730348

RESUMO

OBJECTIVE: Nasopharyngeal adenoid cystic carcinoma (NACC) is a rare malignancy with special biological features. Controversies exist regarding the treatment approach and prognostic factors in the IMRT era. This study aimed to evaluate the long-term outcomes and management approaches in NACC. METHODS: Fifty patients with NACC at our institution between 2010 and 2020 were reviewed. Sixteen patients received primary radiotherapy (RT), and 34 patients underwent primary surgery. RESULTS: Between January 2010 and October 2020, a total of 50 patients with pathologically proven NACC were included in our analysis. The median follow-up time was 58.5 months (range: 6.0-151.0 months). The 5-year overall survival rate (OS) and progression-free survival rate (PFS) were 83.9% and 67.5%, respectively. The 5-year OS rates of patients whose primary treatment was surgery and RT were 90.0% and 67.3%, respectively (log-rank P = 0.028). The 5-year PFS rates of patients whose primary treatment was surgery or RT were 80.8% and 40.7%, respectively (log-rank P = 0.024). Multivariate analyses showed that nerve invasion and the pattern of primary treatment were independent factors associated with PFS. CONCLUSIONS: Due to the relative insensitivity to radiation, primary surgery seemed to provide a better chance of disease control and improved survival in NACC. Meanwhile, postoperative radiotherapy should be performed for advanced stage or residual tumours. Cranial nerve invasion and treatment pattern might be important factors affecting the prognosis of patients with NACC.


Assuntos
Carcinoma Adenoide Cístico , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Humanos , Carcinoma Adenoide Cístico/radioterapia , Carcinoma Adenoide Cístico/mortalidade , Carcinoma Adenoide Cístico/patologia , Carcinoma Adenoide Cístico/cirurgia , Masculino , Feminino , Radioterapia de Intensidade Modulada/métodos , Pessoa de Meia-Idade , Adulto , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Idoso , Estudos Retrospectivos , Carcinoma Nasofaríngeo/radioterapia , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Adulto Jovem , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento , Seguimentos , Adolescente , Intervalo Livre de Progressão
10.
Chemphyschem ; 25(5): e202300960, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38179835

RESUMO

Prussian blue analogues (PBAs) have advantages such as high voltage and low cost, making them one kind of the promising positive electrode materials for sodium-ion batteries. Particle dispersion is a key physical parameter of electrode materials, and understanding its impact on electrochemical performance is a prerequisite for obtaining high-performance PBAs. In this article, two PBAs samples with different particle dispersion were synthesized through sodium citrate-assisted co-precipitation method by means of staying and stirring. The influence of particle dispersion on electrochemical performance was investigated through polarization curve and AC impedance tests. It was found that PBAs with well-dispersed particles exhibited excellent rate performance, with a capacity of ~120 mAh g-1 at 1 C rate and a capacity retention of 75 % after 100 cycles. The capacity retention rate could reach 63 % at 5 C rate, far higher than that of PBAs samples with poor particle dispersion. From the perspective of electrochemical kinetics analysis, it has been shown that PBAs with well-dispersed particles exhibit smaller electrochemical polarization and faster Na+ diffusion reaction kinetics, which are key factors in achieving excellent rate performance.

11.
Protein Expr Purif ; 222: 106531, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38852715

RESUMO

The SARS-CoV-2 main protease (Mpro) plays a crucial role in virus amplification and is an ideal target for antiviral drugs. Currently, authentic Mpro is prepared through two rounds of proteolytic cleavage. In this method, Mpro carries a self-cleavage site at the N-terminus and a protease cleavage site followed by an affinity tag at the C-terminus. This article proposes a novel method for producing authentic Mpro through single digestion. Mpro was constructed by fusing a His tag containing TEV protease cleavage sites at the N-terminus. The expressed recombinant protein was digested by TEV protease, and the generated protein had a decreased molecular weight and significantly increased activity, which was consistent with that of authentic Mpro generated by the previous method. These findings indicated that authentic Mpro was successfully obtained. Moreover, the substrate specificity of Mpro was investigated. Mpro had a strong preference for Phe at position the P2, which suggested that the S2 subsite was an outstanding target for designing inhibitors. This article also provides a reference for the preparation of Mpro for sudden coronavirus infection in the future.


Assuntos
Proteases 3C de Coronavírus , SARS-CoV-2 , SARS-CoV-2/enzimologia , SARS-CoV-2/genética , Proteases 3C de Coronavírus/genética , Proteases 3C de Coronavírus/química , Proteases 3C de Coronavírus/metabolismo , Especificidade por Substrato , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , COVID-19/virologia
12.
Nutr Cancer ; 76(5): 432-441, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439655

RESUMO

BACKGROUND: Observational studies suggests that diets and medications affect bladder cancer (BC) development, which are subject to confounding and difficult to make causal inference. Here we aimed to investigate whether those observational associations are causal and determining the potential directions and pathways. METHODS: We used 2-sample Mendelian randomization (MR) analysis to assess associations of dietary intakes, medication uses and molecules with BC risk. Genetic summary data were derived from participants of predominantly European ancestry with rigorous instruments selection, where univariable MR, mediation MR and multivariable MR were performed. RESULTS: The results of univariable MR showed 4 dietary intakes and 4 medication uses having a protective effect on BC, while 4 circulating metabolites, 440 circulating proteins and 2 gut microbes were observed to be causally associated with BC risk. Through mediation MR, we found 572 analytes showing consistent mediating effects between dietary intakes or medication uses and BC risk. Furthermore, 9 out of 16 diet-medication pairs showed significant interactions and alterations on BC when consumed jointly. CONCLUSION: In summary, the findings obtained from the current study have important implications for informing prevention strategies that point to potential lifestyle interventions or medication prescriptions to reduce the risk of developing BC.HighlightsThe current study extends observational literature in showing the importance of diets and medications on bladder cancer prevention.The associations of diets and medications on bladder cancer prevention might be through circulating metabolites, circulating proteins and gut microbiotaOur results provide a new understanding of interactions in certain diet-medication pairs which should be taken into account by both physicians and patients during the development of a treatment strategy.


Assuntos
Ascomicetos , Neoplasias da Bexiga Urinária , Humanos , Análise da Randomização Mendeliana , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/prevenção & controle , Estilo de Vida , Ingestão de Alimentos
13.
J Org Chem ; 89(15): 10614-10623, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39051432

RESUMO

A photocatalyst-free and EDA complex-enabled radical cascade cyclization reaction of inactive alkenes with bromodifluoroacetamides was reported for the divergent synthesis of fluorine-containing tetralones and quinazolinones. In this transformation, persulfates as electron donors and difluoro bromamide as electron acceptors generate the EDA complex. This is a promising photochemical method with advantages such as mild reaction conditions, simple operation, being metal-free, and excellent functional group tolerance.

14.
Inorg Chem ; 63(36): 16713-16725, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39178213

RESUMO

Ammonium dinitramide (ADN), as a novel and environmentally friendly oxidizer, has strong hygroscopicity when exposed to high-humidity air, which seriously hinders its application in solid propellants. Modification of oxidizers by cocrystallization is an effective strategy to improve the hygroscopicity of energetic components. In this paper, the theoretical simulation of ADN/CL-20 cocrystals was developed via a directional hydrogen bonding design to establish a cocrystal with improved hygroscopicity. Intermolecular interaction analyses reveal that hydrogen bonds and van der Waals interactions synergistically lead to the formation of cocrystals. The ADN/CL-20 cocrystal was prepared experimentally by the spray drying self-assembly technique, and the corresponding thermal analysis and sensitivity properties were conducted to illustrate the thermal stability and high safety. Furthermore, the critical relative humidity (CRH) measurement was carried out to evaluate the hygroscopicity of the cocrystal, exhibiting a certain degree of antihygroscopic effect with a CRH of 65%. The hydrogen bonds formed between ADN and CL-20 saturate the ammonium ions of ADN, further preventing ADN from absorbing water molecules in the air. The ADN/CL-20 cocrystal has high specific impulse characteristics (Isp: 272.6 s). Accordingly, this work clearly demonstrates that the ADN/CL-20 cocrystal is expected to be used in a solid propellant to make up for the deficiency of the ADN oxidizer.

15.
Phys Chem Chem Phys ; 26(3): 2629-2637, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38174360

RESUMO

Using first-principles calculations, we predicted three novel superhard semiconducting structures of C8B2N2 with a space group of P3m1. We investigated their mechanical properties and electronic structures up to 100 GPa. These three structures were successfully derived by substituting carbon (C) atoms with isoelectronic boron (B) and nitrogen (N) atoms in the P3m1 phase, which is the most stable structure of BCN and exhibits exceptional mechanical properties. Our results indicated that these structures had superior energy over previously reported t-C8B2N2, achieved by replacing C atoms in the diamond supercell with B and N atoms. To ensure their stable existence, we thoroughly examined their mechanical and dynamical stabilities, and we found that their hardness values reached 82.4, 83.1, and 82.0 GPa, which were considerably higher than that of t-C8B2N2 and even surpassing the hardness of c-BN. Calculations of the electron localization function revealed that the stronger carbon-carbon covalent bonds made them much harder than t-C8B2N2. Additionally, our further calculations of band structures revealed that these materials had indirect bandgaps of 4.164, 4.692, and 3.582 eV. These findings suggest that these materials have the potential to be used as superhard semiconductors, potentially surpassing conventional superhard materials.

16.
Phys Chem Chem Phys ; 26(15): 11611-11617, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38546106

RESUMO

Many BF2 complexes of heteroaromatics are well known for their dual-state emission (DSE) properties. However, AIE and ACQ effects have also been observed in certain cases. To date, no rational explanations have been proposed for these uncommon photoluminescence (PL) behaviours. The current research prepared four BF2 complexes of N-benzoyl 2-aminobenzothiazoles with diversified photoluminescence (PL) properties as model compounds and utilized quantum chemical calculation tools to address this issue. Theoretical calculations revealed that the electron-donating groups (EDGs) at the para-position of the exocyclic phenyl ring exert significant influence on their ground-state electronic structures and vertical excitation features. Potential energy curve (PEC) analysis showed that the exocyclic phenyl ring and NMe2 could not function as effective rotors due to elevated energy barriers. Only the NPh2 of BFBB-3 could spontaneously rotate ∼60° to induce the formation of an emissive twisted intramolecular charge transfer (TICT) state. The two-channel model involving both vibronic relaxation and S0/S1 surface crossing revealed that the drastic narrowing of the S1/S0 energy gap in the region approaching minimun energy conical intersection (MECI) led to the generation of a dark state in BFBB-1. The small energy barrier to access the dark-state region makes the resulting fast internal conversion a competitive channel for excited-state deactivation. In contrast, the presence of EDGs in BFBB-2 and 4 inhibits this pathway, thereby resulting in intense fluorescence emissions in solution. In addition, crystallographic analysis illustrated that the F atoms perpendicular to the polyheterocycle promoted a slipped face-to-face packing mode and enhanced intermolecular interactions. The efficiencies of their solid-state emissions are mainly affected by the degree of π-π overlaps.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38901628

RESUMO

OBJECTIVE: To conduct a systematic review and meta-analysis to understand the difference in objectively measured physical activities (PAs) between children with and without developmental coordination disorder (DCD). DATA SOURCES: A systematic literature search of 4 databases (PubMed, Science Direct, Web of Science, and Cochrane library) was conducted in July 2023. STUDY SELECTION: Studies that met the following criteria were considered classified children with DCD based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), DSM-IV-Text Revision, or DSM-V diagnosis criteria, evaluated PA using objective measurements and provided the amount of time spent in PA and/or sedentary behavior, included a control group of typically developing children, and written in English. DATA EXTRACTION: Data extracted from all included studies were: first author's surname and publication year, study design, country, total sample size, the measure of PA, the intensity of PA, categories of PA level, and main finding(s). DATA SYNTHESIS: Twelve articles met the inclusion criteria for the systematic review, 10 of which were included in the meta-analysis. The overall mean difference in moderate-to-vigorous PA (MVPA) between 2 groups was -0.17 (95% CI, -0.25 to -0.09), (I2=48.7%, P=.029). A subgroup analysis by age (ie, school-aged vs. preschool) showed a significant pooled effect size with no heterogeneity in school-aged children (ie, 6-14y) (standardized mean difference=-0.27, 95% CI, -0.38 to -0.16, I2=43.1%, P=.08). CONCLUSIONS: Children with DCD spent significantly less time participating in MVPA, particularly those aged between 6 and 14 years. These findings highlight the need for increased awareness among parents and physicians regarding insufficient participation in PA among children with DCD.

18.
Mar Drugs ; 22(9)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39330290

RESUMO

The actinomycete genus Rhodococcus is known for its diverse biosynthetic enzymes, with potential in pollutant degradation, chemical biocatalysis, and natural product exploration. Comparative genomics have analyzed the distribution patterns of non-ribosomal peptide synthetases (NRPSs) in Rhodococcus. The diversity and specificity of its secondary metabolism offer valuable insights for exploring natural products, yet remain understudied. In the present study, we analyzed the distribution patterns of biosynthetic gene clusters (BGCs) in the most comprehensive Rhodococcus genome data to date. The results show that 86.5% of the gene cluster families (GCFs) are only distributed in a specific phylogenomic-clade of Rhodococcus, with the most predominant types of gene clusters being NRPS and ribosomally synthesized and post-translationally modified peptides (RiPPs). In-depth mining of RiPP gene clusters revealed that Rhodococcus encodes many clade-specific novel RiPPs, with thirteen core peptides showing antibacterial potential. High-throughput elicitor screening (HiTES) and non-targeted metabolomics revealed that a marine-derived Rhodococcus strain produces a large number of new aurachin-like compounds when exposed to specific elicitors. The present study highlights the diversity and specificity of secondary biosynthetic potential in Rhodococcus, and provides valuable information for the targeted exploration of novel natural products from Rhodococcus, especially for phylogenomic-clade-specific metabolites.


Assuntos
Produtos Biológicos , Família Multigênica , Filogenia , Rhodococcus , Metabolismo Secundário , Rhodococcus/genética , Rhodococcus/metabolismo , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Genoma Bacteriano , Antibacterianos/farmacologia , Antibacterianos/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
19.
Ecotoxicol Environ Saf ; 273: 116173, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38452703

RESUMO

Per- and polyfluoroalkyl (PFAS) substances are enduring industrial materials. 17ß-Hydroxysteroid dehydrogenase isoform 1 (17ß-HSD1) is an estrogen metabolizing enzyme, which transforms estrone into estradiol in human placenta and rat ovary. Whether PFAS inhibit 17ß-HSD1 and what the structure-activity relationship (SAR) remains unexplored. We screened 18 PFAS for inhibiting human and rat 17ß-HSD1 in microsomes and studied their SAR and mode of action(MOA). Of the 11 perfluorocarboxylic acids (PFCAs), C8-C14 PFCAs at a concentration of 100 µM substantially inhibited human 17ß-HSD1, with order of C11 (half-maximal inhibition concentration, IC50, 8.94 µM) > C10 (10.52 µM) > C12 (14.90 µM) > C13 (30.97 µM) > C9 (43.20 µM) > C14 (44.83 µM) > C8 (73.38 µM) > others. Of the 7 per- and poly-fluorosulfonic acids (PFSAs), the potency was C8S (IC50, 14.93 µM) > C7S (80.70 µM) > C6S (177.80 µM) > others. Of the PFCAs, C8-C14 PFCAs at 100 µM markedly reduced rat 17ß-HSD1 activity, with order of C11 (IC50, 9.11 µM) > C12 (14.30 µM) > C10 (18.24 µM) > C13 (25.61 µM) > C9 (67.96 µM) > C8 (204.39 µM) > others. Of the PFSAs, the potency was C8S (IC50, 37.19 µM) > C7S (49.38 µM) > others. In contrast to PFOS (C6S), the partially fluorinated compound 6:2 FTS with an equivalent number of carbon atoms demonstrated no inhibition of human and rat 17ß-HSD1 activity at a concentration of 100 µM. The inhibition of human and rat enzymes by PFAS followed a V-shaped trend from C4 to C14, with a nadir at C11. Moreover, human 17ß-HSD1 was more sensitive than rat enzyme. PFAS inhibited human and rat 17ß-HSD1 in a mixed mode. Docking analysis revealed that they bind to the NADPH and steroid binding site of both 17ß-HSD1 enzymes. The 3D quantitative SAR (3D-QSAR) showed that hydrophobic region, hydrogen bond acceptor and donor are key factors in binding to 17ß-HSD1 active sites. In conclusion, PFAS exhibit inhibitory effects on human and rat 17ß-HSD1 depending on factors such as carbon chain length, degree of fluorination, and the presence of carboxylic acid or sulfonic acid groups, with a notable V-shaped shift observed at C11.


Assuntos
Fluorocarbonos , Relação Quantitativa Estrutura-Atividade , Gravidez , Feminino , Humanos , Animais , Ratos , Simulação de Acoplamento Molecular , 17-Hidroxiesteroide Desidrogenases/química , 17-Hidroxiesteroide Desidrogenases/metabolismo , Estrona , Carbono , Fluorocarbonos/toxicidade
20.
Dysphagia ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39302429

RESUMO

Educational technologies have proven to be an effective way to guide and educate patients, allowing them to increase awareness of their dysphagia condition and how treatment will help them. In this sense, this study aimed to develop and validate the content and appearance of 3D iconographic videos, which addressed the physiological demonstration and execution of protective and facilitating swallowing maneuvers, as well as verifying the feasibility of its use in teleconsultation, having adults and elderly people with oropharyngeal dysphagia as the main target audience. The development of the 3D videos was elaborated based on a guiding scientific script, constructed from an integrative literature review. After the development of the 3D videos by the digital designer, a committee of 12 expert judges evaluated the material produced to validate the content and appearance where a minimum agreement index of 0.8 among the judges was considered satisfactory. Subsequently with the validated material, the proof of concept was conducted together with the target population of 10 dysphagic patients through individual teleconsultation via Google Meet platform. After the teleconsultation, patients responded to a Google Forms questionnaire, analyzing the videos presented. From the integrative literature review, 29 studies that contained relevant information about the physiological effects caused by swallowing maneuvers were selected. Based on this information, the scientific script was created, allowing a detailed description of the physiological events that occurred during swallowing while executing the maneuvers. With the finished script, 3D videos of swallowing maneuvers were produced. After developing the material, the committee of expert judges validated the content and appearance. The twelve items that had an agreement index below 0.8 were adjusted. Once the adjustments were completed, the videos were analyzed again, obtaining approval from the judges, and ensuring the validation of content and appearance of the material developed. A proof of concept was conducted on ten dysphagic patients. The maneuver applied was chosen according to the patient's physiological changes, causing only 4 of the 9 maneuvers to be tested, as the patients did not demonstrate changes in swallowing that would justify the use of the other maneuvers. After this, patients answered a form in which all items covered received positive evaluations, related to both ease of understanding and learning. This study allowed the development of the 3D videos with a didactic demonstration of the physiology and execution of protective and facilitating swallowing maneuvers, in addition to having its content and appearance validity assured through analysis by the committee of expert judges.

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