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1.
Nano Lett ; 23(24): 11809-11817, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38048290

RESUMO

Insect sex pheromones as an alternative to chemical pesticides hold promising prospects in pest control. However, their burst release and duration need to be optimized. Herein, pheromone-loaded core-shell fibers composed of degradable polycaprolactone and polyhydroxybutyrate were prepared by coaxial electrospinning. The results showed that this core-shell fiber had good hydrophobic performance and thermal stability, and the light transmittance in the ultraviolet band was only below 40%, which provided protection to pheromones. The core-shell structure alleviated the burst release of pheromone in the fiber and extended the release time to about 133 days. In the field, the pheromone-loaded core-shell fibers showed the same continuous and efficient trapping of Spodoptera litura as the commercial carriers. More importantly, the electrospun fibers combined with biomaterials had a degradability unmatched by commercial carriers. The structure design strategy provides ideas for the innovative design of pheromone carriers and is a potential tool for the management of agricultural pests.


Assuntos
Materiais Biocompatíveis , Feromônios
2.
Opt Lett ; 48(10): 2704-2707, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37186745

RESUMO

The dielectric laser accelerator (DLA) is a promising candidate for next-generation table-top and even on-chip particle accelerators. Long-range focusing of a tiny-size electron bunch on chip is crucial for the practical applications of DLA, which has been a challenge. Here we propose a bunch focusing scheme, which uses a pair of readily available few-cycle terahertz (THz) pulses to drive an array of millimeter-scale prisms via the inverse Cherenkov effect. The THz pulses are reflected and refracted multiple times through the prism arrays, synchronizing with and periodically focusing the electron bunch along the bunch channel. Cascade bunch-focusing is realized by making the electromagnetic field phase experienced by electrons in each stage of the array, that is, the synchronous phase, in the focusing phase region. The focusing strength can be adjusted via changing the synchronous phase and THz field intensity, optimization of which will sustain the stable bunch transportation in a tiny-size bunch channel on chip. This bunch-focusing scheme sets a base for developing a long-acceleration-range and high-gain DLA.

3.
Int J Med Sci ; 20(12): 1570-1583, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37859698

RESUMO

Background: The aim of this study was to investigate whether calcium-sensing receptor (CaSR) was involved in HRF-mediated exacerbation of MI/R injury through NLRP3 inflammasome activation and pyroptosis. Methods: In vivo, a rat MI/R model was established by ligating the left coronary artery, and short-term HRF exposure was induced during reoxygenation. Then, TUNEL, H&E, Masson staining, immunohistochemical (IHC) and serum levels of lactate dehydrogenase (LDH) and creatine kinase isoenzyme (CK), as well as the expression levels of CaSR and pyroptosis-related proteins in heart tissues, were measured. H9c2 cells were cultured to create a hypoxia/reoxygenation (H/R) model and exposed to different concentrations of RF. After pretreatment with the CaSR activator gadolinium chloride (GdCl3) and inhibitor NPS2143 in the H/R model and treatment with HRF, we compared cellular viability, TUNEL, cytosolic [Ca2+]i, the levels of LDH and CK, pyroptosis-related proteins and CaSR in H9c2 cells. We further researched the mechanisms of CaSR-mediated pyroptosis in the H/R+HRF model by CaSR-shRNA, Ac-YVAD-CMK, MCC950 and NAC. Results: We found that HRF significantly increased CaSR expression, rate of cell death, levels of CK and LDH, and exacerbated pyroptosis in MI/R model. In vitro, HRF increased CaSR expression, decreased viability, enhanced cytosolic [Ca2+]i and exacerbated pyroptosis in H/R cells. Pretreated with GdCl3 worsen these changes, and NPS2143, MCC950, Ac-YVAD-CMK, NAC and sh-CaSR can reversed these effects. Conclusion: Exposure to HRF for a short time exacerbates MI/R-induced injury by targeting CaSR to increase cytosolic [Ca2+]i and ROS levels, which mediate the NLRP3 inflammasome and pyroptosis.


Assuntos
Traumatismo por Reperfusão Miocárdica , Traumatismo por Reperfusão , Animais , Ratos , Inflamassomos/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Receptores de Detecção de Cálcio/metabolismo , Remifentanil , Traumatismo por Reperfusão/metabolismo
4.
Inflamm Res ; 71(10-11): 1327-1345, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35962798

RESUMO

BACKGROUND AND OBJECTIVE: Acute lung injury (ALI)/ acute respiratory distress syndrome (ARDS) was increasingly recognized as one of the most severe acute hyperimmune response of coronavirus disease 2019 (COVID-19). Clofazimine (CFZ) has attracted attention due to its anti-inflammatory property in immune diseases as well as infectious diseases. However, the role and potential molecular mechanism of CFZ in anti-inflammatory responses remain unclear. METHODS: We analyze the protein expression profiles of CFZ and LPS from Raw264.7 macrophages using quantitative proteomics. Next, the protective effect of CFZ on LPS-induced inflammatory model is assessed, and its underlying mechanism is validated by molecular biology analysis. RESULTS: LC-MS/MS-based shotgun proteomics analysis identified 4746 (LPS) and 4766 (CFZ) proteins with quantitative information. The key proteins and their critical signal transduction pathways including TLR4/NF-κB/HIF-1α signaling was highlighted, which was involved in multiple inflammatory processes. A further analysis of molecular biology revealed that CFZ could significantly inhibit the proliferation of Raw264.7 macrophages, decrease the levels of TNF-α and IL-1ß, alleviate lung histological changes and pulmonary edema, improve the survival rate, and down-regulate TLR4/NF-κB/HIF-1α signaling in LPS model. CONCLUSION: This study can provide significant insight into the proteomics-guided pharmacological mechanism study of CFZ and suggest potential therapeutic strategies for infectious disease.


Assuntos
Lesão Pulmonar Aguda , Tratamento Farmacológico da COVID-19 , Síndrome do Desconforto Respiratório , Animais , Camundongos , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Cromatografia Líquida , Clofazimina , Lipopolissacarídeos/farmacologia , Pulmão/patologia , NF-kappa B/metabolismo , Proteômica , Espectrometria de Massas em Tandem , Receptor 4 Toll-Like/metabolismo
5.
Inorg Chem ; 61(44): 17646-17652, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36282019

RESUMO

Endohedral open-cage fullerenes are one of the attractive types of fullerenes due to their interesting electronic properties which make it potentially promising for applications in molecular electronics. In this paper, a novel structure of Na+···Cl-@C50N5H5 with Na+ inside the cavity and Cl- at the opening of the open-cage fullerene is designed to explore the chemical bonding and interaction between the open-cage fullerene system C50N5H5 and NaCl salt. Further, the directional migration of Na+ was achieved by applying an external electric field (EEF) along the X-axis. Notably, when the EEF ranges from -85 to -86 × 10-4 au, Na+ sharply approaches Cl- to regain its ionic bonding character. In addition, the Wiberg bond index, electron localization function topological analysis, and interaction energy (Eint) of the structure under the effect of the EEF also experienced a series of interesting changes. We hope that this work will provide a new strategy for the design of innovative materials for molecular electronics.

6.
Nanotechnology ; 33(45)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35850036

RESUMO

CsPbX3(X = Cl, Br, I) semiconductor nanocrystals (NCs) have excellent optical and photoelectric properties, and are potential core materials for various photoelectric devices. However, the toxicity of Pb and instability have been the key limitations to application of NCs. Herein, using MnBr2and MnBr2·4H2O as manganese sources, heavy Mn-doped CsPbBr3(Mn:CsPbBr3) NCs are synthesized by high-energy ball grinding, which avoids high temperature, a large number of polar solvents and atmosphere protection required in traditional liquid phase methods. However, when MnBr2·4H2O is used as the raw material, infinite solid solution doping can be achieved, and the synthesized Mn:CsPbBr3NCs show smaller particle size, stronger PL intensity and stability. The reason is that presence of crystal water plays a similar role to wet milling in the ball milling process, and can promote the passivation effect of oleylamine (OAm) on nanocrystal defects and the connection between them. In addition, a simple, easy-operating and beneficial to commercial production method for the preparation of Mn:CsPbBr3NCs/EVA flexible films is proposed, which can effectively improve the stability of Mn:CsPbBr3NCs. This study is expected to provide an effective way for the synthesis and stability improvement of CsPbX3NCs doped with different ions.

7.
Exp Cell Res ; 404(2): 112579, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33957117

RESUMO

Anti-angiogenic therapy represents one of the most promising treatment modalities for human cancers. However, the response to antiangiogenic therapy in gastric cancer (GC) remains dismal. To help identify new strategies for antiangiogenic therapy in GC, we evaluated miR-205-5p expression in GC tissues from TCGA database and our hospital, and its functions in angiogenesis were explored in vitro and in vivo. We investigated miR-205-5p expression and microvessel densities (MVDs) in GC tissues and liver metastases from patients. The function and mechanisms of miR-205-5p were examined in human cell lines and in xenograft mouse models. Associations between miR-205-5p expression and clinical characteristics were analyzed using either Pearson's χ2 test or Fisher's exact test. Differences in overall survival (OS) distributions were evaluated using the log-rank test. Differences in measurement data were compared using Student's t-test and one-way ANOVA. We found that miR-205-5p expression was downregulated in GC tissues and was negatively correlated with CD31 expression in both TCGA and our clinical samples. GC cell lines expressed low levels of miR-205-5p, and miR-205-5p upregulation significantly impaired the proliferation and angiogenesis of GC cells. Moreover, vascular endothelial growth factor A (VEGFA) and fibroblast growth factor 1 (FGF1) expression and activation of extracellular-related kinase (ERK) signaling were suppressed by miR-205-5p. MiR-205-5p inhibition promoted malignant phenotypes by enhancing VEGFA and FGF1 expression, as well as the activation of ERK signaling. Angiogenesis and ERK signaling were decreased in response to VEGFA and FGF1 downregulation induced by miR-205-5p overexpression. The dual-luciferase reporter assay showed that VEGFA and FGF1 were direct targets of miR-205-5p. Xenograft mouse models revealed that miR-205-5p suppressed tumor growth by inhibiting neovascularization. Altogether, these results demonstrate that miR-205-5p suppresses angiogenesis in GC by attenuating the expression of VEGFA and FGF1, indicating that upregulation of miR-205-5p may represent as an antiangiogenic therapy for GC.


Assuntos
MicroRNAs/genética , Neovascularização Patológica/genética , Neoplasias Gástricas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética
8.
Opt Lett ; 46(17): 4398-4401, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470025

RESUMO

Recently, terahertz (THz)-driven particle accelerators have drawn increasing attention. The development of high-energy-gain THz accelerators on chip has been a challenge. Here we propose a concept of an on-chip THz-driven particle accelerator that uses few-cycle THz pulses to drive dielectric prisms. It avoids the serious waveguide dispersion of previous THz linacs based on dielectric lined waveguides and enhances the electron-energy gain. In addition, we propose to use prism stacks to overcome the asynchronization effect when accelerating low-energy particles, by which a longer acceleration length with even higher energy gain can be realized. Compared with the available on-chip dielectric laser accelerators, the proposed scheme avoids serious dielectric dispersion and enhances accelerated bunch charge. Hence, it promises an attractive particle accelerator on chip.

9.
Inorg Chem ; 60(16): 12049-12058, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34313129

RESUMO

The design of artificial receptors with a specific recognition function and enhanced selectivity is highly desirable in the electrochemical sensing field, which can be used for detection of environmental pollutants. In this facet, metal-organic frameworks (MOFs) featured adjustable porosities and specific host-guest recognition properties. Especially, the large hydrophobic cavity formed in the porous MOFs may become a potential artificial receptor. We herein designed a new porous MOF [Zn2(L)(IPA)(H2O)]·2DMF·2MeOH·3H2O (Zn-L-IPA) by using a functionalized sulfonylcalix[4]arene (L1) and isophthalic acid (H2IPA) (DMF = N,N'-dimethylformamide). The specific pore size and pore shape of Zn-L-IPA made it efficiently selective for absorption of bisphenol A (BPA), bisphenol F (BPF), and bisphenol S (BPS). Therefore, a rapid, highly selective, and ultrasensitive electrochemical sensing platform Zn-L-IPA@GP/GCE was fabricated by using Zn-L-IPA as a host to recognize and absorb bisphenol guests (GP = graphite powder, GCE = glassy carbon electrode). Most strikingly, the extremely low detection limits were up to 3.46 and 0.17 nM for BPA and BPF, respectively, using the Zn-L-IPA@GP/GCE electrode. Furthermore, the "recognition and adsorption" mechanism was uncovered by density functional theory with the B3LYP function. This work offered a prospective strategy for selective absorption and detection of harmful bisphenols with the MOF-based porous material.

10.
Nanotechnology ; 32(1): 015706, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33043907

RESUMO

Photocatalytic degradation of pollutants has been proved to be an effective strategy for wastewater treatment. Herein, TiO2 nanoparticles were synthesized on a Ti3C2 matrix by in situ growth, forming Z-scheme TiO2@Ti3C2/Cd0.5Zn0.5S (TO/CZS) multilevel structured nanocomposites via one-step hydrothermal route. The effects of hydrothermal temperature and Cd0.5Zn0.5S content on microstructure and properties of composites were assessed. TO/CZS nanocomposites were probed into phase composition, morphological and optical properties with x-ray diffractometer, infrared radiation, scanning electron microscope and UV-vis reflective spectra. Following the hydrothermal reaction at 160 °C for 12 h, TiO2 nanoparticles of 30 nm in diameter were generated in situ on Ti3C2 lamina and Cd0.5Zn0.5S particles were evenly distributed on the Ti3C2 matrix. The photocatalytic activity of TO/CZS composites were evaluated, which found that degradation rate constant (k = 0.028 min-1) of TO/CZS-40 on Rhodamine B was 5.19 times that of pure TiO2 and 4.48 times that of Cd0.5Zn0.5S. Through anchoring Ti3C2 as an electron transition mediator and combination with TiO2 and Cd0.5Zn0.5S, the new Z-scheme between TiO2 oxidized by Ti3C2 and Cd0.5Zn0.5S establishes a multilevel structure of separating electron-hole pairs. This work demonstrates a valid way to control electrons and hole transfer directions efficiently through designing multilevel semiconductor structural designs.

11.
Nanotechnology ; 32(35)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-33984850

RESUMO

Oxygen reduction reaction (ORR) occupies a pivotal position in fuel cell applications, and it is a challenge to obtain highly durable ORR catalysts. Herein, porous cobalt oxide microsphere growing at the surface of on nitrogen-doped graphitized-nano-diamond (CoOx/N-GND) was prepared using hydrothermal and subsequent heat treatment process. Porous cobalt oxide of high specific surface area could expose more surface Co2+that act as active sites than bulk one does. The doping of nitrogen also promotes the catalytic activity. Besides, nano-diamond (ND) ofsp3hybrid structure was used as an electronic conduction carriers of ultrahigh stability to improve the durability of catalytic composite. Prepared CoOx/N-GND shows a satisfactory half-wave potential of 0.82 V (versus RHE), which is close to that of Pt/C (0.85 V), an excellent methanol tolerance and a lower activity loss after 5000 cycles. These merits inspire the application of CoOx/N-GND as the cathode of Zn-air battery and the battery performance was evaluated in this work. In general, this work highlights an innovate approach to design and prepare highly durable catalyst.

12.
Bioorg Med Chem ; 50: 116476, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34757244

RESUMO

Succinate dehydrogenase inhibitors (SDHIs) have become one of the fastest growing classes of new fungicides since entering the market, and have attracted increasing attention as a result of their unique structure, high activity and broad fungicidal spectrum. The mechanism of SDHIs is to inhibit the activity of succinate dehydrogenase, thereby affecting mitochondrial respiration and ultimately killing pathogenic fungi. At present, they have become popular varieties researched and developed by major pesticide companies in the world. In the review, we focused on the mechanism, the history, the representative varieties, structure-activity relationship and resistance of SDHIs. Finally, the potential directions for the development of SDHIs were discussed. It is hoped that this review can strengthen the individuals' understanding of SDHIs and provide some inspiration for the development of new fungicides.


Assuntos
Inibidores Enzimáticos/farmacologia , Fungicidas Industriais/farmacologia , Succinato Desidrogenase/antagonistas & inibidores , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Fungicidas Industriais/síntese química , Fungicidas Industriais/química , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Succinato Desidrogenase/metabolismo
13.
Phys Chem Chem Phys ; 23(41): 23998-24003, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34664046

RESUMO

Phenalenyl (PLY) and its derivatives could form one-dimensional π-aggregates through pancake π-π bonding, which would lead to exotic optoelectronic properties. We will highlight the key aspects of the PLY derivatives from the design strategies to exploration of the electronic properties. Here, we primarily construct alternating boron (B)- and nitrogen (N)-doped PLY π-aggregates: dimer[12], trimer[12-1], trimer[12-2], tetramer[12]2, pentamer[12]2-1, pentamer[12]2-2, and hexamer[12]3. The geometric and electronic structures show that the short intermolecular distances of the π-aggregates drive the formation of pancake π-π bonding. Significantly, the molecular structures show periodic changes in the π-aggregates, but the first hyperpolarizabilities (ßtot) present unexpected changes, which are found to increase sharply with increasing even layer thickness due to intermolecular charge transfer. The ßtot value of hexamer[12]3 (5.72 × 104 a.u.) is 6.4 times that of tetramer[12]2 (8.95 × 103 a.u.), and is 22.4 times that of dimer[12] (2.55 × 103 a.u.). Thus, constructing π-aggregates can significantly improve the second-order NLO response, which is mainly due to intermolecular charge transfer through pancake π-π bonding of the interlayers.

14.
Exp Cell Res ; 393(2): 112089, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32439493

RESUMO

MicroRNAs (miRNAs) are reported to involve in pathogenesis of temporal lobe epilepsy (TLE). miR-142-5p is found increased in TLE, but its role remains unknown. In the study, we established a mouse model of status epilepticus (SE) with pilocarpine and a cell model of TLE. Quantitative real-time PCR revealed an up-regulation of miR-142-5p and down-regulation of mitochondrial Rho 1 (Miro1) in the mouse mode of SE. Administration of miR-142-5p antagomirs via intracerebroventricular injection attenuated pilocarpine-induced SE and hippocampal damage, and alleviated mitochondrial dysfunction along with increased mitochondrial membrane potential and intracellular ATP and Ca (2+) levels. The expression of mitochondrial trafficking kinesin protein (Trak) 1 and Trak2 was up-regulated by inhibiting miR-142-5p. Antagomirs targeting miR-142-5p suppressed pilocarpine-induced oxidative stress as evidenced by decreased ROS generation and MPO activity, and increased SOD activity. Silencing miR-142-5p reduced neuronal death in pilocarpine-treated hippocampus and magnesium-free (MGF)-treated neurons. Inhibition of miR-142-5p decreased cytoplasmic Cytochrome C and increased mitochondrial Cytochrome C, reduced cleaved-caspase3 and Bax levels, and elevated Bcl2 in vivo and in vitro. Further, dual-luciferase assay verified Miro1 as a target of miR-142-5p, suggesting that miR-142-5p might function via targeting Mrio1. Depletion of Miro1 inhibited the protective effect of silencing miR-142-5p on hippocampal neurons in vitro. Taken together, down-regulation of miR-142-5p via targeting Miro1 inhibits neuronal death and mitochondrial dysfunction, and thus attenuates pilocarpine-induced SE, suggesting the potential involvement of miR-142-5p in the pathogenesis of TLE.


Assuntos
Antagomirs/metabolismo , Antagomirs/farmacologia , MicroRNAs/genética , Estado Epiléptico/metabolismo , Animais , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/efeitos dos fármacos , Neurônios/metabolismo , Pilocarpina/metabolismo , Pilocarpina/farmacologia , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/patologia , Regulação para Cima/efeitos dos fármacos
15.
J Am Chem Soc ; 142(27): 11791-11803, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32520550

RESUMO

We present a theoretical design of the singlet-fission (SF) interconversion between two hydrogen tautomers to attract attention to electronic devices such as switches in the SF field. We develop a tuned π-electron conjugation strategy based on single-hydrogen migration to introduce diradical character and yield low-lying E(T1) levels. Specifically, these objectives could be accomplished by moving one hydrogen from a dihydrogen-substituted pyrazine-fused ring to another unsubstituted pyrazine-fused ring in tetraazatetracenes. The predicted SF efficiency would be expected to exceed 120%. To guide future SF design development, one rule of thumb regarding the S0-state and T1-state emerges from our research: In the S0-state, single-hydrogen migration is crucial for effectively localized electrons, which are the key factor in the formation of diradicals. Conversely, single-hydrogen migration induces a large area of π-electron conjugation in the T1-state, which is completely applied to the electron-hole interaction in the S0 → T1 transition, thereby providing low-lying E(T1) levels. Furthermore, a series of hydrogen tautomers of tetraazaacenes have been proposed as diradicaloid SF switches to verify the reliability of the above rule of thumb. This study will not only help researchers in the photovoltaic field to obtain the desired E(T1) in the future but also broaden the application of hydrogen migration in photovoltaic switch research and supplement the SF database.

16.
Int J Neurosci ; 130(12): 1192-1198, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32064983

RESUMO

Background: Recessive mutations in ETFDH gene have been associated with Multiple Acyl-CoA dehydrogenase deficiency (MADD). The late-onset MADD is often muscle involved, presenting with lipid storage myopathy (LSM). The symptoms of LSM were heterogeneous and definite diagnosis of this disease depends on the pathology and gene test.Methods: Neurological examination, muscle biopsy, and MRI examinations were performed in a patient with a novel missense ETFDH mutation.Results: We describe a patient with lipid storage myopathy complicated with skin damage. In addition, the next generation revealed a novel missense mutation (c.970G > T, p.Val324Leu) in exon 8, which was predicted to be a disease-causing mutation by Mutation-taster, and destroy the function of the protein by Sift.Conclusion: These findings expand the known mutational spectrum of ETFDH and phenotype of MADD.


Assuntos
Flavoproteínas Transferidoras de Elétrons/genética , Erros Inatos do Metabolismo Lipídico , Deficiência Múltipla de Acil Coenzima A Desidrogenase , Distrofias Musculares , Riboflavina/farmacologia , Pele/patologia , Complexo Vitamínico B/farmacologia , Humanos , Erros Inatos do Metabolismo Lipídico/diagnóstico , Erros Inatos do Metabolismo Lipídico/tratamento farmacológico , Erros Inatos do Metabolismo Lipídico/genética , Erros Inatos do Metabolismo Lipídico/patologia , Deficiência Múltipla de Acil Coenzima A Desidrogenase/diagnóstico , Deficiência Múltipla de Acil Coenzima A Desidrogenase/tratamento farmacológico , Deficiência Múltipla de Acil Coenzima A Desidrogenase/genética , Deficiência Múltipla de Acil Coenzima A Desidrogenase/patologia , Distrofias Musculares/diagnóstico , Distrofias Musculares/tratamento farmacológico , Distrofias Musculares/genética , Distrofias Musculares/patologia , Mutação de Sentido Incorreto , Riboflavina/administração & dosagem , Complexo Vitamínico B/administração & dosagem
17.
Hum Genet ; 138(7): 749-756, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31079202

RESUMO

Cytochrome c oxidase 20 (COX20)/FAM36A encodes a conserved protein that is important for the assembly of COX, complex IV of the mitochondrial respiratory chain. A homozygous mutation (p.Thr52Pro) in COX20 gene has been previously described to cause muscle hypotonia and ataxia. In this study, we describe two patients from a non-consanguineous family exhibiting autosomal recessive sensory-dominant axonal neuropathy and static encephalopathy. The whole-exome sequencing analysis revealed that both patients harbored compound heterozygous mutations (p.Lys14Arg and p.Trp74Cys) of COX20 gene. The pathogenicity of the variants was further supported by morphological alternations of mitochondria observed in sural nerve and decreased COX20 protein level of peripheral blood leucocytes derived from the patients. In conclusion, COX20 might be considered as a candidate gene for the complex inherited disease. This observation broadens the clinical and genetic spectrum of COX20-related disease. However, due to the limitation of a single-family study, additional cases and studies are definitely needed to further confirm the association.


Assuntos
Encefalopatias/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Deformidades do Pé/genética , Neuropatia Axonal Gigante/genética , Mutação , Adolescente , Adulto , Encefalopatias/patologia , Feminino , Deformidades do Pé/patologia , Neuropatia Axonal Gigante/patologia , Humanos , Masculino , Adulto Jovem
18.
Ann Surg ; 269(6): 1092-1100, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31082907

RESUMO

OBJECTIVE: The aim of this study was to test whether the perioperative composition of intestinal microbiota can contribute to variable outcomes following vertical sleeve gastrectomy (VSG). SUMMARY OF BACKGROUND DATA: Although bariatric surgery is the most effective treatment for obesity, metabolic outcomes are variable. METHODS: Diet-induced obese mice were randomized to VSG or sham surgery, with or without exposure to antibiotics that selectively suppress mainly gram-positive (fidaxomicin, streptomycin) or gram-negative (ceftriaxone) bacteria on postoperative days (POD) 1-4. Fecal microbiota was characterized before surgery and on POD 7 and 28. Mice were metabolically characterized on POD 30-32 and euthanized on POD 35. RESULTS: VSG resulted in weight loss and shifts in the intestinal microbiota composition relative to sham-operated mice. Antibiotic exposure resulted in sustained reductions in alpha (within-sample) diversity of microbiota and shifts in its composition. All antibiotic treatments proved to be detrimental to metabolic VSG outcomes, regardless of antimicrobial specificity of antibiotics. These effects involved functionally distinct pathways. Specifically, fidaxomicin and streptomycin markedly altered hepatic bile acid signaling and lipid metabolism, while ceftriaxone resulted in greater reduction of key antimicrobial peptides. However, VSG mice exposed to antibiotics, regardless of their specificity, had significantly increased subcutaneous adiposity and impaired glucose homeostasis without changes in food intake relative to control VSG mice. CONCLUSION: Dysbiosis induced by brief perioperative antibiotic exposure attenuates weight loss and metabolic improvement following VSG. Potential mechanisms include disruption of bile acid homeostasis and reduction in the production of gut antimicrobial peptides. Results of this study implicate the intestinal microbiota as an important contributor to metabolic homeostasis and a potentially modifiable target influencing clinical outcomes following VSG.


Assuntos
Antibacterianos/uso terapêutico , Gastrectomia , Microbioma Gastrointestinal/efeitos dos fármacos , Obesidade/cirurgia , Redução de Peso , Animais , Ceftriaxona/uso terapêutico , Modelos Animais de Doenças , Fidaxomicina/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Obesidade/microbiologia , Estreptomicina/uso terapêutico , Falha de Tratamento
19.
J Comput Chem ; 40(19): 1772-1779, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30942507

RESUMO

Usually, an extra catalyst (for example, the transition metal complexes) need to be used in catalyzing hydroboration, which involved the cost, environment, and so forth. Here, a greener and controllable catalyst-external electric field (EEF) was used to study its effect on hydroboration of N-(4-methylbenzyl)aniline (PhN═CHPhMe) with pinacolboane (HBPin). The results demonstrated that EEF could affect the barrier heights of both two pathways of this reaction. More significantly, flipping the direction of EEF could modify the reaction mechanism to induce a dominant inverse hydroboration at some field strength. That is to say, oriented EEF is a controlling switch for the anti- or Markovnikov hydroboration reaction of imines. This investigation is meaningful for the exploration of greener catalyst for chemistry reaction and guide a new method for the Markovnikov hydroboration addition. © 2019 Wiley Periodicals, Inc.

20.
Chemphyschem ; 20(14): 1879-1884, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31124269

RESUMO

The nature of the 2e/12c bond and its conversion to a carbon-carbon single bond in phenalenyl dimers have prompted a great deal of interests recently. In this work, we theoretically investigated a series of π-stacking phenalenyl derivatives with 2e/12c bonding character by density functional theory (DFT) calculations to elucidate origin of this unusual bond conversion. Results show that bond-conversion of the phenalenyl dimer easily occurs at room-temperature both dynamically and thermodynamically. However, bond-conversion of hetero π-stacking adducts, in which the two center carbon atoms were substituted by boron and nitrogen atoms, respectively, is much more difficult, because the 2e/12c bond is stabilized by its charge transfer character. Consequently, the bond-conversion is an endothermic process, albeit with a low conversion barrier. Interestingly, Lewis acid-base interactions would be induced by substitution of the center nitrogen atom to phosphorus atom. The 2e/12c bond is further stabilized by 5.9 kcal mol-1 and its conversion is also thermodynamically unfavorable.

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