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1.
Proc Natl Acad Sci U S A ; 120(24): e2220867120, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37279265

RESUMO

The mammalian cochlear epithelium undergoes substantial remodeling and maturation before the onset of hearing. However, very little is known about the transcriptional network governing cochlear late-stage maturation and particularly the differentiation of its lateral nonsensory region. Here, we establish ZBTB20 as an essential transcription factor required for cochlear terminal differentiation and maturation and hearing. ZBTB20 is abundantly expressed in the developing and mature cochlear nonsensory epithelial cells, with transient expression in immature hair cells and spiral ganglion neurons. Otocyst-specific deletion of Zbtb20 causes profound deafness with reduced endolymph potential in mice. The subtypes of cochlear epithelial cells are normally generated, but their postnatal development is arrested in the absence of ZBTB20, as manifested by an immature appearance of the organ of Corti, malformation of tectorial membrane (TM), a flattened spiral prominence (SP), and a lack of identifiable Boettcher cells. Furthermore, these defects are related with a failure in the terminal differentiation of the nonsensory epithelium covering the outer border Claudius cells, outer sulcus root cells, and SP epithelial cells. Transcriptome analysis shows that ZBTB20 regulates genes encoding for TM proteins in the greater epithelial ridge, and those preferentially expressed in root cells and SP epithelium. Our results point to ZBTB20 as an essential regulator for postnatal cochlear maturation and particularly for the terminal differentiation of cochlear lateral nonsensory domain.


Assuntos
Cóclea , Células Ciliadas Auditivas , Animais , Camundongos , Cóclea/metabolismo , Células Ciliadas Auditivas/fisiologia , Audição/fisiologia , Mamíferos , Gânglio Espiral da Cóclea , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
J Am Chem Soc ; 146(28): 19019-19029, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38963153

RESUMO

Photocatalysis has emerged as an effective tool for addressing the contemporary challenges in organic synthesis. However, the trial-and-error-based screening of feasible substrates and optimal reaction conditions remains time-consuming and potentially expensive in industrial practice. Here, we demonstrate an electrochemical-based data-acquisition approach that derives a simple set of redox-relevant electro-descriptors for effective mechanistic analysis and performance evaluation through machine learning (ML) in photocatalytic synthesis. These electro-descriptors correlate to the quantification of shifted charge transfer processes in response to the photoirradiation and enabled construction of reactivity diagram where high-yield reactive "hot zones" can reflect subtle changes of the reaction system. For the model reaction of photocatalytic deoxygenation reaction, the influence of varying carboxylic acids (substrate A, oxidation-intended) and alkenes (substrate B, reduction-intended) and varying reaction conditions on the reaction yield can be visualized, while mathematical analysis of the electro-descriptor patterns further revealed distinct mechanistic/kinetic impacts from different substrates and conditions. Additionally, in the application of ML algorithms, the experimentally derived electro-descriptors reflect an overall redox kinetic outcome contributed from vast reaction parameters, serving as a capable means to reduce the dimensionality in the case of complex multiparameter chemical space. As a result, utilization of electro-descriptors enabled efficient and robust quantitative evaluation of chemical reactivity, demonstrating promising potential of introducing operando-relevant experimental insights in the data-driven chemistry.

3.
Mol Genet Genomics ; 299(1): 88, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39313603

RESUMO

Nanog is a crucial regulatory factor in maintaining the self-renewal and pluripotency of embryonic stem cells. It is involved in various biological processes, such as early embryonic development, cell reprogramming, cell cycle regulation, the proliferation and migration of primordial germ cells. While research on this gene has primarily focused on mammals, there has been a growing interest in studying nanog in fish. However, there is a notable lack of comprehensive reviews regarding this gene in fish, which is essential for guiding future research. This review aims to provide a thorough summary of the gene's structure, expression patterns, functions and regulatory mechanisms in fish. The findings suggest that nanog probably has both conserved and divergent functions in regulating cell pluripotency, early embryonic development, and germ cell development in teleosts compared to other species, including mammals. These insights lay the foundation for future research and applications of the nanog gene, providing a new perspective for understanding the evolution and conserved charactristics of teleost nanog.


Assuntos
Proteínas de Peixes , Peixes , Proteína Homeobox Nanog , Animais , Desenvolvimento Embrionário/genética , Células-Tronco Embrionárias/metabolismo , Evolução Molecular , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Células-Tronco Pluripotentes/metabolismo
4.
BMC Cardiovasc Disord ; 24(1): 521, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333846

RESUMO

BACKGROUND: New-onset atrial fibrillation (NOAF) is a common adverse outcome in acute ST-segment elevation myocardial infarction (STEMI) patients following percutaneous coronary intervention (PCI) and is associated with a worse prognosis. The platelet-to-albumin ratio (PAR) has been utilized to predict the severity and prognosis of cardiovascular diseases. This study aims to investigate the predictive value of PAR combined with the C2HEST score for NOAF in the elderly population with STEMI undergoing PCI. METHODS: 445 elderly STEMI patients without a history of atrial fibrillation (AF) who underwent PCI were consecutively enrolled in this study. Multivariate logistic regression analysis was used to identify independent risk factors for NOAF after PCI. RESULTS: 50 patients (11.2%) developed NOAF after PCI. Multivariate logistic regression analysis revealed that heart rate (HR), systemic immune-inflammation index (SII), uric acid (UA), PAR, and C2HEST score were independent risk factors for NOAF. The area under the curve (AUC) of the combined PAR and C2HEST score was 0.839, and Delong's test indicated that the combined model had superior predictive value compared to individual markers (AUC of PAR: 0.738; AUC of C2HEST score: 0.752) (P < 0.05). The addition of PAR and C2HEST score to this model (HR, SII, and UA) significantly improved the reclassification and discrimination ability (IDI 0.175; NRI 0.734, both P < 0.001). During regular follow-up, the incidence of MACE was higher in the NOAF group compared to the non-NOAF group. CONCLUSION: The combination of PAR and the C2HEST score has a high predictive value for NOAF in elderly STEMI patients following PCI.


Assuntos
Fibrilação Atrial , Biomarcadores , Plaquetas , Intervenção Coronária Percutânea , Valor Preditivo dos Testes , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/sangue , Fibrilação Atrial/fisiopatologia , Masculino , Feminino , Idoso , Intervenção Coronária Percutânea/efeitos adversos , Fatores de Risco , Medição de Risco , Biomarcadores/sangue , Plaquetas/metabolismo , Resultado do Tratamento , Fatores Etários , Albumina Sérica Humana/análise , Idoso de 80 Anos ou mais , Contagem de Plaquetas , Técnicas de Apoio para a Decisão , Estudos Retrospectivos , Pessoa de Meia-Idade , Fatores de Tempo
5.
Angew Chem Int Ed Engl ; : e202415223, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39343763

RESUMO

Dual-single-atom catalysts (DSACs) are the next paradigm shift in single-atom catalysts because of the enhanced performance brought about by the synergistic effects between adjacent bimetallic pairs. However, there are few methods for synthesizing DSACs with precise bimetallic structures. Herein, a pre-coordination strategy is proposed to precisely synthesize a library of DSACs. This strategy ensures the selective and effective coordination of two metals via phthalocyanines with specific coordination sites, such as -F- and -OH-. Subsequently, in-situ confinement inhibits the migration of metal pairs during high-temperature pyrolysis, and obtains the DSACs with precisely constructed metal pairs. Despite changing synthetic parameters, including transition metal centers, metal pairs, and spatial geometry, the products exhibit similar atomic metal pairs dispersion properties, demonstrating the universality of the strategy. The pre-coordination strategy synthesized DSACs shows significant CO2 reduction reaction performance in both flow-cell and practical rechargeable Zn-CO2 batteries. This work not only provides new insights into the precise synthesis of DSACs, but also offers guidelines for the accelerated discovery of efficient catalysts.

6.
Small ; 19(25): e2301128, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36919799

RESUMO

Electrochemical CO2 reduction reaction (CO2 RR), powered by renewable electricity, has attracted great attention for producing high value-added fuels and chemicals, as well as feasibly mitigating CO2 emission problem. Here, this work reports a facile hard template strategy to prepare the Ni@N-C catalyst with core-shell structure, where nickel nanoparticles (Ni NPs) are encapsulated by thin nitrogen-doped carbon shells (N-C shells). The Ni@N-C catalyst has demonstrated a promising industrial current density of 236.7 mA cm-2 with the superb FECO of 97% at -1.1 V versus RHE. Moreover, Ni@N-C can drive the reversible Zn-CO2 battery with the largest power density of 1.64 mW cm-2 , and endure a tough cycling durability. These excellent performances are ascribed to the synergistic effect of Ni@N-C that Ni NPs can regulate the electronic microenvironment of N-doped carbon shells, which favor to enhance the CO2 adsorption capacity and the electron transfer capacity. Density functional theory calculations prove that the binding configuration of N-C located on the top of Ni slabs (Top-Ni@N-C) is the most thermodynamically stable and possess a lowest thermodynamic barrier for the formation of COOH* and the desorption of CO. This work may pioneer a new method on seeking high-efficiency and worthwhile electrocatalysts for CO2 RR and Zn-CO2 battery.

7.
Future Oncol ; 19(15): 1063-1072, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37283023

RESUMO

Aim: To evaluate independent risk factors specific for early-stage nasopharyngeal carcinoma (NPC). Methods: A total of 566 patients with early-stage NPC from 2004 to 2019 were identified using the Surveillance, Epidemiology and End Results database. Results: Older ages (70-79 and >80 years) were independent risk factors, with hazard ratios of 1.961 and 5.011, respectively. The hazard ratio for early-stage NPC in Asian and Pacific Islander residents (0.475) was lower than that for White residents. A tumor size <3 cm was a protective factor for overall and cancer-specific survival in the current study. Conclusion: In patients with early-stage NPC, age >70 years, race and tumor size were independent prognosticators for cancer-specific survival.


Assuntos
Neoplasias Nasofaríngeas , Humanos , Estados Unidos/epidemiologia , Idoso , Carcinoma Nasofaríngeo/patologia , Prognóstico , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/terapia , Modelos de Riscos Proporcionais , Fatores de Risco , Estadiamento de Neoplasias
8.
Chin Med Sci J ; 38(1): 66-69, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36727414

RESUMO

Both anti-glomerular basement membrane (GBM) disease and the anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) are common causes of pulmonary-renal syndrome. Organizing pneumonia (OP), a special pattern of interstitial lung disease, is extremely rare either in AAV or anti-GBM disease. We report an old woman presented with OP on a background of co-presentation with both ANCA and anti-GBM antibodies.


Assuntos
Doença Antimembrana Basal Glomerular , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Glomerulonefrite , Pneumonia em Organização , Pneumonia , Feminino , Humanos , Anticorpos Anticitoplasma de Neutrófilos , Autoanticorpos , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações
9.
Angew Chem Int Ed Engl ; 62(25): e202303868, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37086028

RESUMO

The atom- and step-efficient synthesis of chiral fused tricyclic lactams from readily available ketoesters using cheap ammonium salts as the nitrogen source is reported. This ruthenium-catalyzed system operates through an efficient tandem dynamic kinetic asymmetric reductive amination (ARA)/lactamization and produces chiral fused tricyclic lactams in high yields with excellent diastereo- and enantioselectivity (up to >99 % ee, >20 : 1 dr and 98 % yield). The robust method was also applied to the concise synthesis of key intermediates in the synthesis of rivastigmine analogues and chiral N-heterocyclic carbene catalysts.


Assuntos
Compostos de Amônio , Lactamas , Aminação , Sais , Catálise
10.
J Am Chem Soc ; 144(39): 17763-17768, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36166275

RESUMO

Due to their low reactivity, difficult enantiocontrol, and proneness to N-O bond cleavage, the catalytic asymmetric hydrogenation of oximes to hydroxylamines has remained a significant challenge. Herein, a Lewis and Brønsted acid cooperation strategy was established for the asymmetric hydrogenation of oximes, providing the corresponding hydroxylamines with up to 95% yield and up to 96% ee. Addition of Lewis and Brønsted acid was crucial to obtain high conversion and enantioselectivity. Mechanistic investigations indicates that the thiourea fragment of the ligand, Lewis acid (In(OTf)3 or Zn(OAc)2), as well as the Brønsted acid (l-CSA) played vital roles in the control of reactivity and enantioselectivity of the reaction. In addition, the synthetic elaboration of this transformation was demonstrated by gram scale experiment with retention of the yield and enantioselectivity.


Assuntos
Ácidos de Lewis , Oximas , Hidrogenação , Ligantes , Estereoisomerismo , Tioureia
11.
J Am Chem Soc ; 144(33): 15185-15192, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35948416

RESUMO

Selective oxidation to synthesize nitriles is critical for feedstock manufacturing in the chemical industry. Current strategies typically involve substitutions of alkyl halides with toxic cyanides or the use of strong oxidation reagents (oxygen or peroxide) under ammoxidation/oxidation conditions, setting considerable challenges in energy efficiency, sustainability, and production safety. Herein, we demonstrate a facile, green, and safe electrocatalytic route for selective oxidation of amines to nitriles under ambient conditions, assisted by the anodic water oxidation on metal-doped α-Ni(OH)2 (a typical oxygen evolution reaction catalyst). By controlling the balance between co-adsorption of the amine molecule and hydroxyls on the catalyst surface, we demonstrate that Mn doping significantly promotes the subsequent chemical oxidation of amines, resulting in Faradaic efficiencies of 96% for nitriles under ≥99% conversion. This anodic oxidation is further coupled with cathodic hydrogen evolution for overall atomic economy and additional green energy production.

12.
J Musculoskelet Neuronal Interact ; 22(4): 546-561, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36458392

RESUMO

OBJECTIVE: To evaluate the mechanism of Bone Marrow Mesenchymal Stem Cells (BMSCs) in regulating NF-κB signal pathway by targeting miR-449a. METHODS: Stem cells were transfected by over-expressing and inhibiting miR-449a to detect the levels and viability of miR-449a in stem cells after transfection. Stem cells and neurons were co-cultured in vitro to evaluate the in vitro mechanism of stem cells over-expressing miR-449a on neurons. RESULTS: After the addition of neurons, the neuronal activity of miR-449a over-expression group increased significantly, the expression of NF-κB signal pathway proteins (IκBα, p50, and p65) decreased, and the inflammatory cytokines (TNF-α and IL-1ß) decreased significantly (P<0.05). In vivo experiments in rats also showed that rats were unresponsive, did not chirp or elude after being stimulated. After stem cell therapy, the weight and response of rats gradually returned to normal levels. miR-449a expression significantly increased in the stem cell + miR-449a over-expression group, expression of NF-κB signal pathway proteins (IκBα, p50, and p65) decreased, inflammatory cytokines (TNF-α and IL-1ß) significantly decreased, and cell activity significantly increased (P<0.05). CONCLUSIONS: BMSCs can modulate NF-κB signaling pathway by targeting miR-449a, so as to reduce the inflammatory response to peripheral nerve injury and repair nerve injury.


Assuntos
Células-Tronco Mesenquimais , MicroRNAs , Traumatismos dos Nervos Periféricos , Animais , Ratos , Citocinas , MicroRNAs/genética , NF-kappa B , Inibidor de NF-kappaB alfa , Transdução de Sinais , Fator de Necrose Tumoral alfa
13.
Appl Opt ; 61(6): C13-C19, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-35200993

RESUMO

Spatial heterodyne scanning imaging combines the advantages of spatial heterodyne spectroscopy and imaging technology. It can obtain images and spectral information simultaneously with the characteristics of high spectral resolution, high flux, and small volume and can achieve spectral restoration of all target points in the measured area through scan imaging only once. When two-dimensional spatial information and one-dimensional spectral information are obtained, the imaging spectrum data cube is generated. Using MATLAB and ZEMAX as simulation software, image information with interference fringes was constructed, and the distribution of interference information was explored. A potassium lamp, xenon lamp, and tungsten lamp were used as different light sources to perform validation. Because of the influence of the scanning displacement error on the accuracy of interference information extraction, an algorithm for image spectrum reconstruction is proposed based on the principle of distribution of interference information. The speed-up robust features algorithm was used for image registration to improve accuracy. The experimental results show that the spectral information under the three light sources can be reconstructed, which corresponds to the standard spectrum from the optical fiber spectrometer. The feasibility of this imaging spectrum reconstruction has been preliminarily verified, and the spectral information of the desired target can be directly extracted from the data cube.

14.
Neural Plast ; 2022: 5114721, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304208

RESUMO

Neurofeedback (NFB) is a relatively novel approach to the treatment of tinnitus, and prior studies have demonstrated that the increases in alpha activity rather than reduced delta power seem to drive these NFB-related improvements in tinnitus symptoms. The present study was therefore designed to explore whether the implementation of an alpha training protocol with a portable neurofeedback apparatus would achieve improvements in tinnitus patient symptoms. In this study, 38 tinnitus patients underwent NFB training while 18 were enrolled in a control group. The study was single-blinded such that only participants were not aware of their group assignments. Those in the NFB group underwent 15 NFB training sessions over 5 weeks, in addition to pre- and posttraining tests including the Tinnitus Handicap Inventory (THI), Tinnitus Handicap Questionnaire (THQ), visual analog scales (VAS), electroencephalography (EEG), and functional magnetic resonance imaging (fMRI). Our result find that when the THI, THQ, and VAS scores of patients in the two groups were assessed after a 5-week training period, these scores were unchanged in control patients whereas they had significantly improved in the NFB group patients. EEG analyses revealed that the alpha band was increased in the occipital lobe following NFB treatment, while fMRI indicated an increase in regional homogeneity (ReHo) in the right frontal lobe of patients in the NFB group after treatment that was negatively correlated with THI and VAS scores. The results of this analysis indicate that alpha NFB training can be effectively used to reduce tinnitus-related distress and sound perception in patients.


Assuntos
Neurorretroalimentação , Zumbido , Humanos , Eletroencefalografia , Imageamento por Ressonância Magnética , Neurorretroalimentação/métodos , Medição da Dor , Zumbido/diagnóstico por imagem , Zumbido/terapia , Método Simples-Cego
15.
Eur Arch Otorhinolaryngol ; 279(6): 2791-2801, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34255147

RESUMO

PURPOSE: To demonstrate our experience in the treatment of petrous bone cholesteatoma (PBC). METHODS: Data of PBC patients in our hospital from January 2000 to December 2019 were collected. Surgical approaches and facial function were mainly discussed and compared with the literature. The management of 2 giant PBC cases affecting rhinopharynx has been demonstrated. RESULTS: The supralabyrinthine type was the most frequent type followed by the massive type. There were 5 cases with cholesteatoma extending into the clivus (2 cases), sphenoid (1 case) and rhinopharynx (2 cases). The translabyrinthine approach (40%) was our most frequently used approach followed by the middle fossa approach (36%) and the transmastoid approach (11%). There were 10 cases managed with the assistance of endoscope, including 3 cases with cholesteatoma extending into clivus, sphenoid and rhinopharynx separately. Obliteration of the cavity was performed in 70.3% (135/192) cases; 3 of them recurred. For the 2 giant PBC cases affecting rhinopharynx, traditional microscopic surgery assisted with transnasal endoscope was performed. The reduced exposure was beneficial for postoperative recovery, and the approach in the nasal cavity provided a permanent drainage for postoperative examination. CONCLUSION: Otologic endoscope combined with traditional microscopic surgery could reduce the exposure in surgery. For extremely extended cases of PBC, supplementary transnasal endoscopic approach deserves to be considered for the traditional temporal bone approach.


Assuntos
Colesteatoma , Osso Petroso , Colesteatoma/cirurgia , Fossa Craniana Posterior/cirurgia , Endoscopia , Humanos , Nasofaringe , Osso Petroso/cirurgia
16.
Chem Soc Rev ; 50(5): 3211-3237, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33480901

RESUMO

This review provides a comprehensive view of the application of first-row transition metals in asymmetric hydrogenation and asymmetric transfer hydrogenation. The catalytic behavior of 3d metals is significantly different from that of 4d and 5d metals. The replacement of noble metals with first-row transition metals has encountered challenges such as different reaction mechanisms and unexpected deactivation of the catalyst. The potential involvement of a single-electron process has been the most notorious feature of first-row metals. This review aims to give readers a picture of how first-row transition metals catalyze hydrogenation reactions and the corresponding enantioinduction models. Although this article is partitioned according to the substrate type, it is mechanism-oriented and is focused on catalytic systems. A certain catalytic system could be applied in the hydrogenation of different types of double bonds. Similarities within first-row metals and differences from their 4d and 5d congeners were emphasized.

17.
J Am Chem Soc ; 143(6): 2477-2483, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33529522

RESUMO

A catalytic protocol for the enantio- and diastereoselective reduction of α-substituted-ß-keto carbonitriles is described. The reaction involves a DKR-ATH process with the simultaneous construction of ß-hydroxy carbonitrile scaffolds with two contiguous stereogenic centers. A wide range of α-substituted-ß-keto carbonitriles were obtained in high yields (94%-98%) and excellent enantio- and diastereoselectivities (up to >99% ee, up to >99:1 dr). The origin of the diastereoselectivity was also rationalized by DFT calculations. Furthermore, this methodology offers rapid access to the pharmaceutical intermediates of Ipenoxazone and Tapentadol.

18.
Ann Bot ; 127(7): 853-864, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-33035305

RESUMO

BACKGROUND AND AIMS: Theory predicts that outcrossing should be more prevalent among perennials than annuals, a pattern confirmed by comparative evidence from diverse angiosperm families. However, intraspecific comparisons between annual and perennial populations are few because such variation is uncommon among flowering plants. Here, we test the hypothesis that perennial populations outcross more than annual populations by investigating Incarvillea sinensis, a wide-ranging insect-pollinated herb native to China. The occurrence of both allopatric and sympatric populations allows us to examine the stability of mating system differences between life histories under varying ecological conditions. METHODS: We estimated outcrossing rates and biparental inbreeding in 16 allopatric and five sympatric populations in which both life histories coexisted using 20 microsatellite loci. In each population we measured height, branch number, corolla size, tube length and herkogamy for ~30 individuals. In a sympatric population, we recorded daily flower number, pollinator visitation and the fruit and seed set of annual and perennial plants. KEY RESULTS: As predicted, outcrossing rates (t) were considerably higher in perennial (mean = 0.76) than annual (mean = 0.09) populations. This difference in mating system was also maintained at sympatric sites where plants grew intermixed. In both allopatric and sympatric populations the degree of herkogamy was consistently larger in outcrossing than selfing plants. Perennials were more branched, with more and larger flowers than in annuals. In a sympatric population, annuals had a significantly higher fruit and seed set than perennials. CONCLUSIONS: Genetically based differences in herkogamy between annuals and perennials appear to play a key role in governing outcrossing rates in populations, regardless of variation in local ecological conditions. The maintenance of mating system and life history trait differentiation between perennial and annual populations of I. sinensis probably results from correlated evolution in response to local environmental conditions.


Assuntos
Flores , Reprodução , Animais , Flores/genética , Endogamia , Insetos , Polinização , Sementes
19.
J Enzyme Inhib Med Chem ; 36(1): 1079-1087, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34030574

RESUMO

Inhibitors of COMT are clinically used for the treatment of Parkinson's disease. Here, we report the first natural pentacyclic triterpenoid-type COMT inhibitors and their structure-activity relationships and inhibition mechanism. The most potent compounds were found to be oleanic acid, betulinic acid and celastrol with IC50 values of 3.89-5.07 µM, that acted as mixed (uncompetitive plus non-competitive) inhibitors of COMT, representing a new skeleton of COMT inhibitor. Molecular docking suggested that they can specifically recognise and bind with the unique hydrophobic residues surrounding the catechol pocket. Furthermore, oleanic acid and betulinic acid proved to be less disruptive of mitochondrial membrane potential (MMP) compared to tolcapone, thus reducing the risk of liver toxicity. These findings could be used to produce an ideal lead compound and to guide synthetic efforts in generating related derivatives for further preclinical testing.


Assuntos
Produtos Biológicos/farmacologia , Catecol O-Metiltransferase/metabolismo , Inibidores Enzimáticos/farmacologia , Triterpenos Pentacíclicos/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Cinética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Conformação Molecular , Simulação de Acoplamento Molecular , Triterpenos Pentacíclicos/síntese química , Triterpenos Pentacíclicos/química , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
20.
Int J Mol Sci ; 22(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34769185

RESUMO

Laccases can catalyze the remediation of hazardous synthetic dyes in an eco-friendly manner, and thermostable laccases are advantageous to treat high-temperature dyeing wastewater. A novel laccase from Geothermobacter hydrogeniphilus (Ghlac) was cloned and expressed in Escherichia coli. Ghlac containing 263 residues was characterized as a functional laccase of the DUF152 family. By structural and biochemical analyses, the conserved residues H78, C119, and H136 were identified to bind with one copper atom to fulfill the laccase activity. In order to make it more suitable for industrial use, Ghlac variant Mut2 with enhanced thermostability was designed. The half-lives of Mut2 at 50 °C and 60 °C were 80.6 h and 9.8 h, respectively. Mut2 was stable at pH values ranging from 4.0 to 8.0 and showed a high tolerance for organic solvents such as ethanol, acetone, and dimethyl sulfoxide. In addition, Mut2 decolorized approximately 100% of 100 mg/L of malachite green dye in 3 h at 70 °C. Furthermore, Mut2 eliminated the toxicity of malachite green to bacteria and Zea mays. In summary, the thermostable laccase Ghlac Mut2 could effectively decolorize and detoxify malachite green at high temperatures, showing great potential to remediate the dyeing wastewater.


Assuntos
Lacase/química , Engenharia de Proteínas , Corantes de Rosanilina/química , Águas Residuárias/química , Biodegradação Ambiental , Estabilidade Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Lacase/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
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