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1.
Small ; 20(22): e2308514, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38098438

RESUMO

Highly robust flexible multifunctional film with excellent electromagnetic interference shielding and electrothermal/photothermal characteristics are highly desirable for aerospace, military, and wearable devices. Herein, an asymmetric gradient multilayer structured bacterial cellulose@Fe3O4/carbon nanotube/Ti3C2Tx (BC@Fe3O4/CNT/Ti3C2Tx) multifunctional composite film is fabricated with simultaneously demonstrating fast Joule response, excellent EMI shielding effectiveness (EMI SE) and photothermal conversion properties. The asymmetric gradient 6-layer composite film with 40% of Ti3C2Tx possesses excellent mechanical performance with exceptional tensile strength (76.1 MPa), large strain (14.7%), and good flexibility. This is attributed to the asymmetric gradient multilayer structure designed based on the hydrogen bonding self-assembly strategy between Ti3C2Tx and BC. It achieved an EMI SE of up to 71.3 dB, which is attributed to the gradient "absorption-reflection-reabsorption" mechanism. Furthermore, this composite film also exhibits excellent low-voltage-driven Joule heating (up to 80.3 °C at 2.5 V within 15 s) and fast-response photothermal performance (up to 101.5 °C at 1.0 W cm-2 within 10 s), which is attributed to the synergistic effect of heterostructure. This work demonstrates the fabrication of multifunctional bacterial cellulose@Fe3O4/carbon nanotube/Ti3C2Tx composite film has promising potentials for next-generation wearable electronic devices in energy conversion, aerospace, and artificial intelligence.


Assuntos
Celulose , Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Celulose/química , Nanotubos de Carbono/química , Titânio/química , Bactérias , Nanocompostos/química
2.
Cell Biol Int ; 48(2): 154-161, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37920124

RESUMO

Alopecia areata (AA) is a complex genetic disease that results in hair loss due to an autoimmune-mediated attack on the hair follicle. Mesenchymal stem cells (MSCs) have great potential to induce hair regeneration due to their strong secretion ability and multidirectional differentiation. Recent studies have revealed that the therapeutic potential of MSCs comes from their secretion ability, which can produce large amounts of bioactive substances and regulate the key physiological functions of subjects. The secretion products of MSCs, such as vesicles, exosomes, and conditioned media, have significant advantages in preparing of biological products derived from stem cells. Human umbilical cord mesenchymal stem cells (uMSCs) are the best choice for exosome production. uMSCs are obtained from the human umbilical cord. The umbilical cord is easy to obtain, and the efficiency of uMSCs isolation and culture higher than that of obtaining MSCs from bone marrow or adipose tissue. In this study, we investigated the effects of exosomes released from uMSCs in AA mice. In summary, due to easy isolation and cultivation, simple preparation, and convenient storage, it is possible to obtain uMSCs, or uMSCs exosomes for research and clinical treatment.


Assuntos
Alopecia em Áreas , Exossomos , Células-Tronco Mesenquimais , Humanos , Camundongos , Animais , Alopecia em Áreas/terapia , Cabelo , Cordão Umbilical , Proliferação de Células , Queratinócitos
3.
Endocr Pract ; 30(2): 177-186, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38007181

RESUMO

OBJECTIVE: We aimed to evaluate the effects of thyroid-stimulating hormone (TSH) suppression therapy on cardiac structure and function in patients with differentiated thyroid cancer (DTC) following thyroidectomy. METHODS: Two investigators independently searched the PubMed, Embase, Cochrane Library, and Web of Science databases for relevant studies published from inception to January 6, 2023, without any restrictions on language. Standard mean differences and 95% confidence intervals were calculated using fixed or random effects models. Thirteen clinical outcomes were analyzed, mainly evaluating cardiac morphology, systolic function, and diastolic function. RESULTS: Thirteen studies were included in the quantitative analysis. Compared to healthy controls, left ventricular mass index, left ventricular posterior wall thickness, interventricular septal thickness, and isovolumic relaxation time values increased; the ratio of E-wave velocity to A-wave velocity and E-wave velocity values decreased. The left ventricular ejection fraction and cardiac output did not change in patients with DTC who underwent long-term TSH suppression therapy. Interventricular septal thickness values were significantly correlated with the duration of TSH suppression therapy. CONCLUSION: Long-term TSH suppression therapy leads to cardiac hypertrophy and impaired cardiac diastolic function in patients with DTC. These changes may be related to the duration of TSH suppression therapy. Large prospective studies with long follow-up periods are needed to validate these findings.


Assuntos
Neoplasias da Glândula Tireoide , Tiroxina , Humanos , Tiroxina/uso terapêutico , Volume Sistólico , Tireoidectomia , Estudos Prospectivos , Tireotropina , Função Ventricular Esquerda , Neoplasias da Glândula Tireoide/cirurgia
4.
Aesthetic Plast Surg ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811386

RESUMO

BACKGROUND: Chest deformity is a potential complication associated with auricular reconstruction using autologous costal cartilage. The impact of the incision size employed for costal cartilage harvesting on chest deformities remains unclear. This study aimed to investigate the correlation between the incision size used for harvesting costal cartilage and the occurrence of chest deformities. METHODS: We retrospectively analyzed patients who underwent ear reconstruction using autologous costal cartilage between June 2021 and September 2022. The patients were categorized into two groups based on the size of the costal cartilage incision: large and small. Chest computed tomography (CT) was performed 18-24 months postoperatively, followed by three-dimensional color map quantification to assess the degree of asymmetry of the chest surface. Subsequently, quantitative data analysis was performed to compare the extent of chest asymmetry between the large- and small-incision groups. The Visual Analog Scale (VAS) was used to assess patient satisfaction with chest morphology. RESULTS: This study included 62 patients, with an equal distribution of 31 in each group. The mean asymmetry value of the small and large incision groups was -3.15 ± 1.88 and -5.27 ± 3.63, respectively. Moreover, the mean VAS score for the small and large incision groups was 7.48 ± 0.72 and 5.09 ± 0.94, respectively. Statistically significant differences were observed between the two groups. CONCLUSIONS: Small incision costal cartilage harvesting can effectively alleviate the severity of chest deformities and significantly enhance patient satisfaction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

5.
BMC Genomics ; 24(1): 531, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679709

RESUMO

BACKGROUND: Due to the influence of extreme weather, the environment in China's main cotton-producing areas is prone to drought stress conditions, which affect the growth and development of cotton and lead to a decrease in cotton yield. RESULTS: In this study, 188 upland cotton germplasm resources were phenotyped for data of 8 traits (including 3 major yield traits) under drought conditions in three environments for two consecutive years. Correlation analysis revealed significant positive correlations between the three yield traits. Genetic analysis showed that the estimated heritability of the seed cotton index (SC) under drought conditions was the highest (80.81%), followed by that of boll weight (BW) (80.64%) and the lint cotton index (LC) (70.49%) With genome-wide association study (GWAS) analysis, a total of 75 quantitative trait loci (QTLs) were identified, including two highly credible new QTL hotspots. Three candidate genes (Gh_D09G064400, Gh_D10G261000 and Gh_D10G254000) located in the two new QTL hotspots, QTL51 and QTL55, were highly expressed in the early stage of fiber development and showed significant correlations with SC, LC and BW. The expression of three candidate genes in two extreme materials after drought stress was analyzed by qRT-PCR, and the expression of these two materials in fibers at 15, 20 and 25 DPA. The expression of these three candidate genes was significantly upregulated after drought stress and was significantly higher in drought-tolerant materials than in drought-sensitive materials. In addition, the expression levels of the three candidate genes were higher in the early stage of fiber development (15 DPA), and the expression levels in drought-tolerant germplasm were higher than those in drought-sensitive germplasm. These three candidate genes may play an important role in determining cotton yield under drought conditions. CONCLUSIONS: This study is helpful for understanding the regulatory genes affecting cotton yield under drought conditions and provides germplasm and candidate gene resources for breeding high-yield cotton varieties under these conditions.


Assuntos
Secas , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Melhoramento Vegetal , Gossypium/genética
6.
Respir Res ; 24(1): 113, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37061713

RESUMO

BACKGROUND: Centromere protein O (CENPO) is a newly discovered constitutive centromeric protein, associated with cell death. However, little is known about how CENPO expression is associated with human cancers or immune infiltration. Here, we assessed the function of CENPO in pan-cancer and further verified the results in lung adenocarcinoma (LUAD) through in vitro and in vivo experiments. METHODS: Sangerbox and TCGA databases were used to evaluate the CENPO expression level in different human cancer types. A subsequent evaluation of the potential role of CENPO as a diagnostic and prognostic biomarker in pancancer was conducted. The CENPO mutations were analyzed using the cBioPortal database and its function was analyzed using the LinkedOmics and CancerSEA databases. The TIMER2 and TISIDB websites were used to find out how CENPO affects immune infiltration. The expression level of CENPO in LUAD was revealed by TCGA database and immunohistochemical (IHC) staining. Targetscan, miRWalk, miRDB, miRabel, LncBase databases, and Cytoscape tool were used to identify microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) that regulate expression and construct ceRNA network. Subsequently, loss-of-function assays were performed to identify the functions of CENPO on the malignant behavior and tumor growth of LUAD in vitro and in vivo experiments. RESULTS: In most cancers, CENPO was upregulated and mutated, which predicted a poorer prognosis. Furthermore, infiltration of CENPO and myeloid-derived suppressor cells (MDSC) showed a significant positive correlation, while T-cell NK infiltration showed a significant negative correlation in most cancers. CENPO was expressed at high levels in LUAD and was correlated with p-TNM stage. Furthermore, CENPO knockdown suppressed the malignant phenotypes of LUAD cells, manifested by slower proliferation, cycle in G2, increased apoptosis, decreased migration, and attenuated tumorigenesis. Furthermore, CENPO knockdown decreased CDK1/6, PIK3CA, and inhibited mTOR phosphorylation, suggesting that the mTOR signaling pathway may be involved in CENPO-mediated regulation of LUAD development. CONCLUSIONS: In pan-cancer, especially LUAD, CENPO may be a potential biomarker and oncogene. Furthermore, CENPO has been implicated in immune cell infiltration in pan-cancer and represents a potential immunotherapeutic target for tumor therapy.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , Humanos , Carcinogênese , Morte Celular , Óxidos N-Cíclicos , Neoplasias Pulmonares/genética , Prognóstico , Proteínas Cromossômicas não Histona
7.
Folia Phoniatr Logop ; 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37788662

RESUMO

OBJECTIVE: The study aimed to investigate the mechanisms of impairment and recovery in graph naming functions among patients with aphasia due to cerebral infarction. Specifically, the study compared immediate effects of transcranial Direct Current Stimulation (tDCS) treatment in patients at different stages post-infarction: the acute phase and the recovery period. METHODS: Twenty-eight patients were selected, consisting of 16 in the acute phase (AP) and 12 in the recovery period (RP), along with 18 healthy controls. Both patient groups underwent two weeks of tDCS treatment. Post-treatment changes in functional connectivity (FC) within language-related brain regions, as well as in graph naming abilities, were assessed in both patient groups. RESULTS: Both AP and RP groups exhibited significant improvements in graph naming ability following tDCS treatment. Compared to healthy controls, patients showed decreased functional connectivity in multiple brain regions of both hemispheres, particularly in the dominant hemisphere. Post-treatment assessments revealed significant increases in functional connectivity within the bilateral frontotemporal lobes for both AP and RP groups, and within the bilateral temporo-occipital regions for the AP group. Moreover, the RP group demonstrated decreased functional connectivity in the left temporal lobe post-treatment, which had shown increased functional connectivity pre-treatment. CONCLUSIONS: This study suggests that tDCS can effectively enhance graph naming functions in patients with post-infarction aphasia. The therapeutic effects appear to be mediated by enhancing functional connectivity within bilateral frontotemporal lobes.

8.
Angew Chem Int Ed Engl ; 62(49): e202313817, 2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-37852936

RESUMO

An epoxycyclohexenone (ECH) moiety occurs in natural products of both bacteria and ascomycete and basidiomycete fungi. While the enzymes for ECH formation in bacteria and ascomycetes have been identified and characterized, it remained obscure how this structure is biosynthesized in basidiomycetes. In this study, we i) identified a genetic locus responsible for panepoxydone biosynthesis in the basidiomycete mushroom Panus rudis and ii) biochemically characterized PanH, the cytochrome P450 enzyme catalyzing epoxide formation in this pathway. Using a PanH-producing yeast as a biocatalyst, we synthesized a small library of bioactive ECH compounds as a proof of concept. Furthermore, homology modeling, molecular dynamics simulation, and site directed mutation revealed the substrate specificity of PanH. Remarkably, PanH is unrelated to ECH-forming enzymes in bacteria and ascomycetes, suggesting that mushrooms evolved this biosynthetic capacity convergently and independently of other organisms.


Assuntos
Agaricales , Ascomicetos , Basidiomycota , Agaricales/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Biocatálise , Basidiomycota/genética , Ascomicetos/metabolismo , Bactérias/metabolismo , Especificidade por Substrato
9.
Appl Opt ; 61(12): 3502-3509, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35471448

RESUMO

Bessel beams have nondiffraction and self-healing properties in the propagation direction and are widely used in particle optical manipulation and optical microscopy. Bessel beams can be generated by axicons or spatial light modulators, which can produce a zero-order or high-order Bessel beam with different parameters depending on the specific application. The modulation of Bessel beams achieved in the spatial spectrum domain by optimization algorithms has a low light energy utilization rate due to the small effective modulation region. We propose a Bessel-like beam phase generation algorithm based on an improved iterative optimization algorithm directly in the spatial domain to achieve a tunable modulation of the beam's length and the axial center position. The optimization time is reduced from minutes to seconds relative to the genetic algorithm, providing a new means of modulation for different applications in various fields.

10.
Aesthetic Plast Surg ; 46(1): 406-418, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34341856

RESUMO

BACKGROUND: Botulinum toxin (BoNT) injection is the most commonly performed procedure in cosmetic surgery. However, blind injection is unable to take individual anatomical variations into consideration, which is the main contributing factor to complications. Ultrasound (US) imaging was introduced to reduce complications and improve effects. This article will review uses of US in aesthetic BoNT injection. METHOD: A systematic electronic search was performed using the PubMed, MEDLINE, Web of science. Search terms were set to focus on aesthetic BoNT injection. Two independent reviewers subsequently reviewed the resultant articles based on strict inclusion and exclusion criteria. Selected manuscripts were analysed and grouped by procedure categories. Clinical cases were all performed by one plastic surgeon in our department. RESULTS: The search finally retained 24 articles. Five procedural categories were identified, including masseter (n = 16), frontalis (n = 2), glabella complex (n = 2), trapezius (n=1), and gastrocnemius (n = 3). US imaging is practical and instructive for pre-operative assessments as in needle-type selection, injection point localization and depth setting, as well as post-operative follow-ups regarding injection feedback (for instance, the extent of muscle volume decreases). What's more, ultrasound-guided injection makes needle trajectory visualized so as for the needle to reach the target muscle in avoidance of potential damage to neurovascular bundle, gland or adjacent muscle. CONCLUSION: Muscles, such as masseter, frontalis, glabella complex, trapezius and gastrocnemius, and their adjacent structures can be well visualized using US, and as such, US can be a useful tool for a variety of pre-operative, intra-operative and post-operative procedures. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Toxinas Botulínicas Tipo A , Músculos Superficiais do Dorso , Estética , Testa , Humanos , Ultrassonografia
11.
Opt Express ; 29(4): 6158-6168, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33726142

RESUMO

Light-sheet fluorescence microscopy (LSFM) facilitates high temporal-spatial resolution, low photobleaching and phototoxicity for long-term volumetric imaging. However, when a high axial resolution or optical sectioning capability is required, the field of view (FOV) is limited. Here, we propose to generate a large FOV of light-sheet by scanning multiple focus-shifted Gaussian beam arrays (MGBA) while keeping the high axial resolution. The positions of the beam waists of the multiple Gaussian beam arrays are shifted in both axial and lateral directions in an optimized arranged pattern, and then scanned along the direction perpendicular to the propagation axis to form an extended FOV of light-sheet. Complementary beam subtraction method is also adopted to further improve axial resolution. Compared with the single Gaussian light-sheet method, the proposed method extends the FOV from 12 µm to 200 µm while sustaining the axial resolution of 0.73 µm. Both numerical simulation and experiment on samples are performed to verify the effectiveness of the method.

12.
Anticancer Drugs ; 32(2): 127-137, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33417325

RESUMO

Gastric cancer is one of the most common malignant tumors. MicroRNA-196b (miR-196b) has been demonstrated to play important roles in human cancers. However, its functions in gastric cancer progression were still largely unknown. In this study, the expression of miR-196b was determined by quantitative real-time PCR. Esophageal cancer-related gene 4 (ECRG4) level was examined by western blot assay and immunohistochemistry staining assay. Cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8) assay and colony formation assay. Cell migration and invasion were analyzed by transwell assay. The association between miR-196b and ECRG4 was analyzed by dual-luciferase reporter assay. The functional role of miR-196b in vivo was analyzed by murine xenograft assay. As a result, we found the expression of miR-196b was elevated and the protein expression of ECRG4 was reduced in gastric cancer tissues and cells. MiR-196b inhibition suppressed gastric cancer cell proliferation, migration and invasion. ECRG4 was a target of miR-196b and its protein expression was negatively regulated by miR-196b. Moreover, ECRG4 overexpression showed similar effects with miR-196b inhibition on the malignant behaviors of GC cells and ECRG4 knockdown reversed the effects of miR-196b inhibition on gastric cancer cell proliferation, migration and invasion. In addition, miR-196b inhibition suppressed tumor volume and weight in vivo. In conclusion, downregulation of miR-196b inhibited gastric cancer progression by modulating ECRG4 expression, indicating that miR-196b might be a potential therapeutic target for gastric cancer.


Assuntos
MicroRNAs/biossíntese , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Proteínas Supressoras de Tumor/biossíntese , Idoso , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
13.
Chem Biodivers ; 18(7): e2001047, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34000082

RESUMO

Triple-negative breast cancer (TNBC) makes up 15 % to 20 % of all breast cancer (BC) cases, and represents one of the most challenging malignancies to treat. For many years, chemotherapy has been the main treatment option for TNBC. Natural products isolated from marine organisms and terrestrial organisms with great structural diversity and high biochemical specificity form a compound library for the assessment and discovery of new drugs. In this review, we mainly focused on natural compounds and extracts (from marine and terrestrial environments) with strong anti-TNBC activities (IC50 <100 µM) and their possible mechanisms reported in the past six years (2015-2021).


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos/farmacologia , Extratos Vegetais/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Neoplasias de Mama Triplo Negativas/patologia
14.
Org Biomol Chem ; 18(30): 5850-5856, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32692341

RESUMO

Natural products (NPs) and their derivatives play a pivotal role in drug discovery due to their complexity and diversity. The strategies to rapidly generate NP-like compounds offer unique opportunities to access bioactive compounds. Here we present a new approach, precursor-assisted biosynthesis (PAB), for the creation of NP-like compounds by combination of artificial supplementation of common precursors and divergent post-modifications of precursor-deficient fungi. This method was applied to construct a meroterpenoid-like compound collection containing 43 compounds with diverse molecular scaffolds. Extensive bioactive screening of the collection revealed novel STING (stimulator of interferon genes) inhibitors, cytotoxic and antifungal compounds. This result indicates that PAB is an effective methodology for producing compound collections for the purpose of drug discovery.


Assuntos
Produtos Biológicos
15.
Appl Opt ; 59(17): 5131-5135, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32543531

RESUMO

The scattering effect occurring when light passes through inhomogeneous-refractive-index media such as atmosphere or biological tissues will scramble the light wavefront into speckles and impede optical imaging. Wavefront shaping is an emerging technique for imaging through scattering media that works by addressing correction of the disturbed wavefront. In addition to the phase and amplitude, the polarization of the output scattered light will also become spatially randomized in some cases. The recovered image quality and fidelity benefit from correcting as much distortion of the scattered light as possible. Liquid-crystal spatial light modulators (LC-SLMs) are widely used in the wavefront shaping technique, since they can provide a great number of controlled modes and thereby high-precision wavefront correction. However, due to the working principle of LC-SLMs, the wavefront correction is restricted to only one certain linear polarization state, resulting in retrieved image information in only the right polarization, while the information in the orthogonal polarization is lost. In this paper, we describe a full-polarization wavefront correction system for shaping the scattered light wavefront in two orthogonal polarizations with a single LC-SLM. The light speckles in both polarizations are corrected for retrieval of the full polarization information and faithful images of objects. As demonstrated in the experiments, the focusing intensity can be increased by full-polarization wavefront correction, images of objects in arbitrary polarization states can be retrieved, and the polarization state of the object's light can also be recognized.

16.
Angew Chem Int Ed Engl ; 59(18): 7209-7213, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32050043

RESUMO

Vibralactone is isolated from the basidiomycete fungus Boreostereum vibrans as one of the strongest lipase inhibitors. Its unusual ß-lactone-fused bicycle is derived from an aryl ring moiety by an oxidative ring-expansion prior to an intramolecular cyclization. Herein, we report the discovery of the cyclase VibC which belongs to the α/ß-hydrolase superfamily and is involved in the vibralactone biosynthesis. Biochemical and crystal studies suggest that VibC may catalyze an aldol or an electrocyclic reaction initiated by the Ser-His-Asp catalytic triad. For the aldol and pericyclic chemistry in living cells, VibC is a unique hydrolase performing the carbocycle formation of an oxepinone to a fused bicyclic ß-lactone. This presents a naturally occurring, new enzymatic reaction in both aldol and hydrolase (bio)chemistry that will guide future exploitation of these enzymes in synthetic biology for chemical-diversity expansion of natural products.


Assuntos
Basidiomycota/química , Produtos Biológicos/metabolismo , Hidrolases/metabolismo , Lactonas/metabolismo , Biocatálise , Produtos Biológicos/química , Cristalografia por Raios X , Ciclização , Hidrolases/química , Lactonas/química , Lactonas/isolamento & purificação , Modelos Moleculares , Estrutura Molecular
17.
Fungal Genet Biol ; 128: 36-42, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30905831

RESUMO

Basidiomycete fungi are a rich source of bioactive diterpenoid secondary metabolites. However, compared with the large number of diterpene synthases (di-TPSs) identified in plants and ascomycete fungi, only three di-TPSs have been described from basidiomycete fungi. Large scale genome sequencing projects combined with the development of synthetic biology techniques now has enabled the rapidly discovery and characterization of di-TPSs from basidiomycete fungi. In this study, we discovered and functionally characterized four di-TPSs from 220 genome sequenced basidiomycete fungi by a combined strategy of genomic data mining, phylogenetic analysis and fast products characterization with synthetic biology techniques. Among them, SteTC1 of Stereum histurum was characterized as the first fungal cembrane diterpene synthase; PunTC of Punctularia strigosozonata and SerTC of Serpula lacrymans were characterized as ent-kauran-16α-ol synthase and DenTC3 of Dentipellis sp was characterized as a cyathane synthase. Our results provide opportunities for the discovery of new diterpenoids from basidiomycete fungi by genome mining.


Assuntos
Basidiomycota/enzimologia , Basidiomycota/genética , Diterpenos/metabolismo , Genoma Fúngico , Biologia Sintética/métodos , Mineração de Dados , Filogenia , Metabolismo Secundário
18.
Appl Opt ; 58(11): 2845-2853, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31044887

RESUMO

Imaging through scattering media has been a long standing challenge in many disciplines. One of the promising solutions to address the challenge is the wavefront shaping technique, in which the phase distortion due to a scattering medium is corrected by a phase modulation device such as a spatial light modulator (SLM). However, the wide-field imaging speed is limited either by the feedback-based optimization to search the correction phase or by the update rate of SLMs. In this report, we introduce a new method called digital holographic wavefront correction, in which the correction phase is determined by a single-shot off-axis holography. The correction phase establishes the so-called "scattering lens", which allows any objects to be imaged through scattering media; in our case, the "scattering lens" is a digital one established through computational methods. As no SLM is involved in the imaging process, the imaging speed is significantly improved. We have demonstrated that moving objects behind scattering media can be recorded at the speed of 2.8 fps with each frame corrected by the updated correction phase while the image contrast is maintained as high as 0.9. The image speed can potentially reach the video rate if the computing power is sufficiently high. We have also demonstrated that the digital wavefront correction method also works when the light intensity is low, which implicates its potential usefulness in imaging dynamic processes in biological tissues.

19.
J Org Chem ; 83(2): 812-822, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29271645

RESUMO

As part of our program to discover new bioactive agents from fungi, 13 new alkaloids accompanying 13 known related alkaloids were isolated from a wild strain of Aspergillus oryzae L1020. Compounds 1 and 2 have unprecedented 6/6/5/7/5 and 6/6/6/5/5 chemical skeletons, representing new members of quinoline alkaloids. Compound 3 is a new macrolactam with an unusual 6/5/6/8 ring system. Compounds 4-13 are new α-cyclopiazonic acid-related alkaloids. The absolute configurations of 1-4, 8, and 9 were assigned by electronic circular dichroism calculations. Compounds 2, 5, 6, 11, 14, 22, and 26 exhibit pronounced neurite outgrowth-promoting effects on PC12 cells in the range of 25-100 µM.


Assuntos
Alcaloides/farmacologia , Aspergillus oryzae/química , Neuritos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Triptofano/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Morte Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Neuritos/metabolismo , Neuritos/patologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Células PC12 , Teoria Quântica , Ratos , Relação Estrutura-Atividade , Triptofano/química , Triptofano/isolamento & purificação
20.
J Nat Prod ; 81(4): 1089-1092, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29553734

RESUMO

Sesterterpenes are usually found in plants and fungi, but are rare in bacteria. Here, we present the identification of StsC from Streptomyces somaliensis, a member of the UbiA superfamily, as a membrane-bound sesterterpene cyclase in bacteria. The cyclized products for StsC, somaliensenes A (1) and B (2), were identified by expressing the corresponding gene in an engineered Escherichia coli strain. The structures of 1 and 2 were determined by analysis of the NMR and MS spectroscopic data.


Assuntos
Sesterterpenos/química , Streptomyces/química , Ciclização , Escherichia coli/química , Espectroscopia de Ressonância Magnética/métodos , Membranas/química
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