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1.
Int J Mol Sci ; 25(16)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39201754

RESUMO

Insects rely on olfaction for mating, finding oviposition sites, and locating hosts. Hyphantria cunea is a serious pest that severely damages forests. Differential expression analysis of olfactory-related genes between males and females is the basis for elucidating the functions of olfactory-related proteins in H. cunea. In this study, Illumina HiSeqTM 4000 high-throughput sequencing technology was used to perform transcriptome sequencing of the antennal tissues of adult male and female H. cunea. Functional annotation was conducted using the NR, Swiss-Prot, KOG, KEGG, and GO databases, and the results showed that the antennal transcriptome of adult H. cunea contained 50,158 unigenes. Differential expression analysis identified 3923 genes that were significantly differentially expressed between male and female antennae. A total of 221 olfactory-related genes were annotated, and 96 sex-biased genes were identified, including 13 odorant receptors (ORs), 48 odorant binding proteins (OBPs), 7 chemosensory proteins (CSPs), 10 ionotropic receptors (IRs), 10 sensory neuron membrane proteins (SNMPs), 2 gustatory receptors (GRs), and 6 odorant-degrading enzymes (ODEs), indicating that there were differences in olfaction between male and female H. cunea. Quantitative real-time PCR was used to verify the expression levels of 21 putative general odorant receptor genes in male and female antennae. HcunOR4 and HcunOR5 showed female-biased expression; HcunOR48, HcunOR49 and HcunOR50 showed male-biased expression. The results were consistent with the transcriptome differential analysis. The screening of male-biased odorant receptor genes might provide a theoretical basis for the functional characterization of odorant receptors for recognizing sex pheromones in H. cunea.


Assuntos
Antenas de Artrópodes , Receptores Odorantes , Transcriptoma , Animais , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Feminino , Masculino , Antenas de Artrópodes/metabolismo , Caracteres Sexuais , Perfilação da Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Anotação de Sequência Molecular
2.
Br J Cancer ; 128(6): 1117-1133, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36631635

RESUMO

BACKGROUND: PIT1-positive pituitary adenoma (PIT1-PA) is one of the most important lineages of pituitary adenoma (PA), which causes systematic endocrine disorders and a worse prognosis. Tumour-associated fibroblast (TAF) is a crucial stroma cell type in the tumour microenvironment (TME). However, cellular and functional heterogeneity of TAF and immune cells in PIT1-PA have not been fully investigated. METHODS: By single-cell RNA sequencing of four PIT1-PAs and further analyses, we characterised the molecular and functional profiles of 28 different cell subtypes. RESULTS: PA stem cells in PIT1/SF1-positve PA were in a hybrid epithelial/mesenchymal state, and differentiated along the PIT1- and SF- dependent branches. C1Q was overwhelmingly expressed in tumour-associated macrophages, indicating its pro-tumoral functionality. PIT1-PA progression was characterised by lower cell-cell communication strength and higher cell adhesion-associated signals, indicating the immunosuppressive but pro-invasive microenvironment. IFN-γ signal repressed functional remodelling of myofibroblastic TAF (mTAF) towards inflammatory TAF/antigen-presenting TAF. IFN-γ inhibited mTAF phenotypes and N-cadherin expression through STAT3 signal axis. CDH2 knockdown in TAFs abrogated their pro-tumour function in PAs. CONCLUSIONS: Our study builds up a cellular landscape of PIT1-PA TME and highlights anti-tumour function of IFN-γ mediated TAF remodelling, which benefits clinical treatments and drug development.


Assuntos
Adenoma , Fibroblastos Associados a Câncer , Neoplasias Hipofisárias , Humanos , Fibroblastos Associados a Câncer/metabolismo , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Microambiente Tumoral , Interferon gama , Adenoma/genética , Fibroblastos/metabolismo
3.
Opt Express ; 31(10): 15537-15552, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157653

RESUMO

A microwave photonic (MWP) radar system with improved signal-to-noise ratio (SNR) performance is proposed and experimentally demonstrated. By improving the SNR of echoes through properly designed radar waveforms and resonant amplification in the optical domain, the proposed radar system can detect and image weak targets that were previously hidden in noise. Echoes with a common low-level SNR obtain high optical gain and the in-band noise is suppressed during resonant amplification. The designed radar waveforms, based on random Fourier coefficients, reduce the effect of optical nonlinearity while providing reconfigurable waveform performance parameters for different scenarios. A series of experiments are developed to verify the feasibility of the SNR improvement of the proposed system. Experimental results show a maximum SNR improvement of 3.6 dB with an optical gain of 28.6 dB for the proposed waveforms over a wide input SNR range. From a comparison with linear frequency modulated signals in microwave imaging of rotating targets, significant quality enhancement is observed. The results confirm the ability of the proposed system to improve SNR performance of MWP radars and its great application potential in SNR-sensitive scenarios.

4.
Opt Express ; 31(2): 2792-2806, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785285

RESUMO

Countless waveguides have been designed based on four basic bends: circular bend, sine/cosine bend, Euler bend (developed in 1744) and Bezier bend (developed in 1962). This paper proposes an n-adjustable (NA) bend, which has superior properties compared to other basic bends. Simulations and experiments indicate that the NA bends can show lower losses than other basic bends by adjusting n values. The circular bend and Euler bend are special cases of the proposed NA bend as n equals 0 and 1, respectively. The proposed bend are promising candidates for low-loss compact photonic integrated circuits.

5.
Acta Neurochir (Wien) ; 165(11): 3255-3266, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697007

RESUMO

PURPOSE: External ventricular drainage (EVD) is a life-saving neurosurgical procedure, of which the most concerning complication is EVD-related infection (ERI). We aimed to construct and validate an ERI risk model and establish a monographic chart. METHODS: We retrospectively analyzed the adult EVD patients in four medical centers and split the data into a training and a validation set. We selected features via single-factor logistic regression and trained the ERI risk model using multi-factor logistic regression. We further evaluated the model discrimination, calibration, and clinical usefulness, with internal and external validation to assess the reproducibility and generalizability. We finally visualized the model as a nomogram and created an online calculator (dynamic nomogram). RESULTS: Our research enrolled 439 EVD patients and found 75 cases (17.1%) had ERI. Diabetes, drainage duration, site leakage, and other infections were independent risk factors that we used to fit the ERI risk model. The area under the receiver operating characteristic curve (AUC) and the Brier score of the model were 0.758 and 0.118, and these indicators' values were similar when internally validated. In external validation, the model discrimination had a moderate decline, of which the AUC was 0.720. However, the Brier score was 0.114, suggesting no degradation in overall performance. Spiegelhalter's Z-test indicated that the model had adequate calibration when validated internally or externally (P = 0.464 vs. P = 0.612). The model was transformed into a nomogram with an online calculator built, which is available through the website: https://wang-cdutcm.shinyapps.io/DynNomapp/ . CONCLUSIONS: The present study developed an infection risk model for EVD patients, which is freely accessible and may serve as a simple decision tool in the clinic.


Assuntos
Drenagem , Adulto , Humanos , Drenagem/efeitos adversos , Procedimentos Neurocirúrgicos , Reprodutibilidade dos Testes , Estudos Retrospectivos
6.
Ecotoxicol Environ Saf ; 260: 115071, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37257345

RESUMO

Biological control is widely used for integrated pest management. However, there are many abiotic factors that can affect the biocontrol efficiency. In this study, we investigated the susceptibility of Hyphantria cunea larvae to Beauveria bassiana under Cd stress, and the corresponding mechanism was analyzed around innate immunity and energy metabolism. The results showed that mortality of H. cunea larvae treated with Cd and B. bassiana was significantly higher than those treated with B. bassiana alone, and the combined lethal effect exhibited a synergistic effect. Compared with the single fungal treatment group, the total hemocyte count in the combined Cd and fungal treatment group decreased significantly, accompanied by a decrease in phagocytosis, encapsulation, and melanization activity. The expression levels of three phagocytosis-related genes, one encapsulation-promoting gene, and one melanization-regulating gene were significantly lower in the combined treatment group than those in the single fungal treatment group. Furthermore, pathogen recognition ability, signal transduction level, and immune effector expression level were weaker in the combined treatment group than those in the single fungal treatment group. The expression levels of 14 key metabolites and 7 key regulatory genes in glycolysis and tricarboxylic acid cycle pathways were significantly lower in the combined treatment group than those in the single fungal treatment group. Taken together, the weakness of innate immunity and energy metabolism in response to pathogen infection resulted in an increased susceptibility of H. cunea larvae to B. bassiana under Cd pre-exposure. Microbial insecticide is a preferred strategy for pest control in heavy metal-polluted areas. AVAILABILITY OF DATA AND MATERIAL: All the data that support the findings of this study are available in the manuscript.


Assuntos
Beauveria , Mariposas , Animais , Larva/genética , Beauveria/fisiologia , Cádmio , Imunidade Inata , Metabolismo Energético
7.
Opt Express ; 30(11): 19731-19744, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36221741

RESUMO

A signal-to-noise ratio (SNR) improvement method for microwave photonic (MWP) links enhanced by optical injection locking (OIL) and channelized spectrum stitching (CSS) is investigated and experimentally demonstrated. By exploiting the resonant amplification characteristics of OIL, both optical gain and in-band noise suppression of the input radio frequency signal can be achieved. The injection bandwidth is channelized to further suppress noise during OIL, and the input signal can be well reconstructed by spectrum stitching in the digital domain. Experimental results show that the optimal improvement in SNR of 3.6 dB is achieved for linear frequency modulated signals and at least an additional improvement of 7.2 dB can be obtained by adopting CSS. Other broadband signals for radar and communication are used to further verify the ability to improve SNR. The potential for application scenarios with large operating bandwidth and high optical gain is also demonstrated.

8.
Cell Biol Int ; 46(10): 1577-1587, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35702760

RESUMO

The current studies associated with tumor biology continue to describe a high correlation between tryptophan (Trp) metabolism and tumor progression. These findings reflect the complex underlying mechanism of tumor development and highlight the need to explore additional drug targets for carcinoma-associated diseases. In our study, we reported that elevated Trp metabolism was observed in highly malignant glioma tumor tissues from patients. The elevated Trp metabolism in glioma cells were induced by the overexpression of Trp 2,3-dioxygenase 2 (TDO2), which further contributed to the production of the metabolite kynurenine (Kyn). Subsequently, the Kyn derived from Trp metabolism was able to mediate the activation of the aryl hydrocarbon receptor (AhR) and downstream PI3K/AKT signals, resulting in the strengthening of tumor stemness and growth. Meanwhile, the activation of the AhR could promote the process of epithelial-mesenchymal transition in gliomas through a TGF-ß-dependent mechanism, leading to enhanced tumor invasion in vitro and in vivo. Inhibition of the AhR using StemRegenin 1 was demonstrated to suppress glioma growth and improve the outcome of traditional chemotherapy in subcutaneous tumor-bearing mice, representing a promising therapeutic target for clinical glioma treatment.


Assuntos
Dioxigenases , Glioma , Animais , Dioxigenases/metabolismo , Glioma/metabolismo , Cinurenina/metabolismo , Cinurenina/farmacologia , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Triptofano/metabolismo , Triptofano Oxigenase/metabolismo
9.
Phytother Res ; 35(7): 4007-4021, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34038010

RESUMO

Pituitary adenoma (PA) is a benign intracranial neoplasm originated from pituitary gland. Surgery is the first-line therapy for most of PAs, but lead to unsatisfactory prognosis in some cases. Tetrandrine (Tet) has anticancer effect on some cancers. However, growth inhibition effect on PA is unknown. To elucidate the inhibitory effect of Tet on the growth of PA and its potential mechanisms, we validated the in vitro and in vivo anti-PA effect of Tet and illustrated the cellular and molecular alterations by confocal microscopy observation, flow cytometry, and RNA interference. Tet inhibited PA cell growth in vitro and tumor progression in vivo. Tet induced autophagy and apoptosis in a dose-dependent manner. Low dosage (1.25 µM) of Tet induced PA cell autophagy by down-regulation of MAPK/STAT3 signal. While, higher dosage (5.0 µM) of Tet partially induced PA cell death through caspase-dependent apoptosis. Autophagy inhibitors enhanced Tet-induced caspase activity and apoptotic cell death. These findings demonstrated that Tet has anti-PA effect by inducing autophagy and apoptosis through MAPK/STAT3 signaling pathway attenuation and autophagy inhibition might enhance its anti-PA effect, indicating that Tet (or combined with autophagy inhibitor) is a potential therapeutic regimen for PAs.


Assuntos
Antineoplásicos Fitogênicos , Benzilisoquinolinas , Neoplasias Hipofisárias , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Benzilisoquinolinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Hipofisárias/tratamento farmacológico , Ratos
10.
Cell Mol Neurobiol ; 40(5): 767-784, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31853695

RESUMO

Exosomes contain plenty of bioactive information, playing an important role in intercellular communication by transfer their bioactive molecular contents to recipient cells. Glioblastoma stem cells (GSCs) and non-GSC glioma cells coexist in GBM microenvironment; GSC-released exosomes contain intracellular signaling molecules, which may affect the biological phenotypes of recipient cells. However, whether GSC exosomes could affect the biological phenotype of non-GSC glioma cells has not yet been defined. To explore whether GSC exosomes could reprogramme non-GSC glioma cells into GSCs and its possible mechanism involved, non-GSC glioma cells were treated with GSCs released exosomes; the potential mechanisms of action were studied with RNA interference, Notch inhibitors and Western blot analysis. The proliferation, neurosphere formation, invasive capacities, and tumorigenicity of non-GSC glioma cells were increased significantly after GSC exosome treatment; Notch1 signaling pathway was activated in GSCs; Notch1 protein was highly enriched in GSC exosomes; Notch1 signaling pathway and stemness-related protein expressions were increased in GSC exosome treated non-GSC glioma cells and these cell generated tumor tissues; Notch1 protein expression in GSCs and their exosomes, and the neurosphere formation of GSCs were decreased by Notch1 RNA interference; Notch1 signaling pathway protein and stemness protein expressions were decreased in GSC exosome treated non-GSC glioma cells by Notch1 RNA interference and Notch inhibitors. The findings in this study indicated that GSC exosomes act as information carriers, mediated non-GSC glioma cell dedifferentiation into GSCs by delivering Notch1 protein through Notch1 signaling activation, and enhanced stemness and tumorigenicity of non-GSC glioma cells.


Assuntos
Neoplasias Encefálicas/patologia , Carcinogênese , Exossomos/metabolismo , Glioblastoma/patologia , Células-Tronco Neoplásicas/patologia , Receptor Notch1/metabolismo , Animais , Testes de Carcinogenicidade , Linhagem Celular Tumoral , Proliferação de Células , Reprogramação Celular , Exossomos/genética , Exossomos/transplante , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Interferência de RNA , Receptor Notch1/genética , Transdução de Sinais , Microambiente Tumoral
11.
Appl Opt ; 59(32): 9985-9994, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33175771

RESUMO

A practical two-dimensional beam steering solid-state system based on the synthesis of one-dimensional wavelength tuning and a one-dimensional optical phased array is demonstrated and investigated. The system incorporates an integrated multiple-channel-interference widely tunable laser, an integrated 32-channel optical phased array, an offline phase error correction unit, and home-made control electronics. The introduction of the integrated tunable laser avoids the traditional bulky light source fed into the optical phased array, making the architecture promising to be miniaturized. In addition, a calibration method based on particle swarm optimization is proposed and proved to be effective to correct the phase errors existing in the arrayed channels and improve the emitted far-field quality. Other practical aspects, such as high-speed control and cost, are taken into the consideration of the system design as well. Under the control of home-made electronics, the laser exhibits a tuning range of 50 nm with a 44 dB side-mode suppression ratio, and the system presents the characteristics of low divergence (0.63∘×0.58∘), high side-lobe suppression ratio (>10dB), and high-speed response (<10µs time constant) in an aliasing-free sweeping range of 18∘×7∘.

12.
Neurosurg Rev ; 43(2): 565-573, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30649647

RESUMO

High-grade meningiomas in ventricles are rare, where most published series only include a few patients. A retrospective analysis was performed on the clinical features, radiological findings, and treatment outcomes of 26 patients with high-grade meningiomas in lateral ventricles who were surgically treated in our hospital between July 2008 and July 2016. A female predilection (female/male = 1.4:1) was observed with a mean age of 42.4 years. Headache and/or vomiting (65.3%) were the most common initial symptom, and with symptom duration time ranging between 7 days and 5 years (mean 8.5 months). The lateral ventricle trigone area was the most common site (80.7%). Twenty-two patients (84.6%) obtained gross total resection. The 2007 WHO classification was used to classify 22 (84.6%) meningiomas as grade II and the remaining four tumors were graded III. These tumors accounted for a recurrence rate of 38.5% (10 of 26 patients) and a mortality rate of 11.5% (3 deaths) during the follow-up periods. The recurrence rate after the gross total resection was 27.3% (6 of 22 patients). Radiotherapy was administered as an adjuvant treatment in 12 patients (46.2%) after surgery. There were 4 recurrences out of the 12 patients who received radiotherapy and 6 of the 14 patients relapsed without radiotherapy (p = 0.58). The subtotal resection was considered a risk factor for recurrence. The postoperative radiotherapy seemed to have little significance for the high-grade meningiomas in the lateral ventricles. Long-term follow-up is required, regardless of the resection grade, and reoperation is feasible for patients with recurrence.


Assuntos
Neoplasias do Ventrículo Cerebral/cirurgia , Ventrículos Laterais/cirurgia , Meningioma/cirurgia , Adolescente , Adulto , Fatores Etários , Idoso , Neoplasias do Ventrículo Cerebral/diagnóstico por imagem , Neoplasias do Ventrículo Cerebral/radioterapia , Terapia Combinada , Feminino , Cefaleia/etiologia , Humanos , Ventrículos Laterais/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Meningioma/diagnóstico por imagem , Meningioma/radioterapia , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia , Estudos Retrospectivos , Fatores Sexuais , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vômito/etiologia , Adulto Jovem
13.
Appl Opt ; 58(13): 3555-3563, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044854

RESUMO

We propose a novel approach to laser frequency noise characterization by delayed self-heterodyne. Compared with the traditional treatment, our method applies to both long and short delay, corresponding to uncorrelated and correlated self-heterodyne. In the case of long delay, it overcomes the influence of 1/f noise on the intrinsic linewidth extraction from a broadened spectrum, and the results are more accurate than Voigt profile fitting. For short delayed correlated heterodyne, it eliminates artifact peaks at multiples of the reciprocal of delay time introduced by transferring measured RF phase noise to laser phase noise, thus extending the measurement range. In addition, it calibrates the frequency noise overestimation caused by a finite noise floor. This method remains valid when the delay and the coherence time are comparable. Experimental results are presented to demonstrate the effectiveness of the proposed approach in characterizing lasers with intrinsic linewidth ranging from sub-100 Hz to megahertz.

14.
Microb Cell Fact ; 17(1): 147, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-30227873

RESUMO

BACKGROUND: Microbial biosynthesis of natural products holds promise for preclinical studies and treating diseases. For instance, pinocembrin is a natural flavonoid with important pharmacologic characteristics and is widely used in preclinical studies. However, high yield of natural products production is often limited by the intracellular cofactor level, including adenosine triphosphate (ATP). To address this challenge, tailored modification of ATP concentration in Escherichia coli was applied in efficient pinocembrin production. RESULTS: In the present study, a clustered regularly interspaced short palindromic repeats (CRISPR) interference system was performed for screening several ATP-related candidate genes, where metK and proB showed its potential to improve ATP level and increased pinocembrin production. Subsequently, the repression efficiency of metK and proB were optimized to achieve the appropriate levels of ATP and enhancing the pinocembrin production, which allowed the pinocembrin titer increased to 102.02 mg/L. Coupled with the malonyl-CoA engineering and optimization of culture and induction condition, a final pinocembrin titer of 165.31 mg/L was achieved, which is 10.2-fold higher than control strains. CONCLUSIONS: Our results introduce a strategy to approach the efficient biosynthesis of pinocembrin via ATP level strengthen using CRISPR interference. Furthermore coupled with the malonyl-CoA engineering and induction condition have been optimized for pinocembrin production. The results and engineering strategies demonstrated here would hold promise for the ATP level improvement of other flavonoids by CRISPRi system, thereby facilitating other flavonoids production.


Assuntos
Trifosfato de Adenosina/metabolismo , Flavanonas/biossíntese , Engenharia Metabólica/métodos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Escherichia coli , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Engenharia Genética , Metionina Adenosiltransferase/química , Metionina Adenosiltransferase/genética , Fosfotransferases (Aceptor do Grupo Carboxila)/química , Fosfotransferases (Aceptor do Grupo Carboxila)/genética
15.
Appl Microbiol Biotechnol ; 102(18): 7837-7847, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29998412

RESUMO

A whole-cell (cadaverine-producing strain, Escherichia coli AST3) immobilization method was developed for improving catalytic activity and cadaverine tolerance during cadaverine production. Cell-immobilized beads were prepared by polyvinyl alcohol (PVA) and sodium alginate (SA) based on their advantages in biocatalyst activity recovery and mechanical strength. The following optimal immobilization conditions were established using response surface methodology: 3.62% SA, 4.71% PVA, 4.21% CaCl2, calcification, 12 h, and freezing for 16 h at - 80 °C, with a cell concentration of 0.3% (g dry cell weight (DCW) per 100 mL) of immobilized beads. After a 2-h bioconversion, the immobilized beads maintained 85% of their original biocatalyst activity, which was 1.8-fold higher than that of free cells. Furthermore, the effects of cell protectants on immobilized biocatalyst activity were examined by fed-batch bioconversion experiments. The results showed that the addition of polyvinylpyrrolidone (PVP) into the immobilized matrix effectively protected biocatalyst activity, with 95% of the relative activity remaining after the 2-h bioconversion. The performance of PVA-SA-PVP-immobilized E. coli AST3 showed continuous production of cadaverine, with an average cadaverine yield of 29 ± 1 g gDCW-1 h-1 after 12 h, suggesting that this method is capable of industrial scale cadaverine production.


Assuntos
Cadaverina/metabolismo , Cadaverina/farmacologia , Citoproteção/efeitos dos fármacos , Alginatos/metabolismo , Cadaverina/biossíntese , Catálise , Álcool de Polivinil/metabolismo
16.
Microb Cell Fact ; 16(1): 52, 2017 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-28347340

RESUMO

BACKGROUND: The six-carbon circular non-proteinogenic compound L-pipecolic acid is an important chiral drug intermediate with many applications in the pharmaceutical industry. In the present study, we developed a metabolically engineered strain of Escherichia coli for the overproduction of L-pipecolic acid from glucose. RESULTS: The metabolic pathway from L-lysine to L-pipecolic acid was constructed initially by introducing lysine cyclodeaminase (LCD). Next, L-lysine metabolic flux from glucose was amplified by the plasmid-based overexpression of dapA, lysC, and lysA under the control of the strong trc promoter to increase the biosynthetic pool of the precursor L-lysine. Additionally, since the catalytic efficiency of the key enzyme LCD is limited by the cofactor NAD+, the intracellular pyridine nucleotide concentration was rebalanced by expressing the pntAB gene encoding the transhydrogenase, which elevated the proportion of LCD with bound NAD+ and enhanced L-pipecolic acid production significantly. Further, optimization of Fe2+ and surfactant in the fermentation process resulted in 5.33 g/L L-pipecolic acid, with a yield of 0.13 g/g of glucose via fed-batch cultivation. CONCLUSIONS: We expanded the metabolic pathway for the synthesis of the chiral pharmaceutical intermediate L-pipecolic acid in E. coli. Using the engineered E. coli, a fast and efficient fermentative production of L-pipecolic acid was achieved. This strategy could be applied to the biosynthesis of other commercially and industrially important chiral compounds containing piperidine rings.


Assuntos
Escherichia coli/genética , Escherichia coli/metabolismo , Engenharia Metabólica/métodos , Redes e Vias Metabólicas/genética , Ácidos Pipecólicos/metabolismo , Amônia-Liases/genética , Técnicas de Cultura Celular por Lotes , Proteínas de Escherichia coli/genética , Fermentação , Expressão Gênica , Glucose/metabolismo , NAD/metabolismo , NADP Trans-Hidrogenases/genética , Ácidos Pipecólicos/química , Plasmídeos , Regiões Promotoras Genéticas
17.
J Ind Microbiol Biotechnol ; 43(4): 557-66, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26733394

RESUMO

The development of efficient microbial processes for pinocembrin production has attracted considerable attention. However, pinocembrin biosynthetic efficiency is greatly limited by the low availability of the malonyl-CoA cofactor in Escherichia coli. Fatty acid biosynthesis is the only metabolic process in E. coli that consumes malonyl-CoA; therefore, we overexpressed the fatty acid biosynthetic pathway enzymes ß-ketoacyl-ACP synthase III (FabH) and ß-ketoacyl-ACP synthase II (FabF) alone and in combination, and investigated the effect on malonyl-CoA. Interestingly, overexpressing FabH, FabF or both enzymes in E. coli BL21 (DE3) decreased fatty acid synthesis and increased cellular malonyl-CoA levels 1.4-, 1.6-, and 1.2-fold, respectively. Furthermore, pinocembrin production was increased 10.6-, 31.8-, and 5.87-fold in recombinant strains overexpressing FabH, FabF and both enzymes, respectively. Overexpression of FabF, therefore, triggered the highest pinocembrin production and malonyl-CoA levels. The addition of cerulenin further increased pinocembrin production in the FabF-overexpressing strain, from 25.8 to 29.9 mg/L. These results demonstrated that overexpressing fatty acid synthases can increase malonyl-CoA availability and improve pinocembrin production in a recombinant E. coli host. This strategy may hold promise for the production of other important natural products in which cellular malonyl-CoA is rate limiting.


Assuntos
Reatores Biológicos , Escherichia coli/genética , Escherichia coli/metabolismo , Ácidos Graxos/biossíntese , Flavanonas/biossíntese , Engenharia Metabólica , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/genética , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/metabolismo , Vias Biossintéticas/genética , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Malonil Coenzima A/metabolismo
18.
Biotechnol Lett ; 37(4): 799-806, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25515797

RESUMO

The effect of fusing the PelB signal sequence to lysine/cadaverine antiporter (CadB) on the bioconversion of L-lysine to cadaverine was investigated. To construct a whole-cell biocatalyst for cadaverine production, four expression plasmids were constructed for the co-expression of lysine decarboxylase (CadA) and lysine/cadaverine antiporter (CadB) in Escherichia coli. Expressing CadB with the PelB signal sequence increased cadaverine production by 12%, and the optimal expression plasmid, pETDuet-pelB-CadB-CadA, contained two T7 promoter-controlled genes, CadA and the PelB-CadB fusion protein. Based on pETDuet-pelB-CadB-CadA, a whole-cell system for the bioconversion of L-lysine to cadaverine was constructed, and three strategies for L-lysine feeding were evaluated to eliminate the substrate inhibition problem. A cadaverine titer of 221 g l(-1) with a molar yield of 92% from lysine was obtained.


Assuntos
Sistemas de Transporte de Aminoácidos/metabolismo , Antiporters/metabolismo , Proteínas de Bactérias/metabolismo , Cadaverina/metabolismo , Carboxiliases/metabolismo , Escherichia coli/metabolismo , Lisina/metabolismo , Engenharia Metabólica , Redes e Vias Metabólicas , Sistemas de Transporte de Aminoácidos/genética , Antiporters/genética , Proteínas de Bactérias/genética , Bacteriófago T7/genética , Carboxiliases/genética , Escherichia coli/genética , Expressão Gênica , Plasmídeos , Regiões Promotoras Genéticas
19.
J Craniomaxillofac Surg ; 52(10): 1095-1108, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39003218

RESUMO

This meta-analysis aimed to elucidate the effects of platelet-rich fibrin (PRF) on the recovery of alveolar bone after surgical removal of the mandibular third molars. PubMed, Cochrane Library, Web of Science, and Embase databases were searched from the inception to February 2023 for relevant studies on the application of PRF after the extraction of impacted mandibular third molars, with the language limited to English. Literature screening was conducted by two independent researchers. The Cochrane risk-of-bias tool was adopted for quality evaluation, and Stata 15.0 was used for statistical analysis. A total of 33 randomized controlled trials were included in the present study. Following surgical removal of the mandibular third molars, 1139 tooth sockets were filled with PRF, while 1138 sockets were sutured after conventional saline irrigation. The meta-analyses showed that PRF can relieve pain [(RR 0.454; 95% CI 0.23, 0.891); (SMD -0.74; 95% CI -0.97, 0.52)], improve swelling (SMD -1.48; 95% CI -1.90, -1.06), alleviate trismus (SMD -0.35; 95% CI -0.51, -0.19), reduce dry socket (SMD -0.18; 95% CI -030, -0.05), and promote bone tissue healing (SMD 2.34; 95% CI 0.18, 4.51). The current study confirms that PRF can reduce some postoperative complications. Local application of PRF after lower third molar extraction is a viable method for relieving pain and swelling, reducing the incidence of dry socket and trismus, and increasing bone density. However, whether it can promote soft tissue healing remains unclear. For patients undergoing complicated surgical extraction, local application of PRF into the sockets might be a good option.


Assuntos
Dente Serotino , Fibrina Rica em Plaquetas , Extração Dentária , Humanos , Dente Serotino/cirurgia , Dente Impactado/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Mandíbula/cirurgia , Alvéolo Dental/cirurgia
20.
J Agric Food Chem ; 72(33): 18353-18364, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39165161

RESUMO

Hyphantria cunea (Lepidoptera: Erebidae) is difficult and costly to control as a quarantine pest found globally. Sex pheromone trapping is an effective measure for its population monitoring and control; however, the peripheral neural mechanism of sex pheromone recognition in H. cunea remains unclear. An electrophysiological analysis showed that both male and female moths of H. cunea responded to four components of sex pheromones and the responses of male moths were stronger than those of the female moths. We identified three types of trichoid sensilla (ST) responsive to sex pheromones using the single sensillum recording technique. Each type was involved in recognizing 9R, 10S-epoxy-1, Z3, Z6-heneicosatriene (1, Z3, Z6-9S, 10R-epoxy-21Hy). Four peripheral neurons involved in the olfactory encoding of sex pheromones were identified. Four candidate pheromone receptor (PR) genes, HcunPR1a, HcunPR1b, HcunPR3, and HcunPR4, were screened by transcriptome sequencing. All of them were highly expressed in the antennae of males, except for HcunPR4, which was highly expressed in the antennae of females. Functional identification showed that HcunPR1a responded to sex pheromone. Other HcunPRs were not functionally identified. In summary, neurons involved in sex pheromone recognition of H. cunea were located in the ST, and HcunPR1a recognized secondary pheromone components 1, Z3, Z6-9S, 10R-epoxy-21Hy. Interestingly, PRs that recognize the main components of the sex pheromone may be located in an unknown branch of the olfactory receptor and merit further study. Our findings provide a better understanding of the peripheral neural coding mechanism of type II sex pheromones, and HcunPR1a may provide a target for the subsequent development of highly effective and specific biopesticides for H. cunea.


Assuntos
Proteínas de Insetos , Mariposas , Receptores de Feromônios , Atrativos Sexuais , Animais , Atrativos Sexuais/metabolismo , Mariposas/fisiologia , Mariposas/genética , Mariposas/metabolismo , Masculino , Feminino , Receptores de Feromônios/genética , Receptores de Feromônios/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Neurônios/metabolismo
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